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Sunday, March 17, 2013

Déjà vu all Over Again...


That was the way it was last Tuesday, and that was both good and bad, muchachos. The good was that I was able to get a look at and some pictures of our little visitor, Comet Panstarrs, C/2011 L4. More good was that I was able to do that from the Possum Swamp Astronomical Society’s dark site on a freaking Tuesday evening. This retirement thing really is cool. Oh, I’ve stayed out late for various astronomical events on work nights over the years, but when you are facing a 4:30 a.m. wakeup, some of the fun just drains out of whatever it is you’re up for. NO more of that.

But, yes, there was bad, too. If you’ve been in the astro-game for four decades or more, you must remember the notorious Comet Kahoutek and her COSMIC WATERGATE. I went into some detail about the whole stinking affair here, but if you don’t want to bop over and read that right now, I can sum it up pretty quickly.

C/1973 E1 was not a terrible comet. She was better than most of those I’d seen in the wake of Comet Ikeya Seki in 1965, but Kahoutek wasn’t much, no avoiding that. Maybe magnitude 2 or a little better when I saw her. That wasn’t a problem for me, but it was a problem for a lot of non-astronomers, and is what the “Cosmic Watergate” business is about.

At first, Kahoutek, who was discovered when she was way out in the distant reaches of the Solar System, looked good. The media, aided and abetted by professional and amateur astronomers, were soon touting the comet with as much hyperbole as they could muster. We were, in fact, being told by ABC/NBC/CBS and more local weather goobers than you could shake a stick at that Kahoutek, which would be at its best in December of 1973 and January of 1974, would provide an incredible holiday fireworks show.

Was the public excited? Were they ever! Everybody from the Peanuts gang to Sun Ra got in on the act. As is not uncommon when a great comet is on its way in, there was also a dark side; some folks, mostly a brace of crazy preachermen, decided this comet must in fact mark the End Times. The end of the world, that is.

The denouement was instructive but not nearly as exciting as The End. Astronomers, amateur and pro, had assumed too much, and you know what they say about that word. First of all, it had been assumed Kahoutek was a virgin comet on its first trip into the inner Solar System. Secondly, it was assumed that would make for a superior show. Thirdly, it was assumed the comet would stay in one piece.

Not one of those things turned out to be as expected. This was probably not Kahoutek’s first trip around the Sun. But even if it had been, we are now aware that a comet’s initial pass usually makes for a worse display. After surface volatiles boil off early on, the stuff below, hard frozen as it is, just sputters. Worst of all, as Kahoutek neared the Sun she began to break to pieces.  When it was showtime, most of the public didn’t see a trace of her. The comet was fairly bright, but low to the horizon in all the mess down there.

I was happy enough with the comet, but the same thing couldn’t be said for Joe and Jane Sixpack and, especially, for the network news goobs. The public, who didn’t have much idea what a comet should look like anyway, didn’t see what they had been led expect: a blazing orb plowing through the winter skies. They were understandably right put out.

The newsmen and newswomen? They were freaking outraged. The scientists and NASA had LIED to them. Made them look like fools. The end result was that till we got close to Halley-time nary a peep about comets did you hear from the media. Even spectacular—and it really was—Comet West was ignored by them a couple of years later, and for that reason few people outside the astronomy community saw what I believe was the comet of the century.

“The more things change, the more they remain the same” and I am convinced that if there’d been a little more lead time on Panstarrs it would have been Cosmic Watergate II.  Lucklily, though, there wasn’t enough time for the TV networks and the websites to get people all stirred up. Still, that didn’t stop some folks, including those at a prominent astronomy magazine who should have known better, from overstating the “spectacle” inherent in this little comet. I am proud to report that Sky and Telescope, on the other hand, had been sounding a cautionary note for weeks.

Anyhoo, good, bad, or indifferent Unk is always up for viewing a hairy star, especially one that might reach naked eye visibility, if only barely. So, on Tuesday evening 12 March I loaded up the 4Runner, Miss Van Pelt, in minimalist fashion and headed to the club dark site.

What did I lug out? Not much not compared to what I have with me for a Mallincam run. There was my time-honored Canon 400D DSLR and its 18-55mm zoom for imaging, our Manfrotto tripod to mount it on, and my netbook computer to run the Canon with Nebulosity. Yes, I could just have exposed for 30-seconds per frame using the camera by itself, but not having the netbook screen for focusing is a sure path to blurry images for me. It’s also a lot easier to tell Neb to take ten 30-second images than it is to fool with the shutter release and self-timer.

