Sunday, October 30, 2016
Issue #515: In the Dark with a 4-inch Refractor
And so, my fall star party season reaches its apex this year with the vaunted Deep South Star Gaze (née the Deep South Regional Star Gaze). Usually, when I am on the road whether to an observing event or to speak to a club somewheres, you get no blog. This week was different; I found myself with a short article all ready to go. Practically wrote itself, maybe because the below things have been much on my mind of late.
In recent times, I've developed a new appreciation for what a small and inexpensive and simple telescope can do. That comes after spending plenty of years thinking you can't have fun without a big gun and a ton of electronics. One thing that's turned me aside from the big and complex is that after suffering last summer's back problems, I spent months where I didn't dare even haul a C8 into the backyard. That was coupled with my increasing turn to refractors, and, over the last couple of years, a desire to simplify, simplify, simplify.
During those past (almost) two years, I’ve come to want to not just reduce telescope headcount as described in the above piece, but to, yes, simplify as much as is practically possible the scopes I still own and use. While I will still haul quite a lot of astro-junk to a star party, it's not the ton of astro-junk of the last couple of decades, as you’ll find next week when you get a report on the 2016 DSSG. Honestly, I just don't have much patience for All That Stuff in this latter age.
There is a limit, though. While you can have tremendous fun with binoculars or a 60mm telescope once in a while, and while instruments in that class are all some of you ever use, I, like most of y’all, want to see a bit more than what the really humble instruments can deliver. I’ve long thought 4-inches of aperture is the practical lower limit for most of us most of the time. Even so, what the heck can you possibly see with, say, a fast 4-inch achromatic refractor on a cheap alt-azimuth mount? I found out at the Possum Swamp Astronomical Society’s (semi) dark site this past Saturday...
It looked like it was going to be a beautiful night, if a little cool as I judge such things lately, and I certainly wanted to get out there and observe. Frankly, however, the idea of loading up a tripod and a GEM mount and batteries and a big OTA and maybe a computer left me feeling slightly depressed. Still, I wanted to be at the site with my club buddies. So, what if...what if...I just packed the Explore Scientific AR102, a short 4-inch refractor, and my good old SkyWatcher AZ-4 alt-azimuth mount?
Sure, I probably wouldn't see much with that kind of rig—everybody knows you need at least 10-inches of aperture to see anything of the deep sky, right? —but I could bum looks through the scopes of my mates, and if I got tired of that I could just go home and watch TV.
One thing that encouraged me to head to the site even though I wasn’t in the mood for a pedal-to-the-metal observing run? I am now OK with going out there on iffy nights or nights when I might not want to spend more than two or three hours on the field (at most). Compared to the old days, when I lived at the legendary Chaos Manor South, the dark site is now just a hop, skip, and a jump away, a mere 30-minutes to the west.
Loading sure was sweet. 10-minutes—if that—to plop the 102 in the backseat and the AZ-4 in the cargo area of the 4-runner along with an eyepiece box. Out on the observing field setting up was similarly pleasant. No connecting anything, no alignments. The only concession I made to modern technology was that I brought along my Android tablet running SkySafari Pro for charts. I could actually have been just as happy with my current fave print star atlas, Sky & Telescope's Pocket Sky Atlas Jumbo Edition. It was all simple and easy, yeah, but I was still skeptical I'd see much with such a minimalist rig.
In addition to scope and eyepieces, I did bring along my big Plano tackle box, which holds flashlights, filters, and the other gimcracks I use frequently, but I didn’t bother with the DewBuster dew heater system. The air was surprisingly dry, and I figured my 12-vdc window defroster would suffice if any dew accumulated on the objective lens. Naturally, I had to bring along a jump-start battery pack to run the zapper gun, but I hoped it could remain in the 4Runner.
Once it (finally) got dark, it was time to see what this somewhat silly little scope could do, starting with globular star clusters. Surprise! M13 was beautiful and nicely resolved at high power. So was M2. So was M92. After those three showpieces, I did a quick tour of the Sagittarius and Ophiuchus (Messier) globs, nailing each and every one. Some were just fuzzballs, sure, but some would have remained fuzzballs even in an 8-inch, and all nevertheless looked good.
What really looked good Saturday night? The Lagoon and Trifid nebulae in one low power field using my el cheapo Zhumell 16mm 100-degree eyepiece, the Happy Hand Grenade. After that, I just spent some time cruising up and down the "teapot steam," the Sagittarius Milky Way, bouncing from one open cluster to the next. I didn’t obsess with ticking objects off a list, just relaxed and looked. I observed many other objects over the course of the relatively short night, but the trip was more than worth it just for the opportunity to drink in the wonders of Sagittarius in a wide-field telescope.
