Sunday, January 27, 2013


The Polar Alignment Party

This Sunday morning, muchachos, you Dob and alt-azimuth mount users can sit back, have a cuppa Joe, and be glad you don’t have to join our little party. If you are an equatorial mount user, though, especially a new equatorial mount user, you’d better listen up, since the dreaded polar alignment will be a fact of life for you to some extent even if all you want to do is a little casual visual observing.

First things first, I reckon. If you read my epistle on German equatorial mounts not too long back, you know an equatorial mount is needed to track the stars without field rotation. Oh, you can use gadgets like field de-rotators to make alt-az mounts accurately track the course of the stars across the sky, but such things are expensive, finicky, and have yet to catch on with amateurs for those reasons. That means most of us doing imaging or other things that depend on accurate tracking use an equatorial mount of some kind. For an EQ mount to be able to track satisfactorily, it must be set up correctly. It must have its right ascension (east-west) axis aimed at the celestial pole.

“The whosits of the whatsits?” If you are a novice, or are just new to the world of equatorial mounts, here’s the straight poop. The stars move across the sky because the earth is rotating. To counter that rotation, an equatorial mount must have its right ascension axis lined up with the axis of the earth. Where the heck is that? As I tell my freshmen astronomy students, the easiest way to understand how the sky works is to exercise Suspension of Disbelief. For a minute, let’s consider that old Ptolemy and his bubbas were right: the sky is a huge crystalline globe surrounding the Earth.

The lines on the globe of the Earth are all repeated on this sky globe. If you extend the equator of the Earth onto the sky globe it becomes the celestial equator. Lines of latitude become lines of declination. Lines of longitude become lines of right ascension. AND…if you extend the axis of the earth into the sky globe, it becomes the Celestial Pole, "hitting" the sky globe at a spot near Polaris (North Celestial Pole) or Sigma Octanis (South Celestial Pole).

While it’s the Earth that is rotating, from our perspective it appears the sky globe is what’s turning, and that it is rotating around the Celestial Poles. That being the case, if we could line up a mount so one of its axes is parallel to the Celestial Pole’s axis, and drove it at a speed matching the sky globe’s rotation speed (23-hours, 56-minutes, 4-seconds per revolution), an object would seem to stand still in the telescope.

Part of the equation for good tracking is the motors, gears, and computers, that drive the right ascension axis, but aligning the mount with the Earth’s rotation axis by pointing that R.A. axis at the North Celestial Pole is just as important or moreso. If you are “off,” the scope will not track precisely, no matter how good the gears, with objects drifting in declination (mostly). OK, so how do you do this “polar alignment,” and how cotton picking accurate do you need to be? Glad you asked.


No matter how accurate polar alignment needs to be, start by roughing it in. You can do that one of two ways. If you are antsy to get started and it’s still daylight and you don’t have a prayer of seeing the pole star (or it is behind a tree), you can rely on a compass and on the “latitude” scale on your mount. Begin with the mount/scope plunked down roughly facing north (or south for you Southern Hemisphere boys and girls) and the tube of the scope at 90-degrees declination. If you’re using a fork mount scope, the tube will be parallel to the arms of the fork. If you’ve got a GEM, the tube will be parallel to the mount’s R.A. housing.

All set, loosen whatever you’ve got to loosen to move the RA axis in altitude (tilt). If you are using a wedge-mounted fork SCT, that usually involves several bolts. If the wedge doesn’t have fine latitude adjusters, hold onto the fork so it does not flop down when you loosen those bolts. If you have a GEM, what you usually do is loosen one bolt, the one on the “north” (if you are in the Northern Hemisphere) side of the mount. That will allow you to turn the “south” bolt to raise/lower the R.A. housing to point at the pole.

When you can adjust the mount in altitude, observe the scale that almost every GEM and wedge has, and tilt the RA axis up or down until the pointer is on your latitude.  When you are done, lock the altitude adjustment.

Now it’s time to align in azimuth. If you have a wedge-mounted SCT, you either loosen a single central knob on the threaded rod that fastens the wedge to the tripod (Meade) or the bolts that hold wedge on tripod (Celestron). Get the compass out and observe where north (or south) is. Stand back from the scope far enough so the needle is not affected by the mount’s mass of metal, and eyeball the fork or R.A. housing’s position with regard to north/south. Need to go a little left? Move it left a little in azimuth. A little right? Do that.

Most GEMs have a pair of bolts that push against a post on the tripod. Screw in the bolt that moves the rig in the desired direction while unscrewing the opposite number. A wedge is either just manhandled left or right (sometimes, like the old Celestron Celestar, by nudging the tripod) or with an azimuth adjuster that pushes the wedge right or left.

After that? That's it. Rough polar alignment is done. How rough is it? You might get lucky and be dead-on, but likely not. What you will usually get is “good enough for visual.” You will have to mash a north or south button or turn a slow motion control once in a while to keep an object centered as it drifts in declination due to the less than perfect polar alignment, but it will not be too bad. If it is too bad, you can wait for dark and do a better rough alignment.

A better rough alignment requires one thing: that you be able to see the pole star. In the north, that’s easy unless there are obstructions. Polaris is magnitude 2 and stands out like a sore thumb as darkness falls.

In the south, the pole star, Sigma Octanis (or “Octantis” if you prefer), is not as hard to find as reputed. It is at magnitude 5.5 or so and is visible in a finder or even in a polar alignment scope from all but the worst locations. Not sure which star is Sigma? It forms a little parallelogram with Tau, Upsilon, and Chi Octanis.  Wait for sufficient darkness before looking for it, of course, and have a finder chart at your side or a laptop running Cartes du Ciel or another planetarium program.

What do you do with the pole star? You center it in the telescope’s finder (or in the polar alignment borescope in a GEM). If your GEM does not have a polar scope in its RA housing, just center Polaris in the hollow bore. Unless your eyes and skies are pretty dern good, you will have to use the scope’s main finder for Sigma.

What does this better rough-in get you? Tracking most assuredly good enough for most visual applications. It will not be perfect, since Polaris is about ¾-degree from the true North Celestial Pole, and Sigma, which occasionally goes by the name “Polaris Australis,” is about 1-degree from the South Pole.

While the two rough methods are good enough for many purposes, if you are imaging or doing very high power visual observing you will have to do better. Where does that better start? If you have a GEM, it starts with a GEM mount’s polar borescope.

