Sunday, July 17, 2011

 

Unk’s Messier Album 2


As you can probably tell from my latest Herschel Project report, Unk likes serious observing. But not all the time. Sometimes I want to look at the sky in a slightly more relaxed fashion. Still, I’m not normally an informal observer. It’s been my experience over the years that unless you have a project going or at least a list of objects to look at, you wind up seeing very little: “Well, done seen M13 and M57…guess I’ll look at The Lagoon and call it a night. Cain’t think of much else.”

Unk’s informal, but not too informal, observing project is his Messier Album. What I am doing is going through those famous deep sky objects as laid out in the wonderful series of late-sixties – early-seventies columns in Sky and Telescope, John Mallas and Evered Kreimer’s “A Messier Album” (which later became a book, The Messier Album), and seeing how what I see in my telescope compares to what legendary observer Mallas saw in his. If you want more details on the Album Project, go here, but that’s really all there is to it.

John Mallas’ telescope, as I mentioned in the first installment of this series, was a 4-inch f/15 Unitron Photo Equatorial achromatic refractor. Alas, Unk does not have such a beast, though he sure wishes he did sometimes. I do have something roughly similar as far as the images it delivers, though, my 5-inch ETX-125PE, Charity Hope Valentine. So, when Unk wants to observe at the old dark site, but bugs and clouds and laziness vote against taking on The Herschel Project, Unk and Charity hit old Chuck’s wonders with the aid of Mallas and Kreimer.

And that’s the way it was the Saturday before Miss Dorothy and I were to set out on our latest Chiefland adventure. Part of me wanted to manhandle the C11, Big Bertha, out to the Possum Swamp A.S. dark site and give her a shakedown before the Florida trip, but a look at the thermometer, which was still stuck in the mid 90s a couple of hours before sunset, and a look at the skies, which were resolutely hazy, changed my mind. Oh, CHARITY!

I figured at least attempting another Messier Album installment would be relaxing fun if nothing else. So I loaded up the car with the bare minimum of gear I would need to do that: Charity and her tripod, a 12-volt jumpstart battery, our observing/camp table, a notebook with a printed list of the Mallas/Kreimer Album objects arranged as they originally appeared in Sky and Telescope, my tackle-cum-accessory box, and my little case of humble 1.25-inch eyepieces—mostly Orion’s (Synta’s) 66-degreee AFOV Expanses. If I needed a chart, there was SkySafari on my iPod or the print Sky and Telescope’s Pocket Sky Atlas. Oh, and the Thermacell to keep the bugs away, natch.

Arriving on-site, the first thing I did was get the Thermacell cranking. Even though it’s been relatively dry, there are still plenty of skeeters, and the Thermacell, which works by heating a pad imbued with allethrin repellent from chrysanthemum flowers with a small butane cartridge, will keep ‘em off, no ifs ands or buts. The beauty of it is that you don’t have to slather yourself with icky plastic-eating DEET repellents that might do who-know-what to your bod. The only bug-bites I got on this evening were when I stepped out of the 4 - 5-meter protective bubble of the Thermacell to help out a buddy.

It was hot, muchachos, if not too humid-sticky, and I was sure glad I didn’t have a ton of astro-junk to set up. With the table erected and the eyepiece case and accessory box on it, all that was left to do was put Charity on her tripod and we would be ready to roll. I didn’t even bring dew heater strips and the DewBuster. It looked like the night would be reasonably dry, and Charity’s corrector plate doesn’t dew up easily, anyway. If I did get the damp corrector blues after a while, I had one of the little 12-volt hairdryers/window defrosters we all used to use for dew-zapping.

The sky? Hard to tell. It looked OK, if hazy, at sundown and the few clouds to the west appeared to be moving off. I was suspicious, however, because the horizon was ringed with clouds. It looked as if the only clear spot anywhere was a giant sucker-hole right over our heads. Would it last? I hoped so, but if not, the ETX and everything else could be back in the car in less than ten minutes and I’d be headed to the cool and dry comfort of Chaos Manor South.