How about the dreaded chromatic aberration? I'll be the first to admit my eyes are not as blue sensitive as they once were, and for that reason the color purple was not very evident. Well, except on Venus. But who spends much time on Venus? Even Vega was not bad. Sure, there was come chromatic aberration haze around the star, but it wasn't like a kaleidoscope. On normal deep sky fields, you wouldn't have known the scope was a fast achromat. The stars were nice and tiny and sharp. I did have a look at Saturn, and the view, given the short focal length of the telescope and the resulting need to use a very short focal length eyepiece to get a good look at the planet, was rather impressive. Despite the low altitude of Saturn, Cassini's Division was nice and sharp.
I am currently focused on revisiting the Messiers, but did do a few NGCs too. The Helix Nebula, for example, which was quite impressive with a UHC filter. As far as the more challenging Ms (for a 4-inch), M72 was just a smudge, but there. M56 was not blindingly bright, but actually showed a little resolution.
No matter how nice a telescope is, it won't perform well without a decent mount. The AZ-4 is not a fancy custom alt-azimuth mounting like the excellent (and expensive) Half-Hitch mounts, for example. It's not finely machined, and there are no slow motion controls. There are adjustable tensioners/locks for both axes, a Vixen compatible saddle, an OK (extruded aluminum) tripod, and a nice big pan-handle. It's motions are smooth, very smooth, like the motions of a well-made Dobsonian, and I had no problem tracking objects at higher powers. When using a relatively short refractor, I do unscrew that big pan-handle, as it just gets in the way with anything shorter than, say, a 4-inch f/10.
While the SkyWatcher AZ-4 doesn't appear to be currently available in the U.S., you can get the exact same mount badged as the Orion Versago II for a somewhat higher price. The SkyWatcher mount was not only slightly less expensive than the Orion version, the AZ-4 came with a rather nice 80mm f/11 refractor. I have used this mounting with a C8 and it's usable with that much scope for casual viewing, at least. With the AR102, it's pretty perfect. Recommended.
And so it went for a few hours. Remarkably, I never tired of the 4-inch, and had no need to cadge looks through my fellow observers' telescopes. The only scope I used other than my own, really, was a friend’s StarBlast, which, being a 4-inch f/4, was more like my instrument than different, even though it was a Newtonian reflector. The ‘Blast delivered outstanding images, and it was clear there would be a tremendous amount of things to be seen with the little green guy. Seems to me that in addition to being increasingly enamored of easy to manage telescopes, I am also increasingly fond of wide-field views. Maybe that’s a consequence of having spent several years concentrating on very small slices of the sky when I was doing the Herschel Project.
Finally, the true beauty of astronomy with an ultra-portable 4-inch rig? Packing for the journey home. Again, 10-minutes, perhaps, and I was ready to roll, and a goodly part of that 10-minutes was consumed just by putting the caps back on my eyepieces. Driving off the field, I was honestly bowled over by the knowledge that not only could I see something with an ultra-simple, ultra-cheap telescope, but that I could see so much.
Sunday, October 23, 2016
Issue #514: How Hard are the Messiers from the Backyard (Part II)?
|M110 (lower right)|
You would think this sometimes-overlooked globular star cluster in Lyra would be easy. It’s a Messier and it is often riding high in the sky for mid-northern observers. Not so. It’s loose, and in a 4-inch is usually nothing more than a dim smudge. It was actually totally invisible in a 4-inch from old Chaos Manor South downtown. Even in the suburban-country transition zone, it needs a 10 – 12-inch to start looking good, though my 4-inch Explore Scientific AR102 will deliver at least a little resolution there.
No problem. This is the northern sky’s most famous and maybe best planetary nebula. A 3-inch will show its basic shape (although the central hole is not always easy).
If you are able to see this Virgo spiral from your backyard, count yourself lucky. I can’t glimpse it with a 4-inch, and in an 8-inch SCT it is just a dim elongated something that often requires averted vision.
M59 is a lot like M58: a small, off-round, dim galaxy. The saving grace is that it is in the same field as another galaxy, the more prominent M60, which makes for a pretty view.
This one is a little more interesting than the previous two, being bright enough to be doable with direct vision. A 10-inch scope will show some outer haze in addition the bright, oval core. On a particularly good night a 10 – 12-inch may also show M60’s companion galaxy, NGC 4647, which is a mere two and a half minutes away.
From the country, M61 can show spiral structure. From the city? You need an 8-inch to make it easy to see at all, and what you will see is a round fuzzy that may need averted vision.
When the summer sky conditions aren't too hazy, I can make out this Ophiuchus globular without much difficulty in a 4-inch. An 8-inch on a similar night may resolve a few stars, but that is not easy.
Canes Venatici’s Sunflower Galaxy is one of the gems of the Messier list. That said, in the city don’t expect to see much more than a bright (for a galaxy), large, elongated glow. The patchy spiral arms? For a good look I need my 10-inch, Zelda, at the club dark site.
Another showpiece, the Blackeye Galaxy is easy enough in a 3 – 4-inch telescope. The dust patch, the black eye? 8 – 10-inches and a darker observing site than my backyard is needed to make it obvious to me.
