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Author name code: lamy
ADS astronomy entries on 2022-09-14
author:Lamy, P.L.

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Title: Linking Small-scale Solar Wind Properties with Large-scale
    Coronal Source Regions through Joint Parker Solar Probe-Metis/Solar
    Orbiter Observations
Authors: Telloni, Daniele; Zank, Gary P.; Sorriso-Valvo, Luca;
   D'Amicis, Raffaella; Panasenco, Olga; Susino, Roberto; Bruno, Roberto;
   Perrone, Denise; Adhikari, Laxman; Liang, Haoming; Nakanotani, Masaru;
   Zhao, Lingling; Hadid, Lina Z.; Sánchez-Cano, Beatriz; Verscharen,
   Daniel; Velli, Marco; Grimani, Catia; Marino, Raffaele; Carbone,
   Francesco; Mancuso, Salvatore; Biondo, Ruggero; Pagano, Paolo; Reale,
   Fabio; Bale, Stuart D.; Kasper, Justin C.; Case, Anthony W.; de Wit,
   Thierry Dudok; Goetz, Keith; Harvey, Peter R.; Korreck, Kelly E.;
   Larson, Davin; Livi, Roberto; MacDowall, Robert J.; Malaspina, David
   M.; Pulupa, Marc; Stevens, Michael L.; Whittlesey, Phyllis; Romoli,
   Marco; Andretta, Vincenzo; Deppo, Vania Da; Fineschi, Silvano; Heinzel,
   Petr; Moses, John D.; Naletto, Giampiero; Nicolini, Gianalfredo;
   Spadaro, Daniele; Stangalini, Marco; Teriaca, Luca; Capobianco,
   Gerardo; Capuano, Giuseppe E.; Casini, Chiara; Casti, Marta; Chioetto,
   Paolo; Corso, Alain J.; Leo, Yara De; Fabi, Michele; Frassati,
   Federica; Frassetto, Fabio; Giordano, Silvio; Guglielmino, Salvo L.;
   Jerse, Giovanna; Landini, Federico; Liberatore, Alessandro; Magli,
   Enrico; Massone, Giuseppe; Messerotti, Mauro; Pancrazzi, Maurizio;
   Pelizzo, Maria G.; Romano, Paolo; Sasso, Clementina; Schühle, Udo;
   Slemer, Alessandra; Straus, Thomas; Uslenghi, Michela; Volpicelli,
   Cosimo A.; Zangrilli, Luca; Zuppella, Paola; Abbo, Lucia; Auchère,
   Frédéric; Cuadrado, Regina Aznar; Berlicki, Arkadiusz; Ciaravella,
   Angela; Lamy, Philippe; Lanzafame, Alessandro; Malvezzi, Marco;
   Nicolosi, Piergiorgio; Nisticò, Giuseppe; Peter, Hardi; Solanki,
   Sami K.; Strachan, Leonard; Tsinganos, Kanaris; Ventura, Rita; Vial,
   Jean-Claude; Woch, Joachim; Zimbardo, Gaetano
2022ApJ...935..112T    Altcode:
  The solar wind measured in situ by Parker Solar Probe in the very
  inner heliosphere is studied in combination with the remote-sensing
  observation of the coronal source region provided by the METIS
  coronagraph aboard Solar Orbiter. The coronal outflows observed near
  the ecliptic by Metis on 2021 January 17 at 16:30 UT, between 3.5 and
  6.3 R <SUB>⊙</SUB> above the eastern solar limb, can be associated
  with the streams sampled by PSP at 0.11 and 0.26 au from the Sun,
  in two time intervals almost 5 days apart. The two plasma flows
  come from two distinct source regions, characterized by different
  magnetic field polarity and intensity at the coronal base. It follows
  that both the global and local properties of the two streams are
  different. Specifically, the solar wind emanating from the stronger
  magnetic field region has a lower bulk flux density, as expected,
  and is in a state of well-developed Alfvénic turbulence, with low
  intermittency. This is interpreted in terms of slab turbulence in the
  context of nearly incompressible magnetohydrodynamics. Conversely,
  the highly intermittent and poorly developed turbulent behavior of the
  solar wind from the weaker magnetic field region is presumably due to
  large magnetic deflections most likely attributed to the presence of
  switchbacks of interchange reconnection origin.

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Title: Science with the ASPIICS coronagraph onboard PROBA-3
Authors: Gunár, Stanislav; Fineschi, Silvano; Inhester, Bernd;
   Zhukov, Andrei; Mierla, Marilena; Tsinganos, Kanaris; Lamy, Philippe;
   Rudawy, Pawel
2022cosp...44.1326G    Altcode:
  The giant distributed coronagraph ASPIICS onboard the formation-flying
  mission PROBA-3 of ESA will investigate hitherto practically
  unexplored inner depths of the solar corona. This region lies above
  the reach of disk imagers such as SDO and below the inner limit of
  other coronagraphs. Although difficult to observe, the inner corona
  is a place of great interest. This is where the fast solar wind gets
  accelerated to supersonic velocities and where CMEs also reach their
  maximum accelerations. It is also the place where the transition between
  the regions of the closed and open magnetic field often happens and
  the slow solar wind originates. Thanks to its field of view (2048 x
  2048 pixels) reaching from 1.098 to 3 Rsun, good spatial resolution
  (2.8 arcsec per pixel) and minimized straylight, ASPIICS will be able
  to follow the connectivity of magnetic structures in corona down to the
  solar surface. When coupled with regular (every week) long duration
  (up to 6 hours) observations, it will allow us to comprehensively
  compare and validate the MHD models of the large-scale coronal magnetic
  field configuration and its evolution. The inner field-of-view limit
  reaching very close to the solar surface will also enable us to study
  the onset and early evolution of CMEs or to follow erupting prominences
  beyond the reaches of the disk imagers. Thanks to the high cadence
  (up to 2 seconds) we can start to investigate the manifestation of
  small-scale solar dynamic processes within the inner corona. Moreover,
  together with the DARA instrument measuring the total solar irradiance
  onboard the occulting spacecraft of PROBA-3, ASPIICS will help us to
  understand the partition of the magnetic free energy into the radiative
  energy and the kinetic energy during solar eruptions. The pursuit of
  these science goals will happen in coordination with Solar Orbiter,
  Parker Solar Probe, Aditya-L1, and ASO-S. The synergies stemming from
  these collaborations are promising to lead us into a golden age of
  space coronagraphy.

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Title: Polarimetric Studies of a Fast Coronal Mass Ejection
Authors: Mierla, Marilena; Inhester, Bernd; Zhukov, Andrei N.; Shestov,
   Sergei V.; Bemporad, Alessandro; Lamy, Philippe; Koutchmy, Serge
2022SoPh..297...78M    Altcode: 2022arXiv220604411M
  In this work we performed a polarimetric study of a fast and wide
  coronal mass ejection (CME) observed on 12 July 2012 by the COR1 and
  COR2 instruments onboard the Solar TErrestrial RElations Observatory
  (STEREO) mission. The CME source region was an X1.4 flare located at
  approximately S15W01 on the solar disk, as observed from the Earth's
  perspective. The position of the CME as derived from the 3D Graduated
  Cylindrical Shell (GCS) reconstruction method was at around S18W00
  at 2.5 solar radii and S07W00 at 5.7 solar radii, meaning that the
  CME was deflected towards the Equator while propagating outward in
  the corona. The projected speed of the leading edge of the CME also
  evolved from around 200 km s<SUP>−1</SUP> in the lower corona to
  around 1000 km s<SUP>−1</SUP> in the COR2 field of view. The degree
  of polarisation of the CME is around 65% but it can go as high as 80%
  in some CME regions. The CME showed deviation of the polarisation
  angle from the tangential in the range of 10 - 15<SUP>∘</SUP> (or
  more). Our analysis showed that this is mostly due to the fact that the
  sequence of three polarised images from where the polarised parameters
  are derived is not taken simultaneously, but at a difference of a few
  seconds in time. In this interval of time, the CME moves by at least
  two pixels in the FOV of the instruments and this displacement results
  in uncertainties in the polarisation parameters (degree of polarisation,
  polarisation angle, etc.). We propose some steps forward to improve the
  derivation of the polarisation. This study is important for analysing
  the future data from instruments with polarisation capabilities.

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Title: Three-Dimensional Structure of the Corona During WHPI Campaign
    Rotations CR-2219 and CR-2223
Authors: Lloveras, D. G.; Vásquez, A. M.; Nuevo, F. A.; Frazin, R. A.;
   Manchester, W.; Sachdeva, N.; Van der Holst, B.; Lamy, P.; Gilardy, H.
2022JGRA..12730406L    Altcode:
  Differential emission measure tomography (DEMT) and white light
  (WL) tomography were applied to study the three-dimensional (3D)
  structure of the global solar corona for two Whole Heliosphere
  and Planetary Interactions campaign periods, Carrington rotations
  2219 and 2223. With DEMT, Solar Dynamics Observatory/Atmospheric
  Imaging Assembly images were used to reconstruct the 3D coronal
  electron density and temperature in the range of heliocentric
  distance 1.02-1.25 R<SUB>⊙</SUB>. With WL tomography, Solar and
  Heliospheric Observatory/Large Angle and Spectrometric COronagraph-C2
  images were used to reconstruct the 3D electron density in the range
  of heliocentric distance 2.5-6.0 R<SUB>⊙</SUB>. The two periods
  were also simulated with the 3D-magneto-hydrodynamic Alfvén Wave
  Solar Model (AWSoM), and its results compared in detail with the
  reconstructions. The DEMT analysis reveals a 20% less dense and 20%
  hotter corona than for rotations corresponding to the solar cycle
  23/24 deep minimum. The electron density and temperature of the AWSoM
  model agree with DEMT results within 10% and 20%, respectively, while
  its electron density overestimates results of WL tomography up to
  75%. The slow (fast) component of the terminal wind speed of the model
  is found to be associated with field lines characterized by larger
  (smaller) values of the tomographic density and temperature at the
  coronal base. DEMT reconstructions reveal the coronal plasma to be
  ubiquitously characterized by temperature variability of up to ≈45%
  over spatial scales of order ∼10<SUP>4</SUP> km. Taking into account
  this level of fine-structure by global models may be consequential
  for their predictions on wave propagation in the corona.

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Title: M-type (22) Kalliope: A tiny Mercury
Authors: Ferrais, M.; Jorda, L.; Vernazza, P.; Carry, B.; Brož, M.;
   Rambaux, N.; Hanuš, J.; Dudziński, G.; Bartczak, P.; Vachier, F.;
   Aristidi, E.; Beck, P.; Marchis, F.; Marsset, M.; Viikinkoski, M.;
   Fetick, R.; Drouard, A.; Fusco, T.; Birlan, M.; Podlewska-Gaca, E.;
   Burbine, T. H.; Dyar, M. D.; Bendjoya, P.; Benkhaldoun, Z.; Berthier,
   J.; Castillo-Rogez, J.; Cipriani, F.; Colas, F.; Dumas, C.; Ďurech,
   J.; Fauvaud, S.; Grice, J.; Jehin, E.; Kaasalainen, M.; Kryszczynska,
   A.; Lamy, P.; Le Coroller, H.; Marciniak, A.; Michalowski, T.; Michel,
   P.; Prieur, J. -L.; Reddy, V.; Rivet, J. -P.; Santana-Ros, T.; Scardia,
   M.; Tanga, P.; Vigan, A.; Witasse, O.; Yang, B.
2022A&A...662A..71F    Altcode:
  Context. Asteroid (22) Kalliope is the second largest M-type asteroid
  in the main belt and is orbited by a satellite, Linus. Whereas the
  mass of Kalliope is already well constrained thanks to the presence of
  a moon, its volume is still poorly known, leading to uncertainties on
  its bulk density and internal structure. <BR /> Aims: We aim to refine
  the shape of (22) Kalliope and thus its diameter and bulk density,
  as well as the orbit of its moon to better constrain its mass,
  hence density and internal structure. <BR /> Methods: We acquired
  disk-resolved observations of (22) Kalliope using the VLT/SPHERE/ZIMPOL
  instrument to reconstruct its three-dimensional (3D) shape using three
  different modeling techniques. These images were also used together
  with new speckle observations at the C2PU/PISCO instrument as well
  as archival images from other large ground-based telescopes to refine
  the orbit of Linus. <BR /> Results: The volume of (22) Kalliope given
  by the shape models, corresponding to D = 150 ± 5 km, and the mass
  constrained by its satellite's orbit yield a density of ρ = 4.40
  ± 0.46 g cm<SUP>−3</SUP>. This high density potentially makes
  (22) Kalliope the densest known small body in the Solar System. A
  macroporosity in the 10-25% range (as expected for this mass and
  size), implies a grain density in the 4.8-5.9 g cm<SUP>−3</SUP>
  range. Kalliope's high bulk density, along with its silicate-rich
  surface implied by its low radar albedo, implies a differentiated
  interior with metal contributing to most of the mass of the body. <BR
  /> Conclusions: Kalliope's high metal content (40-60%) along with its
  metal-poor mantle makes it the smallest known Mercury-like body. A
  large impact at the origin of the formation of the moon Linus is
  likely the cause of its high metal content and density. <P />Reduced
  images are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/662/A71">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/662/A71</A>
  <P />Based on observations made with ESO Telescopes at the Paranal
  Observatory under program ID 199.C-0074 (PI: P. Vernazza).

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Title: The State of the White-Light Corona over the Minimum and
    Ascending Phases of Solar Cycle 25 -- Comparison with Past Cycles
Authors: Lamy, Philippe; Gilardy, Hugo
2022arXiv220506462L    Altcode:
  We report on the state of the corona over the minimum and ascending
  phases of Solar Cycle (SC) 25 on the basis of the temporal evolutions of
  its radiance and of the properties of coronal mass ejections (CMEs) as
  determined from white-light observations performed by the SOHO/LASCO-C2
  coronagraph. These evolutions are further compared with those determined
  during the past two SC. The integrated radiance of the K-corona and
  the occurrence rate of CMEs closely track the indices/proxies of solar
  activity, prominently the total magnetic field for the radiance and
  the radio flux for the CMEs, all undergoing a steep increase during the
  ascending phase of SC 25. This increase is much steeper than anticipated
  on the basis of the predicted quasi similarity between SC 25 and 24,
  and is confirmed by the recent evolution of the sunspot number. The
  radiance reached the same base level during the minima of SC 24 and
  25, but the latitudinal extent of the streamer belt differed, being
  flatter during the latter minimum and in fact more similar to that of
  the minimum of SC 23. Phasing the descending branches of SC 23 and 24
  led to a duration of SC 24 of 11.0 years, similar to that given by the
  sunspot number. In contrast, the base level of the occurrence rate of
  CMEs during the minimum of SC 25 was significantly larger than during
  the two previous minima. The southern hemisphere is conspicuously more
  active than the northern one in agreement with several predictions
  and the current evolution of the hemispheric sunspot numbers. The mean
  apparent width of CMEs and the number of halo CMEs remains at relatively
  large, constant levels throughout the early phase of SC 25 implying the
  persistence of weak total pressure in the heliosphere. These results and
  the perspective of a corona more active than anticipated are extremely
  promising for the forthcoming observations by Solar Orbiter and Parker
  Solar Probe.

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Title: VizieR Online Data Catalog: (22) Kalliope SPHERE images and
    shape models (Ferrais+, 2022)
Authors: Ferrais, M.; Jorda, L.; Vernazza, P.; Carry, B.; Broz, M.;
   Rambaux, N.; Hanus, J.; Dudzinski, G.; Bartczak, P.; Vachier, F.;
   Aristidi, E.; Beck, P.; Marchis, F.; Marsset, M.; Viikinkoski, M.;
   Fetick, R.; Drouard, A.; Fusco, T.; Birlan, M.; Podlewska-Gaca, E.;
   Burbine, T. H.; Dyar, M. D.; Bendjoya, P.; Benkhaldoun, Z.; Berthier,
   J.; Castillo-Rogez, J.; Cipriani, F.; Colas, F.; Dumas, C.; Durech,
   J.; Fauvaud, S.; Grice, J.; Jehin, E.; Kaasalainen, M.; Kryszczynska,
   A.; Lamy, P.; Le Coroller, H.; Marciniak, A.; Michalowski, T.; Michel,
   P.; Prieur, J. -L.; Reddy, V.; Rivet, J. -P.; Santana-Ros, T.; Scardia,
   M.; Tanga, P.; Vigan, A.; Witasse, O.; Yang, B.
2022yCat..36620071F    Altcode:
  We obtained 35 images of Kalliope at 7 epochs in 2018 and 2019 using
  VLT/SPHERE/ZIMPOL. All images were reduced following the procedure
  described in Vernazza et al. (2018A&amp;A...618A.154V). <P />objects:
  -------------------------------------------------------------------
  Planet Name H Diam i e a mag km deg AU
  -------------------------------------------------------------------
  22 Kalliope 6.53 150 13.700494 0.09838130 2.91020240
  -------------------------------------------------------------------
  <P />(10 data files).

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Title: Observation of the Solar F-corona from Space
Authors: Lamy, Philippe; Gilardy, Hugo; Llebaria, Antoine
2022arXiv220211533L    Altcode:
  We present a review of the observations of the solar F-corona from
  space with a special emphasis of the 25 years of continuous monitoring
  achieved by the LASCO-C2 and C3 coronagraphs. Our work includes images
  obtained by the navigation cameras of the Clementine spacecraft, the
  SECCHI/HI-1A heliospheric imager onboard STEREO-A, and the Wide Field
  Imager for Solar Probe onboard the Parker Solar Probe. The connection
  to the zodiacal light is considered based on ground- and space-based
  observations, prominently from the past Helios, IRAS, COBE, and IRAKI
  missions. The characteristic radiance profiles along the equatorial and
  polar directions follow power laws in the 5°-50° range of elongation,
  with constant power exponents of -2.33 and -2.55. Both profiles connect
  extremely well to the corresponding standard profiles of the zodiacal
  light. The LASCO equatorial profile exhibits a shoulder implying a 17%
  decrease of the radiance within 10Rsun that may be explained by the
  disappearance of organic materials within 0.3 AU. LASCO detected for
  the first time a secular variation of the F-corona, an increase at
  a rate of 0.46% per year of the integrated radiance in the LASCO-C3
  FoV. This is likely the first observational evidence of the role
  of collisions in the inner zodiacal cloud. A composite of C2 and C3
  images produced the LASCO reference map of the radiance of the F-corona
  from 2 to 30Rsun and, by combining with ground-based measurements, the
  LASCO extended map from 1 to 6 Rsun. The plane of symmetry of the inner
  zodiacal cloud is strongly warped, its inclination increasing towards
  the planes of the inner planets and ultimately the solar equator. In
  contrast, its longitude of ascending node is found to be constant and
  equal to 87.6°. LASCO did not detect any small scale structures such
  as putative rings occasionally reported during solar eclipses.

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Title: The first coronal mass ejection observed in both visible-light
    and UV H I Ly-α channels of the Metis coronagraph on board Solar
    Orbiter
Authors: Andretta, V.; Bemporad, A.; De Leo, Y.; Jerse, G.; Landini,
   F.; Mierla, M.; Naletto, G.; Romoli, M.; Sasso, C.; Slemer, A.;
   Spadaro, D.; Susino, R.; Talpeanu, D. -C.; Telloni, D.; Teriaca, L.;
   Uslenghi, M.; Antonucci, E.; Auchère, F.; Berghmans, D.; Berlicki,
   A.; Capobianco, G.; Capuano, G. E.; Casini, C.; Casti, M.; Chioetto,
   P.; Da Deppo, V.; Fabi, M.; Fineschi, S.; Frassati, F.; Frassetto,
   F.; Giordano, S.; Grimani, C.; Heinzel, P.; Liberatore, A.; Magli, E.;
   Massone, G.; Messerotti, M.; Moses, D.; Nicolini, G.; Pancrazzi, M.;
   Pelizzo, M. -G.; Romano, P.; Schühle, U.; Stangalini, M.; Straus,
   Th.; Volpicelli, C. A.; Zangrilli, L.; Zuppella, P.; Abbo, L.; Aznar
   Cuadrado, R.; Bruno, R.; Ciaravella, A.; D'Amicis, R.; Lamy, P.;
   Lanzafame, A.; Malvezzi, A. M.; Nicolosi, P.; Nisticò, G.; Peter,
   H.; Plainaki, C.; Poletto, L.; Reale, F.; Solanki, S. K.; Strachan,
   L.; Tondello, G.; Tsinganos, K.; Velli, M.; Ventura, R.; Vial, J. -C.;
   Woch, J.; Zimbardo, G.
2021A&A...656L..14A    Altcode:
  Context. The Metis coronagraph on board Solar Orbiter offers a new
  view of coronal mass ejections (CMEs), observing them for the first
  time with simultaneous images acquired with a broad-band filter in
  the visible-light interval and with a narrow-band filter around the
  H I Ly-α line at 121.567 nm, the so-called Metis UV channel. <BR />
  Aims: We show the first Metis observations of a CME, obtained on 16
  and 17 January 2021. The event was also observed by the EUI/FSI imager
  on board Solar Orbiter, as well as by other space-based coronagraphs,
  such as STEREO-A/COR2 and SOHO/LASCO/C2, whose images are combined here
  with Metis data. <BR /> Methods: Different images are analysed here
  to reconstruct the 3D orientation of the expanding CME flux rope using
  the graduated cylindrical shell model. This also allows us to identify
  the possible location of the source region. Measurements of the CME
  kinematics allow us to quantify the expected Doppler dimming in the
  Ly-α channel. <BR /> Results: Observations show that most CME features
  seen in the visible-light images are also seen in the Ly-α images,
  although some features in the latter channel appear more structured
  than their visible-light counterparts. We estimated the expansion
  velocity of this event to be below 140 km s<SUP>−1</SUP>. Hence,
  these observations can be understood by assuming that Doppler dimming
  effects do not strongly reduce the Ly-α emission from the CME. These
  velocities are comparable with or smaller than the radial velocities
  inferred from the same data in a similar coronal structure on the
  east side of the Sun. <BR /> Conclusions: The first observations by
  Metis of a CME demonstrate the capability of the instrument to provide
  valuable and novel information on the structure and dynamics of these
  coronal events. Considering also its diagnostics capabilities regarding
  the conditions of the ambient corona, Metis promises to significantly
  advance our knowledge of such phenomena. <P />Movies are available at <A
  href="https://www.aanda.org/10.1051/0004-6361/202142407/olm">https://www.aanda.org</A>

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Title: First light observations of the solar wind in the outer corona
    with the Metis coronagraph
Authors: Romoli, M.; Antonucci, E.; Andretta, V.; Capuano, G. E.; Da
   Deppo, V.; De Leo, Y.; Downs, C.; Fineschi, S.; Heinzel, P.; Landini,
   F.; Liberatore, A.; Naletto, G.; Nicolini, G.; Pancrazzi, M.; Sasso,
   C.; Spadaro, D.; Susino, R.; Telloni, D.; Teriaca, L.; Uslenghi,
   M.; Wang, Y. -M.; Bemporad, A.; Capobianco, G.; Casti, M.; Fabi, M.;
   Frassati, F.; Frassetto, F.; Giordano, S.; Grimani, C.; Jerse, G.;
   Magli, E.; Massone, G.; Messerotti, M.; Moses, D.; Pelizzo, M. -G.;
   Romano, P.; Schühle, U.; Slemer, A.; Stangalini, M.; Straus, T.;
   Volpicelli, C. A.; Zangrilli, L.; Zuppella, P.; Abbo, L.; Auchère,
   F.; Aznar Cuadrado, R.; Berlicki, A.; Bruno, R.; Ciaravella, A.;
   D'Amicis, R.; Lamy, P.; Lanzafame, A.; Malvezzi, A. M.; Nicolosi,
   P.; Nisticò, G.; Peter, H.; Plainaki, C.; Poletto, L.; Reale, F.;
   Solanki, S. K.; Strachan, L.; Tondello, G.; Tsinganos, K.; Velli,
   M.; Ventura, R.; Vial, J. -C.; Woch, J.; Zimbardo, G.
2021A&A...656A..32R    Altcode: 2021arXiv210613344R
  In this work, we present an investigation of the wind in the solar
  corona that has been initiated by observations of the resonantly
  scattered ultraviolet emission of the coronal plasma obtained with
  UVCS-SOHO, designed to measure the wind outflow speed by applying
  Doppler dimming diagnostics. Metis on Solar Orbiter complements the
  UVCS spectroscopic observations that were performed during solar
  activity cycle 23 by simultaneously imaging the polarized visible
  light and the H I Lyman-α corona in order to obtain high spatial and
  temporal resolution maps of the outward velocity of the continuously
  expanding solar atmosphere. The Metis observations, taken on May 15,
  2020, provide the first H I Lyman-α images of the extended corona
  and the first instantaneous map of the speed of the coronal plasma
  outflows during the minimum of solar activity and allow us to identify
  the layer where the slow wind flow is observed. The polarized visible
  light (580-640 nm) and the ultraviolet H I Lyα (121.6 nm) coronal
  emissions, obtained with the two Metis channels, were combined in
  order to measure the dimming of the UV emission relative to a static
  corona. This effect is caused by the outward motion of the coronal
  plasma along the direction of incidence of the chromospheric photons
  on the coronal neutral hydrogen. The plasma outflow velocity was then
  derived as a function of the measured Doppler dimming. The static
  corona UV emission was simulated on the basis of the plasma electron
  density inferred from the polarized visible light. This study leads
  to the identification, in the velocity maps of the solar corona, of
  the high-density layer about ±10° wide, centered on the extension
  of a quiet equatorial streamer present at the east limb - the coronal
  origin of the heliospheric current sheet - where the slowest wind
  flows at about 160 ± 18 km s<SUP>−1</SUP> from 4 R<SUB>⊙</SUB>
  to 6 R<SUB>⊙</SUB>. Beyond the boundaries of the high-density layer,
  the wind velocity rapidly increases, marking the transition between
  slow and fast wind in the corona.

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Title: Sample return of primitive matter from the outer Solar System
Authors: Vernazza, P.; Beck, P.; Ruesch, O.; Bischoff, A.; Bonal,
   L.; Brennecka, G.; Brunetto, R.; Busemann, H.; Carter, J.; Carli, C.;
   Cartier, C.; Ciarniello, M.; Debaille, V.; Delsanti, A.; D'Hendecourt,
   L.; Füri, E.; Groussin, O.; Guilbert-Lepoutre, A.; Helbert, J.; Hoppe,
   P.; Jehin, E.; Jorda, L.; King, A.; Kleine, T.; Lamy, P.; Lasue,
   J.; Le Guillou, C.; Leroux, H.; Leya, I.; Magna, T.; Marrocchi, Y.;
   Morlok, A.; Mousis, O.; Palomba, E.; Piani, L.; Quirico, E.; Remusat,
   L.; Roskosz, M.; Rubin, M.; Russell, S.; Schönbächler, M.; Thomas,
   N.; Villeneuve, J.; Vinogradoff, V.; Wurz, P.; Zanda, B.
2021ExA...tmp..128V    Altcode:
  The last thirty years of cosmochemistry and planetary science have shown
  that one major Solar System reservoir is vastly undersampled in the
  available suite of extra-terrestrial materials, namely small bodies that
  formed in the outer Solar System (&gt;10 AU). Because various dynamical
  evolutionary processes have modified their initial orbits (e.g., giant
  planet migration, resonances), these objects can be found today across
  the entire Solar System as P/D near-Earth and main-belt asteroids,
  Jupiter and Neptune Trojans, comets, Centaurs, and small (diameter
  &lt; 200 km) trans-Neptunian objects. This reservoir is of tremendous
  interest, as it is recognized as the least processed since the dawn of
  the Solar System and thus the closest to the starting materials from
  which the Solar System formed. Some of the next major breakthroughs in
  planetary science will come from studying outer Solar System samples
  (volatiles and refractory constituents) in the laboratory. Yet, this
  can only be achieved by an L-class mission that directly collects
  and returns to Earth materials from this reservoir. It is thus not
  surprising that two White Papers advocating a sample return mission of
  a primitive Solar System small body (ideally a comet) were submitted to
  ESA in response to its Voyage 2050 call for ideas for future L-class
  missions in the 2035-2050 time frame. One of these two White Papers
  is presented in this article.

---------------------------------------------------------
Title: VLT/SPHERE imaging survey of the largest main-belt asteroids:
    Final results and synthesis
Authors: Vernazza, P.; Ferrais, M.; Jorda, L.; Hanuš, J.; Carry,
   B.; Marsset, M.; Brož, M.; Fetick, R.; Viikinkoski, M.; Marchis,
   F.; Vachier, F.; Drouard, A.; Fusco, T.; Birlan, M.; Podlewska-Gaca,
   E.; Rambaux, N.; Neveu, M.; Bartczak, P.; Dudziński, G.; Jehin, E.;
   Beck, P.; Berthier, J.; Castillo-Rogez, J.; Cipriani, F.; Colas, F.;
   Dumas, C.; Ďurech, J.; Grice, J.; Kaasalainen, M.; Kryszczynska, A.;
   Lamy, P.; Le Coroller, H.; Marciniak, A.; Michalowski, T.; Michel,
   P.; Santana-Ros, T.; Tanga, P.; Vigan, A.; Witasse, O.; Yang, B.;
   Antonini, P.; Audejean, M.; Aurard, P.; Behrend, R.; Benkhaldoun,
   Z.; Bosch, J. M.; Chapman, A.; Dalmon, L.; Fauvaud, S.; Hamanowa,
   Hiroko; Hamanowa, Hiromi; His, J.; Jones, A.; Kim, D. -H.; Kim,
   M. -J.; Krajewski, J.; Labrevoir, O.; Leroy, A.; Livet, F.; Molina,
   D.; Montaigut, R.; Oey, J.; Payre, N.; Reddy, V.; Sabin, P.; Sanchez,
   A. G.; Socha, L.
2021A&A...654A..56V    Altcode:
  Context. Until recently, the 3D shape, and therefore density (when
  combining the volume estimate with available mass estimates), and
  surface topography of the vast majority of the largest (D ≥ 100 km)
  main-belt asteroids have remained poorly constrained. The improved
  capabilities of the SPHERE/ZIMPOL instrument have opened new doors
  into ground-based asteroid exploration. <BR /> Aims: To constrain the
  formation and evolution of a representative sample of large asteroids,
  we conducted a high-angular-resolution imaging survey of 42 large
  main-belt asteroids with VLT/SPHERE/ZIMPOL. Our asteroid sample
  comprises 39 bodies with D ≥ 100 km and in particular most D ≥
  200 km main-belt asteroids (20/23). Furthermore, it nicely reflects
  the compositional diversity present in the main belt as the sampled
  bodies belong to the following taxonomic classes: A, B, C, Ch/Cgh,
  E/M/X, K, P/T, S, and V. <BR /> Methods: The SPHERE/ZIMPOL images
  were first used to reconstruct the 3D shape of all targets with both
  the ADAM and MPCD reconstruction methods. We subsequently performed
  a detailed shape analysis and constrained the density of each target
  using available mass estimates including our own mass estimates in
  the case of multiple systems. <BR /> Results: The analysis of the
  reconstructed shapes allowed us to identify two families of objects
  as a function of their diameters, namely "spherical" and "elongated"
  bodies. A difference in rotation period appears to be the main origin
  of this bimodality. In addition, all but one object (216 Kleopatra)
  are located along the Maclaurin sequence with large volatile-rich
  bodies being the closest to the latter. Our results further reveal
  that the primaries of most multiple systems possess a rotation period
  of shorter than 6 h and an elongated shape (c∕a ≤ 0.65). Densities
  in our sample range from ~1.3 g cm<SUP>−3</SUP> (87 Sylvia) to ~4.3 g
  cm<SUP>−3</SUP> (22 Kalliope). Furthermore, the density distribution
  appears to be strongly bimodal with volatile-poor (ρ ≥ 2.7 g
  cm<SUP>−3</SUP>) and volatile-rich (ρ ≤ 2.2 g cm<SUP>−3</SUP>)
  bodies. Finally, our survey along with previous observations provides
  evidence in support of the possibility that some C-complex bodies
  could be intrinsically related to IDP-like P- and D-type asteroids,
  representing different layers of a same body (C: core; P/D: outer
  shell). We therefore propose that P/ D-types and some C-types may have
  the same origin in the primordial trans-Neptunian disk. <P />Tables
  A.2 and A.3 are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/654/A56">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/654/A56</A>
  <P />Based on observations made with ESO Telescopes at
  the Paranal Observatory under programme ID 199.C-0074
  (PI: P. Vernazza). <P />The reduced and deconvolved
  images as well as the 3D shape models are available at <A
  href="https://observations.lam.fr/astero/">https://observations.lam.fr/astero/</A>

---------------------------------------------------------
Title: (216) Kleopatra, a low density critically rotating M-type
    asteroid
Authors: Marchis, F.; Jorda, L.; Vernazza, P.; Brož, M.; Hanuš, J.;
   Ferrais, M.; Vachier, F.; Rambaux, N.; Marsset, M.; Viikinkoski, M.;
   Jehin, E.; Benseguane, S.; Podlewska-Gaca, E.; Carry, B.; Drouard,
   A.; Fauvaud, S.; Birlan, M.; Berthier, J.; Bartczak, P.; Dumas, C.;
   Dudziński, G.; Ďurech, J.; Castillo-Rogez, J.; Cipriani, F.; Colas,
   F.; Fetick, R.; Fusco, T.; Grice, J.; Kryszczynska, A.; Lamy, P.;
   Marciniak, A.; Michalowski, T.; Michel, P.; Pajuelo, M.; Santana-Ros,
   T.; Tanga, P.; Vigan, A.; Witasse, O.; Yang, B.
2021A&A...653A..57M    Altcode: 2021arXiv210807207M
  Context. The recent estimates of the 3D shape of the M/Xe-type
  triple asteroid system (216) Kleopatra indicated a density of ~5 g
  cm<SUP>−3</SUP>, which is by far the highest for a small Solar System
  body. Such a high density implies a high metal content as well as a low
  porosity which is not easy to reconcile with its peculiar "dumbbell"
  shape. <BR /> Aims: Given the unprecedented angular resolution of the
  VLT/SPHERE/ZIMPOL camera, here, we aim to constrain the mass (via the
  characterization of the orbits of the moons) and the shape of (216)
  Kleopatra with high accuracy, hence its density. <BR /> Methods:
  We combined our new VLT/SPHERE observations of (216) Kleopatra
  recorded during two apparitions in 2017 and 2018 with archival data
  from the W. M. Keck Observatory, as well as lightcurve, occultation,
  and delay-Doppler images, to derive a model of its 3D shape using two
  different algorithms (ADAM, MPCD). Furthermore, an N-body dynamical
  model allowed us to retrieve the orbital elements of the two moons
  as explained in the accompanying paper. <BR /> Results: The shape
  of (216) Kleopatra is very close to an equilibrium dumbbell figure
  with two lobes and a thick neck. Its volume equivalent diameter
  (118.75 ± 1.40) km and mass (2.97 ± 0.32) × 10<SUP>18</SUP> kg
  (i.e., 56% lower than previously reported) imply a bulk density
  of (3.38 ± 0.50) g cm<SUP>−3</SUP>. Such a low density for a
  supposedly metal-rich body indicates a substantial porosity within
  the primary. This porous structure along with its near equilibrium
  shape is compatible with a formation scenario including a giant impact
  followed by reaccumulation. (216) Kleopatra's current rotation period
  and dumbbell shape imply that it is in a critically rotating state. The
  low effective gravity along the equator of the body, together with
  the equatorial orbits of the moons and possibly rubble-pile structure,
  opens the possibility that the moons formed via mass shedding. <BR />
  Conclusions: (216) Kleopatra is a puzzling multiple system due to the
  unique characteristics of the primary. This system certainly deserves
  particular attention in the future, with the Extremely Large Telescopes
  and possibly a dedicated space mission, to decipher its entire formation
  history. <P />Reduced images are only available at the CDS via anonymous
  ftp to <A href="http://cdsarc.u-strasbg.fr">cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/653/A57">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/653/A57</A>
  <P />Based on observations made with ESO Telescopes at the La Silla
  Paranal Observatory under program 199.C-0074 (PI: Vernazza).

---------------------------------------------------------
Title: VizieR Online Data Catalog: Largest main belt asteroids data
    (Vernazza+, 2021)
Authors: Vernazza, P.; Ferrais, M.; Jorda, L.; Hanua, J.; Carry,
   B.; Marsset, M.; Broz, M.; Fetick, R.; Viikinkoski, M.; Marchis,
   F.; Vachier, F.; Drouard, A.; Fusco, T.; Birlan, M.; Podlewska-Gaca,
   E.; Rambaux, N.; Neveu, M.; Bartczak, P.; Dudzinski, G.; Jehin, E.;
   Beck, P.; Berthier, J.; Castillo-Rogez, J.; Cipriani, F.; Colas, F.;
   Dumas, C.; Durech, J.; Grice, J.; Kaasalainen, M.; Kryszczynska, A.;
   Lamy, P.; Le Coroller, H.; Marciniak, A.; Michalowski, T.; Michel,
   P.; Santana-Ros, T.; Tanga, P.; Vigan, A.; Witasse, O.; Yang, B.;
   Antonini, P.; Audejean, M.; Aurard, P.; Behrend, R.; Benkhaldoun,
   Z.; Bosch, J. M.; Chapman, A.; Dalmon, L.; Fauvaud, S.; Hamanowa,
   Hiroko; Hamanowa, Hiromi; His, J.; Jones, A.; Kim, D. -H.; Kim,
   M. -J.; Krajewski, J.; Labrevoir, O.; Leroy, A.; Livet, F.; Molina,
   D.; Montaigut, R.; Oey, J.; Payre, N.; Reddy, V.; Sabin, P.; Sanchez,
   A. G.; Socha, L.
2021yCat..36540056V    Altcode:
  The baseline observational strategy adopted for our large programme
  has been to image each target with SPHERE/ZIMPOL (i) around opposition
  to ensure an optimal spatial resolution (we restricted the observing
  period so that its angular diameter remained greater than at least 85%
  of that at opposition), (ii) every ~60° in rotation phase in order
  to obtain a satisfactory surface coverage, and (iii) with seeing
  conditions of better than 0.8" and an airmass of below 1.6 in order
  to ensure great observing conditions and thus high-quality data. To
  fulfil these criteria and given that large programmes have the highest
  priority at ESO, we performed our large programme entirely in service
  mode. We would like to stress that this strategy has been key to the
  success of our programme. <P />(3 data files).

---------------------------------------------------------
Title: An advanced multipole model for (216) Kleopatra triple system
Authors: Brož, M.; Marchis, F.; Jorda, L.; Hanuš, J.; Vernazza, P.;
   Ferrais, M.; Vachier, F.; Rambaux, N.; Marsset, M.; Viikinkoski, M.;
   Jehin, E.; Benseguane, S.; Podlewska-Gaca, E.; Carry, B.; Drouard,
   A.; Fauvaud, S.; Birlan, M.; Berthier, J.; Bartczak, P.; Dumas, C.;
   Dudziński, G.; Ďurech, J.; Castillo-Rogez, J.; Cipriani, F.; Colas,
   F.; Fetick, R.; Fusco, T.; Grice, J.; Kryszczynska, A.; Lamy, P.;
   Marciniak, A.; Michalowski, T.; Michel, P.; Pajuelo, M.; Santana-Ros,
   T.; Tanga, P.; Vigan, A.; Vokrouhlický, D.; Witasse, O.; Yang, B.
2021A&A...653A..56B    Altcode: 2021arXiv210509134B
  <BR /> Aims: To interpret adaptive-optics observations of (216)
  Kleopatra, we need to describe an evolution of multiple moons orbiting
  an extremely irregular body and include their mutual interactions. Such
  orbits are generally non-Keplerian and orbital elements are not
  constants. <BR /> Methods: Consequently, we used a modified N-body
  integrator, which was significantly extended to include the multipole
  expansion of the gravitational field up to the order ℓ = 10. Its
  convergence was verified against the `brute-force' algorithm. We
  computed the coefficients C<SUB>ℓm</SUB>, S<SUB>ℓm</SUB> for
  Kleopatra's shape, assuming a constant bulk density. For Solar
  System applications, it was also necessary to implement a variable
  distance and geometry of observations. Our χ<SUP>2</SUP> metric then
  accounts for the absolute astrometry, the relative astrometry (second
  moon with respect to the first), angular velocities, and silhouettes,
  constraining the pole orientation. This allowed us to derive the orbital
  elements of Kleopatra's two moons. <BR /> Results: Using both archival
  astrometric data and new VLT/SPHERE observations (ESO LP 199.C-0074),
  we were able to identify the true periods of the moons, P<SUB>1</SUB> =
  (1.822359 ± 0.004156) d, P<SUB>2</SUB> = (2.745820 ± 0.004820) d. They
  orbit very close to the 3:2 mean-motion resonance, but their osculating
  eccentricities are too small compared to other perturbations (multipole,
  mutual), meaning that regular librations of the critical argument are
  not present. The resulting mass of Kleopatra, m<SUB>1</SUB> = (1.49 ±
  0.16) × 10<SUP>−12</SUP> M<SUB>⊙</SUB> or 2.97 × 10<SUP>18</SUP>
  kg, is significantly lower than previously thought. An implication
  explained in the accompanying paper is that (216) Kleopatra is a
  critically rotating body. <P />Based on observations made with ESO
  Telescopes at the La Silla Paranal Observatory under program 199.C-0074
  (PI Vernazza).

---------------------------------------------------------
Title: VizieR Online Data Catalog: (216) Kleopatra images (Marchis+,
    2021)
Authors: Marchis, F.; Jorda, L.; Vernazza, P.; Broz, M.; Hanus, J.;
   Ferrais, M.; Vachier, F.; Rambaux, N.; Marsset, M.; Viikinkoski, M.;
   Jehin, E.; Benseguane, S.; Podlewska-Gaca, E.; Carry, B.; Drouard,
   A.; Fauvaud, S.; Birlan, M.; Berthier, J.; Bartczak, P.; Dumas, C.;
   Dudzinski, G.; Durech, J.; Castillo-Rogez, J.; Cipriani, F.; Colas,
   F.; Fetick, R.; Fusco, T.; Grice, J.; Kryszczynska, A.; Lamy, P.;
   Marciniak, A.; Michalowski, T.; Michel, P.; Pajuelo, M.; Santana-Ros,
   T.; Tanga, P.; Vigan, A.; Witasse, O.; Yang, B.
2021yCat..36530057M    Altcode:
  Deconvolved direct imaging observations of Kleopatra using
  the MISTRAL algorithm and a generated PSF. <P />Those fits
  files are direct images of (216) Kleopatra system. The reduced
  images were further deconvolved with the Mistral algorithm
  (Fusco et al., 2003, in Proc. SPIE, Vol. 4839, Adaptive Optical
  System Technologies II, ed. P. L. Wizinowich &amp; D. Bonaccini,
  1065-1075), using a parametric point-spread function (Fetick et
  al., 2019A&amp;A...623A...6F, Cat. J/A+A/623/A6). <P />object.dat :
  ----------------------------------------------------------------------
  Planet Name H Diam e i a mag km deg AU
  ----------------------------------------------------------------------
  216 Kleopatra 7.15 135.1 0.25126552 13.116286 2.79243307 <P />(2
  data files).

---------------------------------------------------------
Title: Evidence for differentiation of the most primitive small bodies
Authors: Carry, B.; Vernazza, P.; Vachier, F.; Neveu, M.; Berthier,
   J.; Hanuš, J.; Ferrais, M.; Jorda, L.; Marsset, M.; Viikinkoski,
   M.; Bartczak, P.; Behrend, R.; Benkhaldoun, Z.; Birlan, M.;
   Castillo-Rogez, J.; Cipriani, F.; Colas, F.; Drouard, A.; Dudziński,
   G. P.; Desmars, J.; Dumas, C.; Ďurech, J.; Fetick, R.; Fusco, T.;
   Grice, J.; Jehin, E.; Kaasalainen, M.; Kryszczynska, A.; Lamy, P.;
   Marchis, F.; Marciniak, A.; Michalowski, T.; Michel, P.; Pajuelo, M.;
   Podlewska-Gaca, E.; Rambaux, N.; Santana-Ros, T.; Storrs, A.; Tanga,
   P.; Vigan, A.; Warner, B.; Wieczorek, M.; Witasse, O.; Yang, B.
2021A&A...650A.129C    Altcode: 2021arXiv210306349C
  Context. Dynamical models of Solar System evolution have suggested
  that the so-called P- and D-type volatile-rich asteroids formed in
  the outer Solar System beyond Neptune's orbit and may be genetically
  related to the Jupiter Trojans, comets, and small Kuiper belt objects
  (KBOs). Indeed, the spectral properties of P- and D-type asteroids
  resemble that of anhydrous cometary dust. <BR /> Aims: We aim to
  gain insights into the above classes of bodies by characterizing the
  internal structure of a large P- and D-type asteroid. <BR /> Methods:
  We report high-angular-resolution imaging observations of the P-type
  asteroid (87) Sylvia with the Very Large Telescope Spectro-Polarimetric
  High-contrast Exoplanet REsearch (SPHERE) instrument. These images were
  used to reconstruct the 3D shape of Sylvia. Our images together with
  those obtained in the past with large ground-based telescopes were
  used to study the dynamics of its two satellites. We also modeled
  Sylvia's thermal evolution. <BR /> Results: The shape of Sylvia
  appears flattened and elongated (a/b ~1.45; a/c ~1.84). We derive a
  volume-equivalent diameter of 271 ± 5 km and a low density of 1378 ±
  45 kg m<SUP>−3</SUP>. The two satellites orbit Sylvia on circular,
  equatorial orbits. The oblateness of Sylvia should imply a detectable
  nodal precession which contrasts with the fully-Keplerian dynamics of
  its two satellites. This reveals an inhomogeneous internal structure,
  suggesting that Sylvia is differentiated. <BR /> Conclusions: Sylvia's
  low density and differentiated interior can be explained by partial
  melting and mass redistribution through water percolation. The outer
  shell should be composed of material similar to interplanetary dust
  particles (IDPs) and the core should be similar to aqueously altered
  IDPs or carbonaceous chondrite meteorites such as the Tagish Lake
  meteorite. Numerical simulations of the thermal evolution of Sylvia
  show that for a body of such a size, partial melting was unavoidable
  due to the decay of long-lived radionuclides. In addition, we show
  that bodies as small as 130-150 km in diameter should have followed a
  similar thermal evolution, while smaller objects, such as comets and the
  KBO Arrokoth, must have remained pristine, which is in agreement with
  in situ observations of these bodies. NASA Lucy mission target (617)
  Patroclus (diameter ≈140 km) may, however, be differentiated. <P
  />Tables A.1, B.1, C.1 and C.2 and the reduced and deconvolved
  SPHERE images are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/650/A129">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/650/A129</A>
  <P />Based on observations made with ESO telescopes
  at the La Silla Paranal Observatory under program <A
  href="http://archive.eso.org/wdb/wdb/eso/sched_rep_arc/query?progid=073.C-0851">073.C-0851</A>
  (PI Merline), <A
  href="http://archive.eso.org/wdb/wdb/eso/sched_rep_arc/query?progid=073.C-0062">073.C-0062</A>
  (PI Marchis), <A
  href="http://archive.eso.org/wdb/wdb/eso/sched_rep_arc/query?progid=085.C-0480">085.C-0480</A>
  (PI Nitschelm), <A
  href="http://archive.eso.org/wdb/wdb/eso/sched_rep_arc/query?progid=088.C-0528">088.C-0528</A>
  (PI Rojo), <A
  href="http://archive.eso.org/wdb/wdb/eso/sched_rep_arc/query?progid=199.C-0074">199.C-0074</A>
  (PI Vernazza).

---------------------------------------------------------
Title: Response of the interplanetary hydrogen population to global
changes of solar activity: a quantitative analysis based on SOHO/SWAN
    and SOHO/LASCO-C2 data comparison.
Authors: Koutroumpa, Dimitra; Quémerais, Eric; Conan, Lucile; Lamy,
   Philippe; Ferron, Stéphane; Gilardy, Hugo
2021EGUGA..23.9506K    Altcode:
  For more than two decades the SOHO/SWAN instrument has been monitoring
  the full-sky hydrogen backscattered Lyman-α emission, and the derived
  three-dimensional solar wind proton flux. We present a comparison of the
  time series of the latitude-integrated hydrogen ionization rates (β)
  derived from the inversion of the SWAN full-sky maps with the integrated
  coronal electron density derived from the inversion of SOHO/LASCO-C2
  white light images. The analysis shows a variable time lag of the SWAN
  β of a few Carrington rotations, correlated with the solar cycle phase
  (larger delay during solar maxima compared to minima). This is a direct
  consequence of the variation of the size of the hydrogen ionization
  cavity and the time it takes for hydrogen atoms to propagate in the
  inner heliosphere. This effect should be taken into account in studies
  of the interstellar neutral populations in interplanetary space.

---------------------------------------------------------
Title: LASCO-C3 Observations of the K- and F-Coronae over 24 Years
(1996 - 2019): Photopolarimetry and Electron Density Distribution
Authors: Lamy, Philippe; Gilardy, Hugo; Llebaria, Antoine; Quémerais,
   Eric; Ernandez, Fabrice
2021SoPh..296...76L    Altcode:
  We present the polarimetric analysis of the white-light images of the
  corona obtained with the Large-Angle Spectrometric COronagraph LASCO-C3
  onboard the Solar and Heliospheric Observatory (SOHO) from 1996 to
  2019, leading to the separation of the K- and F-components and the
  derivation of the electron-density distribution. The analysis makes
  use of polarized sequences composed of three images obtained through
  three polarizers oriented at +60<SUP>∘</SUP>, 0<SUP>∘</SUP>,
  and −60<SUP>∘</SUP>, complemented by a neighboring unpolarized
  image. However, the degradation of the 0<SUP>∘</SUP> polarizer
  noticed in 1999 compelled us to reconstruct the corresponding images
  from those obtained with the two other polarizers and the unpolarized
  ones thereafter. The analysis closely follows the method developed for
  LASCO-C2 (Lamy et al. in Solar Phys.295, 89, 2020) and implements the
  formalism of Mueller, albeit with additional difficulties notably the
  presence of a non-axially symmetric component of stray light. Critical
  corrections were derived from a SOHO roll sequence and from consistency
  criteria (e.g. the "tangential" direction of polarization). The
  quasi-uninterrupted photopolarimetric analysis of the outer corona
  over two complete Solar Cycles 23 and 24 was successfully achieved and
  our final results encompass the characterization of its polarization,
  of its polarized radiance, of the two-dimensional electron density,
  and of the K-corona. Comparison between the C3 and C2 results in
  the region where their fields of view overlap shows an overall
  agreement. The C3 results are further in agreement with those of
  eclipses and radio-ranging measurements to an elongation of ≈10
  R<SUB>⊙</SUB> but tend to diverge further out. Although the coronal
  polarization out to 20 R<SUB>⊙</SUB> is still highly correlated with
  the temporal variation of the total magnetic field, this divergence
  probably results from the increasing polarization of the F-corona with
  increasing solar elongation.

---------------------------------------------------------
Title: Restoration of the K and F Components of the Solar Corona
    from LASCO-C2 Images over 24 Years [1996 - 2019]
Authors: Llebaria, Antoine; Lamy, Philippe; Gilardy, Hugo; Boclet,
   Brice; Loirat, Jean
2021SoPh..296...53L    Altcode: 2020arXiv201112920L
  We present a photometrically accurate restoration of the K- and
  F-coronae from white-light images obtained over 24 years [1996 - 2019]
  by the Large-Angle Spectrometric COronagraph (LASCO-C2) onboard the
  Solar and Heliospheric Observatory (SOHO). The procedure starts with
  the data set of unpolarized images of 512 × 512 pixels produced by
  the polarimetric analysis of the routine C2 polarization sequences
  (Lamy et al., Solar Phys.295, 89, 2020) in which the F-corona, the
  instrumental stray light, and possible remnants of the K-corona due to
  the imperfect polarimetric separation are entangled. Disentangling these
  components requires a complex procedure organized in three stages,
  each composed of several steps. Stage 1 establishes the distinct
  variations of the radiance of these components with the Sun-SOHO
  distance, and generate a new data set of median images calculated for
  each Carrington rotation. Stage 2 achieves the restoration of a set of
  36 stray-light images that account for the temporal variation of the
  stray-light pattern, in particular those associated with the periodic
  roll maneuvers of SOHO, which started in 2003. Stage 3 achieves the
  restoration of the F-corona, and a time series of daily images is
  generated. Combining these images with the set of stray-light images
  allowed us to process the whole set of routine LASCO-C2 images of 1024
  × 1024 pixels (approximately 626,000 images) and to produce calibrated,
  high-resolution images of the K-corona. The two sets of images of the
  K-corona, that produced by polarimetric separation of 512 × 512 pixels
  images and that presently produced by subtraction, are in excellent
  photometric agreement. We extend our past conclusions that the temporal
  variation of the integrated radiance of the K-corona tracks the solar
  activity over Solar Cycles 23 and 24, and that it is highly correlated
  with the temporal variation of the total magnetic field. The behaviors
  of the integrated radiance during the last few years of the declining
  phases of Solar Cycles 23 and 24 are remarkably similar, reaching the
  same base level and leading to a duration of 11.0 years for the latter
  cycle, in agreement with that derived from sunspots.

---------------------------------------------------------
Title: VizieR Online Data Catalog: SPHERE (87) Sylvia images
    (Carry+, 2021)
Authors: Carry, B.; Vernazza, P.; Vachier, F.; Neveu, M.; Berthier,
   J.; Hanus, J.; Ferrais, M.; Jorda, L.; Marsset, M.; Viikinkoski, M.;
   Bartczak, P.; Behrend, R.; Benkhaldoun, Z.; Birlan, M.; Castillo-Rogez,
   J.; Cipriani, F.; Colas, F.; Drouard, A.; Dudzinski, G. P.; Desmars,
   J.; Dumas, J.; Durech, C.; Fetick, R.; Fusco, T.; Grice, J.; Jehin, E.;
   Kaasalainen, M.; Kryszczynska, A.; Lamy, P.; Marchis, F.; Marciniak,
   A.; Michalowski, T.; Michel, P.; Pajuelo, M.; Podlewska-Gaca, E.;
   Rambaux, N.; Santana-Ros, T.; Storrs, A.; Tanga, P.; Vigan, A.;
   Warner, B.; Wieczorek, M.; Witasse, O.; Yang, B.
2021yCat..36500129C    Altcode:
  Sylvia was observed with the SPHERE instrument (ESO/VLT) around its
  opposition at eleven different epochs. We used IRDIS in broad band
  (Y filter; filter central wavelength 1041.4nm, width = 135.2nm)
  and ZIMPOL in narrowband imaging mode (N_R filter; filter central
  wavelength = 645.9nm, width = 56.7nm). <P />Each observational sequence
  consisted of a series of images, where each image corresponded to
  a series of detector integration times (DITs) of 10s, during which
  Sylvia was used as a natural guide star for adaptive optics (AO)
  corrections. Observations were performed under good seeing conditions
  (&lt;=0.8") with an airmass usually below 1.6. Standard calibrations,
  which include detector flat-fields and darks, were acquired in the
  morning as part of the instrument calibration plan. <P />objects:
  -------------------------------------------------------------------
  Planet Name H Diam i e a mag km deg AU
  -------------------------------------------------------------------
  87 Sylvia 6.86 261.0 10.87567 0.09351718 3.48178042
  -------------------------------------------------------------------
  <P />(6 data files).

---------------------------------------------------------
Title: Three-Dimensional Tomographic Reconstruction and MHD Modeling
of the Solar Corona and Wind: WHPI Campaign Rotations CR-2219
    and CR-2223
Authors: Lloveras, D.; Vásquez, A. M.; Nuevo, F.; Sachdeva, N.;
   Manchester, W.; van der Holst, B.; Frazin, R. A.; Lamy, P.; Wojak, J.
2020AGUFMSH021..07L    Altcode:
  Accurate prediction of space weather conditions requires
  state-of-the-art three-dimensional (3D) magnetohydrodynamic (MHD)
  models, which need to be validated with observational data. The recent
  deep minimum of solar activity, between solar cycles 24 and 25, renews
  the opportunity to study the Sun-Earth connection under the simplest
  solar and space environmental conditions. The international Whole
  Heliosphere and Planetary Interactions (WHPI) initiative aims at this
  specific purpose. In this work, we study two WHPI campaign periods,
  the July 2019 total solar eclipse Carrington rotation (CR)-2019, and
  the Parker Solar Probe and STEREO-A closest approach CR-2223. Based
  on narrowband EUV data provided by the SDO/AIA instrument we carry
  out tomographic reconstruction of the coronal electron density
  and temperature in the range of heliocentric heights r ≤ 1.25
  R<SUB>sun</SUB>. Based on visible light coronagraph data provided by
  the SoHO/LASCO-C2 instrument we carry out tomographic reconstruction of
  the coronal electron density and in the range of heliocentric heights
  ≈ 2.5-6.0 R<SUB>sun</SUB>. Applying ADAPT-GONG synoptic magnetograms
  as boundary conditions, we use the Alfven Wave Solar Model (AWSoM)
  to simulate the corona and solar wind for these time periods. We
  study the capability of the 3D-MHD model to reproduce the tomographic
  reconstructions in both closed and open coronal magnetic structures. In
  coronal holes in particular, we investigate the correlation between
  the reconstructed 3D distribution of the thermodynamical properties
  in the low corona and the 3D distribution of the physical parameters
  of the terminal solar wind of the model, discriminating its fast and
  slow components

---------------------------------------------------------
Title: Volume uncertainty of (7) Iris shape models from disc-resolved
    images
Authors: Dudziński, G.; Podlewska-Gaca, E.; Bartczak, P.; Benseguane,
   S.; Ferrais, M.; Jorda, L.; Hanuš, J.; Vernazza, P.; Rambaux,
   N.; Carry, B.; Marchis, F.; Marsset, M.; Viikinkoski, M.; Brož,
   M.; Fetick, R.; Drouard, A.; Fusco, T.; Birlan, M.; Jehin, E.;
   Berthier, J.; Castillo-Rogez, J.; Cipriani, F.; Colas, F.; Dumas,
   C.; Kryszczynska, A.; Lamy, P.; Le Coroller, H.; Marciniak, A.;
   Michalowski, T.; Michel, P.; Santana-Ros, T.; Tanga, P.; Vachier,
   F.; Vigan, A.; Witasse, O.; Yang, B.
2020MNRAS.499.4545D    Altcode: 2020MNRAS.tmp.2956D
  High angular resolution disc-resolved images of (7) Iris collected by
  VLT/SPHERE instrument are allowed for the detailed shape modelling of
  this large asteroid revealing its surface features. If (7) Iris did
  not suffer any events catastrophic enough to disrupt the body (which
  is very likely) by studying its topography, we might get insights
  into the early Solar system's collisional history. When it comes to
  internal structure and composition, thoroughly assessing the volume and
  density uncertainties is necessary. In this work, we propose a method
  of uncertainty calculation of asteroid shape models based on light
  curve and adaptive optics (AO) images. We apply this method on four
  models of (7) Iris produced from independent Shaping Asteroids using
  Genetic Evolution and All-Data Asteroid Modelling inversion techniques
  and multiresolution photoclinometry by deformation. Obtained diameter
  uncertainties stem from both the observations from which the models were
  scaled and the models themselves. We show that despite the availability
  of high-resolution AO images, the volume and density of (7) Iris have
  substantial error bars that were underestimated in the previous studies.

---------------------------------------------------------
Title: The Solar Orbiter Heliospheric Imager (SoloHI)
Authors: Howard, R. A.; Vourlidas, A.; Colaninno, R. C.; Korendyke,
   C. M.; Plunkett, S. P.; Carter, M. T.; Wang, D.; Rich, N.; Lynch,
   S.; Thurn, A.; Socker, D. G.; Thernisien, A. F.; Chua, D.; Linton,
   M. G.; Koss, S.; Tun-Beltran, S.; Dennison, H.; Stenborg, G.; McMullin,
   D. R.; Hunt, T.; Baugh, R.; Clifford, G.; Keller, D.; Janesick, J. R.;
   Tower, J.; Grygon, M.; Farkas, R.; Hagood, R.; Eisenhauer, K.; Uhl,
   A.; Yerushalmi, S.; Smith, L.; Liewer, P. C.; Velli, M. C.; Linker,
   J.; Bothmer, V.; Rochus, P.; Halain, J. -P.; Lamy, P. L.; Auchère,
   F.; Harrison, R. A.; Rouillard, A.; Patsourakos, S.; St. Cyr, O. C.;
   Gilbert, H.; Maldonado, H.; Mariano, C.; Cerullo, J.
2020A&A...642A..13H    Altcode:
  <BR /> Aims: We present the design and pre-launch performance of
  the Solar Orbiter Heliospheric Imager (SoloHI) which is an instrument
  prepared for inclusion in the ESA/NASA Solar Orbiter mission, currently
  scheduled for launch in 2020. <BR /> Methods: The goal of this paper
  is to provide details of the SoloHI instrument concept, design, and
  pre-flight performance to give the potential user of the data a better
  understanding of how the observations are collected and the sources
  that contribute to the signal. <BR /> Results: The paper discusses
  the science objectives, including the SoloHI-specific aspects, before
  presenting the design concepts, which include the optics, mechanical,
  thermal, electrical, and ground processing. Finally, a list of planned
  data products is also presented. <BR /> Conclusions: The performance
  measurements of the various instrument parameters meet or exceed the
  requirements derived from the mission science objectives. SoloHI is
  poised to take its place as a vital contributor to the science success
  of the Solar Orbiter mission.

---------------------------------------------------------
Title: Metis: the Solar Orbiter visible light and ultraviolet
    coronal imager
Authors: Antonucci, Ester; Romoli, Marco; Andretta, Vincenzo; Fineschi,
   Silvano; Heinzel, Petr; Moses, J. Daniel; Naletto, Giampiero; Nicolini,
   Gianalfredo; Spadaro, Daniele; Teriaca, Luca; Berlicki, Arkadiusz;
   Capobianco, Gerardo; Crescenzio, Giuseppe; Da Deppo, Vania; Focardi,
   Mauro; Frassetto, Fabio; Heerlein, Klaus; Landini, Federico; Magli,
   Enrico; Marco Malvezzi, Andrea; Massone, Giuseppe; Melich, Radek;
   Nicolosi, Piergiorgio; Noci, Giancarlo; Pancrazzi, Maurizio; Pelizzo,
   Maria G.; Poletto, Luca; Sasso, Clementina; Schühle, Udo; Solanki,
   Sami K.; Strachan, Leonard; Susino, Roberto; Tondello, Giuseppe;
   Uslenghi, Michela; Woch, Joachim; Abbo, Lucia; Bemporad, Alessandro;
   Casti, Marta; Dolei, Sergio; Grimani, Catia; Messerotti, Mauro;
   Ricci, Marco; Straus, Thomas; Telloni, Daniele; Zuppella, Paola;
   Auchère, Frederic; Bruno, Roberto; Ciaravella, Angela; Corso,
   Alain J.; Alvarez Copano, Miguel; Aznar Cuadrado, Regina; D'Amicis,
   Raffaella; Enge, Reiner; Gravina, Alessio; Jejčič, Sonja; Lamy,
   Philippe; Lanzafame, Alessandro; Meierdierks, Thimo; Papagiannaki,
   Ioanna; Peter, Hardi; Fernandez Rico, German; Giday Sertsu, Mewael;
   Staub, Jan; Tsinganos, Kanaris; Velli, Marco; Ventura, Rita; Verroi,
   Enrico; Vial, Jean-Claude; Vives, Sebastien; Volpicelli, Antonio;
   Werner, Stephan; Zerr, Andreas; Negri, Barbara; Castronuovo, Marco;
   Gabrielli, Alessandro; Bertacin, Roberto; Carpentiero, Rita; Natalucci,
   Silvia; Marliani, Filippo; Cesa, Marco; Laget, Philippe; Morea, Danilo;
   Pieraccini, Stefano; Radaelli, Paolo; Sandri, Paolo; Sarra, Paolo;
   Cesare, Stefano; Del Forno, Felice; Massa, Ernesto; Montabone, Mauro;
   Mottini, Sergio; Quattropani, Daniele; Schillaci, Tiziano; Boccardo,
   Roberto; Brando, Rosario; Pandi, Arianna; Baietto, Cristian; Bertone,
   Riccardo; Alvarez-Herrero, Alberto; García Parejo, Pilar; Cebollero,
   María; Amoruso, Mauro; Centonze, Vito
2020A&A...642A..10A    Altcode: 2019arXiv191108462A
  <BR /> Aims: Metis is the first solar coronagraph designed for a
  space mission and is capable of performing simultaneous imaging of the
  off-limb solar corona in both visible and UV light. The observations
  obtained with Metis aboard the Solar Orbiter ESA-NASA observatory
  will enable us to diagnose, with unprecedented temporal coverage and
  spatial resolution, the structures and dynamics of the full corona
  in a square field of view (FoV) of ±2.9° in width, with an inner
  circular FoV at 1.6°, thus spanning the solar atmosphere from 1.7
  R<SUB>⊙</SUB> to about 9 R<SUB>⊙</SUB>, owing to the eccentricity
  of the spacecraft orbit. Due to the uniqueness of the Solar Orbiter
  mission profile, Metis will be able to observe the solar corona
  from a close (0.28 AU, at the closest perihelion) vantage point,
  achieving increasing out-of-ecliptic views with the increase of the
  orbit inclination over time. Moreover, observations near perihelion,
  during the phase of lower rotational velocity of the solar surface
  relative to the spacecraft, allow longer-term studies of the off-limb
  coronal features, thus finally disentangling their intrinsic evolution
  from effects due to solar rotation. <BR /> Methods: Thanks to a novel
  occultation design and a combination of a UV interference coating of
  the mirrors and a spectral bandpass filter, Metis images the solar
  corona simultaneously in the visible light band, between 580 and 640
  nm, and in the UV H I Lyman-α line at 121.6 nm. The visible light
  channel also includes a broadband polarimeter able to observe the
  linearly polarised component of the K corona. The coronal images in
  both the UV H I Lyman-α and polarised visible light are obtained at
  high spatial resolution with a spatial scale down to about 2000 km
  and 15 000 km at perihelion, in the cases of the visible and UV light,
  respectively. A temporal resolution down to 1 s can be achieved when
  observing coronal fluctuations in visible light. <BR /> Results: The
  Metis measurements, obtained from different latitudes, will allow for
  complete characterisation of the main physical parameters and dynamics
  of the electron and neutral hydrogen/proton plasma components of the
  corona in the region where the solar wind undergoes the acceleration
  process and where the onset and initial propagation of coronal mass
  ejections (CMEs) take place. The near-Sun multi-wavelength coronal
  imaging performed with Metis, combined with the unique opportunities
  offered by the Solar Orbiter mission, can effectively address crucial
  issues of solar physics such as: the origin and heating/acceleration
  of the fast and slow solar wind streams; the origin, acceleration,
  and transport of the solar energetic particles; and the transient
  ejection of coronal mass and its evolution in the inner heliosphere,
  thus significantly improving our understanding of the region connecting
  the Sun to the heliosphere and of the processes generating and driving
  the solar wind and coronal mass ejections. <BR /> Conclusions: This
  paper presents the scientific objectives and requirements, the overall
  optical design of the Metis instrument, the thermo-mechanical design,
  and the processing and power unit; reports on the results of the
  campaigns dedicated to integration, alignment, and tests, and to
  the characterisation of the instrument performance; describes the
  operation concept, data handling, and software tools; and, finally,
  the diagnostic techniques to be applied to the data, as well as a brief
  description of the expected scientific products. The performance of the
  instrument measured during calibrations ensures that the scientific
  objectives of Metis can be pursued with success. <P />Metis website:
  <A href="http://metis.oato.inaf.it">http://metis.oato.inaf.it</A>

---------------------------------------------------------
Title: Coronal Photopolarimetry with the LASCO-C3 Coronagraph over
    24 Years [1996-2019] -- Application to the K/F Separation and to
    the Determination of the Electron Density
Authors: Lamy, Philippe; Gilardy, Hugo; Llebaria, Antoine; Quemerais,
   Eric; Ernandes, Fabrice
2020arXiv200904820L    Altcode:
  We present an in-depth characterization of the polarimetric channel of
  the Large-Angle Spectrometric COronagraph/LASCO-C3 onboard SOHO. The
  polarimetric analysis of the white-light images makes use of polarized
  sequences composed of three images obtained through three polarizers
  oriented at +60$^\circ$, 0$^\circ$, and -60$^\circ$, complemented by a
  neighboring unpolarized image. However, the degradation of the 0$^\circ$
  polarizer noticed in 1999 compelled us to reconstruct the corresponding
  images from the other ones thereafter. The analysis closely follows the
  method developed for LASCO-C2 (Lamy, et al. Solar Physics 295, 89, 2020
  and arXiv:2001.05925) and implements the formalism of Mueller, albeit
  with additional difficulties notably the presence of a non-axially
  symmetric component of stray light. Critical corrections were derived
  from a SOHO roll sequence and from consistency criteria (e.g.,
  the tangential direction of polarization). The quasi-uninterrupted
  photopolarimetric analysis of the outer corona over two complete
  Solar Cycles 23 and 24 was successfully achieved and our final
  results encompass the characterization of its polarization, of its
  polarized radiance, of the two-dimensional electron density, and of the
  K-corona. Comparison between the C3 and C2 results where their field of
  view overlaps shows an overall agreement. The C3 results are further
  in agreement with those of eclipses and radio ranging measurements
  to an elongation of about 10 solar radii but tend to diverge further
  out. Whereas the coronal polarization out to 20 solar radii is still
  highly correlated with the temporal variation of the total magnetic
  field, this divergence probably results from the increasing polarization
  of the F-corona.

---------------------------------------------------------
Title: Binary asteroid (31) Euphrosyne: ice-rich and nearly spherical
Authors: Yang, B.; Hanuš, J.; Carry, B.; Vernazza, P.; Brož, M.;
   Vachier, F.; Rambaux, N.; Marsset, M.; Chrenko, O.; Ševeček, P.;
   Viikinkoski, M.; Jehin, E.; Ferrais, M.; Podlewska-Gaca, E.; Drouard,
   A.; Marchis, F.; Birlan, M.; Benkhaldoun, Z.; Berthier, J.; Bartczak,
   P.; Dumas, C.; Dudziński, G.; Ďurech, J.; Castillo-Rogez, J.;
   Cipriani, F.; Colas, F.; Fetick, R.; Fusco, T.; Grice, J.; Jorda,
   L.; Kaasalainen, M.; Kryszczynska, A.; Lamy, P.; Marciniak, A.;
   Michalowski, T.; Michel, P.; Pajuelo, M.; Santana-Ros, T.; Tanga,
   P.; Vigan, A.; Witasse, O.
2020A&A...641A..80Y    Altcode: 2020arXiv200708059Y
  <BR /> Aims: Asteroid (31) Euphrosyne is one of the biggest objects in
  the asteroid main belt and it is also the largest member of its namesake
  family. The Euphrosyne family occupies a highly inclined region in the
  outer main belt and contains a remarkably large number of members, which
  is interpreted as an outcome of a disruptive cratering event. <BR />
  Methods: The goals of this adaptive-optics imaging study are threefold:
  to characterize the shape of Euphrosyne, to constrain its density, and
  to search for the large craters that may be associated with the family
  formation event. <BR /> Results: We obtained disk-resolved images of
  Euphrosyne using SPHERE/ZIMPOL at the ESO 8.2 m VLT as part of our large
  program (ID: 199.C-0074, PI: Vernazza). We reconstructed its 3D shape
  via the ADAM shape modeling algorithm based on the SPHERE images and
  the available light curves of this asteroid. We analyzed the dynamics
  of the satellite with the Genoid meta-heuristic algorithm. Finally,
  we studied the shape of Euphrosyne using hydrostatic equilibrium
  models. <BR /> Conclusions: Our SPHERE observations show that Euphrosyne
  has a nearly spherical shape with the sphericity index of 0.9888 and
  its surface lacks large impact craters. Euphrosyne's diameter is 268
  ± 6 km, making it one of the top ten largest main belt asteroids. We
  detected a satellite of Euphrosyne - S/2019 (31) 1 - that is about 4
  km across, on a circular orbit. The mass determined from the orbit
  of the satellite together with the volume computed from the shape
  model imply a density of 1665 ± 242 kg m<SUP>-3</SUP>, suggesting
  that Euphrosyne probably contains a large fraction of water ice in its
  interior. We find that the spherical shape of Euphrosyne is a result of
  the reaccumulation process following the impact, as in the case of (10)
  Hygiea. However, our shape analysis reveals that, contrary to Hygiea,
  the axis ratios of Euphrosyne significantly differ from those suggested
  by fluid hydrostatic equilibrium following reaccumulation. <P />The
  reduced images are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/641/A80">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/641/A80</A>
  <P />Based on observations made with ESO Telescopes at the La Silla
  Paranal Observatory under program 199.C-0074 (PI Vernazza).

---------------------------------------------------------
Title: VizieR Online Data Catalog: Asteroid (31) Euphrosyne R-band
    images (Yang+, 2020)
Authors: Yang, B.; Hanus, J.; Carry, B.; Vernazza, P.; Broz,
   M.; Vachier, F.; Rambaux, N.; Marsset, M.; Chrenko, O.; Sevecek,
   P.; Viikinkoski, M.; Jehin, E.; Ferrais, M.; Podlewska-Gaca, E.;
   Drouard, A.; Marchis, F.; Birlan, M.; Benkhaldoun, Z.; Berthier, J.;
   Bartczak, P.; Dumas, C.; Dudzinski, G.; Durech, J.; Castillo-Rogez,
   J.; Cipriani, F.; Colas, F.; Fetick, R.; Fusco, T.; Grice, J.;
   Jorda, L.; Kaasalainen, M.; Kryszczynska, A.; Lamy, P.; Marciniak,
   A.; Michalowski, T.; Michel, P.; Pajuelo, M.; Santana-Ros, T.; Tanga,
   P.; Vigan, A.; Witasse, O.
2020yCat..36410080Y    Altcode:
  Euphrosyne was observed, between March and April 2019 (2019-03-15,
  2019-03-20, 2019-03-25, 2019-03-27, 2019-04-10), using the Zurich
  Imaging Polarimeter (ZIMPOL) of SPHERE in the direct imaging mode with
  the narrow band filter (N_R filter; filter central wavelength=645.9nm,
  width=56.7nm). <P />(2 data files).

---------------------------------------------------------
Title: Coronal Photopolarimetry with the LASCO-C2 Coronagraph over
    24 Years [1996 - 2019]
Authors: Lamy, Philippe; Llebaria, Antoine; Boclet, Brice; Gilardy,
   Hugo; Burtin, Michael; Floyd, Olivier
2020SoPh..295...89L    Altcode: 2020arXiv200105925L
  We present an in-depth characterization of the polarimetric channel of
  the Large-Angle Spectrometric COronagraph/LASCO-C2 onboard the Solar
  and Heliospheric Observatory (SOHO). The polarimetric analysis of the
  white-light images makes use of polarized sequences composed of three
  images obtained though three polarizers oriented at +60<SUP>∘</SUP>,
  0<SUP>∘</SUP>, and −60<SUP>∘</SUP>, complemented by a neighboring
  unpolarized image, and relies on the formalism of Mueller. The
  Mueller matrix characterizing the C2 instrument was obtained through
  extensive ground-based calibrations of the optical components and
  global laboratory tests. Additional critical corrections were derived
  from in-flight tests relying prominently on roll sequences of SOHO, on
  the basis of consistency criteria (e.g. the "tangential" direction of
  polarization), and from several applications, notably the time-dependent
  tomographic reconstruction of the coronal electron density. This
  took several years of effort, but resulted in the quasi-uninterrupted
  photopolarimetric analysis of the corona over two complete Solar Cycles
  23 and 24, and the comparison with a variety of eclipse data obtained
  at different phases of these cycles. Our final results encompass
  the characterization of the polarization of the white-light corona,
  of its polarized radiance, of the two-dimensional electron density,
  and of the K-corona. The agreement with the eclipse data is excellent
  except for slight discrepancies affecting the innermost part of the C2
  field of view. The present work leaves the two unpolarized components,
  F-corona and stray light, entangled and their complex separation will
  be dealt with in a follow-on article.

---------------------------------------------------------
Title: VizieR Online Data Catalog: (16) Psyche. VLT/SPHERE images
    and shape models (Ferrais+, 2020)
Authors: Ferrais, M.; Vernazza, P.; Jorda, L.; Rambaux, N.; Hanu,
   J.; Carry, B.; Marchis, F.; Marsset, M.; Viikinkoski, M.; Broz, M.;
   Fetick, R.; Drouard, A.; Fusco, T.; Birlan, M.; Podlewska-Gaca, E.;
   Jehin, E.; Bartczak, P.; Berthier, J.; Castillo-Rogez, J.; Cipriani,
   F.; Colas, F.; Dudzinski, G.; Dumas, C.; Durech, J.; Kaasalainen,
   M.; Kryszczynska, A.; Lamy, P.; Le Coroller, H.; Marciniak, A.;
   Michalowski, T.; Michel, P.; Santana-Ros, T.; Tanga, P.; Vachier,
   F.; Vigan, A.; Witasse, O.; Yang, B.
2020yCat..36389015F    Altcode:
  We obtained 35 images of Psyche at 7 epochs in July and August 2019
  using VLT/SPHERE/ZIMPOL. This data set complements the first 25 images
  taken within our ESO large program that was already presented in
  Viikinkoski et al. (2018A&amp;A...619L...3V), for a total of 60 images
  taken at 12 epochs. All images were reduced following the procedure
  described in Vernazza et al. (2018A&amp;A...618A.154V). <P />object:
  -------------------------------------------------------------------
  Planet Name H Diam i e a mag km deg AU
  -------------------------------------------------------------------
  16 Psyche 5.90 222.0 3.096560 0.13353119 2.92277557
  ------------------------------------------------------------------
  <P />(8 data files).

---------------------------------------------------------
Title: Asteroid (16) Psyche's primordial shape: A possible Jacobi
    ellipsoid
Authors: Ferrais, M.; Vernazza, P.; Jorda, L.; Rambaux, N.; Hanuš,
   J.; Carry, B.; Marchis, F.; Marsset, M.; Viikinkoski, M.; Brož, M.;
   Fetick, R.; Drouard, A.; Fusco, T.; Birlan, M.; Podlewska-Gaca, E.;
   Jehin, E.; Bartczak, P.; Berthier, J.; Castillo-Rogez, J.; Cipriani,
   F.; Colas, F.; Dudziński, G.; Dumas, C.; Ďurech, J.; Kaasalainen,
   M.; Kryszczynska, A.; Lamy, P.; Le Coroller, H.; Marciniak, A.;
   Michalowski, T.; Michel, P.; Santana-Ros, T.; Tanga, P.; Vachier,
   F.; Vigan, A.; Witasse, O.; Yang, B.
2020A&A...638L..15F    Altcode:
  Context. Asteroid (16) Psyche is the largest M-type asteroid in the
  main belt and the target of the NASA Psyche mission. It is also the only
  asteroid of this size (D &gt; 200 km) known to be metal rich. Although
  various hypotheses have been proposed to explain the rather unique
  physical properties of this asteroid, a perfect understanding of
  its formation and bulk composition is still missing. <BR /> Aims:
  We aim to refine the shape and bulk density of (16) Psyche and to
  perform a thorough analysis of its shape to better constrain possible
  formation scenarios and the structure of its interior. <BR /> Methods:
  We obtained disk-resolved VLT/SPHERE/ZIMPOL images acquired within
  our ESO large program (ID 199.C-0074), which complement similar
  data obtained in 2018. Both data sets offer a complete coverage
  of Psyche's surface. These images were used to reconstruct the
  three-dimensional (3D) shape of Psyche with two independent shape
  modeling algorithms (MPCD and ADAM). A shape analysis was subsequently
  performed, including a comparison with equilibrium figures and the
  identification of mass deficit regions. <BR /> Results: Our 3D shape
  along with existing mass estimates imply a density of 4.20 ± 0.60
  g cm<SUP>-3</SUP>, which is so far the highest for a solar system
  object following the four telluric planets. Furthermore, the shape
  of Psyche presents small deviations from an ellipsoid, that is,
  prominently three large depressions along its equator. The flatness
  and density of Psyche are compatible with a formation at hydrostatic
  equilibrium as a Jacobi ellipsoid with a shorter rotation period of
  ∼3h. Later impacts may have slowed down Psyche's rotation, which is
  currently ∼4.2 h, while also creating the imaged depressions. <BR />
  Conclusions: Our results open the possibility that Psyche acquired
  its primordial shape either after a giant impact while its interior
  was already frozen or while its interior was still molten owing to
  the decay of the short-lived radionuclide <SUP>26</SUP>Al. <P />The
  reduced images are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr/">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/638/L15">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/638/L15</A>
  <P />Based on observations made with ESO Telescopes at the Paranal
  Observatory under programme ID 199.C-0074 (PI: P. Vernazza).

---------------------------------------------------------
Title: The violent collisional history of aqueously evolved (2) Pallas
Authors: Marsset, Michaël; Brož, Miroslav; Vernazza, Pierre; Drouard,
   Alexis; Castillo-Rogez, Julie; Hanuš, Josef; Viikinkoski, Matti;
   Rambaux, Nicolas; Carry, Benoît; Jorda, Laurent; Ševeček, Pavel;
   Birlan, Mirel; Marchis, Franck; Podlewska-Gaca, Edyta; Asphaug, Erik;
   Bartczak, Przemyslaw; Berthier, Jérôme; Cipriani, Fabrice; Colas,
   François; Dudziński, Grzegorz; Dumas, Christophe; Durech, Josef;
   Ferrais, Marin; Fétick, Romain; Fusco, Thierry; Jehin, Emmanuel;
   Kaasalainen, Mikko; Kryszczynska, Agnieszka; Lamy, Philippe; Le
   Coroller, Hervé; Marciniak, Anna; Michalowski, Tadeusz; Michel,
   Patrick; Richardson, Derek C.; Santana-Ros, Toni; Tanga, Paolo;
   Vachier, Frédéric; Vigan, Arthur; Witasse, Olivier; Yang, Bin
2020NatAs...4..569M    Altcode: 2020NatAs.tmp...24M
  Asteroid (2) Pallas is the largest main-belt object not yet visited by
  a spacecraft, making its surface geology largely unknown and limiting
  our understanding of its origin and collisional evolution. Previous
  ground-based observational campaigns returned different estimates
  of its bulk density that are inconsistent with one another, one
  measurement<SUP>1</SUP> being compatible within error bars with
  the icy Ceres (2.16 ± 0.01 g cm<SUP>-3</SUP>)<SUP>2</SUP> and
  the other<SUP>3</SUP> compatible within error bars with the rocky
  Vesta (3.46 ± 0.03 g cm<SUP>-3</SUP>)<SUP>4</SUP>. Here we report
  high-angular-resolution observations of Pallas performed with the
  extreme adaptive optics-fed SPHERE imager<SUP>5</SUP> on the Very
  Large Telescope. Pallas records a violent collisional history, with
  numerous craters larger than 30 km in diameter populating its surface
  and two large impact basins that could be related to a family-forming
  impact. Monte Carlo simulations of the collisional evolution of the
  main belt correlate this cratering record to the high average impact
  velocity of ~11.5 km s<SUP>-1</SUP> on Pallas—compared with an
  average of ~5.8 km s<SUP>-1</SUP> for the asteroid belt—induced by
  Pallas's high orbital inclination (i = 34.8°) and orbital eccentricity
  (e = 0.23). Compositionally, Pallas's derived bulk density of 2.89 ±
  0.08 g cm<SUP>-3</SUP> (1σ uncertainty) is fully compatible with a CM
  chondrite-like body, as suggested by its spectral reflectance in the 3
  μm wavelength region<SUP>6</SUP>. A bright spot observed on its surface
  may indicate an enrichment in salts during an early phase of aqueous
  alteration, compatible with Pallas's relatively high albedo of 12-17%
  (refs. <SUP>7,8</SUP>), although alternative origins are conceivable.

---------------------------------------------------------
Title: A basin-free spherical shape as an outcome of a giant impact
    on asteroid Hygiea
Authors: Vernazza, P.; Jorda, L.; Ševeček, P.; Brož, M.;
   Viikinkoski, M.; Hanuš, J.; Carry, B.; Drouard, A.; Ferrais, M.;
   Marsset, M.; Marchis, F.; Birlan, M.; Podlewska-Gaca, E.; Jehin,
   E.; Bartczak, P.; Dudzinski, G.; Berthier, J.; Castillo-Rogez, J.;
   Cipriani, F.; Colas, F.; DeMeo, F.; Dumas, C.; Durech, J.; Fetick,
   R.; Fusco, T.; Grice, J.; Kaasalainen, M.; Kryszczynska, A.; Lamy,
   P.; Le Coroller, H.; Marciniak, A.; Michalowski, T.; Michel, P.;
   Rambaux, N.; Santana-Ros, T.; Tanga, P.; Vachier, F.; Vigan, A.;
   Witasse, O.; Yang, B.; Gillon, M.; Benkhaldoun, Z.; Szakats, R.;
   Hirsch, R.; Duffard, R.; Chapman, A.; Maestre, J. L.
2020NatAs...4..136V    Altcode: 2019NatAs.tmp..477V
  (10) Hygiea is the fourth largest main belt asteroid and the only
  known asteroid whose surface composition appears similar to that of
  the dwarf planet (1) Ceres<SUP>1,2</SUP>, suggesting a similar origin
  for these two objects. Hygiea suffered a giant impact more than 2 Gyr
  ago<SUP>3</SUP> that is at the origin of one of the largest asteroid
  families. However, Hygeia has never been observed with sufficiently
  high resolution to resolve the details of its surface or to constrain
  its size and shape. Here, we report high-angular-resolution imaging
  observations of Hygiea with the VLT/SPHERE instrument (~20 mas
  at 600 nm) that reveal a basin-free nearly spherical shape with
  a volume-equivalent radius of 217 ± 7 km, implying a density of
  1,944 ± 250 kg m<SUP>-</SUP><SUP>3</SUP> to 1σ. In addition, we
  have determined a new rotation period for Hygiea of ~13.8 h, which
  is half the currently accepted value. Numerical simulations of the
  family-forming event show that Hygiea's spherical shape and family can
  be explained by a collision with a large projectile (diameter ~75-150
  km). By comparing Hygiea's sphericity with that of other Solar System
  objects, it appears that Hygiea is nearly as spherical as Ceres, opening
  up the possibility for this object to be reclassified as a dwarf planet.

---------------------------------------------------------
Title: (704) Interamnia: a transitional object between a dwarf planet
    and a typical irregular-shaped minor body
Authors: Hanuš, J.; Vernazza, P.; Viikinkoski, M.; Ferrais, M.;
   Rambaux, N.; Podlewska-Gaca, E.; Drouard, A.; Jorda, L.; Jehin,
   E.; Carry, B.; Marsset, M.; Marchis, F.; Warner, B.; Behrend, R.;
   Asenjo, V.; Berger, N.; Bronikowska, M.; Brothers, T.; Charbonnel,
   S.; Colazo, C.; Coliac, J. -F.; Duffard, R.; Jones, A.; Leroy, A.;
   Marciniak, A.; Melia, R.; Molina, D.; Nadolny, J.; Person, M.; Pejcha,
   O.; Riemis, H.; Shappee, B.; Sobkowiak, K.; Soldán, F.; Suys, D.;
   Szakats, R.; Vantomme, J.; Birlan, M.; Berthier, J.; Bartczak, P.;
   Dumas, C.; Dudziński, G.; Ďurech, J.; Castillo-Rogez, J.; Cipriani,
   F.; Fetick, R.; Fusco, T.; Grice, J.; Kaasalainen, M.; Kryszczynska,
   A.; Lamy, P.; Michalowski, T.; Michel, P.; Santana-Ros, T.; Tanga,
   P.; Vachier, F.; Vigan, A.; Witasse, O.; Yang, B.
2020A&A...633A..65H    Altcode: 2019arXiv191113049H
  Context. With an estimated diameter in the 320-350 km range, (704)
  Interamnia is the fifth largest main belt asteroid and one of the
  few bodies that fills the gap in size between the four largest bodies
  with D &gt; 400 km (Ceres, Vesta, Pallas and Hygiea) and the numerous
  smaller bodies with diameter ≤200 km. However, despite its large
  size, little is known about the shape and spin state of Interamnia
  and, therefore, about its bulk composition and past collisional
  evolution. <BR /> Aims: We aimed to test at what size and mass the
  shape of a small body departs from a nearly ellipsoidal equilibrium
  shape (as observed in the case of the four largest asteroids) to
  an irregular shape as routinely observed in the case of smaller (D
  ≤ 200 km) bodies. <BR /> Methods: We observed Interamnia as part
  of our ESO VLT/SPHERE large program (ID: 199.C-0074) at thirteen
  different epochs. In addition, several new optical lightcurves were
  recorded. These data, along with stellar occultation data from the
  literature, were fed to the All-Data Asteroid Modeling algorithm to
  reconstruct the 3D-shape model of Interamnia and to determine its spin
  state. <BR /> Results: Interamnia's volume-equivalent diameter of 332
  ± 6 km implies a bulk density of ρ = 1.98 ± 0.68 g cm<SUP>-3</SUP>,
  which suggests that Interamnia - like Ceres and Hygiea - contains a
  high fraction of water ice, consistent with the paucity of apparent
  craters. Our observations reveal a shape that can be well approximated
  by an ellipsoid, and that is compatible with a fluid hydrostatic
  equilibrium at the 2σ level. <BR /> Conclusions: The rather regular
  shape of Interamnia implies that the size and mass limit, under which
  the shapes of minor bodies with a high amount of water ice in the
  subsurface become irregular, has to be searched among smaller (D ≤
  300 km) less massive (m ≤ 3 × 10<SUP>19</SUP> kg) bodies. <P />The
  reduced images are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/633/A65">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/633/A65</A>
  <P />Based on observations made with ESO Telescopes at the La Silla
  Paranal Observatory under program 199.C-0074 (PI: Vernazza).

---------------------------------------------------------
Title: Imaging the Solar Corona From Within
Authors: Hess, P.; Howard, R.; Vourlidas, A.; Bothmer, V.; Colaninno,
   R.; DeForest, C.; Gallagher, B.; Hall, J. R.; Higginson, A.; Korendyke,
   C.; Kouloumvakos, A.; Lamy, P.; Liewer, P.; Linker, J.; Linton, M.;
   Penteado, P.; Plunkett, S.; Poirer, N.; Raouafi, N.; Rich, N.; Rochus,
   P.; Rouillard, A.; Socker, D.; Stenborg, G.; Thernisien, A.; Viall, N.
2020AAS...23514907H    Altcode:
  Parker Solar Probe (PSP), launched, in August 2018 is humanity's
  first probe of a stellar atmosphere. It will make measurements of
  the near-Sun plasma from 'within' the outer corona with gradually
  reduced perihelia from its first perihelia of 35 Rs in 2018-19 to 9.8
  Rs in 2025. Here we report the results from the imaging observations
  of the electron and dust corona, whe PSP was 35-54 Rs from the solar
  surface, taken by the Wide-field Imager for Solar Probe (WISPR). The
  spacecraft was near-corotating with the solar corona throughout the
  observing window, which is an unprecedented situation for any type of
  coronal imaging. Our initial analysis uncovers a long-hypothesized
  depletion of the primordial dust orbiting near the Sun, reveals the
  plasma structure of small-scale ejections, and provides a strict test
  for validating model predictions of the large-scale configuration of
  the coronal plasma. Thus, WISPR imaging allows the study of near-Sun
  dust dynamics as the mission progresses. The high-resolution images
  of small transients, largely unresolved from 1 AU orbits, unravel
  the sub-structures of small magnetic flux ropes and show that the
  Sun continually releases helical magnetic fields in the background
  wind. Finally, WISPR's observations of the coronal streamer evolution
  confirm the large-scale topology of the solar corona but they also
  reveal that, as recently predicted, streamers are composed of yet
  smaller sub-streamers channeling continual density fluctuations at
  all visible scales.

---------------------------------------------------------
Title: Imaging the Solar Corona from Within: First Results from the
    Parker Solar Probe Telescope
Authors: Howard, R. A.; Vourlidas, A.; Bothmer, V.; Colaninno, R. C.;
   DeForest, C.; Gallagher, B.; Hall, J. R.; Hess, P.; Higginson, A. K.;
   Korendyke, C.; Kouloumvakos, A.; Lamy, P.; Liewer, P. C.; Linker, J.;
   Linton, M.; Penteado, P. F.; Plunkett, S. P.; Poirier, N.; Raouafi,
   N.; Rich, N.; Rochus, P. L.; Rouillard, A. P.; Socker, D. G.; Stenborg,
   G.; Thernisien, A.; Viall, N. M.
2019AGUFMSH11A..04H    Altcode:
  Parker Solar Probe (PSP) launched in August 2018 is humanity's
  first probe of a stellar atmosphere. It will make measurements of
  the near-Sun plasma from 'within' the outer corona with gradually
  reduced perihelia from its first perihelia of 35 Rs in 2018-19 to 9.8
  Rs in 2025. Here we report the results from the imaging observations
  of the electron and dust corona, whe PSP was 35-54 Rs from the solar
  surface, taken by the Wide-field Imager for Solar Probe (WISPR). The
  spacecraft was near-corotating with the solar corona throughout the
  observing window, which is an unprecedented situation for any type of
  coronal imaging. Our initial analysis uncovers a long-hypothesized
  depletion of the primordial dust orbiting near the Sun, reveals the
  plasma structure of small-scale ejections, and provides a strict test
  for validating model predictions of the large-scale configuration of
  the coronal plasma. Thus, WISPR imaging allows the study of near-Sun
  dust dynamics as the mission progresses. The high-resolution images
  of small transients, largely unresolved from 1 AU orbits, unravel
  the sub-structures of small magnetic flux ropes and show that the
  Sun continually releases helical magnetic fields in the background
  wind. Finally, WISPR's observations of the coronal streamer evolution
  confirm the large-scale topology of the solar corona but they also
  reveal that, as recently predicted, streamers are composed of yet
  smaller sub-streamers channeling continual density fluctuations at
  all visible scales.

---------------------------------------------------------
Title: Polarimetric Reconstruction of Coronal Mass Ejections from
    LASCO-C2 Observations
Authors: Floyd, Olivier; Lamy, Philippe
2019SoPh..294..168F    Altcode:
  The three-dimensional morphology and direction of propagation of coronal
  mass ejections (CMEs) are essential information for identifying their
  source on the solar disk, for understanding the processes of their
  ejection and propagation in the corona, and for forecasting their
  possible impact with the Earth or any other objects in the solar
  system. The polarization of the Thomson scattering by an electron
  is known to provide information on its position with respect to
  the plane of the sky. This polarimetric technique is applied to
  reconstruct 15 CMEs on the basis of white-light polarized images
  obtained with the Large Angle Spectrometric Coronagraph (LASCO) C2,
  which have been extensively corrected for instrumental effects. It
  does provide valuable results in spite of the time delays between
  the three observations required to build the polarization maps. Most
  of these CMEs exhibit complex structures making a classification in
  terms of simple shapes such as arcade of loops or flux rope difficult
  or even questionable. Three of these CMEs benefited from multiple
  observations allowing us to follow their three-dimensional development
  as they propagated outward. All CMEs are tracked back to the solar
  surface and in several instances, active regions are identified as
  the probable sources. Finally, the projected speeds and masses derived
  from white-light unpolarized observations have been corrected for the
  projection angle to produce unbiased values.

---------------------------------------------------------
Title: The Solar Orbiter Heliospheric Imager (SoloHI) for the Solar
Orbiter Mission: Science and Instrument Status
Authors: Vourlidas, A.; Howard, R. A.; Colaninno, R. C.; Korendyke,
   C.; Thernisien, A.; Linton, M.; Tun Beltran, S.; Liewer, P. C.; Velli,
   M.; Linker, J.; Bothmer, V.; Rochus, P. L.; Lamy, P. L.
2019AGUFMSH24A..08V    Altcode:
  The SoloHI instrument has completed its development effort and has been
  integrated onto the Solar Orbiter spacecraft. The mission, scheduled
  for launch in February 2020, will undergo gravity assist maneuvers
  around Venus to change both the perihelion distance as well as the
  plane of the orbit to ultimately achieve a minimum perihelion of 0.28
  AU and an orbital inclination of about 35° relative to the ecliptic
  plane. The remote sensing instruments will operate for three 10-day
  periods out of the nominal 6-month orbit. SoloHI detects sunlight
  scattered by free electrons in the corona and solar wind from 5° to
  45° elongation in visible wavelengths, providing linkage between solar
  and solar wind observations. The science investigation focuses mainly on
  the solar wind, including streamers, small-scale intensity and density
  fluctuations, jets, and Coronal Mass Ejections (CMEs). SoloHI is very
  similar to the HI-1 instrument on STEREO/SECCHI but with double the FOV
  of HI-1. In this paper, we present our preparations for the mission
  including the instrument status, our science planning strategy, our
  observing plans for cruise phase, calibrations, early science and our
  low-latency and science data products <P />This work has been supported
  by NASA.

---------------------------------------------------------
Title: Near-Sun observations of an F-corona decrease and K-corona
    fine structure
Authors: Howard, R. A.; Vourlidas, A.; Bothmer, V.; Colaninno, R. C.;
   DeForest, C. E.; Gallagher, B.; Hall, J. R.; Hess, P.; Higginson,
   A. K.; Korendyke, C. M.; Kouloumvakos, A.; Lamy, P. L.; Liewer, P. C.;
   Linker, J.; Linton, M.; Penteado, P.; Plunkett, S. P.; Poirier, N.;
   Raouafi, N. E.; Rich, N.; Rochus, P.; Rouillard, A. P.; Socker, D. G.;
   Stenborg, G.; Thernisien, A. F.; Viall, N. M.
2019Natur.576..232H    Altcode:
  Remote observations of the solar photospheric light scattered by
  electrons (the K-corona) and dust (the F-corona or zodiacal light)
  have been made from the ground during eclipses<SUP>1</SUP> and from
  space at distances as small as 0.3 astronomical units<SUP>2-5</SUP> to
  the Sun. Previous observations<SUP>6-8</SUP> of dust scattering have
  not confirmed the existence of the theoretically predicted dust-free
  zone near the Sun<SUP>9-11</SUP>. The transient nature of the corona
  has been well characterized for large events, but questions still
  remain (for example, about the initiation of the corona<SUP>12</SUP>
  and the production of solar energetic particles<SUP>13</SUP>) and
  for small events even its structure is uncertain<SUP>14</SUP>. Here
  we report imaging of the solar corona<SUP>15</SUP> during the first
  two perihelion passes (0.16-0.25 astronomical units) of the Parker
  Solar Probe spacecraft<SUP>13</SUP>, each lasting ten days. The view
  from these distances is qualitatively similar to the historical views
  from ground and space, but there are some notable differences. At
  short elongations, we observe a decrease in the intensity of the
  F-coronal intensity, which is suggestive of the long-sought dust
  free zone<SUP>9-11</SUP>. We also resolve the fine-scale plasma
  structure of very small eruptions, which are frequently ejected from
  the Sun. These take two forms: the frequently observed magnetic flux
  ropes<SUP>12,16</SUP> and the predicted, but not yet observed, magnetic
  islands<SUP>17,18</SUP> arising from the tearing-mode instability in
  the current sheet. Our observations of the coronal streamer evolution
  confirm the large-scale topology of the solar corona, but also reveal
  that, as recently predicted<SUP>19</SUP>, streamers are composed of
  yet smaller substreamers channelling continual density fluctuations
  at all visible scales.

---------------------------------------------------------
Title: Spitzer Space Telescope observations of bilobate comet
    8P/Tuttle
Authors: Groussin, O.; Lamy, P. L.; Kelley, M. S. P.; Toth, I.; Jorda,
   L.; Fernández, Y. R.; Weaver, H. A.
2019A&A...632A.104G    Altcode: 2019arXiv191104897G
  Context. Comet 8P/Tuttle is a nearly isotropic comet whose physical
  properties are poorly known and might be different from those of
  ecliptic comets owing to their different origin. Two independent
  observations have shown that 8P/Tuttle has a bilobate nucleus. <BR />
  Aims: Our goal is to determine the physical properties of the nucleus
  (size, shape, thermal inertia, and albedo) and coma (water and dust) of
  8P/Tuttle. <BR /> Methods: We observed the inner coma of 8P/Tuttle with
  the infrared spectrograph and the infrared camera of the Spitzer Space
  Telescope. We obtained one spectrum (5-40 μm) on 2 November 2007 and a
  set of 19 images at 24 μm on 22-23 June 2008 sampling the rotational
  period of the nucleus. The data were interpreted using thermal models
  for the nucleus and the dust coma, and we considered two possible shape
  models of the nucleus derived from Hubble Space Telescope visible and
  Arecibo radar observations. <BR /> Results: We favor a model for the
  nucleus shape that is composed of two contact spheres with respective
  radii of 2.7 ± 0.1 km and 1.1 ± 0.1 km and a pole orientation with RA
  = 285 ± 12° and Dec = +20 ± 5°. The thermal inertia of the nucleus
  lies in the range 0-100 J K<SUP>-1</SUP> m<SUP>-2</SUP> s<SUP>-1/2</SUP>
  and the R-band geometric albedo is 0.042 ± 0.008. The water production
  rate amounts to 1.1 ± 0.2 × 10<SUP>28</SUP> molecules s<SUP>-1</SUP>
  at 1.6 AU from the Sun pre-perihelion, which corresponds to an active
  fraction of ≈9%. At the same distance, the ɛfρ quantity amounts to
  310 ± 34 cm, and it reaches 325 ± 36 cm at 2.2 AU post-perihelion. The
  dust grain temperature is estimated to be 258 ± 10 K, which is 37
  K higher than the thermal equilibrium temperature at 1.6 AU. This
  indicates that the dust grains that contribute to the thermal infrared
  flux have a typical size of ≈10 μm. The dust spectrum exhibits
  broad emission around 10 μm (1.5σ confidence level) and 18 μm
  (5σ confidence level) that we attribute to amorphous pyroxene.

---------------------------------------------------------
Title: Validation of the Alfvén Wave Solar Atmosphere Model (AWSoM)
    with Observations from the Low Corona to 1 au
Authors: Sachdeva, Nishtha; van der Holst, Bart; Manchester, Ward B.;
   Tóth, Gabor; Chen, Yuxi; Lloveras, Diego G.; Vásquez, Alberto M.;
   Lamy, Philippe; Wojak, Julien; Jackson, Bernard V.; Yu, Hsiu-Shan;
   Henney, Carl J.
2019ApJ...887...83S    Altcode: 2019arXiv191008110S
  We perform a validation study of the latest version of the Alfvén
  Wave Solar atmosphere Model (AWSoM) within the Space Weather Modeling
  Framework. To do so, we compare the simulation results of the model
  with a comprehensive suite of observations for Carrington rotations
  representative of the solar minimum conditions extending from the
  solar corona to the heliosphere up to the Earth. In the low corona
  (r &lt; 1.25 {\text{}}{R}<SUB>⊙ </SUB>), we compare with EUV
  images from both Solar-Terrestrial Relations Observatory-A/EUVI
  and Solar Dynamics Observatory/Atmospheric Imaging Assembly and to
  three-dimensional (3D) tomographic reconstructions of the electron
  temperature and density based on these same data. We also compare the
  model to tomographic reconstructions of the electron density from
  Solar and Heliospheric Observatory/Large Angle and Spectrometric
  Coronagraph observations (2.55 &lt; r &lt; 6.0{\text{}}{R}<SUB>⊙
  </SUB>). In the heliosphere, we compare model predictions of solar wind
  speed with velocity reconstructions from InterPlanetary Scintillation
  observations. For comparison with observations near the Earth, we use
  OMNI data. Our results show that the improved AWSoM model performs
  well in quantitative agreement with the observations between the inner
  corona and 1 au. The model now reproduces the fast solar wind speed
  in the polar regions. Near the Earth, our model shows good agreement
  with observations of solar wind velocity, proton temperature, and
  density. AWSoM offers an extensive application to study the solar
  corona and larger heliosphere in concert with current and future solar
  missions as well as being well suited for space weather predictions.

---------------------------------------------------------
Title: The Rocky-Like Behavior of Cometary Landslides on
    67P/Churyumov-Gerasimenko
Authors: Lucchetti, Alice; Penasa, Luca; Pajola, Maurizio; Massironi,
   Matteo; Brunetti, Maria Teresa; Cremonese, Gabriele; Oklay, Nilda;
   Vincent, Jean-Baptiste; Mottola, Stefano; Fornasier, Sonia; Sierks,
   Holger; Naletto, Giampiero; Lamy, Philippe L.; Rodrigo, Rafael;
   Koschny, Detlef; Davidsson, Bjorn; Barbieri, Cesare; Barucci,
   Maria Antonietta; Bertaux, Jean-Loup; Bertini, Ivano; Bodewits,
   Dennis; Cambianica, Pamela; Da Deppo, Vania; Debei, Stefano; De
   Cecco, Mariolino; Deller, Jacob; Ferrari, Sabrina; Ferri, Francesca;
   Franceschi, Marco; Fulle, Marco; Gutiérrez, Pedro; Güttler, Carsten;
   Ip, Wing-H.; Keller, Uwe; Lara, Luisa; Lazzarin, Monica; Moreno,
   Jose Lopez; Marzari, Francesco; Tubiana, Cecilia
2019GeoRL..4614336L    Altcode:
  Landslides have been identified on several solar system bodies,
  and different mechanisms have been proposed to explain their runout
  length. We analyze images from the Rosetta mission and report the global
  characterization of such features on comet 67P/Churyumov-Gerasimenko's
  surface. By assuming the height to runout length as an approximation for
  the friction coefficient of landslide material, we find that on comet
  67P, this ratio falls between 0.50 and 0.97. Such unexpected high values
  reveal a rocky-type mechanical behavior that is much more akin to Earth
  dry landslides than to icy satellites' mass movements. This behavior
  indicates that 67P and likely comets in general are characterized by
  consolidated materials possibly rejecting the idea that they are fluffy
  aggregates. The variability of the runout length among 67P landslides
  can be attributed to the different volatile content located in the
  top few meters of the cometary crust, which can drive the mass movement.

---------------------------------------------------------
Title: Validating the Alfven Wave Solar Atmosphere (AWSoM) Model
    from the Low Corona to 1 AU
Authors: Sachdeva, N.; van der Holst, B.; Manchester, W.; Toth, G.;
   Lloveras, D. G.; Vásquez, A. M.; Lamy, P.; Jackson, B. V.; Henney,
   C. J.
2019AGUFMSH51A..04S    Altcode:
  The coronal/solar wind model, the Alfven Wave Solar atmosphere Model
  (AWSoM) a component within the Space Weather Modeling Framework (SWMF)
  follows a self-consistent physics-based global description of coronal
  heating and solar wind acceleration. AWSoM includes a description
  of low-frequency forward and counter-propagating Alfven waves that
  non-linearly interact resulting in a turbulent cascade and dissipative
  heating. In addition, there are separate temperatures for electrons and
  protons with collisional and collisionless heat conduction applied only
  to electrons and radiative losses based on the Chianti model. AWSoM
  extends from the base of the transition region where the strong
  density gradient necessitates self-consistent treatment of Alfven wave
  reflection and balanced turbulence. It includes a stochastic heating
  model as well as a description of proton parallel and perpendicular
  temperatures and kinetic instabilities based on temperature anisotropy
  and plasma beta.To validate AWSoM, we model Carrington rotations
  representative of solar minimum conditions and compare the simulation
  results with a comprehensive suite of observations. In the low corona
  (r &lt; 1.25 Rs), we compare with EUV images from both STEREOA/EUVI
  and SDO/AIA and to three-dimensional tomographic reconstructions of
  the electron temperature and density based on these same data. We
  also compare the model to tomographic reconstructions of the electron
  density from SOHO/LASCO observations (2.55 &lt; r &lt; 6 Rs). In
  the heliosphere, we compare model predictions of solar wind speed
  with velocity reconstructions from Interplanetary Scintillation
  observations. For comparison with observations near the Earth, we
  use OMNI data. Our results show that the AWSoM model performs well
  in quantitative agreement with the observations between the inner
  corona and 1 AU. In the lower corona, the model and the tomographic
  reconstructions agree within 20%-30% on average. The model also
  reproduces the fast solar wind speed in the polar regions. Near the
  Earth, our model shows good agreement with observations of solar wind
  velocity, electron temperature and density. The AWSoM model provides
  a comprehensive tool to study the solar corona and larger heliosphere
  with current and future solar missions as well as being well suited
  for space weather predictions.

---------------------------------------------------------
Title: VizieR Online Data Catalog: (704) Interamnia images (Hanus+,
    2020)
Authors: Hanus, J.; Vernazza, P.; Viikinkoski, M.; Ferrais, M.;
   Rambaux, N.; Podlewska-Gaca, E.; Drouard, A.; Jorda, L.; Jehin, E.;
   Carry, B.; Marsset, M.; Marchis, F.; Warner, B.; Behrend, R.; Asenjo,
   V.; Berger, N.; Bronikowska, M.; Brothers, T.; Charbonnel, S.; Colazo,
   C.; Coliac, J. -F.; Duard, R.; Jones, A.; Leroy, A.; Marciniak, A.;
   Melia, R.; Molina, D.; Nadolny, J.; Person, M.; Pejcha, O.; Riemis,
   H.; Shappee, B.; Sobkowiak, K.; Sold'An, F.; Suys, D.; Szakats, R.;
   Vantomme, J.; Birlan, M.; Berthier, J.; Bartczak, P.; Dumas, C.;
   Dudzin'ski, G.; Durech, J.; Castillo-Rogez, J.; Cipriani, F.; Fetick,
   R.; Fusco, T.; Grice, J.; Kaasalainen, M.; Kryszczynska, A.; Lamy,
   P.; Michalowski, T.; Michel, P.; Santana-Ros, T.; Tanga, P.; Vachier,
   F.; Vigan, A.; Witasse, O.; Yang, B.
2019yCat..36330065H    Altcode:
  Deconvolved disk-resolved images of asteroid (704) Interamnia from
  VLT/SPHERE/Zimpol instrument listed in Table A1. <P />(2 data files).

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Title: Validation of MHD Model Predictions of the Corona with LASCO-C2
    Polarized Brightness Images
Authors: Lamy, Philippe; Floyd, Olivier; Mikić, Zoran; Riley, Pete
2019SoPh..294..162L    Altcode:
  Progress in our understanding of the solar corona requires that the
  results of advanced magnetohydrodynamic models driven by measured
  magnetic fields, and particularly the underlying heating models, be
  thoroughly compared with coronal observations. The comparison has so far
  mainly concerned the global morphology of the corona, synthetic images
  calculated from the models being compared with observed images. We go
  one step further by performing detailed quantitative comparisons between
  the calculated polarized radiance p B using the three-dimensional
  electron density produced by MHD models and well calibrated polarized
  images obtained by the Large Angle Spectrometric Coronagraph LASCO-C2
  coronagraph complemented by ground-based images when available from
  the Mauna Loa Solar Observatory Mark IV and K-Cor instruments to extend
  the comparison to the inner coronal region 1.0 - 2.5 <SUB>R⊙</SUB>,
  which is inaccessible to C2. We take advantage of the high-resolution
  and high-quality MHD predictions performed for several solar eclipses
  (1 August 2008, 11 July 2010, 13 November 2012, and 21 August 2017) and
  for the first perihelion passage of the Parker Solar Probe (5 November
  2018) using two different three-dimensional MHD models relying on either
  a thermodynamic or a wave-turbulence-driven methodologies to heat the
  corona. Both models are generally able to match the observed structure
  and photometry of the corona albeit with various degrees of fidelity for
  which there is no obvious explanation. However, two limitations emerge,
  the complexity of coronae of the maximum type and the time lapse between
  the completion of the magnetograph measurements and the prediction.

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Title: Diurnal variation of dust and gas production in comet
    67P/Churyumov-Gerasimenko at the inbound equinox as seen by OSIRIS
    and VIRTIS-M on board Rosetta
Authors: Tubiana, C.; Rinaldi, G.; Güttler, C.; Snodgrass, C.; Shi,
   X.; Hu, X.; Marschall, R.; Fulle, M.; Bockelée-Morvan, D.; Naletto,
   G.; Capaccioni, F.; Sierks, H.; Arnold, G.; Barucci, M. A.; Bertaux,
   J. -L.; Bertini, I.; Bodewits, D.; Capria, M. T.; Ciarniello, M.;
   Cremonese, G.; Crovisier, J.; Da Deppo, V.; Debei, S.; De Cecco, M.;
   Deller, J.; De Sanctis, M. C.; Davidsson, B.; Doose, L.; Erard, S.;
   Filacchione, G.; Fink, U.; Formisano, M.; Fornasier, S.; Gutiérrez,
   P. J.; Ip, W. -H.; Ivanovski, S.; Kappel, D.; Keller, H. U.;
   Kolokolova, L.; Koschny, D.; Krueger, H.; La Forgia, F.; Lamy, P. L.;
   Lara, L. M.; Lazzarin, M.; Levasseur-Regourd, A. C.; Lin, Z. -Y.;
   Longobardo, A.; López-Moreno, J. J.; Marzari, F.; Migliorini, A.;
   Mottola, S.; Rodrigo, R.; Taylor, F.; Toth, I.; Zakharov, V.
2019A&A...630A..23T    Altcode: 2019arXiv190503022T
  Context. On 27 April 2015, when comet 67P/Churyumov-Gerasimenko was
  at 1.76 au from the Sun and moving toward perihelion, the OSIRIS and
  VIRTIS-M instruments on board the Rosetta spacecraft simultaneously
  observed the evolving dust and gas coma during a complete rotation of
  the comet. <BR /> Aims: We aim to characterize the spatial distribution
  of dust, H<SUB>2</SUB>O, and CO<SUB>2</SUB> gas in the inner coma. To
  do this, we performed a quantitative analysis of the release of dust
  and gas and compared the observed H<SUB>2</SUB>O production rate with
  the rate we calculated using a thermophysical model. <BR /> Methods:
  For this study we selected OSIRIS WAC images at 612 nm (dust) and
  VIRTIS-M image cubes at 612 nm, 2700 nm (H<SUB>2</SUB>O emission
  band), and 4200 nm (CO<SUB>2</SUB> emission band). We measured the
  average signal in a circular annulus to study the spatial variation
  around the comet, and in a sector of the annulus to study temporal
  variation in the sunward direction with comet rotation, both at a fixed
  distance of 3.1 km from the comet center. <BR /> Results: The spatial
  correlation between dust and water, both coming from the sunlit side
  of the comet, shows that water is the main driver of dust activity in
  this time period. The spatial distribution of CO<SUB>2</SUB> is not
  correlated with water and dust. There is no strong temporal correlation
  between the dust brightness and water production rate as the comet
  rotates. The dust brightness shows a peak at 0° subsolar longitude,
  which is not pronounced in the water production. At the same epoch,
  there is also a maximum in CO<SUB>2</SUB> production. An excess of
  measured water production with respect to the value calculated using
  a simple thermophysical model is observed when the head lobe and
  regions of the southern hemisphere with strong seasonal variations
  are illuminated (subsolar longitude 270°-50°). A drastic decrease in
  dust production when the water production (both measured and from the
  model) displays a maximum occurs when typical northern consolidated
  regions are illuminated and the southern hemisphere regions with
  strong seasonal variations are instead in shadow (subsolar longitude
  50°-90°). Possible explanations of these observations are presented
  and discussed.

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Title: Rosetta/OSIRIS observations of the 67P nucleus during the
April 2016 flyby: high-resolution spectrophotometry
Authors: Feller, C.; Fornasier, S.; Ferrari, S.; Hasselmann,
   P. H.; Barucci, A.; Massironi, M.; Deshapriya, J. D. P.; Sierks,
   H.; Naletto, G.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Davidsson,
   B. J. R.; Bertaux, J. -L.; Bertini, I.; Bodewits, D.; Cremonese, G.;
   Da Deppo, V.; Debei, S.; De Cecco, M.; Fulle, M.; Gutiérrez, P. J.;
   Güttler, C.; Ip, W. -H.; Keller, H. U.; Lara, L. M.; Lazzarin, M.;
   López-Moreno, J. J.; Marzari, F.; Shi, X.; Tubiana, C.; Gaskell, B.;
   La Forgia, F.; Lucchetti, A.; Mottola, S.; Pajola, M.; Preusker, F.;
   Scholten, F.
2019A&A...630A...9F    Altcode: 2018arXiv181209415F
  Context. From August 2014 to September 2016, the Rosetta spacecraft
  followed comet 67P/Churyumov-Gerasimenko along its orbit. After the
  comet passed perihelion, Rosetta performed a flyby manoeuvre over the
  Imhotep-Khepry transition in April 2016. The OSIRIS/Narrow-Angle-Camera
  (NAC) acquired 112 observations with mainly three broadband filters
  (centered at 480, 649, and 743 nm) at a resolution of up to 0.53
  m/px and for phase angles between 0.095° and 62°. <BR /> Aims:
  We have investigated the morphological and spectrophotometrical
  properties of this area using the OSIRIS/NAC high-resolution
  observations. <BR /> Methods: We assembled the observations into
  coregistered color cubes. Using a 3D shape model, we produced the
  illumination conditions and georeference for each observation. We
  mapped the observations of the transition to investigate its
  geomorphology. Observations were photometrically corrected using the
  Lommel-Seeliger disk law. Spectrophotometric analyses were performed
  on the coregistered color cubes. These data were used to estimate the
  local phase reddening. <BR /> Results: The Imhotep-Khepry transition
  hosts numerous and varied types of terrains and features. We observe
  an association between a feature's nature, its reflectance, and its
  spectral slopes. Fine material deposits exhibit an average reflectance
  and spectral slope, while terrains with diamictons, consolidated
  material, degraded outcrops, or features such as somber boulders present
  a lower-than-average reflectance and higher-than-average spectral
  slope. Bright surfaces present here a spectral behavior consistent
  with terrains enriched in water-ice. We find a phase-reddening slope
  of 0.064 ± 0.001%/100 nm/° at 2.7 au outbound, similar to the one
  obtained at 2.3 au inbound during the February 2015 flyby. <BR />
  Conclusions: Identified as the source region of multiple jets and a
  host of water-ice material, the Imhotep-Khepry transition appeared in
  April 2016, close to the frost line, to further harbor several potential
  locations with exposed water-ice material among its numerous different
  morphological terrain units.

---------------------------------------------------------
Title: Surface evolution of the Anhur region on comet
    67P/Churyumov-Gerasimenko from high-resolution OSIRIS images
Authors: Fornasier, S.; Feller, C.; Hasselmann, P. H.; Barucci,
   M. A.; Sunshine, J.; Vincent, J. -B.; Shi, X.; Sierks, H.; Naletto,
   G.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Davidsson, B.; Bertaux,
   J. -L.; Bertini, I.; Bodewits, D.; Cremonese, G.; Da Deppo, V.; Debei,
   S.; De Cecco, M.; Deller, J.; Ferrari, S.; Fulle, M.; Gutierrez,
   P. J.; Güttler, C.; Ip, W. -H.; Jorda, L.; Keller, H. U.; Lara,
   M. L.; Lazzarin, M.; Lopez Moreno, J. J.; Lucchetti, A.; Marzari,
   F.; Mottola, S.; Pajola, M.; Toth, I.; Tubiana, C.
2019A&A...630A..13F    Altcode: 2019arXiv190309017F
  Context. The southern hemisphere of comet 67P/Churyumov-Gerasimenko
  (67P) became observable by the Rosetta mission in March 2015,
  a few months before cometary southern vernal equinox. The Anhur
  region in the southern part of the comet's larger lobe was found
  to be highly eroded, enriched in volatiles, and highly active. <BR
  /> Aims: We analyze high-resolution images of the Anhur region
  pre- and post-perihelion acquired by the OSIRIS imaging system on
  board the Rosetta mission. The Narrow Angle Camera is particularly
  useful for studying the evolution in Anhur in terms of morphological
  changes and color variations. <BR /> Methods: Radiance factor images
  processed by the OSIRIS pipeline were coregistered, reprojected onto
  the 3D shape model of the comet, and corrected for the illumination
  conditions. <BR /> Results: We find a number of morphological changes
  in the Anhur region that are related to formation of new scarps;
  removal of dust coatings; localized resurfacing in some areas,
  including boulders displacements; and vanishing structures, which
  implies localized mass loss that we estimate to be higher than 50
  million kg. The strongest changes took place in and nearby the Anhur
  canyon-like structure, where significant dust cover was removed,
  an entire structure vanished, and many boulders were rearranged. All
  such changes are potentially associated with one of the most intense
  outbursts registered by Rosetta during its observations, which occurred
  one day before perihelion passage. Moreover, in the niche at the foot
  of a new observed scarp, we also see evidence of water ice exposure
  that persisted for at least six months. The abundance of water ice,
  evaluated from a linear mixing model, is relatively high (&gt;20%). Our
  results confirm that the Anhur region is volatile-rich and probably is
  the area on 67P with the most pristine exposures near perihelion. <P
  />The movies associated to Figs. 2, 7, 8, and 10 are available at <A
  href="https://www.aanda.org/10.1051/0004-6361/201834824/olm">https://www.aanda.org</A>

---------------------------------------------------------
Title: Linking surface morphology, composition, and activity on the
    nucleus of 67P/Churyumov-Gerasimenko
Authors: Fornasier, S.; Hoang, V. H.; Hasselmann, P. H.; Feller,
   C.; Barucci, M. A.; Deshapriya, J. D. P.; Sierks, H.; Naletto, G.;
   Lamy, P. L.; Rodrigo, R.; Koschny, D.; Davidsson, B.; Agarwal, J.;
   Barbieri, C.; Bertaux, J. -L.; Bertini, I.; Bodewits, D.; Cremonese,
   G.; Da Deppo, V.; Debei, S.; De Cecco, M.; Deller, J.; Ferrari, S.;
   Fulle, M.; Gutierrez, P. J.; Güttler, C.; Ip, W. -H.; Keller, H. U.;
   Küppers, M.; La Forgia, F.; Lara, M. L.; Lazzarin, M.; Lin, Z. -Y.;
   Lopez Moreno, J. J.; Marzari, F.; Mottola, S.; Pajola, M.; Shi, X.;
   Toth, I.; Tubiana, C.
2019A&A...630A...7F    Altcode: 2018arXiv180903997F
  <BR /> Aims: The Rosetta space probe accompanied comet
  67P/Churyumov-Gerasimenko for more than two years, obtaining an
  unprecedented amount of unique data of the comet nucleus and inner
  coma. This has enabled us to study its activity almost continuously
  from 4 au inbound to 3.6 au outbound, including the perihelion passage
  at 1.24 au. This work focuses identifying the source regions of faint
  jets and outbursts and on studying the spectrophotometric properties of
  some outbursts. We use observations acquired with the OSIRIS/NAC camera
  during July-October 2015, that is, close to perihelion. <BR /> Methods:
  We analyzed more than 2000 images from NAC color sequences acquired
  with 7-11 filters covering the 250-1000 nm wavelength range. The
  OSIRIS images were processed with the OSIRIS standard pipeline up to
  level 3, that is, converted in radiance factor, then corrected for
  the illumination conditions. For each color sequence, color cubes
  were produced by stacking registered and illumination-corrected
  images. <BR /> Results: More than 200 jets of different intensities
  were identified directly on the nucleus. Some of the more intense
  outbursts appear spectrally bluer than the comet dark terrain in the
  visible-to-near-infrared region. We attribute this spectral behavior
  to icy grains mixed with the ejected dust. Some of the jets have an
  extremely short lifetime. They appear on the cometary surface during
  the color sequence observations, and vanish in less than some few
  minutes after reaching their peak. We also report a resolved dust plume
  observed in May 2016 at a resolution of 55 cm pixel<SUP>-1</SUP>, which
  allowed us to estimate an optical depth of ~0.65 and an ejected mass of
  ~2200 kg, assuming a grain bulk density of ~800 kg m<SUP>-3</SUP>. We
  present the results on the location, duration, and colors of active
  sources on the nucleus of 67P from the medium-resolution (i.e., 6-10
  m pixel<SUP>-1</SUP>) images acquired close to perihelion passage. The
  observed jets are mainly located close to boundaries between different
  morphological regions. Some of these active areas were observed and
  investigated at higher resolution (up to a few decimeter per pixel)
  during the last months of operations of the Rosetta mission. <BR />
  Conclusions: These observations allow us to investigate the link between
  morphology, composition, and activity of cometary nuclei. Jets depart
  not only from cliffs, but also from smooth and dust-covered areas,
  from fractures, pits, or cavities that cast shadows and favor the
  recondensation of volatiles. This study shows that faint jets or
  outbursts continuously contribute to the cometary activity close to
  perihelion passage, and that these events are triggered byillumination
  conditions. Faint jets or outbursts are not associated with a particular
  terrain type or morphology.

---------------------------------------------------------
Title: Seasonal variations in source regions of the dust jets on
    comet 67P/Churyumov-Gerasimenko
Authors: Lai, I. -L.; Ip, W. -H.; Lee, J. -C.; Lin, Z. -Y.; Vincent,
   J. -B.; Oklay, N.; Sierks, H.; Barbieri, C.; Lamy, P.; Rodrigo, R.;
   Koschny, D.; Rickman, H.; Keller, H. U.; Agarwal, J.; Barucci, M. A.;
   Bertaux, J. -L.; Bertini, I.; Bodewits, D.; Boudreault, S.; Cremonese,
   G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.; Deller, J.;
   Fornasier, S.; Fulle, M.; Groussin, O.; Gutiérrez, P. J.; Güttler,
   C.; Hofmann, M.; Hviid, S. F.; Jorda, L.; Knollenberg, J.; Kovacs,
   G.; Kramm, J. -R.; Kührt, E.; Küppers, M.; Lara, L. M.; Lazzarin,
   M.; López-Moreno, J. J.; Marzari, F.; Naletto, G.; Shi, X.; Tubiana,
   C.; Thomas, N.
2019A&A...630A..17L    Altcode:
  <BR /> Aims: We investigate the surface distribution of the source
  regions of dust jets on comet 67P/Churyumov-Gerasimenko as a
  function of time. <BR /> Methods: The dust jet source regions were
  traced by the comprehensive imaging data set provided by the OSIRIS
  scientific camera. <BR /> Results: We show in detail how the projected
  footpoints of the dust jets and hence the outgassing zone would move
  in consonance with the sunlit belt. Furthermore, a number of source
  regions characterized by repeated jet activity might be the result of
  local topographical variations or compositional heterogeneities. <BR />
  Conclusions: The spatial and temporal variations in source regions of
  the dust jets are influenced significantly by the seasonal effect. The
  strong dependence on the solar zenith angle and local time could be
  related to the gas sublimation process driven by solar insolation on
  a surface layer of low thermal inertia.

---------------------------------------------------------
Title: Pronounced morphological changes in a southern active zone
    on comet 67P/Churyumov-Gerasimenko
Authors: Hasselmann, P. H.; Barucci, M. A.; Fornasier, S.;
   Bockelée-Morvan, D.; Deshapriya, J. D. P.; Feller, C.; Sunshine,
   J.; Hoang, V.; Sierks, H.; Naletto, G.; Lamy, P. L.; Rodrigo, R.;
   Koschny, D.; Davidsson, B.; Bertaux, J. -L.; Bertini, I.; Bodewits,
   D.; Cremonese, G.; Da Deppo, V.; Debei, S.; Fulle, M.; Gutierrez,
   P. J.; Güttler, C.; Deller, J.; Ip, W. -H.; Keller, H. U.; Lara,
   L. M.; De Cecco, M.; Lazzarin, M.; López-Moreno, J. J. L.; Marzari,
   F.; Shi, X.; Tubiana, C.
2019A&A...630A...8H    Altcode:
  A smooth deposit in the southern Khonsu region has been seen in
  ESA/Rosetta observations as active during the second half of 2015,
  when the southern summer coincided with the perihelion passage of
  67P/Churyumov-Gerasimenko (67P). Image color sequences acquired by the
  OSIRIS instrument in the period of January 2015 to July 2016, pre-
  and post-perihelion, show the occurrence of several small transient
  events as well as three massive outbursts ( 10 to 1500 tons). High
  spatial resolution images taken one year and a half apart allowed
  us to track a variety of sources: the formation of cavities that are
  1.3-14 m deep, ice-enriched patches, scarp retraction, and a second
  50 m-wide boulder. We then estimated their masses and the dust mass of
  their corresponding plumes and outbursts. In particular, the deformation
  left by that boulder and its lack of talus may provide evidence for the
  lifting and subsequent falling back to the surface of large blocks. We
  calculate that a minimum vapor production rate of 1.4 × 10<SUP>24</SUP>
  m<SUP>-2</SUP> s<SUP>-1</SUP> is required to lift such an object. The
  comparison of the masses that are lost in the new cavities to the
  dust mass of outbursts gives indirect evidence of highly volatile
  ice pockets underneath. The spectrophotometric analysis and boulder
  counting also provides evidence for cavities that formed only 30 m
  apart with different spectral slopes, two long-standing ice patches,
  and local variations in the boulder-size frequency distribution. All
  this points to sub-surface ice pockets with different degrees of
  depth. Finally, the total mass of the morphological changes compared
  to most recent calculations of the total released mass by activity on
  67P is estimated to be between 1.5 and 4.2%. This means that as many
  as about 25 similar active zones across the nucleus would be enough
  to sustain the entire cometary activity.

---------------------------------------------------------
Title: Quantitative analysis of isolated boulder fields on comet
    67P/Churyumov-Gerasimenko
Authors: Cambianica, P.; Cremonese, G.; Naletto, G.; Lucchetti, A.;
   Pajola, M.; Penasa, L.; Simioni, E.; Massironi, M.; Ferrari, S.;
   Bodewits, D.; La Forgia, F.; Sierks, H.; Lamy, P. L.; Rodrigo, R.;
   Koschny, D.; Davidsson, B.; Barucci, M. A.; Bertaux, J. -L.; Bertini,
   I.; Da Deppo, V.; Debei, S.; De Cecco, M.; Deller, J.; Fornasier,
   S.; Fulle, M.; Gutiérrez, P. J.; Güttler, C.; Ip, W. -H.; Keller,
   H. U.; Lara, L. M.; Lazzarin, M.; Lin, Z. -Y.; López-Moreno, J. J.;
   Marzari, F.; Mottola, S.; Shi, X.; Scholten, F.; Toth, I.; Tubiana,
   C.; Vincent, J. -B.
2019A&A...630A..15C    Altcode:
  <BR /> Aims: We provide a detailed quantitative analysis of
  isolated boulder fields situated in three different regions of comet
  67P/Churyumov-Gerasimenko: Imhotep, Hapi, and Hatmehit. This is done
  to supply a useful method for analyzing the morphology of the boulders
  and to characterize the regions themselves. <BR /> Methods: We used
  OSIRIS Narrow Angle Camera images with a spatial scale smaller than
  2 m px<SUP>-1</SUP> and analyzed the size-frequency distribution and
  the cumulative fractional area per boulder population. In addition,
  we correlated shape parameters, such as circularity and solidity,
  with both the spatial and the size-frequency distribution of the
  three populations. <BR /> Results: We identified 11 811 boulders in
  the Imhotep, Hapi, and Hatmehit regions. We found that the Hatmehit
  and Imhotep areas show power indices in the range of -2.3/-2.7. These
  values could represent a transition between gravitational events
  caused by thermal weathering and sublimation, and material formed
  during collapses that has undergone sublimation. The Hapi area is
  characterized by a lower power index (-1.2/-1.7), suggesting that those
  boulders have a different origin. They can be the result of material
  formed during gravitational events and collapses that has undergone
  continuous fragmentation. We calculated the cumulative fractional area
  (CFA) in order to investigate how the area is covered by boulders as a
  function of their sizes. The Hatmehit and Imhotep regions show a CFA
  that is well fit by a power law. In contrast, the Hapi area does not
  show the same trend. We analyzed the fractal distributions, finding that
  the populations seem to be fractal at all dimensions, except for the
  Hapi distribution, which shows a possible fractal behavior for small
  dimensions only. Finally, the average values of the shape parameters
  reveal solid and roundish boulders in all populations we studied.

---------------------------------------------------------
Title: Phase-curve analysis of comet 67P/Churyumov-Gerasimenko at
    small phase angles
Authors: Masoumzadeh, N.; Kolokolova, L.; Tubiana, C.; El-Maarry,
   M. R.; Mottola, S.; Güttler, C.; Snodgrass, C.; Sierks, H.; Naletto,
   G.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Davidsson, B.; Barucci,
   M. A.; Bertaux, J. -L.; Bertini, I.; Bodewits, D.; Cremonese, G.;
   Da Deppo, V.; Debei, S.; De Cecco, M.; Deller, J.; Fornasier, S.;
   Fulle, M.; Gutiérrez, P. J.; Hasselmann, P. H.; Ip, W. -H.; Keller,
   H. U.; Lara, L. M.; Lazzarin, M.; López-Moreno, J. J.; Marzari, F.;
   Shi, X.; Toth, I.
2019A&A...630A..11M    Altcode:
  <BR /> Aims: The Rosetta-OSIRIS images acquired at small phase angles
  in three wavelengths during the fly-by of the spacecraft on 9-10
  April 2016 provided a unique opportunity to study the opposition
  effect on the surface of comet 67P/Churyumov-Gerasimenko (67P). Our
  goal is to study phase curves of the nucleus at small phase angles
  for a variety of surface structures to show the differences in their
  opposition effect and to determine which surface properties cause the
  differences. <BR /> Methods: We used OSIRIS NAC images that cover the
  Ash-Khepry-Imhotep region to extract the phase curve, that is, the
  reflectance of the surface as a function of phase angle. We selected
  six regions of interest (ROIs) and derived the phase curves for each
  ROI. We fit a linear-exponential function to the phase curves. The
  resulting model parameters were then interpreted by spectrophotometric,
  geomorphological, and phase-ratio analyses, and by investigating the
  influence of structural and textural properties of the surface. <BR />
  Results: We find evidence for the opposition effect (deviation of the
  phase curve from linear behavior) in phase curves for all areas. We
  found an anticorrelation between the phase ratio and reflectance in a
  small phase angle range. This provides evidence for the shadow-hiding
  effect. We conclude that the decrease in the slope of the phase ratio
  versus reflectance indicates a decrease in the proportion of shadowed
  regions and reduces the contribution of the shadow-hiding effect. Large
  uncertainties in the determination of the opposition effect parameters
  with respect to wavelength do not allow us to conclusively claim
  coherent backscattering in the opposition effect phenomenon. Based on
  the two analyses, we conclude that the opposition effect of comet 67P
  in the Ash-Khepry-Imhotep region is mainly affected by shadow-hiding.

---------------------------------------------------------
Title: Spectrophotometric variegation of the layering in comet
    67P/Churyumov-Gerasimenko as seen by OSIRIS
Authors: Tognon, G.; Ferrari, S.; Penasa, L.; La Forgia, F.; Massironi,
   M.; Naletto, G.; Lazzarin, M.; Cambianica, P.; Lucchetti, A.; Pajola,
   M.; Ferri, F.; Güttler, C.; Davidsson, B.; Deshapriya, P.; Fornasier,
   S.; Mottola, S.; Tóth, I.; Sierks, H.; Lamy, P. L.; Rodrigo, R.;
   Koschny, D.; Barbieri, C.; Barucci, M. A.; Bertaux, J. -L.; Bertini,
   I.; Bodewits, D.; Cremonese, G.; Da Deppo, V.; Debei, S.; De Cecco,
   M.; Deller, J.; Franceschi, M.; Frattin, E.; Fulle, M.; Gutiérrez,
   P. J.; Ip, W. -H.; Keller, H. U.; Lara, L. M.; López-Moreno, J. J.;
   Marzari, F.; Petropoulou, V.; Shi, X.; Tubiana, C.
2019A&A...630A..16T    Altcode:
  Context. Between August 2014 and September 2016, the ESA space
  mission Rosetta escorted comet 67P/Churyumov-Gerasimenko (67P)
  during its perihelion passage. The onboard OSIRIS Narrow Angle
  Camera (NAC) acquired high-resolution multispectral images of the
  cometary surface. These datasets allowed a characterization of
  the spectrophotometric variegation of the layering of the large
  lobe, correlated with the layer structural elevation. <BR /> Aims:
  We perform a spectrophotometric characterization of the outcropping
  stratification of the small lobe of 67P as a function of its structural
  elevation, and consequently, a spectrophotometric comparison of the
  layered outcrops of the two lobes. <BR /> Methods: We selected two
  sequences of post-perihelion OSIRIS NAC images ( 2.4 au outbound
  tothe Sun), from which we built up two multispectral images, framing
  an extended geological section of the onion-like stratification of
  the small lobe. Then we classified the consolidated areas of the
  outcropping and the relative coarse deposits that were identified
  in the multispectral data with a two-class maximum likelihood
  method. For this, we defined the classes as a function of the
  structural elevation of the surface. <BR /> Results: As a result,
  we identified a brightness variegation of the surface reflectance
  that is correlated with the structural elevation. The outer class,
  which is located at higher elevations, appears darker than the
  inner class. This fits previously obtained results for the large
  lobe. The reflectance values of the nucleus of 67P tend to decrease
  with increasing structural elevation. <BR /> Conclusions: The observed
  spectrophotometric variegation can be due to a different texture as well
  as to a different content of volatiles and refractories. We suggest
  that the outer outcrops appear darker because they have been exposed
  longer, and the inner outcrops appear brighter because the surface
  has been more effectively rejuvenated. We interpret this variegation
  as the result of an evolutionary process.

---------------------------------------------------------
Title: A catalog of stereo anaglyphs of comet
    67P/Churyumov-Gerasimenko - Application to the detection of deep
    ice pits
Authors: Lamy, Philippe; Faury, Guillaume; Romeuf, David; Groussin,
   Olivier; Durand, Joelle
2019EPSC...13..719L    Altcode:
  The OSIRIS/NAC camera aboard the Rosetta spacecraft has acquired
  approximately 27000 images of comet 67P/Churyumov-Gerasimenko at spatial
  scales down to a few centimeters. We exploit the numerous sequences of
  images separated by a few minutes suitable for stereo reconstructions
  to produce anaglyphs offering three-dimensional views of the comet,
  complementary to other technics, as a tool to understand the topography
  of the nucleus. Each anaglyph is documented by a set of 17 parameters
  which provide the contextual information. Over 1400 anaglyphs have
  been produced and cataloged so far; they are available on a dedicated
  website and can be searched using the associated parameters. As
  a first application, we present direct evidences of sub-surface
  ice at the bottom of deep pits, so-called "ice pits" identified on
  high-resolution anaglyphs. Their geometry and size are obtained from
  stereographic reconstruction. Both their high reflectivity and their
  blue color substantiate the presence of ice.

---------------------------------------------------------
Title: Coronal Mass Ejections over Solar Cycles 23 and 24
Authors: Lamy, P. L.; Floyd, O.; Boclet, B.; Wojak, J.; Gilardy, H.;
   Barlyaeva, T.
2019SSRv..215...39L    Altcode:
  We present a statistical analysis of solar coronal mass ejections
  (CMEs) based on 23 years of quasi-continuous observations with the
  LASCO coronagraph, thus covering two complete Solar Cycles (23 and
  24). We make use of five catalogs, one manual (CDAW) and four automated
  (ARTEMIS, CACTus, SEEDS, and CORIMP), to characterize the temporal
  evolutions and distributions of their properties: occurrence and mass
  rates, waiting times, periodicities, angular width, latitude, speed,
  acceleration and kinetic energy. Our analysis points to inevitable
  discrepancies between catalogs due to the complex nature of CMEs and to
  the different techniques implemented to detect them, but also to large
  areas of convergence that are critically important to ascertain the
  reliability of the results. The temporal variations of these properties
  are compared to four indices/proxies of solar activity: the radio
  flux at 10.7 cm (F10.7), the international sunspot number (SSN), the
  sunspot area (SSA), and the total magnetic field (TMF), either globally
  or separately in the northern and southern hemispheres in the case of
  the last three. We investigate the association of CMEs with flares,
  erupting prominences, active regions and streamers. We find that the
  CME occurrence and mass rates globally track the indices/proxies of
  solar activity with no time lag, prominently the radio flux F10.7, but
  the linear relationships were different during the two solar cycles,
  implying that the CME rates were relatively larger during SC 24 than
  during SC 23. However, there exists a pronounced divergence of the
  CME rates in the northern hemisphere during SC 24 as these rates were
  substantially larger than predicted by the temporal variation of the
  sunspot number. The distribution of kinetic energy follows a log-normal
  law and that of angular width follows an exponential law implying that
  they are random and independent. The distribution of waiting time
  (WTD) has a long power-law tail extending from 3 to 100 hr with a
  power-law index which varies with the solar cycle, thus reflecting
  the temporal variability of the process of CME formation. There is
  very limited evidence for periodicities in the occurrence and mass
  rates of CMEs, a striking feature being the dichotomy between the two
  hemispheres. Rather weak correlations are present among the various CME
  parameters and particularly none between speed and acceleration. The
  association of CMEs with flares and erupting prominences involves only
  a few percents of the overall population of CMEs but the associated
  CMEs have distinctly larger mass, speed, kinetic energy and angular
  width. A more pronounced association is found with active regions
  but the overwhelming one is with streamers further confirmed by the
  similarity between the heliolatitudinal distribution of CMEs and that
  of the electron density reconstructed from time-dependent tomographic
  inversion. We find no evidence of bimodality in the distributions of
  physical parameters that would support the existence of two classes,
  particularly that based on speed and acceleration, the distributions
  thus favoring a continuum of properties. There exists an excess of
  narrows CMEs which however does not define a special class. These
  narrow CMEs are likely associated with the ubiquitous mini-filaments
  eruptions and with mini flux ropes originating from small magnetic
  bipoles, the disruption mechanisms being similar to those launching
  larger CMEs. This supports the concept that CMEs at large arise from
  closed-field coronal regions at both large and small scales.

---------------------------------------------------------
Title: Tomography of the Solar Corona with the Wide-Field Imager
    for the Parker Solar Probe
Authors: Vásquez, Alberto M.; Frazin, Richard A.; Vourlidas, Angelos;
   Manchester, Ward B.; van der Holst, Bart; Howard, Russell A.; Lamy,
   Philippe
2019SoPh..294...81V    Altcode:
  The Wide-field Imager for the Parker Solar Probe (PSP/WISPR) comprises
  two telescopes that record white-light total brightness [B ] images of
  the solar corona. Their fields of view cover a widely changing range
  of heliocentric heights over the 24 highly eccentric orbits planned for
  the mission. In this work, the capability of PSP/WISPR data to carry out
  tomographic reconstructions of the three-dimensional (3D) distribution
  of the coronal electron density is investigated. Based on the precise
  orbital information of the mission, B -images for Orbits 1, 12, and 24
  are synthesized from a 3D magnetohydrodynamic model of the corona. For
  each orbit, the time series of synthetic images is used to carry out a
  tomographic reconstruction of the coronal electron density and results
  are compared with the model. As the PSP perihelion decreases, the range
  of heights that can be tomographically reconstructed progressively
  shifts to lower values, and the period required to gather the data
  decreases. For Orbit 1 tomographic reconstruction is not possible. For
  Orbit 12, tomographic reconstruction is possible in the heliocentric
  height range ≈5 -15 R<SUB>⊙</SUB>, over a region spanning up to
  ≈160<SUP>∘</SUP> in Carrington longitude, with data gathered over
  a ≈3.4 day-long period. For Orbit 24, tomographic reconstruction is
  possible in the heliocentric height range ≈3 -10 R<SUB>⊙</SUB>, over
  a region spanning up to ≈170<SUP>∘</SUP> in Carrington longitude,
  with data gathered over a ≈2.8 day-long period.

---------------------------------------------------------
Title: Multidisciplinary analysis of the Hapi region located on
    Comet 67P/Churyumov-Gerasimenko
Authors: Pajola, M.; Lee, J. -C.; Oklay, N.; Hviid, S. F.; Penasa, L.;
   Mottola, S.; Shi, X.; Fornasier, S.; Davidsson, B.; Giacomini, L.;
   Lucchetti, A.; Massironi, M.; Vincent, J. B.; Bertini, I.; Naletto,
   G.; Ip, W. H.; Sierks, H.; Lamy, P. L.; Rodrigo, R.; Koschny, D.;
   Keller, H. U.; Agarwal, J.; Barucci, M. A.; Bertaux, J. L.; Bodewits,
   D.; Cambianica, P.; Cremonese, G.; Da Deppo, V.; Debei, S.; De Cecco,
   M.; Deller, J.; El Maarry, M. R.; Feller, C.; Ferrari, S.; Fulle, M.;
   Gutierrez, P. J.; Güttler, C.; Lara, L. M.; La Forgia, F.; Lazzarin,
   M.; Lin, Z. -Y.; Lopez Moreno, J. J.; Marzari, F.; Preusker, F.;
   Scholten, F.; Toth, I.; Tubiana, C.
2019MNRAS.485.2139P    Altcode:
  By using the Rosetta/OSIRIS-NAC data set taken in 2014 August, we focus
  on the neck region, called Hapi, located on 67P Churyumov-Gerasimenko's
  Northern hemisphere. The gravitational potential and slopes of Hapi,
  coupled with the geological unit identification and the boulder
  size-frequency distributions, support the interpretation that both
  taluses and gravitational accumulation deposits observable on Hapi
  are the result of multiple cliff collapses that occurred at different
  times. By contrast, the fine-particle deposits observable in the
  central part of the study area are made of aggregates coming from the
  Southern hemisphere and deposited during each perihelion passage. Both
  the consolidated terrains on the western part of Hapi, as well as the
  centrally aligned ridge made of boulder-like features, suggest that
  Hapi is in structural continuity with the onion-like structure of
  the main lobe of 67P. Despite the dusty blanket observable on Hapi,
  its terrains are characterized by water-ice-rich components that,
  once repeatedly and rapidly illuminated, sublimate, hence resulting
  in the strong jet activity observed in 2014 August.

---------------------------------------------------------
Title: The shape of (7) Iris as evidence of an ancient large impact?
Authors: Hanuš, J.; Marsset, M.; Vernazza, P.; Viikinkoski, M.;
   Drouard, A.; Brož, M.; Carry, B.; Fetick, R.; Marchis, F.; Jorda, L.;
   Fusco, T.; Birlan, M.; Santana-Ros, T.; Podlewska-Gaca, E.; Jehin, E.;
   Ferrais, M.; Grice, J.; Bartczak, P.; Berthier, J.; Castillo-Rogez,
   J.; Cipriani, F.; Colas, F.; Dudziński, G.; Dumas, C.; Ďurech,
   J.; Kaasalainen, M.; Kryszczynska, A.; Lamy, P.; Le Coroller, H.;
   Marciniak, A.; Michalowski, T.; Michel, P.; Pajuelo, M.; Tanga, P.;
   Vachier, F.; Vigan, A.; Witasse, O.; Yang, B.
2019A&A...624A.121H    Altcode: 2019arXiv190209242H
  Context. Asteroid (7) Iris is an ideal target for disk-resolved imaging
  owing to its brightness (V 7-8) and large angular size of 0.33”
  during its apparitions. Iris is believed to belong to the category of
  large unfragmented asteroids that avoided internal differentiation,
  implying that its current shape and topography may record the first
  few 100 Myr of the solar system's collisional evolution. <BR /> Aims:
  We recovered information about the shape and surface topography of
  Iris from disk-resolved VLT/SPHERE/ZIMPOL images acquired in the
  frame of our ESO large program. <BR /> Methods: We used the All-Data
  Asteroid Modeling (ADAM) shape reconstruction algorithm to model the
  3D shape of Iris, using optical disk-integrated data and disk-resolved
  images from SPHERE and earlier AO systems as inputs. We analyzed the
  SPHERE images and our model to infer the asteroid's global shape and
  the morphology of its main craters. <BR /> Results: We present the
  3D shape, volume-equivalent diameter D<SUB>eq</SUB> = 214 ± 5 km,
  and bulk density ρ = 2.7 ± 0.3 g cm<SUP>-3</SUP> of Iris. Its shape
  appears to be consistent with that of an oblate spheroid with a large
  equatorial excavation. We identified eight putative surface features
  20-40 km in diameter detected at several epochs, which we interpret
  as impact craters, and several additional crater candidates. Craters
  on Iris have depth-to-diameter ratios that are similar to those of
  analogous 10 km craters on Vesta. <BR /> Conclusions: The bulk density
  of Iris is consistent with that of its meteoritic analog based on
  spectroscopic observations, namely LL ordinary chondrites. Considering
  the absence of a collisional family related to Iris and the number of
  large craters on its surface, we suggest that its equatorial depression
  may be the remnant of an ancient (at least 3 Gyr) impact. Iris's shape
  further opens the possibility that large planetesimals formed as almost
  perfect oblate spheroids. Finally, we attribute the difference in crater
  morphology between Iris and Vesta to their different surface gravities,
  and the absence of a substantial impact-induced regolith on Iris. <P
  />The reduced images are only available at the CDS via anonymous ftp to
  <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/624/A121">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/624/A121</A>Based
  on observations made with ESO Telescopes at the Paranal Observatory
  under programme ID 199.C-0074 (PI: P. Vernazza) and 086.C-0785 (PI:
  B. Carry).

---------------------------------------------------------
Title: VizieR Online Data Catalog: Asteroid (7) Iris Deconvolved
    disk-resolved images (Hanus+, 2019)
Authors: Hanus, J.; Marsset, M.; Vernazza, P.; Viikinkoski, M.;
   Drouard, A.; Broz, M.; Carry, B.; Fetick, R.; Marchis, F.; Jorda, L.;
   Fusco, T.; Birlan, M.; Santana-Ros, T.; Podlewska-Gaca, E.; Jehin, E.;
   Ferrais, M.; Grice, J.; Bartczak, P.; Berthier, J.; Castillo-Rogez,
   J.; Cipriani, F.; Colas, F.; Dudzinski, G.; Dumas, C.; Durech,
   J.; Kaasalainen, M.; Kryszczynska, A.; Lamy, P.; Le Coroller, H.;
   Marciniak, A.; Michalowski, T.; Michel, P.; Pajuelo, M.; Tanga, P.;
   Vachier, F.; Vigan, A.; Witasse, O.; Yang, B.
2019yCat..36240121H    Altcode:
  Deconvolved disk-resolved images of asteroid (7) Iris from Keck/Nirc2,
  VLT/NaCo and VLT/SPHERE/Zimpol instruments listed in Table C.2. The
  final shape model is based on the VLT/SPHERE/Zimpol data and a subset of
  the Keck/Nirc2 and VLT.NaCo data. The remaining data of a poor quality,
  often affected by deconvolution artifact, were used for consistency
  check only. The ordering of the data corresponds to the ordering in
  Table C2. <P />(2 data files).

---------------------------------------------------------
Title: VizieR Online Data Catalog: SPHERE/ZIMPOL (41) Daphne images
    (Carry+, 2019)
Authors: Carry, B.; Vachier, F.; Berthier, J.; Marsset, M.; Vernazza,
   P.; Grice, J.; Merline, W. J.; Lagadec, E.; Fienga, A.; Conrad, A.;
   Podlewska-Gaca, E.; Santana-Ros, T.; Viikinkoski, M.; Hanus, J.;
   Dumas, C.; Drummond, J. D.; Tamblyn, P. M.; Chapman, C. R.; Behrend,
   R.; Bernasconi, L.; Bartczak, P.; Benkhaldoun, Z.; Birlan, M.;
   Castillo-Rogez, J.; Cipriani, F.; Colas, F.; Drouard, A.; Durech, J.;
   Enke, B. L.; Fauvaud, S.; Ferrais, M.; Fetick, R.; Fusco, T.; Gillon,
   M.; Jehin, E.; Jorda, L.; Kaasalainen, M.; Keppler, M.; Kryszczynska,
   A.; Lamy, P.; Marchis, F.; Marciniak, A.; Michalowski, T.; Michel,
   P.; Pajuelo, M.; Tanga, P.; Vigan, A.; Warner, B.; Witasse, O.; Yang,
   B.; Zurlo, A.
2019yCat..36230132C    Altcode:
  Daphne was observed with the SPHERE instrument (ESO/VLT) around its
  opposition at eight different epochs. We used ZIMPOL in narrowband
  imaging mode (N_R filter; filter central wavelength = 645.9nm, width
  = 56.7nm). Each observational sequence consisted of a series of
  five images, where each image corresponded to a series of detector
  integration times (DITs) of 10s, during which Julia was used as a
  natural guide star for adaptive optics (AO) corrections. Observations
  were performed under good seeing conditions (&lt;=0.8") with an airmass
  usually below 1.6. After every asteroid observation, we observed a
  nearby star for deconvolution purposes to estimate the instrument point
  spread function (PSF). Finally, standard calibrations, which include
  detector flat-fields and darks, were acquired in the morning as part
  of the instrument calibration plan. <P />For a full description of the
  parameters, see: https://astro.troja.mff.cuni.cz/projects/asteroids3D/\
  web.php?page=db_description and Durech
  et al. (2010A&amp;A...513A..46D) <P />object:
  -------------------------------------------------------------------
  Planet Name H Diam i e a mag km deg AU
  -------------------------------------------------------------------
  41 Daphne 7.12 187.0 15.792100 0.27541753 2.76043870
  -------------------------------------------------------------------
  <P />(5 data files).

---------------------------------------------------------
Title: Closing the gap between Earth-based and interplanetary mission
observations: Vesta seen by VLT/SPHERE
Authors: Fétick, R. JL.; Jorda, L.; Vernazza, P.; Marsset,
   M.; Drouard, A.; Fusco, T.; Carry, B.; Marchis, F.; Hanuš,
   J.; Viikinkoski, M.; Birlan, M.; Bartczak, P.; Berthier, J.;
   Castillo-Rogez, J.; Cipriani, F.; Colas, F.; Dudziński, G.; Dumas, C.;
   Ferrais, M.; Jehin, E.; Kaasalainen, M.; Kryszczynska, A.; Lamy, P.;
   Le Coroller, H.; Marciniak, A.; Michalowski, T.; Michel, P.; Mugnier,
   L. M.; Neichel, B.; Pajuelo, M.; Podlewska-Gaca, E.; Santana-Ros,
   T.; Tanga, P.; Vachier, F.; Vigan, A.; Witasse, O.; Yang, B.
2019A&A...623A...6F    Altcode: 2019arXiv190201287F
  Context. Over the past decades, several interplanetary missions
  have studied small bodies in situ, leading to major advances in our
  understanding of their geological and geophysical properties. These
  missions, however, have had a limited number of targets. Among them,
  the NASA Dawn mission has characterised in detail the topography and
  albedo variegation across the surface of asteroid (4) Vesta down
  to a spatial resolution of ~20 m pixel<SUP>-1</SUP> scale. <BR />
  Aims: Here our aim was to determine how much topographic and albedo
  information can be retrieved from the ground with VLT/SPHERE in the
  case of Vesta, having a former space mission (Dawn) providing us with
  the ground truth that can be used as a benchmark. <BR /> Methods:
  We observed Vesta with VLT/SPHERE/ZIMPOL as part of our ESO large
  programme (ID 199.C-0074) at six different epochs, and deconvolved
  the collected images with a parametric point spread function (PSF). We
  then compared our images with synthetic views of Vesta generated from
  the 3D shape model of the Dawn mission, on which we projected Vesta's
  albedo information. <BR /> Results: We show that the deconvolution of
  the VLT/SPHERE images with a parametric PSF allows the retrieval of
  the main topographic and albedo features present across the surface of
  Vesta down to a spatial resolution of ~20-30 km. Contour extraction
  shows an accuracy of ~1 pixel (3.6 mas). The present study provides
  the very first quantitative estimate of the accuracy of ground-based
  adaptive-optics imaging observations of asteroid surfaces. <BR />
  Conclusions: In the case of Vesta, the upcoming generation of
  30-40 m telescopes (ELT, TMT, GMT) should in principle be able
  to resolve all of the main features present across its surface,
  including the troughs and the north-south crater dichotomy, provided
  that they operate at the diffraction limit. <P />Reduced images of
  Table A.1 are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/623/A6">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/623/A6</A>
  <P />Based on observations made with ESO Telescopes at the Paranal
  Observatory under programme ID 199.C-0074 (PI: P. Vernazza).

---------------------------------------------------------
Title: Homogeneous internal structure of CM-like asteroid (41) Daphne
Authors: Carry, B.; Vachier, F.; Berthier, J.; Marsset, M.; Vernazza,
   P.; Grice, J.; Merline, W. J.; Lagadec, E.; Fienga, A.; Conrad, A.;
   Podlewska-Gaca, E.; Santana-Ros, T.; Viikinkoski, M.; Hanuš, J.;
   Dumas, C.; Drummond, J. D.; Tamblyn, P. M.; Chapman, C. R.; Behrend,
   R.; Bernasconi, L.; Bartczak, P.; Benkhaldoun, Z.; Birlan, M.;
   Castillo-Rogez, J.; Cipriani, F.; Colas, F.; Drouard, A.; Ďurech, J.;
   Enke, B. L.; Fauvaud, S.; Ferrais, M.; Fetick, R.; Fusco, T.; Gillon,
   M.; Jehin, E.; Jorda, L.; Kaasalainen, M.; Keppler, M.; Kryszczynska,
   A.; Lamy, P.; Marchis, F.; Marciniak, A.; Michalowski, T.; Michel,
   P.; Pajuelo, M.; Tanga, P.; Vigan, A.; Warner, B.; Witasse, O.; Yang,
   B.; Zurlo, A.
2019A&A...623A.132C    Altcode: 2019arXiv190101890C
  Context. CM-like asteroids (Ch and Cgh classes) are a major population
  within the broader C-complex, encompassing about 10% of the mass of
  the main asteroid belt. Their internal structure has been predicted to
  be homogeneous, based on their compositional similarity as inferred
  from spectroscopy and numerical modeling of their early thermal
  evolution. <BR /> Aims: Here we aim to test this hypothesis by deriving
  the density of the CM-like asteroid (41) Daphne from detailed modeling
  of its shape and the orbit of its small satellite. <BR /> Methods:
  We observed Daphne and its satellite within our imaging survey with
  the Very Large Telescope extreme adaptive-optics SPHERE/ZIMPOL camera
  and complemented this data set with earlier Keck/NIRC2 and VLT/NACO
  observations. We analyzed the dynamics of the satellite with our
  Genoid meta-heuristic algorithm. Combining our high-angular resolution
  images with optical lightcurves and stellar occultations, we determine
  the spin period, orientation, and 3D shape, using our ADAM shape
  modeling algorithm. <BR /> Results: The satellite orbits Daphne on an
  equatorial, quasi-circular, prograde orbit, like the satellites of many
  other large main-belt asteroids. The shape model of Daphne reveals
  several large flat areas that could be large impact craters. The
  mass determined from this orbit combined with the volume computed
  from the shape model implies a density for Daphne of 1.77 ± 0.26 g
  cm<SUP>-3</SUP> (3 σ). This densityis consistent with a primordial
  CM-like homogeneous internal structure with some level of macroporosity
  (≈ 17%). <BR /> Conclusions: Based on our analysis of the density
  of Daphne and 75 other Ch/Cgh-type asteroids gathered from the
  literature, we conclude that the primordial internal structure of the
  CM parent bodies was homogeneous. <P />Based on observations made with
  (1) ESO Telescopes at the La Silla Paranal Observatory under programs <A
  href="http://archive.eso.org/wdb/wdb/eso/sched_rep_arc/query?progid=281.C-5011(A)">http://281.C-5011</A>
  (PI Dumas), <A
  href="http://archive.eso.org/wdb/wdb/eso/sched_rep_arc/query?progid=099.D-0098(A)">http://099.D-0098</A>
  (SPHERE GTO), and <A
  href="http://archive.eso.org/wdb/wdb/eso/abstract/query?progid=199.C-0074(A)">http://199.C-0074(A)</A>
  (PI Vernazza); and (2) the W. M. Keck Observatory, which is
  operated as a scientific partnership among the California
  Institute of Technology, the University of California
  and the National Aeronautics and Space Administration. The
  Observatory was made possible by the generous financial support
  of the W. M. Keck Foundation.The reduced and deconvolved
  AO images and the 3D shape model are publicly available at <A
  href="http://observations.lam.fr/astero/">http://observations.lam.fr/astero/</A>
  and at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/623/A132">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/623/A132</A>

---------------------------------------------------------
Title: A catalog of stereo anaglyphs of the nucleus of comet
    67P/Churyumov-Gerasimenko
Authors: Lamy, Philippe; Faury, Guillaume; Romeuf, David; Groussin,
   Olivier; Durand, Joelle; Beigbeder, Laurent; Khum, Kea
2019arXiv190302324L    Altcode:
  The OSIRIS/NAC camera onboard the Rosetta spacecraft acquired
  approximately 27000 images of comet 67PChuryumov-Gerasimenko at spatial
  scales down to a few centimeters. Numerous sequences of images separated
  by a few minutes suitable to stereo reconstruction allowed producing
  anaglyphs. They offer three-dimensional views complementary to other
  technics as a tool to understand the topography of the nucleus. Each
  one is documented by a set of 17 parameters. Over 1820 anaglyphs are
  available on a dedicated website at https://rosetta-3dcomet.cnes.fr

---------------------------------------------------------
Title: VizieR Online Data Catalog: VLT/SPHERE/ZIMPOL images of Vesta
    (Fetick+, 2019)
Authors: Fetick, R. J.; Jorda, L.; Vernazza, P.; Marsset, M.; Drouard,
   A.; Fusco, T.; Carry, B.; Marchis, F.; Hanus, J.; Viikinkoski,
   M.; Birlan, M.; Bartczak, P.; Berthier, J.; Castillo-Rogez, J.;
   Cipriani, F.; Colas, F.; Dudzinski, G.; Dumas, C.; Ferrais, M.; Jehin,
   E.; Kaasalainen, M.; Kryszczynska, A.; Lamy, P.; Le Coroller, H.;
   Marciniak, A.; Michalowski, T.; Michel, P.; Mugnier, L. M.; Neichel,
   B.; Pajuelo, M.; Podlewska-Gaca, E.; Santana-Ros, T.; Tanga, P.;
   Vachier, F.; Vigan, A.; Witasse, O.; Yang, B.
2019yCat..36230006F    Altcode:
  Vesta observations with VLT/SPHERE/ZIMPOL as part of the ESO
  large programme (ID 199.C-0074, PI: P.Vernazza) at six different
  epochs. The provided data is a set of images in FITS format,
  whose names correspond to the SPHERE observation times. Each image
  is of size 1024x1024 pixels. ESO header for each FITS provides
  information about the observation. Note that many observations
  are available for each of the six epochs. <P />object.dat :
  --------------------------------------------------------------------
  Planet Name H Diam i e a mag km deg AU
  --------------------------------------------------------------------
  4 Vesta 3.20 468.3 7.141840 0.08874248 2.36126876 <P />(2 data files).

