Log, Nov 5, 2004

12 people. Well if October won't let us view, maybe November will. The night started as mixed clouds and very windy but settled down to a much better than average night. By 10 PM the sky was largely cloudless and quite dry. The turbulent air made seeing less than perfect but we were able to split some fairly close doubles. It would help if I could get some time to collimate the telescope.

Jeff, a local high schooler with an interest in astronomy, was there first. We had arranged (via e-mail) for him to come and learn how to use the big scope and to do some viewing. Then we had to wait the better part of a month for a cle

Ernie had a list of planetary nebulae he wished to view through the 16". The wind made setting up outside very problematical. He suggested that we install the Oxygen-III [O-III] filter. I explained to Jeff that we used filters to increase contrast. The O-III filter allows the light of triply ionized oxygen to pass easily but blocks just about everything else. This means that they problem of "gray on gray" is much reduced. Ernie asked for NGC 7293 first. Now this is fine but I wasn't sure what this was until I realized it was my old friend the Helix nebula. The filter worked very well. The Helix is huge as far as planetaries go. We decided that we could see some annular structure. I explained to Jeff that "annular" meant "ring" to normal people. We went over to the Saturn Nebula NGC 7209 with the filter again. This nebula is supposed to look a lot like Saturn and its rings. Well maybe to some folk, but it has always been hard for me to see much similarity. We went on to the Blue Flash nebula NGC 6905. In this case we got a much better view without the O-III filter.

To give Jeff an idea what a more spectacular planetary nebula looked like we went over to the Dumbbell - M27 NGC 6853. It was very distinct. Since Albireo was so near we went over to it to see what it looked like tonight - excellent as almost always. Back to Ernie's list with the annular planetary nebula NGC 6894. It is quite faint but it was visible. We tried for NGC 6772 but this planetary was down near the horizon in the sky wash from the town of Westerly and the glare from Foxwood's Casino. We could not pick it out.

We went next to the Sculptor Galaxy NGC 253. The Sculptor, also known as the Silver Dollar Galaxy, is large and we looked at it in a series of eyepieces. Either the 25mm or the 40mm probably gave the best view. The 12mm cut off parts of the view. We could see some of the detail of the arms. We went to the nearby globular cluster NGC 288. This cluster isn't as bright as M15 or some of the other showpieces, but the stars in it are easily seen against the bulk of the cluster. I recommend it. We tried for a nearby double star HD4809. The 8th and 12th magnitude components are separated just about an arc second, barely more than a bulge.

We resurrected the faintly coveted Smudge of the Week Award recently. This week the award went to NGC 247 - a galaxy in Cetus not far from the bright star Deneb Kaitos. And a richly deserved award it was - the galaxy had everything that distinguishes a likely Smudge- boring, blah and low contrast. We followed this with NGC 246 which would have been a contender for Smudge except that this very low contrast (but reasonably large) planetary nebula surrounds a lovely loose open cluster of faint 10 and 11th magnitude stars. I strongly suspect that this loose cluster had a member which blew off the globes of gas that make up the planetary nebula itself.

One of the impacts of a solid month of rainouts is that the sky seems to make a leap forward when you finally get a good night. For quite some time I have been telling everyone that only the outer three planets would make an appearance tonight. Similarly, when someone would ask to see Orion or other winter constellations I would point below the horizon and say that the constellation wouldn't rise until the wee hours of the morning. And yet here was mighty Orion reclining on the south-eastern horizon. I couldn't wait to turn the scope on the Great Nebula. The Trapezium I am happy to affirm is still a brilliant small trapezoid, the great clouds still shine and M42 is as spectacular as ever. Ernie suggested we also take a peak at M1 - the Crab Nebula NGC 1952. I suspect that all of you know that it is the remains of a huge supernova in 1054. While I was in the neighborhood I turned to three stars in Orion which are multiple stars. If Epsilon Lyrae is the famed double double, these guys make up sort of a triple-double although they are merely an optical triple. They are all contained with NGC 1981 in Orion, an open cluster. They are HD37017 [Mag: 6.6 & 10.3 Sep: 0.4"]; HD37016 [Mag: 6.2 & 7.7 Sep: 0.4"] and HD37040 [Mag: 6.6 & 8.5 Sep: 4.0"]. HD37040 was easily split. HD37016 looked slightly elongated, and HD37017 looked like a single star. When Orion is higher, they should make an interesting test if we collimate the scope first.

By now Karl and Ernie had wrapped up in the yard, Jeff had gone home and I was alone with the scope. I turned it to the east and looked at Saturn with two of its moons Rhea and Titan easily visible. I decided to call it quits myself, satisfied that we had had a good if not spectacular evening.

-Les Coleman

Leslie Coleman
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Leslie Coleman
Entry Date:
Nov 5, 2004
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Leslie Coleman's Log
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