One of the famous triplet of galaxies, the Leo Trio. While it’s not easy to make out these galaxies’ features from my out-back, I can always tell M65 from M66 (M65 is more edge-on looking).
Quite a sight together with M65. As above, it’s easy to tell the two apart (the third member, NGC 3628, can be difficult to see at all from the backyard, even in the 10-inch, on poor nights).
M67, Cancer’s “other” open star cluster, is one of my favorites. While not overly bright at magnitude 6.9, it’s rather compact and easy enough in the 80mm APO refractor.
Hydra’s seldom visited M68 is really not much of a globular cluster. I often need an 8-inch to see it from the backyard, and there is not a trace of resolution.
This is one of the globular clusters located along the base of the Sagittarius teapot. It’s low much of the time even for me, and is difficult in a 4 or 6-inch telescope. In an 8-inch it is there, but is still utterly unresolved.
Also at the teapot’s bottom is M70. It’s more condensed than M69 and looks brighter, but is still unresolved in an 8-inch (I can see it with the 4-inch). Resolving a few stars takes the 10, and it usually needs to be under a darker sky.
Sagitta holds this very loose globular. While it is indeed a globular, it looks more like an open cluster, and in a 10-inch it resembles M11. In a smaller telescope, a 3 – 4-inch? Visible, but only as a misty patch in a star-rich field.
Compared to M2, M72 is most assuredly Aquarius’ “also ran” globular. Quite faint and unresolved in a 3 – 4-inch and sometimes impossible with small scopes from the backyard. It’s easier with 8 – 10-inch instruments, but still unresolved in most suburban skies.
This is nothing more than a little group of four stars (it may actually be a galactic cluster rather than just an asterism). They are on the dim side, and in a 3-inch can look nebulous, which is likely why Chuck Messier included them in his list.
The famous Pisces face-on galaxy, a.k.a. “the Phantom Galaxy.” There is a reason it’s called that: it is incredibly difficult from the light polluted suburbs. That said, I spotted it (barely) with my 8-inch f/5 Newtonian when I was doing the observing for my book The Urban Astronomer’s Guide. “Spot it,” mind you. Nothing more. On a superior night, it was a dim round something in a medium power wide-field eyepiece. Maybe the toughest M of them all.
Somewhat lost in space in the area between Sagittarius and Capricornus, M75 is usually doable with a 3 – 4-inch, and on an outstanding night an 8-inch may begin to resolve it.
The Little Dumbbell (planetary) Nebula has a reputation for being tough in small scopes. Nonsense. I could usually pick it up with my old ETX60; especially with an OIII filter on the eyepiece. A 10-inch begins to reveal some detail beyond the fact that this peanut shaped cloud, the remains of a dead star, is composed of two lobes.
This face-on Seyfert galaxy in Cetus is easy thanks to its bright core. On the other hand, a bright just-larger-than-a-star core and a relatively bright surrounding haze is all you’ll see whether with a 4-inch or a 12-inch. Looks a lot like a small, distant, unresolved globular.
A reflection nebula not far from the belt of Orion, M78 gave me fits from my downtown backyard, even with a 6-inch. Out in the suburbs, it’s easy with a 4-inch scope, being visible as a strong haze surrounding a double star.
Lepus’ globular star cluster, the only respectable globular star cluster of Winter, really isn’t much. It’s a small dim spot with my 3-inch APO, and requires a 10-inch or 12-inch to show a hint of resolution.
This Scorpius globular is easy to see. It’s small (so small it can resemble a star at low power) and bright and is not a challenge for my William Optic 3-inch APO, Veronica Lodge. Resolution is harder, requiring the 10-inch Dobsonian, Zelda, and a lot of magnification.
Another Messier showpiece. Bode’s galaxy is frankly, however, only a showpiece for backyard telescopes because M82 is in the same low power field. While M81 is always visible from my backyard, it is only visible as an elongated bright oval. Seeing the gossamer spiral arms takes a dark, dark site and 10-inches of aperture (at least) for me.
M82 is a true showpiece. The Cigar Galaxy is not just visible in a backyard 4-inch, it shows off some of the dark detail in its disturbed disk.
The Southern Pinwheel Galaxy is relatively large and nearly face on, and that usually spells “tough.” It is always at least detectable, though, as a misty, round patch with a bright core with the 10-inch. To see it with a 4-inch was a definite challenge requiring dry, clear skies and the galaxy being near culmination.
M84 was usually visible in a 4-inch on a good night, but I liked to use a 12-inch Dobsonian, my now gone Big Bertha, to get a good look at the many other galaxies in the field. This area is one of the ends of Markarian’s Chain (of galaxies). M84 is paired with M86 in this field and is the brighter and rounder of the two.
In a 3-inch, this Coma galaxy can be a toughie, a dim, small, round spot. Much better in an 8-inch, where it shows off a bright, condensed core.