---------------------------------------------------------
Title: The backscattering ratio of comet 67P/Churyumov-Gerasimenko
    dust coma as seen by OSIRIS onboard Rosetta
Authors: Bertini, I.; La Forgia, F.; Fulle, M.; Tubiana, C.; Güttler,
   C.; Moreno, F.; Agarwal, J.; Munoz, O.; Mottola, S.; Ivanovsky, S.;
   Pajola, M.; Lucchetti, A.; Petropoulou, V.; Lazzarin, M.; Rotundi,
   A.; Bodewits, D.; Frattin, E.; Toth, I.; Masoumzadeh, N.; Kovacs,
   G.; Rinaldi, G.; Guirado, D.; Sierks, H.; Naletto, G.; Lamy, P.;
   Rodrigo, R.; Koschny, D.; Davidsson, B.; Barbieri, C.; Barucci, M. A.;
   Bertaux, J. -L.; Cambianica, P.; Cremonese, G.; Da Deppo, V.; Debei,
   S.; De Cecco, M.; Deller, J.; Ferrari, S.; Ferri, F.; Fornasier, S.;
   Gutierrez, P. J.; Hasselmann, P. H.; Ip, W. -H.; Keller, H. U.; Lara,
   L. M.; Lopez Moreno, J. J.; Marzari, F.; Massironi, M.; Penasa, L.;
   Shi, X.
2019MNRAS.482.2924B    Altcode: 2018MNRAS.tmp.2714B
  Remote sensing observations of dust particles ejected from comets
  provide important hints on the intimate nature of the materials
  composing these primitive objects. The measurement of dust coma
  backscattering ratio, BSR, defined as the ratio of the reflectance at
  phase angle 0° and 30°, helps tuning theoretical models aimed at
  solving the inverse scattering problem deriving information on the
  nature of the ejected particles. The Rosetta/OSIRIS camera sampled
  the coma phase function of comet 67P, with four series acquired at low
  phase angles from 2015 January to 2016 May. We also added previously
  published data to our analysis to increase the temporal resolution of
  our findings. We measured a BSR in the range ∼ [1.7-3.6], broader
  than the range found in literature from ground-based observations of
  other comets. We found that during the post-perihelion phase, the BSR
  is systematically larger than the classical cometary dust values only
  for nucleocentric distances smaller than ∼100 km. We explain this
  trend in terms of a cloud of chunks orbiting the nucleus at distances
  &lt;100 km ejected during perihelion and slowly collapsing on the
  nucleus over a few months because of the coma gas drag. This also
  implies that the threshold particle size for the dust phase function
  to become similar to the nucleus phase function is between 2.5 mm and
  0.1 m, taking into account previous Rosetta findings.

---------------------------------------------------------
Title: Three-Dimensional Views of the Nucleus of Comet
    67P/Churyumov-Gerasimenko - Application to the Characterization of
    Active Pits
Authors: Lamy, P.; Faury, G.; Romeuf, D.; Groussin, O.; Nebouy, D.
2018AGUFM.P23G3522L    Altcode:
  The Narrow Angle Camera (NAC) of the OSIRIS imaging system aboard
  ESA's Rosetta spacecraft has acquired approximately 25000 images of the
  surface of the nucleus of comet 67P/Churyumov-Gerasimenko at various
  spatial scales down to centimeters per pixel. The bulk of these images
  have been obtained in sequences and the combined displacement of the
  Rosetta orbiter along its trajectory and the rotation of the nucleus
  allow associating many pairs of images appropriate to stereoscopic
  viewing. This is achieved by constructing anaglyphs after rotating
  the images so that the relative shift appears horizontal. The shift
  is set to limit the parallax to approximately 2° (with a maximum
  value of 4°) for the foreground so as to avoid image deformation. A
  time of writing, approximately 1100 anaglyphs have been produced. In
  addition to offering spectacular stereoscopic views of the nucleus,
  these anaglyphs allow studying the topography of the nucleus at spatial
  scales unachievable by DTMs. Further coupling with spectral images,
  we have been able to locate ice patches at the bottom of several narrow
  pits which indicate the presence of sub-surface ice at depths of a few
  meters. These narrow pits are most likely the sources of collimated
  jets widely seen in the coma of 67PC-G.

---------------------------------------------------------
Title: Regional unit definition for the nucleus of comet
    67P/Churyumov-Gerasimenko on the SHAP7 model
Authors: Thomas, N.; El Maarry, M. R.; Theologou, P.; Preusker,
   F.; Scholten, F.; Jorda, L.; Hviid, S. F.; Marschall, R.; Kührt,
   E.; Naletto, G.; Sierks, H.; Lamy, P. L.; Rodrigo, R.; Koschny, D.;
   Davidsson, B.; Barucci, M. A.; Bertaux, J. L.; Bertini, I.; Bodewits,
   D.; Cremonese, G.; Da Deppo, V.; Debei, S.; De Cecco, M.; Fornasier,
   S.; Fulle, M.; Groussin, O.; Gutièrrez, P. J.; Güttler, C.; Ip,
   W. H.; Keller, H. U.; Knollenberg, J.; Lara, L. M.; Lazzarin, M.;
   Lòpez-Moreno, J. J.; Marzari, F.; Tubiana, C.; Vincent, J. B.
2018P&SS..164...19T    Altcode:
  The previously defined regions on the nucleus of comet
  67P/Churyumov-Gerasimenko have been mapped back onto the 3D SHAP7
  model of the nucleus (Preusker et al., 2017). The resulting regional
  definition is therefore self-consistent with boundaries that are well
  defined in 3 dimensions. The facets belonging to each region are
  provided as supplementary material. The shape model has then been
  used to assess inhomogeneity of nucleus surface morphology within
  individual regions. Several regions show diverse morphology. We
  propose sub-division of these regions into clearly identifiable units
  (sub-regions) and a comprehensive table is provided. The surface
  areas of each sub-region have been computed and statistics based on
  grouping of unit types are provided. The roughness of each region is
  also provided in a quantitative manner using a technique derived from
  computer graphics applications. The quantitative method supports the
  sub-region definition by showing that differences between sub-regions
  can be numerically justified.

---------------------------------------------------------
Title: (16) Psyche: A mesosiderite-like asteroid?
Authors: Viikinkoski, M.; Vernazza, P.; Hanuš, J.; Le Coroller,
   H.; Tazhenova, K.; Carry, B.; Marsset, M.; Drouard, A.; Marchis,
   F.; Fetick, R.; Fusco, T.; Ďurech, J.; Birlan, M.; Berthier, J.;
   Bartczak, P.; Dumas, C.; Castillo-Rogez, J.; Cipriani, F.; Colas,
   F.; Ferrais, M.; Grice, J.; Jehin, E.; Jorda, L.; Kaasalainen, M.;
   Kryszczynska, A.; Lamy, P.; Marciniak, A.; Michalowski, T.; Michel,
   P.; Pajuelo, M.; Podlewska-Gaca, E.; Santana-Ros, T.; Tanga, P.;
   Vachier, F.; Vigan, A.; Warner, B.; Witasse, O.; Yang, B.
2018A&A...619L...3V    Altcode: 2018arXiv181002771V
  Context. Asteroid (16) Psyche is the target of the NASA Psyche
  mission. It is considered one of the few main-belt bodies that
  could be an exposed proto-planetary metallic core and that would
  thus be related to iron meteorites. Such an association is however
  challenged by both its near- and mid-infrared spectral properties and
  the reported estimates of its density. <BR /> Aims: Here, we aim to
  refine the density of (16) Psyche to set further constraints on its
  bulk composition and determine its potential meteoritic analog. <BR />
  Methods: We observed (16) Psyche with ESO VLT/SPHERE/ZIMPOL as part of
  our large program (ID 199.C-0074). We used the high angular resolution
  of these observations to refine Psyche's three-dimensional (3D) shape
  model and subsequently its density when combined with the most recent
  mass estimates. In addition, we searched for potential companions around
  the asteroid. <BR /> Results: We derived a bulk density of 3.99 ± 0.26
  g cm<SUP>-3</SUP> for Psyche. While such density is incompatible at
  the 3-sigma level with any iron meteorites (∼7.8 g cm<SUP>-3</SUP>),
  it appears fully consistent with that of stony-iron meteorites such as
  mesosiderites (density ∼4.25 g cm<SUP>-3</SUP>). In addition, we found
  no satellite in our images and set an upper limit on the diameter of
  any non-detected satellite of 1460 ± 200 m at 150 km from Psyche (0.2%
  × R<SUB>Hill</SUB>, the Hill radius) and 800 ± 200 m at 2000 km (3% ×
  R<SUB>Hill</SUB>). <BR /> Conclusions: Considering that the visible and
  near-infrared spectral properties of mesosiderites are similar to those
  of Psyche, there is merit to a long-published initial hypothesis that
  Psyche could be a plausible candidate parent body for mesosiderites. <P
  />Based on observations made with 1) ESO Telescopes at the La Silla
  Paranal Observatory under programs 086.C-0785 (PI Carry) and 199.C-0074
  (PI Vernazza); and 2) the W. M. Keck Observatory, which is operated as
  a scientific partnership among the California Institute of Technology,
  the University of California and the National Aeronautics and Space
  Administration. The Observatory was made possible by the generous
  financial support of the W. M. Keck Foundation.Tables A1 and A2 and
  reduced images are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr/">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/619/L3">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/619/L3</A>

---------------------------------------------------------
Title: Models of Rosetta/OSIRIS 67P Dust Coma Phase Function
Authors: Moreno, F.; Guirado, D.; Muñoz, O.; Bertini, I.; Tubiana,
   C.; Güttler, C.; Fulle, M.; Rotundi, A.; Della Corte, V.; Ivanovski,
   S. L.; Rinaldi, G.; Bockelée-Morvan, D.; Zakharov, V. V.; Agarwal,
   J.; Mottola, S.; Toth, I.; Frattin, E.; Lara, L. M.; Gutiérrez,
   P. J.; Lin, Z. Y.; Kolokolova, L.; Sierks, H.; Naletto, G.; Lamy,
   P. L.; Rodrigo, R.; Koschny, D.; Davidsson, B.; Barucci, M. A.;
   Bertaux, J. -L.; Bodewits, D.; Cremonese, G.; Da Deppo, V.; Debei,
   S.; De Cecco, M.; Deller, J.; Fornasier, S.; Ip, W. -H.; Keller,
   H. U.; Lazzarin, M.; López-Moreno, J. J.; Marzari, F.; Shi, X.
2018AJ....156..237M    Altcode: 2018arXiv180910424M
  The phase function of the dust coma of comet 67P has been determined
  from Rosetta/OSIRIS images. This function shows a deep minimum at phase
  angles near 100°, and a strong backscattering enhancement. These
  two properties cannot be reproduced by regular models of cometary
  dust, most of them based on wavelength-sized and randomly oriented
  aggregate particles. We show, however, that an ensemble of oriented
  elongated particles of a wide variety of aspect ratios, with radii
  r ≳ 10 μm, and whose long axes are perpendicular to the direction
  of the solar radiation, are capable of reproducing the observed phase
  function. These particles must be absorbing, with an imaginary part
  of the refractive index of about 0.1 to match the expected geometric
  albedo, and with porosity in the 60%-70% range.

---------------------------------------------------------
Title: VizieR Online Data Catalog: (16) Psyche images (Viikinkoski+,
    2018)
Authors: Viikinkoski, M.; Vernazza, P.; Hanus, J.; Le Coroller,
   H.; Tazhenova, K.; Carry, B.; Marsset, M.; Drouard, A.; Marchis, F.;
   Fetick, R.; Fusco, T.; Durech, J.; Birlan, M.; Berthier, J.; Bartczak,
   P.; Dumas, C.; Castillo-Rogez, J.; Cipriani, F.; Colas, F.; Ferrais,
   M.; Grice, J.; Jehin, E.; Jorda, L.; Kaasalainen, M.; Kryszczynska,
   A.; Lamy, P.; Marciniak, A.; Michalowski, T.; Michel, P.; Pajuelo,
   M.; Podlewska-Gaca, E.; Santana-Ros, T.; Tanga, P.; Vachier, F.;
   Vigan, A.; Warner, B.; Witasse, O.; Yang, B.
2018yCat..36199003V    Altcode:
  We observed Psyche with VLT/SPHERE/ZIMPOL at five different epochs,
  close to its opposition. The data reduction was performed as described
  in Vernazza et al. (2018, A&amp;A, in press.). <P />(4 data files).

---------------------------------------------------------
Title: Periodic behaviour of coronal mass ejections, eruptive events,
    and solar activity proxies during solar cycles 23 and 24
Authors: Barlyaeva, Tatiana; Wojak, Julien; Lamy, Philippe; Boclet,
   Brice; Toth, Imre
2018JASTP.177...12B    Altcode: 2017arXiv170402336B
  We report on the parallel analysis of the periodic behaviour of coronal
  mass ejections (CMEs) based on 21 years [1996-2016] of observations
  with the SOHO/LASCO-C2 coronagraph, solar flares, prominences, and
  several proxies of solar activity. We consider values of the rates
  globally and whenever possible, distinguish solar hemispheres and solar
  cycles 23 and 24. Periodicities are investigated using both frequency
  (periodogram) and time-frequency (wavelet) analysis. We find that these
  different processes, in addition to following the ≈11-year Solar
  Cycle, exhibit diverse statistically significant oscillations with
  properties common to all solar, coronal, and heliospheric processes:
  variable periodicity, intermittence, asymmetric development in the
  northern and southern solar hemispheres, and largest amplitudes during
  the maximum phase of solar cycles, being more pronounced during solar
  cycle 23 than the weaker cycle 24. However, our analysis reveals an
  extremely complex and diverse situation. For instance, there exists
  very limited commonality for periods of less than one year. The few
  exceptions are the periods of 3.1-3.2 months found in the global
  occurrence rates of CMEs and in the sunspot area (SSA) and those of
  5.9-6.1 months found in the northern hemisphere. Mid-range periods of
  ≈1 and ≈2 years are more wide spread among the studied processes,
  but exhibit a very distinct behaviour with the first one being present
  only in the northern hemisphere and the second one only in the southern
  hemisphere. These periodic behaviours likely results from the complexity
  of the underlying physical processes, prominently the emergence of
  magnetic flux.

---------------------------------------------------------
Title: The impact crater at the origin of the Julia family detected
    with VLT/SPHERE?
Authors: Vernazza, P.; Brož, M.; Drouard, A.; Hanuš, J.;
   Viikinkoski, M.; Marsset, M.; Jorda, L.; Fetick, R.; Carry, B.;
   Marchis, F.; Birlan, M.; Fusco, T.; Santana-Ros, T.; Podlewska-Gaca,
   E.; Jehin, E.; Ferrais, M.; Bartczak, P.; Dudziński, G.; Berthier,
   J.; Castillo-Rogez, J.; Cipriani, F.; Colas, F.; Dumas, C.; Ďurech,
   J.; Kaasalainen, M.; Kryszczynska, A.; Lamy, P.; Le Coroller, H.;
   Marciniak, A.; Michalowski, T.; Michel, P.; Pajuelo, M.; Tanga, P.;
   Vachier, F.; Vigan, A.; Warner, B.; Witasse, O.; Yang, B.; Asphaug,
   E.; Richardson, D. C.; Ševeček, P.; Gillon, M.; Benkhaldoun, Z.
2018A&A...618A.154V    Altcode:
  Context. The vast majority of the geophysical and geological constraints
  (e.g., internal structure, cratering history) for main-belt asteroids
  have so far been obtained via dedicated interplanetary missions (e.g.,
  ESA Rosetta, NASA Dawn). The high angular resolution of SPHERE/ZIMPOL,
  the new-generation visible adaptive-optics camera at ESO VLT, implies
  that these science objectives can now be investigated from the ground
  for a large fraction of D ≥ 100 km main-belt asteroids. The sharp
  images acquired by this instrument can be used to accurately constrain
  the shape and thus volume of these bodies (hence density when combined
  with mass estimates) and to characterize the distribution and topography
  of D ≥ 30 km craters across their surfaces. <BR /> Aims: Here, via
  several complementary approaches, we evaluated the recently proposed
  hypothesis that the S-type asteroid (89) Julia is the parent body of a
  small compact asteroid family that formed via a cratering collisional
  event. <BR /> Methods: We observed (89) Julia with VLT/SPHERE/ZIMPOL
  throughout its rotation, derived its 3D shape, and performed a
  reconnaissance and characterization of the largest craters. We also
  performed numerical simulations to first confirm the existence of
  the Julia family and to determine its age and the size of the impact
  crater at its origin. Finally, we utilized the images/3D shape in
  an attempt to identify the origin location of the small collisional
  family. <BR /> Results: On the one hand, our VLT/SPHERE observations
  reveal the presence of a large crater (D ~ 75 km) in Julia's southern
  hemisphere. On the other hand, our numerical simulations suggest that
  (89) Julia was impacted 30-120 Myrs ago by a D ~ 8 km asteroid, thereby
  creating a D ≥ 60 km impact crater at the surface of Julia. Given the
  small size of the impactor, the obliquity of Julia and the particular
  orientation of the family in the (a,i) space, the imaged impact
  crater is likely to be the origin of the family. <BR /> Conclusions:
  New doors into ground-based asteroid exploration, namely, geophysics
  and geology, are being opened thanks to the unique capabilities of
  VLT/SPHERE. Also, the present work may represent the beginning of a new
  era of asteroid-family studies. In the fields of geophysics, geology,
  and asteroid family studies, the future will only get brighter with
  the forthcoming arrival of 30-40 m class telescopes like ELT, TMT, and
  GMT. <P />Based on observations made with ESO Telescopes at the Paranal
  Observatory under program ID 199.C-0074 (PI: P. Vernazza). <P />The
  reduced images are only available available at the CDS via anonymous ftp
  to <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (<A href="http://cdsarc.u-strasbg.fr">http://130.79.128.5</A>) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/618/A154">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/618/A154</A>

---------------------------------------------------------
Title: On deviations from free-radial outflow in the inner coma of
    comet 67P/Churyumov-Gerasimenko
Authors: Gerig, S. -B.; Marschall, R.; Thomas, N.; Bertini, I.;
   Bodewits, D.; Davidsson, B.; Fulle, M.; Ip, W. -H.; Keller, H. U.;
   Küppers, M.; Preusker, F.; Scholten, F.; Su, C. C.; Toth, I.; Tubiana,
   C.; Wu, J. -S.; Sierks, H.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.;
   Koschny, D.; Rickman, H.; Agarwal, J.; Barucci, M. A.; Bertaux, J. -L.;
   Cremonese, G.; Da Deppo, V.; Debei, S.; De Cecco, M.; Deller, J.;
   Fornasier, S.; Groussin, O.; Gutierrez, P. J.; Güttler, C.; Hviid,
   S. F.; Jorda, L.; Knollenberg, J.; Kramm, J. -R.; Kührt, E.; Lara,
   L. M.; Lazzarin, M.; Lopez Moreno, J. J.; Marzari, F.; Mottola, S.;
   Naletto, G.; Oklay, N.; Vincent, J. -B.
2018Icar..311....1G    Altcode:
  The Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS)
  onboard the European Space Agency's Rosetta spacecraft acquired images
  of comet 67P/Churyumov-Gerasimenko (67P) and its surrounding dust coma
  starting from May 2014 until September 2016. In this paper we present
  methods and results from analysis of OSIRIS images regarding the dust
  outflow in the innermost coma of 67P. The aim is to determine the global
  dust outflow behaviour and place constraints on physical processes
  affecting particles in the inner coma. We study the coma region right
  above the nucleus surface, spanning from the nucleus centre out to
  a distance of about 50 km comet centric distance (approximately 25
  average comet radii). We primarily adopt an approach used by Thomas
  and Keller (1990) to study the dust outflow. We present the effects
  on azimuthally-averaged values of the dust reflectance of non-radial
  flow and non-point-source geometry, acceleration of dust particles,
  sublimation of icy dust particles after ejection from the surface,
  dust particle fragmentation, optical depth effects and the influence
  of gravitationally bound particles. All of these physical processes
  could modify the observed distribution of light scattered by the dust
  coma. <P />In the image analysis, profiles of azimuthally averaged dust
  brightness as a function of impact parameter b (azimuthal average,
  "Ā-curve") were fitted with a simple function that best fits the
  shape of our profile curves (f(b ; u , v , w , z) = u /b<SUP>v</SUP>
  + wb + z). The analytical fit parameters (u, v, w, z), which hold
  the key information about the dust outflow behaviour, were saved in
  a comprehensive database. <P />Through statistical analysis of these
  information, we show that the spatial distribution of dust follows
  free-radial outflow behaviour (i.e. force-free radial outflow with
  constant velocity) beyond distances larger than ∼11.9 km from the
  comet centre, which corresponds to a relative distance of about 6
  average comet radii from the comet centre. Hence, we conclude that
  beyond this distance, and on average, fragmentation and gravitationally
  bound particles are negligible processes in determining the optically
  scattered light distribution in the innermost coma. Closer to the
  nucleus we observe dust outflow behaviour that deviates from free-radial
  outflow. <P />A comparison of our result profiles with numerical models
  using a Direct Simulation Monte Carlo (DSMC) approach with dust particle
  distributions calculated using a test particle approach has been used to
  demonstrate the influence of a complex shape and particle acceleration
  on the azimuthal average profiles. We demonstrate that, while other
  effects such as fragmentation or sublimation of dust particles cannot
  be ruled out, acceleration of the dust particles and effects arising
  from the shape of the irregular nucleus (non-point source geometry) are
  sufficient to explain the observed dust outflow behaviour from image
  data analysis. <P />As a by-product of this work, we have calculated
  "Afρ" values for the 1/r regime. We found a peak in the coma activity
  in terms of Afρ (normalised to a phase angle of 90°) of ∼210 cm
  20 days after perihelion. Furthermore, based on simplified models of
  particle motion within bound orbits, it is shown that limits on the
  total cross-sectional area of bound particles might be derived through
  further analysis. An example is given.

---------------------------------------------------------
Title: The big lobe of 67P/Churyumov-Gerasimenko comet: morphological
    and spectrophotometric evidences of layering as from OSIRIS data
Authors: Ferrari, Sabrina; Penasa, L.; La Forgia, F.; Massironi, M.;
   Naletto, G.; Lazzarin, M.; Fornasier, S.; Hasselmann, P. H.; Lucchetti,
   A.; Pajola, M.; Ferri, F.; Cambianica, P.; Oklay, N.; Tubiana, C.;
   Sierks, H.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Davidsson, B.;
   Barucci, M. A.; Bertaux, J. -L.; Bertini, I.; Bodewits, D.; Cremonese,
   G.; Da Deppo, V.; Debei, S.; De Cecco, M.; Deller, J.; Franceschi, M.;
   Frattin, E.; Fulle, M.; Groussin, O.; Gutiérrez, P. J.; Güttler, C.;
   Hviid, S. F.; Ip, W. -H.; Jorda, L.; Keller, H. U.; Knollenberg, J.;
   Kührt, E.; Küppers, M.; Lara, L. M.; López-Moreno, J. J.; Marzari,
   F.; Shi, X.; Simioni, E.; Thomas, N.; Vincent, J. -B.
2018MNRAS.479.1555F    Altcode: 2018MNRAS.tmp.1575F
  Between 2014 and 2016, ESA's Rosetta OSIRIS cameras acquired
  multiple-filters images of the layered nucleus of comet
  67P/Churyumov-Gerasimenko, ranging from ultraviolet to near-infrared
  wavelengths. No correlation between layers disposition and surface
  spectral variegation has been observed so far. This paper investigates
  possible spectral differences among decametre-thickness outcropping
  layers of the biggest lobe of the comet by means of OSIRIS image
  dataset. A two-classes maximum likelihood classification was
  applied on consolidated outcrops and relative deposits identified on
  post-perihelion multispectral images of the big lobe. We distinguished
  multispectral data on the basis of the structural elevation of the
  onion-shell Ellipsoidal Model of 67P. The spatial distribution of the
  two classes displays a clear dependence on the structural elevation,
  with the innermost class resulting over 50 per cent brighter than the
  outermost one. Consolidated cometary materials located at different
  structural levels are characterized by different brightness and revealed
  due to the selective removal of large volumes. This variegation can
  be attributed to a different texture of the outcrop surface and/or to
  a different content of refractory materials.

---------------------------------------------------------
Title: Evidence of cool prominence material embedded in CMEs from
    polarization measurements
Authors: Lamy, Philippe; Floyd, Olivier; Koutchmy, Serge
2018cosp...42E1930L    Altcode:
  In white-light coronagraph images, cool prominence material is
  sometimes observed as bright substructures or plasmoids in coronal mass
  ejections (CMEs). Based on observations of a CME with the SECCHI/STEREO
  coronagraphs on 31 August 2007, Mierla et al. (2011) have shown that
  the emission from such bright patches is characterized by very low
  polarization and was due to H-alpha radiation from cool prominence
  material. We have examined several polarization images of CMEs obtained
  with the LASCO-C2 coronagraph with its orange filter. This filter is
  approximately centered on the HeI D3 line. This low excitation line
  emission is superior to the H-alpha emission of HI because its FIP
  is much higher. In several cases, we observe very low-polarization
  components embedded in CMEs characterized by a much larger polarization
  resulting from the Thomson scattering. They most likely present evidence
  of cool prominence material carried by the CMEs.

---------------------------------------------------------
Title: VizieR Online Data Catalog: SPHERE/ZIMPOL (89) Julia images
    (Vernazza+, 2018)
Authors: Vernazza, P.; Brozv, M.; Drouard, A.; Hanusv, J.;
   Viikinkoski, M.; Marsset, M.; Jorda, L.; Fetick, R.; Carry, B.;
   Marchis, F.; Birlan, M.; Fusco, T.; Santana-Ros, T.; Podlewska-Gaca,
   E.; Jehin, E.; Ferrais, M.; Bartczak, P.; Dudzinski, G.; Berthier,
   J.; Castillo-Rogez, J.; Cipriani, F.; Colas, F.; Dumas, C.; Durech,
   J.; Kaasalainen, M.; Kryszczynska, A.; Lamy, P.; Le Coroller, H.;
   Marciniak, A.; Michalowski, T.; Michel, P.; Pajuelo, M.; Tanga, P.;
   Vachier, F.; Vigan, A.; Warner, B.; Witasse, O.; Yang, B.; Asphaug,
   E.; Richardson, D. C.; Svevevek, P.; Gillon, M.; Benkhaldoun, Z.
2018yCat..36180154V    Altcode:
  Julia was observed with the SPHERE instrument (ESO/VLT) around its
  opposition at eight different epochs. We used ZIMPOL in narrowband
  imaging mode (N_R filter; filter central wavelength = 645.9nm, width
  = 56.7nm). Each observational sequence consisted of a series of
  five images, where each image corresponded to a series of detector
  integration times (DITs) of 10s, during which Julia was used as a
  natural guide star for adaptive optics (AO) corrections. Observations
  were performed under good seeing conditions (&lt;=0.8") with an
  airmass usually below 1.6. After every asteroid observation, we
  observed a nearby star for deconvolution purposes to estimate the
  instrument point spread function (PSF). Finally, standard calibrations,
  which include detector flat-fields and darks, were acquired in the
  morning as part of the instrument calibration plan. <P />objects:
  -------------------------------------------------------------------
  Planet Name H Diam i e a mag km deg AU
  -------------------------------------------------------------------
  89 Julia 6.60 151.5 16.127006 0.18459430 2.55051892
  -------------------------------------------------------------------
  <P />(2 data files).

---------------------------------------------------------
Title: Three-Dimensional Views of the Nucleus of Comet
    67P/Churyumov-Gerasimenko - Application to the Characterization of
    Active Pits
Authors: Lamy, Philippe; Groussin, Olivier; Faury, Guillaume; Romeuf,
   David; Nebouy, David
2018cosp...42E1928L    Altcode:
  The Narrow Angle Camera (NAC) of the OSIRIS imaging system aboard
  ESA's Rosetta spacecraft has acquired approximately 25000 images of the
  surface of the nucleus of comet 67P/Churyumov-Gerasimenko at various
  spatial scales down to centimeters per pixel. The bulk of these images
  have been obtained in sequences and the combined displacement of the
  Rosetta orbiter along its trajectory and the rotation of the nucleus
  allow associating many pairs of images appropriate to stereoscopic
  viewing. This is achieved by constructing anaglyphs after rotating
  the images so that the relative shift appears horizontal. The shift
  is set to limit the parallax to approximately 2° (with a maximum
  value of 4°) for the foreground so as to avoid image deformation. A
  time of writing, approximately 1000 anaglyphs have been produced. In
  addition to offering spectacular stereoscopic views of the nucleus,
  these anaglyphs allow studying the topography of the nucleus at spatial
  scales unachievable by DTMs. Further coupling with spectral images,
  we have been able to locate ice patches at the bottom of several narrow
  pits which indicate the presence of sub-surface ice at depths of a few
  meters. These narrow pits are most likely the sources of collimated
  jets widely seen in the coma of 67PC-G.

---------------------------------------------------------
Title: Three-Dimensional Shape Reconstruction and Propagation of
    the CME of 22 October 2003 from LASCO Images
Authors: Lamy, Philippe
2018cosp...42E1929L    Altcode:
  The determination of the three-dimensional morphology and propagation
  of coronal mass ejections (CMEs) in coronagraphic white-light images
  has been a major question of coronal physics, and a challenge to the
  observers. The STEREO mission has so far provided the required two view
  points for stereoscopic reconstruction but that capability has ended
  with the loss of one of the S/C. Two-dimensional images as provided by
  the LASCO-C2 and C3 coronagraphs are generally insufficientto provide
  anything more than an idea of the global and internal structures
  of a CME. There are however favorable cases where the relatively
  simple morphology of a CME and the geometry of the observations allow
  perceiving its global shape. In those cases, forward modeling based on
  an a-priori shape model can be attempted, and the resulting synthetic
  images are compared and fitted to the observations. We present the
  case of the CME detected and tracked by LASCO on 22 October 2003 which
  is amenable to such an approach. The global shape of this CME on the
  images however requires the introduction of an elaborated shape model,
  an asymmetric plasma cloud. The images are first processed in order
  to remove most of the background or foreground coronal structures
  (essentially streamers) which are superimposed on the CME. Using
  the cloud model, we generate synthetic images that are fitted to
  the observed images. The resulting parameters allow a detailed
  characterization of the 3D shape and propagation of the CME.

---------------------------------------------------------
Title: Tensile strength of 67P/Churyumov-Gerasimenko nucleus material
    from overhangs (Corrigendum)
Authors: Attree, N.; Groussin, O.; Jorda, L.; Nébouy, D.; Thomas,
   N.; Brouet, Y.; Kührt, E.; Preusker, F.; Scholten, F.; Knollenberg,
   J.; Hartogh, P.; Sierks, H.; Barbieri, C.; Lamy, P.; Rodrigo, R.;
   Koschny, D.; Rickman, H.; Keller, H. U.; A'Hearn, M. F.; Auger,
   A. -T.; Barucci, M. A.; Bertaux, J. -L.; Bertini, I.; Bodewits, D.;
   Boudreault, S.; Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.;
   De Cecco, M.; Deller, J.; El-Maarry, M. R.; Fornasier, S.; Fulle, M.;
   Gutiérrez, P. J.; Güttler, C.; Hviid, S.; Ip, W. -H.; Kovacs, G.;
   Kramm, J. R.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Lopez Moreno,
   J. J.; Lowry, S.; Marchi, S.; Marzari, F.; Mottola, S.; Naletto, G.;
   Oklay, N.; Pajola, M.; Toth, I.; Tubiana, C.; Vincent, J. -B.; Shi, X.
2018A&A...614C...2A    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Coma morphology of comet 67P controlled by insolation over
    irregular nucleus
Authors: Shi, X.; Hu, X.; Mottola, S.; Sierks, H.; Keller, H. U.; Rose,
   M.; Güttler, C.; Fulle, M.; Fornasier, S.; Agarwal, J.; Pajola, M.;
   Tubiana, C.; Bodewits, D.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.;
   Koschny, D.; Barucci, M. A.; Bertaux, J. -L.; Bertini, I.; Boudreault,
   S.; Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco,
   M.; Deller, J.; Groussin, O.; Gutiérrez, P. J.; Hviid, S. F.; Ip,
   W. -H.; Jorda, L.; Knollenberg, J.; Kovacs, G.; Kramm, J. -R.; Kührt,
   E.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Lopez-Moreno, J. J.;
   Marzari, F.; Naletto, G.; Oklay, N.; Toth, I.; Vincent, J. -B.
2018NatAs...2..562S    Altcode: 2018NatAs.tmp...59S
  While the structural complexity of cometary comae is already
  recognizable from telescopic observations<SUP>1</SUP>, the innermost
  region, within a few radii of the nucleus, was not resolved until
  spacecraft exploration became a reality<SUP>2,3</SUP>. The dust coma
  displays jet-like features of enhanced brightness superposed on a
  diffuse background<SUP>1,4,5</SUP>. Some features can be traced to
  specific areas on the nucleus, and result conceivably from locally
  enhanced outgassing and/or dust emission<SUP>6-8</SUP>. However,
  diffuse or even uniform activity over topographic concavity can
  converge to produce jet-like features<SUP>9,10</SUP>. Therefore,
  linking observed coma morphology to the distribution of activity on
  the nucleus is difficult<SUP>11,12</SUP>. Here, we study the emergence
  of dust activity at sunrise on comet 67P/Churyumov-Gerasimenko using
  high-resolution, stereo images from the OSIRIS camera onboard the
  Rosetta spacecraft, where the sources and formation of the jet-like
  features are resolved. We perform numerical simulations to show that
  the ambient dust coma is driven by pervasive but non-uniform water
  outgassing from the homogeneous surface layer. Physical collimations
  of gas and dust flows occur at local maxima of insolation and also
  via topographic focusing. Coma structures are projected to exhibit
  jet-like features that vary with the perspective of the observer. For
  an irregular comet such as 67P/Churyumov-Gerasimenko, near-nucleus
  coma structures can be concealed in the shadow of the nucleus, which
  further complicates the picture.

---------------------------------------------------------
Title: The phase function and density of the dust observed at comet
    67P/Churyumov-Gerasimenko
Authors: Fulle, Marco; Bertini, I.; Della Corte, V.; Güttler, C.;
   Ivanovski, S.; La Forgia, F.; Lasue, J.; Levasseur-Regourd, A. C.;
   Marzari, F.; Moreno, F.; Mottola, S.; Naletto, G.; Palumbo, P.;
   Rinaldi, G.; Rotundi, A.; Sierks, H.; Barbieri, C.; Lamy, P. L.;
   Rodrigo, R.; Koschny, D.; Rickman, H.; Barucci, M. A.; Bertaux,
   J. -L.; Bodewits, D.; Cremonese, G.; Da Deppo, V.; Davidsson, B.;
   Debei, S.; De Cecco, M.; Deller, J.; Fornasier, S.; Groussin, O.;
   Gutiérrez, P. J.; Hviid, H. S.; Ip, W. H.; Jorda, L.; Keller, H. U.;
   Knollenberg, J.; Kramm, J. R.; Kührt, E.; Küppers, M.; Lara, M. L.;
   Lazzarin, M.; López-Moreno, J. J.; Shi, X.; Thomas, N.; Tubiana, C.
2018MNRAS.476.2835F    Altcode: 2018MNRAS.tmp..454F
  The OSIRIS camera onboard Rosetta measured the phase function of both
  the coma dust and the nucleus. The two functions have a very different
  slope versus the phase angle. Here, we show that the nucleus phase
  function should be adopted to convert the brightness to the size of dust
  particles larger than 2.5 mm only. This makes the dust bursts observed
  close to Rosetta by OSIRIS, occurring about every hour, consistent
  with the fragmentation on impact with Rosetta of parent particles,
  whose flux agrees with the dust flux observed by GIADA. OSIRIS also
  measured the antisunward acceleration of the fragments, thus providing
  the first direct measurement of the solar radiation force acting
  on the dust fragments and thus of their bulk density, excluding any
  measurable rocket effect by the ice sublimation from the dust. The
  obtained particle density distribution has a peak matching the bulk
  density of most COSIMA particles, and represents a subset of the density
  distribution measured by GIADA. This implies a bias in the elemental
  abundances measured by COSIMA, which thus are consistent with the 67P
  dust mass fractions inferred by GIADA, i.e. (38 ± 8) {per cent} of
  hydrocarbons versus the (62 ± 8) {per cent} of sulphides and silicates.

---------------------------------------------------------
Title: Exposed bright features on the comet 67P/Churyumov-Gerasimenko:
    distribution and evolution
Authors: Deshapriya, J. D. P.; Barucci, M. A.; Fornasier, S.;
   Hasselmann, P. H.; Feller, C.; Sierks, H.; Lucchetti, A.; Pajola,
   M.; Oklay, N.; Mottola, S.; Masoumzadeh, N.; Tubiana, C.; Güttler,
   C.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.;
   Bertaux, J. -L.; Bertini, I.; Bodewits, D.; Boudreault, S.; Cremonese,
   G.; Da Deppo, V.; Davidsson, B. J. R.; Debei, S.; De Cecco, M.; Deller,
   J.; Fulle, M.; Groussin, O.; Gutierrez, P. J.; Hoang, H. V.; Hviid,
   S. F.; Ip, W.; Jorda, L.; Keller, H. U.; Knollenberg, J.; Kramm,
   R.; Kührt, E.; Küppers, M.; Lara, L.; Lazzarin, M.; Lopez Moreno,
   J. J.; Marzari, F.; Naletto, G.; Preusker, F.; Shi, X.; Thomas, N.;
   Vincent, J. -B.
2018A&A...613A..36D    Altcode:
  Context. Since its arrival at the comet 67P/Churyumov-Gerasimenko
  in August 2014, the Rosetta spacecraft followed the comet as it went
  past the perihelion and beyond until September 2016. During this time
  there were many scientific instruments operating on board Rosetta
  to study the comet and its evolution in unprecedented detail. In
  this context, our study focusses on the distribution and evolution
  of exposed bright features that have been observed by OSIRIS, which
  is the scientific imaging instrument aboard Rosetta. <BR /> Aims:
  We envisage investigating various morphologies of exposed bright
  features and the mechanisms that triggered their appearance. <BR />
  Methods: We co-registered multi-filter observations of OSIRIS images
  that are available in reflectance. The Lommel-Seeliger disk function
  was used to correct for the illumination conditions and the resulting
  colour cubes were used to perform spectrophotometric analyses on
  regions of interest. <BR /> Results: We present a catalogue of 57
  exposed bright features observed on the nucleus of the comet, all
  of which are attributed to the presence of H<SUB>2</SUB>O ice on the
  comet. Furthermore, we categorise these patches under four different
  morphologies and present geometric albedos for each category. <BR />
  Conclusions: Although the nucleus of 67P/Churyumov-Gerasimenko appears
  to be dark in general, there are localised H<SUB>2</SUB>O ice sources
  on the comet. Cometary activity escalates towards the perihelion passage
  and reveals such volatile ices. We propose that isolated H<SUB>2</SUB>O
  ice patches found in smooth terrains in regions, such as Imhotep, Bes,
  and Hapi, result from frost as an aftermath of the cessation of the
  diurnal water cycle on the comet as it recedes from perihelion. Upon
  the comet's return to perihelion, such patches are revealed when
  sublimation-driven erosion removes the thin dust layers that got
  deposited earlier. More powerful activity sources such as cometary
  outbursts are capable of revealing much fresher, less contaminated
  H<SUB>2</SUB>O ice that is preserved with consolidated cometary
  material, as observed on exposed patches resting on boulders. This is
  corroborated by our albedo calculations that attribute higher albedos
  for bright features with formations related to outbursts.

---------------------------------------------------------
Title: Tensile strength of 67P/Churyumov-Gerasimenko nucleus material
    from overhangs
Authors: Attree, N.; Groussin, O.; Jorda, L.; Nébouy, D.; Thomas,
   N.; Brouet, Y.; Kührt, E.; Preusker, F.; Scholten, F.; Knollenberg,
   J.; Hartogh, P.; Sierks, H.; Barbieri, C.; Lamy, P.; Rodrigo, R.;
   Koschny, D.; Rickman, H.; Keller, H. U.; A'Hearn, M. F.; Auger,
   A. -T.; Barucci, M. A.; Bertaux, J. -L.; Bertini, I.; Bodewits, D.;
   Boudreault, S.; Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.;
   De Cecco, M.; Deller, J.; El-Maarry, M. R.; Fornasier, S.; Fulle, M.;
   Gutiérrez, P. J.; Güttler, C.; Hviid, S.; Ip, W. -H.; Kovacs, G.;
   Kramm, J. R.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Lopez Moreno,
   J. J.; Lowry, S.; Marchi, S.; Marzari, F.; Mottola, S.; Naletto, G.;
   Oklay, N.; Pajola, M.; Toth, I.; Tubiana, C.; Vincent, J. -B.; Shi, X.
2018A&A...611A..33A    Altcode: 2017arXiv171207508A
  We directly measured twenty overhanging cliffs on the surface of comet
  67P/Churyumov-Gerasimenko extracted from the latest shape model and
  estimated the minimum tensile strengths needed to support them against
  collapse under the comet's gravity. We find extremely low strengths
  of around 1 Pa or less (1 to 5 Pa, when scaled to a metre length). The
  presence of eroded material at the base of most overhangs, as well as
  the observed collapse of two features andthe implied previous collapse
  of another, suggests that they are prone to failure and that the true
  material strengths are close to these lower limits (although we only
  consider static stresses and not dynamic stress from, for example,
  cometary activity). Thus, a tensile strength of a few pascals is a good
  approximation for the tensile strength of the 67P nucleus material,
  which is in agreement with previous work. We find no particular trends
  in overhang properties either with size over the 10-100 m range studied
  here or location on the nucleus. There are no obvious differences,
  in terms of strength, height or evidence of collapse, between the
  populations of overhangs on the two cometary lobes, suggesting that
  67P is relatively homogenous in terms of tensile strength. Low material
  strengths are supportive of cometary formation as a primordial rubble
  pile or by collisional fragmentation of a small body (tens of km).

---------------------------------------------------------
Title: Meter-scale thermal contraction crack polygons on the nucleus
    of comet 67P/Churyumov-Gerasimenko
Authors: Auger, A. -T.; Groussin, O.; Jorda, L.; El-Maarry, M. R.;
   Bouley, S.; Séjourné, A.; Gaskell, R.; Capanna, C.; Davidsson,
   B.; Marchi, S.; Höfner, S.; Lamy, P. L.; Sierks, H.; Barbieri,
   C.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller, H. U.; Agarwal,
   J.; A'Hearn, M. F.; Barucci, M. A.; Bertaux, J. -L.; Bertini, I.;
   Cremonese, G.; Da Deppo, V.; Debei, S.; De Cecco, M.; Fornasier, S.;
   Fulle, M.; Gutiérrez, P. J.; Güttler, C.; Hviid, S.; Ip, W. -H.;
   Knollenberg, J.; Kramm, J. -R.; Kührt, E.; Küppers, M.; Lara,
   L. M.; Lazzarin, M.; Lopez Moreno, J. J.; Marzari, F.; Massironi,
   M.; Michalik, H.; Naletto, G.; Oklay, N.; Pommerol, A.; Sabau, L.;
   Thomas, N.; Tubiana, C.; Vincent, J. -B.; Wenzel, K. -P.
2018Icar..301..173A    Altcode:
  We report on the detection and characterization of more
  than 6300 polygons on the surface of the nucleus of comet
  67P/Churyumov-Gerasimenko, using images acquired by the OSIRIS camera
  onboard Rosetta between August 2014 and March 2015. They are found
  in consolidated terrains and grouped in localized networks. They are
  present at all latitudes (from North to South) and longitudes (head,
  neck, and body), sometimes on pit walls or following lineaments. About
  1.5% of the observed surface is covered by polygons. Polygons have
  an homogeneous size across the nucleus, with 90% of them in the size
  range 1 - 5 m and a mean size of 3.0 ± 1.4 m. They show different
  morphologies, depending on the width and depth of their trough. They are
  found in networks with 3- or 4-crack intersection nodes. The polygons
  observed on 67P are consistent with thermal contraction crack polygons
  formed by the diurnal or seasonal temperature variations in a hard
  (MPa) and consolidated sintered layer of water ice, located a few
  centimeters below the surface. Our thermal analysis shows an evolution
  of thermal contraction crack polygons according to the local thermal
  environment, with more evolved polygons (i.e. deeper and larger troughs)
  where the temperature and the diurnal and seasonal temperature range
  are the highest. Thermal contraction crack polygons are young surface
  morphologies that probably formed after the injection of 67P in the
  inner solar system, typically 100,000 years ago, and could be as young
  as a few orbital periods, following the decreasing of its perihelion
  distance in 1959 from 2.7 to 1.3 a.u. Meter scale thermal contraction
  crack polygons should be common features on the nucleus of Jupiter
  family comets.

---------------------------------------------------------
Title: Thermophysics of fractures on comet 67P/Churyumov-Gerasimenko
Authors: Höfner, S.; Vincent, J. -B.; Blum, J.; Davidsson, B. J. R.;
   Sierks, H.; El-Maarry, M. R.; Deller, J.; Hofmann, M.; Hu, X.; Pajola,
   M.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman,
   H.; Keller, H. U.; A'Hearn, M. F.; Auger, A. -T.; Barucci, M. A.;
   Bertaux, J. -L.; Bertini, I.; Bodewits, D.; Cremonese, G.; Da Deppo,
   V.; Debei, S.; De Cecco, M.; Fornasier, S.; Fulle, M.; Gicquel, A.;
   Groussin, O.; Gutiérrez, P. J.; Gutiérrez-Marqués, P.; Güttler,
   C.; Hviid, S. F.; Ip, W. -H.; Jorda, L.; Knollenberg, J.; Kovacs, G.;
   Kramm, J. -R.; Kührt, E.; Küppers, M.; La Forgia, F.; Lazzarin,
   M.; Lopez-Moreno, J. J.; Marzari, F.; Michalik, H.; Moissl-Fraund,
   R.; Moreno, F.; Mottola, S.; Naletto, G.; Oklay, N.; Preusker, F.;
   Scholten, F.; Shi, X.; Thomas, N.; Toth, I.; Tubiana, C.; Zitzmann, S.
2017A&A...608A.121H    Altcode:
  Context. The camera OSIRIS on board Rosetta obtained high-resolution
  images of the nucleus of comet 67P/Churyumov-Gerasimenko (67P). Great
  parts of the nucleus surface are composed of fractured terrain. <BR
  /> Aims: Fracture formation, evolution, and their potential
  relationship to physical processes that drive activity are not yet
  fully understood. Observed temperatures and gas production rates can
  be explained or interpreted with the presence of fractures by applying
  appropriate modelling methods. <BR /> Methods: We followed a transient
  thermophysical model approach that includes radiative, conductive, and
  water-ice sublimation fluxes by considering a variety of heliocentric
  distances, illumination conditions, and thermophysical properties
  for a set of characteristic fracture geometries on the nucleus of
  67P. We computed diurnal temperatures, heat fluxes, and outgassing
  behaviour in order to derive and distinguish the influence of the
  mentioned parameters on fractured terrain. <BR /> Results: Our analysis
  confirms that fractures, as already indicated by former studies about
  concavities, deviate from flat-terrain topographies with equivalent
  properties, mostly through the effect of self-heating. Compared to
  flat terrain, illuminated cometary fractures are generally warmer,
  with smaller diurnal temperature fluctuations. Maximum sublimation
  rates reach higher peaks, and dust mantle quenching effects on
  sublimation rates are weaker. Consequently, the rough structure
  of the fractured terrain leads to significantly higher inferred
  surface thermal inertia values than for flat areas with identical
  physical properties, which might explain the range of measured thermal
  inertia on 67P. <BR /> Conclusions: At 3.5 AU heliocentric distance,
  sublimation heat sinks in fractures converge to maximum values &gt;50
  W / m<SUP>2</SUP> and trigger dust activity that can be related mainly
  to H<SUB>2</SUB>O. Fractures are likely to grow through the erosive
  interplay of alternating sublimation and thermal fatigue.

---------------------------------------------------------
Title: Anomalous Surge of the White-Light Corona at the Onset of
    the Declining Phase of Solar Cycle 24
Authors: Lamy, P.
2017AGUFMSH13A2465L    Altcode:
  In late 2014, when the current solar cycle 24 was initiating its
  declining phase, the white-light corona as observed by the LASCO-C2
  coronagraph underwent an unexpected surge that increased its global
  radiance by 60%, reaching a peak value comparable to those of the
  more active solar cycle 23. The daily variations point to a localized
  enhancement or bulge in the electron density that persisted during
  several months. Carrington maps of the radiance and of the HMI
  photospheric field allow connecting this bulge to the emergence
  of the large sunspot complex AR 12192 in October 2014, the largest
  since AR 6368 observed in November 1990. The resulting unusually large
  increase of the magnetic field and the distortion of the neutral sheet
  in a characteristic inverse S-shape caused the coronal plasma to be
  trapped along a similar pattern. Three-dimensional reconstruction
  of the electron density based on time-dependent solar rotational
  tomography supplemented by 2D inversion of the coronal radiance
  confirms the morphology of the bulge and reveals that its level
  was well above the standard models of a corona of the maximum type,
  by typically a factor of 3. A rather satisfactory agreement is found
  with the results of the thermodynamic MHD model produced by Predictive
  Sciences although discrepancies are noted. The specific configuration
  of the magnetic field that led to the coronal surge resulted from the
  interplay of various factors prevailing at the onset of the declining
  phase of the solar cycles which was particularly efficient in the case
  of solar cycle 24.

---------------------------------------------------------
Title: ASPIICS: a giant, white light and emission line coronagraph
    for the ESA proba-3 formation flight mission
Authors: Lamy, P. L.; Vivès, S.; Curdt, W.; Damé, L.; Davila, J.;
   Defise, J. -M.; Fineschi, S.; Heinzel, P.; Howard, Russel; Kuzin,
   S.; Schmutz, W.; Tsinganos, K.; Zhukov, A.
2017SPIE10565E..0TL    Altcode:
  Classical externally-occulted coronagraphs are presently limited in
  their performances by the distance between the external occulter and
  the front objective. The diffraction fringe from the occulter and
  the vignetted pupil which degrades the spatial resolution prevent
  useful observations of the white light corona inside typically 2-2.5
  solar radii (Rsun). Formation flying offers and elegant solution to
  these limitations and allows conceiving giant, externally-occulted
  coronagraphs using a two-component space system with the external
  occulter on one spacecraft and the optical instrument on the
  other spacecraft at a distance of hundred meters [1, 2]. Such
  an instrument ASPIICS (Association de Satellites Pour l'Imagerie
  et l'Interférométrie de la Couronne Solaire) has been selected
  by the European Space Agency (ESA) to fly on its PROBA-3 mission
  of formation flying demonstration which is presently in phase B
  (Fig. 1). The classical design of an externally-occulted coronagraph is
  adapted to the formation flying configuration allowing the detection
  of the very inner corona as close as 0.04 solar radii from the solar
  limb. By tuning the position of the occulter spacecraft, it may even be
  possible to reach the chromosphere and the upper part of the spicules
  [3]. ASPIICS will perform (i) high spatial resolution imaging of the
  continuum K+F corona in photometric and polarimetric modes, (ii) high
  spatial resolution imaging of the E-corona in two coronal emission lines
  (CEL): Fe XIV and He I D3, and (iii) two-dimensional spectrophotometry
  of the Fe XIV emission line. ASPIICS will address the question of the
  coronal heating and the role of waves by characterizing propagating
  fluctuations (waves and turbulence) in the solar wind acceleration
  region and by looking for oscillations in the intensity and Doppler
  shift of spectral lines. The combined imaging and spectral diagnostics
  capabilities available with ASPIICS will allow mapping the velocity
  field of the corona both in the sky plane (directly on the images)
  and along the line-of-sight by measuring the Doppler shifts of
  emission lines in an effort to determine how the different components
  of the solar wind, slow and fast are accelerated. With a possible
  launch in 2014, ASPIICS will observe the corona during the maximum of
  solar activity, insuring the detection of many Coronal Mass Ejections
  (CMEs). By rapidly alternating high-resolution imaging and spectroscopy,
  CMEs will be thoroughly characterized.

---------------------------------------------------------
Title: ASPIICS/PROBA-3 formation flying solar coronagraph: Stray
    light analysis and optimization of the occulter
Authors: Landini, F.; Mazzoli, A.; Venet, M.; Vivès, S.; Romoli,
   M.; Lamy, P.; Massone, G.
2017SPIE10565E..1RL    Altcode:
  The "Association de Satellites Pour l'Imagerie et l'Interferometrie
  de la Couronne Solaire", ASPIICS, selected by ESA for the PROBA-3
  mission, heralds the next generation of coronagraph for solar research,
  exploiting formation flying to gain access to the inner corona under
  eclipse-like conditions for long periods of time. A detailed description
  of the ASPIICS instrument and of its scientific objectives can be
  found in [1]. ASPIICS is distributed on the two PROBA 3 spacecrafts
  (S/C) separated by 150 m. The coronagraph optical assembly is hosted
  by the "coronagraph S/C" protected from direct solar disk light by
  the occulting disk on the "occulter S/C". The most critical issue
  in the design of a solar coronagraph is the reduction of the stray
  light due to the diffraction and scattering of the solar disk light
  by the occulter, the aperture and the optics. In the present article,
  we deal with two of these issues: - The analysis of the stray light
  inside the telescope. - The optimization of the external occulter
  edge, in order to eliminate the Poisson spot behind the occulter and
  to lower the stray light level going through the entrance pupil of
  the telescope. This work was performed in the framework of the ESA
  STARTIGER program which took place at the Laboratoire d'Astrophysique
  de Marseille (LAM) during a 6-month period from September 2009 to March
  2010. In general, it is a very complicated task to combine the above
  two stray light issues together in the simulation and design phase
  as it requires to consider the propagation inside the telescope of
  the light diffracted by the external occulter. Actually, the present
  literature only reports diffraction calculations performed for simple
  occulting systems (i.e., two disks and serrated disk). A more pragmatic
  approach, also driven by the tight schedule of the STARTIGER program, is
  to separate the two contributions, and perform two different stray light
  analyses. This paper is dedicated to the description of both analyses:
  in particular, the first part is dedicated to the evaluation of the
  stray light inside the telescope, assuming a simple disk as occulter,
  and a preliminary baffle design is presented; the second part describes
  the investigation on the geometry of the external occulter, with a
  detailed description of the laboratory setup that has been designed
  and implemented to compare together several types of occulting systems.

---------------------------------------------------------
Title: METIS, the Multi Element Telescope for Imaging and
Spectroscopy: an instrument proposed for the solar orbiter mission
Authors: Antonucci, E.; Andretta, V.; Cesare, S.; Ciaravella, A.;
   Doschek, G.; Fineschi, S.; Giordano, S.; Lamy, P.; Moses, D.; Naletto,
   G.; Newmark, J.; Poletto, L.; Romoli, M.; Solanki, S.; Spadaro, D.;
   Teriaca, L.; Zangrilli, L.
2017SPIE10566E..0LA    Altcode:
  METIS, the Multi Element Telescope for Imaging and Spectroscopy,
  is an instrument proposed to the European Space Agency to be part of
  the payload of the Solar Orbiter mission. The instrument design has
  been conceived for performing extreme ultraviolet (EUV) spectroscopy
  both on the solar disk and off-limb, and near-Sun coronagraphy
  and spectroscopy. The proposed instrument suite consists of three
  different interconnected elements, COR, EUS and SOCS, sharing the
  same optical bench, electronics, and S/C heat shield aperture. COR is
  a visible-EUV multiband coronagraph based on a classical externally
  occulted design. EUS is the component of the METIS EUV disk spectrometer
  which includes the telescope and all the related mechanisms. Finally,
  SOCS is the METIS spectroscopic component including the dispersive
  system and the detectors. The capability of inserting a small telescope
  collecting coronal light has been added to perform also EUV coronal
  spectroscopy. METIS can simultaneously image the visible and ultraviolet
  emission of the solar corona and diagnose, with unprecedented temporal
  coverage and space resolution the structure and dynamics of the full
  corona in the range from 1.2 to 3.0 (1.6 to 4.1) solar radii (R⊙,
  measured from Sun centre) at minimum (maximum) perihelion during the
  nominal mission. It can also perform spectroscopic observations of the
  solar disk and out to 1.4 R⊙ within the 50-150 nm spectral region,
  and of the geo-effective coronal region 1.7-2.7 R⊙ within the 30-125
  nm spectral band.

---------------------------------------------------------
Title: Preliminary calibration results of the wide angle camera of
    the imaging instrument OSIRIS for the Rosetta mission
Authors: Da Deppo, V.; Naletto, G.; Nicolosi, P.; Zambolin, P.; De
   Cecco, M.; Debei, S.; Parzianello, G.; Ramous, P.; Zaccariotto, M.;
   Fornasier, S.; Verani, S.; Thomas, N.; Barthol, P.; Hviid, S. F.;
   Sebastian, I.; Meller, R.; Sierks, H.; Keller, H. U.; Barbieri, C.;
   Angrilli, F.; Lamy, P.; Rodrigo, R.; Rickman, H.; Wenzel, K. P.
2017SPIE10568E..0ND    Altcode:
  Rosetta is one of the cornerstone missions of the European Space Agency
  for having a rendezvous with the comet 67P/Churyumov-Gerasimenko in
  2014. The imaging instrument on board the satellite is OSIRIS (Optical,
  Spectroscopic and Infrared Remote Imaging System), a cooperation
  among several European institutes, which consists of two cameras:
  a Narrow (NAC) and a Wide Angle Camera (WAC). The WAC optical design
  is an innovative one: it adopts an all reflecting, unvignetted and
  unobstructed two mirror configuration which allows to cover a 12° ×
  12° field of view with an F/5.6 aperture and gives a nominal contrast
  ratio of about 10<SUP>-4</SUP>. The flight model of this camera has
  been successfully integrated and tested in our laboratories, and
  finally has been integrated on the satellite which is now waiting to
  be launched in February 2004. In this paper we are going to describe
  the optical characteristics of the camera, and to summarize the results
  so far obtained with the preliminary calibration data. The analysis of
  the optical performance of this model shows a good agreement between
  theoretical performance and experimental results.

---------------------------------------------------------
Title: Preliminary optical design of the coronagraph for the ASPIICS
    formation flying mission
Authors: Vivès, S.; Lamy, P.; Saisse, M.; Boit, J. -L.; Koutchmy, S.
2017SPIE10567E..1WV    Altcode:
  Formation flyers open new perspectives and allow to conceive
  giant, externally-occulted coronagraphs using a two-component space
  system with the external occulter on one spacecraft and the optical
  instrument on the other spacecraft at approximately 100-150 m from
  the first one. ASPIICS (Association de Satellites Pour l'Imagerie
  et l'Interfromtrie de la Couronne Solaire) is a mission proposed
  to ESA in the framework of the PROBA-3 program of formation flying
  which is presently in phase A to exploit this technique for coronal
  observations. ASPIICS is composed of a single coronagraph which performs
  high spatial resolution imaging of the corona as well as 2-dimensional
  spectroscopy of several emission lines from the coronal base out to
  3 R. The selected lines allow to address different coronal regions:
  the forbidden line of Fe XIV at 530.285 nm (coronal matter), Fe IX/X at
  637.4 nm (coronal holes), HeI at 587.6 nm (cold matter). An additional
  broad spectral channel will image the white light corona so as to derive
  electron densities. The classical design of an externally occulted
  coronagraph is adapted to the detection of the very inner corona as
  close as 1.01 R and the addition of a Fabry-Perot interferometer using
  a so-called "etalon". This paper is dedicated to the description of
  the optical design and its critical components: the entrance optics
  and the FabryPerot interferometer.

---------------------------------------------------------
Title: Stray light rejection in giant externally-occulted solar
coronagraphs: experimental developments
Authors: Venet, M.; Bazin, C.; Koutchmy, S.; Lamy, P.
2017SPIE10565E..1WV    Altcode:
  The advent of giant, formation-flight, externally-occulted solar
  coronagraphs such as ASPIICS (Association de Satellites Pour l'Imagerie
  et l'Interférométrie de la Couronne Solaire [1,2,3,4]) selected
  by the European Space Agency (ESA) for its third PROBA (Project for
  On-Board Autonomy) mission of formation flying demonstration (presently
  in phase B) and Hi-RISE proposed in the framework of ESA Cosmic Vision
  program, presents formidable challenges for the study and calibration of
  instrumental stray light. With distances between the external occulter
  (EO) and the optical pupil (OP) exceeding hundred meters and occulter
  sizes larger than a meter, it becomes impossible to perform tests at
  the real scale. The requirement to limit the over-occultation to less
  than 1.05 Rsun, orders of magnitude to what has been achieved so far in
  past coronagraphs, further adds to the challenge. We are approaching
  the problem experimentally using reduced scale simulators and present
  below a progress report of our work.

---------------------------------------------------------
Title: The global meter-level shape model of comet
    67P/Churyumov-Gerasimenko
Authors: Preusker, F.; Scholten, F.; Matz, K. -D.; Roatsch, T.;
   Hviid, S. F.; Mottola, S.; Knollenberg, J.; Kührt, E.; Pajola, M.;
   Oklay, N.; Vincent, J. -B.; Davidsson, B.; A'Hearn, M. F.; Agarwal,
   J.; Barbieri, C.; Barucci, M. A.; Bertaux, J. -L.; Bertini, I.;
   Cremonese, G.; Da Deppo, V.; Debei, S.; De Cecco, M.; Fornasier, S.;
   Fulle, M.; Groussin, O.; Gutiérrez, P. J.; Güttler, C.; Ip, W. -H.;
   Jorda, L.; Keller, H. U.; Koschny, D.; Kramm, J. R.; Küppers, M.;
   Lamy, P.; Lara, L. M.; Lazzarin, M.; Lopez Moreno, J. J.; Marzari,
   F.; Massironi, M.; Naletto, G.; Rickman, H.; Rodrigo, R.; Sierks,
   H.; Thomas, N.; Tubiana, C.
2017A&A...607L...1P    Altcode:
  We performed a stereo-photogrammetric (SPG) analysis of more than
  1500 Rosetta/OSIRIS NAC images of comet 67P/Churyumov-Gerasimenko
  (67P). The images with pixel scales in the range 0.2-3.0 m/pixel were
  acquired between August 2014 and February 2016. We finally derived
  a global high-resolution 3D description of 67P's surface, the SPG
  SHAP7 shape model. It consists of about 44 million facets (1-1.5 m
  horizontal sampling) and a typical vertical accuracy at the decimeter
  scale. Although some images were taken after perihelion, the SPG SHAP7
  shape model can be considered a pre-periheliondescription and replaces
  the previous SPG SHAP4S shape model. From the new shape model, some
  measures for 67P with very low 3σ uncertainties can be retrieved:
  18.56 km<SUP>3</SUP> ± 0.02 km<SUP>3</SUP> for the volume and 537.8
  kg/m<SUP>3</SUP> ± 0.7 kg/m<SUP>3</SUP> for the mean density assuming
  a mass value of 9.982 × 10<SUP>12</SUP> kg.

---------------------------------------------------------
Title: Three-dimensional views of the nucleus of Comet
67P/Churyumov-Gerasimenko: an atlas of stereo anaglyphs from
    OSIRIS-NAC images
Authors: Lamy, Philippe L.; Romeuf, David; Faury, Guillaume; Durand,
   Joelle; Beigbeder, Laurent; Groussin, Olivier
2017DPS....4941504L    Altcode:
  The Narrow Angle Camera (NAC) of the OSIRIS imaging system aboard
  ESA’s Rosetta spacecraft has acquired approximately 25000 images of
  the surface of the nucleus of comet 67P/Churyumov-Gerasimenko at various
  spatial scales down to centimeters per pixel. The bulk of these images
  have been obtained in sequences and the combined displacement of the
  Rosetta orbiter along its trajectory and the rotation of the nucleus
  allow associating many pairs of images appropriate to stereoscopic
  viewing. This is achieved by constructing anaglyphs after rotating the
  images so that the relative shift appears horizontal. The shift is set
  to limit the parallax to approximately 2° (with a maximum value of
  4°) for the foreground (to avoid image deformation) and the scene is
  placed behind the screen for optimal visual comfort. The rotation of the
  nucleus may have the adverse effect of introducing temporal incoherence,
  prominently from the variation of the cast shadows. Various solutions
  are implemented to circumvent this problem, usually by cropping the
  maximum extent of the shadows. A time of writing, approximately 900
  anaglyphs have been produced and we expect to reach several thousand
  once the systematic search of suitable pairs will be completed. We
  will present examples of anaglyphs. They will be searchable thanks
  to a dedicated data base that will document each one including its
  location on a 3D numerical model of the nucleus. Many possibilities of
  querying the parameters will be offered. It is anticipated that this
  atlas available online in the near future will be a valuable tool for
  fostering our understanding of the complex morphology of the cometary
  surface and of the processes at work , as well as offering spectacular
  stereoscopic views of the nucleus enjoyable by a general public.

---------------------------------------------------------
Title: Large scale morphological changes in the Hapi region on comet
    67P/Churyumov-Gerasimenko
Authors: Davidsson, Bjorn; Lee, Seungwon; von Allmen, Paul; Schloerb,
   Peter; Hofstadter, Mark; Sierks, Holger; Barbieri, Cesare; Gulkis,
   Samuel; Keller, Horst Uwe; Koschny, Detlef; Lamy, Philippe; Rickman,
   Hans; Rodrigo, Rafa; MIRO Team; OSIRIS Team
2017DPS....4941502D    Altcode:
  The Hapi region is located on the northern hemisphere of comet 67P/C-G
  at the neck that joins the two lobes of the nucleus. It primarily
  consists of granular material that is unresolved at 0.35 m/pixel
  resolution and that forms a smooth surface with small slopes with
  respect to local gravity. The OSIRIS cameras on the ESA spacecraft
  Rosetta observed Hapi regularly since its rendezvous with the comet
  in August 2014. No changes were seen during the first five months
  in orbit but on December 30, 2014, two spots appeared in Hapi. Over
  the course of two months they grew gradually into a 110 by 70 meter
  shallow depression with a depth of about 0.5 meters. We use OSIRIS
  observations to characterize the morphology and spectrophotometry of
  the region. We use measurements of the thermal emission of the comet by
  the MIRO millimeter and submillimeter radiometer in combination with
  thermophysical modeling to characterize the surface temperature, near
  surface temperature gradient, and thermal inertia of the region. The
  formation mechanism of the depression is discussed in view of these
  empirical data.

---------------------------------------------------------
Title: Evidences of Shear Deformations on Comet
67P/Churyumov-Gerasimenko: probing the internal structure of the
    nucleus
Authors: Matonti, C.; Attree, N.; Groussin, O.; Jorda, L.; Viseur,
   S.; Nebouy, D.; Auger, A. T.; Lamy, P.
2017EPSC...11..777M    Altcode:
  In this work we emphasize the occurrence of structures that can
  be explained by shear deformation on the nucleus of comet 67P. We
  first show that the majority of the lineaments in the neck regions
  correspond to fractures arranged in a network characteristic of shear
  deformation. These deformations are preferentially located in or near
  the neck regions. They have likely participated in the mechanical
  breakdown and the erosion of the nucleus. These results may have
  implication for deciphering the nucleus internal structural down to
  hundreds of meters and for inferring the nucleus material mechanical
  properties.

---------------------------------------------------------
Title: Characterization of the Abydos landing site of Philae on
    comet 67P/Churyumov-Gerasimenko
Authors: Lamy, P.; Faury, G.; Jorda, L.; Romeuf, D.; Capanna, C.;
   El-Maarry, M. R.; Gaskell, R.; Groussin, O.; Nebouy, D.
2017EPSC...11..560L    Altcode:
  Characterization of the final Abydos landing site of Philae on the
  nucleus of comet 67P/Churyumov-Gerasimenko based on twelve campaigns
  of imaging with the OSIRIS-NAC camera. The characterization is based
  on anaglyphs, a digital terrain model at a spatial scale of 40 cm
  and color maps. We present the regional setting of Abydos and define
  geological units. Abydos is essentially an alcove at the foot of a
  scarp composed of heavily fractured consolidated materials.

---------------------------------------------------------
Title: Seasonal erosion and restoration of the dust cover on comet
    67P/Churyumov-Gerasimenko as observed by OSIRIS onboard Rosetta
Authors: Hu, X.; Shi, X.; Sierks, H.; Fulle, M.; Blum, J.; Keller,
   H. U.; Kührt, E.; Davidsson, B.; Güttler, C.; Gundlach, B.; Pajola,
   M.; Bodewits, D.; Vincent, J. -B.; Oklay, N.; Massironi, M.; Fornasier,
   S.; Tubiana, C.; Groussin, O.; Boudreault, S.; Höfner, S.; Mottola,
   S.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.;
   A'Hearn, M.; Agarwal, J.; Barucci, M. A.; Bertaux, J. -L.; Bertini,
   I.; Cremonese, G.; Da Deppo, V.; Debei, S.; De Cecco, M.; Deller,
   J.; El-Maarry, M. R.; Gicquel, A.; Gutierrez-Marques, P.; Gutiérrez,
   P. J.; Hofmann, M.; Hviid, S. F.; Ip, W. -H.; Jorda, L.; Knollenberg,
   J.; Kovacs, G.; Kramm, J. -R.; Küppers, M.; Lara, L. M.; Lazzarin,
   M.; Lopez-Moreno, J. J.; Marzari, F.; Naletto, G.; Thomas, N.
2017A&A...604A.114H    Altcode:
  Context. Dust deposits or dust cover are a prevalent morphology in the
  northern hemi-nucleus of comet 67P/Churyumov-Gerasimenko (67P). The
  evolution of the dust deposits was captured by the OSIRIS camera system
  onboard the Rosetta spacecraft having escorted the comet for over two
  years. The observations shed light on the fundamental role of cometary
  activity in shaping and transforming the surface morphology. <BR />
  Aims: We aim to present OSIRIS observations of surface changes over
  the dust deposits before and after perihelion. The distribution of
  changes and a timeline of their occurrence are provided. We perform a
  data analysis to quantify the surface changes and investigate their
  correlation to water activity from the dust deposits. We further
  discuss how the results of our investigation are related to other
  findings from the Rosetta mission. <BR /> Methods: Surface changes
  were detected via systematic comparison of images, and quantified using
  shape-from-shading technique. Thermal models were applied to estimate
  the erosion of water ice in response to the increasing insolation over
  the areas where surface changes occurred. Modeling results were used
  for the interpretation of the observed surface changes. <BR /> Results:
  Surface changes discussed here were concentrated at mid-latitudes,
  between about 20°N and 40°N, marking a global transition from the
  dust-covered to rugged terrains. The changes were distributed in open
  areas exposed to ample solar illumination and likely subject to enhanced
  surface erosion before perihelion. The occurrence of changes followed
  the southward migration of the sub-solar point across the latitudes
  of their distribution. The erosion at locations of most changes was at
  least about 0.5 m, but most likely did not exceed several meters. The
  erosive features before perihelion had given way to a fresh, smooth
  cover of dust deposits after perihelion, suggesting that the dust
  deposits had been globally restored by at least about 1 m with ejecta
  from the intensely illuminated southern hemi-nucleus around perihelion,
  when the north was inactive during polar night. <BR /> Conclusions: The
  erosion and restoration of the northern dust deposits are morphological
  expressions of seasonality on 67P. Based on observations and thermal
  modeling results, it is inferred that the dust deposits contained a
  few percent of water ice in mass on average. Local inhomogeneity in
  water abundance at spatial scales below tens of meters is likely. We
  suspect that dust ejected from the deposits may not have escaped the
  comet in bulk. That is, at least half of the ejected mass was afloat
  in the inner-coma or/and redeposited over other areas of the nucleus.

---------------------------------------------------------
Title: Long-term monitoring of comet 67P/Churyumov-Gerasimenko's
    jets with OSIRIS onboard Rosetta
Authors: Schmitt, M. I.; Tubiana, C.; Güttler, C.; Sierks, H.;
   Vincent, J. -B.; El-Maarry, M. R.; Bodewits, D.; Mottola, S.;
   Fornasier, S.; Hofmann, M.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.;
   Koschny, D.; Rickman, H.; A'Hearn, M. F.; Agarwal, J.; Barucci, M. A.;
   Bertaux, J. -L.; Bertini, I.; Cremonese, G.; Da Deppo, V.; Davidsson,
   B.; Debei, S.; De Cecco, M.; Deller, J.; Fulle, M.; Gicquel, A.;
   Groussin, O.; Gutiérrez, P. J.; Hviid, S. F.; Ip, W. -H.; Jorda, L.;
   Keller, H. U.; Knollenberg, J.; Kramm, J. R.; Kührt, E.; Küppers,
   M.; Lara, L. M.; Lazzarin, M.; López-Moreno, J. J.; Marzari, F.;
   Naletto, G.; Oklay, N.; Pajola, M.; Prasanna, D.; Shi, X.; Scholten,
   F.; Toth, I.; Thomas, N.
2017MNRAS.469S.380S    Altcode:
  We used the OSIRIS camera system onboard the Rosetta spacecraft to
  monitor jet activity of comet 67P/Churyumov-Gerasimenko. With a monthly
  cadence, we covered an epoch from 2014 December to 2015 October,
  thereby including the first equinox and the perihelion passage. Jet
  features were measured in individual images, which were used to perform
  a statistical inversion. The study provides maps for the locations of
  likeliest sources of jet activity on the comet's surface as a function
  of time. The sources follow the subsolar latitude, show clustering
  and a broadening of the activity band with time in the Northern
  hemisphere. In the Southern hemisphere, they are not clustered but
  show a broader spread over all longitudes which is either related to
  the north-south dichotomy of the comet's topography or due to a higher
  insolation during southern summer.

---------------------------------------------------------
Title: Post-perihelion photometry of dust grains in the coma of
    67P Churyumov-Gerasimenko
Authors: Frattin, E.; Cremonese, G.; Simioni, E.; Bertini, I.;
   Lazzarin, M.; Ott, T.; Drolshagen, E.; La Forgia, F.; Sierks,
   H.; Barbieri, C.; Lamy, P.; Rodrigo, R.; Koschny, D.; Rickman, H.;
   Keller, H. U.; Agarwal, J.; A'Hearn, M. F.; Barucci, M. A.; Bertaux,
   J. -L.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.; Deller,
   J.; Ferrari, S.; Ferri, F.; Fornasier, S.; Fulle, M.; Gicquel, A.;
   Groussin, O.; Gutierrez, P. J.; Güttler, C.; Hofmann, M.; Hviid,
   S. F.; Ip, W. -H.; Jorda, L.; Knollenberg, J.; Kramm, J. -R.; Kührt,
   E.; Küppers, M.; Lara, L. M.; Lopez Moreno, J. J.; Lucchetti, A.;
   Marzari, F.; Massironi, M.; Mottola, S.; Naletto, G.; Oklay, N.;
   Pajola, M.; Penasa, L.; Shi, X.; Thomas, N.; Tubiana, C.; Vincent,
   J. -B.
2017MNRAS.469S.195F    Altcode:
  We present a photometric analysis of individual dust grains in the
  coma of comet 67P/Churyumov-Gerasimenko using OSIRIS images taken from
  2015 July to 2016 January. We analysed a sample of 555 taken during
  18 d at heliocentric distances ranging between 1.25 and 2.04 au and at
  nucleocentric distances between 80 and 437 km. An automated method to
  detect the tracks was specifically developed. The images were taken
  by OSIRIS NAC in four different filters: Near-IR (882 nm), Orange
  (649 nm), FarOrange (649 nm) and Blue (480 nm). It was not always
  possible to recognize all the grains in the four filters, hence we
  measured the spectral slope in two wavelengths ranges: in the interval
  [480-649] nm, for 1179 grains, and in the interval [649-882] nm, for
  746 grains. We studied the evolution of the two populations' average
  spectral slopes. The data result scattered around the average value in
  the range [480-649] nm, while in the [649-882] nm we observe a slight
  decreasing moving away from the Sun as well as a slight increasing with
  the nucleocentric distance. A spectrophotometric analysis was performed
  on a subsample of 339 grains. Three major groups were defined, based
  on the spectral slope between [535-882] nm: (I) the steep spectra
  that may be related with organic material, (II) the spectra with an
  intermediate slope, likely a mixture of silicates and organics and (III)
  flat spectra that may be associated with a high abundance of water ice.

---------------------------------------------------------
Title: Characterization of dust aggregates in the vicinity of the
    Rosetta spacecraft
Authors: Güttler, C.; Hasselmann, P. H.; Li, Y.; Fulle, M.; Tubiana,
   C.; Kovacs, G.; Agarwal, J.; Sierks, H.; Fornasier, S.; Hofmann,
   M.; Gutiérrez Marqués, P.; Ott, T.; Drolshagen, E.; Bertini,
   I.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman,
   H.; A'Hearn, M. F.; Barucci, M. A.; Bodewits, D.; Bertaux, J. -L.;
   Boudreault, S.; Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.;
   De Cecco, M.; Deller, J.; Geiger, B.; Groussin, O.; Gutiérrez, P. J.;
   Hviid, S. F.; Ip, W. -H.; Jorda, L.; Keller, H. U.; Knollenberg, J.;
   Kramm, J. R.; Kührt, E.; Küppers, M.; Lara, L. M.; Lazzarin, M.;
   López-Moreno, J. J.; Marzari, F.; Mottola, S.; Naletto, G.; Oklay,
   N.; Pajola, M.; Shi, X.; Thomas, N.; Vincent, J. -B.
2017MNRAS.469S.312G    Altcode:
  In a Rosetta/OSIRIS imaging activity in 2015 June, we have observed the
  dynamic motion of particles close to the spacecraft. Due to the focal
  setting of the OSIRIS wide angle camera, these particles were blurred,
  which can be used to measure their distances to the spacecraft. We
  detected 109 dust aggregates over a 130 min long sequence, and find
  that their sizes are around a millimetre and their distances cluster
  between 2 and 40 m from the spacecraft. Their number densities are
  about a factor 10 higher than expected for the overall coma and highly
  fluctuating. Their velocities are small compared to the spacecraft
  orbital motion and directed away from the spacecraft, towards the
  comet. From this we conclude that they have interacted with the
  spacecraft and assess three possible scenarios. In the likeliest
  of the three scenarios, centimetre-sized aggregates collide with the
  spacecraft and we would observe the fragments. Ablation of a dust layer
  on the spacecraft's z panel (remote instrument viewing direction)
  when rotated towards the Sun is a reasonable alternative. We could
  also measure an acceleration for a subset of 18 aggregates, which
  is directed away from the Sun and can be explain by a rocket effect,
  which requires a minimum ice fraction of the order of 0.1 per cent.

---------------------------------------------------------
Title: Evidence of sub-surface energy storage in comet 67P from the
    outburst of 2016 July 03
Authors: Agarwal, J.; Della Corte, V.; Feldman, P. D.; Geiger,
   B.; Merouane, S.; Bertini, I.; Bodewits, D.; Fornasier, S.; Grün,
   E.; Hasselmann, P.; Hilchenbach, M.; Höfner, S.; Ivanovski, S.;
   Kolokolova, L.; Pajola, M.; Rotundi, A.; Sierks, H.; Steffl, A. J.;
   Thomas, N.; A'Hearn, M. F.; Barbieri, C.; Barucci, M. A.; Bertaux,
   J. -L.; Boudreault, S.; Cremonese, G.; Da Deppo, V.; Davidsson,
   B.; Debei, S.; De Cecco, M.; Deller, J. F.; Feaga, L. M.; Fischer,
   H.; Fulle, M.; Gicquel, A.; Groussin, O.; Güttler, C.; Gutiérrez,
   P. J.; Hofmann, M.; Hornung, K.; Hviid, S. F.; Ip, W. -H.; Jorda, L.;
   Keller, H. U.; Kissel, J.; Knollenberg, J.; Koch, A.; Koschny, D.;
   Kramm, J. -R.; Kührt, E.; Küppers, M.; Lamy, P. L.; Langevin, Y.;
   Lara, L. M.; Lazzarin, M.; Lin, Z. -Y.; Lopez Moreno, J. J.; Lowry,
   S. C.; Marzari, F.; Mottola, S.; Naletto, G.; Oklay, N.; Parker,
   J. Wm.; Rodrigo, R.; Rynö, J.; Shi, X.; Stenzel, O.; Tubiana, C.;
   Vincent, J. -B.; Weaver, H. A.; Zaprudin, B.
2017MNRAS.469S.606A    Altcode: 2017arXiv171010235A
  On 2016 July 03, several instruments onboard ESA's Rosetta spacecraft
  detected signs of an outburst event on comet 67P, at a heliocentric
  distance of 3.32 au from the Sun, outbound from perihelion. We here
  report on the inferred properties of the ejected dust and the surface
  change at the site of the outburst. The activity coincided with the
  local sunrise and continued over a time interval of 14-68 min. It
  left a 10-m-sized icy patch on the surface. The ejected material
  comprised refractory grains of several hundred microns in size, and
  sub-micron-sized water ice grains. The high dust mass production rate
  is incompatible with the free sublimation of crystalline water ice
  under solar illumination as the only acceleration process. Additional
  energy stored near the surface must have increased the gas density. We
  suggest a pressurized sub-surface gas reservoir, or the crystallization
  of amorphous water ice as possible causes.

---------------------------------------------------------
Title: Seasonal mass transfer on the nucleus of comet
    67P/Chuyumov-Gerasimenko
Authors: Keller, H. U.; Mottola, S.; Hviid, S. F.; Agarwal, J.;
   Kührt, E.; Skorov, Y.; Otto, K.; Vincent, J. -B.; Oklay, N.;
   Schröder, S. E.; Davidsson, B.; Pajola, M.; Shi, X.; Bodewits,
   D.; Toth, I.; Preusker, F.; Scholten, F.; Sierks, H.; Barbieri,
   C.; Lamy, P.; Rodrigo, R.; Koschny, D.; Rickman, H.; A'Hearn, M. F.;
   Barucci, M. A.; Bertaux, J. -L.; Bertini, I.; Cremonese, G.; Da Deppo,
   V.; Debei, S.; De Cecco, M.; Deller, J.; Fornasier, S.; Fulle, M.;
   Groussin, O.; Gutiérrez, P. J.; Güttler, C.; Hofmann, M.; Ip, W. -H.;
   Jorda, L.; Knollenberg, J.; Kramm, J. R.; Küppers, M.; Lara, L. -M.;
   Lazzarin, M.; Lopez-Moreno, J. J.; Marzari, F.; Naletto, G.; Tubiana,
   C.; Thomas, N.
2017MNRAS.469S.357K    Altcode: 2017arXiv170706812K
  We collect observational evidence that supports the scheme of mass
  transfer on the nucleus of comet 67P/Churyumov-Gerasimenko. The
  obliquity of the rotation axis of 67P causes strong seasonal
  variations. During perihelion the southern hemisphere is four times
  more active than the north. Northern territories are widely covered
  by granular material that indicates back fall originating from the
  active south. Decimetre sized chunks contain water ice and their
  trajectories are influenced by an antisolar force instigated by
  sublimation. OSIRIS observations suggest that up to 20 per cent of
  the particles directly return to the nucleus surface taking several
  hours of traveltime. The back fall covered northern areas are active if
  illuminated but produce mainly water vapour. The decimetre chunks from
  the nucleus surface are too small to contain more volatile compounds
  such as CO<SUB>2</SUB> or CO. This causes a north-south dichotomy of
  the composition measurements in the coma. Active particles are trapped
  in the gravitational minimum of Hapi during northern winter. They are
  `shock frozen' and only re-activated when the comet approaches the
  sun after its aphelion passage. The insolation of the big cavity is
  enhanced by self-heating, I.e. reflection and IR radiation from the
  walls. This, together with the pristinity of the active back fall,
  explains the early observed activity of the Hapi region. Sobek may
  be a role model for the consolidated bottom of Hapi. Mass transfer in
  the case of 67P strongly influences the evolution of the nucleus and
  the interpretation of coma measurements.

---------------------------------------------------------
Title: Investigating the physical properties of outbursts on comet
    67P/Churyumov-Gerasimenko
Authors: Lin, Zhong-Yi; Knollenberg, J.; Vincent, J. -B.; A'Hearn,
   M. F.; Ip, W. -H.; Sierks, H.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.;
   Koschny, D.; Rickman, H.; Keller, H. U.; Mottola, S.; Bodewits, D.;
   Agarwal, J.; Barucci, M. A.; Bertaux, J. -L.; Bertini, I.; Cremonese,
   G.; Deller, J.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.;
   Fornasier, S.; Fulle, M.; Groussin, O.; Gutiérrez, P. J.; Güttler,
   C.; Hofmann, M.; Hviid, S. F.; Jorda, L.; Kovacs, G.; Kramm, J. -R.;
   Kührt, E.; Küppers, M.; Lai, I. -L.; Lara, L. M.; Lazzarin, M.;
   Lee, J. -C.; López-Moreno, J. J.; Marzari, F.; Naletto, G.; Oklay,
   N.; Ott, T.; Drolshagen, E.; Shi, X.; Thomas, N.; Tubiana, C.
2017MNRAS.469S.731L    Altcode:
  Cometary outbursts on several comets have been observed
  both by ground-based telescopes and by in situ instruments on
  spacecraft. However, the mechanism behind these phenomena and their
  physical properties are still unclear. The optical, spectrocopic
  and infrared remote imaging system (OSIRIS) onboard the Rosetta
  spacecraft provided first-hand information on the outbursts from comet
  67P/Churyumov-Gerasimenko during its perihelion passage in 2015. The
  physical properties of the outbursts can be investigated by examining
  the time series of these high-resolution images. An analysis is made
  of the wide- and narrow-angle images obtained during the monitoring
  of the outburst sequences, which occurred between July and September
  in 2015. A ring-masking technique is used to calculate the excess
  brightness of the outbursts. The ejected mass and expansion velocity
  of the outbursts is estimated from differences in images made with the
  same filter (orange filter). The calculated excess brightness from
  these outburst plumes ranges from a few per cent to 28 per cent. In
  some major outbursts, the brightness contribution from the outburst
  plume can be one or two times higher than that of the typical coma jet
  activities. The strongest event was the perihelion outburst detected
  just a few hours before perihelion. The mass ejection rate during a
  generic outburst could reach a few per cent of the steady-state value of
  the dust coma. Transient events are detected by studying the brightness
  slope of the outburst plume with continuous streams of outflowing
  gas and dust triggered by driving mechanisms, as yet not understood,
  which remain active for several minutes to less than a few hours.

---------------------------------------------------------
Title: Modelling of the outburst on 2015 July 29 observed with OSIRIS
    cameras in the Southern hemisphere of comet 67P/Churyumov-Gerasimenko
Authors: Gicquel, A.; Rose, M.; Vincent, J. -B.; Davidsson, B.;
   Bodewits, D.; A'Hearn, M. F.; Agarwal, J.; Fougere, N.; Sierks, H.;
   Bertini, I.; Lin, Z. -Y.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.;
   Koschny, D.; Rickman, H.; Keller, H. U.; Barucci, M. A.; Bertaux,
   J. -L.; Besse, S.; Boudreault, S.; Cremonese, G.; Da Deppo, V.; Debei,
   S.; Deller, J.; De Cecco, M.; Frattin, E.; El-Maarry, M. R.; Fornasier,
   S.; Fulle, M.; Groussin, O.; Gutiérrez, P. J.; Gutiérrez-Marquez,
   P.; Güttler, C.; Höfner, S.; Hofmann, M.; Hu, X.; Hviid, S. F.; Ip,
   W. -H.; Jorda, L.; Knollenberg, J.; Kovacs, G.; Kramm, J. -R.; Kührt,
   E.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Moreno, J. J. Lopez;
   Lowry, S.; Marzari, F.; Masoumzadeh, N.; Massironi, M.; Moreno,
   F.; Mottola, S.; Naletto, G.; Oklay, N.; Pajola, M.; Preusker, F.;
   Scholten, F.; Shi, X.; Thomas, N.; Toth, I.; Tubiana, C.
2017MNRAS.469S.178G    Altcode: 2017arXiv170602729G
  Images of the nucleus and the coma (gas and dust) of comet
  67P/Churyumov- Gerasimenko have been acquired by the OSIRIS (Optical,
  Spectroscopic and Infrared Remote Imaging System) cameras since 2014
  March using both the wide-angle camera and the narrow-angle camera
  (NAC). We use images from the NAC camera to study a bright outburst
  observed in the Southern hemisphere on 2015 July 29. The high spatial
  resolution of the NAC is needed to localize the source point of the
  outburst on the surface of the nucleus. The heliocentric distance is
  1.25 au and the spacecraft-comet distance is 186 km. Aiming to better
  understand the physics that led to the outgassing, we used the Direct
  Simulation Monte Carlo method to study the gas flow close to the nucleus
  and the dust trajectories. The goal is to understand the mechanisms
  producing the outburst. We reproduce the opening angle of the outburst
  in the model and constrain the outgassing ratio between the outburst
  source and the local region. The outburst is in fact a combination
  of both gas and dust, in which the active surface is approximately
  10 times more active than the average rate found in the surrounding
  areas. We need a number of dust particles 7.83 × 10<SUP>11</SUP> to
  6.90 × 10<SUP>15</SUP> (radius 1.97-185 μm), which correspond to a
  mass of dust (220-21) × 10<SUP>3</SUP> kg.

---------------------------------------------------------
Title: The scattering phase function of comet
    67P/Churyumov-Gerasimenko coma as seen from the Rosetta/OSIRIS
    instrument
Authors: Bertini, I.; La Forgia, F.; Tubiana, C.; Güttler, C.; Fulle,
   M.; Moreno, F.; Frattin, E.; Kovacs, G.; Pajola, M.; Sierks, H.;
   Barbieri, C.; Lamy, P.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller,
   H. U.; Agarwal, J.; A'Hearn, M. F.; Barucci, M. A.; Bertaux, J. -L.;
   Bodewits, D.; Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.;
   De Cecco, M.; Drolshagen, E.; Ferrari, S.; Ferri, F.; Fornasier, S.;
   Gicquel, A.; Groussin, O.; Gutierrez, P. J.; Hasselmann, P. H.; Hviid,
   S. F.; Ip, W. -H.; Jorda, L.; Knollenberg, J.; Kramm, J. R.; Kührt,
   E.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Lin, Z. -Y.; Moreno,
   J. J. Lopez; Lucchetti, A.; Marzari, F.; Massironi, M.; Mottola, S.;
   Naletto, G.; Oklay, N.; Ott, T.; Penasa, L.; Thomas, N.; Vincent,
   J. -B.
2017MNRAS.469S.404B    Altcode:
  The study of dust, the most abundant material in cometary nuclei,
  is pivotal in understanding the original materials forming the
  Solar system. Measuring the coma phase function provides a tool to
  investigate the nature of cometary dust. Rosetta/OSIRIS sampled the
  coma phase function of comet 67P/Churyumov-Gerasimenko, covering
  a large phase angle range in a small amount of time. Twelve series
  were acquired in the period from 2015 March to 2016 February for this
  scientific purpose. These data allowed, after stray light removal,
  measuring the phase function shape, its reddening, and phase reddening
  while varying heliocentric and nucleocentric distances. Despite small
  dissimilarities within different series, we found a constant overall
  shape. The reflectance has a u-shape with minimum at intermediate
  phase angles, reaching similar values at the smallest and largest
  phase angle sampled. The comparison with cometary phase functions in
  literature indicates OSIRIS curves being consistent with the ones
  found in many other single comets. The dust has a negligible phase
  reddening at α &lt; 90°, indicating a coma dominated by single
  scattering. We measured a reddening of [11-14] %/100 nm between 376
  and 744 nm. No trend with heliocentric or nucleocentric distance was
  found, indicating the coma doesn't change its spectrum with time. These
  results are consistent with single coma grains and close-nucleus coma
  photometric results. Comparison with nucleus photometry indicates a
  different backscattering phase function shape and similar reddening
  values only at α &lt; 30°. At larger phase angles, the nucleus
  becomes significantly redder than the coma.

---------------------------------------------------------
Title: Constraints on cometary surface evolution derived from a
    statistical analysis of 67P's topography
Authors: Vincent, J. -B.; Hviid, S. F.; Mottola, S.; Kuehrt, E.;
   Preusker, F.; Scholten, F.; Keller, H. U.; Oklay, N.; de Niem, D.;
   Davidsson, B.; Fulle, M.; Pajola, M.; Hofmann, M.; Hu, X.; Rickman,
   H.; Lin, Z. -Y.; Feller, C.; Gicquel, A.; Boudreault, S.; Sierks, H.;
   Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; A'Hearn, M. F.;
   Barucci, M. A.; Bertaux, J. -L.; Bertini, I.; Cremonese, G.; Da Deppo,
   V.; Debei, S.; De Cecco, M.; Deller, J.; Fornasier, S.; Groussin, O.;
   Gutiérrez, P. J.; Gutiérrez-Marquez, P.; Güttler, C.; Ip, W. -H.;
   Jorda, L.; Knollenberg, J.; Kovacs, G.; Kramm, J. -R.; Küppers, M.;
   Lara, L. M.; Lazzarin, M.; Lopez Moreno, J. J.; Marzari, F.; Naletto,
   G.; Penasa, L.; Shi, X.; Thomas, N.; Toth, I.; Tubiana, C.
2017MNRAS.469S.329V    Altcode: 2017arXiv170700734V
  We present a statistical analysis of the distribution of large-scale
  topographic features on comet 67P/Churyumov-Gerasimenko. We observe that
  the cumulative cliff height distribution across the surface follows a
  power law with a slope equal to -1.69 ± 0.02. When this distribution
  is studied independently for each region, we find a good correlation
  between the slope of the power law and the orbital erosion rate of the
  surface. For instance, the Northern hemisphere topography is dominated
  by structures on the 100 m scale, while the Southern hemisphere
  topography, illuminated at perihelion, is dominated by 10 m scale
  terrain features. Our study suggests that the current size of a cliff
  is controlled not only by material cohesion but also by the dominant
  erosional process in each region. This observation can be generalized
  to other comets, where we argue that primitive nuclei are characterized
  by the presence of large cliffs with a cumulative height-power index
  equal to or above -1.5, while older, eroded cometary surfaces have a
  power index equal to or below -2.3. In effect, our model shows that
  a measure of the topography provides a quantitative assessment of a
  comet's erosional history, that is, its evolutionary age.

---------------------------------------------------------
Title: The pebbles/boulders size distributions on Sais: Rosetta's
    final landing site on comet 67P/Churyumov-Gerasimenko
Authors: Pajola, M.; Lucchetti, A.; Fulle, M.; Mottola, S.; Hamm, M.;
   Da Deppo, V.; Penasa, L.; Kovacs, G.; Massironi, M.; Shi, X.; Tubiana,
   C.; Güttler, C.; Oklay, N.; Vincent, J. B.; Toth, I.; Davidsson,
   B.; Naletto, G.; Sierks, H.; Barbieri, C.; Lamy, P. L.; Rodrigo,
   R.; Koschny, D.; Rickman, H.; Keller, H. U.; Agarwal, J.; A'Hearn,
   M. F.; Barucci, M. A.; Bertaux, J. L.; Bertini, I.; Cremonese, G.;
   Debei, S.; De Cecco, M.; Deller, J.; El Maarry, M. R.; Fornasier, S.;
   Frattin, E.; Gicquel, A.; Groussin, O.; Gutierrez, P. J.; Höfner,
   S.; Hofmann, M.; Hviid, S. F.; Ip, W. H.; Jorda, L.; Knollenberg,
   J.; Kramm, J. R.; Kührt, E.; Küppers, M.; Lara, L. M.; Lazzarin,
   M.; Moreno, J. J. Lopez; Marzari, F.; Michalik, H.; Preusker, F.;
   Scholten, F.; Thomas, N.
2017MNRAS.469S.636P    Altcode: 2017MNRAS.471..680P
  By using the imagery acquired by the Optical, Spectroscopic, and
  Infrared Remote Imaging System Wide-Angle Camera (OSIRIS WAC), we
  prepare a high-resolution morphological map of the Rosetta Sais final
  landing site, characterized by an outcropping consolidated terrain
  unit, a coarse boulder deposit and a fine particle deposit. Thanks
  to the 0.014 m resolution images, we derive the pebbles/boulders
  size-frequency distribution (SFD) of the area in the size range of
  0.07-0.70 m. Sais' SFD is best fitted with a two-segment differential
  power law: the first segment is in the range 0.07-0.26 m, with an index
  of -1.7 ± 0.1, while the second is in the range 0.26-0.50 m, with
  an index of -4.2 +0.4/-0.8. The `knee' of the SFD, located at 0.26 m,
  is evident both in the coarse and fine deposits. When compared to the
  Agilkia Rosetta Lander Imaging System images, Sais surface is almost
  entirely free of the ubiquitous, cm-sized debris blanket observed
  by Philae. None the less, a similar SFD behaviour of Agilkia, with a
  steeper distribution above ∼0.3 m, and a flatter trend below that,
  is observed. The activity evolution of 67P along its orbit provides
  a coherent scenario of how these deposits were formed. Indeed,
  different lift pressure values occurring on the two locations and at
  different heliocentric distances explain the presence of the cm-sized
  debris blanket on Agilkia observed at 3.0 au inbound. Contrarily, Sais
  activity after 2.1 au outbound has almost completely eroded the fine
  deposits fallen during perihelion, resulting in an almost dust-free
  surface observed at 3.8 au.

---------------------------------------------------------
Title: The opposition effect of 67P/Churyumov-Gerasimenko on
    post-perihelion Rosetta images
Authors: Hasselmann, P. H.; Barucci, M. A.; Fornasier, S.; Feller, C.;
   Deshapriya, J. D. P.; Fulchignoni, M.; Jost, B.; Sierks, H.; Barbieri,
   C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; A'Hearn, M.;
   Bertaux, J. -L.; Bertini, I.; Cremonese, G.; Da Deppo, V.; Davidsson,
   B.; Debei, S.; De Cecco, M.; Deller, J.; Fulle, M.; Gaskell, R. W.;
   Groussin, O.; Gutierrez, P. J.; Güttler, C.; Hofmann, M.; Hviid,
   S. F.; Ip, W. -H.; Jorda, L.; Keller, H. U.; Knollenberg, J.; Kovacs,
   G.; Kramm, R.; Kührt, E.; Küppers, M.; Lara, M. L.; Lazzarin, M.;
   Lopez-Moreno, J. J.; Marzari, F.; Mottola, S.; Naletto, G.; Oklay,
   N.; Pommerol, A.; Thomas, N.; Tubiana, C.; Vincent, J. -B.
2017MNRAS.469S.550H    Altcode:
  High-resolution OSIRIS/Rosetta images of 67P/Churyumov-Gerasimenko
  acquired on the night run of 2016 April 9-10 show, at large scale,
  an opposition effect (OE) spot sweeping across Imhotep as the phase
  angle ranges from 0° to 17°. In this work, we fitted the phase curve
  of the whole surface imaged as well as three particular features using
  both the linear-exponential and Hapke models. These features encompass
  different types of spectral behaviour: a circular mesa, one venous
  structure and an assemblage of bright spots, going from red to blue
  colours. Both the Hapke and linear-exponential parameters indicate a
  stepwise sharpening of the OE from bright spots to circular mesa. Yet
  a very broad nonlinear phase curve is verified and no sign of sharp OE
  associated with a coherent-backscattering mechanism is observed. We
  estimate that the 67P surface is dominated by opaque, desiccated and
  larger-than-wavelength irregular grains. Veins and bright spots display
  photometric properties consistent with surfaces becoming slightly
  brighter as they are enriched by high-albedo ice grains. We also report
  the estimation of normal albedo for all cometary regions observed
  throughout the image sequence. Comparison to pre-perihelion results
  indicates that far better insolation of northern brighter regions,
  I.e. Hapi, Hathor and Seth, is sufficient to explain mismatches on the
  photometric parameters. However, metre-scale photometric analysis of
  the Imhotep-Ash boundary area advocates for mild darkening (&lt;7 per
  cent) of the surface at local scale.

---------------------------------------------------------
Title: The highly active Anhur-Bes regions in the
67P/Churyumov-Gerasimenko comet: results from OSIRIS/ROSETTA
    observations
Authors: Fornasier, S.; Feller, C.; Lee, J. -C.; Ferrari, S.;
   Massironi, M.; Hasselmann, P. H.; Deshapriya, J. D. P.; Barucci,
   M. A.; El-Maarry, M. R.; Giacomini, L.; Mottola, S.; Keller, H. U.;
   Ip, W. -H.; Lin, Z. -Y.; Sierks, H.; Barbieri, C.; Lamy, P. L.;
   Rodrigo, R.; Koschny, D.; Rickman, H.; Agarwal, J.; A'Hearn, M.;
   Bertaux, J. -L.; Bertini, I.; Cremonese, G.; Da Deppo, V.; Davidsson,
   B.; Debei, S.; De Cecco, M.; Deller, J.; Fulle, M.; Groussin, O.;
   Gutierrez, P. J.; Güttler, C.; Hofmann, M.; Hviid, S. F.; Jorda,
   L.; Knollenberg, J.; Kovacs, G.; Kramm, R.; Kührt, E.; Küppers, M.;
   Lara, M. L.; Lazzarin, M.; Lopez Moreno, J. J.; Marzari, F.; Naletto,
   G.; Oklay, N.; Pajola, M.; Shi, X.; Thomas, N.; Toth, I.; Tubiana,
   C.; Vincent, J. -B.
2017MNRAS.469S..93F    Altcode: 2017arXiv170702945F
  The Southern hemisphere of the 67P/Churyumov-Gerasimenko comet has
  become visible from Rosetta only since 2015 March. It was illuminated
  during the perihelion passage and therefore it contains the regions
  that experienced the strongest heating and erosion rates, thus exposing
  the sub-surface most pristine material. In this work we investigate,
  thanks to the OSIRIS images, the geomorphology, the spectrophotometry
  and some transient events of two Southern hemisphere regions: Anhur
  and part of Bes. Bes is dominated by outcropping consolidated terrain
  covered with fine particle deposits, while Anhur appears strongly eroded
  with elongated canyon-like structures, scarp retreats, different kinds
  of deposits and degraded sequences of strata indicating a pervasive
  layering. We discovered a new 140 m long and 10 m high scarp formed
  in the Anhur-Bes boundary during/after the perihelion passage, close
  to the area where exposed CO<SUB>2</SUB> and H<SUB>2</SUB>O ices were
  previously detected. Several jets have been observed originating from
  these regions, including the strong perihelion outburst, an active
  pit and a faint optically thick dust plume. We identify several areas
  with a relatively bluer slope (i.e. a lower spectral slope value) than
  their surroundings, indicating a surface composition enriched with
  some water ice. These spectrally bluer areas are observed especially
  in talus and gravitational accumulation deposits where freshly exposed
  material had fallen from nearby scarps and cliffs. The investigated
  regions become spectrally redder beyond 2 au outbound when the dust
  mantle became thicker, masking the underlying ice-rich layers.

---------------------------------------------------------
Title: Long-term survival of surface water ice on comet 67P
Authors: Oklay, N.; Mottola, S.; Vincent, J. -B.; Pajola, M.;
   Fornasier, S.; Hviid, S. F.; Kappel, D.; Kührt, E.; Keller, H. U.;
   Barucci, M. A.; Feller, C.; Preusker, F.; Scholten, F.; Hall, I.;
   Sierks, H.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.;
   Rickman, H.; A'Hearn, M. F.; Bertaux, J. -L.; Bertini, I.; Bodewits,
   D.; Cremonese, G.; Da Deppo, V.; Davidsson, B. J. R.; Debei, S.; De
   Cecco, M.; Deller, J.; Deshapriya, J. D. P.; Fulle, M.; Gicquel, A.;
   Groussin, O.; Gutiérrez, P. J.; Güttler, C.; Hasselmann, P. H.;
   Hofmann, M.; Ip, W. -H.; Jorda, L.; Knollenberg, J.; Kovacs, G.;
   Kramm, J. -R.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Lin, Z. -Y.;
   Moreno, J. J. Lopez; Lucchetti, A.; Marzari, F.; Masoumzadeh, N.;
   Naletto, G.; Pommerol, A.; Shi, X.; Thomas, N.; Tubiana, C.
2017MNRAS.469S.582O    Altcode:
  Numerous water-ice-rich deposits surviving more than several months
  on comet 67P/Churyumov-Gerasimenko were observed during the Rosetta
  mission. We announce the first-time detection of water-ice features
  surviving up to 2 yr since their first observation via OSIRIS (Optical,
  Spectroscopic, and Infrared Remote Imaging System) NAC (narrow angle
  camera). Their existence on the nucleus of comet 67P at the arrival of
  the Rosetta spacecraft suggests that they were exposed to the surface
  during the comet's previous orbit. We investigated the temporal
  variation of large water-ice patches to understand the long-term
  sustainability of water ice on cometary nuclei on time-scales of
  months and years. Large clusters are stable over typical periods
  of 0.5 yr and reduce their size significantly around the comet's
  perihelion passage, while small exposures disappear. We characterized
  the temporal variation of their multispectral signatures. In large
  clusters, dust jets were detected, whereas in large isolated ones no
  associated activity was detected. Our thermal analysis shows that the
  long-term sustainability of water-ice-rich features can be explained by
  the scarce energy input available at their locations over the first half
  year. However, the situation reverses for the period lasting several
  months around perihelion passage. Our two end-member mixing analysis
  estimates a pure water-ice equivalent thickness up to 15 cm within one
  isolated patch, and up to 2 m for the one still observable through the
  end of the mission. Our spectral modelling estimates up to 48 per cent
  water-ice content for one of the large isolated feature, and up to 25
  per cent water ice on the large boulders located within clusters.

---------------------------------------------------------
Title: A three-dimensional modelling of the layered structure of
    comet 67P/Churyumov-Gerasimenko
Authors: Penasa, L.; Massironi, M.; Naletto, G.; Simioni, E.; Ferrari,
   S.; Pajola, M.; Lucchetti, A.; Preusker, F.; Scholten, F.; Jorda,
   L.; Gaskell, R.; Ferri, F.; Marzari, F.; Davidsson, B.; Mottola,
   S.; Sierks, H.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny,
   D.; Rickman, H.; Keller, H. U.; Agarwal, J.; A'Hearn, M. F.; Barucci,
   M. A.; Bertaux, J. L.; Bertini, I.; Cremonese, G.; Da Deppo, V.; Debei,
   S.; De Cecco, M.; Deller, J.; Feller, C.; Fornasier, S.; Frattin, E.;
   Fulle, M.; Groussin, O.; Gutierrez, P. J.; Güttler, C.; Hofmann, M.;
   Hviid, S. F.; Ip, W. H.; Knollenberg, J.; Kramm, J. R.; Kührt, E.;
   Küppers, M.; La Forgia, F.; Lara, L. M.; Lazzarin, M.; Lee, J. -C.;
   Lopez Moreno, J. J.; Oklay, N.; Shi, X.; Thomas, N.; Tubiana, C.;
   Vincent, J. B.
2017MNRAS.469S.741P    Altcode:
  We provide a three-dimensional model of the inner layered structure of
  comet 67P based on the hypothesis of an extended layering independently
  wrapping each lobe. A large set of terrace orientations was collected
  on the latest shape model and then used as a proxy for the local
  orientation of the surfaces of discontinuity which defines the
  layers. We modelled the terraces as a family of concentric ellipsoidal
  shells with fixed axis ratios, producing a model that is completely
  defined by just eight free parameters. Each lobe of 67P has been
  modelled independently, and the two sets of parameters have been
  estimated by means of non-linear optimization of the measured terrace
  orientations. The proposed model is able to predict the orientation of
  terraces, the elongation of cliffs, the linear traces observed in the
  Wosret and Hathor regions and the peculiar alignment of boulder-like
  features which has been observed in the Hapi region, which appears to
  be related to the inner layering of the big lobe. Our analysis allowed
  us to identify a plane of junction between the two lobes, further
  confirming the independent nature of the lobes. Our layering models
  differ from the best-fitting topographic ellipsoids of the surface,
  demonstrating that the terraces are aligned to an internal structure of
  discontinuities, which is unevenly exposed on the surface, suggesting
  a complex history of localized material removal from the nucleus.

---------------------------------------------------------
Title: Geomorphological and spectrophotometric analysis of Seth's
    circular niches on comet 67P/Churyumov-Gerasimenko using OSIRIS images
Authors: Lucchetti, A.; Pajola, M.; Fornasier, S.; Mottola, S.; Penasa,
   L.; Jorda, L.; Cremonese, G.; Feller, C.; Hasselmann, P. H.; Massironi,
   M.; Ferrari, S.; Naletto, G.; Oklay, N.; Sierks, H.; Barbieri,
   C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller,
   H. U.; Agarwal, J.; A'Hearn, M. F.; Barucci, M. A.; Bertaux, J. L.;
   Bertini, I.; Boudreault, S.; Da Deppo, V.; Davidsson, B.; Debei, S.;
   De Cecco, M.; Deller, J.; Fulle, M.; Groussin, O.; Gutierrez, P. J.;
   Güttler, C.; Hoffman, M.; Hviid, S. F.; Ip, W. H.; Knollenberg, J.;
   Kramm, J. R.; Kührt, E.; Küppers, M.; Lara, L. M.; Lazzarin, M.;
   La Forgia, F.; Lin, L. Z.; Lopez Moreno, J. J.; Marzari, F.; Preusker,
   F.; Scholten, F.; Shi, X.; Thomas, N.; Tubiana, C.; Vincent, J. B.
2017MNRAS.469S.238L    Altcode:
  We provide a detailed geomorphological and spectrophotometric analysis
  of the circular niches located on the Seth region of 67P using OSIRIS
  images. The features can be related to landslide events that occurred
  on 67P and shaped its surface, as the recent Aswan cliff collapse
  detected in the same region. We therefore provide an analysis of the
  area pre- and post-perihelion suggesting that no specific changes have
  been observed. To assess this, after performing a geomorphological
  map of the area that allows us to identify different terrain units,
  we computed the boulders cumulative size frequency distribution (SFD)
  of the niches, before and after the perihelion passage. The niches
  SFDs are characterized by a similar trend with two different power-law
  indices within the same deposit: lower power-law value (between -2.3
  and -2.7) for boulders smaller than 5 m and steeper power-law value
  (between -4.7 and -5.0) for boulders larger than 5 m. These trends
  suggest that smaller boulders have evolved and progressively have
  been depleted (lower power-law index), while bigger boulders are more
  representative of the event that generated the deposit and are less
  degraded. Then, we perform the spectrophotometric analysis of this
  region comparing pre- and post-perihelion results. We found colour
  changes within the area, in particular brighter patches related to
  the presence of exposed water ice mixed to the refractory materials
  have been detected in the post-perihelion images.

---------------------------------------------------------
Title: Thermal modelling of water activity on comet
    67P/Churyumov-Gerasimenko with global dust mantle and plural
    dust-to-ice ratio
Authors: Hu, X.; Shi, X.; Sierks, H.; Blum, J.; Oberst, J.; Fulle,
   M.; Kührt, E.; Güttler, C.; Gundlach, B.; Keller, H. U.; Mottola,
   S.; Pajola, M.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.;
   Rickman, H.; Agarwal, J.; A'Hearn, M. F.; Barucci, M. A.; Bertaux,
   J. -L.; Bertini, I.; Boudreault, S.; Büttner, I.; Cremonese, G.;
   Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.; Deller, J.;
   Fornasier, S.; Groussin, O.; Gutiérrez, P. J.; Gutiérrez-Marqués,
   P.; Hall, I.; Hofmann, M.; Hviid, S. F.; Ip, W. -H.; Jorda, L.;
   Knollenberg, J.; Kovacs, G.; Kramm, J. R.; Küppers, M.; Lara, L. M.;
   Lazzarin, M.; López-Moreno, J. J.; Marzari, F.; Naletto, G.; Oklay,
   N.; Richards, M. L.; Ripken, J.; Thomas, N.; Tubiana, C.; Vincent,
   J. -B.
2017MNRAS.469S.295H    Altcode:
  We perform a thermo-physical analysis on water activity of comet
  67P/Churyumov-Gerasimenko (67P). The sublimation of water is
  assumed to occur from beneath a global, desiccated dust mantle over
  the irregular-shaped nucleus. The concept of two thermal models,
  the recipe of model formulation and the strategy of application to
  comet 67P are described. For an accurate and efficient evaluation
  of energy input by insolation and self-heating over the nucleus, a
  Landscape data base is devised based on polyhedral shape models of
  the nucleus. We apply the thermal models to investigate the impact
  of certain parameters of nucleus properties on water production. It
  is found that the measured water production of 67P can be overall
  attributed to sublimation of water ice with a mass abundance of a few
  to 10 per cent beneath a uniform dust mantle of several millimetres
  to one centimetre in thickness. Insofar as 67P is concerned, we argue
  against the necessity to invoke assumptions on localized water activity,
  or on the distinction of active/dormant surface areas.

---------------------------------------------------------
Title: Anomalous Surge of the White-Light Corona at the Onset of
    the Declining Phase of Solar Cycle 24
Authors: Lamy, P.; Boclet, B.; Wojak, J.; Vibert, D.
2017SoPh..292...60L    Altcode:
  In late 2014, when the current Solar Cycle 24 entered its declining
  phase, the white-light corona as observed by the LASCO-C2 coronagraph
  underwent an unexpected surge that increased its global radiance
  by 60%, reaching a peak value comparable to the peak values of the
  more active Solar Cycle 23. A comparison of the temporal variation
  of the white-light corona with the variations of several indices and
  proxies of solar activity indicate that it best matches the variation
  of the total magnetic field. The daily variations point to a localized
  enhancement or bulge in the electron density that persisted for several
  months. Carrington maps of the radiance and of the HMI photospheric
  field allow connecting this bulge to the emergence of the large
  sunspot complex AR 12192 in October 2014, the largest since AR 6368
  observed in November 1990. The resulting unusually high increase
  of the magnetic field and the distortion of the neutral sheet in a
  characteristic inverse S-shape caused the coronal plasma to be trapped
  along a similar pattern. A 3D reconstruction of the electron density
  based on time-dependent solar rotational tomography supplemented by
  2D inversion of the coronal radiance confirms the morphology of the
  bulge and reveals that its level was well above the standard models
  of a corona of the maximum type, by typically a factor of 3. A rather
  satisfactory agreement is found with the results of the thermodynamic
  MHD model produced by Predictive Sciences, although discrepancies
  are noted. The specific configuration of the magnetic field that led
  to the coronal surge resulted from the interplay of various factors
  prevailing at the onset of the declining phase of the solar cycles,
  which was particularly efficient in the case of Solar Cycle 24.

---------------------------------------------------------
Title: Multivariate statistical analysis of OSIRIS/Rosetta
    spectrophotometric data of comet 67P/Churyumov-Gerasimenko
Authors: Perna, D.; Fulchignoni, M.; Barucci, M. A.; Fornasier, S.;
   Feller, C.; Deshapriya, J. D. P.; Hasselmann, P. H.; Sierks, H.;
   Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.;
   A'Hearn, M.; Bertaux, J. -L.; Bertini, I.; Cremonese, G.; Da Deppo,
   V.; Davidsson, B.; Debei, S.; Deller, J.; De Cecco, M.; El-Maarry,
   M. R.; Fulle, M.; Groussin, O.; Gutierrez, P. J.; Güttler, C.;
   Hofmann, M.; Hviid, S. F.; Ip, W. -H.; Jorda, L.; Keller, H. U.;
   Knollenberg, J.; Kramm, R.; Kührt, E.; Küppers, M.; Lara, L. M.;
   Lazzarin, M.; Lopez Moreno, J. J.; Marzari, F.; Naletto, G.; Oklay,
   N.; Thomas, N.; Tubiana, C.; Vincent, J. -B.
2017A&A...600A.115P    Altcode:
  Context. The ESA Rosetta mission explored comet
  67P/Churyumov-Gerasimenko in 2014-2016, following its target before
  and after the perihelion passage on 13 August 2015. The NAC camera of
  the OSIRIS imaging system allowed to map the nucleus surface acquiring
  images with different filters in the visible wavelength range. <BR />
  Aims: Here we study the spectrophotometric behaviour of the nucleus
  by a multivariate statistical analysis, aiming to distinguish
  homogeneous groups and to constrain the bulk composition. <BR />
  Methods: We applied the G-mode clustering algorithm to 16 OSIRIS
  data cubes acquired on 5-6 August 2014 (mostly covering the northern
  hemisphere) and 2 May 2015 (mostly covering the southern hemisphere),
  selected to have complete coverage of the comet's surface with similar
  observing conditions. <BR /> Results: We found four similar homogeneous
  groups for each of the analysed cubes. The first group corresponds
  to the average spectrophotometric behaviour of the nucleus. The
  second (spectrally redder) and the third (spectrally bluer) groups
  are found in regions that were already found to deviate from the
  average terrain of the comet by previous studies. A fourth group
  (characterised by enhancements of the flux at 700-750 nm and 989 nm,
  possibly due to H<SUB>2</SUB>O<SUP>+</SUP> and/or NH<SUB>2</SUB>
  emissions) seems connected with the cometary activity rather than
  with the bulk composition. <BR /> Conclusions: While our aim in this
  work was to study the spectrophotometric behaviour of the nucleus
  of 67P/Churyumov-Gerasimenko as a whole, we found that a follow-up
  application of the G-mode to smaller regions of the surface could
  be useful in particular to identify and study the temporal evolution
  of ice patches, as well as to constrain the composition and physical
  processes behind the emission of dust jets.

---------------------------------------------------------
Title: Opposition effect on comet 67P/Churyumov-Gerasimenko using
    Rosetta-OSIRIS images
Authors: Masoumzadeh, N.; Oklay, N.; Kolokolova, L.; Sierks, H.;
   Fornasier, S.; Barucci, M. A.; Vincent, J. -B.; Tubiana, C.; Güttler,
   C.; Preusker, F.; Scholten, F.; Mottola, S.; Hasselmann, P. H.; Feller,
   C.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.;
   A'Hearn, M. F.; Bertaux, J. -L.; Bertini, I.; Cremonese, G.; Da Deppo,
   V.; Davidsson, B. J. R.; Debei, S.; De Cecco, M.; Fulle, M.; Gicquel,
   A.; Groussin, O.; Gutiérrez, P. J.; Hall, I.; Hofmann, M.; Hviid,
   S. F.; Ip, W. -H.; Jorda, L.; Keller, H. U.; Knollenberg, J.; Kovacs,
   G.; Kramm, J. -R.; Kührt, E.; Küppers, M.; Lara, L. M.; Lazzarin,
   M.; Lopez Moreno, J. J.; Marzari, F.; Naletto, G.; Shi, X.; Thomas, N.
2017A&A...599A..11M    Altcode:
  <BR /> Aims: We aim to explore the behavior of the opposition effect as
  an important tool in optical remote sensing on the nucleus of comet 67P/
  Churyumov-Gerasimenko (67P), using Rosetta-OSIRIS images acquired in
  different filters during the approach phase, July-August 2014 and the
  close flyby images on 14 of February 2015, which contain the spacecraft
  shadow. <BR /> Methods: We based our investigation on the global and
  local brightness from the surface of 67P with respect to the phase
  angle, also known as phase curve. The local phase curve corresponds to
  a region that is located at the Imhotep-Ash boundary of 67P. Assuming
  that the region at the Imhotep-Ash boundary and the entire nucleus
  have similar albedo, we combined the global and local phase curves to
  study the opposition-surge morphology and constrain the structure and
  properties of 67P. The model parameters were furthermore compared with
  other bodies in the solar system and existing laboratory study. <BR />
  Results: We found that the morphological parameters of the opposition
  surge decrease monotonically with wavelength, whereas in the case of
  coherent backscattering this behavior should be the reverse. The results
  from comparative analysis place 67P in the same category as the two
  Mars satellites, Phobos and Deimos, which are notably different from
  all airless bodies in the solar system. The similarity between the
  surface phase function of 67P and a carbon soot sample at extremely
  small angles is identified, introducing regolith at the boundary of
  the Imhotep-Ash region of 67P as a very dark and fluffy layer.

---------------------------------------------------------
Title: Surface changes on comet 67P/Churyumov-Gerasimenko suggest
    a more active past
Authors: El-Maarry, M. Ramy; Groussin, O.; Thomas, N.; Pajola, M.;
   Auger, A. -T.; Davidsson, B.; Hu, X.; Hviid, S. F.; Knollenberg, J.;
   Güttler, C.; Tubiana, C.; Fornasier, S.; Feller, C.; Hasselmann, P.;
   Vincent, J. -B.; Sierks, H.; Barbieri, C.; Lamy, P.; Rodrigo, R.;
   Koschny, D.; Keller, H. U.; Rickman, H.; A'Hearn, M. F.; Barucci,
   M. A.; Bertaux, J. -L.; Bertini, I.; Besse, S.; Bodewits, D.;
   Cremonese, G.; Da Deppo, V.; Debei, S.; De Cecco, M.; Deller, J.;
   Deshapriya, J. D. P.; Fulle, M.; Gutierrez, P. J.; Hofmann, M.; Ip,
   W. -H.; Jorda, L.; Kovacs, G.; Kramm, J. -R.; Kührt, E.; Küppers, M.;
   Lara, L. M.; Lazzarin, M.; Lin, Z. -Yi; Lopez Moreno, J. J.; Marchi,
   S.; Marzari, F.; Mottola, S.; Naletto, G.; Oklay, N.; Pommerol, A.;
   Preusker, F.; Scholten, F.; Shi, X.
2017Sci...355.1392E    Altcode:
  The Rosetta spacecraft spent ~2 years orbiting comet
  67P/Churyumov-Gerasimenko, most of it at distances that allowed surface
  characterization and monitoring at submeter scales. From December
  2014 to June 2016, numerous localized changes were observed, which
  we attribute to cometary-specific weathering, erosion, and transient
  events driven by exposure to sunlight and other processes. While the
  localized changes suggest compositional or physical heterogeneity,
  their scale has not resulted in substantial alterations to the
  comet’s landscape. This suggests that most of the major landforms were
  created early in the comet’s current orbital configuration. They may
  even date from earlier if the comet had a larger volatile inventory,
  particularly of CO or CO<SUB>2</SUB> ices, or contained amorphous ice,
  which could have triggered activity at greater distances from the Sun.

---------------------------------------------------------
Title: The pristine interior of comet 67P revealed by the combined
    Aswan outburst and cliff collapse
Authors: Pajola, M.; Höfner, S.; Vincent, J. B.; Oklay, N.; Scholten,
   F.; Preusker, F.; Mottola, S.; Naletto, G.; Fornasier, S.; Lowry, S.;
   Feller, C.; Hasselmann, P. H.; Güttler, C.; Tubiana, C.; Sierks, H.;
   Barbieri, C.; Lamy, P.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller,
   H. U.; Agarwal, J.; A'Hearn, M. F.; Barucci, M. A.; Bertaux, J. -L.;
   Bertini, I.; Besse, S.; Boudreault, S.; Cremonese, G.; da Deppo,
   V.; Davidsson, B.; Debei, S.; de Cecco, M.; Deller, J.; Deshapriya,
   J. D. P.; El-Maarry, M. R.; Ferrari, S.; Ferri, F.; Fulle, M.;
   Groussin, O.; Gutierrez, P.; Hofmann, M.; Hviid, S. F.; Ip, W. -H.;
   Jorda, L.; Knollenberg, J.; Kovacs, G.; Kramm, J. R.; Kührt, E.;
   Küppers, M.; Lara, L. M.; Lin, Z. -Y.; Lazzarin, M.; Lucchetti, A.;
   Lopez Moreno, J. J.; Marzari, F.; Massironi, M.; Michalik, H.; Penasa,
   L.; Pommerol, A.; Simioni, E.; Thomas, N.; Toth, I.; Baratti, E.
2017NatAs...1E..92P    Altcode:
  Outbursts occur commonly on comets<SUP>1</SUP> with different
  frequencies and scales<SUP>2,3</SUP>. Despite multiple observations
  suggesting various triggering processes<SUP>4,5</SUP>, the driving
  mechanism of such outbursts is still poorly understood. Landslides have
  been invoked<SUP>6</SUP> to explain some outbursts on comet 103P/Hartley
  2, although the process required a pre-existing dust layer on the
  verge of failure. The Rosetta mission observed several outbursts from
  its target comet 67P/Churyumov-Gerasimenko, which were attributed
  to dust generated by the crumbling of materials from collapsing
  cliffs<SUP>7,8</SUP>. However, none of the aforementioned works included
  definitive evidence that landslides occur on comets. Amongst the many
  features observed by Rosetta on the nucleus of the comet, one peculiar
  fracture, 70 m long and 1 m wide, was identified on images obtained
  in September 2014 at the edge of a cliff named Aswan<SUP>9</SUP>. On
  10 July 2015, the Rosetta Navigation Camera captured a large plume
  of dust that could be traced back to an area encompassing the Aswan
  escarpment<SUP>7</SUP>. Five days later, the OSIRIS camera observed
  a fresh, sharp and bright edge on the Aswan cliff. Here we report
  the first unambiguous link between an outburst and a cliff collapse
  on a comet. We establish a new dust-plume formation mechanism that
  does not necessarily require the breakup of pressurized crust or
  the presence of supervolatile material, as suggested by previous
  studies<SUP>7</SUP>. Moreover, the collapse revealed the fresh icy
  interior of the comet, which is characterized by an albedo &gt;0.4,
  and provided the opportunity to study how the crumbling wall settled
  down to form a new talus.

---------------------------------------------------------
Title: Different Origins or Different Evolutions? Decoding the
    Spectral Diversity Among C-type Asteroids
Authors: Vernazza, P.; Castillo-Rogez, J.; Beck, P.; Emery, J.;
   Brunetto, R.; Delbo, M.; Marsset, M.; Marchis, F.; Groussin, O.;
   Zanda, B.; Lamy, P.; Jorda, L.; Mousis, O.; Delsanti, A.; Djouadi,
   Z.; Dionnet, Z.; Borondics, F.; Carry, B.
2017AJ....153...72V    Altcode: 2017arXiv170106603V
  Anhydrous pyroxene-rich interplanetary dust particles (IDPs) have been
  proposed as surface analogs for about two-thirds of all C-complex
  asteroids. However, this suggestion appears to be inconsistent with
  the presence of hydrated silicates on the surfaces of some of these
  asteroids, including Ceres. Here, we report the presence of enstatite
  (pyroxene) on the surface of two C-type asteroids (Ceres and Eugenia)
  based on their spectral properties in the mid-infrared range. The
  presence of this component is particularly unexpected in the case
  of Ceres, because most thermal evolution models predict a surface
  consisting of hydrated compounds only. The most plausible scenario is
  that Ceres’ surface has been partially contaminated by exogenous
  enstatite-rich material, possibly coming from the Beagle asteroid
  family. This scenario questions a similar origin for Ceres and the
  remaining C-types, and it possibly supports recent results obtained
  by the Dawn mission (NASA) that Ceres may have formed in the very
  outer solar system. Concerning the smaller D ∼ 200 km C-types such as
  Eugenia, both their derived surface composition (enstatite and amorphous
  silicates) and low density (&lt;1.5 g cm<SUP>-3</SUP>) suggest that
  these bodies accreted from the same building blocks, namely chondritic
  porous, pyroxene-rich IDPs and volatiles (mostly water ice), and that a
  significant volume fraction of these bodies has remained unaffected by
  hydrothermal activity likely implying a late accretion. In addition,
  their current heliocentric distance may best explain the presence
  or absence of water ice at their surfaces. Finally, we raise the
  possibility that CI chondrites, Tagish-Lake-like material, or hydrated
  IDPs may be representative samples of the cores of these bodies.

---------------------------------------------------------
Title: Regional surface morphology of comet 67P/Churyumov-Gerasimenko
from Rosetta/OSIRIS images: The southern hemisphere (Corrigendum)
Authors: El-Maarry, M. R.; Thomas, N.; Gracia-Berná, A.; Pajola,
   M.; Lee, J. -C.; Massironi, M.; Davidsson, B.; Marchi, S.; Keller,
   H. U.; Hviid, S. F.; Besse, S.; Sierks, H.; Barbieri, C.; Lamy,
   P. L.; Koschny, D.; Rickman, H.; Rodrigo, R.; A'Hearn, M. F.; Auger,
   A. -T.; Barucci, M. A.; Bertaux, J. -L.; Bertini, I.; Bodewits, D.;
   Cremonese, G.; Da Deppo, V.; De Cecco, M.; Debei, S.; Güttler, C.;
   Fornasier, S.; Fulle, M.; Giacomini, L.; Groussin, O.; Gutierrez,
   P. J.; Ip, W. -H.; Jorda, L.; Knollenberg, J.; Kovacs, G.; Kramm,
   J. -R.; Kührt, E.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Lopez
   Moreno, J. J.; Marschall, R.; Marzari, F.; Naletto, G.; Oklay, N.;
   Pommerol, A.; Preusker, F.; Scholten, F.; Tubiana, C.; Vincent, J. -B.
2017A&A...598C...2E    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Coronal mass ejections and solar wind mass fluxes over the
    heliosphere during solar cycles 23 and 24 (1996-2014)
Authors: Lamy, P.; Floyd, O.; Quémerais, E.; Boclet, B.; Ferron, S.
2017JGRA..122...50L    Altcode:
  Coronal mass ejections (CMEs) play a major role in the heliosphere,
  and their contribution to the solar wind mass flux, already considered
  in the Skylab and Solwind eras with conflicting results, is reexamined
  in the light of 19 years (1996-2014) of SOHO observations with the Large
  Angle and Spectroscopic Coronagraph (LASCO-C2) for the CMEs and extended
  for the first time to all latitudes thanks to the whole-heliosphere data
  from the Solar Wind ANisotropies (SWAN) instrument supplemented by in
  situ data aggregated in the OMNI database. First, several mass estimates
  reported in the ARTEMIS (Automated Recognition of Transient Events
  and Marseille Inventory from Synoptic maps) catalog of LASCO CMEs are
  compared with determinations based on the combined observations with the
  twin STEREO/Sun Earth Connection Coronal and Heliospheric Investigation
  coronagraphs in order to ascertain their validity. A simple geometric
  model of the CMEs is introduced to generate Carrington maps of their
  mass flux and then to produce annualized synoptic maps. The Lyman
  α SWAN data are inverted to similarly produce synoptic maps to be
  compared with those of the CME flux. The ratio of the annualized CME
  to solar wind mass flux is found to closely track the solar cycle over
  the heliosphere. In the near-ecliptic region and at latitudes up to
  ∼55°, this ratio was negligibly small during the solar minima of
  cycles 22/23 and 23/24 and rose to 6% and 5%, respectively, at the
  maximum of solar cycles 23 and 24. These maximum ratios increased at
  higher latitudes, but this result is likely biased by the inherent
  limitation of determining the true latitude of CMEs.

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Title: A mini outburst from the nightside of comet
    67P/Churyumov-Gerasimenko observed by the OSIRIS camera on Rosetta
Authors: Knollenberg, J.; Lin, Z. Y.; Hviid, S. F.; Oklay, N.; Vincent,
   J. -B.; Bodewits, D.; Mottola, S.; Pajola, M.; Sierks, H.; Barbieri,
   C.; Lamy, P.; Rodrigo, R.; Koschny, D.; Rickman, H.; A'Hearn, M. F.;
   Barucci, M. A.; Bertaux, J. L.; Bertini, I.; Cremonese, G.; Davidsson,
   B.; Da Deppo, V.; Debei, S.; De Cecco, M.; Fornasier, S.; Fulle, M.;
   Groussin, O.; Gutiérrez, P. J.; Ip, W. -H.; Jorda, L.; Keller, H. U.;
   Kührt, E.; Kramm, J. R.; Küppers, M.; Lara, L. M.; Lazzarin, M.;
   Lopez Moreno, J. J.; Marzari, F.; Naletto, G.; Thomas, N.; Güttler,
   C.; Preusker, F.; Scholten, F.; Tubiana, C.
2016A&A...596A..89K    Altcode:
  Context. On 12 March 2015 the OSIRIS WAC camera onboard the ESA
  Rosetta spacecraft orbiting comet 67P/Churyumov-Gerasimenko observed
  a small outburst originating from the Imhotep region at the foot of
  the big lobe of the comet. These measurements are unique since it was
  the first time that the initial phase of a transient outburst event
  could be directly observed. <BR /> Aims: We investigate the evolution
  of the dust jet in order to derive clues about the outburst source
  mechanism and the ejected dust particles, in particular the dust
  mass, dust-to-gas ratio and the particle size distribution. <BR />
  Methods: Analysis of the images and of the observation geometry using
  comet shape models in combination with gasdynamic modeling of the
  transient dust jet were the main tools used in this study. Synthetic
  images were computed for comparison with the observations. <BR />
  Results: Analysis of the geometry revealed that the source region was
  not illuminated until 1.5 h after the event implying true nightside
  activity was observed. The outburst lasted for less than one hour and
  the average dust production rate during the initial four minutes was
  of the order of 1 kg/s. During this time the outburst dust production
  rate was approximately constant, no sign for an initial explosion
  could be detected. For dust grains between 0.01-1 mm a power law size
  distribution characterized by an index of about 2.6 provides the best
  fit to the observed radiance profiles. The dust-to-gas ratio of the
  outburst jet is in the range 0.6-1.8.

---------------------------------------------------------
Title: Rosetta’s comet 67P/Churyumov-Gerasimenko sheds its dusty
    mantle to reveal its icy nature
Authors: Fornasier, S.; Mottola, S.; Keller, H. U.; Barucci, M. A.;
   Davidsson, B.; Feller, C.; Deshapriya, J. D. P.; Sierks, H.; Barbieri,
   C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; A'Hearn, M.;
   Agarwal, J.; Bertaux, J. -L.; Bertini, I.; Besse, S.; Cremonese, G.;
   Da Deppo, V.; Debei, S.; De Cecco, M.; Deller, J.; El-Maarry, M. R.;
   Fulle, M.; Groussin, O.; Gutierrez, P. J.; Güttler, C.; Hofmann,
   M.; Hviid, S. F.; Ip, W. -H.; Jorda, L.; Knollenberg, J.; Kovacs,
   G.; Kramm, R.; Kührt, E.; Küppers, M.; Lara, M. L.; Lazzarin, M.;
   Moreno, J. J. Lopez; Marzari, F.; Massironi, M.; Naletto, G.; Oklay,
   N.; Pajola, M.; Pommerol, A.; Preusker, F.; Scholten, F.; Shi, X.;
   Thomas, N.; Toth, I.; Tubiana, C.; Vincent, J. -B.
2016Sci...354.1566F    Altcode:
  The Rosetta spacecraft has investigated comet 67P/Churyumov-Gerasimenko
  from large heliocentric distances to its perihelion passage and
  beyond. We trace the seasonal and diurnal evolution of the colors of the
  67P nucleus, finding changes driven by sublimation and recondensation of
  water ice. The whole nucleus became relatively bluer near perihelion,
  as increasing activity removed the surface dust, implying that water
  ice is widespread underneath the surface. We identified large (1500
  square meters) ice-rich patches appearing and then vanishing in about
  10 days, indicating small-scale heterogeneities on the nucleus. Thin
  frosts sublimating in a few minutes are observed close to receding
  shadows, and rapid variations in color are seen on extended areas
  close to the terminator. These cyclic processes are widespread and
  lead to continuously, slightly varying surface properties.

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Title: Mapping of the source regions of the dust jets on comet
    67P/Churyumov-Gerasimenko
Authors: Lai, I. L.; Ip, W. H.; Lee, J. C.; Lin, Z. Y.; Vincent,
   J. B.; Hartogh, P.; Sierks, H.; Barbieri, C.; Lamy, P. L.; Rickman,
   H.; Keller, H. U.
2016AGUFM.P43A2087L    Altcode:
  Because of the inclination of the rotational axis to the orbital
  plane and the orbital motion around the Sun, the sunlit regions on
  the nucleus surface of comet 67P/Churyumov-Gerasimenko moved from
  the northern hemisphere to the sourthern hemisphere between August,
  2014 and August, 2015. From the comparison of the dust jet features in
  images taken at successive time series, the footpoints of these jets
  can be identified by a projection method. The distributiosn of the
  corresponding source regions can be compared with the geomorphology
  of the nucleus surface from inbound to outbound. The correlation
  of the dust jet activity with the volatile outgassing phenomenon as
  monitored by different scientific instruments onboard Rosetta will
  provide important information on the sublimation process.

---------------------------------------------------------
Title: Gas outflow and dust transport of comet
    67P/Churyumov-Gerasimenko
Authors: Lai, Ian-Lin; Ip, Wing-Huen; Su, Cheng-Chin; Wu, Jong-Shinn;
   Lee, Jui-Chi; Lin, Zhong-Yi; Liao, Ying; Thomas, Nicolas; Sierks,
   Holger; Barbieri, Cesare; Lamy, Philippe; Rodrigo, Rafael; Koschny,
   Detlef; Rickman, Hans; Keller, Horst Uwe; Agarwal, Jessica; A'Hearn,
   Michael F.; Barucci, Maria Antonella; Bertaux, Jean-Loup; Bertini,
   Ivano; Boudreault, Steven; Cremonese, Gabriele; Da Deppo, Vania;
   Davidsson, Björn; Debei, Stefano; De Cecco, Mariolino; Deller, Jakob;
   Fornasier, Sonia; Fulle, Marco; Groussin, Olivier; Gutiérrez, Pedro
   J.; Güttler, Carsten; Hofmann, Marc; Hviid, Stubbe F.; Jorda, Laurent;
   Knollenberg, Jörg; Kovacs, Gabor; Kramm, J. -Rainer; Kührt, Ekkehard;
   Küppers, Michael; Lara, Luisa M.; Lazzarin, Monica; Lopez Moreno,
   Josè J.; Marzari, Francesco; Naletto, Giampiero; Oklay, Nilda; Shi,
   Xian; Tubiana, Cecilia; Vincent, Jean-Baptiste
2016MNRAS.462S.533L    Altcode:
  Because of the diurnal thermal cycle and the irregular shape of the
  nucleus, gas outflow of comet 67P/Churyumov-Gerasimenko could be highly
  anisotropic as indicated by the colliminated dust jet structures
  on the sunlit side. Based on the OSIRIS imaging observations of
  the outgassing effect, a simple model of surface sublimation can
  be constructed by taking into account the dependence on the solar
  insolation. With preliminary information on the time variability of
  the global gas production rate, a sequence of gas coma models can be
  generated at different epochs before and after perihelion. We also
  investigate different patterns of dust particle dynamics under the
  influences of nuclear rotation and gas drag. From these considerations,
  a consistent picture of the spatial distribution of dusty materials
  across the surface of comet 67P as it moves around the perihelion can be
  developed. It is found that because of the redeposition of the ejected
  dust from the Southern hemisphere to the Northern hemisphere during
  the southern summer season the Hapi region could gain up to 0.4 m
  while the Wosret region would lose up to 1.8 m of dust mantle per orbit.

---------------------------------------------------------
Title: Comparative study of water ice exposures on cometary nuclei
    using multispectral imaging data
Authors: Oklay, N.; Sunshine, J. M.; Pajola, M.; Pommerol, A.;
   Vincent, J. -B.; Mottola, S.; Sierks, H.; Fornasier, S.; Barucci,
   M. A.; Preusker, F.; Scholten, F.; Lara, L. M.; Barbieri, C.;
   Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; A'Hearn, M. F.;
   Bertaux, J. -L.; Bertini, I.; Bodewits, D.; Cremonese, G.; Da Deppo,
   V.; Davidsson, B. J. R.; Debei, S.; De Cecco, M.; Deller, J.; Fulle,
   M.; Gicquel, A.; Groussin, O.; Gutiérrez, P. J.; Güttler, C.; Hall,
   I.; Hofmann, M.; Hviid, S. F.; Ip, W. -H.; Jorda, L.; Keller, H. U.;
   Knollenberg, J.; Kovacs, G.; Kramm, J. -R.; Kührt, E.; Küppers, M.;
   Lazzarin, M.; Lin, Z. -Y.; Lopez Moreno, J. J.; Marzari, F.; Naletto,
   G.; Shi, X.; Thomas, N.; Tubiana, C.
2016MNRAS.462S.394O    Altcode:
  Deep Impact, EPOXI and Rosetta missions visited comets 9P/Tempel 1,
  103P/Hartley 2 and 67P/Churyumov-Gerasimenko, respectively. Each of
  these three missions was equipped with both multispectral imagers and
  infrared spectrometers. Bright blue features containing water ice were
  detected in each of these comet nuclei. We analysed multispectral
  properties of enriched water ice features observed via Optical,
  Spectroscopic, and Infrared Remote Imaging System narrow angle camera
  on comet 67P in the wavelength range of 260-1000 nm and then compared
  with multispectral data of water ice deposits observed on comets 9P and
  103P. We characterize the UV/VIS properties of water-ice-rich features
  observed on the nuclei of these three comets. When compared to the
  average surface of each comet, our analysis shows that the water ice
  deposits seen on comet 9P are similar to the clustered water-ice-rich
  features seen on comet 67P, while the water ice deposit seen on comet
  103P is more akin to two large isolated water-ice-rich features seen
  on comet 67P. Our results indicate that the water ice deposit observed
  on comet 103P contains more water ice than the water-ice-rich features
  observed on comets 9P and 67P, proportionally to the average surface
  of each nucleus.

---------------------------------------------------------
Title: Spectrophotometry of the Khonsu region on the comet
    67P/Churyumov-Gerasimenko using OSIRIS instrument images
Authors: Deshapriya, J. D. P.; Barucci, M. A.; Fornasier, S.; Feller,
   C.; Hasselmann, P. H.; Sierks, H.; El-Maarry, M. R.; Pajola, M.;
   Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.;
   Agarwal, J.; A'Hearn, M. F.; Bertaux, J. -L.; Bertini, I.; Boudreault,
   S.; Cremonese, G.; Da Deppo, V.; Davidsson, B. J. R.; Debei, S.;
   Deller, J.; De Cecco, M.; Fulle, M.; Gicquel, A.; Groussin, O.;
   Gutierrez, P. J.; Güttler, C.; Hofmann, M.; Hviid, S. F.; Ip, W.;
   Jorda, L.; Keller, H. U.; Knollenberg, J.; Kramm, R.; Kührt, E.;
   Küppers, M.; Lara, L.; Lazzarin, M.; Lopez Moreno, J. J.; Marzari,
   F.; Mottola, S.; Naletto, G.; Oklay, N.; Perna, D.; Pommerol, A.;
   Thomas, N.; Tubiana, C.; Vincent, J. -B.
2016MNRAS.462S.274D    Altcode: 2016MNRAS.tmp.1515D
  Our work focuses on the spectrophotometric analysis of selected
  terrain and bright patches in the Khonsu region on the comet
  67P/Churyumov-Gerasimenko. Despite the variety of geological features,
  their spectrophotometric properties appear to indicate a similar
  composition. It is noticeable that the smooth areas in Khonsu possess
  similar spectrophotometric behaviour to some other regions of the
  comet. We observed bright patches on Khonsu with an estimation of
  &gt;40 per cent of normal albedo and suggest that they are associated
  with H<SUB>2</SUB>O ice. One of the studied bright patches has been
  observed to exist on the surface for more than 5 months without a major
  decay of its size, implying the existence of potential sub-surface icy
  layers. Its location may be correlated with a cometary outburst during
  the perihelion passage of the comet in 2015 August, and we interpret
  it to have triggered the surface modifications necessary to unearth
  the stratified icy layers beneath the surface. A boulder analysis
  on Khonsu leads to a power-law index of -3.1 +0.2/-0.3 suggesting a
  boulder formation, shaped by varying geological processes for different
  morphological units.

---------------------------------------------------------
Title: Acceleration of individual, decimetre-sized aggregates in
    the lower coma of comet 67P/Churyumov-Gerasimenko
Authors: Agarwal, Jessica; A'Hearn, M. F.; Vincent, J. -B.; Güttler,
   C.; Höfner, S.; Sierks, H.; Tubiana, C.; Barbieri, C.; Lamy, P. L.;
   Rodrigo, R.; Koschny, D.; Rickman, H.; Barucci, M. A.; Bertaux, J. -L.;
   Bertini, I.; Boudreault, S.; Cremonese, G.; Da Deppo, V.; Davidsson,
   B.; Debei, S.; De Cecco, M.; Deller, J.; Fornasier, S.; Fulle, M.;
   Gicquel, A.; Groussin, O.; Gutiérrez, P. J.; Hofmann, M.; Hviid,
   S. F.; Ip, W. -H.; Jorda, L.; Keller, H. U.; Knollenberg, J.; Kramm,
   J. -R.; Kührt, E.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Lopez
   Moreno, J. J.; Marzari, F.; Naletto, G.; Oklay, N.; Shi, X.; Thomas, N.
2016MNRAS.462S..78A    Altcode: 2016MNRAS.tmp.1292A; 2016arXiv160807933A
  We present observations of decimetre-sized, likely ice-containing
  aggregates ejected from a confined region on the surface of comet
  67P/Churyumov-Gerasimenko. The images were obtained with the narrow
  angle camera of the Optical, Spectroscopic, and Infrared Remote
  Imaging System on board the Rosetta spacecraft in 2016 January when
  the comet was at 2 au from the Sun outbound from perihelion. We
  measure the acceleration of individual aggregates through a 2 h image
  series. Approximately 50 per cent of the aggregates are accelerated
  away from the nucleus, and 50 per cent towards it, and likewise towards
  either horizontal direction. The accelerations are up to one order of
  magnitude stronger than local gravity, and are most simply explained by
  the combined effect of gas drag accelerating all aggregates upwards,
  and the recoil force from asymmetric outgassing, either from rotating
  aggregates with randomly oriented spin axes and sufficient thermal
  inertia to shift the temperature maximum away from an aggregate's
  subsolar region, or from aggregates with variable ice content. At
  least 10 per cent of the aggregates will escape the gravity field of
  the nucleus and feed the comet's debris trail, while others may fall
  back to the surface and contribute to the deposits covering parts
  of the Northern hemisphere. The rocket force plays a crucial role in
  pushing these aggregates back towards the surface. Our observations
  show the future back fall material in the process of ejection, and
  provide the first direct measurement of the acceleration of aggregates
  in the innermost coma (&lt;2 km) of a comet, where gas drag is still
  significant.

---------------------------------------------------------
Title: Changes in the Physical Environment of the Inner Coma of
    67P/Churyumov-Gerasimenko with Decreasing Heliocentric Distance
Authors: Bodewits, D.; Lara, L. M.; A'Hearn, M. F.; La Forgia, F.;
   Gicquel, A.; Kovacs, G.; Knollenberg, J.; Lazzarin, M.; Lin, Z. -Y.;
   Shi, X.; Snodgrass, C.; Tubiana, C.; Sierks, H.; Barbieri, C.; Lamy,
   P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller, H. U.; Barucci,
   M. A.; Bertaux, J. -L.; Bertini, I.; Boudreault, S.; Cremonese, G.;
   Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.; Fornasier,
   S.; Fulle, M.; Groussin, O.; Gutiérrez, P. J.; Güttler, C.; Hviid,
   S. F.; Ip, W. -H.; Jorda, L.; Kramm, J. -R.; Kührt, E.; Küppers,
   M.; López-Moreno, J. J.; Marzari, F.; Naletto, G.; Oklay, N.; Thomas,
   N.; Toth, I.; Vincent, J. -B.
2016AJ....152..130B    Altcode: 2016arXiv160705632B
  The Wide Angle Camera of the OSIRIS instrument on board the
  Rosetta spacecraft is equipped with several narrow-band filters
  that are centered on the emission lines and bands of various
  fragment species. These are used to determine the evolution of the
  production and spatial distribution of the gas in the inner coma of
  comet 67P with time and heliocentric distance, here between 2.6 and
  1.3 au pre-perihelion. Our observations indicate that the emission
  observed in the OH, O I, CN, NH, and NH<SUB>2</SUB> filters is mostly
  produced by dissociative electron impact excitation of different parent
  species. We conclude that CO<SUB>2</SUB> rather than H<SUB>2</SUB>O is
  a significant source of the [O I] 630 nm emission. A strong plume-like
  feature observed in the CN and O I filters is present throughout our
  observations. This plume is not present in OH emission and indicates
  a local enhancement of the CO<SUB>2</SUB>/H<SUB>2</SUB>O ratio by as
  much as a factor of 3. We observed a sudden decrease in intensity levels
  after 2015 March, which we attribute to decreased electron temperatures
  in the first few kilometers above the surface of the nucleus.

---------------------------------------------------------
Title: Summer fireworks on comet 67P
Authors: Vincent, J. -B.; A'Hearn, M. F.; Lin, Z. -Y.; El-Maarry,
   M. R.; Pajola, M.; Sierks, H.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.;
   Koschny, D.; Rickman, H.; Keller, H. U.; Agarwal, J.; Barucci, M. A.;
   Bertaux, J. -L.; Bertini, I.; Besse, S.; Bodewits, D.; Cremonese,
   G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.; Deller,
   J.; Fornasier, S.; Fulle, M.; Gicquel, A.; Groussin, O.; Gutiérrez,
   P. J.; Gutiérrez-Marquez, P.; Güttler, C.; Höfner, S.; Hofmann,
   M.; Hviid, S. F.; Ip, W. -H.; Jorda, L.; Knollenberg, J.; Kovacs,
   G.; Kramm, J. -R.; Kührt, E.; Küppers, M.; Lara, L. M.; Lazzarin,
   M.; Lopez Moreno, J. J.; Marzari, F.; Massironi, M.; Mottola, S.;
   Naletto, G.; Oklay, N.; Preusker, F.; Scholten, F.; Shi, X.; Thomas,
   N.; Toth, I.; Tubiana, C.
2016MNRAS.462S.184V    Altcode: 2016arXiv160907743V
  During its 2 yr mission around comet 67P/Churyumov-Gerasimenko, ESA's
  Rosetta spacecraft had the unique opportunity to follow closely a comet
  in the most active part of its orbit. Many studies have presented the
  typical features associated with the activity of the nucleus, such as
  localized dust and gas jets. Here, we report on series of more energetic
  transient events observed during the 3 months surrounding the comet's
  perihelion passage in 2015 August. We detected and characterized 34
  outbursts with the Rosetta cameras, one every 2.4 nucleus rotations. We
  identified three main dust plume morphologies associated with these
  events: a narrow jet, a broad fan, and more complex plumes featuring
  both previous types together. These plumes are comparable in scale
  and temporal variation to what has been observed on other comets. We
  present a map of the outbursts' source locations, and discuss the
  associated topography. We find that the spatial distribution sources
  on the nucleus correlate well with morphological region boundaries,
  especially in areas marked by steep scarps or cliffs. Outbursts occur
  either in the early morning or shortly after the local noon, indicating
  two potential processes: morning outbursts may be triggered by thermal
  stresses linked to the rapid change of temperature; afternoon events
  are most likely related to the diurnal or seasonal heat wave reaching
  volatiles buried under the first surface layer. In addition, we propose
  that some events can be the result of a completely different mechanism,
  in which most of the dust is released upon the collapse of a cliff.

---------------------------------------------------------
Title: The Agilkia boulders/pebbles size-frequency distributions:
    OSIRIS and ROLIS joint observations of 67P surface
Authors: Pajola, M.; Mottola, S.; Hamm, M.; Fulle, M.; Davidsson,
   B.; Güttler, C.; Sierks, H.; Naletto, G.; Arnold, G.; Grothues,
   H. -G.; Jaumann, R.; Michaelis, H.; Bibring, J. P.; Barbieri,
   C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller,
   H. U.; Agarwal, J.; A'Hearn, M. F.; Barucci, M. A.; Bertaux, J. L.;
   Bertini, I.; Boudreault, S.; Cremonese, G.; Da Deppo, V.; Debei, S.;
   De Cecco, M.; Deller, J.; El Maarry, M. R.; Feller, C.; Fornasier,
   S.; Gicquel, A.; Groussin, O.; Gutierrez, P. J.; Hofmann, M.; Hviid,
   S. F.; Ip, W. H.; Jorda, L.; Knollenberg, J.; Kramm, J. R.; Kührt,
   E.; Küppers, M.; La Forgia, F.; Lara, L. M.; Lin, Z. Y.; Lazzarin,
   M.; Lopez Moreno, J. J.; Lucchetti, A.; Marzari, F.; Massironi, M.;
   Michalik, H.; Oklay, N.; Pommerol, A.; Preusker, F.; Scholten, F.;
   Thomas, N.; Tubiana, C.; Vincent, J. B.
2016MNRAS.462S.242P    Altcode:
  By using the images acquired by the OSIRIS (Optical, Spectroscopic
  and Infrared Remote Imaging System) and ROLIS (ROsetta Lander Imaging
  System) cameras, we derive the size-frequency distribution (SFD) of
  cometary pebbles and boulders covering the size range 0.05-30.0 m on
  the Agilkia landing site. The global SFD measured on OSIRIS images,
  reflects the different properties of the multiple morphological
  units present on Agilkia, combined with selection effects related to
  lifting, transport and redeposition. Contrarily, the different ROLIS SFD
  derived on the smooth and rough units may be related to their different
  regolith thickness present on Agilkia. In the thicker, smoother layer,
  ROLIS mainly measures the SFD of the airfall population which almost
  completely obliterates the signature of underlying boulders up to a
  size of the order of 1 m. This is well matched by the power-law index
  derived analysing coma particles identified by the grain analyser
  Grain Impact Analyser and Dust Accumulator. This result confirms the
  important blanketing dynamism of Agilkia. The steeper SFD observed in
  rough terrains from 0.4 to 2 m could point out intrinsic differences
  between northern and southern dust size distributions, or it may
  suggest that the underlying boulders 'peek through' the thinner airfall
  layer in the rough terrain, thereby producing the observed excess
  in the decimetre size range. Eventually, the OSIRIS SFD performed on
  the Philae landing unit may be due to water sublimation from a static
  population of boulders, affecting smaller boulders before the bigger
  ones, thus shallowing the original SFD.

---------------------------------------------------------
Title: Decimetre-scaled spectrophotometric properties of the nucleus
    of comet 67P/Churyumov-Gerasimenko from OSIRIS observations
Authors: Feller, C.; Fornasier, S.; Hasselmann, P. H.; Barucci, A.;
   Preusker, F.; Scholten, F.; Jorda, L.; Pommerol, A.; Jost, B.; Poch,
   O.; ElMaary, M. R.; Thomas, N.; Belskaya, I.; Pajola, M.; Sierks,
   H.; Barbieri, C.; Lamy, P. L.; Koschny, D.; Rickman, H.; Rodrigo, R.;
   Agarwal, J.; A'Hearn, M.; Bertaux, J. -L.; Bertini, I.; Boudreault,
   S.; Cremonese, G.; Da Deppo, V.; Davidsson, B. J. R.; Debei, S.; De
   Cecco, M.; Deller, J.; Fulle, M.; Giquel, A.; Groussin, O.; Gutierrez,
   P. J.; Güttler, C.; Hofmann, M.; Hviid, S. F.; Keller, H.; Ip, W. -H.;
   Knollenberg, J.; Kovacs, G.; Kramm, J. -R.; Kührt, E.; Küppers, M.;
   Lara, M. L.; Lazzarin, M.; Leyrat, C.; Lopez Moreno, J. J.; Marzari,
   F.; Masoumzadeh, N.; Mottola, S.; Naletto, G.; Perna, D.; Oklay, N.;
   Shi, X.; Tubiana, C.; Vincent, J. -B.
2016MNRAS.462S.287F    Altcode: 2016arXiv161100012F
  We present the results of the photometric and spectrophotometric
  properties of the 67P/Churyumov-Gerasimenko nucleus derived with the
  Optical, Spectroscopic and Infrared Remote Imaging System instrument
  during the closest fly-by over the comet, which took place on 2015
  February 14 at a distance of ∼6 km from the surface. Several images
  covering the 0°-33° phase angle range were acquired, and the spatial
  resolution achieved was 11 cm pixel<SUP>-1</SUP>. The flown-by region
  is located on the big lobe of the comet, near the borders of the Ash,
  Apis and Imhotep regions. Our analysis shows that this region features
  local heterogeneities at the decimetre scale. We observed difference
  of reflectance up to 40 per cent between bright spots and sombre
  regions, and spectral slope variations up to 50 per cent. The spectral
  reddening effect observed globally on the comet surface by Fornasier
  et al. (2015) is also observed locally on this region, but with a
  less steep behaviour. We note that numerous metre-sized boulders,
  which exhibit a smaller opposition effect, also appear spectrally
  redder than their surroundings. In this region, we found no evidence
  linking observed bright spots to exposed water-ice-rich material. We
  fitted our data set using the Hapke 2008 photometric model. The region
  overflown is globally as dark as the whole nucleus (geometric albedo of
  6.8 per cent) and it has a high porosity value in the uppermost layers
  (86 per cent). These results of the photometric analysis at a decimetre
  scale indicate that the photometric properties of the flown-by region
  are similar to those previously found for the whole nucleus.