Looked as if it would be a fairly nice night at first:  cool but not cold, cloud-free, and dry for a change. Since it did appear to be a superior evening, I couldn’t resist also loading the C8 and CG5 for a little piggyback imaging or maybe some visual gazing once the comet was done.

‘Course I needed to have at least a rough idea where the comet would be. To do that, I fired up TheSky 6. I don’t use that planetarium program for everything, but when I’m looking for comets I almost always do. It is easy to download new orbital elements and get your quarry onscreen in a hurry. Yep, there was Panstarrs in the west not far from a young Moon and low in the sky, a mere 10-degrees above the horizon just after Sunset. What I should have done then was print out the chart. I didn’t:  “Shoot, I can remember where the little sucker is.” Ha!

The hour-long trip to the PSAS dark site was not too bad. I should have taken rush-hour into account and allowed myself more time, but I was used to Saturday afternoon traffic and didn’t. Still, not so bad. What appeared might be bad, howsomeever, was the band of clouds to the south I began seeing as I neared Tanner-Williams. “Consarned weather goobers. Do they ever get it right?” Reckon not. They had been predicting dead clear, and there was most assuredly some mess coming in off the Gulf. Oh, well, what would be would be.

It was after 6:30 before me and Miss Van P. rolled onto the field, so I did have to scurry a little. Sunset would be at 7 p.m. or thereabouts, and the comet, who was reported to have a magnitude between 1 and 2 (positive), would be available shortly thereafter. Got the tripod set up, camera on that, USB cable to laptop, shutter control cable rigged (older Canons require a shutter interface for long exposures). When I was done, I grabbed my 15x70 binoculars and started scanning the western horizon for the comet.

Also scanning was an old buddy, Max, who, in addition to his camera, had brought out a sweet 80mm ED refractor on a GEM and a 5-inch Celestron NexStar Newtonian. We weren’t alone; we had a few non-astronomer visitors eager to see the comet. I hoped we’d be able to show it to them, but it got darker and darker and no matter how much I looked with my beloved Burgess 15x70 binocs, no Panstarrs did I see.

I was beginning to lose hope when Max spoke up, “Rod the comet is supposed to be above the Moon.” I fired back:  “NO, MAX! It’s below it!” Till I had thought for a minute and a few of my remaining brain cells fired. Max was exactly right. TheSky had shown Panstarrs slightly above and south of Luna.

My head on straight, finally, and the sky a little darker, it wasn’t long before I bagged the comet. What I saw in the Burgesses was a tiny triangle of golden light not far from beautiful, slim Luna. I could easily make out a brilliant star-like head. Panstarrs looked a lot like Hubble’s Variable Nebula looks in an 8-inch scope at medium power. Without binocs, the comet was completely invisible. It would get darker yet, so I thought we might get a glimpse of it without optical aid eventually, though. I tossed the binoculars to our guests and headed for the camera.

Normally, getting Nebulosity going is easy. I was a little concerned about that on this night since this would be my first time under the stars with the latest version of the program, Nebulosity 3. Just in case, Neb 2 was still on the hard drive. Turned on the camera, launched Nebulosity 3, pulled down the camera selector and picked “Canon Digic II/III/4.” And immediately got a warning message:  “It doesn’t appear you have a Canon camera connected.” Rut-roh.

I shut down the camera, closed Nebulosity, and fired back up with Nebulosity 2, which worked fine. For the heck of it, I shut down 2, ran 3 again, and dismissed the error message. Guess what? Nebulosity 3 worked fine. I’m thinking I may need to upgrade to a more recent version of 3. I’ve posted about my problem on the Stark Labs Yahoogroup and hope to get an answer from one of the gurus there soon.

Alarums and excursions over, I began shooting the comet. First thing I had to decide on was exposure. 30-seconds sounded about right. I could have put the camera on the piggyback mount on the C8 instead of the camera tripod and gone longer, but there wasn’t any reason to do that. It was bright enough in the west that more than 30-seconds would be overexposed, and would probably still be overexposed until the comet was almost gone. At 30-seconds of exposure and 55mm of focal length (equivalent to 80mm or so with 35mm film), any trailing would be completely unnoticeable.

I focused up with Nebulosity’s Frame and Focus function: mashed the “go” button, and the program started the camera taking short (1 second) exposures. It was easy to focus on the distant tree line at infinity—I’ve learned through bitter experience never to trust the infinity marks on a camera lens.