I love M86, which, together with M84, NGC 4387 and 4388, forms a little 1970s smiley face. As noted above, M84 is the rounder and brighter of the two Messiers.
Located in the heart of downtown Virgo, M87 can be detectable in a 3 – 4-inch on a good night and easy with a 10 – 12-inch. There is not much to be seen of this monster elliptical galaxy, though; just a bright center and some surrounding haze.
At the other end of Markarian’s Chain from M84/86 we find M88. It is doable in a 3 – 4-inch on a superior evening as a round fuzzball, and in an 8-inch begins to show off elongation.
I’ve seen this Virgo galaxy with my 4-inch C102 refractor, but it is an easier task for a C8. In my 10-inch Dobbie, it shows a brighter center.
|M84 and M86|
Near to M89, M90 is similar as far as visibility. In an 8-inch SCT or my 5-inch APO refractor it is clearly elongated.
M91 in Coma can be seen with a 4-inch using averted vision. Frankly, it’s not much better in a 10-inch. Even if you have a 20-inch under dark skies, you shouldn’t expect to see the galaxy’s spiral detail.
While this Hercules glob can’t hold a candle to M13, it is still great. Easy with my C102, Betty, where it even shows some resolution.
This is a rich Puppis open cluster, and on a good night a 4-inch will show upwards of 50 stars here with a medium power eyepiece. Looked superb even from my old downtown site with my Edmund Scientific Palomar Junior 4-inch.
On those punk nights when the haze is bad and the light pollution at its worst, but you still want to see a galaxy, M94 is where you go. Even in a 3-inch, it’s visible under remarkably poor conditions as a bloated "star" surrounded by faint haze.
While not as easy as nearby M105, I was often able to see Leo’s M95 with a 4-inch using averted vision. Of course, all it was was a dim, round spot.
I couldn’t see any details in M96 with a 3 – 4-inch, but it was at least easier to make out than its companion galaxy, M95. The C8 would show a little elongation at times.
Even moreso than M76, this one, the Owl nebula, has a reputation for toughness. Uh-uh. I could, as with the Li’l Dumbbell, see the Owl with my old and now gone 60mm ETX refractor (with an OIII filter). The dark patches? The eyes? That takes 10 or 12-inches of glass and a darker sky than what my backyard usually offers.
This Coma galaxy was often not easy. Not even with the 8-inch, where it sometimes required averted vision to show up at all. Obviously strongly elongated in 8-inch and larger scopes.
M99 was easily as tough as M98. It’s a low surface brightness, near face-on galaxy. Think “at least 8-inches.” In a C8, it is somewhat elongated on good nights.
Another Coma galaxy that frequently demanded the 8-inch. Even then, it was most often just a dim, round smudge.
Let’s go even tougher. The Catherine Wheel Galaxy in Ursa Major, another face-on, a large face-on, is nearly as difficult as M74. Nevertheless, I could sometimes see it with my 8-inch f/5 Newt, and could just about always snag it with my C11 as a large, faint glow.
Don’t worry about it. There ain’t no “M102.” It is most likely a re-observation of M101. If that makes you feel uneasy, look at NGC 5866, which has sometimes been claimed to be M102. NGC 5866 is doable in a 4-inch and obviously elongated in an 8.
This small, loose open cluster is visible in my C102, but occasionally melts into the background star field.
The famous Sombrero Galaxy. I could make out its equatorial dust lane (maybe with a little averted imagination) with my Palomar Junior 4-inch Newtonian on the very best nights in the city. The first time you see it, your reaction will probably be “Darn, smaller than I thought it would be,” so don't be afraid to pump up the power.
Was always cool in my Short Tube 80 and my Palomar Junior. It’s a bright, round Leo elliptical that really stands out. The small scopes would also sometimes turn up at least one of the two nearby NGC companion galaxies.
This Canes Venatici galaxy is nice in a 4-inch, but do yourself a favor and view it with a 10 or 12 (at least) where it will begin to show spiral detail in addition to a bright nucleus and a strongly elongated disk.
A seldom-visited Ophiuchus globular, M107 was routinely visible in my 6-inch home-built Newtonian 25 years ago. But only as a dim, round fuzzy. A 10-inch instrument is really mandatory to show a little resolution around its edges.
This galaxy, near M97, is not overly difficult and not overly easy. It can be seen in a 4-inch on better evenings, but an 8-inch makes it easier (and e’en then it may need averted vision). In a 10-inch on a transparent night, it will begin to show mottled detail.
Located near Phad in Ursa Major, M109 is a little easier than M108, but still just a dim oval in smaller scopes. 10-inch and larger instruments may show some details, mottling and dark lanes, in the disk on especially good spring nights.
And so we come to the end with M110, M31’s second most prominent satellite galaxy (after M32, natch). While it can be extremely easy in binoculars at dark sites, it can be quite tough with 3 – 4-inch telescopes from the backyard. Relatively large, it’s just a dim something until you get to 10-inches, where it begins to show elongation and a brighter center. Sometimes it even hints at subtle dark detail.
