MDM Observatory 1.3m Telescope Observer's Report for 2003 Apr 20

Observer(s): S. Lepine, D. McCourt
Institution(s): MkIII Spectrograph

Instrument: MkIII Sectrograph + Wilbur

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

Seeing and Weather:
   Beg: Seeing >2.0 arcsec, Clear, Winds Calm
   Mid: Seeing >2.0 arcsec, Clear, Winds Calm
   End: Seeing >2.0 arcsec, Clear, Winds Calm

Observing Summary:

Not very ood seeing, but otherwise clear night.
Got spectra of 38 candidate nearby stars.

An update on the North-South  jerky motion  (see recent
trouble reports):
From what we could observe, the erratic N/S motion occurs
only when the telescope is directly facing the wind, which
explains why it occured mainly for low declination targets 
(winds generally blows from south-west or south-east). The
wind doesn't have to be very strong; we saw erratic N/S 
for wind speeds down to only 10 mph.
We have two solutions to avoid this problem. (1) Avoid
observing targets with the telescope facing the wind. If 
however your target happens to be in the direction the wind 
blows from and you do witness the N/S erratice motion (2) move 
the *dome* by 10-20 degrees or more to try and shield the 
telescope from the wind, this works best when observing at 
low airmass because the dome can be rotated by large amounts
without blocking the field of view.

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Submitted on 2003 Apr 21 [5:35:09]