Saturday, December 24, 2011
A Chaos Manor South Christmas: 2011
It’s Christmas Eve, muchachos, and Unk feels like telling a Christmas story. Something I’ve done a couple of times before, like here. The story this Christmas Eve? The events surrounding Stephanie’s telescope didn’t occur at Christmas, they happened just after, but the tale has the feel of Christmas, and I feel like telling it, so we’ll call it a Christmas story.
When did Uncle Rod’s magnificent obsession with the Great Out There begin? I don’t know. Honestly, y’all, I can’t remember a time when I wasn’t thinking about OUTER SPACE. Certainly by the early 60s, when I’d got my hands on a cheap pair of toy binoculars and a planisphere, the idea of astronomy, practical astronomy, not just what I read in books, had taken root in me. Not that I knew what to do with that idea.
Stephanie’s Telescope showed me what to do, but that little A.C. Gilbert was actually the second part of a one-two punch that pushed me over the edge into a lifetime of wonder. The first part came the night of First Spaceship on Venus. If you’ve read my blog article about it, you know First Spaceship, along with The Angry Red Planet and Journey to the Seventh Planet, is a member of the triumvirate of Sci-Fi (not SF) films that have remained in this old boy’s pantheon for fifty years. It isn’t really Spaceship that is important here, howsomeever; it’s what happened after the movie.
Like I said in the blog entry, First Spaceship had its initial U.S. release in 1962, but it did not show up down here till a year or two later, when it was shown at the Roxy, Possum Swamp’s cheap-seats theatre. They played first-run films, too, but not first-run films like Lawrence of Arabia. More like Tammy and the Bachelor and one of Mama’s other faves, Horrors of the Black Museum. And they showed lots of second run (or third or fourth run) flicks starring Abbot and Costello and the Bowery Boys. And lots of sci-fi like First Spaceship on Venus.
I won’t say too much about that remarkable film from the exotic Soviet Bloc other than that, yeah, it was remarkable. In many ways it was ahead of its time, even years after it was filmed, and in the pre-2001: a Space Odyssey and pre-Star Trek days it was far stranger and more compelling than even the best American efforts like Forbidden Planet. All on what must have been a laughably miniscule budget. If’n you want to know more about the film and more about li’l Rod’s reaction to it, read its dadgum blog entry. Suffice to say that when the credits rolled Mama had a hard time prying me out of my seat.
Mama, in her usual slightly disorganized fashion, had got us to the theatre about ten-minutes after the movie started. I was so taken with it that I wanted to watch at least those first ten minutes—if not the whole movie—when they ran the film again. Back in those gentler times you were allowed, maybe even encouraged, to do that. You filled a seat, and you might visit the concession stand again. I know I would have begged Mama for a refresh of my supplies—ten-cent box of popcorn, Orange Crush, Almond Joy—if she’d agreed to watch First Spaceship again.
Normally, convincing Mama to sit through a movie twice wasn’t a problem. She preferred to stay at the Roxy till as close as possible to the time Daddy would arrive back home after sign-off at the TV station where he worked. As I have often said, Mama was in many ways a strong woman, but not when it came to enduring the hours of darkness alone in a house with a little kid. She would not assent this time, though, “We have got to get home, young man. Have you forgotten already? This is the night The Den is going out to look through the big telescope. I thought you were the one who was so interested in space?”
As y’all know if you’ve read this blog often, I loved Cub Scouting, and what made me love it was mostly my Den Mother, a very special—if somewhat peculiar and spinsterish—person, Miss Emily Baldwin. Mizz Baldwin had the not young – not old appearance some middle-aged southern women assumed back then. She seemed utterly changeless year upon year. What also never changed was her commitment to us kids.
Not only did she serve as a Den Mother and as an MYF Youth Leader at our Methodist Church, she was a substitute science teacher at the Junior High School, and later went on to teach—or really preach—the wonders of science fulltime to a couple of generations of kids. I suppose I was very lucky to come to Miss Emily’s attention. She made my life interesting, if not always pleasant. Like Mama, she always had the idea I might be UP TO SOMETHING, and she was not shy about getting on the phone and communicating her suspicions. As I’ve said before, if only she and Mama had realized how timid li’l Rod really was.
Whatever. What mattered was that Miss Baldwin’s prime mission as a Cub Scout leader was to get her charges, and, I suspected, particularly me, Interested in Science. To that end, she was always arranging activities, contests, and field trips with a scientific slant to them. On this fall evening, she’d outdone herself. She’d arranged the mother of all field trips. She had set up a visit to Spring Hill College’s observatory.
Spring Hill College, then and now, is Possum Swamp’s kinda sleepy, kinda small, very pretty Jesuit College. As is sometimes the case with small, backwater institutions, they had an outstanding astronomy program due to the presence of a charismatic professor whose passion was the stars. As is also often the case, this program did not long outlast this person’s tenure. But for a while there was some pretty serious astronomy going on up at the ‘Hill. To the point where a domed observatory holding, Miss Emily told us Cubs, a gigantic telescope was built in a corner of Spring Hill’s golf course.
I don’t remember the drive out to the college, packed in the backseat of one of the moms’ cars with three or four other Cubs, but I sure do remember what I saw when we got there: a perfect little observatory dome. I say “little” now, but back then it looked enormous. Big enough to house Mount Palomar’s Hale Reflector, which I often obsessed about. I had read a somewhat tacky science fiction novel about Palomar Observatory, The Big Eye, seven or eight times, and that great instrument had become my totem, my touchstone, my religious icon. I know one thing: Miss Emily sure didn’t have to shoo me inside.
Spring Hill's scope, a 12-inch Cave reflector, was not what we'd call "big" these days, but when I entered the small dome I felt as if I were standing in the company of and dwarfed by the mighty Hale. I didn't mind waiting in line for a little while, either, since I could gawk at the indecipherable star charts (probably Becvar’s Skalnate Pleso atlas) and funny-looking clocks that were revealed in dim red light.
Above all, I could admire The Telescope with its lustrous, nearly glowing white tube and massive equatorial mount. No, 12-inches doesn’t sound like much today, but even now a 12-inch long focal length Newtonian on a large German equatorial is a big telescope. When it was my turn to ascend the ladder to the Cave's eyepiece, I felt as if I were climbing all the way to the Hale’s prime focus cage. Then it came: my first look through any scope.
Memories can deceive, but what's locked in my mind near fifty years later is a perfect vision of M51’s glowing spiral arms. That may even be accurate, since a 12-inch Newtonian would have been perfectly capable of revealing considerable spiral detail in the bright Whirlpool Galaxy in those not-so-light-polluted days, even for the newest of novices. It was all I could do to keep from tumbling off the ladder. My mind reeled, and then got a grip, a tiny grip, on the true scale and majesty of the Universe.
I didn’t begin to come back down to Earth till we all stopped at Possum Swamp’s brand new (and first) Macdonald’s. I munched those crazy fries and 10-cent hamburgers with the rest of the Den, getting ketchup all over our uniforms and the Moms’ cars in the process—no indoor dining at Mickey D’s in them days—but even then part of me was still far, far away, out among the galaxies.