More Better Gooder

A GEM’s polar finder is a simple device; it is a little refractor inserted through the hollow R.A. axis of the mount. It will have a special reticle that may have pictures of constellation stick figures etched on it, or just a crosshair and a small circle where Polaris goes. Most polar scopes have reticles that also accommodate Southern Hemisphere observers.
Rough-in the telescope as above, and remove the fore and aft lens-caps from the mount’s R.A. housing. You will have to turn the telescope (or just the mount’s saddle if the scope ain’t on it yet) until it is perpendicular to the R.A. axis of the mount in order to open up a hole in the declination shaft for the polar scope to look through.

How do you do the actual alignment? There are several possibilities. You can use the etched constellation figures, if any. Undo the R.A. lock and rotate the mount in right ascension until the constellations in the polar scope roughly match their positions in the sky. Note that the constellation etchings (usually Ursa Major and Cassiopeia in the Northern Hemisphere) will not be able to be overlaid on the real constellations, which will be too large to fit in the view of the polar scope.

Just eyeball the real things in the sky and match their rotational orientation as well as you can. When done, lock the R.A. axis, and use the mount’s altitude and azimuth adjustments to put the pole star in the circle on the reticle where it is supposed to go. Be sure to tighten down the mount’s altitude and azimuth so you don’t lose your nice alignment.

The “match the constellations” method is better than just centering Polaris, but it’s not overly accurate, and if you are going to the trouble of using a polar scope, you should aim for "much better than roughing in." You can get that by using the special scales found on most polar scopes. The manual that came with the GEM will have instructions, which will include directions for making corrections depending on a site's position in its time zone and stuff like that. Stuff that is confusing for beginners and everybody else. Luckily, there is a simpler way. 

The simpler way uses the right ascension setting circle and Polaris’ (or Sigma’s) “Local Hour Angle.” Hour Angle is a sort of time that indicates the position of the pole star with regard to the true pole. To use the LHA method, rotate the mount in R.A. until the circle (or other marker) on the polar scope reticle where Polaris goes is on the bottom. If the reticle has a crosshair above the circle, you can get it exact by centering the pole star in the crosshairs and using the altitude adjuster to run it up and down a crosshair till it stays precisely on the line. When the marker for the pole star is at the exact bottom, lock the mount in R.A. and set the R.A. setting circle to “0” hours.

Now, find the current hour angle of Polaris. How do you do that? If you are using a Synta SynScan mount (like the Orion Atlas EQ-6), its hand controller will display LHA after you enter time and position. If you are not? Some planetarium programs, including ever'body's fave, Cartes du Ciel, show LHA (click on Polaris and bring up the information window for it). So do Polar Alignment helper programs (more on them in a minute). There are even iPhone programs that display Hour Angle.

When you have Local Hour Angle, undo the R.A. lock and rotate the R.A. axis of the mount until the reading on the right ascension setting circle (usually the upper scale in the Northern Hemisphere) is the same as the current LHA. If LHA is 14:30, move the mount till the R.A. under the pointer is 14 hours 30 minutes. Lock the R.A. axis again and use the altitude and azimuth adjusters to move Polaris to the spot where it goes on the reticle. When done carefully, the LHA method will produce an alignment good enough for at least 5-minute exposures at medium focal lengths.

Potential gotchas? Be sure the polar scope is correctly aligned with the mount (see the manual, natch). Newbies: some of y’all assume you turn the polar scope in its housing till the reticle is properly positioned. Nope. Like I been saying, you turn the whole shebang by undoing the mount R.A. lock and rotating in right ascension.

I like the LHA method of polar alignment a lot, but there is another way to use a polar scope that is also quite accurate. That is the “Kochab’s Clock” procedure of my old buddy Doc Clay Sherrod. If you have a GEM (and, natch, live in the Northern Hemisphere), this is an easy way to get the Polaris marker in your polar scope properly positioned. With the mount pointed north and ready to go, find the bright 2.08 magnitude star Kochab, Beta Ursae Monoris. Undo the R.A. lock, and rotate until the star is “on” an imaginary line drawn from the declination counterweight bar (or on the top edge of the bar itself). Lock R.A. Move the mount in altitude and azimuth until Polaris is in the correct spot. For full instructions, see this nice page.

“All that’s cool for GEMs, Unk, but I got me a Meade 2080 SCT that ain’t got no polar finder.” A few companies used to sell add-on polar scopes for forks, but all of them appear to have discontinued these alignment tools, including the last holdout, Jim’s Mobile. Quite a few SCTs from the 1990s and before had polar alignment reticles built into their normal finder scopes, which can be used with polar alignment helpers to produce OK alignments.
But if the fork has no polar finder, Doc Clay has a somewhat more complicated but very accurate Kochab’s Clock alignment for fork users that can be found here.  It can potentially be used with any SCT finder, even one without a polar reticle. While this take on the Kochab Clock works very well, I would guess that today most fork users, those with computer go-to mounts, anyway, are using the hand control to produce a good polar alignment.

Hand Paddle Polar Alignment

Need to kick it up at least part of a notch in accuracy and a big notch in “easy”? Some mount makers, most notably Synta/Celestron and Losmandy, have been incorporating polar alignment routines into their hand controls for a while. It works like this:  you do a go-to alignment after doing a “rough in” polar alignment as above, and tell the mount you want to polar align. It has you select and go-to a star. The mount then points at where the star should be if polar alignment is perfect. All you’ve got to do then is center up the star using the mount’s altitude and azimuth adjusters.

The good? This alignment method is quite accurate, at least as accurate as a polar scope alignment, and often somewhat better. There’s no kneeling down on the cold hard ground to peer through that consarned polar scope. And, to top it all off, go-to computer alignment is as useable with a fork-wedge scope as with a GEM.

The bad? While you have a lot of alignment choices other than Polaris or Sigma, which is a god-send for folks with a blocked northern/southern sky, you can’t really, as Celestron suggests with the name for their polar alignment process, “AllStar,” use any star. To begin with, they recommend against Polaris, and while you can use any other star, theoretically, when you get away from the area near the intersection of the Celestial Equator and the Local Meridian, it becomes a bear to center a star with the alt-az controls. All in all, though, automated polar alignment for go-to mounts is a big advance.

