Log, Sep 24, 1999

Friday: 53 people. As we knew, the brightness of the Moon dictated much of our viewing tonight. The air was initially moderately unstable but improved throughout the night. By the middle of the night, there was little or no twinkling in the stars and the Moon was so crisply clear that many areas looked as sharp to the eye as they would through a good telescope.

Joe was the first to arrive and by the time others came, he had the dome rotation switch apart and was busily drawing a chart of the various switch and motor connectors. Luckily, the wiring (as is standard) is color coded (white, black, orange, blue, green) and the connectors are labeled, making the charting task much surer and easier. When we get though, we will have wired the dome rotation switch in parallel with two "FireCracker" remote switches that will respond to commands issued by both a hand held remote and a simulation of a hand held remote on the computer. Once in place, we will be able to control the dome rotation from anywhere in the dome, and if we ever connect the PC to the Internet, actually control the dome from any place with Internet connectivity.

Rob arrived with the 6" Meade nicely restored. He set it up on the outside pad and it worked very well. It produced nice images and tracked fairly well. Getting a good polar alignment on this scope is not as easy as some others because the axis lacks a sighting mechanism. Throughout the evening Rob picked out celestial objects to compliment the targets in the 16".

We had a fine group of visitors ranging from toddlers to elders just the very people we have always said we served. Some of the kids were wonderfully knowledgeable about the sky. One little girl had gone to a week long summer camp for astronomy this summer. She has told her folks she wants to be a ballerina and an astronaut more power to her! As usual we got our normal eclectic mixture of people who were very much up on astronomy to people who were first or second timers. As always, the staff made sure everyone knew that they were more than welcome each and every subsequent Friday evening.

I mounted my big binoculars on a tripod, planted them squarely in the middle of the walkway, and all but forced people to look at things through them. I am off on one of my campaigns to convince people not to buy a "gimcrack telescope" before they have had a chance to investigate the wonders available though something as common and modest as a 7x35 binoculars. I was very pleased to note that earlier exhortations had been heeded and that several people arrived with binoculars strapped about their necks.

Joe, Dave, Allyson and Art spent most of the night inside with our visitors. The 16" was primarily focused on the bright objects. The Moon, as always, was a target people wanted to see. We talked at length about crater formation, the early solar system, the ring walls, the central ejecta and mares. Saturn and Jupiter were exceedingly clear if somewhat low contrast due to the bright Moon fairly close by. Casini's Division was as crisp as if it had been drawn with a scribing tool. Cloud structure on Saturn was evident. There was much debate as to whether we could/could not see Mimas. Mimas was very close to the Ring and hard to pick up in the glare. The staff decided that the answer was some people glimpsed Mimas and others didn't. So everybody was right. Jupiter was very clear. Not only could we see multiple bands, but we could distinctly see swirls within the larger bands. The Galilean Moons were bright and easy to pick up although Callisto would disappear at higher powers.

Though out the night, the 16" seem to track badly and it did not seem to find objects well. We attributed this problem to a poor alignment but things got steadily worse. When we went to check what was the matter, the telescope made a nasty vibratory sound. We opened the declination drive panel and examined everything. Everything was well greased and nothing showed any signs of wear. We discovered a small drop of bluish fluid which may/may not have been there all along. We gently moved the telescope and could not find anything wrong. Once we reassembled the scope, the vibration was gone. I hypothesized that the declination brake might not have been completely screwed in place. We realigned the scope and for a while we got extremely good tracking and placement. Then slowly the tracking problem came back. We are going to have to see exactly what is slipping when we are not so tired. Perhaps it is as simple as a loosely fitting belt or an incorrect piece of data (time, location or what have you).

-Les Coleman

Leslie Coleman
Leslie Coleman
Entry Date:
Sep 24, 1999
Published Under:
Leslie Coleman's Log
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