Galaxies revealing detail/spiral structure

I am curious what people would list as galaxies that reveal the most spiral structure/detail in a moderate aperture dob, 12.5-16". Of course comments from users with smaller or larger scopes are welcome as well.
Joe

In my 15" Discovery dob, M51 is one of the finest. At a dark sky location I can easily see spiral arms as well as the connecting "bridge."
David Vaughn

In addition to those mentioned I can get hints of spiral arms in M81 with my 8". So I would assume that quite a lot more would show up in a 12 to 15. I can also get a fine dark lane in the Sombrero (M104). Others have mentioned M74 as a good face on galaxy (but that a faint fuzzy in my 8").

Hi Joseph,

NGC 1365 shows great spiral arms in a 10" and a 10" will also start to show the spiral arms of M83.

Cheers,

Maurice

Like most observers I find M51 to be the galaxy where the spiral structure is most easily seen. I use a 12.5-inch Portaball and prefer to use a magnification in the 120 - 200x range when looking for detail in galaxies. Exceptions are M31, M33 and M101 where I use lower power. My personal favourite is M101. Under dark and clear skies this galaxy displays an elegant spiral pattern with bright patches in the arms. Other possible candiates which I have not yet had the possibility to check out (got the 12.5-inch this spring, and since then weather has been lousy) are M99, M100 and M61 in the Virgo cluster. The sprial arms of M81 can be glimpsed, but they are difficult.
I also recommend the M82 class of galaxies - edge-on systems with obscuring clouds. NGC3556 (near the owl nebula) is a good example. There is also one or two good ones in Sculptor - too far south for me. Finally, the dark "eye" of M64 is something to look for. I don't find it really easy, but with sufficient magnification it can be seen in the 12.5-inch.

Did anyone mention NGC 2403 in Camelopardalis?

NGC 7479 in Pegasus may exhibit some spiral structure at that range of apertures.

Dave Mitsky

Structure in Galaxies

I’ve been working on a list on this very issue since the fall. I put it together as a “To See” list with ideas from various sources as to potential visible structure in galaxies (SAC's great M and NGC downloads; ideas from members of the Cloudy Nights and Astromart Deep Sky chat groups, etc.).

Obviously, as pointed out in this thread, ability to see structure depends on seeing and equipment, so I’ve been using a simple observing rating system to reflect differing access to sites and scopes:

I: mid-size scope (8-11) in good suburban conditions (most little dipper stars, milky way at least barely vis)
II: big aperture (12.5 plus) in good suburb skies (I believe aperture helps in mod light pollution)
III: mid-size in dark skies
IV: big aperture in dark skies

Though it was also pointed out here that “dark skies” are not always sufficient, there’s seeing and transparency. And this system is redundant (any structure seen at condition I, would be at seen at I+, but I am keeping a log and sometimes observe the galaxy first through a friend’s big scope at dark skies then try it at home in my 9.25. (I like to press the backyard limits of the hobby.) In the list below observing status (I-IV) is assigned only where I’ve actually observed the galaxy. Most of my III’s are a single night at Devils Garden Campground in Arches national park, UT, a remarkably dark place.

Messier:
M31: dark lane at II, 2 lanes at IV
M33: spiral at IV
M51: spiral at I, II and III; bridge to companion and structure within arms at IV
M64: blackeye maybe at III, definite at IV
M74: spiral
M82: dark band/constriction at I, irregularities at II and III
M83: spiral
M95: spiral
M96: spiral
M99: arm at IV
M100: spiral
M101: spiral
M104: dust lane, asymmetry at II, III and IV
M108: mottling

NGC:
253: various structure
772: arms, tail
891: dust lane at III and IV
1365: spiral
2403: spiral
2903: Leo: a nice surprise: Bar visible, with bright halo at III.
2911: dust lane at IV
3079 UMa: Edge on with asymmetric wings, and mottled texture (III).
3184 UMa: Large oblique edge-on with a dark lane in and out of visibility (III).
3227: pair at III and IV
3556: edge one, dust lane
3628: dust lane, asymmetry
4038/39 Cor (Interacting “Antenae” galaxies): Too bad on this neat object: Just too faint for antenna structure, only a hint of two lobes (at III, but lower in sky).
4274 CVn: No spiral structure visible; nucleus and elongate halo (III).
4449 CVn: complex structure, seems like two nuclei; noticeable curled-up east end (III and IV)
4559: spiral arms
4565 Coma: this was a downer: even in the best dark skies the 9.25 cannot seem to resolve the dark band in this famous edge-on very well, averted imagination helped, but dust lane not consistent at III. Easy dark lane at IV.
4567: linked pair
4535 Vir: large, textured object but no further structure visible (III)
4567/68 Vir: two lobes of linked pair visible, with nuclei in each (III)
4631: dark lane
4656: hockey stick visible at III and IV
4725: bar
4752: dark lane
4754/62 Vir: 54 shows large nucleus, but that’s it; 62 is striking edge on, no dust lane visible, but obvious central bulge (III)
5128: dark lane
5746 Vir: nice edge on, dust band not visible (III)
6207 Her: bright nucleus, not other vis structure (III)
4490/85 CVn: S shaped spiral visible (2 extended arms); w/ small companion (no link) at III.
6207: mottled with bright nucleus
7331: spiral structure and dark banding
7479: spiral

Other Interesting Galaxies to see:

Other edge-on's like NGC 55, 253; 891, 2683, 3115

Odd shaped galaxies like 2549 ("Bear Claw"), 275, 1097, 4490, and other Arp galaxies

Galaxy clusters/groups such as Abell 779/NGC 2832, Hickson 44/NGC 3185, "The Box"/NGC 4169; the face in Markarian’s Chain (great at III).

Any additions or amendations appreciated!


Bill Travis