Whew! And there they are! Now, get out and see some of them while the good weather lasts. Down here, I’m pretty sure we are just getting a short reprieve and those cursed equinoctical gales are sure to be on their way!
Sunday, October 16, 2016
Issue #513: How Hard are the Messiers from the Backyard?
The Crab Nebula is at least detectable in a 4-inch telescope as a dim oval on good evenings. However, you will need a 12-inch range scope to begin to see much beyond that. In my 12-inch Dobsonian, Old Betsy, it would show its basic zig-zag shape without much fuss on a nice night. More than that visually, like the tendrils of gas that give it its name? That demands at least 12-inches of aperture, an OIII filter, and a dark site.
A 3-inch will show it, a 4-inch will deliver a little resolution, and an 8-inch will make this big thing begin to look nice indeed.
Similar to M2, if a little more difficult to resolve. Looks nice if mostly unresolved in my 80mm APO.
M4, the Cat’s Eye Cluster, is loose and a little dim. You can pick it up with a 4-inch, but don’t expect it to look like much.
My 80mm APO, Veronica Lodge, will show some stars at high power, and a C8 makes it into a semi-spectacle from less than perfect backyards.
At 25’ across, this cluster is big, but not too big and was just perfect for my old 4-inch StarBlast reflector, Yoda.
If the StarBlast richest-field-telescope did a nice job on M6, its wide field was required for M7, which is 80’ across. As a matter of fact, I much preferred my 70mm Burgess binoculars.
I can always see the Lagoon Nebula from out-back with a 4-inch, but it does not look like much. Just a little fuzz around a star. 8-inches of aperture and a UHC filter definitely help.
M9 is difficult, sometimes to the point of impossibility, with the 3 or 4-inch scopes. Mainly because of its low altitude. An 8 or 10-inch is a really good idea for this one.
Visible if unresolved in a 4 or 6-inch scope. My10-inch Dobsonian, Zelda, does a fine job on this rich and pretty globular star cluster.
The beautiful Wild Duck Cluster, one of the very best galactic clusters in the sky. Great in all instruments large and small. In binoculars or an RFT at low power, it resembles a loose globular. In telescopes of larger aperture and longer focal length it is an amazing flight of fowl.
The beautiful Wild Duck Cluster, one of the very best galactic clusters in the sky. Great in all instruments large and small. In binoculars or an RFT at low power, it resembles a loose globular. In telescopes of larger aperture and longer focal length it is an amazing flight of fowl.
Really needs a 6-inch even just to easily see this looser glob. A 10-inch can make something of it even on hazy backyard evenings.
My 80mm APO will show a few stars at high power, but just like the old observing guides say, a 6-inch is needed for much resolution. From the more light polluted suburbs anyhow.
Like M9, this glob is rather low for many of us and an 8 or 10-inch telescope is the way to fly if possible.
The Horse’s Nose Cluster was very pretty in a 3-inch refractor or 4-inch reflector, but this globular is unresolved in the small instruments. Better in a C8 or my 6-inch refractor, Big Ethel, but doesn’t begin to be great till you get to 10-12-inches.
If you just want the open cluster, a 3 or 4-inch will do it. Heck, 50mm binoculars will do it. If you want the Eagle Nebula you need an OIII filter, a 10 or 12-inch scope, and a dark hood to block ambient light from your eyes.
The Swan is easier than the Eagle, but from the backyard 8-inches of aperture is a help, and a UHC filter is a Good Thing.
This smallish open cluster is quite nice in my 80mm APO.
Somewhat tough southern glob. Low and large. Save yourself some frustration and apply 8-inches of aperture.
I can usually pick up the Trifid with the 80mm (equipped with a UHC filter), but it doesn’t look very good from compromised skies even with 12-inches.
Large and bright, this open cluster is not a challenge for a small telescope or binoculars.
I used to enjoy looking at this big globular with my old Short Tube 80 refractor, Woodstock, who didn’t have much trouble resolving a few stars in it.
Another bright open cluster that is nice in binoculars large and small.
This open cluster is small, about 5’ across, but rather dim with a given magnitude around 11. Nevertheless, I can sometimes see it with a 4-inch—if with difficulty. Nice in the 10-inch.
At almost half a degree in diameter, this open cluster is good in binoculars and excellent in an RFT like the StarBlast.
A magnitude 9 open cluster, M26 can be difficult in a 4-inch, looking much like a distant, unresolved globular. It’s not that much better in a 10-inch, which at best resolves a handful of stars.
The Dumbbell was sweet in my Short Tube 80, and really, really sweet in the filtered 10-inch, which shows the apple core shape most convincingly from suburbia.
This glob near the Sagittarius Teapot’s lid is visible in a 4-inch with fair ease, but difficult to resolve even with a C11 in the suburbs.
