M31 (NGC 224), Andromeda Galaxy, spiral galaxy, Andromeda
Just about visible to the naked eye (after a few minutes of dark adaptation) from my garden, though obviously this gets easier when it’s overhead on a dark night. With averted vision you start to get a sense of its large size and oval shape. Unmistakable in binoculars and small scopes, but detail elusive other than a star-like core.
50x: In the XT10 M31 shows a very bright core with a condensed, stellar nucleus. Too big for the fov even in the Panoptic. Lots of field stars superimposed over the galaxy; dark cut-off from dust lane clearly seen on north-western side (towards M110). When it’s nearer the zenith I can start to see the galaxy extending beyond the dark dust lanes. The star cloud NGC 206 seems to be visible with averted vision as a subtle brightening.
92x and 133x: Higher magnification doesn’t really change things other than making it harder to find my way around. M31 can appear frustratingly bland to the untrained eye. Aside from the two dust lanes, the galaxy fades so smoothly into the background, it’s hard to tell where it ends. The globular cluster G1 (Mayall II) should be visible in my scope, but I haven’t yet managed to track it down.
M32 (NGC 221), dwarf elliptical galaxy, Andromeda
Shows up very well in the TV60 and the SP-102 at magnifications around 40x (appears stellar at low powers), along with the fainter M110.
92x: Small, bright elliptical galaxy south of M31’s core. Occupies the same field of view as M31 in the Ethos. At 133x it shows a star-like core.
M33 (NGC 598), Triangulum Galaxy, spiral galaxy, Triangulum
Oddly enough, I always found this galaxy easier to see in 7x50 binoculars than in the 4-inch scope. On a really good night the binoculars even show a hint of the backwards “S” spiral shape.
XT10: Faintly visible in the 9x50 finder (which saves time sweeping for it). At 50x M33 is obvious as a large circular blur with a distinct, star-like condensation at the nucleus. At 133x the huge star-forming region NGC 604 is immediately noticeable as a small but obviously non-stellar patch of nebulosity adjacent to an 11th magnitude star. (It’s visible at 50x too, though it’s easily overlooked at this lower magnification. Certainly much easier to pick out than the NGC 206 star-cloud in Andromeda.) Every time I see it, I find it almost mind-boggling to realise that I’m looking at a nebula in another galaxy.
NGC 604 is also useful as a reference point for tracing out M33’s spiral arms. The northern spiral arm is easier to see than the southern one, appearing as a clumpy patch of light curling from the core towards a bright field star. The nucleus remains star-like, with a faint star close to it (in line with NGC 604). A few of the other HII regions are suspected with averted vision, but not to the point where I could say I was confident of detecting them.
92x: Could almost describe M33 as “bright” in the Ethos, particularly the core region. NGC 604 still obvious at 92x. Spiral arms seem mottled with averted vision. Suggestion of dark patches immediately south and southeast of the nucleus.
M34 (NGC 1039), open cluster, Perseus
92x: Array of bright stars surrounded by a loose hexagon of stars, like a large spider sitting in a web. Two close stars of equal brightness form the spider’s “eyes”.
133x: Large, bright and loose – more impressive than M39 in Cygnus, but this cluster does look better in a smaller wide-field scope.
M35 (NGC 2168), open cluster, Gemini
50x, 92x and 133x: Rich, large cluster, with a chain of similarly bright stars forming a very distinctive arc across its face. Nearby cluster NGC 2158 is visible to the southwest as a condensed patch of light – starts to resolve (with averted vision) at 133x, but not as easily as NGC 1907 in Auriga.
M36 (NGC 1960), open cluster, Auriga
50x, 92x and 133x. Smaller cluster than M37; individual member stars brighter but less numerous and arranged in pairs. Would be more highly regarded if it wasn’t outshone by its neighbours.
See also:
NGC 1931 (“The Fly”), emission nebula, Auriga
Little smear of light one degree west of M36. Higher magnification reveals a tight triangle of stars at the centre. Quite bright for a non-Messier nebula.
M37 (NGC 2099), open cluster, Auriga
50x: Lovely rich cluster, roughly triangular – instantly recognisable. Dark rifts and chains of stars give it a symmetrical shape reminiscent of a crab or beetle (very much like O’Meara’s sketch in The Messier Objects).
92x: Superbly rich in stars – best of the three Auriga Messier clusters, and arguably the best winter cluster (if you regard the Double Cluster as an autumn object). Prominent orange-red star at centre.
M38 (NGC 1912), open cluster, Auriga
50x, 92x, 133x: Large, rich cluster; somewhat “straggly” compared to M37.
NGC 1907 is in the same field of view at 50x, half a degree southwest. Appears as a small, condensed cluster – some resolution with averted vision at this magnification, giving it a “sparkling” appearance. Partially resolved at 92x and more so at 133x.
M39 (NGC 7092), open cluster, Cygnus
50x: A sparse cluster of bright stars, spilling outside the edge of the field of view even at 50x. Too loose and large for a big reflector; looks better in binoculars or a small wide-field scope.
92x: Shows well in the finder as a triangular concentration of stars. At 92x it becomes a loose collection of about two dozen bright blue-white stars barely fitting in the Ethos field of view, plus a scattering of fainter ones blending into the rich Milky Way background.
M40, Winnecke 4, double star, Ursa Major
171x: An uninteresting pair of 9th magnitude stars – what more is there to say about it? Messier (following up on an observation by Hevelius) knew it wasn’t a nebula, but included it in his catalogue anyway – and so must the rest of us if we’re serious about completing The List. Fortunately M40 is en route (from Delta Ursa Majoris) to a much more worthy object…
NGC 4605, galaxy, Ursa Major
171x: Faint, extended galaxy aligned roughly east-west. Shows a brighter bar-like core region which seems to be at a slight angle to the rest of the galaxy. An intriguing object, made more interesting by the knowledge that it’s less than a degree away from the famous Hubble Deep Field.
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