I daydreamed—and dreamed—about The Telescope for weeks and months, but being just a little chirper in a big, wide world, I didn't imagine I could have a telescope of my own. I went back to my semi-toy binoculars and my star finder (planisphere) and the outer space shows on TV like my fave, Fireball XL-5. No, I had no idea I could have a scope. Until one after-Christmas show-and-tell day in the 4th grade.
Is show-and-tell still done in elementary schools? I don’t know, but it was very popular in the antique days of the early sixties, giving us and our teachers a break from our normal routine of studying the multiplication tables between duck and cover air-raid drills with Bert the Turtle. Show-and-tell went like this: you brought an item to school (a toy, a book, even a pet) and stood up in front of the class and gave a short talk about it. 47 long years later, I have no idea what I brought on that winter Friday morning, but I remember with laser clarity what my classmate Stephanie brought.
Stephanie usually had good stuff, being from the upper middle class rather than the middle-middle (really lower-middle) class like me and my buddies Wayne Lee and Miss Jitter Jones, but what she brought on this day was beyond good. Perched on a spindly metal tripod was a long black tube. Almost instinctively, I knew it was a telescope, a telescope for looking at the stars—not a dime-store spyglass like I used when me and Wayne Lee and Jitter were playing pirates.
I knew it was a telescope, but I couldn't figure out how you looked into it. The "eye thing" seemed to be on the wrong end. Stephanie soon explained all: this was a special sort of a telescope, a reflecting telescope, which used a mirror instead of a lens. She went on to tell us that she and her Daddy had used her Gilbert (I had one of their cheap microscopes) to see craters on the Moon. Imagine that: they could look at Moon craters. Any time they wanted. Stephanie let us all have a peep through the classroom windows at a distant telephone pole, and that was that. Which was enough for me. I had to have a telescope. HAD to.
Over the next few months, I made a lot of noise to Mama and Daddy (a.k.a. “The Old Man” or “The Chief Op” around our house) about wanting a scope, and I believe they allowed as how they'd "see about it" (usually code for "No, you'll forget about it soon enough; we can't afford it anyway."). No telescope was forthcoming. Perhaps they wanted to be sure I was serious in my odd new preoccupation, or maybe the money really wasn't there. It's easy to forget it amidst the nostalgia for those supposedly more innocent times, but in the late 1950s and early 1960s the lower middle class had resources more akin to those of po’ folks today. But I didn't stop pestering, and I think Mama eventually realized how serious I was and communicated that to Daddy. Eventually there was a big and ragged and almost unmanageable 6-inch loaner scope, which was followed not long after by a telescope of my own.
One morning, just as I was waking up to get ready for school, Daddy came through the door to my room with a telescope in his arms. I barely heard what he said, a simple “I happened to go by Joe’s Loan last night during my supper break and saw this and thought you might like it.” That was plenty. I didn’t care that the little Tasco came from a pawnshop. It looked new and may have been. Daddy’s pal Joe sold a few new things in addition to his huge assortment of used, “hocked,” stuff. Used or new, it was love at first sight.
The new telescope, my new telescope, was a thing of wonder. Gleaming white metal tube, beautiful wooden tripod, and a couple of shiny lenses (what I called eyepieces initially). Most of all, this 3-inch Tasco Newtonian seemed to be straining in her traces, eager to gallop into the sky like a thoroughbred. You can bet that school day was a long one. All I could think about was my scope. I even tried the “Miss Stinson, I feel SICK! Can I go home?” ploy. Strict Miss Stinson applied a no-nonsense hand to my forehead and told me to HUSH, sit down, and get out my math book. Yeah, it was gonna be a long Friday…
When evening finally came, I turned the Tasco to the sky, taking first light on a nice, gibbous Moon. From that moment on my course was set, even though the Tasco did not turn out to be quite the thoroughbred I thought she was. Her optics were not-so-hotsky, doing OK on the Moon, OK on the few deep sky objects I could find, and poorly on the planets. I was not dismayed. Instead, I began drooling over the Edmund Scientific catalog Daddy gave me and, just like all us gear-mad amateurs today, dreaming of More Better Gooder that could take me farther.
I don’t have many mementoes from those days. For the longest time, all I had was a single snapshot of me posed with my wonderful telescope, my dog-eared copy of Stars, and a Moon picture or two I took with the Tasco and my Argus box camera. Then, not long ago, I took custody of the mount from Spring Hill’s old Cave reflector. The second I laid eyes on the time-worn GEM head, I was pretty sure where it had come from. Nevertheless, I was gobsmacked when further investigation revealed this relic was indeed part of that wonderful telescope from so many, many long years ago.
What will I do with the mount? It still works—even the drive runs—though it could use considerable restoration. That will come, and I will put a suitable instrument on it. Maybe a big achromatic refractor. For now, I just pat it every once in a while in passing. When I do, memories from fifty long years ago come flooding back, memories of Mama and Daddy, and the Tasco, and Miss Emily Baldwin, and long-ago Christmases, and, particularly, of Stephanie’s telescope.
|The mount from THE telescope.|
Tonight, Christmas Eve...
After a late lunch in celebration of stepdaughter Beth's birthday (at the Olive Garden as per usual), younger daughter Lizbeth joined us for the traditional annual showing of A Charlie Brown Christmas (via DVD). Unk settled in to watch, savoring a wee nip of the Yell, of course, and ruminating on the Christmas of 1965, the year Charlie Brown premiered. I tried to settle in, anyhow
I was on EDGE, muchachos. Christmas Eve night had assumed the character of a race. As you know if you've been reading this here blog for a while, me and Miss D's other Christmas Eve tradition these many years has been to grab a scope and hie ourselves into the yard for a look at that greatest of all Christmas ornaments, M42. The 3-inch Skywatcher refractor, Midge, was near the front door and ready to go, but would we see anything? A front of heavy storms bringing thick clouds was approaching from the west as fast as ol' Orion was rising in the east...
For the second time in two years, Unk was victorious. All five us us, me, D., Beth, Beth's husband Rob, and Lizbeth, trouped out into the front yard and, despite low altitude and haze and light pollution, the great nebula shone through. Did it ever. We drank in the ancient photons and one and all proclaimed it a good omen. Soon, your old Unk will be off to bed, visions of Mallincam Xtremes dancing in his head. I hope you all have a wonderful Christmas, a Christmas just as numinous as ours is turning out to be.
Next time: Happy New Year 2012 from Chaos Manor South!
Sunday, December 18, 2011
You Gotta Guide
Yep, if you want to take astrophotos, long exposure deep sky astrophotos, you have to keep a “guide” star centered for the duration of the shot to make up for telescope misalignments and mechanical gear errors in your mount. Well, that’s not strictly true, muchachos. If you have an uber expensive mount or are willing to settle for multiple 30-second – 1-minute subframe exposures at relatively short focal lengths you stack into a final image, you can get by without guiding.
But that is not most of us. Most of us are using mid-level mounts, in the EQ-6 to G11 range. And most of us are of the opinion that our results will be better, our finished pictures more noise-free, if we expose each subframe longer. We will still stack multiple exposures into a finished image, but the longer we can go on each subframe, the better.
