Log, Dec 21, 2001

11 people. What looked like a very low quality viewing day turned into a very good - almost excellent - viewing night. The sky was literally cloudless and the transparency was exceptional. Even stiff competition with the Moon did not preclude examination of diffuse nebulae and low luminosity objects. Temperates started at 31 and dropped to 28. Winds were variable with gusts of at least 30 mph. I would rate the night at about 6 while the Moon was up and climbing to a 7 on our scale of 0 to 10 where 0 is totally overcast to 10 being as good as it possibly can get at FDO. The only thing that kept the average from being an 8 or better was the air was intermittently turbulent and constantly windy. Moments of great clarity and stability came and went. I could easily see the limb of the Moon without any wavering and Saturn's Cassini Division remained a sharp ring without blurring or gaps all evening long. For an hour and 45 minutes I had the 16" to myself which was a luxury indeed. I could spend as long as I wanted on each view. What added to the enjoyment was that the Dome behaved itself never stuttering or catching and the scope had a decent if not perfect alignment.

I had scheduled a class this evening but since we were as short handed as we could be and still be open [to wit me], I didn't set up the classroom. Around 8, Josh and Art came by, but they were more interested in viewing than hearing me drone on and on about my two scheduled topics "Rocket Sciece really ain't Rocket Science" [elements of orbital mechanics] and "Hypothetically Speaking..." [various speculations and topics in cosmology]. One other class member came by, but we missed each other because I was in the dome and the class member didn't come over. Oops. Oh well, we get far too few glorious viewing nights, a rainy Friday will come all too soon.

Saturn was a joy. Stable and we could spot seven moons, although we had to switch to a wider angle eyepiece to catch Titan, Hyperion and Iapetus. We made a joke of it. We decided that Saturn was too easy so we made individual target of the moons. Mimas was the favorite. We "ignored" the big ringed blob that was trying to block our view. Titan was a sharp disk when the turbulence was low and a definite dull tan/orange color.

I spent a good deal of time on Vesta [asteroid #4]. It was magnitude 6.9 (between the magnitudes of Uranus and Neptune) and showed what seemed to be a hint of a disk. I watched for brightness changes but couldn't make out any for sure.

I tried to determine if I could see the nebulosity around Maia (one of the Plieades - M45). This has always been a good check to see how really transparent the sky is. BY sweeping across the Plieades, I sometimes felt I could catch a glimpse, but it could well be "averted imagination".

Mars presented a distinct, if smallish, gibbous phase. Deimos was very easy to spot tonight although Phobos, close to the planet's limb, was not visible. I could see both the polar cap and Mare Sirenum (a large darkish area).

Jupiter was huge in the 12mm eyepiece. I watched an emergence of Io. What a pleasure to have the big scope all to yourself when a transient event occurs. Disks were clearly visible on all four Galilean moons which were arranged Io, Ganymede, Europa and Callisto as you moved away from Jupiter. I went back several times to the big guy as visitors came by. We watched the Red Spot move from the right center of the image until it turned out of view.

Yes, I looked at the Moon - or more correctly I watched HD221562 being occulted by a large bright light. The rills were very promeninent tonight with excellent shadow lines. One peak on the dark side was visible farther from the terminator than I can ever remember. It grew noticably dimmer from the beginning of the night to the end which I attribute to lengthening shadows. The dark side of the Moon was bathed in Earth light and craters were visable there if I moved the bright side out of the eyepiece. I looked long and hard at Mare Nectaris. I could see what appeared to be successive waves of "lava" which made multiple rills and scarps.

We went over to M42 several times as groups of people arrived [surprize]. While I was studying it myself, and more particularly M43, it was interesting to see the image clear to crystal clarity and then gains traces of color. I demonstrated this effect to visitors by using Sirius. Racked slightly out of focus, the star looked like a kalidescope. Winds were especially fierce the first time I was in Orion.

We made the tour of Messier objects. M1 was bright but not very distinct. I didn't try to use filters which would have enhanced the contrast. We went over to the lovely clusters M35, M36, M37 and M38. I love open clusters but some visitors are not impressed - just a bunch of stars. Josh Guarino was scanning the software when he came across IC405 whose name intrigued him - the Flaming Star Nebula. The Flaming Star which illuminates this nebula is a variable AE Auriga. I told Josh not to expect too much and unfortunately I was right. Josh felt the name was much to dramatic for the reality.

We spent some time looking at Beteleguese and Aldebaran. The topic had come up about red giants and the death of stars and these were obvious candidates. In case anyone has any doubt, they are still there, still whitish red and whitish orange.

Art wanted to look at M81 and M82 up in the north. We set the scope to turning and Les crossed his fingers as the cords wrapped around and tried to strangle the pier. All went well and these two galaxies were worth the efforts as they alawys are on a clear night. We also tried for several nearby smaller galaxies. In wide angle eyepieces both NGC3077 and NGC2976 appear with M81/M82 but we were using a 25mm eyepiece. Only one galaxy was visible at a time.

Josh wasn't the only one chasing Chimera with his Flaming Star Nebula. Les spent a rediculous amount of time looking for IC2574 [Coddington's Nebula]. Given the effort spent trying spot this object, and given my success rate [nill] it was awarded the faintly coveted "Smudge of the Week" Award.

We looked at M46 next. This is a toofer. M46 is a lovely open cluster which contains a planetary nebula NGC2438. These guys are worth tracking down with anyone who has a 8" or larger scope - maybe even a 6". Nearby is M41 whose most notable component is a very yellow star in a cluster of blue whites. NIce color contrasts. We went and looked at NGC2423 a very loose open cluster (almost a knot in the Milky Way rather than a cluster. We went over to M47 yet another open cluster which sports a prominent double star. I do not know if this double is a true double or merely a line of sight alignment. We swung to the nearby NGC2743. This is a small but nice cluster. We looked at NGC2252. This is a cluster which looks like a handful of tiny diamonds strewn across a dark background. It doesn't have the traditional central massing. We took a look at M79 which is yet another fine but small globular cluster.

The Rosette Nebula NGC2238 presented a challange. The problem with this object isn't that you can't find it but that it is so large that you fill the eyepiece with it. Seeing no edge, your eye quickly adjusts and it seems to disappear. The best way to see it is to pan back and forth across it. You eye adjusts and then you can see details. The wind was getting cold. Visitors had left (including one visitor from Halifax Nova Scotia}. Art and Josh were ready to call it a night. We finished with M44 [Praesepe or the Beehive] and NGC2392 which is called both the Clown and the Eskimo nebula.

-Les Coleman

Leslie Coleman
Leslie Coleman
Entry Date:
Dec 21, 2001
Published Under:
Leslie Coleman's Log
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