---------------------------------------------------------
Title: Geologic mapping of the Comet 67P/Churyumov-Gerasimenko's
    Northern hemisphere
Authors: Giacomini, L.; Massironi, M.; El-Maarry, M. R.; Penasa,
   L.; Pajola, M.; Thomas, N.; Lowry, S. C.; Barbieri, C.; Cremonese,
   G.; Ferri, F.; Naletto, G.; Bertini, I.; La Forgia, F.; Lazzarin,
   M.; Marzari, F.; Sierks, H.; Lamy, P. L.; Rodrigo, R.; Rickman,
   H.; Koschny, D.; Keller, H. U.; Agarwal, J.; A'Hearn, M. F.; Auger,
   A. -T.; Barucci, M. A.; Bertaux, J. -L.; Besse, S.; Bodewits, D.;
   Da Deppo, V.; Davidsson, B.; De Cecco, M.; Debei, S.; Fornasier, S.;
   Fulle, M.; Groussin, O.; Gutierrez, P. J.; Güttler, C.; Hviid, S. F.;
   Ip, W. -H.; Jorda, L.; Knollenberg, J.; Kovacs, G.; Kramm, J. -R.;
   Kührt, E.; Küppers, M.; Lara, L. M.; Moreno, J. J. Lopez; Magrin,
   S.; Michalik, H.; Oklay, N.; Pommerol, A.; Preusker, F.; Scholten,
   F.; Tubiana, C.; Vincent, J. -B.
2016MNRAS.462S.352G    Altcode:
  The Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS),
  the scientific imaging system onboard the Rosetta mission, has been
  acquiring images of the nucleus of the comet 67P/Churyumov-Gerasimenko
  since 2014 August with a resolution which allows a detailed analysis
  of its surface. Indeed, data reveal a complex surface morphology
  which is likely the expression of different processes which occurred
  at different times on the cometary nucleus. In order to characterize
  these different morphologies and better understand their distribution,
  we performed a geologic mapping of comet's 67P Northern hemisphere in
  which features have been distinguished based on their morphological,
  textural and stratigraphic characteristics. For this purpose, we used
  narrow-angle camera images acquired in 2014 August and September with
  a spatial scale ranging from 1.2 to 2.4 m pixel<SUP>-1</SUP>. Several
  different geologic units have been identified on the basis of their
  different surface textures, granulometry and morphology. Some of these
  units are distinctive and localized, whereas others are more common
  and distributed all over the Northern hemisphere. Moreover, different
  types of linear features have been distinguished on the basis of their
  morphology. Some of these lineaments have never been observed before
  on a comet and can offer important clues on the internal structures
  of the nucleus itself. The geologic mapping results presented here
  will allow us to better understand the processes which affected the
  nucleus' surface and thus the origin and evolutionary history of comet
  67P/Churyumov-Gerasimenko.

---------------------------------------------------------
Title: The 2016 Feb 19 outburst of comet 67P/CG: an ESA Rosetta
    multi-instrument study
Authors: Grün, E.; Agarwal, J.; Altobelli, N.; Altwegg, K.;
   Bentley, M. S.; Biver, N.; Della Corte, V.; Edberg, N.; Feldman,
   P. D.; Galand, M.; Geiger, B.; Götz, C.; Grieger, B.; Güttler, C.;
   Henri, P.; Hofstadter, M.; Horanyi, M.; Jehin, E.; Krüger, H.; Lee,
   S.; Mannel, T.; Morales, E.; Mousis, O.; Müller, M.; Opitom, C.;
   Rotundi, A.; Schmied, R.; Schmidt, F.; Sierks, H.; Snodgrass, C.;
   Soja, R. H.; Sommer, M.; Srama, R.; Tzou, C. -Y.; Vincent, J. -B.;
   Yanamandra-Fisher, P.; A'Hearn, M. F.; Erikson, A. I.; Barbieri, C.;
   Barucci, M. A.; Bertaux, J. -L.; Bertini, I.; Burch, J.; Colangeli,
   L.; Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco,
   M.; Deller, J.; Feaga, L. M.; Ferrari, M.; Fornasier, S.; Fulle,
   M.; Gicquel, A.; Gillon, M.; Green, S. F.; Groussin, O.; Gutiérrez,
   P. J.; Hofmann, M.; Hviid, S. F.; Ip, W. -H.; Ivanovski, S.; Jorda,
   L.; Keller, H. U.; Knight, M. M.; Knollenberg, J.; Koschny, D.; Kramm,
   J. -R.; Kührt, E.; Küppers, M.; Lamy, P. L.; Lara, L. M.; Lazzarin,
   M.; Lòpez-Moreno, J. J.; Manfroid, J.; Epifani, E. Mazzotta; Marzari,
   F.; Naletto, G.; Oklay, N.; Palumbo, P.; Parker, J. Wm.; Rickman,
   H.; Rodrigo, R.; Rodrìguez, J.; Schindhelm, R.; Shi, X.; Sordini,
   R.; Steffl, A. J.; Stern, S. A.; Thomas, N.; Tubiana, C.; Weaver,
   H. A.; Weissman, P.; Zakharov, V. V.; Taylor, M. G. G. T.
2016MNRAS.462S.220G    Altcode: 2016MNRAS.tmp.1212G
  On 2016 Feb 19, nine Rosetta instruments serendipitously
  observed an outburst of gas and dust from the nucleus of comet
  67P/Churyumov-Gerasimenko. Among these instruments were cameras and
  spectrometers ranging from UV over visible to microwave wavelengths,
  in situ gas, dust and plasma instruments, and one dust collector. At
  09:40 a dust cloud developed at the edge of an image in the shadowed
  region of the nucleus. Over the next two hours the instruments
  recorded a signature of the outburst that significantly exceeded the
  background. The enhancement ranged from 50 per cent of the neutral gas
  density at Rosetta to factors &gt;100 of the brightness of the coma
  near the nucleus. Dust related phenomena (dust counts or brightness
  due to illuminated dust) showed the strongest enhancements (factors
  &gt;10). However, even the electron density at Rosetta increased by
  a factor 3 and consequently the spacecraft potential changed from
  ∼-16 V to -20 V during the outburst. A clear sequence of events
  was observed at the distance of Rosetta (34 km from the nucleus):
  within 15 min the Star Tracker camera detected fast particles (∼25
  m s<SUP>-1</SUP>) while 100 μm radius particles were detected by the
  GIADA dust instrument ∼1 h later at a speed of 6 m s<SUP>-1</SUP>. The
  slowest were individual mm to cm sized grains observed by the OSIRIS
  cameras. Although the outburst originated just outside the FOV of the
  instruments, the source region and the magnitude of the outburst could
  be determined.

---------------------------------------------------------
Title: Detection of exposed H<SUB>2</SUB>O ice on the nucleus of
    comet 67P/Churyumov-Gerasimenko. as observed by Rosetta OSIRIS and
    VIRTIS instruments
Authors: Barucci, M. A.; Filacchione, G.; Fornasier, S.; Raponi, A.;
   Deshapriya, J. D. P.; Tosi, F.; Feller, C.; Ciarniello, M.; Sierks,
   H.; Capaccioni, F.; Pommerol, A.; Massironi, M.; Oklay, N.; Merlin,
   F.; Vincent, J. -B.; Fulchignoni, M.; Guilbert-Lepoutre, A.; Perna,
   D.; Capria, M. T.; Hasselmann, P. H.; Rousseau, B.; Barbieri, C.;
   Bockelée-Morvan, D.; Lamy, P. L.; De Sanctis, C.; Rodrigo, R.; Erard,
   S.; Koschny, D.; Leyrat, C.; Rickman, H.; Drossart, P.; Keller, H. U.;
   A'Hearn, M. F.; Arnold, G.; Bertaux, J. -L.; Bertini, I.; Cerroni, P.;
   Cremonese, G.; Da Deppo, V.; Davidsson, B. J. R.; El-Maarry, M. R.;
   Fonti, S.; Fulle, M.; Groussin, O.; Güttler, C.; Hviid, S. F.; Ip,
   W.; Jorda, L.; Kappel, D.; Knollenberg, J.; Kramm, J. -R.; Kührt, E.;
   Küppers, M.; Lara, L.; Lazzarin, M.; Lopez Moreno, J. J.; Mancarella,
   F.; Marzari, F.; Mottola, S.; Naletto, G.; Pajola, M.; Palomba, E.;
   Quirico, E.; Schmitt, B.; Thomas, N.; Tubiana, C.
2016A&A...595A.102B    Altcode: 2016arXiv160900551B
  Context. Since the orbital insertion of the Rosetta spacecraft,
  comet 67P/Churyumov-Gerasimenko (67P) has been mapped by OSIRIS
  camera and VIRTIS spectro-imager, producing a huge quantity of images
  and spectra of the comet's nucleus. <BR /> Aims: The aim of this
  work is to search for the presence of H<SUB>2</SUB>O on the nucleus
  which, in general, appears very dark and rich in dehydrated organic
  material. After selecting images of the bright spots which could be good
  candidates to search for H<SUB>2</SUB>O ice, taken at high resolution
  by OSIRIS, we check for spectral cubes of the selected coordinates to
  identify these spots observed by VIRTIS. <BR /> Methods: The selected
  OSIRIS images were processed with the OSIRIS standard pipeline and
  corrected for the illumination conditions for each pixel using the
  Lommel-Seeliger disk law. The spots with higher I/F were selected and
  then analysed spectrophotometrically and compared with the surrounding
  area. We selected 13 spots as good targets to be analysed by VIRTIS
  to search for the 2 μm absorption band of water ice in the VIRTIS
  spectral cubes. <BR /> Results: Out of the 13 selected bright spots,
  eight of them present positive H<SUB>2</SUB>O ice detection on the
  VIRTIS data. A spectral analysis was performed and the approximate
  temperature of each spot was computed. The H<SUB>2</SUB>O ice content
  was confirmed by modeling the spectra with mixing (areal and intimate)
  of H<SUB>2</SUB>O ice and dark terrain, using Hapke's radiative transfer
  modeling. We also present a detailed analysis of the detected spots.

---------------------------------------------------------
Title: Geomorphological mapping of comet 67P/Churyumov-Gerasimenko's
    Southern hemisphere
Authors: Lee, Jui-Chi; Massironi, Matteo; Ip, Wing-Huen; Giacomini,
   Lorenza; Ferrari, Sabrina; Penasa, Luca; El-Maarry, Mohamed Ramy;
   Pajola, Maurizio; Lai, Ian-Lin; Lin, Zhong-Yi; Ferri, Francesca;
   Sierks, Holger; Barbieri, Cesare; Lamy, Philippe; Rodrigo, Rafael;
   Koschny, Detlef; Rickman, Hans; Keller, Horst Uwe; Agarwal, Jessica;
   A'Hearn, Michael F.; Barucci, Maria Antonella; Bertaux, Jean-Loup;
   Bertini, Ivano; Cremonese, Gabriele; Da Deppo, Vania; Davidsson,
   Björn; Debei, Stefano; De Cecco, Mariolino; Deller, Jakob; Fornasier,
   Sonia; Fulle, Marco; Groussin, Olivier; Gutiérrez, Pedro J.; Güttler,
   Carsten; Hofmann, Marc; Hviid, Stubbe F.; Jorda, Laurent; Knollenberg,
   Jörg; Kovacs, Gabor; Kramm, J. -Rainer; Kührt, Ekkehard; Küppers,
   Michael; Lara, Luisa M.; Lazzarin, Monica; Marzari, Francesco; Lopez
   Moreno, Josè J.; Naletto, Giampiero; Oklay, Nilda; Shi, Xian; Thomas,
   Nicolas; Tubiana, Cecilia; Vincent, Jean-Baptiste
2016MNRAS.462S.573L    Altcode:
  In 2015 May, the Southern hemisphere of comet 67P/Churyumov-Gerasimenko
  became visible by the OSIRIS cameras on-board the Rosetta
  spacecraft. The resolution was high enough to carry out a detailed
  analysis of the surface morphology, which is quite different from the
  Northern hemisphere. Previous works show that fine particle deposits
  are the most extensive geological unit in the Northern hemisphere. In
  contrast, the Southern hemisphere is dominated by outcropping
  consolidated terrain. In this work, we provide geomorphological maps
  of the Southern hemisphere with the distinction of both geological
  units and linear features. The geomorphological maps described in this
  study allow us to gain a better understanding of the processes shaping
  the comet nucleus and the distribution of primary structures such as
  fractures and strata.

---------------------------------------------------------
Title: Sublimation of icy aggregates in the coma of comet
    67P/Churyumov-Gerasimenko detected with the OSIRIS cameras on
    board Rosetta
Authors: Gicquel, A.; Vincent, J. -B.; Agarwal, J.; A'Hearn, M. F.;
   Bertini, I.; Bodewits, D.; Sierks, H.; Lin, Z. -Y.; Barbieri, C.;
   Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller, H. U.;
   Barucci, M. A.; Bertaux, J. -L.; Besse, S.; Cremonese, G.; Da Deppo,
   V.; Davidsson, B.; Debei, S.; Deller, J.; De Cecco, M.; Frattin, E.;
   El-Maarry, M. R.; Fornasier, S.; Fulle, M.; Groussin, O.; Gutiérrez,
   P. J.; Gutiérrez-Marquez, P.; Güttler, C.; Höfner, S.; Hofmann,
   M.; Hu, X.; Hviid, S. F.; Ip, W. -H.; Jorda, L.; Knollenberg, J.;
   Kovacs, G.; Kramm, J. -R.; Kührt, E.; Küppers, M.; Lara, L. M.;
   Lazzarin, M.; Moreno, J. J. Lopez; Lowry, S.; Marzari, F.; Masoumzadeh,
   N.; Massironi, M.; Moreno, F.; Mottola, S.; Naletto, G.; Oklay, N.;
   Pajola, M.; Pommerol, A.; Preusker, F.; Scholten, F.; Shi, X.; Thomas,
   N.; Toth, I.; Tubiana, C.
2016MNRAS.462S..57G    Altcode: 2016arXiv160808774G; 2016MNRAS.tmp.1233G
  Beginning in 2014 March, the OSIRIS (Optical, Spectroscopic, and
  Infrared Remote Imaging System) cameras began capturing images of the
  nucleus and coma (gas and dust) of comet 67P/Churyumov-Gerasimenko
  using both the wide angle camera (WAC) and the narrow angle camera
  (NAC). The many observations taken since July of 2014 have been used to
  study the morphology, location, and temporal variation of the comet's
  dust jets. We analysed the dust monitoring observations shortly after
  the southern vernal equinox on 2015 May 30 and 31 with the WAC at the
  heliocentric distance R<SUB>h</SUB> = 1.53 AU, where it is possible
  to observe that the jet rotates with the nucleus. We found that the
  decline of brightness as a function of the distance of the jet is
  much steeper than the background coma, which is a first indication of
  sublimation. We adapted a model of sublimation of icy aggregates and
  studied the effect as a function of the physical properties of the
  aggregates (composition and size). The major finding of this paper
  was that through the sublimation of the aggregates of dirty grains
  (radius a between 5 and 50 μm) we were able to completely reproduce
  the radial brightness profile of a jet beyond 4 km from the nucleus. To
  reproduce the data, we needed to inject a number of aggregates between
  8.5 × 10<SUP>13</SUP> and 8.5 × 10<SUP>10</SUP> for a = 5 and 50 μm,
  respectively, or an initial mass of H<SUB>2</SUB>O ice around 22 kg.

---------------------------------------------------------
Title: 67P/C-G inner coma dust properties from 2.2 au inbound to
    2.0 au outbound to the Sun
Authors: Della Corte, V.; Rotundi, A.; Fulle, M.; Ivanovski, S.; Green,
   S. F.; Rietmeijer, F. J. M.; Colangeli, L.; Palumbo, P.; Sordini, R.;
   Ferrari, M.; Accolla, M.; Zakharov, V.; Mazzotta Epifani, E.; Weissman,
   P.; Gruen, E.; Lopez-Moreno, J. J.; Rodriguez, J.; Bussoletti, E.;
   Crifo, J. F.; Esposito, F.; Lamy, P. L.; McDonnell, J. A. M.; Mennella,
   V.; Molina, A.; Morales, R.; Moreno, F.; Palomba, E.; Perrin, J. M.;
   Rodrigo, R.; Zarnecki, J. C.; Cosi, M.; Giovane, F.; Gustafson, B.;
   Ortiz, J. L.; Jeronimo, J. M.; Leese, M. R.; Herranz, M.; Liuzzi,
   V.; Lopez-Jimenez, A. C.
2016MNRAS.462S.210D    Altcode: 2016MNRAS.tmp.1514D
  GIADA (Grain Impact Analyzer and Dust Accumulator) on-board the
  Rosetta space probe is designed to measure the momentum, mass and
  speed of individual dust particles escaping the nucleus of comet
  67P/Churyumov-Gerasimenko (hereafter 67P). From 2014 August to
  2016 June, Rosetta escorted comet 67P during its journey around
  the Sun. Here, we focus on GIADA data taken between 2015 January
  and 2016 February which included 67P's perihelion passage. To better
  understand cometary activity and more specifically the presence of dust
  structures in cometary comae, we mapped the spatial distribution of dust
  density in 67P's coma. In this manner, we could track the evolution of
  high-density regions of coma dust and their connections with nucleus
  illumination conditions, namely tracking 67P's seasons. We also studied
  the link between dust particle speeds and their masses with respect to
  heliocentric distance, I.e. the level of cometary activity. This allowed
  us to derive a global and a local correlation of the dust particles'
  speed distribution with respect to the H<SUB>2</SUB>O production rate.

---------------------------------------------------------
Title: Modelling of the outburst on July 29<SUP>th</SUP> ,
    2015 observed with OSIRIS in the southern hemisphere of comet
    67P/Churyumov-Gerasimenko
Authors: Gicquel, Adeline; Vincent, Jean-Baptiste; Sierks, Holger;
   Rose, Martin; Agarwal, Jessica; Deller, Jakob; Guettler, Carsten;
   Hoefner, Sebastian; Hofmann, Marc; Hu, Xuanyu; Kovacs, Gabor; Oklay
   Vincent, Nilda; Shi, Xian; Tubiana, Cecilia; Barbieri, Cesare; Lamy,
   Phylippe; Rodrigo, Rafael; Koschny, Detlef; Rickman, Hans; OSIRIS Team
2016DPS....4811614G    Altcode:
  Images of the nucleus and the coma (gas and dust) of comet
  67P/Churyumov- Gerasimenko have been acquired by the OSIRIS (Optical,
  Spectroscopic, and Infrared Remote Imaging System) cameras system since
  March 2014 using both the wide angle camera (WAC) and the narrow angle
  camera (NAC). We are using the NAC camera to study the bright outburst
  observed on July 29<SUP>th</SUP>, 2015 in the southern hemisphere. The
  NAC camera's wavelength ranges between 250-1000 nm with a combination
  of 12 filters. The high spatial resolution is needed to localize the
  source point of the outburst on the surface of the nucleus. At the
  time of the observations, the heliocentric distance was 1.25AU and the
  distance between the spacecraft and the comet was 126 km. We aim to
  understand the physics leading to such outgassing: Is the jet associated
  to the outbursts controlled by the micro-topography? Or by ice suddenly
  exposed? We are using the Direct Simulation Monte Carlo (DSMC) method
  to study the gas flow close to the nucleus. The goal of the DSMC code is
  to reproduce the opening angle of the jet, and constrain the outgassing
  ratio between outburst source and local region. The results of this
  model will be compared to the images obtained with the NAC camera.

---------------------------------------------------------
Title: Comet 67P as seen by Rosetta/OSIRIS
Authors: Guettler, Carsten; Sierks, Holger; Barbieri, Cesare;
   Lamy, Philippe L.; Rodrigo, Rafael; Koschny, Detlef; Rickman, Hans;
   OSIRIS Team
2016DPS....4820102G    Altcode:
  In September 2016, the ESA Rosetta mission will come to its
  ending. Having escorted comet 67P for more than two years, the
  scientific camera system OSIRIS onboard Rosetta witnessed all important
  milestones of the mission: after the first characterization and the
  Philae landing we saw the comet's activity increasing while it was
  approaching the Sun. During the peak of activity around perihel in
  August 2015, the spacecraft had to retreat to a safe distance but
  we witnessed strong but predictable jet activity and, at the same
  time, short lived eruptions, some of these being big outbursts. When
  the activity declined post perihelion and allowed the spacecraft
  to go back closer, comparison with the early characterization
  revealed numerous morphologic changes on the surface, which can
  be attributed to the strong activity during perihelion passage.The
  paper will give an overview of latest OSIRIS science and discoveries
  including the morphology, activity, and surface changes mentioned
  above. Implications on the nature of the comet and its mechanisms
  will be drawn from these. The current plan for the mission is to go to
  very close distances in August and September 2016 and finally land the
  spacecraft on 67P.Acknowledgements: OSIRIS was built by a consortium
  led by the Max-Planck-Institut für Sonnensystemforschung, Göttingen,
  Germany, in collaboration with CISAS, University of Padova, Italy,
  the Laboratoire d'Astrophysique de Marseille, France, the Instituto
  de Astrofísica de Andalucia, CSIC, Granada, Spain, the Scientific
  Support Office of the European Space Agency, Noordwijk, The Netherlands,
  the Instituto Nacional de Técnica Aeroespacial, Madrid, Spain, the
  Universidad Politéchnica de Madrid, Spain, the Department of Physics
  and Astronomy of Uppsala University, Sweden, and the Institut für
  Datentechnik und Kommunikationsnetze der Technischen Universität
  Braunschweig, Germany.We thank the Rosetta Science Ground Segment at
  ESAC, the Rosetta Mission Operations Centre at ESOC and the Rosetta
  Project at ESTEC for their outstanding work enabling the science return
  of the Rosetta Mission.

---------------------------------------------------------
Title: The global shape, density and rotation of Comet
    67P/Churyumov-Gerasimenko from preperihelion Rosetta/OSIRIS
    observations
Authors: Jorda, L.; Gaskell, R.; Capanna, C.; Hviid, S.; Lamy, P.;
   Ďurech, J.; Faury, G.; Groussin, O.; Gutiérrez, P.; Jackman, C.;
   Keihm, S. J.; Keller, H. U.; Knollenberg, J.; Kührt, E.; Marchi, S.;
   Mottola, S.; Palmer, E.; Schloerb, F. P.; Sierks, H.; Vincent, J. -B.;
   A'Hearn, M. F.; Barbieri, C.; Rodrigo, R.; Koschny, D.; Rickman, H.;
   Barucci, M. A.; Bertaux, J. L.; Bertini, I.; Cremonese, G.; Da Deppo,
   V.; Davidsson, B.; Debei, S.; De Cecco, M.; Fornasier, S.; Fulle, M.;
   Güttler, C.; Ip, W. -H.; Kramm, J. R.; Küppers, M.; Lara, L. M.;
   Lazzarin, M.; Lopez Moreno, J. J.; Marzari, F.; Naletto, G.; Oklay,
   N.; Thomas, N.; Tubiana, C.; Wenzel, K. -P.
2016Icar..277..257J    Altcode:
  The Rosetta spacecraft reached Comet 67P/Churyumov-Gerasimenko
  (hereafter 67P/C-G) in August 2014 at an heliocentric distance of 3.6
  a.u. and was then put in orbit around its nucleus to perform detailed
  observations. Among the collected data are the images acquired by
  the OSIRIS instrument up to the perihelion passage of the comet in
  August 2015, which allowed us to map the entire nucleus surface at
  high-resolution in the visible. Stereophotoclinometry methods have been
  used to reconstruct a global high-resolution shape model and to monitor
  its rotational parameters using data collected up to perihelion. <P
  />The nucleus has a conspicuous bilobate shape with overall dimensions
  along its principal axes of (4.34 ± 0.02) × (2.60 ± 0.02) × (2.12
  ± 0.06) km. The best-fit ellipsoid dimensions of the individual lobes
  along their principal axes of inertia are found to be 4.10 × 3.52 ×
  1.63 km and 2.50 × 2.14 × 1.64 km. Their volume amounts to 66% and
  27% of the total volume of the nucleus. The two lobes are connected
  by a "neck" whose volume has been estimated to represent ∼7% of the
  total volume of the comet. Combining the derived volume of 18.8 ±
  0.3 km<SUP>3</SUP> with the mass of 9.982 ± 0.003 × 10<SUP>12</SUP>
  kg determined by the Rosetta/RSI experiment, we obtained a bulk
  density of the nucleus of 532 ± 7 kg m<SUP>-3</SUP> . Together with
  the companion value of 535 ± 35 kg m<SUP>-3</SUP> deduced from the
  stereophotogrammetry shape model of the nucleus (Preusker et al. [2015]
  Astron. Astrophys. 583, A33), these constitute the first reliable and
  most accurate determination of the density of a cometary nucleus to
  date. The calculated porosity is quite large, ranging approximately
  from 70% to 75% depending upon the assumed density of the dust
  grains and the dust-to-ice mass ratio. The nature of the porosity,
  either micro or macro or both, remains unconstrained. The coordinates
  of the center of gravity are not compatible with a uniform nucleus
  density. The direction of the offset between the center of gravity and
  the center of figure suggests that the big lobe has a slightly higher
  bulk density compared to the small one. the center of mass position
  cannot be explained by different, but homogenous densities in the two
  lobes. <P />The initial rotational period of 12.4041 ± 0.0001 h of
  the nucleus persisted until October 2014. It then slightly increased
  to a maximum of 12.4304 h reached on 19 May 2015 and finally dropped
  to 12.305 h just before perihelion on August 10, 2015. A periodogram
  analysis of the (RA, Dec) direction of the Z-axis of the comet obtained
  in parallel with the shape reconstruction exhibits a highly significant
  minima at 11.5 ± 0.5 day clearly indicating an excited rotational
  state with an amplitude of 0.15 ± 0.03°.

---------------------------------------------------------
Title: Reconstruction of the Abydos ROSETTA/Philae landing site at
    very high spatial resolution
Authors: Capanna, Claire; Jorda, Laurent; Lamy, Philippe L.; Gaskell,
   Robert W.; FAURY, Guillaume; DELMAS, Cédric; DURAND, Joelle; GAUDON,
   Philippe; GARMIER, Romain; JURADO, Eric; OSIRIS Team
2016DPS....4811006C    Altcode:
  The Rosetta/Philae module landed in a very uneven area called
  Abydos. The landing site has beenidentified on images of this region
  acquired by the OSIRIS imaging system aboard the orbiterbefore
  (Oct. 2014) and after (Dec. 2014) the landing (Lamy et al., in
  prep.).Abydos exhibits a complex topography including numerous cliffs,
  several overhangs and lots ofboulders (Lucchetti et al. A&amp;A 585,
  L1, 2016). This makes its reconstruction a challenging taskfor 3D
  reconstruction techniques.We use a very carefully selected set of
  high-resolution OSIRIS images acquired betweenMarch 2016 and August 2016
  to reconstruct the detailed topography of the Abydos neighborhoodusing a
  method called “multiresolution photoclinometry by deformation” (MPCD,
  Capanna et al.,The Visual Computer, 29(6-8): 825-835, 2013). We also
  check the compatibility of the local DTMcomparing the panoramic images
  obtained by the CIVA-P instrument aboard PHILAE with syntheticimages
  created with the DTM, and we compute the distances, incidence and
  emission angles duringthe acquisition of these images.

---------------------------------------------------------
Title: Time-dependent tomographic reconstruction of the solar corona
Authors: Vibert, D.; Peillon, C.; Lamy, P.; Frazin, R. A.; Wojak, J.
2016A&C....17..144V    Altcode: 2016arXiv160706308V
  Solar rotational tomography (SRT) applied to white-light coronal
  images observed at multiple aspect angles has been the preferred
  approach for determining the three-dimensional (3D) electron density
  structure of the solar corona. However, it is seriously hampered by
  the restrictive assumption that the corona is time-invariant which
  introduces significant errors in the reconstruction. We first explore
  several methods to mitigate the temporal variation of the corona by
  decoupling the "fast-varying" inner corona from the "slow-moving" outer
  corona using multiple masking (either by juxtaposition or recursive
  combination) and radial weighting. Weighting with a radial exponential
  profile provides some improvement over a classical reconstruction but
  only beyond ≈ 3R<SUB>⊙</SUB>. We next consider a full time-dependent
  tomographic reconstruction involving spatio-temporal regularization
  and further introduce a co-rotating regularization aimed at preventing
  concentration of reconstructed density in the plane of the sky. Crucial
  to testing our procedure and properly tuning the regularization
  parameters is the introduction of a time-dependent MHD model of
  the corona based on observed magnetograms to build a time-series of
  synthetic images of the corona. Our procedure, which successfully
  reproduces the time-varying model corona, is finally applied to a set
  of 53 LASCO-C2 pB images roughly evenly spaced in time from 15 to 29
  March 2009. Our procedure paves the way to a time-dependent tomographic
  reconstruction of the coronal electron density to the whole set of
  LASCO-C2 images presently spanning 20 years.

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Title: Regional surface morphology of comet 67P/Churyumov-Gerasimenko
from Rosetta/OSIRIS images: The southern hemisphere
Authors: El-Maarry, M. R.; Thomas, N.; Gracia-Berná, A.; Pajola,
   M.; Lee, J. -C.; Massironi, M.; Davidsson, B.; Marchi, S.; Keller,
   H. U.; Hviid, S. F.; Besse, S.; Sierks, H.; Barbieri, C.; Lamy,
   P. L.; Koschny, D.; Rickman, H.; Rodrigo, R.; A'Hearn, M. F.; Auger,
   A. -T.; Barucci, M. A.; Bertaux, J. -L.; Bertini, I.; Bodewits, D.;
   Cremonese, G.; Da Deppo, V.; De Cecco, M.; Debei, S.; Güttler, C.;
   Fornasier, S.; Fulle, M.; Giacomini, L.; Groussin, O.; Gutierrez,
   P. J.; Ip, W. -H.; Jorda, L.; Knollenberg, J.; Kovacs, G.; Kramm,
   J. -R.; Kührt, E.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Lopez
   Moreno, J. J.; Marschall, R.; Marzari, F.; Naletto, G.; Oklay, N.;
   Pommerol, A.; Preusker, F.; Scholten, F.; Tubiana, C.; Vincent, J. -B.
2016A&A...593A.110E    Altcode:
  <BR /> Aims: The OSIRIS camera on board the Rosetta spacecraft has
  been acquiring images of the comet 67P/Churyumov-Gerasimenko (67P)'s
  nucleus since August 2014. Starting in May 2015, the southern hemisphere
  gradually became illuminated and was imaged for the first time. Here
  we present the regional morphology of the southern hemisphere,
  which serves as a companion to an earlier paper that presented the
  regional morphology of the northern hemisphere. <BR /> Methods: We used
  OSIRIS images that were acquired at orbits ~45-125 km from the center
  of the comet (corresponding to spatial resolutions of ~0.8 to 2.3
  m/pixel) coupled with the use of digital terrain models to define the
  different regions on the surface, and identify structural boundaries
  accurately. <BR /> Results: Seven regions have been defined in the
  southern hemisphere bringing the total number of defined regions on the
  surface of the nucleus to 26. These classifications are mainly based on
  morphological and/or topographic boundaries. The southern hemisphere
  shows a remarkable dichotomy with its northern counterpart mainly
  because of the absence of wide-scale smooth terrains, dust coatings and
  large unambiguous depressions. As a result, the southern hemisphere
  closely resembles previously identified consolidated regions. An
  assessment of the overall morphology of comet 67P suggests that the
  comet's two lobes show surface heterogeneities manifested in different
  physical/mechanical characteristics, possibly extending to local (I.e.,
  within a single region) scales.

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Title: A small mission concept to the Sun-Earth Lagrangian L5 point
    for innovative solar, heliospheric and space weather science
Authors: Lavraud, B.; Liu, Y.; Segura, K.; He, J.; Qin, G.; Temmer,
   M.; Vial, J. -C.; Xiong, M.; Davies, J. A.; Rouillard, A. P.; Pinto,
   R.; Auchère, F.; Harrison, R. A.; Eyles, C.; Gan, W.; Lamy, P.;
   Xia, L.; Eastwood, J. P.; Kong, L.; Wang, J.; Wimmer-Schweingruber,
   R. F.; Zhang, S.; Zong, Q.; Soucek, J.; An, J.; Prech, L.; Zhang,
   A.; Rochus, P.; Bothmer, V.; Janvier, M.; Maksimovic, M.; Escoubet,
   C. P.; Kilpua, E. K. J.; Tappin, J.; Vainio, R.; Poedts, S.; Dunlop,
   M. W.; Savani, N.; Gopalswamy, N.; Bale, S. D.; Li, G.; Howard, T.;
   DeForest, C.; Webb, D.; Lugaz, N.; Fuselier, S. A.; Dalmasse, K.;
   Tallineau, J.; Vranken, D.; Fernández, J. G.
2016JASTP.146..171L    Altcode:
  We present a concept for a small mission to the Sun-Earth Lagrangian L5
  point for innovative solar, heliospheric and space weather science. The
  proposed INvestigation of Solar-Terrestrial Activity aNd Transients
  (INSTANT) mission is designed to identify how solar coronal magnetic
  fields drive eruptions, mass transport and particle acceleration that
  impact the Earth and the heliosphere. INSTANT is the first mission
  designed to (1) obtain measurements of coronal magnetic fields from
  space and (2) determine coronal mass ejection (CME) kinematics with
  unparalleled accuracy. Thanks to innovative instrumentation at a vantage
  point that provides the most suitable perspective view of the Sun-Earth
  system, INSTANT would uniquely track the whole chain of fundamental
  processes driving space weather at Earth. We present the science
  requirements, payload and mission profile that fulfill ambitious science
  objectives within small mission programmatic boundary conditions.

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Title: The primordial nucleus of comet 67P/Churyumov-Gerasimenko
Authors: Davidsson, B. J. R.; Sierks, H.; Güttler, C.; Marzari, F.;
   Pajola, M.; Rickman, H.; A'Hearn, M. F.; Auger, A. -T.; El-Maarry,
   M. R.; Fornasier, S.; Gutiérrez, P. J.; Keller, H. U.; Massironi, M.;
   Snodgrass, C.; Vincent, J. -B.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.;
   Koschny, D.; Barucci, M. A.; Bertaux, J. -L.; Bertini, I.; Cremonese,
   G.; Da Deppo, V.; Debei, S.; De Cecco, M.; Feller, C.; Fulle, M.;
   Groussin, O.; Hviid, S. F.; Höfner, S.; Ip, W. -H.; Jorda, L.;
   Knollenberg, J.; Kovacs, G.; Kramm, J. -R.; Kührt, E.; Küppers,
   M.; La Forgia, F.; Lara, L. M.; Lazzarin, M.; Lopez Moreno, J. J.;
   Moissl-Fraund, R.; Mottola, S.; Naletto, G.; Oklay, N.; Thomas, N.;
   Tubiana, C.
2016A&A...592A..63D    Altcode:
  Context. We investigate the formation and evolution of comet nuclei
  and other trans-Neptunian objects (TNOs) in the solar nebula and
  primordial disk prior to the giant planet orbit instability foreseen
  by the Nice model. <BR /> Aims: Our goal is to determine whether most
  observed comet nuclei are primordial rubble-pile survivors that formed
  in the solar nebula and young primordial disk or collisional rubble
  piles formed later in the aftermath of catastrophic disruptions of
  larger parent bodies. We also propose a concurrent comet and TNO
  formation scenario that is consistent with observations. <BR />
  Methods: We used observations of comet 67P/Churyumov-Gerasimenko by
  the ESA Rosetta spacecraft, particularly by the OSIRIS camera system,
  combined with data from the NASA Stardust sample-return mission to comet
  81P/Wild 2 and from meteoritics; we also used existing observations
  from ground or from spacecraft of irregular satellites of the giant
  planets, Centaurs, and TNOs. We performed modeling of thermophysics,
  hydrostatics, orbit evolution, and collision physics. <BR /> Results:
  We find that thermal processing due to short-lived radionuclides,
  combined with collisional processing during accretion in the primordial
  disk, creates a population of medium-sized bodies that are comparably
  dense, compacted, strong, heavily depleted in supervolatiles like CO
  and CO<SUB>2</SUB>; they contain little to no amorphous water ice,
  and have experienced extensive metasomatism and aqueous alteration due
  to liquid water. Irregular satellites Phoebe and Himalia are potential
  representatives of this population. Collisional rubble piles inherit
  these properties from their parents. Contrarily, comet nuclei have low
  density, high porosity, weak strength, are rich in supervolatiles, may
  contain amorphous water ice, and do not display convincing evidence of
  in situ metasomatism or aqueous alteration. We outline a comet formation
  scenario that starts in the solar nebula and ends in the primordial
  disk, that reproduces these observed properties, and additionally
  explains the presence of extensive layering on 67P/Churyumov-Gerasimenko
  (and on 9P/Tempel 1 observed by Deep Impact), its bi-lobed shape,
  the extremely slow growth of comet nuclei as evidenced by recent
  radiometric dating, and the low collision probability that allows
  primordial nuclei to survive the age of the solar system. <BR />
  Conclusions: We conclude that observed comet nuclei are primordial
  rubble piles, and not collisional rubble piles. We argue that TNOs
  formed as a result of streaming instabilities at sizes below ~400 km
  and that ~350 of these grew slowly in a low-mass primordial disk to
  the size of Triton, Pluto, and Eris, causing little viscous stirring
  during growth. We thus propose a dynamically cold primordial disk,
  which prevented medium-sized TNOs from breaking into collisional rubble
  piles and allowed the survival of primordial rubble-pile comets. We
  argue that comets formed by hierarchical agglomeration out of material
  that remained after TNO formation, and that this slow growth was a
  necessity to avoid thermal processing by short-lived radionuclides
  that would lead to loss of supervolatiles, and that allowed comet
  nuclei to incorporate ~3 Myr old material from the inner solar system.

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Title: The southern hemisphere of 67P/Churyumov-Gerasimenko: Analysis
    of the preperihelion size-frequency distribution of boulders ≥7 m
Authors: Pajola, Maurizio; Lucchetti, Alice; Vincent, Jean-Baptiste;
   Oklay, Nilda; El-Maarry, Mohamed R.; Bertini, Ivano; Naletto,
   Giampiero; Lazzarin, Monica; Massironi, Matteo; Sierks, Holger;
   Barbieri, Cesare; Lamy, Philippe; Rodrigo, Rafael; Koschny, Detlef;
   Rickman, Hans; Keller, Horst U.; Agarwal, Jessica; A'Hearn, Michael F.;
   Barucci, Maria A.; Bertaux, Jean-Loup; Boudreault, Steve; Cremonese,
   Gabriele; Da Deppo, Vania; Davidsson, Björn; Debei, Stefano; De
   Cecco, Mariolino; Deller, Jakob; Fornasier, Sonia; Fulle, Marco;
   Gicquel, Adeline; Groussin, Olivier; Gutierrez, Pedro J.; Güttler,
   Carsten; Hofmann, Marc; Höfner, Sebastian; Hviid, Stubbe F.; Ip,
   Wing-Huen; Jorda, Laurent; Knollenberg, Jörg; Kramm, J. -Rainer;
   Kührt, Ekkehard; Küppers, Michael; La Forgia, Fiorangela; Lara,
   Luisa M.; Lee, Jui-Chi; Lin, Zhong-Yi; Lopez Moreno, Jose J.;
   Marzari, Francesco; Michalik, Harald; Mottola, Stefano; Preusker,
   Frank; Scholten, Frank; Thomas, Nicholas; Toth, Imre; Tubiana, Cecilia
2016A&A...592L...2P    Altcode:
  <BR /> Aims: We calculate the size-frequency distribution of the
  boulders on the southern hemisphere of comet 67P Churyumov-Gerasimenko
  (67P), which was in shadow before the end of April 2015. We compare
  the new results with those derived from the northern hemisphere
  and equatorial regions of 67P, highlighting the possible physical
  processes that lead to these boulder size distributions. <BR />
  Methods: We used images acquired by the OSIRIS Narrow Angle Camera
  (NAC) on 2 May 2015 at a distance of 125 km from the nucleus. The
  scale of this dataset is 2.3 m/px; the high resolution of the images,
  coupled with the favorable observation phase angle of 62°, provided the
  possibility to unambiguously identify boulders ≥7 m on the surface
  of 67P and to manually extract them with the software ArcGIS. We
  derived the size-frequency distribution of the illuminated southern
  hemisphere. <BR /> Results: We found a power-law index of -3.6 ± 0.2
  for the boulders on the southern hemisphere with a diameter range of
  7-35 m. The power-law index is equal to the one previously found on
  northern and equatorial regions of 67P, suggesting that similar boulder
  formation processes occur in both hemispheres. The power-law index is
  related to gravitational events triggered by sublimation and/or thermal
  fracturing causing regressive erosion. In addition, the presence of a
  larger number of boulders per km<SUP>2</SUP> in the southern hemisphere,
  which is a factor of 3 higher with respect to the northern hemisphere,
  suggests that the southernmost terrains of 67P are affected by a
  stronger thermal fracturing and sublimating activity, hence possibly
  causing larger regressive erosion and gravitational events.

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Title: Aswan site on comet 67P/Churyumov-Gerasimenko: Morphology,
    boulder evolution, and spectrophotometry
Authors: Pajola, Maurizio; Oklay, Nilda; La Forgia, Fiorangela;
   Giacomini, Lorenza; Massironi, Matteo; Bertini, Ivano; El-Maarry,
   M. R.; Marzari, Francesco; Preusker, Frank; Scholten, Frank; Höfner,
   Sebastian; Lee, Jui-Chi; Vincent, Jean-Baptiste; Groussin, Olivier;
   Naletto, Giampiero; Lazzarin, Monica; Barbieri, Cesare; Sierks,
   Holger; Lamy, Philippe; Rodrigo, Rafael; Koschny, Detlef; Rickman,
   Hans; Keller, Horst U.; Agarwal, Jessica; A'Hearn, Michael F.;
   Barucci, Maria A.; Bertaux, Jean-Loup; Cremonese, Gabriele; Da
   Deppo, Vania; Davidsson, Björn; De Cecco, Mariolino; Debei, Stefano;
   Ferri, Francesca; Fornasier, Sonia; Fulle, Marco; Güttler, Carsten;
   Gutierrez, Pedro J.; Hviid, Stubbe F.; Ip, Wing-Huen; Jorda, Laurent;
   Knollenberg, Jörg; Kramm, J. -Rainer; Küppers, Michael; Kürt,
   Ekkehard; Lara, Luisa M.; Lin, Zhong-Yi; Lopez Moreno, Jose J.;
   Magrin, Sara; Michalik, Harald; Mottola, Stefano; Thomas, Nicholas;
   Tubiana, Cecilia
2016A&A...592A..69P    Altcode:
  <BR /> Aims: We provide a detailed morphological analysis of the
  Aswan site on comet 67P/Churyumov-Gerasimenko (67P). We derive the
  size-frequency distribution of boulders ≥2 m and correlate this
  distribution with the gravitational slopes for the first time on a
  comet. We perform the spectral analysis of this region to understand if
  possible surface variegation is related to thedifferent surface textures
  observable on the different units. <BR /> Methods: We used two OSIRIS
  Narrow Angle Camera (NAC) image data sets acquired on September 19
  and 22, 2014, with a scale of 0.5 m/px. Gravitational slopes derived
  from the 3D shape model of 67P were used to identify and interpret
  the different units of the site. By means of the high-resolution
  NAC data sets, boulders ≥2.0 m can be unambiguously identified and
  extracted using the software ArcGIS. Coregistered and photometrically
  corrected color cubes were used to perform the spectral analyses,
  and we retrieved the spectral properties of the Aswan units. <BR />
  Results: The high-resolution morphological map of the Aswan site
  (0.68 km<SUP>2</SUP>) shows that this site is characterized by
  four different units: fine-particle deposits located on layered
  terrains, gravitational accumulation deposits, taluses, and the
  outcropping layered terrain. Multiple lineaments are identified on
  the Aswan cliff, such as fractures, exposed layered outcrops, niches,
  and terraces. Close to the terrace margin, several arched features
  observed in plan view suggest that the margin progressively retreats
  as a result of erosion. The size-frequency of boulders ≥2 m in
  the entire study area has a power-law index of -3.9 +0.2/-0.3 (1499
  boulders ≥2 m/km<SUP>2</SUP>), suggesting that the Aswan site is
  mainly dominated by gravitational events triggered by sublimation and/or
  thermal insolation weathering causing regressive erosion. The boulder
  size-frequency distribution versus gravitational slopes indicates that
  when higher gravitational slope terrains are considered, only boulders
  ≤10 m are identified, as well as steeper power-slope indices. In
  addition, no boulders ≥2 m are observed on slopes ≥50°. This may
  indicate that larger blocks detached from a sublimating cliff cannot
  rest at these slopes and consequently fall down. The spectral analysis
  performed on the site shows that despite different morphologic units, no
  spectral differences appear in the multiple textures. This may confirm
  a redistribution of particles across the nucleus as a consequence of
  airfall, whether coming from Hapi or from the southern hemisphere when
  it is active during perihelion.

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Title: Prominence material embedded in coronal mass ejections as
    observed with the LASCO-C2 coronagraph using polarization diagnostic
Authors: Lamy, Philippe; Boclet, Brice; Koutchmy, Serge
2016cosp...41E1107L    Altcode:
  Prominences are believed to be caused by the formation of a flux
  rope low in the magnetic structure that eventually erupts to form
  the CME. Indeed, many CME onset models (e.g., flux cancellation,
  mass loading) require the presence or formation of a prominence
  in order for the CME to erupt. The remnants of the cool prominence
  material is often seen as recognizable twisted structures inside the
  CME in the lines of He II at 304 Å, of D3 HeI at 587.5 nm, and of
  Hα at 656 nm, sometime up to a distance of several solar radii from
  the surface in the latter lines. The orange filter of the LASCO-C2
  coronagraph includes the D3 HeI line and its presence in the core of
  CMEs can be unambiguously detected on polarized images as polarization
  allows disentangling the contributions from the hot coronal plasma
  (the polarized Thomson scattered light by electrons) and from the
  unpolarised emission of cool prominence material. This has been made
  possible by an in-depth calibration that removes adverse instrumental
  effects. We will show several examples of CME with embedded prominence
  material and we will attempt to estimate the mass of this material to
  be compared with that of the CME. We will also exploit the polarization
  measurements to reconstruct the 3D geometry of the observed CMEs.

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Title: Coronal mass ejections over solar cycle 23 and 24 from LASCO-C2
    white-light images
Authors: Lamy, Philippe; Barlyaeva, Tatiana; Boclet, Brice
2016cosp...41E1108L    Altcode:
  It is now well established that coronal mass ejections (CMEs)
  play a major role in the heliosphere, starting from the corona
  to interplanetary space and interacting with planets. The almost
  uninterrupted observations by the LASCO coronagraph onboard SOHO since
  January 1996 have allowed an unprecedented view of CMEs over almost two
  solar cycles 23 and 24. The ARTEMIS-II catalog based on their automatic
  detection on high-quality calibrated synoptic maps of the corona offers
  a dataset free of selection effects. It is thus possible to perform
  an unbiased statistical analysis of their properties and investigate
  how they evolve with solar activity. We will present an extended
  comparison of their properties during the two solar cycles 23 and 24
  emphasizing the differences. We will further compare them with those
  of the standard indices of solar activity such as the international
  sunspot number (SSN), the sunspot area (SSA) and the radio flux at 10.7
  cm (F10.7) as well as those of their potential progenitors, flares
  and eruptive prominences, in order to ascertain their connection,
  and we will consider the two hemispheres separately whenever possible.

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Title: Detection of changes of the surface morphology of the nucleus
    of comet 67P/Churyumov-Gerasimenko - Implications for the erosion
Authors: Lamy, Philippe; Groussin, Olivier; El-Maarry, M. R.; Faury,
   Guillaume; Auger, Anne-Thérèse
2016cosp...41E1109L    Altcode:
  Search for morphological changes at the surface of the nucleus of comet
  67P/Churyumov-Gerasimenko (67/P C-G) since its perihelion passage in
  August 2015 has been a major objective of the OSIRIS team in order
  to understand the erosion processes. At time of writing, the changes
  detected so far at a distance of 48 km (that is a pixel scale of 90
  cm for the OSIRIS Narrow Angle Camera) are subtle even in regions
  which were the most exposed to solar illumination around perihelion
  time: Imhotep, Khonsu and Khepry. In this presentation, we will
  concentrate on the Khepry region where several changes of different
  kinds have been positively detected: disappearance of several bright
  spots, localized receding of a large part (roughly 40 x 130 m) of the
  surface by approximately 12 m (that could result from either erosion
  or localized collapse), and appearance of several new boulders. As
  the Rosetta-comet distance will keep decreasing, we hope to report
  further changes at the COSPAR conference. We will finally confront
  quantitative estimates of the putative eroded mass with independent
  evidences coming from in-situ as well as remote-sensing observations
  carried over several past apparitions.

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Title: Physical properties and dynamical relation of the circular
    depressions on comet 67P/Churyumov-Gerasimenko
Authors: Ip, W. -H.; Lai, I. -L.; Lee, J. -C.; Cheng, Y. -C.; Li,
   Y.; Lin, Z. -Y.; Vincent, J. -B.; Besse, S.; Sierks, H.; Barbieri,
   C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller,
   H. U.; Agarwal, J.; A'Hearn, M. F.; Barucci, M. A.; Bertaux,
   J. -L.; Bertini, I.; Bodewits, D.; Boudreault, S.; Cremonese, G.;
   Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.; El-Maarry,
   M. R.; Fornasier, S.; Fulle, M.; Groussin, O.; Gutiérrez, P. J.;
   Güttler, C.; Hviid, S. F.; Jorda, L.; Knollenberg, J.; Kovacs, G.;
   Kramm, J. -R.; Kührt, E.; Küppers, M.; La Forgia, F.; Lara, L. M.;
   Lazzarin, M.; López-Moreno, J. J.; Lowry, S.; Marchi, S.; Marzari,
   F.; Michalik, H.; Mottola, S.; Naletto, G.; Oklay, N.; Pajola, M.;
   Thomas, N.; Toth, E.; Tubiana, C.
2016A&A...591A.132I    Altcode:
  <BR /> Aims: We aim to characterize the circular depressions of
  comet 67P/Churyumov-Gerasimenko and investigate whether such surface
  morphology of a comet nucleus is related to the cumulative sublimation
  effect since becoming a Jupiter family comet (JFC). <BR /> Methods:
  The images from the Rosetta/OSIRIS science camera experiment are used
  to construct size frequency distributions of the circular depression
  structures on comet 67P and they are compared with those of the JFCs
  81P/Wild 2, 9P/Tempel 1, and 103P/Hartley 2. The orbital evolutionary
  histories of these comets over the past 100 000 yr are analyzed
  statistically and compared with each other. <BR /> Results: The global
  distribution of the circular depressions over the surface of 67P is
  charted and classified. Descriptions are given to the characteristics
  and cumulative size frequency distribution of the identified
  features. Orbital statistics of the JFCs visited by spacecraft are
  derived. <BR /> Conclusions: The size frequency distribution of the
  circular depressions is found to have a similar power law distribution
  to those of 9P/Tempel 1 and 81P/Wild 2. This might imply that they
  could have been generated by the same process. Orbital integration
  calculation shows that the surface erosion histories of 81P/Wild 2,
  and 9P/Tempel 1 could be shorter than those of 67P, 103 P/Hartley 2 and
  19P/Borrelly. From this point of view, the circular depressions could
  be dated back to the pre-JFC phase or the transneptunian phase of these
  comets. The north-south asymmetry in the distribution of the circular
  depressions could be associated with the heterogeneous structure of
  the nucleus of comet 67P and/or the solar insolation history.

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Title: Possible interpretation of the precession of comet
    67P/Churyumov-Gerasimenko
Authors: Gutiérrez, P. J.; Jorda, L.; Gaskell, R. W.; Davidsson,
   B. J. R.; Capanna, C.; Hviid, S. F.; Keller, H. U.; Maquet, L.;
   Mottola, S.; Preusker, F.; Scholten, F.; Lara, L. M.; Moreno,
   F.; Rodrigo, R.; Sierks, H.; Barbieri, C.; Lamy, P.; Koschny, D.;
   Rickman, H.; Agarwal, J.; A'Hearn, M. F.; Auger, A. T.; Barucci, M. A.;
   Bertaux, J. L.; Bertini, I.; Cremonese, G.; Da Deppo, V.; Debei, S.;
   De Cecco, M.; El-Maarry, M. R.; Fornasier, S.; Fulle, M.; Groussin,
   O.; Gutiérrez-Marques, P.; Güttler, C.; Ip, W. H.; Knollenberg, J.;
   Kramm, J. R.; Kührt, E.; Küppers, M.; La Forgia, F.; Lazzarin, M.;
   López-Moreno, J. J.; Magrin, S.; Marchi, S.; Marzari, F.; Naletto,
   G.; Oklay, N.; Pajola, M.; Pommerol, A.; Sabau, D.; Thomas, N.; Toth,
   I.; Tubiana, C.; Vincent, J. B.
2016A&A...590A..46G    Altcode:
  Context. Data derived from the reconstruction of the nucleus shape
  of comet 67P/Churyumov-Gerasimenko (67P) from images of the OSIRIS
  camera onboard ROSETTA show evidence that the nucleus rotates in
  complex mode. First, the orientation of the spin axis is not fixed in
  an inertial reference frame, which suggests a precessing motion around
  the angular momentum vector with a periodicity of approximately 257
  h ± 12 h.Second, periodograms of the right ascension and declination
  (RA/Dec) coordinates of the body-frame Z axis show a very significant
  (higher than 99.99%) periodicity at 276 h ± 12 h, different from the
  rotational period of 12.40 h as previously determined from light-curve
  analysis. <BR /> Aims: The main goal is to interpret the data and
  associated periodicities of the spin axis orientation in space. <BR
  /> Methods: We analyzed the spin axis orientation in space and
  associated periodicities and compared them with solutions of Euler
  equations under the assumption that the body rotates in torque-free
  conditions. Statistical tests comparing the observationally derived
  spin axis orientation with the outcome from simulations were applied
  to determine the most likely inertia moments, excitation level,
  and periods. <BR /> Results: Under the assumption that the body is
  solid-rigid and rotates in torque-free conditions, the most likely
  interpretation is that 67P is spinning around the principal axis with
  the highest inertia moment with a period of about 13 h. At the same
  time, the comet precesses around the angular momentum vector with
  a period of about 6.35 h. While the rotating period of such a body
  would be about 12.4 h, RA/Dec coordinates of the spin axis would have
  a periodicity of about 270 h as a result of the combination of the
  two aforementioned motions. <BR /> Conclusions: The most direct and
  simple interpretation of the complex rotation of 67P requires a ratio
  of inertia moments significantly higher than that of a homogeneous body.

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Title: Subsurface Characterization of 67P/Churyumov-Gerasimenko’s
    Abydos Site
Authors: Brugger, B.; Mousis, O.; Morse, A.; Marboeuf, U.; Jorda, L.;
   Guilbert-Lepoutre, A.; Andrews, D.; Barber, S.; Lamy, P.; Luspay-Kuti,
   A.; Mandt, K.; Morgan, G.; Sheridan, S.; Vernazza, P.; Wright, I. P.
2016ApJ...822...98B    Altcode: 2016arXiv160305893B
  On 2014 November 12, the ESA/Rosetta descent module Philae landed on
  the Abydos site of comet 67P/Churyumov-Gerasimenko. Aboard this module,
  the Ptolemy mass spectrometer measured a CO/CO<SUB>2</SUB> ratio of
  0.07 ± 0.04, which differs substantially from the value obtained in
  the coma by the Rosetta/ROSINA instrument, suggesting a heterogeneity
  in the comet nucleus. To understand this difference, we investigated
  the physicochemical properties of the Abydos subsurface, leading to
  CO/CO<SUB>2</SUB> ratios close to that observed by Ptolemy at the
  surface of this region. We used a comet nucleus model that takes into
  account different water ice phase changes (amorphous ice, crystalline
  ice, and clathrates) as well as diffusion of molecules throughout the
  pores of the matrix. The input parameters of the model were optimized
  for the Abydos site, and the ROSINA CO/CO<SUB>2</SUB> measured ratio is
  assumed to correspond to the bulk value in the nucleus. We find that all
  considered structures of water ice are able to reproduce the Ptolemy
  observation with a time difference not exceeding ∼50 days, I.e.,
  lower than ∼2% on 67P/Churyumov-Gerasimenko’s orbital period. The
  suspected heterogeneity of 67P/Churyumov-Gerasimenko’s nucleus is also
  found possible only if it is constituted of crystalline ices. If the icy
  phase is made of amorphous ice or clathrates, the difference between
  Ptolemy and ROSINA’s measurements would rather originate from the
  spatial variations in illumination on the nucleus surface. An eventual
  new measurement of the CO/CO<SUB>2</SUB> ratio at Abydos by Ptolemy
  could be decisive to distinguish between the three water ice structures.

---------------------------------------------------------
Title: Extreme 3D reconstruction of the final ROSETTA/PHILAE
    landing site
Authors: Capanna, Claire; Jorda, Laurent; Lamy, Philippe; Gesquiere,
   Gilles; Delmas, Cédric; Durand, Joelle; Garmier, Romain; Gaudon,
   Philippe; Jurado, Eric
2016EGUGA..18.4522C    Altcode:
  The Philae lander aboard the Rosetta spacecraft successfully landed
  at the surface of comet 67P/Churyumov-Gerasimenko (hereafter 67P/C-G)
  after two rebounds on November 12, 2014. The final landing site, now
  known as « Abydos », has been identified on images acquired by the
  OSIRIS imaging system onboard the Rosetta orbiter[1]. The available
  images of Abydos are very limited in number and reveal a very extreme
  topography containing cliffs and overhangs. Furthermore, the surface
  is only observed under very high incidence angles of 60° on average,
  which implies that the images also exhibit lots of cast shadows. This
  makes it very difficult to reconstruct the 3D topography with standard
  methods such as photogrammetry or standard clinometry. We apply a
  new method called ”Multiresolution PhotoClinometry by Deformation”
  (MPCD, [2]) to retrieve the 3D topography of the area around Abydos. The
  method works in two main steps: (i) a DTM of this region is extracted
  from a low resolution MPCD global shape model of comet 67P/C-G,
  and (ii) the resulting triangular mesh is progressively deformed at
  increasing spatial sampling down to 0.25 m in order to match a set
  of 14 images of Abydos with projected pixel scales between 1 and 8
  m. The method used to perform the image matching is a quasi-Newton
  non-linear optimization method called L-BFGS-b[3] especially suited to
  large-scale problems. Finally, we also checked the compatibility of the
  final MPCD digital terrain model with a set of five panoramic images
  obtained by the CIVA-P instrument aboard Philae[4]. [1] Lamy et al.,
  2016, submitted. [2] Capanna et al., Three dimensional reconstruction
  using multiresoluton photoclinometry by deformation, The visual
  Computer, v. 29(6-8) pp. 825-835, 2013. [3] Morales et al., Remark on
  "Algorithm 778: L-BFGS-B: Fortran subroutines for large-scale bound
  constrained optimization", v.38(1) pp.1-4, ACM Trans. Math. Softw.,
  2011 [4] Bibring et al., 67P/Churyumov-Gerasimenko surface properties
  as derived from CIVA panoramic images, Science, v. 349(6247), 2015

---------------------------------------------------------
Title: 20 months at 67P/Churyumov-Gerasimenko: The view from
    Rosetta/OSIRIS
Authors: Sierks, Holger; Güttler, Carsten; Barbieri, Cesare; Lamy,
   Philippe; Rodrigo, Rafael; Koschny, Detlef; Rickman, Hans
2016EGUGA..1815782S    Altcode:
  After arrival in August 2014, the Rosetta spacecraft is now at
  comet 67P/Churyumov-Gerasimenko for one and a half years. A rather
  inactive body at that time was approaching the Sun, passing through
  its perihelion and peak of activity in August/September 2015 and is
  now moving out, away from the Sun. During the whole time, the comet
  was observed by the scientific imaging system OSIRIS onboard Rosetta,
  mapping the nucleus' surface and monitoring the comet's dust and gas
  coma. This presentation shall summarize the results obtained so far by
  the OSIRIS team and give a general picture on our current understanding
  of comets in general and 67P in particular.

---------------------------------------------------------
Title: The State of the Corona During the Weak Solar Cycle 24:
    the View from LASCO Images
Authors: Barlyaeva, T.; Lamy, P.; Llebaria, A.; Boclet, B.
2016ASPC..504..287B    Altcode:
  The LASCO-C2 coronagraph onboard SOHO continues its white-light imaging
  of the corona from 1.5 to 6.0 solar radii, thus allowing investigating
  the consequences of the weak Solar Cycle 24 on the corona and comparing
  it to the previous cycle (23). Temporal variations of the global
  radiance of the corona are presented. We pay particular attention to
  the mid-term variations which are distinctly different between the
  two cycles and highlight the similarities and differences. Finally,
  we rely on our ARTEMIS II catalog of coronal mass ejections (CMEs)
  to compare their global rates during these two cycles.

---------------------------------------------------------
Title: Observations and analysis of a curved jet in the coma of
    comet 67P/Churyumov-Gerasimenko
Authors: Lin, Z. -Y.; Lai, I. -L.; Su, C. -C.; Ip, W. -H.; Lee, J. -C.;
   Wu, J. -S.; Vincent, J. -B.; La Forgia, F.; Sierks, H.; Barbieri,
   C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller,
   H. U.; Agarwal, J.; A'Hearn, M. F.; Barucci, M. A.; Bertaux, J. -L.;
   Bertini, I.; Bodewits, D.; Cremonese, G.; Da Deppo, V.; Davidsson,
   B.; Debei, S.; De Cecco, M.; Fornasier, S.; Fulle, M.; Groussin, O.;
   Gutiérrez, P. J.; Güttler, C.; Hviid, S. F.; Jorda, L.; Knollenberg,
   J.; Kovacs, G.; Kramm, J. -R.; Kührt, E.; Küppers, M.; Lara, L. M.;
   Lazzarin, M.; López-Moreno, J. J.; Lowry, S.; Marzari, F.; Michalik,
   H.; Mottola, S.; Naletto, G.; Oklay, N.; Pajola, M.; Rożek, A.;
   Thomas, N.; Tubiana, C.
2016A&A...588L...3L    Altcode: 2016arXiv160502095L
  <BR /> Aims: We analyze the physical properties and dynamical
  origin of a curved jet of comet 67P/Churyumov-Gerasimenko that was
  observed repeatedly in several nucleus rotations starting on May 30
  and persisting until early August, 2015. <BR /> Methods: We simulated
  the motion of dust grains ejected from the nucleus surface under the
  influence of the gravity and viscous drag effect of the expanding gas
  flow from the rotating nucleus. <BR /> Results: The formation of the
  curved jet is a combination of the size of the dust particles (~0.1-1
  mm) and the location of the source region near the nucleus equator. This
  enhances the spiral feature of the collimated dust stream after the dust
  is accelerated to a terminal speed on the order of m s<SUP>-1</SUP>.

---------------------------------------------------------
Title: Evolution of the Dust Size Distribution of Comet
    67P/Churyumov-Gerasimenko from 2.2 au to Perihelion
Authors: Fulle, M.; Marzari, F.; Della Corte, V.; Fornasier, S.;
   Sierks, H.; Rotundi, A.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.;
   Koschny, D.; Rickman, H.; Keller, H. U.; López-Moreno, J. J.;
   Accolla, M.; Agarwal, J.; A'Hearn, M. F.; Altobelli, N.; Barucci,
   M. A.; Bertaux, J. -L.; Bertini, I.; Bodewits, D.; Bussoletti, E.;
   Colangeli, L.; Cosi, M.; Cremonese, G.; Crifo, J. -F.; Da Deppo,
   V.; Davidsson, B.; Debei, S.; De Cecco, M.; Esposito, F.; Ferrari,
   M.; Giovane, F.; Gustafson, B.; Green, S. F.; Groussin, O.; Grün,
   E.; Gutierrez, P.; Güttler, C.; Herranz, M. L.; Hviid, S. F.; Ip,
   W.; Ivanovski, S. L.; Jerónimo, J. M.; Jorda, L.; Knollenberg, J.;
   Kramm, R.; Kührt, E.; Küppers, M.; Lara, L.; Lazzarin, M.; Leese,
   M. R.; López-Jiménez, A. C.; Lucarelli, F.; Mazzotta Epifani, E.;
   McDonnell, J. A. M.; Mennella, V.; Molina, A.; Morales, R.; Moreno,
   F.; Mottola, S.; Naletto, G.; Oklay, N.; Ortiz, J. L.; Palomba, E.;
   Palumbo, P.; Perrin, J. -M.; Rietmeijer, F. J. M.; Rodríguez, J.;
   Sordini, R.; Thomas, N.; Tubiana, C.; Vincent, J. -B.; Weissman, P.;
   Wenzel, K. -P.; Zakharov, V.; Zarnecki, J. C.
2016ApJ...821...19F    Altcode:
  The Rosetta probe, orbiting Jupiter-family comet
  67P/Churyumov-Gerasimenko, has been detecting individual dust particles
  of mass larger than 10<SUP>-10</SUP> kg by means of the GIADA dust
  collector and the OSIRIS Wide Angle Camera and Narrow Angle Camera
  since 2014 August and will continue until 2016 September. Detections
  of single dust particles allow us to estimate the anisotropic dust flux
  from 67P, infer the dust loss rate and size distribution at the surface
  of the sunlit nucleus, and see whether the dust size distribution of
  67P evolves in time. The velocity of the Rosetta orbiter, relative
  to 67P, is much lower than the dust velocity measured by GIADA, thus
  dust counts when GIADA is nadir-pointing will directly provide the
  dust flux. In OSIRIS observations, the dust flux is derived from the
  measurement of the dust space density close to the spacecraft. Under
  the assumption of radial expansion of the dust, observations in the
  nadir direction provide the distance of the particles by measuring
  their trail length, with a parallax baseline determined by the motion
  of the spacecraft. The dust size distribution at sizes &gt;1 mm
  observed by OSIRIS is consistent with a differential power index of
  -4, which was derived from models of 67P’s trail. At sizes &lt;1 mm,
  the size distribution observed by GIADA shows a strong time evolution,
  with a differential power index drifting from -2 beyond 2 au to -3.7
  at perihelion, in agreement with the evolution derived from coma and
  tail models based on ground-based data. The refractory-to-water mass
  ratio of the nucleus is close to six during the entire inbound orbit
  and at perihelion.

---------------------------------------------------------
Title: Mapping of the source regions of the dust jets on comet 67P
Authors: Ip, Wing-Huen; Lai, Ian-Lin; Lee, Jui-Chi; Lin, Zhong-Yi;
   Chen, Yu; Chien, Ting-Wei; Chen, Yu-Min; Vincent, Jean-Baptiste;
   Sierks, Holger; Barbieri, Cesare; Lamy, Philippe. L.; Rodrigo, Rafael;
   Koschny, Detlef; Rickman, Hans; Keller, Uwe; Osiris Team
2016EGUGA..18.5347I    Altcode:
  Because of the inclination of the rotational axis to the orbital
  plane and the orbital motion around the Sun, the sunlit regions on
  the nucleus surface of comet 67P/Churyumov-Gerasimenko moved from the
  northern hemisphere to the sourthern hemisphere between August, 2014
  and October, 2015. From the comparison of the dust jet features in
  images taken at successive time series, the footpoints of these jets
  can be identified by a projection method. The distributiosn of the
  corresponding source regions can be compared with the geomorphology
  of the nucleus surface from inbound to outbound. The correlation
  of the dust jet activity with the volatile outgassing phenomenon as
  monitored by different scientific instruments onboard Rosetta will
  provide important information on the sublimation process.

---------------------------------------------------------
Title: Photometry of dust grains of comet 67P and connection with
    nucleus regions
Authors: Cremonese, G.; Simioni, E.; Ragazzoni, R.; Bertini, I.;
   La Forgia, F.; Pajola, M.; Oklay, N.; Fornasier, S.; Lazzarin, M.;
   Lucchetti, A.; Sierks, H.; Barbieri, C.; Lamy, P.; Rodrigo, R.;
   Koschny, D.; Rickman, H.; Keller, H. U.; A'Hearn, M. F.; Agarwal,
   J.; Barucci, M. A.; Bertaux, J. -L.; Da Deppo, V.; Davidsson, B.;
   De Cecco, M.; Debei, S.; Fulle, M.; Groussin, O.; Güttler, C.;
   Gutierrez, P. J.; Hviid, S. F.; Ip, W. -H.; Jorda, L.; Knollenberg,
   J.; Kramm, J. -R.; Kueppers, M.; Kürt, E.; Lara, L. M.; Magrin, S.;
   Lopez Moreno, J. J.; Marzari, F.; Mottola, S.; Naletto, G.; Preusker,
   F.; Scholten, F.; Thomas, N.; Tubiana, C.; Vincent, J. -B.
2016A&A...588A..59C    Altcode:
  <BR /> Aims: Multiple pairs of high-resolution images of the dust coma
  of comet 67P/Churyumov-Gerasimenko have been collected by OSIRIS onboard
  Rosetta allowing extraction and analysis of dust grain tracks. <BR
  /> Methods: We developed a quasi automatic method to recognize and
  to extract dust tracks in the Osiris images providing size, FWHM and
  photometric data. The dust tracks characterized by a low signal-to-noise
  ratio were checked manually. We performed the photometric analysis
  of 70 dust grain tracks observed on two different Narrow Angle Camera
  images in the two filters F24 and F28, centered at λ = 480.7 nm and
  at λ = 743.7 nm, respectively, deriving the color and the reddening
  of each one. We then extracted several images of the nucleus observed
  with the same filters and with the same phase angle to be compared
  with the dust grain reddening. <BR /> Results: Most of the dust grain
  reddening is very similar to the nucleus values, confirming they come
  from the surface or subsurface layer. The histogram of the dust grain
  reddening has a secondary peak at negative values and shows some grains
  with values higher than the nucleus, suggesting a different composition
  from the surface grains. One hypothesis comes from the negative values
  point at the presence of hydrated minerals in the comet.

---------------------------------------------------------
Title: The dust environment of comet 67P/Churyumov-Gerasimenko from
    Rosetta OSIRIS and VLT observations in the 4.5 to 2.9 AU heliocentric
    distance range inbound
Authors: Moreno, F.; Snodgrass, C.; Hainaut, O.; Tubiana, C.; Sierks,
   H.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.;
   Keller, H. U.; Agarwal, J.; A'Hearn, M. F.; Barucci, M. A.; Bertaux,
   J. -L.; Bertini, I.; Besse, S.; Bodewits, D.; Cremonese, G.; Da Deppo,
   V.; Davidsson, B.; Debei, S.; De Cecco, M.; Ferri, F.; Fornasier,
   S.; Fulle, M.; Groussin, O.; Gutiérrez, P. J.; Gutiérrez-Marques,
   P.; Güttler, C.; Hviid, S. F.; Ip, W. -H.; Jorda, L.; Knollenberg,
   J.; Kovacs, G.; Kramm, J. -R.; Kührt, E.; Küppers, M.; Lara, L. M.;
   Lazzarin, M.; López-Moreno, J. J.; Marzari, F.; Mottola, S.; Naletto,
   G.; Oklay, N.; Pajola, M.; Thomas, N.; Vincent, J. B.; Della Corte,
   V.; Fitzsimmons, A.; Faggi, S.; Jehin, E.; Opitom, C.; Tozzi, G. -P.
2016A&A...587A.155M    Altcode: 2016arXiv160201965M
  Context. The ESA Rosetta spacecraft, currently orbiting around comet
  67P/Churyumov-Gerasimenko, has already provided in situ measurements
  of the dust grain properties from several instruments,particularly
  OSIRIS and GIADA. We propose adding value to those measurements by
  combining them with ground-based observations of the dust tail to
  monitor the overall, time-dependent dust-production rate and size
  distribution. <BR /> Aims: To constrain the dust grain properties,
  we take Rosetta OSIRIS and GIADA results into account, and combine
  OSIRIS data during the approach phase (from late April to early June
  2014) with a large data set of ground-based images that were acquired
  with the ESO Very Large Telescope (VLT) from February to November
  2014. <BR /> Methods: A Monte Carlo dust tail code, which has already
  been used to characterise the dust environments of several comets and
  active asteroids, has been applied to retrieve the dust parameters. Key
  properties of the grains (density, velocity, and size distribution) were
  obtained from Rosetta observations: these parameters were used as input
  of the code to considerably reduce the number of free parameters. In
  this way, the overall dust mass-loss rate and its dependence on the
  heliocentric distance could be obtained accurately. <BR /> Results:
  The dust parameters derived from the inner coma measurements by OSIRIS
  and GIADA and from distant imaging using VLT data are consistent,
  except for the power index of the size-distribution function, which
  is α = -3, instead of α = -2, for grains smaller than 1 mm. This is
  possibly linked to the presence of fluffy aggregates in the coma. The
  onset of cometary activity occurs at approximately 4.3 AU, with a dust
  production rate of 0.5 kg/s, increasing up to 15 kg/s at 2.9 AU. This
  implies a dust-to-gas mass ratio varying between 3.8 and 6.5 for the
  best-fit model when combined with water-production rates from the
  MIRO experiment.

---------------------------------------------------------
Title: Are fractured cliffs the source of cometary dust jets? Insights
    from OSIRIS/Rosetta at 67P/Churyumov-Gerasimenko
Authors: Vincent, J. -B.; Oklay, N.; Pajola, M.; Höfner, S.;
   Sierks, H.; Hu, X.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny,
   D.; Rickman, H.; Keller, H. U.; A'Hearn, M. F.; Barucci, M. A.;
   Bertaux, J. -L.; Bertini, I.; Besse, S.; Bodewits, D.; Cremonese,
   G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.; El-Maarry,
   M. R.; Fornasier, S.; Fulle, M.; Groussin, O.; Gutiérrez, P. J.;
   Gutiérrez-Marquez, P.; Güttler, C.; Hofmann, M.; Hviid, S. F.;
   Ip, W. -H.; Jorda, L.; Knollenberg, J.; Kovacs, G.; Kramm, J. -R.;
   Kührt, E.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Lin, Z. -Y.;
   Lopez Moreno, J. J.; Lowry, S.; Marzari, F.; Massironi, M.; Moreno,
   F.; Mottola, S.; Naletto, G.; Preusker, F.; Scholten, F.; Shi, X.;
   Thomas, N.; Toth, I.; Tubiana, C.
2016A&A...587A..14V    Altcode: 2015arXiv151203193V
  Context. Dust jets (I.e., fuzzy collimated streams of cometary material
  arising from the nucleus) have been observed in situ on all comets
  since the Giotto mission flew by comet 1P/Halley in 1986, and yet
  their formation mechanism remains unknown. Several solutions have been
  proposed involving either specific properties of the active areas or the
  local topography to create and focus the gas and dust flows. While the
  nucleus morphology seems to be responsible for the larger features, high
  resolution imagery has shown that broad streams are composed of many
  smaller jets (a few meters wide) that connect directly to the nucleus
  surface. <BR /> Aims: We monitored these jets at high resolution and
  over several months to understand what the physical processes are that
  drive their formation and how this affects the surface. <BR /> Methods:
  Using many images of the same areas with different viewing angles,
  we performed a 3-dimensional reconstruction of collimated jets and
  linked them precisely to their sources on the nucleus. <BR /> Results:
  We show here observational evidence that the northern hemisphere
  jets of comet 67P/Churyumov-Gerasimenko arise from areas with sharp
  topographic changes and describe the physical processes involved. We
  propose a model in which active cliffs are the main source of jet-like
  features and therefore of the regions eroding the fastest on comets. We
  suggest that this is a common mechanism taking place on all comets.

---------------------------------------------------------
Title: The Comparison of Total Electron Content Between Radio and
    Thompson Scattering
Authors: Jensen, E. A.; Frazin, R.; Heiles, C.; Lamy, P.; Llebaria,
   A.; Anderson, J. D.; Bisi, M. M.; Fallows, R. A.
2016SoPh..291..465J    Altcode: 2016SoPh..tmp....2J
  The total electron content (TEC) of the solar corona in June 2002
  is calculated by three observational techniques and the results are
  compared. The first technique is solar rotational tomography (SRT)
  applied to a 14-day time series of LASCO-C2 polarized brightness images,
  and the other two techniques use the Cassini spacecraft radio beacon
  for Doppler tracking (phase delay) and ranging (group delay). While
  the Doppler-tracking technique has an arbitrary zero-point, it is
  otherwise found that the three methods produce consistent estimates of
  the TEC to within established uncertainties, providing an independent
  check on the calibrations. The verification of the accuracy of the
  Doppler-tracking technique enables a significant improvement to the
  use of spacecraft data sets in studying the heliosphere: the density
  component to Faraday rotation can be separated from the magnetic-field
  component as variable structures cross, such as coronal mass ejections
  and magnetohydrodynamic waves. Furthermore, we show that the unique
  frequency-time variable characteristics of the hydrodynamic components
  of waves can be studied. Based on this work, future Faraday rotation
  studies of variable solar phenomena will isolate the electron density
  changes from the magnetic-field contribution. This capability will
  enable advanced research into variable heliospheric magnetic fields.

---------------------------------------------------------
Title: THERMAP: a mid-infrared spectro-imager for space missions to
    small bodies in the inner solar system
Authors: Groussin, O.; Licandro, J.; Helbert, J.; Reynaud, J. L.;
   Levacher, P.; Reyes García-Talavera, M.; Alí-Lagoa, V.; Blanc, P. E.;
   Brageot, E.; Davidsson, B.; Delbó, M.; Deleuze, M.; Delsanti, A.;
   Diaz Garcia, J. J.; Dohlen, K.; Ferrand, D.; Green, S. F.; Jorda, L.;
   Joven Álvarez, E.; Knollenberg, J.; Kührt, E.; Lamy, P.; Lellouch,
   E.; Le Merrer, J.; Marty, B.; Mas, G.; Rossin, C.; Rozitis, B.;
   Sunshine, J.; Vernazza, P.; Vives, S.
2016ExA....41...95G    Altcode: 2015arXiv150902725G; 2015ExA...tmp...56G
  We present THERMAP, a mid-infrared spectro-imager for space missions
  to small bodies in the inner solar system, developed in the framework
  of the MarcoPolo-R asteroid sample return mission. THERMAP is very well
  suited to characterize the surface thermal environment of a NEO and to
  map its surface composition. The instrument has two channels, one for
  imaging and one for spectroscopy: it is both a thermal camera with full
  2D imaging capabilities and a slit spectrometer. THERMAP takes advantage
  of the recent technological developments of uncooled microbolometer
  arrays, sensitive in the mid-infrared spectral range. THERMAP can
  acquire thermal images (8-18 μm) of the surface and perform absolute
  temperature measurements with a precision better than 3.5 K above 200
  K. THERMAP can acquire mid-infrared spectra (8-16 μm) of the surface
  with a spectral resolution Δλ of 0.3 μm. For surface temperatures
  above 350 K, spectra have a signal-to-noise ratio &gt;60 in the spectral
  range 9-13 μm where most emission features occur.

---------------------------------------------------------
Title: Variegation of comet 67P/Churyumov-Gerasimenko in regions
    showing activity
Authors: Oklay, N.; Vincent, J. -B.; Fornasier, S.; Pajola, M.;
   Besse, S.; Davidsson, B. J. R.; Lara, L. M.; Mottola, S.; Naletto, G.;
   Sierks, H.; Barucci, A. M.; Scholten, F.; Preusker, F.; Pommerol, A.;
   Masoumzadeh, N.; Lazzarin, M.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.;
   Koschny, D.; Rickman, H.; A'Hearn, M. F.; Bertaux, J. -L.; Bertini,
   I.; Bodewits, D.; Cremonese, G.; Da Deppo, V.; Debei, S.; De Cecco,
   M.; Fulle, M.; Groussin, O.; Gutiérrez, P. J.; Güttler, C.; Hall,
   I.; Hofmann, M.; Hviid, S. F.; Ip, W. -H.; Jorda, L.; Keller, H. U.;
   Knollenberg, J.; Kovacs, G.; Kramm, J. -R.; Kührt, E.; Küppers,
   M.; Lin, Z. -Y.; Lopez Moreno, J. J.; Marzari, F.; Moreno, F.; Shi,
   X.; Thomas, N.; Toth, I.; Tubiana, C.
2016A&A...586A..80O    Altcode:
  Aims.We carried out an investigation of the surface variegation of comet
  67P/Churyumov-Gerasimenko, the detection of regions showing activity,
  the determination of active and inactive surface regions of the comet
  with spectral methods, and the detection of fallback material. <BR
  /> Methods: We analyzed multispectral data generated with Optical,
  Spectroscopic, and Infrared Remote Imaging System (OSIRIS) narrow
  angle camera (NAC) observations via spectral techniques, reflectance
  ratios, and spectral slopes in order to study active regions. We
  applied clustering analysis to the results of the reflectance ratios,
  and introduced the new technique of activity thresholds to detect
  areas potentially enriched in volatiles. <BR /> Results: Local
  color inhomogeneities are detected over the investigated surface
  regions. Active regions, such as Hapi, the active pits of Seth and
  Ma'at, the clustered and isolated bright features in Imhotep, the
  alcoves in Seth and Ma'at, and the large alcove in Anuket, have bluer
  spectra than the overall surface. The spectra generated with OSIRIS
  NAC observations are dominated by cometary emissions of around 700
  nm to 750 nm as a result of the coma between the comet's surface and
  the camera. One of the two isolated bright features in the Imhotep
  region displays an absorption band of around 700 nm, which probably
  indicates the existence of hydrated silicates. An absorption band with
  a center between 800-900 nm is tentatively observed in some regions
  of the nucleus surface. This absorption band can be explained by the
  crystal field absorption of Fe<SUP>2+</SUP>, which is a common spectral
  feature seen in silicates.

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Title: First analysis of the size-frequency distribution of boulders
    ge  7m on comet 67P
Authors: Pajola, M.; Vincent, J. B.; Güttler, C.; Lee, J. -C.;
   Massironi, M.; Bertini, I.; Simioni, E.; Marzari, F.; Giacomini, L.;
   Barbieri, C.; Cremonese, G.; Naletto, G.; Pommerol, A.; El Maarry,
   M. R.; Besse, S.; Küppers, M.; La Forgia, F.; Lazzarin, M.; Thomas,
   N.; Auger, A. T.; Ip, W. -H.; Lin, Z. -Y.; Sierks, H.; OSIRIS Team;
   A'Hearn, M. F.; Barucci, M. A.; Bertaux, J. -L.; Da Deppo, V.;
   Davidsson, B.; De Cecco, M.; Debei, S.; Ferri, F.; Fornasier, S.;
   Fulle, M.; Groussin, O.; Gutierrez, P. J.; Hviid, S. F.; Jorda, L.;
   Keller, H. U.; Knollenberg, J.; Koschny, D.; Kramm, J. -R.; Kürt,
   E.; Lamy, P.; Lara, L. M.; Lopez Moreno, J. J.; Magrin, S.; Michalik,
   H.; Moissl, R.; Mottola, S.; Oklay, N.; Preusker, F.; Rickman, H.;
   Rodrigo, R.; Scholten, F.; Tubiana, C.
2016MmSAI..87..156P    Altcode:
  Images of the surface of comet 67P Churyumov-Gerasimenko taken by
  the OSIRIS camera on board the Rosetta spacecraft have been used to
  study the statistical distribution and morphological properties of
  both cluster and isolated roundish structures ('boulders') scattered
  all over the surface. We used NAC images taken on Aug 5-6, 2014, at a
  distance between 131.45 - 109.76 km, with a spatial resolution ranging
  from 2.44 - 2.03 m/px (Fig. 1). Such data cover a full rotation of 67P,
  providing the first ever full size frequency distribution coverage of
  boulders ≥ 7m visible on a cometary illuminated side. Boulders are
  ubiquitous on the head, neck, and body of 67P \citep{thomas15}. The
  initial count of 4,976 boulders was reduced to 3,546 for statistical
  purposes taking into consideration only those with a diameter larger
  than 7 m \citep{pajola15}.

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Title: Characterization of the Abydos region through OSIRIS
    high-resolution images in support of CIVA measurements
Authors: Lucchetti, A.; Cremonese, G.; Jorda, L.; Poulet, F.; Bibring,
   J. -P.; Pajola, M.; La Forgia, F.; Massironi, M.; El-Maarry, M. R.;
   Oklay, N.; Sierks, H.; Barbieri, C.; Lamy, P.; Rodrigo, R.; Koschny,
   D.; Rickman, H.; Keller, H. U.; Agarwal, J.; A'Hearn, M. F.; Barucci,
   M. A.; Bertaux, J. -L.; Bertini, I.; Da Deppo, V.; Davidsson, B.;
   Debei, S.; De Cecco, M.; Fornasier, S.; Fulle, M.; Groussin, O.;
   Gutierrez, P. J.; Güttler, C.; Hviid, S. F.; Ip, W. -H.; Knollenberg,
   J.; Kramm, J. -R.; Kührt, E.; Küppers, M.; Lara, L. M.; Lazzarin, M.;
   Lopez Moreno, J. J.; Marzari, F.; Mottola, S.; Naletto, G.; Preusker,
   F.; Scholten, F.; Thomas, N.; Tubiana, C.; Vincent, J. -B.
2016A&A...585L...1L    Altcode:
  Context. On 12 November 2014, the European mission Rosetta delivered
  the Philae lander on the nucleus of comet 67P/Churyumov-Gerasimenko
  (67P). After the first touchdown, the lander bounced three times before
  finally landing at a site named Abydos. <BR /> Aims: We provide a
  morphologically detailed analysis of the Abydos landing site to support
  Philae's measurements and to give context for the interpretation of
  the images coming from the Comet Infrared and Visible Analyser (CIVA)
  camera system onboard the lander. <BR /> Methods: We used images
  acquired by the OSIRIS Narrow Angle Camera (NAC) on 6 December 2014
  to perform the analysis of the Abydos landing site, which provided the
  geomorphological map, the gravitational slope map, the size-frequency
  distribution of the boulders. We also computed the albedo and spectral
  reddening maps. <BR /> Results: The morphological analysis of the region
  could suggest that Philae is located on a primordial terrain. The Abydos
  site is surrounded by two layered and fractured outcrops and presents
  a 0.02 km<SUP>2</SUP> talus deposit rich in boulders. The boulder size
  frequency distribution gives a cumulative power-law index of -4.0 +
  0.3/-0.4, which is correlated with gravitational events triggered by
  sublimation and/or thermal fracturing causing regressive erosion. The
  average value of the albedo is 5.8% at λ<SUB>1</SUB> = 480.7 nm and
  7.4% at λ<SUB>2</SUB> = 649.2 nm, which is similar to the global
  albedos derived by OSIRIS and CIVA, respectively.

---------------------------------------------------------
Title: Sample of high-priority science objectives for future
    interplanetary missions towards asteroids
Authors: Vernazza, Pierre; Beck, Pierre; Lamy, Philippe;
   Guilbert-Lepoutre, Aurelie
2016RoAJ...26...35V    Altcode:
  In this paper, we present a sample of high-priority science objectives
  for future interplanetary missions towards asteroids that were submitted
  to ESA as a white paper in 2013

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Title: Sunset jets observed on comet 67P/Churyumov-Gerasimenko
    sustained by subsurface thermal lag
Authors: Shi, X.; Hu, X.; Sierks, H.; Güttler, C.; A'Hearn, M.; Blum,
   J.; El-Maarry, M. R.; Kührt, E.; Mottola, S.; Pajola, M.; Oklay, N.;
   Fornasier, S.; Tubiana, C.; Keller, H. U.; Vincent, J. -B.; Bodewits,
   D.; Höfner, S.; Lin, Z. -Y.; Gicquel, A.; Hofmann, M.; Barbieri,
   C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; Barucci,
   M. A.; Bertaux, J. -L.; Bertini, I.; Cremonese, G.; Da Deppo, V.;
   Davidsson, B.; Debei, S.; De Cecco, M.; Fulle, M.; Groussin, O.;
   Gutiérrez, P. J.; Hviid, S. F.; Ip, W. -H.; Jorda, L.; Knollenberg,
   J.; Kovacs, G.; Kramm, J. -R.; Küppers, M.; Lara, L. M.; Lazzarin,
   M.; Lopez-Moreno, J. J.; Marzari, F.; Naletto, G.; Thomas, N.
2016A&A...586A...7S    Altcode:
  We present observations of sunset jets on comet
  67P/Churyumov-Gerasimenko by Rosetta/OSIRIS camera. In late April 2015,
  when the comet was at a heliocentric distance of ~1.8 AU, clusters of
  dust jets that originated in the Ma'at region on the comet's small lobe
  were identified from multipleimages and were apparently sustained for
  about an hour beyond local sunset. Emanating from the shadowed nucleus,
  these jets became visible by solar illumination at their apparent
  sources up to only a few tens of meters above the nucleus surface. We
  investigate the plausibility of these jets as having been triggered by
  water ice sublimation and sustained by thermal lag in the subsurface
  beyond sunset. A general thermo-physical model was parameterized such
  that the thermal lag in the subsurface is consistent with the elapsed
  time of observation after sunset. It is found that the sublimation
  of water ice from a depth of 6 mm and with a low thermal inertia of
  50 W m<SUP>-2</SUP> K<SUP>-1</SUP> s<SUP>1/2</SUP> could explain the
  spatial pattern and evolution of the apparent sources, particularly
  their disappearance due to the eventual cooling of the subsurface. Our
  analysis suggests that these sunset jets were essentially day-side
  dust activities that continued after sunset. Specific observational
  conditions for the sunset jets constrain their possible sources to
  mostly within the less abrupt, dusty terrains. The uneven distribution
  of these jets is possibly related to subsurface inhomogeneities in
  the dusty area.

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Title: Coma dust environment observed by GIADA during the Perihelion
    of 67P/Churyumov-Gerasimenko.
Authors: Rotundi, A.; Della Corte, V.; Fulle, M.; Ferrari, M.;
   Ivanovski, S. L.; Sordini, R.; Mazzotta Epifani, E.; Palumbo, P.;
   Colangeli, L.; Lopez-Moreno, J. J.; Rodriguez, J.; Zakharov, V.;
   Bussoletti, E.; Crifo, J. F.; Esposito, F.; Green, S.; Gruen, E.;
   Lamy, P. L.; McDonnell, T.; Mennella, V.; Molina, A.; Moreno, F.;
   Ortiz, J. L.; Palomba, E.; Perrin, J. M.; Rodrigo, R.; Weissman,
   P. R.; Zarnecki, J.; Cosi, M.; Giovane, F.; Gustafson, B.; Herranz,
   M.; Jeronimo, J. M.; Leese, M.; Lopez-Jimenez, A.; Morales, R.
2015AGUFM.P33E..05R    Altcode:
  GIADA (Grain Impact Analyzer and Dust Accumulator) is an in-situ
  instrument mounted onboard Rosetta monitoring the dust environment of
  comet 67P/Churyumov-Gerasimenko. GIADA is composed of 3 sub-systems: 1)
  the Grain Detection System, based on particle detection through light
  scattering; 2) the Impact Sensor, giving momentum measurement; 3) the
  Micro-Balances System, constituted of 5 quartz crystal microbalances,
  giving cumulative deposited dust. The combination of the measurements
  performed by these 3 subsystems provides: the number, the mass,
  the momentum and the speed distribution of dust particles emitted
  from the comet nucleus. We will present the coma dust environment as
  observed by GIADA during the perihelion phase of the Rosetta space
  mission. Despite the large distance from the nucleus, more than 200 km,
  GIADA was able to detect temporal and spatial variation of dust density
  distribution. Specific high dust spatial density sectors of the coma
  have been identified and their evolution during the perihelion phase
  was studied. Acknowledgements. GIADA was built by a consortium led
  by the Univ. Napoli "Parthenope" &amp; INAF- Oss. Astr. Capodimonte,
  IT, in collaboration with the Inst. de Astrofisica de Andalucia,
  ES, Selex-ES s.p.a. and SENER. GIADA is presently managed &amp;
  operated by Ist. di Astrofisica e Planetologia Spaziali-INAF,
  IT. GIADA was funded and managed by the Agenzia Spaziale Italiana,
  IT, with a support of the Spanish Ministry of Education and Science
  MEC, ES. GIADA was developped from a PI proposal supported by the
  University of Kent; sci. &amp; tech. contribution given by CISAS,
  IT, Lab. d'Astr. Spat., FR, and Institutions from UK, IT, FR, DE and
  USA. We thank the RSGS/ESAC, RMOC/ESOC &amp; Rosetta Project/ESTEC for
  their outstanding work. Science support provided by NASA through the US
  Rosetta Project managed by JPL/California Institute of Technology. GIADA
  calibrated data will be available through the ESA's PSA web site.

---------------------------------------------------------
Title: Morphology of the nucleus of Comet 67P/Churyumov--Gerasimenko
    from stereo and high spatial resolution OSIRIS-NAC images
Authors: Lamy, P. L.; Groussin, O.; Romeuf, D.; Auger, A. T.; Jorda,
   L.; Capanna, C.; Faury, G.
2015AGUFM.P31E2113L    Altcode:
  The Narrow Angle Camera (NAC) of the OSIRIS imaging system aboard ESA's
  Rosetta spacecraft has acquired images of the surface of the nucleus
  of comet 67P/Churyumov-Gerasimenko at scales down to 0.2 m/pixel. We
  employ a variety of techniques to characterize its morphology. Digital
  terrain modeling (DTM), indispensable for quantitative morphological
  analysis is performed using stereophotoclinometry (SPC). Depending
  upon the observational coverage, the resolution of the DTMs exceeds
  1 m in the most favorable cases. The ultimate stereographic analysis
  is performed by exploiting pairs of images able to produce anaglyphs
  whose spatial resolution surpasses that of the DTMs. Digital image
  filtering and contrast enhancement techniques are applied on the
  original images as appropriate. We first concentrate on the dust
  covered terrains possibly resulting from airfall deposits, on the
  quasi circular depressions or basins possibly connected to collapses
  of the underground terrain, and on large scarps that suggest extensive
  mass disruption. We pay special attention to lithologies that may
  give clues to the subsurface structure of the nucleus. Our ultimate
  goal is to understand the processes at work on the nucleus, directly
  or indirectly connected to its activity as there appears to a variety
  of processes far beyond what was classically considered in the past,
  for instance airfall deposits, surface dust transport, mass wasting,
  and insolation weathering.

---------------------------------------------------------
Title: The Subsurface Structure and Density of Cometary Nuclei
Authors: Lamy, P. L.; Herique, A.; Toth, I.
2015SSRv..197...85L    Altcode: 2015SSRv..tmp...33L
  Little is known about the internal structure and density of cometary
  nuclei. Indirect evidences available so far are not compelling and these
  questions essentially remain a matter of speculation. It is therefore
  important to fully exploit the potential sources of information and
  this is particularly the case of radar observations which have the
  capability to probe the first few meters of cometary nuclei when they
  come sufficiently close to Earth. We review the available results
  and find that proper data are available for eight nuclei yielding
  their geometric radar albedo and the dielectric permittivity of
  their subsurface assuming that the scattering of the radar beam is
  predominantly specular. The range of permittivity is quite broad,
  extending from 1.7 to 3.1 although a more realistic interval is
  probably 2 to 3.1 implying pronounced diversity in the subsurface
  properties of cometary nuclei. A novel interpretation of these results
  is performed based on the calculation of the dielectric permittivity
  of various samples of three-phase mixtures of ice, dust and vacuum
  using two mixing formulas and on the introduction of ternary diagrams
  where the three axes correspond to the volumetric fraction of the three
  phases. The derived values of the permittivity supplemented by a general
  constraint on the dust-to-ice mass ratio define restricted regions in
  the ternary diagrams broadly imposing that the ice fraction lies in
  the range 0.1 to 0.2, the dust fraction in the range 0.2 to 0.5, and
  the porosity in the range 35 % to 75 %. The density of the subsurface
  of the considered eight nuclei is only constrained to the broad range
  500 to 2000 kg m<SUP>-3</SUP> due to the poorly known density of the
  dust phase. However, the results unambiguously reveal considerable
  variation among cometary nuclei of the structure and properties of
  their subsurface layers.

---------------------------------------------------------
Title: The Activity of Comet 67P/Churyumov-Gerasimenko as Seen by
    Rosetta/OSIRIS
Authors: Sierks, H.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Rickman,
   H.; Koschny, D.
2015AGUFM.P33E..02S    Altcode:
  The Rosetta mission of the European Space Agency arrived on August 6,
  2014, at the target comet 67P/Churyumov-Gerasimenko. OSIRIS (Optical,
  Spectroscopic, and Infrared Remote Imaging System) is the scientific
  imaging system onboard Rosetta. OSIRIS consists of a Narrow Angle Camera
  (NAC) for the nucleus surface and dust studies and a Wide Angle Camera
  (WAC) for the wide field gas and dust coma investigations. OSIRIS
  observed the coma and the nucleus of comet 67P/C-G during approach,
  arrival, and landing of PHILAE. OSIRIS continued comet monitoring and
  mapping of surface and activity in 2015 with close fly-bys with high
  resolution and remote, wide angle observations. The scientific results
  reveal a nucleus with two lobes and varied morphology. Active regions
  are located at steep cliffs and collapsed pits which form collimated gas
  jets. Dust is accelerated by the gas, forming bright jet filaments and
  the large scale, diffuse coma of the comet. We will present activity
  and surface changes observed in the Northern and Southern hemisphere
  and around perihelion passage.

---------------------------------------------------------
Title: Subsurface characterization of 67P/Churyumov-Gerasimenko's
    Abydos Site
Authors: Brugger, B.; Mousis, O.; Morse, A.; Marboeuf, U.; Jorda, L.;
   Guilbert-Lepoutre, A.; Andrews, D.; Barber, S.; Lamy, P.; Luspay-Kuti,
   A.; Mandt, K.; Morgan, G.; Sheridan, S.; Vernazza, P.; Wright, I. P.
2015sf2a.conf...53B    Altcode:
  We investigate the subsurface structure of comet
  67P/Churyumov-Gerasimenko at the landing site of Rosetta's descent
  module Philae. We use a cometary nucleus model with an optimized
  parametrization and assume an initial composition derived from
  Rosetta/ROSINA measurements. We compare the CO and CO_2 outgassing
  rates derived from our model with those measured in situ by the Ptolemy
  experiment aboard the Philae module on November 12, 2014. We find
  results that allow us to place two main constraints on the subsurface
  structure of this region: a low CO/CO_2 molar ratio is needed in the
  nucleus, and the dust/ice mass ratio is higher at Abydos than in the
  rest of the nucleus. These specific constraints on Abydos support the
  statement of an important heterogeneity in 67P/Churyumov-Gerasimenko's
  nucleus.

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Title: The primordial nucleus of Comet 67P/Churyumov-Gerasimenko
Authors: Davidsson, Bjorn; Sierks, Holger; Guettler, Carsten; Marzari,
   Francesco; Pajola, Maurizio; Rickman, Hans; A'Hearn, Michael; Auger,
   Anne-Therese; El-Maarry, Mohamed; Fornasier, Sonia; Gutierrez, Pedro;
   Keller, Horst Uwe; Massironi, Matteo; Snodgrass, Colin; Vincent,
   Jean-Baptiste; Barbieri, Cesare; Lamy, Philippe; Rodrigo, Rafael;
   Koschny, Detlef; Barucci, Antonella; Bertaux, Jean-Loup; Bertini,
   Ivano; Cremonese, Gabriele; Da Deppo, Vania; Debei, Stefano; De Cecco,
   Mariolino; Feller, Clement; Fulle, Marco; Groussin, Olivier; Hviid,
   Stubbe; Hoefner, Sebastian; Ip, Wing-Huen; Jorda, Laurent; Knollenberg,
   Joerg; Kovacs, Gabor; Kramm, Joerg-Rainer; Kuehrt, Ekkehard; Kueppers,
   Michael; La Forgia, Fiorangela; Lara, Luisa; Lazzarin, Monica; Lopez
   Moreno, Jose; Moissl-Fraund, Richard; Mottola, Stefano; Naletto,
   Giampiero; Oklay, Nilda; Thomas, Nicolas; Tubiana, Cecilia
2015DPS....4741315D    Altcode:
  Observations of Comet 67P/Churyumov-Gerasimenko by Rosetta show
  that the nucleus is bi-lobed, extensively layered, has a low bulk
  density, a high dust-to-ice mass ratio (implying high porosity),
  and weak strength except for a thin sintered surface layer. The comet
  is rich in supervolatiles (CO, CO2, N2), may contain amorphous water
  ice, and displays little to no signs of aqueous alteration. Lack of
  phyllosilicates in Stardust samples from Comet 81P/Wild 2 provides
  further support that comet nuclei did not contain liquid water.These
  properties differ from those expected for 50-200 km diameter bodies
  in the primordial disk. We find that thermal processing due to
  Al-26, combined with collisional compaction, creates a population
  of medium-sized bodies that are comparably dense, compacted,
  strong, heavily depleted in supervolatiles, containing little to no
  amorphous water ice, and that have experienced extensive aqueous
  alteration. Irregular satellites Phoebe and Himalia are potential
  representatives of this population. Collisional rubble piles inherit
  these properties from their parents. We therefore conclude that observed
  comet nuclei are primordial rubble piles, and not collisional rubble
  piles.We propose a concurrent comet and TNO formation scenario that
  is consistent with these observations. We argue that TNOs form due
  to streaming instabilities at sizes of about 50-400 km and that about
  350 of these grow slowly in a low-mass primordial disk to the size of
  Triton, causing little viscous stirring during growth. We propose a
  dynamically cold primordial disk, that prevents medium-sized TNOs from
  breaking into collisional rubble piles, and allows for the survival of
  primordial rubble-pile comets. We argue that comets form by hierarchical
  agglomeration out of material that remains after TNO formation. This
  slow growth is necessary to avoid thermal processing by Al-26, and to
  allow comet nuclei to incorporate 3 Myr old material from the inner
  Solar System, found in Stardust samples. Growth in the Solar Nebula
  creates porous single-lobe nuclei, while continued growth in a mildly
  viscously stirred primordial disk creates denser outer layers, and
  allow bi-lobe nucleus formation through mergers.

---------------------------------------------------------
Title: Temporal morphological changes at the surface of comet
    67P/Churyumov-Gerasimenko
Authors: Groussin, Olivier; Sierks, H.; Barbieri, C.; Lamy, P.;
   Rodrigo, R.; Koschny, D.; Rickman, H.; Keller, H. U.
2015DPS....4750005G    Altcode:
  A key scientific question, to understand how comets work and whether
  they still contain pristine materials at or near their surface,
  is to understand how the nucleus is changing with time and to which
  extent activity modifies its surface. Rosetta, which has been orbiting
  comet 67P/Churyumov-Gerasimenko since August 2014, offers a unique
  opportunity to tackle this fundamental question. Here, we report on
  temporal morphological changes detected on the surface of the nucleus
  of comet 67P by the OSIRIS cameras. Changes have been detected in
  several regions and in particular in the Imhotep region, where they are
  visible in the form of roundish features that are growing in size from
  a given location in a preferential direction. Terrains bluer than the
  surroundings appear during changes, suggesting the presence of (water)
  ice exposed on the surface.

---------------------------------------------------------
Title: Pits Formation from Volatile Outgassing on
    67P/Churyumov-Gerasimenko
Authors: Mousis, O.; Guilbert-Lepoutre, A.; Brugger, B.; Jorda, L.;
   Kargel, J. S.; Bouquet, A.; Auger, A. -T.; Lamy, P.; Vernazza, P.;
   Thomas, N.; Sierks, H.
2015ApJ...814L...5M    Altcode: 2015arXiv151007671M
  We investigate the thermal evolution of comet
  67P/Churyumov-Gerasimenko’s subsurface in the Seth_01 region,
  where active pits have been observed by the ESA/Rosetta mission. Our
  simulations show that clathrate destabilization and amorphous ice
  crystallization can occur at depths corresponding to those of the
  observed pits in a timescale shorter than 67P/Churyumov-Gerasimenko’s
  lifetime in the comet’s activity zone in the inner solar
  system. Sublimation of crystalline ice down to such depths is possible
  only in the absence of a dust mantle, which requires the presence of
  dust grains in the matrix small enough to be dragged out by gas from the
  pores. Our results are consistent with both pits formation via sinkholes
  or subsequent to outbursts, the dominant process depending on the status
  of the subsurface porosity. A sealed dust mantle would favor episodic
  and disruptive outgassing as a result of increasing gas pressure in
  the pores, while high porosity should allow the formation of large
  voids in the subsurface due to the continuous escape of volatiles. We
  finally conclude that the subsurface of 67P/Churyumov-Gerasimenko is
  not uniform at a spatial scale of ∼100-200 m.

---------------------------------------------------------
Title: Size-frequency distribution of boulders ≥7 m on comet
    67P/Churyumov-Gerasimenko
Authors: Pajola, Maurizio; Vincent, Jean-Baptiste; Güttler, Carsten;
   Lee, Jui-Chi; Bertini, Ivano; Massironi, Matteo; Simioni, Emanuele;
   Marzari, Francesco; Giacomini, Lorenza; Lucchetti, Alice; Barbieri,
   Cesare; Cremonese, Gabriele; Naletto, Giampiero; Pommerol, Antoine;
   El-Maarry, Mohamed R.; Besse, Sébastien; Küppers, Michael; La
   Forgia, Fiorangela; Lazzarin, Monica; Thomas, Nicholas; Auger,
   Anne-Thérèse; Sierks, Holger; Lamy, Philippe; Rodrigo, Rafael;
   Koschny, Detlef; Rickman, Hans; Keller, Horst U.; Agarwal, Jessica;
   A'Hearn, Michael F.; Barucci, Maria A.; Bertaux, Jean-Loup; Da
   Deppo, Vania; Davidsson, Björn; De Cecco, Mariolino; Debei, Stefano;
   Ferri, Francesca; Fornasier, Sonia; Fulle, Marco; Groussin, Olivier;
   Gutierrez, Pedro J.; Hviid, Stubbe F.; Ip, Wing-Huen; Jorda, Laurent;
   Knollenberg, Jörg; Kramm, J. -Rainer; Kürt, Ekkehard; Lara, Luisa M.;
   Lin, Zhong-Yi; Lopez Moreno, Jose J.; Magrin, Sara; Marchi, Simone;
   Michalik, Harald; Moissl, Richard; Mottola, Stefano; Oklay, Nilda;
   Preusker, Frank; Scholten, Frank; Tubiana, Cecilia
2015A&A...583A..37P    Altcode:
  <BR /> Aims: We derive for the first time the size-frequency
  distribution of boulders on a comet, 67P/Churyumov-Gerasimenko (67P),
  computed from the images taken by the Rosetta/OSIRIS imaging system. We
  highlight the possible physical processes that lead to these boulder
  size distributions. <BR /> Methods: We used images acquired by the
  OSIRIS Narrow Angle Camera, NAC, on 5 and 6 August 2014. The scale
  of these images (2.44-2.03 m/px) is such that boulders ≥7 m can
  be identified and manually extracted from the datasets with the
  software ArcGIS. We derived both global and localized size-frequency
  distributions. The three-pixel sampling detection, coupled with the
  favorable shadowing of the surface (observation phase angle ranging
  from 48° to 53°), enables unequivocally detecting boulders scattered
  all over the illuminated side of 67P. <BR /> Results: We identify 3546
  boulders larger than 7 m on the imaged surface (36.4 km<SUP>2</SUP>),
  with a global number density of nearly 100/km<SUP>2</SUP> and a
  cumulative size-frequency distribution represented by a power-law
  with index of -3.6 +0.2/-0.3. The two lobes of 67P appear to have
  slightly different distributions, with an index of -3.5 +0.2/-0.3
  for the main lobe (body) and -4.0 +0.3/-0.2 for the small lobe
  (head). The steeper distribution of the small lobe might be due to a
  more pervasive fracturing. The difference of the distribution for the
  connecting region (neck) is much more significant, with an index value
  of -2.2 +0.2/-0.2. We propose that the boulder field located in the
  neck area is the result of blocks falling from the contiguous Hathor
  cliff. The lower slope of the size-frequency distribution we see today
  in the neck area might be due to the concurrent processes acting on
  the smallest boulders, such as i) disintegration or fragmentation and
  vanishing through sublimation; ii) uplifting by gas drag and consequent
  redistribution; and iii) burial beneath a debris blanket. We also
  derived the cumulative size-frequency distribution per km<SUP>2</SUP>
  of localized areas on 67P. By comparing the cumulative size-frequency
  distributions of similar geomorphological settings, we derived similar
  power-law index values. This suggests that despite the selected
  locations on different and often opposite sides of the comet, similar
  sublimation or activity processes, pit formation or collapses, as well
  as thermal stresses or fracturing events occurred on multiple areas
  of the comet, shaping its surface into the appearance we see today.

---------------------------------------------------------
Title: Regional surface morphology of comet 67P/Churyumov-Gerasimenko
    from Rosetta/OSIRIS images
Authors: El-Maarry, M. R.; Thomas, N.; Giacomini, L.; Massironi, M.;
   Pajola, M.; Marschall, R.; Gracia-Berná, A.; Sierks, H.; Barbieri,
   C.; Lamy, P. L.; Rodrigo, R.; Rickman, H.; Koschny, D.; Keller,
   H. U.; Agarwal, J.; A'Hearn, M. F.; Auger, A. -T.; Barucci, M. A.;
   Bertaux, J. -L.; Bertini, I.; Besse, S.; Bodewits, D.; Cremonese, G.;
   Da Deppo, V.; Davidsson, B.; De Cecco, M.; Debei, S.; Güttler, C.;
   Fornasier, S.; Fulle, M.; Groussin, O.; Gutierrez, P. J.; Hviid, S. F.;
   Ip, W. -H.; Jorda, L.; Knollenberg, J.; Kovacs, G.; Kramm, J. -R.;
   Kührt, E.; Küppers, M.; La Forgia, F.; Lara, L. M.; Lazzarin, M.;
   Lopez Moreno, J. J.; Marchi, S.; Marzari, F.; Michalik, H.; Naletto,
   G.; Oklay, N.; Pommerol, A.; Preusker, F.; Scholten, F.; Tubiana,
   C.; Vincent, J. -B.
2015A&A...583A..26E    Altcode:
  <BR /> Aims: The OSIRIS camera onboard the Rosetta spacecraft
  has been acquiring images of the comet 67P/Churyumov-Gerasimenko
  (67P)'s nucleus at spatial resolutions down to ~0.17 m/px ever since
  Aug. 2014. These images have yielded unprecedented insight into the
  morphological diversity of the comet's surface. This paper presents
  an overview of the regional morphology of comet 67P. <BR /> Methods:
  We used the images that were acquired at orbits ~20-30 km from the
  center of the comet to distinguish different regions on the surface
  and introduce the basic regional nomenclature adopted by all papers
  in this Rosetta special feature that address the comet's morphology
  and surface processes. We used anaglyphs to detect subtle regional and
  topographical boundaries and images from close orbit (~10 km from the
  comet's center) to investigate the fine texture of the surface. <BR />
  Results: Nineteen regions have currently been defined on the nucleus
  based on morphological and/or structural boundaries, and they can be
  grouped into distinctive region types. Consolidated, fractured regions
  are the most common region type. Some of these regions enclose smooth
  units that appear to settle in gravitational sinks or topographically
  low areas. Both comet lobes have a significant portion of their surface
  covered by a dusty coating that appears to be recently placed and shows
  signs of mobilization by aeolian-like processes. The dusty coatings
  cover most of the regions on the surface but are notably absent from
  a couple of irregular large depressions that show sharp contacts with
  their surroundings and talus-like deposits in their interiors, which
  suggests that short-term explosive activity may play a significant role
  in shaping the comet's surface in addition to long-term sublimation
  loss. Finally, the presence of layered brittle units showing signs
  of mechanical failure predominantly in one of the comet's lobes
  can indicate a compositional heterogeneity between the two lobes. <P
  />Tables 2 and 3 and Appendix A are available in electronic form at <A
  href="http://www.aanda.org/10.1051/0004-6361/201525723/olm">http://www.aanda.org</A>

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Title: Orbital elements of the material surrounding comet
    67P/Churyumov-Gerasimenko
Authors: Davidsson, B. J. R.; Gutiérrez, P. J.; Sierks, H.; Barbieri,
   C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller,
   H. U.; Agarwal, J.; A'Hearn, M. F.; Barucci, M. A.; Bertaux, J. -L.;
   Bertini, I.; Bodewits, D.; Cremonese, G.; Da Deppo, V.; Debei, S.;
   De Cecco, M.; Fornasier, S.; Fulle, M.; Groussin, O.; Güttler, C.;
   Hviid, S. F.; Ip, W. -H.; Jorda, L.; Knollenberg, J.; Kovacs, G.;
   Kramm, J. -R.; Kührt, E.; Küppers, M.; La Forgia, F.; Lara, L. M.;
   Lazzarin, M.; Lopez Moreno, J. J.; Lowry, S.; Magrin, S.; Marzari,
   F.; Michalik, H.; Moissl-Fraund, R.; Naletto, G.; Oklay, N.; Pajola,
   M.; Snodgrass, C.; Thomas, N.; Tubiana, C.; Vincent, J. -B.
2015A&A...583A..16D    Altcode:
  Context. We investigate the dust coma within the Hill sphere of comet
  67P/Churyumov-Gerasimenko. <BR /> Aims: We aim to determine osculating
  orbital elements for individual distinguishable but unresolved
  slow-moving grains in the vicinity of the nucleus. In addition,
  we perform photometry and constrain grain sizes. <BR /> Methods: We
  performed astrometry and photometry using images acquired by the OSIRIS
  Wide Angle Camera on the European Space Agency spacecraft Rosetta. Based
  on these measurements, we employed standard orbit determination
  and orbit improvement techniques. <BR /> Results: Orbital elements
  and effective diameters of four grains were constrained, but we were
  unable to uniquely determine them. Two of the grains have light curves
  that indicate grain rotation. <BR /> Conclusions: The four grains have
  diameters nominally in the range 0.14-0.50 m. For three of the grains,
  we found elliptic orbits, which is consistent with a cloud of bound
  particles around the nucleus. However, hyperbolic escape trajectories
  cannot be excluded for any of the grains, and for one grain this is
  the only known option. One grain may have originated from the surface
  shortly before observation. These results have possible implications
  for the understanding of the dispersal of the cloud of bound debris
  around comet nuclei, as well as for understanding the ejection of
  large grains far from the Sun.

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Title: Geomorphology of the Imhotep region on comet
    67P/Churyumov-Gerasimenko from OSIRIS observations
Authors: Auger, A. -T.; Groussin, O.; Jorda, L.; Bouley, S.; Gaskell,
   R.; Lamy, P. L.; Capanna, C.; Thomas, N.; Pommerol, A.; Sierks, H.;
   Barbieri, C.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller, H. U.;
   Agarwal, J.; A'Hearn, M. F.; Barucci, M. A.; Bertaux, J. -L.; Bertini,
   I.; Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco,
   M.; El-Maarry, M. R.; Fornasier, S.; Fulle, M.; Gutiérrez, P. J.;
   Güttler, C.; Hviid, S.; Ip, W. -H.; Knollenberg, J.; Kramm, J. -R.;
   Kührt, E.; Küppers, M.; La Forgia, F.; Lara, L. M.; Lazzarin,
   M.; Lopez Moreno, J. J.; Marchi, S.; Marzari, F.; Massironi, M.;
   Michalik, H.; Naletto, G.; Oklay, N.; Pajola, M.; Sabau, L.; Tubiana,
   C.; Vincent, J. -B.; Wenzel, K. -P.
2015A&A...583A..35A    Altcode:
  Context. Since August 2014, the OSIRIS Narrow Angle Camera (NAC) onboard
  the Rosetta spacecraft has acquired high spatial resolution images of
  the nucleus of comet 67P/Churyumov-Gerasimenko, down to the decimeter
  scale. This paper focuses on the Imhotep region, located on the largest
  lobe of the nucleus, near the equator. <BR /> Aims: We map, inventory,
  and describe the geomorphology of the Imhotep region. We propose and
  discuss some processes to explain the formation and ongoing evolution of
  this region. <BR /> Methods: We used OSIRIS NAC images, gravitational
  heights and slopes, and digital terrain models to map and measure the
  morphologies of Imhotep. <BR /> Results: The Imhotep region presents a
  wide variety of terrains and morphologies: smooth and rocky terrains,
  bright areas, linear features, roundish features, and boulders. Gravity
  processes such as mass wasting and collapse play a significant role
  in the geomorphological evolution of this region. Cometary processes
  initiate erosion and are responsible for the formation of degassing
  conduits that are revealed by elevated roundish features on the
  surface. We also propose a scenario for the formation and evolution
  of the Imhotep region; this implies the presence of large primordial
  voids inside the nucleus, resulting from its formation process.

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Title: Geomorphology and spectrophotometry of Philae's landing site
    on comet 67P/Churyumov-Gerasimenko
Authors: La Forgia, F.; Giacomini, L.; Lazzarin, M.; Massironi, M.;
   Oklay, N.; Scholten, F.; Pajola, M.; Bertini, I.; Cremonese, G.;
   Barbieri, C.; Naletto, G.; Simioni, E.; Preusker, F.; Thomas, N.;
   Sierks, H.; Lamy, P.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller,
   H. U.; Agarwal, J.; Auger, A. -T.; A'Hearn, M. F.; Barucci, M. A.;
   Bertaux, J. -L.; Besse, S.; Bodewits, D.; Da Deppo, V.; Davidsson, B.;
   Debei, S.; De Cecco, M.; El-Maarry, M. R.; Ferri, F.; Fornasier, S.;
   Fulle, M.; Groussin, O.; Gutiérrez, P. J.; Güttler, C.; Hall, I.;
   Hviid, S. F.; Ip, W. -H.; Jorda, L.; Knollenberg, J.; Kramm, J. R.;
   Kührt, E.; Küppers, M.; Lara, L. -M.; Lopez Moreno, J. J.; Magrin,
   S.; Marzari, F.; Michalik, H.; Mottola, S.; Pommerol, A.; Tubiana,
   C.; Vincent, J. -B.
2015A&A...583A..41L    Altcode:
  Context. On 12 November 2014 the European mission Rosetta succeeded
  in delivering a lander, named Philae, on the surface of one of
  the smallest, low-gravity and most primitive bodies of the solar
  system, the comet 67P/Churyumov-Gerasimenko (67P). <BR /> Aims:
  The aim of this paper is to provide a comprehensive geomorphological
  and spectrophotometric analysis of Philae's landing site (Agilkia)
  to give an essential framework for the interpretation of its in situ
  measurements. <BR /> Methods: OSIRIS images, coupled with gravitational
  slopes derived from the 3D shape model based on stereo-photogrammetry
  were used to interpret the geomorphology of the site. We adopted the
  Hapke model, using previously derived parameters, to photometrically
  correct the images in orange filter (649.2 nm). The best approximation
  to the Hapke model, given by the Akimov parameter-less function,
  was used to correct the reflectance for the effects of viewing and
  illumination conditions in the other filters. Spectral analyses on
  coregistered color cubes were used to retrieve spectrophotometric
  properties. <BR /> Results: The landing site shows an average normal
  albedo of 6.7% in the orange filter with variations of ~15% and a global
  featureless spectrum with an average red spectral slope of 15.2%/100
  nm between 480.7 nm (blue filter) and 882.1 nm (near-IR filter). The
  spatial analysis shows a well-established correlation between the
  geomorphological units and the photometric characteristics of the
  surface. In particular, smooth deposits have the highest reflectance
  a bluer spectrum than the outcropping material across the area. <BR
  /> Conclusions: The featureless spectrum and the redness of the
  material are compatible with the results by other instruments that
  have suggested an organic composition. The observed small spectral
  variegation could be due to grain size effects. However, the combination
  of photometric and spectral variegation suggests that a compositional
  differentiation is more likely. This might be tentatively interpreted
  as the effect of the efficient dust-transport processes acting on
  67P. High-activity regions might be the original sources for smooth
  fine-grained materials that then covered Agilkia as a consequence of
  airfall of residual material. More observations performed by OSIRIS
  as the comet approaches the Sun would help interpreting the processes
  that work at shaping the landing site and the overall nucleus.

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Title: Shape model, reference system definition, and cartographic
    mapping standards for comet 67P/Churyumov-Gerasimenko -
    Stereo-photogrammetric analysis of Rosetta/OSIRIS image data
Authors: Preusker, F.; Scholten, F.; Matz, K. -D.; Roatsch, T.;
   Willner, K.; Hviid, S. F.; Knollenberg, J.; Jorda, L.; Gutiérrez,
   P. J.; Kührt, E.; Mottola, S.; A'Hearn, M. F.; Thomas, N.; Sierks,
   H.; Barbieri, C.; Lamy, P.; Rodrigo, R.; Koschny, D.; Rickman, H.;
   Keller, H. U.; Agarwal, J.; Barucci, M. A.; Bertaux, J. -L.; Bertini,
   I.; Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco,
   M.; Fornasier, S.; Fulle, M.; Groussin, O.; Güttler, C.; Ip, W. -H.;
   Kramm, J. R.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Lopez Moreno,
   J. J.; Marzari, F.; Michalik, H.; Naletto, G.; Oklay, N.; Tubiana,
   C.; Vincent, J. -B.
2015A&A...583A..33P    Altcode:
  We analyzed more than 200 OSIRIS NAC images with a pixel scale of
  0.9-2.4 m/pixel of comet 67P/Churyumov-Gerasimenko (67P) that have been
  acquired from onboard the Rosetta spacecraft in August and September
  2014 using stereo-photogrammetric methods (SPG). We derived improved
  spacecraft position and pointing data for the OSIRIS images and a
  high-resolution shape model that consists of about 16 million facets
  (2 m horizontal sampling) and a typical vertical accuracy at the
  decimeter scale. From this model, we derive a volume for the northern
  hemisphere of 9.35 km<SUP>3</SUP> ± 0.1 km<SUP>3</SUP>. With the
  assumption of a homogeneous density distribution and taking into
  account the current uncertainty of the position of the comet's
  center-of-mass, we extrapolated this value to an overall volume
  of18.7 km<SUP>3</SUP>± 1.2 km<SUP>3</SUP>, and, with a current best
  estimate of 1.0 × 10<SUP>13</SUP> kg for the mass, we derive a bulk
  density of 535 kg/m<SUP>3</SUP>± 35 kg/m<SUP>3</SUP>. Furthermore,
  we used SPG methods to analyze the rotational elements of 67P. The
  rotational period for August and September 2014 was determined to
  be 12.4041 ± 0.0004 h. For the orientation of the rotational axis
  (z-axis of the body-fixed reference frame) we derived a precession
  model with a half-cone angle of 0.14°, a cone center position at
  69.54°/64.11° (RA/Dec J2000 equatorial coordinates), and a precession
  period of 10.7 days. For the definition of zero longitude (x-axis
  orientation), we finally selected the boulder-like Cheops feature on
  the big lobe of 67P and fixed its spherical coordinates to 142.35°
  right-hand-rule eastern longitude and -0.28° latitude. This completes
  the definition of the new Cheops reference frame for 67P. Finally,
  we defined cartographic mapping standards for common use and combined
  analyses of scientific results that have been obtained not only
  within the OSIRIS team, but also within other groups of the Rosetta
  mission. <P />Appendices are available in electronic form at <A
  href="http://www.aanda.org/10.1051/0004-6361/201526349/olm">http://www.aanda.org</A>

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Title: Insolation, erosion, and morphology of comet
    67P/Churyumov-Gerasimenko
Authors: Keller, H. U.; Mottola, S.; Davidsson, B.; Schröder, S. E.;
   Skorov, Y.; Kührt, E.; Groussin, O.; Pajola, M.; Hviid, S. F.;
   Preusker, F.; Scholten, F.; A'Hearn, M. F.; Sierks, H.; Barbieri,
   C.; Lamy, P.; Rodrigo, R.; Koschny, D.; Rickman, H.; Barucci, M. A.;
   Bertaux, J. -L.; Bertini, I.; Cremonese, G.; Da Deppo, V.; Debei,
   S.; De Cecco, M.; Fornasier, S.; Fulle, M.; Gutiérrez, P. J.; Ip,
   W. -H.; Jorda, L.; Knollenberg, J.; Kramm, J. R.; Küppers, M.; Lara,
   L. M.; Lazzarin, M.; Lopez Moreno, J. J.; Marzari, F.; Michalik, H.;
   Naletto, G.; Sabau, L.; Thomas, N.; Vincent, J. -B.; Wenzel, K. -P.;
   Agarwal, J.; Güttler, C.; Oklay, N.; Tubiana, C.
2015A&A...583A..34K    Altcode:
  Context. The complex shape of comet 67P and its oblique rotation axis
  cause pronounced seasonal effects. Irradiation and hence activity vary
  strongly. <BR /> Aims: We investigate the insolation of the cometary
  surface in order to predict the sublimation of water ice. The strongly
  varying erosion levels are correlated with the topography and morphology
  of the present cometary surface and its evolution. <BR /> Methods: The
  insolation as a function of heliocentric distance and diurnal (spin
  dependent) variation is calculated using &gt;10<SUP>5</SUP> facets
  of a detailed digital terrain model. Shading, but also illumination
  and thermal radiation by facets in the field of view of a specific
  facet are iteratively taken into account. We use a two-layer model of
  a thin porous dust cover above an icy surface to calculate the water
  sublimation, presuming steady state and a uniform surface. Our second
  model, which includes the history of warming and cooling due to thermal
  inertia, is restricted to a much simpler shape model but allows us to
  test various distributions of active areas. <BR /> Results: Sublimation
  from a dirty ice surface yields maximum erosion. A thin dust cover
  of 50 μm yields similar rates at perihelion. Only about 6% of the
  surface needs to be active to match the observed water production rates
  at perihelion. A dust layer of 1 mm thickness suppresses the activity
  by a factor of 4 to 5. Erosion on the south side can reach more than
  10 m per orbit at active spots. The energy input to the concave neck
  area (Hapi) during northern summer is enhanced by about 50% owing to
  self-illumination. Here surface temperatures reach maximum values along
  the foot of the Hathor wall. Integrated over the whole orbit this area
  receives the least energy input. Based on the detailed shape model,
  the simulations identify "hot spots" in depressions and larger pits in
  good correlation with observed dust activity. Three-quarters of the
  total sublimation is produced while the sub-solar latitude is south,
  resulting in a distinct dichotomy in activity and morphology. <BR />
  Conclusions: The northern areas display a much rougher morphology
  than what is seen on Imhotep, an area at the equator that will be
  fully illuminated when 67P is closer to the Sun. Self-illumination
  in concave regions enhance the energy input and hence erosion. This
  explains the early activity observed at Hapi. Cliffs are more
  prone to erosion than horizontal, often dust covered, areas, which
  leads to surface planation. Local activity can only persist if the
  forming cliff walls are eroding. Comet 67P has two lobes and also two
  distinct sides. Transport of material from the south to the north is
  probable. The morphology of the Imhotep plain should be typical for
  the terrains of the yet unseen southern hemisphere.

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Title: Morphology and dynamics of the jets of comet
67P/Churyumov-Gerasimenko: Early-phase development
Authors: Lin, Z. -Y.; Ip, W. -H.; Lai, I. -L.; Lee, J. -C.; Vincent,
   J. -B.; Lara, L. M.; Bodewits, D.; Sierks, H.; Barbieri, C.; Lamy,
   P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller, H. U.; Agarwal,
   J.; A'Hearn, M. F.; Barucci, M. A.; Bertaux, J. -L.; Bertini, I.;
   Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco,
   M.; Fornasier, S.; Fulle, M.; Groussin, O.; Gutiérrez, P. J.;
   Güttler, C.; Hviid, S. F.; Jorda, L.; Knollenberg, J.; Kovacs, G.;
   Kramm, J. -R.; Kührt, E.; Küppers, M.; La Forgia, F.; Lazzarin, M.;
   López-Moreno, J. J.; Lowry, S.; Marzari, F.; Michalik, H.; Mottola,
   S.; Naletto, G.; Oklay, N.; Pajola, M.; Rożek, A.; Thomas, N.; Liao,
   Y.; Tubiana, C.
2015A&A...583A..11L    Altcode:
  <BR /> Aims: The OSIRIS camera onboard the Rosetta spacecraft obtained
  close-up views of the dust coma of comet 67P. The jet structures can be
  used to trace their source regions and to examine the possible effect
  of gas-surface interaction. <BR /> Methods: We analyzed the wide-angle
  images obtained in the special dust observation sequences between
  August and September 2014. The jet features detected in different
  images were compared to study their time variability. The locations
  of the potential source regions of some of the jets are identified
  by ray tracing. We used a ring-masking technique to calculate the
  brightness distribution of dust jets along the projected distance. <BR
  /> Results: The jets detected between August and September 2014 mostly
  originated in the Hapi region. Morphological changes appeared over
  a timescale of several days in September. The brightness slope of
  the dust jets is much steeper than the background coma. This might
  be related to the sublimation or fragmentation of the emitted dust
  grains. Interaction of the expanding gas flow with the cliff walls on
  both sides of Hapi could lead to erosion and material down-fall to the
  nucleus surface. <P />Appendix A is available in electronic form at <A
  href="http://www.aanda.org/10.1051/0004-6361/201525961/olm">http://www.aanda.org</A>

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Title: Redistribution of particles across the nucleus of comet
    67P/Churyumov-Gerasimenko
Authors: Thomas, N.; Davidsson, B.; El-Maarry, M. R.; Fornasier, S.;
   Giacomini, L.; Gracia-Berná, A. G.; Hviid, S. F.; Ip, W. -H.; Jorda,
   L.; Keller, H. U.; Knollenberg, J.; Kührt, E.; La Forgia, F.; Lai,
   I. L.; Liao, Y.; Marschall, R.; Massironi, M.; Mottola, S.; Pajola,
   M.; Poch, O.; Pommerol, A.; Preusker, F.; Scholten, F.; Su, C. C.;
   Wu, J. S.; Vincent, J. -B.; Sierks, H.; Barbieri, C.; Lamy, P. L.;
   Rodrigo, R.; Koschny, D.; Rickman, H.; A'Hearn, M. F.; Barucci,
   M. A.; Bertaux, J. -L.; Bertini, I.; Cremonese, G.; Da Deppo, V.;
   Debei, S.; de Cecco, M.; Fulle, M.; Groussin, O.; Gutierrez, P. J.;
   Kramm, J. -R.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Lopez Moreno,
   J. J.; Marzari, F.; Michalik, H.; Naletto, G.; Agarwal, J.; Güttler,
   C.; Oklay, N.; Tubiana, C.
2015A&A...583A..17T    Altcode:
  Context. We present an investigation of the surface properties of areas
  on the nucleus of comet 67P/Churyumov-Gerasimenko. <BR /> Aims: We aim
  to show that transport of material from one part of the cometary nucleus
  to another is a significant mechanism that influences the appearance
  of the nucleus and the surface thermal properties. <BR /> Methods: We
  used data from the OSIRIS imaging system onboard the Rosetta spacecraft
  to identify surface features on the nucleus that can be produced by
  various transport mechanisms. We used simple calculations based on
  previous works to establish the plausibility of dust transport from one
  part of the nucleus to another. <BR /> Results: We show by observation
  and modeling that "airfall" as a consequence of non-escaping large
  particles emitted from the neck region of the nucleus is a plausible
  explanation for the smooth thin deposits in the northern hemisphere
  of the nucleus. The consequences are also discussed. We also present
  observations of aeolian ripples and ventifacts. We show by numerical
  modeling that a type of saltation is plausible even under the rarified
  gas densities seen at the surface of the nucleus. However, interparticle
  cohesive forces present difficulties for this model, and an alternative
  mechanism for the initiation of reptation and creep may result from
  the airfall mechanism. The requirements on gas density and other
  parameters of this alternative make it a more attractive explanation
  for the observations. The uncertainties and implications are discussed.

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Title: Comet 67P/Churyumov-Gerasimenko: Constraints on its origin
    from OSIRIS observations
Authors: Rickman, H.; Marchi, S.; A'Hearn, M. F.; Barbieri, C.;
   El-Maarry, M. R.; Güttler, C.; Ip, W. -H.; Keller, H. U.; Lamy,
   P.; Marzari, F.; Massironi, M.; Naletto, G.; Pajola, M.; Sierks, H.;
   Koschny, D.; Rodrigo, R.; Barucci, M. A.; Bertaux, J. -L.; Bertini,
   I.; Cremonese, G.; Da Deppo, V.; Debei, S.; De Cecco, M.; Fornasier,
   S.; Fulle, M.; Groussin, O.; Gutiérrez, P. J.; Hviid, S. F.; Jorda,
   L.; Knollenberg, J.; Kramm, J. -R.; Kührt, E.; Küppers, M.; Lara,
   L. M.; Lazzarin, M.; Lopez Moreno, J. J.; Michalik, H.; Sabau, L.;
   Thomas, N.; Vincent, J. -B.; Wenzel, K. -P.
2015A&A...583A..44R    Altcode: 2015arXiv150507021R
  Context. One of the main aims of the ESA Rosetta mission is to study the
  origin of the solar system by exploring comet 67P/Churyumov-Gerasimenko
  at close range. <BR /> Aims: In this paper we discuss the origin and
  evolution of comet 67P/Churyumov-Gerasimenko in relation to that of
  comets in general and in the framework of current solar system formation
  models. <BR /> Methods: We use data from the OSIRIS scientific cameras
  as basic constraints. In particular, we discuss the overall bi-lobate
  shape and the presence of key geological features, such as layers
  and fractures. We also treat the problem of collisional evolution of
  comet nuclei by a particle-in-a-box calculation for an estimate of the
  probability of survival for 67P/Churyumov-Gerasimenko during the early
  epochs of the solar system. <BR /> Results: We argue that the two lobes
  of the 67P/Churyumov-Gerasimenko nucleus are derived from two distinct
  objects that have formed a contact binary via a gentle merger. The
  lobes are separate bodies, though sufficiently similar to have formed
  in the same environment. An estimate of the collisional rate in the
  primordial, trans-planetary disk shows that most comets of similar
  size to 67P/Churyumov-Gerasimenko are likely collisional fragments,
  although survival of primordial planetesimals cannot be excluded. <BR />
  Conclusions: A collisional origin of the contact binary is suggested,
  and the low bulk density of the aggregate and abundance of volatile
  species show that a very gentle merger must have occurred. We thus
  consider two main scenarios: the primordial accretion of planetesimals,
  and the re-accretion of fragments after an energetic impact onto a
  larger parent body. We point to the primordial signatures exhibited
  by 67P/Churyumov-Gerasimenko and other comet nuclei as critical tests
  of the collisional evolution.

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Title: Large-scale dust jets in the coma of 67P/Churyumov-Gerasimenko
    as seen by the OSIRIS instrument onboard Rosetta
Authors: Lara, L. M.; Lowry, S.; Vincent, J. -B.; Gutiérrez, P. J.;
   Rożek, A.; La Forgia, F.; Oklay, N.; Sierks, H.; Barbieri, C.; Lamy,
   P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller, H. U.; Agarwal,
   J.; Auger, A. -T.; A'Hearn, M. F.; Barucci, M. A.; Bertaux, J. -L.;
   Bertini, I.; Besse, S.; Bodewits, D.; Cremonese, G.; Davidsson,
   B.; Da Deppo, V.; Debei, S.; De Cecco, M.; El-Maarry, M. R.; Ferri,
   F.; Fornasier, S.; Fulle, M.; Groussin, O.; Gutiérrez-Marques, P.;
   Güttler, C.; Hviid, S. F.; Ip, W. -H.; Jorda, L.; Knollenberg, J.;
   Kovacs, G.; Kramm, J. -R.; Kührt, E.; Küppers, M.; Lazzarin, M.;
   Lin, Z. -Y.; López-Moreno, J. J.; Magrin, S.; Marzari, F.; Michalik,
   H.; Moissl-Fraund, R.; Moreno, F.; Mottola, S.; Naletto, G.; Pajola,
   M.; Pommerol, A.; Thomas, N.; Sabau, M. D.; Tubiana, C.
2015A&A...583A...9L    Altcode:
  Context. During the most recent perihelion passage in 2009 of comet
  67P/Churyumov-Gerasimenko (67P), ground-based observations showed
  an anisotropic dust coma where jet-like features were detected at ~
  1.3 AU from the Sun. The current perihelion passage is exceptional as
  the Rosetta spacecraft is monitoring the nucleus activity since March
  2014, when a clear dust coma was already surrounding the nucleus at
  4.3 AU from the Sun. Subsequently, the OSIRIS camera also witnessed
  an outburst in activity between April 27 and 30, and since mid-July,
  the dust coma at r<SUB>h</SUB> ~ 3.7-3.6 AU preperihelion is clearly
  non-isotropic, pointing to the existence of dust jet-like features. <BR
  /> Aims: We aim to ascertain on the nucleus surface the origin of the
  dust jet-like features detected as early as in mid-July 2014. This will
  help to establish how the localized comet nucleus activity compares
  with that seen in previous apparitions and will also help following its
  evolution as the comet approaches its perihelion, at which phase most
  of the jets were detected from ground-based observations. Determining
  these areas also allows locating them in regions on the nucleus with
  spectroscopic or geomorphological distinct characteristics. <BR />
  Methods: Three series of dust images of comet 67P obtained with the
  Wide Angle Camera (WAC) of the OSIRIS instrument onboard the Rosetta
  spacecraft were processed with different enhancement techniques. This
  was made to clearly show the existence of jet-like features in the
  dust coma, whose appearance toward the observer changed as a result
  of the rotation of the comet nucleus and of the changing observing
  geometry from the spacecraft. The position angles of these features
  in the coma together with information on the observing geometry,
  nucleus shape, and rotation, allowed us to determine the most likely
  locations on the nucleus surface where the jets originate from. <BR
  /> Results: Geometrical tracing of jet sources indicates that the
  activity of the nucleus of 67P gave rise during July and August 2014
  to large-scale jet-like features from the Hapi, Hathor, Anuket, and
  Aten regions, confirming that active regions may be present on the
  nucleus localized at 60° northern latitude as deduced from previous
  comet apparitions. There are also hints that large-scale jets observed
  from the ground are possibly composed, at their place of origin on
  the nucleus surface, of numerous small-scale features.

---------------------------------------------------------
Title: Search for satellites near comet 67P/Churyumov-Gerasimenko
    using Rosetta/OSIRIS images
Authors: Bertini, I.; Gutiérrez, P. J.; Lara, L. M.; Marzari, F.;
   Moreno, F.; Pajola, M.; La Forgia, F.; Sierks, H.; Barbieri, C.; Lamy,
   P.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller, H. U.; Agarwal,
   J.; A'Hearn, M. F.; Barucci, M. A.; Bertaux, J. -L.; Cremonese, G.;
   Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.; Ferri, F.;
   Fornasier, S.; Fulle, M.; Giacomini, L.; Groussin, O.; Güttler, C.;
   Hviid, S. F.; Ip, W. -H.; Jorda, L.; Knollenberg, J.; Kramm, J. R.;
   Kührt, E.; Küppers, M.; Lazzarin, M.; Lopez Moreno, J. J.; Magrin,
   S.; Massironi, M.; Michalik, H.; Mottola, S.; Naletto, G.; Oklay,
   N.; Thomas, N.; Tubiana, C.; Vincent, J. -B.
2015A&A...583A..19B    Altcode:
  Context. TheEuropean Space Agency Rosetta mission reached and
  started escorting its main target, the Jupiter-family comet
  67P/Churyumov-Gerasimenko, at the beginning of August 2014. Within
  the context of solar system small bodies, satellite searches from
  approaching spacecraft were extensively used in the past to study the
  nature of the visited bodies and their collisional environment. <BR />
  Aims: During the approaching phase to the comet in July 2014, the OSIRIS
  instrument onboard Rosetta performed a campaign aimed at detecting
  objects in the vicinity of the comet nucleus and at measuring these
  objects' possible bound orbits. In addition to the scientific purpose,
  the search also focused on spacecraft security to avoid hazardous
  material in the comet's environment. <BR /> Methods: Images in the
  red spectral domain were acquired with the OSIRIS Narrow Angle Camera,
  when the spacecraft was at a distance between 5785 km and 5463 km to
  the comet, following an observational strategy tailored to maximize the
  scientific outcome. From the acquired images, sources were extracted
  and displayed to search for plausible displacements of all sources from
  image to image. After stars were identified, the remaining sources were
  thoroughly analyzed. To place constraints on the expected displacements
  of a potential satellite, we performed Monte Carlo simulations on the
  apparent motion of potential satellites within the Hill sphere. <BR />
  Results: We found no unambiguous detections of objects larger than ~6
  m within ~20 km and larger than ~1 m between ~20 km and ~110 km from
  the nucleus, using images with an exposure time of 0.14 s and 1.36 s,
  respectively. Our conclusions are consistent with independent works on
  dust grains in the comet coma and on boulders counting on the nucleus
  surface. Moreover, our analysis shows that the comet outburst detected
  at the end of April 2014 was not strong enough to eject large objects
  and to place them into a stable orbit around the nucleus. Our findings
  underline that it is highly unlikely that large objects survive for
  a long time around cometary nuclei.

---------------------------------------------------------
Title: Rotating dust particles in the coma of comet
    67P/Churyumov-Gerasimenko
Authors: Fulle, M.; Ivanovski, S. L.; Bertini, I.; Gutierrez, P.;
   Lara, L.; Sierks, H.; Zakharov, V.; Della Corte, V.; Rotundi, A.;
   Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.;
   Keller, H. U.; Agarwal, J.; A'Hearn, M. F.; Barucci, M. A.; Bertaux,
   J. -L.; Bodewits, D.; Cremonese, G.; Da Deppo, V.; Davidsson, B.;
   Debei, S.; De Cecco, M.; Fornasier, S.; Groussin, O.; Güttler, C.;
   Hviid, S. F.; Ip, W.; Jorda, L.; Knollenberg, J.; Kramm, R.; Kührt,
   E.; Küppers, M.; Lazzarin, M.; Lopez-Moreno, J. J.; Marzari, F.;
   Michalik, H.; Naletto, G.; Oklay, N.; Sabau, L.; Thomas, N.; Tubiana,
   C.; Vincent, J. -B.; Wenzel, K. -P.
2015A&A...583A..14F    Altcode:
  Context. During September and October 2014, the OSIRIS cameras onboard
  the ESA Rosetta mission detected millions of single particles. Many of
  these dust particlesappear as long tracks (due to both the dust proper
  motion and the spacecraft motion during the exposure time) with a clear
  brightness periodicity. <BR /> Aims: We interpret the observed periodic
  features as a rotational and translational motion of aspherical dust
  grains. <BR /> Methods: By counting the peaks of each track, we obtained
  statistics of a rotation frequency. We compared these results with
  the rotational frequency predicted by a model of aspherical dust grain
  dynamics in a model gas flow. By testing many possible sets of physical
  conditions and grain characteristics, we constrained the rotational
  properties of dust grains. <BR /> Results: We analyzed on the motion
  of rotating aspherical dust grains with different cross sections in
  flow conditions corresponding to the coma of 67P/Churyumov-Gerasimenko
  qualitatively and quantitatively. Based on the OSIRIS observations,
  we constrain the possible physical parameters of the grains.

---------------------------------------------------------
Title: Activity and jets of comet 67P, as observed by OSIRIS since
    August 2014
Authors: Vincent, Jean-Baptiste; Oklay, Nilda; Pajola, Maurizio;
   Höfner, Sebastian; Sierks, Holger; Barbieri, Cesare; Lamy, Philippe;
   Rodrigo, Rafael; Rickman, Hans; Koschny, Detlef
2015DPS....4741307V    Altcode:
  Dust jets, i.e. fuzzy collimated streams of cometary material arising
  from the nucleus, have been observed in-situ on all comets since the
  Giotto mission flew by comet 1P/Halley in 1986. Yet their formation
  mechanism remains unknown. Several solutions have been proposed, from
  localized physical mechanisms on the surface/sub-surface to purely
  dynamical processes involving the focusing of gas flows by the local
  topography. While the latter seems to be responsible forthe larger
  features, high resolution imagery has shown that broad streams are
  composed of many smaller features (a few meters wide) that connect
  directly to the nucleus surface.The OSIRIS cameras on board Rosetta are
  monitoring these jets in high resolution images since August 2014. We
  followed this type of activity from 3.6 AU to perihelion (1.23 AU). We
  have traced the jets back to their sources on the surface and noticed
  a good correlation with sub-solar latitude, surface morphologies, and
  color variations. As the comet receives more insolation, we observed
  different type of jets, some of them sustained beyond the local sunset,
  and an increasing number of transient events with sudden release of gas
  and dust.We will present here how activity changes with local seasons
  and how it contributes to the erosion of the surface.Acknowledgements:
  OSIRIS was built by a consortium led by the Max-Planck-Institut für
  Sonnensystemforschung, Göttingen, Germany, in collaboration with
  CISAS, University of Padova, Italy, the Laboratoire d'Astrophysique de
  Marseille, France, the Instituto de Astrofi­sica de Andalucia, CSIC,
  Granada, Spain, the Scientific Support Office of the European Space
  Agency, Noordwijk, The Netherlands, the Instituto Nacional de Tecnica
  Aeroespacial, Madrid, Spain, the Universidad Politechnica de Madrid,
  Spain, the Department of Physics and Astronomy of Uppsala University,
  Sweden, and the Institut für Datentechnik und Kommunikationsnetze der
  Technischen Universität Braunschweig, Germany. We thank the Rosetta
  Science Ground Segment at ESAC, the Rosetta Mission Operations Centre
  at ESOC and the Rosetta Project at ESTEC for their outstanding work
  enabling the science return of the Rosetta Mission.

---------------------------------------------------------
Title: Temporal morphological changes in the Imhotep region of comet
    67P/Churyumov-Gerasimenko
Authors: Groussin, O.; Sierks, H.; Barbieri, C.; Lamy, P.; Rodrigo,
   R.; Koschny, D.; Rickman, H.; Keller, H. U.; A'Hearn, M. F.; Auger,
   A. -T.; Barucci, M. A.; Bertaux, J. -L.; Bertini, I.; Besse, S.;
   Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco,
   M.; El-Maarry, M. R.; Fornasier, S.; Fulle, M.; Gutiérrez, P. J.;
   Güttler, C.; Hviid, S.; Ip, W. -H.; Jorda, L.; Knollenberg, J.;
   Kovacs, G.; Kramm, J. R.; Kührt, E.; Küppers, M.; Lara, L. M.;
   Lazzarin, M.; Lopez Moreno, J. J.; Lowry, S.; Marchi, S.; Marzari,
   F.; Massironi, M.; Mottola, S.; Naletto, G.; Oklay, N.; Pajola, M.;
   Pommerol, A.; Thomas, N.; Toth, I.; Tubiana, C.; Vincent, J. -B.
2015A&A...583A..36G    Altcode: 2015arXiv150902794G
  <BR /> Aims: We report on the first major temporal morphological
  changes observed on the surface of the nucleus of comet
  67P/Churyumov-Gerasimenko in the smooth terrains of the Imhotep
  region. <BR /> Methods: We used images of the OSIRIS cameras onboard
  Rosetta to follow the temporal changes from 24 May 2015 to 11 July
  2015. <BR /> Results: The morphological changes observed on the
  surface are visible in the form of roundish features that are growing
  in size from a given location in a preferential direction at a rate of
  5.6-8.1 × 10<SUP>-5</SUP> m s<SUP>-1</SUP> during the observational
  period. The location where the changes started and the contours of the
  expanding features are bluer than the surroundings, which suggests
  that ices (H<SUB>2</SUB>O and/or CO<SUB>2</SUB>) are exposed on the
  surface. However, sublimation of ices alone is not sufficient to explain
  the observed expanding features. No significant variations in the dust
  activity pattern are observed during the period of changes.

---------------------------------------------------------
Title: GIADA: shining a light on the monitoring of the comet dust
    production from the nucleus of 67P/Churyumov-Gerasimenko
Authors: Della Corte, V.; Rotundi, A.; Fulle, M.; Gruen, E.;
   Weissman, P.; Sordini, R.; Ferrari, M.; Ivanovski, S.; Lucarelli,
   F.; Accolla, M.; Zakharov, V.; Mazzotta Epifani, E.; Lopez-Moreno,
   J. J.; Rodriguez, J.; Colangeli, L.; Palumbo, P.; Bussoletti, E.;
   Crifo, J. F.; Esposito, F.; Green, S. F.; Lamy, P. L.; McDonnell,
   J. A. M.; Mennella, V.; Molina, A.; Morales, R.; Moreno, F.; Ortiz,
   J. L.; Palomba, E.; Perrin, J. M.; Rietmeijer, F. J. M.; Rodrigo, R.;
   Zarnecki, J. C.; Cosi, M.; Giovane, F.; Gustafson, B.; Herranz, M. L.;
   Jeronimo, J. M.; Leese, M. R.; Lopez-Jimenez, A. C.; Altobelli, N.
2015A&A...583A..13D    Altcode:
  Context. During the period between 15 September 2014 and 4 February
  2015, the Rosetta spacecraft accomplished the circular orbit phase
  around the nucleus of comet 67P/Churyumov-Gerasimenko (67P). The Grain
  Impact Analyzer and Dust Accumulator (GIADA) onboard Rosetta monitored
  the 67P coma dust environment for the entire period. <BR /> Aims: We
  aim to describe the dust spatial distribution in the coma of comet 67P
  by means of in situ measurements. We determine dynamical and physical
  properties of cometary dust particles to support the study of the
  production process and dust environment modification. <BR /> Methods:
  We analyzed GIADA data with respect to the observation geometry and
  heliocentric distance to describe the coma dust spatial distribution
  of 67P, to monitor its activity, and to retrieve information on active
  areas present on its nucleus. We combined GIADA detection information
  with calibration activity to distinguish different types of particles
  that populate the coma of 67P: compact particles and fluffy porous
  aggregates. By means of particle dynamical parameters measured by
  GIADA, we studied the dust acceleration region. <BR /> Results: GIADA
  was able to distinguish different types of particles populating the
  coma of 67P: compact particles and fluffy porous aggregates. Most of
  the compact particle detections occurred at latitudes and longitudes
  where the spacecraft was in view of the comet's neck region of the
  nucleus, the so-called Hapi region. This resulted in an oscillation
  of the compact particle abundance with respect to the spacecraft
  position and a global increase as the comet moved from 3.36 to 2.43
  AU heliocentric distance. The speed of these particles, having masses
  from 10<SUP>-10</SUP> to 10<SUP>-7</SUP> kg, ranged from 0.3 to 12.2 m
  s<SUP>-1</SUP>. The variation of particle mass and speed distribution
  with respect to the distance from the nucleus gave indications of the
  dust acceleration region. The influence of solar radiation pressure on
  micron and submicron particles was studied. The integrated dust mass
  flux collected from the Sun direction, that is, particles reflected by
  solar radiation pressure, was three times higher than the flux coming
  directly from the comet nucleus. The awakening 67P comet shows a strong
  dust flux anisotropy, confirming what was suggested by on-ground dust
  coma observations performed in 2008.

---------------------------------------------------------
Title: Scientific assessment of the quality of OSIRIS images
Authors: Tubiana, C.; Güttler, C.; Kovacs, G.; Bertini, I.; Bodewits,
   D.; Fornasier, S.; Lara, L.; La Forgia, F.; Magrin, S.; Pajola, M.;
   Sierks, H.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.;
   Rickman, H.; Keller, H. U.; Agarwal, J.; A'Hearn, M. F.; Barucci,
   M. A.; Bertaux, J. -L.; Besse, S.; Boudreault, S.; Cremonese, G.;
   Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.; El-Maarry,
   M. R.; Fulle, M.; Groussin, O.; Gutiérrez-Marques, P.; Gutiérrez,
   P. J.; Hoekzema, N.; Hofmann, M.; Hviid, S. F.; Ip, W. -H.; Jorda, L.;
   Knollenberg, J.; Kramm, J. -R.; Kührt, E.; Küppers, M.; Lazzarin,
   M.; Lopez Moreno, J. J.; Marzari, F.; Massironi, M.; Michalik, H.;
   Moissl, R.; Naletto, G.; Oklay, N.; Scholten, F.; Shi, X.; Thomas,
   N.; Vincent, J. -B.
2015A&A...583A..46T    Altcode:
  Context. OSIRIS, the scientific imaging system onboard the
  ESA Rosetta spacecraft, has been imaging the nucleus of comet
  67P/Churyumov-Gerasimenko and its dust and gas environment since March
  2014. The images serve different scientific goals, from morphology
  and composition studies of the nucleus surface, to the motion and
  trajectories of dust grains, the general structure of the dust coma,
  the morphology and intensity of jets, gas distribution, mass loss, and
  dust and gas production rates. <BR /> Aims: We present the calibration
  of the raw images taken by OSIRIS and address the accuracy that we
  can expect in our scientific results based on the accuracy of the
  calibration steps that we have performed. <BR /> Methods: We describe
  the pipeline that has been developed to automatically calibrate the
  OSIRIS images. Through a series of steps, radiometrically calibrated and
  distortion corrected images are produced and can be used for scientific
  studies. Calibration campaigns were run on the ground before launch
  and throughout the years in flight to determine the parameters that
  are used to calibrate the images and to verify their evolution with
  time. We describe how these parameters were determined and we address
  their accuracy. <BR /> Results: We provide a guideline to the level of
  trust that can be put into the various studies performed with OSIRIS
  images, based on the accuracy of the image calibration.

---------------------------------------------------------
Title: Photometric properties of the nucleus of
    67P/Churyumov-Gerasimenko from OSIRIS/Rosetta, space telescope,
    and ground-based observations
Authors: Lamy, Philippe L.; Faury, Guillaume; Toth, Imre; Jorda,
   Laurent; Gaskell, Robert; Groussin, Olivier; Capanna, Claire
2015DPS....4741303L    Altcode:
  In-situ imaging of the nucleus of comet 67P/Churyumov-Gerasimenko by the
  OSIRIS Narrow Angle Camera (NAC) allows an in depth characterization of
  its photometric properties that can be compared with remote observations
  thus helping in the interpretation of other nuclei. We performed
  a photometric analysis of both unresolved and resolved NAC images
  of the nucleus obtained during twenty five observational campaigns
  spreading from 23 March to 6 August 2014 with up to twelve filters whose
  spectral coverage extended from 271 to 986 nm. An accurate photometric
  calibration was obtained from the observations of a solar analog star,
  16 Cyg B. We further combined this analysis with previous observations
  obtained with the Hubble and Spitzer space telescopes and ground-based
  telescopes. The analysis further incorporates the shape model and the
  rotational state the nucleus of \67P independently determined from the
  NAC images. We will present results on the geometric albedo, phase
  function, color and thermal properties and put them in the broader
  context of properties of cometary nuclei.

---------------------------------------------------------
Title: Gravitational slopes, geomorphology, and material strengths
    of the nucleus of comet 67P/Churyumov-Gerasimenko from OSIRIS
    observations
Authors: Groussin, O.; Jorda, L.; Auger, A. -T.; Kührt, E.; Gaskell,
   R.; Capanna, C.; Scholten, F.; Preusker, F.; Lamy, P.; Hviid, S.;
   Knollenberg, J.; Keller, U.; Huettig, C.; Sierks, H.; Barbieri,
   C.; Rodrigo, R.; Koschny, D.; Rickman, H.; A'Hearn, M. F.; Agarwal,
   J.; Barucci, M. A.; Bertaux, J. -L.; Bertini, I.; Boudreault, S.;
   Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco,
   M.; El-Maarry, M. R.; Fornasier, S.; Fulle, M.; Gutiérrez, P. J.;
   Güttler, C.; Ip, W. -H.; Kramm, J. -R.; Küppers, M.; Lazzarin, M.;
   Lara, L. M.; Lopez Moreno, J. J.; Marchi, S.; Marzari, F.; Massironi,
   M.; Michalik, H.; Naletto, G.; Oklay, N.; Pommerol, A.; Pajola, M.;
   Thomas, N.; Toth, I.; Tubiana, C.; Vincent, J. -B.
2015A&A...583A..32G    Altcode: 2015arXiv150902707G
  <BR /> Aims: We study the link between gravitational slopes and the
  surface morphology on the nucleus of comet 67P/Churyumov-Gerasimenko
  and provide constraints on the mechanical properties of the cometary
  material (tensile, shear, and compressive strengths). <BR /> Methods:
  We computed the gravitational slopes for five regions on the nucleus
  that are representative of the different morphologies observed on the
  surface (Imhotep, Ash, Seth, Hathor, and Agilkia), using two shape
  models computed from OSIRIS images by the stereo-photoclinometry (SPC)
  and stereo-photogrammetry (SPG) techniques. We estimated the tensile,
  shear, and compressive strengths using different surface morphologies
  (overhangs, collapsed structures, boulders, cliffs, and Philae's
  footprint) and mechanical considerations. <BR /> Results: The different
  regions show a similar general pattern in terms of the relation between
  gravitational slopes and terrain morphology: i) low-slope terrains
  (0-20°) are covered by a fine material and contain a few large (&gt;10
  m) and isolated boulders; ii) intermediate-slope terrains (20-45°) are
  mainly fallen consolidated materials and debris fields, with numerous
  intermediate-size boulders from &lt;1 m to 10 m for the majority of
  them; and iii) high-slope terrains (45-90°) are cliffs that expose a
  consolidated material and do not show boulders or fine materials. The
  best range for the tensile strength of overhangs is 3-15 Pa (upper limit
  of 150 Pa), 4-30 Pa for the shear strength of fine surface materials and
  boulders, and 30-150 Pa for the compressive strength of overhangs (upper
  limit of 1500 Pa). The strength-to-gravity ratio is similar for 67P
  and weak rocks on Earth. As a result of the low compressive strength,
  the interior of the nucleus may have been compressed sufficiently to
  initiate diagenesis, which could have contributed to the formation of
  layers. Our value for the tensile strength is comparable to that of
  dust aggregates formed by gravitational instability and tends to favor
  a formation of comets by the accrection of pebbles at low velocities.

---------------------------------------------------------
Title: OSIRIS observations of meter-sized exposures of H<SUB>2</SUB>O
    ice at the surface of 67P/Churyumov-Gerasimenko and interpretation
    using laboratory experiments
Authors: Pommerol, A.; Thomas, N.; El-Maarry, M. R.; Pajola, M.;
   Groussin, O.; Auger, A. -T.; Oklay, N.; Fornasier, S.; Feller, C.;
   Davidsson, B.; Gracia-Berná, A.; Jost, B.; Marschall, R.; Poch,
   O.; Barucci, M. A.; Bertaux, J. -L.; La Forgia, F.; Keller, H. U.;
   Kührt, E.; Lowry, S. C.; Mottola, S.; Naletto, G.; Sierks, H.;
   Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.;
   Agarwal, J.; A'Hearn, M. F.; Bertini, I.; Boudreault, S.; Cremonese,
   G.; Da Deppo, V.; De Cecco, M.; Debei, S.; Güttler, C.; Fulle, M.;
   Gutierrez, P. J.; Hviid, S. F.; Ip, W. -H.; Jorda, L.; Knollenberg,
   J.; Kovacs, G.; Kramm, J. -R.; Küppers, E.; Lara, L.; Lazzarin,
   M.; Lopez Moreno, J. L.; Marzari, F.; Michalik, H.; Preusker, F.;
   Scholten, F.; Tubiana, C.; Vincent, J. -B.
2015A&A...583A..25P    Altcode:
  Since OSIRIS started acquiring high-resolution observations of the
  surface of the nucleus of comet 67P/Churyumov-Gerasimenko, over one
  hundred meter-sized bright spots have been identified in numerous types
  of geomorphologic regions, but mostly located in areas receiving low
  insolation. The bright spots are either clustered, in debris fields
  close to decameter-high cliffs, or isolated without structural relation
  to the surrounding terrain. They can be up to ten times brighter than
  the average surface of the comet at visible wavelengths and display a
  significantly bluer spectrum. They do not exhibit significant changes
  over a period of a few weeks. All these observations are consistent
  with exposure of water ice at the surface of boulders produced by
  dislocation of the weakly consolidated layers that cover large areas
  of the nucleus. Laboratory experiments show that under simulated comet
  surface conditions, analog samples acquire a vertical stratification
  with an uppermost porous mantle of refractory dust overlaying a layer
  of hard ice formed by recondensation or sintering under the insulating
  dust mantle. The evolution of the visible spectrophotometric properties
  of samples during sublimation is consistent with the contrasts of
  brightness and color seen at the surface of the nucleus. Clustered
  bright spots are formed by the collapse of overhangs that is triggered
  by mass wasting of deeper layers. Isolated spots might be the result
  of the emission of boulders at low velocity that are redepositioned
  in other regions.

