Sunday, September 26, 2010
The Herschel Project Night 12
Why ain’t there no score up there? You know, like, “390 Objects Down, 10 to go”? Because I didn’t stay on the beaten path of the Herschel Project this past weekend. As y’all know, the focus of The Project, at least as far as its presence in this blog goes, has been the Herschel II list. I am very close to the end there, with only a few objects remaining. So why didn’t I pursue some of those this past Saturday evening? I couldn’t.
Saturday afternoon’s weather was, at best, “mixed,” with periods of occasional clearing being interspersed with times of plenty of clouds. The sky was rancid enough that I didn’t bother to start marshalling my gear in Chaos Manor South’s front parlor till close to four o’clock, when it began to look as if I might get some time under the stars after all.
My mind made up to go for it, the question was “with what?” I ruled out the Stellacam right away. I didn’t feel like dragging out a lot of astro-junk for what looked to be a cotton picking skunk festival. Also, I’ve recently come to believe I need to emphasize the visual side of the Herschel project a wee bit more than I have thus far.
Which scope? The C8 without doubt. The 8-inch Schmidt Cassegrain is still king when it comes to a perfect balance of aperture and portability. What would my Ultima C8 OTA, Celeste, ride on? If I’d had good sense, I would have grabbed the CG5, but I promised y’all I’d give EQMOD a go on the Herschel Project, and decided this would be as good time as any to do that—that’s what I thought, anyhow.
Arriving at our club dark site in Tanner-Williams, Alabama, about an hour’s drive from the Old Manse, I was immediately dismayed. It was hot. It was humid. It was cloudy, particularly to the west, never a good sign. There was one good thing, however; the mosquitoes didn’t seem as hungry as they were earlier in the summer. I fired up the Thermacell, anyway, but I wasn’t bitten once while I waited for it to heat up and start doing its thing. I also noted that, while plenty of clouds hung ominously in the west, we seemed to be getting a few sucker holes across the rest of the sky. Might as well get set up.
As I said not long back, the Atlas is big and it is heavy, but in truth is not much more of a pain to set up than the CG5. Once you get the EQ head on the tripod (which is almost identical to that of the CG5), it’s no more of a pain at all. Bolt it on to the tripod, leaving that bolt a mite loose until polar alignment is done to facilitate azimuth movement, plug in the power cable and the SynScan hand control or EQMOD cable, and you are done except for attaching the OTA and rigging the dew heaters (which I’d obviously need in a bad way this humid night).
Since I wanted to give EQMOD a spin, I eschewed the HC and plugged a standard serial cable into the mount, hooked the little EQDIR module to the other end, and plugged that into the Keyspan USB – serial adapter I use with my ASUS netbook. The Keyspan has made all the difference in the world both with EQMOD and with NexRemote. A run-of-the-mill USB-serial gadget from BestBuy will usually work if all you want to do is send a mount on go-tos with a planetarium program, but get fancy, as with NR or EQMOD, and most of these fall flat on their faces. Just can’t handle the increased message traffic these very special programs require, I reckon.
Speaking of netbooks, my little Asus has done more to make my setup easier than anything has in a long time. It’s small, maybe half the size and a third or fourth the weight of my good, old, Toshiba Satellite (which has recently gone to the Happy Hunting Grounds, sad to tell), but its screen is still more than large enough to be legible. Yeah, I have to wear my reading glasses, but lately I have to wear them no matter what the size of the monitor. The Asus’ max screen resolution, 1024x768, is more than sufficient to accommodate any astro-program I’ve got in my inventory. Storage? At 250 GB, its hard disk is three times the size of the pore old Satellite’s drive.
Better than any of the above, though, is the little PC’s power-sipping nature. Miss Dorothy encouraged me to get a netbook with the best battery I could find, I did, and that has proven to be a godsend. My Asus has an advertised battery life of 11 hours, and, while I don’t know if it really will make that, it sure does run for a long time, even with lots of serial port/usb activity. It easily lasts as long as your tired old Uncle does. Which means my days of toting an enormous deep cycle marine battery and an inverter just for the ‘puter are over, muchachos.
