DOT news

• no DOT news anymore, unfortunately.   The DOT is in principle available but remains mothballed until a revival gets funded.  That requires manpower (two to four salaries) plus 50-100 kEuro/year for running costs.  You are very welcome to get yourself a very nice solar telescope named after you!

• January 2012: Utrecht astronomy is gone.  The DOT is mothballed until somebody supplies funding for restarting observations.  The DOT website is now here. The DOT database is now at ftp://dotdb.strw.leidenuniv.nl with the chronological data index at https://dotdb.strw.leidenuniv.nl/DOT, the search engine at https://dotdb.strw.leidenuniv.nl/search, and the observing wiki at https://dotdb.strw.leidenuniv.nl/wiki.

• December 2011: Utrecht University terminates its astronomy program (which it started back in 1642, the year Isaac Newton was born).  The DOT database server moves to Leiden Obervatory, with the group of C.U. Keller including F.C.M. Bettonvil.  The future of the DOT is highly uncertain, but in principle the DOT remains available for self-funded external usage.

• Spring 2011: F.C.M. Bettonvil took up a job with NOVA and G. Sliepen moved to the SST.

• December 2010: USA/NSF-funded Helio Research concluded a successful year of gathering many filament and prominence observations with the DOT (over 70 Terabyte in total).  Quick-look frame-select movies are available in the DOT database.  Selected image sequences are under speckle reconstruction.

• July 2010: addition of a speckle demonstration movie comparing full speckle reconstruction with Keller - von der Lühe restoration and with frame selection.  See DOT speckle modes.

• Spring 2010: the start of USA/NSF-funded Helio Research campaigns triggered much improvement of the DOT observers wiki by G. Sliepen.

• October 2009: EC-funded DOT observer V. Olshevsky has speckle-reconstructed the DOT observations from 2008, reducing the large backlog that was built up after P. Sütterlin moved to the SST. 

• June 2009: the tunable narrow-band Lyot filter for Ba II 4554, built by V. Skomorovsky and colleagues at Irkutsk, finally came on line after extensive refurbishment and installation funded by INTAS.  Due to poor camera characteristics the images are noisy but still suited to make Dopplergrams.  You are welcome to supply a better camera!

• Autumn 2008: DOT observers wiki started by EC-funded DOT observer S. Vargas Dominguez.

• February 2008: DOT database search engine constructed by EC-funded Tim van Werkhoven.

• January 1, 2008: our major sponsors during the past years (UU Dept. Physics & Astronomy, NWO, NOVA) have terminated their contributions.  In consequence, Dr. P. Sütterlin moved to the SST and Ir. F.C.M. Bettonvil transited to design studies for the EST.  Nevertheless, DOT availability is continued partially, on a much reduced budget.  Partnerships bringing external funding for on-site observers and telescope upgrades are welcome.

• April 2007: new DOT poster designed by Frans Snik.

• October 2006: invitation to join in a major DOT upgrade, with various design options.

• September 2004: the Halpha filter was installed in the DOT top, pointed at AR10675, and produced a beautiful Halpha mosaic of active region AR10675 with a monochrome morph and a false-color morph sequentially showing the photosphere sampled in the G band, the low chromosphere sampled simultaneously in Ca II H, and the high chromosphere sampled simultaneously in Halpha.  A simple version served as Astronomy Picture of the Day and was pictured in the Frankfurter Allgemeine.

• July 2004: start of "Open DOT" time allocation to external observers.

• June 8, 2004: the first Venus transit in 122 years was recorded beautifully by the DOT.

• June 18, 2003: a short near-limb Ca II H movie showing "straws”, with a companion four-panel movie showing the same scene also in the blue continuum, G band, and the wing of Ca II H. 

• February 23, 2000:   this sunspot movie was posted as the first video on Astronomy Picture of the Day.

• October 31, 1997:  DOT First Light Ceremony featuring Crown Prince Willem-Alexander, Science Minister Jo Ritzen and many other dignitaries.  More photographs here.