---------------------------------------------------------
Title: Spectrophotometric properties of the nucleus of comet
    67P/Churyumov-Gerasimenko from the OSIRIS instrument onboard the
    ROSETTA spacecraft
Authors: Fornasier, S.; Hasselmann, P. H.; Barucci, M. A.; Feller,
   C.; Besse, S.; Leyrat, C.; Lara, L.; Gutierrez, P. J.; Oklay, N.;
   Tubiana, C.; Scholten, F.; Sierks, H.; Barbieri, C.; Lamy, P. L.;
   Rodrigo, R.; Koschny, D.; Rickman, H.; Keller, H. U.; Agarwal, J.;
   A'Hearn, M. F.; Bertaux, J. -L.; Bertini, I.; Cremonese, G.; Da Deppo,
   V.; Davidsson, B.; Debei, S.; De Cecco, M.; Fulle, M.; Groussin, O.;
   Güttler, C.; Hviid, S. F.; Ip, W.; Jorda, L.; Knollenberg, J.; Kovacs,
   G.; Kramm, R.; Kührt, E.; Küppers, M.; La Forgia, F.; Lazzarin, M.;
   Lopez Moreno, J. J.; Marzari, F.; Matz, K. -D.; Michalik, H.; Moreno,
   F.; Mottola, S.; Naletto, G.; Pajola, M.; Pommerol, A.; Preusker,
   F.; Shi, X.; Snodgrass, C.; Thomas, N.; Vincent, J. -B.
2015A&A...583A..30F    Altcode: 2015arXiv150506888F
  Context. The Rosetta mission of the European Space Agency has been
  orbiting the comet 67P/Churyumov-Gerasimenko (67P) since August 2014
  and is now in its escort phase. A large complement of scientific
  experiments designed to complete the most detailed study of a comet
  ever attempted are onboard Rosetta. <BR /> Aims: We present results for
  the photometric and spectrophotometric properties of the nucleus of
  67P derived from the OSIRIS imaging system, which consists of a Wide
  Angle Camera (WAC) and a Narrow Angle Camera (NAC). The observations
  presented here were performed during July and the beginning of
  August 2014, during the approach phase, when OSIRIS was mapping the
  surface of the comet with several filters at different phase angles
  (1.3°-54°). The resolution reached up to 2.1 m/px. <BR /> Methods:
  The OSIRIS images were processed with the OSIRIS standard pipeline,
  then converted into I/F radiance factors and corrected for the
  illumination conditions at each pixel using the Lommel-Seeliger disk
  law. Color cubes of the surface were produced by stacking registered and
  illumination-corrected images. Furthermore, photometric analysis was
  performed both on disk-averaged photometry in several filters and on
  disk-resolved images acquired with the NAC orange filter, centered at
  649 nm, using Hapke modeling. <BR /> Results: The disk-averaged phase
  function of the nucleus of 67P shows a strong opposition surge with
  a G parameter value of -0.13 ± 0.01 in the HG system formalism and
  an absolute magnitude H<SUB>v</SUB>(1,1,0) = 15.74 ± 0.02 mag. The
  integrated spectrophotometry in 20 filters covering the 250-1000 nm
  wavelength range shows a red spectral behavior, without clear absorption
  bands except for a potential absorption centered at ~290 nm that is
  possibly due to SO<SUB>2</SUB> ice. The nucleus shows strong phase
  reddening, with disk-averaged spectral slopes increasing from 11%/(100
  nm) to 16%/(100 nm) in the 1.3°-54° phase angle range. The geometric
  albedo of the comet is 6.5 ± 0.2% at 649 nm, with local variations of
  up to ~16% in the Hapi region. From the disk-resolved images we computed
  the spectral slope together with local spectrophotometry and identified
  three distinct groups of regions (blue, moderately red, and red). The
  Hapi region is the brightest, the bluest in term of spectral slope,
  and the most active surface on the comet. Local spectrophotometry shows
  an enhancement of the flux in the 700-750 nm that is associated with
  coma emissions. <P />Table 1 is available in electronic form at <A
  href="http://www.aanda.org/10.1051/0004-6361/201525901/olm">http://www.aanda.org</A>

---------------------------------------------------------
Title: 3D reconstruction of the final PHILAE landing site: Abydos
Authors: Capanna, Claire; Jorda, Laurent; Lamy, Philippe; Gesquière,
   Gilles; Delmas, Cédric; Durand, Joëlle; Gaudon, Philippe; Jurado,
   Eric
2015DPS....4741311C    Altcode:
  The Abydos region is the region of the final landing site of the PHILAE
  lander. The landing site has been potentially identified on images of
  this region acquired by the OSIRIS imaging system aboard the orbiter
  before (Oct 22, 2014) and after (Dec 6-13, 2014) the landing of PHILAE
  (Lamy et al., in prep.). Assuming that this identification is correct,
  we reconstructed the topography of Abydos in 3D using a method called
  “multiresolution photoclinometry by deformation” (MPCD, Capanna et
  al., The Visual Computer, 29(6-8): 825-835, 2013). The method works
  in two steps: (a) a DTM of this region is extracted from the global
  MPCD shape model, (b) the resulting triangular mesh is progressively
  deformed at increasing spatial resolution in order to match a set
  of 14 images of Abydos at pixel resolutions between 1 and 8 m. The
  method used to perform the image matching is the L-BFGS-b non-linear
  optimization (Morales et al., ACM Trans. Math. Softw., 38(1): 1-4,
  2011).In spite of the very unfavourable illumination conditions, we
  achieve a vertical accuracy of about 3 m, while the horizontal sampling
  is 0.5 m. The accuracy is limited by high incidence angles on the images
  (about 60 deg on average) combined with a complex topography including
  numerous cliffs and a few overhangs. We also check the compatibility of
  the local DTM with the images obtained by the CIVA-P instrument aboard
  PHILAE. If the Lamy et al. identification is correct, our DTM shows that
  PHILAE landed in a cavity at the bottom of a small cliff of 8 m height.

---------------------------------------------------------
Title: The nucleus of comet 67P through the eyes of the OSIRIS cameras
Authors: Guettler, Carsten; Sierks, Holger; Barbieri, Cesare; Lamy,
   Philippe; Rodrigo, Rafael; Koschny, Detlef; Rickman, Hans; OSIRIS Team;
   Capaccioni, Fabrizio; Filacchione, Gianrico; Ciarniello, Mauro; Erard,
   Stephane; Rinaldi, Giovanna; Tosi, Federico
2015DPS....4741301G    Altcode:
  The Rosetta spacecraft is studying comet 67P/Churyumov-Gerasimenko
  from a close distance since August 2014. Onboard the spacecraft, the
  two scientific cameras, the OSIRIS narrow- and the wide-angle camera,
  are observing the cometary nucleus, its activity, as well as the dust
  and gas environment.This overview paper will cover OSIRIS science from
  the early arrival and mapping phase, the PHILAE landing, and the escort
  phase including the two close fly-bys. With a first characterization
  of global physical parameters of the nucleus, the OSIRIS cameras also
  provided the data to reconstruct a 3D shape model of the comet and a
  division into morphologic sub-units. From observations of near-surface
  activity, jet-like features can be projected onto the surface and active
  sources can be correlated with surface features like cliffs, pits,
  or flat planes. The increase of activity during and after perihelion
  in August 2015 showed several outbursts, which were seen as strong,
  collimated jets originating from the southern hemisphere.A comparison
  of results between different Rosetta instruments will give further
  inside into the physics of the comet's nucleus and its coma. The OSIRIS
  and VIRTIS instruments are particularly well suited to support and
  complement each other. With an overlap in spectral range, one instrument
  can provide the best spatial resolution while the other is strong in the
  spectral resolution. A summary on collaborative efforts will be given.

---------------------------------------------------------
Title: Characterization of OSIRIS NAC filters for the interpretation
    of multispectral data of comet 67P/Churyumov-Gerasimenko
Authors: Oklay, N.; Vincent, J. -B.; Sierks, H.; Besse, S.; Pajola, M.;
   Bertini, I.; Rickman, H.; La Forgia, F.; Barucci, A. M.; Fornasier,
   S.; Barbieri, C.; Koschny, D.; Lamy, P. L.; Rodrigo, R.; Agarwal,
   J.; A'Hearn, M. F.; Bertaux, J. -L.; Cremonese, G.; Da Deppo, V.;
   Davidsson, B.; Debei, S.; De Cecco, M.; Fulle, M.; Groussin, O.;
   Gutiérrez, P. J.; Güttler, C.; Hviid, S. F.; Ip, W. -H.; Jorda, L.;
   Keller, H. U.; Knollenberg, J.; Kramm, J. -R.; Kührt, E.; Küppers,
   M.; Lara, L. M.; Lazzarin, M.; Lopez-Moreno, J. J.; Marzari, F.;
   Michalik, H.; Naletto, G.; Thomas, N.; Tubiana, C.
2015A&A...583A..45O    Altcode:
  Context. We interpret multicolor data from OSIRISNAC for the
  remote-sensing exploration of comet 67P/Churyumov-Gerasimenko. <BR />
  Aims: We determine the most meaningful definition of color maps for
  the characterization of surface variegation with filters available on
  OSIRIS NAC. <BR /> Methods: We analyzed laboratory spectra of selected
  minerals and olivine-pyroxene mixtures seen through OSIRIS NAC filters,
  with spectral methods existing in the literature: reflectance ratios,
  minimum band wavelength, spectral slopes, band tilt, band curvature,
  and visible tilt. <BR /> Results: We emphasize the importance of
  reflectance ratios and particularly the relation of visible tilt
  vs. band tilt. This technique provides a reliable diagnostic of the
  presence of silicates. Color maps constructed by red-green-blue colors
  defined with the green, orange, red, IR, and Fe<SUB>2</SUB>O<SUB>3</SUB>
  filters let us define regions that may significantly differ in
  composition. <P />Appendices are available in electronic form at <A
  href="http://www.aanda.org/10.1051/0004-6361/201525994/olm">http://www.aanda.org</A>

---------------------------------------------------------
Title: The use of 3D shape models of Rosetta targets for morphological
    studies
Authors: Capanna, C.; Jorda, L.; Auger, A. -T.; Groussin, O.; Gaskell,
   R.; Hviid, S.; Lamy, P.
2015EPSC...10..180C    Altcode:
  New 3D reconstruction techniques have been developed during the
  last decade to retrieve the global and/or local topography of small
  solar system bodies from visible images. These techniques can be
  separated into two categories: the so-called "photoclinometric"
  and the so-called "photogrammetric" techniques. Two implementations
  of the photoclinometric technique are available: the SPC technique
  (StereoPhotoClinometry) which combines sparse stereo with a classical
  clinometry algorithm[1] and a more recent method called MSPCD (Multi-
  Resolution Stereo-PhotoClinometry by Deformation) which proceeds
  by iterative deformation of a triangular mesh in a multi-resolution
  scheme[2], using stereo points as a guide during the deformation[3]. Our
  study is based on the 3D shape models of the asteroid Lutetia and of
  the comet 67P/Churyumov- Gerasimenko retrieved by the SPC and MSPCD
  methods. More specifically, we describe how the models produced by
  these two techniques can contribute to detailed and quantitative
  studies of the morphological properties of small bodies through three
  test cases shortly described below.• Measurement of crater depth
  and depth-to-diameter distribution. We show that the reconstruction
  techniques can lead to systematic differences in the measurement
  of crater depth. This will be illustrated by a set of craters[4]
  identified in the Achaia region at the surface of the asteroid
  21 Lutetia. • Calculation of the volume of large boulders at the
  surface of comet 67P/C-G. We show how the reconstruction technique
  affects significantly the volume determination of a large boulder
  named Cheops in the Imhotep region. • Measurement of gravitational
  slopes. We discuss the differences between the gravitational slope
  distributions in Seth obtained with the SPC and MSPCD models[5]. Since
  no ground control points are available on small bodies, we use the
  comparison of high-resolution images with the corresponding synthetic
  images generated with the models[6] to assess their ability to retrieve
  detailed topographic features at the surface of 67P/C-G and Lutetia.

---------------------------------------------------------
Title: Two independent and primitive envelopes of the bilobate
    nucleus of comet 67P
Authors: Massironi, Matteo; Simioni, Emanuele; Marzari, Francesco;
   Cremonese, Gabriele; Giacomini, Lorenza; Pajola, Maurizio; Jorda,
   Laurent; Naletto, Giampiero; Lowry, Stephen; El-Maarry, Mohamed Ramy;
   Preusker, Frank; Scholten, Frank; Sierks, Holger; Barbieri, Cesare;
   Lamy, Philippe; Rodrigo, Rafael; Koschny, Detlef; Rickman, Hans;
   Keller, Horst Uwe; A'Hearn, Michael F.; Agarwal, Jessica; Auger,
   Anne-Thérèse; Barucci, M. Antonella; Bertaux, Jean-Loup; Bertini,
   Ivano; Besse, Sebastien; Bodewits, Dennis; Capanna, Claire; da Deppo,
   Vania; Davidsson, Björn; Debei, Stefano; de Cecco, Mariolino; Ferri,
   Francesca; Fornasier, Sonia; Fulle, Marco; Gaskell, Robert; Groussin,
   Olivier; Gutiérrez, Pedro J.; Güttler, Carsten; Hviid, Stubbe F.; Ip,
   Wing-Huen; Knollenberg, Jörg; Kovacs, Gabor; Kramm, Rainer; Kührt,
   Ekkehard; Küppers, Michael; La Forgia, Fiorangela; Lara, Luisa M.;
   Lazzarin, Monica; Lin, Zhong-Yi; Lopez Moreno, Josè J.; Magrin, Sara;
   Michalik, Harald; Mottola, Stefano; Oklay, Nilda; Pommerol, Antoine;
   Thomas, Nicolas; Tubiana, Cecilia; Vincent, Jean-Baptiste
2015Natur.526..402M    Altcode:
  The factors shaping cometary nuclei are still largely unknown, but
  could be the result of concurrent effects of evolutionary and primordial
  processes. The peculiar bilobed shape of comet 67P/Churyumov-Gerasimenko
  may be the result of the fusion of two objects that were once separate
  or the result of a localized excavation by outgassing at the interface
  between the two lobes. Here we report that the comet's major lobe is
  enveloped by a nearly continuous set of strata, up to 650 metres thick,
  which are independent of an analogous stratified envelope on the minor
  lobe. Gravity vectors computed for the two lobes separately are closer
  to perpendicular to the strata than those calculated for the entire
  nucleus and adjacent to the neck separating the two lobes. Therefore
  comet 67P/Churyumov-Gerasimenko is an accreted body of two distinct
  objects with `onion-like' stratification, which formed before they
  merged. We conclude that gentle, low-velocity collisions occurred
  between two fully formed kilometre-sized cometesimals in the early
  stages of the Solar System. The notable structural similarities between
  the two lobes of comet 67P/Churyumov-Gerasimenko indicate that the
  early-forming cometesimals experienced similar primordial stratified
  accretion, even though they formed independently.

---------------------------------------------------------
Title: Identification and Characterization of the landing site of
    Philae from OSIRIS-NAC Images
Authors: Lamy, P.; Faury, G.; Jorda, L.; Romeuf, D.; Gaskell, R.;
   Jurado, E.; Garmier, R.; Llebaria, A.; Auger, A. -T.; Capanna, C.
2015EPSC...10..783L    Altcode:
  On 12 November 2014, Philae rebounded from its first touchdown
  at the selected Agilka "J" site on the nucleus of Comet
  67P/Churyumov-Gerasimenko, an event captured by the Rosetta's OSIRIS
  narrowangle camera (NAC [1]). Following two additional bounces,
  Philae finally landed at the "K" site later named Abydos. Finding its
  exact location has been a major challenge and could only be indirectly
  constrained. Thanks to CONSERT measurements, it was finally possible to
  bound it by an ellipse of approximately 16 x 160 meters. Complementary
  analyses were performed at CNES-SONC allowing narrowing down the
  location of Philae to an area of approximately 10 m radius based on
  illumination conditions and times of contact between Orbiter and Lander
  during operations. A more precise localization is however hampered by
  the uncertainties affecting the present 3-dimensional reconstruction
  (DTM) of the area, presently at the limit of the illuminated part of
  the nucleus (Figure 1). Spotting Philae on the images of the nucleus
  has been even more challenging. The highest resolution images of
  the region of interest after Philae's landing were obtained by the
  OSIRIS-NAC in mid-December 2014 at a distance of approximately 20 km,
  the image scale implying that Philae would at best appear as a few
  bright pixels. Bright "spots" are however ubiquitous on the surface of
  the nucleus, from glittering rocks or from local icy patches [2]. After
  meticulously scanning the region of interest, several candidates were
  spotted but the ambiguity could only be removed when a pre-landing
  image of the OSIRIS- NAC collection was identified whose geometric
  conditions (illumination and viewing) were very similar to one of the
  post-landing images of 12 December 2014. Although taken at different
  spatial resolutions, all topographic details match, except for one
  bright spot present on the post-landing image as shown in Figure 2. A
  false detection or an artefact have been ruled out as this candidate
  was successfully identified on other images taken in mid-December
  (Figure 2). A local change in the surface is highly unlikely as no
  activity has been detected on this presently poorly illuminated part
  of the nucleus. The determined location is remarkably close to that
  resulting from the indirect constraints, within approximately 10 m,
  a further validation of the probable detection of Philae. In fact,
  this solution satisfies all known constraints, taking into account
  the present uncertainties affecting the DTM. The Abydos area appears
  extremely rough with numerous rocks and boulders scattered around,
  possibly resulting from the local degradation of the rim of the
  Hatmehit depression. The roughness is confirmed by the large values
  of the local slopes determined on the present DTM although they are
  probably underestimated. It is further dramatically illustrated by
  several anaglyphs constructed from all suitable NAC images of the
  landing area, thus allowing a stereo view of the local relief.

---------------------------------------------------------
Title: The low strength of 67P: evidence for a primordial nucleus?
Authors: Groussin, O.; Jorda, L.; Auger, A. -T.; Kührt, E.; Gaskell,
   R.; Capanna, C.; Scholten, F.; Preusker, F.; Lamy, P.; Hviid, S.;
   Knollenberg, J.; Keller, U.; Huettig, C.; Romeuf, D.; Sierks, H.;
   Osiris Team
2015EPSC...10...39G    Altcode:
  Rosetta is orbiting comet 67P/Churyumov- Gerasimenko since August
  2014. The OSIRIS camera [1] onboard this spacecraft has acquired
  hundreds of images of the nucleus surface, with a spatial resolution
  down to the decimeter scale [2]. The images reveal a complex nucleus
  surface made of smooth and hummocky terrains, covered partially or
  entirely by dust or exposing a consolidated material, pits, cliffs and
  fractures from the hundred meter scale to the decimeter scale [3]. The
  nature and origin of these terrains and geomorphological features are
  far from being understood but remain of paramount importance to better
  constrain the formation and evolution scenario of the nucleus of 67P and
  comets in general. This study focuses on the link between the nucleus
  gravitational slopes and surface morphology, to provide constraints
  on the nature of the cometary material and its mechanical properties
  in particular (tensile strength, shear strength and compressive
  strength). The derived strengths can also be used to constrain the
  origin of the nucleus of 67P. We derive a low tensile strength for
  the nucleus, typically from a few tens to a few hundreds Pa [4]. Our
  results tend to favour a formation of comets by pebble accretion in a
  region of higher concentration of particles like a vortice [5, 6, 7],
  which implies a gentle formation process by accretion at low velocity on
  the order of 1ms-1 or less. On the contrary, the hierarchical accretion
  model with velocities up to 50ms-1 for particles larger than 1m [8],
  or the collisional scenario between two large bodies of tens of km
  or more with an internal compression by gravity larger than 10 kPa
  [9], although not excluded, are less favored. This points towards a
  primordial nucleus, which might have not been strongly affected by
  collisions since its formation.

---------------------------------------------------------
Title: Meter-scale polygons on 67P/Churyumov-Gerasimenko as evidences
    of near subsurface water ice
Authors: Auger, A. -T.; El-Maarry, M. R.; Groussin, O.; Capanna,
   C.; Jorda, L.; Bouley, S.; Davidsson, B.; Deller, J.; Güttler, C.;
   Hofmann, M.; Höfner, S.; Lamy, P. L.; Lazzarin, M.; Marchi, S.;
   Thomas, N.; Vincent, J. -B.; Sierks, H.
2015EPSC...10..516A    Altcode:
  Since August 2014, high spatial resolution images of the nucleus of
  67P/Churyumov-Gerasimenko have been acquired by the OSIRIS camera on
  board the Rosetta spacecraft, enabling to identify meter-scale features
  on the surface. Among them, we identify polygons with a size from 2
  to 20 meters. We define the polygons on 67P as high-centered thermal
  contraction polygons, which further evolve through preferential
  sublimation along the cracks. This kind of polygons are known on
  Earth and Mars as evidences of permanent water ice table in the near
  subsurface [1,2,3].

---------------------------------------------------------
Title: Characterization of the Subsurface of
    67P/Churyumov-Gerasimenko's Abydos Site
Authors: Brugger, B.; Mousis, O.; Morse, A.; Marboeuf, U.; Jorda, L.;
   Andrews, D.; Barber, S.; Guilbert-Lepoutre, A.; Lamy, P.; Luspay-Kuti,
   A.; Mandt, K.; Morgan, G.; Sheridan, S.; Vernazza, P.; Wright, I. P.
2015EPSC...10..206B    Altcode:
  We investigate the structure of the subsurface of the Abydos site
  using a cometary nucleus model with parameters adapted to comet
  67P/Churyumov- Gerasimenko and the Abydos landing site. We aim to
  compare the production rates derived from our model with those of the
  main molecules measured by Ptolemy. This will allow us to retrieve
  the depths at which the different molecules still exist in solid form.

---------------------------------------------------------
Title: A Novel Technique for Measuring the Solar Radius from Eclipse
    Light Curves - Results for 2010, 2012, 2013, and 2015
Authors: Lamy, Philippe; Prado, Jean-Yves; Floyd, Olivier; Rocher,
   Patrick; Faury, Guillaume; Koutchmy, Serge
2015SoPh..290.2617L    Altcode: 2015SoPh..tmp..170L
  We report on a novel technique for measuring the solar radius during
  total solar eclipses that exploits light curves recorded just before
  and after second and third contacts. The measurements are performed by
  pre-programmed photometers that are deployed over the eclipse paths and
  are operated without supervision. The recorded light curves are compared
  to synthetic light curves calculated from high-accuracy ephemerides
  and lunar-limb profiles constructed from the topographic model of the
  Moon provided by the Kaguya lunar space mission. A minimization process
  between the two sets of curves yields the solar radius. Altogether,
  seventeen determinations have been obtained during the past four total
  eclipses with the following averages (at a wavelength of 540 nm and
  scaled to 1 AU): 959.94 ±0.02 arcsec on 11 July 2010, 960.02 ±0.04
  arcsec on 13 November 2012, 959.99 ±0.09 arcsec on 3 November 2013, and
  960.01 ±0.09 arcsec on 20 March 2015. Part of the differences between
  these four values may be attributed to weather conditions. Averaging
  the whole set of measurements yields a radius of 959.99 ±0.06 arcsec
  (696 ,246 ±45 km), which agrees excellently well with the most recent
  data and supports an upward revision of the standard IAU value, as
  previously suggested.

---------------------------------------------------------
Title: Design and modelisation of ASPIICS optics
Authors: Galy, C.; Fineschi, S.; Galano, D.; Howard, R. A.; Kintziger,
   C.; Kirschner, V.; Koutchmy, S.; Lamy, P.; Mazzoli, A.; Melich, R.;
   Mestreau-Garreau, A.; Renotte, E.; Servaye, J. S.; Stockman, Y.;
   Thizy, C.; Zhukov, A.
2015SPIE.9604E..0BG    Altcode:
  In the framework of development of ASPIICS (Association of Spacecraft
  for Polarimetric and Imaging Investigation of the Corona of the Sun),
  the Centre Spatial de Liege is responsible of the optical design of
  the coronagraph and the optics will be manufactured by TOPTEC. The
  particularity of this coronagraph is to have an external occulter
  located 150 m ahead of the first imaging lens. This external occulter
  is re-imaged on an internal occulter which function is - as in a
  classical externally occulted Lyot coronagraph - to block the sun
  light diffracted by the external occulter and to reduce the straylight
  on the detector. The selection of this configuration is driven by the
  requirement to observe the corona as close as possible to the solar limb
  (i.e. 1 R<SUB>Sun</SUB>) without imaging the limb itself. A requirement
  of 1.08 R<SUB>Sun</SUB> is specified at optical design level to grant
  1.2 R<SUB>sun</SUB> at instrument level. The coronograph instrument is
  designed to have a field of view of 1.6° x 1.6° with a resolution of
  less than 6 arcsec. Its performances are limited by diffraction in a
  530 - 590 nm wavelength range. This paper presents the optical design
  and demonstrates that by design the requirements are fulfilled within
  the misalignment, manufacturing and thermo-elastic error contributions.

---------------------------------------------------------
Title: Design status of ASPIICS, an externally occulted coronagraph
    for PROBA-3
Authors: Renotte, Etienne; Alia, Andres; Bemporad, Alessandro;
   Bernier, Joseph; Bramanti, Cristina; Buckley, Steve; Capobianco,
   Gerardo; Cernica, Ileana; Dániel, Vladimir; Darakchiev, Radoslav;
   Darmetko, Marcin; Debaize, Arnaud; Denis, François; Desselle,
   Richard; de Vos, Lieve; Dinescu, Adrian; Fineschi, Silvano;
   Fleury-Frenette, Karl; Focardi, Mauro; Fumel, Aurélie; Galano,
   Damien; Galy, Camille; Gillis, Jean-Marie; Górski, Tomasz; Graas,
   Estelle; Graczyk, Rafał; Grochowski, Konrad; Halain, Jean-Philippe
   A.; Hermans, Aline; Howard, Russ; Jackson, Carl; Janssen, Emmanuel;
   Kasprzyk, Hubert; Kosiec, Jacek; Koutchmy, Serge; Kovačičinová,
   Jana; Kranitis, Nektarios; Kurowski, Michał; Ładno, Michał; Lamy,
   Philippe; Landini, Federico; Lapáček, Radek; Lédl, Vít.; Liebecq,
   Sylvie; Loreggia, Davide; McGarvey, Brian; Massone, Giuseppe; Melich,
   Radek; Mestreau-Garreau, Agnes; Mollet, Dominique; Mosdorf, Łukasz;
   Mosdorf, Michał; Mroczkowski, Mateusz; Muller, Raluca; Nicolini,
   Gianalfredo; Nicula, Bogdan; O'Neill, Kevin; Orleański, Piotr;
   Palau, Marie-Catherine; Pancrazzi, Maurizio; Paschalis, Antonios;
   Patočka, Karel; Peresty, Radek; Popescu, Irina; Psota, Pavel; Rataj,
   Miroslaw; Rautakoski, Jan; Romoli, Marco; Rybecký, Roman; Salvador,
   Lucas; Servaye, Jean-Sébastien; Solomon, Cornel; Stockman, Yvan;
   Swat, Arkadiusz; Thizy, Cédric; Thomé, Michel; Tsinganos, Kanaris;
   Van der Meulen, Jim; Van Vooren, Nico; Vit, Tomáš; Walczak, Tomasz;
   Zarzycka, Alicja; Zender, Joe; Zhukov, Andrei
2015SPIE.9604E..0AR    Altcode:
  The "sonic region" of the Sun corona remains extremely difficult to
  observe with spatial resolution and sensitivity sufficient to understand
  the fine scale phenomena that govern the quiescent solar corona,
  as well as phenomena that lead to coronal mass ejections (CMEs),
  which influence space weather. Improvement on this front requires
  eclipse-like conditions over long observation times. The space-borne
  coronagraphs flown so far provided a continuous coverage of the external
  parts of the corona but their over-occulting system did not permit to
  analyse the part of the white-light corona where the main coronal mass
  is concentrated. The proposed PROBA-3 Coronagraph System, also known
  as ASPIICS (Association of Spacecraft for Polarimetric and Imaging
  Investigation of the Corona of the Sun), with its novel design, will
  be the first space coronagraph to cover the range of radial distances
  between ~1.08 and 3 solar radii where the magnetic field plays a crucial
  role in the coronal dynamics, thus providing continuous observational
  conditions very close to those during a total solar eclipse. PROBA-3
  is first a mission devoted to the in-orbit demonstration of precise
  formation flying techniques and technologies for future European
  missions, which will fly ASPIICS as primary payload. The instrument
  is distributed over two satellites flying in formation (approx. 150m
  apart) to form a giant coronagraph capable of producing a nearly perfect
  eclipse allowing observing the sun corona closer to the rim than ever
  before. The coronagraph instrument is developed by a large European
  consortium including about 20 partners from 7 countries under the
  auspices of the European Space Agency. This paper is reviewing the
  recent improvements and design updates of the ASPIICS instrument as
  it is stepping into the detailed design phase.

---------------------------------------------------------
Title: Mid-Term Quasi-Periodicities and Solar Cycle Variation of
    the White-Light Corona from 18.5 Years (1996.0 - 2014.5) of LASCO
    Observations
Authors: Barlyaeva, T.; Lamy, P.; Llebaria, A.
2015SoPh..290.2117B    Altcode: 2015SoPh..tmp..106B
  We report on the analysis of the temporal evolution of the solar corona
  based on 18.5 years (1996.0 - 2014.5) of white-light observations
  with the SOHO/LASCO-C2 coronagraph. This evolution is quantified by
  generating spatially integrated values of the K-corona radiance, first
  globally, then in latitudinal sectors. The analysis considers time
  series of monthly values and 13-month running means of the radiance
  as well as several indices and proxies of solar activity. We study
  correlation, wavelet time-frequency spectra, and cross-coherence and
  phase spectra between these quantities. Our results give a detailed
  insight on how the corona responds to solar activity over timescales
  ranging from mid-term quasi-periodicities (also known as quasi-biennial
  oscillations or QBOs) to the long-term 11 year solar cycle. The
  amplitude of the variation between successive solar maxima and minima
  (modulation factor) very much depends upon the strength of the cycle
  and upon the heliographic latitude. An asymmetry is observed during the
  ascending phase of Solar Cycle 24, prominently in the royal and polar
  sectors, with north leading. Most prominent QBOs are a quasi-annual
  period during the maximum phase of Solar Cycle 23 and a shorter period,
  seven to eight months, in the ascending and maximum phases of Solar
  Cycle 24. They share the same properties as the solar QBOs: variable
  periodicity, intermittency, asymmetric development in the northern and
  southern solar hemispheres, and largest amplitudes during the maximum
  phase of solar cycles. The strongest correlation of the temporal
  variations of the coronal radiance - and consequently the coronal
  electron density - is found with the total magnetic flux. Considering
  that the morphology of the solar corona is also directly controlled by
  the topology of the magnetic field, this correlation reinforces the
  view that they are intimately connected, including their variability
  at all timescales.

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Title: Large heterogeneities in comet 67P as revealed by active pits
    from sinkhole collapse
Authors: Vincent, Jean-Baptiste; Bodewits, Dennis; Besse, Sébastien;
   Sierks, Holger; Barbieri, Cesare; Lamy, Philippe; Rodrigo, Rafael;
   Koschny, Detlef; Rickman, Hans; Keller, Horst Uwe; Agarwal, Jessica;
   A'Hearn, Michael F.; Auger, Anne-Thérèse; Barucci, M. Antonella;
   Bertaux, Jean-Loup; Bertini, Ivano; Capanna, Claire; Cremonese,
   Gabriele; da Deppo, Vania; Davidsson, Björn; Debei, Stefano; de Cecco,
   Mariolino; El-Maarry, Mohamed Ramy; Ferri, Francesca; Fornasier, Sonia;
   Fulle, Marco; Gaskell, Robert; Giacomini, Lorenza; Groussin, Olivier;
   Guilbert-Lepoutre, Aurélie; Gutierrez-Marques, P.; Gutiérrez, Pedro
   J.; Güttler, Carsten; Hoekzema, Nick; Höfner, Sebastian; Hviid,
   Stubbe F.; Ip, Wing-Huen; Jorda, Laurent; Knollenberg, Jörg; Kovacs,
   Gabor; Kramm, Rainer; Kührt, Ekkehard; Küppers, Michael; La Forgia,
   Fiorangela; Lara, Luisa M.; Lazzarin, Monica; Lee, Vicky; Leyrat,
   Cédric; Lin, Zhong-Yi; Lopez Moreno, Josè J.; Lowry, Stephen; Magrin,
   Sara; Maquet, Lucie; Marchi, Simone; Marzari, Francesco; Massironi,
   Matteo; Michalik, Harald; Moissl, Richard; Mottola, Stefano; Naletto,
   Giampiero; Oklay, Nilda; Pajola, Maurizio; Preusker, Frank; Scholten,
   Frank; Thomas, Nicolas; Toth, Imre; Tubiana, Cecilia
2015Natur.523...63V    Altcode:
  Pits have been observed on many cometary nuclei mapped by
  spacecraft. It has been argued that cometary pits are a signature
  of endogenic activity, rather than impact craters such as those
  on planetary and asteroid surfaces. Impact experiments and models
  cannot reproduce the shapes of most of the observed cometary pits,
  and the predicted collision rates imply that few of the pits are
  related to impacts. Alternative mechanisms like explosive activity
  have been suggested, but the driving process remains unknown. Here
  we report that pits on comet 67P/Churyumov-Gerasimenko are active,
  and probably created by a sinkhole process, possibly accompanied
  by outbursts. We argue that after formation, pits expand slowly in
  diameter, owing to sublimation-driven retreat of the walls. Therefore,
  pits characterize how eroded the surface is: a fresh cometary surface
  will have a ragged structure with many pits, while an evolved surface
  will look smoother. The size and spatial distribution of pits imply
  that large heterogeneities exist in the physical, structural or
  compositional properties of the first few hundred metres below the
  current nucleus surface.

---------------------------------------------------------
Title: Fractures on comet 67P/Churyumov-Gerasimenko observed by
    Rosetta/OSIRIS
Authors: El-Maarry, M. R.; Thomas, N.; Gracia-Berná, A.; Marschall,
   R.; Auger, A. -T.; Groussin, O.; Mottola, S.; Pajola, M.; Massironi,
   M.; Marchi, S.; Höfner, S.; Preusker, F.; Scholten, F.; Jorda, L.;
   Kührt, E.; Keller, H. U.; Sierks, H.; A'Hearn, M. F.; Barbieri, C.;
   Barucci, M. A.; Bertaux, J. -L.; Bertini, I.; Cremonese, G.; Da Deppo,
   V.; Davidsson, B.; Debei, S.; De Cecco, M.; Deller, J.; Güttler, C.;
   Fornasier, S.; Fulle, M.; Gutierrez, P. J.; Hofmann, M.; Hviid, S. F.;
   Ip, W. -H.; Knollenberg, J.; Koschny, D.; Kovacs, G.; Kramm, J. -R.;
   Küppers, M.; Lamy, P. L.; Lara, L. M.; Lazzarin, M.; Lopez Moreno,
   J. J.; Marzari, F.; Michalik, H.; Naletto, G.; Oklay, N.; Pommerol,
   A.; Rickman, H.; Rodrigo, R.; Tubiana, C.; Vincent, J. -B.
2015GeoRL..42.5170E    Altcode:
  The Optical, Spectroscopic, and Infrared Remote Imaging System
  (OSIRIS) experiment onboard the Rosetta spacecraft currently orbiting
  comet 67P/Churyumov-Gerasimenko has yielded unprecedented views
  of a comet's nucleus. We present here the first ever observations
  of meter-scale fractures on the surface of a comet. Some of these
  fractures form polygonal networks. We present an initial assessment of
  their morphology, topology, and regional distribution. Fractures are
  ubiquitous on the surface of the comet's nucleus. Furthermore, they
  occur in various settings and show different topologies suggesting
  numerous formation mechanisms, which include thermal insulation
  weathering, orbital-induced stresses, and possibly seasonal thermal
  contraction. However, we conclude that thermal insolation weathering
  is responsible for creating most of the observed fractures based on
  their morphology and setting in addition to thermal models that indicate
  diurnal temperature ranges exceeding 200 K and thermal gradients of ~15
  K/min at perihelion are possible. Finally, we suggest that fractures
  could be a facilitator in surface evolution and long-term erosion.

---------------------------------------------------------
Title: GIADA on-board Rosetta: comet 67P/C-G dust coma
    characterization
Authors: Rotundi, Alessandra; Della Corte, Vincenzo; Fulle, Marco;
   Sordini, Roberto; Ivanovski, Stavro; Accolla, Mario; Ferrari, Marco;
   Lucarelli, Francesca; Zakharov, Vladimir; Mazzotta Epifani, Elena;
   López-Moreno, José J.; Rodríguez, Julio; Colangeli, Luigi; Palumbo,
   Pasquale; Bussoletti, Ezio; Crifo, Jean-Francois; Esposito, Francesca;
   Green, Simon F.; Grün, Eberhard; Lamy, Philippe L.
2015EGUGA..1713156R    Altcode:
  21ESA-ESAC, Camino Bajo del Castillo, s/n., Urb. Villafranca del
  Castillo, 28692 Villanueva de la Cañada, Madrid, Spagna GIADA
  consists of three subsystems: 1) the Grain Detection System (GDS)
  to detect dust grains as they pass through a laser curtain, 2)
  the Impact Sensor (IS) to measure grain momentum derived from the
  impact on a plate connected to five piezoelectric sensors, and 3)
  the MicroBalances System (MBS); five quartz crystal microbalances in
  roughly orthogonal directions providing the cumulative dust flux of
  grains smaller than 10 microns. GDS provides data on grain speed and its
  optical cross section. The IS grain momentum measurement, when combined
  with the GDS detection time, provides a direct measurement of grain
  speed and mass. These combined measurements characterize single grain
  dust dynamics in the coma of 67P/CG. No prior in situ dust dynamical
  measurements at these close distances from the nucleus and starting from
  such high heliocentric distances are available up to date. We present
  here the results obtained by GIADA, which began operating in continuous
  mode on 18 July 2014 when the comet was at a heliocentric distance of
  3.7 AU. The first grain detection occurred when the spacecraft was
  814 km from the nucleus on 1 August 2014. From August the 1st up to
  December the 11th, GIADA detected more than 800 grains, for which the
  3D spatial distribution was determined. About 700 out of 800 are GDS
  only detections: "dust clouds", i.e. slow dust grains (≈ 0.5 m/s)
  crossing the laser curtain very close in time (e.g. 129 grains in 11
  s), probably fluffy grains. IS only detections are about 70, i.e. ≈
  1/10 of the GDS only. This ratio is quite different from what we got
  for the early detections (August - September) when the ration was ≈
  3, suggesting the presence of different types of particle (bigger,
  brighter, less dense).The combined GDS+IS detections, i.e. measured by
  both the GDS and IS detectors, are about 70 and allowed us to extract
  the complete set of dust grain parameters, i.e., mass, speed, and
  geometrical cross-section. These detections allowed us to constraint the
  grain density. The GIADA detections type was studied as a function of
  the observational geometrical configuration. Acknowledgments: GIADA was
  built by a consortium led by the Univ. Napoli "Parthenope" &amp; INAF-
  Oss. Astr. Capodimonte, in collaboration with the Inst. de Astrofisica
  de Andalucia, Selex-ES, FI and SENER. GIADA is presently managed
  &amp; operated by Ist. di Astrofisica e Planetologia Spaziali-INAF,
  IT. GIADA was funded and managed by the Agenzia Spaziale Italiana,
  IT, with the support of the Spanish Ministry of Education and Science
  MEC, ES. GIADA was developed from a PI proposal from the University
  of Kent; sci. &amp; tech. contribution were provided by CISAS, IT,
  Lab. d'Astr. Spat., FR, and Institutions from UK, IT, FR, DE and USA. We
  thank the RSGS/ESAC, RMOC/ESOC &amp; Rosetta Project/ESTEC for their
  outstanding work. Science support provided was by NASA through the US
  Rosetta Project managed by the Jet Propulsion Laboratory/California
  Institute of Technology. GIADA calibrated data will be available through
  ESA's PSA web site (www.rssd.esa.int/index.php?project=PSA&amp;page=in
  dex). We would like to thank Angioletta Coradini for her contribution
  as a GIADA Co-I.

---------------------------------------------------------
Title: Rosetta/OSIRIS - Nucleus morphology and activity of comet
    67P/Churyumov-Gerasimenko
Authors: Sierks, Holger; Barbieri, Cesare; Lamy, Philippe; Rickman,
   Hans; Rodrigo, Rafael; Koschny, Detlef
2015EGUGA..1712760S    Altcode:
  ESA's Rosetta mission arrived on August 6, 2014, at target comet
  67P/Churyumov-Gerasimenko after 10 years of cruise. OSIRIS (Optical,
  Spectroscopic, and Infrared Remote Imaging System) is the scientific
  imaging system onboard Rosetta. It comprises a Narrow Angle Camera
  (NAC) for nucleus surface and dust studies and a Wide Angle Camera
  (WAC) for the wide field coma investigations. OSIRIS imaged the nucleus
  and coma of the comet from the arrival throughout the mapping phase,
  PHILAE landing, early escort phase and close fly-by. The overview paper
  will discuss the surface morpholo-gy and activity of the nucleus as
  seen in gas, dust, and local jets as well as small scale structures
  in the local topography.

---------------------------------------------------------
Title: Morphology of the nucleus of Comet 67P/Churyumov-Gerasimenko
    from stereo and high spatial resolution OSIRIS-NAC images
Authors: Lamy, Philippe; Groussin, Olivier; Romeuf, David; Thomas,
   Nicolas; Auger, Anne-Thérèse; Jorda, Laurent; Gaskell, Robert;
   Capanna, Claire; Llebaria, Antoine
2015EGUGA..17.8338L    Altcode:
  The Narrow Angle Camera (NAC) of the OSIRIS imaging system aboard ESA's
  Rosetta spacecraft has acquired images of the surface of the nucleus
  of comet 67P/Churyumov-Gerasimenko at scales down to 0.2 m/pixel. We
  employ a variety of techniques to characterize its morphology. Digital
  terrain modeling (DTM), indispensable for quantitative morphological
  analysis is performed using stereophotoclinometry (SPC). Depending upon
  the observational coverage, the resolution of the DTMs exceed 1 m in the
  most favorable cases. The ultimate stereographic analysis is performed
  by exploiting pairs of images able to produce anaglyphs whose spatial
  resolution surpasses that of the DTMs. Digital image filtering and
  contrast enhancement techniques are applied on the original images as
  appropriate. We first concentrate on the dust covered terrains possibly
  resulting from airfall deposits, on the quasi-circular depressions or
  basins possibly connected to collapses of the underground terrain,
  and on large scarps that suggest extensive mass disruption. We pay
  special attention to lithologies that may give clues to the subsurface
  structure of the nucleus. Our ultimate goal is to understand the
  processes at work on the nucleus, directly or indirectly connected to
  its activity as there appears to a variety of processes far beyond what
  was classicaly considered in the past, for instance airfall deposits,
  surface dust transport, mass wasting, and insolation weathering.

---------------------------------------------------------
Title: A New 3D Shape Reconstruction Method for celestial bodies:
    Multi-Resolution Stereophotoclinometry by Deformation
Authors: Capanna, Claire; Jorda, Laurent; Gesquière, Gilles; Groussin,
   Olivier; Gutiérrez, Pedro; Hviid, Stubbe; Lamy, Philippe; Rodionov,
   Sergey; Vibert, Didier
2015EGUGA..17.5343C    Altcode:
  In astrophysics, direct measures on celestial bodies are not always
  feasible. 3D shape models allow to overcome this kind of problem. We
  thus developed a new 3D shape reconstruction method which combines
  stereo, photoclinometry and the deformation of a triangular mesh
  describing the surface of the object. The method deforms the mesh -
  initially a sphere - until the set of synthetic images, created from the
  mesh (Jorda et al., SPIE 2010) match the observed one. Stereo control
  points can be used as a constraint in the deformation of the mesh,
  but it is not required at low resolutions. This new technique has been
  applied to images of the nucleus of comet 67P/Churyumov-Gerasimenko
  acquired by the OSIRIS instrument aboard the Rosetta spacecraft. It
  allowed to reconstruct the shape of the nucleus and to retrieve its
  rotational parameters from low-resolution images obtained with the
  narrow-angle camera of OSIRIS in mid-July 2014, when stereo-based
  techniques were still inapplicable. The technique has also been applied
  to higher-resolution images of the nucleus later on, using the stereo
  information as a constraint.

---------------------------------------------------------
Title: Monitoring Comet 67P/C-G Micrometer Dust Flux: GIADA onboard
    Rosetta.
Authors: Della Corte, Vincenzo; Rotundi, Alessandra; Ivanovski,
   Stavro; Accolla, Mario; Ferrari, Marco; Sordini, Roberto; Lucarelli,
   Francesca; Zakharov, Vladimir; Fulle, Marco; Mazzotta Epifani, Elena;
   López-Moreno, José J.; Rodríguez, Julio; Colangeli, Luigi; Palumbo,
   Pasquale; Bussoletti, Ezio; Crifo, Jean-Francois; Esposito, Francesca;
   Green, Simon F.; Grün, Eberhard; Lamy, Philippe L.
2015EGUGA..17.6559D    Altcode:
  (21)ESA-ESAC, Camino Bajo del Castillo, s/n., Urb. Villafranca
  del Castillo, 28692 Villanueva de la Cañada, Madrid, Spagna The
  MicroBalance System (MBS) is one of the three measurement subsystems
  of GIADA, the Grain Impact Analyzer and Dust Accumulator on board
  the Rosetta/ESA spacecraft (S/C). It consists of five Quartz Crystal
  Microbalances (QCMs) in roughly orthogonal directions providing
  the cumulative dust flux of grains smaller than 10 microns. The MBS
  is continuously monitoring comet 67P/CG since the beginning of May
  2014. During the first 4 months of measurements, before the insertion
  of the S/C in the bound orbit phase, there were no evidences of dust
  accumulation on the QCMs. Starting from the beginning of October,
  three out of five QCMs measured an increase of the deposited dust. The
  measured fluxes show, as expected, a strong anisotropy. In particular,
  the dust flux appears to be much higher from the Sun direction with
  respect to the comet direction. Acknowledgment: GIADA was built
  by a consortum led by the Univ. Napoli "Parthenope" &amp; INAF-
  Oss. Astr. Capodimonte, in collaboration with the Inst. de Astrofisica
  de Andalucia, Selex-ES, FI and SENER. GIADA is presently managed
  &amp; operated by Ist. di Astrofisica e Planetologia Spaziali-INAF,
  IT. GIADA was funded and managed by the Agenzia Spaziale Italiana,
  IT, with the support of the Spanish Ministry of Education and Science
  MEC, ES. GIADA was developed from a PI proposal from the University
  of Kent; sci. &amp; tech. contribution were provided by CISAS, IT,
  Lab. d'Astr. Spat., FR, and Institutions from UK, IT, FR, DE and USA. We
  thank the RSGS/ESAC, RMOC/ESOC &amp; Rosetta Project/ESTEC for their
  out-standing work. Science support provided was by NASA through the US
  Rosetta Project managed by the Jet Propulsion Laboratory/ California
  Institute of Technology. GIADA calibrated data will be available through
  ESA's PSA web site (www.rssd.esa.int/index.php? project=PSA&amp;page=in
  dex). We would like to thank Angioletta Coradini for her contribution
  as a GIADA Co-I.

---------------------------------------------------------
Title: Dust Measurements in the Coma of Comet
    67P/Churyumov-Gerasimenko Inbound to the Sun Between 3.7 and 3.4 AU
Authors: Rotundi, Alessandra; Della Corte, Vincenzo; Fulle, Marco;
   Ferrari, Marco; Sordini, Roberto; Ivanovski, Stavro; Accolla, Mario;
   Lucarelli, Francesca; Zakharov, Vladimir; Mazzotta Epifani, Elena;
   López-Moreno, José J.; Rodríguez, Julio; Colangeli, Luigi; Palumbo,
   Pasquale; Bussoletti, Ezio; Crifo, Jean-Francois; Esposito, Francesca;
   Green, Simon F.; Grün, Eberhard; Lamy, Philippe L.
2015EGUGA..1712907R    Altcode:
  (21) ESA-ESAC, Camino Bajo del Castillo, s/n., Urb. Villafranca del
  Castillo, 28692 Villanueva de la Cañada, Madrid, Spagna, (22) Max
  Planck Institute for Solar System Research, Justus-von-Liebig-Weg 3,
  37077 Göttingen, Germany, (23) Center of Studies and Activities
  for Space (CISAS), University of Padova, I-35131 Padova, Italy,
  (24) Department of Physics and Astronomy, University of Padova,
  I-35131 Padova, Italy Comets are the most primitive bodies in the
  solar system. They retain a cosmo-chemical record of conditions in
  the solar nebula when the planets were forming, 4.5 billion years
  ago. While accurate measurements of the gas loss rate from comets are
  possible under favorable conditions even from Earth, estimates of the
  dust loss rate so far have been much more uncertain. Multi-parametric
  models are needed to extract global dust parameters from the dust
  features of comets (e.g. coma, tails and trails) observed from
  ground and Earth orbiting telescopes, and it is often difficult to
  establish the uniqueness of these model results. Critical measurements
  for understanding the process of accretion and the refractory to
  volatiles ratio in the solar nebula are being obtained by the Grain
  Impact Analyzer and Dust Accumulator (GIADA) experiment onboard ESA's
  Rosetta spacecraft, now orbiting comet 67P/Churyumov-Gerasimenko
  (67P/CG). GIADA measures the mass, momentum and velocity of individual
  grains, providing the dust loss rate over three orders of magnitude in
  mass for grains from tens to hundreds of microns in diameter. GIADA
  consists of three subsystems: 1) the Grain Detection System (GDS) to
  detect dust grains as they pass through a laser curtain, 2) the Impact
  Sensor (IS) to measure grain momentum derived from the impact on a
  plate connected to five piezoelectric sensors, and 3) the Mi-croBalances
  System (MBS); five quartz crystal microbalances in roughly orthogonal
  directions providing the cumu-lative dust flux of grains smaller
  than 10 microns. GDS provides data on grain speed and its optical
  cross section. The IS grain momentum measurement, when combined with
  the GDS detection time, provides a direct measurement of grain speed
  and mass. These combined measurements characterize single grain dust
  dynamics in the coma of 67P/CG. The first grain was detected on 1 August
  2014 at 814 km from the comet nucleus. Between then and 13 Septem-ber
  2014 GIADA detected 35 grains ranging in mass from ~ 5 x 10-10 to 8
  x 10-8 kg. Including complementary data from the OSIRIS narrow angle
  camera, the dust mass loss was calculated over an additional three
  orders of magni-tude in mass, extending the ejected dust grain sizes up
  to 2 cm. Combined with data from the MIRO and the ROSINA instruments
  onboard Rosetta we find a dust/gas mass ratio of 4 +/- 2 averaged
  over the sunlit nucleus sur-face. The dust to gas ratio may change
  as the comet approaches closer to the Sun. Acknowledgments: GIADA was
  built by a consortium led by the Univ. Napoli "Parthenope" &amp; INAF-
  Oss. Astr. Capodimonte, in collabo-ration with the Inst. de Astrofisica
  de Andalucia, Selex-ES, FI and SENER. GIADA is presently managed
  &amp; operated by Ist. di Astrofisica e Planetologia Spaziali-INAF,
  IT. GIADA was funded and managed by the Agenzia Spaziale Italiana,
  IT, with the support of the Spanish Ministry of Education and Science
  MEC, ES. GIADA was developed from a PI proposal from the University
  of Kent; sci. &amp; tech. contribution were pro-vided by CISAS, IT,
  Lab. d'Astr. Spat., FR, and Institutions from UK, IT, FR, DE and USA. We
  thank the RSGS/ESAC, RMOC/ESOC &amp; Rosetta Project/ESTEC for their
  outstanding work. Science support provided was by NASA through the US
  Rosetta Project managed by the Jet Propulsion Laboratory/California
  Institute of Technology. GIADA calibrated data will be available through
  ESA's PSA web site(www.rssd.esa.int/index.php?project=PSA&amp;page=in
  dex). We would like to thank Angioletta Coradini for her contribution
  as a GIADA Co-I. We thank the MIRO, OSIRIS and ROSINA teams for sharing
  their early results with us.

---------------------------------------------------------
Title: Low and High Albedo Jovian Trojans and Hildas: A Similar or
    Different Origin?
Authors: Marsset, M.; Vernazza, P.; Gourgeot, F.; Dumas, C.; Birlan,
   M.; Lamy, P.; Binzel, R. P.
2015LPI....46.1860M    Altcode: 2015LPICo1832.1860M
  We report the first spectroscopic characterization of a sample of high
  albedo Trojans and Hildas.

---------------------------------------------------------
Title: Dust Measurements in the Coma of Comet
    67P/Churyumov-Gerasimenko Inbound to the Sun Between 3.7 and 3.4 AU
Authors: Fulle, M.; Della Corte, V.; Rotundi, A.; Accolla, M.;
   Ferrari, M.; Ivanovski, S.; Lucarelli, F.; Sordini, R.; Zakharov, V.;
   Mazzotta Epifani, E.; Lopez-Moreno, J. J.; Rodriguez, J.; Colangeli,
   L.; Palumbo, P.; Bussoletti, E.; Crifo, J.; Esposito, F.; Green,
   S. F.; Gruen, E.; Lamy, P. L.; McDonnell, J. A. M.; Mennella, V.;
   Molina, A.; Morales, R.; Moreno, F.; Ortiz, J. L.; Palomba, E.;
   Perrin, J.; Rodrigo, R.; Weissman, P.; Zarnecki, J. C.; Cosi, M.;
   Giovane, F.; Gustafson, B.; Herranz, M. L.; Jeronimo, J. M.; Leese,
   M. R.; Lopez-Jimenez, A. C.; Altobelli, N.; Sierks, H.; Agarwal, J.;
   Bertini, I.; Fornasier, S.; Gutierrez, P. J.; Lara, L.; Guettler, C.;
   Marzari, F.; Oaklay, N.; Snodgrass, C.; Tubiana, C.; Vincenzo, J. B.
2015LPI....46.2420F    Altcode: 2015LPICo1832.2420F
  GIADA and OSIRIS dust data, combined with data from MIRO and ROSINA
  instruments onboard Rosetta, from 3.7 to 3.4 AU inbound provide a
  dust/gas ratio of 4 ± 2.

---------------------------------------------------------
Title: The Geomorphology of Comet 67P: Implications for the Past
    Collisional Evolution and Formation
Authors: Marchi, S.; Rickman, H.; Massironi, M.; Marzari, F.; El-Maari,
   M. R.; Besse, S.; Thomas, N.; Barbieri, C.; Barucci, M. A.; Fornasier,
   S.; Giacomini, L.; Keller, H. U.; Kuehrt, E.; Lamy, P.; Lazzarin,
   M.; Mottola, S.; Naletto, G.; Pajola, M.; Sierks, H.
2015LPI....46.1532M    Altcode: 2015LPICo1832.1532M
  OSIRIS camera onboard Rosetta showed Comet 67P complex surface,
  characterized by fractures and layering. We discuss their implications
  for 67P formation.

---------------------------------------------------------
Title: Density and Charge of Pristine Fluffy Particles from Comet
    67P/Churyumov-Gerasimenko
Authors: Fulle, M.; Della Corte, V.; Rotundi, A.; Weissman, P.; Juhasz,
   A.; Szego, K.; Sordini, R.; Ferrari, M.; Ivanovski, S.; Lucarelli,
   F.; Accolla, M.; Merouane, S.; Zakharov, V.; Mazzotta Epifani, E.;
   López-Moreno, J. J.; Rodríguez, J.; Colangeli, L.; Palumbo, P.;
   Grün, E.; Hilchenbach, M.; Bussoletti, E.; Esposito, F.; Green,
   S. F.; Lamy, P. L.; McDonnell, J. A. M.; Mennella, V.; Molina, A.;
   Morales, R.; Moreno, F.; Ortiz, J. L.; Palomba, E.; Rodrigo, R.;
   Zarnecki, J. C.; Cosi, M.; Giovane, F.; Gustafson, B.; Herranz, M. L.;
   Jerónimo, J. M.; Leese, M. R.; López-Jiménez, A. C.; Altobelli, N.
2015ApJ...802L..12F    Altcode:
  The Grain Impact Analyzer and Dust Accumulator (GIADA) instrument on
  board ESA’s Rosetta mission is constraining the origin of the dust
  particles detected within the coma of comet 67 P/Churyumov-Gerasimenko
  (67P). The collected particles belong to two families: (i) compact
  particles (ranging in size from 0.03 to 1 mm), witnessing the presence
  of materials that underwent processing within the solar nebula and (ii)
  fluffy aggregates (ranging in size from 0.2 to 2.5 mm) of sub-micron
  grains that may be a record of a primitive component, probably linked to
  interstellar dust. The dynamics of the fluffy aggregates constrain their
  equivalent bulk density to \lt 1 kg m<SUP>-3</SUP>. These aggregates
  are charged, fragmented, and decelerated by the spacecraft negative
  potential and enter GIADA in showers of fragments at speeds \lt 1
  m s<SUP>-1</SUP>. The density of such optically thick aggregates
  is consistent with the low bulk density of the nucleus. The mass
  contribution of the fluffy aggregates to the refractory component of
  the nucleus is negligible and their coma brightness contribution is
  less than 15%.

---------------------------------------------------------
Title: Properties of craters on the Achaia region of Asteroid
    (21) Lutetia
Authors: Auger, A. -T.; Bouley, S.; Jorda, L.; Groussin, O.; Lamy,
   P. L.; Baratoux, D.
2015Icar..247..137A    Altcode:
  We report on the physical properties of the craters of Achaia region
  of the main-belt Asteroid (21) Lutetia, based on images obtained with
  the OSIRIS instrument during the Rosetta flyby that took place on 10
  July 2010. Images of the surface were acquired with its Narrow Angle
  Camera, from which Digital Terrain Models (DTM) of the surface were
  constructed. These DTMs give access to the geometrical properties of
  the craters of the asteroid. On a complex asteroid shape, slopes and
  depth-to-diameter ratios (d/D) of craters should be carefully measured
  taking into account the local topography to obtain a value that is
  physically related to the work of forces resisting to mass displacement
  (associated with gravity and/or material strength) occurring in either
  excavation or degradation processes. We present new measurements
  of d/D and internal slopes of impact craters of the Achaia region,
  which offers optimal conditions of observations and a large population
  of craters. We find that d/D values for Achaia craters differ from
  previous works on Lutetia and are consistent with the values found on
  other asteroids such as (243) Ida or (951) Gaspra. The Achaia region
  may be divided into three units based on geomorphological analysis. The
  mean d/D values of the three units are different, revealing differences
  in resurfacing history by impact-related ejecta blanketing and seismic
  shaking. Some of these geological events may be recent compared to the
  age of the region since several lineaments intersect most craters of
  one of the three units. Independent evidence for ejecta blanket have
  been given for the unit associated with low d/D values confirming
  the contribution of this process to crater modification. Moreover, we
  suggest that displacements along faults identified as surface lineaments
  may have been responsible for the erasure of small craters. Our results
  are finally integrated into a chronology sequence of events explaining
  the present characteristics of the Achaia region.

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Title: 67P/Churyumov-Gerasimenko: Activity between March and June
    2014 as observed from Rosetta/OSIRIS
Authors: Tubiana, C.; Snodgrass, C.; Bertini, I.; Mottola, S.; Vincent,
   J. -B.; Lara, L.; Fornasier, S.; Knollenberg, J.; Thomas, N.; Fulle,
   M.; Agarwal, J.; Bodewits, D.; Ferri, F.; Güttler, C.; Gutierrez,
   P. J.; La Forgia, F.; Lowry, S.; Magrin, S.; Oklay, N.; Pajola, M.;
   Rodrigo, R.; Sierks, H.; A'Hearn, M. F.; Angrilli, F.; Barbieri,
   C.; Barucci, M. A.; Bertaux, J. -L.; Cremonese, G.; Da Deppo, V.;
   Davidsson, B.; De Cecco, M.; Debei, S.; Groussin, O.; Hviid, S. F.;
   Ip, W.; Jorda, L.; Keller, H. U.; Koschny, D.; Kramm, R.; Kührt, E.;
   Küppers, M.; Lazzarin, M.; Lamy, P. L.; Lopez Moreno, J. J.; Marzari,
   F.; Michalik, H.; Naletto, G.; Rickman, H.; Sabau, L.; Wenzel, K. -P.
2015A&A...573A..62T    Altcode:
  <BR /> Aims: 67P/Churyumov-Gerasimenko is the target comet of the
  ESA's Rosetta mission. After commissioning at the end of March 2014,
  the Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS)
  onboard Rosetta, started imaging the comet and its dust environment to
  investigate how they change and evolve while approaching the Sun. <BR />
  Methods: We focused our work on Narrow Angle Camera (NAC) orange images
  and Wide Angle Camera (WAC) red and visible-610 images acquired between
  2014 March 23 and June 24 when the nucleus of 67P was unresolved and
  moving from approximately 4.3 AU to 3.8 AU inbound. During this period
  the 67P - Rosetta distance decreased from 5 million to 120 thousand
  km. <BR /> Results: Through aperture photometry, we investigated
  how the comet brightness varies with heliocentric distance. 67P was
  likely already weakly active at the end of March 2014, with excess
  flux above that expected for the nucleus. The comet's brightness was
  mostly constant during the three months of approach observations,
  apart from one outburst that occurred around April 30 and a second
  increase in flux after June 20. Coma was resolved in the profiles from
  mid-April. Analysis of the coma morphology suggests that most of the
  activity comes from a source towards the celestial north pole of the
  comet, but the outburst that occurred on April 30 released material
  in a different direction.

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Title: The morphological diversity of comet 67P/Churyumov-Gerasimenko
Authors: Thomas, Nicolas; Sierks, Holger; Barbieri, Cesare; Lamy,
   Philippe L.; Rodrigo, Rafael; Rickman, Hans; Koschny, Detlef; Keller,
   Horst Uwe; Agarwal, Jessica; A'Hearn, Michael F.; Angrilli, Francesco;
   Auger, Anne-Therese; Barucci, M. Antonella; Bertaux, Jean-Loup;
   Bertini, Ivano; Besse, Sebastien; Bodewits, Dennis; Cremonese,
   Gabriele; Da Deppo, Vania; Davidsson, Björn; De Cecco, Mariolino;
   Debei, Stefano; El-Maarry, Mohamed Ramy; Ferri, Francesca; Fornasier,
   Sonia; Fulle, Marco; Giacomini, Lorenza; Groussin, Olivier; Gutierrez,
   Pedro J.; Güttler, Carsten; Hviid, Stubbe F.; Ip, Wing-Huen; Jorda,
   Laurent; Knollenberg, Jörg; Kramm, J. -Rainer; Kührt, Ekkehard;
   Küppers, Michael; La Forgia, Fiorangela; Lara, Luisa M.; Lazzarin,
   Monica; Moreno, Josè J. Lopez; Magrin, Sara; Marchi, Simone;
   Marzari, Francesco; Massironi, Matteo; Michalik, Harald; Moissl,
   Richard; Mottola, Stefano; Naletto, Giampiero; Oklay, Nilda; Pajola,
   Maurizio; Pommerol, Antoine; Preusker, Frank; Sabau, Lola; Scholten,
   Frank; Snodgrass, Colin; Tubiana, Cecilia; Vincent, Jean-Baptiste;
   Wenzel, Klaus-Peter
2015Sci...347a0440T    Altcode: 2015Sci...347.0440T
  Images of comet 67P/Churyumov-Gerasimenko acquired by the OSIRIS
  (Optical, Spectroscopic and Infrared Remote Imaging System) imaging
  system onboard the European Space Agency’s Rosetta spacecraft at
  scales of better than 0.8 meter per pixel show a wide variety of
  different structures and textures. The data show the importance
  of airfall, surface dust transport, mass wasting, and insolation
  weathering for cometary surface evolution, and they offer some support
  for subsurface fluidization models and mass loss through the ejection
  of large chunks of material.

---------------------------------------------------------
Title: Dust measurements in the coma of comet
    67P/Churyumov-Gerasimenko inbound to the Sun
Authors: Rotundi, Alessandra; Sierks, Holger; Della Corte, Vincenzo;
   Fulle, Marco; Gutierrez, Pedro J.; Lara, Luisa; Barbieri, Cesare;
   Lamy, Philippe L.; Rodrigo, Rafael; Koschny, Detlef; Rickman, Hans;
   Keller, Horst Uwe; López-Moreno, José J.; Accolla, Mario; Agarwal,
   Jessica; A'Hearn, Michael F.; Altobelli, Nicolas; Angrilli, Francesco;
   Barucci, M. Antonietta; Bertaux, Jean-Loup; Bertini, Ivano; Bodewits,
   Dennis; Bussoletti, Ezio; Colangeli, Luigi; Cosi, Massimo; Cremonese,
   Gabriele; Crifo, Jean-Francois; Da Deppo, Vania; Davidsson, Björn;
   Debei, Stefano; De Cecco, Mariolino; Esposito, Francesca; Ferrari,
   Marco; Fornasier, Sonia; Giovane, Frank; Gustafson, Bo; Green,
   Simon F.; Groussin, Olivier; Grün, Eberhard; Güttler, Carsten;
   Herranz, Miguel L.; Hviid, Stubbe F.; Ip, Wing; Ivanovski, Stavro;
   Jerónimo, José M.; Jorda, Laurent; Knollenberg, Joerg; Kramm, Rainer;
   Kührt, Ekkehard; Küppers, Michael; Lazzarin, Monica; Leese, Mark R.;
   López-Jiménez, Antonio C.; Lucarelli, Francesca; Lowry, Stephen C.;
   Marzari, Francesco; Epifani, Elena Mazzotta; McDonnell, J. Anthony M.;
   Mennella, Vito; Michalik, Harald; Molina, Antonio; Morales, Rafael;
   Moreno, Fernando; Mottola, Stefano; Naletto, Giampiero; Oklay,
   Nilda; Ortiz, José L.; Palomba, Ernesto; Palumbo, Pasquale; Perrin,
   Jean-Marie; Rodríguez, Julio; Sabau, Lola; Snodgrass, Colin; Sordini,
   Roberto; Thomas, Nicolas; Tubiana, Cecilia; Vincent, Jean-Baptiste;
   Weissman, Paul; Wenzel, Klaus-Peter; Zakharov, Vladimir; Zarnecki,
   John C.
2015Sci...347a3905R    Altcode: 2015Sci...347.3905R
  Critical measurements for understanding accretion and the dust/gas
  ratio in the solar nebula, where planets were forming 4.5 billion
  years ago, are being obtained by the GIADA (Grain Impact Analyser
  and Dust Accumulator) experiment on the European Space Agency’s
  Rosetta spacecraft orbiting comet 67P/Churyumov-Gerasimenko. Between
  3.6 and 3.4 astronomical units inbound, GIADA and OSIRIS (Optical,
  Spectroscopic, and Infrared Remote Imaging System) detected 35
  outflowing grains of mass 10<SUP>-10</SUP> to 10<SUP>-7</SUP> kilograms,
  and 48 grains of mass 10<SUP>-5</SUP> to 10<SUP>-2</SUP> kilograms,
  respectively. Combined with gas data from the MIRO (Microwave Instrument
  for the Rosetta Orbiter) and ROSINA (Rosetta Orbiter Spectrometer for
  Ion and Neutral Analysis) instruments, we find a dust/gas mass ratio
  of 4 ± 2 averaged over the sunlit nucleus surface. A cloud of larger
  grains also encircles the nucleus in bound orbits from the previous
  perihelion. The largest orbiting clumps are meter-sized, confirming
  the dust/gas ratio of 3 inferred at perihelion from models of dust
  comae and trails.

---------------------------------------------------------
Title: Probing the Solar Wind Acceleration Region with the Sun-grazing
    Comet C/2002 S2
Authors: Giordano, S.; Raymond, J. C.; Lamy, P.; Uzzo, M.; Dobrzycka,
   D.
2015ApJ...798...47G    Altcode: 2014arXiv1411.1300G
  Comet C/2002 S2, a member of the Kreutz family of sungrazing comets, was
  discovered in white-light images of the Large Angle and Spectromeric
  Coronagraph Experiment coronagraph on the Solar and Heliospheric
  Observatory (SOHO) on 2002 September 18 and observed in H I Lyα
  emission by the SOHO Ultraviolet Coronagraph Spectrometer (UVCS)
  instrument at four different heights as it approached the Sun. The H
  I Lyα line profiles detected by UVCS are analyzed to determine the
  spectral parameters: line intensity, width, and Doppler shift with
  respect to the coronal background. Two-dimensional comet images of
  these parameters are reconstructed at the different heights. A novel
  aspect of the observations of this sungrazing comet data is that,
  whereas the emission from most of the tail is blueshifted, that along
  one edge of the tail is redshifted. We attribute these shifts to a
  combination of solar wind speed and interaction with the magnetic
  field. In order to use the comet to probe the density, temperature,
  and speed of the corona and solar wind through which it passes, as
  well as to determine the outgassing rate of the comet, we develop a
  Monte Carlo simulation of the H I Lyα emission of a comet moving
  through a coronal plasma. From the outgassing rate, we estimate a
  nucleus diameter of about 9 m. This rate steadily increases as the
  comet approaches the Sun, while the optical brightness decreases by
  more than a factor of 10 and suddenly recovers. This indicates that
  the optical brightness is determined by the lifetimes of the grains,
  sodium atoms, and molecules produced by the comet.

---------------------------------------------------------
Title: On the nucleus structure and activity of comet
    67P/Churyumov-Gerasimenko
Authors: Sierks, Holger; Barbieri, Cesare; Lamy, Philippe L.; Rodrigo,
   Rafael; Koschny, Detlef; Rickman, Hans; Keller, Horst Uwe; Agarwal,
   Jessica; A'Hearn, Michael F.; Angrilli, Francesco; Auger, Anne-Therese;
   Barucci, M. Antonella; Bertaux, Jean-Loup; Bertini, Ivano; Besse,
   Sebastien; Bodewits, Dennis; Capanna, Claire; Cremonese, Gabriele; Da
   Deppo, Vania; Davidsson, Björn; Debei, Stefano; De Cecco, Mariolino;
   Ferri, Francesca; Fornasier, Sonia; Fulle, Marco; Gaskell, Robert;
   Giacomini, Lorenza; Groussin, Olivier; Gutierrez-Marques, Pablo;
   Gutiérrez, Pedro J.; Güttler, Carsten; Hoekzema, Nick; Hviid, Stubbe
   F.; Ip, Wing-Huen; Jorda, Laurent; Knollenberg, Jörg; Kovacs, Gabor;
   Kramm, J. Rainer; Kührt, Ekkehard; Küppers, Michael; La Forgia,
   Fiorangela; Lara, Luisa M.; Lazzarin, Monica; Leyrat, Cédric; Lopez
   Moreno, Josè J.; Magrin, Sara; Marchi, Simone; Marzari, Francesco;
   Massironi, Matteo; Michalik, Harald; Moissl, Richard; Mottola, Stefano;
   Naletto, Giampiero; Oklay, Nilda; Pajola, Maurizio; Pertile, Marco;
   Preusker, Frank; Sabau, Lola; Scholten, Frank; Snodgrass, Colin;
   Thomas, Nicolas; Tubiana, Cecilia; Vincent, Jean-Baptiste; Wenzel,
   Klaus-Peter; Zaccariotto, Mirco; Pätzold, Martin
2015Sci...347a1044S    Altcode: 2015Sci...347.1044S
  Images from the OSIRIS scientific imaging system onboard Rosetta
  show that the nucleus of 67P/Churyumov-Gerasimenko consists of two
  lobes connected by a short neck. The nucleus has a bulk density less
  than half that of water. Activity at a distance from the Sun of &gt;3
  astronomical units is predominantly from the neck, where jets have been
  seen consistently. The nucleus rotates about the principal axis of
  momentum. The surface morphology suggests that the removal of larger
  volumes of material, possibly via explosive release of subsurface
  pressure or via creation of overhangs by sublimation, may be a major
  mass loss process. The shape raises the question of whether the two
  lobes represent a contact binary formed 4.5 billion years ago, or a
  single body where a gap has evolved via mass loss.

---------------------------------------------------------
Title: Instant: An Innovative L5 Small Mission Concept for Coordinated
    Science with Solar Orbiter and Solar Probe Plus
Authors: Lavraud, B.; Liu, Y. D.; Harrison, R. A.; Liu, W.;
   Auchere, F.; Gan, W.; Lamy, P. L.; Xia, L.; Eastwood, J. P.;
   Wimmer-Schweingruber, R. F.; Zong, Q.; Rochus, P.; Maksimovic, M.;
   Temmer, M.; Escoubet, C. P.; Kilpua, E.; Rouillard, A. P.; Davies,
   J. A.; Vial, J. C.; Gopalswamy, N.; Bale, S. D.; Li, G.; Howard,
   T. A.; DeForest, C. E.
2014AGUFMSH21B4109L    Altcode:
  We will present both the science objectives and related instrumentation
  of a small solar and heliospheric mission concept, INSTANT:
  INvestigation of Solar-Terrestrial Activity aNd Transients. It will be
  submitted as an opportunity to the upcoming ESA-China S-class mission
  call later this year. This concept was conceived to allow innovative
  measurements and unprecedented, early determination of key properties
  of Earthbound CMEs from the L5 vantage point. Innovative measurements
  will include magnetic field determination in the corona thanks to
  Hanle measurement in Lyman-α and polarized heliospheric imaging
  for accurate determination of CME trajectories. With complementary
  in situ measurements, it will uniquely permit solar storm science,
  solar storm surveillance, and synergy with Solar Orbiter and Solar
  Probe Plus (the ESA-China S2 mission launch is planned in 2021).

---------------------------------------------------------
Title: Multi-Resolution Stereophotoclinometry by Deformation, a New
    3D Shape Reconstruction Method Applied to ROSETTA/OSIRIS Images
Authors: Capanna, C.; Jorda, L.; Gesquière, G.; Gaskell, R. W.;
   Groussin, O.; Gutiérrez, P.; Hviid, S. F.; Lamy, P. L.; Preusker,
   F.; Rodionov, S.; Scholten, F.; Vibert, D.
2014AGUFM.P41C3941C    Altcode:
  We developed a new 3D shape reconstruction method which combines stereo,
  photoclinometry and the deformation of a triangular mesh describing
  the surface of the object. The method deforms the mesh - initially
  a sphere - until the set of synthetic images, created from the mesh
  (Jorda et al., SPIE 2010) match the observed one. Stereo control points
  can be used as a constraint in the deformation of the mesh, but it is
  not required at low resolutions.This new technique has been applied
  to images of the nucleus of comet 67P/Churyumov-Gerasimenko acquired
  by the OSIRIS instrument aboard the Rosetta spacecraft. The technique
  allowed to reconstruct the shape of the nucleus and to retrieve its
  rotational parameters from low-resolution images obtained with the
  narrow-angle camera of OSIRIS in mid-July 2014, when stereo-based
  techniques were still inapplicable. This model called "SHAP1" has
  been delivered to ESA and to the lander team in July. The technique
  has also been applied to higher-resolution images of the nucleus later
  on, using the stereo information as a constraint. A comparison of the
  reconstructed global and local models with those retrieved with other
  techniques, such as stereophotoclinometry (Gaskell et al., MPS 2008)
  and stereophotogrammetry (Preusker et al., PSS 2012) will be presented.

---------------------------------------------------------
Title: GIADA On-Board Rosetta: Early Dust Grain Detections and Dust
    Coma Characterization of Comet 67P/C-G
Authors: Rotundi, A.; Della Corte, V.; Accolla, M.; Ferrari, M.;
   Ivanovski, S.; Lucarelli, F.; Mazzotta Epifani, E.; Sordini, R.;
   Palumbo, P.; Colangeli, L.; Lopez-Moreno, J. J.; Rodriguez, J.;
   Fulle, M.; Bussoletti, E.; Crifo, J. F.; Esposito, F.; Green, S.;
   Grün, E.; Lamy, P. L.; McDonnell, T.; Mennella, V.; Molina, A.;
   Moreno, F.; Ortiz, J. L.; Palomba, E.; Perrin, J. M.; Rodrigo, R.;
   Weissman, P. R.; Zakharov, V.; Zarnecki, J.
2014AGUFM.P32B..05R    Altcode:
  GIADA (Grain Impact Analyzer and Dust Accumulator) flying on-board
  Rosetta is devoted to study the cometary dust environment of
  67P/Churiumov-Gerasimenko. GIADA is composed of 3 sub-systems:
  the GDS (Grain Detection System), based on grain detection through
  light scattering; an IS (Impact Sensor), giving momentum measurement
  detecting the impact on a sensed plate connected with 5 piezoelectric
  sensors; the MBS (MicroBalances System), constituted of 5 Quartz
  Crystal Microbalances (QCMs), giving cumulative deposited dust mass by
  measuring the variations of the sensors' frequency. The combination
  of the measurements performed by these 3 subsystems provides: the
  number, the mass, the momentum and the velocity distribution of
  dust grains emitted from the cometary nucleus.No prior in situ dust
  dynamical measurements at these close distances from the nucleus and
  starting from such large heliocentric distances are available up to
  date. We present here the first results obtained from the beginning
  of the Rosetta scientific phase. We will report dust grains early
  detection at about 800 km from the nucleus in August 2014 and the
  following measurements that allowed us characterizing the 67P/C-G
  dust environment at distances less than 100 km from the nucleus and
  single grains dynamical properties. Acknowledgements. GIADA was
  built by a consortium led by the Univ. Napoli "Parthenope" &amp;
  INAF-Oss. Astr. Capodimonte, IT, in collaboration with the Inst. de
  Astrofisica de Andalucia, ES, Selex-ES s.p.a. and SENER. GIADA is
  presently managed &amp; operated by Ist. di Astrofisica e Planetologia
  Spaziali-INAF, IT. GIADA was funded and managed by the Agenzia Spaziale
  Italiana, IT, with a support of the Spanish Ministry of Education and
  Science MEC, ES. GIADA was developped from a PI proposal supported by
  the University of Kent; sci. &amp; tech. contribution given by CISAS,
  IT, Lab. d'Astr. Spat., FR, and Institutions from UK, IT, FR, DE and
  USA. We thank the RSGS/ESAC, RMOC/ESOC &amp; Rosetta Project/ESTEC for
  their outstanding work. Science support provided by NASA through the US
  Rosetta Project managed by JPL/California Institute of Technology. GIADA
  calibrated data will be available through the ESA's PSA web site
  (www.rssd.esa.int/index.php?project=PSA&amp;page=index). Thanks
  Angioletta.

---------------------------------------------------------
Title: The photosphere-corona Interface: enrichement of the corona
    in low FIP elements and helium shells
Authors: Bazin, C.; Koutchmy, S.; Lamy, P.; Veselovski, I.
2014sf2a.conf..209B    Altcode:
  Slitless consecutive spectra were obtained during the contacts of
  the last total solar eclipses (2008, 2009, 2010, 2012, et 2013). They
  allowed to show that the overabundance of low First Ionisation Potential
  (FIP) elements (Fe II, Ti II, Ba II) in the corona comes from the low
  layers of the solar atmosphere, just near and above the temperature
  minimum region of the high photosphere. All spectra are recorded
  with a fast CCD/CMOS camera, with an equivalent radial resolution of
  60 milliarcseconds, or 45 km in the solar atmosphere, above a solar
  edge not affected by the parasitic light like it is outside of total
  eclipse conditions. Many emission lines of low FIP elements appear in
  regions situated between 200 to 600 km above the solar limb defined by
  the true continuum measured between the lines. This continuum appears
  at these altitudes where the beta of the plasma is near 1. The He I
  4713 Å and He II 4686 Å (Paschen alpha line) shells appear at the
  height of 800 km above the solar edge and higher. The light curve I =
  f(h) of each ion is located at a particuliar altitude in the solar
  atmosphere. The scale height corresponds to a density variation, which
  allows to evaluate the temperature thanks to the hydrostatic equilibrium
  assumption. Moreover, with ionised Titanium lines taken as markers,
  we show a similarity between the photosphere-corona interface and
  the prominence-corona interface. We discuss the role of the magnetic
  field and the ambipolar diffusion for supplying the corona in mass,
  without taking into account the role of spicules. The photo-ionisation
  of the helium lines by the EUV coronal lines is illustrated thanks to
  an extract of SDO/AIA coronal stacked image simultaneously obtained.

---------------------------------------------------------
Title: Overview of the Geomorphology of the Nucleus of Comet
    67P/Churyumov-Gerasimenko from OSIRIS Observations
Authors: Groussin, O.; Thomas, N.; Sierks, H.; Barbieri, C.; Lamy,
   P. L.; Rickman, H.; Rodrigo, R.; Koschny, D.
2014AGUFM.P33F..01G    Altcode:
  Because of the very peculiar conditions at the surface of cometary
  nuclei with very low gravity, outgassing, presence of ices and dust,
  their geomorphology is particularly complex. The presence of hummocky
  terrains (e.g., pits, hills, ridges, ...) and smooth terrains (e.g.,
  mesas, …) and their spatial distribution over the surface contain
  very valuable information to understand how comets work and to which
  extend they may still contain pristine materials on or close to their
  surface. Since July 2014, the Rosetta spacecraft has taken numerous
  high spatial resolution images (meter scale) of the surface of the
  nucleus of comet 67P/Churyumov-Gerasimenko with the OSIRIS cameras NAC
  (Narrow Angle Camera) and WAC (Wide Angle Camera). In this paper, we
  will present an overview of the geomorphologic features observed on
  this comet nucleus, including the cartography of the main features,
  and try to propose a scenario for the chronology of their formation
  and evolution.

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Title: Experimental study of an uncooled microbolometer array for
    thermal mapping and spectroscopy of asteroids
Authors: Brageot, E.; Groussin, O.; Lamy, P.; Reynaud, J. -L.
2014ExA....38..381B    Altcode:
  We report on the experimental study of the imaging and spectroscopic
  capabilities of an uncooled microbolometer array for space missions
  to small bodies in the inner solar system. The selected Nano640E <SUP>
  T M </SUP> device manufactured by the ULIS company (Grenoble, France)
  has a format of 640x480 pixels and can measure temperatures down to
  at least 255 K, the lower limit reached in our tests. It has a Noise
  Equivalent Temperature Difference (NETD) of 40.9 ±4.5 mK (300 K,
  F/0.86) and the capability to produce excellent, radiometrically
  calibrated images with an error of the order of 1 to 5 K depending
  upon the number of calibration sources. Using a set of neutral density
  filters, we determined the signal-to-noise ratio (SNR) of a spectrum
  acquired by the detector, as a function of the scene temperature,
  wavelength and spectral resolution. Considering an asteroid at 1 AU
  from the Sun, an optical system at F/0.86, a spectral resolution of
  0.3 μm and a scene temperature of &gt;350 K, the resulting spectrum
  has sufficient SNR to properly identify the main mineralogical emission
  features. Our results show that uncooled microbolometer arrays are very
  promising to acquire calibrated thermal images and mid-infrared (8-14
  μm) spectra of the surface of small bodies in the inner solar system.

---------------------------------------------------------
Title: The Geomorphology of Comet Churymov-Gerasimenko As Revealed
By Rosetta/Osiris: Implicationsfor Past Collisional Evolution
Authors: Marchi, S.; A'Hearn, M. F.; Barbieri, C.; Barucci, M. A.;
   Besse, S.; Cremonese, G.; Ip, W. H.; Keller, H. U.; Koschny, D.; Kuhrt,
   E.; Lamy, P. L.; Marzari, F.; Massironi, M.; Pajola, M.; Rickman,
   H.; Rodrigo, R.; Sierks, H.; Snodgrass, C.; Thomas, N.; Vincent, J. B.
2014AGUFM.P41C3940M    Altcode:
  In this paper we present the major geomorphological features of comet
  Churymov-Gerasimenko (C-G), with emphasis on those that may have formed
  through collisional processes. The C-G nucleus has been imaged with
  the Rosetta/OSIRIS camera system at varying spatial resolution. At
  the moment of this writing the maximum spatial resolution achieved is
  ~20 meter per pixel, and it will improve to reach the unprecedented
  centimeter-scale in November 2014. This resolution should allow us to
  identify and characterize pits, lineaments and blocks that could be
  the result of collisional evolution. Indeed, C-G has spent some 1000
  years on orbits crossing the main asteroid belt, and a much longer time
  in the outer solar system. Collisions may have, therefore, shaped the
  morphology of the nucleus in various ways. Previously imaged Jupiter
  Family Comets (e.g., Tempel 1) show significant numbers of pits and
  lineaments, some of which could be due to collisions. Additional
  proposed formation mechanisms are related to cometary activity
  processes, such as volatile outgassing.In addition to small scale
  features, the overall shape of C-G could also provide insights into
  the role of collisional processes. A striking feature is that C-G's
  shape is that of a contact binary. Similar shapes have been observed
  on rocky asteroids (e.g., Itokawa) and are generally interpreted as
  an indication of their rubble pile nature. A possibility is that C-G
  underwent similar processes, and therefore it may be constituted by
  reaccumulated fragments ejected from a larger precursor. An alternative
  view is that the current shape is the result of inhomogeneous outgassing
  activity, which may have dug a ~1-km deep trench responsible for
  the apparent contact binary shape.The role of the various proposed
  formation mechanisms (collisional vs outgassing) for both small scale
  and global features will be investigated and their implications for
  the evolution of C-G will be discussed.

---------------------------------------------------------
Title: The Nucleus of Comet 67P/Churyumov-Gerasimenko : a New Case
    of Contact Binary ?
Authors: Lamy, P. L.; A'Hearn, M. F.; Groussin, O.; Jorda, L.; Keller,
   H. U.; Rickman, H.
2014AGUFM.P41C3937L    Altcode:
  The nucleus of comet 67P/Churyumov-Gerasimenko appears to be formed of
  two components as revealed by images obtained with the OSIRIS narrow
  angle camera and the derived 3-D shape model (Jorda et al. 2014). This
  shape raises questions far beyond the obvious differences with the
  nuclei visited so far. We will explore the possible scenarios that
  may explain it. Whereas contact- binaries have been advocated for
  elongated nuclei (e.g., 19P/Borrelly and 103P/Hartley 2), the only
  unquestionable case remains that of 8P/Tuttle based on radar imaging
  (Harmon at al. 2010) and indirectly confirmed by HST observations
  (Lamy et al. 2008). However 8P originates from the Oort cloud where
  the collisional activity is essentially non-existent. A contact-binary
  among the Jupiter family comets (JFC) such as 67P would have profound
  implications since it must be primordial and the comet must have
  survived a possible history of collisions in the Kuiper belt. The
  present cumulative distribution function of size of nuclei of JFC comets
  indeed suggests a collisionally-relaxed population. Asymmetric erosion
  of an initially larger more regular body or even of a pre-existing
  contact binary will be studied in the framework of the past dynamical
  evolution of 67P (e.g., Groussin et al. 2007). Although unlikely, the
  scenario of a re-accumulated body following a catastrophic collision
  will be considered. Forthcoming images at higher spatial resolution
  with OSIRIS on the orbiter and CIVA and the lander will hopefully help
  deciphering the origin of the nucleus of 67P and restricting the number
  of possible scenarios.

---------------------------------------------------------
Title: Geomorphology of Active Regions on Comet
    67P/Churyumov-Gerasimenko from Osiris Observations
Authors: Auger, A. T.; Groussin, O.; Jorda, L.; Bouley, S.; Lamy,
   P. L.; Cremonese, G.; Thomas, N.; Sierks, H.
2014AGUFM.P41C3936A    Altcode:
  The geomorphological study of active regions on comets provides valuable
  insights to understand how comets work and to which extend they may
  still contain pristine materials on or close to their surface. The
  Rosetta spacecraft is orbiting comet 67P/Churyumov-Gerasimenko since
  summer 2014 and offers a unique opportunity to address this science
  topic. The Narrow and Wide Angle Cameras of the OSIRIS imaging
  experiment have acquired numerous images of the nucleus surface,
  with a spatial resolution down to the meter scale. Here, we focus on
  the geomorphology of some specific, active, regions of the nucleus,
  releasing materials from their surface or from their upper layers. With
  the help of digital terrains models and GIS tools, we map these regions
  and report their size, area, shape, slopes and surface roughness. This
  detailed analysis give us a reference point to emphasize their evolution
  as the comet approaches perihelion, but also provide information on
  the possibly pristine nature of these morphologies.

---------------------------------------------------------
Title: Comet 67P/Churyumov-Gerasimenko - First Science Results by
    Rosetta/OSIRIS
Authors: Sierks, H.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny,
   D.; Rickman, H.; Agarwal, J.; A'Hearn, M. F.; Angrilli, F.; Barucci,
   M. A.; Bertaux, J. L.; Bertini, I.; Besse, S.; Bodewits, D.; Capanna,
   C.; Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco,
   M.; Ferri, F.; Fornasier, S.; Fulle, M.; Gaskell, R. W.; Groussin,
   O.; Güttler, C.; Gutiérrez, P.; Hviid, S. F.; Ip, W. H.; Jorda,
   L.; Keller, H. U.; Joerg, K.; Kramm, R.; Kuhrt, E.; Küppers, M.; La
   Forgia, F.; Lara, L.; Lazzarin, M.; Leyrat, C.; Moreno, J. F.; Lowry,
   S.; Magrin, S.; Marchi, S.; Marzari, F.; Michalik, H.; Mottola, S.;
   Account, T.; Oklay, N.; Pajola, M.
2014AGUFM.P32B..02S    Altcode:
  Abstract ESA's Rosetta mission arrived on August 6, 2014, at target
  comet 67P/Churyumov-Gerasimenko after 10 years of cruise. OSIRIS
  (Optical, Spectroscopic, and Infrared Remote Imaging System) is the
  scientific imaging system onboard Rosetta. It comprises a Narrow
  Angle Camera (NAC) for nucleus surface and dust studies and a Wide
  Angle Camera (WAC) for the wide field coma investigations. We present
  the first science results achieved by OSIRIS from the arrival at the
  comet throughout the mapping phase. The overview will cover surface
  morphology and activity of the nucleus as seen in gas, dust, and
  local jets. Acknowledgements OSIRIS was built by a consortium led
  by the Max-Planck-Institut für Sonnensystemforschung, Göttingen,
  Germany, in collaboration with CISAS, University of Padova, Italy,
  the Laboratoire d'Astrophysique de Marseille, France, the Instituto de
  Astrofísica de Andalucia, CSIC, Granada, Spain, the Scientific Support
  Office of the European Space Agency, Noordwijk, The Netherlands,
  the Instituto Nacional de Técnica Aeroespacial, Madrid, Spain,
  the Universidad Politéchnica de Madrid, Spain, the Department of
  Physics and Astronomy of Uppsala University, Sweden, and the Institut
  für Datentechnik und Kommunikationsnetze der Technischen Universität
  Braunschweig, Germany. The support of the national funding agencies of
  Germany (DLR), France (CNES), Italy (ASI), Spain (MEC), Sweden (SNSB),
  and the ESA Technical Directorate is gratefully acknowledged. We
  thank the Rosetta Science Ground Segment at ESAC, the Rosetta Mission
  Operations Centre at ESOC and the Rosetta Project at ESTEC for their
  outstanding work enabling the science return of the Rosetta Mission.

---------------------------------------------------------
Title: Albedo and color variegations on 67/P Churyumov-Gerasimenko
    as observed by OSIRIS/Rosetta
Authors: Leyrat, Cedric; Barucci, Maria Antonietta; Fornasier, Sonia;
   Sierks, Holger; Hasselmann, Pedro; Besse, Sebastien; Oklay, Nilda;
   Jorda, Laurent; Barbieri, Cesare; Lamy, Philippe; Koschny, Detlef;
   Magrin, Sara; Bertini, Ivano; La Forgia, Fiorangela; A'Hearn, Michael;
   Bertaux, Jean Loup; Davidsson, Bjorn; Fulle, Marco; Groussin, Olivier;
   Gutierrez, Pablo; Hviid, Stubbe; Keller, Horst Uwe; Kueppers, Michael;
   Lazzarin, Monica; Kuehrt, Ekkehard; Lara, Luisa; Thomas, Nicolas;
   Vincent, Jean-Baptiste; Pajola, Maurizio
2014DPS....4610002L    Altcode:
  The ESA Rosetta spacecraft is in orbit around its target 67/P
  Churyumov-Gerasimenko since August 6th 2014. The OSIRIS camera system
  composed of the NAC (Narrow angle camera) and the WAC (Wide angle
  Camera) has the capability to image both the nucleus and the coma
  at different wavelengths from 0.245 microns up to 1 micron using
  filters. First images acquired from 100km distance have already
  revealed a very complex shape and potential areas with photometric
  variations. From August 2014 to the Philae landing event in November
  2014, the nucleus surface will be mapped at multiple resolutions (1m up
  to 20 cm), helping in the landing site selection process. Such images
  will be obtained at very different incidence, emission and phase angles,
  allowing us to correct from topographical features the photometric
  properties of the surface. This presentation will focus on the albedo
  and colors variations, and on the spectral slopes derived from the
  OSIRIS filters. Of particular interest will be the identification
  of ices on the surface, and the mineralogical differences between
  different areas characterized by different topographic features.

---------------------------------------------------------
Title: Comet 67P/Churyumov-Gerasimenko: First science results by
    Rosetta/OSIRIS
Authors: Thomas, Nicolas; Sierks, Holger; Barbieri, Cesare; Lamy,
   Philippe; Rodrigo, Rafael; Koschny, Detlef; Rickman, Hans; Agarwal,
   Jessica; A'Hearn, Michael; Angrilli, Francesco; Barucci, Antonella;
   Bertaux, Jean-Loup; Bertini, Ivano; Besse, Sebastien; Bodewits, Dennis;
   Capanna, Claire; Cremonese, Gabriele; Da Deppo, Vania; Davidsson,
   Björn; Debei, Stefano; De Cecco, Mariolino; Ferri, Francesca;
   Fornasier, Sonia; Fulle, Marco; Gaskell, Robert; Groussin, Olivier;
   Güttler, Carsten; Gutierrez, Pedroj; Hviid, Stubbe; Ip, Wing-Huen;
   Jorda, Laurent; Keller, Horst Uwe; Knollenberg, Jörg; Kramm, Rainer;
   Kührt, Ekkehard; Küppers, Michael; LaForgia, Fiorangela; Lara,
   Luisa; Lazzarin, Monica; Leyrat, Cedric; Lopez Moreno, Jose Juan;
   Lowry, Stephen; Magrin, Sara; Marchi, Simone; Marzari, Francesco;
   Michalik, Harald; Mottola, Stefano; Naletto, Giampiero; Oklay, Nilda;
   Pajola, Maurizio; Sabau, Lola; Snodgrass, Colin; Tubiana, Cecilia;
   Vincent, Jean-Baptiste; Wenzel, Peter
2014DPS....4610001T    Altcode:
  ESA’s Rosetta mission arrived on August 6, 2014, at target comet
  67P/Churyumov-Gerasimenko after 10 years of cruise. OSIRIS (Optical,
  Spectroscopic, and Infrared Remote Imaging System) is the scientific
  imaging system onboard Rosetta. It comprises a Narrow Angle Camera (NAC)
  for nucleus surface and dust studies and a Wide Angle Camera (WAC) for
  the wide field coma investigations.We present the first science results
  achieved by OSIRIS from the arrival at the comet throughout the mapping
  phase. The overview will cover surface morphology and activity of the
  nucleus as seen in gas, dust, and local jets.AcknowledgementsOSIRIS
  was built by a consortium led by the Max-Planck-Institut für
  Sonnensystemforschung, Göttingen, Germany, in collaboration with
  CISAS, University of Padova, Italy, the Laboratoire d'Astrophysique de
  Marseille, France, the Instituto de Astrofísica de Andalucia, CSIC,
  Granada, Spain, the Scientific Support Office of the European Space
  Agency, Noordwijk, The Netherlands, the Instituto Nacional de Técnica
  Aeroespacial, Madrid, Spain, the Universidad Politéchnica de Madrid,
  Spain, the Department of Physics and Astronomy of Uppsala University,
  Sweden, and the Institut für Datentechnik und Kommunikationsnetze
  der Technischen Universität Braunschweig, Germany. The support of
  the national funding agencies of Germany (DLR), France (CNES), Italy
  (ASI), Spain (MEC), Sweden (SNSB), and the ESA Technical Directorate
  is gratefully acknowledged. We thank the Rosetta Science Ground Segment
  at ESAC, the Rosetta Mission Operations Centre at ESOC and the Rosetta
  Project at ESTEC for their outstanding work enabling the science return
  of the Rosetta Mission.

---------------------------------------------------------
Title: Hubble Space Telescope Observations of the Nucleus of Comet
    C/2012 S1 (ISON)
Authors: Lamy, Philippe L.; Toth, Imre; Weaver, Harold A.
2014ApJ...794L...9L    Altcode:
  We report on the analysis of several sequences of broadband visible
  images of comet C/2012 S1 (ISON) taken with the Wide Field Camera 3
  of the Hubble Space Telescope on 2013 April 10, May 8, October 9, and
  November 1 in an attempt to detect and characterize its nucleus. Whereas
  the overwhelming coma precluded the detection of the nucleus in the
  first two sequences, the contrast was sufficient in early October to
  unambiguously retrieve the signal from the nucleus. Two images taken
  within a few minutes led to similar V magnitudes for the nucleus of
  21.97 and 22.0 with a 1σ uncertainty of 0.065. Assuming a standard
  value for the geometric albedo (0.04) and a linear phase function with
  a coefficient of 0.04 mag deg<SUP>-1</SUP>, these V values imply that
  the nucleus radius is 0.68 ± 0.02 km. Although this result does depend
  on these two assumptions, we argue that the radius most likely lies in
  the range 0.6-0.9 km. This result is consistent with the constraints
  derived from the water production rates reported by Combi et al. The
  last sequence of images in 2013 November revealed temporal variation
  of the innermost coma. If attributed to a single rotating jet, this
  coma brightness variation suggests the rotational period of the nucleus
  may be close to ~10.4 hr.

---------------------------------------------------------
Title: The rotation state of 67P/Churyumov-Gerasimenko from approach
    observations with the OSIRIS cameras on Rosetta
Authors: Mottola, S.; Lowry, S.; Snodgrass, C.; Lamy, P. L.; Toth,
   I.; Rożek, A.; Sierks, H.; A'Hearn, M. F.; Angrilli, F.; Barbieri,
   C.; Barucci, M. A.; Bertaux, J. -L.; Cremonese, G.; Da Deppo,
   V.; Davidsson, B.; De Cecco, M.; Debei, S.; Fornasier, S.; Fulle,
   M.; Groussin, O.; Gutiérrez, P.; Hviid, S. F.; Ip, W.; Jorda, L.;
   Keller, H. U.; Knollenberg, J.; Koschny, D.; Kramm, R.; Kührt, E.;
   Küppers, M.; Lara, L.; Lazzarin, M.; Lopez Moreno, J. J.; Marzari,
   F.; Michalik, H.; Naletto, G.; Rickman, H.; Rodrigo, R.; Sabau, L.;
   Thomas, N.; Wenzel, K. -P.; Agarwal, J.; Bertini, I.; Ferri, F.;
   Güttler, C.; Magrin, S.; Oklay, N.; Tubiana, C.; Vincent, J. -B.
2014A&A...569L...2M    Altcode:
  <BR /> Aims: Approach observations with the Optical, Spectroscopic,
  and Infrared Remote Imaging System (OSIRIS) experiment onboard
  Rosetta are used to determine the rotation period, the direction of
  the spin axis, and the state of rotation of comet 67P's nucleus. <BR
  /> Methods: Photometric time series of 67P have been acquired by
  OSIRIS since the post wake-up commissioning of the payload in March
  2014. Fourier analysis and convex shape inversion methods have been
  applied to the Rosetta data as well to the available ground-based
  observations. <BR /> Results: Evidence is found that the rotation rate
  of 67P has significantly changed near the time of its 2009 perihelion
  passage, probably due to sublimation-induced torque. We find that
  the sidereal rotation periods P<SUB>1</SUB> = 12.76129 ± 0.00005 h
  and P<SUB>2</SUB> = 12.4043 ± 0.0007 h for the apparitions before
  and after the 2009 perihelion, respectively, provide the best fit to
  the observations. No signs of multiple periodicity are found in the
  light curves down to the noise level, which implies that the comet
  is presently in a simple rotation state around its axis of largest
  moment of inertia. We derive a prograde rotation model with spin
  vector J2000 ecliptic coordinates λ = 65° ± 15°, β = + 59°
  ± 15°, corresponding to equatorial coordinates RA = 22°, Dec = +
  76°. However, we find that the mirror solution, also prograde, at λ
  = 275° ± 15°, β = + 50° ± 15° (or RA = 274°, Dec = + 27°),
  is also possible at the same confidence level, due to the intrinsic
  ambiguity of the photometric problem for observations performed close to
  the ecliptic plane. <P />Table 1 is available in electronic form at <A
  href="http://www.aanda.org/10.1051/0004-6361/201424590/olm">http://www.aanda.org</A>

---------------------------------------------------------
Title: Time dependent tomographic reconstruction of the solar corona
Authors: Peillon, C.; Vibert, D.; Frazin, R.; de Patoul, J.; Lamy, P.
2014ssip.confP...1P    Altcode: 2014ssip.confP...1C
  The distribution of the electron density in the corona is crucial to
  advance the knowledge in understanding the nature of solar coronal
  phenomena. Several methods for the reconstruction of 3D density of
  the solar corona from projection data have been proposed. One of
  the major difficulties is the problem of the restrictive assumption
  that the structure of the corona does not vary with time. The solar
  temporal evolution introduces a lot of errors in classic tomographic
  reconstruction. In this poster we present a new time dependent
  tomography method by adding a spatial, temporal and rotational
  regularization matrices. We perform the method on images from a 3D MHD
  model of the corona during a period of 14 days in November 2008. We
  compute the normalized error between the model and the reconstruction
  in order to estimate the quality of the reconstruction. We also perform
  the developed tomography methods on polarized brightness images of
  the SOHO/LASCO instrument. We show that the new time dependent method
  decrease the number of artefacts by comparing our results with classic
  static tomographic reconstruction. In particular, we show that the
  spatial and temporal regularization matrices improves significantly
  the reconstruction and that the rotational regularization is useful
  when using a large amount of images during the 14 days period.

---------------------------------------------------------
Title: Constraints on the subsurface structure and density of
    the nucleus of Comet 67P/Churyumov-Gerasimenko from Arecibo radar
    observations
Authors: Kamoun, P.; Lamy, P. L.; Toth, I.; Herique, A.
2014A&A...568A..21K    Altcode:
  Context. Little is known about the internal structure of cometary
  nuclei. In addition to understanding their accretion in the early
  solar nebula and their subsequent evolution in the solar system,
  we find this question to be of acute and timely interest in the case
  of 67P/Churyumov-Gerasimenko (hereafter 67P/C-G) due to be visited
  by the Rosetta spacecraft in the second half of 2014. In particular,
  the successful landing of the Philae surface module depends critically
  upon the bulk density of the nucleus and the structure of its surface
  layer. <BR /> Aims: In addition to fostering our general knowledge of
  these properties, it is important to exploit all possible information
  to assist in preparing the delivery of Philae. <BR /> Methods: We
  performed an in-depth analysis of the observations done with the
  radar system of the Arecibo Observatory in November 1982 when comet
  67P/C-G had a close encounter with Earth at a geocentric distance of
  0.4AU taking our present knowledge of the properties of its nucleus
  (size, rotational state) into account. <BR /> Results: In the absence
  of a detectable radar echo, we determined a maximum radar cross
  section of 0.7 km<SUP>2</SUP>, leading to a maximum radar albedo of
  0.05. This low albedo probably results from a combination of a low
  radar reflectivity material and a lightly packed upper layer of the
  nucleus with substantial roughness (rms slope of ≈55°), consistent
  with its low thermal inertia. Based on radar observations of other
  cometary nuclei and asteroids, it is unlikely that the albedo can
  be lower than 0.04 so that we were able to constrain the dielectric
  permittivity of the subsurface layer to a narrow range of 1.9 to
  2.1. Laboratory measurements and our modeling of mixtures of ice and
  dust have led to a porosity in the range of approximately 55 to 65%
  and a density in the range of ≈600 to ≈1000 kg m<SUP>-3</SUP>
  for the top ≈2.5 m layer of the nucleus. This would be the bulk
  density range for a homogeneous nucleus and would place the success
  of the landing at risk, but an inhomogeneous nucleus with an overall
  density below this range remains a possibility.

---------------------------------------------------------
Title: Similar origin for low- and high-albedo Jovian Trojans and
    Hilda asteroids?
Authors: Marsset, M.; Vernazza, P.; Gourgeot, F.; Dumas, C.; Birlan,
   M.; Lamy, P.; Binzel, R. P.
2014A&A...568L...7M    Altcode: 2014arXiv1407.7016M
  Hilda asteroids and Jupiter Trojans are two low-albedo (p<SUB>v</SUB>
  ~ 0.07) populations for which the Nice model predicts an origin in
  the primordial Kuiper Belt region. However, recent surveys by WISE
  and the Spitzer Space Telescope (SST) have revealed that ~2% of these
  objects possess high albedos (p<SUB>v</SUB> ≥ 0.15), which might
  indicate interlopers - that is, objects not formed in the Kuiper
  Belt - among these two populations. Here, we report spectroscopic
  observations in the visible and / or near-infrared spectral ranges of
  twelve high-albedo (p<SUB>v</SUB> &gt; 0.15) Hilda asteroids and Jupiter
  Trojans. These twelve objects have spectral properties similar to those
  of the low-albedo population, which suggests a similar composition and
  hence a similar origin for low- and high-albedo Hilda asteroids and
  Jupiter Trojans. We therefore propose that most high albedos probably
  result from statistical bias or uncertainties that affect the WISE
  and SST measurements. However, some of the high albedos may be true
  and the outcome of some collision-induced resurfacing by a brighter
  material that could include water ice. Future work should attempt
  to investigate the nature of this supposedly bright material. The
  lack of interlopers in our sample allows us to set an upper limit of
  0.4% at a confidence level of 99.7% on the abundance of interlopers
  with unexpected taxonomic classes (e.g., A-, S-, V-type asteroids)
  among these two populations. <P />Reflectance spectra presented
  in this paper are available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/568/L7">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/568/L7</A>Based
  on observations collected at the European Organisation for Astronomical
  Research in the Southern Hemisphere, Chile (ESO program ID: 091.C-0247).

---------------------------------------------------------
Title: Constraints on the nucleus of comet C/2012 S1 (ISON) from
    the Hubble Space Telescope observations
Authors: Lamy, P.; Toth, I.; Li, J.; Weaver, H.
2014acm..conf..304L    Altcode:
  Comet C/2012 S1 (ISON) was both a dynamically new comet, visiting
  the inner solar system for the first time since being scattered
  and deeply frozen in the Oort Cloud, and a sungrazing comet. This
  unique combination made it an attractive target for the Hubble Space
  Telescope. It was observed on 10 April 2013 when the comet was 4.15 au
  from the Sun, 4.24 au from the Earth, and at a phase angle of 13.7°,
  henceforth well before C/ISON crossed the ”snow line” (2.5--3
  au), avoiding strong activity driven by water-ice sublimation and,
  thus, potentially increasing the chance of detecting its nucleus. The
  observations were performed over three separate orbits spanning a time
  interval of 18 hours using the Wide Field Camera 3 (WFC3) UVIS detector
  to image C/ISON through two broadband filters, the ”wide-V” F606W and
  ”blue” F438W filters (Li at al. 2013). The twelve images obtained
  with the F606W filter were analyzed using our well-proven technique
  of fitting a parametric model of the expected surface brightness to
  the observed images (e.g., Lamy et al. 2006). The model consists of
  an unresolved point source and a coma specified by a power law, both
  convolved with the point spread function of the telescope. The nucleus
  is basically undetected, which imposes an upper limit of its radius
  of ∼0.3 km. However, the analysis is complicated by the so-called
  ”breathing” of the WFC3 camera, an uncontrolled slight defocus
  which distorts the PSF. We investigated this question in detail and
  considered various cases of defocus. We will report on this effort
  and the resulting robust upper limit which we can put on the size of
  the nucleus of C/ISON.

---------------------------------------------------------
Title: VizieR Online Data Catalog: Reflectance spectra of 12 Trojans
    and Hildas (Marsset+, 2014)
Authors: Marsset, M.; Vernazza, P.; Gourgeot, F.; Dumas, C.; Birlan,
   M.; Lamy, P.; Binzel, R. P.
2014yCat..35689007M    Altcode:
  We present 17 reflectance spectra of 12 high albedo
  (p<SUB>v</SUB>&gt;0.14) Trojans (8 objects) and Hildas (4 objects)
  obtained with the ESO/VLT Echelle spectrograph X-SHOOTER in
  the 0.3-2.2um spectral range (14 spectra) and with the NASA/IRTF
  spectrograph SpeX in the 0.8-2.5um spectral range (3 spectra). X-SHOOTER
  spectra were normalized to unity at 0.55um and SpeX spectra were
  normalized to unity at 2.2um . The spectra presented in this work were
  collected between April and December 2013. <P />(18 data files).

---------------------------------------------------------
Title: Early results on 67P/Churyumov-Gerasimenko observed by
    Rosetta/OSIRIS
Authors: Sierks, H.; Tubiana, C.; Snodgrass, C.; Agarwal, J.;
   Güttler, C.; Oklay, N.; Vincent, J.; Küppers, M.; Barbieri, C.;
   Lamy, P.; Rickman, H.; Rodrigo, R.; Koschny, D.; Hviid, S.; Mottola,
   S.; Osiris Team
2014acm..conf..495S    Altcode:
  67P/Churyumov-Gerasimenko (67P) is the target comet of the ESA
  Rosetta mission. Launched in 2004, the Rosetta spacecraft woke up on
  the 20th of January 2014. After 36 months of deep space hibernation,
  Rosetta is now traveling to rendezvous with the comet at 4.1 au from
  the Sun, and it will follow 67P along its orbit, investigating how the
  comet changes and evolves while approaching the Sun. <P />The Optical,
  Spectroscopic, and Infrared Remote Imaging System OSIRIS (Keller et al.,
  2007) is the scientific imaging system onboard Rosetta. It comprises
  the Narrow Angle Camera (NAC) with wavelength range 250--1000 nm and
  the Wide Angle Camera (WAC) with wavelength range 240--720 nm. The NAC
  (FOV = 2.20×2.22 deg) is a system with high spatial resolution that
  allows an initial detection of the nucleus, studies its structure and
  rotation from relatively great distances, investigates the mineralogy
  of the surface, and studies the dust ejection processes. The WAC has
  much lower spatial resolution but, accordingly, a much wider field
  of view (about 11.35×12.11 deg). This allows observations of the
  3-dimensional flow field of dust and gas near the nucleus and, in
  addition, provides a synoptic view of the whole nucleus. In summary,
  the WAC would provide long-term monitoring of the entire nucleus from
  close distances, while the NAC studies the details. The two camera
  units have been designed as a complementary pair, which, on one hand,
  addresses the study of the nucleus surface, and on the other hand,
  investigates the dynamics of the sublimation process. <P />After
  commissioning in March 2014, OSIRIS took first images of comet 67P and
  its dust environment. Ground-based observations performed in 2007/08
  when 67P was in the same orbital arc as it will be in March/April
  2014, show that the comet was already active at 4.3 au inbound and
  that its behavior was repetitive during the last three apparitions
  (Snodgrass et al. 2013). We therefore expect to detect early comet
  activity by OSIRIS in March/April 2014. At this time, Rosetta will
  be at about 4 million kilometers from the comet and 67P will still be
  unresolved. <P />We present results about the early cometary activity
  based on OSIRIS images. Orange-filter images (central wavelength 649.2
  nm) will be used to determine the dust environment of 67P, since this
  wavelength range is quite free from gas emission lines. <P />Moreover,
  a series of lightcurves will be taken to compare with the existing
  ones and look for possible changes in the rotational period due to
  its last perihelion passage.

---------------------------------------------------------
Title: Investigation of the interior of primordial asteroids and
the origin of the Earth's water: The INSIDER space mission
Authors: Vernazza, P.; Lamy, P.
2014acm..conf..559V    Altcode:
  Today's asteroid belt may not only be populated by objects that
  formed in situ, typically between 2.2 and 3.3 au, but also by bodies
  that formed over a very large range of heliocentric distances. It is
  currently proposed that both the early (&lt;5 Myrs after Solar System
  formation) and late (&gt;700 Myrs after Solar System formation)
  dynamical evolution of the Solar System was governed by giant
  planet migrations that led to the insertion of inner (1--3 au) as
  well as outer (4--13 au) small bodies in the asteroid belt. Taken
  altogether, the current dynamical models are able to explain many
  striking features of the asteroid belt including i) its incredible
  compositional diversity deduced mainly from spectroscopic observations
  and meteorites measurements, and ii) the evidence of radial mixing
  experienced by the various asteroid classes (e.g., S-, C-types) after
  their formation. In a broad stroke, the idea that the asteroid belt
  is a condensed version of the primordial Solar System is progressively
  emerging. The asteroid belt therefore presents the double advantage of
  being easily accessible and of offering crucial tests for the formation
  models of the Solar System by exploring the building blocks predicted
  by models of i) the telluric planets, ii) the giant planet cores,
  iii) the giant planets' satellites, and iv) outer small bodies such
  TNOs and comets. It also appears as an ideal place to search for the
  origin of Earth's water. <P />Up to now, only a few asteroid classes
  (e.g., several S-types) have been visited by spacecraft and the focus
  of these in situ measurements has been mainly to give a geological
  context to ground based observations as well as strengthen/validate
  their interpretation. Most of the tantalizing discoveries of asteroid
  missions have been realized via images of the objects surfaces. Time
  has come for asteroid space science to reach a new milestone by
  extending the reconnaissance of the Belt's diversity and addressing
  new science questions. <P />The scientific objectives of the INSIDER
  mission, to be proposed in response to the 2014 ESA call for an M-class
  mission, require the exploration of diverse primordial asteroids ---
  possibly the smallest surviving protoplanets of our Solar System ---
  in order to constrain the earliest stages of planetesimal formation
  thus avoiding the effect of destructive collisions, which produce
  extensively processed rubble piles. Our science objectives that
  justify in situ measurements in the context of an M-class mission
  and that are expected to lead to significant breakthroughs include:
  <P />- The exploration of the diversity of the asteroid belt <P />-
  The first investigation of the internal structure of asteroids <P
  />- The origin of water on Earth <P />The proposed mission scenario
  consists in i) successive rendez-vous followed by orbit insertion of
  two and possibly three large (D&gt;100 km) objects, ii) one or two small
  landing modules (MASCOT type) to perform cosmochemical measurements (D/H
  ratio, O isotopes). The potential targets would include 24 Themis and 10
  Hygiea. <P />Meeting our science objectives requires instruments (such
  as radar, seismometers to be dropped to the surface, magnetometer, high
  resolution laser-desorption-ionization mass spectrometer to analyse the
  surface samples) not flown so far during past asteroids missions along
  with the traditional powerhouses, such as cameras and spectrometers.

---------------------------------------------------------
Title: Preliminary solution for the shape and rotational state of
    the nucleus of comet 67P/Churyumov-Gerasimenko
Authors: Lamy, P.; Jorda, L.; Kaasalainen, M.; Hviid, S.; Faury, G.;
   Toth, I.; Groussin, O.
2014acm..conf..303L    Altcode:
  In preparation of ESA's ROSETTA mission to comet
  67P/Churyumov-Gerasimenko, solutions for the shape and rotational state
  of its nucleus have been published based on observation with the Hubble
  and Spitzer space telescopes as well as ground-based observations
  (Lamy et al. 2006, 2007, 2008; Lowry et al. 2012). Following the
  wake-up of the Rosetta spacecraft in January 2014 and the successful
  commissioning of the OSIRIS camera system in March, a first lightcurve
  of the inactive nucleus has been obtained on 23 March 2014 with the
  OSIRIS Narrow Angle Camera (NAC). Further lightcurves will be acquired
  in the forthcoming months. We will present an updated solution for the
  shape and rotational state based on these data sets as of end of June
  2014 combined with past Hubble and Spitzer space telescopes as well as
  ground-based observations using the technique of lightcurve inversion.

---------------------------------------------------------
Title: Constraints on the subsurface structure and density of the
    nucleus of Comet 67P/Churyumov-Gerasimenko from radar observations
Authors: Lamy, Philippe; Kamoun, Paul; Toth, Imre; Herique, Alain
2014EGUGA..16.6993L    Altcode:
  We performed an in-depth analysis of the observations carried with
  the radar system of the Arecibo Observatory in November 1982 when
  comet 67P/Churyumov-Gerasimenko had a close encounter with Earth
  at a geocentric distance of 0.4 AU taking into account our present
  knowledge of the properties of its nucleus (size, rotational state). In
  the absence of a detectable radar echo, we determined a maximum
  radar cross section of 0.7 km2 leading to a maximum radar albedo of
  0.05. This low albedo probably results from a combination of a low radar
  reflectivity material and a lightly packed upper layer of the nucleus
  with substantial roughness (rms slope of ≡55°), consistent with
  its low thermal inertia. Based on radar observations of other cometary
  nuclei and asteroids, it is unlikely that the albedo can be lower than
  0.04 so that we were able to constrain the dielectric permittivity
  of the subsurface layer to a narrow range of 1.9 to 2.1. Laboratory
  measurements and our modeling of mixtures of ice and dust led to a
  porosity in the range of approximately 55 to 65% and a density in the
  range of ≡600 to ≡1000 kg m-3 for the top ≡2.5 m layer of the
  nucleus. This would be the bulk density range for an homogeneous nucleus
  and would place the success of the landing at risk but an inhomogeneous
  nucleus with an overall density below this range remains a possibility.

---------------------------------------------------------
Title: Radiation forces on small particles in the Solar System:
    A re-consideration
Authors: Burns, Joseph A.; Lamy, Philippe L.; Soter, Steven
2014Icar..232..263B    Altcode:
  We respond to Klačka et al. (Klačka, J., Petržala,
  J., Pástor, P., Kómar, L. [2014]. Icarus, this issue,
  http://dx.doi.org/10.1016/j.icarus.2012.06.044.), who have criticized
  many previous derivations of the acceleration experienced by a
  spherical interplanetary particle owing to the Sun’s radiation. Much
  of their criticism arises from differences in semantics and
  notation as well as effects that are unimportant at Solar System
  speeds. Accordingly, in the appropriate limiting cases, most published
  expressions for the radiation forces, such as that found in Burns
  et al. (Burns, J.A., Lamy, P.L., Soter, S. [1979]. Icarus 40 1-48),
  are correct and duplicate the results of Klačka et al. (Klačka, J.,
  Petržala, J., Pástor, P., Kómar, L. [2014]. Icarus, this issue,
  http://dx.doi.org/10.1016/j.icarus.2012.06.044).

---------------------------------------------------------
Title: Low and high albedo jovian Trojans and Hildas: a similar or
    different origin?
Authors: Marsset, M.; Vernazza, P.; Gourgeot, F.; Dumas, C.; Birlan,
   M.; Lamy, P.; Binzel, R. P.
2014EPSC....9...54M    Altcode:
  Jupiter Trojans and Hilda asteroids are small primitive bodies
  located near or beyond the snow line, around respectively the L4 and
  L5 Lagrange points of Jupiter at ~5.2AU from the sun (Trojans) and in
  the 2:3 mean-motion resonance with Jupiter near 3.9AU (Hildas). Our
  current understanding of the early dynamical evolution of the Solar
  System tells us that they probably originated from the primordial
  transneptunian region from which they were captured in their current
  location (Nice model; [6, 5]). In addition, this region not only
  comprised planetesimals formed beyond the snow line (D-, T- and
  X-type asteroids) but also a minor population of rocky interlopers
  (e.g., A-, S-, V-type asteroids) that migrated outward during the
  very early evolutionary phases of the Solar System 5 to 7My after its
  formation (Grand Tack model; [8]). The recent discovery by WISE [2,
  3] and Spitzer [1] of high albedo (pv ≥0.15) asteroids within jovian
  Trojans and Hildas opened the possibility of an observational evidence
  for the presence of a small fraction (~2 %) of such interlopers among
  these two low albedo (pv ∼0.07) populations. Here, we report the
  very first spectroscopic characterization of a sample of high albedo
  tTrojans and Hildas obtained with X-SHOOTER and SpeX in the visible
  and / or nearinfrared ranges. This study allows us to investigate
  the origin of these high albedo objects and to provide an estimate
  of the contamination rate of jovian Trojans and Hilda asteroids by
  objects that do not belong to the C / T / D-type complex (e.g., A-,
  S-, V-type asteroids), thus constraining migration models [7, 4, 6,
  5, 8]. The results of this study will be presented in details.

---------------------------------------------------------
Title: The Interaction Between Coronal Mass Ejections and Streamers:
    A Statistical View over 15 Years (1996 - 2010)
Authors: Floyd, O.; Lamy, P.; Llebaria, A.
2014SoPh..289.1313F    Altcode:
  We report on the statistical analysis of the interaction between
  coronal mass ejections (CMEs) and streamers based on 15 years (from
  1996 to 2010 inclusive) of observation of the solar corona with the
  LASCO-C2 coronagraph. We used synoptic maps and improved the method
  of analysis of past investigations by implementing an automatic
  detection of both CMEs and streamers. We identified five categories of
  interaction based on photometric and geometric variations between the
  pre- and post-CME streamers: "brightening", "dimming", "emergence",
  "disappearance", and "deviation". A sixth category, "no change",
  included all cases where none of the above variations is observed. A
  "global set" of 21 242 CMEs was considered as well as a subset of the
  10 % brightest CMEs (denoted "top-ten") and three typical periods of
  solar activity: minimum, intermediate, and maximum. We found that about
  half of the global population of CMEs are not associated with streamers,
  whereas 93 % of the 10 % brightest CMEs are associated. When there is a
  CME-streamer association, approximately 95 % of the streamers experience
  a change, either geometric or radiometric. The "no change" category
  therefore amounts to approximately 5 %, but this percentage varies
  from 1 - 2 % during minimum to 7 - 8 % during intermediate periods of
  activity; values of 3 - 5 % are recorded during maximum. Emergences
  and disappearances of streamers are not dominant processes; they
  constitute 16 - 17 % of the global set and 23 % (emergence) and 28 %
  (disappearance) of the "top-ten" set. Streamer deviations are observed
  for 57 % and 70 % of, respectively, the global set and "top-ten"
  CMEs. The cases of dimming and brightening are roughly equally present
  and each case constitutes approximately 30 - 35 % of either set,
  global or "top-ten".

---------------------------------------------------------
Title: Automated Processing of LASCO Coronal Images: Spurious
    Point-Source-Filtering and Missing-Blocks Correction
Authors: Pagot, E.; Lamy, P.; Llebaria, A.; Boclet, B.
2014SoPh..289.1433P    Altcode:
  We report on automated procedures for correcting the images of the LASCO
  coronagraph for i) spurious quasi-point-sources such as the impacts
  of cosmic rays, stars, and planets, and ii) the absence of signal due
  to transmission errors or dropouts, which results in blocks of missing
  information in the images. Correcting for these undesirable artifacts
  is mandatory for all quantitative works on the solar corona that require
  data inversion and/or long series of images, for instance. The nonlinear
  filtering of spike noise or point-like objects is based on mathematical
  morphology and implements the procedure opening by morphological
  reconstruction. However, a simple opening filter is applied whenever
  the fractional area of corrupted pixels exceeds 50 % of the original
  image. We describe different strategies for reconstructing the missing
  information blocks. In general, it is possible to implement the method
  of averaged neighbors using the two images obtained immediately before
  and after the corrupted image. For the other cases, and in particular
  when missing blocks overlapped in three images, we developed an
  original procedure of weighted interpolation along radial profiles
  from the center of the Sun that intercept the missing block(s). This
  procedure is also adequate for the saturated images of bright planets
  (such as Venus) that bleed along the neighboring pixels. Missing
  blocks in polarized images may generally be reconstructed using the
  associated unpolarized image of the same format. But in the case of
  overlapping missing blocks, we implemented our procedure of weighted
  interpolation. All tests performed on numerous LASCO-C2 images at
  various periods of solar activity (i.e. varying complexity of the
  structure of the corona) demonstrate the excellent performance of
  these new procedures, with results vastly superior to the methods
  implemented so far in the pipeline-processing of the LASCO images.

---------------------------------------------------------
Title: Global and Spatially Resolved Photometric Properties of the
    Nucleus of Comet 67P/C-G from OSIRIS Images
Authors: Lamy, P.
2014EPSC....9..233L    Altcode:
  Following the successful wake-up of the ROSETTA spacecraft on 20
  January 2014, the OSIRIS imaging system was fully re-commissioned at the
  end of March 2014 confirming its initial excellent performances. The
  OSIRIS instrument includes two cameras: the Narrow Angle Camera (NAC)
  and the Wide Angle Camera (WAC) with respective fieldsofview of 2.2°
  and 12°, both equipped with 2K by 2K CCD detectors and dual filter
  wheels. The NAC filters allow a spectral coverage of 270 to 990 nm
  tailored to the investigation of the mineralogical composition of
  the nucleus of comet P/Churyumov- Gerasimenko whereas those of the
  WAC (245-632 nm) aim at characterizing its coma [1]. The NAC has
  already secured a set of four complete light curves of the nucleus
  of 67P/C-G between 3 March and 24 April 2014 with a primary purpose
  of characterizing its rotational state. A preliminary spin period of
  12.4 hours has been obtained, similar to its very first determination
  from a light curve obtained in 2003 with the Hubble space telescope
  [2]. The NAC and WAC will be recalibrated in the forthcoming weeks
  using the same stellar calibrators VEGA and the solar analog 16 Cyg B
  as for past inflight calibration campaigns in support of the flybys of
  asteroids Steins and Lutetia. This will allow comparing the pre- and
  post-hibernation performances of the cameras and correct the quantum
  efficiency response of the two CCD and the throughput for all channels
  (i.e., filters) if required. The accurate photometric analysis of the
  images requires utmost care due to several instrumental problems, the
  most severe and complex to handle being the presence of optical ghosts
  which result from multiple reflections on the two filters inserted
  in the optical beam and on the thick window which protects the CCD
  detector from cosmic ray impacts. These ghosts prominently appear as
  either slightly defocused images offset from the primary images or
  large round or elliptical halos. We will first present results on the
  global photometric properties of the nucleus of comet 67P/C-G, albedo,
  phase function and spectral reflectivity and compare with previous
  results obtained with the Hubble and Spitzer space telescopes [2, 3,
  4]. Then observations during the approach and first bound orbits in
  July-August 2014 will allow mapping the surface of the nucleus with
  OSIRIS at a scale of up to 1 meter per pixel. The images will be used
  to reconstruct the 3D surface of the nucleus at highresolution allowing
  separating true photometric variations from topographic effects. We
  will present results on the spatially resolved photometric properties
  of the nucleus based on a novel method developed in the space of the
  facets representing the three-dimensional shape of the body. This
  method successfully implemented in the cases of the nucleus of comet
  9P/Tempel 2 and of asteroid (2867) Steins [5] has the advantage of
  automatically tracking the same local surface element on a series of
  images. The analysis will then proceed with the determination of the
  global Hapke and other standard photometric parameters as well as their
  two-dimensional variations across the surface. This allows defining, in
  the body-fixed reference frame, “high residual regions” (HRRs) which
  correspond to significant relative differences between the observed
  and modeled photometric parameters such as the singlescattering albedo
  (SSA), the mean roughness slope angle, and the reflectivity gradient. Of
  particular interest will be the search for ice patches and possible
  mineralogical differences resulting from the past activity of the comet.

---------------------------------------------------------
Title: First close view at comet 67P/ Churyumov-Gerasimenko by
    Rosetta/OSIRIS
Authors: Sierks, H.; Barbieri, C.; Lamy, P.; Rickman, H.; Rodrigo, R.;
   Koschny, D.; Keller, H. U.; Jorda, L.; Fornasier, S.; Massironi, M.;
   Vincent, J. -B.; Snodgrass, C.; Tubiana, C.; Agarwal, J.; Güttler,
   C.; Oklay, N.
2014EPSC....9..518S    Altcode:
  ESA's Rosetta mission arrived at target comet 67P/Churyumov-Gerasimenko
  after 10 years of cruise. OSIRIS (Optical, Spectroscopic, and
  Infrared Remote Imaging System) is the scientific imaging system
  onboard Rosetta. It comprises a Narrow Angle Camera (NAC) for nucleus
  surface and dust studies and a Wide Angle Camera (WAC) for the wide
  field coma investigations. We present the first scientific results
  from comet detection, activity wake-up, to the high resolution images
  of surface and topographical features.

---------------------------------------------------------
Title: Global Shape and Topography of the Nucleus of Comet 67P/C-G
    from ROSETTA/OSIRIS Images
Authors: Jorda, L.; Gaskell, R.; Hviid, S.; Capanna, C.; Groussin,
   O.; Gutierrez, P.; Lamy, P.; Scholten, F.; Preusker, F.; Kaasalainen,
   M.; Keller, H. U.; Knollenberg, J.; Kührt, E.; Mottola, S.; Sierks,
   H.; Snodgrass, C.; Thomas, N.; Toth, I.; Vincent, J. -B.
2014EPSC....9..665J    Altcode:
  The ROSETTA spacecraft will approach the nucleus of comet
  P/Churyumov-Gerasimenko in early August 2014 after a successful wake-up
  on January 20, 2014. The OSIRIS instrument is a set of two cameras
  aboard ROSETTA: the Narrow Angle Camera and the Wide Angle Camera which
  have fields-of-view of 2.2° and about 12° respectively. Both cameras
  are equipped with a 2K by 2K CCD detector. The two cameras have been
  successfully re-commissioned at the end of March 2014. Observations
  during the approach and first bound orbits in July-August 2014 will
  allow to map the surface of the nucleus with OSIRIS at a scale as
  small as 1 m/pixel. The images will be used to reconstruct the 3D
  global topography of the nucleus at high-resolution with a combination
  of two advanced reconstruction techniques: stereophotogrammetry and
  stereophotoclinometry. The reconstructed global shape will be used
  to determine the bulk density of the nucleus with an accuracy of
  a few percent and to localize and quantitatively characterize the
  main topographic features at its surface. It will also allow us to
  identify the different types of terrains present at the surface of the
  nucleus. We will describe and discuss the bulk properties of the nucleus
  (bulk shape, density and moments of inertia) against those of other
  comets observed from the ground or by previous space probes. We will
  also identify the main topographic features from a combined analysis of
  images and global digital terrain models and compare them with those
  identified at the surface of comets P/Borrelly, P/Wild 2 and P/Tempel
  1 by previous space probes. Finally, we will propose a preliminary
  interpretation for the processes involved in their formation.

---------------------------------------------------------
Title: Early Grain Detections in the Coma of Comet
    67P/Churyumov-Gerasimenko
Authors: Rotundi, A.; Della Corte, V.; Fulle, M.; Accolla, M.;
   Ferrari, M.; Ivanovski, S.; Lucarelli, F.; Sordini, R.; Zakharov, V.;
   Mazzotta Epifani, E.; Lopez-Moreno, J. J.; Rodriguez, J.; Colangeli,
   L.; Palumbo, P.; Crifo, J. C.; Bussoletti, E.; Esposito, F.; Green, S.;
   Grün, E.; Lamy, P. L.; McDonnell, J. A. M.; Mennella, V.; Molina, A.;
   Morales, R.; Moreno, F.; Ortiz, J. L.; Palomba, E.; Perrin, J. -M.;
   Rietmeijer, F. J. M.; Rodrigo, R.; Weissman, P. R.; Zarnecki, J. C.;
   Cosi, M.; Giovane, F.; Gustafson, B.; Herranz, M. L.; Jeronimo, J. M.;
   Leese, M. R.; Lopez-Jimenez, A.; Altobelli, N.
2014EPSC....9..868R    Altcode:
  The GIADA (Grain Impact Analyser and Dust Accumulator) instrument aboard
  the Rosetta spacecraft at comet 67P/Churyumov-Gerasimenko (67P/C-G)
  measures dust grain number, mass, momentum and velocity [1,2]. GIADA
  is composed of three sub-systems: the Grain Detection System (GDS),
  detecting dust grains based on light scattering; an Impact Sensor
  (IS), providing momentum measurements from the impact on a plate
  connected to five piezoelectric sensors; and the MicroBalances System
  (MBS), made up of five Quartz Crystal Microbalances (QCMs), to yield
  cumulative deposited dust mass through the shift in resonance frequency.

---------------------------------------------------------
Title: Giada: its Status after the Rosetta Cruise Phase and
    On-Ground Activity in Support of the Encounter with Comet
    67P/CHURYUMOV-GERASIMENKO
Authors: Della Corte, V.; Rotundi, A.; Accolla, M.; Sordini, R.;
   Palumbo, P.; Colangeli, L.; Lopez–Moreno, J. J.; Rodriguez, J.;
   Rietmeijer, F. J. M.; Ferrari, M.; Lucarelli, F.; Mazzotta Epifani, E.;
   Ivanovski, S.; Aronica, A.; Cosi, M.; Bussoletti, E.; Crifo, J. F.;
   Esposito, F.; Fulle, M.; Green, S. F.; Gruen, E.; Herranz, M. L.;
   Jeronimo, J. M.; Lamy, P.; Lopez Jimenez, A.; McDonnell, J. A. M.;
   Mennella, V.; Molina, A.; Morales, R.; Moreno, F.; Palomba, E.;
   Perrin, J. M.; Rodrigo, R.; Weissman, P.; Zakharov, V.; Zarnecki, J. C.
2014JAI.....350011D    Altcode:
  GIADA (Grain Impact Analyser and Dust Accumulator) on-board the
  Rosetta mission to comet 67P/Churyumov-Gerasimenko was designed
  to study the physical and dynamical properties of dust particles
  ejected by the comet during the encounter. In this paper we report
  the results of the analysis of data collected by GIADA during the
  past seven years of the cruise phase. During this period the GIADA
  detection subsystems were switched on for periodic in-flight payload
  checkouts to monitor their state-of-health including potential changes
  in its performance that could affect its data collection. Only slight
  variations in sensitivity and dynamical range were identified that
  will not affect the GIADA measurement capability during the Rosetta
  comet encounter and rendezvous phase. The GIADA microbalance system
  detected the presence of low-volatility material over a period of
  about 169 days when the GIADA cover remained partially opened. It
  is highly probable that this material originated from the spacecraft
  itself, as a spacecraft's outgassing was observed by the ROSINA mass
  spectrometer (on-board Rosetta) during the cruise phase. <P />The
  identification of the low-volatility mass deposited on the microbalances
  as self-contamination will allow us to evaluate the mass rate background
  to be subtracted from the GIADA science data. These results obtained
  from GIADA cruise data analysis coupled with laboratory calibration data
  obtained from measurements using the GIADA spare model for selected
  cometary dust analogs will be the basis for the interpretation of the
  GIADA scientific data.

---------------------------------------------------------
Title: Possible measurements of the magnetic field in eruptive
    prominences using the PROBA-3 coronagraph
Authors: Serge, Koutchmy; Zhukov, Andrei; Dolla, Laurent; Heinzel,
   Petr; Lamy, Philippe; Bazin, Cyrille; Bommier, Veronique; Faurobert,
   Marianne
2014cosp...40E2971S    Altcode:
  The PROBA-3 mission will fly a spacecraft put in the shadow of a
  precisely occulting sister satellite orbiting “in formation” at a
  distance of 150 m in front of it to make artificial total eclipses. The
  region right above the solar limb will be studied for the first time
  over a coronal background not polluted by any spurious light. Although
  the priority will be the high-resolution fast imaging of the dynamic
  white-light corona, the use of a narrow filter centered on a low
  excitation D3 line of He I, is planned for imaging prominences. Adding
  the linear polarization analysis would permit the measurements of the
  magnetic field using the Hanle effect. We evaluate the possibility
  offered during the eruptive phase of a CME with prominence material
  inserted inside, for studying the associated magnetic field changes
  related to both the heating process and the ejection of material. The
  background highly polarized K-corona is taken into account. Sequences of
  quasi- simultaneous white-light processed images at high resolution are
  an additional feature of great interest for interpreting the overall
  magnetic structure.

---------------------------------------------------------
Title: Observation of the prominence cavity region using slitless
    eclipse flash spectra and space borne EUV filtergrams
Authors: Bazin, Cyrille; Koutchmy, Serge; Lamy, Philippe; Tavabi, Ehsan
2014IAUS..300..151B    Altcode:
  We used total solar eclipse free of parasitic light for studying the
  prominence to corona interface, and the corresponding cavity in the
  context of the coronal physics. We analysed the visible continuum
  between the prominences to directly look at the electron density. We
  demonstrate some enhanced heating in the cavity region. Some
  similarities with the interface regions are shown: the photosphere
  to the chromosphere and the prominence to the corona interface. The
  optically thin neutral Helium at 4713 Å and the singly ionized Helium
  4686 Å Paschen α lines are considered. We summed 80 slitless visible
  eclipse flash spectra that we compare with simultaneously obtained
  EUV SWAP/Proba2 174 Å images of ESA and AIA/SDO 171Å 193 Å 304 Å
  and 131 Å filtergrams. Intensity profiles in a radial direction are
  studied. We deduce the variation of the intensity ratio I(He I 4713)
  / I(He II 4686). Discussion: the temperature rises at the edge of the
  prominences. We evaluate for the first time with spectrophotometric
  accuracy the continuum modulations in prominence spectra. W-L intensity
  deficits are observed near the prominence boundaries in both eclipse
  spectra and in EUV images, confirming that the prominence -cavity
  regions correspond to a relative depression of plasma density of the
  surrounding corona. Conclusion: we demonstrate some enhanced heating
  occurring in these regions assuming hydrostatic equilibrium.

---------------------------------------------------------
Title: Comparing the solar minima of cycles 22/23 and 23/24: The
    view from LASCO white light coronal images
Authors: Lamy, P.; Barlyaeva, T.; Llebaria, A.; Floyd, O.
2014JGRA..119...47L    Altcode:
  The Large Angle and Spectrometric Coronagraph LASCO-C2 aboard SOHO has
  now completed 17 years (1996-2012) of quasi-continuous white-light
  imaging of the corona from 2.2 to 6.5 solar radii, thus allowing
  an unprecedented view of its evolution over a solar cycle and a half
  including the minima of solar cycles 22/23 and 23/24. The corrected and
  calibrated polarization sequences produce images of the radiance (B),
  the polarized radiance (pB), and the electron density N<SUB>e</SUB>
  of the K corona, and, in turn, of their synoptic maps. Their temporal
  variations are quantified by integration first globally, then in the
  north and south hemispheres, and finally, in sectors of 30° latitudinal
  extent centered along the equatorial and polar directions. The global
  radiance of the K corona follows well the solar activity as described
  by the sunspot number and the radio flux and was 24% fainter during the
  minimum of solar cycle 23/24 than during that of cycle 22/23. However,
  the two hemispheres experienced different reductions, 17% for the north
  one and 29% for the south one. The equatorial sector suffered a drastic
  reduction of 44%, in remarkable agreement with the in situ measurements
  of Wind and ACE at 1 AU, whereas the north and south polar sectors did
  not experience much variation. Cycle 23 is estimated to have lasted
  12 years and 3 months. Maximum conditions have been reached in the
  northern region, whereas the southern region is still lagging. Finally,
  the rate of coronal mass ejections follows well the solar activity.

---------------------------------------------------------
Title: Coronal mass ejections (CMEs) during the ascending phase of
    cycle 24
Authors: Lamy, Philippe; Floyd, Olivier; Barlyaeva, Tatiana
2014cosp...40E1745L    Altcode:
  The Artemis-II catalog of coronal mass ejections (Floyd et al.,
  Solar Phys 2013) lists their properties (date and time of appearance,
  position angle, angular width, mass and kinetic energy) based on
  detection and measurements performed on synoptic maps constructed from
  the calibrated SOHO/LASCO-C2 images of the K-corona from January 1996
  to December 2010. It has now been extended to 2013 allowing an analysis
  of their properties during the ascending phase of solar cycle 24 and
  a comparison with the previous cycle. In addition, these properties
  are compared to three indices of solar activity, the international
  sunspot number (SSN), the sunspot area (SSA) and the radio flux at
  10.7~cm (F10.7), either globally or separately in the North and South
  hemispheres in the case of the first two proxies. The monthly averaged
  number and mass of CMEs exhibit a time shift of 12 years and 9 months
  between the ascending phases of cycles 23 and 24, in agreement with
  the anomanously long 23/24 minimum. Both are significantly less during
  the present cycle than the previous one in agreement with a weak cycle
  24. There are strong linear correlations of the monthly averaged number
  and mass of CMEs with both SSA and F10.7 but less so with SSN. However
  two significantly different regimes are observed for the whole cycle
  23 and for the ascending phase of cycle 24 implying a comparatively
  larger CME activity after 2009 with respect to both SSA and F10.7. The
  analysis in separate hemispheres reveals a contrasted situation with
  significantly different rates and different linear correlations with
  the proxies. Possible origins of these differences will be discussed.

---------------------------------------------------------
Title: The WATCHER Heliospheric and Spaceweather Mission
Authors: Lamy, Philippe; Xia, Lidong
2014cosp...40E1746L    Altcode:
  Coronal mass ejections (CMEs) and their interplanetary counterparts
  ICMEs and corotating interaction region (CIRs) are the main disturbances
  of solar origin that impact Earth’s magnetosphere resulting in
  geomagnetic storms. In addition, CMEs can drive shock starting very
  close to the Sun than can therefore hit the Earth contrary to CIRs
  shocks which form beyond 1 AU. We present the WATCHER mission with
  the dual purpose of providing key scientific data on the two primary
  sources of spaceweather and directly serving the very purposes of
  spaceweather forecast. This will be achieved by placing a three-axis
  stabilized satellite on the Earth-L5 (Lagrangian point) arc at an offset
  angle of 30-60° from Earth and an adequate payload combining remote
  and in situ capabilities. From this ideal position and overlooking the
  region extending from the Sun to 1 AU, it will act as a CME/ICME and CIR
  watcher and sample the local solar wind. WATCHER will be able to provide
  advanced warning of solar eruptions, CMEs, CIRs and shocks well before
  their detection by Earth-based or L1 space-based observatories. WATCHER
  mission will address the following science objectives. 1. Determine the
  magnetic conditions in the Sun interior and at its surface precursors
  of interplanetary disturbances terrestrial observations. 2. Detect
  and track interplanetary disturbances (CMEs/ICMEs and CIRs) from their
  sources to Earth and determine their magnetic structure. 3. Determine
  where shocks form and how they evolve. 4. Understand the role of
  interactions affecting the propagation of disturbances (especially
  CMEs) and how they affect their arrival time at Earth. 5. Study the
  Sun-Earth relations as a global, complex system. The WATCHER S/C will
  carry the following suite of instruments. A Magnetic and Doppler
  Imager will i) measure the photospheric magnetic field and acquire
  magnetograms allowing observing the source regions of CMEs before they
  rotate to Earth view, ii) measure velocity fields allowing performing
  stereo heliosismology in combination with other observatories probing
  the convection zone where the Sun acquires its magnetism. A combined
  disk imager and inner coronal imager in EUV. EUV images offer several
  diagnostics of eruptions, indicate the solar source location of CMEs,
  and map coronal holes. They will provide advanced warning of active
  regions that would be rotating on to the disk to face Earth and of HSS
  and CIRs. A white light coronagraph will then observe, characterize and
  track CMEs up to about 20 solar radii (Rs). A couple of heliospheric
  imagers will pursue the tracking to 1 AU. A Solar Wind Plasma Instrument
  and a magnetometer will make in-situ measurements of the solar wind
  providing information on CIRs that would arrive at Earth about 4
  days after being detected in situ. Possible additional candidates,
  depending on S/C resources are a low-frequency radiotelescope with
  spectral coverage of 2-100 Rs to identify CMEs driving shocks and an
  energetic particle detector to address the unsolved issue of flare
  and CME-shock contributions to large SEP events.

---------------------------------------------------------
Title: The Characteristics and Evolution of the Dust Coma of Comet
    C/2012 S1 (ISON)
Authors: Li, Jian-Yang; Kelley, M. S.; Knight, M. M.; Farnham, T.;
   Weaver, H. A.; A'Hearn, M. F.; Mutchler, M. J.; Kolokolova, L.; Lamy,
   P. L.; Toth, I.; Xia, K.
2014AAS...22321806L    Altcode:
  C/2012 S1 (ISON) is a dynamically new comet with a sungrazing perihelion
  only 1.7 solar radii from the Sun's surface, which makes it unique
  among the known comets. The discovery of C/ISON in September 2012
  at a heliocentric distance of ~6 AU is more than one year before its
  perihelion in November 2013, allowing a detailed characterization as
  the comet moves from the frigid conditions of the outer solar system
  to extreme heating during its close passage near the Sun. As part
  of an international observing campaign, the Hubble Space Telescope
  (HST) imaged the comet in multiple epochs from April to October 2013
  pre-perihelion to characterize its dust coma at 4.15, 3.78, and 1.50
  AU. We report on our analysis of these HST images, including the
  dust production rate, the dust coma colors and morphology, and the
  rotation pole of the nucleus. The first two epochs of observations
  showed that C/ISON displays a color variations in its dust coma within
  ~5000 km from the nucleus that is best explained by the existence and
  sublimation of water ice grains. The pole orientation, as measured
  from the sunward jet, suggests a high obliquity, and indicates that
  the nucleus of C/ISON always faces the Sun with one hemisphere until
  about a week before the perihelion. We will use the observations in
  October to search for any evolutionary changes in the coma, and to
  refine the determination of the rotation pole.

---------------------------------------------------------
Title: Physical properties of craters on the Achaia region of asteroid
    (21) Lutetia
Authors: Auger, A.; Bouley, S.; Jorda, L.; Groussin, O.; Baratoux,
   D.; Capanna, C.; Lamy, P. L.
2013AGUFM.P23A1755A    Altcode:
  The Rosetta spacecraft flew by the main-belt asteroid (21) Lutetia
  on 10 July 2010. Images of the surface were acquired with the Narrow
  Angle Camera, from which Digital Terrain Models (DTM) of the surface
  were produced. These DTMs give access to the topography to study the
  physical properties of the craters of the asteroid. In this study,
  we focus on their depth-to-diameter ratio (d/D) to study their
  degradation. The d/D ratios are are derived from the DTM of Jorda et
  al. (2012), based on the method of Gaskell et al. (2008), which offers
  the best compromise between spatial resolution and the accuracy of the
  topographic reconstruction. Our values differ notably from previous
  studies (Vincent et al., 2012; Thomas et al., 2012). The discrepancy
  has been found to result from the fact that the local slope of the
  terrains on which the craters formed is ignored in these studies,
  whereas we rigorously takes this into account in our calculations. As
  a consequence, we find that d/D values for the fresh craters of Lutetia
  are consistent with the values found on other asteroids of similar size
  (within on order of magnitude) like (243) Ida or (951) Gaspra (Carr et
  al., 1994; Sullivan et al., 1996). The Achaia region may be divided
  into three units based on geomorphological analysis. A comparison of
  the crater density on the three units suggests two different ages, the
  youngest part corresponding to the Nicaea crater unit. Interestingly,
  the mean d/D values of the three units are different. The craters of
  these units were therefore differently affected by geological events
  (e.g., essentially impact and associated phenomena such as seismic
  shaking or ejecta blanketing) that occurred in the past history of
  Lutetia. Some of these events must be recent since several lineaments
  intersect most craters of one of the unit. Ejecta deposits have been
  previously noted on one part of Achaia and provide a good explanation
  for the low d/D values on this unit. Moreover, we suggest that tectonic
  activity may have been responsible for the erasure of small craters. The
  link between these events and the impacts at the origin of the North
  Polar Crater Cluster of Lutetia will be discussed.

---------------------------------------------------------
Title: Pre-perihelion characterization of Comet C/2012 S1 (ISON)
Authors: Li, J.; Kelley, M. S.; Farnham, T. L.; A'Hearn, M. F.;
   Knight, M. M.; Weaver, H. A.; Mutchler, M.; Lamy, P. L.; Toth, I.
2013AGUFM.P24A..02L    Altcode:
  Comet C/2012 S1 (ISON) is a dynamically new comet on a sungrazing
  orbit. As such, C/ISON represents a unique opportunity to study both
  the cosmic-ray-irradiated surface, produced during the comet's long
  residence in the Oort cloud, and much deeper layers in the nucleus,
  exposed when the comet passes within 2 solar radii of the Sun at
  perihelion. During the first phase of our investigation, we collected
  broadband images of C/ISON on April 10, 2012 at a heliocentric distance
  of 4.15 AU, using the Hubble Space Telescope WFC3/UVIS. We used the
  F606W and F438W filters in three HST orbits covering a total span of ~19
  hrs. The comet shows a well delineated coma in the sunward direction
  extending about 2" from the nucleus, and a dust tail at least 25"
  long. The coma has an average red color of 5%/0.1 micron within 1.6"
  from the nucleus, becoming redder towards the tail. Both the color
  and the size of the coma in the sunward direction are consistent
  with outflow of micron sized dust. Broadband photometry yielded Afρ
  of 1376 cm at 589 nm, and 1281 cm at 433 nm, measured with a 1.6"
  radius aperture. The total brightness of the comet within a 0.12"
  radius aperture remained unchanged within 0.03 mag for the entire
  duration of the observations. A well defined sunward jet is visible
  after removing the 1/ρ brightness distribution. The jet is centered
  at position angle 290 deg (E of Celestial N), with a cone angle of 45
  deg, a projected length of 1.6", and a slight curvature towards the
  north near the end. No temporal change in the morphology is observed,
  suggesting the jet is circumpolar. Under this assumption, the jet's
  apparent position constrains the rotational pole to lie within 30 deg
  of (RA, Dec) = (330, 0), and an obliquity of 50-80 deg. Preliminary
  analysis using a coma-nucleus separation technique suggests a nuclear
  radius less than 2 km. The survival of such a small nucleus during
  its perihelion at 2.7 solar radii is certainly questionable.

---------------------------------------------------------
Title: Characterizing the Dust Coma of Comet C/2012 S1 (ISON) at
    4.15 AU from the Sun
Authors: Li, Jian-Yang; Kelley, Michael S. P.; Knight, Matthew M.;
   Farnham, Tony L.; Weaver, Harold A.; A'Hearn, Michael F.; Mutchler,
   Max J.; Kolokolova, Ludmilla; Lamy, Philippe; Toth, Imre
2013ApJ...779L...3L    Altcode: 2013arXiv1311.0826L
  We report results from broadband visible images of comet C/2012 S1
  (ISON) obtained with the Hubble Space Telescope Wide Field Camera 3
  on 2013 April 10. C/ISON's coma brightness follows a 1/ρ (where ρ
  is the projected distance from the nucleus) profile out to 5000 km,
  consistent with a constant speed dust outflow model. The turnaround
  distance in the sunward direction suggests that the dust coma is
  composed of sub-micron-sized particles emitted at speeds of tens of
  m s<SUP>-1</SUP>. A(θ)fρ, which is commonly used to characterize
  the dust production rate, was 1340 and 1240 cm in the F606W and
  F438W filters, respectively, in apertures &lt;1.”6 in radius. The
  dust colors are slightly redder than solar, with a slope of 5.0% ±
  0.2% per 100 nm, increasing to &gt;10% per 100 nm 10,000 km down the
  tail. The colors are similar to those of comet C/1995 O1 (Hale-Bopp)
  and other long-period comets, but somewhat bluer than typical values for
  short-period comets. The spatial color variations are also reminiscent
  of C/Hale-Bopp. A sunward jet is visible in enhanced images, curving
  to the north and then tailward in the outer coma. The 1.”6 long
  jet is centered at a position angle of 291°, with an opening angle
  of ~45°. The jet morphology remains unchanged over 19 hr of our
  observations, suggesting that it is near the rotational pole of the
  nucleus, and implying that the pole points to within 30° of (R.A.,
  decl.) = (330°, 0°). This pole orientation indicates a high obliquity
  of 50°-80°.

---------------------------------------------------------
Title: ARTEMIS II: A Second-Generation Catalog of LASCO Coronal Mass
    Ejections Including Mass and Kinetic Energy
Authors: Floyd, O.; Lamy, P.; Boursier, Y.; Llebaria, A.
2013SoPh..288..269F    Altcode:
  The ARTEMIS-I catalog of coronal mass ejections (CMEs) was initially
  developed on a first generation of low-resolution synoptic maps
  constructed from the SOHO/LASCO-C2 images of the K-corona and resulted
  in an online database listing all events detected since January 1996
  (Boursier et al., Solar Phys.257, 125, 2009). A new generation of
  synoptic maps with higher temporal (a factor of 1.5) and angular
  (a factor of 2.5) resolutions allowed us to reconsider the question
  of CME detection and resulted in the production of a new catalog:
  ARTEMIS-II. The parameters estimated for each detected CME are still
  the date and time of appearance, the position angle, the angular width,
  and (when detected at several solar distances) the global and median
  velocities. The new synoptic maps correct for the limited number of
  velocity determinations reported in the ARTEMIS-I catalog. We now
  determine the propagation velocity of 79 % of detected CMEs instead
  of 30 % in the previous version. A final major improvement is the
  estimation of the mass and kinetic energy of all CMEs for which we
  could determine the velocity, that is ≈ 13 000 CMEs until December
  2010. Individual comparisons of velocity determination of 23 CMEs
  for which a full three-dimensional kinematical solution has been
  published indicate that ARTEMIS-II performs extremely well except at
  the highest velocities, an intrinsic limitation of our method. Finally,
  individual comparisons of mass determination of seven CMEs for which
  a robust solution has been obtained from stereographic observations
  demonstrate the quality of the ARTEMIS-II results.

---------------------------------------------------------
Title: Sunskirting comets discovered with the LASCO coronagraphs
    over the decade 1996-2008
Authors: Lamy, P.; Faury, G.; Llebaria, A.; Knight, M. M.; A'Hearn,
   M. F.; Battams, K.
2013Icar..226.1350L    Altcode:
  In addition to an unprecedented number of Kreutz sungrazing comets, the
  LASCO coronagraphs have discovered some 238 unrelated “sunskirting”
  comets over the 12 years from 1996 to 2008. This new class is organized
  in several groups, and at least two comets have further been found
  periodic. This article presents the photometry and the heliocentric
  light curves of these 238 sunskirting comets. The bulk of them exhibit
  a continuous increase of the brightness as the comet approaches the
  Sun, reach a peak before perihelion and then progressively fade with
  a large variety of brightness gradients. However some of them have
  peak brightness either at or post-perihelion, whereas a quite large
  number are approximately flat. Likewise for the sungrazers, we find a
  color effect prominent between 8 and 40R<SUB>⊙</SUB> (solar radii)
  which we interpret as resulting from the emission lines of the Na I
  doublet (D lines). We finally characterize the different groups of
  sunskirters on the basis of their cumulative distribution function of
  the peak brightness and of their fragmentation history.

---------------------------------------------------------
Title: Early pre-perihelion characterization of Comet C/2012 S1 (ISON)
Authors: Li, Jian-Yang; Kelley, M. S.; Farnham, T. L.; A'Hearn, M. F.;
   Knight, M. M.; Weaver, H. A.; Mutchler, M. J.; Lamy, P.; Toth, I.
2013DPS....4540702L    Altcode:
  Comet C/2012 S1 (ISON) is a dynamically new comet on a sungrazing
  orbit. As such, C/ISON represents a unique opportunity to study both
  the cosmic-ray-irradiated surface, produced during the comet's long
  residence in the Oort cloud, and much deeper layers in the nucleus,
  exposed when the comet passes 1.7 solar radii from the Sun's surface at
  perihelion. During the first phase of our investigation, we collected
  broadband images of C/ISON on April 10, 2012 at a heliocentric distance
  of 4.15 AU, using the Hubble Space Telescope WFC3/UVIS. We used the
  F606W and F438W filters in three HST orbits covering a total span of ~19
  hrs. The comet shows a well delineated coma in the sunward direction
  extending about 2" from the nucleus, and a dust tail at least 25"
  long. The coma has an average red color of 5%/0.1 micron within 1.6"
  from the nucleus, becoming redder towards the tail. Both the color
  and the size of the coma in the sunward direction are consistent
  with outflow of micron sized dust. Broadband photometry yielded Afρ
  of 1376 cm at 589 nm, and 1281 cm at 433 nm, measured with a 1.6"
  radius aperture. The total brightness of the comet within a 0.12"
  radius aperture remained unchanged within 0.03 mag for the entire
  duration of the observations. A well defined sunward jet is visible
  after removing the 1/ρ brightness distribution. The jet is centered
  at position angle 290 deg (E of Celestial N), with a cone angle of 45
  deg, a projected length of 1.6", and a slight curvature towards the
  north near the end. No temporal change in the morphology is observed,
  suggesting the jet is circumpolar. Under this assumption, the jet’s
  apparent position constrains the rotational pole to lie within 30 deg
  of (RA, Dec) = (330, 0), and an obliquity of 50-80 deg. Preliminary
  analysis using a coma-nucleus separation technique suggests a nuclear
  radius less than 2 km. The survival of such a small nucleus during
  its sungrazing perihelion is certainly questionable.

---------------------------------------------------------
Title: Hubble Imaging of the Nucleus of Comet ISON
Authors: Lamy, Philippe
2013hst..prop13478L    Altcode:
  Comet C/2012 S1 {ISON} is both a new "nearly isotropic" and a
  sungrazing comet with anoutstanding apparition in cycle 21, passing
  within 0.42 AU of the Earth.We propose a 12-orbit Hubble postperihelion
  investigation of this comet that will provide a detailed view of its
  nucleus originating from the Oort cloud and of the possible consequences
  of its very close approach to the Sun at a perihelion distance of
  0.012471 AU such as fragmentation.We will determine the size, shape,
  rotational period, and color {UBVRI} ofthe nucleus of C/2012 S1 or of
  its fragment should disruption occurs. This passage of a new "nearly
  isotropic" comet very close tothe Earth offers a rare opportunity
  to investigate this population ofobjects, and we expect many other
  observatories to attempt detecting itsnucleus in the mid-infrared,
  millimetric and centimetric domains.Combining the Hubble results with
  those from other observatories shouldyield a comprehensive picture
  of this NIC that can be compared to thedetailed data collected on
  ecliptic comets {ECs} during the past 3decades. The differences and
  similarities between NICs and ECs shouldyield valuable insights into
  the origin and evolution of comets.

---------------------------------------------------------
Title: Millimetre continuum observations of comet C/2009 P1 (Garradd)
Authors: Boissier, J.; Bockelée-Morvan, D.; Groussin, O.; Lamy, P.;
   Biver, N.; Crovisier, J.; Colom, P.; Moreno, R.; Jorda, L.; Piétu, V.
2013A&A...557A..88B    Altcode: 2013arXiv1307.8253B
  Context. Little is known about the physical properties of the nuclei
  of Oort Cloud comets. Measuring the thermal emission of a nucleus
  is one of the few means for deriving its size and constraining some
  of its thermal properties. <BR /> Aims: We attempted to measure the
  nucleus size of the Oort Cloud comet C/2009 P1 (Garradd). <BR />
  Methods: We used the Plateau de Bure Interferometer to measure the
  millimetric thermal emission of this comet at 157 GHz (1.9 mm) and 266
  GHz (1.1 mm). <BR /> Results: Whereas the observations at 266 GHz were
  not usable due to bad atmospheric conditions, we derived a 3σ upper
  limit on the comet continuum emission of 0.41 mJy at 157 GHz. Using a
  thermal model for a spherical nucleus with standard thermal parameters,
  we found an upper limit of 5.6 km for the radius. The dust contribution
  to our signal is estimated to be negligible. Given the water production
  rates measured for this comet and our upper limit, we estimated that
  Garradd was very active, with an active fraction of its nucleus larger
  than 50%. <P />Based on observations carried out with the IRAM Plateau
  de Bure Interferometer. IRAM is supported by INSU/CNRS (France), MPG
  (Germany), and IGN (Spain).

---------------------------------------------------------
Title: THERMAP: the mid-infrared (8-16 µm) spectro-imager of the
    ESA Marco Polo R mission
Authors: Groussin, O.; Licandro, J.; Helbert, J.; Alí Lagoa, V.;
   Brageot, E.; Davidsson, B.; Delbó, M.; Delsanti, A.; Garcia-Talavera,
   M. R.; Green, S.; Jorda, L.; Knollenberg, J.; Kührt, E.; Lamy, P.;
   Lellouch, E.; Levacher, P.; Reynaud, J. -L.; Rozitis, B.; Sunshine,
   J.; Vernazza, P.
2013EPSC....8..196G    Altcode:
  THERMAP is a mid-infrared (8-16 μm) spectroimager, selected by
  the European Space Agency (ESA) in February 2013 for the scientific
  payload of the Marco Polo R M-class mission. We present in this paper
  the instrument and its scientific objectives.

