Saturday night, April 4, was to be the first scheduled Public Night at the Observatory of the year not canceled by weather conditions. As forecast, the skies cleared and promised to cooperate for the night's event giving us fair seeing and temperatures in the mid-30s. Because of previous cancellations the Open Night was to serve as our official Saturn Observation Campaign event for the spring and we registered as a local site for the global "100 Hours of Astronomy" which is a part of the International Year of Astronomy observance.
Despite clear skies our events nearly did not happen. Pulling the ropes to open the observatory's dome shutter I head a loud squawk echo through the chamber -- the shutter had jammed for some reason and would not open fully and would not close. Repeated efforts finally resulted in the shutter opening all the way and we were free to see the sky.
The night saw 26 visitors between 9:00 and 11:00 and they were treated to superb views of the Earth's Moon. As usual the old nine-inch scope excelled at lunar landscapes but the Moon was very high in the sky --not far from the zenith-- and the telescope was not tracking well. We settled for moderate magnification (133X) and enjoyed nearly three-dimensional viewing of Mare Imbrium's crater-marked lava expanses. Wrinkled crater walls, mountain ranges, and long, low, lines of hills looking like frozen ripples in hardened plaster were seen vividly. Views of Saturn were also quite good: the rings tipped towards us at only about three degrees (minimum tilt was reached in January but we missed that). Moments of very good seeing revealed a slight shadow across the planetary disk cast by the rings and a hint of gap between the planet's limb and the inner rings. A special treat was the sight of four of Saturn's moons and, over the course of the evening, noting their changing positions relative to each other and to their planet. Galileo, 400 years ago, never saw the Moon or Saturn a fraction so well as we did. He was, however, very meticulous and a skilled observer of what he could see. The Moon, while beautiful to look at, also lit our less-than-perfectly transparent skies causing quite a bit of glow so we confined ourselves to viewing only it and Saturn. The last visitors departed at about 11:10 PM.
All was routine as I began closing up until I attempted to close the dome. Squawk, boom! The shutter stalled and jammed again on its tracks. This time, however, it was stuck. After many attempts with the ropes I climbed into the opening. I found one of the lower wheels on the shutter had derailed so I lifted the shutter back on to the track. Not enough! The main problem was with the track at the top of the dome! There's no way to reach that point without scaffolds or ladders. It was going on midnight and I didn't know what to do but to keep trying. If anyone was watching from outside it must have been quite a sight... the silhouette of a man in the aperture, bright lights on inside an observatory dome, pushing and pulling and shaking the shutter, until finally it settled into its closed position. Tired, sore, and worried, I shut off the lights, locked up, and headed home at about 12:30 EDT. What a night!
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