Yeah, I plugged up EQMOD, but as darkness came on, more clouds flowed in, and I decided there hadn’t been much reason to. The west looked a little better than it had earlier, but now the entire eastern side of the Local Meridian was completely covered. One of the major benefits of EQMOD is that it kicks the Atlas’ go-to accuracy up a notch over what is available with the SynScan hand controller. Really taking advantage of that, however, requires aligning on six stars or so on each side of the Meridian. With only the west now clear (barely), I wouldn’t be able to do that.
I was hot, a little tired, and put out at the weather. I decided I didn’t feel like messing with EQMOD, and unplugged the serial cable, replacing it with the SynScan HC. Which turned out to be a mistake. Oh, it needn’t have been. The SynScan HC actually worked rather well on its last outing. But I was, again, tired and in a snit and took the easy way out.
After I’d polar-aligned the Atlas, which is easy with it polar scope, one of the best in the business in my opinion, at least as regards the quality of its optics and the AFOV of its eyepiece, it was time to do a go-to alignment. The only two viable options with the SynScan are “two-star” and “three-star.” I chose three-star, since it usually—but not always—results in a slightly more precise alignment.
If I’d done what I did last time out, all would have been well. But I didn’t. Instead of carefully scrolling through the alignment stars the SynScan offers and picking the best choices, I just accepted whatever it came up with on its own. It is critical the first two alignment stars in a three-star alignment be as far apart as possible, especially to include being several hours apart in R.A., and most of the time the first two stars offered by the HC do not satisfy that requirement. In my defense, there were enough clouds that I probably couldn’t have done much better with alignment choices than the SynScan did.
After some fiddling around, I got an “alignment success” message, and sent the mount off to M13 as a test. The Great Globular was not centered, but it was well within the field of the 13mm Ethos eyepiece at f/6.3 via my Celestron reducer/corrector. Not bad, I thought. And it wasn’t bad, not at first.
Alignment done, on-deck was the question of what I was gonna target on this increasingly poor evening. The remaining few Herschel IIs were out. The single one still above the horizon, a wee galaxy in Virgo I missed this past spring, was just about to set and in a cloud bank, anyway. And this sure didn’t look like a night for running through the Big Enchilada’s, the Herschel 2500’s, dim deep sky objects. So, what?
The original Herschel 400 list’s DSOs are, naturally a part of the 2500, and while I’ve been through the HIs a time or three, I want to reobserve everything for the Herschel Project. Also, I am guessing you might enjoy reading about my observations of ‘em more than you would the about the non-Herschel I/II fuzzies of the Big Enchilada (“small, faint 14th magnitude elliptical”). There are some real gems in the first 400, including some spectacular Messiers. So, now that the HII is about done, I am gonna take you-all through the original H400, I reckon.
I started out with a couple of Hercules aitches, since I was in the area already, and, them done, I walked over and took a gander at SkyTools 3 running on the netbook. Looking at the H 400 list and the current condition of the sky, it ‘peared Ophiuchus would be a good place to begin. The Snake Handler was getting on toward the west, but not outrageously so, and had the big plus of being relatively free of the worst of the clouds. I punched up the first of his H400s and was soon rocking with my beloved Ethoses.
That didn’t last, alas. After I’d worked my way through the OPH fuzzies that weren’t too low or obscured, I switched over to neighboring Sagittarius. Before starting Chiron’s Herschel Is, though, I thought I’d take a quick peek at one of my all-time faves, that great big granpappy of a globular star cluster, M22. When the SynScan HC beeped, indicating the slew was done, I put my eye to the 13E and saw…NOTHING. A couple of other experimental targets in the area were also out by fair amounts. That simply would not do.
What would I do? If I’d a-had good sense, I woulda realigned the SynScan on better alignment stars or fired up EQMOD. Amazingly enough, the sky was beginning to clear off by this time, with the Milky Way beginning to, if not burn, at least glow prominently, and there were plenty of good alignment targets horizon-to-horizon. Unfortunately, I again chose the easy way out. I used the SynScan’s sync function, which is called “PAE,” “Pointing Accuracy Enhancement,” when I entered areas where my go-to accuracy began to fall off.