---------------------------------------------------------
Title: Thermal properties, sizes, and size distribution of
    Jupiter-family cometary nuclei
Authors: Fernández, Y. R.; Kelley, M. S.; Lamy, P. L.; Toth, I.;
   Groussin, O.; Lisse, C. M.; A'Hearn, M. F.; Bauer, J. M.; Campins, H.;
   Fitzsimmons, A.; Licandro, J.; Lowry, S. C.; Meech, K. J.; Pittichová,
   J.; Reach, W. T.; Snodgrass, C.; Weaver, H. A.
2013Icar..226.1138F    Altcode: 2013arXiv1307.6191F
  We present results from SEPPCoN, an on-going Survey of the Ensemble
  Physical Properties of Cometary Nuclei. In this report we discuss
  mid-infrared measurements of the thermal emission from 89 nuclei of
  Jupiter-family comets (JFCs). All data were obtained in 2006 and 2007
  using imaging capabilities of the Spitzer Space Telescope. The comets
  were typically 4-5 AU from the Sun when observed and most showed only
  a point-source with little or no extended emission from dust. For those
  comets showing dust, we used image processing to photometrically extract
  the nuclei. For all 89 comets, we present new effective radii, and for
  57 comets we present beaming parameters. Thus our survey provides the
  largest compilation of radiometrically-derived physical properties of
  nuclei to date. We have six main conclusions: (a) The average beaming
  parameter of the JFC population is 1.03 ± 0.11, consistent with unity;
  coupled with the large distance of the nuclei from the Sun, this
  indicates that most nuclei have Tempel 1-like thermal inertia. Only
  two of the 57 nuclei had outlying values (in a statistical sense) of
  infrared beaming. (b) The known JFC population is not complete even at
  3 km radius, and even for comets that approach to ∼2 AU from the Sun
  and so ought to be more discoverable. Several recently-discovered comets
  in our survey have small perihelia and large (above ∼2 km) radii. (c)
  With our radii, we derive an independent estimate of the JFC nuclear
  cumulative size distribution (CSD), and we find that it has a power-law
  slope of around -1.9, with the exact value depending on the bounds
  in radius. (d) This power-law is close to that derived by others from
  visible-wavelength observations that assume a fixed geometric albedo,
  suggesting that there is no strong dependence of geometric albedo with
  radius. (e) The observed CSD shows a hint of structure with an excess
  of comets with radii 3-6 km. (f) Our CSD is consistent with the idea
  that the intrinsic size distribution of the JFC population is not a
  simple power-law and lacks many sub-kilometer objects.

---------------------------------------------------------
Title: The persistent activity of Jupiter-family comets at 3-7 AU
Authors: Kelley, Michael S.; Fernández, Yanga R.; Licandro, Javier;
   Lisse, Carey M.; Reach, William T.; A'Hearn, Michael F.; Bauer,
   James; Campins, Humberto; Fitzsimmons, Alan; Groussin, Olivier; Lamy,
   Philippe L.; Lowry, Stephen C.; Meech, Karen J.; Pittichová, Jana;
   Snodgrass, Colin; Toth, Imre; Weaver, Harold A.
2013Icar..225..475K    Altcode: 2013arXiv1304.3818K
  We present an analysis of comet activity based on the Spitzer Space
  Telescope component of the Survey of the Ensemble Physical Properties
  of Cometary Nuclei. We show that the survey is well suited to measuring
  the activity of Jupiter-family comets at 3-7 AU from the Sun. Dust was
  detected in 33 of 89 targets (37 ± 6%), and we conclude that 21 comets
  (24 ± 5%) have morphologies that suggest ongoing or recent cometary
  activity. Our dust detections are sensitivity limited, therefore
  our measured activity rate is necessarily a lower limit. All comets
  with small perihelion distances (q &lt; 1.8 AU) are inactive in our
  survey, and the active comets in our sample are strongly biased to
  post-perihelion epochs. We introduce the quantity ɛfρ, intended to
  be a thermal emission counterpart to the often reported Afρ, and find
  that the comets with large perihelion distances likely have greater dust
  production rates than other comets in our survey at 3-7 AU from the Sun,
  indicating a bias in the discovered Jupiter-family comet population. By
  examining the orbital history of our survey sample, we suggest that
  comets perturbed to smaller perihelion distances in the past 150 yr
  are more likely to be active, but more study on this effect is needed.

---------------------------------------------------------
Title: Photometric Calibration of the LASCO-C2 Coronagraph over 14
    Years (1996 - 2009)
Authors: Gardès, B.; Lamy, P.; Llebaria, A.
2013SoPh..283..667G    Altcode:
  We present a photometric calibration of the SOHO/LASCO-C2 coronagraph
  based on the analysis of all stars down to magnitude V=8 that transited
  its field of view during the past 14 years of operation (1996 - 2009),
  extending the previous work of Llebaria, Lamy, and Danjard (Icarus182,
  281, 2006). The pre-processing of the images incorporates the most
  recent determination of the evolution of the LASCO-C2 performances. The
  automatic procedure then analyzes some 260 000 images to detect,
  locate, and measure those stars. Aperture photometry is performed
  using four different aperture sizes, and the zero points (ZPs)
  of the photometric transformations between the LASCO-C2 magnitudes
  for its orange filter and the standard V magnitudes are determined
  after introducing a correction for the color of the stars. A new
  statistical method ("bootstrap") is introduced to assess the confidence
  intervals of the mean yearly value of the ZPs. The correction for finite
  aperture required to derive the calibration coefficient for the surface
  photometry of extended sources is based on the reconstructed image of
  bright saturated stars and a robust model for the growth curve. The
  global temporal evolution of the sensitivity of LASCO-C2 is compatible
  with a continuous decrease at a rate of ≈ 0.56 % per year. However,
  it is better described by two separate linear variations with a
  discontinuity at the time of the loss of SOHO. After the resumption
  of normal operations in 1999, the linear decrease of the sensitivity
  amounts to ≈ 0.35 % per year.

---------------------------------------------------------
Title: Comet C/2012 S1 (Ison)
Authors: Li, Jian-Yang; Weaver, H. A.; Kelley, M. S.; Farnham, T. L.;
   A'Hearn, M. F.; Knight, M. M.; Mutchler, M. J.; Lamy, P.; Toth, I.;
   Yoshimoto, K.; Gonzalez, J. J.; Shurpakov, S.; Pilz, U.; Scarmato, T.
2013CBET.3496....1L    Altcode: 2013CBET.3496....1W
  Jian-Yang Li, Planetary Science Institute; H. A. Weaver, Applied Physics
  Laboratory, Johns Hopkins University; M. S. Kelley, T. L. Farnham, and
  M. F. A'Hearn, University of Maryland; M. M. Knight, Lowell Observatory;
  M. J. Mutchler, Space Telescope Science Institute; P. Lamy, Laboratoire
  d'Astrophysique de Marseille; and I. Toth, Hungarian Academy of
  Sciences, obtained broadband images of comet C/2012 S1 (cf. CBET 3238)
  on Apr. 10 (when at r = 4.15 AU and D = 4.24 AU) using the Hubble Space
  Telescope (HST) WFC3/UVIS cameras with the F606W and F438W filters. The
  observations were performed in three HST orbits, with the second orbit
  about 2.5 hr after the first, and the last about 13.5 hr from the
  second. Preliminary analysis using a coma-nucleus separation technique
  (cf. Lamy et al. 2009, A.Ap. 508, 1045) suggests a nuclear radius less
  than 2 km. The total brightness of the comet within a 0".24-diameter
  aperture remained unchanged within 0.03 mag over the 19-hr observing
  window. Broadband photometry yielded Af(rho) = 1376 cm at 589 nm, and
  1281 cm at 433 nm, consistent with a red slope of 5 percent per 0.1
  micron for the coma dust. A well-defined jet is visible after removing
  the 1/r brightness distribution. The jet is centered on position angle
  290 deg, with a cone angle of 45 deg, a projected length of 1".6, and a
  slight curvature towards the north near the end. No temporal change in
  the morphology is observed over the three epochs, suggesting that the
  jet is circumpolar. Under this assumption, the jet's apparent position
  constrains the rotational pole to lie within 30 deg of R.A. = 330 deg,
  Decl. = 0 deg (equinox 2000.0). The images are posted at the following
  website URL: http://hubblesite.org/newscenter/archive/releases/2013/14/.
  Total-magnitude estimates (visual unless otherwise noted):
  2012 Oct. 14.77 UT, 17.3 (K. Yoshimoto, Yamaguchi, Japan, 0.16-m
  reflector + CCD); Dec. 19.82, 16.5 (Yoshimoto); 2013 Jan. 13.90, 14.8
  (J. J. Gonzalez, Leon, Spain, 0.20-m reflector; visual); 21.85, 15.8
  (S. Shurpakov, Baran', Belarus, 20-cm reflector + CCD); Feb. 2.90,
  15.0 (U. Pilz, Leipzig, Germany, 32-cm reflector; visual); 11.57, 15.8
  (Yoshimoto); 23.74, 15.8 (Shurpakov); Mar. 6.72, 15.5 (Shurpakov);
  10.76, 16.1 (T. Scarmato, Calabria, Italy, 25-cm reflector + CCD +
  R_c filter); 23.79, 15.8 (Scarmato); Apr. 6.82, 16.2 (Scarmato); 9.48,
  15.8 (Yoshimoto); 19.81, 16.2 (Scarmato).

---------------------------------------------------------
Title: A new multiresolution method applied to the 3D reconstruction
    of small bodies
Authors: Capanna, C.; Jorda, L.; Lamy, P. L.; Gesquiere, G.
2012AGUFM.P23B1937C    Altcode:
  The knowledge of the three-dimensional (3D) shape of small solar system
  bodies, such as asteroids and comets, is essential in determining
  their global physical properties (volume, density, rotational
  parameters). It also allows performing geomorphological studies of
  their surface through the characterization of topographic features,
  such as craters, faults, landslides, grooves, hills, etc.. In the case
  of small bodies, the shape is often only constrained by images obtained
  by interplanetary spacecrafts. Several techniques are available to
  retrieve 3D global shapes from these images. Stereography which relies
  on control points has been extensively used in the past, most recently
  to reconstruct the nucleus of comet 9P/Tempel 1 [Thomas (2007)]. The
  most accurate methods are however photogrammetry and photoclinometry,
  often used in conjunction with stereography. Stereophotogrammetry
  (SPG) has been used to reconstruct the shapes of the nucleus of
  comet 19P/Borrelly [Oberst (2004)] and of the asteroid (21) Lutetia
  [Preusker (2012)]. Stereophotoclinometry (SPC) has allowed retrieving
  an accurate shape of the asteroids (25143) Itokawa [Gaskell (2008)] and
  (2867) Steins [Jorda (2012)]. We present a new photoclinometry method
  based on the deformation of a 3D triangular mesh [Capanna (2012)]
  using a multi-resolution scheme which starts from a sphere of 300
  facets and yields a shape model with 100; 000 facets. Our strategy is
  inspired by the "Full Multigrid" method [Botsch (2007)] and consists
  in going alternatively between two resolutions in order to obtain an
  optimized shape model at a given resolution before going to the higher
  resolution. In order to improve the robustness of our method, we use
  a set of control points obtained by stereography. Our method has been
  tested on images acquired by the OSIRIS visible camera, aboard the
  Rosetta spacecraft of the European Space Agency, during the fly-by of
  asteroid (21) Lutetia in July 2010. We present the corresponding 3D
  shape model of its surface and compare it with models obtained with
  the SPG and SPC methods. We finally illustrate the practical interest
  of our approach in geomorphological studies through an analysis of
  depth to diameter ratio of several craters and topographic properties
  of other features. Botsch, M., et al., "Geometric modeling based on
  polygonal meshes," Proc. ACM SIGGRAPH Course Notes, 2007 Capanna,
  C., et al.: 3D Reconstruction of small solar system bodies using
  photoclinometry by deformation, IADIS International Journal on Computer
  Science and Information Systems, in press, 2012. Gaskell, R. W., et
  al.: Characterizing and navigating small bodies with imaging data,
  Meteoritics and Planetary Science, vol 43, p. 1049, 2008. Jorda, L.,
  et al: Asteroid (2867) Steins: Shape, Topography and Global Physical
  Properties from OSIRIS observations, Icarus, in press, 2012. Oberst,
  J., et al.: The nucleus of Comet Borrelly: a study of morphology
  and surface brightness, Icarus, vol. 167, 2004. Preusker, F., et
  al.: The northern hemisphere of asteroid 21 Lutetia topography and
  orthoimages from Rosetta OSIRIS NAC image data, Planetary and Space
  Science, vol. 66, p. 54-63, 2012. Thomas, P. C., et al.: The shape,
  topography, and geology of Tempel 1 from Deep Impact observations,
  Icarus, vol. 187, Issue 1, p. 4-15, 2007

---------------------------------------------------------
Title: Testing a Two-temperature Model of the Solar Corona with
    Empirically-derived Plasma parameters
Authors: Strachan, L.; Panasyuk, A.; Lamy, P. L.; van der Holst, B.;
   Oran, R.; Frazin, R. A.; Manchester, W. B.
2012AGUFMSH31B..04S    Altcode:
  We compare the plasma parameters predicted from the Michigan
  two-temperature chromosphere-corona model to those parameters obtained
  from the analyses of UVCS and LASCO data. The empirical data are
  organized as Carrington rotation maps for the electron densities, proton
  kinetic temperatures, and outflow velocities. This data format makes
  it convenient for understanding the differences between the modeled and
  observed latitudinal variations in the plasma parameters. In addition,
  we discuss the model performance for characterizing streamers and
  coronal holes at different phases in the solar activity cycle. These
  tests are useful for investigating how well coronal and solar wind
  models simulate the underlying physical processes that operate in the
  solar corona.

---------------------------------------------------------
Title: Disk-resolved photometry of Asteroid (2867) Steins
Authors: Spjuth, S.; Jorda, L.; Lamy, P. L.; Keller, H. U.; Li, J. -Y.
2012Icar..221.1101S    Altcode:
  We present a new method to perform disk-resolved photometry in order
  to investigate the intrinsic photometric properties of the surface
  of small Solar System bodies. We adopt the standard approach where
  a shape model is combined with a photometric formalism - in practise
  the Hapke formalism - to remove the effects of topography and recover
  the photometric (Hapke) parameters of either the global surface or, in
  its most elaborated form, the spatial variations of these parameters
  across the surface. Our method operates in the space of the facets
  representing the three-dimensional shape of the body, whereas all past
  analysis have always been performed in the space of the image pixels
  although they are not intrinsic to the surface of the body. This has
  the advantage of automatically tracking the same local surface element
  on a series of images. We first apply our method to images of the
  nucleus of Comet 9P/Tempel 1 obtained by the High-Resolution Imager
  (HRI) instrument on board the Deep Impact spacecraft and our derived
  Hapke parameters are in good agreement with those published by Li et
  al. (Li, J.-Y. et al. [2007]. Icarus 187, 41-55) within their respective
  uncertainties. We confirm the presence of an extended region of higher
  roughness in the southern hemisphere of the nucleus and the higher
  albedo of the ice-rich regions identified by Sunshine et al. (Sunshine,
  J.M. et al. [2006]. Science 311, 1453-1455) near the equator. The
  photometric properties of Asteroid (2867) Steins are then studied
  from multi-spectral images obtained with the OSIRIS Wide Angle Camera
  (WAC) on board the Rosetta spacecraft during its flyby on 5 September
  2008. Our analysis indicates that the surface is highly porous (∼84%)
  and that it exhibits both a shadow-hiding opposition effect (SHOE)
  and probably, a coherent-backscatter opposition effect (CBOE). The
  single scattering albedo is the highest (SSA = 0.57) ever observed among
  small bodies visited by spacecrafts. Our modelled roughness parameter
  is indicative of a high microscale roughness. The surface of Steins
  may in fact exhibit a fractal surface with high roughness present on a
  large range of scales, from micrometers to centimeters. The geometric
  and Bond albedos are calculated with the Hapke parameters yielding
  A<SUB>p</SUB> = 0.39 ± 0.02 and A<SUB>B</SUB> = 0.24 ± 0.01. This high
  albedo is consistent with an iron-poor surface composition similar to
  aubrite meteorites which are suspected to originate from the E-type
  asteroids. We find no photometric variations on the surface at the
  (limited) spatial resolution of the WAC images.

---------------------------------------------------------
Title: Asteroid (2867) Steins: Shape, topography and global physical
    properties from OSIRIS observations
Authors: Jorda, L.; Lamy, P. L.; Gaskell, R. W.; Kaasalainen, M.;
   Groussin, O.; Besse, S.; Faury, G.
2012Icar..221.1089J    Altcode:
  The Rosetta spacecraft flew by Asteroid (2867) Steins on 5 September
  2008, allowing the onboard OSIRIS cameras to collect the first
  images of an E-type asteroid. We implemented several three-dimensional
  reconstruction techniques to retrieve its shape. Limb profiles, combined
  with stereo control points, were used to reconstruct an approximate
  shape model. This model was refined using a stereophotoclinometry
  technique to accurately retrieve the topography of the hemisphere
  observed by OSIRIS. The unseen part of the surface was constrained
  by the technique of light curves inversion. <P />The global shape
  resembles a top with dimensions along the principal axes of inertia
  of 6.83 × 5.70 × 4.42 km. It is conspicuously more regular than
  other small asteroids like (233) Eros and (25143) Itokawa. Its mean
  radius is R<SUB>m</SUB> = 2.70 km and its equivalent radius (radius
  of a sphere of equivalent volume) is R<SUB>v</SUB> = 2.63 km. The
  north pole is oriented at RA = 99 ± 5° and Dec = -59 ± 5°, which
  implies a very large obliquity of 172° and a retrograde rotation. <P
  />Maps of the gravitational field and slopes were calculated for the
  well-imaged part of the asteroid. Together with the shape, they helped
  characterizing the most prominent topographic features identified at
  the surface of (2867) Steins: an equatorial ridge restricted to the
  extremities of the long axis, a large crater having dimensions of
  2100 × 1800 m in the southern hemisphere, and an elongated hill in
  the northern hemisphere. We conjecture that the equatorial ridge was
  formed by centrifugal acceleration as the asteroid was spun up by the
  Yarkovsky-O’Keefe-Radzievskii-Paddack effect.

---------------------------------------------------------
Title: High surface porosity as the origin of emissivity features
    in asteroid spectra
Authors: Vernazza, P.; Delbo, M.; King, P. L.; Izawa, M. R. M.;
   Olofsson, J.; Lamy, P.; Cipriani, F.; Binzel, R. P.; Marchis, F.;
   Merín, B.; Tamanai, A.
2012Icar..221.1162V    Altcode:
  Emission features in the mid-IR domain (7-25 μm) are quite ubiquitous
  among large asteroids and therefore offer the potential to uncover
  their surface composition. However, when comparing these spectra
  with the actual laboratory spectra of both minerals and meteorites,
  they do not necessarily match. Here, and in a companion paper by King
  et al. (in preparation, 2012), we show that by modifying the sample
  preparation - typically by suspending meteorite and/or mineral powder
  (&lt;30 μm) in IR-transparent KBr (potassium bromide) powder - we are
  able to reproduce the spectral behavior of those main-belt asteroids
  with emissivity features. This resulting good match between KBr-diluted
  meteorite spectra and asteroid spectra suggests an important surface
  porosity (&gt;90%) for the first millimeter for our asteroid sample. It
  therefore appears that mid-IR emission spectra of asteroids do not
  only carry information about their surface composition but they can
  also help us constraining their surface structure (under-dense versus
  compact surface structure), as suggested by Emery et al. (Emery,
  J.P., Cruikshank, D.P., van Cleve, J. [2006]. Icarus 182, 496-512) in
  the case of the Jupiter Trojans. The large surface porosity inferred
  from the mid-IR spectra of certain asteroids is also implied by two
  other independent measurements, namely their thermal inertia and their
  radar albedo. We further clarified how much compositional information
  can be retrieved from the mid-IR range by focusing our analysis on a
  single object, 624 Hektor. We showed that the mid-IR range provides
  critical constraints (i) on its origin and of that of the red Trojans
  that we locate in the formation regions of the comets, and (ii) on the
  primordial composition of the dust present in the outer region (&gt;10
  AU) of the Solar System’s protoplanetary disk. Future investigations
  should focus on finding the mechanism responsible for creating such
  high surface porosity.

---------------------------------------------------------
Title: Identification and physical properties of craters on Asteroid
    (2867) Steins
Authors: Besse, S.; Lamy, P.; Jorda, L.; Marchi, S.; Barbieri, C.
2012Icar..221.1119B    Altcode:
  We report on the physical properties of the craters of Asteroid
  (2867) Steins based on an analysis of images obtained with the OSIRIS
  instrument during the Rosetta flyby that took place on 5 September
  2008. To compensate for the limited spatial resolution of the images
  and unfavorable illumination conditions, we applied three different
  filtering techniques designed to enhance the craters detection. The
  selected images covered 44% of the overall surface of the asteroid and
  42 craters were detected. We calculated their diameter and depth using
  a forward modeling procedure that combines a global shape model with
  an idealized semi-hemispherical representation of the craters, further
  incorporating photometric properties to generate simulated images. The
  resulting images were then compared to the original images. Crater
  diameters range from 150 to 2100 m with depth-to-diameter ratios
  of 0.04-0.25, a wide range consistent with other small bodies. A
  striking dichotomy was observed between the two sides of the asteroid
  reflected by both a ratio of 3.6 between the spatial density and
  very different power exponents of the size distribution functions,
  -3.3 versus -1.5. Altogether these peculiar properties most likely
  reflect the particular history of Steins, in particular the impact
  that created the largest crater, Diamond, and extensively damaged the
  “original” Steins. A combination of various processes, including
  destruction, erasure, direct or indirect infill by seismic shaking,
  and even the YORP effect can explain the observed physical properties
  of the craters on Steins. A few craters may be drainage basins connected
  to a hypothetical fault, itself a product of the Diamond event.

---------------------------------------------------------
Title: Intercomparison of the LASCO-C2, SECCHI-COR1, SECCHI-COR2,
    and Mk4 Coronagraphs
Authors: Frazin, Richard A.; Vásquez, Alberto M.; Thompson, William
   T.; Hewett, Russell J.; Lamy, Philippe; Llebaria, Antoine; Vourlidas,
   Angelos; Burkepile, Joan
2012SoPh..280..273F    Altcode: 2012SoPh..tmp..140F
  In order to assess the reliability and consistency of white-light
  coronagraph measurements, we report on quantitative comparisons between
  polarized brightness [pB] and total brightness [B] images taken by
  the following white-light coronagraphs: LASCO-C2 on SOHO, SECCHI-COR1
  and -COR2 on STEREO, and the ground-based MLSO-Mk4. The data for this
  comparison were taken on 16 April 2007, when both STEREO spacecraft were
  within 3.1<SUP>∘</SUP> of Earth's heliographic longitude, affording
  essentially the same view of the Sun for all of the instruments. Due
  to the difficulties of estimating stray-light backgrounds in COR1 and
  COR2, only Mk4 and C2 produce reliable coronal-hole values (but not
  at overlapping heights), and these cannot be validated without rocket
  flights or ground-based eclipse measurements. Generally, the agreement
  between all of the instruments' pB values is within the uncertainties
  in bright streamer structures, implying that measurements of bright
  CMEs also should be trustworthy. Dominant sources of uncertainty and
  stray light are discussed, as is the design of future coronagraphs
  from the perspective of the experiences with these instruments.

---------------------------------------------------------
Title: Multi Element Telescope for Imaging and Spectroscopy (METIS)
    coronagraph for the Solar Orbiter mission
Authors: Antonucci, Ester; Fineschi, Silvano; Naletto, Giampiero;
   Romoli, Marco; Spadaro, Daniele; Nicolini, Gianalfredo; Nicolosi,
   Piergiorgio; Abbo, Lucia; Andretta, Vincenzo; Bemporad, Alessandro;
   Auchère, Frédéric; Berlicki, Arkadiusz; Bruno, Roberto; Capobianco,
   Gerardo; Ciaravella, Angela; Crescenzio, Giuseppe; Da Deppo, Vania;
   D'Amicis, Raffaella; Focardi, Mauro; Frassetto, Fabio; Heinzel,
   Peter; Lamy, Philippe L.; Landini, Federico; Massone, Giuseppe;
   Malvezzi, Marco A.; Moses, J. Dan; Pancrazzi, Maurizio; Pelizzo,
   Maria-Guglielmina; Poletto, Luca; Schühle, Udo H.; Solanki, Sami K.;
   Telloni, Daniele; Teriaca, Luca; Uslenghi, Michela
2012SPIE.8443E..09A    Altcode:
  METIS, the “Multi Element Telescope for Imaging and Spectroscopy”,
  is a coronagraph selected by the European Space Agency to be part of
  the payload of the Solar Orbiter mission to be launched in 2017. The
  unique profile of this mission will allow 1) a close approach to the
  Sun (up to 0.28 A.U.) thus leading to a significant improvement in
  spatial resolution; 2) quasi co-rotation with the Sun, resulting in
  observations that nearly freeze for several days the large-scale outer
  corona in the plane of the sky and 3) unprecedented out-of-ecliptic
  view of the solar corona. This paper describes the experiment concept
  and the observational tools required to achieve the science drivers
  of METIS. METIS will be capable of obtaining for the first time: •
  simultaneous imaging of the full corona in polarized visible-light
  (590-650 nm) and narrow-band ultraviolet HI Lyman α (121.6 nm); •
  monochromatic imaging of the full corona in the extreme ultraviolet
  He II Lyman α (30.4 nm); • spectrographic observations of the HI
  and He II Ly α in corona. These measurements will allow a complete
  characterization of the three most important plasma components of
  the corona and the solar wind, that is, electrons, hydrogen, and
  helium. This presentation gives an overview of the METIS imaging and
  spectroscopic observational capabilities to carry out such measurements.

---------------------------------------------------------
Title: In-orbit determination of the straylight in the SOHO/LASCO-C2
    coronagraph and its temporal evolution
Authors: Llebaria, A.; Loirat, J.; Lamy, P.
2012SPIE.8442E..26L    Altcode:
  The LASCO-C2 coronagraph aboard SOHO (the SOlar and Heliospheric
  Observatory) is continuously observing the solar corona since early
  1996. The instrument as well as the experimental context underwent
  during this period many changes and observational constraints. The
  consequences for the in-orbit calibration procedures are illustrated
  with the systematic measure of the coronagraph straylight. Disentangle
  the coronal signal and the straylight is the crucial point. The
  separation and monitoring of the straylight component rely on the
  daily sets of polarized observations of the corona and a minimal set
  of assumptions about the symmetry of the F-corona (the dust component
  of the solar corona). Four main changes have been detected since
  1996. Specific recommendations for the in-orbit calibration of future
  spatial coronagraphs will be presented.

---------------------------------------------------------
Title: THERMAP : a mid-infrared spectro-imager for the Marco Polo
    R mission
Authors: Groussin, O.; Brageot, E.; Reynaud, J. -L.; Lamy, P.; Jorda,
   L.; Licandro, J.; Helbert, J.; Knollenberg, J.; Kührt, E.; Delbó, M.
2012epsc.conf...48G    Altcode: 2012espc.conf...48G
  We present THERMAP, a mid-infrared (8-16 μm) spectro-imager based
  on uncooled micro-bolometer detector arrays. Due to the recent
  technological development of these detectors, which have undergone
  significant improvements in the last decade, we wanted to test
  their performances for a space mission to small bodies in the inner
  Solar System. THERMAP was selected by ESA in January 2012 for a one
  year assessment study, in the framework of a call for declaration
  of interest in science instrumentation for the Marco Polo R Cosmic
  Vision mission. In this paper, we present some results of this study
  and in particular demonstrate that the new generation of uncooled
  micro-bolometer detectors has all the imaging and spectroscopic
  capabilities to fulfill the scientific objectives of the Marco
  Polo R mission. THERMAP scientific objectives - The midinfrared
  instrument of the Marco Polo R mission must be able i) to determine
  the surface temperature by mapping the entire surface with an absolute
  accuracy of at least 5 K (goal 1 K) above 200 K, ii) to determine
  the thermal inertia with an accuracy of 10% and iii) to determine
  the surface composition by mapping the entire surface with a spectral
  resolution of 70 between 8 and 16 μm. The above mappings should be
  performed with a spatial resolution of 10 m for the entire surface
  (global characterization) and 10 cm for the sampling sites (local
  characterization). THERMAP imaging capabilities - In order to test the
  imaging capabilities of the THERMAP uncooled microbolometer detector,
  we set up an experiment based on a 640x480 ULIS micro-bolometer array,
  a germanium objective and a black body. Using the results of this
  experiment, we show that calibrated radiometric images can be obtained
  down to at least 258 K (lower limit of our experiment), and that two
  calibration points are sufficient to determine the absolute scene
  temperature with an accuracy better than 1.5 K. An extrapolation to
  lower temperatures provides an accuracy of about 5 K at 180 K, the
  lowest temperature the detector can measure. THERMAP spectroscopic
  capabilites - In order to test the spectroscopic performances of the
  detector, we added flux attenuating neutral density mid-infrared filters
  (transmittance: 50%, 10%, 1%) to our experiment. Our results show that
  we can perform spectroscopic measurements with a spectral resolution
  R=40-80 in the wavelength range 8-16 μm for a scene temperature larger
  than 300 K, the typical surface temperature of a Near Earth Asteroid
  at 1 AU from the Sun. THERMAP preliminary design - From the above
  results, we defined a preliminary design for the instrument. THERMAP
  is a mid-infrared (8-16 μm) spectro-imager based on two uncooled
  microbolometer arrays. It is composed of two channels, one for imaging
  and one for spectroscopy. A flip mirror allows switching between the
  two channels. Calibration is performed using deep space and two black
  bodies at known temperature. The design of the THERMAP instrument has a
  strong heritage from the MERTIS instrument on board Bepi-Colombo [1],
  which guarantees its feasibility and reliability. Our design is very
  flexible in term of operations, which is fundamental for a mission
  to a binary asteroid system (1996 FG3). The THERMAP instrument will
  be proposed for Marco Polo R and any future space missions to small
  bodies in the inner solar system.

---------------------------------------------------------
Title: THERMAP: a mid-infrared spectro-imager based on an uncooled
    micro-bolometer for space missions to small bodies of the solar system
Authors: Brageot, E.; Groussin, O.; Lamy, P.; Reynaud, J. -L.; Fargant,
   G.; Licandro, J.; Helbert, J.; Knollenberg, J.; Kührt, E.
2012SPIE.8442E..4OB    Altcode:
  We report on the feasibility study of a mid-infrared (8-18 µm)
  spectro-imager called THERMAP, based on an uncooled micro-bolometer
  detector array. Due to the recent technological development of these
  detectors, which have undergone significant improvements in the last
  decade, we wanted to test their performances for the Marco Polo R
  ESA Cosmic Vision mission. In this study, we demonstrate that the new
  generation of uncooled micro-bolometer detectors has all the imaging and
  spectroscopic capabilities to fulfill the scientific objectives of this
  mission. In order to test the imaging capabilities of the detector,
  we set up an experiment based on a 640x480 ULIS micro-bolometer
  array, a germanium objective and a black body. Using the results of
  this experiment, we show that calibrated radiometric images can be
  obtained down to at least 255 K (lower limit of our experiment), and
  that two calibration points are sufficient to determine the absolute
  scene temperature with an accuracy better than 1.5 K. Adding flux
  attenuating neutral density mid-infrared filters (transmittance: 50%,
  10%, 1%) to our experiment, we were able to evaluate the spectroscopic
  performances of the detector. Our results show that we can perform
  spectroscopic measurements in the wavelength range 8-16 µm with a
  spectral resolution of R~40-80 for a scene temperature &lt;300 K,
  the typical surface temperature of a Near Earth Asteroid at 1 AU from
  the Sun. The mid-infrared spectro-imager THERMAP, based on the above
  detector, is therefore well suited for the Marco Polo R mission.

---------------------------------------------------------
Title: Lutetia global shape and topography reconstructed with
    photoclinometry by deformation
Authors: Capanna, C.; Jorda, L.; Gesquière, G.; Lamy, P.; Kaasalainen,
   M.
2012epsc.conf..616C    Altcode: 2012espc.conf..616C
  3D reconstruction of asteroids and cometary nuclei allows us to model
  their physical, geomorphological and geological properties. We applied a
  new reconstruction method by photoclinometry based on the minimization
  of the chi-square difference between observed and synthetic images by
  deformation of a 3D triangular mesh to a set of images of asteroid (21)
  Lutetia acquired by the OSIRIS cameras aboard ESA's ROSETTA spacecraft
  in July 2010. This allowed us to retrieve an improved global shape
  of the asteroid as well as the local topography of its main features:
  the large Massalia crater, the North pole crater complex and several
  other topographic features of interest. A comparison of this model
  with those obtained with other techniques will be presented.

---------------------------------------------------------
Title: Sunskirting comets discovered with the LASCO coronagraphs
    (1996-2008)
Authors: Lamy, P.; Faury, G.; Llebaria, A.; Knight, M.; A'Hearn, M.
2012epsc.conf..308L    Altcode: 2012espc.conf..308L
  In addition to an unprecedented number of Kreutz sungrazing comets,
  the LASCO coronagraphs aboard SOHO have discovered some 238 unrelated
  "sunskirting" comets from 1996 to 2008. This new family is organized
  in several groups, and two comets have further been found periodic. We
  present the photometry and the heliocentric light curves of these
  sunskirting comets. The bulk of them exhibit a continuous increase
  of the brightness as the comet approaches, reaching a peak before
  perihelion and then progressively fading with a large variety of
  brightness gradients. However, some of them have peak brightness either
  at or post-perihelion whereas a quite large number are approximately
  flat. We finally characterize the different groups of sunskirters
  on the basis of their distribution of peak magnitudes and of their
  fragmentation history.

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Title: A portrait of the asteroid (21) Lutetia after the Rosetta flyby
Authors: Jorda, Laurent; Thomas, Nicolas; Scholten, Frank; Preusker,
   Frank; Gaskell, Robert; Lamy, Philippe; Marchi, Simone; Vernazza,
   Pierre; Carry, Benoit; Hviid, Stubbe; Sierks, Holger; Keller, Horst
   Uwe; Kaasalainen, Mikko
2012cosp...39..836J    Altcode: 2012cosp.meet..836J
  The asteroid (21) Lutetia has been observed by several instruments
  aboard ESA's ROSETTA spacecraft on July 10, 2010. The OSIRIS imaging
  system allowed the reconstruction of the topography of its surface. A
  number of intriguing features appeared on the images and/or on the
  topographic models: boulders, landslides, craters with various profiles,
  among others. The combination of these data with light curves and
  adaptive optics profiles allowed to retrieve the global shape of the
  asteroid, which yielded an estimate of its volume. Combined with the
  accurate mass determination from the radio science RSI instrument,
  a very high density of 3.4 g/cm^{3} was obtained.

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Title: Plasmoid Ejection at a Solar Total Eclipse
Authors: Koutchmy, S.; Bazin, C.; Berghmans, D.; De Groof, A.;
   Druckmüller, M.; Tavabi, E.; Engell, A.; Filippov, B.; Golub, L.;
   Lamy, Ph.; Linker, J.; Mikic, Z.; Mouette, J.; Nitschelm, Ch.; Seaton,
   D.; Slemzin, V.
2012EAS....55..223K    Altcode:
  The existence of coronal plasmoids has been postulated for many years
  in order to supply material to streamers and possibly to the solar
  wind (SW). The W-L SoHO C2 Lasco coronagraph observations were made
  under the 2.2 solar radii (R0) occulting disk to look at the ultimate
  sources of the SW; EUV imagers are preferably devoted to the analysis
  of the corona on and very near the solar disk. Here, in addition to
  eclipse white-light (W-L) snapshots, we used the new SWAP space-borne
  imager designed for the systematic survey of coronal activity in the
  EUV lines near 17.4 nm, over a field of view (FOV) up to 2 R0. Using
  summed and co-aligned images, the corona can then be evaluated for the
  1st time up to the limit of this FOV. At the time of the July 11, 2010,
  solar total eclipse a 20h continuous run of observations was collected,
  including images taken during eclipse totality from several ground
  observing locations where W-L data were collected. A plasmoid-like
  off-limb event was followed using the SWAP summed

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Title: Shape modeling technique KOALA validated by ESA Rosetta at
    (21) Lutetia
Authors: Carry, B.; Kaasalainen, M.; Merline, W. J.; Müller, T. G.;
   Jorda, L.; Drummond, J. D.; Berthier, J.; O'Rourke, L.; Ďurech,
   J.; Küppers, M.; Conrad, A.; Tamblyn, P.; Dumas, C.; Sierks, H.;
   Osiris Team; A'Hearn, M.; Angrilli, F.; Barbieri, C.; Barucci, A.;
   Bertaux, J. -L.; , Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei,
   S.; De Cecco, M.; Fornasier, S.; Fulle, M.; Groussin, O.; Gutiérrez,
   P.; Ip, W. -H. Hviid, S.; Keller, H. U.; Koschny, D.; Knollenberg,
   J.; Kramm, J. R.; Kuehrt, E.; Lamy, P.; Lara, L. M.; Lazzarin, M.;
   López-Moreno, J. J.; Marzari, F.; Michalik, H.; Naletto, G.; Rickman,
   H.; Rodrigo, R.; Sabau, L.; Thomas, N.; Wenzel, K. -P.
2012P&SS...66..200C    Altcode: 2011arXiv1112.5944C; 2012P&SS...66..200T
  We present here a comparison of our results from ground-based
  observations of asteroid (21) Lutetia with imaging data acquired during
  the flyby of the asteroid by the ESA Rosetta mission. This flyby
  provided a unique opportunity to evaluate and calibrate our method
  of determination of size, 3-D shape, and spin of an asteroid from
  ground-based observations. Knowledge of certain observable physical
  properties of small bodies (e.g., size, spin, 3-D shape, and density)
  have far-reaching implications in furthering our understanding
  of these objects, such as composition, internal structure, and
  the effects of non-gravitational forces. We review the different
  observing techniques used to determine the above physical properties
  of asteroids and present our 3-D shape-modeling technique KOALA
  - Knitted Occultation, Adaptive-optics, and Lightcurve Analysis -
  which is based on multi-dataset inversion. We compare the results we
  obtained with KOALA, prior to the flyby, on asteroid (21) Lutetia with
  the high-spatial resolution images of the asteroid taken with the OSIRIS
  camera on-board the ESA Rosetta spacecraft, during its encounter with
  Lutetia on 2010 July 10. The spin axis determined with KOALA was found
  to be accurate to within 2°, while the KOALA diameter determinations
  were within 2% of the Rosetta-derived values. The 3-D shape of the
  KOALA model is also confirmed by the spectacular visual agreement
  between both 3-D shape models (KOALA pre- and OSIRIS post-flyby). We
  found a typical deviation of only 2 km at local scales between the
  profiles from KOALA predictions and OSIRIS images, resulting in a volume
  uncertainty provided by KOALA better than 10%. Radiometric techniques
  for the interpretation of thermal infrared data also benefit greatly
  from the KOALA shape model: the absolute size and geometric albedo
  can be derived with high accuracy, and thermal properties, for example
  the thermal inertia, can be determined unambiguously. The corresponding
  Lutetia analysis leads to a geometric albedo of 0.19±0.01 and a thermal
  inertia below 40 J m<SUP>-2</SUP> s<SUP>-0.5</SUP> K<SUP>-1</SUP>, both
  in excellent agreement with the Rosetta findings. We consider this to be
  a validation of the KOALA method. Because space exploration will remain
  limited to only a few objects, KOALA stands as a powerful technique to
  study a much larger set of small bodies using Earth-based observations.

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Title: Geological map and stratigraphy of asteroid 21 Lutetia
Authors: Massironi, Matteo; Marchi, Simone; Pajola, Maurizio;
   Snodgrass, Colin; Thomas, Nicolas; Tubiana, Cecilia; Baptiste Vincent,
   Jean; Cremonese, Gabriele; da Deppo, Vania; Ferri, Francesca; Magrin,
   Sara; Sierks, Holger; Barbieri, Cesare; Lamy, Philippe; Rickman,
   Hans; Rodrigo, Rafael; Koschny, Detlef; Osiris Team
2012P&SS...66..125M    Altcode: 2012P&SS...66..125T
  The OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System)
  images acquired during the recent Rosetta fly-by of Lutetia (10th of
  July 2010), enabled us to unravel the long geological history of the
  asteroid. This is recorded on its highly varied surface which displays
  geological units of disparate ages. In particular, using images of
  the closest approach, five main regions (in turn subdivided into
  minor units) have been discriminated on the basis of crater density,
  overlapping and cross-cutting relationships, and presence of linear
  features (i.e., fractures, faults, grooves, troughs). Other regions,
  with still unclear stratigraphic position, were also recognized on
  images of lower resolution on the bases of geomorphological properties
  such as crater density, relationship with scarp and ridges, and sharp
  morphological boundaries. In this work the geological evolution of
  Lutetia surface is reconstructed through the description of its main
  units and related contacts. The oldest regions imaged during the closest
  approach (Achaia and Noricum) are pervasively affected by fractures
  and grooves and display surfaces so heavily cratered to be dated back
  to a period not far from the Late Heavy Bombardment (yielding Achaia
  a crater retention age of 3.6-3.7 Ga). A crater of 55 km diameter,
  named Massilia and corresponding to the Narbonensis region, cuts both
  Achaia and Noricum regions and probably represents the most prominent
  event of the Lutetia history. The considerable crater density on its
  floor and walls, the absence of discernable deposits related to the
  impact event, and the intense deformation of it floor - all attest to
  its relatively great age. The North Polar Cluster (Baetica region) is
  associated with smooth ejecta broadly mantling the surrounding units
  and displays few craters and no linear features, demonstrating its
  relatively young age (estimated at less than 300 Ma). The North Polar
  Crater Cluster is the product of superimposed impacts; the last one of
  24 km of diameter excavated the pre-existing ejecta up to the bedrock
  which locally outcrops at the crater rim. The ejecta of this last impact
  were involved in several gravitational phenomena testified by the great
  variety of deposits made up of mega-boulders diamictons, fine materials,
  gravitational taluses and debris, and landslide accumulations. A part
  from the big cratering events generating Massilia and the North Polar
  Crater Cluster, the Lutetia geological history is also punctuated by
  minor events still recorded by its stratigraphic record well imaged
  by the closest approach data.

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Title: The geomorphology of (21) Lutetia: Results from the OSIRIS
    imaging system onboard ESA's Rosetta spacecraft
Authors: Thomas, N.; Barbieri, C.; Keller, H. U.; Lamy, P.; Rickman,
   H.; Rodrigo, R.; Sierks, H.; Wenzel, K. P.; Cremonese, G.; Jorda, L.;
   Küppers, M.; Marchi, S.; Marzari, F.; Massironi, M.; Preusker, F.;
   Scholten, F.; Stephan, K.; Barucci, M. A.; Besse, S.; El-Maarry, M. R.;
   Fornasier, S.; Groussin, O.; Hviid, S. F.; Koschny, D.; Kührt, E.;
   Martellato, E.; Moissl, R.; Snodgrass, C.; Tubiana, C.; Vincent, J. -B.
2012P&SS...66...96T    Altcode:
  The surface of (21) Lutetia is highly complex with significant
  interactions between ancient and more recent structures. This work
  attempts to summarize the surface geomorphology observed using the
  high resolution images from OSIRIS, the imaging system onboard the
  European Space Agency's Rosetta spacecraft. A wide range of surface
  morphologies are seen including heavily cratered terrain, extensive
  sets of lineaments, young impact craters, and a ridge, the height
  of which is more than 1/5th of the mean radius of the body. Very
  young and very old terrains (as inferred from crater densities) are
  seen in close proximity. The longest continuous lineament is over
  80 km long. The lineaments show regional-dependent organization and
  structure. Several categories of lineament can be described. Lineaments
  radial to impact craters as seen on other asteroidal bodies are mostly
  absent. Although the lineaments may be of seismic origin (and possibly
  the result of several impact-induced events), impacts producing recent
  large craters place constraints on seismic phenomena. In particular,
  stronger attenuation of shocks than seen on other asteroidal bodies
  seems to be required. Inhomogeneous energy transport, possibly matching
  observed inhomogeneous ejecta deposition may offer explanations for
  some of the observed phenomena. Some impact craters show unusual
  forms, which are probably the result of impact into a surface with
  relief comparable to the resultant crater diameter and/or oblique
  impact. There is evidence that re-surfacing through landslides has
  occurred at several places on the object.

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Title: Boulders on Lutetia
Authors: Küppers, Michael; Moissl, Richard; Vincent, Jean-Baptiste;
   Besse, Sébastien; Hviid, Stubbe F.; Carry, Benoît; Grieger, Björn;
   Sierks, Holger; Keller, Horst Uwe; Marchi, Simone; OSIRIS Team;
   A'Hearn, M.; Angrilli, F.; Barbieri, C.; Barucci, A.; Bertaux, J. -L.;
   Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.;
   Fornasier, S.; Fulle, M.; Groussin, O.; Gutiérrez, P.; Ip, W. -H.,
   Jorda, L., Koschny, D.; Knollenberg, J.; Kramm, J. R.; Kührt, E.;
   Lamy, P.; Lara, L. M.; Lazzarin, M.; López-Moreno, J. J.; Marzari,
   F.; Michalik, H. Naletto, G.; Rickman, H.; Rodrigo, R.; Sabau, L.;
   Thomas, N.; Wenzel, K. -P.
2012P&SS...66...71K    Altcode: 2012P&SS...66...71T
  More than 200 boulders are among the many prominent geological
  features seen on Lutetia by the OSIRIS cameras onboard Rosetta. Most
  are concentrated around the central crater in Baetica regio with
  a few more apparently associated with Patavium crater. The size
  range of boulders visible to OSIRIS is about 60-300 m. We model the
  trajectories of boulders ejected from the central crater and show that
  their distribution is consistent with most of them being created from
  that crater, similar to the situation on asteroid Eros where most
  of the boulders are believed to originate from Shoemaker crater. We
  evaluate various destruction mechanisms for ejecta blocks and conclude
  that, using current estimates of the number of small asteroids in the
  main belt, destruction by impacts of small (several meters diameter)
  projectiles limits the lifetime of the boulders (and the age of the
  central crater) to a maximum of 300 million years. Since several
  analyses of crater ages and size distributions also come up with
  surprisingly young ages, the size-frequency distribution of small
  main-belt asteroids (below the size currently reached by surveys)
  may warrant to be revisited.

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Title: (21) Lutetia spectrophotometry from Rosetta-OSIRIS images
    and comparison to ground-based observations
Authors: Magrin, S.; La Forgia, F.; Pajola, M.; Lazzarin, M.;
   Massironi, M.; Ferri, F.; da Deppo, V.; Barbieri, C.; Sierks, H.;
   Osiris Team; A'Hearn, M.; Angrilli, F.; Barucci, A.; Bertaux, J. -L.;
   Cremonese, G.; Davidsson, B.; Debei, S.; De Cecco, M.; Fornasier,
   S.; Fulle, M.; Groussin, O.; Gutiérrez, P.; Hviid, S.; Ip, W. -H.;
   Jorda, L.; Keller, H. U.; Knollenberg, J.; Koschny, D.; Kramm, J. R.;
   Kuehrt, E.; Küppers, M.; Lamy, P.; Lara, L. M.; López-Moreno, J. J.;
   Marzari, F.; Michalik, H.; Naletto, G.; Rickman, H.; Rodrigo, R.;
   Sabau, L.; Thomas, N.; Weissman, P. R.; Wenzel, K. -P.
2012P&SS...66...43M    Altcode: 2012P&SS...66...43T
  Here we present some preliminary results on surface variegation found
  on (21) Lutetia from ROSETTA-OSIRIS images acquired on 2010-07-10. The
  spectrophotometry obtained by means of the two cameras NAC and WAC
  (Narrow and Wide Angle Cameras) is consistent with ground based
  observations, and does not show surface diversity above the data error
  bars. The blue and UV images (shortward 500 nm) may, however, indicate
  a variegation of the optical properties of the asteroid surface on
  the Baetica region (Sierks et al., 2011). We also speculate on the
  contribution due to different illumination and to different ground
  properties (composition or, more probably, grain size diversity). In
  particular a correlation with geologic units independently defined by
  Massironi et al. (2012) is evident, suggesting that the variegation
  of the ground optical properties is likely to be real.

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Title: Physical properties of craters on asteroid (21) Lutetia
Authors: Vincent, Jean-Baptiste; Besse, Sébastien; Marchi, Simone;
   Sierks, Holger; Massironi, Matteo; OSIRIS Team; A'Hearn, M.; Angrilli,
   F.; Barbieri, C.; Barucci, A.; Bertaux, J. -L.; Cremonese, G.; Da
   Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.; Fornasier, S.;
   Fulle, M.; Groussin, O.; Gutierrez, P.; Hviid, S. F.; Ip, W. -H.;
   Jorda, L.; Keller, H. U.; Koschny, D.; Knollenberg, J.; Kramm, J. R.;
   Kuehrt, E.; Lamy, P.; Lara, L. M.; Lazzarin, M.; Lopez-Moreno, J. J.;
   Marzari, F.; Michalik, H.; Naletto, G.; Rickman, H.; Rodrigo, R.;
   Sabau, L.; Thomas, N.; Wenzel, K. -P.
2012P&SS...66...79V    Altcode: 2012P&SS...66...79T
  This paper presents an analysis of the physical properties of craters
  on asteroid (21) Lutetia, derived from images acquired by OSIRIS,
  the high-resolution cameras onboard ESA's spacecraft Rosetta. Crater
  morphology on (21) Lutetia fits very well with the general picture
  of what was known for previously visited small bodies, with a typical
  depth to diameter ratio of 0.12. We discuss here the distribution of
  this parameter all across the surface, but also region by region, and
  see how it can vary from one location to another and help to distinguish
  between different geological units. In a later section of the paper
  we study in more details Beatica region where a deep ejecta blanket
  filled most of the craters, and estimate the thickness profile of this
  ejecta based on our analysis of the d/D. We find a good agreement
  with existing scaling laws, and use this to constrain the scale of
  the original event that reshaped the surface around the North pole of
  the asteroid. Finally, we report on the observations of avalanches in
  several crater flanks, and the presence of many asymmetrical craters
  with flow-like features, and discuss the evidence for widespread fine
  material all over the surface.

---------------------------------------------------------
Title: Search for satellites near (21) Lutetia using OSIRIS/Rosetta
    images
Authors: Bertini, Ivano; Sabolo, Walter; Gutierrez, Pedro J.;
   Marzari, Francesco; Snodgrass, Colin; Tubiana, Cecilia; Moissl,
   Richard; Pajola, Maurizio; Lowry, Stephen C.; Barbieri, Cesare; Ferri,
   Francesca; Davidsson, Björn; Sierks, Holger; OSIRIS Team; A'Hearn, M.;
   Angrilli, F.; Barucci, A.; Bertaux, J. -L.; Cremonese, G.; Da Deppo,
   V.; Debei, S.; De Cecco, M.; Fornasier, S.; Fulle, M.; Groussin, O.;
   Hviid, S.; Ip, W. -H.; Jorda, L.; Keller, H. U.; Knollenberg, J.;
   Koschny, D.; Kramm, J. R.; Kuehrt, E.; Küppers, M.; Lamy, P.; Lara,
   L. M.; Lazzarin, M.; Lopez-Moreno, J. J.; Michalik, H.; Naletto, G.;
   Rickman, H.; Rodrigo, R.; Sabau, L.; Thomas, N.; Wenzel, K. -P.
2012P&SS...66...64B    Altcode: 2012P&SS...66...64T
  On 2010 July 10 the ESA Rosetta mission flew by the large asteroid
  (21) Lutetia. One of the scientific goals of the onboard OSIRIS
  instrument was the search for satellites of the asteroid, with more
  than 20 images specifically dedicated to this topic. An observational
  campaign was devised with a selection of filters and exposure times
  tailored to maximize the possibility of detecting small companions
  and determining their bound orbits. Data were analyzed with suitable
  methods to remove cosmic ray hits and known background objects, in
  order to search for persistent detections of potential interesting
  flux sources. We found no unambiguous detections of a satellite larger
  than ∼160m inside the entire sphere of gravitational influence. Our
  search confirmed the absence of bound companions larger than ∼30m
  inside 20 primary radii. These limits are a factor of ∼30 smaller
  than the values reported so far from large ground-based telescopes
  using adaptive optics and from the Hubble Space Telescope.

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Title: ESCAPE : a first step to high resolution solar coronagraphy
    in Antarctica
Authors: Damé, L.; Abe, L.; Faurobert, M.; Fineschi, S.; Kuzin, S.;
   Lamy, P.; Meftah, M.; Vives, S.
2012EAS....55..359D    Altcode:
  The Dome C high plateau is unique for coronagraphic observations: sky
  brightness is reduced, water vapour is low, seeing is excellent and
  continuity of observations on several weeks is possible. ESCAPE (the
  Extreme Solar Coronagraphy Antarctic Program Experiment) will perform
  2-dimensional spectroscopy of the forbidden line of FeXIV at 530.285 nm:
  precise line profile analysis will allow the diagnostic of the nature
  of waves by simultaneous measurements of velocities and intensities in
  the corona. ESCAPE is proposed to Institut Paul-Emile Victor (IPEV)
  for a campaign in 2012-2013 at Dome C/Concordia since all subsystems
  are available in particular thanks to an ESA STARTIGER 2010 R&amp;D
  "Toward a New Generation of Formation Flying Coronagraph". Using
  state-of-the-art technologies developed for Space missions (a
  Three Mirrors Anastigmat telescope, the TMA, a 4 stages Liquid
  Crystal Tunable-filter Polarimeter, the LCTP) allows us to propose
  an automated Coronal Green Line full-field Polarimeter for unique
  observations (waves nature and intensity to address coronal heating)
  with the best possible performances on Earth and for preparing and
  testing the technologies for the next steps in Space. No other site
  would allow such coronagraphic performances (the sky brightness is a
  factor 2 to 4 better than in Hawaï) and with high spatial resolution
  (better than an arcsec is possible).

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Title: High Surface Porosity as the Origin of Emissivity Features
    in Asteroid Spectra
Authors: Vernazza, P.; Delbo, M.; King, P. L.; Izawa, M. R. M.;
   Olofsson, J.; Lamy, P.; Cipriani, F.; Binzel, R. P.; Marchis, F.;
   Merin, B.; Tamanai, A.
2012LPICo1667.6049V    Altcode:
  Here we show that mid-IR emission spectra of asteroids do not only
  carry information about their surface composition but they can also
  help us constraining their surface structure (under-dense versus
  compact surface structure).

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Title: Visible-Wavelength Survey of Jupiter-Family Cometary Nuclei
    as Part of SEPPCoN
Authors: Fernandez, Y. R.; Lowry, S. C.; Meech, K. J.; Laird, R.;
   Fitzsimmons, A.; Snodgrass, C.; Weissman, P. R.; Pittichova, J.;
   Bauer, J. M.; Weaver, H. A.; Lisse, C. M.; A'Hearn, M. F.; Campins,
   H.; Groussin, O.; Kelley, M. S.; Lamy, P. L.; Licandro, J.; Toth,
   I.; Reach, W. T.
2012LPICo1667.6488F    Altcode:
  We present observations of a statistically-significant number of
  Jupiter-family cometary nuclei as part of SEPPCoN (Survey of the
  Ensemble Physical Properties of Cometary Nuclei). We present preliminary
  results on distributions of albedos and shapes.

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Title: The Trojans' Odyssey Space Mission
Authors: Lamy, P.; Vernazza, P.; Groussin, O.; Poncy, J.; Martinot,
   V.; Hinglais, E.; Bell, J.; Cruikshank, D.; Helbert, J.; Marzari,
   F.; Morbidelli, A.; Rosenblatt, P.
2012LPICo1667.6443L    Altcode:
  The proposed Trojans' Odyssey mission is envisioned as a reconnaissance,
  multiple flyby mission aimed at visiting several objects, typically
  five Trojans and one Hilda.

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Title: Asteroid (21) Lutetia: Global and Spatially Resolved
    Photometric Properties
Authors: Lamy, P.; Jorda, L.; Vernazza, P.; Faury, G.
2012LPICo1667.6442L    Altcode:
  We will present results on the global photometric properties of (21)
  Lutetia, as well as spatially resolved properties based on the Hapke
  formalism.

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Title: The Geomorphology of Asteroid 21 Lutetia from In-Situ Imaging
Authors: Jorda, L.; Thomas, N.; Lamy, P.
2012LPICo1667.6406J    Altcode:
  We present an overview of the surface geomorphology of asteroid 21
  Lutetia observed using the high resolution images from OSIRIS, the
  imaging system onboard the European Space Agency’s Rosetta spacecraft.

---------------------------------------------------------
Title: Comet 8P/Tuttle: A portrait of a contact-binary nucleus from
    Hubble and Spitzer space telescopes observations
Authors: Lamy, P.; Toth, I.; Jorda, L.; Groussin, O.; Faury, G.;
   Weaver, H.
2012EGUGA..1410506L    Altcode:
  We detected the nucleus of comet 8P/Tuttle, a nearly-isotropic comet
  (NIC) in a 13.5~yr orbital period, during its 2007--2008 close
  (0.25~AU) Earth encounter with the Planetary Camera 2 of the Hubble
  Space Telescope(HST on 10-11 December 2007 and with the infrared
  camera (MIPS) of the Spitzer Space Telescope (SST) on 22-23 June 2008,
  sampling the rotational period of the nucleus. We determined a synodic
  rotational period of 11.40 +/-0.12 h and, by combining with the radar
  observations of Harmon et al. (2010), a sidereal rotation period
  of 11.444 +/-0.001h. The visible and thermal light curve exhibit a
  complex shape best modeled by a contact-binary as evidenced by the radar
  observations. By combining these light curves and adding a constraint on
  the thermal inertia coming from millimetric observations at the Plateau
  de Bure Observatory, we determined the shape and size of the binary
  system approximated by two spheres in contact with respective radius
  of 2.56 and 1.1 km, a common albedo in the range 0.04 to 0.054 and
  a linear phase coefficient in the range 0.033 to 0.04 mag/deg. These
  results suggest a strong similarity of the properties of the nuclei
  of ecliptic and nearly-isotropic comets. We found that the shape model
  resulting from the radar observations is incompatible with both the HST
  and SST observations. A partial agreement could be obtained by assuming
  very different albedos of the two components, in a ratio of at least 5.

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Title: Trojans' Odyssey: Unveiling the early history of the Solar
    System
Authors: Lamy, Philippe; Vernazza, Pierre; Poncy, Joel; Martinot,
   Vincent; Hinglais, Emmanuel; Canalias, Elisabet; Bell, Jim;
   Cruikshank, Dale; Groussin, Olivier; Helbert, Joern; Marzari,
   Francesco; Morbidelli, Alessandro; Rosenblatt, Pascal; Sierks, Holger
2012ExA....33..685L    Altcode: 2011ExA...tmp...71L; 2011ExA...tmp..114L; 2011ExA...tmp...92L
  In our present understanding of the Solar System, small bodies
  (asteroids, Jupiter Trojans, comets and TNOs) are the most
  direct remnants of the original building blocks that formed the
  planets. Jupiter Trojan and Hilda asteroids are small primitive bodies
  located beyond the `snow line', around respectively the L<SUB>4</SUB>
  and L<SUB>5</SUB> Lagrange points of Jupiter at ∼5.2 AU (Trojans) and
  in the 2:3 mean-motion resonance with Jupiter near 3.9 AU (Hildas). They
  are at the crux of several outstanding and still conflicting issues
  regarding the formation and evolution of the Solar System. They hold
  the potential to unlock the answers to fundamental questions about
  planetary migration, the late heavy bombardment, the formation of the
  Jovian system, the origin and evolution of trans-neptunian objects,
  and the delivery of water and organics to the inner planets. The
  proposed Trojans' Odyssey mission is envisioned as a reconnaissance,
  multiple flyby mission aimed at visiting several objects, typically five
  Trojans and one Hilda. It will attempt exploring both large and small
  objects and sampling those with any known differences in photometric
  properties. The orbital strategy consists in a direct trajectory to one
  of the Trojan swarms. By carefully choosing the aphelion of the orbit
  (typically 5.3 AU), the trajectory will offer a long arc in the swarm
  thus maximizing the number of flybys. Initial gravity assists from
  Venus and Earth will help reducing the cruise time as well as the ΔV
  needed for injection thus offering enough capacity to navigate among
  Trojans. This solution further opens the unique possibility to flyby a
  Hilda asteroid when leaving the Trojan swarm. During the cruise phase,
  a Main Belt Asteroid could be targeted if requiring a modest ΔV. The
  specific science objectives of the mission will be best achieved with a
  payload that will perform high-resolution panchromatic and multispectral
  imaging, thermal-infrared imaging/ radiometry, near- and mid-infrared
  spectroscopy, and radio science/mass determination. The total mass
  of the payload amounts to 50 kg (including margins). The spacecraft
  is in the class of Mars-Express or a down-scaled version of Jupiter
  Ganymede Orbiter. It will have a dry mass of 1200 kg, a total mass at
  launch of 3070 kg and a ΔV capability of 700 m/s (after having reached
  the first Trojan) and can be launched by a Soyuz rocket. The mission
  operations concept (ground segment) and science operations are typical
  of a planetary mission as successfully implemented by ESA during, for
  instance, the recent flybys of Main Belt asteroids Steins and Lutetia.

---------------------------------------------------------
Title: The interaction between coronal mass ejections and streamers
    as viewed by LASCO over 15 years
Authors: Floyd, O.; Lamy, P.; Llebaria, A.
2012EGUGA..14.9899F    Altcode:
  The question of the relationship of coronal mass ejections (CMEs)
  to streamers dates back to the early observations of CMEs with space
  coronagraphs and subsequent efforts to understand their origin. Whereas
  the mass and kinetic energy losses of CMEs are insignificant in
  the corona, they are considered a key player as a means to remove
  magnetic flux and helicity that would otherwise build up in the
  corona. How this may work essentially boils down to the nature of the
  CME-streamer interaction i.e., as to whether CMEs respond passively
  or contribute dynamically to the coronal field restructuring. We are
  reconsidering this question on the basis of high resolution synoptic
  maps at 3 Rsun constructed from the LASCO-C2 images of the corona
  over 15 years (1996-2010) thus encompassing cycle 23 and the rising
  phase of cycle 24. During that period, our ARTEMIS II catalog of
  LASCO CMEs reports 21394 events and studying their interaction with
  the streamer belt requires an automated procedure. For this purpose,
  we consider that streamers are prominently one dimensional objects,
  manifesting the boundary between regions of opposite magnetic
  polarities that can be represented by the line of maximum radiance
  along them. As such, streamers are defined as ridges on the synoptic
  maps and an efficient way to detect these ridges consist in applying
  a watershed filter. Then for each CME (which appears as a vertical
  streak on the synoptic maps), we detect the streamer ridges present
  before and after its occurence all along its latitudinal extent. The
  CME-streamer interaction is then quantified in terms of geometric
  changes (appearance/disappearance or displacement of the streamer)
  and photometric changes (brightening/dimming of the streamer). We
  will present statistical data on these interactions for the 1996-2010
  time period.

---------------------------------------------------------
Title: A Global Two-temperature Corona and Inner Heliosphere Model:
    A Comprehensive Validation Study
Authors: Jin, M.; Manchester, W. B.; van der Holst, B.; Gruesbeck,
   J. R.; Frazin, R. A.; Landi, E.; Vasquez, A. M.; Lamy, P. L.; Llebaria,
   A.; Fedorov, A.; Toth, G.; Gombosi, T. I.
2012ApJ...745....6J    Altcode:
  The recent solar minimum with very low activity provides us a unique
  opportunity for validating solar wind models. During CR2077 (2008
  November 20 through December 17), the number of sunspots was near
  the absolute minimum of solar cycle 23. For this solar rotation,
  we perform a multi-spacecraft validation study for the recently
  developed three-dimensional, two-temperature, Alfvén-wave-driven
  global solar wind model (a component within the Space Weather Modeling
  Framework). By using in situ observations from the Solar Terrestrial
  Relations Observatory (STEREO) A and B, Advanced Composition Explorer
  (ACE), and Venus Express, we compare the observed proton state (density,
  temperature, and velocity) and magnetic field of the heliosphere with
  that predicted by the model. Near the Sun, we validate the numerical
  model with the electron density obtained from the solar rotational
  tomography of Solar and Heliospheric Observatory/Large Angle and
  Spectrometric Coronagraph C2 data in the range of 2.4 to 6 solar
  radii. Electron temperature and density are determined from differential
  emission measure tomography (DEMT) of STEREO A and B Extreme Ultraviolet
  Imager data in the range of 1.035 to 1.225 solar radii. The electron
  density and temperature derived from the Hinode/Extreme Ultraviolet
  Imaging Spectrometer data are also used to compare with the DEMT as
  well as the model output. Moreover, for the first time, we compare
  ionic charge states of carbon, oxygen, silicon, and iron observed in
  situ with the ACE/Solar Wind Ion Composition Spectrometer with those
  predicted by our model. The validation results suggest that most of the
  model outputs for CR2077 can fit the observations very well. Based on
  this encouraging result, we therefore expect great improvement for the
  future modeling of coronal mass ejections (CMEs) and CME-driven shocks.

---------------------------------------------------------
Title: The Evolution of Plasma Parameters on a Coronal Source Surface
    at 2.3 R <SUB>⊙</SUB> during Solar Minimum
Authors: Strachan, L.; Panasyuk, A. V.; Kohl, J. L.; Lamy, P.
2012ApJ...745...51S    Altcode: 2011arXiv1111.1206S
  We analyze data from the Solar and Heliospheric Observatory to
  produce global maps of coronal outflow velocities and densities
  in the regions where the solar wind is undergoing acceleration. The
  maps use UV and white light coronal data obtained from the Ultraviolet
  Coronagraph Spectrometer and the Large Angle Spectroscopic Coronagraph,
  respectively, and a Doppler dimming analysis to determine the mean
  outflow velocities. The outflow velocities are defined on a sphere at
  2.3 R <SUB>⊙</SUB> from Sun-center and are organized by Carrington
  Rotations during the solar minimum period at the start of solar cycle
  23. We use the outflow velocity and density maps to show that while the
  solar minimum corona is relatively stable during its early stages, the
  shrinkage of the north polar hole in the later stages leads to changes
  in both the global areal expansion of the coronal hole and the derived
  internal flux tube expansion factors of the solar wind. The polar hole
  areal expansion factor and the flux tube expansion factors (between
  the coronal base and 2.3 R <SUB>⊙</SUB>) start out as super-radial
  but then they become more nearly radial as the corona progresses away
  from solar minimum. The results also support the idea that the largest
  flux tube expansion factors are located near the coronal hole/streamer
  interface, at least during the deepest part of the solar minimum period.

---------------------------------------------------------
Title: Asteroid (21) Lutetia as a remnant of Earth’s precursor
    planetesimals
Authors: Vernazza, P.; Lamy, P.; Groussin, O.; Hiroi, T.; Jorda, L.;
   King, P. L.; Izawa, M. R. M.; Marchis, F.; Birlan, M.; Brunetto, R.
2011Icar..216..650V    Altcode:
  Isotopic and chemical compositions of meteorites, coupled with dynamical
  simulations, suggest that the main belt of asteroids between Mars and
  Jupiter contains objects formed in situ as well as a population of
  interlopers. These interlopers are predicted to include the building
  blocks of the terrestrial planets as well as objects that formed
  beyond Neptune (Bottke et al. 2006, Levison et al. 2009, Walsh et
  al. 2011). Here we report that the main belt asteroid (21) Lutetia -
  encountered by the Rosetta spacecraft in July 2010 - has spectral (from
  0.3 to 25 μm) and physical (albedo, density) properties quantitatively
  similar to the class of meteorites known as enstatite chondrites. The
  chemical and isotopic compositions of these chondrites indicate that
  they were an important component of the formation of Earth and other
  terrestrial planets. This meteoritic association implies that Lutetia
  is a member of a small population of planetesimals that formed in
  the terrestrial planet region and that has been scattered in the
  main belt by emerging protoplanets (Bottke et al. 2006) and/or by the
  migration of Jupiter (Walsh et al. 2011) early in its history. Lutetia,
  along with a few other main-belt asteroids, may contains part of the
  long-sought precursor material (or closely related materials) from
  which the terrestrial planets accreted.

---------------------------------------------------------
Title: The cosmic dust analyser onboard cassini: ten years of
    discoveries
Authors: Srama, R.; Kempf, S.; Moragas-Klostermeyer, G.; Altobelli,
   N.; Auer, S.; Beckmann, U.; Bugiel, S.; Burton, M.; Economomou, T.;
   Fechtig, H.; Fiege, K.; Green, S. F.; Grande, M.; Havnes, O.; Hillier,
   J. K.; Helfert, S.; Horanyi, M.; Hsu, S.; Igenbergs, E.; Jessberger,
   E. K.; Johnson, T. V.; Khalisi, E.; Krüger, H.; Matt, G.; Mocker, A.;
   Lamy, P.; Linkert, G.; Lura, F.; Möhlmann, D.; Morfill, G. E.; Otto,
   K.; Postberg, F.; Roy, M.; Schmidt, J.; Schwehm, G. H.; Spahn, F.;
   Sterken, V.; Svestka, J.; Tschernjawski, V.; Grün, E.; Röser, H. -P.
2011CEAS....2....3S    Altcode: 2018arXiv180204772S
  The interplanetary space probe Cassini/Huygens reached Saturn in July
  2004 after 7 years of cruise phase. The German cosmic dust analyser
  (CDA) was developed under the leadership of the Max Planck Institute
  for Nuclear Physics in Heidelberg under the support of the DLR
  e.V. This instrument measures the interplanetary, interstellar and
  planetary dust in our solar system since 1999 and provided unique
  discoveries. In 1999, CDA detected interstellar dust in the inner
  solar system followed by the detection of electrical charges of
  interplanetary dust grains during the cruise phase between Earth and
  Jupiter. The instrument determined the composition of interplanetary
  dust and the nanometre-sized dust streams originating from Jupiter's
  moon Io. During the approach to Saturn in 2004, similar streams of
  submicron grains with speeds in the order of 100 km/s were detected
  from Saturn's inner and outer ring system and are released to the
  interplanetary magnetic field. Since 2004 CDA measured more than one
  million dust impacts characterising the dust environment of Saturn. The
  instrument is one of the three experiments which discovered the active
  ice geysers located at the south pole of Saturn's moon Enceladus in
  2005. Later, a detailed compositional analysis of the water ice grains
  in Saturn's E ring system led to the discovery of large reservoirs of
  liquid water (oceans) below the icy crust of Enceladus. Finally, the
  determination of the dust-magnetosphere interaction and the discovery
  of the extended E ring (at least twice as large as predicted) allowed
  the definition of a dynamical dust model of Saturn's E ring describing
  the observed properties. This paper summarizes the discoveries of a
  10-year story of success based on reliable measurements with the most
  advanced dust detector flown in space until today. This paper focuses
  on cruise results and findings achieved at Saturn with a focus on flux
  and density measurements. CDA discoveries related to the detailed dust
  stream dynamics, E ring dynamics, its vertical profile and E ring
  compositional analysis are published elsewhere (see Hus et al. in
  AIP Conference Proccedings 1216:510-513, 2010; Hsu et al. in Icarus
  206:653-661, 2010; Kempf et al. in Icarus 193:420, 2008; 206(2):446,
  2010; Postberg et al. in Icarus 193(2):438, 2008; Nature 459:1098,
  2009; Nature, 2011, doi: 10.1038/nature10175).

---------------------------------------------------------
Title: Comparison of Velocity, Density, Temperature, and Mass Flux
    Results with Solar Coronal Models
Authors: Strachan, L.; Cranmer, S. R.; Panasyuk, A.; Kohl, J. L.;
   Lamy, P. L.
2011AGUFMSH53C..07S    Altcode:
  We have recently computed a series of global maps of plasma parameters
  in the extended corona using data from the Solar and Heliospheric
  Observatory (SOHO). The synoptic maps of velocity, density, temperature,
  and mass flux were derived from UV and white light coronal data
  obtained from the Ultraviolet Coronagraph Spectrometer (UVCS) and
  the Large Angle Spectroscopic Coronagraph (LASCO). The parameters
  are defined on a sphere at 2.3~ R<SUB>⊙</SUB> from Sun-center and
  are organized by Carrington Rotations during the 1996 -- 1998 solar
  minimum for Solar Cycle 23. The data imply that there are large flux
  tube expansion factors near the coronal hole/streamer boundaries,
  but these factors change significantly as the corona evolves from
  minimum to the rising phase. We compare these data to an independently
  developed theoretical model that includes damping and acceleration
  by Alfven waves in the corona (see Cranmer et al. 2007, ApJS, 171,
  520). The data set will be extended in the future and it will be used
  for constraining other theoretical models of the corona and solar wind.

---------------------------------------------------------
Title: The helium shells of HeI and HeII at solar minimum: New
    results from eclipse flash spectra of 2008- 2010
Authors: Bazin, C.; Koutchmy, S.; Lamy, P.
2011sf2a.conf..203B    Altcode:
  Flash spectra taken at high frame rate during the total solar
  eclipse of August 1st 2008 in Siberia and during the July 11th 2010
  in French Polynesia are compared in the context of the quiet Sun near
  the minimum of activity. They both reveal the weak Paschen α 468.6
  nm ionized helium line, seen as a helium shell in layers up to the
  8 Mm heights. The preliminary evaluated effective height of the He
  I 4713 shell is 1.8 Mm and it is approximately 2.0 Mm for the He II
  4686 emissions outside polar regions. These lines can be measured
  only in eclipse conditions, when the parasitic scattered light is
  negligible for very low solar fluxes corresponding to the coronal
  levels. Many faint lines are also seen in emission such as Ba +, Ti +,
  Fe +, but with a much lower radial extension. They were observed to be
  superposed to F-lines when defining the solar limb using the continuum
  background. A cartoon is proposed to describe the structuration of
  these low layers and to illustrate the contribution of the magnetic
  field. These observations are important new insights for understanding
  (i) the magnetic field inference in the very low layers of the solar
  transition region and (ii) the ionisation mechanisms producing the
  big jump of the temperature towards the corona, including the source
  of heating.

---------------------------------------------------------
Title: Observations of the White Light Corona from Solar Orbiter
    and Solar Probe Plus
Authors: Howard, R. A.; Thernisien, A. F.; Vourlidas, A.; Plunkett,
   S. P.; Korendyke, C. M.; Sheeley, N. R.; Morrill, J. S.; Socker,
   D. G.; Linton, M. G.; Liewer, P. C.; De Jong, E. M.; Velli, M. M.;
   Mikic, Z.; Bothmer, V.; Lamy, P. L.
2011AGUFMSH43F..06H    Altcode:
  The SoloHI instrument on Solar Orbiter and the WISPR instrument on Solar
  Probe+ will make white light coronagraphic images of the corona as the
  two spacecraft orbit the Sun. The minimum perihelia for Solar Orbiter
  is about 60 Rsun and for SP+ is 9.5 Rsun. The wide field of view of the
  WISPR instrument (about 105 degrees radially) corresponds to viewing
  the corona from 2.2 Rsun to 20 Rsun. Thus the entire Thomson hemisphere
  is contained within the telescope's field and we need to think of
  the instrument as being a traditional remote sensing instrument and
  then transitioning to a local in-situ instrument. The local behavior
  derives from the fact that the maximum Thomson scattering will favor
  the electron plasma close to the spacecraft - exactly what the in-situ
  instruments will be sampling. SoloHI and WISPR will also observe
  scattered light from dust in the inner heliosphere, which will be an
  entirely new spatial regime for dust observations from a coronagraph,
  which we assume to arise from dust in the general neighborhood of about
  half way between the observer and the Sun. As the dust grains approach
  the Sun, they evaporate and do not contribute to the scattering. A
  dust free zone has been postulated to exist somewhere inside of 5 Rsun
  where all dust is evaporated, but this has never been observed. The
  radial position where the evaporation occurs will depend on the
  precise molecular composition of the individual grains. The orbital
  plane of Solar Orbiter will gradually increase up to about 35 degrees,
  enabling a very different view through the zodiacal dust cloud to test
  the models generated from in-ecliptic observations. In this paper we
  will explore some of the issues associated with the observation of
  the dust and will present a simple model to explore the sensitivity
  of the instrument to observe such evaporations.

---------------------------------------------------------
Title: The Trojans' Odyssey space mission
Authors: Lamy, P.; Vernazza, P.; Groussin, O.; Poncy, J.; Martinot,
   V.; Hinglais, E.; Bell, J.; Cruikshank, D.; Helbert, J.; Marzari,
   F.; Morbidelli, A.; Rosenblatt, P.
2011epsc.conf..703L    Altcode: 2011DPS....43..703L
  In our present understanding of the Solar System, small bodies
  (asteroids, Jupiter Trojans, comets and TNOs) are the most
  direct remnants of the original building blocks that formed the
  planets. Jupiter Trojan and Hilda asteroids are small primitive
  bodies located beyond the "snow line", around respectively the L4
  and L5 Lagrange points of Jupiter at 5.2 AU (Trojans) and in the
  2:3 mean-motion resonance with Jupiter near 3.9 AU (Hildas). They
  are at the crux of several outstanding and still conflicting issues
  regarding the formation and evolution of the Solar System. They hold
  the potential to unlock the answers to fundamental questions about
  planetary migration, the late heavy bombardment, the formation of the
  Jovian system, the origin and evolution of trans-neptunian objects,
  and the delivery of water and organics to the inner planets. The
  proposed Trojans' Odyssey mission is envisioned as a reconnaissance,
  multiple flyby mission aimed at visiting several objects, typically five
  Trojans and one Hilda. It will attempt exploring both large and small
  objects and sampling those with any known differences in photometric
  properties. The orbital strategy consists in a direct trajectory to one
  of the Trojan swarms. By carefully choosing the aphelion of the orbit
  (typically 5.3 AU), the trajectory will offer a long arc in the swarm
  thus maximizing the number of flybys. Initial gravity assists from Venus
  and Earth will help reducing the cruise to 7 years as well as the ?V
  needed for injection thus offering enough capacity to navigate among
  Trojans. This solution further opens the unique possibility to flyby a
  Hilda asteroid when leaving the Trojan swarm. During the cruise phase,
  a Main Belt Asteroid could be targeted if requiring a modest ?V. The
  specific science objectives of the mission will be best achieved with a
  payload that will perform high-resolution panchromatic and multispectral
  imaging, thermal-infrared imaging/ radiometry, near- and mid-infrared
  spectroscopy, and radio science/mass determination. The total mass
  of the payload amounts to 50 kg (including margins). The spacecraft
  is in the class of Mars-Express or a down-scaled version of Jupiter
  Ganymede Orbiter. It will have a dry mass of 1200 kg, a total mass at
  launch of 3070 kg and a V capability of 700 m/sec (after having reached
  the first Trojan) and can be launched by a Soyuz rocket. The mission
  operations concept (ground segment) and science operations are typical
  of a planetary mission as successfully implemented by ESA during, for
  instance, the recent flybys of Main Belt asteroids Steins and Lutetia.

---------------------------------------------------------
Title: THERMAP: a mid-infrared spectro-imager based on an uncooled
    micro-bolometer for the Marco Polo R mission.
Authors: Brageot, E.; Groussin, O.; Lamy, P.; Reynaud, J. L.;
   Fargant, G.
2011epsc.conf..129B    Altcode: 2011DPS....43..129B
  We report on an on-going feasibility study of a midinfrared (8-18 μm)
  spectro-imager for the Marco Polo R mission (THERMAP). Based on the
  recent development of uncooled micro-bolometer technology, we can now
  use these detectors for planetary missions. We present our results
  on using this detector to perform calibrated radiometric images,
  and a preliminary assessment of its performances for spectroscopic
  measurements of a Near Earth Asteroid (NEA).

---------------------------------------------------------
Title: Shape and Physical Properties of Asteroid (21) Lutetia from
    OSIRIS Images
Authors: Jorda, L.; Gaskell, R.; Lamy, P.; Kaasalainen, M.; Groussin,
   O.; Faury, G.; Gutierrez, P.; Sabolo, W.; Hviid, S.
2011epsc.conf..776J    Altcode: 2011DPS....43..776J
  The Rosetta spacecraft of the European Space Agency flew by asteroid
  (21) Lutetia on July, 10, 2010 on its way to its final target, comet
  67P/Churyumov- Gerasimenko. A total of 460 images has been acquired
  during the flyby with the narrow (NAC) and wide (WAC) angle cameras
  of the OSIRIS instrument, the NAC pixel scale reaching a minimum
  value of 60 m at closest approach. Several filters have been used,
  covering a wavelength range from the far UV (0.25 μm) to the end of
  the visible spectrum (1.0 μm). The phase angle went through the range
  11°-0°-160°, the spacecraft reaching opposition 18 min before closest
  approach. We will report on the calculation of the threedimensional
  high-resolution global shape model of (21) Lutetia using two techniques:
  stereophotoclinometry for the regions observed by OSIRIS, complemented
  by inversion of photometric light curves and adaptive optics profiles
  for the rest of the surface. This allows us to retrieve the physical
  properties of this object: volume, moments of inertia, gravity field,
  local gravitational slopes and rotational parameters. The density is
  calculated using the mass measured by the radio science experiment (RSI)
  on board Rosetta. We will further discuss quantitatively the properties
  of the main geo-morphological features observed at the surface.

---------------------------------------------------------
Title: Images of Asteroid 21 Lutetia: A Remnant Planetesimal from
    the Early Solar System
Authors: Sierks, H.; Lamy, P.; Barbieri, C.; Koschny, D.; Rickman, H.;
   Rodrigo, R.; A'Hearn, M. F.; Angrilli, F.; Barucci, M. A.; Bertaux,
   J. -L.; Bertini, I.; Besse, S.; Carry, B.; Cremonese, G.; Da Deppo,
   V.; Davidsson, B.; Debei, S.; De Cecco, M.; De Leon, J.; Ferri, F.;
   Fornasier, S.; Fulle, M.; Hviid, S. F.; Gaskell, R. W.; Groussin, O.;
   Gutierrez, P.; Ip, W.; Jorda, L.; Kaasalainen, M.; Keller, H. U.;
   Knollenberg, J.; Kramm, R.; Kührt, E.; Küppers, M.; Lara, L.;
   Lazzarin, M.; Leyrat, C.; Moreno, J. J. Lopez; Magrin, S.; Marchi,
   S.; Marzari, F.; Massironi, M.; Michalik, H.; Moissl, R.; Naletto,
   G.; Preusker, F.; Sabau, L.; Sabolo, W.; Scholten, F.; Snodgrass,
   C.; Thomas, N.; Tubiana, C.; Vernazza, P.; Vincent, J. -B.; Wenzel,
   K. -P.; Andert, T.; Pätzold, M.; Weiss, B. P.
2011Sci...334..487S    Altcode:
  Images obtained by the Optical, Spectroscopic, and Infrared Remote
  Imaging System (OSIRIS) cameras onboard the Rosetta spacecraft
  reveal that asteroid 21 Lutetia has a complex geology and one of
  the highest asteroid densities measured so far, 3.4 ± 0.3 grams per
  cubic centimeter. The north pole region is covered by a thick layer of
  regolith, which is seen to flow in major landslides associated with
  albedo variation. Its geologically complex surface, ancient surface
  age, and high density suggest that Lutetia is most likely a primordial
  planetesimal. This contrasts with smaller asteroids visited by previous
  spacecraft, which are probably shattered bodies, fragments of larger
  parents, or reaccumulated rubble piles.

---------------------------------------------------------
Title: Shape reconstruction of irregular bodies with multiple
    complementary data sources
Authors: Kaasalainen, M.; Viikinkoski, M.; Carry, B.; Durech, J.;
   Lamy, P.; Jorda, L.; Marchis, F.; Hestroffer, D.
2011epsc.conf..416K    Altcode: 2011DPS....43..416K
  Irregularly shaped bodies with at most partial in situ data are a
  particular challenge for shape reconstruction and mapping. We have
  created an inversion algorithm and software package for complementary
  data sources, with which it is possible to create shape and spin
  models with feature details even when only groundbased data are
  available. The procedure uses photometry, adaptive optics or other
  images, occultation timings, and interferometry as main data sources,
  and we are extending it to include range-Doppler radar and thermal
  infrared data as well. The data sources are described as generalized
  projections in various observable spaces [2], which allows their uniform
  handling with essentially the same techniques, making the addition of
  new data sources inexpensive in terms of computation time or software
  development. We present a generally applicable shape support that can be
  automatically used for all surface types, including strongly nonconvex
  or non-starlike shapes. New models of Kleopatra (from photometry,
  adaptive optics, and interferometry) and Hermione are examples of this
  approach. When using adaptive optics images, the main information from
  these is extracted from the limb and terminator contours that can be
  determined much more accurately than the image pixel brightnesses that
  inevitably contain large errors for most targets. We have shown that the
  contours yield a wealth of information independent of the scattering
  properties of the surface [3]. Their use also facilitates a very fast
  and robustly converging algorithm. An important concept in the inversion
  is the optimal weighting of the various data modes. We have developed
  a mathematicallly rigorous scheme for this purpose. The resulting
  maximum compatibility estimate [3], a multimodal generalization of
  the maximum likelihood estimate, ensures that the actual information
  content of each source is properly taken into account, and that the
  resolution scale of the ensuing model can be reliably estimated. We
  have applied our procedure to several asteroids, and the ground truth
  from the Rosetta/Lutetia flyby confirmed the ability of the approach
  to recover shape details [1] (see also Carry et al., this meeting). We
  have created a general flyby-version of the procedure to construct
  full models of planetary targets for which probe images are only
  available of a part of the surface (a typical setup for many planetary
  missions). We have successfully combined flyby images with photometry
  (Steins [4]) and adaptive optics images (Lutetia); the portion of
  the surface accurately determined by the flyby constrains the shape
  solution of the "dark side" efficiently.

---------------------------------------------------------
Title: Asteroids (21) Lutetia and (2867) Steins: same origin but
    different evolution ?
Authors: Lamy, P.; Vernazza, P.; Groussin, O.; Jorda, L.
2011epsc.conf..699L    Altcode: 2011DPS....43..699L
  Asteroids (21) Lutetia and (2867) Steins which have recently been
  visited by the Rosetta spacecraft of the European Space Agency are both
  members of very small populationss of bodies among the vast majority
  of asteroids. After having been the archetype of the M taxonomy class,
  Lutetia is now an Xc type (DeMeo et al. 2009). Steins is classified as
  an igneous E-type asteroids, more precisely in the new Xe subclass (De-
  Meo et al. 2009) which contains only 7 known members. The composition
  and henceforth origin of asteroids rely on their association to
  meteorites if proper analogs based on visible, NIR and MIR reflectances
  can be identified. Following the most recent spectroscopic works,
  the association of Lutetia to enstatite chondrites appears robust
  (Vernazza et al. 2011). The case of Steins is less clear but aubrite
  meteorites are favored although several features in its spectrum still
  poses problems and we actually may not have in our present meteorite
  collections the proper analog (Clark et al. 2004). The trend of these
  associations with meteorites which represent a reduced, volatile-poor,
  anhydrous end-member of early solar system materials (Rubin 1997,
  Scott 2007) thought to have formed in the inner region of the solar
  nebula, near the proto-Sun implies that neither Lutetia nor Steins
  formed at their present location in the asteroid belt and are probably
  part of the population of interlopers. The dynamical mechnanism that
  transported them from the inner solar system to the main belt is likely
  to be similar to the one explaining the origin of iron meteorites as
  remnants of differentiated planetesimals formed in the terrestrial
  planet region (Bottke et al. 2006). Extended dynamical simulations
  reveal that, at the time where terrestrial accretion was ongoing, a
  small fraction (&lt;2%) of the planetesimals residing in the 0.5-1.5
  AU region were scattered out by emerging protoplanets and achieved
  main-belt orbits, thus becoming dynamically indistinguishable from
  the rest of the main-belt population. However based on the physical
  properties derived from the recent flybys, Lutetia and Steins have
  followed very different evolutions. With a density of 3.4 g/cm3,
  Lutetia appears as a primordial planetesimal having suffered at most
  minimal shattering from the largest impacts. On the contrary, the
  shape of Steins suggests complete restructuring in a rubble-pile as
  a consequence of the catastrophic disruption of its parent body.

---------------------------------------------------------
Title: Asteroids (21) Lutetia: global and spatially resolved
    photometric properties
Authors: Faury, G.; Lamy, P.; Vernazza, P.; Jorda, L.; Toth, I.
2011epsc.conf..759F    Altcode: 2011DPS....43..759F
  Asteroids (21) Lutetia has recently been visited by the Rosetta
  spacecraft of the European Space Agency and imaged by its Rosetta
  narrow (NAC) and wide (WAC) angle cameras. The accurate photometric
  analysis of the images requires utmost care due to several instrumental
  problems, the most severe and complex to handle being the presence of
  optical ghosts which result from multiple reflections on the two filters
  inserted in the optical beam and on the thick window which protects the
  CCD detector from cosmic ray impacts. These ghosts prominently appears
  as either slighlty defocused images offset from the primary images or
  large round or elliptical halos. The appearance, the location and the
  radiance of each individual ghost depends upon the optical configuration
  (selected filters) and on the image itself so that no general model
  can be proposed. Consequently, a case-by-case approach must be adopted
  which requires a long and tedious work where each ghost is individually
  parametrized according to its specific geometry (defocused offset image
  or halo) and iteratively fitted to the original image. The procedure
  has been successfully applied to all NAC and WAC images and works
  extremely well with residuals and sometime artifacts at insignificant
  levels. Both NAC and WAC have further been recalibrated using the most
  recent observations of stellar calibrators VEGA and the solar analog
  16 Cyg B allowing to correct the quantum efficiency response of the
  two CCD and the throughput for all channels (i.e., filters). We will
  present results on the global photometric properties of (21) Lutetia,
  albedo, phase function and spectral reflectivity as well as spatially
  resolved properties based on a novel method developed in the space of
  the facets representing the three-dimensional shape of the body. This
  method successfully implemented in the cases of the nucleus of comet
  9P/Tempel 2 and of asteroid (2867) Steins (Spjuth et al. 2011) has the
  advantage of automatically tracking the same local surface element on
  a series of images. The analysis proceeds with the determination of the
  global Hapke and other standard photometric parameters as well as their
  two-dimensional variations across the surface. This allows defining,
  in the body-fixed reference frame, "high residual regions" (HRRs) which
  correspond to significant relative differences between the observed
  and modeled photometric parameters such as the singlescattering albedo
  (SSA), the mean roughness slope angle, and the reflectivity gradient.

---------------------------------------------------------
Title: Plateau de Bure observations of the methanol in 103P/Hartley
Authors: Boissier, J.; Bockelée-Morvan, D.; Biver, N.; Crovisier, J.;
   Colom, P.; Lellouch, E.; Moreno, R.; Groussin, O.; Jorda, L.; Lamy, P.
2011epsc.conf..985B    Altcode: 2011DPS....43..985B
  The comet 103P/Hartley 2 made a close approach to the Earth in October
  2010, down to a distance of 0.12 AU. In early November, the Deep
  Impact spacecraft performed a flyby of the comet, in the framework
  of its extended mission Epoxi [1]. It has been the target of various
  observing campaigns at all wavelengths involving ground- and space-based
  observatories [2]. We present here the results of observations performed
  with the IRAM Plateau de Bure. We observed the emission of several
  methanol lines from which we built the methanol rotation diagram and
  measured the rotational temperature in the coma. The interferometric
  maps have a spatial resolution of few arcseconds, corresponding to
  few hundred kilometers. Combined to single dish observations these
  data allow the measurement of the temperature profile in the coma. In
  addition, other coma properties can be investigateded from our data
  set such as the origin of methanol in the coma, the coma structure
  and its time variability.

---------------------------------------------------------
Title: Asteroid 21 Lutetia: Low Mass, High Density
Authors: Pätzold, M.; Andert, T. P.; Asmar, S. W.; Anderson, J. D.;
   Barriot, J. -P.; Bird, M. K.; Häusler, B.; Hahn, M.; Tellmann, S.;
   Sierks, H.; Lamy, P.; Weiss, B. P.
2011Sci...334..491P    Altcode:
  Asteroid 21 Lutetia was approached by the Rosetta spacecraft on 10 July
  2010. The additional Doppler shift of the spacecraft radio signals
  imposed by 21 Lutetia’s gravitational perturbation on the flyby
  trajectory were used to determine the mass of the asteroid. Calibrating
  and correcting for all Doppler contributions not associated with
  Lutetia, a least-squares fit to the residual frequency observations
  from 4 hours before to 6 hours after closest approach yields a mass
  of (1.700 ± 0.017) × 10<SUP>18</SUP> kilograms. Using the volume
  model of Lutetia determined by the Rosetta Optical, Spectroscopic,
  and Infrared Remote Imaging System (OSIRIS) camera, the bulk density,
  an important parameter for clues to its composition and interior, is
  (3.4 ± 0.3) × 10<SUP>3</SUP> kilograms per cubic meter.

---------------------------------------------------------
Title: A new 3D reconstruction method of small solar system bodies
Authors: Capanna, C.; Jorda, L.; Lamy, P.; Gesquiere, G.
2011epsc.conf..945C    Altcode: 2011DPS....43..945C
  The 3D reconstruction of small solar system bodies consitutes an
  essential step toward understanding and interpreting their physical
  and geological properties. We propose a new reconstruction method by
  photoclinometry based on the minimization of the chisquare difference
  between observed and synthetic images by deformation of a 3D triangular
  mesh. This method has been tested on images of the two asteroids
  (2867) Steins and (21) Lutetia observed during ESA's ROSETTA mission,
  and it will be applied to elaborate digital terrain models from images
  of the asteroid (4) Vesta, the target of NASA's DAWN spacecraft.

---------------------------------------------------------
Title: A Global Two-Temperature Corona and Inner Heliosphere Model:
    A Validation Study
Authors: Jin, Meng; Manchester, W. B.; van der Holst, B.; Gruesbeck,
   J.; Frazin, R. A.; Vasquez, A. M.; Lamy, P. L.; Llebaria, A.; Fedorov,
   A.; Toth, G.; Gombosi, T. I.
2011shin.confE..12J    Altcode:
  The recent solar minimum with very low activity provides us a unique
  opportunity for validating solar wind models. During CR2077 (2008,
  November 20 through December 17), the sunspots number reaches the
  absolute minimum of solar cycle 23. For this solar rotation, we
  perform a multi-spacecraft validation study for the recently developed
  three-dimensional, two-temperature, Alfven-wave-driven global solar wind
  model (a component within the Space Weather Modeling Framework). By
  using in situ observations from STEREO A and B, ACE/WIND and Venus
  Express, we compare the observed proton state (density, temperature and
  velocity) and magnetic field of the heliosphere with that predicted
  by the model. Near the Sun, we validate the numerical model with the
  electron density obtained from the solar rotational tomography of
  SOHO/LASCO-C2 data in the range of 2.4 to 6 solar radii. Electron
  temperature and density are determined from differential emission
  measure tomography of STEREO A and B EUVI data in the range of 1.035 to
  1.225 solar radii. Moreover, we compare ionic charge states of carbon,
  oxygen, silicon, and iron observed in situ with ACE/SWICS and that
  predicted by our model. The validation results suggest that most of
  the model outputs for CR2077 can fit the observations very well. Based
  on this encouraging result, we therefore expect great improvement for
  the modeling of CMEs and CME-driven shocks in the future.

---------------------------------------------------------
Title: The properties of asteroid (2867) Steins from Spitzer Space
    Telescope observations and OSIRIS shape reconstruction
Authors: Groussin, O.; Lamy, P.; Fornasier, S.; Jorda, L.
2011A&A...529A..73G    Altcode: 2011arXiv1104.5328G
  <BR /> Aims: We report on the thermal properties and composition of
  asteroid (2867) Steins derived from an analysis of new Spitzer Space
  Telescope (SST) observations performed in March 2008, in addition to
  previously published SST observations performed in November 2005. <BR />
  Methods: We consider the three-dimensional shape model and photometric
  properties derived from OSIRIS images obtained during the flyby of the
  Rosetta spacecraft in September 2008, which we combine with a thermal
  model to properly interpret the observed SST thermal light curve and
  spectral energy distributions. <BR /> Results: We obtain a thermal
  inertia of 100 ± 50 J K<SUP>-1</SUP> m<SUP>-2</SUP> s<SUP>-1/2</SUP>
  and a beaming factor (roughness) in the range 0.7-1.0. We confirm
  that the infrared emissivity of Steins is consistent with an enstatite
  composition. The November 2005 SST thermal light curve is most reliably
  interpreted by assuming inhomogeneities in the thermal properties
  of the surface, with two different regions of slightly different
  roughness, as observed on other small bodies, such as the nucleus
  of comet 9P/Tempel 1. Our results emphasize that the shape model is
  important to an accurate determination of the thermal inertia and
  roughness. Finally, we present temperature maps of Steins, as seen
  by Rosetta during its flyby, and discuss the interpretation of the
  observations performed by the VIRTIS and MIRO instruments.

---------------------------------------------------------
Title: Earth-based detection of the millimetric thermal emission
    from the nucleus of comet 8P/Tuttle
Authors: Boissier, J.; Groussin, O.; Jorda, L.; Lamy, P.;
   Bockelée-Morvan, D.; Crovisier, J.; Biver, N.; Colom, P.; Lellouch,
   E.; Moreno, R.
2011A&A...528A..54B    Altcode: 2011arXiv1101.3415B
  Context. Little is known about the physical properties of cometary
  nuclei. Measuring the thermal emission of a nucleus is one of
  the few means of deriving its size, independently of its albedo,
  and constraining some of its thermal properties. This emission is
  difficult to detect from Earth but space telescopes, such as th
  Infrared Space Observatory, Spitzer Space Telescope, and Herschel
  Space Observatory, allow reliable measurements to be made in the
  infrared and the sub-millimetre domains. <BR /> Aims: We attempt to
  characterize more accurately the thermal properties of the nucleus
  of comet 8P/Tuttle using multiwavelength space- and ground-based
  observations, in the visible, infrared, and millimetre range. <BR />
  Methods: We used the Plateau de Bure Interferometer to measure the
  millimetre thermal emission of comet 8P/Tuttle at 240 GHz (1.25 mm)
  and analysed the observations with the shape model derived from Hubble
  Space Telescope observations and the nucleus size derived from Spitzer
  Space Telescope observations. <BR /> Results: We report on the first
  detection of the millimetre thermal emission of a cometary nucleus since
  comet C/1995 O1 Hale-Bopp in 1997. Using the two contact-sphere shape
  model derived from Hubble Space Telescope observations, we constrain the
  thermal properties of the nucleus. Our millimetre observations are most
  accurately reproduced by assuming: i) a thermal inertia lower than ~10
  J K<SUP>-1</SUP> m<SUP>-2</SUP> s<SUP>-1/2</SUP>, and ii) an emissivity
  lower than 0.8, which is indicative of a non-negligible contribution
  of the colder sub-surface layers to the outcoming millimetre flux. <P
  />Based on observations carried out with the IRAM Plateau de Bure
  Interferometer. IRAM is supported by INSU/CNRS (France), MPG (Germany)
  and IGN (Spain).

---------------------------------------------------------
Title: Properties of the nuclei and comae of 10 ecliptic comets from
    Hubble Space Telescope multi-orbit observations
Authors: Lamy, P. L.; Toth, I.; Weaver, H. A.; A'Hearn, M. F.;
   Jorda, L.
2011MNRAS.412.1573L    Altcode: 2011MNRAS.tmp..381L
  We report on our on-going effort to detect and characterize cometary
  nuclei with the Hubble Space Telescope (HST). During cycle 9 (2000 July
  to 2001 June), we performed multi-orbit observations of 10 ecliptic
  comets with the Wide Field Planetary Camera 2. Nominally, eight
  contiguous orbits covering a time interval of ∼11 h were devoted
  to each comet but a few orbits were occasionally lost. In addition
  to the standard R band, we could additionally observe four of them
  in the V band and the two brightest ones in the B band. Time series
  photometry was used to constrain the size, shape and rotational period
  of the 10 nuclei. Assuming a geometric albedo of 0.04 for the R band,
  a linear phase law with a coefficient of 0.04 mag deg<SUP>-1</SUP>
  and an opposition effect similar to that of comet 19P/Borrelly,
  we determined the following mean values of the effective radii
  47P/Ashbrook-Jackson: 2.86±0.08 km, 61P/Shajn-Schaldach: 0.62±0.02
  km, 70P/Kojima: 1.83±0.05 km, 74P/Smirnova-Chernykh: 2.23±0.04 km,
  76P/West-Kohoutek-Ikemura: 0.30±0.02 km, 82P/Gehrels 3: 0.69±0.02
  km, 86P/Wild 3: 0.41±0.03 km, 87P/Bus: 0.270.01 km, 110P/Hartley 3:
  2.15±0.04 km and 147P/Kushida-Muramatsu: 0.21±0.01 km. Because of
  the limited time coverage (∼11 h), the rotational periods could not
  be accurately determined, multiple solutions were sometime found and
  three periods were not constrained at all. Our estimates range from
  ∼5 to ∼32 h. The lower limits for the ratio a/b of the semi-axis of
  the equivalent spheroids range from 1.10 (70P) to 2.20 (87P). The four
  nuclei for which we could measure (V-R) are all significantly redder
  than the Sun, with 86P/Wild 3 (V-R) = 0.86 ± 0.10 appearing as an
  ultrared object. We finally determined the dust activity parameter Afρ
  of their coma in the R band, the colour indices and the reflectivity
  spectra of four of them. Based on observations made with the NASA/ESA
  Hubble Space Telescope, obtained at Space Telescope Science Institute,
  which is operated by the Association of Universities for Research in
  Astronomy under NASA contract NAS 5-26555.

---------------------------------------------------------
Title: Physical Properties of Craters on Asteroid (21) Lutetia
Authors: Vincent, J. -B.; Marchi, S.; Besse, S.; Böhnhardt, H.;
   Sierks, H.; A'Hearn, M.; Angrilli, F.; Barbieri, C.; Barucci, A.;
   Cremonese, G.; da Deppo, V.; Davidsson, B.; Debei, S.; de Cecco, M.;
   Fornasier, S.; Fulle, M.; Groussin, O.; Gutierrez, P.; Hviid, S. F.;
   Ip, W. -H.; Keller, H. U.; Kramm, J. R.; Knollenberg, J.; Koschny,
   D.; Kuehrt, E.; Kueppers, M.; Lamy, P.; Lara, L. M.; Lazzarin, M.;
   Lopez-Moreno, J. J.; Magrin, S.; Marzari, F.; Massironi, M.; Michalik,
   H.; Naletto, G.; Rickman, H.; Rodrigo, R.; Sabau, L.; Thomas, N.;
   Wenzel, K. -P.
2011LPI....42.2417V    Altcode:
  This abstract presents the physical properties of craters derived from
  the measurement of depth/diameter ratios on asteroid (21) Lutetia. We
  show how the d/D ratio varies in different regions and how it can be
  used to better understand the processes that affected the surface.

---------------------------------------------------------
Title: Partition of Proton and Electron Heating in the Solar Wind
    (Invited)
Authors: van der Holst, B.; Jin, M.; Manchester, W. B.; Frazin, R. A.;
   Vasquez, A. M.; Lamy, P. L.; Llebaria, A.; Gombosi, T. I.
2010AGUFMSH41E..01V    Altcode:
  The electron and proton temperature profiles in the solar wind are
  very nonadiabatic so that additional heat deposition is needed for both
  species. A possible heating source is the Kolmogorov-like dissipation of
  the Alfvén waves. It is still an open issue how turbulence partitions
  the heat between the electrons and protons (see, e.g., Stawarz et
  al., 2009 and Breech et al., 2009). Comparison of empirical electron
  temperature, derived from differential emission measure tomography
  (DEMT) applied to STEREO A and B EUVI images, with numerical solar wind
  models allows us to constrain this heating partition. The DEMT results
  cover the height range 1.035 to 1.225 Rsun. The densities are compared
  to the solar rotational tomography on LASCO-C2 data of SOHO to further
  constrain the wind acceleration and heating models. We specifically
  analyze the periods of Carrington rotations 2077 and 2095. We use the
  recently developed three-dimensional two-temperature solar wind model
  within the Space Weather Modeling Framework (SWMF), which includes
  the anisotropic electron thermal heat conduction, and the collisional
  heat transfer between the electrons and protons. The solar wind is
  assumed to be accelerated by the Alfvén waves, and we use Kolmogorov
  dissipation of these waves to heat both the protons and electrons.

---------------------------------------------------------
Title: Testing Coronal and Solar Wind MHD Models with UV Spectroscopic
    and Visible Light Coronagraph Data
Authors: Strachan, L.; Panasyuk, A.; Kohl, J. L.; Woolsey, L.; Lamy,
   P. L.
2010AGUFMSH42A..08S    Altcode:
  We present synoptic maps of coronal outflow velocities obtained at 2.3
  Rs in the solar wind acceleration region of the corona during Solar
  Cycle 23. The outflow velocities are obtained by using data from the
  SOHO coronagraphs: H I Lyman alpha and O VI line profiles (from UVCS)
  and white light polarized brightness data (from LASCO). The information
  contained in the maps provide constraints on the electron densities,
  bulk outflow speeds, and anisotropic kinetic temperatures (velocity
  distributions for protons and minor ions. We show some examples of how
  these data can be used to test MHD models of the solar corona and solar
  wind. The data set can be used to compare empirically derived plasma
  parameters directly with the MHD model parameters or alternatively it
  can be used to compare the observed profiles with synthetic profiles
  obtained by forward modeling of the MHD data.

---------------------------------------------------------
Title: Multispacecraft Validation of a Global Two-Temperature Corona
    and Inner Heliosphere Model (Invited)
Authors: van der Holst, B.; Jin, M.; Manchester, W. B.; Frazin, R. A.;
   Vasquez, A. M.; Lamy, P. L.; Llebaria, A.; Gombosi, T. I.
2010AGUFMSH42A..05V    Altcode:
  During the recent solar minimum, the two STEREO spacecrafts have imaged
  many Corotating Interaction Regions (CIRs) in the interplanetary
  medium. The multi-spacecraft view of the CIRs during this period of
  very low activity is a unique opportunity for validating solar wind
  models. According to the National Oceanic and Atmospheric Administration
  Space Weather Prediction Center the absolute minimum of Sunspots number
  for solar cycle 23 happened during CR2077 (2008, November 20 through
  December 17). We use this rotation to perform a multi-spacecraft
  validation study for a recently developed three-dimensional
  two-temperature and Alfvén wave driven global solar wind model
  within the Space Weather Modeling Framework (SWMF). We compare the
  CIRs of this model with in situ STEREO A and B, ACE/WIND as well as
  Venus Express. Near the Sun, we validate the numerical model with the
  density obtained from the solar rotational tomography on LASCO-C2 data
  of SOHO in the height range of 2.4 to 6 Rsun and electron temperature
  and density from differential emission measure tomography on STEREO
  A and B EUVI images in the height range of 1.035 to 1.225 Rsun.

---------------------------------------------------------
Title: Imaging Asteroid (21) Lutetia with OSIRIS onboard Rosetta
    (Invited)
Authors: Keller, H.; Barbieri, C.; Koschny, D.; Lamy, P. L.; Rickman,
   H.; Rodrigo, R.; Sierks, H.; OSIRIS Team
2010AGUFM.P14B..02K    Altcode:
  The Optical, Spectroscopic, and Infrared Remote Imaging System
  OSIRIS observed the asteroid (21) Lutetia during the fly-by of ESA’s
  Rosetta spacecraft on 10. July 2010. Observations with the narrow angle
  (NAC) and wide angle (WAC) cameras covered a large phase angle range
  (from 10 deg during approach through near zero reaching almost 150
  deg after closest approach (CA)). The large field of view (2048 x
  2048 pixels) of the narrow angle camera (NAC) was almost filled by
  the 100 km sized body at CA from a distance of 3160 km providing
  a scale of 60 m per pixel. The rugged body of (21) Lutetia appears
  to be shaped by an extensive collision history resulting in crater
  diameters comparable to the mean radius of the asteroid. Most of
  the visible northern hemisphere is scarred by numerous craters and
  therefore geologically old. However, several recent large impacts have
  covered their surroundings with thick layers of regolith. In addition
  to a wide variety of crater shapes a large diversity of geological
  features can be discerned: ridges, grabens, pits, landslides, talus,
  and boulders (&gt; 150 m) and boulder tracks. Grooves are pervasive,
  radially aligned or concentric around recent craters, often cutting
  older craters indicating strong seismic activity caused by frequent
  impacts. In contrast to the observations of asteroid (2867) Steins
  weak variations of the surface albedo and colour variegations can be
  discerned and correlated with surface features. The observed opposition
  effect will constrain the properties of the regolith such as its grain
  size. The spectrum of Lutetia over the wavelength range of 250 to 1000
  nm covered by the filters of the WAC and NAC is flat and hence Lutetia
  does not appear as red as Steins. Detailed photometric modeling taking
  advantage of the wide range of phase angles and spectral coverage will
  be combined and iterated with digital terrain models to describe the
  surface topography down to the resolution limit of the images and the
  overall shape to Lutetia.

---------------------------------------------------------
Title: Multi-color, rotationally resolved photometry of asteroid 21
    Lutetia from OSIRIS/Rosetta observations
Authors: Lamy, P. L.; Faury, G.; Jorda, L.; Kaasalainen, M.; Hviid,
   S. F.
2010A&A...521A..19L    Altcode:
  Context. Asteroid 21 Lutetia is the second target of the Rosetta space
  mission. Extensive pre-encounter, space-, and ground-based observations
  are being performed to prepare for the flyby in July 2010. <BR />
  Aims: The aim of this article is to accurately characterize the
  photometric properties of this asteroid over a broad spectral range
  from the ultraviolet to the near-infrared and to search for evidence of
  surface inhomogeneities. <BR /> Methods: The asteroid was imaged on 2
  and 3 January 2007 with the Narrow Angle Camera (NAC) of the Optical,
  Spectroscopic, and Infrared Remote Imaging System (OSIRIS) during
  the cruise phase of the Rosetta spacecraft. The geometric conditions
  were such that the aspect angle was 44^circ (i.e., mid-northern
  latitudes) and the phase angle 22.4^circ. Lutetia was continuously
  monitored over 14.3 h, thus exceeding one rotational period and a
  half, with twelve filters whose spectral coverage extended from 271
  to 986 nm. An accurate photometric calibration was obtained from
  the observations of a solar analog star, 16 Cyg B. <BR /> Results:
  High-quality light curves in the U, B, V, R and I photometric bands
  were obtained. Once they were merged with previous light curves from
  over some 45 years, the sidereal period is accurately determined:
  P<SUB>rot</SUB> = 8.168271 ± 0.000002 h. Color variations with
  rotational phase are marginally detected with the ultraviolet
  filter centered at 368 nm but are absent in the other visible and
  near-infrared filters. The albedo is directly determined from the
  observed maximum cross-section obtained from an elaborated shape model
  that results from a combination of adaptive-optics imaging and light
  curve inversion. Using current solutions for the phase function, we find
  geometric albedos p<SUB>V</SUB> = 0.130 ± 0.014 when using the linear
  phase function and p<SUB>V</SUB>(H-G) = 0.180 ± 0.018 when using the
  (H-G) phase function, which incorporates the opposition effect. The
  spectral variation of the reflectance indicates a steady decrease with
  decreasing wavelength rather than a sharp fall-off. <P />Photometric
  tables (Tables 4 to 8) are only available in electronic form at the
  CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/521/A19">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/521/A19</A>

---------------------------------------------------------
Title: Visible-wavelength Observations of Jupiter-family Comet Nuclei
    as Part of Seppcon.
Authors: Pittichova, Jana; Lowry, S. C.; Laird, R.; A'Hearn, M. F.;
   Bauer, J. M.; Campins, H.; Fernández, Y.; Fitzsimmons, A.; Groussin,
   O.; Hsieh, H.; Kelley, M.; Lamy, P.; Licandro, J.; Lisse, C. M.;
   Meech, K. J.; Reach, W. T.; Snodgrass, C.; Toth, I.; Weaver, H. A.;
   Weaissman, P.
2010DPS....42.2826P    Altcode: 2010BAAS...42..964P
  We present the latest analysis and results from SEPPCoN (Survey of
  Ensemble Physical Properties of Cometary Nuclei). This on-going survey
  involves studying 100 JFCs - about 25% of the known population - at both
  mid-infrared and visible wave-lengths to constrain the distributions of
  sizes, shapes, spins, and albedos of this population. Having earlier
  reported results from measuring thermal emissions of our sample
  nuclei [1,2,3,4], we report here progress on the visible-wavelength
  observations that we have obtained at many ground-based facilities
  in Chile, Spain, and the United States. To date we have attempted
  observations of 91% of our sample of 100 JFCs, and at least 64 of
  those were successfully detected. In most cases the comets were at
  heliocentric distances between 3.0 and 6.5 AU so as to decrease the
  odds of a comet having a coma. Of the 64 detected comets, 48 were
  apparently bare, having no extended emission. Our datasets are further
  augmented by archival data and photometry from the NEAT program [5]. An
  important goal of SEPPCoN is to accumulate a large comprehensive set
  of high quality physical data on cometary nuclei in order to make
  accurate statistical comparisons with other minor-body populations
  such as Trojans, Centaurs, and Kuiper-belt objects. Information
  on the size, shape, spin-rate, albedo and color distributions is
  critical for understanding their origins and evolutionary processes
  affecting them. <P />This work was supported in part by grants from NASA
  (NNX09AB44G) and NSF (AST-0808004). <P />[1] Fernandez, Y., et al. 2008,
  Asteroids Comets Mete-ors 2008, LPI Co. No. 1405, paper id. 8307. <P
  />[2] Kelley, M., et al. 2008, Asteroids Comets Meteors 2008, LPI
  Co. No. 1405, paper id. 8272. <P />[3] Groussin, O., et al. 2009,
  Icarus 199, 568. <P />[4] Licandro, J., et al. 2009, A&amp;A 507,
  1667. <P />[5] Bauer, J., et al. 2010, AAS Meeting 216, paper 409.01.

---------------------------------------------------------
Title: A collision in 2009 as the origin of the debris trail of
    asteroid P/2010A2
Authors: Snodgrass, Colin; Tubiana, Cecilia; Vincent, Jean-Baptiste;
   Sierks, Holger; Hviid, Stubbe; Moissi, Richard; Boehnhardt, Hermann;
   Barbieri, Cesare; Koschny, Detlef; Lamy, Philippe; Rickman, Hans;
   Rodrigo, Rafael; Carry, Benoit; Lowry, Stephen C.; Laird, Ryan J. M.;
   Weissman, Paul R.; Fitzsimmons, Alan; Marchi, Simone; OSIRIS Team
2010Natur.467..814S    Altcode: 2010arXiv1010.2883S
  The peculiar object P/2010A2 was discovered in January 2010 and given
  a cometary designation because of the presence of a trail of material,
  although there was no central condensation or coma. The appearance of
  this object, in an asteroidal orbit (small eccentricity and inclination)
  in the inner main asteroid belt attracted attention as a potential
  new member of the recently recognized class of main-belt comets. If
  confirmed, this new object would expand the range in heliocentric
  distance over which main-belt comets are found. Here we report
  observations of P/2010A2 by the Rosetta spacecraft. We conclude that
  the trail arose from a single event, rather than a period of cometary
  activity, in agreement with independent results. The trail is made up
  of relatively large particles of millimetre to centimetre size that
  remain close to the parent asteroid. The shape of the trail can be
  explained by an initial impact ejecting large clumps of debris that
  disintegrated and dispersed almost immediately. We determine that this
  was an asteroid collision that occurred around 10 February 2009.

---------------------------------------------------------
Title: VizieR Online Data Catalog: 21 Lutetia UBVRI light curves
    (Lamy+, 2010)
Authors: Lamy, P.; Faury, G.; Jorda, L.; Kaasalainen, M.; Hviid, S. F.
2010yCat..35210019L    Altcode: 2010yCat..35219019L
  The asteroid was imaged on 2 and 3 January 2007 with the Narrow Angle
  Camera (NAC) of the Optical, Spectroscopic, and Infrared Remote Imaging
  System (OSIRIS) during the cruise phase of the Rosetta spacecraft. The
  geometric conditions were such that the aspect angle was 44° (i.e.,
  mid-northern latitudes) and the phase angle 22.4°. Lutetia was
  continuously monitored over 14.3h, thus exceeding one rotational period
  and a half, with twelve filters whose spectral coverage extended from
  271 to 986nm. An accurate photometric calibration was obtained from
  the observations of a solar analog star, 16 Cyg B. <P />(5 data files).

---------------------------------------------------------
Title: The P/2010 A2 Asteroid Collision Confirmed by Rosetta/OSIRIS
    Observation
Authors: Snodgrass, Colin; Tubiana, C.; Vincent, J.; Sierks, H.;
   Hviid, S.; Moissl, R.; Boehnhardt, H.; Barbieri, C.; Koschny, D.;
   Lamy, P.; Rickman, H.; Rodrigo, R.; Carry, B.; Lowry, S. C.; Laird,
   R. J. M.; Weissman, P. R.; Fitzsimmons, A.; Marchi, S.; OSIRIS Team
2010DPS....42.3933S    Altcode:
  The discovery of P/2010 A2 by the LINEAR survey in January 2010 revealed
  an object displaying a large trail of material similar in shape to
  a cometary tail although no central condensation or coma could be
  detected. The appearance of this object in an asteroidal orbit in the
  inner main belt attracted attention as a potential new member of the
  Main Belt Comets class (MBCs) but the discovery of a nucleus, with
  an estimated diameter of 120 m, around 1500 km away from the trail
  implied that the extended object we were seeing could be the debris
  trail from a recent collision rather than the tail of a comet. Due to
  the low inclination of its orbit, it is difficult to conclude about the
  nature of P/2010 A2 from Earth-based data only, as different scenarios
  lead to the same appearance in the orbital configuration at the times
  of observations. We present here another set of images, acquired from
  the unique viewing geometry provided by ESA's Rosetta spacecraft en
  route to comet 67P/Churyumov-Gerasimenko. Albeit faint (22 magnitude),
  the object could be observed by the high-resolution camera OSIRIS. We
  used a Finson-Probstein model to simulate the shape of the trail, and
  estimate the time of emission and β parameter (ratio between solar
  radiation pressure and gravity) for the dust grains. Simulations were
  compared to the OSIRIS images and ground based observations acquired
  at NTT and Palomar telescopes. Thanks to the different phase angle
  provided by Rosetta, we could reduce the number of solutions to a
  unique model, leading to the conclusive demonstration that the trail
  is due to a single event rather than a period of cometary activity.

---------------------------------------------------------
Title: Properties And Distribution Of The Craters Of Asteroid (21)
    Lutetia From The Rosetta\Osiris Fly-by
Authors: Besse, Sebastien; Lamy, P.; Jorda, L.; Groussin, O.; Marchi,
   S.; Debei, S.; Da Deppo, V.; Ferri, F.; Keller, H. U.; Kueppers,
   M.; Massironi, M.; Moissl, R.; Sierks, H.; Thomas, N.; Tubiana, C.;
   Vincent, J.; OSIRIS Team
2010DPS....42.3903B    Altcode: 2010BAAS...42R1032B
  The Rosetta spacecraft of the European Space Agency performed
  successfully its second flyby of an asteroid on July 10 2010 on its
  way to its final target comet 67p/Churyumov-Gerasimenko. Main belt
  asteroid (21) Lutetia has been observed by the OSIRIS experiment at
  a distance of 3160 km. The best resolution of the images is about 59
  meters per pixel, numerous geological features can be distinguished
  at this scale. We report on here the physical characteristics and
  properties of the craters of the largest (100km in diameter) asteroid
  ever observed in-situ. The values of the diameter and the depth of
  the craters are essential to determine the age of the surface based
  on crater counting and the evolution of the surface. Preliminary
  observations already attest for a highly impacted surface with very
  large craters. Displacement of regolith is seen on the surface and
  especially in the walls of craters. The properties of the craters
  will help understand the history and evolution of this large scale
  and possible primordial body.

---------------------------------------------------------
Title: Hints on the Puzzling 21 Lutetia Nature from OSIRIS Rosetta
    Data
Authors: Barucci, Maria Antonieta; Sierks, H.; Barbieri, C.; Koschny,
   D.; Lamy, P.; Rickman, H.; Rodrigo, R.; Keller, U. H.; OSIRIS Team
2010DPS....42.4301B    Altcode: 2010BAAS...42.1043B
  From the ground based observations, 21 Lutetia appeared to be a
  puzzling asteroid different from all the other asteroids. Its nature was
  uncertain because of contradictory observations, either favoring an M
  type or a C type asteroid. From polarimetry (Belskaya et al. 2010, AA,
  515, 29), Lutetia appeared an atypical object with a surface covered
  by a fine-grained regolith. <P />From the amazing images received by
  OSIRIS imaging system (Keller et al. 2007 SSRev. 128, 433), on board of
  ESA Rosetta spacecraft, Lutetia reveals a complex and morphologically
  diverse surface. <P />Lutetia seems to be a very old object with an
  irregular shape which is the result of its collisional history. Some
  smooth younger areas have been also observed. The asteroid lifelong
  bombardment produced several big craters (tens of kilometers), and
  many different generations of smaller craters. An apparently thick
  regolith layer probably covers most of the surface of the asteroid and
  its presence is revealed by the unique land slide structures along the
  walls of some craters, most likely generated by impact-induced seismic
  activity. The presence inside some big craters of sparse boulders,
  apparently dark, indicates a complex impact mechanism. Moreover images
  display a great richness of different structures: pits, craters chains,
  ridges, scarps and wide younger terrains. More details will be available
  at the time of the presentation. An overview of the obtained results
  will be presented. <P />The first analysis of the data shows the
  extreme diversity of Lutetia which does not resemble any other space
  explored asteroid. The variety of shapes, morphologies, structures,
  histories provides us with an invaluable patrimony of information.

---------------------------------------------------------
Title: Shape and Physical Properties of Asteroid 21 Lutetia from
    OSIRIS Images
Authors: Jorda, Laurent; Lamy, P.; Besse, S.; Capanna, C.; Carry,
   B.; Faury, G.; Gaskell, R.; Gesquière, G.; Groussin, O.; Gutiérrez,
   P.; Kaasalainen, M.; Sabolo, W.; Sierks, H.; Spjuth, S.; OSIRIS Team
2010DPS....42.4303J    Altcode: 2010BAAS...42.1043J
  The Rosetta spacecraft of the European Space Agency flew by the asteroid
  21 Lutetia on July, 10, 2010 on its way to its final target, comet
  67P/Churyumov-Gerasimenko. A total of 460 images have been acquired by
  OSIRIS during the flyby, with a minimum pixel scale of 64 m at closest
  approach (hereafter "CA") with the narrow angle camera. Several filters
  have been used, covering a wavelength range from the far UV (0.25
  microns) to the end of the visible spectrum (1.0 microns). The phase
  angle went through 11°-0°-160°, reaching opposition 18 min before
  CA. We report here on a preliminary interpretation of the images of the
  asteroid acquired by OSIRIS, the imaging system aboard Rosetta. These
  images are combined with pre-flyby light curves and adaptive optics
  measurements to retrieve the shape and the rotational parameters of
  the asteroid. The bulk physical properties: size, surface, volume,
  moments of inertia, gravity field, are then extracted from the shape.

---------------------------------------------------------
Title: Thermal properties of asteroids 21 Lutetia and 2867 Steins
    from Spitzer Space Telescope observations
Authors: Groussin, O.; Lamy, P. L.; Fornasier, S.; Jorda, L.;
   Kaasalainen, M.; Carry, B.
2010epsc.conf...55G    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Hektor : a space mission towards Jupiter Trojans
Authors: Lamy, P.; Poncy, J.; Martinot, V.; Jorda, L.; Delsanti, A.;
   Groussin, O.
2010epsc.conf..138L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Asteroid collision confirmed by Rosetta/OSIRIS observations
Authors: Vincent, J. -B.; Snodgrass, C.; Tubiana, C.; Sierks, H.;
   Hviid, S.; Moissl, R.; Böhnhardt, H.; Barbieri, C.; Koschny, D.;
   Lamy, P.
2010epsc.conf..634V    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: 21 Lutetia: Overview of results from OSIRIS images
Authors: Sierks, H.; Barbieri, C.; Koschny, D.; Lamy, P.; Rickman,
   H.; Rodrigo, R.; OSIRIS Team
2010epsc.conf..664S    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The shape and physical properties of asteroid 2867 Steins
    from OSIRIS images
Authors: Lamy, P.; Jorda, L.; Spjuth, S.; Besse, S.; Marchi, S.;
   Barbieri, C.; Gaskell, R.; Groussin, O.; Kaasalainen, M.; Keller, H. U.
2010epsc.conf..204L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: THERMAP: a thermal infrared spectro-imager for space missions
    to small bodies of the solar system
Authors: Brageot, E.; Groussin, O.; Lamy, P.; Reynaud, J. -L.;
   Fargant, G.
2010epsc.conf...51B    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Restitution of multiple overlaid components on extremely long
    series of solar corona images
Authors: Llebaria, A.; Loirat, J.; Lamy, P.
2010ada..confE..12L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The shape and physical properties of asteroid 21 Lutetia from
    OSIRIS images
Authors: Jorda, L.; Lamy, P.; Besse, S.; Capanna, C.; Carry, B.;
   Faury, G.; Gaskell, R.; Gesquiere, G.; Groussin, O.; Kaasalainen, M.
2010epsc.conf..200J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Three-Dimensional Electron Density from Tomographic Analysis
    of LASCO-C2 Images of the K-Corona Total Brightness
Authors: Frazin, Richard A.; Lamy, Philippe; Llebaria, Antoine;
   Vásquez, Alberto M.
2010SoPh..265...19F    Altcode: 2010SoPh..tmp...79F
  We present the first quantitative three-dimensional (3D) tomographic
  reconstructions of electron density from coronagraph measurements of
  the K-corona's total brightness (B) made by LASCO-C2 on SOHO. This
  is possible because new calibrations of the LASCO-C2 images in both
  polarized brightness (pB) and B have now been made for the entire
  mission. The B and pB reconstructions are compared, and the differences
  are explained in terms of line of sight weighting functions in Thomson
  scattering. We conclude that the LASCO-C2 B archive, which is vastly
  larger than the pB archive, will be a very valuable resource for
  determining the 3D electron density throughout the SOHO mission which
  started taking data in 1996.

---------------------------------------------------------
Title: Analytic and experimental determination of ghosts in the
    Rosetta Narrow-Angle Camera and their impact on imaging performance
Authors: Dohlen, Kjetil; Jorda, Laurent; Lamy, Philippe; Toth, Imre;
   Origne, Alain
2010SPIE.7731E..49D    Altcode: 2010SPIE.7731E.138D
  The Rosetta cometary rendezvous mission, one of ESA's cornerstone
  missions, was launched in 2004 and will be inserted in orbit around
  comet 67P/Churyumov-Gerasimenko in 2014. One of its instruments, the
  Osiris Narrow Angle Camera (NAC), will take high-resolution images
  of the comet and map its nucleus as well as the jets of gas and dust
  emanating from localized areas. This is quite challenging as the
  contrast between the radiance of these jets and that of the nucleus is
  expected to be of the order of 1/1000. A major limitation comes from
  the presence of multiple ghosts which results from the presence of two
  filters and a protective window in front of the CCD detector. Rigorous
  knowledge of these instrumental ghost images is therefore required. We
  present analytical models of the structure and intensity of these
  ghosts, compare them with pre and post-launch observations, and describe
  image analysis tools developed to handle them.

---------------------------------------------------------
Title: The cratering history of asteroid (2867) Steins
Authors: Marchi, S.; Barbieri, C.; Küppers, M.; Marzari, F.;
   Davidsson, B.; Keller, H. U.; Besse, S.; Lamy, P.; Mottola, S.;
   Massironi, M.; Cremonese, G.
2010P&SS...58.1116M    Altcode: 2010arXiv1003.5655M
  The cratering history of main belt asteroid (2867) Steins has been
  investigated using OSIRIS imagery acquired during the Rosetta flyby
  that took place on the 5th of September 2008. For this purpose, we
  applied current models describing the formation and evolution of main
  belt asteroids, that provide the rate and velocity distributions of
  impactors. These models coupled with appropriate crater scaling laws,
  allow the cratering history to be estimated. Hence, we derive Steins'
  cratering retention age, namely the time lapsed since its formation
  or global surface reset. We also investigate the influence of various
  factors - like bulk structure and crater erasing - on the estimated age,
  which spans from a few hundred Myrs to more than 1 Gyr, depending on
  the adopted scaling law and asteroid physical parameters. Moreover,
  a marked lack of craters smaller than about 0.6 km has been found and
  interpreted as a result of a peculiar evolution of Steins cratering
  record, possibly related either to the formation of the 2.1 km wide
  impact crater near the south pole or to YORP reshaping.

---------------------------------------------------------
Title: Stray light analysis and optimization of the ASPIICS/PROBA-3
    formation flying solar coronagraph
Authors: Mazzoli, A.; Landini, F.; Vives, S.; Lamy, P.; Halain, J. P.;
   Rochus, P.
2010SPIE.7731E..46M    Altcode: 2010SPIE.7731E.135M
  PROBA-3 is a technology mission devoted to the in-orbit demonstration
  of formation flying techniques and technologies. PROBA-3 will implement
  a giant coronagraph (called ASPIICS) that will both demonstrate and
  exploit the capabilities and performances of formation flying. ASPIICS
  is distributed on two spacecrafts separated by 150m, one hosting
  the external occulting disk and the other the optical part of the
  coronagraph. This part implements a three-mirror-anastigmat (TMA)
  telescope. Its pupil is placed about 800mm in front of the primary
  mirror, a solution allowing an efficient baffling and a high reduction
  of the stray light inside the instrument. A complete stray light
  analysis of the TMA has been carried out to design the baffles and to
  establish the required roughness of the mirrors. The analysis has been
  performed in two steps: first, by calculating the diffraction pattern
  behind the occulter due to an extended monochromatic source having the
  diameter of the Sun; second, by propagating this diffraction pattern,
  through all the telescope optical components, to the prime focal
  plane. The results obtained are described in this article.

---------------------------------------------------------
Title: Demonstrator of the formation flying solar coronagraph
    ASPIICS/PROBA-3
Authors: Vives, Sébastien; Damé, Luc; Lamy, Philippe; Antonopoulos,
   A.; Bon, W.; Capobianco, G.; Crescenzio, G.; da Deppo, V.; Ellouzi,
   M.; Garcia, J.; Guillon, C.; Mazzoli, A.; Soilly, T.; Stathopoulos,
   F.; Tsiganos, C.
2010SPIE.7731E..47V    Altcode: 2010SPIE.7731E.136V
  Formation Flying opens the possibility to conceive and deploy giant
  solar coronagraphs in space permanently reproducing the optimum
  conditions of a total eclipse of the Sun ("artificial" eclipse) thus
  giving access to the inner corona with unprecedented spatial resolution
  and contrast (low stray light). The first opportunity to implement such
  a coronagraph "ASPIICS" will be offered by the European Space Agency
  (ESA) PROBA-3 technology mission devoted to the in-orbit demonstration
  of formation flying technologies. Two spacecrafts separated by about 150
  m form a giant externally-occulted coronagraph: the optical part hosted
  by one spacecraft remains entirely protected from direct sunlight
  by remaining in the shadow of an external occulter hosted by the
  other spacecraft. We developed and tested a scale-model 'breadboard'
  (i.e., 30m) of the PROBA-3/ASPIICS Formation Flying coronagraph. The
  investigations focused on two metrology systems capable of measuring
  both the absolute pointing of the coronagraph (by sensing the projected
  shadow and penumbra produced by the external occulting disk) and
  the alignment of the formation (by re-imaging light sources located
  on the rear-side of the occulting disk with the optical part of the
  coronagraph). In this contribution, we will describe the demonstrator
  and report on our results on the crucial question of the alignment and
  pointing in space of long instruments (&gt; 100 m) with an accuracy of
  a few arcsec. This study has been conducted in the framework of an ESA
  "STARTIGER" Initiative, a novel approach aimed at demonstrating the
  feasibility of a new and promising technology on a very short time scale
  (six months).

---------------------------------------------------------
Title: ASPIICS: a giant coronagraph for the ESA/PROBA-3 Formation
    Flying Mission
Authors: Lamy, Philippe; Damé, Luc; Vivès, Sébastien; Zhukov, Andrei
2010SPIE.7731E..18L    Altcode: 2010SPIE.7731E..31L
  Classical externally-occulted coronagraphs are presently limited in
  their performances by the distance between the external occulter and
  the front objective. The diffraction fringe from the occulter and the
  vignetted pupil which degrades the spatial resolution prevent useful
  observations of the white light corona inside typically 2-2.5 solar
  radii. Formation flying offers an elegant solution to these limitations
  and allows conceiving giant, externally-occulted coronagraphs using a
  two-component space system with the external occulter on one spacecraft
  and the optical instrument on the other spacecraft at a distance of
  hundred meters. Such an instrument, ASPIICS (Association de Satellites
  Pour l'Imagerie et l'Interférométrie de la Couronne Solaire), has
  just been selected by the European Space Agency (ESA) to fly (launch
  expected in 2014) on its third PROBA (Project for On-Board Autonomy)
  mission of formation flying demonstration which is presently in phase
  B. It will perform both high spatial resolution imaging of the solar
  corona as well as 2- dimensional spectroscopy of several emission
  lines (in particular the forbidden line of FeXIV at 530.285 nm) from
  the coronal base out to 3 solar radii. For this, it will use filters,
  polarisers and a solid Fabry-Perot interferometer ("étalon"). The
  classical design of an externally-occulted coronagraph is adapted to the
  formation flying configuration allowing the detection of the very inner
  corona as close as 0.04-0.05 solar radii (40-50 arcsec) from the solar
  limb. By tuning the position of the occulter spacecraft, it may even be
  possible to reach the chromosphere and the upper part of the spicules.

---------------------------------------------------------
Title: Measurements and optimization of the occulting disk for the
    ASPIICS/PROBA-3 formation flying solar coronagraph
Authors: Landini, Federico; Mazzoli, Alexandra; Venet, Melanie;
   Vivès, Sébastien; Romoli, Marco; Lamy, Philippe; Rossi, Guglielmo
2010SPIE.7735E..4DL    Altcode: 2010SPIE.7735E.146L
  Solar coronagraphs in formation ying require several mechanical and
  technological constraints to be met. One of the most critical issues is
  the external occulter design and its optimization. The occulter edge
  requires special attention in order to minimize the diraction while
  being compatible with the constraints of handling and integrating large
  delicate space components. Moreover, it is practically impossible to
  realize a full scale model for laboratory tests. This article describes
  the results of tests performed with a scaled-model breadboard of the
  ASPIICS coronagraph disk edge, using the Articial Sun facility at
  Laboratoire d'Astrophysique de Marseille.

---------------------------------------------------------
Title: Towards a New Formation Flying Solar Coronagraph
Authors: Lamy, P.; Vives, S.; Curdt, W.; Dame, L.; Davila, J.; Defise,
   J. M.; Fineschi, S.; Heinzel, P.; Kuzin, S.; Schmutz, W.; Tsinganos,
   K.; Turck-Chieze, S.; Zhukov, A.
2010ASPC..424...15L    Altcode:
  We briefly describe an investigation aiming at the development of a
  giant solar coronagraph instrument onboard of two satellites, separated
  by about 150 m in formation flight for the detailed observation of the
  solar coronal plasma. The European Space Agency (ESA) has selected this
  instrument as the only payload onboard the Proba 3 satellites which
  will be launched in 2013. The Greek team is developing the command
  control board of the coronagraph.

---------------------------------------------------------
Title: The Solar Wind as Seen by SOHO/SWAN Since 1996: Comparison
    with SOHO/LASCO C2 Coronal Densities
Authors: Lallement, R.; Quémerais, E.; Lamy, P.; Bertaux, J. -L.;
   Ferron, S.; Schmidt, W.
2010ASPC..428..253L    Altcode: 2010arXiv1003.4243L
  We update the SOHO/SWAN H Lyman-α brightness analysis to cover the
  1996-2008 time interval. A forward model applied to the intensity
  maps provides the latitude and time dependence of the interstellar
  hydrogen ionization rate over more than a full solar cycle. The hydrogen
  ionization, being almost entirely due to charge-exchange with solar
  wind ions, reflects closely the solar wind flux. Our results show
  that the solar wind latitudinal structure during the present solar
  minimum is strikingly different from the previous minimum, with a
  much wider slow solar wind equatorial belt which persists until at
  least the end of 2008. We compute absolute values of the in-ecliptic H
  ionization rates using OMNI solar wind data and use them to calibrate
  our ionization rates at all heliographic latitudes. We then compare
  the resulting fluxes with the synoptic LASCO/C2 electron densities at
  6 solar radii. The two time-latitude patterns are strikingly similar
  over all the cycle. This comparison shows that 6 R<SUB>s</SUB> densities
  can be used to infer the solar wind type close to its source, with high
  (low) densities tracing the slow (fast) solar wind, simply because the
  density reflects the altitude at which the acceleration occurs. The
  comparison between the two minima suggests that the fast polar wind
  acceleration occurs at a larger distance during the current minimum
  compared to the previous one. This difference, potentially linked to
  the magnetic field decrease and/or the coronal temperature decrease
  should be reproduced by solar wind expansion models.

---------------------------------------------------------
Title: Thermal properties of asteroid 21 Lutetia from Spitzer Space
    Telescope observations
Authors: Lamy, P. L.; Groussin, O.; Fornasier, S.; Jorda, L.;
   Kaasalainen, M.; Barucci, M. A.
2010A&A...516A..74L    Altcode:
  Context. Asteroid 21 Lutetia is the second target of the Rosetta
  space mission with a flyby scheduled in July 2010. To best prepare the
  observational campaign, Lutetia is being extensively characterized by
  ground- and space-based astronomical facilities. <BR /> Aims: We used
  the Spitzer Space Telescope (SST) to determine the thermal properties
  of Lutetia and more generally, to contrain its physical properties
  and nature. <BR /> Methods: The observations were performed with the
  infrared spectrograph (IRS) of the SST on 10 and 11 December 2005,
  when the asteroid was 2.81 AU from the Sun, 2.65 AU from the SST and
  at a phase angle of 21°. We obtained 14 spectra ranging from 5.2 to
  38.0 μm, and sampling the rotational period of the asteroid. They were
  interpreted with a standard thermal model incorporating the thermal
  inertia. <BR /> Results: We obtained the first thermal light curve
  of Lutetia. Using the most recent solution for its three-dimensional
  shape and rotational state, as well as independently determined
  parameters such as the albedo, we satisfactorily reproduced the 14
  spectral energy distributions and the complete thermal light curve
  of Lutetia. The best thermal model has a thermal inertia I ≤ 30
  JK<SUP>-1</SUP>m<SUP>-2</SUP>s<SUP>-1/2</SUP> and a beaming factor in
  the range ~0.70-0.83. This low thermal inertia is typical of main belt
  asteroids and implies that the surface of Lutetia is likely covered
  by a thick regolith layer. Since the beaming factor only reflects the
  effects of surface rugosity, the above range implies a high degree of
  roughness. In addition, our results show evidence of inhomogeneities
  in the surface roughness in the equatorial band of Lutetia.

---------------------------------------------------------
Title: A Hundred Comets: The Visual-Wavelength Observations of the
    Survey of Ensemble Physical Properties of Cometary Nuclei (SEPPCoN)
Authors: Bauer, James M.; Fernandez, Y. R.; Lowry, S. C.; Meech, K. J.;
   Fitzsimmons, A.; Snodgrass, C.; Pittichova, J.; Weaver, H. A.; Lisse,
   C. M.; A'Hearn, M. F.; Campins, H.; Groussin, O.; Kelley, M. S.;
   Lamy, P. L.; Licandro, J.; Reach, W. T.; Toth, I.
2010AAS...21640901B    Altcode: 2010BAAS...41..816B
  We present new results from SEPPCoN, a Survey of Ensemble Physical
  Properties of Cometary Nuclei. This project is currently surveying
  100 Jupiter-family comets (JFCs) to measure the mid-infrared thermal
  emission and visible reflected sunlight of the nuclei. The scientific
  goal is to determine the distributions of radius, geometric albedo,
  thermal inertia, axial ratio, and color among the JFC nuclei. In the
  past we have presented results from the completed mid-IR observations
  of our sample [1]; here we present preliminary results from ongoing,
  broadband visible-wavelength observations of nuclei obtained from a
  variety of ground-based facilities (Mauna Kea, Cerro Pachon, La Silla,
  La Palma, Apache Point, Table Mtn., and Palomar Mtn.), including
  contributions from the Near Earth Asteroid Telescope project (NEAT)
  archive. The nuclei were observed at high heliocentric distance (usually
  over 4 AU) and so many comets show either no or little contamination
  from dust coma. While several nuclei have been observed as snapshots,
  we have multiepoch photometry for many of our targets. With our datasets
  we are building a large database of photometry, and such a database
  is essential to the derivation of albedo and shape of a large number
  of nuclei, and to the understanding of biases in the survey. Support
  for this work was provided by NSF and the NASA Planetary Astronomy
  program. Reference: [1] Fernandez, Y.R., et al. 2007, BAAS 39, 827.

---------------------------------------------------------
Title: The nucleus of comet C/1983 H1 IRAS-Araki-Alcock
Authors: Groussin, O.; Lamy, P. L.; Jorda, L.
2010P&SS...58..904G    Altcode:
  We present a synthetic analysis of all available infrared (2-20 μm)
  and radio (1.3-6.1 cm) observations of comet C/1983 H1 IRAS-Araki-Alcock
  performed during its close approach to Earth in May 1983. We implement a
  model based on a spherical nucleus with a macroscopic mosaic of small
  and numerous active and inactive regions, and take into account the
  strong phase effect in the calculations of the thermal flux (often
  neglected in past interpretations). The orientation of the spin axis
  is assumed to be that determined by Sekanina [1988. Astron. J. 95,
  1876-1894]. Additional constraints coming from visible photometry,
  measurements of the water production rate and the temporal variations
  of the cometary activity are introduced. We derive an equivalent
  nucleus radius of 3.4±0.5 km, consistent with a geometric albedo of
  0.04 ±0.01 and a phase coefficient β=0.04mag deg in the visible,
  and an active fraction of 2.9 ±1.9%. Although the nucleus is probably
  elongated as found in the past ( Sekanina, 1988), we show that the
  relevant measurements were likely contaminated by the contribution of
  a variable coma.

---------------------------------------------------------
Title: The solar wind flux and acceleration height as seen by
    SOHO/SWAN and LASCO/C2
Authors: Lallement, Rosine; Quemerais, Eric; Bertaux, Jean-Loup;
   Lamy, Philippe; Schmidt, Walter
2010EGUGA..12.8445L    Altcode:
  We present an update of the SOHO/SWAN H Lyman-alpha data to cover
  the 1996-2009 time interval. A forward model applied to the intensity
  maps provides the latitude and time dependence of the interstellar H
  ionisation rate over more than a full solar cycle. This ionisation,
  being almost entirely due to charge-exchange with solar wind ions,
  reflects closely the solar wind flux. We show that the solar
  wind latitudinal structure during the present solar minimum is
  strikingly different from the previous minimum, with a much wider
  slow solar wind equatorial belt which persists until at least the
  end of 2008. After calibration of our 3D ionisation rates on OMNI
  in-ecliptic data, we compare the resulting solar wind fluxes with the
  synoptic LASCO/C2 electron densities at 6 Rs. The two time-latitude
  patterns are strikingly similar over all the cycle, high (resp. low)
  H ionisation and 6Rs coronal densities tracing the slow (resp. fast)
  solar wind. This is because the H ionisation reflects the solar wind
  flux and speed, while the coronal density reflects at which altitude
  occurs the acceleration. The comparison between the two minima
  of activity suggests that the high latitude fast wind accelerates
  at larger distance from the Sun surface during the current minimum
  compared to the previous one. This difference, potentially linked to
  the magnetic field decrease or(and) the coronal temperature decrease
  should be reproduced by solar wind expansion models.

---------------------------------------------------------
Title: The Interstellar H Flow: Updated Analysis of SOHO/SWAN Data
Authors: Lallement, Rosine; Quémerais, Eric; Koutroumpa, Dimitra;
   Bertaux, Jean-Loup; Ferron, Stéphane; Schmidt, Walter; Lamy, Philippe
2010AIPC.1216..555L    Altcode: 2014arXiv1405.3474L
  We update two kinds of results obtained with the SWAN instrument on
  board SOHO. First, we use H cell data recorded in 2001 and derive
  the H flow direction in the same way the study was done at solar
  minimum. We again compare with the Helium flow direction and doing
  so correct for the coordinate system change between the Ulysses and
  SOHO missions. The deflection plane we obtain is compatible with our
  previous result within error bars, confirming the potential predominant
  role of the interstellar magnetic field. In a second part, we extend
  the computation of the interstellar H ionization as a function of
  heliographic latitude and time, a quantity which reflects closely
  the SW flux latitudinal structure. The pattern for the present solar
  minimum is strikingly different from the previous minimum, with a much
  wider slow solar wind equatorial belt which persists until at least
  2008. Comparing with synoptic LASCO/C2 electron densities we infer
  from a preliminary study that the acceleration of the high speed solar
  wind occurs at a higher altitude during this minimum compared to the
  previous one, a difference expansion models must be able to reproduce.

---------------------------------------------------------
Title: Photometric Study of the Kreutz Comets Observed by SOHO from
    1996 to 2005
Authors: Knight, Matthew M.; A'Hearn, Michael F.; Biesecker, Douglas
   A.; Faury, Guillaume; Hamilton, Douglas P.; Lamy, Philippe; Llebaria,
   Antoine
2010AJ....139..926K    Altcode:
  We present analysis of the photometry of more than 900 Kreutz comets
  observed by SOHO from 1996 to 2005. The Kreutz comets have "sungrazing"
  orbits with q≈ 1-2 R <SUB>sun</SUB>, high inclinations (i ≈ 143°),
  and periods of 500-1000 years. We find that they do not have a bimodal
  distance of peak brightness as previously reported, but instead peak
  from 10.5 R <SUB>sun</SUB> to 14 R <SUB>sun</SUB> (prior to perihelion),
  suggesting there is a continuum of compositions rather than two
  distinct subpopulations. The light curves have two rates of brightening,
  typically vprop r <SUP>-7.3 ± 2.0</SUP> when first observed by SOHO
  (at distances of 30-35 R <SUB>sun</SUB>) then rapidly transitioning
  to vprop r <SUP>-3.8 ± 0.7</SUP> between 20 R <SUB>sun</SUB> and 30 R
  <SUB>sun</SUB>. It is unclear at what distance the steeper slope begins,
  but it likely does not extend much beyond the SOHO field of view. We
  derive nuclear sizes up to ~50 m in radius for the SOHO-observed comets,
  with a cumulative size distribution of N(&gt;R) vprop R <SUP>-2.2</SUP>
  for comets larger than 5 m in radius. This size distribution cannot
  explain the largest members of the family seen from the ground,
  suggesting that either the size distribution does not extend to the
  largest sizes or that the distribution is not uniform around the
  orbit. The total mass of the distribution up to the largest expected
  size (~500 m) is ~4 × 10<SUP>14</SUP> g, much less than the estimated
  masses of the largest ground-observed members. After correcting for
  the changing discovery circumstances, the flux of comets reaching
  perihelion has increased since 1996, and the increase is seen in
  comets of all sizes. Comparison of the SOHO comets with the Solwind
  and Solar Maximum Mission discoveries suggests there may have been an
  overabundance of bright comets arriving from 1979 to 1989, possibly
  indicative of a changing distribution around the Kreutz orbit.

---------------------------------------------------------
Title: Coronal Fine Linear Rays: Are They Fast Streams From Active
    Regions?
Authors: Koutchmy, Serge; Lamy, Philippe; Viladrich, Christian;
   Filippov, Boris; Nikoghossian, Arthur; Golub, Leon
2010AIPC.1216..339K    Altcode:
  Eclipse observations of the W-L corona show linear rays above active
  regions at times of solar maximum. We show that these linear rays are
  also observed in the field-of-view of the C2-LASCO coronagraph, in
  perfect correspondence with the eclipse results. A selected prominent
  case taken from the 2001 eclipse observation in Angola is analysed
  with several different methods, including the use of a synoptic map
  constructed using SoHO/LASCO C2 images. A clear signature of time
  variations near the eclipse observation is detected, suggesting that
  at least some parts of the beam are collimated. These observations
  strongly suggest high speed streams that apparently ignore the potential
  large scale coronal magnetic field rooted rather low in the corona. A
  possible origin is the neutral magnetic points located above the
  active region. Several mechanisms exist to explain how the plasma is
  accelerated in these regions to large quasi-relativistic velocities,
  possibly related to the occurrence of type III radio bursts. We point
  out a curious analogy with phenomena occurring inside coronal holes.

---------------------------------------------------------
Title: Properties of Comet Nuclei
Authors: Lamy, P. L.; Toth, I.; Fernandez, Y. R.; Weaver, H. A.
2010PDSS.8122E....L    Altcode:
  This data set presents tables 1, 2, 3, 4, 5 and 7 of 'Sizes, Shapes,
  Albedos, and Colors of Cometary Nuclei' (Lamy et al., 2004), and
  includes references for the sources cited. The authors culled this data
  from published or well-known unpublished sources, and have indicated
  what they judge to be the most reliable value available.

---------------------------------------------------------
Title: HiRISE Mission to Address the Dynamical Chromosphere-Corona
    Interface
Authors: Damé, Luc; Lamy, Philippe; von Fay-Siebenburgen Erdélyi,
   Robert
2010cosp...38.2844D    Altcode: 2010cosp.meet.2844D
  Several ground facilities and space missions are currently dedicated
  to the study of the Sun at high resolution and of the solar corona
  in particular. However, and despite significant progress with the
  advent of space missions and UV, EUV and XUV direct observations of
  the hot chro-mosphere and million degrees coronal plasma, much is yet
  to be achieved in the understanding of these high temperatures, fine
  dissipative structures and of the coronal heating in general. Recent
  missions have shown the definite role of waves and of the magnetic
  field deep in the inner corona, at the chromosphere-corona interface,
  where dramatic changes occur. The dynamics of the chromosphere and
  corona is controlled by the emerging magnetic field, guided by the
  coronal magnetic field. Accordingly, the direct measurement of the
  chromospheric and coronal magnetic fields is of prime importance. The
  solar corona consists of many thin loops or threads with the plasmas
  brightening and fading independently. The dynamics in each thread is
  believed to be related to the formation of filaments, each one being
  dynamic, in a non-equilibrium state. The mechanism sustaining that
  dynamics, oscillations or waves (Alfvén or MHD?), require both very
  high-cadence, multi-spectral observations, and high resolution. This
  is foreseen in the future Space Mission HiRISE, the ultimate new
  generation ultrahigh resolution, interferomet-ric and coronagraphic,
  Solar Physics Mission, proposed for ESA Cosmic Vision (pre-selected
  in 2007, and under preparation for 2012 second call). HiRISE (High
  Resolution Imaging and Spectroscopy Explorer), at the L1 Lagrangian
  point, provides meter class FUV imaging and spectro-imaging, EUV and
  XUV imaging and spectroscopy, and ultimate coronagraphy by a remote
  external occulter (satellites in formation flying 280 m apart) allowing
  to characterize temperature, densities and velocities in the solar upper
  chromosphere, transition zone and inner corona with, in particular, 2D
  very high resolution multi-spectral imaging-spectroscopy, direct coronal
  magnetic field measurement: a unique set of tools to understand the
  structuration and onset of coronal heating. We give a detail account
  of the proposed mission profile, major scien-tific objectives and
  model payload of HiRISE, a natural complement to the Solar Probe type
  missions lacking duty cycle, high resolution, spatial, spectral and
  temporal multi-temperature diagnostics and full coronal magnetometry.

---------------------------------------------------------
Title: ASPIICS / PROBA-3 formation flying externally-occulted giant
    coronagraph mission
Authors: Lamy, Philippe; Damé, Luc
2010cosp...38.1882L    Altcode: 2010cosp.meet.1882L
  During the time operation of the Helios mission, from 1974 to
  metricconverterProductID1986, a1986, a large number of magnetic clouds
  was identified by the magnetic field and solar wind sensors onboard
  the probes. Among these magnetic clouds, some of them were identified
  by at least two probes, provided that IMP-8 and ISEE-3 were monitoring
  the dayside magnetosphere. The magnetic cloud observed on from DOY 029
  to DOY 030/1977 by Helios 1, Helios 2, and IMP-8 represents a potential
  multi-spacecraft observed magnetic cloud. Despite the interaction with
  the high-speed stream that compressed the magnetic cloud, the minimum
  variance analysis technique showed the same direction of rotation of
  the magnetic field inside the magnetic cloud. This helped to associate
  the observation of the magnetic cloud at multi-spacecraft.

---------------------------------------------------------
Title: ASPIICS / PROBA-3: a formation flying externally-occulted
    giant coronagraph mission
Authors: Lamy, Philippe; Damé, Luc; Curdt, W.; Davila, J.; Defise,
   J. M.; Fineschi, S.; Heinzel, P.; Howard, R.; Kuzin, S.; Schmutz,
   W.; Tsinganos, K.; Turck-Chièze, S.; Zhukov, A.
2010cosp...38.2858L    Altcode: 2010cosp.meet.2858L
  Classical externally-occulted coronagraphs are presently limited in
  their performances by the distance between the external occulter and
  the front objective. The diffraction fringe from the occulter and
  the vignetted pupil which degrades the spatial resolution prevent
  useful observa-tions of the white light corona inside typically 2-2.5
  Rsun. Formation flying offers an elegant solution to these limitations
  and allows conceiving giant, externally-occulted coronagraphs
  us-ing a two-component space system with the external occulter on
  one spacecraft and the optical instrument on the other spacecraft
  at distances of hundred meters. Such an instrument has just been
  selected by ESA to fly (by the end of 2013) on its PROBA-3 mission,
  presently in phase B, to demonstrate formation flying. It will perform
  both high spatial resolution imaging of the solar corona as well as
  2-dimensional spectroscopy of several emission lines (in partic-ular
  the forbidden line of FeXIV at 530.285 nm) from the coronal base out
  to 3 Rsun using a Fabry-Perot interferometer. The classical design of
  an externally-occulted coronagraph is adapted to the formation flying
  configuration allowing the detection of the very inner corona as close
  as 0.05 Rsun from the solar limb. By tuning the position of the occulter
  spacecraft, it may even be possible to try reaching the chromosphere
  and the upper part of the spicules. ASPIICS/PROBA-3 mission, payload
  and scientific objectives are detailed.

---------------------------------------------------------
Title: Physical properties of asteroid 2867 Steins
Authors: Keller, Horst Uwe; Jorda, Laurent; Spjuth, Sofie; Lamy,
   Philippe; Groussin, Olivier; Schroder, Stefan; Marchi, Simone;
   Kueppers, Michael; Gaskell, Robert
2010cosp...38..632K    Altcode: 2010cosp.meet..632K
  ESA's spacecraft Rosetta passed the E-type asteroid 2867
  Steins on 5. Sept. 2009 on its way to a rendezvous with comet
  67P/Churyumov-Gerasimenko. The scientific camera system OSIRIS took
  several hundred images. The best resolution of 160 m (2 pixel) was
  achieved at a closest approach of 803 km. The images show an oblate body
  with an effective spherical diameter of 5.3 km. A large crater of 2.1
  km in diameter suggests that Steins is a rubble pile. Its conical shape
  could be the result of YORP spin-up. A lack of small craters indicates
  a rather recent resurfacing event. Disk resolved photometry based on a
  shape model constructed from trian-gular facets and using the formalism
  of Hapke (1993, 2002) constrains the surface properties. On its inbound
  leg the spacecraft passed near zero phase angle and the photometry of
  the op-position effect suggests that both shadow-hiding and coherent
  backscattering are present. The optically relevant regolith surface of
  Steins appears to be porous, consisting of fine transparent grains. The
  geometric albedo calculated from the Hapke parameters can be compared
  to the value derived directly from the images near zero phase angle.

---------------------------------------------------------
Title: Multi-spacecraft observation of a magnetic cloud
Authors: de Lucas, Aline; Dal Lago, Alisson; Schwenn, Rainer; Clúa de
   Gonzalez, Alicia L.; Marsch, Eckart; Lamy, Philippe; Damé, Luc; Curdt,
   W.; Davila, J.; Defise, J. M.; Fineschi, S.; Heinzel, P.; Howard, R.;
   Kuzin, S.; Schmutz, W.; Tsinganos, K.; Turck-Chièze, S.; Zhukov, A.
2010cosp...38.1921D    Altcode: 2010cosp.meet.1921D
  Classical externally-occulted coronagraphs are presently limited in
  their performances by the distance between the external occulter and
  the front objective. The diffraction fringe from the occulter and
  the vignetted pupil which degrades the spatial resolution prevent
  useful observa-tions of the white light corona inside typically 2-2.5
  Rsun. Formation flying offers an elegant solution to these limitations
  and allows conceiving giant, externally-occulted coronagraphs
  us-ing a two-component space system with the external occulter on
  one spacecraft and the optical instrument on the other spacecraft
  at distances of hundred meters. Such an instrument has just been
  selected by ESA to fly (by the end of 2013) on its PROBA-3 mission,
  presently in phase B, to demonstrate formation flying. It will perform
  both high spatial resolution imaging of the solar corona as well as
  2-dimensional spectroscopy of several emission lines (in partic-ular
  the forbidden line of FeXIV at 530.285 nm) from the coronal base out
  to 3 Rsun using a Fabry-Perot interferometer. The classical design of
  an externally-occulted coronagraph is adapted to the formation flying
  configuration allowing the detection of the very inner corona as close
  as 0.05 Rsun from the solar limb. By tuning the position of the occulter
  spacecraft, it may even be possible to try reaching the chromosphere
  and the upper part of the spicules. ASPIICS/PROBA-3 mission, payload
  and scientific objectives are presented.

---------------------------------------------------------
Title: Restitution of multiple overlaid components on extremely long
    series of solar corona images
Authors: Llebaria, A.; Loirat, J.; Lamy, P.
2010SPIE.7533E..0YL    Altcode: 2010SPIE.7533E..25L
  This contribution describes the methods used to accurately disentangle
  the components observed on a very large series of images of the solar
  corona. This series consists of 12 years of continuous observations
  provided by the LASCO/C2 coronagraph aboard SOHO (the SOlar and
  Heliospheric Observatory). Continuously centred on the Sun, which is
  masked, the observed images display a blend of many components. The
  more conspicuous are the K-corona from the coronal plasma, the F-corona
  from the coronal dust and the instrumental straylight. All of them are
  optically thin but in the LASCO/C2 field of view only the K-corona is
  polarized. The set of observations is composed of two huge series of
  images: the "polarization series" (at least one observation every day)
  and the "white light series" (more than 50 images every day). The goal
  is to determine quantitatively the evolution of each image component
  during the 12 years. Assuming 1) a small and slow temporal evolution
  for the F-corona and straylight, 2) the 2D regularity of the F-corona
  and 3) the ability to deduce the influence of the SOHO-Sun distance,
  the F-corona function is determined from the polarized series and
  afterwards subtracted of the white light series to obtain the K-corona
  white light series.