What if you’ve got a go-to, but it ain’t a Celestron or a Losmandy and doesn’t have a polar alignment feature? All is not lost. You can use another accurate computer method that will work with any mount that has a “sync” function in its hand control. This process, “Iterative” alignment, is not as quick as AllStar but is at least as accurate. Its only potential drawback is that you must be able to see Polaris or Sigma.

It seems a little complicated the first time out, but once you’ve done "Iterative" a couple of times, you'll find it is easier than drifting, more accurate than a polar scope, and good enough for all but the very longest imaging integrations. To begin, rough in the polar alignment as always, go-to align the scope (some folks advise a 1-star alignment), and go-to a star. The only criteria for star selection is that it be at least 90-degrees from the pole star in declination.

When you’ve picked and done a go-to to the star, center it up with the hand control and SYNC it. Then, go-to Polaris (or Sigma). Don’t sync here; use the alt-az adjusters to move the star HALF the distance to the center of the eyepiece. Next, go-to the alignment star again, center it with the HC buttons and sync, go back to the pole star and move it half the distance to the center once more. Keep going back and forth till Polaris (Sigma) is dead center after a go-to. When it is, you are done and have a very good alignment.

You are one of my brothers or sisters who take loooong exposures? You, like Rod, stack your “subframes” into a final image, but unlike Unk’s 2 – 5-minute “subs,” yours are half an hour long or longer? If that is you, you need an exact polar alignment to prevent field rotation over lengthy exposures. Yep, you gotta drift align, as in “use the declination drift method of polar alignment.”

The Best

Some folks, including Unk, who don’t have observatories and must polar align every time, don’t have the patience to do a drift, but in truth it ain’t that bad. After you’ve done it a couple of times, you can probably be up and aligned in 30-minutes, and it gives you something to do when it’s still too light to start taking pictures. What do you need to do a drift? Just an illuminated crosshair reticle eyepiece and a clear view to the south and east (or west). You will want a magnification of at least 150x or so, but there is no need to go to crazy high powers. What kind of mount will work for a drift alignment? Any kind of equatorial. A fork’s wedge must have fine adjusters, but that is the only caveat.

OK, let’s drift. At least rough-in the polar alignment; the closer you get to the pole, the shorter your drift time will be. Pick a star that’s near the Local Meridian and about 10-degrees from the Celestial Equator. Center that star in the reticle and rotate the eyepiece (and position the diagonal and yourself as required) until moving the mount’s declination adjustment drives the star up and down a crosshair. Re-center the star and you are ready to go.

Let's drift:  watch the star. If it moves up (north), adjust the mount alt-az control that will move it right. If it goes down (south), move it left. After a move, center the star again and watch for more drift. How much should you move the star? I generally move it about the distance it has drifted. Keep doing this until there is no drift for 5-minutes. You may see east-west movement due to your mount’s periodic error, of course. Ignore it or guide it out, your choice.

OK, on to star two. You can use a star on either the east or west horizon. Whichever you choose, set the eyepiece/diagonal up so the star moves up or down a crosshair in declination as before. For a star ten degrees above the east horizon, if it drifts up (north), move it down. If it goes down (south), move it up. The instructions are slightly different for a star in the west.  If that star drifts up, adjust altitude to move the star up. If the star drifts down, adjust altitude to move it down. As with the Meridian star, keep going till there is no drift for five minutes.

What then? You are done and have a polar alignment good enough for long exposure work. Do note that some people suggest checking the Meridian star again after doing the east or west star, but Unk is usually way too impatient for that.

Drift alignment works just as well in the Southern Hemisphere as it does in the Northern Hemisphere, but the instructions are a little different. See this excellent article for details. Which also has considerably more detailed Northern Hemisphere instructions than the above.

What's that? I see a raised hand in back:  "Unk, how come you ain't said nothing about leveling the scope's tripod before polar alignment?" Well, there's a reason for that, Skeezix—it ain't necessary. The level or lack thereof of the tripod will have exactly NO effect on the quality of a polar alignment. Having the tripod reasonably level, can make it a little easier to do a drift alignment; it may make doing a check of the second star unnecessary since there will be no "interaction" between altitude and azimuth moves, but that is it. Don't waste a lot of time leveling.

PC Help

This being the computer age, the age of PCs on the observing field, there are, as you might expect, computer programs that help with polar alignment. These can be as simple as polar align helper programs that show where the pole star should go on a polar scope reticle and give LHA like my fave from the good folk at Takahashi (this page can be saved and run on your computer without an Internet connection, by the way). But some go a lot further, basically automating the polar alignment process.

There are methods for using CCD imaging programs to aid in drift polar alignment, or, hell, even using PHD Guiding to get you on the pole. But there is also software expressly designed for polar alignment. There are quite a few polar alignment softs out there now, including WCS, PoleAlignMax, and EQ Align. The most developed program of this type, though, is probably Matthias Garzarolli’s AlignMaster. What it does is kinda like AllStar and kinda like Iterative. It slews to two stars, calculates misalignment data, re-slews to the second star, and has you center that using the alt-az adjusters. Unlike some similar utilities, you don’t need a camera on the scope for alignment, just a reticle eyepiece.

I tried AlignMaster with my Atlas mount, and was quite impressed. It seemed to yield very good polar alignments, certainly good enough for my modest requirements, will work on any mount that is ASCOM compatible, is available in a free 30-day evaluation version, and costs a modest 20 bucks. If all my mounts did not have built-in polar alignment routines (thanks to the latest SynScan firmware upgrade I now have AllStar for my Atlas mount), you can bet I’d have AlignMaster on my PC.

And there you have it, polar alignment. Yeah, it sounds like a pain, but it ain’t really. Remember, for visual work a quick roughing-in is all you need, and even a drift polar alignment should be duck soup after a few outings. And maybe it will be for you. I wish I’d been able to convince myself of that back in the day. My album of film deep sky shots would probably feature a lot more with round stars if I had. But I just didn’t like to drift then, and I don't like to drift now. Thank god for today’s shorter exposures AlignMaster, AllStar, Iterative, and Kochab’s Clock is all I can say, muchachos.

Well Deserved Plug Department:  You've probably bought something or other from JMI, Jim's Mobile Industries, over the years. How could you not? They make everything from simple counterweights to gargantuan telescopes. They were good way back when, and they are good now, campers.

