Log, Oct 26, 2001

13 people. When I arrived we had a great many thick but low lying clouds. These generate just after sunset and usually disapate by 9 to 10 PM. However, these seemed a bit more sincere than most of the evening clouds. I got a call from a lady with two daughters who asked if we were open. I said yes - provisionally. Some after a number of folks arrived including a number of our docents. Joe had sent a message saying he couldn't be here and Doug was having car problems. However enough other docents were around to keep us in operations if it cleared.

Well the lady and her daughters arrived and we showed them the Moon in gaps in the clouds which were by now very infrequent. I sawed the seven year old girl things on the computer and even had her help close up the dome against what was obviously going to be a shower. In any case, it was 8 PM and tonight was the first night of the fall astronomy classes. We traipsed over to the Nature Center and I was surprized to not only have the enrolled class members but a whole squad of docents. Oh well, I thought, they might as well stay warm because outside is useless. The class soon was underway and a couple of hours past. Several of the docents were where they could see the sky. I figured they would make a wild bolt for the door if the clouds rolled away but unknown to me the clouds left and they stayed!

Now between you, me and the gatepost, I think I can give at least a moderately interesting and information packed introductory astronomy class. After a half century, I better have learned a thing or two. However, in a race between me and clear skies, I would be the first to bolt if I was just sitting in on a class I know as well as the instructor. So it can as quite a surprize to find the night was a good clear night. By 10:45 we were back in business at what we do best. Now I didn't see any cars pull up and away while we were inside. If anyone came and left I hope you'll come back soon. We really didn't know how much things had cleared.

We had been looking at the Moon early on, as the only possible target in the occasional breaks in the clouds. Now the Moon limited us to bright targets. Saturn was our first choice. We played with the software to show visitors the seasons of Saturn over a 30 year period (one Saturn year). Sky Chart III does a spectacular job of tilting the planet so you see the rings edge on to wide. However Saturn itself was better. It wasn't very stable but still well worth more than a cursory glance.

M42 became an eyetest tonight. The four bright stars [A, B, C, and D] of the Trapezium and the nebulosity were clear and sharp with only moments of watery wobbles and traces of unwanted color. Star E was visible for long stable periods with F in and out. Star G was never seen, the only report of it put it in the wrong place and I suspect the viewer saw a telescope ghost, an internal reflection in the eyepiece. We turned to Rigil, expecting a big watery image. We wondered if we would be able to see Rigil B in the glare of a wobbling Rigil A. Well Rigel A was a dazzingly scintillating blob, but Rigel B was rock steady! I have no idea how a big bright star can wobble, and a dim star arcseconds away can be steady but here was proof.

I turned the telescope on β Eridani, for a CURSAry view [bad pun, β Eridini's laten name is CURSA]. It is a double. I told everyone that it was easily split, but person after person couldn't split it until I told them the trick. Beta Eridani is an extremely wide double, so wide that the second star appears to just be a background star! In fact it was farther from the primary that two and a half Jupiter widths.

I turned the scope to 12 Monoceros which is the brightest star in an open cluster inside the Rosette Nebula. The Rosette Nebula NGC2238 actually holds two open clusters NGC2252 and NGC2244. The open clusters were clear and reasonably easy to see but the Moon washed out the Rosette.

The night The remainder of the night was spent on Jupiter watching a double shadow on the surface and the start of a transit of Io with Europa close behind. We tried various filters but we could not bring out the red spot which had been easy to see last week. Several of us had to leave early so this was our swan song tonight. By now it was hard to go. The Moon was low and would set in another hour, the air was finally still and seeing was becoming excellent.

-Les Coleman

Leslie Coleman
Leslie Coleman
Entry Date:
Oct 26, 2001
Published Under:
Leslie Coleman's Log
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