If you’ve been in the astrophotography game longer than about fifteen years, I don’t have to remind you what a pain guiding used to be. Back in the not-so-good old days of film astrophotography, we guided manually. What that meant was you stared at a dim star in a crosshair reticle eyepiece for long periods, often through a devilish little device called an “off axis guider,” an “OAG”
An off-axis guider was attached to the focuser or visual back ahead of your camera and had a small prism or mirror that intercepted light from the edge of the field and diverted it to the guiding eyepiece. The prism was small enough and close enough to the field-edge that its presence wasn’t noticeable in finished images, even in a 35mm frame. 'Course, being small and being at the field edge meant it was limited in the number of stars it could see. With an SCT, stars at the hairy edge of the field were misshapen too—often looking more like commas or seagulls than pinpoints. Locating a star bright enough and round enough to use for guiding was a challenge—to put it mildly.
Why didn’t we use guide scopes, separate small refractors (usually), to guide? Some of us tried, but over our long film exposures--half an hour or more--the chance of flexure was high with our long focal length guide scopes (their magnification had to be high to allow you to see any small “excursions” the star would make). If the guide scope flexed, moved independently of the imaging scope the tiniest bit, stars would be trailed in the final image no matter how carefully you guided. Then as now, no astrophotographer liked non-round stars, so most of us resigned ourselves to OAG hell.
Once there was a guide star sitting in the crosshairs of the guiding eyepiece, the fun had just begun. You stared at that star for the length of the exposure. If it moved off the crosshairs even a little, you pushed the appropriate button on the hand paddle, the hand controller, to bring it back.
|One of Unk's manually guided 35mm film shots.|
The coming of the CCD camera changed everything. The most important thing it did was shorten the length of most folks’ exposures. With sensitive CCD cameras, or even today’s ubiquitous DSLRs, many imagers, including Unk, start hitting the skyfog limit, the point where sky brightness due to light pollution becomes a problem, in two or three minutes. Three minutes is a lot easier to deal with for manual guiding than thirty, but by the time the CCD revolution was a few years old, we found we didn’t have to—guide manually, that is.
The autoguider revolution started with something called the “ST-4,” the first camera produced by the legendary SBIG, Santa Barbara Instrument Group. While the ST-4 could take pictures, its small chip made it mostly of interest as an auto guider for folks doing film imaging. We were skeptical that this (expensive) little widget connected to a box with a few LEDs on it could guide a telescope accurately, but it could—in the right hands. The settings, guide star, and mount all had to be just right, but the ST-4 most assuredly could work.
As the 90s came to an end, the ST-4’s guiding system, which issued relay-closure signals to the mount to guide, just like you were pushing the hand paddle buttons yourself, became the default standard. Mount makers left and right added “ST-4 compatible” autoguide ports to their mounts, and many CCD camera makers furnished ST-4 guide outputs on their cameras.
The ST-4 was there first, but almost any CCD camera could be used to guide a mount, a modern go-to mount, at least. You just needed the right software running on a PC. For a while, the standard was SBIG’s CCDops, the simple program that came with Santa Barbara’s cameras, and which most of us learned on. Then came CCDsoft from Software Bisque, which was definitely a step up, at least as far as features. Finally, there was Maxim DL, which was and is for some folks the king of guiding (and imaging and processing).
For those of us not stationed under desert skies with plenty of time to pursue pretty pictures, and those of us not after serious scientific results, Maxim DL was overkill, however, at 600 bucks. What if we just wanted to guide our mounts? Didn’t need lots of frills, and didn’t want to spend that much money?
A cool little (freeware) program called GuideDog was popular for a while. Not only was it free, it worked. Alas, it had some rough edges and was designed to use modified webcams for guiding rather than standard CCD cameras or guide cameras. Its author stopped developing it by about 2004, too. I kept looking, and eventually heard about PHD, “Push Here Dummy,” Guiding from Stark Labs. Amazingly, that was just what PHD Guiding was. You pushed a button (well, actually a couple of buttons), and it calibrated itself and just, well, GUIDED.
PHD did not control your imaging camera. It did not process images. All it did was autoguide, either through an ST-4 port or a serial (RS-232) port on the mount. It supported a lot of guidecams and CCDs, and was being continuously updated and improved by Mr. Stark Labs, Craig Stark. I used PHD Guiding, a William Optics 66 SD refractor as a guide scope, and the original Meade color DSI CCD cam as a guide cam successfully for several years. But I wasn’t overly happy with the setup aside from PHD.
One thing I didn’t like about it was my guidecam. The color DSI was more than sensitive enough to do the job, but it had a failing: it did not have an ST-4 output. Which meant I had to add an adapter cable, a Shoestring Astronomy adapter cable that converted parallel data from my laptop to the ST-4 switch closures my Atlas mount’s autoguider port understood. Oh, I could have guided from a serial port on the computer to the serial port on the mount hand control, but that still meant another snarfin’ cable plugged into the computer to go with the the DSLR USB cable, the guidecam USB cable, and the DSLR remote shutter control cable. I was kinda tired of the DSI, too; its chip was small. It would have been nice to have a bigger one that yielded a wider field and more guide stars.
Nor was I happy with my guide scope. The WO SD is a fantastic small refractor, but it is also a little on the heavy side, actually heavier than a short tube 80. My rings were kinda clunky, too. They worked, yeah, but they were a little light, and I was pretty sure I was throwing away more frames due to flexure than I ought to be. It was also a bit of a hassle to install the rings and 66 SD for an imaging run.
|My Orion StarShoot|
I was stumped for a while, but then I heard salvation was at hand. Folks over on one of the Cloudy Nights discussion boards were talking about, a Canadian company, KW Telescopes in Ontario, who were selling the combination of a QHY5 autoguide camera (with an ST-4 output), and a guide scope made from a modified 50mm finder. According to the cats and kittens on CN, this system, the QWIQ Guide, was simple and worked well.
I was skeptical. How could you guide pea turkey with that little focal length and aperture? Yeah, I knew guide cameras do not need the obscenely long focal length guide scopes we needed back when we guided by eye, but, still, 50mm? Nevertheless, imagers were reporting the 50mm jobs worked like duck soup with imaging scopes of up to 2000mm focal length. I almost pulled the trigger on the QWIQ, but hesitated. Seemed too good to be true, even though I knew SBIG had produced some workable guide scopes for their cameras with objectives e’en smaller than 50mm.
While I was sitting on the fence about the QWIQ system, I did solve the guide camera conundrum. Orion had begun selling a nice little guide cam, the StarShoot Autoguider, which was very much like KW’s QHY (and was in fact made by QHY). For $279.00. Nice big chip, excellent build quality, ST-4 output, and proven to work with my beloved PHD. Orion even included a copy of PHD Guiding in the package.