A small, dipper-shaped open cluster in Cygnus, M29 is good with a 3-inch, and a 10-inch or larger scope really doesn’t show much more.
A 6-inch is required to make M30 even look grainy, and a 10-inch is a must for appreciable resolution. I can usually spot it with a 3 – 4-inch, however.
I could often see the Andromeda Nebula (galaxy) naked eye even from my downtown backyard. Needs mucho field. The StarBlast was super fine for this monster.
M32, M31’s brightest satellite galaxy, is visible in the 4-inch, but sometimes dubious in binoculars.
Dimmer than M31 and still quite large. I've found the Triangulum Galaxy a pain with the StarBlast. The C8 reduced to f/6.3 and equipped with a 27mm Panoptic can always turn the galaxy up when it is riding high, however.
Bright but large. Perfect for the StarBlast or a similarly wide-field scope.
Nice in a 3-inch and just gets better with every increase in aperture.
Easy in the 3-inch Short Tube, and beautiful in a 10-inch.
Visible in the 4-inch, but needs the 10-inch Dobsonian to begin to show its incredible richness and its red central star well.
Very similar to M36. Very nice in the Short Tube 80 and in my 80mm f/11 SkyWatcher achromat.
This triangular open cluster is, like M29, good in an 80mm, and doesn’t get much better with larger telescopes.
A magnitude 10 range double star, it is very attractive in the 80mm f/11 refractor.
Another win for the StarBlast RFT. It’s bright and big and perfect for the little guy.
Looks great in any aperture, even from badly compromised backyards.
In the suburbs, it takes about 10-inches of aperture to show M43’s comma shape, but it is easy to at least detect in a 3-inch or a 4-inch as haze around the bright star Nu Orionis.
The Beehive. This huge open cluster in Cancer requires the StarBlast or a pair of binocs. Easy, natch.
The Pleiades are scrumptious in my 66mm APO, but I’ve never seen their Merope Nebula with that or any telescope from the suburbs—up to and including a 24-inch Dobsonian.
The open cluster is easy in a 3-inch, but the involved planetary nebula, NGC 2438, is invisible. Seeing that takes my 10-inch Dobsonian, Zelda, and an OIII filter.
Sparser but brighter than M46, M47 was rewarding enough in the Short Tube 80, but didn’t look truly nice till I applied the 6-inch refractor or an 8-inch reflector.
Like many Messier opens “bright and large.” An RFT is practically mandatory for good framing.
I could pick up this elliptical (S0) galaxy from the backyard with my 4-inch f/10 refractor or the 5-inch MCT without much hassle. Not a whole lot to see, of course.
This Monoceros open cluster is easy enough to see in a 3 – 4-inch. The main problem is finding it without goto.
The Whirlpool Galaxy is visible in suburban 4-6-inch telescopes as two dim fuzzballs, a larger one and a smaller one, from even under very poor skies. I've detected the pair from a spot less than a mile from a major shopping mall. To see more than that requires 10 - 12-inches and an especially good night.
This medium-sized, medium-bright open cluster is pretty in a 4-inch, and the entire area is impressive on a good night in an RFT.
To make spotting this glob easy, use at least 4-inches of aperture. 6 is better. And 8 is better still. It will take the 8-incher to achieve much resolution of the cluster’s stars.
To barely detect this less than impressive Sagittarius glob sometimes requires my 6-inch refractor. The 10-inch is mandatory if I want to see it at least look “grainy.”
This is an easier globular than M54 to resolve—if more difficult to find. I can achieve fairly impressive resolution with the 10-inch, and can often at least at least see it easily with the 4-inchers.
So…next time we wrap up this executive summary of the Messiers, and after that it’ll be time for me to get ready for my next big star party, the 2016 Deep South Regional Star Gaze. Fingers crossed, but for once it looks like the weather gods might be on my side!
Sunday, October 09, 2016
Issue #512: More Messier Madness!
|M87 shows off its jet to my Stellacam...|
What better time is there for chasing Ms? The nights are cooler now and their skies are clearer (you hope). Down here, I may only have to douse myself with one gallon of Deep Woods Off instead of two. And, oh! the Messier beauties you’ll find lurking now. The mid-late summer objects are still on display and lookin’ good. A glance to the east, though, will show the Autumn wonders are on the rise—look how high M15 has gotten—and if you’re up late you’ll begin to witness glories of Winter climbing as well.
Yes, fall’s a great time for a Messier hunt, for crossing them off your Life List. For this week’s edition, however, we’re taking the WABAC machine back to spring as we navigate through the countless faint fuzzies that comprise the great Coma-Virgo cloud of galaxies.
