M101 (NGC 5457), Pinwheel Galaxy, spiral galaxy, Ursa Major
Large, low-surface brightness spiral galaxy. I haven’t been able to see it in binoculars (or the finder), but it was visible in the Vixen SP-102 (at 42x) as a faint misty patch, roughly circular in shape. The XT10 starts to show some of M101’s elusive structure, but you need to catch it near the zenith on a night of excellent transparency to get the best out of it.
92x: (Also observed at 50x and 133x, but the Ethos provides the best view by far.) Core of the galaxy visible with direct vision. Stellar nucleus with a faint 12.5 magnitude foreground star superposed on the face of galaxy to the north (this star is a very useful marker, as it’s easy to lose your bearings when observing objects near the zenith). Suggestion of discontinuous spiral arms, and hint of HII/star-forming regions with averted vision, right on the threshold of visibility. After seeing it a few times, the feature I’m most confident of is a nebulous spot east of the core (most likely NGC 5461 or 5462). There also seems to be a tiny faint spot (possibly a star) west of the core.
On a really good night the spiral pattern is vaguely discernible with averted vision, looking a bit like an untidy old spring (and it still doesn’t come close to the best views of M51). The eastern spiral arm is particularly loose, though it’s easy to confuse this with the nearby curving line of field stars, which give the galaxy the appearance of a ragged number 6.
On the same exceptional night I glimpsed M101’s spiral, I also observed several of its neighbouring galaxies (all at 92x):
NGC 5474: Visible to the south-southeast of M101 as an amorphous round glow. Gradually brighter towards the core with averted vision, but the core itself appears offset from the centre in the direction of M101.
NGC 5473: Very small, round, condensed galaxy near a bright star, north and a little east of M101. Easy to overlook because of its diminutive size. Bright core.
NGC 5485: Same distance again, roughly east of NGC 5473, but larger and fainter. Brighter towards centre with averted vision. Apparently a background galaxy rather than a physical companion of M101.
NGC 5422: North-northwest of M101, opposite side to NGC 5474. Small needle-streak of light pointing back towards M101. Forms a near-rectangular trapezoid with three field stars of equal brightness. Bright core with averted vision. Most likely another background galaxy.
M102* (NGC 5866), lenticular galaxy, Draco
*Although many sources now regard M102 as a duplicate observation of M101 rather than a separate discovery of NGC 5866, the latter is still worth observing regardless of its disputed status (and it’s refreshingly bright if you’ve just come from M101).
92x, 133x & 171x. Bright little lens-shaped galaxy forming a triangle with two field stars. Symmetrical shape and no detail that I could see (I’m not sure if the central dust lane is within reach of my scope), although the 7mm DeLite seemed to show fainter “extensions”, increasing the length of the galaxy.
See also:
NGC 5907, Splinter Galaxy, Draco
92x and 133x: Large, razor-thin, edge-on galaxy, well deserving of its nickname. Quite faint (compared to say, NGC 4565) but still an exquisite sight, particularly with averted vision. Also brighter towards the centre with averted vision. Faint star west of the nucleus.
M103 (NGC 581), open cluster, Cassiopeia
133x: Pretty little triangular cluster with a prominent red star at the centre. A nudge of the scope to the northeast is a tiny little cluster of stars, the four brightest of which form an almost dead straight line. Not plotted in the PSA, but confirmed in Uranometria as Trumpler 1.
This whole region (between Delta and Epsilon Cas) is rich in open clusters, the best of which is arguably the horseshoe-shaped cluster NGC 663 (I would even rate it as superior to M103). The TV60 at 15x shows both M103 and NGC 663 plus several other clusters all in the same field of view.
M104 (NGC 4594), Sombrero Galaxy, spiral galaxy, Virgo
133x: Long, saucer-shaped galaxy with a central bulge and a bright stellar core. Long, straight, dark dust lane offset to the south, clearly seen with averted vision. One of the rare instances where a galaxy’s visual appearance lives up to (or at least approaches) its photographic appearance.
M105 (NGC 3379), elliptical galaxy, Leo
92x: Round, condensed galaxy with a bright, stellar core. Brighter than nearby M95 and M96, but lacking in detail. Visually, the most appealing thing about M105 is that it shares the same field of view with two other galaxies: NGC 3384 and NGC 3389. The former, NGC 3384, is smaller than M105 and also has a bright, stellar core. NGC 3389 is visible with averted vision as a faint ellipse, angled away from M105 towards three field stars. Easy to overlook if you’re not paying attention.
M106 (NGC 4258), spiral galaxy, Canes Venatici
133x: Quite large and bright – inviting higher magnification. The most distinctive feature is one bright spiral arm on the northern side of the galaxy.
171x: Northern spiral arm remains bright; appears to be a dark lane on the western side of the galaxy, slanting diagonally south. At this higher magnification the core itself seems slightly elongated in a northwest-southeast direction.
240x: Large bright core and a shallow s-shaped spiral – the southern arm is not as easy to see as the northern one. Averted vision seems to suggest a dark area just north of the nucleus.
Three neighbouring galaxies can be picked up in the immediate vicinity of M106:
NGC 4346
133x & 171x: Small spindle galaxy aligned east-west, with a bright stellar core. Located east (and a little south) of M106, with a bright star midway between the two.
NGC 4220
133x & 171x: Faint elongated galaxy north and west of M106, aligned northwest-southeast. Brighter towards the centre with averted vision.
NGC 4217
133x and 171x: Faint streak of light west of M106, aligned northeast-southwest. Easy to overlook because its visibility is hampered by a bright 9th magnitude star to the north and another fainter one west, lying almost on top of the core.
M107 (NGC 6171), globular cluster, Ophiuchus
133x: A relatively faint, condensed globular cluster, smaller than M14. Grainy in averted vision with a brighter, mottled core. The cluster is surrounded by five field stars which make up a distinctive kite or cruciform shape.
M108 (NGC 3556), barred spiral galaxy, Ursa Major
133x: Large, extended galaxy; seems “mottled” with averted vision. 12th magnitude foreground star near the nucleus and another one to the west. Shares same low-power field with the Owl Nebula (M97).
M109 (NGC 3992), barred spiral galaxy, Ursa Major
133x: Large, faint galaxy elongated along a southwest-northeast axis; brighter towards centre. Bright 10th magnitude star off the south-western edge; fainter 11th magnitude one off the opposite edge. Seems somewhat faint for a Messier object (albeit a belated entry), especially given all the much more obvious NGC galaxies in and around the same constellation.
See also:
NGC 3953, galaxy, Ursa Major
133x: Moderately bright galaxy, rivalling nearby M109. Somewhat brighter towards centre. Misty/ghostly outer envelope – swells with averted vision.
M110 (NGC 205), dwarf elliptical galaxy, Andromeda
133x: Ghostly oval of light; quite large. Obviously faint compared to M31 and M32, but shows up well even in a 60mm scope. Would probably seem reasonably bright for a galaxy if it were more distant from Andromeda.
If M110 seems too easy, M31 has a couple of much more challenging satellite galaxies lurking across the border in Cassiopeia. NGC 185 appears as a soft round glow, but very dim and featureless. NGC 147 is fainter still, and as yet I haven’t been able to see it.
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