As y'all know, the JMI Motofocus, which I use on both the C8 and C11, is indispensable when your old Unk is going after the dim stuff. So you can imagine how upset he was when the C8's Motofocus installation developed a problem after years of faithful service.

To make a long story short, JMI helped me, helped me right away, and made Unk both happy and relieved. The Motofocus is a must-have for chasing those pea-picking Arp galaxies as I am doing now. Couldn't ask for more than the excellent support I received. People say they are worried there aren't many U.S. gear manufacturers left, and wonder what to do about that. Well, I'll tell ya, JMI is still around.  Support them as they have supported us over the years.

Next Time: Tick Tock Clock...

Sunday, January 20, 2013


The Herschel Project (Slight Return) and O.A. Nights 1 and 2

 Mr. Wolfe says you can’t go home again, muchachos, but I feel like I have done just that. “Unk, what in tarnation are you going on about now?” What I’m going on about is me and Miss Dorothy’s just finished expedition down to Florida and the Chiefland Astronomy Village to revisit some of the spring Herschels and start a new observing project. Being back on the good, old Billy Dodd Memorial Observing Field chasing Herschels again dern sure made me feel like I had come home.

Dorothy and I originally talked about making a CAV run in December, but a couple of things intervened:  the holidays—the new Moon would come just before Christmas—and the fact that the Herschels I wanted wouldn’t rise till pretty cotton-picking late in December. How about January, then?

I’ve been down to the CAV in January 'most every year, with a couple of memorable after-New Year’s expeditions coming to mind. Besides “which month?” there was also the question of “which days?” Wednesday - Sunday or Thursday - Sunday? Don’t know why I told D. “Thursday” instead of “Wednesday,” trimming off my usual fourth day, but I did. Hoped I wouldn’t live to regret that if a Thursday – Saturday skunk-out struck.

I loaded up our 4Runner, Miss Lucille Van Pelt, the night before, Wednesday night. That makes departure morning oh-so-much more pleasant. What did Unk load? The NexStar C11, Big Bertha, natch. I’ve used her more than any of my other telescopes down Chiefland way. Yeah, she’s on the heavy side for me these days, but the observing field payoff is well worth a mite of huffing and puffing. What else? Mallincam Xtreme, Orion digital video recorder, laptop, assorted equipment cases, EZ-Up canopy, observing and camp chairs, suitcases, eyepiece box (just in case)—you get the picture.

Even though the weather goobers appeared to be promising unseasonably warm weather, Miss D. and I ran by Bass Pro the Saturday before our trip and picked up bottles of butane for the Black Cat heater and thermal socks for Unk’s footsies. In addition to warm temps, the goobs were predicting partly cloudy skies for the duration, but I wanted to be able to go all night (which is 3 a.m. for your aged Uncle) in relative comfort if the weather became more seasonable and the skies cleared out.

Wednesday morning we were up early and raring to go, bettering our standard departure time of 8 a.m. by a few minutes. First stop, as always, was the neighborhood Mickey D’s for a healthy breakfast—as such things go at Macdonald’s—for D. and a fried chicken biscuit and hashbrowns (well, that’s what they call ‘em, anyway) for moi. Getting breakfast means we can drive straight through without lunch, which is vital this time of year when darkness comes too early, usually before Unk is ready for it.

Miss Dorothy and I cruised down I-10 to the accompaniment of Sirius XM’s Real Jazz Channel. If you do much driving and don’t have satellite radio in your vehicle, think about getting it; it makes both road trips and daily commutes mucho more enjoyable. How did the sky look as we traversed the Sunshine State? When we left The Swamp it was not only cloudy but slightly foggy, and it felt as if really bad weather might be on the way. The closer we got to our turnoff just past Tallahassee, however, the more the clouds scudded off.

When we stopped at the old Sunoco station at the Highway 19 (Florida - Georgia Parkway) exit, Unk turned a critical eye on the sky. The verdict was “not perfect, but…” I wasn’t ready to say I’d be huntin’ Herschels all night long, but there was never any doubt Dorothy and I would at least be able to set up the gear. Miss Van Pelt fueled for the final run-in to Chiefland, and Sasquatch Big Stick purchased for Unk, we hit the last 100-miles with a will.

No matter how the weather looks, we always stick to the hallowed Plan:  check into the Day’s Inn, head to the site for equipment set up if it ain’t raining, back to town for a supply run on Wal-Mart, early supper, quick stop by the room, and out to the field for, if’n we are lucky, a long night of deep sky voyaging.

That is just what we did after a bit of delay at the motel. The room we were given did not pass muster. Say what you will about the dadgum Chiefland Day’s Inn, the rooms there are usually clean. The one we got this time, though, well…STANK. Literally. It had a strong musty odor that slapped us in our faces when I opened the door. Back to the office for a change of room, one on the north side rather than pool side this time, which was fine. We unpacked and skedaddled for the CAV.

It being Thursday, I was not surprised to see quite a few of my fellow Chiefland Observers already onsite. After saying “hey” to John and Bobbie, Carl, Paul, and other good folk I see way too infrequently, we got to work. Up went the scope and the EZ-Up and out came the multitudinous gear boxes. After we were done, it was very pleasant hanging out with our friends in the warm (mid 80s, y’all) afternoon air and shooting the breeze, but it was already 4 o’clock and we had that Wal-Mart trip and supper to do.

Our WallyWorld visit was a record-breaker time-wise, with us in and out in 20-minutes. What did we get? Same-old, same-old including Jack Link’s beef sticks for field snacking, granola for the same thing in slightly healthier fashion, Kolorado Kool-Aid for after run relaxing, and a new Star Wars T-shirt to add to Unk’s collection. Thence to Taco Bell for supper. I wasn’t too hungry, maybe because the quickly setting sun was making me nervous, so I settled for a couple of standard tacos rather than the awesome Dorito Taco Supremes I normally favor.

I hate being rushed setting up, but there was simply nothing for it. Back on the field, I scurried to hook up the scope’s and computer’s and monitor’s myriad cables including the NexRemote line, the video cable for the Xtreme, the serial cable for the Xtreme, the wire for the scope’s Motofocus, and power for computer, telescope, and video monitor (my portable DVD player). Figgered I’d better get the DewBuster cranking, even though a steady breeze seemed to be keeping the after-sundown dew at bay. Finally, plugged my Orion StarShoot digital video recorder into the switch I use to route video to either it or the monitor. By the time I was done it was well and truly dark.