Yes, Coma – Virgo is wonderful, but what makes it wonderful? The sheer number of galaxies on display here and their pairings and groupings. When you stop to think about it, many, many are ellipticals without much detail to offer. Tons of ‘em are certainly easy enough to see with a medium size telescope in the backyard, however, including Messier 85, a magnitude 10.0, 7.6’ x 5.9 S0 elliptical galaxy. And you get a bonus galaxy to up the interest level; M85 is in the field with a dimmer companion, magnitude 11.6. 3.6’ x 3.5’ NGC 4394.
To find M85? While goto or DSCs are the way I’d go in these latter days, M85 is not too hard to pin down. It lies about 1.5-degrees outside to the northeast of a line drawn between two prominent stars, Diadem, Alpha Comae, and Leo’s Denebola. A magnitude 5 range double star, 11 Comae, is just a smidge over a degree to the west of the galaxy.
In the backyard, you’ll want at least an 8-incher to make this object easy on the less good nights. M85 is a galaxy that can be bright in small apertures on good evenings, but dim to the point of toughness on poorer ones. Above all, despite the fact that this is a lenticular with an oval, elongated shape, expect to see nothing more than the good old “round galaxy with a brighter center.” In other words, much like an unresolved globular star cluster. In order to see elongation in M85, I normally require 12-inches of aperture and a halfway decent dark(er) site.
How about the companion, NGC 4394? While it is small, it’s not tiny and is approaching magnitude 12. The 10-inch Dobsonian, Zelda, will show it on a nice night, albeit sometimes with difficulty. It is about 8.0’ northeast of the main galaxy. Medium high magnification can be a help here. In the backyard, what you can expect to see if you can see NGC 4394 is a relatively faint, round glow. From dark sites with larger apertures, this barred spiral galaxy begins to reveal its arms.
|The Face lookin' atcha...|
M86, an elliptical galaxy in nearby Virgo, as I mentioned in the last installment, together with its companion galaxy, M84, never fails to elicit a chuckle from me. This grouping is “The Face.” M84 and M86 form the eyes, a little elliptical galaxy, NGC 4387, is the nose, and a near edge-on galaxy, NGC 4406, is the mouth. At magnitude 9.8 and with a size of 10.0’ x 7.4’, M86 is quite prominent in 8-inch and larger scopes even from a relatively compromised backyard.
As I said in the last M-edition concerning M84, “There are so many bright galaxies within the arms of Virgo that it’s hard to know which one you are on. Luckily, the field here is pretty distinctive. If you simply must find 84 the old fashioned way, it lies halfway along a line drawn between Epsilon Virginis, Vendemiatrix, and Denebola, Beta Leonis. Positoned there, look for two bright fuzzballs about 17.0’ apart.” Which one is M86? It is the northeastern-most of the two brightest objects in the field. It is also more elongated than M84, being a Hubble Type E3.
As above, the cartoonish Face is the attraction here, that and the fact that this is the western terminus of Markarian’s chain, the mind-blowing line of galaxies stretching off to the east. But M86 itself? Sorry, pards; it is just another bright elliptical. Very noticeable but very featureless.
And so on to Virgo’s monstrous old fat-daddy spider of a galaxy, M87, for more of the same. This is one of those “been there” objects: there’s not much to see; all you can say is you’ve been there. Actually, there’s a little more to it than that. The knowledge that this is an awesome giant of a galaxy, a titantic elliptical with a mass of a trillion Sols, makes its sight thought provoking and even moving though there is no detail to be found.
The best way to get M87 in your eyepiece is to get on the distinctive M84/M86 pair first. Then, slew your scope a degree and a half southeast. Go slowly and examine the field carefully, but despite the galaxy crowded nature of this part of Virgo, M87 stands out well. In an 8-inch in the backyard it will be fairly hard to miss, and should be duck soup for 10s and 12s.
No, there’s not much to see of M87 other than a bright fuzzy ball. The field? Not too much here either for a small scope from the suburbs. There are two magnitude 12 range galaxies, NGCs 4476 and 4478, about 10.0’ to the northeast, but while they are small, they really need a 10-inch to bring them out of a bright sky background. In my C11 from the OK but not perfect skies of the old Georgia Sky View Star Party at Indian Springs State Park, M87 was…
Basically a diffuse round glow like a bright, unresolved globular cluster in a 3-inch telescope. With TeleVue Nagler Type 2 12mm, 233x I occasionally see hints of a condensed core, but it's mostly a featureless ball.
So that’s it? How about THE JET? M87 is possessed of a supermassive black hole at its core, and this is the source of an incredible jet of matter spewing out of the center of the galaxy. This jet is so huge and luminous that it can even be seen with amateur telescopes. Alas, those amateur telescopes need to be at least in the 20-inch range and stationed under dark skies. Ironically, my humble Stellacam II deep sky video camera in my C8 had no problem showing the jet with a 10-second exposure under suburban conditions.
