MDM Observatory 2.4m Telescope Observer's Report for 2007 Jul 19

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

Instrument: Modspec + Echelle CCD

Worked for 2 hours (last half of the night)
Conditions were Mixed most of the night.
No equipment or software problems were encountered.

Seeing and Weather:
   Clouds from start until 2:15.
   Beg: Overcast, Winds High, lightning, rain
   Mid: Overcast, Winds Moderate, rain til midnight
   End: Seeing 2 arcsec, Patchy Clouds, Winds Light & Variable

Observing Summary:

The night began with an astonishing display of lightning as a 
huge black cloud complex -- many, many miles across -- bore
down on us from the East.  I have seldom, if ever, seen so 
much lighting -- because it was visible over such large 
distances at night, it seemed as if the whole sky was continuously
lit. However, the lightning never came near to striking the 
observatory (though we were of course shut down as a precaution).
I thought maybe I'd see the four horsemen coming, or maybe the
Rapture, but these didn't happen.

It proceeded to rain off and on until midnight; I don't think 
we were ever in the middle of a major deluge, but it seemed to 
soak everything pretty well.  Electrical activity died down 
enough after midnight to bring the computers back up, and I was
astonished when it cleared off around 2:15 AM, with humidity
far below the limit.  I opened and got some data; there were
still patchy clouds, and the seeing wasn't good, but the data
appear usable.  I closed a tad early because of increasing 
cloud in twilight.

The commercial power was up and down during the storm, and
the generator would start and stop.  The A/C main breaker
did trip during the day -- I didn't catch it until after
dinner -- but through all this (literal) Sturm und Drang,
it never tripped, evidently because the system was shut down.
So power glitches only trip the A/C breaker if the system is
under load at the time.  This may be old news but seemed worth
a remark.

The new shutter works fine, but like the old one, it needed
a power-cycle of the uniblitz controller before it worked 
right, so whatever flaw is causing this behavior seems to be in 
the controller and not in the shutter.  

I'd like NOT to change to direct tomorrow; the forecast
is dreadful, so the likelihood of getting conditions good 
enough to use for the parallax work is near zero, and there 
are still some loose ends in the spectroscopic program that 
could be tied up with short observations late at night.  So 
just leave the spectrograph on for the duration, please.

No rats sighted!  

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Submitted on 2007 Jul 20 [4:30:06]