It had been a long time since I’d been able to use the Mallincam—months—but the original software that shipped with the Xtreme is simple to use, and I had no trouble lighting off the cam and getting a set of crosshairs overlaid on the monitor. Telescope? You-all will not believe it, but I did the same thing I always do; I started NexRemote and tried to connect to Bertha before I turned her on. I didn’t fiddle around, just rebooted the computer, turned the NS11’s o-n/o-f-f to o-n, and that was that.

Alignment went without a hitch. Bertha didn’t try to imitate a manic Ferris wheel during “finding level” as she sometimes does, she just leveled, found north, and went to Capella, the first of two alignment stars. I centered The Goat Star—the Xtreme-generated crosshairs are a huge help—and did the same for star two, Aldeberan. “Alignment success,” Bertha intoned via NexRemote. I never have any trouble with go-to accuracy on the NS11; she will invariably put anything I ask for on the small Xtreme chip, but I thought I’d send her to a “check” object before getting started on the night’s list.

My rear cell setup would be a little different this time. Usually, I’ve either had the Stellacam 2 in a visual back screwed directly onto a Meade f/3.3 reducer on the SCT’s rear port, or I have had a Celestron f/6.3 on the port, a diagonal after that, and the Mallincam with an f/5 reducer on its nose inserted in the diagonal. In alt-az mode, the Xtreme, which is longer than the Stellacam, will hit the base of the scope when it is pointed anywhere near the zenith, so a star diagonal is necessary.

Tonight would, I hoped, be mostly small galaxies, so I dispensed with the combined f/6.3 and f/5 reducers. Instead, I screwed my SCT style William Optics diagonal directly onto the scope’s rear port, inserted the f/3.3 reducer into the diagonal, screwed a visual back onto that, and slid the Xtreme, sans f/5 reducer, into that visual back. “Now hold on, Unk. How in hail did you insert a Meade f/3.3 reducer into the eyepiece end of a cotton-picking star diagonal?”

Easy, Skeezix. Easy with the addition of an accessory from Jim Henson’s, his 2" Eyepiece Barrel to Schmidt Thread Adapter. What that is is a 2-inch tube with SCT threads on one end. Screw the 3.3 (or any other SCT accessory) onto that end and slide the whole works into the diagonal. Simple, elegant, allows me to use the Meade f/3.3 with a diagonal (the camera will not reach focus if you put the reducer ahead of the diagonal).

Only downcheck? I do not get as much reduction in this mode as I normally do. With the reducer set back from the rear port a fur piece, I’d guess the focal ratio is around f/5. Which was OK for small galaxies, though it didn’t produce images of diffuse nebulae as smooth and pretty as I am normally used to with the Xtreme. There are always tradeoffs in amateur astronomy.

Thursday Night:  Catch as Catch Can

Alignment done, I sent Miss Bertha to M35’s tiny companion cluster, NGC 2158, for a test of her go-to accuracy at this longer than accustomed focal length. NGC 2158, which is composed of tiny, tiny stars, is also a wonderful focusing aid. Entered “2158” in the virtual hand control on the Toshiba laptop’s screen and away we went. When Bertha announced “target acquired” and the Xtreme’s exposures caught up with her, there was the cluster, dang near centered. Cool. Now to focus with my JMI Motofocus remote.

I tried to focus, anyway. Clouds, dadgum clouds, had begun rolling back in in substantial numbers shortly after sunset. I did the best I could, mashing the JMI paddle to get the stars as small as possible in 7-second exposures. When I was done, I figured “good enough for gubmint work.” Unless something changed in a right quick hurry, it didn’t look like we’d get much on this night anyway.

We didn’t. Orion’s area of the sky was in the semi-clear every once in a while, so I hung out there. M43 was a real wonder. At f/5 or so, it filled a substantial part of the screen, showing off countless dark lanes. Had to do the Horsehead, natch. It was OK, but was subdued in the building haze, even when I bumped the exposure up to 56 consarned seconds.

The clouds would come and the clouds would go. I took frequent breaks, schmoozed with my mates, and headed to the clubhouse for the occasional Monster Energy Drink, trying to hang in until the sky stopped teasing and decided whether it wanted to open up or close down. Nothing changed. I revisited the Horse a time or two, but it was never very good.

By 11 p.m., Urania’s final verdict was in:  “That’s all for you-all tonight.” With yet another wave of thick clouds in the offing, I threw that accursed Big Switch, hopped in Miss Van Pelt, who I’d parked off the field, and headed down the eerie old lane of mossy oaks and back to Highway 19 and Chiefland. At the motel, it was Kolorado Kool-Aid, Ghost Hunters, and Cloudy Nights. What? No Rebel Yell? Nope. Not a drop. The pea-picking Alabama state store did not have a single bottle of Unk’s fave beverage. I had greater faith in Florida’s package stores, and hoped I could rectify this disgusting want on the morrow.

Friday dawned to clear, if foggy, skies and we were up and about early for a day’s activities that began with a motel breakfast. Unk, you will not be surprised to hear, cooked himself a giant waffle, which he drowned in syrup. At least he only made one waffle and bypassed the sausage biscuits. I keep threatening to take Miss Dorothy across the street for a big old Huddle House breakfast some day, but in truth the Day’s Inn breakfast is sufficient.

Well before noon, we were out of the motel. Unk was fired up—not all my observing goals were celestial in nature, you see. Despite visiting their hangouts every time we’d been down in C-land over the last several years, Rod and Miss Dorothy had never yet seen a manatee. I swore I was going to spot one of the big, friendly aquatic mammals this time.

‘Twas not to be. This is the correct time of year; it’s in the winter that the manatees seek sheltered inlets, but apparently the weather was not right. Too warm to encourage ‘em to head up into the springs, I reckon. The temperature was headed for the upper 80s and would fall only slowly as the day wound down. Needless to say, the butane and thermal socks were never unpacked. Anyhoo, we didn’t see a single manatee despite spending quite some time at Manatee Springs State Park. We did see plenty of fish, turtles, squirrels, and assorted birds as we wandered the grounds surrounding the crystal clear springs. Next time for sure!

