MDM Observatory 2.4m Telescope Observer's Report for 2007 Jan 27

Observer(s): John Thorstensen
Institution(s): Dartmouth

Instrument: Echelle CCD direct + 2in FW

Worked for 13 hours (all night)
Conditions were Photometric most of the night.
No equipment or software problems were encountered.

Seeing and Weather:
   Beg: Seeing 0.9 arcsec, Clear, Winds Light & Variable
   Mid: Seeing 0.6 arcsec, Clear, Winds Light & Variable
   End: Seeing 0.7 arcsec, Clear, Winds Light & Variable

Observing Summary:

Another excellent night.  There may have been a little high cloud
toward the end, but for the most part it was photometric under
enough moon so one could tell.  But what was really astonishing
was the seeing -- I've observed here for 25 years, and I cannot
recall any better.  I had a series of three-minute unguided
images that all measured up less than 0.6 arcseconds, with one
of them approaching 0.5 arcseconds FWHM.  Oddly, the mirror was
about 1 C warmer than ambient -- the mirror A/C is down for 
repairs -- and there was a slight breeze.  What may have done it
was the very consistent temperature, which didn't move more
than 0.5 C for several hours.  Whatever the reason, I'll take
it.

------------------------------

Submitted on 2007 Jan 28 [7:28:32]