---------------------------------------------------------
Title: E-Type Asteroid (2867) Steins as Imaged by OSIRIS on Board
    Rosetta
Authors: Keller, H. U.; Barbieri, C.; Koschny, D.; Lamy, P.; Rickman,
   H.; Rodrigo, R.; Sierks, H.; A'Hearn, M. F.; Angrilli, F.; Barucci,
   M. A.; Bertaux, J. -L.; Cremonese, G.; Da Deppo, V.; Davidsson, B.;
   De Cecco, M.; Debei, S.; Fornasier, S.; Fulle, M.; Groussin, O.;
   Gutierrez, P. J.; Hviid, S. F.; Ip, W. -H.; Jorda, L.; Knollenberg,
   J.; Kramm, J. R.; Kührt, E.; Küppers, M.; Lara, L. -M.; Lazzarin,
   M.; Moreno, J. Lopez; Marzari, F.; Michalik, H.; Naletto, G.; Sabau,
   L.; Thomas, N.; Wenzel, K. -P.; Bertini, I.; Besse, S.; Ferri, F.;
   Kaasalainen, M.; Lowry, S.; Marchi, S.; Mottola, S.; Sabolo, W.;
   Schröder, S. E.; Spjuth, S.; Vernazza, P.
2010Sci...327..190K    Altcode:
  The European Space Agency’s Rosetta mission encountered the main-belt
  asteroid (2867) Steins while on its way to rendezvous with comet
  67P/Churyumov-Gerasimenko. Images taken with the OSIRIS (optical,
  spectroscopic, and infrared remote<SUP> </SUP>imaging system) cameras
  on board Rosetta show that Steins is an oblate body with an effective
  spherical diameter of 5.3 kilometers. Its surface does not show color
  variations. The morphology of Steins is dominated by linear faults
  and a large 2.1-kilometer-diameter crater near its south pole. Crater
  counts reveal a distinct lack of small craters. Steins is not solid
  rock but a rubble pile and has a conical appearance that is probably
  the result of reshaping due to Yarkovsky-O’Keefe-Radzievskii-Paddack
  (YORP) spin-up. The OSIRIS images constitute direct evidence for the
  YORP effect on a main-belt asteroid.

---------------------------------------------------------
Title: OASIS: a simulator to prepare and interpret remote imaging
    of solar system bodies
Authors: Jorda, L.; Spjuth, S.; Keller, H. U.; Lamy, P.; Llebaria, A.
2010SPIE.7533E..11J    Altcode: 2010SPIE.7533E..28J
  We present a new tool, called "OASIS" (Optimized Astrophysical Simulator
  for Imaging Systems), whose aim is to generate synthetic calibrated
  images of solar system bodies. OASIS has been developed to support the
  operations and the scientific interpretation of visible images acquired
  by the OSIRIS visible camera aboard the Rosetta spacecraft, but it
  can be used to create synthetic images taken by the visible imaging
  system of any spacecraft. OASIS allows takes as input the shape model
  of the object, in the form of triangular facets defining its surface,
  geometric parameters describing the position and orientation of the
  objects included in the scene and of the observer, and instrumental
  parameters describing the geometric and radiometric properties of the
  camera. The rendering of the object is performed in several steps which
  involve: (i) sorting the triangular facets in planes perpendicular
  to the direction of the light source and to the direction of the
  line-of-sight, (ii) tracing rays from a given facet to the light source
  and to the observer to check if it is illuminated and in view from
  the observer, (iii) calculating the intersection between the projected
  coordinates of the facets and the pixels of the image, and finally (iv)
  radiometrically calibrating the images. The pixels of the final image
  contain the expected signal from the object in digital numbers (DN). We
  show in the article examples of synthetic images of the asteroid (2867)
  Steins created with OASIS, both for the preparation of the flyby and
  for the scientific interpretation of the acquired images later on.

---------------------------------------------------------
Title: On the 3-D reconstruction of Coronal Mass Ejections using
    coronagraph data
Authors: Mierla, M.; Inhester, B.; Antunes, A.; Boursier, Y.; Byrne,
   J. P.; Colaninno, R.; Davila, J.; de Koning, C. A.; Gallagher, P. T.;
   Gissot, S.; Howard, R. A.; Howard, T. A.; Kramar, M.; Lamy, P.;
   Liewer, P. C.; Maloney, S.; Marqué, C.; McAteer, R. T. J.; Moran, T.;
   Rodriguez, L.; Srivastava, N.; St. Cyr, O. C.; Stenborg, G.; Temmer,
   M.; Thernisien, A.; Vourlidas, A.; West, M. J.; Wood, B. E.; Zhukov,
   A. N.
2010AnGeo..28..203M    Altcode:
  Coronal Mass ejections (CMEs) are enormous eruptions of magnetized
  plasma expelled from the Sun into the interplanetary space, over the
  course of hours to days. They can create major disturbances in the
  interplanetary medium and trigger severe magnetic storms when they
  collide with the Earth's magnetosphere. It is important to know their
  real speed, propagation direction and 3-D configuration in order to
  accurately predict their arrival time at the Earth. Using data from
  the SECCHI coronagraphs onboard the STEREO mission, which was launched
  in October 2006, we can infer the propagation direction and the 3-D
  structure of such events. In this review, we first describe different
  techniques that were used to model the 3-D configuration of CMEs in
  the coronagraph field of view (up to 15 R⊙). Then, we apply these
  techniques to different CMEs observed by various coronagraphs. A
  comparison of results obtained from the application of different
  reconstruction algorithms is presented and discussed.

---------------------------------------------------------
Title: PHYSICAL PROPERTIES OF STEINS' CRATERS
Authors: Besse, S.; Lamy, P. L.; Marchi, S.; Jorda, L.
2009AGUFM.P11C1235B    Altcode:
  The ROSETTA spacecraft, on its way to rendez-vous comet
  67P/Churyumov-Gerasimenko, has successfully flew by asteroid 2867
  Steins in September 2008. The OSIRIS experiment (Keller et al,
  2007) has imaged the asteroid both with the Wide Angle Camera (WAC)
  and the Narrow Angle Camera (NAC). The resolutions of the images are
  sufficient to distinguish features on the surface, especially craters
  which are detected all over the observed part of the asteroidal surface
  (44%). In this study, we focus on the physical properties of the craters
  and particularly theirs diameters and depths which we can compare with
  others small bodies previously observed. Starting from the first shape
  model of the asteroid (Besse et al, 2009), we add artificial craters
  that best match the observations and correlate the simulated images and
  the real images. The highest correlation yields the diameter and the
  depth of the craters. The average Depth/Diameter ratio for Steins is
  0.12. However, these values are quite heterogeneous and ranged from 0.04
  to 0.25. These results are in agreement with previous studies: 0.15 for
  Ida (Sullivan et al, 1996) and 0.14 for Gaspra (Carr et al,1994). The
  difference is likely due to the resurfacing of the surface by the large
  impact that occurs on the south pole of Steins with a diameter of 2100
  meters. Craters with extreme values of the Depth/Diameter ratio are
  located in the vicinity of this large crater and may be related to the
  large impact. Shallower craters could have been filled by ejecta or
  regolith displacement, while steeper craters could result from fault
  basin related to the impact or simply be recent events.

---------------------------------------------------------
Title: Spitzer observations of the asteroid-comet transition object
    and potential spacecraft target 107P (4015) Wilson-Harrington
Authors: Licandro, J.; Campins, H.; Kelley, M.; Fernández, Y.;
   Delbó, M.; Reach, W. T.; Groussin, O.; Lamy, P. L.; Toth, I.;
   A'Hearn, M. F.; Bauer, J. M.; Lowry, S. C.; Fitzsimmons, A.; Lisse,
   C. M.; Meech, K. J.; Pittichová, J.; Snodgrass, C.; Weaver, H. A.
2009A&A...507.1667L    Altcode: 2009arXiv0910.0116L
  Context: Near-Earth asteroid-comet transition object 107P/ (4015)
  Wilson-Harrington is a possible target of the joint European Space
  Agency (ESA) and Japanese Aerospace Exploration Agency (JAXA) Marco Polo
  sample return mission. Physical studies of this object are relevant
  to this mission, and also to understanding its asteroidal or cometary
  nature.<BR /> Aims: Our aim is to obtain significant new constraints on
  the surface thermal properties of this object.<BR /> Methods: We present
  mid-infrared photometry in two filters (16 and 22 μm) obtained with
  NASA's Spitzer Space Telescope on February 12, 2007, and results from
  the application of the Near Earth Asteroid Thermal Model (NEATM). We
  obtained high S/N in two mid-IR bands allowing accurate measurements
  of its thermal emission. <BR /> Results: We obtain a well constrained
  beaming parameter (η = 1.39±0.26) and obtain a diameter and geometric
  albedo of D = 3.46±0.32 km, and p<SUB>V</SUB> = 0.059±0.011. We also
  obtain similar results when we apply this best-fitting thermal model
  to single-band mid-IR photometry reported by Campins et al. (1995,
  P&amp;SS, 43, 733), Kraemer et al. (2005, AJ, 130, 2363) and Reach et
  al. (2007, Icarus, 191, 298).<BR /> Conclusions: The albedo of 4015
  Wilson-Harrington is low, consistent with those of comet nuclei and
  primitive C-, P-, D-type asteorids. We establish a rough lower limit
  for the thermal inertia of W-H of 60 Jm<SUP>-2</SUP>s<SUP>-0.5</SUP>
  K<SUP>-1</SUP> when it is at r = 1 AU, which is slightly over the
  limit of 30 Jm<SUP>-2</SUP> s<SUP>-0.5</SUP> K<SUP>-1</SUP> derived
  by Groussin et al. (2009, Icarus, 199, 568) for the thermal inertia
  of the nucleus of comet 22P/Kopff.

---------------------------------------------------------
Title: Tomography with LASCO-C2 Total Brightness Images
Authors: Frazin, R. A.; Llebaria, A.; Lamy, P. L.
2009AGUFMSH44A..08F    Altcode:
  The recently completed calibration of the K-corona total brightness
  (B) images from the SOHO/LASCO archive offers the opportunity for
  3D reconstruction of the corona's electron density from a vastly
  larger data set than is available from the polarized brightness (pB)
  images. Since the B has a different line-of-sight weighting than the pB,
  the two may be combined to provide more information than is available
  from either one (this fact has already been exploited to locate CME
  centers of mass), leading to better results. Here, we present the first
  tomography based on B images and compare the results to those based
  on pB images and the combination of pB and B images. Implications
  for time-dependent tomography and improved modeling the of F-corona
  are discussed.

---------------------------------------------------------
Title: Properties of the nuclei and comae of 13 ecliptic comets from
    Hubble Space Telescope snapshot observations
Authors: Lamy, P. L.; Toth, I.; Weaver, H. A.; A'Hearn, M. F.;
   Jorda, L.
2009A&A...508.1045L    Altcode:
  Context: Knowledge of the size distribution of cometary nuclei and, more
  generally, of their physical properties is important for constraining
  models of the formation and evolution of the Solar System. <BR /> Aims:
  We report on our on-going effort to determine the ensemble properties
  of comets based on our success in detecting the nuclei of active comets
  with the Hubble Space Telescope (HST). <BR /> Methods: During cycle
  8 (July 1999 to June 2000), we observed 13 ecliptic comets with the
  planetary camera 2 through at least two filters (V and R) and up to four
  (B, V, R, I) for the brightest ones. The ~30 min of HST observational
  time devoted to each comet did not permit a proper determination
  of light curves, so our “snapshot” observations yield effective
  radii, not shapes. <BR /> Results: Assuming spherical nuclei with a
  geometric albedo of 0.04 for the R band (except 0.024 for 10P/Tempel
  2, as independently measured) and a phase law of 0.04 mag/deg, we
  obtained the following effective radii: 4P/Faye: 1.77 km, 10P/Tempel
  2: 5.98 km, 17P/Holmes: 1.71 km, 37P/Forbes: 0.81 km 44P/Reinmuth 2:
  1.61 km, 50P/Arend: 0.95 km, 59P/Kearns-Kwee: 0.79 km, 63P/Wild 1:
  1.46 km, 71P/Clark: 0.68 km, 84P/Giclas: 0.90 km, 106P/Schuster:
  0.94 km, 112P/Urata-Niijima: 0.90 km, 114P/Wiseman-Skiff: 0.78 km. In
  our present sample, eight out of thirteen nuclei have sub-kilometer
  radii. The average color of the observed nuclei is (V-R) = 0.52±0.04,
  which is significantly redder than the Sun. We determined the dust
  activity parameter Afρ of their coma in the R band, and estimated the
  dust production rates. The average reflectivity gradient of the dust
  comae of six comets is S' [670,792 nm] = 15.2±2.3% per kÅ.<BR /> <P
  />Based on observations made with the NASA/ESA Hubble space telescope,
  obtained at Space Telescope Science Institute, which is operated by
  the Association of Universities for Research in Astronomy under NASA
  contract NAS 5-26555.

---------------------------------------------------------
Title: The Thermal Emission of Comet 8P/tuttle Nucleus as Observed
    with the Plateau de Bure Interferometer
Authors: Boissier, Jeremie; Bockelée-Morvan, D.; Groussin, O.; Biver,
   N.; Colom, P.; Crovisier, J.; Jorda, L.; Lamy, P.; Moreno, R.
2009DPS....41.2001B    Altcode:
  Measuring the thermal emission of cometary nuclei allows the
  determination of albedo-independent sizes for comets that are
  not visited by space probes. In the IR, the atmosphere makes such
  observations difficult from the ground, so that space telescopes
  (ISO, Spitzer) are frequently used to observe cometary nuclei. In
  the millimeter range, single dish observations are mainly sensitive
  to the dust coma. Interferometric measurements are required but
  restricted up to now to two cometary nuclei from the Oort cloud
  (Hyakutake, Hale-Bopp). <P />The Halley type comet 8P/Tuttle made
  a close approach to the Earth in January 2008 (geocentric distance
  of 0.25 AU). Previous studies suggested that its nucleus was large
  (7.8 km radius) and faintly active. As a result this comet was a
  good target for interferometric observations of its nucleus thermal
  emission at millimeter wavelengths. <P />8P/Tuttle was observed at
  240 GHz (1.25 mm) with the IRAM interferometer on the Plateau de Bure
  in January 2008. The thermal emission of the nucleus was detected and
  found to be lower than expected, corresponding to an apparent radius
  close to 2 km. Independant observations carried out with Hubble and
  Spitzer space telescopes indicate a slightly larger size (2.8 km
  radius) and were used to build a shape and thermal emission model of
  8P nucleus (Groussin et al., A&amp;A suubmitted). We used this model
  to interpret the Plateau de Bure data and we present here the results
  of this analysis. <P />Observations of cometary nuclei in millimeter
  interferometry will grow up in number in the forthcoming years with
  the upgrading of current instruments and the opening of ALMA. This
  will increase the sample of observed nuclei from all the comet dynamic
  classes and enable further studies of their physical properties.

---------------------------------------------------------
Title: Exploring Potential Surface Heterogeneity of the Asteroid
    Steins observed from the Rosetta OSIRIS Instrument
Authors: Leyrat, Cedric; Jorda, L.; Fornasier, S.; Fulchignoni,
   M.; Barucci, A.; Belskaya, I.; Lamy, P.; Groussin, O.; Charnoz, S.;
   Keller, H.; Sierks, H.; Hviid, S.; OSIRIS Team
2009DPS....41.5003L    Altcode:
  Asteroid 2867 Steins is the first E type asteroid visited by a
  spacecraft. During the Rosetta flyby in September 2008, the OSIRIS
  NAC and WAC cameras have obtained several disk-resolved images in
  visible wavelengths, at different phase angles. At closest approach,
  the spatial resolution of the WAC images was about 80m/pixel, allowing
  looking for potential surface heterogeneity. <P />We have applied the
  G-mode multivariate statistical method (Coradini et al, 1977) to both
  NAC and WAC images obtained around closest approach, at different
  wavelengths, from 295 to 986 nm. The geometric parameters have been
  retrieved with the SPICE routines. The shape of Steins is assumed to be
  represented by a polyhedron of almost 58000 facets. The OASIS simulator
  (developed at LAM and MPS) has been used to retrieve the I/F quantity
  of each visible 'facet' of the asteroid 3D shape model. Thereafter,
  photometric corrections have been performed using the Hapke (2002)
  model to eliminate the variable illuminations conditions at the
  surface. The G-mode classification method has been performed on a
  limited number of facets, in a region limited to [-50,+70] deg. in
  latitude and [-20,+90] deg. in longitude. <P />Moreover, a gravity
  map of the asteroid has been obtained on the basis of the shape model
  considering a homogeneous internal density. <P />Here we present our
  results on the potential presence of compositional heterogeneities at
  the surface of Steins and of gravitational anomalies, and we discuss
  their possible implications on the evolution of the asteroid.

---------------------------------------------------------
Title: The Physical Properties of Asteroid 2867 Steins
Authors: Lamy, Philippe L.; Jorda, L.; Gaskell, R.; Besse, S.;
   Groussin, O.; Kaasalainen, M.; OSIRIS Team
2009DPS....41.5901L    Altcode:
  We will present an overview of the physical properties of the E-type
  asteroid 2867 Steins from the OSIRIS campaign during the Rosetta flyby
  (September 2008), from ground-based observations, and from recent
  thermal spectroscopy obtained with the Spitzer space telescope. A
  complete shape solution has been obtained from the combination of
  resolved images and inversion of light curves. We will discuss the
  properties of the impact craters, the formation of the large crater and
  its consequences on topographic features and the possible influence
  of the YORP effect in shaping Steins. We will review and confront
  the various sources of information on the composition and surface
  photometric properties of Steins.

---------------------------------------------------------
Title: New perspective in solar coronal physics: Giant externally
    occulted coronagraphs using satellites in flight formation
Authors: Lamy, P.; Vivès, S.
2009AcAau..65..273L    Altcode:
  Formation flying opens new perspectives in solar physics, and
  allow to conceive giant, externally occulted coronagraphs using
  a two-component space system with the external occulter on one
  spacecraft and the optical instrument on the other spacecraft at a
  distance of 100 m. ASPIICS (Association de Satellites Pour l'Imagerie
  et l'Interférométrie de la Couronne Solaire) is a mission proposed
  to ESA in the framework of its PROBA-3 demonstration program of
  formation flying which is presently in phase A. ASPIICS is a single
  coronagraph which will perform both high spatial resolution imaging of
  the solar corona as well as two-dimensional spectroscopy of several
  emission lines from the coronal base out to 3R<SUB>⊙</SUB> using
  an étalon Fabry-Pérot interferometer. The classical design of an
  externally occulted coronagraph is adapted to the formation flying
  configuration allowing the detection of the very inner corona as close
  as 0.01R<SUB>⊙</SUB> from the solar limb. By tuning the position
  of the occulter spacecraft, it will even be possible to reach the
  chromosphere and the upper part of the spicules.

---------------------------------------------------------
Title: The ARTEMIS Catalog of LASCO Coronal Mass Ejections. Automatic
    Recognition of Transient Events and Marseille Inventory from
    Synoptic maps
Authors: Boursier, Y.; Lamy, P.; Llebaria, A.; Goudail, F.; Robelus, S.
2009SoPh..257..125B    Altcode:
  The LASCO-C2 coronagraph aboard the SOHO solar observatory has been
  providing a continuous flow of coronal images since 1996. Synoptic
  maps for each Carrington rotation have been built from these images,
  and offer a global view of the temporal evolution of the solar corona,
  particularly the occurrence of transient events. Coronal Mass Ejections
  (CMEs) present distinct signatures thus offering a novel approach to the
  problem of their identification and characterization. We present in this
  article an automated method of detection based on their morphological
  appearance on synoptic maps. It is based on adaptive filtering and
  segmentation, followed by merging with high-level knowledge. The
  program builds a catalog which lists the CMEs detected for each
  Carrington Rotation, together with their main estimated parameters:
  time of appearance, position angle, angular extent, average velocity
  and intensity. Our final catalog LASCO-ARTEMIS (Automatic Recognition
  of Transient Events and Marseille Inventory from Synoptic maps) is
  compared with existing catalogs, CDAW, CACTUS and SEEDS. We find that,
  likewise the automated CACTUS and SEEDS catalogs, we detect many more
  events than the CDAW catalog which is based on visual detection. The
  total number of detected CMEs strongly depends upon the sensitivity
  to small, faint and numerous events.

---------------------------------------------------------
Title: The colors of cometary nuclei—Comparison with other primitive
    bodies of the Solar System and implications for their origin
Authors: Lamy, P.; Toth, I.
2009Icar..201..674L    Altcode:
  We present new color results of cometary nuclei obtained with the
  Hubble Space Telescope (HST) whose superior resolution enables
  us to accurately isolate the nucleus signals from the surrounding
  comae. By combining with scrutinized available data obtained with
  ground-based telescopes, we accumulated a sample of 51 cometary nuclei,
  44 ecliptic comets (ECs) and 7 nearly-isotropic comets (NICs) using
  the nomenclature of Levison [Levison, H.F., 1996. In: Rettig, T.W.,
  Hahn, J.M. (Eds.), Completing the Inventory of the Solar System. In:
  ASP Conf. Ser., vol. 107, pp. 173-192]. We analyze color distributions
  and color-color correlations as well as correlations with other
  physical parameters. We present our compilation of colors of 232
  outer Solar System objects—separately considering the different
  dynamical populations, classical KBOs in low and high-inclination
  orbits (respectively CKBO-LI and CKBO-HI), resonant KBOs (practically
  Plutinos), scattered-disk objects (SDOs) and Centaurs—of 12 candidate
  dead comets, and of 85 Trojans. We perform a systematic analysis of all
  color distributions, and conclude by synthesizing the implications of
  the dynamical evolution and of the colors for the origin of the minor
  bodies of the Solar System. We find that the color distributions are
  remarkably consistent with the scenarios of the formation of TNOs
  by Gomes [Gomes, R.S., 2003. Icarus 161, 404-418] generalized by the
  "Nice" model [Levison, H.F., Morbidelli, A., VanLaerhoven, Ch., Gomes,
  R., Tsiganis, L., 2008. Icarus 196, 258-273], and of the Trojans
  by Morbidelli et al. [Morbidelli, A., Levison, H.F., Tsiganis, K.,
  Gomes, R., 2005. Nature 435, 462-465]. The color distributions of the
  Centaurs are globally similar to those of the CKBO-HI, the Plutinos
  and the SDOs. However the potential bimodality of their distributions
  allows to possibly distinguish two groups based on their (B-R) index:
  Centaur I with (B-R)&gt;1.7 and Centaurs II with (B-R)&lt;1.4. Centaurs
  I could be composed of TNOs (prominently CKBO-LI) and ultra red objects
  from a yet unstudied family. Centaurs II could consist in a population
  of evolved objects which have already visited the inner Solar System,
  and which has been scattered back beyond Jupiter. The diversity of
  colors of the ECs, in particular the existence of very red objects,
  is consistent with an origin in the Kuiper belt. Candidate dead comets
  represent an ultimate state of evolution as they appear more evolved
  than the Trojans and Centaurs II.

---------------------------------------------------------
Title: Three-Dimensional Kinematics of Coronal Mass Ejections from
    STEREO/SECCHI-COR2 Observations in 2007 - 2008
Authors: Boursier, Y.; Lamy, P.; Llebaria, A.
2009SoPh..256..131B    Altcode:
  We present a new method to perform the three dimensional
  characterization of coronal mass ejections (CMEs) using stereoscopic
  images obtained with the STEREO/SECCHI-COR2 coronagraphs. Two approaches
  are proposed, and each associated algorithm gives the trajectory of the
  CME and its kinematical properties (velocity and acceleration profiles)
  intended for space weather forecast. The first approach is based on
  forward modeling appropriate to the reconstruction of surfaces in
  an optically thin medium, and performs a local approximation of the
  observed CME by a hemispherical shell, thus tracking the leading edge
  of the event. The second approach is based on tracking the center
  of gravity of the radiance of the CME in the images. More than 16
  000 blind tests have been performed to assess the performance of
  each algorithm. For that purpose, we used three distinct libraries
  of simulated images of CMEs that correspond to three CME models:
  hemispherical shell, flux rope, and cloud-like. The two methods are
  applied to a set of CMEs observed in 2007 and 2008 by the SECCHI-COR2
  coronagraphs, and when possible, our results are compared to those
  already published. The determinations of the direction of propagation
  and of the velocity are generally found in good agreement.

---------------------------------------------------------
Title: Imaging Asteroid (2867) Steins with OSIRIS onboard Rosetta
Authors: Keller, H.; A'Hearn, M.; Angrilli, F.; Barbieri, C.; Barucci,
   A.; Bertaux, J.; Cremonese, G.; Davidson, B.; de Cecco, M.; Debei,
   S.; Fulle, M.; Groussin, O.; Gutierrez, P.; Hviid, S.; Ip, W.; Jorda,
   L.; Knollenberg, J.; Koschniy, D.; Kramm, J.; Kührt, E.; Küppers,
   M.; Lamy, P.; Lara, L.; Lopez Moreno, J.; Marzari, F.; Michalik,
   H.; Naletto, G.; Rickmann, H.; Rodrigo, R.; Sabau, L.; Sierks, H.;
   Thomas, N.; Wenzel, P.; Lazzarin, M.
2009AGUSM.P12A..02K    Altcode:
  The Optical, Spectroscopic, and Infrared Remote Imaging System OSIRIS
  observed the E-type asteroid (2867) Steins during the fly-by of ESA's
  Rosetta spacecraft. Observations over a large phase angle range (from
  near 0 to 140) by the scientific camera system OSIRIS revealed the
  illuminated hemisphere of the asteroid's diamond-like shaped body
  with a mean radius of 2.7 km and a projected surface at zero phase
  angle of 5.3 x 3.9 km2. A large crater (diameter 2 km) is evidence of
  an almost disastrous impact and implies that Steins is not a solid
  rock. More than 30 craters or crater-like features with diameters
  &gt; 150 m are identified. 7 round concavities are arranged along a
  line pointing radially away from the big impact crater. The shape and
  volume of asteroid Steins is derived from models based on the images
  of both OSIRIS cameras and earlier observations of the photometric
  light curves. Its resemblance to a spinning top suggests that it was
  influenced by the YORP effect making it the first optical observation
  of such a body. Analysis of the images provide the disk integrated
  albedo, reveal a strong opposition effect, and photometric properties
  of the surface showing very little variegation. Its very uniform,
  bright surface suggests that this asteroid is homogeneously formed
  out of the igneous (magmatic) minerals found in enstatite achondrite
  meteorites that are produced in melts requiring temperatures of more
  than 1000 C. Consequently (2867) Steins is a fragment of the interior
  of a large parent body.

---------------------------------------------------------
Title: Three-dimensional kinematics of coronal mass ejections from
    STEREO/SECCHI-COR2 observations in 2007-2008
Authors: Boursier, Y.; Lamy, P.; Llebaria, A.
2009EGUGA..1112760B    Altcode:
  We present a new method to perform the three dimensional
  characterization of coronal mass ejections (CMEs) using stereoscopic
  images obtained with the STEREO/SECCHI-COR2 coronagraphs. Two approaches
  are proposed, and each associated algorithms returns the trajectory
  of the CME and its kinematics properties (velocity and acceleration
  profiles) intended for space weather forecast. The first approach is
  based on forward modeling appropriate to the reconstruction of surfaces
  in an optically thin medium, and performs a local approximation
  of the observed CME by an hemispherical shell, thus tracking the
  leading edge of the event. The second approach is based on tracking
  the center of gravity of the radiance of the CME on the images. More
  than 16000 blind tests have been performed to assess the performances
  of each algorithm. For that purpose, we used three distinct libraries
  of simulated images of CMEs that correspond to three CME models:
  hemispherical shell, flux rope, and cloud-like. The two methods are
  applied to a set of CMEs observed in 2007 and 2008 by the SECCHI-COR2
  coronagraphs, and when possible, our results are compared to those
  already published. The determinations of the direction of propagation
  and of the velocity are generally found in good agreement.

---------------------------------------------------------
Title: The DynaMICCS perspective. A mission for a complete and
    continuous view of the Sun dedicated to magnetism, space weather
    and space climate
Authors: Turck-Chièze, S.; Lamy, P.; Carr, C.; Carton, P. H.;
   Chevalier, A.; Dandouras, I.; Defise, J. M.; Dewitte, S.; Dudok de Wit,
   T.; Halain, J. P.; Hasan, S.; Hochedez, J. F.; Horbury, T.; Levacher,
   P.; Meissonier, M.; Murphy, N.; Rochus, P.; Ruzmaikin, A.; Schmutz,
   W.; Thuillier, G.; Vivès, S.
2009ExA....23.1017T    Altcode: 2008ExA...tmp...42T
  The DynaMICCS mission is designed to probe and understand the dynamics
  of crucial regions of the Sun that determine solar variability,
  including the previously unexplored inner core, the radiative/convective
  zone interface layers, the photosphere/chromosphere layers and the
  low corona. The mission delivers data and knowledge that no other
  known mission provides for understanding space weather and space
  climate and for advancing stellar physics (internal dynamics)
  and fundamental physics (neutrino properties, atomic physics,
  gravitational moments...). The science objectives are achieved
  using Doppler and magnetic measurements of the solar surface,
  helioseismic and coronographic measurements, solar irradiance at
  different wavelengths and in-situ measurements of plasma/energetic
  particles/magnetic fields. The DynaMICCS payload uses an original
  concept studied by Thalès Alenia Space in the framework of the
  CNES call for formation flying missions: an external occultation of
  the solar light is obtained by putting an occulter spacecraft 150 m
  (or more) in front of a second spacecraft. The occulter spacecraft,
  a LEO platform of the mini sat class, e.g. PROTEUS, type carries
  the helioseismic and irradiance instruments and the formation flying
  technologies. The latter spacecraft of the same type carries a visible
  and infrared coronagraph for a unique observation of the solar corona
  and instrumentation for the study of the solar wind and imagers. This
  mission must guarantee long (one 11-year solar cycle) and continuous
  observations (duty cycle &gt; 94%) of signals that can be very weak
  (the gravity mode detection supposes the measurement of velocity
  smaller than 1 mm/s). This assumes no interruption in observation
  and very stable thermal conditions. The preferred orbit therefore is
  the L1 orbit, which fits these requirements very well and is also an
  attractive environment for the spacecraft due to its low radiation and
  low perturbation (solar pressure) environment. This mission is secured
  by instrumental R and D activities during the present and coming
  years. Some prototypes of different instruments are already built
  (GOLFNG, SDM) and the performances will be checked before launch on
  the ground or in space through planned missions of CNES and PROBA ESA
  missions (PICARD, LYRA, maybe ASPIICS).

---------------------------------------------------------
Title: ASPIICS, a giant externally occulted coronagraph for the
    PROBA-3 formation flying mission
Authors: Vivès, S.; Lamy, P.; Koutchmy, S.; Arnaud, J.
2009AdSpR..43.1007V    Altcode:
  Formation flying opens new perspectives for coronal physics, and
  allow to conceive giant, externally occulted coronagraphs using a
  two-component space system with the external occulter on one spacecraft
  and the optical instrument on the other spacecraft. ASPIICS (Association
  de Satellites Pour l'Imagerie et l'Interférométrie de la Couronne
  Solaire) is a mission proposed to ESA in the framework of the PROBA-3
  program of formation flying which is presently in phase A, to exploit
  this technique for coronal observations. ASPIICS is composed of a
  single coronagraph which performs high spatial resolution imaging of
  the corona as well as 2-dimensional spectroscopy of several emission
  lines from the coronal base out to 3 R<SUB>⊙</SUB>. The selected
  lines allow to address different coronal regions: the forbidden
  line of Fe XIV at 530.285 nm (coronal matter), Fe IX/X at 637.4 nm
  (coronal holes), HeI at 587.6 nm (cold matter). An additional broad
  spectral channel will image the white light corona so as to derive
  electron densities. The classical design of an externally occulted
  coronagraph is adapted to the detection of the very inner corona
  as close as 1.01 R<SUB>⊙</SUB> and the addition of a Fabry-Perot
  interferometer using a so-called " étalon". This paper is dedicated
  to the description of the optical design and its critical components:
  the entrance optics and the Fabry-Pérot interferometer. ASPIICS will
  address the question of coronal heating and of the role of waves by
  characterizing propagating fluctuations (waves and turbulence) in the
  solar wind acceleration region and by looking for oscillations in the
  intensity and Doppler shift of spectral lines. The combined imaging
  and spectral diagnostics capabilities available with ASPIICS will
  allow to map the velocity field of the corona both in the sky plane
  (directly on the images) and along the line-of-sight by measuring
  the Doppler shifts of emission lines. We will attempt to determine
  how the different components of the solar wind, slow and fast are
  accelerated. ASPIICS will observe the corona during the maximum of
  solar activity, insuring the detection of many Coronal Mass Ejections
  (CMEs). By rapidly alternating high resolution imaging and spectroscopy,
  CMEs will be thoroughly characterized. In addition, ASPIICS will attempt
  to characterize the topology of the magnetic field in the corona.

---------------------------------------------------------
Title: 3-Dimensional Reconstruction of Asteroid 2867 Steins
Authors: Besse, S.; Groussin, O.; Jorda, L.; Lamy, P.; Kaasalainen,
   M.; Gesquiere, G.; Remy, E.; OSIRIS Team
2009LPI....40.1545B    Altcode:
  The OSIRIS imaging experiment has imaged asteroid Steins. We have
  combined three methods to retrieve the shape: limbs, Point of Interest
  and light curves. The mean radius of Steins is 2.7 ± 0.3km, for a
  volume of 78 ± 30km^3 and a surface of 98 ± 25km^2.

---------------------------------------------------------
Title: The size and thermal properties of the nucleus of Comet
    22P/Kopff
Authors: Groussin, O.; Lamy, P.; Toth, I.; Kelley, M.; Fernandez, Y.;
   A'Hearn, M.; Campins, H.; Licandro, J.; Lisse, C.; Lowry, S.; Meech,
   K.; Snodgrass, C.
2009Icar..199..568G    Altcode:
  We detected the nucleus of Comet 22P/Kopff at 4.87 AU from the Sun with
  the two IRS peak-up cameras of the Spitzer Space Telescope on April
  19, 2007. Using the thermal model of [Groussin, O., and 15 colleagues,
  2007. Icarus 187, 16-25], we derive a nucleus size of 1.89±0.16 km, in
  agreement with [Lamy, P., Toth, I., Jorda, L., Groussin, O., A'Hearn,
  M.F., Weaver, H.A., 2002. Icarus 156, 442-455], and a thermal inertia
  I⩽30 JKms.

---------------------------------------------------------
Title: Separation of limb and terminator on apparent contours of
    solar system small bodies
Authors: Llebaria, A.; Jorda, L.; Groussin, O.; Gesquiere, G.; Lamy, P.
2009SPIE.7246E..10L    Altcode: 2009SPIE.7246E..29L
  Segmentation of contours and silhouettes is a recurrent topic in image
  recognition and understanding. In this paper we describe a new method
  used to divide in two parts (the limb and the terminator) the apparent
  silhouette of an irregular astronomical body illuminated by a unique
  source, the Sun. One of the main objectives of the asteroids and comets
  flyby is the detailed 3D reconstruction of such bodies. However the
  number of images obtained during a flyby is limited, as well as the
  number of viewing geometries. In the 3D reconstruction we must consider
  not only the camera motion but also the free rotation of the body. The
  local brightness variations in the image vary with the rotation of the
  body and with the changing body-camera distance. The topography at the
  surface of the body can vary from very smooth to highly chaotic. In
  the shape from silhouette 3D reconstruction methods, limb profiles are
  used to retrieve the visual hull of the body. It is therefore required
  to be able to separate the limb profiles from the terminator ones. In
  this communication, we present a new method to perform this task based
  on the local measurement of the contour smoothness, which we define
  here as "activity". Developed in the framework of the Rosetta mission
  our method has been tested on a large set of asteroid and comet images
  taken during interplanetary missions. It looks robust to magnification
  and enlightenment changes

---------------------------------------------------------
Title: Disk-Resolved Photometry of 9P/Tempel 1 and 2867 Steins
Authors: Laurent, Jorda; Spjuth, S.; Keller, H.; Lamy, P.; OSIRIS Team
2009DPS....40.2837L    Altcode: 2009BAAS...41..559L
  Disk-resolved photometric properties of asteroids have been obtained
  on a sample of objects observed by space missions since the 80's. We
  have developed a method to retrieve such properties from images
  acquired by imaging instruments aboard spacecrafts. <P />We applied
  the method to images of the nucleus of comet 9P/Tempel 1 acquired by
  the DEEP IMPACT HRI camera, and we derived both local and global Hapke
  parameters for the comet nucleus, as well as its geometric albedo. The
  results have been compared to those obtained by Li et al. (Icarus 191,
  161, 2007). We will also present very preliminary results on asteroid
  2867 Steins observed by OSIRIS, the imaging system aboard ROSETTA,
  after its flyby on Sept. 5, 2008.

---------------------------------------------------------
Title: Asteroid 21 Lutetia : UBVRI Light Curves from OSIRIS-NAC
Authors: Faury, Guillaume; Jorda, L.; Lamy, P.; Kaasalainen, M.;
   Mottola, S.; OSIRIS Team
2009DPS....40.2838F    Altcode: 2009BAAS...41..559F
  We report on new observations aimed at characterizing asteroid 21
  Lutetia, one of the targets of the Rosetta space mission. The asteroid
  was imaged with the OSIRIS-NAC camera during the cruise phase of the
  Rosetta spacecraft, at a phase angle of 22.36º, and was continuously
  monitored over 14 hr (on 2 and 3 January 2007), thus covering one
  rotational period and a half. From accurate photometric calibrations
  with the solar analog star, 16 CygB, we have obtained high quality
  light curves of 21 Lutetia in the U, B, V, R and I photometric bands. We
  confirm a sidereal period of 8.17 hr. No spectral variations with the
  rotation have been found. The resulting reflectivity spectrum is in
  a very good agreement with that of Barucci et al. (2005). Combining
  with existing observations, we have obtained its phase function.

---------------------------------------------------------
Title: First Results from the Rosetta Asteroid Steins Fly-by Observed
    by OSIRIS and VIRTIS
Authors: Keller, Horst Uwe; Coradini, A.; Barbieri, C.; Koschny, D.;
   Lamy, P.; Rickman, H.; Rodrigo, R.; Capaccioni, F.; Drossart, P.;
   De Sanctis, M. C.; Arnold, G.; OSIRIS Science Team; VIRTIS Science Team
2009DPS....40.6010K    Altcode: 2009BAAS...41..564K
  On Sep 5<SUP>th</SUP> 2008 the ESA Rosetta spacecraft made a close
  fly-by of the E-type asteroid (2867) Steins. During the fly-by the
  asteroid was observed with the OSIRIS camera system and the VIRTIS
  infrared imaging spectrometer. OSIRIS is composed of a wide-angle (100um
  resolution) imager and a narrow angle (18.7um resolution) imager. VIRTIS
  is an instrument that combines imaging and spectrometry in the Vis
  and IR (0.25-5um), through a slit spectrometer(VIRTIS-M) with a high
  resolution IR channel (VIRTIS-H). <P />Rosetta passed through zero
  phase angle shortly before CA provided the opportunity to determine the
  geometric albedo and the phase function of the asteroid. High spatial
  resolution hyperspectral images were obtained by VIRTIS. The high
  albedo of the E-type asteroid is confirmed. The spectrum of Steins was
  observed using a complement of 23 OSIRIS filters from 245 to 1000 nm
  and VIRTIS spectra. The spectrum is in good agreement with published
  telescopic spectra in the visible and shows a strong drop off in the
  UV below 400 nm. <P />Images around CA show the asteroid surface on a
  scale of 80 m per pixel. The dimensions of Steins are 4.0 km along its
  spin axis and 5.9 km in the perpendicular direction. A shape model will
  be presented. The appearance of the body is dominated by a large crater
  (diameter 2 km) at the northern pole. From there a chain of 7 craters
  (catenae) extends across the surface visible during the fly-by. More
  than 20 craters with diameters &gt; 0.2 km can be counted. First results
  of a photometric model based on detailed topography are expected.

---------------------------------------------------------
Title: Rosetta Fly-by of Asteroid 2867 Steins: Phase Function from
    the OSIRIS Imaging System
Authors: Hviid, Stubbe; Fornasier, S.; Vernazza, P.; Sierks, H.;
   Keller, U.; Sabolo, W.; Kueppers, M.; Ferri, F.; Da Deppo, V.;
   Barbieri, C.; Lamy, P.; Jorda, L.; Groussin, O.; Koschny, D.;
   OSIRIS Team
2009DPS....40.2834H    Altcode: 2009BAAS...41..558H
  The ESA Rosetta mission performed a fly-by of the E-type asteroid Steins
  on September 5, 2008. The geometry of the fly-by was optimized to reach
  the zero phase angle aspect a couple of minutes before the closest
  approach. A fast monitoring sequence was implemented to investigate the
  phase function of the asteroid in the narrowband OI filter, centered
  at 630 nm, with the Wide Angle Camera of the OSIRIS imaging system. A
  set of 21 images of 30 ms exposure time were acquired for monitoring
  the opposition surge in the phase angle range from 0 to 11 degrees with
  a step of 0.5-1 degrees. In addition, several OI images were taken in
  the spectrophotometric sequences allowing us to reach a phase function
  coverage up to 140 degrees. In this work we present the Steins phase
  function and its interpretation. The derived values of the albedo,
  of the linear slope, and of the Hapke G parameter match those of E
  class asteroids.

---------------------------------------------------------
Title: Shape, Rotational Properties and Phase Function of Asteroid
    2867 Steins
Authors: Lamy, Philippe L.; Kaasalainen, M.; Jorda, L.; Gutierrez,
   P.; Faury, G.; Sabolo, W.; OSIRIS Team
2009DPS....40.2833L    Altcode: 2009BAAS...41..558L
  The Optical, Spectroscopic, and Infrared Remote Imaging System OSIRIS
  observed the E-type asteroid (2867) Steins during the fly-by of ESA's
  Rosetta spacecraft. Before the flyby, the OSIRIS camera obtained
  two light curves on 20 August and 4 September 2008. Combined with
  previously published OSIRIS and ground-based observations, we will
  present a refined global shape model of the asteroid, the rotational
  parameters and the phase function (at large phase angles).

---------------------------------------------------------
Title: Spitzer Space Telescope observations of the nucleus of comet
    67P/Churyumov-Gerasimenko
Authors: Lamy, P. L.; Toth, I.; Groussin, O.; Jorda, L.; Kelley,
   M. S.; Stansberry, J. A.
2008A&A...489..777L    Altcode:
  Context: Comet 67P/Churyumov-Gerasimenko is the target of the Rosetta
  mission, and an early characterization of its nucleus is required
  to assist in preparing the orbital strategy of the spacecraft, the
  delivery of the Philae surface module and the science operations. We
  detected the nucleus using the Hubble Space Telescope in March 2003,
  but had to assume an albedo to derive its size from its observed
  magnitudes. <BR />Aims: It is important to derive an additional
  constraint for independently determining both the comet size and
  albedo. <BR />Methods: We implemented the well-known “radiometric
  method”, which combines visible and infrared photometry. Sixteen
  thermal images of 67P/C-G were obtained by the Multiband Imaging
  Photometer (MIPS) 24 μm channel of the Spitzer Space Telescope (SST)
  on 25 February 2004: the observations spanned a time interval of ~12.5
  h, which sampled the rotational light curve of its nucleus. The comet
  was then outbound at a heliocentric distance of 4.48 AU, at a distance
  of 4.04 AU from SST, and at a solar phase angle of 12.1°. The nucleus
  conspicuously appeared as a bright point source superimposed on a dust
  trail; it was necessary to apply the point-spread function fitting
  technique using an adequate model of the trail to correctly determine
  the thermal flux from the nucleus. The data were analyzed using a
  standard thermal model that incorporated the thermal inertia. <BR
  />Results: Our preferred solution with a low thermal inertia has overall
  dimensions measured along the principal axis of 4.40-5.20 km, 4.16-4.30
  km, and 3.40-3.50 km, corresponding to an effective radius of a sphere
  with the same volume in the range of 1.93-2.03 km. Larger values of
  thermal inertia produce larger sizes but the effective radius cannot
  exceed ~2.3 km. The albedo is in the range 0.039-0.043, remarkably
  consistent with the canonical value of 0.04 for cometary nuclei. The
  success of the landing of the Philae surface module remains critically
  dependent upon the bulk density of the nucleus: it would be safe if
  close to 0.35 g cm<SUP>-3</SUP>, but a larger value, for instance 0.5
  g cm<SUP>-3</SUP>, would present some risks. <P />Based on observations
  made with the NASA Spitzer Space Telescope.

---------------------------------------------------------
Title: The Rosetta Asteroid Steins Flyby Observed by OSIRIS
Authors: Keller, Horst Uwe; Barbieri, C.; Koschny, D.; Lamy, P.;
   Rickman, H.; Rodrigo, R.; OSIRIS Team
2008DPS....40.2831K    Altcode: 2008BAAS...40..442K
  The Optical, Spectroscopic, and Infrared Remote Imaging System OSIRIS
  was already used to observe the light curve of the E-type asteroid
  (2867) Steins in preparation of the ESA Rosetta flyby (Küppers et
  al. A&amp;A 2007). During the approach observations of the light curve
  will be repeated to improve the knowledge about the rotational status,
  coarse shape, and phase of Steins. The closest approach (CA) campaign
  will start 2 hours before CA when the spacecraft is still 60000 km
  away from the asteroid. Changes of the reflectivity while passing
  through zero phase angle shortly before CA will be recorded taking
  images as fast as possible. The wide angle camera (WAC) will be used
  to search for satellites. Boulders as small as 10 cm in diameter can
  be detected in the large field of view. The narrow angle camera (NAC)
  will concentrate to observe the properties of Steins determining its
  shape and surface morphology. Near CA at a distance of 800 km images
  of Steins will cover about 330 pixel in diameter out of the 2k by 2k
  pixel CCD. We will report on the topography and geomorphology based
  on a derived digital terrain model. Photometric properties and phase
  angle variations will be determined over taking advantage of the
  varying observation geometry. Both cameras will use a complement of
  23 filters between 245 to 1000 nm.

---------------------------------------------------------
Title: Asteroid 2867 Steins. I. Photometric properties from
    OSIRIS/Rosetta and ground-based visible observations
Authors: Jorda, L.; Lamy, P. L.; Faury, G.; Weissman, P.; Barucci,
   M. A.; Fornasier, S.; Lowry, S.; Toth, I.; Küppers, M.
2008A&A...487.1171J    Altcode:
  Context: Asteroid 2867 Steins is the first target of the Rosetta space
  mission with a flyby scheduled in September 2008. <BR />Aims: An early
  characterization is needed to optimize the flyby parameters and the
  science operations and to maximize the scientific return. The aim of
  this article is to characterize the photometric properties of this
  asteroid. <BR />Methods: The asteroid was imaged with the Narrow Angle
  Camera (NAC) of the Optical, Spectroscopic, and Infrared Remote Imaging
  System (OSIRIS) during the cruise phase of the Rosetta spacecraft,
  at a phase angle of 41.7° significantly larger than achievable from
  Earth. It was continuously monitored over ~24 h (on 11 March 2006), thus
  covering four rotational periods, at a temporal cadence of 6 min. An
  accurate photometric calibration was obtained from the observations of
  a solar analog star, 16 Cyg B. <BR />Results: The light curve in the R
  photometric band of the Johnson-Kron-Cousins system has a mean value
  R(1,1,α = 41.7° = 14.13 ± 0.03 and an amplitude of 0.25 ± 0.04
  mag. The periodicity was analyzed with different techniques yielding a
  mean value of the synodic rotational period of 6.054 ± 0.003 h. By
  combining with ground-based observations obtained at different phase
  angles, the phase function is constructed and characterized by a
  linear part having a phase coefficient β = 0.025 ± 0.001 mag/deg and
  a mean value R(1,1,0) = 13.10 ± 0.04. In terms of the H-G formalism,
  the best fit photometric values are G = 0.35 ± 0.05 and H = 12.84 ±
  0.07, but the resulting opposition surge of 0.25 mag, although typical
  of E-type asteroids, is not really constrained because of the lack of
  data at phase angles below 7°. Altogether the photometric properties
  of asteroid 2867 Steins (phase function, color and albedo) indicate
  that it is a somewhat extreme E-type object, although it is known that
  this quite small population exhibits at least three different surface
  mineralogies. <P />Table [see full textsee full text] is only available
  in electronic form at http://www.aanda.org

---------------------------------------------------------
Title: Asteroid 2867 Steins. III. Spitzer Space Telescope
    observations, size determination, and thermal properties
Authors: Lamy, P. L.; Jorda, L.; Fornasier, S.; Groussin, O.; Barucci,
   M. A.; Carvano, J.; Dotto, E.; Fulchignoni, M.; Toth, I.
2008A&A...487.1187L    Altcode:
  Context: Asteroid 2867 Steins is the first target of the Rosetta
  space mission with a flyby scheduled in September 2008. <BR />Aims:
  An early characterization is needed to optimize the flyby parameters
  and the science operations, and to maximize the scientific return. <BR
  />Methods: We used the infrared spectrograph (IRS) of the Spitzer Space
  Telescope (SST) to obtain 14 spectra ranging from 5.2 to 38.0 μm, and
  to sample the rotational period of the asteroid. The observations were
  performed on 22 November 2005, when the asteroid was 2.13 AU from the
  Sun, 1.60 AU from the SST, and at a phase angle of 27.2°. They were
  interpreted using a standard thermal model incorporating the thermal
  inertia. <BR />Results: The solution for a spherical shape leads to an
  effective radius r<SUB>n</SUB> = 2.46 ± 0.20 km and a thermal inertia
  I = 150 ± 60 J K<SUP>-1</SUP> m<SUP>-2</SUP> s<SUP>-1/2</SUP>, for
  a beaming factor between 0.8 and 1.0. The geometric albedo is then
  constrained by visible photometry to p<SUB>R</SUB> = 0.31 ± 0.05 and
  p<SUB>V</SUB> = 0.27 ± 0.04 when using a linear phase function. The
  H-G phase law, which includes an opposition effect, leads to larger
  values of the albedo, p_R(H-G) = 0.40 ± 0.07 and p_V(H-G) = 0.34
  ± 0.06. The solution for our 3-dimensional shape model has overall
  dimensions of 5.73 ± 0.52 × 4.95 ± 0.45 × 4.58 ± 0.41 km.

---------------------------------------------------------
Title: Hubble Space Telescope Observations of Fragment C of the
    Split Comet 73p/schwassmann-wachmann 3 in 2001 and 2006
Authors: Toth, Imre; Lamy, P. L.; Weaver, H. A.; Noll, K. S.; Mutchler,
   M. J.
2008DPS....40.0508T    Altcode: 2008BAAS...40..394T
  We unambiguously detected fragment C of the split comet
  73P/Schwassmann-Wachmann 3 on 26 November 2001 with the PC2 and on 10
  April 2006 with the HRC of the ACS of the HST. On 26 November 2001
  it was at heliocentric and geocentric distances respectively 3.26
  AU and 2.34 AU and despite of its large heliocentric distance it was
  highly active and from images obtained during two consecutive orbits
  we determined an effective radius of 0.68±0.04 km assuming a spherical
  shape and standard values for the geometric albedo (0.04) and the phase
  function (0.04 mag/deg) (Icarus 178, 235-247, 2005). We re-observed
  fragment C in 2006, taking advantage of the exceptional close encounter
  of the comet with Earth. The heliocentric and geocentric distances
  were respectively 1.24 AU and 0.29 AU. Six HST orbits spread over 21
  hrs allowed us to obtain multi-color images (BVR) but only a poorly
  sampled light curve. We determined a possible synodic rotational period
  in the range 3.5-4 hr. The mean magnitude of the light curve leads to an
  effective radius of 0.53±0.02 km for the fragment C (assuming the same
  standard values for the albedo and phase function) and its amplitude,
  to a minimum axial ratio of 1.8±0.3. Our deep exposures did not reveal
  any subfragment in the vicinity of the main C fragment. We will discuss
  possible scenarios to explain the decrease of the size of the C fragment
  which apparently took place between 2001 and 2006. Moreover, we will
  discuss a scenario to explain the increase of the rotational period of
  the C fragment which apparently took place between our HST observations
  and the radar observations (BAAS 38, abstr. 12.06, p. 504, 2006) about
  one month later. H,A,W. acknowledges supports by NASA through grant
  GO/10625 from the STScI, I.T. acknowledges support from CNES, France.

---------------------------------------------------------
Title: Photometry of the Kreutz Comets 1996-2005
Authors: Knight, Matthew M.; A'Hearn, M. F.; Biesecker, D. A.; Faury,
   G.; Hamilton, D. P.; Lamy, P.; Llebaria, A.
2008DPS....40.1601K    Altcode: 2008BAAS...40Q.411K
  We present the results of our photometric study of the Kreutz group
  of sungrazing comets observed by SOHO-LASCO from 1996-2005. We extend
  the work of Biesecker et al. (2002), expanding the sample from 141
  to more than 900 comets. The Kreutz comets seen by SOHO are produced
  by fragmentation from the more massive members of the family which
  include Ikeya-Seki (C/1965 S1 = 1965f) and C/1882 R1. None of the SOHO
  observed Kreutz comets have survived perihelion due to both their small
  size (we infer sizes less than 50 meters in radius) and perihelion
  distances below 2 solar radii. <P />Kreutz comets typically brighten
  at a rate near r<SUP>-7.3</SUP> when first entering the SOHO field of
  view (at distances near 30 solar radii), then rapidly transition to
  brightening at a rate near r<SUP>-3.8</SUP> from 16-24 solar radii. We
  find that they do not have a bimodal distance of peak brightness
  as previously reported by Biesecker et al. (2002), but instead
  peak between 10-14 solar radii, suggesting there is a continuum,
  perhaps due to compositional variations, rather than two distinct
  subpopulations. Inside of 10 solar radii but prior to perihelion, the
  comets fade rapidly and disappear by 6 solar radii. <P />We derive
  nuclear sizes of up to 50 meters in radius, with a cumulative size
  distribution of N(&gt;R) R<SUP>-2.2</SUP> for comets larger than 5
  meters in radius. This size distribution cannot explain the six largest
  members of the family seen from the ground, suggesting that either the
  family is not collisionally evolved or that the distribution is not
  uniform around the orbit. The total mass of the distribution up to the
  largest expected size ( 500 meters) is 4x10<SUP>14</SUP> g, much less
  than the estimated mass of the largest ground observed members. <P
  />This research was supported by NASA Planetary Atmospheres grants
  NAG513295 and NNG06GF29G.

---------------------------------------------------------
Title: Spitzer Space Telescope Observations of the Nucleus of Comet
    8P/Tuttle
Authors: Groussin, Olivier; Kelley, M.; Lamy, P.; Toth, I.; Fernandez,
   Y.; Jorda, L.; Weaver, H.
2008DPS....40.0503G    Altcode: 2008BAAS...40..393G
  We observed comet 8P/Tuttle, a nearly isotropic comet (NIC), with the
  IRS and MIPS instruments of the Spitzer Space Telescope (SST). The
  IRS observations were performed on 2 November 2007 when the comet
  was at 1.32 AU from SST, 1.61 AU from the Sun, and nearly 3 months
  before perihelion on 27 January 2008 when its heliocentric distance
  was 1 AU. We used IRS in low-resolution mode to obtain the spectral
  energy distribution (SED) from 5 to 35 micron. The MIPS observations
  were performed on 22 June 2008 when the comet was at 1.58 AU from SST
  and 2.24 AU from the Sun. We sampled a period of 15 hours with 20 MIPS
  images at 24 µm, and also acquired 4 MIPS images at 70 µm to better
  constrain the SED. From these IRS and MIPS observations, we derived
  the size and thermal inertia of the nucleus of comet 8P/Tuttle. The
  (010-000) vibrational emission band of water at 6.3 microns was also
  detected, and we derived the water production rate and active surface
  fraction.

---------------------------------------------------------
Title: Asteroid 2867 Steins. II. Multi-telescope visible observations,
    shape reconstruction, and rotational state
Authors: Lamy, P. L.; Kaasalainen, M.; Lowry, S.; Weissman, P.;
   Barucci, M. A.; Carvano, J.; Choi, Y. -J.; Colas, F.; Faury, G.;
   Fornasier, S.; Groussin, O.; Hicks, M. D.; Jorda, L.; Kryszczynska,
   A.; Larson, S.; Toth, I.; Warner, B.
2008A&A...487.1179L    Altcode:
  Context: Asteroid 2867 Steins is the first target of the Rosetta space
  mission with a flyby scheduled in September 2008. <BR />Aims: An early
  physical characterization is needed to optimize the flyby parameters
  and the science operations, and to maximize the scientific return. The
  aim of this article is to characterize the shape and rotational state
  of this asteroid. <BR />Methods: We compile a set of 26 visible light
  curves whose phase angle coverage extends from 7.5° to 41.7°, and
  perform their simultaneous inversion relying on convex modeling. <BR
  />Results: The full three-dimensional solution for asteroid 2867
  Steins is rather spherical with axial ratios a/b=1.17 and a/c=1.25. The
  rotational state is characterized by a sidereal period of 6.04681 ±
  0.00002 h, and the pole direction defined by its ecliptic coordinates
  λ ≈ 250° and β ≈ - 89° has an uncertainty of about 5°. It is
  therefore almost exactly perpendicular to the ecliptic plane, and the
  viewing geometries are thus restricted to only ±20° about Steins'
  equator. Consequently, the shape model is not strongly constrained,
  and the polar flattening has an uncertainty of about 10%. Inversion is
  basically scale-free, and absolute scaling comes from a measurement
  of its thermal emission with the Spitzer Space Telescope (Lamy et
  al. 2008, A&amp;A, 487, 1187), yielding overall dimensions of 5.73 ±
  0.52, 4.95±0.45, and 4.58 ± 0.41 km.

---------------------------------------------------------
Title: Hubble Space Telescope Observations of the Nucleus of Comet
    8P/Tuttle
Authors: Lamy, Philippe L.; Toth, I.; Jorda, L.; Weaver, H. A.;
   Groussin, O.; A'Hearn, M. F.
2008DPS....40.0502L    Altcode: 2008BAAS...40..393L
  We unambiguously detected the nucleus of comet 8P/Tuttle, a
  nearly-isotropic comet (NIC) in a 13.5 yr orbital period, during its
  recent close (0.25 AU) Earth encounter with the Planetary Camera 2 of
  the Hubble Space Telescope (HST). <P />The observations were performed
  from December 10.0 to 11.2, 2007, and consisted in 12 visits extending
  over a 28-hour period. At the mid-point of the observing window, the
  comet was 1.25 AU from the Sun , 0.48 AU from the Earth and at a phase
  angle of 46.6 deg. During each visit corresponding to an HST orbit,
  typically twelve images were obtained through five broadband filters
  (UBVRI). The light curve exhibits a complex shape best modeled by
  a bilobate body as evidenced by the radar observations of Harmon
  et al. (2008). We determined a synodic rotational period of 11.4
  hr. Assuming the same albedo of 0.04 for the two lobes, we found
  respective radii of 1.2 km and 2.8 km. During the HST observations,
  the nucleus was at an aspect angle (between spin axis and line of sight)
  of 65 deg.

---------------------------------------------------------
Title: 3-Dimensional Reconstruction of the ROSETTA Targets -
    Application to Asteroid 2867 Steins
Authors: Besse, Sebastien; Groussin, O.; Jorda, L.; Lamy, P.;
   OSIRIS Team
2008DPS....40.2830B    Altcode: 2008BAAS...40..442B
  The OSIRIS imaging experiment aboard the Rosetta spacecraft will
  image asteroids Steins in September 2008 and Lutetia in 2010, and
  comet 67P/Churyumov-Gerasimenko in 2014. An accurate determination
  of the shape is a key point for the success of the mission operations
  and scientific objectives. Based on the experience of previous space
  missions (Deep Impact, Near, Galileo, Hayabusa), we are developing
  our own procedure for the shape reconstruction of small bodies. We use
  two different techniques : i) limb and terminator constraints and ii)
  ground control points (GCP) constraints. The first method allows the
  determination of a rough shape of the body when it is poorly resolved
  and no features are visible on the surface, while the second method
  provides an accurate shape model using high resolution images. We
  are currently testing both methods on simulated data, using and
  developing different algorithms for limb and terminator extraction
  (e.g.,wavelet), detection of points of interest (Harris, Susan,
  Fast Corner Detection), points pairing using correlation techniques
  (geometric model) and 3-dimensional reconstruction using line-of-sight
  information (photogrammetry). Both methods will be fully automated. We
  will hopefully present the 3D reconstruction of the Steins asteroid
  from images obtained during its flyby. <P />Acknowledgment: Sébastien
  Besse acknowledges CNES and Thales for funding.

---------------------------------------------------------
Title: In-orbit calibration of the polarization flat fields of the
    SOHO-LASCO coronagraphs
Authors: Llebaria, A.; Lamy, P.
2008SPIE.7010E..1IL    Altcode: 2008SPIE.7010E..46L
  Since 11 years SOHO-LASCO coronagraphs are producing a unique set of
  the Sun corona images in the 2-32 solar radius range. For the first
  time a complete set of coronal calibrated images in WL (polarized and
  unpolarized) for the full solar cycle is available. The telescopes are
  equipped with 3 polarizers at -60,0 and 60 degrees, one all pass channel
  and a set filters. Ground calibrations were completed with in orbit
  calibrations. To control the evolution of sensivity for each bandpass
  and for each polarizer, the LASCO-C2 and LASCO-C3 coronographs were
  provided with an internal system of calibration in orbit. The measures
  obtained in 1996 and 2003 have been used to determine the CCD flat field
  for each filter bandpass, the gain constant (ADU to phe<SUP>-</SUP>
  conversion) and the polarizers transmittance map. The solar corona
  itself was also used to control the local response. Spacecraft rotations
  by 45 and 90 complete the test, and allowed for a ultimate but relevant
  global correction of the polarized images.

---------------------------------------------------------
Title: In-flight validation of the formation flying technologies
    using the ASPIICS/PROBA-3 giant coronagraph
Authors: Vivès, S.; Lamy, P.; Levacher, P.; Venet, M.; Boit, J. L.
2008SPIE.7010E..3RV    Altcode: 2008SPIE.7010E.109V
  Classical externally-occulted coronagraphs are presently limited in
  their performances by the distance between the external occulter and
  the front objective. Formation flyers open new perspectives and allow
  conceiving giant, externally-occulted coronagraphs using two-spacecraft
  system. The PROBA-3 formation flying demonstration mission, currently
  in its preparatory study phase, is intended to incorporate the ASPIICS
  (Association de Satellites Pour l'Imagerie et l'Interfromtrie de la
  Couronne Solaire) scientific payload. ASPIICS is a solar coronagraph
  designed to observe from the coronal base out to 3 solar radii with high
  spatial resolution in the visible range. Formation flying technique
  imposes new constraints and major challenges in particular in terms
  of metrology. ASPIICS will both use and demonstrate the formation
  flying features and performances. In order to fully validate the
  formation flying technique and to improve the scientific return,
  original developments linked to the formation flying constraints have
  been made these last years and are presented in this article.

---------------------------------------------------------
Title: The coronal dynamics imagers for the KuaFu mission
Authors: Vives, S.; Lamy, P.; Rousset, G.; Boit, J. L.
2008AdSpR..42..106V    Altcode:
  The Space Weather Explorer - KuaFu mission will provide simultaneous,
  long-term, and synoptic observations of the complete chain of
  disturbances from the solar atmosphere to the geospace. KuaFu-A
  (located at the L1 liberation point) includes Coronal Dynamics Imagers
  composed of a Lyman-α coronagraph (from 1.15 to 2.7 solar radii)
  and a white light coronagraph (out to 15 solar radii), in order to
  identify the initial sources of Coronal Mass Ejections (CMEs) and
  their acceleration profiles. The difficulty of observing the lower
  corona should not be underestimated since instrumental stray light
  remains a critical issue in the visible because of the low contrast
  of the corona with respect to the Sun. Observing the corona in the
  Lyman-α line is a valid alternative to white light observations. This
  approach takes advantage of both the intrinsic higher contrast of
  the corona with respect to the solar disk in this line compared to
  the visible, and the absence of F-corona at 121.6 nm. Furthermore,
  it has been convincingly shown that the coronal structures seen in
  Lyman-α correspond to those seen in the visible and which result from
  Thomson scattering of the coronal ionized gas. This is because the
  plasma is still collisional in the lower corona so that the hydrogen
  neutral atoms are coupled to the protons. A classical, all-reflecting
  internally-occulted Lyot coronagraph is required so as to preserve the
  image quality down to the inner limit of the field-of-view. A narrow
  band interference filter located in a collimated beam allows isolating
  the Lyman-α line. The visible coronagraph will adopt the approach of a
  single instrument having a large field-of-view extending from 2.5 to 15
  solar radii. Such a design is based on refractive externally-occulted
  coronagraphs built for recent past missions, essentially the LASCO-C2
  and C3 instruments and the SECCHI/COR 2 of the STEREO mission, which
  is itself a combination of the C2 and C3 instruments.

---------------------------------------------------------
Title: Comet 144P/KUSHIDA
Authors: Kelley, M. S.; Fernandez, Y.; Weaver, H.; Toth, I.; Reach,
   W.; Pittichova, J.; Meech, K.; Lowry, S.; Lisse, C.; Licandro, J.;
   Lamy, P.; Groussin, O.; Fitzsimmons, A.; Campins, H.; Bauer, J.;
   A'Hearn, M.; Marsden, B. G.
2008MPEC....N...20K    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Comet Observations [245 Spitzer Space Telescope]
Authors: Kelley, M. S.; Fernandez, Y.; Weaver, H.; Toth, I.; Reach, W.;
   Pittichova, J.; Meech, K.; Lowry, S.; Lisse, C.; Licandro, J.; Lamy,
   P.; Groussin, O.; Fitzsimmons, A.; Campins, H.; Bauer, J.; A'Hearn, M.
2008MPC..63320..13K    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: New perspectives in solar coronagraphy offered by formation
flying: from PROBA-3 to Cosmic Vision
Authors: Lamy, P.; Vivès, S.; Damé, L.; Koutchmy, S.
2008SPIE.7010E..1HL    Altcode:
  Formation flying opens new perspectives in solar physics, and allow to
  conceive giant, externally-occulted coronagraphs using a two-component
  space system with the external occulter on one spacecraft and the
  optical instrument on the other spacecraft at a distance of hundred
  meters. Conditions close to those of a solar total eclipse can then be
  achieved offering the capability of imaging the solar corona down to the
  limb at very high spatial resolution. ASPIICS (Association de Satellites
  Pour l'Imagerie et l'Interférométrie de la Couronne Solaire) is a
  mission proposed to ESA in the framework of its PROBA-3 demonstration
  program of formation flying which is presently in phase A. ASPIICS is
  a single coronagraph which will perform both high spatial resolution
  imaging of the solar corona as well as 2-dimensional spectroscopy of
  several emission lines from the coronal base out to 3 R\beye using
  a Fabry-Pérot étalon interferometer. The classical design of an
  externally-occulted coronagraph is adapted to the formation flying
  configuration allowing the detection of the very inner corona as
  close as 0.01 R\beye from the solar limb. Super-ASPIICS is an even
  more ambitious instrument part of the scientific payload of HiRise,
  the High Resolution Imaging and Spectroscopy Explorer proposed to
  ESA in the framework of its Cosmic Vision program. With an increased
  inter-satellite distance of 280 m, an aperture of 300 mm, a spectral
  domain extending from the ultraviolet to the near-infrared, and
  spectroscopic capabilities, Super-ASPIICS will offer unprecedented
  diagnostic capabilities, including the measurement of coronal magnetic
  fields.

---------------------------------------------------------
Title: The Origin of Polar Streamers in the Solar Corona
Authors: Zhukov, A. N.; Saez, F.; Lamy, P.; Llebaria, A.; Stenborg, G.
2008ApJ...680.1532Z    Altcode:
  We investigate the large-scale three-dimensional (3D) structure of the
  solar corona near the maximum of the 23rd solar cycle in an attempt to
  determine the origin of polar streamers. We use a model that allows
  us to simulate the quasi-stationary configuration of the large-scale
  coronal density distribution. The coronal neutral line, as given by
  the potential field source surface (PFSS) model, serves as a proxy for
  mid- and low-latitude current sheets. We investigate the contribution
  of possible polar coronal current sheets associated with large-scale
  photospheric magnetic neutral lines around the poles of the Sun (polar
  crown neutral lines). Positions of polar neutral lines are radially
  extrapolated outward to obtain the configuration of polar current
  sheets. Coronal plasma sheets are centered around introduced current
  sheets. Streamer positions during Carrington rotation 1965, near the
  activity maximum, are calculated. Simulated synoptic maps of the coronal
  brightness are compared with those obtained from observations by the
  LASCO C2 coronagraph on board the SOHO spacecraft. We demonstrate that
  polar streamers are "classical" streamers situated above low-lying loops
  (observed by SOHO EIT) connecting the regions of opposite magnetic
  polarity on two sides of polar crown neutral lines. Polar streamer
  configurations obtained from our model are close to those observed
  by LASCO. Our results suggest that the PFSS model cannot adequately
  describe the configuration of streamers during the epoch of high solar
  activity. The representation of the streamer belt as a single tilted
  and warped current sheet becomes questionable. Multiple coronal current
  sheets may better correspond to the observed streamer configurations.

---------------------------------------------------------
Title: Results From SEPPCoN, a Survey to Study the Physical Properties
    of the Nuclei and Dust of Jupiter-Family Comets
Authors: Fernandez, Y.; Kelley, M.; Lamy, P.; Reach, W.; Toth,
   I.; Groussin, O.; Lisse, C.; A'Hearn, M.; Bauer, J.; Campins, H.;
   Fitzsimmons, A.; Licandro, J.; Lowry, S.; Meech, K.; Pittichova, J.;
   Snodgrass, C.; Weaver, H.
2008AGUSM.P41A..08F    Altcode:
  We present results from SEPPCoN, our Survey of Ensemble Physical
  Properties of Cometary Nuclei. This survey involves studying 100
  Jupiter-family comets (JFCs) -- about 30% of the known population
  -- at both mid-infrared and visible wavelengths. We have used the
  Spitzer Space Telescope to study the comets' thermal emission, and
  many ground-based telescopes (Apache Point's ARC 3.5-m; ESO's NTT
  3.6-m; MKO's UH 2.2-m and Keck 10-m; Palomar's 5-m and 1.5-m; ORM's
  WHT 4.2-m, NOT 2.6-m, and LT 2-m; Cerro Pachon's SOAR 4.1-m) to study
  the reflected sunlight. The Spitzer observations (imaging with IRS PU
  and MIPS) are complete, and the ground-based observations (imaging
  in at least R band) are about half complete. Almost all our targets
  are imaged while farther than 4 AU from the Sun, to minimize (and
  often eliminate) confusion caused by dust from cometary activity. The
  Spitzer data constrain the effective radii of the nuclei; we find
  preliminarily that the cumulative size distribution's power-law slope
  is similar to what has been found by others using visible wavelength
  studies, suggesting that there is no strong trend of albedo with
  size. The Spitzer data also tell us about the thermal inertia, and we
  find that many -- though not all -- cometary nuclei seem to have low
  values of this, consistent with a porous, fluffy, poorly-conducting,
  dusty surface layer. The Spitzer images show that about one-third of
  our sample appeared with extended dust emission despite being close to
  aphelion. We find that often the activity observed at these distances
  seems to turn off abruptly once a JFC passes aphelion. We have used
  dynamical analysis to constrain the dust grain sizes and thereby
  distinguish dust tails from dust trails. The dust temperatures are in
  most cases consistent with isothermal, low-albedo grains in LTE. We
  thank the Spitzer Science Center and the TACs of the aforementioned
  telescopes for supporting this research.

---------------------------------------------------------
Title: A Portrait of Asteroid 2867 Steins from Visible and Infrared
    Observations with Ground- and Space-Based Telescopes
Authors: Lamy, P. L.; Barucci, A.; Fornasier, S.; Groussin, O.; Jorda,
   L.; Kaasalainen, M.; Lowry, S.; Toth, I.
2008LPICo1405.8163L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Solar cycle evolution of the magnetic topology of the corona
    as deduced from Lasco-C2
Authors: Llebaria, Antoine; Lamy, Philippe; Saez, Fabien
2008cosp...37.1812L    Altcode: 2008cosp.meet.1812L
  The magnetic topology of the corona is clearly revealed by the
  structures in the corona. Its temporal evolution can therefore
  be analyzed using synoptic maps of the polarized radiance pB of
  the K-corona or the derived electron densities. In January 2008,
  the LASCO-C2 coronagraph aboard SOHO has completed 12 years of
  quasi-continuous observations of the solar corona from 2 to 6 solar
  radii, thus allowing a full view of the evolution of the magnetic
  topology over a full solar cycle. From this data set, we have produced
  synoptic maps of of unsurpassed spatial and temporal resolutions. The
  periodic sampling (2 x 14 days) of this series best shows the global
  evolution of the whole corona. The onset of the Sun activity period is
  clearly marked by increasing twists of the neutral sheet, shifting the
  activity to higher and higher latitudes. The neutral sheet then splits
  into two or more oscillating branches branches characterized by long
  oscillating periods. Surprisingly this situation prevails until the
  end of the present 23rd cycle. Short scale variations have also been
  analyzed and will be discussed.

---------------------------------------------------------
Title: Hubble Investigation of the B and G Fragments of Comet
    73P/Schwassmann-Wachmann 3
Authors: Weaver, H. A.; Lisse, C. M.; Mutchler, M.; Lamy, P. L.;
   Toth, I.; Reach, W. T.; Vaubaillon, J.
2008LPICo1405.8248W    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Kuiper Belt Objects in the Planetary Region: The Jupiter-Family
    Comets
Authors: Lowry, S.; Fitzsimmons, A.; Lamy, P.; Weissman, P.
2008ssbn.book..397L    Altcode:
  Jupiter-family comets (JFCs) are a dynamically distinct group with
  low orbital inclinations and orbital periods ó20 yr. Their origin
  has been shown computationally to be the Kuiper belt region beyond
  Neptune. Therefore studying the nuclei of these comets, as well as
  their coma species, can provide valuable insights into the nature of
  the kilometer-sized Kuiper belt objects (KBOs). These include their
  size distribution, internal structure, and composition, as well as some
  hints at their likely surface features. Although JFCs are much closer
  to the Sun than KBOs, they are still very difficult to observe due to
  their intrinsic faintness and outgassing comae. However, observational
  studies are advancing rapidly and we are now starting to place valuable
  constraints on the bulk physical properties of these nuclei. In this
  chapter, we review some of the more important findings in this field
  and their relevance to KBO studies.

---------------------------------------------------------
Title: A Portrait of Asteroid 21 Lutetia from Visible and Infrared
    Observations with Ground- and Space-Based Telescopes
Authors: Lamy, P. L.; Barucci, A.; Fornassier, S.; Faury, G.; Groussin,
   O.; Kaasalainen, M.; Jorda, L.; Mottola, S.; Toth, I.
2008LPICo1405.8245L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Determination of Photometric Properties of Asteroid Steins
Authors: Spjuth, S.; Jorda, L.; Li, J.; Keller, H. U.; Kueppers, M.;
   Hviid, S.; Lamy, P.
2008LPICo1405.8082S    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Asteroids 2867 Steins and 21 Lutetia: surface composition
    from far infrared observations with the Spitzer space telescope
Authors: Barucci, M. A.; Fornasier, S.; Dotto, E.; Lamy, P. L.; Jorda,
   L.; Groussin, O.; Brucato, J. R.; Carvano, J.; Alvarez-Candal, A.;
   Cruikshank, D.; Fulchignoni, M.
2008A&A...477..665B    Altcode:
  Aims:The aim of this paper is to investigate the surface composition of
  the two asteroids 21 Lutetia and 2867 Steins, targets of the Rosetta
  space mission. <BR />Methods: We observed the two asteroids through
  their full rotational periods with the Infrared Spectrograph of the
  Spitzer Space Telescope to investigate the surface properties. The
  analysis of their thermal emission spectra was carried out to
  detect emissivity features that diagnose the surface composition. <BR
  />Results: For both asteroids, the Christiansen peak, the Reststrahlen,
  and the Transparency features were detected. The thermal emissivity
  shows a clear analogy to carbonaceous chondrite meteorites, in
  particular to the CO-CV types for 21 Lutetia, while for 2867 Steins,
  already suggested as belonging to the E-type asteroids, the similarity
  to the enstatite achondrite meteorite is confirmed.

---------------------------------------------------------
Title: Comet Dust and Activity in the SEPPCoN Survey
Authors: Kelley, M. S.; Fernández, Y. R.; A'Hearn, M. F.; Bauer, J.;
   Campins, H.; Fitzsimmons, A.; Groussin, O.; Lamy, P. L.; Licandro,
   J.; Lisse, C. M.; Lowry, S. C.; Meech, K. J.; Pittichová, J.; Reach,
   W. T.; Snodgrass, C.; Toth, I.; Weaver, H. A.
2008LPICo1405.8272K    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Coronal electron density over a full solar cycle - Implications
    for the solar wind velocity
Authors: Lamy, Philippe
2008cosp...37.1687L    Altcode: 2008cosp.meet.1687L
  In January 2008, the LASCO-C2 coronagraph aboard SOHO has completed
  12 years of quasicontinuous observations of the solar corona from
  2 to 6 solar radii, that is over a full solar cycle. We study the
  temporal evolution of the electron density derived from the calibrated
  pB images over this unsurpassed time span, first globally, and then
  by distinguishing different latitude intervals so as to characterize
  the the equatorial and polar regions. The local density moderately
  increases with activity (factor 2), as the bulk of the increase
  essentially results from the development of new sources associated to
  emerging neutral or current sheets. We extensively study different
  typical structures of the corona, polar and trans-equatorial holes
  and the streamer belt to constrain the velocity profiles of different
  regimes of solar wind. Finally we combine LASCO-C2 density profiles,
  SWAN mass flux data and interplanetary solar wind velocities derived
  from ground-based Interplanetary Scintillation Observations (IPS) to
  conclude that the fast solar wind reaches its terminal velocity about 6
  solar radii, and expands with constant velocity beyond this distance,
  while the slow solar wind reaches only half its terminal velocity
  value at this distance and thus continues its acceleration further out.

---------------------------------------------------------
Title: Three-dimensional reconstruction of Coronal Mass Ejections
    using STEREO/SECCHI-COR2 and SoHO/LASCO-C2 data.
Authors: Boursier, Yannick; Lamy, Philippe; Saez, Fabien; Llebaria,
   Antoine
2008cosp...37..361B    Altcode: 2008cosp.meet..361B
  We present a new method to perform the three-dimensional reconstruction
  of CMEs using stereoscopic images obtained with the STEREO/SECCHI-COR2
  coronagraph, as well as images from the SoHO/LASCO-C2 and C3
  coronagraphs. Our algorithm is based on a forward modeling approach
  appropriate to the reconstruction of surfaces in optically thin
  medium. It involves four main steps : i) definition of three distinct
  geometrical and representative models of CMEs (spherical shell,
  fluxrope, cloud-like), ii) generation of a library of simulated images,
  iii) local approximation of the observed CME by a sphere shell for a
  first estimate of the parameters, iv) determination of the model in
  the library that best fits the observed CME . The comparison between
  simulated and observed images is based on purely geometrical criteria
  and geometric invariants. The algorithm provides two estimates of
  the direction of propagation, an estimate of the velocity profile,
  and the set of parameters which define the shape and the orientation
  of the CME for space weather forecast. Uncertainties on the direction
  of propagation are derived from error measurement on the images. We
  have applied our algorithm to a set of CMEs observed in 2007, and
  when possible, our results are compared with those coming from the
  Geometric Localization Method (Pizzo and Biesecker, 2004 ; de Koning,
  C. A.; Pizzo, V. J.; Biesecker, D. A., 2007). Finally an identification
  of the source regions have been performed.

---------------------------------------------------------
Title: The Size, Thermal Inertia and Water Production Rate of Comet
    8P/Tuttle
Authors: Groussin, O.; Kelley, M. S.; Fernández, Y. R.; Jorda, L.;
   Lamy, P. L.; Toth, I.; Weaver, H. A.
2008LPICo1405.8035G    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Phase Angle Effects on Sungrazing Comets Observed by SOHO
Authors: Knight, M. M.; A'Hearn, M. F.; Biesecker, D. A.; Faury, G.;
   Hamilton, D. P.; Lamy, P.; Llebaria, A.
2008LPICo1405.8143K    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Solar Astrophysics, Interferometry, and Coronagraphy at
    DomeC/Concordia
Authors: Damé, L.; Amans, J. -P.; Dournaux, J. -L.; Koutchmy, S.;
   Lamy, P.; Preumont, A.
2008EAS....33..105D    Altcode:
  Excellent seeing, coronal conditions, and very low IR thermal
  background are qualities of the Dome C/Concordia station site that
  will allow unique solar astrophysics science. We review the science
  case for inner corona observations (onset of the coronal heating
  mechanism still poorly understood) and the promises of high angular
  resolution to disentangle the possible mechanisms at work between
  waves, convection, and reconnection in this particularly magnetically
  structured solar atmosphere between the high chromosphere and inner
  corona. For coronagraphy, IR and high resolution possibilities, Dome
  C is a case by itself between classical ground-based sites and space
  opportunities. Telescopes from 50 cm (coronagraphy oriented) to 4 m
  (full high resolution advantage including IR access) are proposed to
  benefit from these remarkable observing capabilities. Using 3×O50
  cm off-axis telescopes, we first propose a medium size facility
  (1.4 m equivalent telescope) for very high resolution access, ADSIIC
  (Antarctica Demonstrator of Solar Interferometric Imaging &amp;
  Coronagraphy), before the ultimate 9-telescope Solar Facility
  equivalent to a 4 m diameter telescope: A-FOURMI (Antarctica 4 m
  Interferometer). Finally, 30 m tower designs and their logistics using
  standard containers and elementary elements of 6 m maximum length,
  are presented and discussed. These towers are indeed of general
  interest also for the other optical and IR telescopes intended for
  Dome C/Concordia, allowing to get over most of the turbulent ground
  layer and to reach the best possible permanent seeing conditions
  (better than half an arcsec).

---------------------------------------------------------
Title: Three-dimensional structure of white light polar Plumes at
    the beginning and at the end of Solar Cycle 23
Authors: Boursier, Yannick; Llebaria, Antoine; Lamy, Philippe
2008cosp...37..362B    Altcode: 2008cosp.meet..362B
  In spite of a large set of observations from spatial instruments, the
  3D structure of polar plumes remains an open question. Even if the
  connection between plumes observed in the EUV and WL seems globally
  established, their dynamics and the one-to-one relationship remains
  unclear. We first examine and compare high cadence observations obtained
  in March 1997 and in March 2006 by the well know method of sinogram,
  and find a pronounced similarity. We then implement a forward model,
  introducing a fractal distribution of the electron density, and
  show that it provides a better agreement to the observations than
  classical models such as curtains or columns of plasma, at least from
  the geometric and photometric points of view.

---------------------------------------------------------
Title: Results from SEPPCoN, A Survey of Ensemble Physical Properties
    of Cometary Nuclei
Authors: Fernández, Y. R.; Kelley, M. S.; Lamy, P. L.; Toth,
   I.; Groussin, O.; A'Hearn, M. F.; Bauer, J. M.; Campins, H.;
   Fitzsimmons, A.; Licandro, J.; Lisse, C. M.; Lowry, S. C.; Meech,
   K. J.; Pittichová, J.; Reach, W. T.; Snodgrass, C.; Weaver, H. A.
2008LPICo1405.8307F    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Characterization of the Nucleus Fragment
    73P/Schwassmann-Wachmann 3-C from Hubble Space Telescope Observation
    in 2001 and 2006
Authors: Lamy, P. L.; Toth, I.; Weaver, H. A.; Noll, K. S.
2008LPICo1405.8160L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Commission 21: Light of the Night Sky
Authors: Gustafson, Bo A. S.; Witt, Adolf N.; Lamy, Philippe; Dwek,
   Eli; Lamy, Philippe; Henry, Richard C.; Mann, Ingrid
2007IAUTB..26..138G    Altcode:
  Applications have been received from Dr. Peter Wheatley (proposed by
  UK), Prof. Harald Schuh (proposed by Austria), and Dr. Busaba Kramer
  (proposed by Thailand). All applications were endorsed, with the caveat
  that Dr. Kramer's application needs to be endorsed by at least one
  of the other commissions since she has not a publication record in
  our field.

---------------------------------------------------------
Title: Recent Evolution of the Kracht Group of Comets
Authors: Knight, Matthew M.; A'Hearn, M. F.; Biesecker, D. A.; Faury,
   G.; Hamilton, D. P.; Lamy, P.; Llebaria, A.
2007AAS...211.8504K    Altcode: 2007BAAS...39Q.877K
  The Kracht group contains 29 comets discovered in SOHO images from
  1996-2005 with perihelion distances of 7-11 solar radii and inclinations
  of 12-15 degrees. Unlike the much more populous Kreutz sungrazing group,
  many Kracht comets are observed to survive perihelion, and as many as
  five may have been observed on two apparitions, with periods ranging
  from 4.8-5.8 years. Kracht comets tend to arrive in clusters followed
  by many months devoid of comets before another cluster arrives. Ohtsuka
  et al. (2003) and Sekanina and Chodas (2005) have shown that the Kracht
  group represents an evolutionary stage of the Machholz complex, which
  has evolved over many centuries and also includes 96P/Machholz 1,
  the Marsden group of comets, the Daytime Arietids, and the Southern
  delta Aquarids. <P />Here we explain the recent evolution of individual
  members of the Kracht group as a series of cascading fragmentations
  of a few large comets (causing the temporal clusters) which have
  had somewhat different orbital histories since splitting from each
  other within the last hundred years or so (causing the gaps between
  temporal clusters). We use dynamical simulations to search for possible
  fragmentation scenarios and to estimate the rate at which the orbital
  elements evolve due to the gravitational influence of the planets. We
  predict that 8 of the 19 fragments seen since 2002 may be observable
  in upcoming perihelion passages, including five that should reappear
  before the end of 2008. If observed, two of these will have been seen
  at three perihelion passages, allowing a rough estimation of the mass
  loss due to erosion. <P />This research was supported by NASA Planetary
  Atmospheres grant NNG06GF29G.

---------------------------------------------------------
Title: Results From SEPPCoN, a Survey to Study the Physical Properties
    of the Nuclei and Dust of Jupiter-Family Comets
Authors: Fernandez, Yanga R.; Kelley, M. S.; Lamy, P. L.; Reach,
   W. T.; Toth, I.; Groussin, O.; Lisse, C. M.; A'Hearn, M. F.; Bauer,
   J. M.; Campins, H.; Fitzsimmons, A.; Licandro, J.; Lowry, S. C.;
   Meech, K. J.; Pittichova, J.; Weaver, H. A.
2007AAS...211.5602F    Altcode: 2007BAAS...39..827F
  We present results from SEPPCoN, our Survey of Ensemble Physical
  Properties of Cometary Nuclei. This survey involves studying 100
  Jupiter-family comets (JFCs) -- about 30% of the known population --
  using the Spitzer Space Telescope for mid-infrared measurements
  of thermal emission and several ground-based telescopes for
  visible-wavelength measurements of reflected sunlight. The Spitzer
  observations (imaging with IRS PU and MIPS) are complete, and the
  ground-based observations (imaging in at least R band) are about half
  complete. Almost all our targets are imaged while farther than 4 AU
  from the Sun, to minimize (and often eliminate) confusion caused by
  dust from cometary activity. The Spitzer data constrain the effective
  radii of the JFC nuclei and thus give us an independent measurement
  of the cumulative size distribution (CSD). We find preliminarily that
  the CSD power-law slope is similar to what has been found by others
  using visible wavelength studies, suggesting that there is no strong
  trend of albedo with size. The Spitzer data also tell us about the JFC
  thermal inertia, and we find that many -- though not all -- cometary
  nuclei seem to have low values of this, consistent with a porous,
  fluffy, poorly-conducting, dusty surface layer. To our surprise,
  the Spitzer images show that about one-third of our sample appeared
  with extended dust emission despite being close to aphelion, and
  in many cases the dust originated from cometary activity happening
  right then. Interestingly, we find that the activity observed at
  these distances seems to turn off rather abruptly once a JFC passes
  aphelion. We have used dynamical analysis to constrain the dust grain
  sizes and thereby distinguish dust tails from dust trails. The dust
  temperatures are in most cases consistent with isothermal, low-albedo
  grains in LTE. We thank the Spitzer Science Center for supporting
  this research.

---------------------------------------------------------
Title: Velocity Profiles in the Solar Corona from Multi-Instrument
    Observations
Authors: Quémerais, E.; Lallement, R.; Koutroumpa, D.; Lamy, P.
2007ApJ...667.1229Q    Altcode: 2007arXiv0706.1913Q
  We present a method to derive outflow velocities in the solar corona
  using different data sets, including solar wind mass flux coming from
  the SWAN SOHO instrument, electron density values from LASCO-C2,
  and interplanetary solar wind velocities derived from ground-based
  interplanetary scintillation observations (IPS). In a first step, we
  combine the LASCO electron densities at 6 R<SUB>solar</SUB> and the IPS
  velocities and compare the product to the SWAN mass fluxes. It is found
  that this product represents the actual mass flux at 6 R<SUB>solar</SUB>
  for the fast wind, but not for the slow wind. In regions dominated
  by the slow wind, the fluxes derived from SWAN are systematically
  smaller. This is interpreted as proof that the fast solar wind has
  reached its terminal velocity at ~6 R<SUB>solar</SUB> and expands with
  constant velocity beyond this distance. On the contrary, the slow solar
  wind has reached only half of its terminal value and is thus accelerated
  farther out. In a second step, we combine the LASCO-C2 density profiles
  and the SWAN flux data to derive velocity profiles in the corona between
  2.5 and 6 R<SUB>solar</SUB>. Such profiles can be used to test models
  of the acceleration mechanism of the fast solar wind.

---------------------------------------------------------
Title: Recent Evolution of the Kracht Group of Comets
Authors: Knight, Matthew M.; A'Hearn, M. F.; Biesecker, D. A.; Faury,
   G.; Hamilton, D. P.; Lamy, P.; Llebaria, A.
2007DPS....39.5903K    Altcode: 2007BAAS...39..534K
  The Kracht group contains 29 comets discovered in SOHO images from
  1996-2005 with perihelion distances of 7-11 solar radii and inclinations
  of 12-15 degrees. Unlike the much more populous Kreutz sungrazing group,
  many Kracht comets are observed to survive perihelion, and as many as
  five may have been observed on two apparitions, with periods ranging
  from 4.8-5.8 years. Kracht comets tend to arrive in clusters followed by
  many months devoid of comets before another cluster arrives. Ohtsuka
  et al. (2003) and Sekanina and Chodas (2005) have shown that the
  Kracht group represents an evolutionary stage of the Machholz complex,
  which has evolved over many centuries and also includes 96P/Machholz,
  the Marsden group of comets, and the Arietids. <P />Here we explain
  the recent evolution of individual members of the Kracht group as a
  series of cascading fragmentations of a few large comets (causing
  the temporal clusters) which have had somewhat different orbital
  histories since splitting from each other within the last hundred
  years or so (causing the gaps between temporal clusters). We use
  dynamical simulations to search for possible fragmentation scenarios
  and to estimate the rate at which the orbital elements evolve due to
  the gravitational influence of the planets. We predict that 8 of the
  19 fragments seen since 2002 may be observable in upcoming perihelion
  passages, including five that should reappear before the end of 2008. If
  observed, two of these will have been seen at three perihelion passages,
  allowing a rough estimation of the mass loss due to erosion. <P />This
  research was supported by NASA Planetary Atmospheres grant NNG06GF29G.

---------------------------------------------------------
Title: SEPPCoN: Comet Dust and Activity at Moderate Heliocentric
    Distances as Observed with Spitzer
Authors: Kelley, Michael S.; Fernández, Y. R.; Reach, W. T.; Lisse,
   C. M.; A'Hearn, M. F.; Bauer, J. M.; Campins, H.; Fitzsimmons, A.;
   Groussin, O.; Lamy, P. L.; Licandro, J.; Lowry, S. C.; Meech, K. J.;
   Pittichova, J.; Toth, I.; Weaver, H. A.
2007DPS....39.5407K    Altcode: 2007BAAS...39..525K
  A Survey of Ensemble Physical Properties of Cometary Nuclei (SEPPCoN)
  is underway to characterize the nuclei of 100 Jupiter-family comets
  (JFC). The survey combines both visible and mid-infrared observations
  to measure the JFC size and albedo distributions. We inspected Spitzer
  Space Telescope MIPS and IRS images of the survey targets for dust
  comae, tails, and trails. Out of 98 observed comets, we found 32 to
  have some emission from dust outside of the central point source. A
  few of these sources were also observed to have dust in visible,
  ground-based data. The heliocentric distances (rh) of the 32 targets
  range from 3.5 to 6.5 AU, with most between 4 and 5 AU. We derive
  color-temperatures for the 20 dust detections observed in both the 16
  and 22 micron IRS cameras and find the color-temperature approximately
  varies as 280*rh^(-0.5) [K], as expected for isothermal low-albedo
  dust in local thermodynamic equilibrium. We discuss the evidence for
  outliers from this trend. We compare our observations to dust syndynes
  and 3-dimensional dust models to distinguish dust trails from dust
  tails. Unlike dust tails, dust trails only weakly respond to solar
  radiation pressure and, therefore, likely represent the largest (&gt;
  1 mm) grains ejected from the nucleus. We also compare observations
  to model images in order to determine the extent of recent coma
  activity. Water sublimation is expected to be greatly extinguished on
  comet surfaces by 3.5 AU. Dust structures observed outside of this
  rh could arise from recent coma activity (timescales up to weeks)
  caused by the sublimation of highly volatile ices (such as CO2) or the
  crystallization of amorphous water ice. Alternatively, the observed
  dust may be slowly dispersing grains ejected at a much earlier epoch
  (timescales up to years) when water sublimation dominated coma activity.

---------------------------------------------------------
Title: Three-dimensional reconstruction of the streamer belt and
    other large-scale structures of the solar corona. I. Method
Authors: Saez, F.; Llebaria, A.; Lamy, P.; Vibert, D.
2007A&A...473..265S    Altcode:
  Context: The high spatial resolution, white-light images obtained by
  the LASCO coronagraphs provide a detailed record of the solar corona
  over almost a full solar cycle. Their analysis and interpretation poses
  a formidable challenge for ultimately retrieving the 3-dimensional
  distribution of electrons in the corona. <BR />Aims: Our goal is to
  implement an efficient forward modeling method capable of generating
  high-resolution synthetic images of large-scale coronal structures
  (the streamer belt, isolated streamers, coronal mass ejections) over
  any time scales (as long as a solar cycle) to be directly compared,
  both qualitatively and quantitatively, to coronographic images of the
  corona. <BR />Methods: Our model assumes a 3-dimensional distribution
  of electrons described by analytic functions and represented using
  the octree compression's techniques. The radiance of the synthetic
  images is calculated with a ray-tracing algorithm that incorporates
  the Thomson scattering. A multi-octree generalization of the method
  allows simulation of the temporal evolution of the structures. We first
  concentrate on the coronal streamer belt. Starting from photospheric
  magnetograms, we calculate the position of the neutral line at the
  source surface (2.5 R_sun) using the potential field source surface
  model. The plasma sheet forming the belt is centered on the current
  sheet represented as the radial extension of the neutral line. Its
  electron density is represented by a parametric function of both the
  distances to the Sun center and to the current sheet. The parameters
  are optimized by adjusting the synthetic images to the observations,
  using either the coronal images or synoptic maps of the corona. The
  method is then extended to other large-scale coronal structures,
  polar plumes, and coronal mass ejections. <BR />Results: As examples,
  we present results for the streamer belt observed by LASCO-C2 during two
  Carrington rotations, CR 1910 and CR 1913, as well as illustrations of
  future coronographic observations expected from the STEREO and Solar
  Orbiter missions. The results suggest that our method is sufficient
  for qualitatively and quantitatively simulating the structures of the
  solar corona even if some discrepancies can be noticed. A systematic
  analysis of the LASCO data over almost a full solar cycle will be
  developed in forthcoming articles.

---------------------------------------------------------
Title: Thermal Properties, Size Distribution, and Albedo Distribution
    of Jupiter-Family Comets
Authors: Fernandez, Yanga R.; Kelley, M. S.; Lamy, P. L.; Toth, I.;
   Groussin, O.; Lisse, C. M.; A'Hearn, M. F.; Bauer, J. M.; Campins, H.;
   Fitzsimmons, A.; Licandro, J.; Lowry, S. C.; Meech, K. J.; Pittichova,
   J.; Reach, W. T.; Weaver, H. A.
2007DPS....39.4301F    Altcode: 2007BAAS...39..497F
  We present results from SEPPCoN (Survey of Ensemble Physical Properties
  of Cometary Nuclei), a survey of 100 Jupiter-family comets (JFCs) using
  the Spitzer Space Telescope for mid-infrared measurements of thermal
  emission and several ground-based telescopes for visible-wavelength
  measurements of reflected sunlight. Our sample represents about 30%
  of all known JFCs. The Spitzer observations are complete, and each
  comet was observed at either two wavelengths (16 and 22 μm) or at
  one wavelength twice (24 μm). Our survey constrains the effective
  radii of the JFC nuclei and thence the size distribution while only
  assuming that cometary geometric albedos are low (few percent); we need
  not assume that they are all the same. Also, nearly all survey targets
  were observed when farther than 4 AU from the Sun to minimize (and in
  most cases eliminate) coma confusion. Using the observations of comets
  at two wavelengths, and using the Near-Earth Asteroid Thermal Model, we
  have estimated the JFC ensemble-average beaming parameter to be about
  1.1. On average, cometary nuclei seem to have low thermal inertia and
  not have significant infrared beaming, although we do find that some of
  our survey targets have significantly higher parameters and thus likely
  higher thermal inertia. Analysis on the cumulative size distribution
  continues and we present our preliminary estimate of its shape, as well
  as the implications for the assumption of uniform albedo and for the
  extent of the small-comet (sub-km) population. So far we have obtained
  visible magnitudes on almost half of our targets; we plan to complete
  this part of the survey in the coming years. With these data we will
  constrain the JFC albedo distribution and again address the question
  of albedo uniformity; current progress on this task is reported as
  well. We thank the Spitzer Science Center for supporting this research.

---------------------------------------------------------
Title: Active Regions On The Nucleus Of Comet
    67P/Churyumov-Gerasimenko
Authors: Groussin, Olivier; Lamy, P.; Jorda, L.; Besse, S.
2007DPS....39.3601G    Altcode: 2007BAAS...39..485G
  Rosetta will orbit and land on comet 67P/Churyumov-Gerasimenko in
  2014. The planning of the mission depends strongly on the location and
  intensity of active regions. We have developped a model to calculate the
  water production rate of 67P as a function of heliocentric distance. Our
  model takes into account the orbital elements of 67P, the orientation of
  the pole, the rotational period, the shape (spherical or more complex)
  and the localisation and type of active regions (either small, very
  active regions or extended, low active regions). The comparison between
  the water production rates calculated by the model and the compilation
  of water production rates from the 1982 and 1996 perihelion passages by
  D.G. Schleicher (2006, Icarus 181, 442-457) gives some constraints on
  the localisation of active regions. A particular emphasis is placed
  on reproducing the rotational variability of the water production
  rate. <P />We derive that one small very active region covering about
  4-5% of the nucleus surface and located in the Northern hemisphere at
  a latitude of about +65 degree is sufficient to match the data and
  their temporal variations. Two small active regions located in the
  Northern hemisphere is not excluded but less probable. One extended,
  low active region covering about 60% of the nucleus surface can also
  fit the data, but only the part in the Northern hemisphere contributes
  to the production rate at perihelion. The case with one region only,
  located in the Southern hemisphere, is excluded, so that there must be
  active regions in the Northern hemisphere of 67P. Finally, we conclude
  that the shape (spherical or more complex) has no influence on the
  localisation of the active regions. <P />This work was supported by
  a grant from the CNES.

---------------------------------------------------------
Title: The giant externally occulted coronagraph ASPIICS for the
    PROBA-3 formation flying mission
Authors: Vivès, Sébastien; Lamy, Philippe; Venet, Melanie; Levacher,
   Patrick; Boit, J. L.
2007SPIE.6689E..0FV    Altcode: 2007SPIE.6689E..11V
  Formation flying opens new perspectives in solar physics, and
  allow to conceive giant, externally-occulted coronagraphs using
  a two-component space system with the external occulter on one
  spacecraft and the optical instrument on the other spacecraft at a
  distance of hundred meters. ASPIICS (Association de Satellites Pour
  l'Imagerie et l'Interferometrie de la Couronne Solaire) is a mission
  proposed to ESA in the framework of its PROBA-3 demonstration program
  of formation flying which is presently in phase A. ASPIICS is a single
  coronagraph which will perform both high spatial resolution imaging
  of the solar corona as well as 2-dimensional spectroscopy of several
  emission lines from the coronal base out to 3 R(symbol) using an etalon
  Fabry-Perot interferometer. The selected lines will allow to address
  different coronal regions: the forbidden line of FeXIV at 530.285 nm
  (hot coronal matter), Fe IX/X at 637.4 nm (coronal holes), HeI at
  587.6 nm (cold matter). An additional broad spectral channel will
  image the white light corona so as to derive electron densities. The
  classical design of an externally-occulted coronagraph is adapted to
  the formation flying configuration allowing the detection of the very
  inner corona as close as 0.01 R(symbol) from the solar limb.

---------------------------------------------------------
Title: The BepiColombo Laser Altimeter (BELA): Concept and baseline
    design
Authors: Thomas, N.; Spohn, T.; Barriot, J. -P.; Benz, W.; Beutler,
   G.; Christensen, U.; Dehant, V.; Fallnich, C.; Giardini, D.; Groussin,
   O.; Gunderson, K.; Hauber, E.; Hilchenbach, M.; Iess, L.; Lamy, P.;
   Lara, L. -M.; Lognonné, P.; Lopez-Moreno, J. J.; Michaelis, H.;
   Oberst, J.; Resendes, D.; Reynaud, J. -L.; Rodrigo, R.; Sasaki, S.;
   Seiferlin, K.; Wieczorek, M.; Whitby, J.
2007P&SS...55.1398T    Altcode:
  The BepiColombo Laser Altimeter (BELA) has been selected for flight on
  board the European Space Agency's BepiColombo Mercury Planetary Orbiter
  (MPO). The experiment is intended to be Europe's first planetary laser
  altimeter system. Although the proposed system has similarities to the
  Mercury Laser Altimeter (MLA) currently flying on board NASA's MESSENGER
  mission to Mercury, the specific orbit and construction of the MPO
  force the use of novel concepts for BELA. Furthermore, the base-lined
  range-finding approach is novel. In this paper, we describe the BELA
  system and show preliminary results from some prototype testing.

---------------------------------------------------------
Title: Old and New Aspects of Prominence Physics from Coronal
    Observations
Authors: Koutchmy, S.; Filippov, B.; Lamy, P.
2007ASPC..368..331K    Altcode:
  Classical W-L eclipse observations at typical spatial resolution
  of 10 arcsec show dark cavities surrounding prominences. Images at
  higher spatial resolution processed with a spatial filter reveal
  small dynamical cool clouds moving inside the inner corona around
  prominences. More recently EIT/SoHO observations taken using the
  304 Å channel showed He<SUP>+</SUP> prominences sometimes not seen
  in cooler lines. TRACE movies of the Fe IX and XI emissions where
  prominences are seen in absorption also bring appreciable informations
  on the dynamical surrounding of prominences, without showing obvious
  correlations between prominence and coronal structures. Accordingly,
  we re-examine the significance of the cavity and propose a possible
  interpretation as magnetic interlaced 3-D flux ropes and loops
  evacuating the corona, in addition to twisted flux ropes where the
  prominence plasma is condensing. Future space missions like ASPIICS
  should pay more attention to cavities and emptiness, to coronal dynamics
  around prominences, in order to resolve the long-standing problem of
  the origin of prominences and perhaps, perform a new diagnostic of
  the erupting process responsible for many CMEs.

---------------------------------------------------------
Title: Characterization of Asteroid 2867 Steins, a Target of the
    Rosetta Mission
Authors: Lamy, Philippe; Barucci, Antonella; Dotto, Elisabetta;
   Fornasier, Sonia; Fulchignoni, Marcello; Groussin, Olivier; Jorda,
   Laurent
2007sptz.prop40259L    Altcode:
  We propose to re-observe asteroids 2867 Steins, one of the target
  of the Rosetta mission in order to definitevely ascertain its
  taxonomic classification and its surface composition. Our previous SST
  observations performed during cycle 2 had to assume a much bigger size
  than presently established, and our spectra do not have a good enough
  signal-over-noise ratio to clearly distinguish the exact position of
  the different bands. The proposed SST observations consist in taking
  low resolution spectra with the IRS instrument over its full wavelength
  range 5-38 micron so as to reach a signal-over-noise ratio larger than
  200 in the 7-20 micron spectral range which is of prime interest for
  identification of the mineralogical features. Five individual spectra
  will be obtained for a total observing time of 1.4 hr. The expected
  results will allow identifying the mineralogical signatures so as to
  determine the taxonomic classification, the surface composition and
  possible weathering processes.

---------------------------------------------------------
Title: Chromospheric and Prominence Physics with the ASPIICS Formation
    Flying Coronagraph
Authors: Lamy, P.; Vivès, S.; Koutchmy, S.; Arnaud, J.
2007ASPC..368..639L    Altcode:
  Classical externally-occulted coronagraphs are presently limited in
  their performances by the distance between the external occulter and
  the front objective. The diffraction fringe from the occulter and
  the vignetted pupil which degrades the spatial resolution prevent
  observing the inner corona inside typically 2--2.5 solar radii
  (R<SUB>⊙</SUB>). Formation flying opens new perspectives and allow to
  conceive giant, externally-occulted coronagraphs using a two-component
  space system with the external occulter on one spacecraft and the
  optical instrument on the other spacecraft. ASPIICS (Association
  de Satellites Pour l'Imagerie et l'Interférométrie de la Couronne
  Solaire) is a mission proposed to ESA in the framework of the PROBA-3
  program of formation flying which is presently under study, to exploit
  this technique for coronal observations. ASPIICS is composed of a
  single coronagraph which performs high spatial resolution imaging of
  the corona as well as 2-dimensional spectroscopy of several emission
  lines (in particular the forbidden line of Fe XIV at 530.285 nm) from
  the coronal base out to 3 R<SUB>⊙</SUB>. The classical design of an
  externally occulted coronagraph is adapted to the detection of the very
  inner corona, and the addition of a Fabry-Pérot interferometer. By
  tuning the position of the occulter spacecraft, it will be possible to
  reach the chromosphere and the upper part of the spicules. Filtergrams
  on the helium D3 line or even better, the hydrogen Hβ line (which is
  optically thin contrary to Hα) will give access to the “cold corona”,
  and could allow measuring the chromospheric prolateness.

---------------------------------------------------------
Title: Measuring the physical properties of the nucleus of comet
    8P/Tuttle
Authors: Groussin, Olivier; Fernandez, Yanga; Jorda, Laurent; Kelley,
   Michael; Lamy, Philippe; Toth, Imre; Weaver, Hal
2007sptz.prop40270G    Altcode:
  Comet 8P/Tuttle is a returning nearly isotropic comet (NIC), i.e.,
  an 'Oort cloud comet', with an outstanding apparition in cycle 4,
  passing within 0.25 AU of the Earth. We propose to observe it with
  MIPS (photometry at 24 and 70 micron) and IRS (spectroscopy in the
  5-38 micron range), to measure the physical properties of its nucleus:
  size, shape, rotation period, thermal inertia and mineralogy. This will
  provide the most detailed view of a NIC nucleus since the spacecraft
  flyby of 1P/Halley in 1986. The return of 8P is a rare opportunity
  that Spitzer should not miss. The results should yield a comprehensive
  picture of this NIC that can be compared to the detailed data collected
  on ecliptic comets (ECs) during the past 3 decades. The differences
  and similarities between NICs and ECs should yield valuable insights
  into the origin and evolution of comets.

---------------------------------------------------------
Title: The long-term evolution and initial size of comets 46P/Wirtanen
    and 67P/Churyumov-Gerasimenko
Authors: Groussin, O.; Hahn, G.; Lamy, P. L.; Gonczi, R.; Valsecchi,
   G. B.
2007MNRAS.376.1399G    Altcode: 2007MNRAS.tmp..179G
  We present a new method to study the long-term evolution of
  cometary nuclei in order to estimate their original size, and
  we consider the case of comets 46P/Wirtanen (hereafter 46P) and
  67P/Churyumov-Gerasimenko (hereafter 67P). We calculate the past
  evolution of the orbital elements of both comets over 100000yr
  using a Bulirsch-Stoer integrator and over 450000yr using a Radau
  integrator, and we incorporate a realistic model of the erosion of
  their nucleus. Their long-term orbital evolution is prominently chaotic,
  resulting from several close encounters with planets, and this result
  is independent of the choice of the integrator and of the presence
  or not of non-gravitational forces. The dynamical lifetime of comet
  46P is estimated at ~133000yr and that of comet 67P at ~105000yr. Our
  erosion model assumes a spherical nucleus composed of a macroscopic
  mixture of two thermally decoupled components, dust and pure water
  ice. Erosion strongly depends upon the active fraction and the density
  of the nucleus. It mainly takes place at heliocentric distances &lt;4au
  and lasts for only ~7 per cent of the lifetime. Assuming a density
  of 300kgm<SUP>-3</SUP> and an average active fraction over time of 10
  per cent, we find an initial radius of ~1.3km for 46P and ~2.8km for
  67P. Upper limit are obtained assuming a density of 100kgm<SUP>-3</SUP>
  and an active fraction of 100 per cent, and amounts to 21km for
  46P and 25km for 67P. Erosion acts as a rejuvenating process of the
  surface so that exposed materials on the surface may only contain
  very little quantities of primordial materials. However, materials
  located just under it (a few centimetres to metres) may still be much
  less evolved. We will apply this method to several other comets in
  the future.

---------------------------------------------------------
Title: Rotational state of the nucleus of Comet 9P/Tempel 1: Results
    from Hubble Space Telescope observations in 2004
Authors: Lamy, Philippe L.; Toth, Imre; A'Hearn, Michael F.; Weaver,
   Harold A.; Jorda, Laurent
2007Icar..187..132L    Altcode:
  The nucleus of Comet 9P/Tempel 1 was first observed with the Hubble
  Space Telescope (HST) in December 1997 [Lamy, P., Toth, I., A'Hearn,
  M.F., Weaver, H., Weissman, P.R., 2001. Icarus 154, 337-344], but
  the temporal coverage was insufficient to determine its rotational
  period. Because the success of the Deep Impact mission was critically
  dependent on understanding the rotational state and approximate shape
  and size of the nucleus, we extensively re-observed 9P/Tempel 1,
  this time with the Advanced Camera for Surveys (HST/ACS), from May
  7.9 to 9.5, 2004 (UT). At the mid-point of the observing window, the
  comet was 3.52 AU from the Sun, 4.03 AU from the Earth, and at a solar
  phase angle of 13.3°. The program was comprised of 18 separate visits,
  each one corresponding to an HST orbit filled with 3 ACS exposures of
  either 800 or 857 s duration with the F606W broadband filter. These
  very deep exposures revealed a star-like object, without any apparent
  coma. The light curve, defined by 49 data points, is characterized
  by a mean apparent V magnitude of 21.8 and an amplitude of 0.5 mag,
  indicating that we were viewing the varying cross-section of a rotating,
  elongated body. The periodicity was analyzed with seven different
  techniques yielding a rotational period in the range 39.40 to 43.00 h,
  and a mean value of 41.27±1.85 h (1 σ). Using an albedo p=0.04 and a
  linear phase law with a coefficient β=0.0465 magdeg, we determined an
  effective radius of 3.01 km; a possible prolate spheroid solution has
  semi-axes a=3.71 km, b=2.36 km and a minimum axial ratio a/b∼1.57. By
  comparing the light curves obtained in 1997 and in 2004, we were able
  to constrain the phase function of the nucleus. Finally, an upper
  limit of Afρ&lt;0.04 cm is set based on the non-detection of the coma.

---------------------------------------------------------
Title: Observations of Comet 9P/Tempel 1 around the Deep Impact
    event by the OSIRIS cameras onboard Rosetta
Authors: Keller, Horst Uwe; Küppers, Michael; Fornasier, Sonia;
   Gutiérrez, Pedro J.; Hviid, Stubbe F.; Jorda, Laurent; Knollenberg,
   Jörg; Lowry, Stephen C.; Rengel, Miriam; Bertini, Ivano; Cremonese,
   Gabriele; Ip, Wing-H.; Koschny, Detlef; Kramm, Rainer; Kührt,
   Ekkehard; Lara, Luisa-Maria; Sierks, Holger; Thomas, Nicolas; Barbieri,
   Cesare; Lamy, Philippe; Rickman, Hans; Rodrigo, Rafael; A'Hearn,
   Michael F.; Angrilli, Francesco; Barucci, Maria-Antonella; Bertaux,
   Jean-Loup; da Deppo, Vania; Davidsson, Björn J. R.; de Cecco,
   Mariolino; Debei, Stefano; Fulle, Marco; Gliem, Fritz; Groussin,
   Olivier; Lopez Moreno, José J.; Marzari, Francesco; Naletto,
   Giampiero; Sabau, Lola; Sanz Andrés, Angel; Wenzel, Klaus-Peter
2007Icar..187...87K    Altcode:
  The OSIRIS cameras on the Rosetta spacecraft observed Comet 9P/Tempel
  1 from 5 days before to 10 days after it was hit by the Deep Impact
  projectile. The Narrow Angle Camera (NAC) monitored the cometary dust
  in 5 different filters. The Wide Angle Camera (WAC) observed through
  filters sensitive to emissions from OH, CN, Na, and OI together with
  the associated continuum. Before and after the impact the comet showed
  regular variations in intensity. The period of the brightness changes
  is consistent with the rotation period of Tempel 1. The overall
  brightness of Tempel 1 decreased by about 10% during the OSIRIS
  observations. The analysis of the impact ejecta shows that no new
  permanent coma structures were created by the impact. Most of the
  material moved with ∼200ms. Much of it left the comet in the form
  of icy grains which sublimated and fragmented within the first hour
  after the impact. The light curve of the comet after the impact and
  the amount of material leaving the comet ( 4.5-9×10kg of water ice
  and a presumably larger amount of dust) suggest that the impact ejecta
  were quickly accelerated by collisions with gas molecules. Therefore,
  the motion of the bulk of the ejecta cannot be described by ballistic
  trajectories, and the validity of determinations of the density and
  tensile strength of the nucleus of Tempel 1 with models using ballistic
  ejection of particles is uncertain.

---------------------------------------------------------
Title: Properties of the dust cloud caused by the Deep Impact
    experiment
Authors: Jorda, L.; Lamy, P.; Faury, G.; Keller, H. U.; Hviid, S.;
   Küppers, M.; Koschny, D.; Lecacheux, J.; Gutiérrez, P.; Lara, L. M.
2007Icar..187..208J    Altcode:
  We present an analysis of the observations of the Deep Impact event
  performed by the OSIRIS narrow angle camera aboard the Rosetta
  spacecraft over two weeks, in an effort to characterize the cometary
  dust grains ejected from the nucleus of Comet 9P/Tempel 1. We adopt
  a Monte Carlo approach to generate calibrated synthetic images, and
  a linear combination of them is fitted to the calibrated images so
  as to determine the physical parameters of the dust cloud. Our model
  considers spherical olivine particles with a density of 3780 kg m
  <SUP>-3</SUP>. It incorporates constraints on the direction of the
  cone of emission coming from additional images obtained at Pic du Midi
  observatory, and constraints on the dust terminal velocities coming from
  the physics of the impact. We find that the slope of the differential
  dust size distribution of grains with radii &lt;20 μm ( β&gt;0.008)
  is 3.1±0.3, a value typical of cometary dust tails. This shows that
  there is no evidence in our data for an enhancement in sub-micron
  particles in the ejecta compared to the typical dust distribution of
  active comets. We estimate the mass of particles with radii &lt;1.4 μm
  ( β&gt;0.14) to be 1.5±0.2×10 kg. These particles represent more
  than 80% of the cross-section of the observed dust cloud. The mass
  carried by larger particles depends whether the gas significantly
  increases the kinetic energy of the grains in the inner coma; it
  lies in the range 1-14×10 kg for particles with radii &lt;100 μm
  ( β&gt;0.002). We obtain the distribution of terminal velocities
  reached by the dust after the dust-gas interaction which is very well
  constrained between 10 and 600 m s <SUP>-1</SUP>. It is characterized
  by Gaussian with a maximum at about 190 m s <SUP>-1</SUP> and a width
  at half maximum of 150 m s <SUP>-1</SUP>.

---------------------------------------------------------
Title: Commission 21: Light of the Night Sky
Authors: Gustafson, Bo Å. S.; Witt, Adolf N.; Dwek, E.; Lamy, P.;
   Henry, R.; Mann, I.
2007IAUTA..26..161G    Altcode:
  Commission 21, one of IAU's smallest commissions, consists of some
  hundred members and consultants working to understand and describe the
  light of the night sky with emphasis on the diffuse components. Many
  more work on these topics without being members of the commission. Light
  is here defined in its broader sense of electromagnetic radiation of
  any frequency. The diffuse components of the light of the night sky
  encompass a variety of physical phenomena over the full range of cosmic
  distance scales and include scattered light, thermal emission, line
  emission, and any other emission phenomena producing a diffuse light
  source. These attract interest not only as scientific topics of study
  in their own right but also as an unwanted foreground or background
  against which all other sky phenomena are observed. Commission 21 has
  for mandate to promote research and availability of results on issues
  related to the diffuse light of the night sky. This document is a report
  on activities in this field and is not confined to the activities of its
  members, no distinction is made between work carried out by commission
  members and non commission members. The report is organized starting
  with a summary of the state of broad surveys that provide most of the
  observations. The report on developments in the various disciplines
  start with the sources closest to the observer known as airglow and
  progresses by way of the interplanetary and interstellar mediums to
  the increasingly distant integrated starlight, diffuse galactic light
  and diffuse emission in other galaxies ending with the extragalactic
  background radiation.

---------------------------------------------------------
Title: OSIRIS   The Scientific Camera System Onboard Rosetta
Authors: Keller, H. U.; Barbieri, C.; Lamy, P.; Rickman, H.; Rodrigo,
   R.; Wenzel, K. -P.; Sierks, H.; A'Hearn, M. F.; Angrilli, F.; Angulo,
   M.; Bailey, M. E.; Barthol, P.; Barucci, M. A.; Bertaux, J. -L.;
   Bianchini, G.; Boit, J. -L.; Brown, V.; Burns, J. A.; Büttner, I.;
   Castro, J. M.; Cremonese, G.; Curdt, W.; Deppo, V. Da; Debei, S.;
   Cecco, M. De; Dohlen, K.; Fornasier, S.; Fulle, M.; Germerott, D.;
   Gliem, F.; Guizzo, G. P.; Hviid, S. F.; Ip, W. -H.; Jorda, L.; Koschny,
   D.; Kramm, J. R.; Kührt, E.; Küppers, M.; Lara, L. M.; Llebaria,
   A.; López, A.; López-Jimenez, A.; López-Moreno, J.; Meller, R.;
   Michalik, H.; Michelena, M. D.; Müller, R.; Naletto, G.; Origné, A.;
   Parzianello, G.; Pertile, M.; Quintana, C.; Ragazzoni, R.; Ramous,
   P.; Reiche, K. -U.; Reina, M.; Rodríguez, J.; Rousset, G.; Sabau,
   L.; Sanz, A.; Sivan, J. -P.; Stöckner, K.; Tabero, J.; Telljohann,
   U.; Thomas, N.; Timon, V.; Tomasch, G.; Wittrock, T.; Zaccariotto, M.
2007SSRv..128..433K    Altcode: 2007SSRv..tmp...26K
  The Optical, Spectroscopic, and Infrared Remote Imaging System OSIRIS
  is the scientific camera system onboard the Rosetta spacecraft
  (Figure 1). The advanced high performance imaging system will be
  pivotal for the success of the Rosetta mission. OSIRIS will detect
  67P/Churyumov-Gerasimenko from a distance of more than 10<SUP>6</SUP>
  km, characterise the comet shape and volume, its rotational state and
  find a suitable landing spot for Philae, the Rosetta lander. OSIRIS
  will observe the nucleus, its activity and surroundings down to a
  scale of ~2 cm px<SUP>−1</SUP>. The observations will begin well
  before the onset of cometary activity and will extend over months
  until the comet reaches perihelion. During the rendezvous episode of
  the Rosetta mission, OSIRIS will provide key information about the
  nature of cometary nuclei and reveal the physics of cometary activity
  that leads to the gas and dust coma.

---------------------------------------------------------
Title: Civa
Authors: Bibring, J. -P.; Lamy, P.; Langevin, Y.; Soufflot, A.;
   Berthé, M.; Borg, J.; Poulet, F.; Mottola, S.
2007SSRv..128..397B    Altcode: 2007SSRv..tmp...81B
  CIVA (Comet Infrared and Visible Analyser) is an integrated set of
  imaging instruments, designed to characterize the 360<SUP>∘</SUP>
  panorama (CIVA-P) as seen from the Rosetta Lander Philae, and to study
  surface and subsurface samples (CIVA-M). CIVA-P is a panoramic stereo
  camera, while CIVA-M is an optical microscope coupled to a near infrared
  microscopic hyperspectral imager. CIVA shares a common Imaging Main
  Electronics (IME) with ROLIS. CIVA-P will characterize the landing site,
  with an angular sampling (IFOV) of 1.1 mrad: each pixel will image
  a 1 mm size feature at the distance of the landing legs, and a few
  metres at the local horizon. The panorama will be mapped by 6 identical
  miniaturized micro-cameras covering contiguous FOV, with their optical
  axis 60<SUP>∘</SUP> apart. Stereoscopic capability will be provided
  by an additional micro-camera, identical to and co-aligned with one
  of the panoramic micro-camera, with its optical axis displaced by 10
  cm. CIVA-M combines two ultra-compact and miniaturised microscopes,
  one operating in the visible and one constituting an IR hyperspectral
  imaging spectrometer: they will characterize, by non-destructive
  analyses, the texture, the albedo, the molecular and the mineralogical
  composition of each of the samples provided by the Sample Drill and
  Distribution (SD2) system. For the optical microscope, the spatial
  sampling is 7 μm; for the IR, the spectral range (1-4 μm) and the
  spectral sampling (5 nm) have been chosen to allow identification of
  most minerals, ices and organics, on each pixel, 40 μm in size. After
  being studied by CIVA, the sample could be analysed by a subsequent
  experiment (PTOLEMY and/or COSAC). The process would be repeated for
  each sample obtained at different depths and/or locations.

---------------------------------------------------------
Title: A Portrait of the Nucleus of Comet 67P/Churyumov-Gerasimenko
Authors: Lamy, Philippe L.; Toth, Imre; Davidsson, Björn J. R.;
   Groussin, Olivier; Gutiérrez, Pedro; Jorda, Laurent; Kaasalainen,
   Mikko; Lowry, Stephen C.
2007SSRv..128...23L    Altcode: 2007SSRv..tmp...74L
  In 2003, comet 67P/Churyumov-Gerasimenko was selected as the new target
  of the Rosetta mission as the most suitable alternative to the original
  target, comet 46P/Wirtanen, on the basis of orbital considerations
  even though very little was known about the physical properties of
  its nucleus. In a matter of a few years and based on highly focused
  observational campaigns as well as thorough theoretical investigations,
  a detailed portrait of this nucleus has been established that will serve
  as a baseline for planning the Rosetta operations and observations. In
  this review article, we present a novel method to determine the size
  and shape of a cometary nucleus: several visible light curves were
  inverted to produce a size-scale free three-dimensional shape, the
  size scaling being imposed by a thermal light curve. The procedure
  converges to two solutions which are only marginally different. The
  nucleus of comet 67P/Churyumov-Gerasimenko emerges as an irregular
  body with an effective radius (that of the sphere having the same
  volume) = 1.72 km and moderate axial ratios a/b = 1.26 and a/c =
  1.5 to 1.6. The overall dimensions measured along the principal axis
  for the two solutions are 4.49-4.75 km, 3.54-3.77 km and 2.94-2.92
  km. The nucleus is found to be in principal axis rotation with a
  period = 12.4-12.7 h. Merging all observational constraints allow us
  to specify two regions for the direction of the rotational axis of
  the nucleus: RA = 220°<SUP>+50°</SUP><SUB>−30°</SUB> and Dec =
  −70<SUP>°</SUP> ± 10<SUP>°</SUP> (retrograde rotation) or RA =
  40°<SUP>+50°</SUP><SUB>-30°</SUB> and Dec = +70<SUP>°</SUP>±
  10<SUP>°</SUP> (prograde), the better convergence of the various
  determinations presently favoring the first solution. The phase
  function, although constrained by only two data points, exhibits a
  strong opposition effect rather similar to that of comet 9P/Tempel
  1. The definition of the disk-integrated albedo of an irregular body
  having a strong opposition effect raises problems, and the various
  alternatives led to a R-band geometric albedo in the range 0.045-0.060,
  consistent with our present knowledge of cometary nuclei. The active
  fraction is low, not exceeding ~ 7% at perihelion, and is probably
  limited to one or two active regions subjected to a strong seasonal
  effect, a picture coherent with the asymmetric behaviour of the
  coma. Our slightly downward revision of the size of the nucleus of
  comet 67P/Churyumov-Gerasimenko resulting from the present analysis
  (with the correlative increase of the albedo compared to the originally
  assumed value of 0.04), and our best estimate of the bulk density of
  370 kg m<SUP>−3</SUP>, lead to a mass of ~ 8 × 10<SUP>12</SUP>
  kg which should ease the landing of Philae and insure the overall
  success of the Rosetta mission.

---------------------------------------------------------
Title: Properties of the dust cloud caused by the Deep Impact
    experiment
Authors: Jorda, L.; Lamy, P.; Faury, G.; Keller, H. U.; Hviid, S.;
   Küppers, M.; Koschny, D.; Lecacheux, J.; Gutiérrez, P.; Lara, L. M.
2007Icar..191S.412J    Altcode: 2007Icar..191..412J
  We present an analysis of the observations of the Deep Impact event
  performed by the OSIRIS narrow angle camera aboard the Rosetta
  spacecraft over two weeks, in an effort to characterize the cometary
  dust grains ejected from the nucleus of Comet 9P/Tempel 1. We adopt
  a Monte Carlo approach to generate calibrated synthetic images,
  and a linear combination of them is fitted to the calibrated images
  so as to determine the physical parameters of the dust cloud. Our
  model considers spherical olivine particles with a density of 3780
  kg m<SUP>-3</SUP>. It incorporates constraints on the direction of the
  cone of emission coming from additional images obtained at Pic du Midi
  observatory, and constraints on the dust terminal velocities coming from
  the physics of the impact. We find that the slope of the differential
  dust size distribution of grains with radii &lt;20 μm (β&gt;0.008)
  is 3.1±0.3, a value typical of cometary dust tails. This shows that
  there is no evidence in our data for an enhancement in sub-micron
  particles in the ejecta compared to the typical dust distribution of
  active comets. We estimate the mass of particles with radii &lt;1.4
  μm (β&gt;0.14) to be 1.5±0.2×10<SUP></SUP> kg. These particles
  represent more than 80% of the cross-section of the observed dust
  cloud. The mass carried by larger particles depends whether the gas
  significantly increases the kinetic energy of the grains in the inner
  coma; it lies in the range 1 14×10<SUP></SUP> kg for particles with
  radii &lt;100 μm (β&gt;0.002). We obtain the distribution of terminal
  velocities reached by the dust after the dust gas interaction which
  is very well constrained between 10 and 600 m s<SUP>-1</SUP>. It is
  characterized by Gaussian with a maximum at about 190 m s<SUP>-1</SUP>
  and a width at half maximum of 150 m s<SUP>-1</SUP>.

---------------------------------------------------------
Title: Determination of the light curve of the Rosetta target asteroid
    (2867) Steins by the OSIRIS cameras onboard Rosetta
Authors: Küppers, M.; Mottola, S.; Lowry, S. C.; A'Hearn, M. F.;
   Barbieri, C.; Barucci, M. A.; Fornasier, S.; Groussin, O.; Gutiérrez,
   P.; Hviid, S. F.; Keller, H. U.; Lamy, P.
2007A&A...462L..13K    Altcode: 2006astro.ph.12097K
  Context: In 2004 asteroid (2867) Steins has been selected as a flyby
  target for the Rosetta mission. Determination of its spin period and
  the orientation of its rotation axis are essential for optimization
  of the flyby planning. <BR />Aims: Measurement of the rotation period
  and light curve of asteroid (2867) Steins at a phase angle larger than
  achievable from ground based observations, providing a high quality
  data set to contribute to the determination of the orientation of the
  spin axis and of the pole direction. <BR />Methods: On March 11, 2006,
  asteroid (2867) Steins was observed continuously for 24 h with the
  scientific camera system OSIRIS onboard Rosetta. The phase angle was
  41.7 degrees, larger than the maximum phase angle of 30 degrees when
  Steins is observed from Earth. A total of 238 images, covering four
  rotation periods without interruption, were acquired. <BR />Results:
  The light curve of (2867) Steins is double peaked with an amplitude of
  ≈0.23 mag. The rotation period is 6.052~± 0.007 h. The continuous
  observations over four rotation periods exclude the possibility
  of period ambiguities. There is no indication of deviation from a
  principal axis rotation state. Assuming a slope parameter of G = 0.15,
  the absolute visual magnitude of Steins is 13.05 ± 0.03. <P />Table
  2 is only available in electronic form at http://www.aanda.org

---------------------------------------------------------
Title: Hubble Space Telescope observations of the nucleus of Comet
    9P/Tempel 1
Authors: Lamy, P. L.; Toth, I.; A'Hearn, M. F.; Weaver, H. A.;
   Weissman, P. R.
2007Icar..191S...4L    Altcode: 2007Icar..191....4L
  The nucleus of Comet 9P/Tempel 1, the target of the Deep Impact mission,
  was detected during Hubble Space Telescope observations taken with
  the wide-field planetary camera 2 (WFPC2) on 31 December 1997 when
  the comet's solar phase angle was 3.°8, its heliocentric distance was
  4.48 AU, and its geocentric distance was 3.53 AU. Sixteen images were
  taken through the F675W filter, and all of them revealed a point-like
  source without any detectable coma. From these images, we derived the
  R magnitude of the nucleus in the Johnson Kron Cousins photometric
  system for the entire 11.5-h time span of the observations. Assuming
  a prolate spheroid whose spin axis lies close to the plane of the
  sky, the partial lightcurve indicates semi-axes a-3.9 km and b-2.8
  km (assuming a geometric albedo of 0.04 for the R band and a phase
  coefficient of 0.04 mag deg<SUP>-1</SUP>) and a rotational period
  in the range of ∼25-33 h. The upper limit of the parameter Afρ,
  which characterizes the dust production rate, is 1 cm. We also derive
  a fractional active area at 1.78 AU of ∼4%.

---------------------------------------------------------
Title: Observations of Comet 9P/Tempel 1 around the Deep Impact
    event by the OSIRIS cameras onboard Rosetta
Authors: Keller, Horst Uwe; Küppers, Michael; Fornasier, Sonia;
   Gutiérrez, Pedro J.; Hviid, Stubbe F.; Jorda, Laurent; Knollenberg,
   Jörg; Lowry, Stephen C.; Rengel, Miriam; Bertini, Ivano; Cremonese,
   Gabriele; Ip, Wing-H.; Koschny, Detlef; Kramm, Rainer; Kührt,
   Ekkehard; Lara, Luisa-Maria; Sierks, Holger; Thomas, Nicolas; Barbieri,
   Cesare; Lamy, Philippe; Rickman, Hans; Rodrigo, Rafael; A'Hearn,
   Michael F.; Angrilli, Francesco; Barucci, Maria-Antonella; Bertaux,
   Jean-Loup; da Deppo, Vania; Davidsson, Björn J. R.; de Cecco,
   Mariolino; Debei, Stefano; Fulle, Marco; Gliem, Fritz; Groussin,
   Olivier; Lopez Moreno, José J.; Marzari, Francesco; Naletto,
   Giampiero; Sabau, Lola; Sanz Andrés, Angel; Wenzel, Klaus-Peter
2007Icar..191S.241K    Altcode: 2007Icar..191..241K
  The OSIRIS cameras on the Rosetta spacecraft observed Comet 9P/Tempel
  1 from 5 days before to 10 days after it was hit by the Deep Impact
  projectile. The Narrow Angle Camera (NAC) monitored the cometary dust
  in 5 different filters. The Wide Angle Camera (WAC) observed through
  filters sensitive to emissions from OH, CN, Na, and OI together with
  the associated continuum. Before and after the impact the comet showed
  regular variations in intensity. The period of the brightness changes is
  consistent with the rotation period of Tempel 1. The overall brightness
  of Tempel 1 decreased by about 10% during the OSIRIS observations. The
  analysis of the impact ejecta shows that no new permanent coma
  structures were created by the impact. Most of the material moved
  with ∼200ms<SUP></SUP>. Much of it left the comet in the form of icy
  grains which sublimated and fragmented within the first hour after the
  impact. The light curve of the comet after the impact and the amount
  of material leaving the comet (4.5 9×10<SUP></SUP>kg of water ice
  and a presumably larger amount of dust) suggest that the impact ejecta
  were quickly accelerated by collisions with gas molecules. Therefore,
  the motion of the bulk of the ejecta cannot be described by ballistic
  trajectories, and the validity of determinations of the density and
  tensile strength of the nucleus of Tempel 1 with models using ballistic
  ejection of particles is uncertain.

---------------------------------------------------------
Title: Rotational state of the nucleus of Comet 9P/Tempel 1: Results
    from Hubble Space Telescope observations in 2004
Authors: Lamy, Philippe L.; Toth, Imre; A'Hearn, Michael F.; Weaver,
   Harold A.; Jorda, Laurent
2007Icar..191S.310L    Altcode: 2007Icar..191..310L
  The nucleus of Comet 9P/Tempel 1 was first observed with the Hubble
  Space Telescope (HST) in December 1997 [Lamy, P., Toth, I., A'Hearn,
  M.F., Weaver, H., Weissman, P.R., 2001. Icarus 154, 337 344], but
  the temporal coverage was insufficient to determine its rotational
  period. Because the success of the Deep Impact mission was critically
  dependent on understanding the rotational state and approximate shape
  and size of the nucleus, we extensively re-observed 9P/Tempel 1, this
  time with the Advanced Camera for Surveys (HST/ACS), from May 7.9 to
  9.5, 2004 (UT). At the mid-point of the observing window, the comet
  was 3.52 AU from the Sun, 4.03 AU from the Earth, and at a solar phase
  angle of 13.3°. The program was comprised of 18 separate visits, each
  one corresponding to an HST orbit filled with 3 ACS exposures of either
  800 or 857 s duration with the F606W broadband filter. These very deep
  exposures revealed a star-like object, without any apparent coma. The
  light curve, defined by 49 data points, is characterized by a mean
  apparent V magnitude of 21.8 and an amplitude of 0.5 mag, indicating
  that we were viewing the varying cross-section of a rotating, elongated
  body. The periodicity was analyzed with seven different techniques
  yielding a rotational period in the range 39.40 to 43.00 h, and a mean
  value of 41.27±1.85 h (1σ). Using an albedo p<SUB></SUB>=0.04 and
  a linear phase law with a coefficient β=0.0465 magdeg<SUP></SUP>, we
  determined an effective radius of 3.01 km; a possible prolate spheroid
  solution has semi-axes a=3.71 km, b=2.36 km and a minimum axial ratio
  a/b∼1.57. By comparing the light curves obtained in 1997 and in 2004,
  we were able to constrain the phase function of the nucleus. Finally,
  an upper limit of Afρ&lt;0.04 cm is set based on the non-detection
  of the coma.

---------------------------------------------------------
Title: Hubble Space Telescope observations of the nucleus and inner
    coma of comet 67P/Churyumov-Gerasimenko
Authors: Lamy, P. L.; Toth, I.; Weaver, H. A.; Jorda, L.; Kaasalainen,
   M.; Gutiérrez, P. J.
2006A&A...458..669L    Altcode:
  Context: .Following the postponement of the launch of the Rosetta
  spacecraft scheduled in January 2003, comet 67P/Churyumov-Gerasimenko
  emerged as the most suitable new target. However a critical issue was
  the size, that is, the mass of its nucleus, as the surface module
  Philae was designed to land on a nucleus with a radius no larger
  than approximately 1.5 km. <BR /> Aims: . It was therefore crucial
  to the success of the mission to achieve a timely characterization of
  the nucleus of 67P/C-G so as to take any proper action on the design
  needed before the new launch. <BR /> Methods: . We used the Wide Field
  Planetary Camera 2 (WFPC2) of the Hubble Space Telescope (HST) whose
  superior spatial resolution enabled us to accurately separate the
  signal of the nucleus from that of the coma. The observations were
  performed on 12 and 13 March 2003, when the comet was 2.50 AU from
  the Sun, 1.52 AU from the Earth, and at a phase angle of 4.8°. <BR
  /> Results: . The nucleus of comet 67P/Churyumov-Gerasimenko was
  easily detected, and we measured its V and R magnitudes in the
  Johnson-Kron-Cousins photometric system. Assuming that the nucleus is
  spherical, with a geometric albedo of 0.04 and a phase coefficient of
  0.04 mag/deg for the R band, we derived a radius of 1.98±0.02 km. The
  spheroidal solution has semiaxes a = 2.41 km and b = c = 1.55 km and
  a rotational period of 12.41±0.41 h. We inverted the light curve
  and solved it for a full three-dimensional nucleus having an overall
  size of 4.56×3.81×3.44 km viewed at an aspect angle of ∼80°
  (i.e., near equatorial view) at the time of our observations. When
  combined with other constraints, the direction of the pole is
  found at either RA = 40°<SUP>+70°</SUP><SUB>-20°</SUB> and Dec =
  +70±10° (prograde rotation) or RA = 250±30° and Dec = -70±10°
  (retrograde rotation). The color of the nucleus is moderately red
  with (V-R)=0.52±0.05. From an analysis of the dust coma, we derived
  Afρ = 40.2±0.3 cm, a dust production rate Q<SUB>d</SUB> ∼ 4 kg
  s<SUP>-1</SUP>, and we characterized its color. <BR />

---------------------------------------------------------
Title: Determination Of The Light Curve Of Rosetta Target Asteroid
    2867 Steins With The Osiris Narrow Angle Camera Onboard Rosetta
Authors: Kueppers, Michael; Keller, H. U.; Hviid, S. F.; Mottola,
   S.; Fornasier, S.; Barbieri, C.; Barucci, A.; Gutiérrez, P.; Lamy,
   P.; OSIRIS Team
2006DPS....38.5920K    Altcode: 2006BAAS...38..596K
  On its way to comet 67P/Churyumov-Gerasimenko, the European Space
  Agency's Rosetta spacecraft is going to fly by Asteroids 2867 Steins in
  Sept. 2008 and 21 Lutetia in July 2010. While 21 Lutetia is a large main
  belt asteroid with a long history of investigation, relatively little
  is known about 2867 Steins. In particular, knowledge of the rotation
  period and the orientation of the rotation axis are valuable for the
  flyby preparations. <P />OSIRIS is the scientific camera system onboard
  Rosetta, consisting of a narrow angle camera (NAC) and a wide angle
  camera (WAC). In March 2006, the NAC observed 2867 Steins continuously
  for 24 hours, acquiring 238 images, with a clear filter. The camera
  performed flawlessly. The data obtained from spacecraft are unique
  in terms of continuous temporal coverage and phase angle. Indeed,
  the NAC observations were taken at a phase angle of 42 deg., compared
  to a maximum phase angle of 30 deg. when seen from Earth. The distance
  between Rosetta and 2867 Steins was 1.06 AU. <P />The OSIRIS data show
  a double peaked light curve with an amplitude of 0.23 magnitudes and
  a synodic rotation period of 6.052 ± 0.035 hours, in good agreement
  with ground based data by Hicks et al. (2004, IAU Circular 8315) and
  Weissman et al. (2006, ACM Conference). The continuous observations
  over four rotations completely exclude the possibility of period
  ambiguities. There is no indication of deviation from a principal axis
  rotation state. The observations are being combined with Earth-based
  data sets to derive the orientation of the spin axis and pole position
  for 2867 Steins. <P />We acknowledge funding from the national space
  agencies ASI, CNES, DLR, the Spanish Space Program (Ministerio de
  Educación y Ciencia), SNSB, and ESA.

---------------------------------------------------------
Title: Visible and Infrared Observations of Asteroid 2867 Steins,
    a target of the Rosetta Mission
Authors: Lamy, Philippe L.; Jorda, L.; Fornasier, S.; Kaasalainen, M.;
   Lowry, S.; Barucci, A.; Faury, G.; Kuppers, M.; Toth, I.; Weissman, P.
2006DPS....38.5909L    Altcode: 2006BAAS...38..594L
  We present the results of a coordinated campaign of visible and infrared
  observations aimed at fostering our knowledge of asteroid 2867 Steins
  in preparation of its flyby by the Rosetta spacecraft in Sept. 2008,
  on its way to comet 67P/Churyumov-Gerasimenko. Our data set includes
  16 visible light curves and 14 infrared spectra. Fifteen light curves
  were obtained with various ground-based observatories and an additional
  one, with the narrow angle camera (NAC) of the OSIRIS scientific camera
  aboard Rosetta that continuously monitored 2867 Steins over 24 hr in
  March 2006. Simultaneous inversion of the 16 light curves allows to
  generate a three-dimensional shape model of 2867 Steins with axial
  ratios a/b = 1.2 and b/c = 1.6, to determine its rotational period
  (6.0481 ± 0.0004 hr) and two possible solutions for the direction
  of its rotational axis. The infrared spectra were obtained with the
  low resolution mode of the Spitzer space telescope IRS; they extend
  from 5 to 35 microns and sample the rotational light curve with a
  temporal resolution of 30 min. Preliminary analysis using a standard
  thermal model yield an equivalent diameter of approximately 5 km and
  an albedo in the range 0.30 - 0.40. This classifies 2867 Steins as an
  E-type asteroid, a class of differentiated bodies which experienced
  significant heating episodes. The large beaming factor probably implies
  a thermal inertia in the range 150 - 300 SI but this will be further
  explored using more elaborated thermal models.

---------------------------------------------------------
Title: HST Observations of the Nucleus Fragment
    73P/Schwassmann-Wachmann 3-C During its Close Approach to Earth
    in 2006
Authors: Toth, I.; Lamy, P.; Weaver, H.; A'Hearn, M.; Kaasalainen,
   M.; Lowry, S.
2006DPS....38.0601T    Altcode: 2006BAAS...38..489T
  Fragment C of 73P/Schwassmann-Wachmann 3 (73P) was first detected with
  the HST-WFPC2 on 26 November 2001 when its heliocentric and geocentric
  distances were 3.26 AU and 2.34 AU, respectively. At that time, we
  found a very active nucleus with an effective radius of 0.68±0.04
  km (Toth et al., 2005: Icarus 178, 235-247). The comet's favorable
  apparition in April-May 2006 offered an exceptional opportunity to
  re-observe this nucleus at close range. Our observations took place
  on 10 April when the comet was 1.24 AU from the Sun, 0.29 AU from the
  Earth, and at a phase angle of 31°. They were performed with the HRC
  mode of the ACS with three standard filters, F475W ("B"), F555W ("V")
  and F625W ("R"), as well as with the broadband F606W (broad "V") to
  search for possible orbiting fragments. Fragment C was highly active,
  and the nucleus and the coma contributed almost equally in the central
  pixels. Assuming a spherical body with a geometric albedo of 0.04 and
  a linear phase coefficient of 0.04 mag/deg for the R-band, we derived
  an effective radius of 0.41±0.02 km. The light curve suggest that
  we were seeing the varying cross-section of an elongated body and we
  determined a = 0.57±0.08 km, b = c = 0.31 ±0.02 km, the minimum
  axial ratio 1.8±0.3, and a rotational period of 3.7±0.2 hr. Its
  color is characterized by (V-R) = 0.57±0.11 and (B-V) = 1.16±0.20,
  slightly outside the main trend among cometary nuclei, but comparable
  to a few of them. We were unable to detect any fragment in the vicinity
  of the C fragment on our deep HST images. H.A.W. acknowledges support
  by NASA through grant GO-10625 from the STScI, S.C.L. acknowledges
  support from the UK Particle Physics and Astronomy Research Council,
  and I.T. acknowledges support from CNRS, France.

---------------------------------------------------------
Title: Hubble Space Telescope Investigation of the Disintegration
    of 73P/Schwassmann-Wachmann 3
Authors: Weaver, Harold A.; Lisse, C. M.; Mutchler, M. J.; Lamy, P.;
   Toth, I.; Reach, W. T.
2006DPS....38.0602W    Altcode: 2006BAAS...38..490W
  Following reports of dramatic temporal variability of the B and G
  fragments of 73P/Schwassmann-Wachmann 3 (73P/SW3) in early April 2006,
  our team was awarded Director's Discretionary time on the Hubble Space
  Telescope to investigate the continuing disintegration of the nuclei. We
  observed the B fragment three different times (UT 2006 April 18.974,
  19.773, and 20.773) and discovered a swarm of sub-fragments trailing
  behind the principal nucleus, including some that were probably released
  coincident with the brightness outbursts reported by ground-based
  observers during the first few days of April. The single observation
  of the G fragment (UT 2006 April 18.574) also showed a nearby swarm of
  sub-fragments, including some that were probably released just a few
  days prior to the Hubble observations. For both the B and G fragments,
  the Hubble images provide information on the fragmentation history of
  both nuclei during the preceding month, if not earlier. In contrast,
  a single Hubble observation of the C fragment during this same period
  (UT 2006 April 18.642) did not reveal any new sub-fragments, consistent
  with the rather steady activity observed for the C fragment throughout
  early-April by both ground-based facilities and another Hubble program
  (Lamy et al.). We examine in detail the morphology and kinematics of
  the continuing disintegration of the B and G fragments and compare the
  Hubble results to those obtained from earlier and later observations
  with the Spitzer Space Telescope to develop a more comprehensive
  understanding of the nucleus disruption process. <P />Financial
  support for this work was provided by NASA through grant GO-10992 from
  the STScI.

---------------------------------------------------------
Title: Aphelion Observations of the Nucleus of Comet
67P/Churyumov-Gerasimenko: Target of ESA's Rosetta Comet Orbiter
    Mission
Authors: Lowry, Stephen C.; Fitzsimmons, A.; Jorda, L.; Kaasalainen,
   M.; Lamy, P.; Toth, I.
2006DPS....38.0801L    Altcode: 2006BAAS...38..492L
  Rosetta is ESA's new comet orbiter mission, launched in
  March 2004 and currently en route to Jupiter-family comet
  67P/Churyumov-Gerasimenko. The probe will rendezvous with the comet
  in 2014 and remain in orbit around the nucleus for on-going detailed
  physical and compositional analysis. Pre-encounter observations of
  the target are important for characterization of the heliocentric
  light-curve behaviour and the physical properties of the nucleus,
  information that is critical for mission planning. We present our
  latest results from detailed observations carried out when the comet
  was near aphelion at a heliocentric distance of 5.6 AU. The comet was
  also at opposition, with an average phase angle of just 0.46°. Three
  nights of optical imaging data were taken with ESO's 3.5m NTT at
  La Silla (Chile), between May 10-14, 2005. The data includes CCD
  VRI-filter imaging taken with the EMMI instrument. The rotational
  signature of the nucleus was clearly detected at all passbands with
  no sign of resolved coma or dust trail. Full rotational light-curves
  in all three passbands were obtained, allowing detailed inspection of
  surface colours at all rotational phases. A Fourier analysis of the
  R-filter light-curve gives a robust best-fit synodic rotation period
  of 12.72 ± 0.05 hours. The observed brightness range of 0.38 ± 0.04
  magnitudes implies a projected nucleus axial ratio of 1.42 ± 0.05. The
  mean R-filter magnitude is 22.41 ± 0.03, which corresponds to mean
  nucleus effective radius of 2.26 ± 0.03 km (assuming an albedo and
  linear phase coefficient of 0.04). The projected semi-axial dimensions
  are therefore 2.94 ± 0.15 and 2.07 ± 0.04 km. Our size is slightly
  larger than a previous estimate [Lamy et al. 2003. BAAS 35, 970],
  which implies a steep phase-darkening law or a more complex phase
  function that includes an opposition-surge effect.

---------------------------------------------------------
Title: Understanding the Kreutz Sungrazing Comets
Authors: Knight, Matthew M.; A'Hearn, M. F.; Biesecker, D. A.; Faury,
   G.; Hamilton, D. P.; Lamy, P.; Llebaria, A.
2006DPS....38.2002K    Altcode: 2006BAAS...38..516K
  We present updated results of our photometric study of the Kreutz
  family comets observed by SOHO-LASCO. This is a continuation of earlier
  work by Biesecker et al. (2002) and includes all Kreutz comets which
  reached perihelion in the SOHO-LASCO field of view by the end of 2005,
  a sample of over 900 comets. Typical Kreutz light curves brighten
  at a relatively constant rate, reach a peak in brightness at 10-13
  solar radii (prior to perihelion), then fade rapidly, with a small
  subset displaying a second (smaller) peak in brightness inside of 6
  solar radii. We are attempting to explain these light curve features
  using physical models of the nucleus such as composition, density,
  porosity, and production rates and will report on our findings. We are
  also investigating the relationship between Kreutz comets and other
  comets observed by SOHO-LASCO (the sungrazing families: Meyer, Marsden,
  and Kracht, and other non-sungrazing comets) and with observations of
  prominent sungrazers seen from the ground, e.g. Ikeya-Seki (1965 f),
  to estimate production rates at larger heliocentric distances. From
  these rates we hope to improve the scaling relationship between size
  and apparent brightness and constrain the size distribution of the
  Kreutz family. <P />This research was supported by NASA Planetary
  Atmospheres grant NAG513295.

---------------------------------------------------------
Title: In situ dust measurements in the inner Saturnian system
Authors: Srama, R.; Kempf, S.; Moragas-Klostermeyer, G.; Helfert, S.;
   Ahrens, T. J.; Altobelli, N.; Auer, S.; Beckmann, U.; Bradley, J. G.;
   Burton, M.; Dikarev, V. V.; Economou, T.; Fechtig, H.; Green, S. F.;
   Grande, M.; Havnes, O.; Hillier, J. K.; Horanyi, M.; Igenbergs, E.;
   Jessberger, E. K.; Johnson, T. V.; Krüger, H.; Matt, G.; McBride, N.;
   Mocker, A.; Lamy, P.; Linkert, D.; Linkert, G.; Lura, F.; McDonnell,
   J. A. M.; Möhlmann, D.; Morfill, G. E.; Postberg, F.; Roy, M.;
   Schwehm, G. H.; Spahn, F.; Svestka, J.; Tschernjawski, V.; Tuzzolino,
   A. J.; Wäsch, R.; Grün, E.
2006P&SS...54..967S    Altcode:
  In July 2004 the Cassini-Huygens mission reached the Saturnian system
  and started its orbital tour. A total of 75 orbits will be carried
  out during the primary mission until August 2008. In these four years
  Cassini crosses the ring plane 150 times and spends approx. 400 h
  within Titan's orbit. The Cosmic Dust Analyser (CDA) onboard Cassini
  characterises the dust environment with its extended E ring and
  embedded moons. Here, we focus on the CDA results of the first year
  and we present the Dust Analyser (DA) data within Titan's orbit. This
  paper does investigate High Rate Detector data and dust composition
  measurements. The authors focus on the analysis of impact rates, which
  were strongly variable primarily due to changes of the spacecraft
  pointing. An overview is given about the ring plane crossings and the
  DA counter measurements. The DA dust impact rates are compared with
  the DA boresight configuration around all ring plane crossings between
  June 2004 and July 2005. Dust impacts were registered at altitudes
  as high as 100 000 km above the ring plane at distances from Saturn
  between 4 and 10 Saturn radii. In those regions the dust density of
  particles bigger than 0.5μm can reach values of 0.001m<SUP>-3</SUP>.

---------------------------------------------------------
Title: On the mechanisms leading to orphan meteoroid streams
Authors: Vaubaillon, J.; Lamy, P.; Jorda, L.
2006MNRAS.370.1841V    Altcode: 2006MNRAS.tmp..735V
  We analyse several mechanisms capable of creating orphan meteoroid
  streams (OMSs) for which a parent has not been identified. OMSs
  have been observed as meteor showers since the XIXth century and by
  the IRAS satellite in the 1980s. We find that the process of close
  encounters with giant planets (particularly Jupiter) is the most
  efficient mechanism to create them: only a limited section of the
  stream is perturbed and follows the parent body on its new orbit,
  while the majority of the meteoroids remain in their pre-encounter
  orbit or in an intermediate state, breaking the link with their
  parent body. Cometary non-gravitational forces can also contribute
  to the process since they cause the comet to drift away from its
  stream. However, they are not sufficient by themselves to produce an
  OMS. Resonances can either split or confine a stream over a long time
  (&gt;1000 yr). Some meteoroid streams may look like OMSs since their
  parent comet is dormant or not observable (e.g. long period). Even if
  new techniques succeed in linking minor objects to meteoroid streams,
  OMSs will still exist simply because cometary nuclei are subject to
  complete disruption leading to their disappearance.

---------------------------------------------------------
Title: Analysis of Space Coronagraphic Images : Application to ten
    years of SOHO/LASCO data
Authors: Burtin, M.; Llebaria, A.; Lamy, P.
2006ASPC..351..275B    Altcode: 2006adass..15..275B
  Since 1996, the LASCO (Large Angle and Spectrometric Coronagraph)
  Coronagraphs of the ESA/NASA SOHO (Solar and Heliospheric
  Observatory) mission have been providing the solar astronomical
  and geophysical communities with an unprecedented view of the solar
  corona. The photometric restitution of the huge amount of data is
  of prime importance for understanding the physics of the corona,
  its evolution over a solar cycle as well as its consequences on the
  Earth environment, and represents a major challenge. The combination
  of ground calibrations, continuous in-flight calibrations and the
  implementation of novel procedures has been necessary to disentangle
  the strong intercorrelation between many instrumental effects such
  as vignetting, polarization, straylight, optical distortion and
  timing. Geometricals parameters are extracted in a first pass. The
  vignetting correction relies on a detailed model of the instrument
  supplemented by a comparison with ground-based observations of the
  inner corona during the 1998 total eclipse. The polarimetric response
  based on the Mueller method was finely corrected thanks to polarized
  images obtained during specific maneuvers of the SOHO spacecraft. The
  straylight has been deduced on a yearly basis using the unpolarized
  component extracted from polarization sequences. The photometric
  calibration and its temporal evolution relies on several hundreds stars
  observed over ten years of operation. We will describe the overall
  software and database architectures of these calibration-pipeline
  chains, and the final products made available on our LASCO website.

---------------------------------------------------------
Title: Magnetic Variability of the Streamer Belt
Authors: Saez, F.; Lamy, P.; Llebaria, A.
2006ESASP.617E..74S    Altcode: 2006soho...17E..74S
  No abstract at ADS

---------------------------------------------------------
Title: Interaction of CMEs with the Streamer Belt
Authors: Llebaria, A.; Saez, F; Lamy, P.; Robelus, S.; Boursier, Y.
2006ESASP.617E.135L    Altcode: 2006soho...17E.135L
  No abstract at ADS

---------------------------------------------------------
Title: The Marseille-Artemis Catalog of LASCO CMES
Authors: Boursier, Y.; Lamy, P.; Llebaria, A.; Robelus, S.
2006ESASP.617E.119B    Altcode: 2006soho...17E.119B
  No abstract at ADS

---------------------------------------------------------
Title: Formation flying applied to solar coronal diagnostics: the
    ASPIICS coronagraph
Authors: Vivès, S.; Lamy, P.; Levacher, P.; Boit, J. L.; Saisse, M.
2006SPIE.6265E..24V    Altcode: 2006SPIE.6265E..64V
  Classical externally-occulted coronagraphs are presently limited in
  their performances by the distance between the external occulter
  and the front objective. The diffraction fringe from the occulter
  and the vignetted pupil which degrades the spatial resolution
  prevent observing the inner corona inside typically 2-2.5 solar
  radii. Formation flyers open new perspectives and allow to conceive
  giant, externally-occulted coronagraphs using a two-component space
  system with the external occulter on one spacecraft and the optical
  instrument on the other spacecraft at approximately 100-150 m from
  the first one. ASPIICS (Association de Satellites Pour l'Imagerie et
  l'Interfromtrie de la Couronne Solaire) is a payload proposed to ESA
  in the framework of the PROBA-3 mission of formation flyers presently
  under study. ASPIICS is composed of a single coronagraph which performs
  high spatial resolution imaging of the corona as well as 2-dimensional
  spectroscopy of several emission lines (in particular the forbidden line
  of Fe XIV at 530.285 nm) from the coronal base out to 3 solar radii (
  R <SUB>solar</SUB>). Thus ASPIICS will address the main questions of
  the coronal physics. The classical design of an externally occulted
  coronagraph is adapted to the detection of the very inner corona as
  close as 1.01 R <SUB>solar</SUB> and the addition of a Fabry-Perot
  interferometer using a so-called etalon.

---------------------------------------------------------
Title: Survey of Ensemble Physical Properties of Cometary Nuclei
Authors: Fernandez, Yanga; A'Hearn, Michael; Bauer, James; Campins,
   Humberto; Groussin, Olivier; Lamy, Philippe; Licandro, Javier; Lisse,
   Carey; Lowry, Stephen; Meech, Karen; Reach, William; Toth, Imre;
   Weaver, Harold
2006sptz.prop30908F    Altcode:
  We propose to make an albedo and radius survey of 100 cometary nuclei
  using IRS PU and MIPS imaging. We focus on Jupiter family comets
  (JFCs), which have dynamical and evolutionary connections to other
  Solar System groups: transneptunian objects (TNOs), Centaurs, Trojan
  asteroids, and extinct comet candidates. However, among these groups,
  the nuclei of JFCs remain the _only_ group not yet the subject of a
  detailed mid-infrared survey. Understanding the evolution of comets
  since formation is crucial for unlocking their secrets about the
  thermophysical and compositional environment of the protoplanetary
  disk. An important way to do this is to study comparisons and contrasts
  among comets, and between comets and related dynamical groups. To
  this end, we propose a mid-IR survey of JFCs. Our scientific goals
  are as follows. 1) Measure the thermal emission from the JFC nuclei
  to calculate their effective radii. 2) Use complementary ground-based
  visible-wavelength observations to derive the nuclei's geometric
  albedos. Note that simultaneity for these observations is not needed. 3)
  Compare the cometary albedo distribution with those of Centaurs, TNOs,
  Trojans, and extinct comet candidates to gauge the effects of surface
  evolution. The glaring albedo difference between TNOs and Centaurs
  versus other groups needs to be explained. 4) Test for correlations
  between cometary albedos and other properties of the nuclei, such
  as composition and dynamical age. 5) Resolve once and for all the
  long-standing question of just how safe it is to assume an albedo for
  a cometary nucleus. 6) Use these radii to derive a completely new and
  independent estimate of the current JFC size distribution that will
  resolve the ongoing debate between several groups. The number of targets
  in our sample is driven by the need to test recent indications that
  the size distribution is truncated at radii smaller than 2 km. In such
  a case, ours would be the definitive study of the JFC size distribution.

---------------------------------------------------------
Title: Photometric calibration of the LASCO-C2 coronagraph for Solar
    System objects
Authors: Llebaria, A.; Lamy, P.; Danjard, J. -F.
2006Icar..182..281L    Altcode:
  We present a photometric calibration of the SOHO/LASCO-C2 coronagraph
  appropriate to Solar System objects based on the extensive analysis
  of all stars down to magnitude V=8 which transited its field-of-view
  during the past nine years of operation (1996-2004). An automatic
  procedure was developed to analyze some 143,000 images, and to detect,
  locate and measure those stars. Aperture photometry was performed
  using three different aperture sizes and the zero points of the
  photometric transformations between the LASCO-C2 magnitudes for its
  three filters (orange, blue and red) and the standard V magnitudes
  were determined after introducing a correction for the color of the
  stars. The calibration coefficients for the surface photometry of
  extended sources were then derived from the zero points. An analysis of
  their temporal evolution indicates a slight decrease of the sensitivity
  of LASCO-C2 at a rate of ∼0.7% per year.