And then, and then…it was lunchtime. If you are a faithful reader of The Little Old Blog from Possum Swamp, I don’t have to tell you where we went. If not? I’ll spell it out: Bar B-Q Bill’s. Funny thing? While Bill’s pork and beef are tops with me, I believe it is their salad bar I crave most. No purple lettuce or weird-colored pasta, just the same ingredients Mama put on her table in the 1960s. In profusion. Unk heaped it high, poured on the old-fashioned blue cheese dressing, and topped it off with the crunchy artificial bacon bits he loves. When the Pork Special Plate came, it was almost an anticlimax.

Friday Night and Operation Arp

When Unk left the Day’s Inn at 4 p.m.—a wee bit early because I had got my time-zones mixed up—the signs all appeared favorable. The few clouds that had been touring the afternoon sky had mostly scampered off, and the liquor store, an adjunct to Chiefland’s other barbeque joint, Bubbaque’s, had Rebel Yell aplenty. And, indeed, the night started off strong, even if it didn’t quite stay that way. Computer and cameras were fired up and scope aligned without a glitch and we were “go” for Operation Arp.

“The whosits? The Whatsits?” Operation Arp is Unk’s new observing project, his quest to see all the Arp galaxies—and maybe even do a little more than just that. What’s an “Arp”? If you’ve been in astronomy long, the name Halton “Chip” Arp is probably familiar to you. He is an American astronomer who did most of his work in the 1960s and 1970s, but who is still active today. His most famous accomplishment is probably his Atlas of Peculiar Galaxies, which focuses on 338 galaxies that looked disturbed or strange or otherwise stood out for Arp.

Most of these odd-duck galaxies are in the Atlas because they do not fit in with normal morphological types, with most no doubt being disturbed galaxies, galaxies that have suffered close encounters with their neighbors. That’s just the tip of the iceberg, though; Arp divides his three-hundred plus galaxies into five major groups and nearly forty subgroups, which you can find listed either in his atlas or in the article here. Most interestingly, some of these galaxies appeared to Arp to have spit out quasars.

Back when the Atlas was published in 1966, the nature of quasars, which are now thought to be (extremely) active galactic nuclei in the early Universe, was very much unsettled. Even then, though, the redshifts displayed by these bizarre objects seemed to indicate they were far, far away, much farther away than the galaxies they were paired with in Arp’s atlas. Nevertheless, Dr. Arp was convinced “his” quasars, which sometimes even appeared to have streams of matter connecting them to their “host” galaxies, were indeed something ejected by these larger galaxies.

How did/does Arp explain the discordant redshifts between the galaxies and their supposedly ejected quasars? Largely with the theory that the redshift value of a galaxy is composed of two parts, a velocity component and an intrinsic redshift value inherent in the matter of the galaxy. If you are interested in learning more about Dr. Arp’s theories, have a look at his book, Quasars, Redshifts and Controversies.

Controversial? Darn tootin’, since Arp not only dismisses redshift as an indicator of distance, but the Big Bang theory itself. While he does have his fans, it’s fair to say most astronomers do not put much credence in his theories. Today’s giant telescopes have, after all, revealed some quasars as the centers of very distant galaxies—you can see their galactic disks in Hubble images. Most astronomers are firmly convinced Arp’s galaxy – quasar alignments are nothing more than coincidence, chance alignments.

Whatever you think of Halton Arp’s theories about quasars and the Big Bang, one thing is sure, he has given us a splendid list of interesting and sometimes outré galaxies. It is also a list that can be pretty hard going. Some of his galaxies are easy showpieces like M51, but many of them are way too small and distant to have been included in even the NGC catalog. If you start the Arp list, you will soon be hunting Markarians, LEDAs, and PGCs.

Which put the complete Arp list beyond the reach of amateur astronomers till fairly recently. Then things changed. Huge Dobsonians came to the observing field, insanely sensitive deep space video cameras got into amateur hands, and the combination of the two made “too dim for amateur scopes” a thing of the past.

Not that you need a gigant-a-normous Dob to see all the Arps. A C8 will do it with a sensitive enough camera and long enough exposures. Yes, there are some terribly dim ones, but the dimmest also tend to be the smallest, so that even a magnitude 16 Arp won’t be much challenge for a Mallincam. At not much bigger than fuzzy stars, these teeny-weenies show up easily. Dimmest object in the catalog? Arp 211 at magnitude 18. Will that be beyond Unk’s C11 and Mallincam Xtreme? That is one of the things I want to find out as Operation Arp goes on.

If you decide to follow me onto those distant Arp fields, you, like me, will need some help. In addition to the Atlas itself, there is an excellent book by Jeff Kanipe and Dennis Webb, and plenty of good pages on the Internet to help you attack these sometimes frighteningly dim objects. My fave website is this one here.

Why am I doing this? One reason is I need a project. I don’t do much fruitful observing unless I have a list, preferably a big list, to work. Since The Herschel Project has (more or less) ended, I’ve been bereft of one. The other reason is that the galaxies in Arp’s legendary atlas are weird and interesting—and sometimes beautiful.

Gotta have ground rules. What are the ground rules? Unlike the Herschel II part of The Herschel Project, there will not be a time limit. The goal here will not be to dash through the list, picking off as many as possible in one night, but instead will be comparatively leisurely contemplation. I don’t just want to say I’ve seen an Arp; if possible I want to be able to see for myself why an object was included in The Atlas of Peculiar Galaxies. If I have to come back to a galaxy again and again to try to find that out, I will do so. I will share my successes and failures with y’all right here. And that is that.

This first night out, I thought I’d focus on the “easier” Arp galaxies, those with NGC numbers. In addition to the fact that these would be the best targets for what might be a borderline night, there was another reason for confining myself to the NGCs in the list. It had been a long time since I’d had NexRemote’s virtual port working. The virtual port feature allows you to send the scope on go-tos using a computer program like SkyTools 3 (or Stellarium, or whatever) while you are using NexRemote. You specify a “virtual” port, which mimics the serial port on the “real” Celestron hand control.