I was lucky enough to receive a StarShoot for Christmas 2009 from the wonderful Miss Dorothy. I got the cam out once shortly after I unwrapped it, and it appeared to work well, but… Late 2009 was when The Herschel Project got underway and I put my DSLR away for a while. With nearly 3,000 dim Herschel Objects awaiting me, I hardly used anything other than my deep sky video camera for dang near two years. With the H Project finally under control as of this past fall, though, astrophotography reared its ugly head again as it always does. Yes, I’d get the Canon Rebel out of mothballs, but I wanted to fix my guide scope problem first.
|Orion's version of the QWIQ guider|
Since this set up would be destined for my C8, Celeste, I would have to provide an SCT compatible mounting foot for the finder-cum-guide scope, one which could be had for the not too unreasonable sum of $16.95 (Orion provides a mounting foot with the guide scope, but not with the spacing for an SCT’s accessory holes). That would mean sacrificing Celeste’s original finder, or at least its mounting. But that was OK. Her finder was a well-made Japanese job, but I’d never liked its ring mount. Only its forward ring had adjustment screws; the rear ring had a rubber O ring to hold the finder in place while allowing adjustment. I don’t know if that O ring was just getting old and drying out or what, but the finder would not maintain its alignment for long.
I wasn’t too sorry to see the Celestron finder itself go either. Its polar alignment reticle is not very useful anymore, I rarely use its illuminator, and I like my Orion (Synta) RACI correct image 90 degree finder better. The RACI would fit the mounting foot and would be real sweet on Celeste when I wasn’t using the guider.
In due time the Mini AutoGuider scope arrived, and I was somewhat impressed. It appeared to have been made, or at least professionally modified, for its intended purpose, and included a straight-through 1.25-inch eyepiece holder with three set-screws, a rear dust cap, and the typical “screw-unscrew the finder objective” focus setup. Only minor complaint? Like most 50mm finders, the dewshield/objective end of the tube didn’t extend far enough forward to do much good for either dew or glare.
Getting the original Celestron rings off, the new SCT finder mount on, and the mini-guider installed on Celeste was the work of maybe 15-minutes. It looked super, but how would it work? To find out, I’d need to head to the PSAS dark site in Tanner-Williams. I gave you a report on that run here, but I’d like to go into a little more detail about the guiding end of things.
Set up was easy enough. Mounted the Mini Guider on Celeste, wrapped a 2-inch dew heater strip around its barrel just behind the objective, and inserted the StarShoot camera into the 1.25-inch port. The Mini AutoGuider came with a little parfocal ring to go over the camera’s 1.25-inch nosepiece to allow you to preserve rough focus once you find it. I slid that over the nosepiece. Cabled the StarShoot up, with the guide output on the camera going to the ST-4 autoguide input on the mount, and the USB from the StarShoot to my little netbook, which was loaded up with the latest release of PHD.
First order of bidness was getting the guide camera focused. Brought up PHD and pushed the button that starts the program “looping” images from the guide camera. The Mini AutoGuider’s instructions tell you to focus roughly by loosening the set screws that hold the camera in the guide scope and sliding the camera in and out. I found that unnecessary. Vega was close enough to focus to allow me to get it sharp by using the fine focus method, screwing and unscrewing the objective.
If I haven’t mentioned it already, the instructions that come with Orion’s Mini AutoGuider set up are sufficient. Barely. They do have a serious omission. Nowhere do they tell you you will need to adjust a very important setting in PHD.
The way PHD works is this: you begin looping exposures, and, when you can see a suitable guide star on its display, you press the Stop-sign icon and hit the Guide icon. Before the program can begin guiding on the first star of the evening, though, it must calibrate. It must move the telescope north, south, east, and west to see how the mount reacts. There are several settings under the “brain” icon that concern calibration. The one we are interested in when using the mini-guider is Calibration Step.
This setting determines how long the program will pulse, will move the mount for each calibration step. Normally, with a typical guide scope setup, the default, 750 milliseconds, is fine. With a very short focal length scope like the Mini Guider, it needs to be changed. Leave it as short as it is, and PHD will need to make many steps during the calibration before it sees sufficient movement to complete the process.
Luckily I had read about this need to change Calibration Step on one of the Cloudy Nights boards. PHD might calibrate correctly with the default settings, but it would likely take a long time to do so. By changing the setting to 2000ms, increasing the step size, the calibration completes in a reasonable length of time. The Orion instructions really don’t have much to say about any PHD settings; but this is likely the only one that will need to be changed. If you do need help with PHD, the best place to get it is the Stark Labs Yahoogroup.
|Crop/enlargement of part of M13's field.|
Alrighty then. Clicked on a star close to M13 (the cluster was visible as a fuzzball in the StarShoot frame), PHD calibrated, and immediately began guiding (you know it’s guiding when it puts a green box around the guide star). All I had to do was get the imaging scope going with Nebulosity which I will talk about in greater detail in a blog entry devoted entirely to it. Real Soon. I stared at the netbook screen nervously until the first couple of two-minute subs had come in, “Cool! Nice round stars at f/6.3!” (That’s an enlargement of the star field below.) M13 was way too low in the sky to deliver much in the way of sharp stars, but at least they were round and I got my traditional yearly shot of the Great Glob.
Does that mean every single subframe I took on this evening was perfect? Are they ever? Mine aren’t anyway. I did throw out a few on the three targets I essayed, M13, M27, and M57—but only a few, a very few. It’s a waste to throw away any subframes, of course, so I did some troubleshooting by the light of the next morning.
First thing I did was check EQMOD’s (the program I use to run my Atlas) ST-4 guiding setup. Turned out I’d left the ST-4 guide rates for Right Ascension and declination at EQMOD’s rather low default, “.25,” which, if not crazy, is substantially slower than what I normally use, .50 or even .90. That may have been a contributing factor; we’ll see how it goes at .50 next time out.
Anything else? During the run, I had noticed the cables from the StarShoot, the USB and ST-4 cables, had got awful stiff in the (for us) cold low 40s F temperatures, and had hung up on the scope/mount a time or two. I’ve secured the cables’ to the finder stalk with a Velcro strip, and, again, we’ll see how it goes next time.
Magazine Plug: For once, this is not in Unk’s own self interest. I have never once appeared in Astrophoto Insight. The talents of the imagers who write articles for this superb e-zine are so far in advance of mine as to make my paltry efforts downright laughable. But that is OK. I have learned one heck of a lot from AP Insight. It is a treasure trove of how-tos and reviews. Go get it, campers.
Next time: It’s Ho-ho-ho and mistletoe and presents to pretty girls! As is our custom here, the next blog entry will appear on Christmas Eve rather than on Sunday. See y’all then!
Sunday, December 11, 2011
My Favorite Star Parties: The Chiefland Spring Picnic 2002
With the weather as punk as it can be down here in the Swamp, and the fracking Moon swinging back into view, and Unk not having any observing expeditions planned till after the first of the year, what can he do but take you-all on yet another trip down memory lane? This time to the Chiefland Spring Picnic of 2002. Y’all know something about this one. You've heard me complain about it often enough, anyway. So, if I complain about it all the time, what’s it doing in the “My Favorite Star Parties” series? All shall be revealed, muchachos—eventually.
In 2002 the Chiefland Spring Picnic, which a decade ago was one of two yearly star parties held at the Chiefland Astronomy Village, was scheduled for May. May 10 – 12. That was when my frequent observing companion, Pat Rochford, and I planned to be there, anyhow; some folks, we’d heard, would be down at the CAV at least a week before that doing hard core observing on the cusp of summer.