That mostly worked OK (though it sometimes seemed as if I needed to sync on a couple of stars/objects in a given area before my go-to accuracy improved). In retrospect, it would have been easier just to realign the SynScan or go with EQMOD, but my syncing worked. I didn’t miss a single target due to go-to inaccuracy, though the PAE business was something of a pain.
Lesson learned? If the sky ain’t what it oughta be or I’m tired or distracted, the CG5 is a better choice. The alignments offered by the current Celestron firmware are deadly accurate, with “bad” star choices and poor polar alignment not doing pea turkey to lessen accuracy. Yes, the Atlas is worlds better for long exposure imaging, but the CG5 is more than good enough for either visual or Stallacam work. You know what? If my CG5 ever bites the dust (knock on wood), I will go right out and buy anudder one. This little mount has become my astronomical security blanket, and, like Linus, this kid his keeping his trusty blanket at his side from now on.
I suppose it sounds as if Night 12 of the Herschel Project was a bust, but it really wasn’t. Yes, the weather was a pain in the rear at first, and I could have managed the Atlas better, no doubt about that, but in the couple of hours we had before the sky closed down for good, I managed to bag over twenty Herschel Is in three constellations. Not a record by any means, but not bad for a below-average summer’s eve. I promise I’ll resume ticking the fuzzies off with more alacrity and regularity now that the sky (I hope) is getting clearer and calmer as October comes in.
First up was NGC 6229 (H.IV.50), a magnitude 9.4, 4.5’ diameter globular cluster in Herc (yes, there’s a third globular star cluster in Hercules). With C8 and 13mm Ethos (97x), it is very prominent. Round, unresolved. Forms a triangle with two magnitude 8 field stars about 6’ to the west. Granular in appearance as if it wants to resolve.
NGC 6207 (H.II.701) is the little galaxy 28’ northeast of M13. Easy enough with direct vision in the 13 Ethos, but averted vision shows a little more of this 3’ across intermediate inclination SAc spiral. A soft glow that’s obviously elongated.
It’s a Messier, but not much of a Messier. M107 (H.VI.40) is OK in the 8mm Ethos (157x), but given its somewhat lackluster nature and the fact that it is near the horizon, this loose, Shapley-Sawyer class X (10) globular would have been easy to pass over if I weren’t paying attention. Some resolution, with a few of its teeny-weeny stars winking in and out.
NGC 6287 (H.II.195) is a large globular star cluster, nearly 5’ across, shining serenely at magnitude 9.3. Unfortunately, it is currently low on to the horizon, and most of the time looks like nothing more than a round smudge. Easy in the 13mm eyepiece, however. A few cluster stars are seen, popping off like fireworks, with averted vision.
Yet another glob, NGC 6401 (H.I.44), is also very low in the sky. A round cosmic dust bunny without any resolution or graininess apparent. A magnitude 9.3 field star is 8’ to the south. In truth, this globular looks a lot like an undistinguished planetary nebula on this night in the C8 with the 8 Ethos.
NGC 6284 (H.VI.11), still another Ophiuchus globular cluster, is quite decent. This magnitude 8.9, 6.2’ object shows off a condensed core. A pair of mag 9 field stars lies about 10’ to the west. No evident resolution or graininess in the 13mm Ethos.
NGC 6355 (H.I.46), a magnitude 8.6 globular, is just barely visible in the 8mm eyepiece. It is no more than 10 degrees above the horizon, and given the haze and humidity, I am surprised I can see it at all.
The next globular, NGC 6293 (H.VI.12), is very good tonight. It’s big, 8.2’ in diameter, shining bravely at magnitude 8.3. Shows graininess and even some resolution around its periphery. Most resolved stars are picked up with averted vision.
Low down in the sky, Ophiuchus glob NGC 6316 (H.I.45) is a ghostly glow in the 13mm eyepiece, a round smudge a few minutes in size. There’s a magnitude 8.5 field star 19’ northwest of the cluster.
NGC 6304 (H.I.147) is also almost into the trees, but this magnitude 8.3 globular cluster shows up very well in the 13E. I don’t see any resolved stars, but I do see a fairly bright globe of light with a tight-appearing core.