---------------------------------------------------------
Title: Calibration of the Soho/Lasco C3 White Light Coronagraph
Authors: Morrill, J. S.; Korendyke, C. M.; Brueckner, G. E.; Giovane,
   F.; Howard, R. A.; Koomen, M.; Moses, D.; Plunkett, S. P.; Vourlidas,
   A.; Esfandiari, E.; Rich, N.; Wang, D.; Thernisien, A. F.; Lamy, P.;
   Llebaria, A.; Biesecker, D.; Michels, D.; Gong, Q.; Andrews, M.
2006SoPh..233..331M    Altcode:
  We present a detailed review of the calibration of the LASCO C3
  coronagraph on the SOHO satellite. Most of the calibration has been
  in place since early in the mission and has been utilized to varying
  degrees as required by specific analysis efforts. However, using
  observational data from the nearly decade-long database of LASCO images,
  we have re-evaluated and improved many aspects of the calibration. This
  includes the photometric calibration, vignetting function, geometric
  distortion, stray light, and exposure and observation times. Using this
  comprehensive set of corrections we have generated and made available a
  set of calibrated coronal images along with a set of periodic background
  images to ease the accessibility and use of the LASCO database.

---------------------------------------------------------
Title: 3D Simulations of the Solar Corona using Octree Compression
Authors: Saez, F.; Lamy, P.; Llebaria, A.
2006IAUS..233..236S    Altcode:
  We present a new powerful tool to simulate the streamer belt of the
  solar corona based on forward modeling. It takes into account the
  temporal evolution of the corona and provides both qualitative and
  quantitative results. Starting from the National Solar Observatory
  photospheric magnetograms, the position of the neutral line at the
  source surface (2.5 Rsun) is caculated using the potential field source
  surface model. The plasma sheet of the streamer belt is centered around
  the current sheet represented as the radial extension of the neutral
  line. The 3D electron density is represented with octree compression and
  the radiance images are computed by a ray-tracing algorithm implementing
  the Thomson scattering. A multi-octree method allows to simulate the
  temporal evolution of the streamer belt and to compute the synoptic
  maps from time-series of generated images. The comparison between the
  synoptic maps of the streamer belt obtained with the SOHO/LASCO-C2
  coronagraph and the simulated synoptic maps constructed from our model
  shows a global agreement for both radiance profiles and global behaviour
  of the streamer and confirms earlier findings by Wang et al. (1997) that
  the streamers are associated with folds in the plasma sheet. However,
  some features cannot be explained using this method and are interpreted
  by introducing two types of large-scale structures. Our results suggest
  that the potential field source surface model is not fully adequate
  for the description of the fine structure of the streamer belt, even
  during the time of low solar activity. We present new applications of
  our method to future coronographic observations with SECCHI/COR-2 on
  STEREO and SILC on Solar Orbiter.

---------------------------------------------------------
Title: ASPIICS, a giant externally occulted coronagraph for the
    PROBA-3 formation flyer mission
Authors: Vivès, S.; Lamy, P.; Koutchmy, S.; Arnaud, J.
2006cosp...36.3063V    Altcode: 2006cosp.meet.3063V
  Formation flyers open new perspectives and allow to conceive giant
  externally-occulted coronagraphs using a two-component space system with
  the external occulter on one spacecraft and the optical instrument on
  the other spacecraft at approximately 100 m from the first one ASPIICS
  Association de Satellites Pour l Imagerie et l Interferometrie de la
  Couronne Solaire is a mission proposed to ESA in the framework of the
  PROBA-3 program of formation flyers which is presently in phase A to
  exploit this technique for coronal observations ASPIICS is composed of
  a single coronagraph which performs high spatial resolution imaging of
  the corona as well as 2-dimensional spectroscopy of several emission
  lines from the coronal base out to 3 Rs The selected lines allow to
  address different coronal regions the forbidden line of FeXIV at 530
  285 nm coronal matter Fe IX X at 637 4 nm coronal holes HeI at 587
  6 cold matter An additional broad spectral channel will image the
  white light corona and derive electron densities The classical design
  of an externally occulted coronagraph is adapted to the detection
  of the very inner corona as close as 1 01 Rs and the addition of
  a Fabry-Perot interferometer using a so-called etalon ASPIICS will
  address the question of the coronal heating and the role of waves by
  characterizing propagating fluctuations waves and turbulence in the
  solar wind acceleration region and by looking for oscillations in the
  intensity and Doppler shift of spectral lines The combined imaging
  and spectral diagnostics capabilities available with ASPIICS

---------------------------------------------------------
Title: A portrait of the nucleus of comet 67P/Churyumov-Gerasimenko,
    the target of the Rosetta mission
Authors: Lamy, P.; Toth, I.; Jorda, L.; Lowry, S.; Gutierrez, P.;
   Groussin, O.; Kaasalainen, M.
2006cosp...36.3366L    Altcode: 2006cosp.meet.3366L
  We present a detailed portrait of the nucleus of comet 67P
  Churyumov-Gerasimenko based on observations performed with the Hubble
  Space Telescope with the Spitzer Space Telescope and with the ESO New
  Technology Telescope in Chili In all cases the observations extended
  over several hours so that light curves could be secured Results will
  encompass the size shape albedo and rotational state of the nucleus
  of 67P as well as a 3D solution reconstruction of its shape resulting
  from the inversion of the light curves

---------------------------------------------------------
Title: Properties of the DEEP IMPACT Dust Cloud
Authors: Jorda, L.; Lamy, P.; Faury, G.; Keller, H. -U.; Kueppers,
   M.; Hviid, S.; Koschny, D.; Lecacheux, J.; Gutierrez, P.; Lara, L.
2006cosp...36.3223J    Altcode: 2006cosp.meet.3223J
  The OSIRIS Narrow Angle Camera aboard ROSETTA observed in the visible
  the dust cloud created by the DEEP IMPACT impactor during more than
  2 weeks Additional observations were also obtained at Pic du Midi
  Observatory in the visible before and after the impact We compare the
  acquired images with synthetic images resulting from a Monte-Carlo
  simulation to compute the mass and the kinetic energy of the dust in
  the cloud We also derive the size mass and velocity distributions
  of the dust particles Our study is however restricted to submicron
  particles which can be easily detected on our images

---------------------------------------------------------
Title: Electron density in polar and trans-equatorial coronal
    holes. Implications for the solar wind
Authors: Lamy, P.; Saez, F.; Llebaria, A.
2006cosp...36.3338L    Altcode: 2006cosp.meet.3338L
  We present the final analysis of the polarized images of the solar
  corona obtained with the LASCO-C2 coronagraph aboard SOHO over the
  last 10 years The calibrated polarized radiance pB has been inverted to
  produce 2-D maps of the electron density assuming either spherical or
  cylindrical symmetry We concentrate here on polar and trans-equatorial
  coronal holes We compare the measured profiles with those from models
  and past observations We attempt to determine the lowest possible
  density profile in a hole We finally discuss the implications of our
  measurements for the properties of the solar wind

---------------------------------------------------------
Title: The Coronal Dynamics Imagers for the KUAFU mission
Authors: Vivès, S.; Lamy, P.; Rousset, G.; Boit, J. -L.
2006cosp...36.3054V    Altcode: 2006cosp.meet.3054V
  The Space Weather Explorer - KuaFu mission will provide simultaneous
  long-term and synoptic observations of the complete chain of
  disturbances from the solar atmosphere to the geospace KuaFu-A located
  at the L1 liberation point includes Coronal Dynamics Imagers composed
  of a Lyman-alpha coronagraph from 1 1 to 2 5 solar radii and a white
  light coronagraph out to 15 solar radii in order to identify the
  initial sources of Coronal Mass Ejections CMEs and their acceleration
  profiles The difficulty of observing the lower corona should not be
  underestimated since instrumental stray light remains a critical issue
  in the visible because of the low contrast of the corona with respect
  to the Sun Observing the corona in the Lyman-alpha line is a valid
  alternative to white light observations The Lyman-alpha approach takes
  advantage of both the intrinsic higher contrast of the corona wrt the
  solar disk in this line compared to the visible and the absence of
  F-corona at 121 6nm Furthermore it has been convincingly shown that
  the coronal structures seen in Lyman-alpha correspond to those seen in
  the visible and which result from Thomson scattering of the coronal
  ionized gas This is because the plasma is still collisional in the
  lower corona so that the hydrogen neutral atoms are coupled to the
  protons A classical internally-occulted Lyot coronagraph is required
  so as to preserve the image quality down to the inner limit of the
  field of view Following the general concept of a Lyot coronagraph the
  optical design uses only mirrors A narrow band interferential filter

---------------------------------------------------------
Title: Visible and infrared observations of Asteroid Steins, a target
    of the Rosetta mission
Authors: Lamy, P.; Barucci, A.; Jorda, L.; Lowry, S.; Carvano, J.;
   Fornasier, S.; Groussin, O.; Kaasalainen, M.
2006cosp...36.3351L    Altcode: 2006cosp.meet.3351L
  In 2008 the ROSETTA spacecraft will flyby asteroid 2867 Steins a small
  main belt asteroid whose present knowledge is still very limited In
  particular its albedo is unknown since it has never been observed in
  the infrared Its rotational period of 6 06 -0 05 hours and light curve
  amplitude of 0 2 mag have been recently determined but the orientation
  of its spin axis is unknown In order to improve our knowledge of this
  asteroid and prepare the flyby we have conducted a campaign of visible
  measurements using ground-based telescopes and infrared measurements
  using the SST Spitzer space telescope In all cases Steins has been
  observed over several hours to secure rotational light curves in order
  to rephase them for proper interpretation We will present our results
  for the size shape albedo and rotational state of this asteroid as
  well as a 3D solution reconstruction of its shape resulting from the
  inversion of the light curves

---------------------------------------------------------
Title: Understanding the Kreutz sungrazing comets
Authors: Knight, M. M.; A'Hearn, M. F.; Biesecker, D. A.; Faury, G.;
   Hamilton, D. P.; Lamy, P.; Llebaria, A.
2006cosp...36.2697K    Altcode: 2006cosp.meet.2697K
  We present the results of our study of the Kreutz family comets
  observed by SOHO-LASCO This is a continuation of earlier work by
  Biesecker et al 2002 and includes all Kreutz comets which reached
  perihelion in the SOHO-LASCO field of view by the end of 2005 a
  sample of over 900 comets We use physical models of the nucleus such
  as composition density porosity and production rates to explain the
  characteristic features of Kreutz light curves notably the slope
  of brightening the peak in brightness at 10-13 solar radii prior to
  perihelion and the rapid fading interior to this The possibility that
  there exists two distinct subgroups of Kreutz comets which reach peak
  brightness at slightly different heliocentric distances is reexamined
  and modeled We compare the Kreutz comets with other comets observed by
  SOHO-LASCO the sungrazing families Meyer Marsden and Kracht and other
  non-sungrazing comets and with observations of prominent sungrazers
  seen from the ground e g C 1965 S1 Ikeya-Seki to estimate production
  rates at larger heliocentric distances From these rates we improve the
  scaling relationship between size and apparent brightness and constrain
  the size distribution of the Kreutz family Finally we predict discovery
  rates of Kreutz comets by the upcoming STEREO mission and ground-based
  surveys such as Pan-STARRS This research was supported by NASA Planetary
  Atmospheres grant NAG513295

---------------------------------------------------------
Title: 3-D simulations of the solar Corona for the STEREO and SOLAR
    ORBITER missions
Authors: Saez, F.; Lamy, P.; Llebaria, A.
2006cosp...36.3344S    Altcode: 2006cosp.meet.3344S
  We present a new powerful tool based on a forward modeling method which
  allows to simulate the streamer belt taking into account the temporal
  evolution of the solar corona and which provides both qualitative and
  quantitative results Starting from the NSO photospheric magnetograms the
  position of the neutral line at the source surface 2 5 Rsun is caculated
  using the potential field source surface model The plasma sheet of
  the streamer belt is centered around the current sheet represented
  as the radial extension of the neutral line The 3-D electron density
  is represented with octree compression and the radiance images are
  computed by a ray-tracing algorithm implementing the Thomson scattering
  A multi-octree method permits to simulate the temporal evolution of
  the streamer belt This method has now been generalized to hanble the
  plumes and the coronal mass ejections and is well adapted to multi-views
  of the corona such as will be offered by the STEREO mission and to
  out-of-ecliptic views that SOLAR ORBITER will achieve We will present
  synthetic images as expected from the coronagraphs of these missions

---------------------------------------------------------
Title: The Lyman Alpha Imaging-Monitor Experiment (LAIME) for
    TESIS/CORONAS-PHOTON
Authors: Damé, L.; Koutchmy, S.; Kuzin, S.; Lamy, P.; Malherbe,
   J. -M.; Noëns, J. -C.
2006cosp...36.3524D    Altcode: 2006cosp.meet.3524D
  LAIME the Lyman Alpha Imaging-Monitor Experiment is a remarkably
  simple no mechanisms and compact 100x100x400 mm full Sun imager to be
  flown with TESIS on the CORONAS-PHOTON mission launch expected before
  mid-2008 As such it will be the only true chromospheric imager to be
  flown in the next years supporting TESIS EUV-XUV imaging SDO and the
  Belgian LYRA Lyman Alpha flux monitor on the ESA PROBA-2 microsatellite
  launch expected in September 2007 We will give a short description
  of this unique O60 mm aperture imaging telescope dedicated to the
  investigating of the magnetic sources of solar variability in the UV and
  chromospheric and coronal disruptive events rapid waves Moreton waves
  disparitions brusques of prominences filaments eruptions and CMEs onset
  The resolution pixel is 2 7 arcsec the field of view 1 4 solar radius
  and the acquisition cadence could be as high as 1 image minute The back
  thinned E2V CCD in the focal plane is using frame transfer to avoid
  shutter and mechanisms Further more the double Lyman Alpha filtering
  allows a 40 AA FWHM bandwidth and excellent rejection yet providing
  a vacuum seal design of the telescope MgF2 entrance window Structural
  stability of the telescope focal length 1 m is preserved by a 4-INVAR
  bars design with Aluminium compensation in a large pm 10 o around 20 o

---------------------------------------------------------
Title: Combined Visible Observations Of Comet 9P/Tempel 1 During
    The Deep Impact Event From Pic du Midi Observatory And With The
    ROSETTA/OSIRIS Narrow Angle Camera
Authors: Jorda, L.; Lamy, P. L.; Faury, G.; Gutierrez, P.; Keller,
   H. -U.; Kueppers, M.; Lecacheux, J.; Colas, F.; Hviid, S.; Lara,
   L. M.; OSIRIS Team
2005DPS....37.4414J    Altcode: 2005BAAS...37.1568J
  We observed comet 9P/Tempel 1 before and after the impact in the visible
  from the Earth with the 1-m telescope at Pic du Midi Observatory
  and with the narrow angle camera (OSIRIS/NAC) aboard the ROSETTA
  spacecraft. The latter observations allowed an uninterrupted monitoring
  from 120 hrs pre-impact to 250 hrs post-impact, but at a low spatial
  resolution (1 pixel projected to 1500 km at the comet). The former
  observations offered a less extensive temporal coverage (about 3 hrs
  per night from June 25 to July 7) but at a higher spatial resolution
  (1 pixel projected to 600 km at the comet). The angle of 27 degrees
  between the two lines-of-sight further allowed to follow the same event
  from two different viewing angles. We present a combined preliminary
  analysis of the images obtained with both instruments. The dust
  production rate is monitored via two proxies, the [Afrho] parameter
  and the dust cross section, which is more appropriate in the case of a
  non-canonic coma. This indicates that the comet went back to its normal,
  pre-impact state within about 7 days of the impact thus showing that
  it did not create a detectable active region. Dust structures were
  found and followed in the coma and in the dust tail and we discuss
  their significance. Several spectral analysis of the pre-impact light
  curve reveal a periodic variation attributed to the rotation of the
  nucleus with a period of about 41 hrs.

---------------------------------------------------------
Title: The rotational state of the nucleus of comet 9P/Tempel 1
Authors: Lamy, P. L.; Toth, I.; A'Hearn, M. F.; Weaver, H. A.
2005DPS....37.4411L    Altcode: 2005BAAS...37Q1568L
  The nucleus of comet 9P/Tempel 1 was observed with the Hubble Space
  Telescope Advanced Camera for Surveys (HST/ACS) in May 2004, in an
  effort to pin down its rotational period and assist in the preparation
  of the operations of the Deep Impact mission. The observations were
  performed from May 7.9 to 9.5, 2004, and extended over a 39-hour
  period. At the mid-point of the observing window, the comet was 3.52
  AU from the Sun , 4.03 AU from the Earth and at a phase angle of 13.5
  deg. The program consisted in 18 separate visits, each one corresponding
  to an HST orbit and including 3 identical exposures of 857 sec duration
  with the F606W broadband filter. These very deep exposures revealed a
  point-source object, albeit the nucleus, without any coma. Photometry
  was performed by PSF fitting, the required (model) PSFs being generated
  with the TinyTim software. The mean V magnitude of the nucleus was
  21.85 and had an amplitude of 0.45 mag indicating that we were seeing
  the varying cross-section of a rotating, elongated body. There is a
  very clear asymmetry between the two half-periods of the light curve
  with one minimum being much deeper than the other. The periodicity was
  analyzed with six different techniques yielding a rotational period in
  the range 38.32 to 42.68 hr, and resulting in a mean value of 41.0 hr.

---------------------------------------------------------
Title: The colors of cometary nuclei and other primitive bodies
Authors: Toth, I.; Lamy, P. L.
2005DPS....37.1617T    Altcode: 2005BAAS...37.1563T
  Primitive minor objects like Kuiper-belt objects (KBOs), Centaurs,
  cometary nuclei and low-albedo asteroids contain a considerable
  amount of information regarding the formation of early solar system
  planetesimals and some of the primordial processes. Broadband colors
  by themselves offer limited insight into surface composition but
  correlations either between different color indices or with other
  (e.g., orbital) parameters can shed some light on the questions of
  the composition and the evolution of the minor objects. Furthermore,
  a systematic comparison of the color indices of various populations may
  provide clues on their relationships, and concur along with dynamical
  studies, to establish a scenario of their formation and evolution in the
  solar system. We present new color results on cometary nuclei obtained
  with the Hubble Space Telescope (HST) whose superior resolution enables
  us to accurately isolate the nucleus signals from the surrounding
  comae. By combining with scrutinized available data obtained with
  ground-based telescopes, we accumulated a sample of 39 cometary nuclei,
  34 ecliptic comets (ECs) and 5 nearly-isotropic comets (NICs) using
  the nomenclature of Levison (1996). We analyze color distributions and
  color-color correlations as well as correlations with other physical
  parameters. We present our own compilation of colors of 282 objects in
  the outer solar system, separately considering the different dynamical
  populations, classical KBOs in low and high-inclination orbits,
  resonant KBOs (practically Plutinos), scattered-disk objects (SDOs)
  and Centaurs. We perform a systematic analysis of color distributions
  of all plausible parent-child combinations and conclude by synthesizing
  the implications of the colors for the origin of ecliptic comets. <P
  />We acknowledge the support of the French "Programme National de
  Planétologie", jointly funded by CNRS and CNES, and of the bilateral
  French--Hungarian cooperation program. I. Toth further acknowledges
  the support of the Université de Provence, of the Hungarian Academy
  of Sciences through grant No. 9871.

---------------------------------------------------------
Title: Hubble Space Telescope observations of the nucleus fragment
    73P/Schwassmann Wachmann 3-C
Authors: Toth, I.; Lamy, P.; Weaver, H. A.
2005Icar..178..235T    Altcode:
  The investigation of fragmented comets provides information on the
  physical properties and internal structure of cometary nuclei, as well
  as insights into the mechanisms responsible for cometary breakups. The
  Jupiter-family Comet 73P/Schwassmann-Wachmann 3 (73P/SW3) fragmented
  non-tidally into at least four components, and probably more, in the
  autumn of 1995. Fragment C was detected with the Wide Field Planetary
  Camera 2 (WFPC2) of the Hubble Space Telescope (HST) on 26 November
  2001 when it was 3.26 AU from the Sun and 2.34 AU from the Earth. The
  high spatial resolution of the HST allowed us to separate the signal of
  the fragment from that of its coma, and to determine its R magnitude in
  the Johnson-Kron-Cousins photometric system from four images taken with
  the F675W filter. Assuming a spherical body with a geometric albedo
  of 0.04 and a linear phase coefficient of 0.04 mag deg <SUP>-1</SUP>
  for the R band, we derived an effective radius of 0.68±0.04km. The
  pre-breakup radius of the original nucleus was estimated to be 1.1 km,
  which implies that the volume of fragment C is ∼25% of the total
  volume of the pre-breakup nucleus. The limited temporal coverage of
  our observations preclude deriving an accurate shape or rotational
  period; our measurements are consistent with a rather spherical body
  but an elongated shape cannot be excluded. Fragment C was very active
  despite its rather large heliocentric distance, with an estimated dust
  production rate of ∼1.5kgs (∼130 metric tons day <SUP>-1</SUP>). A
  very large fraction of the surface area of fragment C must have been
  sublimating to sustain such a high level of activity. Fragment C may
  be recovered at its next return in 2006, if it does not experience
  further fragmentation.

---------------------------------------------------------
Title: On the 3-dimensional structure of the streamer belt of the
    solar corona
Authors: Saez, F.; Zhukov, A. N.; Lamy, P.; Llebaria, A.
2005A&A...442..351S    Altcode:
  We investigate the three-dimensional structure of the streamer belt
  of the solar corona using a model that allows us to simulate its
  quasi-stationary configuration. Starting from the National Solar
  Observatory photospheric magnetograms, the position of the neutral
  line at the source surface (2.5 ~R_⊙) is determined using the
  potential field source surface model. A plasma sheet is centered
  around the current sheet represented as the radial extension of
  the neutral line. Comparing the synoptic maps of the streamer belt
  obtained with the SOHO/LASCO-C2 coronagraph and the simulated synoptic
  maps constructed from our model of the warped plasma sheet, we confirm
  earlier findings by Wang et al. (1997, ApJ, 485, 875; Wang et al. 2000,
  Geophys. Res. Lett., 27, 149) that the streamers are associated with
  folds in the plasma sheet. Although the large-scale structure of the
  streamer belt is described reasonably well, some features, however,
  cannot be explained in this framework. We propose that two types of
  large-scale structures take part in the formation of these additional
  features. The first one is an additional fold of the neutral line, which
  does not appear in the modeled source surface neutral line, but is well
  visible in photospheric magnetograms. The second one is a plasma sheet
  with a ramification in the form of a secondary short plasma sheet. We
  show that these structures better describe the observed configurations
  of the streamer belt. The secondary plasma sheet can be formed between
  two secondary current sheets connected to the main current sheet. Our
  results suggest that the potential field source surface model is
  not fully adequate for the description of the fine structure of the
  streamer belt, even during the time of low solar activity.

---------------------------------------------------------
Title: A large dust/ice ratio in the nucleus of comet 9P/Tempel 1
Authors: Küppers, Michael; Bertini, Ivano; Fornasier, Sonia;
   Gutierrez, Pedro J.; Hviid, Stubbe F.; Jorda, Laurent; Keller,
   Horst Uwe; Knollenberg, Jörg; Koschny, Detlef; Kramm, Rainer; Lara,
   Luisa-Maria; Sierks, Holger; Thomas, Nicolas; Barbieri, Cesare; Lamy,
   Philippe; Rickman, Hans; Rodrigo, Rafael; A'Hearn, M. F.; Angrilli,
   F.; Bailey, M.; Barthol, P.; Barucci, M. A.; Bertaux, J. -L.; Burns,
   J. A.; Cremonese, G.; Curdt, W.; De Cecco, M.; Debei, S.; Fulle, M.;
   Gliem, F.; Ip, W. H.; Huhrt, E.; Llebaria, A.; Lopez Moreno, J. J.;
   Marzari, F.; Naletto, G.; Sabau, L.; Sanz Andres, A.; Sivan, J. P.;
   Tondello, G.; Wenzel, K. -P.
2005Natur.437..987K    Altcode:
  Comets spend most of their life in a low-temperature environment
  far from the Sun. They are therefore relatively unprocessed and
  maintain information about the formation conditions of the planetary
  system, but the structure and composition of their nuclei are poorly
  understood. Although in situ and remote measurements have derived
  the global properties of some cometary nuclei, little is known about
  their interiors. The Deep Impact mission shot a projectile into comet
  9P/Tempel 1 in order to investigate its interior. Here we report the
  water vapour content (1.5 × 10<SUP>32</SUP> water molecules or 4.5 ×
  10<SUP>6</SUP>kg) and the cross-section of the dust (330km<SUP>2</SUP>
  assuming an albedo of 0.1) created by the impact. The corresponding
  dust/ice mass ratio is probably larger than one, suggesting that
  comets are `icy dirtballs' rather than `dirty snowballs' as commonly
  believed. High dust velocities (between 110ms<SUP>-1</SUP> and
  300ms<SUP>-1</SUP>) imply acceleration in the comet's coma, probably
  by water molecules sublimated by solar radiation. We did not find
  evidence of enhanced activity of 9P/Tempel 1 in the days after the
  impact, suggesting that in general impacts of meteoroids are not the
  cause of cometary outbursts.

---------------------------------------------------------
Title: Deep Impact Observations by OSIRIS Onboard the Rosetta
    Spacecraft
Authors: Keller, Horst Uwe; Jorda, Laurent; Küppers, Michael;
   Gutierrez, Pedro J.; Hviid, Stubbe F.; Knollenberg, Jörg; Lara,
   Luisa-Maria; Sierks, Holger; Barbieri, Cesare; Lamy, Philippe; Rickman,
   Hans; Rodrigo, Rafael
2005Sci...310..281K    Altcode:
  The OSIRIS cameras (optical, spectroscopic, and infrared remote imaging
  system) onboard the European Space Agency's Rosetta spacecraft observed
  comet 9P/Tempel 1 for 17 days continuously around the time of NASA's
  Deep Impact mission. The cyanide-to-water production ratio was slightly
  enhanced in the impact cloud, compared with that of normal comet
  activity. Dust particles were flowing outward in the coma at &gt;160
  meters per second, accelerated by the gas. The slope of the brightness
  increase showed a dip about 200 seconds after the impact. Dust Afρ
  values before and long after the impact confirm the slight decrease of
  cometary activity. The dust-to-water mass ratio was much larger than 1.

---------------------------------------------------------
Title: Outgassing-induced effects in the rotational state of comet
    67P/Churyumov—Gerasimenko during the Rosetta mission
Authors: Gutiérrez, Pedro J.; Jorda, Laurent; Samarasinha, Nalin H.;
   Lamy, Philippe
2005P&SS...53.1135G    Altcode:
  The new target of the Rosetta mission is comet 67P/Churyumov-Gerasimenko
  (hereafter 67P/C-G). In order to support the planning of the mission,
  in particular the strategy during the mapping and landing phases, we
  have performed numerical simulations of the rotational evolution of a
  comet in the orbit of 67P/C-G. In these simulations, the currently known
  observational constraints have been taken into account and a large set
  of initial conditions were considered. For most of the simulations,
  we observe that the sublimation-induced torques produce significant
  changes in the rotational parameters of a 67P/C-G-like comet. Typical
  rates of change for the spin period from the rendezvous up to the
  end of the nominal mission range from 0.001 to 0.05hday<SUP>-1</SUP>
  depending on different circumstances as described in the text. At
  perihelion, rates of change of the orientation of the angular momentum
  vector amount to about 0.01- 0.1degday<SUP>-1</SUP>. These simulations
  suggest that a specific strategy should be defined in order to monitor
  likely variations of the rotational parameters. As an example we
  show a possible optimized schedule for observations with the OSIRIS
  instrument to determine the rotational parameters of comet 67P/C-G
  and their possible evolution.

---------------------------------------------------------
Title: Formation flyers applied to solar coronal observations:
    the ASPICS mission
Authors: Vives, S.; Lamy, P.; Auchere, F.; Vial, J. -C.; Koutchmy,
   S.; Arnaud, J.; Prado, J. -Y.; Frassetto, F.; Naletto, G.
2005SPIE.5901..305V    Altcode:
  Classical externally-occulted coronagraphs are presently limited in
  their performances by the distance between the external occulter and
  the front objective. The diffraction fringe from the occulter and the
  vignetted pupil which degrades the spatial resolution prevent observing
  the inner corona inside typically 2-2.5 solar radii. Formation flyers
  open new perspectives and allow to conceive giant, externally-occulted
  coronagraphs using a two-component space system with the external
  occulter on one spacecraft and the optical instrument on the
  other spacecraft at approximately 100 m from the first one. ASPICS
  (Association de Satellites Pour l'Imagerie Coronographique Solaire)
  is a mission proposed to CNES in the framework of their demonstration
  program of formation flyers which is presently under study to exploit
  this technique for coronal observations. In the baseline concept,
  ASPICS includes three coronagraphs operating in three spectral
  domains: the visible continuum (K-corona brightness), the HI Lyman
  alpha emission line at 121.6 nm, and the HeII emission line at 30.4
  nm. Their unvignetted fields of view extend from 1.1 to 3.2 solar radii
  with a typical spatial resolution of 3 arcsec. In order to connect
  coronal activity to photospheric events, ASPICS further includes
  two disk imagers. The first one is devoted to the HI Lyman alpha
  emission line. The second one is a multi-channel instrument similar to
  SOHO/EIT and devoted to the HeII (30.4 nm), FeIX/X (17.1 nm) and FeXII
  (19.5 nm) emission lines. Two concepts of the space system are under
  consideration: a symmetric configuration where the disk imagers and
  the external occulter are on one spacecraft and the coronagraphs on
  the other, an asymmetric configuration where the external occulter is
  on one spacecraft and the scientific instruments are regrouped on the
  other one.

---------------------------------------------------------
Title: Possible optical design for ASPICS, a formation-flyer solar
    coronagraph for close-limb visible and Lyman-α imaging of the corona
Authors: Frassetto, Fabio; Naletto, Giampiero; Vives, Sebastien;
   Lamy, Philippe
2005SPIE.5901..316F    Altcode:
  The recent possibility of deploying clusters of satellites in
  flight formation allows the development of a new generation of
  space instruments, and among them, of externally occulted solar
  coronagraphs. This can be implemented by introducing a large occulter
  on a first satellite, and all the remaining optical system on a second
  satellite, located in the shadow of the occulter. Since the capability
  of looking close to the solar limb is directly related to the distance
  between the external occulter and the coronagraphic objective, formation
  flyers offer the capability of a major improvement in observing the
  lower corona from space. In this paper, we describe a possible optical
  design for ASPICS, a formation flyer solar coronagraph composed of
  two satellites separated by about 100 m. The proposed dual channel
  design will allow for the first time to simultaneously observe the
  lower and intermediate corona in both visible and ultraviolet (HI
  Lyman-α line) spectral regions at a 6 arcsec/pixel scale factor with
  a single instrument.

---------------------------------------------------------
Title: Concept of formation flyer for the ASPICS solar coronagraphic
    mission
Authors: Leyre, Xavier; Sghedoni, M.; Vives, S.; Lamy, P.; Pailharey,
   E.
2005SPIE.5899..221L    Altcode:
  This paper describes a concept of a formation flyer for ASPICS
  (Association de Satellites Pour l'Imagerie et la Coronagraphie
  Solaire), a giant 100 m based, externally occulted coronagraph aimed
  at observing the inner corona (and the solar disk) in the visible and
  ultra-violet. The two-satellite formation approach, based on existing
  space systems, is composed of a Myriade micro-satellite supporting
  the occulter and a Proteus platform as the main system carrying the
  coronagraph and imager scientific instruments. Both spacecrafts are
  launched as a single composite and deployed once on orbit, preferably
  a 3-day orbit or at the L1 Lagrange point. The coronagraph satellite
  acts as the "master" and provides the main functions of the mission
  (data handling, communication, propulsion, Guidance Navigation and
  control) while the Myriade acts as the "slave". The control of the
  formation is performed in two steps: i) RF metrology for deployment
  and preliminary pointing, ii) classical optical attitude sensors and
  metrology based on diverging laser beams. This will insure the nominal
  requirement of a lateral positioning with an accuracy of 1 mm and a
  longitudinal positioning with an accuracy of 500 mm.

---------------------------------------------------------
Title: Light Curves of Kreutz Comets
Authors: Knight, M. M.; A'Hearn, M. F.; Biesecker, D. A.; Faury, G.;
   Hamilton, D. P.; Lamy, P.; Llebaria, A.
2005DPS....37.1103K    Altcode: 2005BAAS...37Q.632K
  We present the results of our study of the light curves of the Kreutz
  family comets observed by SOHO-LASCO. This is a continuation of the
  earlier work by Biesecker et al. (2002) and includes all Kreutz comets
  which reached perihelion in the SOHO-LASCO field of view by the end of
  2003, a sample of more than 600 comets. We do not see the bimodality
  of the light curves found by Biesecker et al., however we find that
  the brightest comets increase in brightness more rapidly and fade more
  slowly than fainter comets. To test if the slope of the brightening seen
  at the small heliocentric distances observed by SOHO-LASCO (inside 0.14
  AU) extends to larger distances (1-3 AU), we imaged fields statistically
  likely to contain Kreutz comets prior to their entering the SOHO-LASCO
  field of view using the Kitt Peak National Observatory 4-m telescope
  with the MOSAIC wide-field imager in January 2005. No comets were
  discovered in these fields, however they will be searched again using
  the ephemerides of all Kreutz comets that reach perihelion in the
  SOHO-LASCO field of view during May and June 2005, since some of these
  comets should have been in the observed fields. This will allow us to
  set constraints on the rate of brightening at heliocentric distances
  beyond the SOHO-LASCO field of view. <P />This work is supported by
  the NASA Planetary Atmospheres Program under grant NAG513295.

---------------------------------------------------------
Title: Automatic detection of coronal mass ejections on LASCO-C2
    synoptic maps
Authors: Boursier, Yannick; Llebaria, Antoine; Goudail, Francois;
   Lamy, Philippe; Robelus, Sebastien
2005SPIE.5901...13B    Altcode:
  The LASCO-C2 coronagraph on-board the SOHO solar observatory has
  been providing a continuous flow of coronal images for the past nine
  years. Synoptic maps for each Carrington rotation have been constructed
  from these images and offer a global view of the temporal evolution
  of the solar corona, particularly the occurrence of transient events
  such as the coronal mass ejections (CMEs), an important component of
  space weather activity. CMEs present distinct signatures on synoptic
  maps offering a novel approach to the problem of their statistical
  detection. We are presently testing several techniques of automatic
  detection based on their morphological properties. The basic procedure
  involves three steps: i) morphological characterization, ii) definition
  and application of adapted filters (optimal trade-off filters, Canny
  filter,...), iii) segmentation of the filtered synoptic maps. At this
  stage, the CMEs are detected. The efficiency of the detection of the
  various filters is estimated using the ROC curves. On-going studies
  include the classification of CMEs based on their physical properties,
  the determination of their velocities, and the question of their
  connection to the streamer belt.

---------------------------------------------------------
Title: Characterization of Asteroids 2867 Steins and 21 Lutetia,
    Targets of the Rosetta Mission
Authors: Lamy, Philippe; Barucci, Antonella; Carvano, Jorge;
   Cruikshank, Dale; Dotto, Elisabetta; Fornasier, Sonia; Fulchignoni,
   Marcello; Groussin, Olivier; Jorda, Laurent; Migliorini, Alessandra
2005sptz.prop20653L    Altcode:
  Asteroids 2867 Steins and 21 Lutetia are the new targets of the
  Rosetta mission. Our present knowledge of these two objects is still
  very limited. Their albedos are either unknown (Steins) or subject
  to question (Lutetia), with severe consequences for their sizes and
  their taxonomic classifications and their surface compositions are
  either unclear or controversial. We propose to investigate the physical
  properties (size, shape), the surface and thermal properties (albedo,
  thermal inertia, surface roughness) and surface composition of these
  two asteroids by taking advantage of the capabilities and performances
  of the Spitzer Space Telescope (SST), supplemented by ground-based
  observations. The SST observations consist in taking low resolution
  spectra with the IRS instrument over its full wavelength range 5-38
  micron. Each asteroid will be observed 14 times at time intervals of
  30 min for Steins and 40 mn for Lutetia in order to properly sample
  their light curve. The detailed knowledge of these asteroids that
  will result from our proposed program will be of critical importance
  for optimizing the flyby strategy of the Rosetta spacecraft and the
  operation of its instruments. They will later supplement the in-situ
  observations necessarily limited by the conditions of a fast flyby
  and contribute to their global characterization.

---------------------------------------------------------
Title: A Multiwavelength Investigation of Comet 73P/SW3-C
Authors: Lamy, Philippe; Weaver, Harold; Jorda, Laurent; A'Hearn,
   Michael; Toth, Imre; Groussin, Olivier; Kaasalainen, Mikko; Lowry,
   Stephem
2005sptz.prop20001L    Altcode:
  The nucleus of comet 73P/Schwassmann-Wachmann-3 experienced a non-tidal
  breakup in late 1995. The largest fragment (73P/SW3-C) survived
  its subsequent perihelion passage in 2001 and will return in 2006,
  when it will pass very close to (0.08AU) Earth. This represents an
  outstanding opportunity to characterize a fresh cometary nucleus,
  and we propose an intensive investigation using both the Hubble
  and Spitzer telescopes. Employing the technique that our group has
  developed over the past decade to characterize 31 cometary nuclei, we
  will use HST/ACS to photometrically resolve the nucleus of 73P/SW3-C
  at optical wavelengths and SST/MIPS to do the same thing at thermal
  infrared wavelengths, thereby allowing us to determine both the size
  and albedo of this fragment. We also plan to measure the lightcurve
  of 73P/SW3-C to obtain detailed shape information, and use HST/NICMOS
  to probe the composition, in particular to search for evidence of icy
  material on the fresh surface. Previous observations indicate that
  most of the remaining mass of 73P/SW3 is in the form of numerous small
  fragments. A few of those may have been captured by the C fragment,
  and the determination of their orbits would allow the first, direct
  measurement of the mass of a cometary nucleus. Thus, we will also
  perform a deep search for any possible companions to the C-fragment.

---------------------------------------------------------
Title: Deep Impact: Working Properties for the Target Nucleus   Comet
    9P/Tempel 1
Authors: Belton, Michael J. S.; Meech, Karen J.; A'Hearn, Michael F.;
   Groussin, Olivier; McFadden, Lucy; Lisse, Carey; Fernández, Yanga R.;
   Pittichová, Jana; Hsieh, Henry; Kissel, Jochen; Klaasen, Kenneth;
   Lamy, Philippe; Prialnik, Dina; Sunshine, Jessica; Thomas, Peter;
   Toth, Imre
2005SSRv..117..137B    Altcode:
  In 1998, Comet 9P/Tempel 1 was chosen as the target of the Deep Impact
  mission (A’Hearn, M. F., Belton, M. J. S., and Delamere, A., Space
  Sci. Rev., 2005) even though very little was known about its physical
  properties. Efforts were immediately begun to improve this situation by
  the Deep Impact Science Team leading to the founding of a worldwide
  observing campaign (Meech et al., Space Sci. Rev., 2005a). This
  campaign has already produced a great deal of information on the global
  properties of the comet’s nucleus (summarized in Table I) that is
  vital to the planning and the assessment of the chances of success at
  the impact and encounter. Since the mission was begun the successful
  encounters of the Deep Space 1 spacecraft at Comet 19P/Borrelly and
  the Stardust spacecraft at Comet 81P/Wild 2 have occurred yielding
  new information on the state of the nuclei of these two comets. This
  information, together with earlier results on the nucleus of comet
  1P/Halley from the European Space Agency’s Giotto, the Soviet Vega
  mission, and various ground-based observational and theoretical studies,
  is used as a basis for conjectures on the morphological, geological,
  mechanical, and compositional properties of the surface and subsurface
  that Deep Impact may find at 9P/Tempel 1. We adopt the following
  working values (circa December 2004) for the nucleus parameters of
  prime importance to Deep Impact as follows: mean effective radius =
  3.25± 0.2 km, shape irregular triaxial ellipsoid with a/b = 3.2±
  0.4 and overall dimensions of ∼14.4 × 4.4 × 4.4 km, principal axis
  rotation with period = 41.85± 0.1 hr, pole directions (RA, Dec, J2000)
  = 46± 10, 73± 10 deg (Pole 1) or 287± 14, 16.5± 10 deg (Pole 2)
  (the two poles are photometrically, but not geometrically, equivalent),
  Kron-Cousins (V-R) color = 0.56± 0.02, V-band geometric albedo =
  0.04± 0.01, R-band geometric albedo = 0.05± 0.01, R-band H(1,1,0)
  = 14.441± 0.067, and mass ∼7×10<SUP>13</SUP> kg assuming a bulk
  density of 500 kg m<SUP>-3</SUP>. As these are working values, {i.e.},
  based on preliminary analyses, it is expected that adjustments to
  their values may be made before encounter as improved estimates become
  available through further analysis of the large database being made
  available by the Deep Impact observing campaign. Given the parameters
  listed above the impact will occur in an environment where the local
  gravity is estimated at 0.027 0.04 cm s<SUP>-2</SUP> and the escape
  velocity between 1.4 and 2 m s<SUP>-1</SUP>. For both of the rotation
  poles found here, the Deep Impact spacecraft on approach to encounter
  will find the rotation axis close to the plane of the sky (aspect
  angles 82.2 and 69.7 deg. for pole 1 and 2, respectively). However,
  until the rotation period estimate is substantially improved, it will
  remain uncertain whether the impactor will collide with the broadside
  or the ends of the nucleus.

---------------------------------------------------------
Title: UVCS Observation of Sungrazer C/2001 C2: Possible Comet
    Fragmentation and Plasma-Dust Interactions
Authors: Bemporad, A.; Poletto, G.; Raymond, J. C.; Biesecker, D. A.;
   Marsden, B.; Lamy, P.; Ko, Y. -K.; Uzzo, M.
2005ApJ...620..523B    Altcode:
  In this paper we analyze SOHO Ultraviolet Coronagraph Spectrometer
  (UVCS) observations of the sungrazing comet C/2001 C2, a member of the
  Kreutz family, observed on 2001 February 7 at heliocentric distances
  of 4.98 and 3.60 R<SUB>solar</SUB>. This comet apparently went through
  sequential fragmentation events along its path: further indication of
  fragmentation processes is provided by UVCS observations, which show
  the presence of two separate tails in the 4.98 R<SUB>solar</SUB> data
  set, which we interpret as two fragments unresolved by LASCO images,
  one of which sublimates before reaching 3.60 R<SUB>solar</SUB>. The
  cometary hydrogen Lyα signal, decaying exponentially with time,
  has been interpreted in terms of the H<SUB>2</SUB>O outgassing rate
  and the interactions of coronal protons with atoms created by the
  photodissociation of water. However, one of the fragments shows an
  additional Lyα contribution, constant with time, which adds to the
  temporally decaying signal. This contribution has been ascribed to
  the sublimation of pyroxene dust grains, whose end products neutralize
  coronal protons via charge exchange processes. Hence, the two fragments
  have different composition; differences throughout the comet body may
  have been the primary cause for the comet fragmentation.

---------------------------------------------------------
Title: The SIde-Looking Coronagraph for the solar orbiter mission:
    Optical and mechanical designs
Authors: Vivès, S.; Lamy, P.; Guitton, J.; Boit, J. L.; Dargent, P.
2005AdSpR..36.1406V    Altcode:
  The SIde-Looking Coronagraph (SILC) is intented to be proposed as
  part of the payload of the Solar Orbiter mission of the European
  Space Agency. Solar Orbiter will follow elliptic orbits with a large
  range of heliocentric distance, from 0.21 to 0.6 AU, and will reach
  heliographic latitudes as high as 38°. Furthermore, the spacecraft
  will have an offset pointing capability so as to target any point
  of the solar disk. These characteristics, in addition to the severe
  thermal environment, are very restrictive for a coronagraph and lead
  us to propose an externally occulted coronagraph entirely protected
  from direct sunlight by remaining in the shadow of the spacecraft and
  looking sideways. The optical design follows the general principles
  of an externally occulted coronagraph adapted to the side-looking
  concept. Although SILC loses the full spatial coverage of the corona,
  it can observe the inner part of the corona (down to 1.5 solar radii)
  during the whole mission and compensate the off-pointing of the
  spacecraft. The optical and mechanical designs of SILC are presented
  in detail.

---------------------------------------------------------
Title: Meteoroid Streams Associated to Comets 9P/Tempel 1 and
    67P/Churyumov-Gerasimenko
Authors: Vaubaillon, J.; Lamy, P.; Jorda, L.
2004EM&P...95...75V    Altcode: 2005EM&P...95...75V
  The meteoroid streams associated to short-period comets
  9P/Tempel 1 (the target of the Deep Impact mission)<SUP>.</SUP>
  and 67P/Churyumov-Gerasimenko (the target of the Rosetta mission)
  are studied. Their structure is overwhelmingly under the control of
  Jupiter and repeated relatively close encounters cause a reversal of
  the direction of the spatial distribution of the stream relative to the
  comet* an initial stream trailing the comet as usually seen eventually
  collapses, becomes a new stream leading the comet and even splits into
  several components. Although these two comets do not produce meteor
  showers on Earth, this above feature shows that meteor storms can
  occur several years before the perihelion passage of a parent body.

---------------------------------------------------------
Title: Physical Properties of the Deep Impact Target Comet 9P/Tempel
    1 from Spitzer and Hubble Space Telescope Observations
Authors: Lisse, C. M.; A'Hearn, M. F.; Belton, M. J. S.; Fernandez,
   Y. R.; Groussin, O.; Lamy, P.; Meech, K. J.; Toth, I.; Weaver, H. A.
2004DPS....36.3402L    Altcode: 2004BAAS...36Q1148L
  Comet 9P/Tempel 1 is the target of the Deep Impact mission to
  be launched at the end of this year. Accurate knowledge of the
  physical properties of the comet's nucleus is important for mission
  success. Current published size estimates for the nucleus are uncertain
  by 50% [Fernandez et al. 2003] and the current best rotational solutions
  have periods of 22 and 42 hours [Belton and Meech, 2004]. <P />In
  Spring 2004, with the comet outside the ice line and inactive and
  inbound on the final leg before the DI encounter, we obtained 12
  spectrophotometric (7.5-40 microns) visits of the nucleus with the
  Spitzer Space Telescope over a 40 hour period in March 2004, and 18
  photometric (F606) visits over a 42 hour period in May 2004 with the
  Hubble Space Telescope. Collating these observations into lightcurves,
  we have applied rotational and thermal models [Belton et al. 2005,
  Groussin et al. 2004] to derive values for the effective radius,
  axial ratio, pole position, bulk surface albedo, active surface area,
  and thermal inertia. Initial analysis of the observations has yielded a
  nucleus with an average radius of about 3 km, an axial ratio of about 3,
  a geometric albedo of about 4%, and an active surface fraction of about
  8%. The thermal inertia is low, similar to that of other primitive
  bodies. The rotation pole orientation's J2000 RA and Dec are either
  (99<SUP>o</SUP>,-19<SUP>o</SUP>) or (60<SUP>o</SUP>,+72<SUP>o</SUP>)
  , with an error of about 4 degrees. We present the latest results of
  our observations and analysis here.

---------------------------------------------------------
Title: The Cassini Cosmic Dust Analyzer
Authors: Srama, R.; Ahrens, T. J.; Altobelli, N.; Auer, S.; Bradley,
   J. G.; Burton, M.; Dikarev, V. V.; Economou, T.; Fechtig, H.; Görlich,
   M.; Grande, M.; Graps, A.; Grün, E.; Havnes, O.; Helfert, S.; Horanyi,
   M.; Igenbergs, E.; Jessberger, E. K.; Johnson, T. V.; Kempf, S.;
   Krivov, A. V.; Krüger, H.; Mocker-Ahlreep, A.; Moragas-Klostermeyer,
   G.; Lamy, P.; Landgraf, M.; Linkert, D.; Linkert, G.; Lura, F.;
   McDonnell, J. A. M.; Möhlmann, D.; Morfill, G. E.; Müller, M.;
   Roy, M.; Schäfer, G.; Schlotzhauer, G.; Schwehm, G. H.; Spahn, F.;
   Stübig, M.; Svestka, J.; Tschernjawski, V.; Tuzzolino, A. J.; Wäsch,
   R.; Zook, H. A.
2004SSRv..114..465S    Altcode:
  The Cassini-Huygens Cosmic Dust Analyzer (CDA) is intended to
  provide direct observations of dust grains with masses between
  10<SUP>-19</SUP> and 10<SUP>-9</SUP> kg in interplanetary space and
  in the jovian and saturnian systems, to investigate their physical,
  chemical and dynamical properties as functions of the distances
  to the Sun, to Jupiter and to Saturn and its satellites and rings,
  to study their interaction with the saturnian rings, satellites and
  magnetosphere. Chemical composition of interplanetary meteoroids will
  be compared with asteroidal and cometary dust, as well as with Saturn
  dust, ejecta from rings and satellites. Ring and satellites phenomena
  which might be effects of meteoroid impacts will be compared with the
  interplanetary dust environment. Electrical charges of particulate
  matter in the magnetosphere and its consequences will be studied,
  e.g. the effects of the ambient plasma and the magnetic field on the
  trajectories of dust particles as well as fragmentation of particles
  due to electrostatic disruption.

---------------------------------------------------------
Title: The Side-Looking Coronagraph (SILC) for the Solar Orbiter
mission: optical performances
Authors: Vivès, Sébastien; Lamy, Philippe
2004ESASP.554..381V    Altcode: 2004icso.conf..381V
  The SIde-Looking Coronagraph (SILC) is one of the solar remote-sensing
  instruments proposed for the payload of the Solar Orbiter mission
  (European Space Agency, ESA). The specificities of the Solar Orbiter
  mission are very restrictive for a coronagraph: large range of
  heliocentric distance from 0.21 to 0.6 AU, offset pointing capability
  of the spacecraft, severe thermal environment of limited mass and
  volume available. To cope with them, we propose an externally occulted
  coronagraph entirely protected from direct sunlight by remaining in
  the shadow of the spacecraft and looking sideways. The optical design
  follows the general principles of an externally-occulted coronagraph
  adapted to the side-looking concept. The performances and the expected
  stray light level will be presented here together with their evolution
  as function of the heliocentric distance.

---------------------------------------------------------
Title: The August 11th, 1999 CME
Authors: Koutchmy, S.; Baudin, F.; Bocchialini, K.; Daniel, J. -Y.;
   Delaboudinière, J. -P.; Golub, L.; Lamy, P.; Adjabshirizadeh, A.
2004A&A...420..709K    Altcode:
  We present here a set of observations, space borne and ground based,
  at different wavelengths, of the solar corona at and after the time of
  the total solar eclipse of August 11{th}. It is used to consider some
  unusual features of the coronal dynamics related to a limb Coronal Mass
  Ejection (CME) observed after the total eclipse. The complementary
  aspect of simultaneous ground-based and space-borne observations
  of the corona is used to produce an accurate composite image of the
  White Light (W-L) corona before the CME. A high arch system (possibly
  a dome-like structure, with large cavities inside but without a cusp
  further out) which appeared on the eclipse W-L images, is suggested to
  be a large-scale precursor of the CME, well preceding the eruption of
  the top part of the brightest prominence recorded in W-L. This bright
  prominence is shown as a filament in absorption using the Transition
  Region And Corona Explorer (TRACE) images taken in different coronal
  lines. The analysis of the images of the Large Angle and Spectrometric
  Coronograph (LASCO) on board the Solar and Heliospheric Observatory
  (SoHO), showing the progression of the CME, is discussed in an attempt
  to make a connection with the surface event. A SoHO-EIT (Extreme
  UV Imager Telescope) image sequence details the prominence eruption
  and shows the sudden heating processes of the ejected parts. We found
  that there is no reason to assume that the huge cavity is significantly
  destabilised well before the eruption of the upper part of the low-lying
  bright twisted filament which coincides with the position of one of
  the legs of the high arch. Observations are still compatible with the
  assumption of both the break-out model and of the flux rope erupting
  model as a result of a shear or of an increasing poloıdal magnetic
  flux from below. We stress the possible role of buoyancy of the giant
  cavity as a destabilizing factor leading to the CME, noticing that some
  motion of coronal material back toward the surface can be seen during at
  least the first phase of the CME, from both EIT and LASCO observations.

---------------------------------------------------------
Title: Preliminary calibration results of the wide angle camera of
    the imaging instrument OSIRIS for the Rosetta mission
Authors: da Deppo, V.; Naletto, G.; Nicolosi, P.; Zambolin, P.; de
   Cecco, M.; Debei, S.; Parzianello, G.; Ramous, P.; Zaccariotto, M.;
   Fornasier, S.; Verani, S.; Thomas, N.; Barthol, P.; Hviid, S. F.;
   Sebastian, I.; Meller, R.; Sierks, H.; Keller, H. U.; Barbieri, C.;
   Angrilli, F.; Lamy, P.; Rodrigo, R.; Rickman, H.; Wenzel, K. P.
2004ESASP.554..191D    Altcode: 2004icso.conf..191D
  Rosetta is one of the cornerstone missions of the European Space Agency
  for having a rendezvous with the comet 67P/Churyumov-Gerasimenko
  in 2014. The imaging instrument on board the satellite is OSIRIS
  (Optical, Spectroscopic and Infrared Remote Imaging System), a
  cooperation among several European institutes, which consists of
  two cameras: a Narrow (NAC) and a Wide Angle Camera (WAC). The WAC
  optical design is an innovative one: it adopts an all reflecting,
  unvignetted and unobstructed two mirror configuration which allows
  to cover a 12°x12° field of view with an F/5.6 aperture and gives
  a nominal contrast ratio of about 10<SUP>-4</SUP>. The flight model
  of this camera has been successfully integrated and tested in our
  laboratories, and finally has been integrated on the satellite which
  is now waiting to be launched in February 2004. In this paper we are
  going to describe the optical characteristics of the camera, and to
  summarize the results so far obtained with the preliminary calibration
  data. The analysis of the optical performance of this model shows a
  good agreement between theoretical performance and experimental results.

---------------------------------------------------------
Title: The nuclei of comets 126P/IRAS and 103P/Hartley 2
Authors: Groussin, O.; Lamy, P.; Jorda, L.; Toth, I.
2004A&A...419..375G    Altcode:
  We report the detection of the nucleus of 126P/IRAS and 103P/Hartley
  2 with the Infrared Camera of the Infrared Space Observatory
  (ISOCAM). 126P/IRAS was observed on 12 November 1996, when it was at
  r_h=1.71 AU from the Sun and Δ=1.32 AU from the Earth. 103P/Hartley
  2 was observed on 5 February 1998, when it was at r_h=1.21 AU from the
  Sun and Δ=0.91 AU from the Earth. The observations were performed with
  the broadband LW10 filter centered at 11.5 μm. The spatial resolution
  was adequate to separate the thermal emission of the nuclei from
  that of their respective comae. We combined the ISOCAM observations
  with measured water production rates, using a model that considers
  a spherical nucleus with a macroscopic mosaic of small and numerous
  active and inactive regions, and we derived a radius of 1.57±0.14 km
  and an active fraction at perihelion of 0.11±0.03 for 126P/IRAS, and
  a radius of 0.71±0.13 km and an active fraction of ∼1 at perihelion
  and 0.30±0.11 at 1.11 AU post-perihelion for 103P/Hartley 2. These
  two examples illustrate the large diversity of activity pattern that
  exists among cometary nuclei. <P />Based on observations made with the
  Infrared Space Observatory, an ESA project with instruments funded
  by ESA Member States (especially the PI countries: France, Germany,
  The Netherlands and UK) and with the participation of ISAS and NASA.

---------------------------------------------------------
Title: Lessons learned from the SOHO/LASCO-C2 calibration
Authors: Llebaria, Antoine; Lamy, Philippe L.; Bout, Maurice V.
2004SPIE.5171...26L    Altcode:
  The LASCO-C2 coronagraph onboard the SOHO solar probe have been
  providing for the last seven years an unprecedented long sequence
  of coronal images at high cadence (about 75 images/day). The LASCO-C2
  calibrations included the determination of the geometric characteristics
  (attitude, distortion) as well as the photometric and photopolarimetric
  responses. Such calibrations needed resort to a complementary set
  of approaches including optical-modelling, pre-flight measures and
  in-orbit measures and monitoring. In this paper we discuss about the
  specific contribution of each of them, the example of radiometric
  calibration of LASCO-C2 is dominated by the strong vignetting induced
  by the occultors. The occultors fully mask the extended circular area
  centered on the Sun image. Due to operational constraints the vignetting
  function has been obtained using a complementary set of approaches:
  1) ray tracing, 2) the geometric convolution of diaphragms, 3) the
  measure of uniform sources in laboratory, 4) the measures in orbit
  of the stars and F-corona. Finaly the relationship of radiometry
  with geometric calibrations, strylight calibration and the log term
  stability monitoring is discussed.

---------------------------------------------------------
Title: Optical design of the Lyman alpha coronagraph for the LYOT
    microsatellite
Authors: Vives, Sebastien; Lamy, Philippe L.; Vial, Jean-Claude
2004SPIE.5171..298V    Altcode:
  The LYOT (LYman Orbiting Telescope) solar mission (proposed for a CNES
  micro-satellite) is composed of a disk imager and a coronagraph, both
  working at Lyman-α (121.6 nm). The coronagraph is internally occulted
  and all-reflective with a field-of-view of 1.2 R up to 2.5 R and high
  spatial resolution (2 pixels) amounts to 5 arcsec. The optical design
  is driven by the requirement to use a superpolished spherical mirror
  to minimize the scattered light into the instrument. The LYOT mission
  will observe the Lyman-α corona at high cadence (1 image/5 minutes)
  over a period of two years.

---------------------------------------------------------
Title: Visible, externally occulted coronagraph for Solar Orbiter
Authors: Vives, Sebastien; Lamy, Philippe L.; Korendyke, Clarence
2004SPIE.5171..131V    Altcode:
  The SIde-Looking Coronagraph (SILC) is one of the solar remote-sensing
  instruments proposed for the payload of the Solar Orbiter mission. The
  Solar Orbiter is a mission selected in September 2000 by the European
  Space Agency (ESA) for the definition study phase. The Solar Orbiter
  will describe elliptic orbits with a large range of heliocentric
  distance, from 0.21 to 0.6 AU (astronomical units), that is a factor
  3 for the geometric conditions and will reach heliographic latitudes
  as high as 38 degrees. Furthermore, the spacecraft will have offset
  pointing capability so as to target any point of the solar disk. These
  constraints (in addition to the severe thermal environment) lead
  us to propose an externally occulted coronagraph entirely protected
  from direct sunlight by remaining in the shadow of the spacecraft and
  looking sideways. The optical design follows the general principles
  of an externally-occulted coronagraph adapted to the side-looking
  concept. Although SILC loses the full spatial coverage of the corona, it
  can observe the inner part of the corona (down to 1.5R) during the whole
  mission and compensate the off-pointing of the spacecraft in the two
  directions. The performances, resulting from ray-tracing calculations,
  are presented here together with the expected stray light level.

---------------------------------------------------------
Title: Measuring the Size and Shape of Comet
    67P/Churyumov-Gerasimenko, the Target of the Rosetta Mission
Authors: Lamy, Philippe
2004sptz.prop..222L    Altcode:
  In support of the Rosetta mission, we request Director's Discretionary
  time to measure the size and shape of its target, the nucleus of
  comet 67P/Churyumov-Gerasimenko. A safe landing of the Lander package
  on its surface remains critically dependent upon its size which
  is not unambiguoulsy determined from visible photometry because of
  the uncertainty on its albedo. On the contrary, measurements of the
  thermal emission of the nucleus will allow a direct determination
  of its size. Observations with the Spitzer Space Telescope in late
  February 2004 will provide the best possible data thanks to very
  favourable observing conditions. We propose to use MIPS to image the
  nucleus at 24 microns seventeen times, over a time interval of 12.5
  hr to as to cover the full light curve of the nucleus and derive both
  its size and shape. Complementary observations at 70 microns will help
  constraining its SED and the thermal model to interpret the data. By
  further combining with past HST observations, the rotational state
  of the nucleus will be better con strained and the albedo will be
  determined thus allowing to characterize its surface.

---------------------------------------------------------
Title: The sizes, shapes, albedos, and colors of cometary nuclei
Authors: Lamy, P. L.; Toth, I.; Fernandez, Y. R.; Weaver, H. A.
2004come.book..223L    Altcode:
  We critically review the data on the sizes, shapes, albedos, and
  colors of cometary nuclei. Reliable sizes have been determined for
  65 ecliptic comets (ECs) and 13 nearly isotropic comets (NICs). The
  effective radii fall in the range 0.2-15 km for the ECs and 1.6-37
  km for the NICs. We note that several nuclei recently measured by the
  Hubble Space Telescope are subkilometer in radius, and that only 5 of
  the 65 well-measured EC nuclei have effective radii larger than 5 km. We
  estimate that the cumulative size distribution (CSD) of the ECs obeys a
  single power law with an exponent qS = 1.9 ± 0.3 down to a radius of
  ~1.6 km. Below this value there is an apparent deficiency of nuclei,
  possibly owing to observational bias and/or mass loss. When augmented
  by 21 near-Earth objects (NEOs) that are thought to be extinct ECs,
  the CSD flattens to qS = 1.6 ± 0.2. The cumulative size distribution
  of NICs remains ill-defined because of the limited statistical basis
  compared to ECs. The axial ratios a/b of the measured nuclei of ECs have
  a median value of ~1.5 and rarely exceed a value of 2, although it must
  be noted that the observed a/b values are often lower limits because
  of uncertainties in the aspect angle. The range of rotational periods
  extends from 5 to 70 h. The lower limit is significantly larger than
  that of main-belt asteroids and NEOs (~2.2 h, excluding the monolithic
  fast rotators), and this has implications for the bulk density of
  cometary nuclei. By combining rotation and shape data when available,
  we find a lower limit of 0.6 g cm-3 for the nucleus bulk density to
  ensure stability against centrifugal disruption. Cometary nuclei are
  very dark objects with globally averaged albedos falling within a
  very restricted range: 0.02-0.06, and possibly even narrower. (B-V),
  (V-R), and (R-I) color indices indicate that, on average, the color
  of cometary nuclei is redder than the color of the Sun. There is,
  however, a large diversity of colors, ranging from slightly blue to
  very red. While two comets have well-characterized phase functions with
  a slope of 0.04 mag deg-1, there is evidence for steeper (2P/Encke,
  48P/Johnson) and shallower (28P/Neujmin 1) functions, so that the
  observed range is 0.025-0.06 mag deg-1. The study of the physical
  properties of cometary nuclei is still in its infancy, with many
  unresolved issues, but significant progress is expected in the near
  future from current and new facilities, both groundbased and spaceborne.

---------------------------------------------------------
Title: Solar Cycle Variation of the Radiance and the Global Electronic
    Content of the Solar Corona
Authors: Lamy, P.; Llebaria, A.; Quemerais, E.
2004cosp...35.1876L    Altcode: 2004cosp.meet.1876L
  The question of the global activity of the solar corona, as a function
  of time and distance from the center of the Sun, is considered by
  analyzing SOHO/LASCO-C2 images over more than eight years, thus
  covering a large part of solar cycle 23. The polarized images are
  first analyzed to construct a photometric model of the F-corona wich
  reflects its annual variations resulting from geometric effects and
  of the instrumental straylight. Synoptic maps of the radiance of the
  K-corona are created at different distances between 2.7 and 6.5 solar
  radii. In order to conveniently quantify its temporal variation, the
  radiance is integrated first globally and then in zones of different
  latitudes to separate the equatorial and the polar regions. A similar
  analysis is performed with the electronic density obtained by the
  inversion of the polarized brightness assuming either a spherical or a
  cylindrical model of the corona. Both the radiance and the electronic
  density strongly vary with solar activity but the equatorial and polar
  regions exhibit different behaviours. These variations are compared
  with other indices of solar activity.

---------------------------------------------------------
Title: Dust Near The Sun
Authors: Mann, Ingrid; Kimura, Hiroshi; Biesecker, Douglas A.;
   Tsurutani, Bruce T.; Grün, Eberhard; McKibben, R. Bruce; Liou,
   Jer-Chyi; MacQueen, Robert M.; Mukai, Tadashi; Guhathakurta, Madhulika;
   Lamy, Philippe
2004SSRv..110..269M    Altcode:
  We review the current knowledge and understanding of dust in the inner
  solar system. The major sources of the dust population in the inner
  solar system are comets and asteroids, but the relative contributions
  of these sources are not quantified. The production processes inward
  from 1 AU are: Poynting-Robertson deceleration of particles outside of
  1 AU, fragmentation into dust due to particle-particle collisions,
  and direct dust production from comets. The loss processes are:
  dust collisional fragmentation, sublimation, radiation pressure
  acceleration, sputtering, and rotational bursting. These loss processes
  as well as dust surface processes release dust compounds in the
  ambient interplanetary medium. Between 1 and 0.1 AU the dust number
  densities and fluxes can be described by inward extrapolation of 1
  AU measurements, assuming radial dependences that describe particles
  in close to circular orbits. Observations have confirmed the general
  accuracy of these assumptions for regions within 30° latitude of the
  ecliptic plane. The dust densities are considerably lower above the
  solar poles but Lorentz forces can lift particles of sizes &lt; 5 μm
  to high latitudes and produce a random distribution of small grains
  that varies with the solar magnetic field. Also long-period comets
  are a source of out-of-ecliptic particles. Under present conditions
  no prominent dust ring exists near the Sun. We discuss the recent
  observations of sungrazing comets. Future in-situ experiments should
  measure the complex dynamics of small dust particles, identify the
  contribution of cometary dust to the inner-solar-system dust cloud, and
  determine dust interactions in the ambient interplanetary medium. The
  combination of in-situ dust measurements with particle and field
  measurements is recommended.

---------------------------------------------------------
Title: Properties of the nuclei of Centaurs Chiron and Chariklo
Authors: Groussin, O.; Lamy, P.; Jorda, L.
2004A&A...413.1163G    Altcode:
  We analyze visible, infrared, radio and spectroscopic observations of
  2060 Chiron in a synthetic way to determine the physical properties of
  its nucleus. From visible observations performed from 1969 to 2001,
  we determine an absolute V magnitude for the nucleus of 7.28±0.08
  with an amplitude of 0.16±0.03, implying a nearly spherical nucleus
  with a ratio of semi-axes a/b=1.16±0.03. Infrared observations at 25,
  60, 100 and 160 μm (i.e., covering the broad maximum of the spectral
  energy distribution) obtained with the Infrared Space Observatory
  Photometer (ISOPHOT) in June 1996 when Chiron was near its perihelion
  are analyzed with a thermal model which considers an intimate mixture
  of water ice and refractory materials and includes heat conduction
  into the interior of the nucleus. We find a very low thermal inertia
  of 3<SUP>+5</SUP><SUB>-3</SUB> J K<SUP>-1</SUP> m<SUP>-2</SUP>
  s<SUP>-1/2</SUP> and a radius of 71±5 km. Combining the visible and
  infrared observations, we derive a geometric albedo of 0.11±0.02. We
  find that the observed spectra of Chiron can be fitted by a mixture
  of water ice (∼30%) and refractory (∼ 70%) grains, and that this
  surface model has a geometric albedo consistent with the above value. We
  also analyze the visible, infrared and radio observations of Chariklo
  (1997 CU26) and derive a radius of 118±6 km, a geometric albedo
  of 0.07±0.01 and a thermal inertia of 0<SUP>+2</SUP><SUB>-0</SUB>
  J K<SUP>-1</SUP> m<SUP>-2</SUP> s<SUP>-1/2</SUP>. A mixture of water
  ice (∼ 20%) and refractory (∼ 80%) grains is compatible with the
  near-infrared spectrum and the above albedo.

---------------------------------------------------------
Title: Rotational Properties of Deep Impact Target Comet 9P/Tempel 1
Authors: Lisse, C. M.; Groussin, O.; A'Hearn, M. F.; Weaver, H. A.;
   Lamy, P.; Meech, K. J.; Belton, M. J. S.; Fernandez, Y. R.; Toth, I.
2004cosp...35.3161L    Altcode: 2004cosp.meet.3161L
  Comet 9P/Tempel 1 is the target of the Deep Impact mission to be
  launched at the end of this year. To improve our understanding of
  the rotational properties of the Tempel 1 nucleus [e.g., the current
  rotational period solutions are 22 and 42 hours with an axial ratio
  &gt; 2.5 :1 (Belton and Meech, 2004)], we performed 12 spectroscopic
  (7.5-40 microns) observations of the nucleus with the Spitzer Space
  Telescope over a 42 hour period in March 2004, and 18 photometric (F606)
  observations over a 42 hour period in May 2004 with the Hubble Space
  Telescope. Ground based optical observations of the lightcurve were
  also obtained during these times, in order to establish the albedo and
  inter-phase the results. We present here the lightcurve results, and
  the most likely solution for the rotational periodicity. We also discuss
  the axial ratio of the body as estimated from the lightcurve amplitudes.

---------------------------------------------------------
Title: Visible and thermal infrared observations of the nucleus of
    comet 67P/Churyumov-Gerasimenko
Authors: Lamy, P. L.; Jorda, L.; Toth, I.; Weaver, H. A.; Cruikshank,
   D.; Fernandez, Y.
2004cosp...35.1824L    Altcode: 2004cosp.meet.1824L
  The nucleus of comet 67P/Churyumov-Gerasimenko was first unambiguously
  detected in the visible with the planetary camera of the Hubble Space
  Telescope in early March 2003 (Lamy, P.L. et al., BAAS 35, 970). By
  observing the comet over 21 hours, the rotational period was found
  to be 12.3 hr and assuming an albedo of 0.04, a radius of 2 km was
  determined. It will be further observed in the thermal infrared with
  the Spitzer Space Telescope in late February 2004 at a heliocentric
  distance of 4.5 AU where it is presumed to be inactive. The nucleus will
  be imaged with the multiband imaging photometer (MIPS) at 24 microns
  seventeen times, over a time interval of 12.5 hr to as to cover the
  full light curve. The infared flux will give directly access to its
  size. By further combining with past HST observations, the rotational
  state of the nucleus will be better constrained and the albedo will
  be determined thus allowing to characterize its surface.

---------------------------------------------------------
Title: Approach to 3-D reconstruction of the solar corona from
    STEREO observations
Authors: Portier-Fozzani, F.; Lamy, P.; Llebaria, A.
2004cosp...35.3977P    Altcode: 2004cosp.meet.3977P
  In this poster, we present the work that we planned to do at the
  Laboratoire d'Astrophysique de Marseille concerning 3D reconstructions
  for the mission STEREO. Getting 3D informations from a large
  images database could be sometimes very puzzling while it requires
  3D inversions together with image analysis decomposition. From
  coronagraphic data, Vibert et al., 1997, used octree methods to
  rebuilt the neutral sheet of the solar corona. The octree method
  helps to reorganize a large number of data to be used by tomographic
  method. More recently, Portier-Fozzani and Inhester (SOLSPA 2001)
  proposed to reconstruct the solar corona in EUV by stereoscopic methods
  in using the solar cycle for improving the decomposition into structures
  to reconstruct. Portier-Fozzani, Bijaoui et al. (2002, 2004) used
  the Multiscale Vision Model based on spatial wavelets decomposition,
  to define in their image pair, groups of sub-objects, which are needed
  for the matching step in stereovision. We derive here how we can use
  these approaches for a full automatic reconstruction depending of the
  solar cycle.

---------------------------------------------------------
Title: Three-dimensional Model of the Streamer Belt over Solar
    Cycle 23
Authors: Saez, F.; Llebaria, A.; Lamy, P.
2004cosp...35.1854S    Altcode: 2004cosp.meet.1854S
  White-light images of the corona obtained with the SOHO/LASCO-C2
  coronagraph over more than 8 years reveal the dramatic changes
  of the structure and radiance distribution of the streamer belt
  from the minimum to the maximum of the present solar cycle. While
  it is qualitatively understood that the widening of the belt is
  a consequence of the tilting and warpening of the plasma current
  sheet, no quantitative study has been performed to derive physical
  parameters from these images. Our approach consists in reproducing the
  widening of the streamer belt and its periodic evolution with the solar
  rotation with a model combining a layer of plasma centered around the
  heliospheric current sheet and isolated streamers associated to active
  regions. We first determine the neutral sheet from solar photospheric
  magnetograms. Next, we introduce a parametric description of the
  electronic density in streamers and construct its octree representation
  based on a non-uniform sampling of the 3D space. The synthesized images
  are generated using a ray-tracing algorithm which calculates the
  Thomson scattering through the octree. Finally, we present a method
  that allows to simulate the time evolution of the coronal magnetic
  field during a Carrington rotation. The comparaison between the model
  and the LASCO-C2 observations is performed on synoptic maps, to offer
  a global view of the evolution of the corona, and on radiance profiles
  to assess the quantitative agreement.

---------------------------------------------------------
Title: The SIde-Looking Coronagraph (SILC) for the Solar Orbiter
    mission
Authors: Vives, S.; Lamy, P.; Korendyke, C.
2004cosp...35..951V    Altcode: 2004cosp.meet..951V
  The SIde-Looking Coronagraph (SILC) is one of the solar remote-sensing
  instruments proposed for the payload of the Solar Orbiter mission
  (European Space Agency, ESA). The Solar Orbiter will describe elliptic
  orbits with a large range of heliocentric distance, from 0.21 to
  0.6 AU, that is a factor 3 for the geometric conditions, and will
  reach heliographic latitudes as high as 38 degrees. Furthermore, the
  spacecraft will have offset pointing capability so as to target any
  point of the solar disk. These specificities (in addition to the severe
  thermal environment) are very restrictive for a coronagraph and lead
  us to propose an externally occulted coronagraph entirely protected
  from direct sunlight by remaining in the shadow of the spacecraft and
  looking sideways. The optical design follows the general principles
  of an externally-occulted coronagraph adapted to the side-looking
  concept. Although SILC loses the full spatial coverage of the corona,
  it can observe the inner part of the corona (down to 1.5 solar radii)
  during the whole mission and compensate the off-pointing of the
  spacecraft in the two directions. The performances, resulting from
  ray-tracing calculations, will be presented together with the first
  measurements of the stray light level.

---------------------------------------------------------
Title: Activity on the surface of the nucleus of comet 46P/Wirtanen
Authors: Groussin, O.; Lamy, P.
2003A&A...412..879G    Altcode:
  We present a thermal model of the nucleus of comet 46P/Wirtanen,
  constrained by the temporal variations of the water production rate,
  in order to understand the activity on its surface. We consider a
  spherical nucleus with a macroscopic mosaic of small and numerous
  active and inactive regions. At heliocentric distances r<SUB>h</SUB>
  &gt; 1.5 AU, the active regions represent 5-15% of the surface. At ~
  1.5 AU, a rapid increase takes place and the active fraction reaches
  70 to 100% in about 10 days, and then remains approximately constant up
  to perihelion where Q<SUB>H_2O</SUB>=1.3+/-0.3*E<SUP>28</SUP> molecule
  s<SUP>-1</SUP>. Post-perihelion, this fraction returns to ~ 10%. The
  model is consistent with a geometric albedo &lt;=0.06. A refractory
  crust likely forms post-perihelion and can explain the variations of
  the activity over an orbit. Finally, we derived an erosion of ~ 0.5
  m per revolution and a remaining lifetime for the nucleus of several
  hundred revolutions.

---------------------------------------------------------
Title: Long term evolution of cometary nuclei - Application to
    46P/Wirtanen
Authors: Groussin, O.; Lamy, P.; Valsecchi, G.; Gonczi, R.
2003DPS....35.3828G    Altcode: 2003BAAS...35Q1488G
  We present a new method to study the long term evolution of cometary
  nuclei in order to retrieve their original size. We consider first the
  case of comet 46P/Wirtanen (the former target of the Rosetta mission)
  and we calculate the past evolution of its orbital elements over
  10<SUP>5</SUP> years, with and without non-gravitational forces. The
  chaotic behaviour is simulated by considering 9 different values of
  the initial mean anomaly. For an homogeneous nucleus with a composition
  of 50% water ice + 50% dust and a density of 500 kg/m<SUP>3</SUP>, we
  obtain an initial radius in the range 1.4-7.8 km, depending upon the
  inital conditions. This result also depends upon the composition and
  the density, but not on the presence, or not, of the non-gravitational
  forces. We will apply this method to many other cometary nuclei in
  the future.

---------------------------------------------------------
Title: LASCO C2 and C3 Level-1 Images: Calibration and Pipeline
    Processing
Authors: Thernisien, A. F.; Morrill, J.; Llebaria, A.; Rich, N.;
   Vourlidas, A.; Esfandiari, E.; Wang, D.; Korendyke, C.; Moses, D.;
   Biesecker, D.; Bout, M.; Lamy, P.; Howard, R. A.
2003AGUFMSH41B0461T    Altcode:
  The LASCO C2 and C3 coronagraphs have provided coronal observations
  since May, 1996. Initial calibrations have been available during most
  of this time period. We have subsequently completed a re-evaluation
  and refinement of these calibration procedures. We are now able
  to present the final version of the level-1 data using the latest
  improvements from in-flight calibration results. Further details
  on the LASCO calibration and level-1 data access are presented at
  http://lasco-www.nrl.navy.mil/level_1/lascocal_index.html. In this
  presentation we will sum up the different aspects of the LASCO
  C2-C3 image corrections such as vignetting, absolute photometry,
  time corrections, geometric distortion, sun center position, and
  spacecraft orientation.

---------------------------------------------------------
Title: New spin period determination for comet 6P/d'Arrest
Authors: Gutiérrez, P. J.; de León, J.; Jorda, L.; Licandro, J.;
   Lara, L. M.; Lamy, P.
2003A&A...407L..37G    Altcode:
  A lightcurve of comet 6P/d'Arrest from R-band CCD images taken at
  La Palma 2.52 m NOT telescope is presented. The lightcurve shows
  noticeable periodic changes in brightness produced by rotational
  modulation. The periodogram analysis of the lightcurve shows a peak with
  a confidence level exceeding 99.9% at 3.336 h. Assuming an elongated
  nucleus, the most likely spin period is therefore 6.67 +/- 0.03 h,
  but other periodicities are also possible. The peak to peak amplitude
  is 0.082 +/- 0.016 mag. This period, and the other peaks detected in
  the periodogram, are not commensurable with previous estimates of the
  spin period of comet 6P/d'Arrest. If all the measurements are correct,
  the differences between this estimate and the previous ones could be
  due to a possible change in the spin period of comet 6P/d'Arrest or
  to this comet being rotating in a complex mode.

---------------------------------------------------------
Title: Outgassing-induced effects in the rotational state of comet
    67P/Churyumov-Gerasimenko during the Rosetta mission.
Authors: Gutierrez, P. J.; Jorda, L.; Samarasinha, N. H.; Lamy, P.
2003DPS....35.3802G    Altcode: 2003BAAS...35..984G
  Comet 67P/Churyumov-Gerasimenko [hereafter 67P/C-G] is the new main
  target of the Rosetta mission (a cornerstone mission in ESA's "Horizon
  2000" program). The Rosetta spacecraft will orbit comet 67P/C-G for
  almost one year in 2015, and a module will land on its surface. In order
  to ensure the correct interpretation of the measurements taken by the
  instruments onboard the spacecraft and to help in the definition of
  an appropriate landing strategy, we carry out numerical simulations of
  the evolution of the rotational state of this comet under the effects
  of the sublimation-induced torque from the currrent epoch to the end of
  the Rosetta mission. In the simulations, we will take into account the
  known observational constraints on the nucleus size and the spin period
  and consider a range of scenarios: two thermophysical models, several
  densities, three initial angular momentum orientations, several activity
  patterns on the surface, and two initial rotational states. We will
  present our initial results including the typical changes in the angular
  momentum orientation and the spin period during the operational phase.

---------------------------------------------------------
Title: SOHO/LASCO observation of an outburst of Comet 2P/Encke at
    its 2000 perihelion passage
Authors: Lamy, P.; Biesecker, D. A.; Groussin, O.
2003Icar..163..142L    Altcode:
  Comet 2P/Encke was observed with the SOHO/LASCO C2 and C3 coronagraphs
  over a time interval of 11 days, starting 4 days before its September
  2000 perihelion passage and through several broadband visible
  filters. The lightcurve reveals an outburst which started 4.9 days
  after perihelion, with the brightness of the coma increasing by 1.5
  mag in just a few hours and progressively decreasing thereafter,
  probably going back to its original state in about 9 days. The color
  information indicates that an approximately solar color continuum was
  detected, implying that the observed signals were dominated by solar
  light scattered off submillimetric dust grains. We propose that the
  rapid migration of the subsolar point over the southern hemisphere
  during the perihelion passage activates one or several new active
  regions enriched in submillimetric grains, with the observed outburst
  corresponding to the initial blow-off of their mantle. This scenario
  is consistent with other observations and implies that the south polar
  region of the nucleus of 2P/Encke has very distinct properties.

---------------------------------------------------------
Title: New Modeling of Cometary Dust Tails
Authors: Jorda, L.; Lamy, P. L.; Coliac, J. -F.; Bout, M.; Colas,
   F.; Lecacheux, J.; Rauer, H.; Weiler, M.
2003DPS....35.3820J    Altcode: 2003BAAS...35R.988J
  We present a technique for modeling cometary dust tails. The
  technique is based on Monte Carlo simulations of a large number of
  “model-images”, recombined linearly to fit the observed CCD image of
  the dust tail. In essence, our technique is similar (but not identical)
  to that originally proposed by Kimura and Liu (1975, 1982) and developed
  by Fulle (1987, 1989), but incorporates new features such as the
  rigorous calculation of the light scattered by the dust grains. It
  can be used to interactively retrieve the dust size and velocity
  distributions and to compute the dust production rate. We present
  the application of this technique to comet 67P/Churyumov-Gerasimenko,
  the new target of ESA's Rosetta mission and to comets observed with
  the SOHO/LASCO coronagraphs (C/1996 B2 Hyakutake, C/2002 S2 SOHO 517,
  C2002 X5 Kudo-Fujikawa, C2002 V1 NEAT and 96P/Machholz 1). <P />--
  Fulle, M., A&amp;A 171, 327, 1987. <P />-- Fulle, M., A&amp;A 217, 283,
  1989. <P />-- Kimura, H., and Liu, C.-P., AcASn 16, 138, 1975. <P />--
  Kimura, H., and Liu, C.-P., AcASn 23, 232, 1982.

---------------------------------------------------------
Title: The Nucleus of Comet 67P/Churyumov-Gerasimenko, the New Target
    of the Rosetta Mission
Authors: Lamy, P. L.; Toth, I.; Weaver, H.; Jorda, L.; Kaasalainen, M.
2003DPS....35.3004L    Altcode: 2003BAAS...35..970L
  We report the detection of the nucleus of comet
  67P/Churyumov-Gerasimenko, the new target of the Rosetta mission, with
  the Planetary Camera (WFPC2) of the Hubble Space Telescope (HST). The
  observations were performed between 11.4 and 12.3 March 2003 (i.e.,
  a time interval of 21 hr) when the comet was at heliocentric and
  geocentric distances of respectively 2.51 and 1.53 AU and at a phase
  angle of 4.8 deg. The high spatial resolution (a WFPC2 pixel projected
  to 50 km at the distance of the comet) insured a very large contrast of
  the nucleus over its surrounding coma, reaching a factor of typically
  30 in the peak pixels. The 61 images allowed us to determine 49 R
  magnitudes and 12 V magnitudes of the nucleus. Assuming a spherical
  body with a geometric albedo of 0.04 and a phase coefficient of 0.04
  mag/deg, we derived an effective radius of 1.98 +/- 0.02 km. The
  lightcurve data were analyzed using both the PDM (Phase Dispersion
  Minimization) and the Fourier technics. Assuming a classical double
  peak lightcurve, the two technics give the same rotational period of
  P=12.3 +/- 0.27 hr. This result is highly robust since the probability
  that the period detection with the PDM technics is due to random noise
  amounts to only 3E-11. The lightcurve which conspicuously deviates
  from a sinusoide with shallow minima and narrow, unequal maxima, was
  inverted in order to model the 3-dimensional shape of the nucleus using
  the method developed by Kaasalainen et al. (Icarus 153, 37, 2001). The
  rotational state is constrained to be close to principal axis rotation
  of maximum inertia to get physically consistent solutions. All plausible
  solutions share the same qualitative global shape characteristics. The
  model which best fits the observed lightcurve (rms deviation of 0.028
  mag) has a rotation axis tilted by about 8 deg from the principal axis,
  a rotational period of 12.69 +/-0.10 hr, an aspect angle of 90 +/- 20
  deg (i.e., equatorial view) and a slightly rugged shape. The color of
  the nucleus is moderately red with a color index V-R = 0.51, the most
  common value among cometary nuclei. The OH production rates impose a
  rather low active fraction at perihelion, 4% to 7%. The activity is
  thus limited to probably a few, very small areas, consistent with the
  detection of several jets in the coma. The dust production rate was
  characterized by Afρ = 40 cm. <P />We thank S. Beckwith for granting
  us HST Director's Discretionary time on a very short notice. This work
  was supported by grants from CNRS and CNES, and from NASA to H. W.

---------------------------------------------------------
Title: Hubble Space Telescope Observations of the Nucleus Fragment
    73P/Schwassmann-Wachmann 3-B
Authors: Toth, I.; Lamy, P. L.; Weaver, H. A.
2003DPS....35.3805T    Altcode: 2003BAAS...35..985T
  The nucleus of 73P/Schwassmann-Wachmann 3 (73P/SW3), a Jupiter-Family
  comet, has non-tidally broken into at least three components A, B and
  C, in autumn 1995. Fragment B was detected with the Planetary Camera
  2 of the Hubble Space Telescope on 26 November 2001. i.e., after the
  comet's perihelion passage on 27.9 January 2001, when it was at 3.25
  AU from the Sun, 2.33 AU from the Earth, and at a solar phase angle
  of 7.4<SUP>o</SUP>. The high spatial resolution of the PC2 allowed
  to separate the signal of the faint nucleus fragment from that of its
  active coma, and we measured its R magnitude from our images taken with
  the F675W filter. Assuming a spherical body whose geometric albedo is
  0.04 and a linear phase coefficient of 0.04 mag/deg for the R band,
  we derived an effective radius of 0.68+/-0.04 km. The short time span
  of our HST observations did not allow to determine its shape but the
  lower limit of its axial ratio a/b (assuming a prolate spheroid)
  is ∼1.16. From the pre-breakup radius of the original nucleus
  of 1.3 km determined by Boehnhardt et al. (2002: EMPl 90, 131),
  we found that the fractional volume of fragment B is about 14%. Its
  size of a few hundred meters, typical of fragments of other split
  comets, is probably too large for a primordial building block and
  indicate that it still is a conglomerate; further disintegration of
  this fragment remains possible. Its level of activity is remarkably
  high in spite of a heliocentric distance of ∼3.2 AU, just beyond
  the limit for sublimation of water ice (2.8 AU). We measured an Afρ
  of 19.6-23.2 cm but the determination of a dust production rate is
  precluded by the absence of gas production rates at the time of our
  observation. Ground-based observations performed in 2001 by Boehnhardt
  et al. (2002: EMPl 90, 131) indicate that another fragment (E) has
  already disappeared, and we conclude that this may well be short-term
  fate of fragment B as it may not survive its next perihelion passage in
  2006. The tau-Herculids meteor swarm associated to 73P/SW3 will likely
  experience an increase of activity. <P />This work was supported by the
  CNRS, CNES, and Université de Provence, France, and by the Hungarian
  Academy of Science through grant No. 9871.

---------------------------------------------------------
Title: SOHO/LASCO Observation of Comet C/2002 X5 Kudo-Fujikawa at
    its 2003 Perihelion Passage
Authors: Bout, M. V.; Lamy, P. L.; Llebaria, A.
2003DPS....35.3821B    Altcode: 2003BAAS...35..988B
  Comet C/2002 X5 Kudo-Fujikawa was observed with the SOHO/LASCO C2
  and C3 coronagraphs over a time interval of 7 days, starting 4 days
  before its 29 January 2003 perihelion passage and through several
  broadband visible filters. A total of 134 images were obtained with
  the C3 clear filter, 51 images with the C2 orange filter completed
  by 20 color sequences. The lightcurves reveal that the brightness
  of the coma steeply increased to reach local maxima on 27 January,
  then suffered a drastic turnover, decreasing by about 0.8 mag to reach
  minimum values on 27.8, then increased again to reach absolute maxima
  slightly before perihelion passage and finally decreased. This pattern
  of activity is consistent with the apparition of a new, anti-solar dust
  tail widely separated from the main tail that the comet originally
  sported. This translates in an unusual butterfly pattern where two
  "decoupled" tails co-exist at the same time. Short-time variations
  in the lightcurves may be caused by the rotation of the nucleus,
  suggesting a rotation period of about 4 hours.

---------------------------------------------------------
Title: The solar high-resolution imager - coronagraph LYOT mission
Authors: Vial, Jean-Claude; Song, Xueyan; Lemaire, Philippe; Gabriel,
   Alan H.; Delaboudiniere, Jean-Pierre; Bocchialini, Karine; Koutchmy,
   Serge L.; Lamy, Philippe L.; Mercier, Raymond; Ravet, Marie Francoise;
   Auchere, Frederic
2003SPIE.4853..479V    Altcode:
  The LYOT (LYman Orbiting Telescope) solar mission is proposed to
  be implemented on a micro-satellite of CNES (France) under phase A
  study. It includes two main instruments, which image the solar disk
  and the low corona up to 2.5 R<SUB>o</SUB> in the H I Lyman-α line
  at 121.6 nm. The spatial resolution is about 1” for the disk and
  2.5” for corona. It also carries an EIT-type telescope in the He II
  (30.4 nm) line. The coronagraph needs a super polished mirror at the
  entrance pupil to minimize the light scattering. Gratings and optical
  filters are used to select the Lyman-α wavelength. VUV cameras with
  2048×2048 pixels record solar images up to every 10 seconds. The
  satellite operates at a high telemetry rate (more then 100 kb/s,
  after onboard data compression). The envisaged orbits are either
  geostationary or heliosynchronous. Possible launch dates could be end
  of 2006 - beginning of 2007.

---------------------------------------------------------
Title: Commission 21: Light of the night sky (Lumière du ciel
    nocturne)
Authors: Lamy, Philippe
2003IAUTA..25..199L    Altcode: 2003IAUTr..25A.199L
  No abstract at ADS

---------------------------------------------------------
Title: Two-dimensional electron density in the solar corona from
    inversion of white light images - Application to SOHO/LASCO-C2
    observations
Authors: Quémerais, E.; Lamy, P.
2002A&A...393..295Q    Altcode:
  We present here the inversion method which has been developed to derive
  the electron density in the Solar Corona from LASCO-C2 white light
  images. We discuss how our inversion scheme can be applied either
  to images of polarized brightness of the corona or images of total
  brightness after removal of the dust and stray light components. The
  outputs from both schemes are compared. For the inversion of
  two-dimensional images of the solar corona, it is necessary to assume a
  global geometry for the electron density. We compare results obtained
  for spherical and axi-symmetric geometries. Finally, our results for
  December 1996 are compared to previous derivations of the electron
  radial density profiles obtained by other measurements.

---------------------------------------------------------
Title: The Study of Comets
Authors: Combi, M. R.; Capria, M. T.; Cremonese, G.; de Sanctis,
   M. C.; Farnham, T. L.; Fernandez, Y. R.; Festou, M. C.; Fink, U.;
   Green, J. R.; Harris, W. M.; Hergenrother, C. W.; Lamy, P. L.;
   Larson, S. M.; Levison, H. F.; Lien, D. J.; Lisse, C. M.; Meisel,
   D. D.; Moehlmann, D. T. F.; Mueller, B. E. A.; Samarasinha, N. H.;
   Sitko, M. L.; Weaver, H. A.; Weissman, P. R.
2002ASPC..272..323C    Altcode: 2002fsse.conf..323C
  The study of comets is critical to our understanding the origin,
  structure and evolution of the solar system in general and of life
  itself. We present here a brief summary of our current understanding
  of comets and their important place in the solar system, as well as
  our recommendations regarding priorities for their study over the next
  decade in the context of a coordinated program of spacecraft missions
  and ground-based and theoretical investigations.

---------------------------------------------------------
Title: Sungrazing Comets Discovered with the SOHO/LASCO Coronagraphs
    1996-1998
Authors: Biesecker, D. A.; Lamy, P.; St. Cyr, O. C.; Llebaria, A.;
   Howard, R. A.
2002Icar..157..323B    Altcode:
  The Kreutz sungrazing family of comets is unique because of its small
  perihelion distance and because of the large number of known members
  of this family. SOHO/LASCO coronagraph observations beginning in 1996
  have revealed an unprecedented number of Kreutz comets. These new
  coronagraph observations improve upon earlier observations because of a
  larger field-of-view, increased image cadence, and better photometric
  measurements. This paper presents the lightcurves of the 141 Kreutz
  family comets observed from 1996 through 1998. Throughout this period,
  the number of family members discovered each year is shown to be
  constant. None of the comets were detected postperihelion. The
  lightcurves show distinctive characteristics which reveal much
  about the properties of the nuclei. It is shown that the individual
  fragments can be related to one of two “standard candles,” which
  we call Universal Curves. The comets all reach a peak brightness at
  one of two characteristic distances (both near 12 R<SUB>⊙</SUB>)
  and that the comets fragment at another characteristic distance
  (about 7 R<SUB>⊙</SUB>). Also, evidence is seen for line emission,
  which varies with heliocentric distance.

---------------------------------------------------------
Title: The fractal nature of the polar plumes
Authors: Llebaria, A.; Saez, F.; Lamy, P.
2002ESASP.508..391L    Altcode: 2002soho...11..391L
  Polar plumes are often perceived as isolated structures, possibly
  tube-like, in super-radial expansion. As a consequence, coronal
  holes are considered composed of plumes and dominating inter-plume
  regions from which the fast solar wind originates. In order to test
  the validity of this concept, we pursued the analysis of a sequence of
  high cadence continuous observations obtained with the SOHO/LASCO-C2
  coronagraph in March 1997. The spectral analysis of the plume pattern
  show that their spatial distribution is of fractal type. This implies
  that their distribution in a surface section of the coronal hole is
  self-affine and that coronal holes have a fibrous structure, at least
  at the spatial scales of the visible observations.

---------------------------------------------------------
Title: Electron density in coronal jets
Authors: Bout, M.; Lamy, P.; Llebaria, A.
2002ESASP.508..379B    Altcode: 2002soho...11..379B
  Coronal jets are observed by the SOHO/LASCO C2 and C3 coronagraphs
  as thin, highly collimated structures. The determination of their
  electron density cannot be performed with the standard inversion of pB
  images because of the inherent assumption of global spherical or axial
  symmetry of the corona which is totally inappropriate in the case of
  local structures. Our analysis first isolates the jets by subtracting
  the background corona. Their radiance is then compared to calculated
  models which assume a tube like structure. This allows to derive the
  true radial profile of their electron density.

---------------------------------------------------------
Title: Calibration of the LASCO C3 Coronal Images
Authors: Morrill, J.; Biesecker, D.; Esfandiari, A.; Korendyke, C.;
   Moses, D.; Rich, N.; Vourlidas, A.; Wang, D.; Howard, R. A.; Lamy,
   P.; Llebaria, A.; Thernisien, A.
2002AAS...200.5503M    Altcode: 2002BAAS...34R.732M
  The LASCO C3 coronagraph has provided coronal observations since May,
  1996. Preliminary calibrations have been available during most of this
  time period. However, some aspects of the calibration have required
  re-evaluation and we are just completing a complete review of the
  calibration procedure for these images. In this presentation we will
  discuss the steps required to correct LASCO C3 images. This includes
  corrections required by both optical and electrical characteristics
  of the instrument as well as timimg and spacecraft pointing driven
  correctons.

---------------------------------------------------------
Title: The Nucleus of Comet 22P/Kopff and Its Inner Coma
Authors: Lamy, P. L.; Toth, I.; Jorda, L.; Groussin, O.; A'Hearn,
   M. F.; Weaver, H. A.
2002Icar..156..442L    Altcode:
  We report the detection of the nucleus of Comet 22P/Kopff with the
  Planetary Camera of the Hubble Space Telescope (HST) and with the
  Infrared Camera of the Infrared Space Observatory (ISOCAM). The
  HST observations were performed on 18 July 1996, 16 days after its
  perihelion passage of 2 July 1996, when it was at R<SUB>h</SUB>=1.59
  AU from the Sun and Δ=0.57 AU from the Earth. A sequence of images
  taken with four broad-band filters was repeated eight times over
  a 12-h time interval. The ISOCAM observations were performed on 15
  October 1996, 106 days after the perihelion passage, when the comet
  was at R<SUB>h</SUB>=1.89 AU from the Sun and Δ=1.32 AU from the
  Earth. Seven images were obtained with a broad-band filter centered at
  11.5 μm. In both instances, the spatial resolution was appropriate to
  separate the signal of the nucleus from that of the coma. We determine
  the Johnson-Kron-Cousins BVRI magnitudes of the nucleus. The visible
  lightcurves constrain neither the rotation period nor the ratio
  of semiaxes. We favor the solution of a rather spherical nucleus,
  although the situation of a pole-on view of an irregular body cannot
  be excluded. The systematic decreasing trend of the lightcurves
  could suggest a period of several days. Combining the visible and
  infrared observations, we find that an ice-dust mixed model is ruled
  out, while the standard thermal model leads to a nuclear radius of
  R<SUB>n</SUB>=1.67±0.18 km of albedo p<SUB>v</SUB>=0.042±0.006. The
  red color of the nucleus is characterized by a nearly constant gradient
  of S'=14±5% per kÅ from 400 to 800 nm. We estimate a fractional
  active area of 0.35 which places 22P/Kopff in the class of highly
  active short-period comets. At R<SUB>h</SUB>=1.59 AU, the dust coma
  is characterized by a red color with a reflectivity gradient S'=17±3%
  per kÅ, compatible with that of the nucleus, and Afρ=545 cm, yielding
  a dust production rate of Q<SUB>d</SUB>=130 kg sec <SUP>-1</SUP>.

---------------------------------------------------------
Title: New insights on the onsets of coronal mass ejections from soho
Authors: Plunkett, S. P.; Michels, D. J.; Howard, R. A.; Brueckner,
   G. E.; St. Cyr, O. C.; Thompson, B. J.; Simnett, G. M.; Schwenn, R.;
   Lamy, P.
2002AdSpR..29.1473P    Altcode:
  Coronal mass ejections (CMES) are among the most dramatic forms of
  transient activity occurring in the solar atmosphere. Despite over
  twenty years of research, many basic questions related to the physics
  of CMEs have remained unanswered. Observations with the LASCO and EIT
  experiments on SOHO, combined with recent theoretical modeling, have
  provided new insights on some of these outstanding questions and have
  also raised many new ones that need to be addressed in the future. In
  this paper, we present some of the new results from SOHO pertaining
  to the source regions and onsets of CMEs, and their evolution in the
  corona. We emphasize the important role that studies of CMEs will play
  in the International Solar Cycle Studies program.

---------------------------------------------------------
Title: New Modeling of 19P/Borrelly s Spin State
Authors: Jorda, L.; Gutierrez, P.; Lamy, P.
2002cosp...34E3221J    Altcode: 2002cosp.meetE3221J
  Comet 19P/Borrelly has been imaged by the Deep Space 1 (DS1) spacecraft
  in Sept. 2001. The images allowed the retrieval of the size and shape
  of the comet nucleus with a high accuracy. The spin orientation of
  this comet has also been derived from the DS1 MICAS images and from
  ground-based observations obtained during the last decades. We will
  present here new modeling of the temporal evolution of the spin state
  of comet 19P/Borrelly using these new observational constraints.

---------------------------------------------------------
Title: Solar cycle variation of the radiance and the global electron
    density of the solar corona
Authors: Lamy, P.; Llebaria, A.; Quemerais, E.
2002AdSpR..29..373L    Altcode:
  The question of the global activity of the solar corona, as a function
  of time and distance from the center of the Sun, is considered by
  analyzing SOHO/LASCO-C2 daily polarized images over four years, i.e.,
  from the minimum to the rising phase of the 23rd solar cycle. After
  proper correction for instrumental polarization, they are combined
  to produce maps of the polarized radiance pB and of the radiance
  of the K-corona (assuming a model for the K-corona polarization
  p <SUB>K</SUB>). The electron density is obtained by inversion of
  the pB images assuming local spherical symmetry. Synoptic maps are
  created at four distances between 2.7 and 5.5 solar radii. In order to
  conveniently quantify their temporal variation, the polarized radiance,
  the radiance and the electron density are integrated first globally
  and then in zones of different latitudes to separate the equatorial and
  the polar regions. These integrals remained constant in 1996 and then
  progressively increased with the rising activity of the Sun. However
  the polar and equatorial regions exhibited different behaviours as the
  former remained stable over a much longer time interval and experienced
  a larger increase than the latter.

---------------------------------------------------------
Title: Characterization of coronal streamers from LASCO-C2
    observations and implications for the slow solar wind
Authors: Lamy, P.; Bout, M.; Llebaria, A.; Thernisien, A.
2002cosp...34E1507L    Altcode: 2002cosp.meetE1507L
  Recent analysis of LASCO images of the corona obtained during the
  rising phase of the present solar cycle indicates that there exists
  streamers distinct from the classical streamer belt which results
  from line-of-sight integration through folds in a warped current sheet
  (Liewer et al., 2001, JGR 106, A8, 15903). These "isolated" streamers
  are the result of scattering from regions of enhanced density associated
  with active region outflow. A preliminary quantitative analysis
  of LASCO-C2 images of several such structures indicates enhancement
  factors as large as 50 compared to the classical model of Van de Hulst
  (Bout et al., 2002, SOHO-11 Conference). We will report on further
  progress in analyzing these streamers and our attempt to measure
  outflow speeds. Our ultimate purpose is to assess the contribution of
  these structures to the slow solar wind.

---------------------------------------------------------
Title: The Properties of Sun-grazing Comets
Authors: Lamy, P.; Biesecker, D.
2002cosp...34E3159L    Altcode: 2002cosp.meetE3159L
  Over 450 sun -grazing comets have now been detected with the Large
  Angle Spectroscopic Coronagraphs (LASCO) on the Solar and Heliospheric
  Observatory (SOHO). The bulk of them belong to the Kreutz family while
  49 are either scattered or belong to other families. In this review,
  we first consider the statistical properties of the distribution of
  the orbital elements to establish the reality of sub-groups and to
  characterize the process of their fragmentation. We then analyze the
  light curves and confront the different observed behavior with the
  dynamical families. For a few comets, color information is available
  and helps to characterize the sun-grazers.

---------------------------------------------------------
Title: Characterization of the polar plumes from high cadence
    LASCO-C2 observations
Authors: Llebaria, A.; Thernisien, A.; Lamy, P.
2002AdSpR..29..343L    Altcode:
  In order to understand the spatio-temporal characteristics of polar
  plumes, we analyzed a sequence of continuous observations obtained
  with the SOHO/LASCO-C2 coronagraph over a period of 3 days with a time
  resolution of 10 minutes. We generated the time intensity diagram (TID)
  where the radiance of the plumes is displayed as a function of their
  angular positions and time. The derivatives of the TID with respect
  to the phase angle on the one hand and to time on the other hand allow
  us to define the trajectories of individual plumes and their temporal
  variations. This confirms that polar plumes are enduring structures
  that are only transiently lit, as we found before, but the present
  analysis reveals that the blinking takes place on time scales as
  short as 2 hours. This is confirmed by the radial intensity diagrams
  (RID) which track each individual plume by displaying its radiance
  as a function of time and distance. These diagrams also indicate a
  constant speed of expansion with a mean value of 460 km/sec.

---------------------------------------------------------
Title: Properties of the surface of 46P/Wirtanen from the observed
    water production rate
Authors: Groussin, O.; Lamy, P.
2002cosp...34E2963G    Altcode: 2002cosp.meetE2963G
  We present a thermal model to explain the temporal variations of
  the water production rates QH2 O of comet 46P/Wirtanen, in order to
  analyse its surface. Our model is a differenciated spherical nucleus
  with a macroscopic mosaic of small and numerous active and inactive
  regions. At a heliocentric distance Rh &gt;1.5 AU, the active regions
  represent 5-15 % of the surface. At 1.5 AU, a rapid increase takes
  place in about 10 days and the active fraction reaches 70 to 100 %,
  and then remains approximatively constant up to perihelion where QH2 O
  =1.1-1.7 1028 molecules s-1 . Post-perihelion, the activity goes down
  again to 10 %. The model is consistent with a geometric albedo lower
  than 0.1. A rubble mantle of a few millimeters can form post-perihelion
  and explain the variations of the activity over one orbit. Finally,
  we derived an erosion of 1 meter per revolution and a lifetime for
  the nucleus of several hundred revolu- tions.

---------------------------------------------------------
Title: The Rosetta/Osiris Narrow Angle Camera: Performances and
    Prospects for High Spatial Resolution Imaging of the Nucleus of
    Comet 46P/Wirtanen
Authors: Lamy, P.; Jorda, L.; Origne, A.; Thomas, N.; Hviid, S.
2002cosp...34E3158L    Altcode: 2002cosp.meetE3158L
  The Narrow Angle Camera (NAC) of the OSIRIS experiment is aimed at
  imaging a cometary nucleus, that of 46P/Wirtanen, at an unsurpassed
  spatial resolution of a few centimeters per pixel. We describe the
  innovative three-mirror, anastigmatic optical design and its all
  silicon carbide implementation (mirrors and structure). We report
  on the extended program of tests and calibrations carried out to
  fully characterize the instrument, in particular at low temperatures,
  and synthesize the actual performances. We finally discuss the future
  program of observation and the prospect for characterizing the asteroids
  Otawara and Siwa and the nucleus of 46P/Wirtanen.

---------------------------------------------------------
Title: Evolution of the Electron Density in the Streamer Belt during
    the Solar
Authors: Llebaria, A.; Lamy, P.; Saez, F.
2002cosp...34E1606L    Altcode: 2002cosp.meetE1606L
  White-light images of the corona obtained with the SOHO/LASCO-C2
  coronagraph over more than six years reveal the dramatic changes
  of the structure and radiance distribution of the streamer belt
  from the minimum to the maximum of the present solar cycle. While
  it is qualitatively understood that the widening of the belt is a
  consequence of the tilting and warpening of the plasma current sheet,
  no quantitative study has been performed to derive physical parameters
  from these images in order to help characterizing the slow solar
  wind. Our approach consists in reproducing the widening of the streamer
  belt and its periodic evolution with the solar rotation with a model
  combining a layer of plasma centered around the heliospheric current
  sheet and isolated streamers associated to active regions. The Thompson
  scattering from the coronal electrons of this 3D model is calculated
  and comp ared to the LASC0-C2 images. This allows to estimate the local
  electron density in the corona between 3 and 6 solar radii during the
  rising phase of a solar cycle and to put constraints on the evolution
  of the slow solar wind.

---------------------------------------------------------
Title: Hubble Space Telescope Observations of the Nucleus of Comet
    9P/Tempel 1
Authors: Lamy, P. L.; Toth, I.; A'Hearn, M. F.; Weaver, H. A.;
   Weissman, P. R.
2001Icar..154..337L    Altcode:
  The nucleus of Comet 9P/Tempel 1, the target of the Deep Impact mission,
  was detected during Hubble Space Telescope observations taken with
  the wide-field planetary camera 2 (WFPC2) on 31 December 1997 when
  the comet's solar phase angle was 3.°8, its heliocentric distance was
  4.48 AU, and its geocentric distance was 3.53 AU. Sixteen images were
  taken through the F675W filter, and all of them revealed a point-like
  source without any detectable coma. From these images, we derived the
  R magnitude of the nucleus in the Johnson-Kron-Cousins photometric
  system for the entire 11.5-h time span of the observations. Assuming
  a prolate spheroid whose spin axis lies close to the plane of the
  sky, the partial lightcurve indicates semi-axes a=3.9 km and b=2.8
  km (assuming a geometric albedo of 0.04 for the R band and a phase
  coefficient of 0.04 mag deg <SUP>-1</SUP>) and a rotational period
  in the range of ∼25-33 h. The upper limit of the parameter Afρ,
  which characterizes the dust production rate, is 1 cm. We also derive
  a fractional active area at 1.78 AU of ∼4%.

---------------------------------------------------------
Title: Latest Results from SOHO/LASCO Observations of Kreutz Family
    Comets
Authors: Biesecker, D. A.; Lamy, P. L.; St. Cyr, O. C.; Llebaria,
   A.; Howard, R. A.
2001DPS....33.4601B    Altcode: 2001BAAS...33Q1123B
  As of September 2001, almost 350 members of the Kreutz sungrazing comet
  family have been observed with the LASCO coronagraphs on SOHO. The
  lightcurves of many of these comets share common features. They
  all reach a peak brightness at a heliocentric distance of about 12
  solar radii (0.056 AU), then fade as they approach closer to the Sun,
  down to a distance of 7 solar radii where the fading stops. A closer
  examination reveals that two groups can be distinguished, one which
  peaks at 11.2 solar radii and one at 12.3 solar radii. Observations
  through an `Orange' filter (5400-6400 Angstroms) are systematically
  brighter than those through a `Clear' filter (4000-9000 Angstroms)
  and the difference changes with heliocentric distance. Recently,
  high cadence observations with other color filters have shown that the
  enhancement is limited to the Orange and Clear filters. This supports
  our idea that Na emission is a likely candidate for the enhancement. We
  will present these observations as well as our latest ideas to explain
  the LASCO observations.

---------------------------------------------------------
Title: The Nucleus of 10 Short-Period Comets
Authors: Lamy, P. L.; Toth, I.; Weaver, H. A.; Delahodde, C. E.;
   Jorda, L.; A'Hearn, M. F.
2001DPS....33.3101L    Altcode: 2001BAAS...33Q1093L
  We report on the successful detection and extensive characterization
  of the nuclei of 10 short-period comets with the Hubble Space
  Telescope: 47P/Ashbrook-Jackson, 61P/Shajn-Schaldach, 70P/Kojima,
  74P/Smirnova-Chernikh, 76P/West-Kohoutek-Ikemura, 82P/Gehrels 3,
  86P/Wild 3, 87P/Bus, 110P/Hartley 3, 147P/Kushida-Muramatsu. The
  observations were performed with the Planetary Camera of WFPC2 during
  cycle 9, between July 2000 and June 2001. Each comet was observed eight
  times over a time span of about 12 hours through different filters, up
  to three (V, R, I) for the brightest ones. The sizes were determined
  assuming a geometric albedo of 0.04 for the R band and a phase law
  of 0.04 mag/deg. We confirm our past findings that cometary nuclei
  are generally extremely small; the radius of 147P/Kushida-Muramatsu
  was only 0.13 km. We also present the results for the colors and
  the lightcurves of the nuclei and discuss the implications for
  their shape and rotational state. This work was supported by grants
  from the Universite de Provence, from C.N.E.S., C.N.R.S. (France),
  from the Hungarian Academy of Science and from NASA through grant
  HST-GO-08699.01-A from the STScI.

---------------------------------------------------------
Title: Broadband infrared photometry of comet Hale-Bopp with ISOPHOT
Authors: Grün, E.; Hanner, M. S.; Peschke, S. B.; Müller, T.;
   Boehnhardt, H.; Brooke, T. Y.; Campins, H.; Crovisier, J.; Delahodde,
   C.; Heinrichsen, I.; Keller, H. U.; Knacke, R. F.; Krüger, H.; Lamy,
   P.; Leinert, Ch.; Lemke, D.; Lisse, C. M.; Müller, M.; Osip, D. J.;
   Solc, M.; Stickel, M.; Sykes, M.; Vanysek, V.; Zarnecki, J.
2001A&A...377.1098G    Altcode:
  Comet Hale-Bopp was observed five times with ISOPHOT, the photometer
  on board ESA's Infrared Space Observatory (ISO) between 4.6 and 2.8
  AU. Each time, broadband photometry was performed using 4 different
  detectors, 5 apertures and 10 filters covering the range between 3.6
  and 170 mu m. Background observations were performed with identical
  instrument settings at the same positions on the sky several days
  after the comet observations. The observation strategy and the data
  reduction steps are described in some detail, including the techniques
  to correct for variable detector responsivity. The resulting inband
  power values of the Hale-Bopp observations and their uncertainties are
  given. The mean uncertainty is 25%. The final fluxes were computed,
  taking into account the zodiacal background, possible offset of the
  comet's position from the center of the aperture, the brightness
  distribution within the coma, and the spectral energy distribution
  of the comet's emission. Strong thermal emission from a broad size
  distribution of dust particles was detected in all of the data sets,
  even at r=4.6-4.9 AU pre-perihelion and 3.9 AU post-perihelion; the
  total thermal energy varied as r<SUP>-3</SUP>. The 7.3-12.8 mu m color
  temperature was ~ 1.5 times the blackbody temperature, higher than
  that observed in any other comet. Silicate features at 10 and 25 mu m
  were prominent in all 5 data sets, the largest heliocentric distances
  that silicate emission has been detected in a comet. The presence of
  crystalline water ice grains is suggested from the 60 mu m excess
  emission at 4.6-4.9 AU, consistent with the observed Q<SUB>mathrm
  {OH</SUB>} if the icy grains were slightly warmer than an equilibrium
  blackbody. The average albedo of the dust is higher than that of comet
  P/Halley, but lower than other albedo measurements for Hale-Bopp nearer
  perihelion. There is no evidence for a component of cold, bright icy
  grains enhancing the scattered light at 4.6 AU. Simple models for a
  mixture of silicate and absorbing grains were fit to the ISO spectra
  and photometry at 2.8 AU. The observed flux at lambda &gt; 100 mu m
  requires a size distribution in which most of the mass is concentrated
  in large particles. Dust production rates of order 1.5x 10<SUP>5</SUP>
  kg s<SUP>-1</SUP> at 2.8 AU and 3x 10<SUP>4</SUP> kg s<SUP>-1</SUP>
  at 4.6 AU have been found. They correspond to dust to gas mass ratios
  of 6 to 10. With supporting observations by ISOCAM, SWS, LWS, and
  ground-based observations at the European Southern Observatory at La
  Silla in Chile.

---------------------------------------------------------
Title: Solar Polar Plume Lifetime and Coronal Hole Expansion:
    Determination from Long-Term Observations
Authors: DeForest, C. E.; Lamy, P. L.; Llebaria, A.
2001ApJ...560..490D    Altcode:
  We have generated off-limb polar synoptic charts of polar plume
  evolution at various solar altitudes using EUV Imaging Telescope and
  Large Angle and Spectrometric Coronagraph data from 1996 December. The
  charts allow direct measurement of the altitude expansion of the solar
  minimum coronal holes. We find expansion values that are consistent with
  the conventional picture of superradial expansion and inconsistent with
  radial expansion. Using visible red line data as a bridge between EUV
  and white-light images of the corona, we are able to confirm that the
  coronal structure seen at the base of the corona is preserved throughout
  the considered altitude range of 1.1-3.0 R<SUB>solar</SUB>. We show that
  polar plumes are episodic in nature, lasting perhaps 24 hr but recurring
  for up to weeks at a time; this strengthens the picture that they are
  caused by magnetic heating under the influence of supergranulation.

---------------------------------------------------------
Title: HST and VLT Investigations of the Fragments of Comet C/1999 S4
    (LINEAR)
Authors: Weaver, H. A.; Sekanina, Z.; Toth, I.; Delahodde, C. E.;
   Hainaut, O. R.; Lamy, P. L.; Bauer, J. M.; A'Hearn, M. F.; Arpigny,
   C.; Combi, M. R.; Davies, J. K.; Feldman, P. D.; Festou, M. C.; Hook,
   R.; Jorda, L.; Keesey, M. S. W.; Lisse, C. M.; Marsden, B. G.; Meech,
   K. J.; Tozzi, G. P.; West, R.
2001Sci...292.1329W    Altcode:
  At least 16 fragments were detected in images of comet C/1999 S4
  (LINEAR) taken on 5 August 2000 with the Hubble Space Telescope (HST)
  and on 6 August with the Very Large Telescope (VLT). Photometric
  analysis of the fragments indicates that the largest ones have
  effective spherical diameters of about 100 meters, which implies that
  the total mass in the observed fragments was about 2 × 10<SUP>9</SUP>
  kilograms. The comet's dust tail, which was the most prominent optical
  feature in August, was produced during a major fragmentation event,
  whose activity peaked on UT 22.8 +/- 0.2 July 2000. The mass of
  small particles (diameters less than about 230 micrometers) in the
  tail was about 4 × 10<SUP>8</SUP> kilograms, which is comparable
  to the mass contained in a large fragment and to the total mass lost
  from water sublimation after 21 July 2000 (about 3 × 10<SUP>8</SUP>
  kilograms). HST spectroscopic observations during 5 and 6 July 2000
  demonstrate that the nucleus contained little carbon monoxide ice
  (ratio of carbon monoxide to water is less than or equal to 0.4%),
  which suggests that this volatile species did not play a role in the
  fragmentation of C/1999 S4 (LINEAR).

---------------------------------------------------------
Title: Projective Transform Techniques to Reconstruct the 3-D
    Structure and the Temporal Evolution of Solar Polar Plumes
Authors: Llebaria, A.; Thernisien, A.; Lamy, P.
2001ASPC..238..377L    Altcode: 2001adass..10..377L
  A sequence of 400 images obtained over three days with the C2-LASCO/SOHO
  coronagraph was used to disentangle the complex evolution of the
  structures observed on the corona of the Sun's North pole. Projective
  transforms were used to find and delimit the elusive linear structures
  on each image (&lt; 1:1 of SNR). From frame to frame, these structures
  show strong brightness variations as well as lateral shifts which
  are linked to rotation of the Sun. Taking advantage of solar corona
  rotation as a rigid body (of ~28 days period), we are able to extract
  short sinograms to obtain a 3-D reconstruction with few hypotheses. The
  whole procedure is described, emphasizing the role of the bilinear
  transform as a new tool in this process.

---------------------------------------------------------
Title: Division III: Planetary Systems Sciences
Authors: Marov, Mikhail Ya.; A'Hearn, G. M. F.; Baggaley, J.; Bowell,
   E.; Bowyer, S.; Cruikshank, D.; de Bergh, C.; Keller, H.; Lamy, P.;
   Porubcan, V.; Watanabe, J.; Williams, I.; Zappala, V.
2001IAUTB..24..113M    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Mars NetLander panoramic camera
Authors: Jaumann, Ralf; Langevin, Yves; Hauber, Ernst; Oberst,
   Jürgen; Grothues, Hans-Georg; Hoffmann, Harald; Soufflot, Alain;
   Bertaux, Jean-Loup; Dimarellis, Emmanuel; Mottola, Stefano; Bibring,
   Jean-Pierre; Neukum, Gerhard; Albertz, Jörg; Masson, Philippe; Pinet,
   Patrick; Lamy, Philippe; Formisano, Vittorio
2000P&SS...48.1377J    Altcode:
  The panoramic camera (PanCam) imaging experiment is designed to
  obtain high-resolution multispectral stereoscopic panoramic images
  from each of the four Mars NetLander 2005 sites. The main scientific
  objectives to be addressed by the PanCam experiment are (1) to locate
  the landing sites and support the NetLander network sciences, (2)
  to geologically investigate and map the landing sites, and (3) to
  study the properties of the atmosphere and of variable phenomena. To
  place in situ measurements at a landing site into a proper regional
  context, it is necessary to determine the lander orientation on
  ground and to exactly locate the position of the landing site with
  respect to the available cartographic database. This is not possible
  by tracking alone due to the lack of on-ground orientation and the
  so-called map-tie problem. Images as provided by the PanCam allow
  to determine accurate tilt and north directions for each lander and
  to identify the lander locations based on landmarks, which can also
  be recognized in appropriate orbiter imagery. With this information,
  it will be further possible to improve the Mars-wide geodetic control
  point network and the resulting geometric precision of global map
  products. The major geoscientific objectives of the PanCam lander
  images are the recognition of surface features like ripples, ridges and
  troughs, and the identification and characterization of different rock
  and surface units based on their morphology, distribution, spectral
  characteristics, and physical properties. The analysis of the PanCam
  imagery will finally result in the generation of precise map products
  for each of the landing sites. So far comparative geologic studies
  of the Martian surface are restricted to the timely separated Mars
  Pathfinder and the two Viking Lander Missions. Further lander missions
  are in preparation (Beagle-2, Mars Surveyor 03). NetLander provides the
  unique opportunity to nearly double the number of accessible landing
  site data by providing simultaneous and long-term observations at four
  different surface locations which becomes especially important for
  studies of variable surface features as well as properties and phenomena
  of the atmosphere. Major changes on the surface that can be detected by
  PanCam are caused by eolian activities and condensation processes, which
  directly reflect variations in the prevailing near-surface wind regime
  and the diurnal and seasonal volatile and dust cycles. Atmospheric
  studies will concentrate on the detection of clouds, measurements of
  the aerosol contents and the water vapor absorption at 936 nm. In order
  to meet these objectives, the proposed PanCam instrument is a highly
  miniaturized, dedicated stereo and multispectral imaging device. The
  camera consists of two identical camera cubes, which are arranged in a
  common housing at a fixed stereo base length of 11 cm. Each camera cube
  is equipped with a CCD frame transfer detector with 1024×1024 active
  pixels and optics with a focal length of 13 mm yielding a field-of-view
  of 53°×53° and an instantaneous filed of view of 1.1 mrad. A filter
  swivel with six positions provides different color band passes in the
  wavelength range of 400-950 nm. The camera head is mounted on top of a
  deployable scissors boom and can be rotated by 360° to obtain a full
  panorama, which is already covered by eight images. The boom raises
  the camera head to a final altitude of 90 cm above the surface. Most
  camera activities will take place within the first week and the
  first month of the mission. During the remainder of the mission, the
  camera will operate with a reduced data rate to monitor time-dependent
  variations on a daily basis. PanCam is a joint German/French project
  with contributions from DLR, Institute of Space Sensor Technology
  and Planetary Exploration, Berlin, Institut d'Astrophysique Spatiale,
  CNRS, Orsay, and Service d'Aéronomie, CNRS, Verrières-le-Buisson.

---------------------------------------------------------
Title: The nucleus of 13 short-period comets
Authors: Lamy, P. L.; Toth, I.; Weaver, H. A.; Delahodde, C.; Jorda,
   L.; A'Hearn, M. F.
2000DPS....32.3604L    Altcode: 2000BAAS...32.1061L
  We report the successful detection of the nucleus of 13 short-period
  comets with the Hubble Space Telescope. One orbit was devoted to each
  comet and the observations were performed with the Planetary Camera
  and at least two filters (V and R) and up to four (B, V, R, I) for the
  brightest ones. Assuming spherical nuclei with a geometric albedo of
  0.04 for the R band and a phase law of 0.04 mag/deg, we determined the
  following radii: 4P/Faye: 1.77 km; 10P/Tempel 2: 4.60 km; 17P/Holmes:
  1.71 km; 37P/Forbes: 0.81 km; 44P/Reinmuth 2: 1.63 km; 50P/Arend: 0.95
  km; 59P/Kearns-Kwee: 0.79 km; 63P/Wild 1: 1.46 km; 71P/Clark: 0.68
  km; 84P/Giclas: 0.90 km; 106P/Schuster: 0.94 km; 112P/Urata-Niijima:
  0.90 km; 114P/Wiseman-Skiff: 0.78 km. We also obtained the spectral
  reflectivities of those nuclei and of their coma and calculated the
  dust production rates.

---------------------------------------------------------
Title: Detailed Phase Function of a Comet Nucleus: 28P/Neujmin 1
Authors: Delahodde, C. E.; Hainaut, O. R.; Lamy, P. L.; Meech, K. J.
2000DPS....32.3609D    Altcode: 2000BAAS...32.1062D
  Very little is known on the surface properties of cometary nuclei --
  with the notable exception of the in-situ measurements for comet
  Halley. A still unexplored method of investigation is the study of
  the solar phase function, which can give us direct information on
  the surface roughness as well as some independent constraints on the
  albedo. In order to estimate properly the Hapke parameters describing
  the phase function, one has to obtain measurements not only over a broad
  phase angle (α ) range, but also at very small phase angle, in order
  to sample the “opposition surge”, a brightening of the phase curve
  occurring at α &lt; 2-3<SUP>o</SUP>. In 2000, Comet 28P/Neujmin 1 was
  an ideal candidate for a phase function study: its April opposition
  was almost ideal (α = 0.8° ), and previous observations by Meech
  et al. at similar heliocentric distances (r<SUB>h</SUB> &gt;= 4 AU)
  indicated that the comet was likely not to be active. We observed
  this comet using ESO's NTT and 2.2m telescopes at La Silla, on 6
  epochs from April to August 2000, covering α = 0.8 - 8<SUP>o</SUP> ,
  with a good sampling of the opposition surge. In order to disentangle
  the rotation effects from the phase effects, we obtained a complete
  rotation coverage at opposition, providing us with a light-curve
  template. For each subsequent epoch, we have obtained enough rotation
  coverage to re-synchronize the light-curve fragments with the template,
  and determine the magnitude change caused by the phase function. Using
  these data, we hope to present the first detailed comet nucleus phase
  function, and compare it with known C-type asteroids.

---------------------------------------------------------
Title: Spectral properties of the nucleus of short-period comets
Authors: Toth, I.; Lamy, P. L.
2000DPS....32.3705T    Altcode: 2000BAAS...32.1063T
  Comets, Edgeworth-Kuiper-Belt Objects (EKBOs), Centaurs and low albedo
  asteroids contain a considerable amount of information regarding some
  of the primordial processes that governed the formation of the early
  Solar System planetesimals. Opportunities to determine the colors
  of cometary nuclei are rare and relevant ground-based observations
  are difficult to perform. Color diversities and similarities between
  different types of small bodies have already been considered ([1] and
  references therein). We pursue this analysis further by introducing new
  BVRI colors obtained from our survey of cometary nuclei with the Hubble
  Space Telescope [2] as well as recent data obtained on EKBOs. We present
  preliminary results on the distribution of the BVRI colors (histograms,
  two-color diagrams) and possible relationships between the colors
  and orbital elements as well as the determined body sizes. The mean
  colors of the selected sample of the short-period (s-p) comets are:
  &lt; (B-V) &gt; = 0.91, &lt; (V-R) &gt; = 0.52, and &lt; (V-I) &gt; =
  0.84. Pearson's linear correlation analysis of the (B-V) versus (V-R)
  and (V-R) versus (V-I) colors show significant correlations for the
  EKBOs+Centaurs sample while the s-p sample seems to be uncorrelated,
  with a few outliers. The linear regression lines of the EKBOs+Centaurs
  sample crosses through the sample of the s-p comets. There are no
  correlations of the colors versus perihelion distances, effective
  radii and perihelion distances as well as the (a,sin(i)) diagrams. This
  work was supported by grants from CNRS and CNES, France and partially
  by the the Hungarian Research Foundation OTKA T025049. [1] Luu, J.,
  1993. Icarus 104, 138. [2] Lamy, P.L. et al., this conference

---------------------------------------------------------
Title: HST and VLT Investigations of the Fragments of C/1999 S4
    (LINEAR)
Authors: Weaver, H. A.; West, R.; A'Hearn, M. F.; Arpigny, C.; Bauer,
   J. M.; Combi, M. R.; Davies, J. K.; Delahodde, C. E.; Feldman, P. D.;
   Fes tou, M. C.; Hainaut, O. R.; Hook, R.; Jorda, L.; Keesey, M. S. W.;
   Lamy, P. L.; Lisse, C. M.; Marsden, B. G.; Meech, K. J.; Sekanina,
   Z.; Toth, I.; Tozzi, G. -P.
2000DPS....32.3606W    Altcode: 2000BAAS...32.1061W
  Observations of C/1999 S4 (LINEAR) with the Hubble Space Telescope
  (HST) on 2000 August 5.167--5.467 UT and with the Very Large Telescope
  (VLT) on August 6.978--6.999 UT revealed the presence of over 17
  fragments following the breakup of the nucleus in late July. Nearly
  half the fragments were located in a “swarm” near the western “tip”
  of the dust tail (i.e., the sunward side of the tail), but several
  were significantly sunward of the tip, including one object that we
  tentatively identify as the primary remnant of the original nucleus. The
  correspondence between fragments in the HST and VLT images is generally
  very good, but the brightest fragment in the HST image is not seen in
  the VLT image, indicating rapid variability in activity. The dynamic
  nature of the fragments was further highlighted by a dramatic change
  in the appearance of the fragments in VLT images taken during August
  9.976--9.996 UT, when they were barely detectable. The locations
  and brightnesses of the fragments will be presented, along with a
  discussion of the dynamics associated with the breakup event and its
  subsequent evolution. We thank the Directors of the Space Telescope
  Science Institute and the ESO/VLT for approving our observing programs
  for Director's Discretionary Time.

---------------------------------------------------------
Title: Properties of 2060 Chiron from infrared ISOPHOT observations
Authors: Groussin, O.; Peschke, S.; Lamy, P. L.
2000DPS....32.2105G    Altcode: 2000BAAS...32.1031G
  We present the analysis of new observations of 2060 Chiron with
  the Infrared Space Observatory (ISO). They were performed with the
  ISO photometer (ISOPHOT) from 8 to 15 June 1996, when Chiron was
  near perihelion at a heliocentric distance of 8.46 AU, using four
  filters centered at 25, 60, 100 and 160 μ m. The observed fluxes
  are fitted to a thermal model which considers a mixture of water ice
  and refractory materials on the surface and includes heat conduction
  into the interior of the nucleus. We derive a thermal inertia of 10
  JK<SUP>-1</SUP>m<SUP>-2</SUP>s<SUP>-1/2</SUP>. Combining the present IR
  data with visible observations by Luu (1990) and Marcialis (1993), we
  determine a radius of 80+/-10 km and a geometric albedo of 0.14+/-0.02.

---------------------------------------------------------
Title: Observation of the origin of CMEs in the low corona
Authors: Delannée, C.; Delaboudinière, J. -P.; Lamy, P.
2000A&A...355..725D    Altcode:
  The aim of the main observing program with EIT on board SOHO,
  is to monitor the whole Sun surface in the Fe xii emission line
  at 195 Ä, every 17 minutes. The very beginning of some CMEs can
  be observed. We interpret Fe xii images in conjunction with He ii,
  Hα and coronagraph observations over a period of 6 days. We find
  that 7 prominences produced ejections. An active region produced 9
  ejections. Five ejections are seen as dark bubbles propagating above
  the solar limb while 9 are seen as dimmings on the solar surface. The
  3 other ejections are bright bubbles observed rising up above the
  limb. Thirteen of the 17 observed ejections are related to a CME. Two
  CMEs of the 15 CMEs observed with LASCO C2 are not related to Fe xii
  low corona events. Probably, these CMEs have their origin behind the
  limb. Prominences give rise to quite slow CMEs, 50-120 km s<SUP>-1</SUP>
  while fast CMEs, 110-1000 km s<SUP>-1</SUP>, originate close to active
  regions. We conclude that CMEs start in the low corona and that large
  scale coronal structures reconfigurations occur when these disturbances
  propagate outward.

---------------------------------------------------------
Title: Properties of coronal mass ejections: SOHO LASCO observations
    from January 1996 to June 1998
Authors: St. Cyr, O. C.; Plunkett, S. P.; Michels, D. J.; Paswaters,
   S. E.; Koomen, M. J.; Simnett, G. M.; Thompson, B. J.; Gurman, J. B.;
   Schwenn, R.; Webb, D. F.; Hildner, E.; Lamy, P. L.
2000JGR...10518169S    Altcode: 2000JGR...105.8169S; 2000JGRA..105.8169S
  We report the properties of all the 841 coronal mass ejections (CMEs)
  observed by the Solar and Heliospheric Observatory (SOHO) Large Angle
  Spectroscopic Coronagraph (LASCO) C2 and C3 white-light coronagraphs
  from January 1996 through June 1998, and we compare those properties to
  previous observations by other similar instruments. Both the CME rate
  and the distribution of apparent locations of CMEs varied during this
  period as expected based on previous solar cycles. The distribution
  of apparent speeds and the fraction of CMEs showing acceleration were
  also in agreement with earlier reports. The pointing stability provided
  by an L-1 orbit and the use of CCD detectors have resulted in superior
  brightness sensitivity for LASCO over earlier coronagraphs; however, we
  have not detected a significant population of fainter (i.e., low mass)
  CMEs. The general shape of the distribution of apparent sizes for LASCO
  CMEs is similar to those of earlier reports, but the average (median)
  apparent size of 72° (50°) is significantly larger. The larger
  average apparent size is predominantly the result of the detection of
  a population of partial and complete halo CMEs, at least some of which
  appear to be events with a significant longitudinal component directed
  along the Sun-Earth line, either toward or away from the Earth. Using
  full disk solar images obtained by the Extreme ultraviolet Imaging
  Telescope (EIT) on SOHO, we found that 40 out of 92 of these events
  might have been directed toward the Earth, and we compared the timing
  of those with the Kp geomagnetic storm index in the days following
  the CME. Although the “false alarm” rate was high, we found that 15
  out of 21 (71%) of the Kp&gt;=6 storms could be accounted for as SOHO
  LASCO/EIT frontside halo CMEs. If we eliminate three Kp storms that
  occurred following LASCO/EIT data gaps, then the possible association
  rate was 15 out of 18 (83%).

---------------------------------------------------------
Title: Commission 21: Light of the Night Sky: (Lumiere du Ciel
    Nocturne)
Authors: Bowyer, S.; Lamy, P.; Dwek, E.; Gustafson, B.; Hanner,
   M.; Levasseur-Regourd, A. Ch.; Mikhail, J.; Mann, I.; Mukai, T.;
   Matsumoto, T.
2000IAUTA..24..152B    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: ISOCAM Observations of Cometary Nuclei
Authors: Jorda, L.; Lamy, P.; Groussin, O.; Toth, I.; A'Hearn, M. F.;
   Peschke, S.
2000ESASP.455...61J    Altcode: 2000ibps.conf...61J
  ISOCAM images of comets C/1995 O1 (Hale-Bopp), 22P/Kopff, 46P/Wirtanen,
  55P/Tempel-Tuttle, 103P/Hartley and 126P/IRAS were obtained between
  7.8 and 15 microns in Oct.-Nov. 1996 and Jan.-Feb. 1998 in order to
  characterize their nucleus by detecting their thermal emission. All
  images were corrected for the dark current, detector non-uniformity and
  transient effects with standard methods available in CIA V3.0. Further
  IDL based processing is performed to correct the images from the
  overshot, preserve the nuclear region from glitch removal and eliminate
  images with a high percentage of glitches. The signal from the nucleus
  was measured by fitting the data with a model including the contribution
  from both the coma and the nucleus. By combining the thermal fluxes with
  the visible fluxes, obtained with the same technique from HST images,
  we derived the size and geometric albedo of three comets (C/1995 O1,
  22P and 55P). For comets 103P and 126P, we only derived their size. The
  radii range from 0.56 km (103P) to 56 km (C/1995 O1). The determined
  geometric albedos are between 0.02 and 0.07, in agreement with previous
  measurements on several other nuclei.

---------------------------------------------------------
Title: Coronal Mass Ejections and Large Scale Structure of the Corona
Authors: Maia, D.; Vourlidas, A.; Pick, M.; Howard, R.; Schwenn, R.;
   Lamy, P.
2000AdSpR..25.1843M    Altcode:
  A comparative study of two events accompanied by both a flare and a
  CME has been performed. The data analysis has been made by comparing
  the observations of the LASCO/SOHO coronagraphs with those of the
  Nancay radioheliograph. The observations show a clear connection
  between coronal green and red line transient activity, burst radio
  emission and the CME development which is due to successive loop
  interactions. Signatures of these interactions are given by the radio
  emission. One can identify successive sequences in the evolution
  of the coronal restructuring leading to the full development of the
  CME. Identification and timing of these sequences result from the radio
  emission analysis. For flare-CME events , the evolution takes place
  in the low corona and is extremely fast of the order, on a few minutes

---------------------------------------------------------
Title: CMEs Observed Continuously from the Lower Corona to the
    Far Corona
Authors: Delannée, C.; Delaboudinière, J. -P.; Lamy, P.
2000AdSpR..26...67D    Altcode:
  A campaign of observations with EIT on board SOHO called “CME watch”,
  is designed to observe the whole sun surface in 195 A&amp;ring i.e. in a
  Fe XII emission line, every 17 minutes. In order to analyze the events,
  we also used He II and coronagraph observations of 97/11/03. By this
  way, the very beginning of some CMEs was observed. The ejections
  were seen in Fe XII as a dark bubble propagating in the corona
  above a prominence, and dimmings produced near an active region and
  propagating on the solar surface. Two of the ejections coming from
  the active region were produced with a very short time of delay (1
  hour). All the ejections were associated to a CME. However, one CME
  was not related to a Fe xII low corona event, but maybe this CME had
  its origin behind the limb. The CME associated with the prominence
  was quite slow (50 km s<SUP>-1</SUP>) and the ones associated with
  the active region were quite fast (114-490 km s<SUP>-1</SUP>). This
  analysis permitted a better identification of the different CMEs
  appearing in the coronagraph field of view

---------------------------------------------------------
Title: Eclipse of August 11, 1999: White-light Images and Simultaneous
    EIT/SOHO Observations
Authors: Adjabshirizadeh, A.; Baudin, F.; Bocchialini, K.;
   Delaboudinière, J. -P.; Grorod, P. -A.; Koutchmy, S.; Laal Aaly,
   M.; Lamy, P.; Lochard, J.; Mouette, J.
1999ESASP.448.1283A    Altcode: 1999ESPM....9.1283A; 1999mfsp.conf.1283A
  No abstract at ADS

---------------------------------------------------------
Title: The Global Activity of the Solar Corona
Authors: Llebaria, A.; Lamy, P.; Koutchmy, S.
1999ESASP.446..441L    Altcode: 1999soho....8..441L
  The question of the global activity of the solar corona, as a function
  of time and distance from the center of the Sun, is considered by
  analyzing long time-series of LASCO-C2 images. Polarized images
  are first considered to perform the separation of the K and F
  components. The F-corona images are used to construct a photometric
  model of the F-corona wich reflects its annual variations resulting from
  geometric effects. This time-varying model is then subtracted from all
  corrected and calibrated images (unpolarized) to yield images of the
  K-corona. Synoptic maps are created at different distances between 2.5
  and 6 solar radii and the total white-light intensity is integrated to
  estimate the total mass of the corona. Its variations in the range of
  heliocentric distance and over a time span of 3 years will be presented
  and discussed.

---------------------------------------------------------
Title: Monolithic SiC telescope of the OSIRIS Narrow-Angle Camera
    for the cometary mission ROSETTA
Authors: Castel, Didier; Calvel, Bertrand; Lamy, Philippe L.; Dohlen,
   Kjetil; Bougoin, Michel
1999SPIE.3785...56C    Altcode:
  The international Rosetta mission, now planned by ESA to be launched
  in January 2003, will provide a unique opportunity to directly study
  the nucleus of comet 46P/Wirtanen and its activity from a heliocentric
  distance of 3.2 AU to the perihelion passage at 1.06 AU in July 2013. We
  describe here the design, the development and the performances of
  the telescope of the Narrow Angle Camera of the OSIRIS experiment
  which will give high resolution images of the cometary nucleus in the
  visible spectrum.

---------------------------------------------------------
Title: Simultaneous LASCO/1998-Eclipse Observations Of A Large-Scale
    Polar Event
Authors: Zhukov, A.; Koutchmy, S.; Lamy, Ph.; Delaboudinière,
   J. -P.; Delannée, C.; Bocchialini, K.; Guisard, S.; Filippov, B.;
   Veselovsky, I.
1999ESASP.446..731Z    Altcode: 1999soho....8..731Z
  A relatively faint but large scale polar region event was observed
  in Aug. 1996 by Boulade et al. 1998 (SoHO SP 404, 217); we first
  reconsider this event which has been related to a high latitude
  filament disappearance. We continue the study of this class of events by
  analyzing the large scale restructuring which occurred above the N-Pole
  region at the time of the last Feb. 26, 1998 total solar eclipse. Well
  calibrated WL-eclipse images are used to provide the absolute values
  of electron densities of the quasi-radial structure appearing at
  the feet of the event. This structure can also be considered as a
  type of abnormally broad and curved polar plume, a type of activity
  already reported in the literature. Unfortunately, the examination
  of sequences of EIT images taken at that time seems to indicate that
  the roots of the structure are on the back side of the Sun. However
  the most impressive effects are seen in the high polar region, at
  several radii, based on the analysis of processed Lasco-C2 difference
  images. Large proper motions are deduced over density structures. Both
  these events confirm that polar regions are indeed showing a new class
  of CME activity (possibly related to the Hewish's CMEs), which is seen
  inside coronal holes. A whole set of interesting questions is then
  appearing to understand the occurrence of a polar CME propagating in
  the heart of a large unipolar magnetic region of the corona.

---------------------------------------------------------
Title: Characterization of the nucleus of comet Hale-Bopp from HST
    and ISO observations
Authors: Lamy, P.; Jorda, L.; Toth, I.; Groussin, O.; A'Hearn, M. F.;
   Weaver, H. A.
1999DPS....31.2703L    Altcode:
  High resolution images were obtained in the visible with the Planetary
  Camera of the Hubble Space Telescope and "B,V,R" filters and in the
  thermal infrared with ISOCAM and from filters centered at 7.75, 9.62,
  11.4 and 15.0 micron. The latter images were carefully processed to
  independently correct for the temporal evolution of the signal in each
  pixel. Using our standard technics, we separated the nuclear and comatic
  contributions to retrieve the flux from the nucleus. Two thermal models
  were used to interpret the infrared fluxes, the Standard Thermal Model
  (STM) and a mixed ice-dust model. Combining the visible and thermal
  data, the STM model suggests a body with a radius of 35+/-6 km with
  an albedo of 0.05+/-0.02 and a maximum temperature of 254 K while the
  mixed model indicates a larger radius 52+/-5 km and a lower maximum
  temperature of 192 K. The spectral energy distribution is best fit
  with the mixed ice-dust model with an excess at 10 micron attributed
  to the silicate band.

---------------------------------------------------------
Title: The sungrazing comets discovered with the SOHO/LASCO
coronagraphs: 1996-1998.
Authors: Biesecker, D. A.; Lamy, P.; St. Cyr, O. C.; Llebaria, A.;
   Howard, R.
1999DPS....31.1404B    Altcode:
  An unprecedented number of Kreutz sungrazing comets have been discovered
  with the LASCO coronagraphs on the SOHO spacecraft. We present here
  the results of the analysis of the first 53 sungrazing comets, which
  were discovered between January, 1996 and June, 1998. In this poster, we
  summarize the capabilities and calibration of the LASCO coronagraphs for
  comet observations. We discuss the frequency of the comet discoveries
  and summarize the properties of the computed orbits. We show examples
  of typical comet light curves and discuss their common features. In
  particular, we show that the comets are completely disintegrated before
  they reach perihelion. One particular feature of the observations is
  the presence of a dust tail for only a few sungrazers while no tail
  is evident for the majority of them. Analysis of the light curves is
  used to investigate the properties of the nuclei (size, fragmentation,
  destruction) and the dust production rates. This work was funded in
  part by NASA SOHO-GI Grant NAG5-8003.

---------------------------------------------------------
Title: The sungrazing comets discovered with the SOHO/LASCO
coronagraphs: 1996-1998.
Authors: Biesecker, D. A.; Lamy, P.; St. Cyr, O. C.; Llebaria, A.;
   Howard, R.
1999BAAS...31.1094B    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Experiments for in-situ monitoring of dust environments in
    the Solar System
Authors: Colangeli, L.; Bussoletti, E.; Lopez Moreno, J. J.; Epifani,
   E.; Esposito, F.; Mennella, V.; Palomba, E.; Palumbo, P.; Rotundi,
   A.; Vergara, S.; Jeronimo, J. M.; Lopez-Jimenez, A. C.; Molina, A.;
   Morales, R.; Moreno, F.; Olivares, I.; Rodrigo, R.; Rodriguez-Gomez,
   J. F.; Ruiz-Falco, A.; Sanchez, J.; McDonnell, J. A. M.; Leese, M.;
   Lamy, P.; Perruchot, S.; Crifo, J. F.; Fulle, M.; Perrin, J. M.;
   Angrilli, F.; Coradini, A.; Giovane, F.; Gruen, E.; Gustafson, B.;
   Maag, C.; Weissman, P. R.
1999DPS....31.2906C    Altcode:
  "Dust" is present in the Solar System, from planetary surfaces
  to comets. The in-situ monitoring of its physical and dynamical
  properties is one of the main scientific tasks to be achieved in order
  to characterise grains and to correctly understand their role in the
  evolution of Solar System bodies. A new generation of methods for
  in-situ exploration of dusty environments in the Solar System has been
  studied and adopted in different instruments under development or study
  for future planetary space missions. Mass flux measurements by quartz
  crystal microbalances, optical detection of single grains and momentum
  monitoring by piezoelectric transducers are techniques which provide
  high sensitivity for grains at relatively low (below some hundreds m/s)
  velocities. The GIADA (Grain Impact Analyser and Dust Accumulator)
  experiment is part of the payload of the ESA Rosetta orbiter, targeted
  to a rendez-vous of 46P/Wirtanen comet. Thanks to GIADA, one of the
  prime scientific objectives of the mission will be fulfilled, i.e. the
  monitoring of the cometary coma dust environment. The dust flux from
  different directions vs. time and the momentum and velocity vs. mass
  of particles will be measured, while comet will approach the Sun. The
  MAGO (Martian Atmospheric Grain Observer) instrument, under study in
  the framework of the next Mars exploration opportunities (e.g.: Mars
  Surveyor Program 2003) adopts similar technical solutions and is aimed
  at measuring, directly for the first time, the dust mass flux in the
  Martian atmosphere and the dynamical properties of airborne particles
  vs. time. Finally, similar measurement techniques can be integrated with
  other detection/collection systems (e.g. aerogel collectors) to monitor
  the dust in the near Earth environment, e.g. from the space station.

---------------------------------------------------------
Title: Characterization of the nucleus of comet Hale-Bopp from HST
    and ISO observations.
Authors: Lamy, P.; Jorda, L.; Toth, I.; Groussin, O.; A'Hearn, M. F.;
   Weaver, H. A.
1999BAAS...31.1116L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Hubble Space Telescope Observations of the Nucleus of Comet
    45P/Honda-Mrkos-Pajdusakova and Its Inner Coma
Authors: Lamy, P. L.; Toth, I.; A'Hearn, M. F.; Weaver, H. A.
1999Icar..140..424L    Altcode:
  The nucleus of Comet 45P/Honda-Mrkos-Pajdusakova was detected during
  Hubble Space Telescope observations taken with the Wide-Field Planetary
  Camera 2 (WFPC2) in February 1996 when the comet was 0.17 AU from the
  Earth. The high spatial resolution (1 pixel projected to 5.6 km at
  the distance of the comet) allowed us to separate the signal of the
  nucleus from that of the coma, and images taken through five broadband
  filters allowed us to determine the UBVRI magnitudes of the nucleus
  in the Johnson-Kron-Cousins photometric system (sometime known as the
  Landolt system). Assuming a spherical body whose geometric albedo
  is 0.04 for the V band and a phase coefficient of 0.04 mag/deg, we
  derive an effective radius of 0.34 km. The uncertainty is dominated
  by the unknown phase law; the radius may be as small as 0.22 km if
  the phase coefficient is 0.03 mag/deg. The correlated variations of
  the magnitudes over 1 day suggest an elongated body with an axis
  ratio of at least 1.3. The strong reddening of the nucleus in the
  ultraviolet progressively decreases, and its color tends to neutral
  in the near infrared. We also derive a fractional active area of 11%
  and a dust production rate of 1.0 kg s<SUP>-1</SUP> (86 metric tons
  day<SUP>-1</SUP>).

---------------------------------------------------------
Title: Streamer disconnection events observed with the LASCO
    coronagraph
Authors: Wang, Y. -M.; Sheeley, N. R., Jr.; Howard, R. A.; Rich,
   N. B.; Lamy, P. L.
1999GeoRL..26.1349W    Altcode:
  We present Large Angle Spectrometric Coronagraph (LASCO) observations
  of two events that suggest magnetic disconnection in coronal
  streamers. During the 1-2 days preceding each event, successions of
  narrow looptops are seen rising slowly through the 2-6 R<SUB>S</SUB>
  field of view, forming a bright streamer stalk which continues to
  elongate with time. As the streamer becomes ever more constricted, it
  eventually severs at a heliocentric distance of ∼4 R<SUB>S</SUB>. The
  lower part of the stalk collapses back to form a cusplike structure
  extending to ∼3 R<SUB>S</SUB>, while the disconnected segment is
  observed as a kink or density enhancement that propagates outward with
  a speed of order 200 km s<SUP>-1</SUP>. We interpret these non-CME
  events as transient openings and closings of magnetic flux rooted at
  the boundaries of coronal holes.

---------------------------------------------------------
Title: Influence of image compression on the in situ stereoscopic
    reconstruction of a cometary surface for the ROSETTA mission.
Authors: Takerkart, S.; Lamy, P.; Llebaria, A.
1999CRASB.327..547T    Altcode:
  As part of the ROSETTA mission, the surface science package, wich will
  land on the nucleus of the comet 46P/Wirtanen, includes a stereoscopic
  imaging instrument CIVA-P. The data volume required by the scientific
  objectives and the limited capability of the telemetry imposes the
  use of image-loss compression techniques. The authors study the
  influence of the losses due to compression on the three-dimensional
  surface reconstruction. They prove that the best strategy consists
  in compressing both the left and right images with the same ratio,
  transmitting them and finally applying on Earth the stereoscopic
  calculation on the decompressed images.

---------------------------------------------------------
Title: ISOPHOT observations of comet Hale-Bopp: initial data reduction
Authors: Grun, E.; Peschke, S. B.; Stickel, M.; Muller, T. G.; Kruger,
   H.; Bohmhardt, H.; Brooke, T. Y.; Campins, H.; Crovisier, J.; Hanner,
   M. S.; Heinrichsen, I.; Keller, H. U.; Knacke, R.; Lamy, P.; Leinert,
   C.; Lemke, D.; Lisse, C. M.; Muller, M.; Osip, D. J.; Solc, M.; Sykes,
   M.; Vanysek, V.; Zarnecki, J.
1999ESASP.427..181G    Altcode: 1999usis.conf..181G; 1998astro.ph.12171G
  Comet Hale-Bopp was observed five times with ISOPHOT, the photometer
  on board the Infrared Space Observatory (ISO). Each time broadband
  photometry was performed using 4 different detectors, 5 apertures and,
  10 filters covering the range between 3.6 to 175 μm. Calibration
  measurements using the internal Fine Calibration Source were done
  together with each individual measurement. Background observations were
  performed with identical instrument settings at the same positions on
  the sky several days after the comet observations. The observation
  strategy and the initial data reduction steps are described in
  some detail and the resulting in-band power values of the Hale-Bopp
  observations and their uncertainties are derived. Initial reduction
  of these measurements was performed in 3 steps: (1) processing of
  raw data by removing instrumental and energetic particle effects,
  (2) averaging of the individual signals, and (3) determination of the
  detector responsivities and their uncertainties. The detector signal is
  determined by two different methods and the best value is chosen. At the
  present level of processing uncertainties range from 10% to a factor
  of 3 for the low power levels at short wavelengths. The in-band power
  levels at different wavelengths varied over 3 orders of magnitude.

---------------------------------------------------------
Title: LASCO observations of the coronal rotation
Authors: Lewis, D. J.; Simnett, G. M.; Brueckner, G. E.; Howard,
   R. A.; Lamy, P. L.; Schwenn, R.
1999SoPh..184..297L    Altcode:
  The near-rigid rotation of the corona above the differential rotation
  of the photosphere has important implications for the form of the
  global coronal magnetic field. The magnetic reconfiguring associated
  with the shear region where the rigidly-rotating coronal field lines
  interface with the differentially-rotating photospheric field lines
  could provide an important energy source for coronal heating. We present
  data on coronal rotation as a function of altitude provided by the Large
  Angle Spectrometric Coronagraph (LASCO) instrument aboard the Solar and
  Heliospheric Observatory (SOHO) spacecraft. LASCO comprises of three
  coronagraphs (C1, C2, and C3) with nested fields-of-view spanning 1.1
  R⊙ to 30 R⊙. An asymmetry in brightness, both of the Fe xiv emission
  line corona and of the broad-band electron scattered corona, has been
  observed to be stable over at least a one-year period spanning May
  1996 to May 1997. This feature has presented a tracer for the coronal
  rotation and allowed period estimates to be made to beyond 15 R⊙,
  up to 5 times further than previously recorded for the white-light
  corona. The difficulty in determining the extent of differential motion
  in the outer corona is demonstrated and latitudinally averaged rates
  formed and determined as a function of distance from the Sun. The
  altitude extent of the low latitude closed coronal field region is
  inferred from the determined rotation periods which is important to the
  ability of the solar atmosphere to retain energetic particles. For the
  inner green line corona (&lt;2 R⊙) we determine a synodic rotation
  period of (27.4±0.1) days, whereas, for the outer white- light corona,
  (&gt;2.5 R⊙) we determine a rotation period of (27.7±0.1) days.

---------------------------------------------------------
Title: Time Domain Analysis of Solar Coronal Structures Through
    Hough Transform TEC hniques
Authors: Llebaria, A.; Lamy, P.
1999ASPC..172...46L    Altcode: 1999adass...8...46L
  The Hough transform technique is applied to a series of images
  from the LASCO/C2 coronagraph in order to understand the temporal
  evolution of radial structures on the solar corona, the so-called
  “polar plumes”. They may corotate with the solar corona and therefore
  change aspect with time due to projection effects on the plane of the
  sky. In the images these structures suddenly appear, shift, mix, and
  fade away on short periods of time. &gt;From a long series of images
  (~100), we determined for each image the polar intensity profile and
  built up the evolution of such profiles against time. The result is
  a Time Intensity Diagram (TID) where intensities are plotted with
  respect to time and position coordinates. Radial structures appear as
  peak intensities in each profile and therefore as bright points in the
  TID. The Hough transform techniques are applied to detect coherent
  trajectories. This technique has been applied successfully to study
  coronal plumes on coronal images obtained by different instruments
  aboard the SOHO satellite.

---------------------------------------------------------
Title: The GIADA Experiment for Rosetta Mission to Comet 46P/Wirtanen:
    Design and Performances
Authors: Bussoletti, E.; Colangeli, L.; Lopez Moreno, J. J.; Epifani,
   E.; Mennella, V.; Palomba, E.; Palumbo, P.; Rotundi, A.; Vergara, S.;
   Girela, F.; Herranz, M.; Jeronimo, J. M.; Lopez-Jimenez, A. C.; Molina,
   A.; Moreno, F.; Olivares, I.; Rodrigo, R.; Rodriguez-Gomez, J. F.;
   Sanchez, J.; McDonnell, J. A. M.; Leese, M.; Lamy, P.; Perruchot,
   S.; Crifo, J. F.; Fulle, M.; Perrin, J. M.; Angrilli, F.; Benini,
   E.; Casini, L.; Cherubini, G.; Coradini, A.; Giovane, F.; Grün, E.;
   Gustafson, B.; Maag, C.; Weissmann, P. R.
1999AdSpR..24.1149B    Altcode:
  Rosetta is one of the most ambitious missions planned by ESA for
  the beginning of the next millennium. It will explore from very
  close a comet nucleus along its trajectory up to perihelion. In the
  instrument complex forming the scientific payload, the GIADA (Grain
  Impact Analyser and Dust Accumulator) experiment is devoted to study
  the cometary dust flux evolution and grain dynamic properties. To
  achieve the required performances and the expected scientific return,
  GIADA has been designed as a multi-sensor instrument. It is able to
  detect grain passage by laser light scattering measurement, particle
  momentum through piezoelectric transducers and mass flux by means of
  quartz crystal microbalances. In this paper we describe the technical
  solutions and performances which have been reached on the development
  models of GIADA

---------------------------------------------------------
Title: Preface
Authors: Lamy, Philippe; Thomas, Nicolas
1999AdSpR..24.1079L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The panoramic camera of the ROSETTA mission: performances of
    prototype 3D microcameras
Authors: Beauvivre, S.; Lamy, P.; Nguyen-Trong, T.; Reynaud, J. -L.
1999AdSpR..24.1105B    Altcode:
  We present the evaluation of the performances of microcameras prototypes
  manufactured in 3D packaging technology developed for the panoramic
  camera of the lander for the ROSETTA cometary mission. Two different
  prototypes were tested, one manufactured by Alcatel and the other
  by CSEM. A specific laboratory setup with cooling capabilities was
  implemented to perform electrical, mechanical and photometric tests
  in the temperature range -90°C to +20°C. Our results show that
  the photometric performances are nominal and do not change in this
  temperature range. The reduced size of the camera, associated with
  its operating mode, leads to a transient thermal behaviour that does
  not affect the cameras properties when operated at temperatures below
  -55°C. We show that this kind of miniature camera is suitable to deep
  space missions like ROSETTA, provided specific cares are taken in the
  electrical and mechanical designs.

---------------------------------------------------------
Title: The GIADA experiment for ROSETTA mission to comet 46P/wirtanen:
    Design and performances
Authors: Bussoletti, E.; Colangeli, L.; Lopez Moreno, J. J.; Epifani,
   E.; Mennella, V.; Palomba, E.; Palumbo, P.; Rotundi, A.; Vergara, S.;
   Girela, F.; Herranz, M.; Jeronimo, J. M.; Lopez-Jimenez, A. C.; Molina,
   A.; Moreno, F.; Olivares, I.; Rodrigo, R.; Rodriguez-Gomez, J. F.;
   Sanchez, J.; McDonnell, J. A. M.; Leese, M.; Lamy, P.; Perruchot,
   S.; Crifo, J. F.; Fulle, M.; Perrin, J. M.; Angrilli, F.; Benini,
   E.; Casini, L.; Cherubini, G.; Coradini, A.; Giovane, F.; Grün, E.;
   Gustafson, B.; Maag, C.; Weissmann, P. R.
1999AdSpR..24.1139B    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Exploration of small bodies in the solar system: I. Initial
results and future prospects : proceedings of the B1.1 Symposium of
    COSPAR Scientific Commission B which was held during the Thirty-second
    COSPAR Scientific Assembly, Nagoya, Japan, 12-19 July, 1998
Authors: Lamy, P. L.; Thomas, N.
1999AdSpR..24.....L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Experiments for in-situ monitoring of dust environments in
    the Solar System.
Authors: Colangeli, L.; Bussoletti, E.; López-Moreno, J. J.; Epifani,
   E.; Esposito, F.; Mennella, V.; Palomba, E.; Palumbo, P.; Rotundi,
   A.; Vergara, S.; Jeronimo, J. M.; Lopez-Jimenez, A. C.; Molina, A.;
   Morales, R.; Moreno, F.; Olivares, I.; Rodrigo, R.; Rodriguez-Gomez,
   J. F.; Ruiz-Falco, A.; Sanchez, J.; McDonnell, J. A. M.; Leese, M.;
   Lamy, P.; Perruchot, S.; Crifo, J. F.; Fulle, M.; Perrin, J. M.;
   Angrilli, F.; Coradini, A.; Giovane, F.; Gruen, E.; Gustafson, B.;
   Maag, C.; Weissman, P. R.
1999BAAS...31R1119C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: CME observed continuously from the lower corona to the far
    corona (CME's onset on November 3, 1997).
Authors: Delannée, C.; Delaboudinière, J. -P.; Lamy, P.
1999joso.proc..162D    Altcode:
  A program of observations with EIT on board SOHO, is to observe the
  whole sun surface in 195 Å, i.e. in a Fe XII emission line, every
  17 minutes. The very beginning of some CMEs is observed. The authors
  correlate each Fe XII observation with He II, Hα and coronagraph
  observations on 97/11/03 and 97/11/04. They found that three prominences
  were ejected, and that an active region produced 4 ejections. The
  ejections are dark bubbles propagating above the sun limb, and dimmings
  propagating on the solar surface in Fe XII. They each produced an
  associated CME. One CME was not correlated to a Fe XII low corona
  event. Maybe, this CME had its origin behind the limb. The prominence
  gave a quite slow CME, i.e. about 50 km s<SUP>-1</SUP> and the active
  region produced some quite fast CMEs, i.e. about 300 km s<SUP>-1</SUP>.