I had not been able to get the virtual port to work since I switched to Windows 7. But I knew I had to get it going to do the Arps or give up NexRemote. You can’t punch “PGC 12053” into the NexRemote virtual hand control any more than you can punch it into the non-virtual HC. Neither has the PGC (or other obscure or “professional” catalogs) onboard. I planned to reserve Saturday night for tinkering with NexRemote, and figured it would take a lot of tinkering.

Anyhoo, as soon as it was good and dark, I brought up the Arp list on SkyTools 3 and got to work. Please note that an “Arp” may be a single galaxy, or a pair of galaxies, or a whole group of ‘em.

NGC 1253 (Arp 279). At 28 seconds the image was detailed and the companion object easy.  The larger galaxy is 1253, while the odd shaped little feller is 1253A (aka "PGC 12053”).  This is an Arp because of the interaction between the two, I reckon.

NGC 1741 (Arp 259). This galaxy is dim, but looks pretty good at 28-seconds. It is a highly distorted irregular with a small companion close at hand. Streams of matter have obviously been pulled off the main galaxy by close encounters in this crowded field.

NGC 1241 (Arp 304) is a very pretty magnitude 13 spiral that shows a lot of detail. Why is it here? It's been messed with by the small nearby galaxy, NGC 1242. The arms are obviously misshapen from its encounter.

IC 1892 (Arp 332). IC 1892 is an attractive galaxy with an odd looking hooked arm, but that is not why it is part of an Arp. It's a member of Arp 332, which is the chain of galaxies that leads off to the northwest. Galaxy chains were another oddity that caught Dr. Arp's eye.

NGC 1097 (Arp 22) is one of my all time favorites, which I knew well from The Herschel Project. Even under less than optimum conditions, it's easy to see the effects in its arms and center caused by interaction with the companion.

NGC 1888 (Arp 123). This Arp is of Mr. Chip's "E-like galaxies perturbing spirals." 1888 is the spiral, while the little companion E is NGC 1889.

NGC 1875 (Arp 327). This is another galaxy chain consisting of a prominent (magnitude 14.6) elliptical and three little sprites. The whole shebang is also known as Hickson 34.

NGC 1232 (Arp 41) is a beautiful near-face-on magnitude 13.9 galaxy in Eridanus. The small companion, LEDA 816443, which is a barred spiral, may be interacting with the main galaxy.

NGC 1347 (Arp 39). This is in Arp's class, "spirals with low surface brightness companions on arms." Not much detail in the main galaxy, but this magnitude 13.9/16.2 duo makes a pretty sight.

NGC 2276 (Arp 25) is a nice spiral, if one with a weird shape, paired with a bright elliptical. It is in Arp's "one heavy arm" class, and on the original video I can see one arm is indeed pulled off in the direction of the elliptical (NGC 2300).

NGC 2300 (Arp 114) is a repeater. It is the elliptical in the field with Arp 25. It gets its own entry because it fits Arp’s class "ellipticals perturbing spirals."

NGC 2655 (Arp 225) lands in the class "amorphous spiral arms." Can I see signs of them? Maybe.

NGC 2633 (Arp 80) is a pretty little thing. Arp places this in the group "spirals with high surface brightness companions on arms," but it's not clear to me, even looking at the atlas' POSS plate, what he was talking about.

NGC 2523 (Arp 9) is in Arp's "split arms" group. In the original video, I can make out that at least one of the arms is divided in two lengthwise.

IC 356 (Arp 213) is nice, but the reason for its inclusion in the catalog is that "faint straight absorption lanes lead toward nucleus, become triple". It's impossible to see such features in my picture, and derned near it in Arp's POSS image in the atlas.

NGC 1961 (Arp 184) is of the "narrow filaments" class, and it's pretty easy to see a couple of relatively thin arms (?) in the video.

NGC 1569 (Arp 210) is in the group that features "irregularities, absorption, and resolution." By "resolution," I assume Dr. Arp was talking about the knots/star forming regions along the disk of this interesting M82 like galaxy.

NGC 2608 (Arp 12) is a member of the "split spiral arm" class, with it being fairly easy to see that at least one of arms is divided lengthwise in the video.

NGC 2623 (Arp 243) Arp puts this one in the class "appearance of fission," and it is indeed possible to see the central region appears almost divided.

NGC 2535 (Arp 82) is a strange and beautiful little thing. It's an Arp because it has a "high surface brightness companion on arms."  The companion is NGC 2536.

IC 2339 (Arp 247). This pair of small galaxies, which also includes IC 2338, is an Arp because of its "appearance of fission," to include a dim lane of material that seems to connect the two, but which is invisible in my image.

NGC 2672 (Arp 167). Supposedly this pair shows "diffuse counter-tails." But they are not only invisible in my image; I don't see them in the atlas’ image either. The smaller galaxy is NGC 2673.

NGC 2648 (Arp 89) is another member of the "high surface brightness companions on arms” group. The pretty and bright companion is MCG 2-22-6.

And so it went till about 10 p.m. Just as I was getting ready to head to the clubhouse to retrieve the second Monster of the evening, I noticed the sky background on my monitor had turned a sickly green. That means the camera is looking through considerable clouds/haze. Poked my head out from under the canopy and saw that, yeah, them suckers had come back. Gave it about an hour and a half, till a line of clouds appeared in the east and began to look positively threatening.

That was alright. Operation Arp was off the ground, 23 objects were in the bag, and I was feeling good. That good feeling was soon bolstered further by a shot of the blessed Yell and a Finding Bigfoot marathon on the cable TV. I also did a bit of strategizing about the NexRemote virtual port problem. I thought and I thought, but until I got out and tried it again and saw exactly what happened, it was hard to know how to proceed. I did know that if I couldn’t get it to work, I would not be able to use NexRemote for Operation Arp; I’d have to use the hardware hand control and connect it to SkyTools 3 with a non-virtual serial cable.

Saturday came with clouds, but mostly fluffy, drifting ones, not dark, threatening, stationary things. This would be the last full day of our Chiefland adventure, but there was still a lot to look forward to. In addition to a long night (I hoped) of deep sky work, this would be the day for our traditional visit to Duma Key (OK, OK, it’s really Cedar Key and does not involve haints and spooks).

Before lighting out for The Key, we had to make a last run on WallyWorld for AAs and AAAs for our red LED flashlights, which had got a fair amount of use Friday night. I noticed that while Wal-Mart’s benighted magazine rack did not have that greatest of all magazines, Sky and Telescope, it at least had Astronomy. Looked to be a purty good issue too (with a spiffed up format), but I figured my subscription copy would be waiting for me back at the Old Manse.