Pat had spoken to Jeannie Clark, one of the prime organizers of the event, a couple of weeks previous, and she had said she didn't know how many folks to expect, “Could be twenty, could be two-hundred.” That sounded alright to us. Lots of folks on the field would be fun, but so would a small group. The weather forecasts weren't outstanding (“partly to mostly cloudy”), but they didn't sound overly dire for late spring, either. What Mr. Rochford and I didn't take into account, unfortunately, was that other factor in late spring Florida weather, TEMPERATURE.
Not that I’d have let that change my carefully laid observing plans. I was on a mission, you see. I’d just bought a new telescope, a NexStar 11 GPS, Big Bertha, a short time before and had not had a chance to give her a real shakedown cruise. Chaos Manor South’s orange-sky backyard, yeah, Pat’s light polluted observatory, yeah, but out in the real dark, no. I was one antsy little camper to do that.
If Pat and I had checked the Weather Channel, we would have seen that Chiefland, Florida was sizzling, with temperatures well into the 100s F. before figuring in the heat index. That shouldn't have been a problem; once field setup was done, we’d hide out in a cool motel room till sunset. That’s what we would have done if we'd had good sense. But we didn't. We had decided to economize. Who needs a cotton picking motel? A tent on the observing field next to the scopes would be more convenient and nearly as comfortable. Uh-huh.
Come Friday morning, Pat and I loaded up his little Isuzu Trooper mini-SUV and a borrowed U-haul-type trailer with the tons of stuff we considered essential for a star party weekend back in them days. At the time, Pat was still using his home-brew 24-inch Dobsonian (today it’s been replaced by a big Meade SCT); that went in the trailer, suitably padded with sleeping bags and our other camping gear. Bertha rode comfortably in the back of the Trooper in her JMI case. Loaded, we hit the road at 8:15 a.m. for six hours of Interstate-10 and Highway 19. We pushed it as hard as we could with a trailer, since we wanted to be assured of having plenty of set up time—there’d be tents to erect as well as scopes. To that end, we skipped lunch (horrors), in favor of an early supper in Chiefland.
Chiefland, ah, Chiefland. When we hit town I couldn’t help feeling bad for the little burg. It looked as if the mini-recession at the turn of the century had hit ‘em hard. There were lots of empty stores in town and plenty of unworked fields to the south. It took a few years for me to realize that’s the way Chiefland always looks, come economic rain or shine.
Arriving at the CAV, we were some kind of surprised. Jeannie Clark’s words had led us to expect a small crowd. As we rolled onto the Club field, it was obvious there were easily 100 – 150 eager observers already set up with more arriving every minute. It was crowded enough that we had to make several orbits of the field before we found a spot with enough room for the two scopes, the tents, the Trooper and trailer, and us. We were not able to get close to one of the field’s electrical outlets, but that was OK; I came prepared to operate the NS11 completely off batteries. As long as I could get my jumpstart battery (for the scope) and my lawn tractor battery (for the DewBuster) charged during the daytime, all would be well.
All would not be well if we didn't get the picnic canopy up in a hurry. It was now mid-afternoon and the observing field was boiling hot. We needed shade, and we needed it right away. We got one of my old pre-EZ Up canopies erected as fast as possible, fighting tangled tent ropes and lost stakes all the way. When we were done, our little patch of shade made us feel cooler, if far from cool. Still had to get them cotton-picking tents up, though.
I got mine, the Coleman dome tent I’d used at the Texas Star Party a few years before, pitched in record time, but I noticed Pat was struggling. His tent resolutely refused to cooperate. I lent a hand, and got his sleeping quarters up with only a moderate amount of cussing. By now, Pat and I were soaked. Squinting through sweat-stung eyes, I adjourned to my tent to change into shorts and T-shirt and flip-flops. That helped some, but the interior of my tent was already like an oven, and by the time I was dressed my change of clothing was near-about soaked too.
We should have seen the handwriting on the wall, and right then and there should have said, “You know, this just ain’t gonna work. We’ll go straight into town and find a motel room. If we can’t get into the Holiday Inn Express, the Pregnant Guppy Motel (Rod’s nickname for the Manatee Springs Motel) will do just fine.” But we convinced ourselves that a ride into town, a tour of Wal-Mart, and a late dinner/early supper would let us cool off from set up and that everything would thenceforth be fine. We'd only be onsite for two days. How bad could it be? All I can say is we were a little younger and a lot dumber almost ten years ago.
|My picnic canopy helped. A little.|
What then? Back to the field to trot around and visit with friends old and new. I was particularly happy to meet some SCT User Yahoogroup and sci.astro.amateur (if’n you remember what that was) friends in non-virtual space for the first time. As always, it was cool to survey the huge array of scopes our fellow CAVers had brought out. In those days, the Dobsonian was still king at Chiefland, almost to the exclusion of anything else. This was when the Starmasters were riding high, but there were Dobbies of every description scattered across the field.
There were also some cool CATs on the field, including at least three NexStar 11s in addition to Bertha, a brand new NexStar 8 GPS, and numerous LX200s old and new. Particularly attractive was a big TEC Maksutov Cassegrain on a beautiful (no longer made) Millennium Mount. I looked forward to getting a peep through that high-flying bird, but the owner never seemed to do much with it, uncovering it briefly during the day and covering it back up at sundown. Go figger.
Other than mucho hot, how was the weather? It was variably cloudy every day, but it was usually clear enough to allow old Sol to beam down his blistering rays with a vengeance. I slathered on the sunblock, but that didn't make me feel much—if any—better. Yeah, it was a little cooler under the tent canopy, but only a little. Our mighty star’s radiation was being reflected back up off the field and into our faces from all sides. Clouds would actually have been welcome in mid afternoon, but, naturally, they held off till sundown. By the time Sol was out of sight, the clear stretches had assumed the character of the dreaded SUCKER HOLES.
The result was that on Big Bertha’s first dark sky evening I had to cool my heels for at least an hour before a sucker hole big enough to allow me to do a two-star go-to alignment wandered in off the Gulf of Mexico. Today, I take Bertha’s excellent go-to accuracy for granted, but this was all new to me a decade ago, and I was gobsmacked. The C11 pointed north, took a GPS fix, and headed to two alignment stars, which I centered. Took maybe five minutes to do, and for the rest of the evening, and for the rest of the weekend, she put every blessed object I requested in the relatively small field of my 12mm Nagler at f/10 (233x). Wow.
Bertha ready to go, things was looking up. The temperature had fallen a little, to the bearable 80s at least, and the bad, old clouds had changed their minds and scudded off. They returned occasionally over the course of the night, but we were never completely socked in and there was always plenty to see. I got to work, and what work it was. The skies of the Chiefland Astronomy Village are good today, remarkably good, but ten years ago they were just a wee bit darker, and Bertha and I took full advantage of that.
I saw lots of wonderful sights Friday evening. This was the first time in my life I toted up over 100 DSOs in one observing run. I tried to give each one the eyepiece time it deserved, but some got the short shrift. This was, after all, a shakedown cruise, a “commissioning” run, to allow me to see what Bertha could do and how she would do it on a wide variety of objects all across the late-spring/early summer sky.
