MDM Observatory 2.4m Telescope Observer's Report for 2008 Feb 25

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

Instrument: Echelle CCD direct + 4 in FW

Worked for 10 hours (most of the night)
Conditions were Mixed most of the night.
No equipment or software problems were encountered.

Seeing and Weather:
   Beg: Seeing 1.2 arcsec, Cirrus, Winds Moderate
   Mid: Seeing 1.5 arcsec, Clear, Winds High
   End: Seeing 5 arcsec, Clear, Winds High

Observing Summary:

Well, most of tonight was clear -- photometric in fact -- but 
around midnight the wind started picking up and the seeing
deteriorated until it was -- well -- pick your adjective -- 
4 or 5 arcseconds much of the time.  Parallaxes were impossible,
so I collected a time series for a while.  When that object
went away, I poked around a bit and finally closed an hour
before the beginning of twilight.  The seeing was so bad I 
couldn't even do photometric standards, because I'd have had to
use a huge aperture to catch all the light.

Two minor glitches: (1) the power dropped out during the day,
which caused the mirror A/C breaker to trip.  I overlooked
this until just before dinner, so the mirror was a bit 
warmer than I'd have liked.  I'm sure that didn't cause the
wretched seeing, though -- it was much worse than that.  
My fault for missing the problem, but it would also be good
if staff would check the breaker if they're aware that the 
power has tripped -- most observers sleep later than I do and 
aren't going to catch this until they get up.
(2) mirror A/C display is showing spurious spikes in the 
ambient temperature, as if there's a bad connection.

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Submitted on 2008 Feb 26 [6:19:36]