Log, Aug 26, 2005

72+ people. The evening started out with a fair number of broken clouds and cloudy wisps but they evaporated and the sky grew darker and clearer. A fair amount of turbulence remained near the horizon but above 20 degrees the sky was stable and lovely. My own personal measure of the sky placed it at between 6 and 7 after the clouds evaporated, and may have edged up to 7 later on. I could easily see 4th magnitude extended objects by eye. 5th magnitude stars were easy to pick up and you could see 6th magnitude stars if you knew just where to look. The Milky Way showed a great deal of detail. I was able to point out the arm structure to visitors who never had seen any detail in this glowing band before tonight. For those of you who haven't encountered my totally subjective scale, it runs from 0 to 10 where 0 is "you can't see the clouds because the fog is too thick" to 10 which is what the Hubble Space Telescope sees. I have seen perhaps a couple of 9 nights in my life and maybe a dozen or so 8 nights, so something between 6 and 7 is pretty fine.

We had a real crowd of people and I don't know how many times I heard the same comments about wanting to come to the Observatory all summer but being washed out. I can assure each and every one of you that the management echoes your dissatisfaction with the weather earlier this year! With such a crowd, many of whom stayed for a long while, we had a limited chance to change targets. So while we didn't hit that many target (about a dozen) we showed a lot of people a lot of the sky's beauty.

We started the night with Venus and Jupiter down in the remaining soupy clouds on the western horizon. Venus was spectacular - all sorts of colors which is actually a bad thing! Venus should be an almost perfect monotone white. The colors were all turbulence in the Earth's atmosphere. Jupiter was a little higher but it seemed to be plagued with a cloud deck that made it look like a pale blur. Jupiter's moons were frequently hidden. We figured that once these two planets had set, we'd be through with the planets for the night but we did not count on Mars. At first, Mars was as distorted as its fellow planets but as it climbed, it grew more stable and distinct. I am frankly at a loss to explain what both Joe and I saw. We saw the south polar cap where it ought to be, near the bottom of the nine tenths full Mars. Near the north of Mars we saw a dark band which would have been easily identified as Mare Sirenum EXCEPT that Mare Sirenum is a southern hemisphere feature. I checked my Mars maps and as far as I can tell there is nothing notable where we saw the band. I suspect it may have been Earthly turbulence but who knows. Perhaps we saw a dust storm on Mars.

We spent a good deal of time on three globular clusters M22 and M54 in Sagittarius, the magnificent Great Globular Cluster in Hercules (M13). M22 was fine; M13 when it finally cleared the dome was simply beautiful with innumerable crystal points of light. M54 can never compare to the other two on beauty alone, but the fact that this globular cluster was torn away from the small Sagittarius Galaxy which is colliding with the much larger Milky Way Galaxy by the MWG's tidal gravity makes it a spectacular subject. Strongly enough neither the Lagoon (M8) nor the Trifid (M20) were as fine as they usually are, even when we tried the O-III filters.

I spent a good deal of time outside leading four separate star sessions. The first was a standard rendering of the constellations. The second was a detailed pointing out of the Milky Way Galaxy, including whorls, arms and nodes. The third was a basic repeat of the first two sessions for later arrivals. The last one was something special, a tour with binoculars of several targets that few people realize are available to simple binoculars. M13 was easily picked up and several people could see some detail. However, the most stunning target was M31 - The Great Galaxy in Andromeda. Everyone seemed to be able to pick it up with binoculars, and almost everyone could see them by the naked eye. I have to admit that the green laser pointer is a wonderful tool for showing people how to jump from star to star to the galaxy. From Alpheratz (a star which is both Andromeda's head and the corner of the Wing of Pegasus) we marched down along Andromeda to the "waist band". We moved up from the "waist stars" to the "peg star" that holds Andromeda down and then we take a tiny skip to the right to the galaxy itself.

We finished off the night with M33 (Triangulum or the Pinwheel Galaxy) and finally with the Moon. The Moon was low and VERY unstable. I was struck by the appearance of craters "crawling" along the terminator. The crater rims were ringed with reddish and bluish tinges. I thought that it was mainly turbulence when Joe came in with a "clouds coming - over on the western horizon". Surely enough, the quality of the night dropped and moisture could be felt increasing almost immediately. We closed up, but it had been a fine night.

-Les Coleman

Leslie Coleman
Leslie Coleman
Entry Date:
Aug 26, 2005
Published Under:
Leslie Coleman's Log
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