I did get stopped in my tracks by a couple of wonders. One was the lustrous M5, the great globular cluster in Serpens. As I mentioned last time, a few years before I’d made up my mind that M5 was actually “better” than its famous neighbor, M13, and my view of it on this night just reinforced that. Second best in my eyes that night wasn’t M13, either, but a more distant marvel, NGC 3115, the Spindle Galaxy. In the NS11 on this intensely dark evening, it was amazingly bright, showing traces of the faint nebulous envelope that surrounds its spindle-shaped body.
|This TEC never got used as far as I could tell. Shame.|
With the aid of Volume 2 of NSOG, Bertha and I continued to cruise to target after target. Some familiar, some not so familiar. We did every—well almost every—globular cluster in Ophiuchus. Let me tell you, muchachos, that is a lot of globs. As I said last week, I laugh when somebody opines that all globulars look alike, and my tour of Ophiuchus really gave the lie to that: big, small, bright, dim, odd shapes, and “normal” globes of stars; they were all there.
As the clock ticked on to midnight and after, I just kept going, Bertha quietly humming and delivering. I was particularly taken by the NexStar hand controller. It was so simple to operate that when I got The Stupids at 3 a.m. in those dark days before Monster Energy Drinks, I could still figure out which button to push. Right then and there I decided the real strength of the NexStar 11 wasn’t its high-tech, but its refreshing simplicity.
And so it went until 3:30 in the cotton pickin’ a.m., when it began to cloud up seriously. Me and Pat, who’d been pushing his 24-inch Dob hard, took a break to wait for the next clear stretch. When it became obvious that would not happen any time soon, out came the Rebel Yell. After about 4, the sky did look to be improving slightly, but not enough to encourage us to get started again. Around 5 a.m., I finally lay down in my now semi-cool tent. First thing I noticed? Even with an air mattress under you, a sleeping bag on the ground ain’t that comfortable when you are approaching age 50. Second thing? There was a clear patch to the west, and I had a lovely view of the stars of the Dipper plunging into the horizon through my tent’s little screen window. Which was the last thing I saw before I plunged—into a deep sleep.
|The Pavilion where the actual picnic took place.|
Next thing on the agenda Saturday morning was grub. Pat and I had resolved to take our meals in town except for the picnic in “Chiefland Spring Picnic,” which would be our evening meal. Where to? The Huddle House (like Waffle House) beckoned, but we’d been told Bill’s Bar-B-Q did as fine a job on breakfast as they did on dinner and supper. Pat and I, in the company of another couple of visiting amateurs, feasted on omelets that easily violated B. Kliban’s rule: “Never eat anything bigger than your head.”
After that? To Wal-Mart again to enjoy their a/c for a while and pick out our contributions to the Saturday afternoon picnic. I chose, as usual, the most disgustingly butter-cream-frosting-drenched cookies in the bakery. Pat chose a healthy vegetable tray. Go figure. Then it was back to the field, where we tried to keep cool without much success. If it had been hot Friday afternoon, it was H-O-T Saturday. Even Pat and I, Gulf Coast residents that we were, found it almost too much to take. Make that “too much to take.”
We somehow persevered until picnic time. Sitting under the big pavilion, drinking cold cokes and gobbling the barbeque chicken CAV residents had grilled, it was barely possible to keep my mind off the incredible temperatures, which had now passed 110 F. out on the observing field. Eventually, though, the picnic at the Picnic was done, and we slowly headed back to our little patch of shade. I swear, y’all, I thought I was gonna melt.
|The Beast's Dome.|
Sitting there with Tom, shooting the breeze about the astro-business, sucking down the icy-cold co-colas he passed out, poor Unk actually began to feel human again. We probably strained even Tom’s generous hospitality by remaining resolutely glued to the folding chairs he’d set up for us for hours, but—my gosh—we just couldn’t face the thought of going back out into the terrific heat. We stayed undercover until the Sun finally began to sink and the outdoors became, if not comfortable, at least endurable. I’ve been down to Chiefland in July more than once over the intervening years, but it has never felt as hot as it did that May.
Saturday night started out a lot like Friday night. Plenty of passing clouds, with the clear stretches less frequent than the overcast ones. By the time I was finally able to get Bertha aligned, however, it was obvious Saturday would be a better night than Friday. When the sky suddenly and almost magically cleared, I hit the showpieces again: M13, M5, M10, M12, and the rest of the late spring treasure trove. Howsomeever, my main focus this night would be galaxies, and I headed straight for the great fields of Coma – Virgo, where I spent the next several hours.
So enthralled was I by my Virgo haul under these excellent conditions—I almost convinced myself I saw M87’s jet at high power—that I almost forgot to look at that greatest of globular clusters, Omega Centauri. When I caught the big thing just after culmination, it was the only time that night that I wished for a smaller telescope. At 30’ across, the great mass of suns was hard to frame, even in my 35mm Panoptic eyepiece. ‘Twas still a mindblower: tiny and uncountable stars filling the field of my big glass.
Yeah, I had to climb a towering ladder, but it was well worth it for a look at the Antennae Galaxies with this much aperture. You’ve heard people claim the images in their scopes “look like photographs,” but rarely is that true. It was with the Yardscope. The Antennae were bright, but, most of all, amazingly detailed. The dust lane in the Sombrero Galaxy was, it was easy to see, uneven and scalloped along its edges. M5 didn't just look like Omega Centauri had in Bertha, showing a huge number of stars, those stars were dramatically colored: white, orange, and, here and there, blue. I don’t think I’ve ever had a better visual experience with a Dobsonian—well not until the Clarks got The Beast going a couple of years later.
I was honored to sign Tom and Jeannie’s observatory guestbook with, “Thanks for a wonderful time and the wonderful hospitality. I will be back.” And I was. This visit to CAV would be followed by a long, long string of Chiefland trips.
The 2002 Spring Picnic wasn’t quite over yet. There were a few hours of darkness left, and I had yet to see the sight that would be the capper for a trip that was horrible in the daytime and wonderful at night. After my visit to the Yardscope, Bertha and I made another pass on the Coma – Virgo Cluster of galaxies. Not only was I able to see the famous Playing Mice in Coma, Big Bertha even showed a little detail in those distant sprites. But the best view of the trip wasn’t a galaxy and came around midnight when a new batch of clouds had covered the western side of the sky. That forced me back east, to the little constellation, Scutum. After a good, long look at the Wild Duck Cluster, I punched in NGC 6712, a globular cluster I didn't recall having visited before.
I won’t burden you with details, since I raved about NGC 6712 last week. I will just say that the vision of a little knot of a globular star cluster almost subsumed by an enormously rich star field in Scutum is one that will remain with me to the end of my days.
When I was finally able to pull away from Scutum’s remarkable star cluster, after at least half an hour, the clouds had again wandered off, and I resumed my journey across the sky. I carried on till near 4 a.m. before pulling the Big Switch. I hated to do that, even at 4, but I’d only had about three hours sleep the whole weekend, and there’d be packing and the drive home purty early in the a.m. Pat would be doing the driving, but I felt it incumbent upon me to at least try to stay awake during the trip home.