M88…M88…which one is that? Oh, yeah, back over in Coma Berenices. It’s a bright enough Sb with an intermediate inclination to us that reminds me a lot of M63 (in photographs) with patchy spiral arms similar to those of the Sunflower Galaxy. At magnitude 10.1 and with a size of 6’54” x 3’42, it is not terribly challenging for a 4-inch when your backyard conditions are anything better than putrid.
The best way to land on M88 is to follow Markarian’s Chain, that great river of galaxies, from its beginning at M84 and M86 for about two degrees to the northeast to its conclusion. Luckily for us, M88 lies right at its northeastern end and is the most prominent galaxy in the immediate area. Take your time and move slowly; this is indeed the Realm of the Galaxies, and in a 10-inch or 12-inch, even from the suburbs, there are island universes all over the place. This is a rather star poor area, but there is a 7th magnitude sun half a degree to the northwest of the galaxy, which provides a good guide to M88.
When you are convinced you have M88, give it a nice long look, sure, but don’t expect too terribly much. Even larger apertures from good site only reveal that it is strongly elongated with a brighter center. The dusty spiral arms are really for the eye of a camera.
So you want to see M89, do you? Well, I salute you for charging through the fuzzy laden waters of Virgo. And this is not a bad one. It’s another round elliptical like many of the galaxies here, but is bright enough at magnitude 9.75 and small enough at 5’06” x 4’42” that it is a reasonably easy catch for your backyard 4-inch. If you can find it. Or, more properly, figure out exactly which fuzzball in the eyepiece is it.
Not sure exactly what to tell you if you have to star-hop. This object is just outside the heart of the Virgo cloud, and there are really no guide stars to help you on your way. If you’re star-hopping with a finder, the best way to go is to move your scope 1-degree northwest of M58, which is substantially easier to locate.
The best way to position the telescope on M89, though? The way I used to navigate Virgo-Coma in the days before computers: I’d galaxy hop. Using a 12mm Nagler eyepiece in my 12-inch telescope, I found it remarkably easy to move around the area by hopping from galaxy to galaxy with the widefield eyepiece and a (very) detailed computer chart. Back then, I used Megastar. Today, you’ll probably want to use SkyTools 3’s Interactive Atlas.
When you’ve arrived, you’ll find that while it is almost featureless, M89 is not entirely so. According to its specs, M89 is slightly oval, but in the eyepiece it looks entirely round. Otherwise it has a fainter halo and a brighter center. However, on an OK night with at least an 8-inch, you may see that it has an intensely bright, star-like nucleus, and that brings M89 into the realm of “very attractive.”
In images, M90, a magnitude 10.10, 9.5’ x 4.5’ spiral, is very pretty indeed, with a bright, oval central region and prominent dust lanes outlining tightly wrapped spiral arms. Unfortunately, once you get outside the central part of the galaxy, its surface brightness is low, and the arms are mostly for imagers, though they can be glimpsed with 10 – 12-inch telescopes on outstanding nights at outstanding sites.
Locating M90 is quite easy if you are already on M89. Just eyepiece hop, following a chain of 10th magnitude stars north for 40’ and you are there. An 8th magnitude star is 14.0’ southeast of the galaxy if you need more help, or just want to be sure you are on the correct galaxy.
When you are on M90, most of the time all you will find is the object’s strongly elongated middle part. And it may not be quite as bright looking as you expect given the galaxy’s fairly generous size. This is a galaxy to keep coming back to on superior evenings, however, since under the best conditions it can begin to give up respectable detail to medium sized instruments.
Oh, how wonderful M91 looks--in pictures. Even in fairly short exposures, this magnitude 10.9, 5.4’ x 4.6’ shows off a classically beautiful barred spiral shape with far-flung, open arms. In the eyepiece the story, as it often is, is somewhat different, but this is still a Messier, after all, and worthy of your attention for sure.
If you wanna get to M91, my advice (for the computer deprived) is to continue your eyepiece hopping, moving 1-degree 22’ west – northwest from M90. Take it easy, since this one definitely looks a little on the dim side. There is a magnitude 8.8 star just 17.0’ west of the galaxy.
I hate to be a bring-down, but even with fairly large telescopes under quite dark skies, about all you will see of M91 is an elongated something, and you may need averted vision to see even that much. On particulalry nice evenings, you may pick up a stellar nucleus. On the other hand, the camera loves M91, and even a 10-second exposure with my Stellacam 2 showed its basic shape:
As befits its status as M91, this is a marvelous galaxy, big, with a bright round core, a long bar, and easy to see, graceful arms that give it a classic barred spiral "S" shape.
And that, as they say, is that. Fun is fun, but done is done.
But we are not quite done with the Messiers here, though we are in the homestretch now, no denying it. How about your own observing program? If you haven’t caught ‘em all, resolve to do that over the coming year. I am hearing from quite a few of you who intend to do that very thing, and some who even say (my blushes) they are going to print out this series of blog entries and use them as their guide. That’s flattering, certainly, and though I don’t doubt there may be better guides to the M-objects than these articles, one thing is sure: the price is right!