Sunday, October 23, 2016


Issue #514: How Hard are the Messiers from the Backyard (Part II)?

M110 (lower right)
As I was scrambling around making preparations for the trip to our big fall star party, the Deep South Star Regional Gaze, I took a break and put together the conclusion of last week’s article, an executive summary of the Messiers. Just how difficult are they from the average compromised (but not too horrible) suburban backyard?


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!


Have fun at the Deep South Star Gaze. Right now, it looks like you should have some nice views/images to write about if the weather holds. Up here in NW Pennsylvania, the nasty lake effect cloud season is starting, your prime season begins, ours ends. We had a great summer, may your prime observing season bring the same.

John O'Hara
Oil City, PA
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