When I look back on this adventure, the phrase that comes to mind is “no pain, no gain.” Yes, it was hot. It was really too hot. Pat and I should never have tried to tent camp on the field. This was, in fact, the last time I set up a tent at any star party anywhere. And yet, it had been well worth the pain. I’d seen what my new telescope could do, which was offer me a surfeit of nighttime wonders that easily outweighed the days’ blistering heat. I’d do it again, I thought, but with a motel room in the mix. Which is just what I did and continue to do to this very day, muchachos.
Yeah it was hot. TOO HOT. I still have pleasant memories of the trip, however, largely because it was the first time I was able to see what incredible things my new scope could do. It was also great to spend some time with the Clarks.
Y'all know I like to play Monday morning quarterback, though... It would have been a nearly perfect trip had I just had the sense to turn to my companion and say, "Pat, it is too hot. It is stupid hot. We're going to town and checking into one of the motels. I have my credit card, I can afford it, and it is my treat."
Sunday, December 04, 2011
My Favorite Fuzzies: Unk’s Globular Star Cluster Top Ten
I am an admitted galaxy-a-holic, muchachos. Nothing fires my imagination like giant island universes shining dimly across the dark light years of intergalactic space. I’ve been one for a while, too, though doing The Herschel Project has further educated me about the beauty of the less visited of these massive night birds and their incredible diversity. Still, there was a time when galaxies were number two on my deep sky hit parade.
“Globs,” globular star clusters, are giant balls of suns orbiting the nucleus of the Milky Way, swinging out into deep space in the course of their enormous elliptical orbits. Some are older and some are younger and some are more massive and some less so, but all are old and huge as we reckon such things. They are typically composed of hundreds of thousands of metal-poor stars, very old suns, fading embers that may have witnessed the birth of the Milky Way itself.
There are exceptions to the above; there are always exceptions when you are talking about the strange and far away deep sky. Some of the largest globs are thought not to be globular clusters at all, but the remains of small galaxies the Milky Way has devoured. And not all globular stars are yellow or red. Most clusters are peppered with “blue stragglers,” old stars who’ve got a second lease on life, maybe thanks to collisions and mergers with other old stars, and blaze away like younguns.
That’s the science, but how do they look? In a telescope with less than 5-inches of aperture, globular clusters are pretty blah: round fuzzy blobs not unlike many of the other deep sky objects a small scope will reveal. Get to 8-inches, though, and their appearance changes dramatically. “Dramatic” is a good word to describe them. Globs are the most dramatic of deep sky objects. In a medium-size telescope, the brightest are shown as what they are, giant balls of stars. Go to 12-inches and the most prominent globs become mind-bending forests of suns, while the dimmer ones begin to give up their stars, too. Increasing aperture just brings ever more globulars into the dramatic camp.
Anyhoo, globs were Unk’s faves for a long time, since he got up the gumption to stop just pining for a 6-inch Newtonian like the expensive Edmund Super Space Conqueror and RV-6 Dynascope and do something about it, home brewing a pipe-mount six. I still like globs, but I don’t spend nearly as much time with them as I used to. If I give a globular more than a glance these days, it’s usually because I’m using it as a focus “tool” when I’m preparing to image galaxies. But even now I sometimes find myself staring in wonder at a far away globe of stars and pushing the shutter release on it in spite of myself.
All globulars star clusters are not created equal. I have to laugh when some (usually novice) amateur says they all look alike. Like people, some are kings and some are peasants. They range from Messiers possessed of too many suns to count, to dim little smudges like the Palomar globs that the biggest scope won’t resolve visually. When you look at them, really look, you’ll find all globular clusters have strange and wonderful features peculiar to them. Which globs show these things best for amateur visual observers? Like anything from butterflies to race horses, “the best” is subjective, but I’ve been looking at globs for a long time, and these are my loves…
Before we begin, we’d better edumacate the greenhorns about the Shapley - Sawyer Scale. What is it? Why should we need to know what it is? In the late nineteen-twenties, American astronomers Harlow Shapley and Helen Sawyer Hogg set out to classify globular star clusters according to their concentrations. The most highly concentrated, “tightest,” clusters are assigned a Roman numeral class of I. The least concentrated, “loosest,” are Class XII. So what? Its Shapley Sawyer class has everything to do with how a glob will look in your telescope. Not only its general appearance in the eyepiece, but how difficult it is to resolve. A Class VI, for example, is way easier to break into stars than a III. Okay? Let’s go glob busting on Unk’s top ten star balls.
How good is it? One Chiefland Star Party, I forgot to look at the Big O till it was nearly too late. It had got so low that it was partially obscured by my tent canopy. On a whim, almost, I sent the NexStar 11 over that-a-way anyhow. Despite me using maybe half my aperture, Omega was still more than spectacular, a great egg of countless teeny-tiny stars. Frankly, this thing is so large, about the size of the full Moon, that you don’t need a big scope to appreciate it. Hell, it looks as good in a 50mm finder as many globulars do in a C8.
My history with Omega Centauri, I’m embarrassed to say, doesn’t go back that far. I just never thought to look at it--it was a SOUTHERN OBJECT, afterall. Till one evening about twenty years ago at our old club dark site just over the Mississippi state line. I was staring at the southern horizon. Hmm… Centaurus was culminating. That fuzzy star, wasn’t that Omega? I sent my 8-inch Coulter Odyssey to it (by muscle power, of course). The result? My fellow observers musta thought I’d gone nuts with all that hooting and hollering.
How far south do you have to be to get a good look at Omega? At its declination of -47, it is above the horizon all the way up to 43-degrees north latitude, but to get a decent view you gotta be farther south. At 31-degrees (Possum Swamp) it is getting there. At 29.5N (Chiefland) it is considerably better. From the keys (Winter Star Party), it is better still. My dream? To see it overhead from southern climes some day. I can scarcely imagine…
2. 47 Tuc(anae) (NGC 104). Magnitude 4, 30’x30’, Class III. “Is it M13 time now, Uncle Rod?” Not yet, Skeezix. Even our number two is much better than M13. Much. Or so I am told. I’ve not yet had the pleasure of feasting my eyes on the cluster that some Southern Hemisphere boys and girls will tell you tops Omega. 47 Tuc (“tuck”), they say, has all the majesty of Omega Centauri, but packed into an area that’s slightly smaller and with a considerably tighter concentration. These things tend to make it a better object for larger telescopes.
The pros are not as concerned about looks as we are, but find 47 Tuc nearly as interesting as we do—or maybe moreso. An amazing 22 pulsars (neutron stars resulting from supernovae explosions) have been found in 47 Tucanae. Why, you may ask, do Omega Centauri and 47 Tuc have primary designations more suited to stars? Because both are fairly easily visible with the naked eye, and early observers mistook them for stars.
One day I will get a look at this thing. But only when I finally get down south—way south, as in south of the equator. With a declination of -72, it’s never above the horizon till you get to latitude 19-degrees north. Add at least ten more degrees to that so it’s more than just over the horizon, and the result is that nobody in the continental U.S. of A. gets a look at 47 Tuc. Dammit. In fact, even at the southernmost U.S. possession, Palmyra Atoll (uninhabited Pacific island), it’s only 14 degrees up. Sigh.