With the bright stars winking on, it was time to get Miss C. go-to aligned, which is always an adventure. Since she is the PE model ETX, all I had to do to put her in her initial “home” starting position was undo the azimuth lock and rotate her counterclockwise until she stopped at her “hard stop.” That done, you lock her back down, power up, and begin alignment.

Despite me not having leveled Charity, she came satisfyingly close (for her) to her two alignment stars. By the way, don’t waste a lot of time leveling your go-to rig; it won’t help accuracy a bit. All it will do is ensure the initial alignment stars are a wee bit closer to the center of the finder than they’d otherwise have been. Anyhoo, I centered up Charity’s choices—Vega and Spica, I recall—and she responded with “Align Success.” Uh-huh. Unk knows your ways, Missy. Let’s see you center M3.

Rut-roh. The big Messier glob was not in the center of the field of the 20mm Expanse. It wasn’t anywhere in the field. It wasn’t even close. With Charity, that signals one thing: time to train the altitude and azimuth drives. I’d noted this behavior coming on last time I’d had my Maksutov girlfriend out, and I should just have done Drive Training, which allows the scopes’ computer to take backlash into account, as soon as I’d set the ETX up tonight. It was now too dark to use a terrestrial target, which is the best way to do the procedure, so I did the training on Polaris, me centering the star, Charity slewing away, and me re-centering it to complete the training.

Did both axes, hit the big switch, and re-did the go-to alignment. I’m not sure if that is necessary, but I did it anyway. When I issued the go-to command to M3 again, the cluster wound up in the field, if not precisely centered after Charity Hope Valentine stopped her huffing and puffing. Takeaway? As I’ve learned, you simply have to do Drive Training every once in a while.

Don’t want to fool with the Drive Training? You can enable the ETX’s Precise Go-to feature. In that mode, the telescope first points at a bright star near the target, you center it, and the scope then proceeds on to the final destination, which will almost invariably be in the eyepiece field. Problem is, it is time consuming if you want to cover a lot of ground, and while the Autostar chooses “bright” stars, most of ‘em are kind of off the beaten path, and you may need a chart to identify them. All in all, occasional Drive Training is easier.

Charity settled down, it was time to get to work. I initially thought we’d go through the galaxies in Leo, but a look at M105 disabused me of that notion. There was heavy haze to the west, and while M105 was visible, it was surprisingly dim. Since the goal of The Album Project is to see how close I come to what master observer John Mallas saw, there wouldn’t be much point to hunting galaxies in compromised skies.

What then? This would be a night for globs, globular star clusters. Scorpius was out of the light dome (barely), Serpens was in the clear, Ophiuchus was getting there, and the sky was now looking pretty good to the southeast. That would give me and my gal a more than sufficient selection of objects to work. As I said in the first installment, I want to take this slow. Mallas and Kreimer usually only did two or three Messiers each column, and I don’t want to exceed that by much. I want to see how much I can wring out of each object with my (relatively) small scope.

As before, the plan was simple: I’d spend plenty of time with each Messier and then complete a preliminary (rough) drawing. My exact sketching procedure? I take my drawing pad, an 11 by 9-inch spiral-bound sketch “diary” to the eyepiece with me and draw-in field stars with a Sharpie marker (I’ll have prepared generous-sized eyepiece field “circles” beforehand). Mallas tended to leave out most/all stars not associated with the objects. Not me. I find they help me more accurately place the details of the target DSO. Why didn’t Mallas draw field stars? Since he tended not to sketch open clusters at all, I assume he just didn’t like drawing stars.

What about the DSO itself? It depends somewhat on the individual Messier and its type, but generally I leave the sketch diary on the nearby observing table, walking back and forth. I’ll look till I’m sure about some facet of the thing, walk over and put that in the drawing and repeat as needed. I don’t smudge nebulae or try to draw any but the most prominent stars in a globular. I make notes and outlines. I will sketch peculiar details carefully—like M13’s Propeller or M8’s Hourglass. I generally use an hb hardness drawing pencil for all this.

