Observing Report - February 24/25, 2006

The Friday night/Saturday morning observing trip was excellent. I set off for this trip the most prepared I've been since I started doing this nocturnal activity. I'm going to say, right off the bat that all the extra cold-weather gear, especially the snowboard pants, snow boots, balaclava, chemical warmers and thermos of hot chocolate made it a much more comfortable experience. It got down to 18°F just before dawn, and there was no breeze at all...so it could have been worse, but I've still had sub-twenties chase me away before.

When I arrived at the observing site at Anderson Mesa, the sun had been down for about a half hour and it was a waning twilight that lit the gravel turnaround we use. Bill Ferris was already there, and almost finished setting up his 18" scope. I had my typical moment of indecision as I decided where to set up. As great as this site is for dark sky quality, it has several nearby ponderosas that need to be factored into the observing equation. I wanted to catch comet C/2005 E2 McNaught on the western horizon at dusk, and comet C/2006 A1 Pojmanski on the eastern horizon at dawn. I finally settled on a spot I thought would give me the best chance and started unloading all the goodies.

My first target, C/2005 E2 McNaught, turned out to be conveniently behind one of the trees I wanted to avoid. Further examination showed that viewing it would involve moving the scope out into the brush, or onto the entry road, and it just wasn't worth it. So I let it slip away.

So I spent time considering the large, dark nebulae between Taurus and Orion. I did some waffling about making a naked eye sketch, before turning my attention to Perseus and attempting to locate Barnard 5 telescopically. I could just detect some mottling and gaps in the faint Milky Way starlight, but it was hard to get a fix on the boundaries of that shadowy critter. So I tanked that one too. Hmmm, Oh-for-three. But I wasn't panicking yet. The night was still young.

I cruised over to the vicinity of M37 next. about 1.5 degrees west of M37 is another dark nebula, Barnard 34. This one was much easier to spot--for a dark nebula--which is to say, it was about as subtle as you can get. With dark nebula resting over an emission nebula, you at least have the opportunity to throw a nebula filter on the scope and bump up the contrast a bit more. Not so with the ones that sit over a starry backdrop. The initial impression I got of this nebula was a soft hole in the middle of the field. I was using my 32mm Plössl for a magnification of 37.5X and a width of 88'. I estimated the diameter of the nebula at about 1/3 of the diameter of the field stop--so about 30' across.

As I was getting a feel for the boundaries of this fuzzy shadow, Bill walked by to see what was up. He took a look and we discussed some of the features. Such as one of the stars that was nestled in the middle of the nebula. He also noted an impression of a fan-like structure sweeping away to the eastern side of the view. I hadn't picked up on that, so I took another long, extended look, and sure enough, there was some structure in the area. The tough part about sketching this object was laying down the star field. There were a lot of stars I wanted to plot, and it was a very slow process. The entire time, I wanted to jump into defining the boundaries of the nebula, but I had to stow my enthusiasm and get the stars right first. Finally when I got around to shading the Milky Way background, it got interesting. That's the most shading I've done on a DSO so far. My graphite pallet off to the side was a huge blur that lead right up to the sketching circle. I had to re-plot most of the stars afterward since they all got blurred within a hair of oblivion. When I get the sketch scanned, I'll post it and the observation in a separate entry.

Around this time, Dave Saunders showed up and started setting up his super-tall 18" scope. ...Eighteen inches to the left of me...Eighteen inches to the right...etc. etc. =)

My next stop was NGC 2244, the Rosette Nebula. While it is faint, it is a real beauty. A large open center populated by the brighter stars in the clustner, surrounded by roughly circular petals of nebulosity. This was another sketch where I had to pace myself on the star plotting and not try to hurry through to get to the nebulosity. Look for a post and sketch on this one soon.

At this point, I took some time to test out some diopter flippers for naked-eye observing. I'm going to make a separate post about this, but I have to say these things made an amazing difference. Bill was also pleasantly surprised after taking a look through them. After seeing what a -.75 diopter difference did for my night vision, I'm going to be ordering a pair of stargazing glasses asap!