I’ve always liked M5, but like a lot of y’all, I didn’t look at it often. That changed one night in 1998. My friend, ATM Pat Rochford, had just finished converting my much-loved 12-inch Meade Dobbie, Old Betsy, from a plebian Sonotube scope to a more upscale (and easier to pack) truss tube job. I took first light at one of the Escambia Amateur Astronomers’ Association’s dark sites; one that was, if not perfect, at least very good. For whatever reason, I turned Betsy to M5 as her first light object, and was blown away. Hell, it looked way better than M13. Went to M13 and back to M5, and I didn’t change my mind. Ever since, M5 has displaced M13 in my affections.
|The Great Globular|
Reservations? If you are like I was near 50 years ago, a wet-behind-the-ears newbie with big dreams but a small scope, don’t expect too much. At a Shapley-Sawyer rating of V, it is a tough nut for small telescopes to crack. I can’t do it with my 80mm Short Tube refractor. I tried as hard as I could one spring with my ST80 from the fairly good skies of Indian Springs State Park and the Peach State Star Gaze. Pumped the Short Tube up in magnification as high as I could, but nary a star did I see. I can resolve a few of its sparklers with a 4.5-inch StarBlast at 150 – 200x, and my 5-inch ETX MCT delivers the goods big time.
It took me a while to turn on to this southern cluster’s charms, but when I did I was hooked. It’s sitting adjacent to the teapot’s lid, but it is so big and so bright that it burns through all that atmosphere nevertheless. Shortly after I tried the Short Tube 80 on M13 with disappointing results, I hauled it out to my buddy Pat’s observatory where, in less than perfect skies, the little refractor resolved stars in M22 like a champ. If you’ve got a small scope and yearn for globular stars, M22 is where you go.
My experience with M3? I’ve always liked it, but I’ve never longed for it. It’s a good meat and potatoes glob, but I don’t think I’d be wrong to say it’s a little on the blah side amongst the Messier spectaculars. Also, in the days before go-to, it suffered by being a bit of a pill to find. It’s in a relatively star poor area, and it’s hard to know how to approach it. From the east, from Boötes, or from the west, from Coma? I eventually learned the latter is easier. When I did find M3, I was always happy with it, if not crazy happy.
7. M53 (NGC 5024). Magnitude 7.7, 14.4’x14.4’, Class V. If M3 is sometimes ignored, M53 is the forgotten man of the Messier globs. It has three strikes against it. Like M3 it is in the spring sky when amateurs tend to be focused on intergalactic space, it’s a little lackluster at nearly magnitude 8, and it’s somewhat hard for small instruments to resolve at Class V. And yet, and yet… It’s still a Messier, and that means g-o-o-d. If nothing else, this one provides a welcome break when you tire of observing yet another faint fuzzie in Coma - Virgo. You do need 8-inches of aperture before M53 begins to look like much, but when you have at least that you may be surprised at how good it is.
8. NGC 6712. Magnitude 8.2, 4.3’x4.3’, Class IX. Sometimes a globular is great not because of imposing magnitude and size specs, but because of its field. That is true of M71, which we’ll get to shortly, and it is true of Scutum’s NGC 6712. On the face of it, this one shouldn’t be much. It is loose, approaching open cluster loose, it is small, and it is dim, past magnitude 8. One look, though, will knock your socks off; it is in the midst of one of Scutum’s amazingly rich star fields.
I didn’t discover NGC 6712 until 2002. If I’d glanced at it before, I didn’t remember it, and must have seen it from poor skies. It took one evening at the Chiefland Spring Picnic for me to realize this glob is, well, “WOWSERS!” Not that I’d have hunted it down (well, punched it into the go-to hand control) if I hadn’t been forced to work Scutum. The 2002 Spring Picnic’s weather was hot, and it was hazy, and it was sometimes stormy. We had some hours of absolutely incredible skies, but these were frequently punctuated by clouds. One evening when the largest sucker hole was centered on Scutum, I sent my new NexStar 11, Big Bertha, to the glob, took a good look with my 27 Panoptic, and the next thing I knew my buddies were picking me up off the ground. Yes, that good.
9. M71 (NGC 6838). Magnitude 8.3, 6.1’x6.1’, Class XI. In the number nine spot is M71, which is a lot like NGC 6712: a loose globular in a rich star field, this time in Sagitta. Despite its Messier number, it’s not quite as good as 6712, since it’s both dimmer and looser. Still, what a view! The cluster itself looks more like an open cluster than a globular, and is in a field literally packed with stars. For years, amateurs and professionals (some of ‘em, anyway) wondered whether this wasn’t really a rich M11-like open cluster. But one look at its color - magnitude diagram shows M71 to be old, very old, and it is indeed a member of the glob ranks.
I can’t remember a time when I didn’t love M71. This was one that, unlike M13, my humble Palomar Junior 4.25-inch Newtonian could resolve from the OK but less than perfect skies of Mama and Daddy’s backyard in the 1960s.
The attraction for me as a sprout was not seeing M15’s stars—I couldn’t—but that it was so bright and easy to find. As the years went on and we learned about black holes and the pros began to wonder whether there might be one at this glob’s heart (they’ve gone back and forth on that a few times), this mysterious globular just became more intriguing. My best view? There’ve been many, but maybe the most memorable one was the night I set up my new 12.5-inch Dobbie in the uber light polluted backyard of Chaos Manor South and turned her to M15. Old Betsy blew this one apart and into stars without even breathing hard.
11. NGC 2419. Magnitude 10.4, 6.2’x6.2’, Class II. Yeah, I know this is eleven, but I figured I am due one more since I ain’t actually seen 47 Tuc. The problem? Which one? Wasn’t M2 entitled? Howsabout M92, my fave underappreciated globular? Or the weird looking M30? When the rubber hit the road, I decided on the offbeat, which is thisun in spades.
The Intergalactic Wanderer, as it is sometimes known, is definitely out in left field. Waaay out. Not only is it in a seldom visited constellation, Lynx (Unk has spent considerable time there tracking down Herschel galaxies), it is far, far away. NGC 2419 is one of the most distant globulars known at 91.5 kiloparsecs out in space—beyond the Magellanic Clouds. In fact, at one time it was thought not to be bound to the Milky Way at all—hence the “Wanderer” bidness. That wasn’t true, it turned out. The globular is indeed orbiting the galaxy, but what an orbit. It takes three billion years to complete one trip around the Milky Way.
I’ve looked at this one a bunch of times, starting when I read Scotty’s column about it in a long ago “Deep Sky Wonders” and was intrigued. And I’ve always been fairly satisfied with it. Yeah, it’s dim and it’s tight, but my C8, Celeste, easily teased a few stars out of it at the Deep South Regional Star Gaze a couple of years ago.
It’s the fate of top-ten list makers that nobody ever agrees with them. And I don’t expect you to agree with all my choices, much less my rankings. What I want to know is what you think. You can add comments to this here blog, you know, and I’d be very pleased to see your Best of the Best.
Next time: Come with Unk to the hottest star party ever.