That is just the beginning. The next morning—no later, I don’t want to forget how the object looked—I do a finished drawing using a variety of hard and soft drawing pencils, blending stumps, gum erasers, and the other tools you will find at your local art supply store—one of the best “astronomy accessory” dealers around.

The final stage is scanning the finished drawing into the computer, where I will complete it with Paint Shop Pro or Adobe Photoshop. Depending on what the sketch needs, I may use many of the programs’ various tools. One thing I always do is replace my drawn stars with good looking ones I produce with the imaging program’s airbrush tool, taking care to keep them the sizes I originally sketched. Finally, I’ll invert the color to “negative” so I have nice white stars on a black background.

If you are serious about sketching, the above is just the beginning. There’s a lot you can do to refine your pictures in the computer—you might even use a little color in stars. My sketches are certainly not world-class (for some of those, see the Cloudy Nights sketching forum), but they look good to me and record what I saw, which is my goal.

So, here we go. The matter in italics is transcribed from my log, and, as before, if this is to be the most fun for you, you need to go and get a copy of the Mallas Kreimer book or load up the Sky and Telescope DVDs. Whether you have the Mallas book or columns or not, I commend to you a wonderful online reference to the Messier, the SEDS Messier Database. In addition to descriptions and pictures, it includes the vital stats for each wonder.

M4 and M80 (June 1969)

Mr. Mallas and I saw and recorded about the same things in M4, the Cat’s Eye Cluster. John says that in his Unitron “The cluster is a well defined circular glow with a brighter center.” Further, he notes that at 214x this class IX (loose) globular star cluster begins to break up around the edges. Yeah, I saw about the same thing, though I was able to see all those little stars at lower power, and my drawing shows quite a few more stars outside the cluster’s curious central “bar” than Mallas saw.

M4 is very beautiful and nicely resolved with the 20mm Expanse (94x). I also see four brighter stars in a kite-shaped asterism 5’30” to the south-southwest of the glob’s center. The “iris” of the Cat’s Eye is composed of many dimmer stars in a very prominent line. Surrounding it are more of these tiny sparklers—a horde of them.

M80 is a tight little Shapley – Sawyer Class II (highly compressed) glob, and it was a little difficult for me to pick out many cluster stars. John beat me on this one; his drawing, which I presume was done at high magnification, though he doesn’t say, shows many stars all across the cluster’s face that I didn’t detect.

M80. The other Scorpius M globular cluster is surprisingly large tonight. There is a bright magnitude 8.47 field star 4’15” to the northeast of the cluster’s center. It is not easy to resolve this tight glob, but I do see occasional little stars wink in and out in its halo. Bright and very tight core. Dims smoothly to its edge.

M5 and M9 (June 1970)

John Mallas was every bit as impressed with M5, a Class V globular, as I was, calling it “One of the finest globular clusters in the heavens…” But that’s about all we have in common on this one. He notes chains of stars like “spider legs” that I didn’t see, and for him the core is triangular, while I saw it as distinctly square. Furthermore, I saw quite a few more stars at 125x than he did at what, judging from his drawing, was a higher magnification (again, he doesn’t tell us how high).

Despite the barely passable transparency, M5, the great globular in Serpens, is a marvel. The bright, grainy center is surrounded by a large number of tiny, tiny stars. Absolutely breathtaking with the 15mm Expanse (125x). The core seems almost off-center, and at times seems to have a square shape. A bright star, magnitude 5.06 5 Serpentis, is only 22’ to the southeast.

As with M5, John Mallas and I saw distinctly different versions of Ophiuchus’ Class VIII M9. His drawing of this globular looks a lot like a lenticular galaxy surrounded by a little haze. My sketch, in contrast, shows a normal looking cluster just beginning to resolve.