When the picture displayed on the Netbook screen was as sharp as I could get it, I proceeded to set up the first sequence. At about 15-minutes after sundown, it was still a little bright, so I went for five exposures of 30-seconds each. Pushed the “Capture Series” button on Nebulosity to get things underway, and wandered over to Max’s little Celestron Newtonian while the computer and camera did their thing.

Before looking through the Celestron I did some staring at the horizon. Every once in a while, as the seeing changed or haze/smoke passed, I reckoned, I could see Panstarrs naked eye. Only occasionally  was it visible as anything more than the merest smudge, and from our location it was a marginal naked eye object at best.

In the telescope, the comet was surprisingly good, if not great. At 50X, it was still small, but showed off the intense golden “star” of its head and its small triangle of a tail well. What came to mind as a description? “Mini Hale-Bopp.” To my eye, the comet’s broad triangular tail had the same foreshortened look to it the Boppster displayed. Comet scoped out, I got out of the way so Max could shoot some pictures through his reflector.

Just as I gave up the eyepiece of the Celestron, Nebulosity emitted the fanfare sound that means “exposure’s done.” A look at the last frame showed it was now dark enough to get serious. I modified the settings from “5 frames” to “10 frames” per sequence, keeping the exposure at 30-seconds. I changed the focal length of the zoom from 18 to 55mm and back on each succeeding set of subframes. Even at 55mm, it was easy to include the photogenic earth-lit Moon in the pictures.

And so it went for the next half hour or so, till little Panstarrs sank to the point where she was a big zero with both binoculars and cameras. Max and I did a little fiddling around with our telescopes for a while after that, but not for a long while. I think both of us were eager to get home and see how our comet pictures had turned out. In this modern digital age, unlike in the film days, you pretty much know if you got something, but, still, you don’t know exactly what you got until the pictures are stacked and processed.

I had the best intentions of going right home and processing my pictures digital-darkroom style. Alas, by the time I’d packed up my modest amount of astro-junk, motored home to The Old Manse, and unpacked, it was getting on toward 10 p.m., time to open the Rebel Yell locker, not crank up pea-picking Adobe Photoshop.

After sufficient coffee the next morning, I set to work. Not that there was much work to do with my simple wide field shots. Stack with Nebulosity—whose stacking routine works better than anything else I have ever used—tweak curves and background color with Neb’s processing tools, do a final touch-up with Photoshop, and I was done.

Verdict? I was pleased with the images you see here. In retrospect, I could have used a little more focal length to bring out Panstarrs better…but…Max was shooting with more millimeters and so were other PSAS folks from other sites, so I was happy to be the wide-field guy.

Posted some of the pix on Facebook Wednesday, did a little movie about the comet with Microsoft Moviemaker (I’d shot some video and terrestrial stills with my Fujifilm camera while Nebulosity was doing its thing), and sat back. So much for Panstarrs, I thought. Till late that afternoon when Miss Dorothy asked if I were going out to the site again. I hemmed and hawed till Miss D. indicated she was a little surprised I’d let a beautifully clear sky with a comet in it pass me by.

Naturally, that got me to thinking. Why not head to the PSAS field again? No worrying about the shipyard the next morning, after all. But what would I do out there and how would I do it? I could piggyback the 66mm William Optics ED refractor on the C8 and get those longer focal length images, I reckoned. But that just didn’t appeal. What did appeal was allowing the little visitor to strut whatever stuff she had, to show exactly what she could do visually. The 4.5-inch StarBlast, Yoda, with his wide field would be excellent for that. But my 100mm binoculars would be a tad better.

The inexpensive Zhumell 25x100s, which I reported on in this entry, are a handful, no doubt about that, and the Pete Peterson EZ Binocular Mount Miss Dorothy and I built for them is an even bigger handful, but no pain, no gain. I also felt a little guilty that I hadn’t used the Zhumells, which have excellent optics, a little more often. They had not been out of their case in six months.

Alrighty then. Wasn’t much trouble to snatch up the Zhumells in their nice case and toss ‘em in the back of the truck. The mount was different. Getting it downstairs and into Miss Van Pelt was akin to wrestling with that vaunted octopus. I removed the four counterweights and the three pipe pedestal legs and it still wasn’t a treat, but I got ‘er done.

What else did I take with me? That was about it. I did grab my leather flight jacket and a ballcap since it would be both clearer and colder this evening. I thought about brewing up a thermos of coffee, but didn’t believe I’d be onsite long enough to drink much. I planned to be out of there and out of the cold not long after Panstarrs set. I did print out a TheSky chart showing the comet’s position: fool me once, yadda, yadda, yadda.