Bill had pulled up a view of M100 with Supernova 2006X making an appearance. It was an easy catch in his scope. I wanted to give it a shot in my 6" reflector, so I moved to that next. After a little trouble starhopping to the right spot, I finally got a view of M100. There wasn't any obvious spiral structure, but it was circular, with a strong core. There was a brighter edge along the northwest edge that was suggestive of a spiral arm, and brightening in the inner regions that seemed to stretch northwest to southeast.

Locating the supernova was every bit as difficult as I figured it would be. A pinprick of light occasionally flickered in the right location, but at one point, I had 3-4 seconds of steadier flickering that made me feel pretty good about spotting it. Theoretically, the limiting magnitude of my scope is 13.38. But it seems like I'm seeing fainter than that. After checking my sketch against an AAVSO chart of the area, I noted that two of the stars I saw fairly easily were marked as mag. 14.2 (see the two stars in the linked chart that are right against the edge of the galaxy and marked 142). I'm assuming those are blue magnitudes, and that their visual magnitudes are more like 13.5 or 13.4. The thing is, they weren't that hard to spot, so I know I can see fainter. I think I'm misunderstanding something here. Anyway, I'll be posting this observation soon as well.

About 1 AM, Bill packed up and headed home "so I can fall asleep in my bed instead of Lake Mary Road," he said =) After that, I grabbed a sketch of M109, and then took a look at a shadow transit of Io across Jupiter. Io had a nicely saturated orange color to it. Dave offered me a look at the tidally stretched tail and knots of galaxies NGC 4676A and B (the Mice), and then a look at planetary nebula NGC 3242. He had the magnification cranked to 375 X, I think, and what a fantastic sight it was. He said he likes to call it the CBS Eye, and that's a great description. Outside its main boundaries, I was also able to see some faint filamentary threads stringing away from its blueish core. What an amazing sight.

Dave finally packed up and left around 4 AM. I settled down for a naked eye sketch of the rising Ophiuchus Milky Way and Scorpius with the Pipe Nebula featuring prominently. I did this one as white pencil on black paper...well, let me put it this way: white pencils and yellow pencils look the same under a red light. So it was a yellow Milky Way when I looked at it under the light of day. Those diopter flippers really came in handy, by the way. This was a very enjoyable sketching experience, and something I want to do more of. Like I keep saying, I'll post the scanned sketch soonishly.

I took a moment to look for the dark nebula Barnard 86 in Sagittarius and found it easily next to an open cluster. There wasn't time for a sketch though. I'll have to save that for later.

As the eastern edge of Sagittarius finally lifted over the trees, I prepared to look for comet C/2006 A1 Pojmanski. As I walked around the observing area, I realized I was going to have to move the scope to catch it before dawn got to bright. I'm really glad I stayed out all night to catch it, because it was a beauty. As soon as the right area cleared the trees, it was immediately visible through the low power view of the scope. Its coma was bright, and very nicely condensed at the core. Averted vision presented a tail blowing off to the southwest. In addition to the bright, thin core of the tail, there also appeared to be a broader, fainter tail overlapping it, and about the same width as the coma. It took magnification nicely, and at 240X, I could see some asymmetry in the coma. The pseudo-nucleus was not stellar at this magnification though, which could have something to do with poor seeing near the horizon. It showed up easily in 10x50 binoculars as a soft stellar object, and was just barely visible to the naked eye with approaching dawn beginning to interfere. Sketches to come!

And that was it. I packed everything up, started the car, and finished my notes inside with the toasty heater running. It was a fantastic observing night, and something I hope to do again as soon as I catch up on the lost sleep.

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About this Entry

This page contains a single entry by Jeremy Perez published on February 24, 2006 6:00 PM.

Planning a Major Observing Night was the previous entry in this blog.

Barnard 34 is the next entry in this blog.

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