Cedar Key was great. The poor old Rusty Rim Bar and Grill, one of our former favorites, is still out of business and vacant, but we have plenty of other faves, like Steamers Clam Bar and Grill, which is where we wound up. Your Uncle chose the crab bisque, which is just crazy-good. I also ordered one of their to-die-for burgers, but that rich bisque dern near spoiled the massive assemblage of bacon and cheddar and beef for me. Oh, and of course I had a couple of cold brewskies to go with it. After lunch we hit one of the shops for Cedar Key t-shirts for the grandsons. Yes, hard as it may be to believe, Unk is now a grandpappy—twice over!

Saturday Night:  Herschel Heaven

I tried to take a nap back at the motel, but was unsuccessful. I was feeling a mite jittery because of the obviously unsettled weather and because of my need to troubleshoot NexRemote’s virtual port. I managed to stick to the room till five, but at the stroke of, I jumped back in the truck and made tracks for the field.

Despite my nervousness about Saturday evening, all went surprisingly smoothly. When it got dark, Bertha aligned without complaint and I was able to see what was what with the pea-picking virtual port. When I started NexRemote, I selected virtual com port Com 5 and immediately got a “not available” warning. Rut-roh. Me being me, I just dialed up Com 6. Not only did I not get a warning, the laptop emitted a “bing-bong” sound just like you get when you plug a USB - serial cable in.

That was only half the battle, though. The real problem, which reared its ugly little head not long after I started The Herschel Project, was that go-tos were lousy using the virtual port, and tracking soon went to hell. I brought up SkyTools 3, connected it to Com 6, clicked on M43 in the Messier list, and mashed “slew to.” Off we went to it. Centered. M1? Same. Tracking? No problem; everything remained rock solid in the field. And that’s the way it was for the rest of the night. Any Arp or anything else I clicked on in SkyTools appeared on my monitor and stayed there.

Why had I had trouble before? I was using a netbook when the virtual port hassles began. And I was using a no-name USB serial cable. I think I may also have been running an earlier version of NexRemote. Could have been any one of those things. The important thing is that the virtual port is now working and will make Operation Arp much easier.

And Arps, mostly non-NGC Arps, were just what I went after for a little while:

Arp 52 (PGC 17109). There’s not much to this little magnitude 15.5 fuzzie-wuzzie other than that it does have a "high surface brightness companion on arms," which I take to be the bright area near its center.

Arp 219 (MCG 0-10-9) is a cutie. It's an Arp because it fits in Mr. A's "adjacent loops" class. I was surprised to the see the loop on the south side fairly easily.

Arp 180 (MCG 1-13-34) is another member of Arp's "narrow filaments class." Can I see evidence of that? At first I don't think so, but one distorted arm is eventually visible in the video.

Arp 187 (MCG 2-13-40A) is also a member of the "narrow filaments" group. Can I see the feature? No way. This is a tiny 15th magnitude sprite.

NGC 2418 (Arp 165) is a "diffuse filaments” galaxy, and one of these is visible—barely.

When I’d finished recording (I do 30-second recordings of all objects) Arp 165, fetched a Monster, and spent a little time with various friends on the field, I noticed the sky was going south in a big way. Well, not really a big way, but there was increasing haze. I judged it not to be bad enough to shut down, but not good enough for more Arps. It looked clear enough to revisit some brighter Herschels, though.

Why am I redoing some of the Herschel objects I imaged with the Stellacam 2? It’s not that the pictures done with that black and white camera are bad, though they are noisier than those the Mallincam turns it. Mostly, it’s because many of the spring objects were imaged under poor conditions, especially the Leo – Coma – Virgo galaxies. Not only were some of ‘em shot under poor transparency, many of ‘em were too close to the horizon. With the pressure of the Herschel Project bearing on me, I would shoot a galaxy anytime it was in the clear, no matter how low.

It was just so nice to get back into that blessed Herschel groove. Find a likely candidate on SkyTools’ Herschel Project list, highlight it, click “slew to” on ST3, grab 30-seconds of video with the DVR, and on to the next. Just heaven, y’all, just heaven.

Until, like it had the previous night, the monitor’s background turned green. There’d already been a couple of cloudy interludes, so I decided to wait this one out. I waited. And I waited. Till I was sure that, while there was no threatening weather on the way, it wasn’t going to improve enough for more Herschels, much less Arps. But I’d done good, I thought. In addition to the Arps earlier in the evening, I had corralled fifty fracking Hershels. Not bad for an iffy night.

Back at the Day’s Inn, I wound down with something or other on the History Channel. No MeTV on the cable there, so I was deprived of my usual Saturday night fare, Svengoolie, who was showing Island of Lost Souls, dangit. Still, I was in a good mood even though I hadn’t got many Arps on this inaugural expedition, I thought. But a look at my logbook showed I had actually done plenty, 28. Which is probably about the right pace for Operation Arp, or maybe even on the high side. So, the final tally was 28 down 310 to go, y’all.

Next morning, we were sad, as we always are, to say aloha to Chiefland, but it would only be for a few months. The CAV and The Chiefland Observers are going strong; there were plenty of people on the field for a semi-cloudy January new Moon and everybody seemed to be having a great time. By the end, we had close to a dozen scopes onsite. What with me and Dorothy now resolved to stay in The Swamp after my retirement, I think we can look forward to many more CAV trips to come, which suits me just fine, muchachos, just fine.

And that’s the way it is, you-all, from good old Chaos Manor South out on the edge of The Great Possum Swamp. Oh, if you'd like to see more pictures from our trip, see Unk's Facebook page. Not a friend? Just ask.

Next Time:  The Polar Alignment Party…

Saturday, January 12, 2013


Down Chiefland Way (Yet Again)

As you have learned from bitter experience, muchachos, when you see words like those in the title this morning, it means you will have to wait till next week for more of your favorite blog. Yep, Unk and Miss D. were on the road again to their favorite Florida destination, the dark skies of the Chiefland Astronomy Village. Their mission? Put a few final touches on The Herschel Project and begin a new observing program. What new observing program? All shall be revealed next week, but till then here are a few pix from another great trip…

Next Time: Operation Arp...

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