---------------------------------------------------------
Title: Hubble Space Telescope observations of the nucleus and inner
    coma of comet 19P/1904 Y2 (Borrelly)
Authors: Lamy, Philippe L.; Toth, Imre; Weaver, Harold A.
1998A&A...337..945L    Altcode:
  The nucleus of comet 19P/Borrelly was detected using the Planetary
  Camera (WFPC2) of the Hubble Space Telescope (HST). During the time
  of our observations, the comet was 0.62 AU from the Earth, 1.40 AU
  from the Sun, and had a solar phase angle of 38°. The high spatial
  resolution of the HST images allowed us to discriminate clearly between
  the signal from the nucleus and that from the coma. The lightcurve
  of the nucleus indicates that it is a highly elongated body rotating
  with a synodic period of 25.0+/-0.5 hr. Assuming that the nucleus has
  a geometric albedo of 4% and is a prolate spheroid with a rotational
  axis pointing in the direction determined by Sekanina (1979), we
  derive that its semi-axes are 4.4+/-0.3 km and 1.8+/-0.15 km. The
  corresponding fractional active area of $() sim$8 {%} suggests a
  moderately active comet. The highly anisotropic coma is dominated by
  a strong sunward fan, and the dust production rate exhibited signs of
  temporal variability throughout our observations. Based on observations
  made with the NASA/ESA Hubble Space Telescope, obtained at the Space
  Telescope Science Institute, which is operated by the Association of
  Universities for Research in Astronomy, under NASA contract NAS 5-26555

---------------------------------------------------------
Title: Joint Nancay Radioheliograph and LASCO Observations of Coronal
    Mass Ejections - II. The 9 July 1996 Event
Authors: Pick, M.; Maia, D.; Kerdraon, A.; Howard, R.; Brueckner,
   G. E.; Michels, D. J.; Paswaters, S.; Schwenn, R.; Lamy, P.; Llebaria,
   A.; Simnett, G.; Lanzerotti, L. J.; Aurass, H.
1998SoPh..181..455P    Altcode:
  The development of a coronal mass ejection on 9 July 1996 has been
  analyzed by comparing the observations of the LASCO/SOHO coronagraphs
  with those of the Nancay radioheliograph. The spatial and temporal
  evolution of the associated radioburst is complex and involves a
  long-duration continuum. The analysis of the time sequence of the
  radio continuum reveals the existence of distinct phases associated
  with distinct reconnection processes and magnetic restructuring
  of the corona. Electrons are accelerated in association with these
  reconnection processes. An excellent spatial association is found
  between the position and extension of the radio source and the CME seen
  by LASCO. Furthermore, it is shown that the topology and evolution
  of the source of the radio continuum involve successive interactions
  between two systems of loops. These successive interactions lead to
  magnetic reconnection, then to a large scale coronal restructuring. Thus
  electrons of coronal origin may have access to the interplanetary
  medium in a large range of heliographic latitudes as revealed by the
  Ulysses observations.

---------------------------------------------------------
Title: Comet 9P/Tempel 1
Authors: Lamy, P.
1998IAUC.7000....3L    Altcode: 1998IAUC.7000C...1L; 1998IAUC.7000S...1L
  P. Lamy, Laboratoire d'Astronomie Spatiale, and his team report the
  detection of the nucleus of comet 9P with the Hubble Space Telescope
  (+ WFPC2) on 1997 Dec. 31 at Delta = 3.53 AU and r = 4.48 AU: "The
  slightly incomplete lightcurve indicates an elongated body having
  semi-axes a = 3.9 and b = 2.8 km (assuming a geometric albedo of 0.04)
  and a rotational period of about 25 hr. No coma was detected."

---------------------------------------------------------
Title: Geomagnetic storms caused by coronal mass ejections (CMEs):
    March 1996 through June 1997
Authors: Brueckner, G. E.; Delaboudiniere, J. -P.; Howard, R. A.;
   Paswaters, S. E.; St. Cyr, O. C.; Schwenn, R.; Lamy, P.; Simnett,
   G. M.; Thompson, B.; Wang, D.
1998GeoRL..25.3019B    Altcode:
  (1) All but two geomagnetic storms with Kp ≥ 6 during the operating
  period (March 1996 through June 1997) of the Large Angle Spectroscopic
  Coronagraph (LASCO) experiment on the Solar and Heliospheric Observatory
  (SOHO) spacecraft can be traced to Coronal Mass Ejections (CMEs). (2)
  These geomagnetic storms are not related to high speed solar wind
  streams. (3) The CMEs which cause geomagnetic effects, can be classified
  into two categories: Halo events and toroidal CMEs. (4) The CMEs are
  accompanied by Coronal Shock Waves as seen in the Extreme Ultraviolet
  Imaging Telescope (EIT) Fe XII images. (5) Some CMEs are related to
  flares, others are not. (6) In many cases, the travel time between
  the explosion on the Sun and the maximum geomagnetic activity is about
  80 hours.

---------------------------------------------------------
Title: The Solar Minimum Active Region 7978, Its X2.6/1B Flare, CME,
    and Interplanetary Shock Propagation of 9 July 1996
Authors: Dryer, M.; Andrews, M. D.; Aurass, H.; DeForest, C.; Galvin,
   A. B.; Garcia, H.; Ipavich, F. M.; Karlický, M.; Kiplinger, A.;
   Klassen, A.; Meisner, R.; Paswaters, S. E.; Smith, Z.; Tappin,
   S. J.; Thompson, B. J.; Watari, S. I.; Michels, D. J.; Brueckner,
   G. E.; Howard, R. A.; Koomen, M. J.; Lamy, P.; Mann, G.; Arzner, K.;
   Schwenn, R.
1998SoPh..181..159D    Altcode:
  The first X-class flare in four years occurred on 9 July 1996. This
  X2.6/1B flare reached its maximum at 09:11 UT and was located in active
  region 7978 (S10° W30°) which was an old-cycle sunspot polarity
  group. We report the SOHO LASCO/EIT/MDI and SOONSPOT observations before
  and after this event together with Yohkoh SXT images of the flare,
  radio observations of the type II shock, and GOES disk-integrated soft
  X-ray flux during an extended period that included energy build-up in
  this active region.

---------------------------------------------------------
Title: The nucleus and inner coma of Comet 46P/Wirtanen
Authors: Lamy, P. L.; Toth, I.; Jorda, L.; Weaver, H. A.; A'Hearn, M.
1998A&A...335L..25L    Altcode:
  We report the detection of the nucleus of comet 46P/Wirtanen from
  analysis of images taken with the Planetary Camera (WFPC2) of the Hubble
  Space Telescope (HST) on 28 August 1996. The high spatial resolution
  (a WFPC2 pixel projects to 50 km at the distance of the comet) allowed
  us to separate the signal of the nucleus from that of the coma and to
  determine the Landolt V and R magnitudes of the nucleus. Assuming a
  spherical body with a geometric albedo of 0.04 and a phase coefficient
  of 0.04 mag/deg, we derived a radius of 0.60+/-0.02 km. The color of the
  nucleus is moderately red with a gradient of 10{%} per 1000 Angstroms at
  optical wavelengths. From the lightcurve data we derived a rotational
  period of 6.0+/-0.3 hr and find that the ratio of the semi-axes of the
  assumed ellipsoidal body must satisfy a/b &gt;= 1.2. From an analysis
  of the dust coma, we derived that Afrho is 23 cm and that the dust
  production rate is 4 kg sec(-1) . Based on observations made with the
  NASA/ESA Hubble Space Telescope, obtained at Space Telescope Science
  Institute, which is operated by the Association of Universities for
  Research in Astronomy under NASA contract NAS 5-26555

---------------------------------------------------------
Title: Joint Nançay Radioheliograph and LASCO Observations of
    Coronal Mass Ejections - I. The 1 July 1996 Event
Authors: Maia, D.; Pick, M.; Kerdraon, A.; Howard, R.; Brueckner,
   G. E.; Michels, D. J.; Paswaters, S.; Schwenn, R.; Lamy, P.; Llebaria,
   A.; Simnett, G.; Aurass, H.
1998SoPh..181..121M    Altcode:
  The development of a coronal mass ejection on 1 July 1996 has been
  analyzed by comparing the observations of the LASCO/SOHO coronagraph
  with those of the Nançay radioheliograph. This comparison brings new
  insight and very useful diagnosis for the study of CME events. It
  is shown that the initial instability took place in a small volume
  located above an active region and that the occurrence of short radio
  type III bursts implies a triggering process due to magnetic field
  interactions. The subsequent spatial and temporal evolution of the
  radio emission strongly suggests that the large scale structure becomes
  unstable within the first minute of the event.

---------------------------------------------------------
Title: LASCO observations of an Earth-directed coronal mass ejection
    on May 12, 1997
Authors: Plunkett, S. P.; Thompson, B. J.; Howard, R. A.; Michels,
   D. J.; St. Cyr, O. C.; Tappin, S. J.; Schwenn, R.; Lamy, P. L.
1998GeoRL..25.2477P    Altcode:
  Coronal mass ejections (CMEs) that occur near the center of the
  solar disk are most likely to impact Earth. Detection of such
  events as ‘halos’ in white-light coronagraphs has been somewhat
  controversial in recent years. We present observations from the LASCO
  coronagraphs on SOHO that provide convincing evidence of the detection
  of an Earth-directed CME on May 12, 1997. The event began at about
  04:35 UT and propagated outwards from the Sun with a projected speed
  of around 250 km s<SUP>-1</SUP>. Using some reasonable assumptions
  about the geometry of the CME, we estimate the true speed to be around
  600 km s<SUP>-1</SUP>. The onset of the event in LASCO is coincident
  (to within measurement uncertainties) with an eruptive event detected
  in extreme ultraviolet observations of the solar disk by the SOHO
  EIT. This is the first reported observation of a halo CME at projected
  distances greater than 10 R<SUB>⊙</SUB>, with a clearly identifiable
  solar origin. We discuss the possibility that at least some of the
  enhanced brightness observed by LASCO may be due to a compressional
  wave propagating in the corona.

---------------------------------------------------------
Title: Space exploration of the outer space solar system and cometary
    nuclei. Proceedings. B0.2 and B0.6 Symposia of COSPAR Scientific
    Commission B held during the Thirty-first COSPAR Scientific Assembly,
    Birmingham (UK), 14 - 21 Jul 1996.
Authors: Matson, D. L.; Thomas, N.; Lamy, P.
1998AdSpR..21.....M    Altcode:
  This is a collection of six papers. Current and planned exploration
  activities for the giant planets, Jupiter and Saturn are discussed. The
  volume starts with an account of the results of the mass spectrometer
  measurements of the Jovian atmosphere. This is a key result from
  the instrumented probe which the Galileo spacecraft delivered to
  Jupiter. Next are results of measurements on the location of the Jovian
  magnetopause and bow shock. Then, several theoretical investigations
  explore effects in the magnetospheres of Jupiter and Saturn. Finally,
  data from the Pioneer and Voyager spacecraft are used to model some
  of the properties of energetic electrons in the Saturnian magnetosphere.

---------------------------------------------------------
Title: Origin of Streamer Material in the Outer Corona
Authors: Wang, Y. -M.; Sheeley, N. R., Jr.; Walters, J. H.; Brueckner,
   G. E.; Howard, R. A.; Michels, D. J.; Lamy, P. L.; Schwenn, R.;
   Simnett, G. M.
1998ApJ...498L.165W    Altcode:
  We investigate the nature and origin of the outward-moving density
  inhomogeneities (“blobs”) detected previously with the Large Angle and
  Spectrometric Coronagraph on the Solar and Heliospheric Observatory. The
  blobs are concentrated around the thin plasma layer that surrounds
  the heliospheric current sheet and that constitutes the outer streamer
  belt; they represent only a small, fluctuating component of the total
  density within the plasma sheet. As noted before in Sheeley et al.,
  blobs are characterized by low speeds and are continually emitted
  from the elongated tips of helmet streamers at 3-4 R<SUB>solar</SUB>
  from Sun center. We suggest that both the blobs and the plasma sheet
  itself represent closed-field material injected into the solar wind as
  a result of footpoint exchanges between the stretched helmet-streamer
  loops and neighboring open field lines. The plasma sheet is thus
  threaded by newly reconnected, open magnetic field lines, which lend
  the white-light streamer belt its filamentary appearance. Since in
  situ observations at 1 AU show that the slow wind (with speeds below
  500 km s<SUP>-1</SUP>) spreads over an angular extent much greater
  than the &lt;~3° width of the plasma sheet, we deduce that a major
  component of this wind must originate outside the helmet streamers
  (i.e., from just inside coronal holes).

---------------------------------------------------------
Title: Comet 55P/Tempel-Tuttle
Authors: Lamy, P.; Znojil, V.; Biver, N.
1998IAUC.6851....2L    Altcode: 1998IAUC.6851R...1L; 1998IAUC.6851B...1L
  P. Lamy, Laboratoire d'Astronomie Spatiale, and his team report the
  detection of the nucleus of comet 55P with the Hubble Space Telescope
  (+ WFPC2) on Jan. 9 at Delta = 0.46 AU: "After removing the faint
  contribution of the coma to the central pixels, the magnitude of
  the nucleus was R = 16.62, showing no variation over 10 hr. For a
  geometric albedo of 0.04 and a phase coefficient of 0.04 mag/deg,
  the mean effective radius is 1.8 km, the largest uncertainty coming
  from the phase law. The red color of the nucleus is characterized
  by a normalized reflectivity gradient of 0.16 percent/nm." Visual
  m_1 estimates: Mar. 1.75 UT, 8.7 (V. Znojil, Brno, Czech R., 25x100
  binoculars); 18.24, 9.7: (N. Biver, Honolulu, HI, 0.26-m reflector).

---------------------------------------------------------
Title: Discrimination of point-like objects in astronomical images
    using surface curvature.
Authors: Llebaria, A.; Lamy, P.; Malburet, P.
1998A&AS..127..587L    Altcode:
  We present a method for the discrimination of point-like objects in
  astronomical images using surface curvature. The principal curvatures
  k_1 and k_2 are calculated using a local quadric approximation to the
  log of the intensity of the original image. The analysis of the (k_1,
  k_2) diagram allows to easily separate various shapes and to establish
  a criterion for discrimination. A mask is then generated and the
  invalid pixels are replaced by a local, pyramidal interpolation using
  a non-linear, multiresolution method. We present two applications,
  the discrimination and removal of stars from the dust tail of comet
  P/Halley observed while it was crossing the Milky Way, and the removal
  of cosmic ray impacts from images of the solar corona obtained with
  a space-coronagraph.

---------------------------------------------------------
Title: Reconstruction of the Electron Density Distribution in the
    Solar Corona Based on LASCO C2 Observations
Authors: Gabryl, J. -R.; Cugnon, P.; Lamy, P.
1998ASPC..155..361G    Altcode: 1998sasp.conf..361G
  No abstract at ADS

---------------------------------------------------------
Title: DFA-the dust flux analyzer for the Rosetta orbiter
Authors: Lamy, P.; Perruchot, S.; Reynaud, J. -L.; Leese, M. R.;
   McDonnell, J. A. M.; Green, S. F.; Busoletti, E.; Colangeli, L.;
   Fulle, M.; Rotundi, A.; Giovane, F.; Gustafson, B.; Perrin, J. -M.
1998AdSpR..21.1557L    Altcode:
  We describe the scientific objectives, the design concept and the
  implementation of the Dust Flux Analyser (DFA) for the ESA Rosetta
  mission. DFA is designed to detect individual dust particles in order
  to study their physical and dynamical properties as a function of
  time and of orbital position, to monitor the spatial distribution
  of the dust production and correlate it with the nucleus emission
  sites and to analyse gas-dust interactions and the evolution of the
  coma. The instrument is composed of three detectors with a common
  electronic box. The Velocity Measurement System (VMS) will measure
  the velocity of the incoming dust particles and the dust detector
  (MOM), its momentum. A separate deposition system (DEP) composed of
  three quartz microbalances will monitor the cometary dust flux in three
  directions. DFA will be able to detect dust particles in the size range
  5-1000 μm and velocity range 0.1-150 m.s^-1. Required resources are
  a mass of 4.9 kg, a power of 3.6 W to 16.7 W and a telemetry of 50 to
  512 kBits per hour depending upon the operating modes.

---------------------------------------------------------
Title: OSIRIS-the optical, spectroscopic and infrared remote imaging
    system for the Rosetta Orbiter
Authors: Thomas, N.; Keller, H. U.; Arijs, E.; Barbieri, C.; Grande,
   M.; Lamy, P.; Rickman, H.; Rodrigo, R.; Wenzel, K. -P.; A'Hearn,
   M. F.; Angrilli, F.; Bailey, M.; Barucci, M. A.; Bertaux, J. -L.;
   Brieß, K.; Burns, J. A.; Cremonese, G.; Curdt, W.; Deceuninck, H.;
   Emery, R.; Festou, M.; Fulle, M.; Ip, W. -H.; Jorda, L.; Korth, A.;
   Koschny, D.; Kramm, J. -R.; Kührt, E.; Lara, L. M.; Llebaria, A.;
   Lopez-Moreno, J. J.; Marzari, F.; Moreau, D.; Muller, C.; Murray,
   C.; Naletto, G.; Nevejans, D.; Ragazzoni, R.; Sabau, L.; Sanz, A.;
   Sivan, J. -P.; Tondello, G.
1998AdSpR..21.1505T    Altcode:
  The scientific objectives, design, and implementation of the Optical,
  Spectroscopic, and Infrared Remote Imaging System (OSIRIS) for the
  International Rosetta Mission are described. The instrument comprises
  two camera systems with a common electronics box. A narrow angle camera
  will provide high resolution images of the structure and morphology
  of the nucleus of a comet. A wide angle camera with high straylight
  rejection and dynamic range will be used to investigate the innermost
  coma and the emission process at the surface of the comet. An infrared
  imaging system, which dramatically enhances the scientific return has
  been included in the narrow angle camera at little extra cost.

---------------------------------------------------------
Title: Time domain analysis of polar plumes observed with LASCO-C2
    and EIT
Authors: Llebaria, A.; Lamy, P.; Deforest, Ce.; Koutchmy, S.
1998ESASP.421...87L    Altcode: 1998sjcp.conf...87L
  No abstract at ADS

---------------------------------------------------------
Title: The panoramic cameras for the Champollion and Roland Cometary
    Surface Science Packages
Authors: Lamy, P.; Bibring, J. -P.; Nguyen-Trong, T.; Soufflot, A.;
   Boit, J. L.; Dohlen, K.
1998AdSpR..21.1581L    Altcode:
  We describe the scientific objectives, the design concept and the
  implementation of the panoramic cameras which are parts of the In-situ
  Imaging System (ISIS) and of the Roland Imaging System (ROLIS) for
  respectively the Champollion and Roland Surface Science Packages of the
  ESA Rosetta mission. Both instruments will characterize the cometary
  surface near the landing site, from the anchoring legs at spatial scales
  not achievable by the orbiter cameras, to the local horizon. ROLIS-P
  will further monitor the cometary activity and the resulting changes in
  the local topography. Both instruments are composed of several identical
  miniaturized cameras incorporating a 1024 x 1024 pixels, frame transfer
  CCD and a wide-angle optics having a field-of-view of 70 deg. ISIS-P
  includes six such cameras to record the full panorama without any
  mechanical rotation plus three additional ones to offer stereoscopic
  capability in three of the six fields-of-view. ROLIS-P takes advantage
  of the rotating capability of the Roland probe and is therefore limited
  to a single pair of (stereo) cameras. The camera heads with associated
  electronics will be integrated in a single module using the technology
  of three-dimensional packaging of electronic components resulting in
  highly compact, extremely lightweight units. Both instruments will
  provide unique information on the cometary surface at a spatial scale
  of 2 mm.

---------------------------------------------------------
Title: Development of Coronal Mass Ejections and Association with
    Interplanetary Events
Authors: Pick, M.; Maia, D.; Howard, R.; Thompson, B.; Lanzerotti,
   L. J. L.; Bothmer, V.; Lamy, P.
1997ESASP.415..195P    Altcode: 1997cpsh.conf..195P
  No abstract at ADS

---------------------------------------------------------
Title: Evidence of an Erupting Magnetic Flux Rope: LASCO Coronal
    Mass Ejection of 1997 April 13
Authors: Chen, J.; Howard, R. A.; Brueckner, G. E.; Santoro, R.;
   Krall, J.; Paswaters, S. E.; St. Cyr, O. C.; Schwenn, R.; Lamy, P.;
   Simnett, G. M.
1997ApJ...490L.191C    Altcode:
  A coronal mass ejection (CME) observed by LASCO exhibits evidence
  that its magnetic field geometry is that of a flux rope. The dynamical
  properties throughout the fields of view of C2 and C3 telescopes are
  examined. The results are compared with theoretical predictions based
  on a model of solar flux ropes. It is shown that the LASCO observations
  are consistent with a two-dimensional projection of a three-dimensional
  magnetic flux rope with legs that remain connected to the Sun.

---------------------------------------------------------
Title: White-Light Coronal Mass Ejections: A New Perspective from
    LASCO
Authors: St. Cyr, O. C.; Howard, R. A.; Simnett, G. M.; Gurman, J. B.;
   Plunkett, S. P.; Sheeley, N. R.; Schwenn, R.; Koomen, M. J.; Brueckner,
   G. E.; Michels, D. J.; Andrews, M.; Biesecker, D. A.; Cook, J.; Dere,
   K. P.; Duffin, R.; Einfalt, E.; Korendyke, C. M.; Lamy, P. L.; Lewis,
   D.; Llebaria, A.; Lyons, M.; Moses, J. D.; Moulton, N. E.; Newmark,
   J.; Paswaters, S. E.; Podlipnik, B.; Rich, N.; Schenk, K. M.; Socker,
   D. G.; Stezelberger, S. T.; Tappin, S. J.; Thompson, B.; Wang, D.
1997ESASP.415..103S    Altcode: 1997cpsh.conf..103S
  No abstract at ADS

---------------------------------------------------------
Title: Circumstellar grains: radiation pressure and temperature
    distribution
Authors: Lamy, P. L.; Perrin, J. -M.
1997A&A...327.1147L    Altcode:
  The ratio beta of the radiation pressure force to the gravitational
  attraction is calculated for circumstellar grains. Eleven stars of
  various spectral type are considered and their spectral flux compiled
  from available data sometimes supplemented by appropriate models. The
  materials composing the grains are a silicate (obsidian), organic
  materials (ice tholin, poly-HCN), graphite and glassy carbon. The
  radius of the grain extends from 0.005 to 25 mu m. beta exceeds 1
  for submicronic grains around the hottest stars with the exception of
  the obsidian grains. As far as the coldest stars are concerned, the
  results are not so clear and depend sharply on the illuminating stars
  as well as the nature of the material of the solid particles. Their
  temperatures are also studied and two examples are given for obsidian
  and graphite grains of radii 0.01, 0.1, 1 and 10 mu m. Our results
  are of interest for thin stellar shells such as exo-zodiacal clouds
  and for the inner region of dense shells where multiple scattering
  effects are not taking place.

---------------------------------------------------------
Title: LASCO Observations of Disconnected Magnetic Structures Out
    to Beyond 28 Solar Radii During Coronal Mass Ejections
Authors: Simnett, G. M.; Tappin, S. J.; Plunkett, S. P.; Bedford,
   D. K.; Eyles, C. J.; St. Cyr, O. C.; Howard, R. A.; Brueckner, G. E.;
   Michels, D. J.; Moses, J. D.; Socker, D.; Dere, K. P.; Korendyke,
   C. M.; Paswaters, S. E.; Wang, D.; Schwenn, R.; Lamy, P.; Llebaria,
   A.; Bout, M. V.
1997SoPh..175..685S    Altcode:
  Two coronal mass ejections have been well observed by the LASCO
  coronagraphs to move out into the interplanetary medium as disconnected
  plasmoids. The first, on July 28, 1996, left the Sun above the west
  limb around 18:00 UT. As it moved out, a bright V-shaped structure
  was visible in the C2 coronagraph which moved into the field-of-view
  of C3 and could be observed out to beyond 28 solar radii. The derived
  average velocity in the plane of the sky was 110 ± 5 km s<SUP>-1</SUP>
  out to 5 solar radii, and above 15 solar radii the velocity was 269
  ± 10 km s<SUP>-1</SUP>. Thus there is evidence of some acceleration
  around 6 solar radii. The second event occurred on November 5, 1996
  and left the west limb around 04:00 UT. The event had an average
  velocity in the plane of the sky of ∼54 km s<SUP>-1</SUP> below
  4 R⊙, and it accelerated rapidly around 5 R⊙ up to 310 ± 10 km
  s<SUP>-1</SUP>. In both events the rising plasmoid is connected back
  to the Sun by a straight, bright ray, which is probably a signature of
  a neutral sheet. In the November event there is evidence for multiple
  plasmoid ejections. The acceleration of the plasmoids around a projected
  altitude of 5 solar radii is probably a manifestation of the source
  surface of the solar wind.

---------------------------------------------------------
Title: First View of the Extended Green-Line Emission Corona At
    Solar Activity Minimum Using the Lasco-C1 Coronagraph on SOHO
Authors: Schwenn, R.; Inhester, B.; Plunkett, S. P.; Epple, A.;
   Podlipnik, B.; Bedford, D. K.; Eyles, C. J.; Simnett, G. M.; Tappin,
   S. J.; Bout, M. V.; Lamy, P. L.; Llebaria, A.; Brueckner, G. E.;
   Dere, K. P.; Howard, R. A.; Koomen, M. J.; Korendyke, C. M.; Michels,
   D. J.; Moses, J. D.; Moulton, N. E.; Paswaters, S. E.; Socker, D. G.;
   St. Cyr, O. C.; Wang, D.
1997SoPh..175..667S    Altcode:
  The newly developed C1 coronagraph as part of the Large-Angle
  Spectroscopic Coronagraph (LASCO) on board the SOHO spacecraft has
  been operating since January 29, 1996. We present observations
  obtained in the first three months of operation. The green-line
  emission corona can be made visible throughout the instrument's full
  field of view, i.e., from 1.1 R⊙ out to 3.2 R⊙ (measured from Sun
  center). Quantitative evaluations based on calibrations cannot yet be
  performed, but some basic signatures show up even now: (1) There are
  often bright and apparently closed loop systems centered at latitudes
  of 30° to 45° in both hemispheres. Their helmet-like extensions
  are bent towards the equatorial plane. Farther out, they merge into
  one large equatorial `streamer sheet' clearly discernible out to 32
  R⊙. (2) At mid latitudes a more diffuse pattern is usually visible,
  well separated from the high-latitude loops and with very pronounced
  variability. (3) All high-latitude structures remain stable on time
  scales of several days, and no signature of transient disruption of
  high-latitude streamers was observed in these early data. (4) Within
  the first 4 months of observation, only one single `fast' feature was
  observed moving outward at a speed of 70 km s<SUP>-1</SUP> close to
  the equator. Faster events may have escaped attention because of data
  gaps. (5) The centers of high-latitude loops are usually found at the
  positions of magnetic neutral lines in photospheric magnetograms. The
  large-scale streamer structure follows the magnetic pattern fairly
  precisely. Based on our observations we conclude that the shape
  and stability of the heliospheric current sheet at solar activity
  minimum are probably due to high-latitude streamers rather than to
  the near-equatorial activity belt.

---------------------------------------------------------
Title: The Relationship of Green-Line Transients to White-Light
    Coronal Mass Ejections
Authors: Plunkett, S. P.; Brueckner, G. E.; Dere, K. P.; Howard,
   R. A.; Koomen, M. J.; Korendyke, C. M.; Michels, D. J.; Moses, J. D.;
   Moulton, N. E.; Paswaters, S. E.; St. Cyr, O. C.; Socker, D. G.;
   Wang, D.; Simnett, G. M.; Bedford, D. K.; Biesecker, D. A.; Eyles,
   C. J.; Tappin, S. J.; Schwenn, R.; Lamy, P. L.; Llebaria, A.
1997SoPh..175..699P    Altcode:
  We report observations by the Large Angle Spectrometric Coronagraph
  (LASCO) on the SOHO spacecraft of three coronal green-line transients
  that could be clearly associated with coronal mass ejections (CMEs)
  detected in Thomson-scattered white light. Two of these events, with
  speeds &gt;25 km s<SUP>-1</SUP>, may be classified as `whip-like'
  transients. They are associated with the core of the white-light
  CMEs, identified with erupting prominence material, rather than with
  the leading edge of the CMEs. The third green-line transient has a
  markedly different appearance and is more gradual than the other two,
  with a projected outward speed &lt;10 km s<SUP>-1</SUP>. This event
  corresponds to the leading edge of a `streamer blowout' type of CME. A
  dark void is left behind in the emission-line corona following each of
  the fast eruptions. Both fast emission-line transients start off as a
  loop structure rising up from close to the solar surface. We suggest
  that the driving mechanism for these events may be the emergence of new
  bipolar magnetic regions on the surface of the Sun, which destabilize
  the ambient corona and cause an eruption. The possible relationship of
  these events to recent X-ray observations of CMEs is briefly discussed.

---------------------------------------------------------
Title: MHD Interpretation of LASCO Observations of a Coronal Mass
    Ejection as a Disconnected Magnetic Structure
Authors: Wu, S. T.; Guo, W. P.; Andrews, M. D.; Brueckner, G. E.;
   Howard, R. A.; Koomen, M. J.; Korendyke, C. M.; Michels, D. J.; Moses,
   J. D.; Socker, D. G.; Dere, K. P.; Lamy, P. L.; Llebaria, A.; Bout,
   M. V.; Schwenn, R.; Simnett, G. M.; Bedford, D. K.; Eyles, C. J.
1997SoPh..175..719W    Altcode:
  We present a qualitative and quantitative comparison of a single
  coronal mass ejection (CME) as observed by LASCO (July 28-29, 1996)
  with the results of a three-dimensional axisymmetric time-dependent
  magnetohydrodynamic model of a flux rope interacting with a helmet
  streamer. The particular CME considered was selected based on the
  appearance of a distinct `tear-drop' shape visible in animations
  generated from both the data and the model.

---------------------------------------------------------
Title: EIT and LASCO Observations of the Initiation of a Coronal
    Mass Ejection
Authors: Dere, K. P.; Brueckner, G. E.; Howard, R. A.; Koomen, M. J.;
   Korendyke, C. M.; Kreplin, R. W.; Michels, D. J.; Moses, J. D.;
   Moulton, N. E.; Socker, D. G.; St. Cyr, O. C.; Delaboudinière, J. P.;
   Artzner, G. E.; Brunaud, J.; Gabriel, A. H.; Hochedez, J. F.; Millier,
   F.; Song, X. Y.; Chauvineau, J. P.; Marioge, J. P.; Defise, J. M.;
   Jamar, C.; Rochus, P.; Catura, R. C.; Lemen, J. R.; Gurman, J. B.;
   Neupert, W.; Clette, F.; Cugnon, P.; Van Dessel, E. L.; Lamy, P. L.;
   Llebaria, A.; Schwenn, R.; Simnett, G. M.
1997SoPh..175..601D    Altcode:
  We present the first observations of the initiation of a coronal mass
  ejection (CME) seen on the disk of the Sun. Observations with the EIT
  experiment on SOHO show that the CME began in a small volume and was
  initially associated with slow motions of prominence material and a
  small brightening at one end of the prominence. Shortly afterward,
  the prominence was accelerated to about 100 km s<SUP>-1</SUP> and
  was preceded by a bright loop-like structure, which surrounded an
  emission void, that traveled out into the corona at a velocity of
  200-400 km s<SUP>-1</SUP>. These three components, the prominence,
  the dark void, and the bright loops are typical of CMEs when seen at
  distance in the corona and here are shown to be present at the earliest
  stages of the CME. The event was later observed to traverse the LASCO
  coronagraphs fields of view from 1.1 to 30 R⊙. Of particular interest
  is the fact that this large-scale event, spanning as much as 70 deg in
  latitude, originated in a volume with dimensions of roughly 35" (2.5
  x 10<SUP>4</SUP> km). Further, a disturbance that propagated across
  the disk and a chain of activity near the limb may also be associated
  with this event as well as a considerable degree of activity near the
  west limb.

---------------------------------------------------------
Title: Estimating the Size of Hale-Bopp's Nucleus
Authors: Weaver, H. A.; Lamy, P. L.
1997EM&P...79...17W    Altcode:
  A variety of independent methods have been used to estimate the size of
  the nucleus of comet Hale-Bopp. Several groups have analyzed optical
  and infrared images of the comet and claim to detect the signature of
  the nucleus, despite the presence of a strong coma. A detection of
  the nucleus was also claimed during mm- and cm-wave observations of
  Hale-Bopp shortly before perihelion. A team of observers detected the
  occultation of a star by the nucleus of Hale-Bopp in October 1996. The
  maximum observed gas production rate of the comet near perihelion can
  be used to place a lower limit on the size of the nucleus. This paper
  critically reviews the many different methods used to constrain the size
  of Hale-Bopp's nucleus. All of the techniques are affected by systematic
  errors that can be difficult to quantify precisely. Nevertheless, the
  available evidence strongly suggests that the nucleus of Hale-Bopp has
  an effective radius of at least 15 km and is probably in the range 20
  35 km. Thus, the prodigious gas and production rates from this comet
  are naturally explained by its unusually large size.

---------------------------------------------------------
Title: Origin and Evolution of Coronal Streamer Structure During
    the 1996 Minimum Activity Phase
Authors: Wang, Y. -M.; Sheeley, N. R., Jr.; Howard, R. A.; Kraemer,
   J. R.; Rich, N. B.; Andrews, M. D.; Brueckner, G. E.; Dere, K. P.;
   Koomen, M. J.; Korendyke, C. M.; Michels, D. J.; Moses, J. D.;
   Paswaters, S. E.; Socker, D. G.; Wang, D.; Lamy, P. L.; Llebaria,
   A.; Vibert, D.; Schwenn, R.; Simnett, G. M.
1997ApJ...485..875W    Altcode:
  We employ coronal extrapolations of solar magnetograph data to interpret
  observations of the white-light streamer structure made with the LASCO
  coronagraph in 1996. The topological appearance of the streamer belt
  during the present minimum activity phase is well described by a model
  in which the Thomson-scattering electrons are concentrated around a
  single, warped current sheet encircling the Sun. Projection effects
  give rise to bright, jet-like structures or spikes whenever the current
  sheet is viewed edge-on multiple spikes are seen if the current sheet is
  sufficiently wavy. The extreme narrowness of these features in polarized
  images indicates that the scattering layer is at most a few degrees
  wide. We model the evolution of the streamer belt from 1996 April to
  1996 September and show that the effect of photospheric activity on
  the streamer belt topology depends not just on the strength of the
  erupted magnetic flux, but also on its longitudinal phase relative
  to the background field. Using flux transport simulations, we also
  demonstrate how the streamer belt would evolve during a prolonged
  absence of activity.

---------------------------------------------------------
Title: Measurements of Flow Speeds in the Corona Between 2 and 30
    R<SUB>⊙</SUB>
Authors: Sheeley, N. R.; Wang, Y. -M.; Hawley, S. H.; Brueckner,
   G. E.; Dere, K. P.; Howard, R. A.; Koomen, M. J.; Korendyke, C. M.;
   Michels, D. J.; Paswaters, S. E.; Socker, D. G.; St. Cyr, O. C.;
   Wang, D.; Lamy, P. L.; Llebaria, A.; Schwenn, R.; Simnett, G. M.;
   Plunkett, S.; Biesecker, D. A.
1997ApJ...484..472S    Altcode:
  Time-lapse sequences of white-light images, obtained during sunspot
  minimum conditions in 1996 by the Large Angle Spectrometric Coronagraph
  on the Solar and Heliospheric Observatory, give the impression of
  a continuous outflow of material in the streamer belt, as if we
  were observing Thomson scattering from inhomogeneities in the solar
  wind. Pursuing this idea, we have tracked the birth and outflow of
  50-100 of the most prominent moving coronal features and find that:
  <P />1. They originate about 3-4 R<SUB>⊙</SUB> from Sun center as
  radially elongated structures above the cusps of helmet streamers. Their
  initial sizes are about 1 R<SUB>⊙</SUB> in the radial direction and
  0.1 R<SUB>⊙</SUB> in the transverse direction. <P />2. They move
  radially outward, maintaining constant angular spans and increasing
  their lengths in rough accord with their speeds, which typically
  double from 150 km s<SUP>-1</SUP> near 5 R<SUB>⊙</SUB> to 300 km
  s<SUP>-1</SUP> near 25 R<SUB>⊙</SUB>. <P />3. Their individual speed
  profiles v(r) cluster around a nearly parabolic path characterized
  by a constant acceleration of about 4 m s<SUP>-2</SUP> through most
  of the 30 R<SUB>⊙</SUB> field of view. This profile is consistent
  with an isothermal solar wind expansion at a temperature of about
  1.1 MK and a sonic point near 5 R<SUB>⊙</SUB>. <P />Based on their
  relatively small initial sizes, low intensities, radial motions, slow
  but increasing speeds, and location in the streamer belt, we conclude
  that these moving features are passively tracing the outflow of the
  slow solar wind.

---------------------------------------------------------
Title: Using LASCO Observations to Infer Solar Wind Flow Near the Sun
Authors: Sheeley, N. R., Jr.; Brueckner, G. E.; Dere, K. P.; Howard,
   R. A.; Korendyke, C. M.; Michels, D. J.; Socker, D. G.; Koomen, M. J.;
   Paswaters, S. E.; Wang, D.; Lamy, P. L.; Llebaria, A.; Schwenn, R.;
   St Cyr, O. C.; Simnett, G. M.; Plunkett, S.; Biesecker, D. A.
1997SPD....28.0301S    Altcode: 1997BAAS...29..907S
  We have continued to track individual coronal features as they become
  detached from helmet streamers and move outward from the Sun. The
  composite speed profile for 50-100 features has a parabolic shape
  with a constant acceleration of about 4 m/s(2) over the 2-30 R field
  of view. This well-determined speed profile contrasts strongly with
  the nearly uniform scatterplot obtained for about 50 nominal coronal
  mass ejections (CMEs), and suggests that these detached bits of coronal
  “debris” are passively tracing the speed of the slow solar wind. We
  have also begun the more difficult task of tracking outflow along
  polar plumes and will summarize these results as of June 1997.

---------------------------------------------------------
Title: The Solar Minimum X2. 6/1B Flare and CME of 9 July 1996;
Part 1: Solar Data
Authors: Andrews, M. D.; Dryer, M.; Aurass, H.; DeForest, C.;
   Kiplinger, A. L.; Meisner, R.; Paswaters, S. E.; Smith, Z.; Tappipn,
   S. J.; Thompson, B. J.; Watari, S. I.; Lamy, P.; Mann, G.; Schwenn,
   R.; Michels, D. J.; Brueckner, G. E.; Howard, R. A.; Koomen, M.
1997ESASP.404..169A    Altcode: 1997cswn.conf..169A
  No abstract at ADS

---------------------------------------------------------
Title: Intercomparison between UVCS/WLC and LASCO/C2 measured
    polarized brightness
Authors: Romoli, M.; Biesecker, D.; Benna, C.; Fineschi, S.; Lamy,
   P. L.; Llebaria, A.; Kohl, J. L.; Noci, G.
1997ESASP.404..637R    Altcode: 1997cswn.conf..637R
  No abstract at ADS

---------------------------------------------------------
Title: Characterisation of Polar Plumes from LASCO-C2 Images in
    Early 1996
Authors: Lamy, P.; Liebaria, A.; Koutchmy, S.; Reynet, P.; Molodensky,
   M.; Howard, R.; Schwenn, R.; Simnett, G.
1997ESASP.404..487L    Altcode: 1997cswn.conf..487L
  No abstract at ADS

---------------------------------------------------------
Title: The April 7, 1997 Event: LASCO and Nancay Radioheliograph
    Joint Observations
Authors: Maia, D.; Pick, M.; Howard, R.; Brueckner, G. E.; Lamy, P.
1997ESASP.404..539M    Altcode: 1997cswn.conf..539M
  No abstract at ADS

---------------------------------------------------------
Title: The Solar Minimum X2. 6/1B Flare and CME of 9 July 1996;
Part 2: Propagation
Authors: Dryer, M.; Andrews, M. D.; Aurass, H.; DeForest, C.; Karlicky,
   M.; Kiplinger, A.; Klassen, A.; Meisner, R.; Ipavich, F. M.; Galvin,
   A. B.; Paswaters, S. E.; Smith, Z.; Tappin, S. J.; Thompson, B. J.;
   Watari, S. -I.; Michels, D. J.; Brueckner, G. E.; Howard, R. A.;
   Koomen, M. J.; Lamy, P.; Mann, G.; Arzner, K.; Schwenn, R.
1997ESASP.404..331D    Altcode: 1997cswn.conf..331D
  No abstract at ADS

---------------------------------------------------------
Title: Acceleration of Coronal Mass Ejections in the Upper Corona:
    Observations from Lasco/Soho
Authors: Simnett, G. M.; Tappin, S. J.; Brueckner, G. E.; Howard,
   R. A.; Lamy, P.; Michels, D. J.; Schwenn, R.
1997ICRC....1..181S    Altcode: 1997ICRC...25a.181S
  No abstract at ADS

---------------------------------------------------------
Title: Dynamical Evolution of a Coronal Mass Ejection (CME) to
Magnetic Cloud: A Preliminary Analysis of the January 6-10, 1997
    CME Observed by LASCO/SOHO
Authors: Wu, S. T.; Guo, W. P.; Michels, D. J.; Andrews, M. D.;
   Brueckner, G. E.; Howard, R. A.; Koomen, M. J.; Korendyke, C. M.;
   Moses, J. D.; Socker, D. G.; Dere, K. P.; Bougeret, Jean-Louis; Lamy,
   P. L.; Schwenn, R.; Simnett, G. M.
1997ESASP.404..739W    Altcode: 1997cswn.conf..739W
  No abstract at ADS

---------------------------------------------------------
Title: In-Orbit Calibration of the Distortion of the SOHO/LASCO-C2
    Coronagraph
Authors: Llebaria, A.; Aubert, S.; Lamy, P.; Plunkett, S.
1997ASPC..125..435L    Altcode: 1997adass...6..435L
  This paper describes distortion calibration procedures for the
  SOHO/LASCO-C2 Coronagraph, based on in-orbit data and extensive image
  processing methods. It addresses specific problems of externally
  occulted coronagraphs (obstructed center of field-of-view, strong
  vignetting, and presence of stray light) and limitations inherent
  to space-based instrumentation (cosmic rays and limited number of
  reference points).

---------------------------------------------------------
Title: EIT and LASCO Observations of the Initiation of a Coronal
    Mass Ejection
Authors: Dere, K. P.; Brueckner, G. E.; Howard, R. A.; Koomen, M. J.;
   Korendyke, C. M.; Michels, D. J.; Moses, J. D.; Moulton, N. E.; Socker,
   D. G.; Delaboudiniere, J. P.; Hochedez, J. F.; Lamy, P. L.; Schwenn,
   R.; Simnett, G. M.; Defise, J. M.; Catura, R. C.
1997IAUJD..19E..18D    Altcode:
  We present the first observations of the initiation of a corona mass
  ejection (CME) seen on the disk of the Sun. Observations with the EIT
  and LASCO experiments on SOHO show that the CME starts in a small volume
  and is associated with slow motions of prominence material. At about
  the same time, a shock wave is created that travels out into the corona
  at a velocity of 400 km s^{-1} ahead of an eruptive prominence. This
  shock wave is clearly the event that is later seen as a classical CME
  when observed in the coronagraph above 1.5 solar radii. Although the
  CME clearly starts in a small region, a chain of activity near the
  limb may also be associated with this event.

---------------------------------------------------------
Title: The Streamer Belt at Solar Minimum: Simulation and Comparison
    with LASCO-C2 Images
Authors: Vibert, D.; Lamy, P.; Liebaria, A.
1997ESASP.404..713V    Altcode: 1997cswn.conf..713V
  No abstract at ADS

---------------------------------------------------------
Title: Reconstruction of the electron density distribution in the
    solar corona based on LASCO C2 observations
Authors: Cugnon, P.; Gabryl, J. -R.; Lamy, P.
1997IAUJD..19E..17C    Altcode:
  From total intensities images provided by the C2 coronagraph with orange
  filter (visible range) we try to reconstruct the large scale electron
  density in the corona, using a model based on the assumption of an
  axisymmetric corona, which allows for a separation between the angular
  and radial descriptions. This method has been successfully applied to
  the eclipse observations of 1991 and 1994 and gave results up to 3.1
  solar radii. In the case of LASCO C2, the range extends from 2.5 to
  7 solar radii, where the F-corona gets more and more predominant. In
  order to extract the K-corona signal, accurate values of the F-corona
  must be subtracted from total intensities. An iterative process based
  on pre-existing tables is applied for this purpose. We also trace the
  evolution of the global structure of the corona during a solar rotation.

---------------------------------------------------------
Title: Electronic Densities in Coronal Holes from LASCO-C2 Images
Authors: Lamy, P.; Quemerais, E.; Llebaria, A.; Bout, M.; Howard,
   R.; Schwenn, R.; Simnett, G.
1997ESASP.404..491L    Altcode: 1997cswn.conf..491L
  No abstract at ADS

---------------------------------------------------------
Title: Joint Radioheliograph and LASCO Observations of Coronal
    Mass Ejections
Authors: Pick, M.; Maia, D.; Howard, R.; Kerdraon, A.; Brueckner,
   G. E.; Lamy, P.; Schwenn, R.; Aurass, H.
1997ESASP.404..601P    Altcode: 1997cswn.conf..601P
  No abstract at ADS

---------------------------------------------------------
Title: Visibility of Earth-Directed Coronal Mass Ejections
Authors: Michels, D. J.; Howard, R. A.; Koomen, M. J.; Plunkett, S.;
   Brueckner, G. E.; Lamy, Ph.; Schwenn, R.; Biesecker, D. A.
1997ESASP.404..567M    Altcode: 1997cswn.conf..567M
  No abstract at ADS

---------------------------------------------------------
Title: Analysis of a High Latitude Slow CME with Travelling Ejecta
Authors: Boulade, S.; Delanné, C.; Koutchmy, S.; Lamy, P.; Llebaria,
   A.; Howard, R.; Schwenn, R.; Simnett, G.
1997ESASP.404..217B    Altcode: 1997cswn.conf..217B
  No abstract at ADS

---------------------------------------------------------
Title: Synthetic Images of the Solar Corona from Octree Representation
    of 3-D Electron Distributions
Authors: Vibert, D.; Llebaria, A.; Netter, T.; Balard, L.; Lamy, P.
1997ASPC..125..230V    Altcode: 1997adass...6..230V
  Empirical and theoretical modeling of 3-D structures in the solar corona
  is confronted by the tremendous amount of data needed to represent
  phenomena with a large dynamic range both in size and magnitude,
  and with a rapid temporal evolution. Octree representation of the
  3-D coronal electron distribution offers the right compromise between
  resolution and size, allowing computation of synthetic images of the
  solar corona.

---------------------------------------------------------
Title: The infrared spectrum of comet C/1995 O1 (Hale-Bopp) at 4.6
    AU from the Sun.
Authors: Crovisier, J.; Brooke, T. Y.; Hanner, M. S.; Keller, H. U.;
   Lamy, P. L.; Altieri, B.; Bockelee-Morvan, D.; Jorda, L.; Leech, K.;
   Lellouch, E.
1996A&A...315L.385C    Altcode:
  Comet C/1995 O1 (Hale-Bopp) was observed on 27 April 1996 with the
  ISOPHOT instrument of ISO when it was at 4.6 AU from the Sun. The
  2.5-12μm spectrum was recorded at low resolution. We present here
  the preliminary results of this observation. The 2.5-5μm spectrum
  shows emission in the CO_2_ ν_3_ band. The CO_2_ production rate is
  about 1.3x10^28^ s^-1^. The 6-12μm spectrum shows thermal emission
  at a colour temperature of 162K (6-8μm range) and a strong silicate
  band around 10μm, with a narrow feature at 11.2μm indicative of
  crystalline silicates.

---------------------------------------------------------
Title: STEREO: a solar terrestrial event observer mission concept
Authors: Socker, Dennis G.; Antiochos, S. K.; Brueckner, Guenter E.;
   Cook, John W.; Dere, Kenneth P.; Howard, Russell A.; Karpen, J. T.;
   Klimchuk, J. A.; Korendyke, Clarence M.; Michels, Donald J.; Moses,
   J. Daniel; Prinz, Dianne K.; Sheely, N. R.; Wu, Shi T.; Buffington,
   Andrew; Jackson, Bernard V.; Labonte, Barry; Lamy, Philippe L.;
   Rosenbauer, H.; Schwenn, Rainer; Burlaga, L.; Davila, Joseph M.; Davis,
   John M.; Goldstein, Barry; Harris, H.; Liewer, Paulett C.; Neugebauer,
   Marcia; Hildner, E.; Pizzo, Victor J.; Moulton, Norman E.; Linker,
   J. A.; Mikic, Z.
1996SPIE.2804...50S    Altcode:
  A STEREO mission concept requiring only a single new spacecraft has been
  proposed. The mission would place the new spacecraft in a heliocentric
  orbit and well off the Sun- Earth line, where it can simultaneously view
  both the solar source of heliospheric disturbances and their propagation
  through the heliosphere all the way to the earth. Joint observations,
  utilizing the new spacecraft and existing solar spacecraft in earth
  orbit or L1 orbit would provide a stereographic data set. The new
  and unique aspect of this mission lies in the vantage point of the
  new spacecraft, which is far enough from Sun-Earth line to allow an
  entirely new way of studying the structure of the solar corona, the
  heliosphere and solar-terrestrial interactions. The mission science
  objectives have been selected to take maximum advantage of this new
  vantage point. They fall into two classes: those possible with the
  new spacecraft alone and those possible with joint measurements using
  the new and existing spacecraft. The instrument complement on the new
  spacecraft supporting the mission science objectives includes a soft
  x-ray imager, a coronagraph and a sun-earth imager. Telemetry rate
  appears to be the main performance determinant. The spacecraft could
  be launched with the new Med-Lite system.

---------------------------------------------------------
Title: Spectroscopic Observations of Comet C/1995 O1 (Hale-Bopp)
    with the Infrared Space Observatory
Authors: Crovisier, J.; Bockelee-Morvan, D.; Lellouch, E.; Brooke,
   T. Y.; Hanner, M. S.; Keller, H. U.; Jorda, L.; Altieri, B.; Leech,
   K.; Lamy, P. L.
1996DPS....28.0921C    Altcode: 1996BAAS...28.1092C
  Comet C/1995 O1 (Hale-Bopp) was selected to be observed in the
  target-of-opportunity comet program of the Infrared Space Observatory
  (ISO). The first results of the spectroscopic part of this program
  are reported here. Comet Hale-Bopp was observed on 27 April 1996 with
  the ISOPHOT instrument of ISO when it was at 4.6 AU from the Sun. The
  2.5--12 mu m spectrum was recorded at low resolution. The 2.5--5. mu m
  spectrum shows emission in the CO_2 nu_3 band at 4.26 mu m. Upper limits
  for other molecular bands (H_2O, CO, CH_3OH) are in agreement with
  observations of these species at other wavelengths. The CO_2 production
  rate is about 1.3 x 10(28) molecules s(-1) . This is about one third of
  the H_2O and CO production rates observed at other wavelengths, which
  indicates that carbon dioxide is an important constituant of cometary
  volatiles at this heliocentric distance. The 6--12 mu m spectrum shows
  thermal emission at a colour temperature of 162 K (6--8 mu m range)
  and a strong silicate band around 10 mu m, with a narrow feature at
  11.2 mu m indicative of crystalline silicates. There is no indication
  of differences of composition for grains in comets Hale-Bopp and
  Halley. Comet Hale-Bopp is to be observed at higher spectral resolution
  with the SWS and LWS instruments of ISO in September-October 1996.

---------------------------------------------------------
Title: Comet 46P/Wirtanen
Authors: Lamy, P.
1996IAUC.6478....2L    Altcode:
  P. Lamy, Laboratoire d'Astronomie Spatiale, and his team report the
  apparent detection of the nucleus of 46P with the Hubble Space Telescope
  (+ WFPC2) on Aug. 28: "After removing the small contribution of the
  (stable) coma to the central pixels, the R magnitude of the nucleus
  was found to vary from 21.6 to 21.9 over time intervals of 1.5 hr,
  though a clear rotational pattern is not evident. For a geometric
  albedo of 0.04, the mean effective radius is 0.58 km."

---------------------------------------------------------
Title: HST Observations of the Nuclei of Comets
    45P/Honda-Mrkos-Pajdusakova, 22P/Kopff, and 46P/Wirtanen
Authors: Lamy, P. L.; A'Hearn, M. F.; Toth, I.; Weaver, H. A.
1996DPS....28.0804L    Altcode: 1996BAAS...28.1083L
  Comet 45P/Honda-Mrkos-Pajdusakova (H-M-P) was observed with
  the Planetary Camera (WFPC2) of the Hubble Space Telescope on
  two consecutive days, 4 and 5 February 1996, at which time the
  geocentric distance was 0.17 AU (1 pixel projected to a distance
  of 5.6 km at the comet) and the phase angles were 93 and 88 deg,
  respectively. Although much fainter than expected, the nucleus was
  clearly detected superimposed on a very weak coma. The accuracy of
  the determination of the size of the nucleus is limited primarily
  by the unknown phase law for such large phase angles. Assuming a
  constant phase coefficient of 0.04 mag/deg and a geometric albedo of
  0.04 near 675 nm, we derived an effective diameter of 0.70 km. Comet
  22P/Kopff was observed on 18 July 1996 at a geocentric distance of
  0.57 AU (1 pixel projected to a distance of 19 km at the comet) and
  a phase angle of 3 deg. Over the 11 hour time interval spanned by
  the observations, we see a variation in the nuclear magnitude that
  corresponds to changes in the effective nuclear diameter from 3.30 to
  3.84 km, using the same assumptions as above for the albedo and phase
  law. The uncertainty in the nuclear diameter is determined primarily
  by the systematic error in estimating the contribution of the coma
  to the peak pixel intensity. The light curve data are being used
  to determine the rotation period for the nucleus. Comparison of our
  derived sizes with published gas production rates for comets H-M-P and
  Kopff indicate that the fractional active surface area is ~ 10% for
  each nucleus. Comet 46P/Wirtanen will be observed on 28 August 1996,
  and we expect to report preliminary results on its size.

---------------------------------------------------------
Title: LASCO Observations of the 03Feb96 Streamer Blow-out
Authors: Andrews, M. D.; Korendyke, C. M.; Koomen, M. J.; Brueckner,
   G. E.; Cook, J. W.; Dere, K. P.; Howard, R. A.; Michels, D. J.; Moses,
   J. D.; Morrill, J. S.; Moulton, N. E.; Paswaters, S. E.; Socker, D. G.;
   St. Cyr, O. C. St.; Wang, D.; Lamy, P. L.; Llebaria, A.; Bout, M. V.;
   Schwenn, R.; Podlipnik, B.; Bedford, D. K.; Biesecker, D. A.; Eyles,
   C. J.; Plunkett, S.; Simnett, G. M.
1996AAS...188.3716A    Altcode: 1996BAAS...28..880A
  The C2 and C3 telescopes on the Large Angle Spectrometric Coronograph
  (LASCO) have recorded images of a Streamer Blow-out which occured
  on 03Feb96. We will present a series of images produces by combining
  data from the 2 coronographs. These images show a rapid evolution of
  the coronal streamer belt over projected distances of 2 to 20 solar
  radii. The streamer belt shows a dramatic brightening, which is seen to
  propagate outward. A bubble-like structure is seen to move away from
  the Sun and expand. At the end of this event, the equatorial corona
  is significantly less bright than prior to the event.

---------------------------------------------------------
Title: LASCO Observations of the Solar Corona to 32 R<SUB>sun</SUB>
Authors: Cook, J. W.; Koomen, M. J.; Korendyke, C. M.; Brueckner,
   G. E.; Dere, K. P.; Howard, R. A.; Michels, D. J.; Morrill, J. S.;
   Moses, J. D.; Socker, D. G.; Paswaters, S. E.; Wang, D.; Moulton,
   N. E.; Cyr, O. C. St.; Andrews, M. D.; Schwenn, R.; Podlipnik, B.;
   Lamy, P. L.; Llebaria, A.; Bout, M. V.; Simnett, G. M.; Bedford,
   D. K.; Eyles, C. J.; Plunkett, S.; Biesecker, D. A.
1996AAS...188.3717C    Altcode: 1996BAAS...28..880C
  The Large Angle Spectrometric Coronagraph (LASCO) was launched on
  board the SOHO satellite on 2 December 1995. The C3 externally-occulted
  coronagraph of LASCO observes the solar corona over a field from 3.7-32
  R_ ⊙, using a 1024x1024 CCD detector with a pixel size corresponding
  to 56 arc sec. Observations can be made using color filters ranging
  from the blue (420-520 nm) to the near-IR (860-1050 nm), and through
  polarizing filters. We report on early observations of the solar corona
  out to 32 R<SUB>sun</SUB>.

---------------------------------------------------------
Title: Preliminary Photometric Calibration of LASCO C3 Coronagraph
    Images using Pre-Flight Laboratory Images of Standard Sources and
    In-Flight Images of Standard Stars
Authors: Korendyke, C. M.; Koomen, M. J.; Andrews, M. D.; Brueckner,
   G. E.; Cook, J. W.; Dere, K. P.; Howard, R. A.; Michels, D. J.;
   Moses, J. D.; Morrill, J. S.; Moulton, N. E.; Paswaters, S. E.;
   Socker, D. G.; St. Cyr, O. C.; Wang, D.; Lamy, P. L.; Llebaria, A.;
   Bout, M. V.; Schwenn, R.; Podlipnik, B.; Bedford, D. K.; Biesecker,
   D. A.; Eyles, C. J.; Plunkett, S.; Simnett, G. M.
1996AAS...188.3621K    Altcode: 1996BAAS...28..876K
  The C3 coronagraph is a wide field (+/-8.0 degrees), externally
  occulted, white light coronagraph. The instrument is one of three
  coronagraphs comprising the Large Angle Spectrometric COronagraph
  (LASCO) experiment mounted on the Solar Heliospheric Observatory
  satellite. The satellite was launched on Dec. 2, 1996; C3 observations
  began in early Jan. 1997. The coronagraph optical train includes a set
  of five broadband color filters mounted in a wheel. Prior to flight,
  an image was obtained through each color filter of a well characterized,
  rear-illuminated, opal glass diffusing screen. The C3 in-flight images,
  in addition to the coronal structures, also contain several hundred
  bright stars. We present a comparison of the photometric calibration
  derived from standard stars with the laboratory measurements. The
  resulting calibration is then used to examine color variations in the
  white light corona over the field of view. The LASCO experiment was
  developed by a scientific consortium of members from NRL (USA), MPAe
  (Germany), LAS (France) and U. Birmingham (United Kingdom).

---------------------------------------------------------
Title: Optical designs for the Rosetta narrow-angle camera
Authors: Dohlen, Kjetil; Saisse, Michel; Claeysen, Genevieve; Lamy,
   Philippe L.; Boit, Jean-Lucien
1996OptEn..35.1150D    Altcode:
  Optical designs for the Rosetta narrow-angle camera (NAC) and its UV
  spectrograph are presented. The NAC requires a 600 mm focal length
  system of focal ratio f/7 imaging a square field of width 2.3 deg onto
  a square detector array 2048 pixels wide. A cartographic method has
  been used to search for flat-field, three-mirror anastigmats (TMA)
  with the required geometrical constraints and at least one spherical
  surface; the use of spherical surfaces reduces fabrication cost and
  complexity and facilitates alignment. Two such systems are described,
  one with a spherical secondary, the other with a spherical tertiary. A
  deterministic alignment method is outlined where alignment defects are
  calculated from measurements of image position and Zernike wavefront
  coefficients. For the spectrograph, an all-reflecting, Thevenin-type
  concentric spectrograph has been designed. This design offers excellent
  image quality both spectrally and spatially along a long slit and it
  is compact and easily accommodated.

---------------------------------------------------------
Title: A coronal optical imager for a solar probe
Authors: Lamy, P.; Koutchmy, S.
1996AdSpR..17c..95L    Altcode: 1996AdSpR..17...95L
  A Coronal Optical Imager (COI) can make a significant contribution
  to a solar probe, for instance, by detecting the faintest plasma and
  magnetic structures, by analyzing the He/H ratio and the cool plasma
  component and by observing possible sources of dust near the Sun. We
  describe an instrument which combines the capability of EUV, UV and
  visible imaging as well as visible polarimetry, and propose two versions
  respectively adapted to a spinning and a 3-axis stabilized probes.

---------------------------------------------------------
Title: Observations of Comet P/Faye 1991 XXI with the Planetary
    Camera of the Hubble Space Telescope
Authors: Lamy, P. L.; Toth, I.; Grün, E.; Keller, H. U.; Sekanina,
   Z.; West, R. M.
1996Icar..119..370L    Altcode:
  Comet P/Faye 1991 XXI (1991 n) was observed with the planetary
  camera (PC) of the Hubble Space Telescope (HST) between October
  29 and November 21, 1991, when its geocentric distance was in the
  range 0.62-0.67 AU. The resulting high resolution-a single PC pixel
  projected to a distance of ∼20 km at the comet-made it possible to
  clearly discriminate the nucleus and to study the dust coma within
  ∼100 km from the nucleus. The spherical aberration which affected
  the early operation of the HST has severely complicated the analysis
  and image restoration using the Richardson-Lucy method has failed to
  give satisfactory results. The coma is dominated by the point spread
  function (PSF) of the nucleus up to a radial distance of ∼100 km
  and cannot be recovered. Beyond, it is affected by the spherical
  aberration up to approximately 750 km and was analyzed by comparison
  with a grid of models convolved with appropriate PSFs. Beyond 750 km,
  it remains unaffected and can be studied directly. From the outer to
  the innermost regions, the coma presents an elongated shape which may
  be explained either by an active source on the nucleus or, more likely,
  by a projection effect of the dust tail. If this second interpretation
  is correct, then the temporal evolution of the comet is very slow
  and smooth, suggesting an extended source of dust on the nucleus. The
  dust production rate, corrected for the projection effect of the tail,
  amounts to 125 kg sec<SUP>-1</SUP>.

---------------------------------------------------------
Title: Summary Remarks
Authors: Lamy, Ph. L.
1996ASPC..104..527L    Altcode: 1996IAUCo.150..527L; 1996pcdi.conf..527L
  No abstract at ADS

---------------------------------------------------------
Title: An Optical Instrument to Characterize Individual Dust Particles
Authors: Giovane, F.; Gustafson, B. A. S.; Lamy, Ph. L.
1996ASPC..104..247G    Altcode: 1996pcdi.conf..247G; 1996IAUCo.150..247G
  No abstract at ADS

---------------------------------------------------------
Title: Laboratory Measurements of Light Scattering by Dust Particles
Authors: Combet, Pp.; Lamy, Ph. L.
1996ASPC..104..409C    Altcode: 1996pcdi.conf..409C; 1996IAUCo.150..409C
  No abstract at ADS

---------------------------------------------------------
Title: Observations of the comet Hyakutake by the LASCO coronagraph
    on the SOHO satellite.
Authors: Andrews, M. D.; Paswaters, S. E.; Brueckner, G. E.; Korendyke,
   C. M.; Dere, K. P.; Howard, R. A.; Michels, D. J.; Moses, J. D.;
   Morril, J. S.; Moulton, N. E.; Socker, D. G.; St. Cyr, O. C.; Wang,
   D.; Lamy, P. L.; Llebaria, A.; Bout, M. V.; Schwenn, R.; Podlipnik,
   B.; Bedford, D. K.; Biesecker, D. A.; Eyles, C. J.; Plunket, S.;
   Simnet, G. M.
1996BAAS...28.1195A    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Dust Flux Analyser experiment for the Rosetta mission
Authors: Leese, M. R.; McDonnell, J. A. M.; Green, S. F.; Busoletti,
   E.; Clark, B. C.; Colangeli, L.; Crifo, J. F.; Eberhardt, P.; Giovane,
   F.; Grün, E.; Gustafson, B.; Hughes, D. W.; Jackson, D.; Lamy, P.;
   Langevin, Y.; Mann, I.; McKenna-Lawlor, S.; Tanner, W. G.; Weissman,
   P. R.; Zarnecki, J. C.
1996AdSpR..17l.137L    Altcode: 1996AdSpR..17..137L
  We present the description of a design for a proposed Dust Flux Analyser
  for the Rosetta cometary mission. A concept first developed for the
  NASA/ESA Tempel II Rendezvous and Halley Intercept Mission /1/, the
  instrument is able to measure dust particle parameters and fluxes over
  a velocity range typical of emission from cometary surfaces. It would
  be mounted on the Rosetta Orbiter and would measure the variation in
  flux rate throughout all mission phases at the comet. The instrument
  would measure particle flux, velocity, momentum and density, shape
  and scattering properties.

---------------------------------------------------------
Title: Concepts for Dust Velocity Measurements on a Cometary Orbiter
Authors: Perruchot, S.; Lamy, Ph. L.; Giovane, F.; Gustafson, B. A. S.
1996ASPC..104..255P    Altcode: 1996IAUCo.150..255P; 1996pcdi.conf..255P
  No abstract at ADS

---------------------------------------------------------
Title: The Large Angle Spectroscopic Coronagraph (LASCO)
Authors: Brueckner, G. E.; Howard, R. A.; Koomen, M. J.; Korendyke,
   C. M.; Michels, D. J.; Moses, J. D.; Socker, D. G.; Dere, K. P.;
   Lamy, P. L.; Llebaria, A.; Bout, M. V.; Schwenn, R.; Simnett, G. M.;
   Bedford, D. K.; Eyles, C. J.
1995SoPh..162..357B    Altcode:
  The Large Angle Spectroscopic Coronagraph (LASCO) is a three
  coronagraph package which has been jointly developed for the Solar
  and Heliospheric Observatory (SOHO) mission by the Naval Research
  Laboratory (USA), the Laboratoire d'Astronomie Spatiale (France),
  the Max-Planck-Institut für Aeronomie (Germany), and the University
  of Birmingham (UK). LASCO comprises three coronagraphs, C1, C2, and C3,
  that together image the solar corona from 1.1 to 30 R<SUB>⊙</SUB> (C1:
  1.1 - 3 R<SUB>⊙</SUB>, C2: 1.5 - 6 R<SUB>⊙</SUB>, and C3: 3.7 - 30
  R<SUB>⊙</SUB>). The C1 coronagraph is a newly developed mirror version
  of the classic internally-occulted Lyot coronagraph, while the C2 and
  C3 coronagraphs are externally occulted instruments. High-resolution
  imaging spectroscopy of the corona from 1.1 to 3 R<SUB>⊙</SUB> can
  be performed with the Fabry-Perot interferometer in C1. High-volume
  memories and a high-speed microprocessor enable extensive on-board image
  processing. Image compression by a factor of about 10 will result in
  the transmission of 10 full images per hour.

---------------------------------------------------------
Title: Comet 19P/Borrelly
Authors: Lamy, P.
1995IAUC.6204....2L    Altcode:
  P. Lamy, Laboratoire d'Astronomie Spatiale, Marseille, and his team
  report: "Using the Wide Field Planetary Camera 2 of the Hubble Space
  Telescope, we have detected a highly elongated nucleus rotat- ing
  with a synodic period of 24.7 hr. The prolate spheroid that gives
  the best fit to the nuclear-magnitude light curve has major and minor
  axes dimensions of 8.3 and 3.3 km, respectively, assuming a geometric
  albedo of 4 percent. We estimate that about 10 percent of the surface
  area is active."

---------------------------------------------------------
Title: Visible and Radio Observations of Comet 19P/Borrelly
Authors: Bockelée-Morvan, D.; Biver, N.; Colom, P.; Crovisier, J.;
   Gérard, E.; Jorda, L.; Davies, J. K.; Dent, B.; Colas, F.; Despois,
   D.; Paubert, G.; Lamy, P.
1995DPS....27.3308B    Altcode: 1995BAAS...27.1144B
  No abstract at ADS

---------------------------------------------------------
Title: HST Observations of the Nucleus of Comet 19P/Borrelly 1994 I
Authors: Lamy, P. L.; Toth, I.; Weaver, H. A.
1995DPS....27.3315L    Altcode: 1995BAAS...27.1145L
  No abstract at ADS

---------------------------------------------------------
Title: Temporal and Spatial Variations among the SL9 Fragments
Authors: Weaver, H. A.; A'Hearn, M. F.; Arpigny, C.; Feldman, P. D.;
   Lamy, Ph.; Meech, K. J.; Noll, K. S.; Smith, T. E.
1995DPS....27.2016W    Altcode: 1995BAAS...27Q1115W
  No abstract at ADS

---------------------------------------------------------
Title: The Hubble Space Telescope (HST) Observing Campaign on Comet
    Shoemaker- Levy 9
Authors: Weaver, H. A.; A'Hearn, M. F.; Arpigny, C.; Boice, D. C.;
   Feldman, P. D.; Larson, S. M.; Lamy, P.; Levy, D. H.; Marsden, B. G.;
   Meech, K. J.; Noll, K. S.; Scotti, J. V.; Sekanina, Z.; Shoemaker,
   C. S.; Shoemaker, E. M.; Smith, T. E.; Stern, S. A.; Storrs, A. D.;
   Trauger, J. T.; Yeomans, D. K.; Zellner, B.
1995Sci...267.1282W    Altcode:
  The Hubble Space Telescope made systematic observations of the
  split comet P/Shoemaker-Levy 9 (SL9) (P designates a periodic comet)
  starting in July 1993 and continuing through mid-July 1994 when the
  fragments plunged into Jupiter's atmosphere. Deconvolutions of Wide
  Field Planetary Camera images indicate that the diameters of some
  fragments may have been as large as ~2 to 4 kilometers, assuming
  a geometric albedo of 4 percent, but significantly smaller values
  (that is, &lt;1 kilometer) cannot be ruled out. Most of the fragments
  (or nuclei) were embedded in circularly symmetric inner comae from July
  1993 until late June 1994, implying that there was continuous, but weak,
  cometary activity. At least a few nuclei fragmented into separate,
  condensed objects well after the breakup of the SL9 parent body, which
  argues against the hypothesis that the SL9 fragments were swarms of
  debris with no dominant, central bodies. Spectroscopic observations
  taken on 14 July 1994 showed an outburst in magnesium ion emission that
  was followed closely by a threefold increase in continuum emission,
  which may have been caused by the electrostatic charging and subsequent
  explosion of dust as the comet passed from interplanetary space into
  the jovian magnetosphere. No OH emission was detected, but the derived
  upper limit on the H_2O production rate of ~10<SUP>27</SUP> molecules
  per second does not necessarily imply that the object was water-poor.

---------------------------------------------------------
Title: Direct detection of a cometary nucleus with the Hubble Space
    Telescope.
Authors: Lamy, P. L.; Toth, I.
1995A&A...293L..43L    Altcode:
  We report the unambiguous detection with the Planetary Camera of the
  Hubble Space Telescope of the nucleus of comet P/Faye 1991XXI during
  its last perihelion passage when it was at 0.6AU from the Earth. The
  high resolution of the HST allowed to discriminate the nucleus against
  the bright coma. The reduced V magnitude of the nucleus ranges between
  15.5 and 15.9. Assuming a geometric albedo of 0.04, we found a rather
  spherical body with a mean radius of 2.68km.

---------------------------------------------------------
Title: Discrimination of Point-like Objects in Astronomical Images
    using Surface Curvature
Authors: Llebaria, A.; Lamy, P.; Malburet, P.
1995ASPC...77..484L    Altcode: 1995adass...4..484L
  A new method for the discrimination of point-like objects in
  astronomical images is presented. The method makes use of the surface
  curvature of the image, without any a priori knowledge of the shape
  of the point-like objects.

---------------------------------------------------------
Title: The LASCO database at LAS
Authors: Mathieu, C.; Llebaria, A.; Lamy, P.
1995VA.....39..109M    Altcode:
  In the framework of the SOHO (Solar Heliospheric Observatory) space
  mission of observation of the sun, conducted jointly by ESA and NASA,
  the Marseilles Laboratoire d'Astronomie Spatiale (LAS) contributes
  to the LASCO experiment — a study of the Solar corona — within
  an international consortium. Our laboratory participates in LASCO
  data reduction and is responsible for setting up a national database
  for French investigators. This database shall provide access to a
  huge amount of data, resulting from the collection and archiving of
  about 180 images per day (each image having a size between 2 and 4
  Mo), during the whole mission duration (2 years; launch scheduled in
  September 1995). Of a relational structure (Sybase), the database is
  designed to store calibration images, from before and after launch,
  as well as mission images. It is intended to build interfaces to
  automatically load the new images into the database and into the
  IDL image processing software. Data will be made available to French
  astronomers through a WWW server which will provide compressed images,
  transferable via networks. The server will also offer interactive
  access to the data and will deliver the necessary information on how
  to retrieve the images and on the status of the ongoing mission. Tools
  developed at ESO, such as WDB or STARCAT, will be used appropriately.

---------------------------------------------------------
Title: The coronal aureole.
Authors: Fang, Y.; Lamy, P. L.; Llebaria, A.
1995A&A...293..208F    Altcode:
  We calculate the coronal aureole using the Fourier transform and we
  show that the outer corona significantly contributed to its value. We
  further propose a new, simple mathematical method which allows to derive
  the scattering function directly from two observational images taken
  successively during an eclipse. This method is successfully tested
  using different models of the scattering function.

---------------------------------------------------------
Title: Pulsars at 1 MeV: the Crab and PSR 1509-58.
Authors: Combet, P.; Lamy, P. L.
1995AdSpR..15j..65C    Altcode: 1995AdSpR..15R..65C
  The Compton Imaging Telescope COMPTEL observed at an early stage of the
  CGRO sky survey pulsed emission from the two classical γ-ray pulsars,
  Crab and Vela. Further efforts were necessary to detect one of the
  four new pulsars detected by the other CGRO instruments, namely PSR
  1509-58. These are the only three pulsars detected so far at an energy
  of 1 MeV. In spite of the similarity of their timing parameters, the
  Crab pulsar and PSR 1509-58 display very different characteristics in
  their MeV emissions, observed by COMPTEL.

---------------------------------------------------------
Title: HST Observations of Comet P/Faye 1991 XXI
Authors: Lamy, P. L.; Toth, I.; Grün, E.; Keller, H. U.; Sekanina,
   Z.; West, R. M.
1994BAAS...26.1552L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Capabilities of the Cosmic Dust Analyser (CDA) for the
    Mission CASSINI
Authors: Srama, R.; Grün, E.; Fechtig, H.; Jeßberger, E. K.;
   Pernicka, E.; Lura, F.; Möhlmann, D.; Wäsch, R.; Ahrens, J.; Auer,
   S.; Cruise, A. M.; Havnes, O.; Igenbergs, E.; Johnson, T. V.; Lamy,
   P.; Morfill, G. E.; Schwehm, G. H.; Svestka, J.; Tuzzolino, A. J.;
   Zook, H. A.; Cassini-Cda-Team
1994DPS....26.2109S    Altcode: 1994BAAS...26.1142S
  No abstract at ADS

---------------------------------------------------------
Title: HST Monitoring of Comet P/Shoemaker-Levy 9
Authors: Weaver, H. A.; Noll, K. S.; Storrs, A. D.; Smith, T. E.;
   A'Hearn, M. F.; Arpigny, C.; Feldman, P. D.; Boice, D. C.; Stern,
   S. A.; Lamy, P. L.; Larson, S. M.; Levy, D. H.; Scotti, J. V.; Marsden,
   B. G.; Meech, K. J.; Shoemaker, C. S.; Shoemaker, E. M.; Sekanina,
   Z.; Trauger, J. T.; Yeomans, D. K.; Zellner, B.
1994DPS....26.0101W    Altcode: 1994BAAS...26.1564W
  No abstract at ADS

---------------------------------------------------------
Title: IR Observations of the K and F Corona During the 1991 Eclipse
Authors: Kuhn, J. R.; Lin, H.; Lamy, P.; Koutchmy, S.; Smartt, R. N.
1994IAUS..154..185K    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The potential of the dust grains of comet halley
Authors: Lamy, P.; Lafon, J. -P. J.; Dumas, C.
1993AdSpR..13j.259L    Altcode: 1993AdSpR..13..259L
  We calculate the electrostatic potential of silicate, graphite and
  carbon submicronic grains in the coma of comet P/Halley located at
  1 AU from the Sun using the “orbit-limited” solution. The physical
  properties of the materials as well as the plasma parameters of the
  subsolar cometosheath are taken into account. We find that the potential
  lies between -3 and +4 volts in all cases, under likely conditions. It
  could be negative, between 0 and -10 volts, if the plasma would be
  a little more dense than usually admitted, as suggested by recent
  measures.

---------------------------------------------------------
Title: Status of the LASCO Instrument Development Program
Authors: Moses, D.; Brueckner, G. E.; Howard, R. A.; Koomen, M. J.;
   Korendyke, C. M.; Michels, D. J.; Socker, D. G.; Lamy, P.; Schwenn,
   R.; Simnett, G. M.
1993BAAS...25.1192M    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Absolute Photometry of the Dust Tail of Comet P/Halley
Authors: Lamy, P.; Malburet, P.
1993LPICo.810..178L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Observation of Comet Faye (1991n) with the Hubble Space
    Telescope
Authors: Lamy, P.; Toth, I.
1993LPICo.810..179L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Changing Properties of the Dust Coma of P/Halley: Implications
    for an Inhomogeneous Nucleus
Authors: Lamy, P.; Cosmovici, C.; Schwarz, G.
1993LPICo.810..180L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Large Angle Spectroscopic Coronagraph (LASCO): visible
    light coronal imaging and spectroscopy.
Authors: Brueckner, G. E.; Howard, R. A.; Koomen, M. J.; Korendyke,
   C.; Michels, D. J.; Socker, D. G.; Lamy, P.; Llebaria, A.; Maucherat,
   J.; Schwenn, R.; Simnett, G. M.; Bedford, D. K.; Eyles, C. J.
1992ESASP.348...27B    Altcode: 1992cscl.work...27B
  The Large Angle Spectroscopic Coronagraph (LASCO) is a triple
  coronagraph being jointly developed for the SOlar and Heliospheric
  Observatory (SOHO) mission by the Naval Research Laboratory (USA),
  the Laboratoire d'Astronomie Spatiale (France), the Max Planck
  Institut für Aeronomie (Germany), and the University of Birmingham
  (UK). LASCO comprises three nested coronagraphs (C1, C2, and C3)
  that image the solar corona from 1.1 R<SUB><SUB>sun</SUB></SUB> to
  30 R<SUB><SUB>sun</SUB></SUB>.

---------------------------------------------------------
Title: No Evidence of a Circumsolar Dust Ring from Infrared
    Observations of the 1991 Solar Eclipse
Authors: Lamy, P.; Kuhn, J. R.; Lin, H.; Koutchmy, S.; Smartt, R. N.
1992Sci...257.1377L    Altcode:
  During the past 25 years there have been many attempts to detect a
  possible dust ring around the sun, with contradictory results. Before
  the 1991 eclipse, infrared eclipse experiments used single-element
  detectors to scan the corona along the ecliptic for excess surface
  brightness peaks. The availability of relatively large-format infrared
  array detectors now provides a considerable observational advantage:
  two-dimensional mapping of the brightness and polarization of the corona
  with high photometric precision. The 1991 eclipse path included the
  high-altitude Mauna Kea Observatory, a further advantage to measure the
  corona out to large angular distances from the sun. Results are reported
  from an experiment conducted on Mauna Kea with a HgCdTe-array detector
  sensitive to wavelengths between 1 and 2.5 micrometers, using broad-band
  J, H, and K filters. Although the sky conditions were not ideal, the H-
  and K-band surface brightnesses clearly show the inhomogeneous structure
  in the K-corona and the elliptical flattening of the F-corona, but no
  evidence of a circumsolar, local dust component out to 15 solar radii.

---------------------------------------------------------
Title: LASCO - Large Angle Spectrometric Coronagraph for SOHO
Authors: Howard, R. A.; Brueckner, G. E.; Dere, K. P.; Korendyke,
   C. M.; Koomen, M. J.; Michels, D. J.; Moses, D.; Socker, D. G.;
   Schwenn, R.; Inhester, B.; Lamy, P.; Maucherat, A.; Simnett, G. M.;
   Eyles, C.
1992AAS...180.3307H    Altcode: 1992BAAS...24..781H
  No abstract at ADS

---------------------------------------------------------
Title: The Physics and Dynamics of Charged Dust Grains
Authors: Lamy, P.
1992ibpd.conf..369L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Zodiacal Light
Authors: Lamy, P.
1992iawi.conf..251L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Laboratory Spectroscopy for ISO Report of the ISO Working-Group
Authors: Encrenaz, T.; Crovisier, J.; D'Hendecourt, L.; Lamy, P.;
   Tully, J. A.
1992iawi.conf..141E    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Data Analysis of the HST Observations of Comet P/Faye
Authors: Lamy, Ph.; Llebaria, A.; Adorf, H. -M.
1992ESOC...44..481L    Altcode: 1992swhs.conf..481L
  No abstract at ADS

---------------------------------------------------------
Title: Photomultiplier for optically probing Comet Halley
Authors: Giovane, Frank; Eichhorn, G.; McKisson, J.; Weinberg,
   J. L.; Weisenberger, Andrew; Lamy, P.; Llebaria, A.; Detaille, M;
   Levasseur-Regourd, A. C.; Le Blanc, J. M.
1991ApOpt..30.2579G    Altcode:
  A low mass eight-color channel photopolarimeter was developed
  for the Giotto spacecraft. Utilizing the spin of the spacecraft,
  a multichannel plate photomultiplier, and a unique optical design,
  the instrument required no moving parts to measure color and linear
  polarization. The photopolarimeter collected data as the spacecraft
  passed through the coma of Comet Halley on March 13 and 14, 1986. This
  instrument's design, calibration, and reduction are discussed and some
  final results are presented.

---------------------------------------------------------
Title: Changing Properties of the Dust Coma of P/Halley: Implications
    for an Inhomogeneous Nucleus
Authors: Lamy, P.; Cosmovici, C.; Schwarz, G.
1991LPICo.765..130L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Electric Effects on Cometary Grains
Authors: Lafon, J. P. J.; Lamy, Ph.; Bouzinac, C.
1991isrs.conf..213L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Physical Properties of Cometary Dust
Authors: McDonnell, J. A. M.; Lamy, P. L.; Pankiewicz, G. S.
1991ASSL..167.1043M    Altcode: 1991cphe.conf.1043M; 1991IAUCo.116.1043M
  Prior to the 1986 apparition of Comet Halley, all attempts to
  determine the physical properties of cometary dust were limited to
  remote observations and the analysis of various particles captured by
  the earth's atmosphere. The in situ measurements made by the three
  spacecraft that passed within 10,000 km of the nucleus provided the
  first opportunity to investigate both the full size-range of particles
  and the complete process of dust production. Information on composition
  is derived through mass spectra and the scattering and emission of light
  from the grains, while the dynamics of the dust coma can be modeled
  from the three separate sets of measurements made over a period of
  eight days.

---------------------------------------------------------
Title: Future Observations of the F-Corona with the LASCO Coronagraph
    Space Experiment
Authors: Lamy, P. L.; Llebaria, A.; Maucherat, A.; Koutchmy, S.;
   Giovane, F.
1991ASSL..173..191L    Altcode: 1991IAUCo.126..191L; 1991oeid.conf..191L
  No abstract at ADS

---------------------------------------------------------
Title: Synthetic Maps of the Brightness and Polarization of the
    F-Corona
Authors: Fang, Y.; Lamy, P. L.; Llebaria, A.
1991ASSL..173..195F    Altcode: 1991oeid.conf..195F; 1991IAUCo.126..195F
  No abstract at ADS

---------------------------------------------------------
Title: The Optical Properties of Interplanetary Dust (invited Review)
Authors: Lamy, P. L.; Perrin, J. M.
1991ASSL..173..163L    Altcode: 1991oeid.conf..163L; 1991IAUCo.126..163L
  No abstract at ADS

---------------------------------------------------------
Title: On the Validity of Effective-Medium Theories in the Case of
    Light Extinction by Inhomogeneous Dust Particles
Authors: Perrin, J. -M.; Lamy, P. L.
1990ApJ...364..146P    Altcode:
  The application of Maxwell-Garnett and Bruggeman effective-medium
  theories to the problem of light scattering by inhomogeneous dust
  particles is investigated. It is shown that in the framework of
  classical electrodynamics these theories are not rigorously valid when
  applied to particles. Numerical computations of scattering using a
  discrete dipole approximation for very small grains composed of a matrix
  material with embedded inclusions are carried out, and the results are
  compared with results obtained using these effective-medium theories. It
  is shown that the application of these theories to the studies of the
  interactions of light with inhomogeneous dust particles is limited.

---------------------------------------------------------
Title: Optical linear polarization measurements of Comet Halley from
    the Giotto Halley Optical Probe Experiment.
Authors: Weisenberger, A. G.; Giovane, F.; Eichhorn, G.; Lamy, P.;
   Llebaria, A.
1990BAAS...22..744W    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The dust tail of comet Halley.
Authors: Lamy, P. L.
1990ch2..book....1L    Altcode: 1990ch......2....1L
  Contents: 1. From early ages to the present day: an historical
  perspective of cometary dust tails. 2. From streamers to striae:
  a perspective on structures in cometary tails. 3. A good perspective
  on the dust tail of comet Halley. 4. The dust tail of comet Halley in
  1986. 5. Photopolarimetric properties of the tail and its modelling.

---------------------------------------------------------
Title: The color of the zodiacal light and the size distribution
    and composition of interplanetary dust
Authors: Perrin, J. -M.; Lamy, P. L.
1989A&A...226..288P    Altcode:
  The color of the zodiacal light is studied in the general context
  of light scattered by dust particles. It is shown that the color
  is controlled by various mechanisms in a complex way. The spectral
  variation of the complex index of refraction, the size distribution
  function and the roughness of the dust grains all play a significant
  role in the color of the scattered light. It is also shown that the
  very geometrical conditions of observation of the zodiacal light result
  in a color effect which depends upon the elongation.

---------------------------------------------------------
Title: Optical properties of irregular interstellar grains.
Authors: Perrin, J. M.; Lamy, P. L.
1989IAUS..135P.381P    Altcode:
  In order to study the interaction of light with interstellar grains,
  the authors represent an irregular particle by a network of interacting
  dipoles whose polarizability is determined in a first approach by
  the Clausius-Mossoti relationship. Typically, 10000 dipoles are
  considered. In the case of spherical particles, the results from Mie
  theory are fully recovered.

---------------------------------------------------------
Title: Comet P/Halley at a heliocentric preperihelion distance of
    2.6 AU - Jet activity and properties of the dust coma
Authors: Lamy, P. L.; Malburet, P.; Llebaria, A.; Koutchmy, S.
1989A&A...222..316L    Altcode:
  This paper presents an in-depth analysis of a high-resolution
  photograph of comet P/Halley obtained on September 12, 1985 when it
  was a heliocentric distance of 2.6 AU preperihelion. The coma has a
  diameter of 138,000 km and exhibits structures which are interpreted
  as three jets, one best seen in the outer part of the coma extending
  to 29000 km and the two others, in the inner part extending to about
  7000 km. The integrated magnitude and radial profiles of the coma are
  given showing that the comet does not follow the simple steady-state,
  radial outflow model. By combining the photometric result with nearly
  simultaneous ultraviolet and infrared observations, it is found that
  the strong reddening in the ultraviolet gradually levels off in the
  visible as the color becomes neutral at 2 microns and blue beyond 3
  microns. A geometric albedo at zero phase angle of 0.04 is obtained,
  as well as a dust production rate of 30 to 120 kgs.

---------------------------------------------------------
Title: Infrared properties of rough cometary grains
Authors: Perrin, J. M.; Lamy, P. L.
1989AdSpR...9c.241P    Altcode: 1989AdSpR...9..241P
  In order to study the interaction of light with cometary grains,
  we represent an irregular particle by a network of interacting
  dipoles whose polarizability is determined in a first approach by
  the Clausius-Mossiti relationship. Typically, 10000 dipoles are
  considered. In the case of spherical particles, the results from Mie
  theory are fully recovered. The main interest of this method is to
  study with a good accuracy the implications of surface roughness and/or
  inhomogeneities on optical properties in the infrared spectral range,
  particularly of the silicate emission features.

---------------------------------------------------------
Title: Optical properties of organic grains: Implications for
    interplanetary and cometary dust
Authors: Lamy, Philippe L.; Perrin, Jean-Marie
1988Icar...76..100L    Altcode:
  On the basis of the organic material "tholin" whose optical constants
  have been measured by B. N. Khare et al. (1984, Icarus 60, 127-137),
  we investigate the optical properties of tholin grains and find an
  original behavior, intermediate between dielectric and absorbing
  material. Solving for the interaction with the solar radiation field,
  we obtain the ratio β of the radiation pressure and gravitational
  forces and the temperature distribution. The temperature is a strong
  function of the size of the grains with the submicron grains much
  hotter than the blackbody. The presence of such an organic material in
  cometary dust looks very promising for explaining several "puzzling"
  observations such as the CN jets and the absence of the silicate
  emission feature at heliocentric distances beyond ⋍1.5 AU.

---------------------------------------------------------
Title: Light scattering of large rough particles application to
    cometary grains.
Authors: Lamy, Philippe L.; Perrin, J. M.
1988ioch.rept..156L    Altcode:
  While the electromagnetic field scattered by a spherical particle is
  classically obtained by the Helmholtz equation, the general case of
  an arbitrary particle may be investigated in the general framework of
  the interaction of a wave with a scattering potential. A wave function
  then satisfies the Schroedinger equation. The general solution of the
  Schroedinger equation is given. The main disadvantage of this approach
  are its restriction to large particles and its scalar nature preventing
  the calculation of the polarization. However, Perrin and Lamy have
  shown how to avoid the second limitation and retrieve a vectorial
  description. They proved that in the case of large spheres when the
  ad hoc assumptions are satisfied, the expression of the scattering
  amplitude may be approximated by an expansion series in partial waves,
  i.e., on a discrete basis. The analogy may be generalized, and the ratio
  of the two components for a rough particle obtained by taking the ratio
  of the reflectivities for the two directions of polarization. These
  reflectivities involve the simple and double reflections calculated
  following the method developed by Wolff for rough surfaces. The theory
  is further detailed.

---------------------------------------------------------
Title: Laboratory Measurements of Light Scattering by Dust Particles
Authors: Bliek, P.; Lamy, P.
1988ASSL..149..253B    Altcode: 1988ecda.book..253B
  No abstract at ADS

---------------------------------------------------------
Title: Etude de la dynamique du nuage zodiacal par la mesure du
    décalage Doppler.
Authors: Lamy, P.; Koutchmy, S.; Bücher, A.; Robley, R.
1988jopl.conf..227L    Altcode:
  At the Pic-du-Midi Observatory, the authors have started a program
  to observe the spectrum of the zodiacal light in the region of
  the b absorption lines of Mg I. They use a 1 m spectrograph with a
  holographic grating followed by a focal reducer to obtain a 19 Å/mm
  dispersion over the micro-channel plate camera. Calibrated spectra
  obtained with an exposure time of 10 minutes systematically show earth
  atmospheric emission lines attributed to both N I and OH. The temporal
  variability of these emissions prevents an accurate determination of
  the line profiles.

---------------------------------------------------------
Title: Observations et propriétés des poussières de la comète
    de Halley.
Authors: Lamy, P.; Perrin, J. M.; Koutchmy, S.; Grün, E.; Llebaria,
   A.; Malburet, P.
1988jopl.conf..211L    Altcode:
  The authors present the results of various observations and analysis
  of the dust grains of comet Halley.

---------------------------------------------------------
Title: Comet P/Halley - Implications of the mass distribution function
    for the photopolarimetric properties of the dust coma.
Authors: Lamy, P. L.; Gruen, E.; Perrin, J. M.
1987A&A...187..767L    Altcode:
  The dust particle fluences measured aboard the Vega (SP-1 and SP-2
  impact sensors) and Giotto probes (DIDSY impact sensors) are analyzed
  to obtain the differential size distribution function of the dust in
  the coma of comet Halley. The brightness integral is then calculated
  for perfectly spherical (Mie scattering) and rough grains of various
  compositions. It is shown that the photopolarimetric observations
  rule out the dominating presence of weakly obsorbing silicates such
  as olivine but are compatible with rough moderately absorbing silicate
  grains having a density decreasing with radius and with rough graphite
  grains. A mixture of the two types gives in fact the best agreement
  with the observations.

---------------------------------------------------------
Title: The Dust Tail of Comet p/ Halley in 1986APR
Authors: Lamy, P. L.; Pedersen, H.; Vio, R.
1987A&A...187..661L    Altcode:
  Images of the dust tail of comet Halley were obtained with the
  ESO wide-field CCD camera during April 1986 with the Johnson B,
  V and R filters in polarized light. An analysis of selected images
  taken on April 6 and 11, processed for photometric analysis, is
  presented. Results are given for the absolute brightness, the color,
  the polarization and its variation with wavelength.

---------------------------------------------------------
Title: Compatibility of the in-situ mass distribution with
    photopolarimetricobservations of comet Halley.
Authors: Lamy, P. L.; Grün, E.; Perrin, J. M.
1987ESASP.278..409L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Similarity and diversity of the polarization of comets.
Authors: Perrin, J. -M.; Lamy, P. L.
1987ESASP.278..411P    Altcode: 1987dsc..proc..411P
  The polarization measurements of the dust coma of 10 comets
  including P/Halley were analyzed. Separation of the dust from the gas,
  emphasizing the value of the narrow-band and spectropolarimetric data,
  is outlined. Polarization curves are deduced, implying unambiguous
  differences in the physical properties of the cometary dust. The
  negative branch of polarization is discussed and intepreted as
  suggesting a rough surface for the grains.

---------------------------------------------------------
Title: Book Review: Interrelationship among circumstellar,
    interstellar, and planetary dust. Edited by Joseph A. Nuth III and
    Robert E. Stencel. NASA Conference Publication 2403, Proceedings of
    a workshop held at the Aspen Institute's Wye Plantation Conference
    Center, Wye, MD, February 27 to March 1, 1985
Authors: Lamy, Philippe L.
1987Icar...71..198L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: B00K-REVIEW - Properties and Interactions of Interplanetary
    Dust
Authors: Giese, R. H.; Lamy, P.
1987Sci...236.1009G    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Night sky optical spectrum from a high altitude observatory.
Authors: Louistisserand, S.; Bucher, A.; Koutchmy, S.; Lamy, P.
1987A&AS...68..539L    Altcode:
  Night sky spectrum between 380 and 660 nm with effective spectral
  resolution of 0.2 nm is presented for evaluation of effects
  produced by the different sources of light including lights of urban
  origin. Numerous emission lines superposed on a continuum spectrum
  are identified.

---------------------------------------------------------
Title: Radiation pressure and temperature of Beta Pictoris
    circumstellar dust grains.
Authors: Lamy, P.
1987BAAS...19..633L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Book-Review - Properties and Interactions of Interplanetary
    Dust 85TH Colloquium I.A.U. / Marseille 1984
Authors: Giese, R. H.; Lamy, P.
1987ApL....25..270G    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Book-Review - Properties and Interactions of Interplanetary
    Dust - 85TH Colloquium of the I.A.U. Marseille - 1984
Authors: Giese, R. G.; Lamy, P.
1987ApL....25..265G    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Ground-Based Large-Scale Monochromatic Images of Comet Halley
    during the Giotto Flyby
Authors: Koutchmy, S.; Lamy, P.; Loucif, M.; Malburet, P.
1986ESASP.250c..79K    Altcode: 1986ehc3.conf...79K
  A wide-field camera (f = 135 mm) equipped with an image-tube was set up
  at the geophysical observatory of Tamanrasset during the first half of
  March. Monochromatic images were obtained in CN (390 nm), CO<SUP>+</SUP>
  (426.3 nm) and in the continuum (582 nm), in March 14.19, a few hours
  after the Giotto flyby.

---------------------------------------------------------
Title: The Dust Tail of Comet Halley: Brightness, Colour, Polarisation
Authors: Lamy, P.; Pedersen, H.; Vio, R.
1986ESASP.250b..69L    Altcode: 1986ehc2.conf...69L
  Images of the dust tail of comet Halley were obtained with the ESO
  wide-field CCD camera during April 1986 with the Johnson B, V and
  R filters in polarized light. A preliminary analysis of selected
  images taken on April 6 and 11, processed for photometric analysis,
  is presented. Results are given for the absolute brightness, the color,
  the polarization and its variation with wavelength.

---------------------------------------------------------
Title: Comet Halley: Implications of the Impact Measurements for
    the Optical Properties of the Dust
Authors: Lamy, P. L.; Perrin, J. -M.
1986ESASP.250b..65L    Altcode: 1986ehc2.conf...65L
  The cumulative mass flux function obtained by VEGA-2 SP-2 impact
  instrument is used to calculate the brightness integral, for grains
  of various compositions, in the framework of Mie theory and of the
  authors' model for light scattering by rough grains. Polarization
  for large scattering angles and color in the ultra violet and visible
  range are also obtained. The results are compared with the space and
  ground-based observations. General indications on the properties of
  cometary dust are outlined.

---------------------------------------------------------
Title: Inner Coma Dust and Gas as a Function of Distance to the
Nucleus: Measurements from Giotto
Authors: Levasseur-Regourd, A. C.; Bertaux, J. -L.; Dumont, R.;
   Eichhorn, G.; Festou, M.; Giese, R. H.; Giovane, F.; Lamy, P.; Leblanc,
   J. M.; Llebaria, A.; Weinberg, J. L.
1986ESASP.250c.232L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Early resolved structures in the coma of Comet Halley
Authors: Dossin, F.; Guerin, P.; Koutchmy, S.; Lamy, P.; Malburet, P.
1986ESASP.250b.173D    Altcode: 1986ehc2.conf..173D
  Three high-resolution photographs of comet Halley were obtained on
  September 12, 1985 with the Schmidt telescope operated by CNRS and
  Liège University at the Observatoire de Haute-Provence on hypered
  Kodak 2415 film and exposure times of 1 hour. The best image (FWHM
  of 2 arcsec) has been analyzed in order to deduce the 2-dimensional
  distribution of light presumably scattered by the dust. Two jet-like
  structures are present in the near nuclear region, one extending outward
  up to 15 arcsec. The total absolute magnitude has also been determined.

---------------------------------------------------------
Title: Book-Review - Properties and Interactions of Interplanetary
    Dust
Authors: Giese, R. H.; Lamy, P.; Ingham, M. F.
1986Obs...106..130G    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Book-Review - Properties and Interactions of Interplanetary
    Dust
Authors: Giese, R. H.; Lamy, P.
1986S&T....72Q..41G    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Volume scattering function and space distribution of the
    interplanetary dust cloud
Authors: Lamy, P. L.; Perrin, J. -M.
1986A&A...163..269L    Altcode:
  The Volume Scattering Function (VSF) and the spatial distribution of the
  interplanetary dust cloud are examined by inversion of the brightness
  integral of the F-corona and the zodiacal light. Intensity and
  polarization observations are used to produce functional representations
  in the plane of symmetry of the interplanetary cloud, in the meridian
  plane, and at selected ecliptic latitudes. A modified fan model is
  shown to be compatible with the brightness data at d = 1 and 0.3 AU,
  and indicates that the VSF and the local polarization depend upon
  the heliocentric distance of the observer, but are independent of the
  latitude. The variations of the VSF and the polarization with respect
  to the scattering angle may be explained by the preferential removal
  of absorbing grains as beta-meteoroids.

---------------------------------------------------------
Title: Inner Coma Dust and Gas in Comet Halley as a Function of
Distance to the Nucleus: Measurements from GIOTTO
Authors: Levasseur-Regourd, A. -C.; Bertaux, J. L.; Dumont, R.;
   Eichhorn, G.; Festou, M. C.; Giese, R. H.; Giovane, F.; Lamy, P.;
   Leblanc, J. M.; Llebaria, A.; Weinberg, J. L.
1986BAAS...18..790L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Properties of Organic Interplanetary Grains
Authors: Lamy, P. L.; Perrin, J. M.
1986BAAS...18..820L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Book-Review - Properties and Interactions of Interplanetary
    Dust
Authors: Giese, R. H.; Lamy, P.
1986Sci...232.1654G    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Optical probing of comet Halley from the Giotto spacecraft
Authors: Levasseur-Regourd, A. C.; Bertaux, J. L.; Dumont, R.; Festou,
   M.; Giese, R. H.; Giovane, F.; Lamy, P.; Le Blanc, J. M.; Llebaria,
   A.; Weinberg, J. L.
1986Natur.321..341L    Altcode:
  The Halley optical probe experiment (HOPE) aboard the Giotto spacecraft
  has provided the first measurements of the optical properties of the
  dust and of some gaseous species (CN, C<SUB>2</SUB>, CO<SUP>+</SUP> and
  OH) from inside the coma of comet Halley. The dust spatial distribution,
  inferred from sunlight scattering, obeys an r<SUP>-2</SUP> law for
  distances from the nucleus r&gt;=2,000 km. The more rapid increase of
  dust density with distance observed in the innermost coma probably
  reflects the presence of a jet, or a surge of activity within a few
  hours before closest approach. The CN and OH signals increase more
  slowly than the dust signals, but faster than predicted by a simple
  model (of solar-excited resonance fluorescence) for the distribution
  of these species<SUP>1</SUP>. This effect is probably caused in part
  by the dust contribution, as well as by the production from parent
  molecules of OH and CN in an excited state.

---------------------------------------------------------
Title: The Giotto optical probe experiment
Authors: Levasseur-Regourd, A. C.; Bertaux, J. L.; Dumont, R.; Festou,
   M.; Giese, R. H.; Giovane, F.; Lamy, P.; Llebaria, A.; Weinberg, J. L.
1986gmis.rept..187L    Altcode:
  The Halley Optical Probe Experiment (HOPE) was designed to provide
  in-situ photopolarimetric data on the dust cloud and the gaseous
  atmosphere in Halley/s coma. The probe concept, instrumentation,
  and possibilities for cross-correlation between the HOPE results and
  those of other space and ground-based experiments are presented. The
  instrument was turned on successfully on 13 September 1985.

---------------------------------------------------------
Title: Periodic Comet Halley (1982i)
Authors: Ney, E. P.; Knutson, A. G.; Wootten, Alyn; Loren, R.;
   Koutchmy, S.; Lamy, P.
1986IAUC.4161....1N    Altcode:
  E. P. Ney and A. G. Knutson, University of Minnesota, report the
  following infrared magnitudes measured with a 26" diaphragm at the
  O'Brien Observatory: 1985 Dec. 12.08 UT, K = 6.8, L = 6.1, [8.6 micron]
  = -0.5, N = -1.8, [12.5 micron] = -1.9, [18 micron] = -3.3; Dec. 14.00,
  [8.6 micron] = 0.9, N = -0.8, [12.5 micron] = 0.0, [18 micron] = = -2.8;
  Dec. 25.05, J = 6.8, K = 7.1, L = 5.2, M = 3.1, [8.6 micron] = -0.5,
  N = -1.6, [12.5 micron] = -1.6, [18 micron] = -3.0; 1986 Jan. 1.0, N =
  -1.4, [12.5 micron] = -0.9; Jan. 7.9, H = 6.0, K = 6.1, L = 3.9, M =
  1.2, [8.6 micron] = -1.5, N = -2.8, [12.5 micron] = -2.6, [18 micron]
  = -4.0. The silicate feature at 10 micron is ~ 0.5 mag above the
  continuum. A. Wooten, National Radio Astronomy Observatory, reports:
  "R. Loren, University of Texas, obtained spectra of P/Halley in the
  region of the P(2,1) line of protonated water (H3O+) at 307.19241 GHz
  on Jan. 6 with the 4.9-m telescope of the Millimeter Wave Observatory
  at Fort Davis. No emission was detected, rms(TR*) = 0.85 placing a
  preliminary upper limit of 5 x 10**-27 s**-1 for the H3O+ production
  rate. Receiver tuning was verified through observation of CHEOH at
  307.16594 GHz in OMC-1." S. Koutchmy, Institut d'Astrophysique, Paris;
  and P. Lamy, Laboratoire d'Astronomie Spatiale, Marseilles, telex that
  100 image-tube spectra (180 A/mm resolution, range 350-700 nm) were
  obtained with the Haute Provence Observatory's 0.8-m telescope during
  1985 Dec. 10-15. CN emission was detected, extending up to 2 deg away
  from the sun, but no ions were noted until Dec. 12. From Dec. 13.8 UT
  onward the N2+ (0,0) line at 391.4 nm was seen in the vicinity of the
  coma and extending in the antisolar direction up to 2 deg. Observations
  with the Marly spectrograph (range 326-526 nm, dispersion 80 A/mm,
  slit width 50 micron, slit length projection 3'7, IIa-O hypered plates)
  on the 1.20-m f/6 telescope during 1985 Dec. 2.76-2.98 and 3.72-3.97
  UT revealed CN, C2 and C3 (all well observed); N2+ (0,0) extending
  over 16"; CO+ (3,0) lines at 400.18 and 402.4 nm extending over 37"
  and 14", respectively; CO2+ (0,1) at 367.4 nm was suspected; numerous
  Fraunhofer absorption lines (including H and K and several Fe lines)
  were also noted. Photographs (hypered IIIa-J and 2415 emulsions) of
  the plasma tail with the 0.62-m f/3.5 and 0.30-m f/2 Schmidt telescopes
  during Dec. 3- 15 revealed an inner part (extending &lt; 1 deg from the
  head) whose orientation oscillated about the antisolar direction with a
  maximum deviation of + 5P and a characteristic time of one to two days.

---------------------------------------------------------
Title: Cometary dust: observational evidences and properties.
Authors: Lamy, P. L.
1986acm..proc..373L    Altcode:
  Cometary dust in both the coma and the tail is observed by its
  scattered light and its thermal emission provided that they are
  carefully separated from the emission lines. Color, phase function,
  polarization and spectral signatures are the basic properties
  which help in characterizing the dust grains. There do not appear
  to be systematic differences among various comets as the reddening,
  the strong forward scattering and the polarization behavior appear
  to be wide-spread common features also shared by interplanetary dust
  grains. The interpretation of some of these features in terms of rough,
  slightly absorbing grains is discussed.

---------------------------------------------------------
Title: The Giotto Optical Probe Experiment.
Authors: Levasseur-Regourd, A. C.; Bertaux, J. L.; Dumont, R.; Festou,
   M.; Giese, R. H.; Giovane, F.; Lamy, P.; Llebaria, A.; Weinberg, J. L.
1986ESASP1070..187L    Altcode:
  The Halley Optical Probe Experiment (HOPE) has been designed to
  provide in-situ photopolarimetric data on both the dust cloud and the
  gaseous atmosphere in Halley's coma. The Optical Probe's concept is
  presented here, together with a description of the instrumentation
  and the possibilities for cross-correlation between the HOPE results
  and those of other space and ground-based-experiments. The instrument
  was turned on successfully on 13 September 1985.

---------------------------------------------------------
Title: Periodic Comet Halley (1982i)
Authors: Jewitt, D.; Meech, K.; Ricker, G.; Lamy, P.; Koutchmy, S.;
   Vial, J. C.
1985IAUC.4148....1J    Altcode:
  D. Jewitt, K. Meech, and G. Ricker, Massachusetts Institute of
  Technology, communicate: "Observations from McGraw-Hill Observatory
  on Kitt Peak over 4 nights show variable structures in the inner
  coma of P/Halley. Images were taken through broad and narrowband
  interference filters using the MIT 'MASCOT' CCD camera on the 1.3-m
  telescope. Jet-like structures were observed in position angles 358
  and 313 on Nov. 29 UT. The jets extended 10 000 km in the plane of
  the sky and had widths comparable to the atmospheric seeing. The
  jets were visible in both broad and narrowband continuum filters and
  are probably dust features. The jets showed no variation in position
  angle or brightness in an observing interval of &gt; 3 hr but were
  absent on the preceding and following nights." Meech and Jewitt also
  report: "Observations of P/Halley with the Kitt Peak 0.61-/0.91-m
  Schmidt telescope (with baked IIIa-J plates and exposure times
  30-60 min) show that extensive tail development has occurred within
  the past month. Observations on Nov. 6-9 showed only a transient,
  faint anti-solar tail (length 20' on Nov. 6.20) which faded in &lt;
  1 day. Observations on Dec. 4-8 show a persistent plasma tail (length
  &gt; 2.5 deg) displaying a classical streamer morphology. We are able
  to follow knots, kinks, and streamers in the tail for up to 6 hr. The
  measured speeds of 3 tail knots are 190, 216, and 240"/hr (39, 45, and
  50 +/- 5 km/s along the tail, km/s), considerably less than the solar
  wind speed but similar to the speeds measured in the tails of other
  comets. No evidence for acceleration of the features is seen. Two
  episodes of ray formation have been seen in 25 hr of observation;
  the rays form in ~ 1 hr and evolve over several hr, but fade in &lt;
  18 hr. The tail as a whole shows gross brightness changes from night
  to night. No dust tail is seen." P. Lamy, Laboratoire d'Astronomie
  Spatiale, Marseille, and S. Koutchmy, Institut d'Astrophysique, Paris,
  telex: "Four consecutive 1-hr-exposure IIIa-J hypered plates obtained
  between Dec. 6.79-6.96 UT by Koutchmy and J. C. Vial with the 0.62-m
  f/3 Schmidt telescope of Haute Provence Observatory show a disturbed,
  narrow, plasma tail of length &gt; 2 deg. The tail's inner part
  deviates southward from the anti-solar direction by 4.8 +/- 0.7 deg;
  the outer part widens and nears the anti-solar direction. The point
  of bifurcation seems to move radially outward with time."

---------------------------------------------------------
Title: Zodiacal Light and the Spatial Density of Interplanetary Grains
Authors: Lamy, P. L.; Perrin, J. M.
1985ASSL..119..239L    Altcode: 1985piid.proc..239L; 1985IAUCo..85..239L
  Using the Lamy and Perrin (1980) model of light scattering by large,
  rough grains, the compatibility of the observed properties of the
  zodiacal light with models of the spatial density of interplanetary
  grains is investigated. The agreement is not yet satisfactory and
  probably calls for further revision of the density distribution
  function. The previous conclusion that submicronic grains gives a
  nonnegligible contribution is confirmed.

---------------------------------------------------------
Title: Ground-based observations of the dust emission from comet
    Halley
Authors: Lamy, P.
1985AdSpR...5l.317L    Altcode: 1985AdSpR...5..317L
  A preliminary analysis of the dust emission from comet Halley is
  presented based on large scale observations of its dust tail. Selected
  images obtained between February 22 and May 10, 1986 are compared to
  synchrone-syndyne graphs to infer the history of the dust production
  and the properties of the dust, at least qualitatively. Quantitative
  modeling of the dust tall has also been initiated and preliminary
  results are shown for the cases of isotropic and anisotropic (jet)
  dust production.

---------------------------------------------------------
Title: The F-Corona and the Circum-Solar Dust Evidences and Properties
    (ir)
Authors: Koutchmy, S.; Lamy, P. L.
1985ASSL..119...63K    Altcode: 1985IAUCo..85...63K; 1985piid.proc...63K
  This review deals with the main properties of the F-corona. Analysis
  of its morphology and photometry allows to derive a new axisymmetric,
  non-spherical model. Polarization, color and infra-red properties are
  further considered. The authors suggest the existence of a variable
  "local" component superimposed on a quasi-stationary "far" component.

---------------------------------------------------------
Title: In-situ photopolarimetric measurements of dust and gas in
    the coma of Halley's comet
Authors: Levasseur-Regourd, A. -C.; Bertaux, J. -L.; Le Blanc, J. M.;
   Weinberg, J. L.; Giovane, F.; Dumont, R.; Festou, M.; Giese, R. H.;
   Lamy, P.; Llebaria, A.
1985AdSpR...5l.197L    Altcode: 1985AdSpR...5..197L
  The Halley Optical Probe Experiment (HOPE) on board the Giotto
  spacecraft has provided the first in-situ measurements, both of the
  dust and of some gaseous species, from inside the coma of the comet. The
  instrument has already been described /1/, together with first results
  /2/. The purpose of this note is to show how optical measurements can
  lead to in-situ information, how those were obtained during the 13-14
  march 1986 Halley fly-by, and what is the status of the data analysis.

---------------------------------------------------------
Title: Preliminary Results of a Dust Scattering Experiment
Authors: Bliek, P.; Lamy, P. L.; Courtes, G.
1985ASSL..119..231B    Altcode: 1985IAUCo..85..231B; 1985piid.proc..231B
  An experimental device of the nephelometer type for the study of the
  scattering properties of dust particles is presented. A fluidized bed
  generator produces a continuously flowing aerosol which is illuminated
  by either a He-Ne laser or a Xenon arc lamp with interference
  filters. The size of the dust particles ranges between 1 and 30
  microns. The scattering properties of dust particles are measured in
  the two directions of polarization. The first results are presented.

---------------------------------------------------------
Title: Properties and interactions of interplanetary dust
Authors: Giese, R. H.; Lamy, P.
1985ASSL..119.....G    Altcode: 1985piid.proc.....G; 1985IAUCo..85.....G
  The conference presents papers on zodiacal light and F-coronal
  observations as well as space, ground, laboratory and optical
  studies of interplanetary dust, the relationship between this dust
  and comets, its interactions with plasma, its dynamics and spatial
  distribution. Particular attention is given to ground-based observations
  of near ecliptic zodiacal light brightness, the change in near-ecliptic
  zodiacal light brightness with heliocentric distance, IRAS observations
  of interplanetary dust emission, and observation of the F-corona radial
  velocities field between 3 and 7 solar radii. Other topics include
  orbits of interplanetary dust particles inside 1 AU as observed by
  Helios, chemical and isotopic compositons of refractory elements in deep
  sea spherules, optical models of the three dimensional distribution
  of interplanetary dust, the particle-size-distribution function of
  cometary dust, laboratory simulation of chemical interactions of
  accelerated ions with dust and ice grains, and an analysis of IRAS'
  solar system dust bands.

---------------------------------------------------------
Title: Doppler Shifts Measurements of the Zodiacal Light at the PIC
    Midi Observatory
Authors: Robley, R.; Buecher, A.; Koutchmy, S.; Lamy, Ph.
1985ASSL..119...85R    Altcode: 1985IAUCo..85...85R; 1985piid.proc...85R
  The authors have started a program to observe the spectrum of the
  zodiacal light in the region of the b absorption lines of Mg I. They
  use a 1 meter spectrograph with a holographic grating followed by a
  focal reducer to obtain a 19 Å/mm dispersion over the micro-channel
  plate camera. Calibrated spectra obtained with an exposure time of 10
  minutes systematically show earth atmospheric emission lines attributed
  to both N I and OH. The temporal variability of these emissions
  prevents an accurate determination of the line profiles. The authors
  best processed measurements of Doppler shifts obtained during five
  nights do not allow to discriminate between circular and hyperbolic
  orbits of the interplanetary dust.

---------------------------------------------------------
Title: Optical Properties of Rough Grains: a Theoretical Study
Authors: Perrin, J. M.; Lamy, P. L.
1985ASSL..119..245P    Altcode: 1985IAUCo..85..245P; 1985piid.proc..245P
  Recent work on the light scattering by large rough particles has led
  the authors to propose a model based on the high-energy approximation,
  the laws of geometrical optics and a mathematical description of the
  properties of the particle roughness. The influence of the various
  parameters of the model including those characterizing the roughness
  on the total intensity and the polarization is presented.

---------------------------------------------------------
Title: Some Remarks on the Density of Interplanetary Dust Grains
Authors: Lamy, P. L.
1985ASSL..119..137L    Altcode: 1985piid.proc..137L; 1985IAUCo..85..137L
  The relevance of the bulk density as a physical parameter characterizing
  interplanetary dust grains is discussed. The various measurements which
  lead to a determination of this parameter are reviewed. The specific
  case of the collected interplanetary dust grains is considered.

---------------------------------------------------------
Title: A Coronascanner for a Sun Oriented Space Mission
Authors: Koutchmy, S.; Lamy, P. L.
1985ASSL..119..141K    Altcode: 1985IAUCo..85..141K; 1985piid.proc..141K
  No abstract at ADS

---------------------------------------------------------
Title: Photographic Observations of the Inner Zodiacal Light Aboard
    Saliout 7
Authors: Nikolskii, G.; Koutchmy, S.; Lamy, P. L.; Nesmianovich, I. A.
1985ASSL..119....7N    Altcode: 1985IAUCo..85....7N; 1985piid.proc....7N
  Color photographs of the inner zodiacal light were obtained aboard
  Salyut 7 with Kodak Ekta 400. Absolute calibrations were performed
  in-flight with attenuated sunlight. The photometric analysis was carried
  out in three colors and corrections were introduced for the O I emission
  of the F layers. The brightness of the zodiacal light along the ecliptic
  is found in good agreement with published data while its color is found
  slightly redder than the sun. Its out-of-ecliptic variation coincides
  neither with the fan nor the ellipsoidal model; the photometric axis
  is found near the projection of the orbital plane of Venus.

---------------------------------------------------------
Title: Astrophysical and geophysical observations with piramig/salyut
    7 experiment
Authors: Levasseur-Regourd, A. C.; Courtes, G.; Herse, M.; Koutchmy,
   S.; Lamy, P.; Muliarchik, T. M.; Rocca-Volmerange, B.; Savchenko,
   S. A.; Secher, B.; Tovmassian, H. M.; Beresovoy, A. N.; Chretien,
   J. L.; Ivanchenkov, A. S.; Djanibekov, V. A.; Lebedev, V. V.; Popov,
   L. I.; Savitskaya, S. E.; Serebrov, A. A.
1985AdSpR...5c..27L    Altcode: 1985AdSpR...5...27L
  The facility offered by the Salyut 7 vehicle has allowed
  teams of scientists of 3 CNRS french laboratories to develop
  an instrument optimized for several disciplines in astrophysics
  and geophysics. P.I.R.A.M.I.G. (Photography Infra-Red Atmosphere,
  Interplanetary Medium, Galaxies) is a wide field (10° and 40°) camera
  devoted to high sensitivity photographic photometry. The spectral
  range is limited to the visible and near-infrared (400-850 nm), the
  main advantage being to observe above the absorving and emitting layers
  of the atmosphere.

---------------------------------------------------------
Title: Electrostatic Charge of Interplanetary Dust Grains: New Results
Authors: Lamy, P. L.; Lefevre, J.; Millet, J.; Lafon, J. P.
1985ASSL..119..335L    Altcode: 1985IAUCo..85..335L; 1985piid.proc..335L
  A continuing program aimed at improving the determination of the charge
  of interplanetary as well as cosmic grains is presented. Recent data
  have been combined to generate two high-resolution solar spectra
  corresponding to the maximum and minimum of activity. The energy
  distribution of photoelectrons emitted by quartz grains under solar
  irradiation is calculated using the new laboratory measurements of
  Quemerais et al. (1986). Finally, the method of Lafon, Millet and Lamy
  (1981) is used to find the electrostatic potential of these grains.

---------------------------------------------------------
Title: A spectral photopolarimeter for Giotto: Halley optical probe
    experiment
Authors: Levasseur-Regourd, A. C.; Bertaux, J. L.; Dumont, R.;
   Festou, M. C.; Giese, R. H.; Giovane, G.; Weinberg, J. L.; Lamy, P.;
   Llebaria, A.
1984AdSpR...4i.287L    Altcode: 1984AdSpR...4..287L
  The Halley Optical Probe Experiment (HOPE) is designed to provide in
  situ photopolarimetric data on both the dust cloud and the gaseous
  atmosphere in Halley's coma. The optical probe concept is presented
  here, together with a description of the instrumentation and with the
  possibilities for cross-checks between HOPE results and those of other
  space and ground-based experiments.

---------------------------------------------------------
Title: The Betelgeuse shell : CCD/Fabry-Perot surface brightness
    photometry at K I lambda 7699A and mass loss.
Authors: Mauron, N.; Fort, B.; Querci, F.; Dreux, M.; Fauconnier,
   T.; Lamy, P.
1984A&A...130..341M    Altcode:
  Surface brightness photometric measurements of the Betelgeuse
  circumstellar shell at K I 7699 A were observed with a Fabry-Perot
  etalon and a CCD camera. Emission strength decreased as r exp -3.5 +
  or - 0.8, where r is the distance from the star. Also noted was that
  the emission strength, related to the mass-loss rate, and the slope
  of the decreasing intensity, related to the K I ionization and the
  density distribution, did not agree with values obtained by Honeycutt et
  al. (1980), but did concur with the model of Jura by Morris (1981). A
  mass-loss rate of 4 x 10 to the -6th solar mass/year was presented and
  the carbon scarcity in the shell was decreased to a factor of six. A
  slight departure from symmetry was found and tentatively attributed
  to photospheric brightness asymmetry.

---------------------------------------------------------
Title: Optical properties of cometary grains: a new model.
Authors: Lamy, P. L.; Perrin, J. M.
1983UppOR..25...49L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Nature, origin and evolution of interplanetary dust grains.
Authors: Lamy, P. L.
1983HiA.....6..427L    Altcode:
  The survey is based for the most part on studies carried out
  in recent years at the Laboratoire d'Astronomie Spatiale, in
  Marseille (France). The topics covered are the size distribution and
  physical properties of interplanetary dust grains, collisions among
  interplanetary dust grains, the implications for zodiacal light,
  and mass flux at 1 AU. A summary is given of the work presented by Le
  Sergeant d'Hendecourt and Lamy (1980). In discussing collisions among
  interplanetary dust grains, it is noted that certain investigators
  (Zook and Berg, 1975; Dohnanyi, 1976) have proposed that the population
  '2' of small, essentially submicronic grains could be the fragments of
  collisions between large grains ejected by radiation pressure, thereby
  creating an outflow of what are called 'beta-meteoroids' as detected
  by Pioneer 8 and 9. In another study by Le Sergeant d'Hendecourt and
  Lamy (1981), this mechanism was examined, and it was concluded that
  the calculated flux of fragments could not match by far the observed
  flux of submicronic grains.

---------------------------------------------------------
Title: Optical properties of rough cometary grains
Authors: Lamy, Ph. L.; Perrin, J. M.
1983acm..proc..273L    Altcode:
  The authors use their new model of light scattering by large rough
  particles to investigate the optical properties of cometary grains. The
  efficiency factor for extinction increases rapidly with increasing
  roughness while that for absorption remains fairly constant and while
  the ratio of radiation pressure to gravity decreases.

---------------------------------------------------------
Title: Widefield Ultraviolet Observations of Comet Halley with the
    FAUST SPACELAB-1 Instrument
Authors: Bowyer, S.; Courtes, G.; Kimble, R.; Deharveng, J. M.;
   Malina, R. F.; Lamy, P.
1983rrsb.conf..207B    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Large-scale Photographic Observations, Photometry, Colorimetry
    and Polarimetry of Cometary Tails
Authors: Lamy, P. L.; Koutchmy, S.
1982ncgb.conf..243L    Altcode: 1982gbhc.work..243L
  The use of large-scale photographic observations to characterize
  the dust tails of comets is discussed, with emphasis on plans being
  developed for observing Halley's Comet in 1986. The techniques used to
  investigate the geometric structure of the dust tail and its evolution
  (including detached structures, bursts, striae, and large-scale
  extensions), the integrated magnitude from blue to far IR, and color
  and polarization parameters are reviewed and illustrated with data
  and images from recent studies of other comets. The requirements
  for a network of identical cameras for Halley observations are
  examined: minimum 30-deg field of view, spectral coverage and filter
  separation, polarizers, calibration, color emulsions, and data-reduction
  schemes. Many of the problems inherent in ground observations programs
  could be avoided by using a space instrument such as the very-wide-field
  camera flown on the first Spacelab mission; this device is briefly
  described.

---------------------------------------------------------
Title: Wide field ultraviolet observations of Comet Halley with the
    FAUST Spacelab I instrument
Authors: Bowyer, S.; Kimble, R.; Malina, R. F.; Lamy, P.; Courtes,
   G.; Deharveng, J. M.
1982AdSpR...2l.207B    Altcode: 1982AdSpR...2..207B
  The wide field (7.5°), arc minute imaging, and spectroscopic
  capabilities of the Far Ultraviolet FAUST telescope which will be flown
  on Spacelab I can provide valuable information on Comet Halley. The
  use of the FAUST instrument in obtaining images of the hydrogen coma
  at 1216 Å, and in obtaining objective grating spectroscopy from
  1300-3300 Å of the comet and tail, are described. The FAUST images
  would provide large field of view data that are required for model
  calculations of gas production rates and the determination of scale
  lengths and lifetimes of ion species.

---------------------------------------------------------
Title: A coronographic mode for large telescopes.
Authors: Courtes, G.; Lamy, P.; Mauron, N.; Saisse, M.
1982ASSL...92...73C    Altcode: 1982IAUCo..67...73C; 1982ialo.coll...73C
  Lyot's coronographic technique of stray-light reduction has been applied
  to the Faint Object Camera of the Space Telescope. In addition, the
  application of the coronographic mode to the design of the Mount Chiran
  1-m and ESO 3.6-m Ritchey-Chretien telescopes has given new levels of
  performance in the detection of faint features in stellar and planetary
  observations. As an example, observations of a new satellite of Saturn,
  1980 S10 (Dione B), are examined.

---------------------------------------------------------
Title: An Opportunity for the Observations of Comets with Widefield
    Cameras Aboard the Salyut Space Station
Authors: Lamy, P. L.; Koutchmy, S.
1981motc.conf..190L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Collisional processes among interplanetary dust grains:
    An unlikely origin for the β meteoroids
Authors: Le Sergeant Dhendecourt, L. B.; Lamy, P. L.
1981Icar...47..270L    Altcode:
  The question of the collisional production of the β meteoroids is
  reexamined incorporating recent experimental results (A. Fugiwara,
  G. Kamimoto, A. Tsukamoto, 1977, Icarus31, 277-288). The collisional
  model yields a flux of fragments supported by the conservation of mass
  flux which does not account by far for the observed flux of submicron
  grains. Particles larger than about 100 μm will be destroyed by
  collisions inside 1 AU, well before they can get near the Sun. The
  existence of two independent populations of interplanetary dust grains
  as proposed by L. B. Le Sergeant and Ph. L. Lamy (1978, Nature266,
  822-824; 1980, Icarus43, 350-372) appears reinforced. It is proposed
  that the bulk of submicron grains does not necessarily travel in
  hyperbolic orbits and that β meteoroids may be a phenomenon—possibly
  transitory—of limited importance.

---------------------------------------------------------
Title: Observations of Saturn's outer ring and new satellites during
    the 1980 edge-on presentation
Authors: Lamy, P. L.; Mauron, N.
1981Icar...46..181L    Altcode:
  Observations of Saturn's satellites and external rings during the 1980
  edge-on presentation were obtained with a focal coronograph. A faint
  satellite traveling in the orbit of Dione and leading it by 72° has
  been detected, together with the two inner satellites already suspected
  (cf. J. W. Fountain and S. M. Larson, 1978,Icarus36, 92-106). The
  external ring has been observed on both east and west sides; it may
  extend up to ⋍8.3 Saturn radii, and appears structured.

---------------------------------------------------------
Title: Infrared Imaging and Speckle Observations with a TV Camera
Authors: Lamy, P.; Koutchmy, S.
1981Msngr..23....5L    Altcode:
  The lack of suitable two-dimensional detectors has been a major
  problem for infrared imaging in astronomy, and most results so far have
  been obtained by scanning the object with a single detector (e. g.,
  Terrile and Westphal,lcarus, 30, 730, 1977). The relative merit of
  both techniques was thoroughly investigated by Hall (Applied Optics,
  10, 838, 1971) who concluded that, below about 2.5 ~lm, camera tubes
  should be preferred to scanners. Besides, sufficiently long times
  required by the scanning technique are not always available for some
  astronomical applications. These considerations led us to acquire a
  standard television camera equipped with an infrared vidicon tube N156
  manufactured by Hamamatsu Co. (Japan).

---------------------------------------------------------
Title: Satellites of Saturn.
Authors: Lamy, P.
1981IAUC.3572....2L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Satellites of Saturn
Authors: Lamy, P.
1981IAUC.3574....2L    Altcode:
  P. Lamy, Laboratoire d'Astronomie Spatiale, Marseilles, telexes that
  further examination of plates taken at the Haute Provence Observatory
  (cf. IAUC 3463, 3491) reveals a new satellite, 1980 S 29, of mag ~
  14.5 to 15. On 1980 Mar. 16.126 UT, 1980 S 29 was located 19".75 east
  of Saturn. It may correspond to one or more of 1980 S 7, 1980 S 20,
  1980 S 23, 1980 S 26 or 1980 S 27. In addition, 1980 S 3 was measured
  at a position 22".7 west of Saturn on Mar. 16.9156.

---------------------------------------------------------
Title: Comets.
Authors: Festou, M. C.; Lamy, P.
1981Rech...12...46F    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Halley Optical Probe Experiment
Authors: Levasseur-Regourd, A. C.; Weinberg, J. L.; Giovane, F.;
   Schuerman, D. W.; Lamy, P.; Festou, M.; Bertaux, J. L.; Dumont, R.;
   Llebaria, A.; Giese, R. H.
1981giot.proc..121L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: On the electrostatic potential of interplanetary grains -
    Influence of the thermionic effect
Authors: Millet, J.; Lafon, J. P. L.; Lamy, P. L.
1980A&A....92....6M    Altcode:
  The general theory of the floating potential of a cosmic grain (Lafon
  et al. 1980) was used to investigate the importance of the thermionic
  emission for interplanetary iron and carbon grains in the vicinity of
  the sun. This emission prevents the potential of carbon grains from
  becoming strongly negative and allows small grains to exist in regions
  where they would otherwise be destroyed.

---------------------------------------------------------
Title: On the size distribution and physical properties of
    interplanetary dust grains
Authors: Le Sergeant D'Hendecourt, L. B.; Lamy, Ph. L.
1980Icar...43..350L    Altcode:
  This paper synthesizes information on the size distribution and
  physical properties of interplanetary dust grains obtained from
  analyses of lunar microcraters performed until 1979. The different
  aspects of these analyses (counting methods, simulation, calibrations)
  are summarized and a large amount of data is collected and discussed in
  order to clarify past contradictions. The number of small microcraters
  ( D<SUB>c</SUB> &lt; 5 μm) is found to be higher than previously
  derived and the ratio P/ D<SUB>c</SUB> (depth to crater diameter) to
  depend upon their sizes. All results converge to a two-component dust
  population: Population 1 consists principally of large grains ( d &gt;
  2 μm) with density typical of silicates while Population 2 consists of
  small grains ( d &lt; 2 μm) with higher density typical of iron, with
  a minor component of silicates. The conclusion appears to be further
  supported by spatial measurements and collection experiments. Fluffy
  grains of very low density (0.3 g/cm <SUP>3</SUP>) are probably not
  present to a large extent.

---------------------------------------------------------
Title: Satellites of Saturn
Authors: Lamy, P.; Mauron, N.
1980IAUC.3491....3L    Altcode:
  P. Lamy and N. Mauron, Laboratoire d'Astronomie Spatiale, Marseilles,
  send the following precise measurements of 1980 S 10 (cf. IAUC 3463)
  with respect to the center and equatorial plane of Saturn: Mar. 15.9528
  UT, +57".24 (east), -0".55 (south); 15.9851, +58".93, -0".38; 16.0236,
  +60".40, -0".37; 16.0892, +61".45, -0".57; 16.126, +61".65, -0".67. They
  also provide the measurements: 1966 S 2, Mar. 15.9851, 22".45 west;
  1980 S 3, Mar. 16.126, 19".75 east. They add that orbital analysis
  shows that 1980 S 10 (= 1980 S 6: cf. IAUC 3483) leads Saturn IV (Dione)
  by 72o.0. 1980 S 13 could not be found on plates taken on Mar. 15.9528
  and 16.962 on the assumption that it trails Saturn IV by 57o and was
  brighter than magnitude 18.

---------------------------------------------------------
Title: The New Satellite Dione B and Outer Ring of Saturn.
Authors: Lamy, P. L.; Mauron, N.
1980BAAS...12R.728L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Satellites of Saturn
Authors: Lecacheux, J.; Laques, P.; Wierick, G.; Lelievre, G.; Smith,
   B. A.; Blume, W. H.; Lamy, P.; Mauron, N.
1980IAUC.3483....1L    Altcode:
  J. Lecacheux, Observatoire de Meudon, reports the following analyses
  and further electronographic observations by P. Laques at Pic du Midi
  and by G. Wierick and G. Lelievre at Haute Provence of separations
  of satellites (+ = east, - = west) from Saturn's center: 1966 S 2 =
  1980 S 1 = 1980 S 2: Mar. 1.0488 UT, +22".16; 17.031, +21".83. Revised
  elements from the data on IAUC 3470-3474: greatest eastern elongation
  = 1980 Mar. 18.317 UT + light time + 0.0019 (U - 45o.6) + 0.69465
  E. The identities with 1979 S 7 and 1979 S 1 are invalid, the orbital
  longitude of 1966 S 2 at the time of the closest approach of Pioneer
  11 having been L = 121o +/- 3o. [Editorial Note. It now seems probable
  that the correct definition of 1966 S 2 is orbit 16 in the paper by
  Aksnes and Franklin (1978, Icarus 36, 107); see also Fountain and
  Larson (1978, ibid. 36, 92). The designation 1966 S 1 refers to
  an orbit with period 0.75 day, and no object with this period is
  now believed to exist.] 1980 S 3 = 1980 S 4 = 1980 S 5 = 1980 S 8
  (observation on IAUC 3463 only) = 1980 S 11 = 1980 S 15 = 1980 S 16 =
  1980 S 17 = 1980 S 19: Mar. 17.009 UT, -21".6; 18.040, +22".3. Elements
  (fitting the indicated observations with a standard deviation of 0".5):
  greatest eastern elongation = 1980 Mar. 18.645 UT + light time + 0.0019
  (U - 45o.6) + 0.6939 E. Other published observations (i.e., 1979 S 7,
  1980 S 7, 1980 S 9, 1980 S 18, 1980 S 20, 1980 S 21 and the IAUC 3466
  observation attributed to 1980 S 8 [here redesignated 1980 S 23: Ed.] do
  not fit any single circular solution. [Editorial Note. The suggestion
  that there exists a second satellite essentialy in the orbit of 1966
  S 2 and about 180o from it was privately made to the Central Bureau
  by B. A. Smith, University of Arizona, early in March. It is quite
  possible that 1980 S 3 = 1979 S 1, for which W. H. Blume has given the
  time of greatest western elongation (at Saturn) as 1979 Aug. 31.997 +/-
  0.004 UT. 1979 S 2 and 1979 S 4 can together presumably be related to
  1966 S 2 and 1980 S 3.] 1980 S 6 = 1980 S 10 = 1980 S 12 = 1980 S 14:
  Mar. 1.030 UT, +62".4; 1.049, +62".2; 1.099, +61".4; 1.131, +59".9
  (refinement to IAUC 3457). [Editorial Note. The suggestion that 1980 S
  6 = 1980 S 10 with period 2.75 days was included with the information
  provided by P. Lamy and N. Mauron for publication on IAUC 3463. Both
  Smith and Lecacheux have suggested that 1980 S 6 is associated with the
  triangular libration point leading Saturn IV (Dione). It is possible
  that 1980 S 13 is associated with the corresponding trailing point.]

---------------------------------------------------------
Title: Satellites of Saturn
Authors: Harris, A. W.; Gibson, J.; Lecacheux, J.; Fort, B.;
   Fauconnier, T.; Dreux, M.; Vapillon, L.; Laques, P.; Auge, A.; Despiau,
   R.; Lamy, P.; Mauron, N.
1980IAUC.3463....1H    Altcode:
  A. W. Harris, Jet Propulsion Laboratory, reports that observations
  by J. Gibson and himself with the 2.5-m reflector at Mount
  Wilson Observatory suggest that the satellite 1966 S 2 attained
  its greatest elongations from Saturn around the following times:
  Mar. 13.16 UT (west), 13.51 (east), 14.54 (west), 15.2 (west) and
  17.32 (west). Several other condensations, some of them obviously
  transient ring knots, were also noted. Three of them, each ~ 1 mag
  fainter than 1966 S 2, were somewhat more persistent and showed motion
  suggesting that they might be satellites. The designations, inferred
  times of greatest elongations and separations of these objects from
  Saturn were: 1980 S 7, Mar. 13.29, 23" east; 1980 S 8, Mar. 15.19, 24"
  east; 1980 S 9, Mar. 15.27, 25" west (clear of rings). J. Lecacheux,
  B. Fort, T. Fauconnier, M. Dreux and L. Vapillon, Meudon Observatory;
  and P. Laques, A. Auge and R. Despiau, Pic du Midi Observatory,
  communicate the following separations (uncertainty +/- 0".2) of 1966
  S 2 east (+) or west (-) of Saturn's center: Feb. 29.022 UT, -20".09;
  Mar. 1.0571, +21".76; 1.0575, +21".43; 1.0634, +20".78; 16.9439, +22";
  17.9661, -22".20; 18.0401, -24".64; 18.0443, -23".90; 18.0494, -23".33;
  18.1052, -17".74; 18.1065, -17".57. The observations were made using
  a Lallemand electronographic camera and a CCD camera on the 1.05-m
  Pic du Midi reflector. The best exposure (Mar. 18.0401) shows the
  starlike object very clearly detached from the A ring, brighter than
  Saturn VII (Hyperion) but fainter than Saturn I (Mimas); the inferred
  time of greatest western elongation is Mar. 18.017 UT. The following
  ephemeris has been deduced from these observations and those by Pascu
  and by Smith et al. on IAUC 3454, 3456 and 3457: greatest eastern
  elongation = 1980 Mar. 18.316 UT + light time + 0.0019 (U - 45o.6)
  + 0.69468 E. [Editorial Note. This formula is also in good agreement
  with the above observations by Harris and Gibson. On the other hand,
  it indicates a greatest eastern elongation on 1979 Dec. 9.3 UT,
  rather than Dec. 9.5 UT; cf. the observation by Mulholland on IAUC
  3430.] P. Lamy and N. Mauron, Laboratoire d'Astronomie Spatiale,
  Marseilles, report that observations with the Chiran 1-m telescope
  at the Haute Provence Observatory showed 1966 S 2 to be 24" west
  of Saturn's center on Mar. 15.983 UT. A faint nebulosity (mag ~ 16),
  possibly another satellite, was detected on several plates; this object,
  designated 1980 S 10, attained a maximum elongation of 61".4 west of
  Saturn's center on Mar. 16.024 UT (cf. 1980 S 6, IAUC 3457).

---------------------------------------------------------
Title: Collisions among Interplanetary Dust Grains
Authors: Le Sergeant, L. B.; Lamy, P. L.
1980IAUS...90..289L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Two-Dimensional Photographic Photometry of the Zodiacal Light
    from Spatial Observations
Authors: Lamy, P. L.; Llebaria, A.; Koutchmy, S.
1980IAUS...90...37L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The electrostatic potential of interplanetary grains
Authors: Lafon, J. P. J.; Lamy, P. L.; Millet, J. M.
1980IAUS...90..303L    Altcode:
  The plasma sheath and its bulk velocity are included as parameters
  for calculating the electrostatic potential of cosmic grains. The most
  important effects determining the charge of the grain to be considered
  in calculations are photoelectric emission and sticking of solar wind
  electrons and ions, except at small heliocentric distances. The results
  use parameters for two representative components of the solar wind and
  include the influence of bulk velocity which is important through the
  positive ions. The role of the solar wind appears clearly in the effect
  of its bulk velocity on the potential. The electrostatic potential is
  shown to increase slightly with increasing heliocentric distance and
  levels off at 1 AU, although thermionic emission will come into play
  and increase the potential.

---------------------------------------------------------
Title: Zodiacal light models with a bimodal population
Authors: Lamy, P. L.; Perrin, J. M.
1980IAUS...90...75L    Altcode:
  The compatibility of the observed properties of interplanetary
  dust grains in zodiacal light with a model made of two populations
  is investigated. Population 1 consists principally of large grains
  (with radius s greater than 2 microns) of density typical of silicates
  or chondritic materials in nearly circular orbit while Population 2
  consists of small grains (s less than 2 microns) with typically metallic
  densities (abt 8 g/cu cm) in hyperbolic orbits. The spatial densities
  and volume scattering functions (VSF) of the two populations are
  deduced from the observed brightness of the zodiacal light. Though no
  clear-cut conclusions are reached, some general trends are detected: (1)
  the VSF of the zodiacal light is entirely compatible with the spatial
  density of grains obtained from lunar and space measurements. (2)
  Under all circumstances, the contribution of Population 2 appears to
  be non-negligible. (3) A minimum albedo of 0.5 (probably unrealistic)
  is required in order to explain the observed VSF with Population 1 alone
  on the basis of the model of Fresnel reflection plus an isotropic term.

---------------------------------------------------------
Title: 2-D observations of IR-stellar speckles.
Authors: Lamy, P.; Koutchmy, S.
1979JOpt...10..331L    Altcode: 1979JOp....10..331L
  The first observations of speckle images of Alpha Orionis as obtained
  at the Cassegrain focus of the 193-cm Telescope of the Haute Provence
  Observatory using an IR-TV camera are discussed. The specific nature
  of the 2-micron images is outlined.

---------------------------------------------------------
Title: Radiation forces on small particles in the solar system
Authors: Burns, J. A.; Lamy, P. L.; Soter, S.
1979Icar...40....1B    Altcode:
  We present a new and more accurate expression for the radiation pressure
  and Poynting-Robertson drag forces; it is more complete than previous
  ones, which considered only perfectly absorbing particles or artificial
  scattering laws. Using a simple heuristic derivation, the equation of
  motion for a particle of mass m and geometrical cross section A, moving
  with velocity v through a radiation field of energy flux density S, is
  found to be (to terms of order v/c) m v˙ = ( SA/c)Q <SUB>pr</SUB>[(1
  - ṙ/c) Ŝ - v/c] , where Ŝ is a unit vector in the direction of
  the incident radiation, ṙ is the particle's radial velocity, and
  c is the speed of light; the radiation pressure efficiency factor
  Q<SUB>pr</SUB> ≡ Q<SUB>abs</SUB> + Q<SUB>sca</SUB>(1 - &lt;cos
  α&gt;), where Q<SUB>abs</SUB> and Q<SUB>sca</SUB> are the efficiency
  factors for absorption and scattering, and &lt;cos α&gt; accounts for
  the asymmetry of the scattered radiation. This result is confirmed by a
  new formal derivation applying special relativistic transformations for
  the incoming and outgoing energy and momentum as seen in the particle
  and solar frames of reference. Q<SUB>pr</SUB> is evaluated from Mie
  theory for small spherical particles with measured optical properties,
  irradiated by the actual solar spectrum. Of the eight materials studied,
  only for iron, magnetite , and graphite grains does the radiation
  pressure force exceed gravity and then just for sizes around 0.1 μm;
  very small particles are not easily blown out of the solar system
  nor are they rapidly dragged into the Sun by the Poynting-Robertson
  effect. The solar wind counterpart of the Poynting-Robertson drag may
  be effective, however, for these particles. The orbital consequences
  of these radiation forces-including ejection from the solar system
  by relatively small radiation pressures-and of the Poynting-Robertson
  drag are considered both for heliocentric and planetocentric orbiting
  particles. We discuss the coupling between the dynamics of particles
  and their sizes (which diminish due to sputtering and sublimation). A
  qualitative derivation is given for the differential Doppler effect,
  which occurs because the light received by an orbiting particle is
  slightly red-shifted by the solar rotation velocity when coming from
  the eastern hemisphere of the Sun but blue-shifted when from the western
  hemisphere; the ratio of this force to the Poynting-Robertson force is
  ( R <SUB>⊙</SUB>/r) <SUP>2</SUP>[( w <SUB>⊙</SUB>/n) - 1] , where
  R<SUB>⊙</SUB> and w<SUB>⊙</SUB> are the solar radius and spin rate,
  and n is the particle's mean motion. The Yarkovsky effect, caused by
  the asymmetry in the reradiated thermal emission of a rotating body, is
  also developed relying on new physical arguments. Throughout the paper,
  representative calculations use the physical and orbital properties
  of interplanetary dust, as known from various recent measurements.

---------------------------------------------------------
Title: Astronomical applications of infrared television imaging.
Authors: Lamy, P. L.; Nguyen-Trong, T.; Adjabschirzadeh, A.;
   Koutchmy, S.
1979A&A....77..257L    Altcode:
  Infrared imaging between 1 and 2.4 microns was realized with a
  television camera operated at the conventional video rate. A M2 star
  of visual magnitude 5.6 was detected at 1.2 and 1.6 microns. Alpha
  Ori was further observed at 2 microns and the corresponding smearing
  function was found to improve with increasing wavelength. The image
  structure (speckle) of Alpha Ori was visualized in the infrared and is
  briefly characterized as compared to the visible. Solar observations
  at 1.6 microns included direct imagery of sunspots and simultaneous
  spectrography of the photosphere and sunspot umbra. The Zeeman splitting
  of the 1.5648 microns Fe I line was observed and measurements are
  shown to be possible on processed CRT pictures.

---------------------------------------------------------
Title: Comet West 1975n. I. Observations near and after perihelion
    passage.
Authors: Koutchmy, S.; Coupiac, P.; Elmore, D.; Lamy, P.; Sevre, F.
1979A&A....72...45K    Altcode:
  Photographic observations of Comet West 1975n from a high altitude site
  are reported. A small value of the absolute magnitude of the Comet 1.5
  d after perihelion passage is deduced. Morphological characteristics
  of the strongly structured dust tail are obtained, using a statistical
  analysis based on the optical data processing of a transparency. The
  deduced two-dimensional power spectrum is considered. The temporal
  behavior of the main features of the tail is discussed using several
  selected pictures.

---------------------------------------------------------
Title: Comet West 1975n part II: study of the striated tail.
Authors: Lamy, P. L.; Koutchmy, S.
1979A&A....72...50L    Altcode:
  The dynamical evolution of the striae in the tails of comet West
  1975n is investigated. A synchrone-syndyne analysis of the overall
  tail structure is attempted, but it is found that the classical
  synchrone-syndyne description does not apply to the dynamical evolution
  of the striae. A subsequent examination of the main properties of
  the stria structure strongly suggests that all striae within a given
  tail appear to originate from a synchronic edge. A scenario for
  the formation of striae is proposed, according to which the bulk of
  the dust constituting a tail is released at or around perihelion and
  subsequently swept out under the influence of some unknown interaction
  that organizes the dust into narrow streaks, or striae. It is concluded
  that the unknown interaction involves the solar wind and a convected
  magnetic field.

---------------------------------------------------------
Title: Cometary Dust - Importance of Large-Scale and In-Situ
    Observations
Authors: Lamy, P. L.
1979comi.work..131L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Interplanetary dust: are there two independent populations?
Authors: Le Sergeant, L. B.; Lamy, P. L.
1978Natur.276..800L    Altcode:
  A RE-EXAMINATION of the information on the size distribution and
  physical properties of interplanetary dust grains as inferred from
  space measurements, particularly lunar microcraters, leads to the
  novel interpretation outlined here in terms of two independent
  populations. This hypothesis still suffers from uncertainties in
  existing data but should stimulate new experimental and theoretical
  work.

---------------------------------------------------------
Title: Photon Counting and Analog Television Systems with Digital
    Real Time Image Processing and Display
Authors: Cenalmor, V.; Lamy, Ph. L.; Perrin, J. M.; Nguyen-Trong, T.
1978A&A....69..411C    Altcode:
  Summary. For a photon counting television system (PCTS) and an analog
  television system (ATS), we developed a common acquisition, real-time
  processing and visualisation unit which is basically composed of a
  random access memory of 64 kilowords of 16 bits, a microprocessor, a
  television color display and a floppy disk recorder. Image processing is
  performed either by the microprocessor or by a minicomputer connected
  to the system. Preliminary results obtained at the telescope are
  reported. Key words: television photon counting image processing

---------------------------------------------------------
Title: Photometrical analysis of the June 30, 1973 solar corona.
Authors: Koutchmy, S.; Stellmacher, G.; Koutchmy, O.; Dzubenko, N. I.;
   Ivanchuk, V. I.; Popov, O. S.; Rubo, G. A.; Vsekhsviatskii, S. K.;
   Lamy, P.
1978A&A....69...35K    Altcode:
  In order to deduce reliable values of the K and F coronal, a method
  of photographic photometry has been applied to study compensated
  high-resolution pictures obtained during the June 30, 1973, solar
  total eclipse, including a color one. The correctly exposed images of
  calibration stars are used to obtain intensities in units of the mean
  brightness of the sun. An account is made, in both the blue and the
  red spectral ranges, for the sky background as well as for the coronal
  aureola effects. The N-polar and E-equatorial regions are shown to be
  relatively homogeneous; their intensities are especially studied in
  the radial direction and compared with published values of the K and F
  coronae. No flattening and no color effect are found in the inner part
  (distance less than 2.5 solar radii) of the F corona.

---------------------------------------------------------
Title: Propagating inhomogeneities in the dust tail of comet West 1975
Authors: Koutchmy, S.; Lamy, P.
1978Natur.273..522K    Altcode:
  COMET West has displayed some remarkable
  properties. Sekanina<SUP>1</SUP> has studied the multiple splitting
  of its nucleus and also discussed the strange structure of its
  dust tail. This tail is characterised by a system of bright bands
  which do not correspond to the true synchronous band<SUP>2</SUP> and
  which are shown by very few comets. We call these striae (striated
  tail) and to study them we have examined numerous original and
  duplicate pictures, and selected four observations (Table 1) which
  reveal that the morphology was relatively well conserved during the
  evolution of the dust tail over a period of more than 4 days. We have
  identified three striae (Fig. 1) which seem to propagate in space
  while retaining their basic form. This phenomenon is not unusual in
  plasmas, such as gas tails of comets<SUP>3</SUP> or streamers in the
  solar K-corona<SUP>4,5</SUP>. However, this is apparently the first
  time that it has been observed in dust `clouds'. These striae, which we
  describe here, are made of dust grains which can be readily demonstrated
  by the wide-field colour photographs made by comet observers: the gas
  tail (type I) appears distinctly blue because of CN emission and is
  directly in the anti-solar direction as well as being well separated
  from the large dust tail (type II) which has a neutral colour.

---------------------------------------------------------
Title: Optical properties of silicates in the far ultraviolet
Authors: Lamy, P. L.
1978Icar...34...68L    Altcode:
  Near-normal incidence reflectance measurements in the interval 1026-1640
  Å were performed on four silicates already studied in the visible and
  infrared by Pollack et al. (1973). We use a Kramers-Kronig analysis
  of these data to calculate the complex index of refraction m = n -
  ik. New transmission measurements improve the determination of k in
  the interval 2500-4500 Å, except for andesite, which is more opaque
  than found by Pollack et al.

---------------------------------------------------------
Title: Workshop on cometary missions. ESOC Darmstadt, 17 - 19
    April 1978. Chairmen's summaries and extended abstracts of invited
    contributions.
Authors: Arpigny, C.; Bertaux, J. L.; Bodechtel, J.; Dalmann, B. -K.;
   Fechtig, H.; Festou, M.; Giese, R. H.; Grün, E.; Haser, L.; Hughes,
   D. W.; Ip, W. -H.; Jockers, K.; Keller, H. U.; Keppler, E.; Kissel,
   J.; Koutchmy, S.; Krankowsky, D.; Lämmerzahl, P.; Lamy, P. L.;
   Levasseur-Regourd, A. -C.; Lukoshhus, D.; Malaise, D.; Mariani, F.;
   Michel, K. W.; Neukum, G.; Orfei, R.; Rosenbauer, H.; Röser, S.;
   Schlude, F.; Schmidt, H. U.; Schubart, J.; Schwehm, G. H.; Sieber,
   A.; Wänke, H.; Wallis, M. K.; Zerull, R. H.
1978wocm.book.....A    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Radiation pressure and Poynting-Robertson drag for small
    spherical particles.
Authors: Soter, S.; Burns, J. A.; Lamy, P. L.
1977cami.coll..121S    Altcode: 1977IAUCo..39..121S
  Robertson's expression for the velocity-dependent effect of solar
  radiation on the motion of small particles is difficult because of its
  dependence on relativistic considerations, and it is also deficient in
  that it assumes perfectly absorbing particles. The present paper gives
  a heuristic derivation of the Poynting-Robertson effect. Robertson's
  expression for perfectly absorbing particles is obtained but on a
  much simpler physical basis, and an expression is also obtained for a
  particle that in general scatters, transmits, and absorbs light. Some
  numerical results on the solar radiation forces felt by small particles
  of cosmochemically important compositions are given.

---------------------------------------------------------
Title: Traitement des Images TÉLÉVISION - Application à une
    CAMéRA Infra Rouge
Authors: Lamy, P. L.; Nguyen-Trong, T.; Perrin, J. M.
1977aaid.coll...17L    Altcode: 1977IAUCo..40...17L
  No abstract at ADS

---------------------------------------------------------
Title: A Corrected Derivation of the Poynting-Robertson Effect
Authors: Burns, J. A.; Soter, S.; Lamy, P. L.
1976BAAS....8..434B    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Poynting-Robertson effect for small spherical particles.
Authors: Burns, J. A.; Soter, S.; Lamy, P. L.
1976BAAS....8..471B    Altcode:
  No abstract at ADS

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Title: Study of the Anti-Tail of Comet Kohoutek from an Observation
    on 17 January 1974
Authors: Lamy, Ph. L.; Koutchmy, S.
1976LNP....48..343L    Altcode: 1976IAUCo..31..343L
  As part of our program of observation of Comet Kohoutek at Pic-du-Midi
  observatory, we obtained, on January 17.8 UT, 1974 a photograph in
  polarized light showing dramatically the (dust) antitail extending
  for almost 1° from the Comet's head (reported in Sky and Telescope,
  June 1974); indeed the comet is visible in polarized light further
  away than in total light as noticed by Weinberg and Beeson (IAU
  Colloquium No. 25, 1974) for Comet Ikeya-Seki. A photometric
  and polarimetric study was performed (Bücher, A., Robley, R.,
  and Koutchmy, S., 1975, Astron. Astrophys. 39, 289) showing that
  the anti-tail is strongly polarized (up to 50 %). These large
  degrees of polarization are of the same order of magnitude as those
  reported for the tail of Comet Ikeya-Seki by Matjagin Sabitov and
  Kharitonov (1967, Astron. Zh. 44, 1075) and by Weinberg and Beeson
  (op. cit.). As discussed by these latter authors, particle alignment
  is precluded as a significant contributor to polarization in the tail
  of comets. Polarization by large spheres as obtained from the Fresnel
  reflection coefficients applies only in the case of perfect surface,
  a circumstance very unlikely in interplanetary space; the scattering
  is in fact controlled by the surface microstructures (Van de Hulst,
  private communication). Therefore we hypothesized that submicronic
  grains should play an important role in the anti-tail. The classical
  method of Finson and Probstein (1968, Astrophys. J. 154, 327, 353)
  was used to draw the sky plane view of the syndynes for the day of
  observation. Since the ratio β of the radiation pressure force to
  the gravitational attraction is proportional to the third power of
  the grains' radius s for ≲z 0.1 μ, submicronic grains with typical
  radii of 0.02 μ may indeed be present in the anti-tail and provide a
  straight-forward explanation of the observed polarization. This size
  is of the same order of magnitude as that inferred for interstellar
  grains which may well be embedded in the comet's nucleus as well as
  meteorites for which there exists good evidence. Our conclusion does
  not rule out the presence of millimeter-size grains as proposed by
  Sekanina and Gary and O'Dell in their preliminary investigations (1974,
  Icarus 23, 502, 519) which did not take into account the polarimetric
  result; such grains may well coexist with the submicronic ones. Finally,
  the line of maximum intensity is close to a synchrone corresponding to
  a time of emission 100 days before perihelion passage. This supports
  the synchronic formation of anomalous tails and possibly of tails as
  proposed by Vsekhsvyatsky (1932, Astron. Zh. 9, 166).

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Title: Temperature Distribution and Lifetime of Interplanetary
    Ice Grains
Authors: Lamy, P.; Jousselme, M. F.
1976LNP....48..443L    Altcode: 1976IAUCo..31..443L
  An improved solution for the temperature distribution of interplanetary
  ice grains is presented using the refractive index measured at 100
  K. The efficiency factors for absorption are obtained from Mie theory,
  and the calculation is carried out for micron- and submicron-size
  grains at 50, 100 and 150 K. Corresponding lifetimes are given.

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Title: Orbital Evolution of Circum-Solar Dust Grains
Authors: Lamy, P.
1976LNP....48..437L    Altcode: 1976IAUCo..31..437L
  The orbital evolution of circumsolar dust grains is obtained by
  numerical integration of the equations of motion which includes
  the grains' interactions with the solar radiation field and the
  solar wind. A previous solution is improved by avoiding a classical
  approximation for the Poynting-Robertson term, leading to an important
  revision of the orbital behavior. Results are presented for obsidian
  grains whose inward spiraling is stopped by the effect of sublimation.

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Title: Study of the Inner Satellites of Saturn by Photographic
    Photometry
Authors: Koutchmy, S.; Lamy, P. L.
1975Icar...25..459K    Altcode:
  Good photographs of Saturn and its five inner satellites were obtained
  on January 2, 1974 with the 105 cm telescope at Pic du Midi Observatory
  with exposure times of 45 sec. The spread function is constant over the
  field, and isotropic. The true photometric profiles of the satellites
  are obtained after deriving a model for the stray light coming from the
  rings. The magnitudes, computed by integration, are in good agreement
  with published values except for Mimas, which is nearly one magnitude
  fainter then previously believed.

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Title: On the dynamics of interplanetary dust grains
Authors: Lamy, Philippe Louis
1975PhDT.......173L    Altcode:
  No abstract at ADS

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Title: On the Dynamics of Interplanetary Dust Grains.
Authors: Lamy, P. L.
1975PhDT.........6L    Altcode:
  The interaction of spherical grains of various materials whose radii lie
  in the micronic and submicronic range with the interplanetary medium
  is solved. This includes: (1) interaction with the solar radiation
  field which is solved using Mie scattering theory and taking into
  account the precise dependence of optical properties upon wavelength;
  (2) interaction with solar wind considering corpuscular tangential
  drag; and (3) interaction with the interplanetary magnetic field in
  terms of a diffusion or random walk through a series of electromagnetic
  scatterings. Numerical results for these interactions span in the entire
  solar system with elliptical orbits of grains of various materials and
  sizes and provide a clear global picture of dust grain interactions
  that includes grain dynamic considerations.

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Title: Interaction of interplanetary dust grains with the solar
    radiation field.
Authors: Lamy, P. L.
1974A&A....35..197L    Altcode:
  The interaction of interplanetary dust grains with the solar radiation
  field is investigated for micronic and submicronic spheres of quartz,
  obsidian, andesite, ice, and iron. The dependence of the complex
  indices of refraction on wavelength was taken into account using Mie
  theory to obtain the efficiency factors for absorption and radiation
  pressure. The temperature distributions differ markedly from past
  results, and show that silicate grains can come very close to the sun,
  thus justifying the existence of a dusty component of the solar corona
  up to approximately 2 solar radii. Improved vapor pressure formulas
  yield increased lifetimes for interplanetary grains. It is shown that
  the onset of rapid destruction by sublimation is extremely sudden and
  has a well-defined location which depends upon the absorption character
  of the grains' material. The radiation pressure force never exceeds
  the gravitational force for silicates and ice.

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Title: The Dynamics of Circum-solar Dust Grains
Authors: Lamy, Ph. L.
1974A&A....33..191L    Altcode:
  Summary. The inward spiraling of interplanetary dust grains under
  the Poynting-Robertson and corpuscular pressure drags is shown to be
  either counterbalanced or reduced by the effect of the net increase
  of the radiation pressure force caused by the decrease of the grains'
  radii when sublimating. Precise trajectories, obtained for the first
  time, show that silicate grains remain in the vicinity of the Sun
  where they describe an impressive number of orbits. Dynamical dust4ree
  zones are clearly established and the location of regions of probable
  concentration are predicted; infrared emission spectra show remarkable
  features which can serve as signatures for the nature of the dust. It is
  also concluded that grains whose radii are less than about 0.2 m play
  a negligible r6le in the F-corona. Key words: interplanetary dust -
  F-corona - circumstellar envelopes - infrared spectrum

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Title: Infrared Photometry of the Outer Corona.
Authors: Lamy, Ph. L.; Koutchmy, S.
1974BAAS....6..311L    Altcode:
  No abstract at ADS