M9 is still a little low on the horizon and just barely out of the worst of the light dome. Nevertheless, as I look it transforms from a round smudge to a partially resolved cluster, with lots of little stars popping on and off around its periphery like fireworks. Set in a rich field. Best-looking in the 15mm Expanse, though the higher power of the 9mm (208x) does bring out more stars.

M6 (July 1969)

I meant to look at M7, not M6, since M7, not M6, is a part of the June 1970 group, but I got befuddled as the night grew old (so what else is new?) and did 6 instead. But M6 is nicer than M7, anyway, and who says I can’t jump around? While Mallas comments that M6 is “One of the finest sights in the heavens,” he doesn’t really say much about it other than that it looks nice and “(It) shows very little bunching of stars in the middle.” While I didn’t get the Butterfly shape, I was taken by that very bunching Mallas missed.

Mallas didn’t draw the Butterfly (open) Cluster, M6, so neither will I. This is a beautiful collection of bright stars, but is really too large for a telescope of this focal length. It’s hopeless to try to see a butterfly here, even with the 40mm ProOptic Plössl (47x), but the cluster is still striking and rich with lovely a cross-shaped asterism of stars at its heart. One of these nights I will turn my 25x100 binoculars on it.

Supernova in M51. Since M51’s new supernova, SN2011dh, was at its height, I thought I’d see if Charity would show it up. While conditions had improved markedly over the course of the evening—as midnight approached, the Milky Way was pretty bright as its arch reached for the zenith—they were still not perfect. Given the way it looked in a nearby 15-inch Dobsonian, I wasn’t sure I would see the Type II (the precursor was a single, giant star) at all. A little staring, and eyepiece switching, though, and there it was. It wasn’t easy, but it wasn’t that hard, either, standing out fairly prominently in one of the galaxy’s outer arms. I estimated it to be a little dimmer than magnitude 12, and I suspect it would have been a lot easier if not for the fracking haze.

I didn’t stop there. I’d completed the “official” Messiers of the evening, but it will still not quite midnight, so I toured around a bit, paying most of my attention to the Sagittarius – Scorpius area. Big old fat-daddy-spider M22 near filled my field with tiny stars stretching out from his oval body, and, over in Scorpius, the little Bug Nebula tried to scamper away, but was not able to escape Charity’s gaze.

As the clock struck 12, I noted the sky had begun to degrade again. The humidity had also spiked up, with me having to dew-zap the corrector every 10-minutes or so now. All in all, it seemed a pretty good time to throw the Big Switch. Once again I was reminded of the best part of a Charity Hope Valentine night. Man-oh-man, how nice it was to have the junk back in the vee-hickle in a few minutes and be enjoying the Toyota’s AC (it was still in the 80s at midnight) and headed for the Rebel Yell bottle.

Next Time: Another Year Older…

Comments:
Dear Uncle Rod,

Let me summarize what you already mentioned: M5, a class V globular, is near the mag. 5 star 5 Serpentis. To this I may add (I was doing this area two weeks ago, too), that the said star is also the starting point for star-hopping to the nice distant globular Palomar 5. Which was discovered in 1955. A silly coincidence, but it makes these numbers hard to forget.

Yours,
Ivan Maly
 
That is a cool coincidence I never thought of before. Thanks!
 
Rod:

That's just the way I use my C5 on the SLT mount. Everything but the legs in a Celestron Box for SLT mounts I got about 15 years ago when a science store closed and the trunks were $15 a piece. I keep my C8 in the other one I got.

I upgrade the HC to the NSX software and took the little beast to a dark site 3 day starparty. I was pretty amazed what you can see in a 5" scope at a dark site. 7331 showed great extension, and I was able to resolve globular clusters a lot better than from the house (white zone).

It is sometimes a great relief to have a small light setup that is both goto and 5" of aperature.

Nice report.
 
Very nice sketches! Thanks for the tips on sketching and of setting up an ETX, both will help my own observing sessions!
 
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