Back on the field, job one was getting the binoc-mount set up. More octopus wrestling to get it out of the vehicle and plenty of head-scratching as I pondered the subject “Which pipe goes where?” Lucky for your silly old Uncle, I still had pictures of the assembled mount on my iPhone. I’d shot those before the Chiefland expedition linked above, and they allowed me to get the mount figured-out and the binoculars on it in ten minutes or so.

The only trouble I had with the Zhumells was the same trouble I have with any binoculars, especially high power binoculars and binoviewers. My eyes invariably have trouble merging images. For a while, anyway. After I get focus set and interpupillary spacing correct, and my brain, such as it is, gets accustomed to binoculars again, the images merge easily. By the time it was dark that was just what happened with Panstarrs—who’d I’d run down as soon as possible with the aid of the chart and the Zhumells’ red dot finder (a 25X anything must have a finder of some kind, y’all).

How was she? Sure did make the struggle with the binocular mount worthwhile. I had little doubt the big glasses were getting everything out of the little comet that she was capable of giving. In addition to the striking, bright yellow head, the small fan of a tail began to give up detail: hints of streamers and even a “shadow” effect along the tail’s northern edge. I was as pleased with Panstarrs as I had been with Kahoutek on that chilly long ago night when I hunted her up from my backyard in the university student housing ghetto.

After the comet sank? How about Jupiter? He was nice in the Zhumells. 25X is enough to show a little cloud-banding. What was truly remarkable? That the humble pipe mount allowed me to view The King at all, since he was nearly at the zenith. After that it was, natch, the sword of Orion. What was uber cool was how the big binocs showed many of the same details in the nebula you’ll get in a telescope, but also showed all the star-laden fields up and down the sword in the same view.

I could have gone on for quite a while with the Zhumells, but it was getting cold and windy. OK, OK, fess-up time: it was also getting spooky. The owners of the airstrip where we do our observing had thoughtfully turned off the runway lights (the field is closed at night) and the hangar lights, and it was dark indeed. My PSAS buddy James, who was the only other person to make it out Wednesday night, had had to leave a while before to get to his job, and it was getting lonelier and darker by the minute.

Shortly thereafter, I heard a twig break, which sounded like a rifle shot in the silence. It was, I knew, nothing more than a possum or a raccoon. B-U-T. As my mind will do in these circumstances, it soon transmuted Mr. Possum into The Skunk Ape. Or maybe it was Mothman who was skulking around. That was all I needed. The Zhumells and mount went into the truck just as fast as I could get them broken down.

Back in the warm and comforting confines of Chaos Manor South I sat watching a DVD of Horror of Dracula with my black cat buddy, Thomas Aquinas, and ruminating on the latest in my long string of comets. I sure hope Ison comes through, because I feel a little bad about what I have heard from the non-astronomers friends who’d been so excited about Panstarrs, “They said we could see it right after dark, but we didn’t see a thing.”

As always, I urge restraint concerning the potential of the next comet. With so long till its passage, there is more than enough time for a Cosmic Watergate II to develop. Hell, even if we urge caution, a poor showing will still give astronomy a black eye. Fair? Nope. But sometimes life just ain’t fair, and it is almost always not fair in the comet game, muchachos. Occasionally we do get lucky, of course. Think “Hale-Bopp” and “Hyakatuke.” As always, cockeyed optimist Unk will be wishing and hoping, déjà vu or no déjà vu.

If you’d like to see more pictures from my Panstarrs expeditions, I have an album of them posted over on Facebook. Not a Facebook friend of Unk? All you gots to do is ask…

Next Time:  Astrophotography the Old Fashioned Way…

5 comments:

  1. Thanks for another great article. You're stuff is both real-world helpful and enjoyable. Could there be a book on Astrophotography for the Rest of Us on your to-do list?
    Pete

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  2. Thanks. Well, I've certainly thought about that. At the moment I am working on a book on the Herschel Project...but after that...who knows?

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  3. Rod, I forgot to congratulate you last week on your retirement! I hope you are able to spend a good portion of this extra time under the stars. Please keep up the writing! There are a great number of us who look forward to your weekly blogs. Always inflormative and insightful.

    Bill. ( still under several feet of snow in WI)

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  4. Just stumbled across your blog trying to find star parties here in South Mississippi. Love, love, love your stories!

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  5. There's no longer a star party in south Mississippi, but it's not far away. The Deep South Regional Star Gaze, which will be at the end of October this year, is held just over the state line near Clinton/Norwood, Mississippi. ;-)

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