NGC 6818 (H.IV.51), the Little Gem, is a very pretty planetary nebula. A round, tiny (22”), and strongly-colored blue ball. Thanks to its small size, it is very bright at magnitude 10. 13 Ethos shows it well.
NGC 6440 (H.I.150) is a small but attractive globular star cluster. I don’t see many—if any—hints of resolution in this 4.4’ mag 9.3 fuzzy, but it is attractive nevertheless, positioned along a line of four magnitude 11 – 12 stars.
Planetary nebula NGC 6445 (H.II.586), “The Box” is fairly large, 35”, and fairly dim, magnitude 13, but it’s easy enough to see in the 8mm, though all that’s visible is a round smudge with no sign of the object’s weird, rectangular shape . A prominent double star is 5’ to the east.
NGC 6629 (H.II.204) is an OK small (16”) planetary nebula. An OIII filter helps a little, but there is really not much to see in the 8E other than a tiny disk near a magnitude 9.5 field star. This nebula is, if nothing else, set in a lovely, rich field.
A small but beautiful globular star cluster, NGC 6642 (H.II.205), is also set in a very rich star field. Best in the 8mm eyepiece, where it looks grainy and almost resolved. I seem to catch sight of a few tiny stars occasionally with averted vision.
NGC 6544 (H.II.197) is very nice. This glob is not overwhelmingly bright at magnitude 7.5 given its large 9.2’ size, but it is in a pretty field of dim stars. Fair resolution with the 8E.
NGC 6638 (H.I.51) is a small globular with a small core that’s very prominent in its field. I am not sure I detect a bit of resolution in this 9.2 magnitude cluster, though.
NGC 6553 (H.IV.12) is nice in the 8mm. This Sagittarius glob is easy to see despite its near 10’ size thanks to a magnitude of 8.3. A mag 7.7 star is 12.5 minutes to the south. Some graininess and maybe an occasional cluster star seen with averted vision. It’s mostly a globe of mist in the eyepiece.
Globular cluster NGC 6522 (H.I.49) is near the horizon and is somewhat loose with a Shapley – Sawyer class of VI. In the 13E, I do see some cluster stars. The 8mm eyepiece doesn’t improve the view much, if at all.
NGC 6624 (H.I.50) is also very low now. Large at 8.8’ and bright at magnitude 7.6, I suppose this globular would be very attractive when higher in the sky. Easy to see in the 13mm, though I don’t note much resolution. Prominent, condensed core.
The Digital Sky at Night
If you read “Digital Issues,” you’ll recall I praised the UK’s Sky at Night Magazine for continuing to do a great job with its “cover CD,” but I also said I sure hoped they, like Sky and Telescope, would soon offer an honest-to-god online edition of the magazine itself. Wasn’t but a day or two later that I got an email from Graham Southorn, who, as you may know, is the magazine’s talented editor. He said Sky at Night was on course to go digital, and that he’d see I got a subscription once all was in place.
That happened just the other week, while I was up in DC for Miss D’s daughter’s, Miss Beth’s, wedding. I spent a fair amount of time sitting in the hotel room while Miss D and Miss B and the other women in the wedding did girl stuff, so I was absolutely delighted to get an email saying my digital Sky at Night subscription was ready to go. I hustled right over to the website of Zinio to have a look see (SAN, like S&T, has a third party doing their online digizine version).
What I found was very similar to Nxtbooks’ Sky and Telescope. And that is a good thing. Oh, there are a few things missing from the Zinio e-reader that I hoped to see, like the ability to save issues as.pdf Adobe Acrobat files, but mostly I was impressed. Looks good, works good.
If nothing else, this will be a boon for English speaking amateurs who live outside the UK. With the digital version, we are no longer nearly a month behind Old Blighty, which is where we are with print issues of Sky at Night Magazine. Expect a full review/rundown on the digital SAN “soon.”
Guess what, y'all? I have just received one of Hotech's new "Advanced CT" SCT laser collimators for evaluation. I've just barely got started with it, but if all goes well you'll get a full report on it either next Sunday or the Sunday after. First blush? I am very impressed with the gadget's build quality; it's just plain luverly!