M21 (NGC 6531), open cluster, Sagittarius
92x and 133x: Rich cluster with bright stars; not particularly condensed; a little north of M20. Bright pair near centre, with adjacent star pattern in the shape of a teacup, or a backwards “3”.
M22 (NGC 6656), globular cluster, Sagittarius
92x: Very large “flattened” globular brimming with stars – spectacular in the Ethos. A few dozen stars resolved in direct vision and countless more with averted vision; very impressive considering its low altitude. Appears to be a dark lane or rift on the western side. If you live in southern Britain and you’ve got a decent-sized scope, it’s worth persisting with this cluster; it can often look washed-out at first glance, but on a good night it can surpass even M13 in visual splendour.
133x: Seems quite loose at this magnification, but still well resolved and the rift on leading side (west of the core) is more prominent.
See also:
NGC 6642, globular cluster, 133x: Small round blur, west and a little north of M22. Condensed core with averted vision.
M23 (NGC 6494), open cluster, Sagittarius
133x: Rich, large cluster of uniformly bright stars, filling the field of view. Bright star to north. Concentration of fainter stars at western end of cluster.
92x: better-framed at this magnification. The stars seem to form the outline of a flattened starfish or a magic lantern.
Southwest of M23 is a pair of interesting objects in the same field of view:
NGC 6440, globular cluster, Sagittarius
133x: Faint condensed blur in same field as NGC 6445, brightens with averted vision.
NGC 6445, planetary nebula, Sagittarius
92x: Conspicuous-sized ghostly disc on the western side of Sagittarius. Quite bright in OIII. Averted vision transforms the disc into a ring, with brighter segments to the north and south.
133x (no filter) and 171x (OIII): Quite faint without the filter (one of the consequences of averted vision is that this nebula is easier to see when you’re looking straight at 6440). With the filter in place, 6440 effectively disappears and 6445 becomes much more obvious. The higher magnification makes the misshapen ring structure more apparent. Most prominent feature is a bright condensation on the northern rim.
M24 (IC 4715), Small Sagittarius Star Cloud, Sagittarius
From my location the naked-eye view of Sagittarius is usually limited to its brightest stars (the “teapot” asterism) and not much else, but on a rare good night M24 is visible as a hazy patch, a little smaller than the Scutum star-cloud further to the north. 7x50 binoculars reveal it to be sprinkled with stars, the brightest ones forming a distinctive almond shape.
At 92x in the XT10 it’s transformed into a staggeringly rich star-field. Even in the Ethos it covers several fields of view, but this is probably the best eyepiece for appreciating this region’s grandeur and sheer density of stars. The dark dust clouds which give M24 its distinctive sharp-edged appearance are conspicuous by their relative absence of stars. I know this region is actually a window into a deeper part of the galaxy, but the impression I get is of an iceberg of stars calving off from the ice-shelf of the Milky Way.
M25 (IC 4725), open cluster, Sagittarius
92x and 133x: Bright, large cluster, with a distinctive “D” shaped pattern of stars at the centre. Unlike M23, the stars come in a range of brightnesses. Well-framed in the Ethos.
M26 (NGC 6694), open cluster, Scutum
92x and 133x: Small cluster somewhat overshadowed by M11 to the north. The brightest four stars make a kite shape, with a curving chain of stars to the north and a fainter spray of stars to the east. The central part of the cluster seems strangely vacant.
M27 (NGC 6853), Dumbbell Nebula, planetary nebula, Vulpecula
The only planetary nebula (from my location) that’s visible in binoculars, showing as a small but clearly non-stellar disc of light.
133x: Very bright with or without the Ultrablock. Appears sharper on one side and ever so slightly bluer than M57. With the OIII filter at 133x, M27 becomes almost too bright – the apple-core fills in to become a football. But hard to make out detail other than a sharp edge on one side.
171x (no filter): Large and boxy at this power; no obvious colour. Brightest field star on the western corner, with a couple more visible through the northern half of the nebula. The central illuminating star isn’t immediately obvious against the nebulous background, but becomes visible with averted vision, popping in and out of view with the seeing. Sources seem to vary on the brightness of this star: some have it at 13th magnitude; others have it nearer 14th magnitude. Based on my observation, I would put it nearer 13 than 14.
240x: The "apple-core" takes on a more boxy appearance at 240x. Distinct, sharp cut-off in brightness on one edge, and strong hints of structure within the nebula – most prominent being the diagonal bar commonly seen in photos like the one above.
M28 (NGC 6626), globular cluster, Sagittarius
92x and 133x. Bright, condensed globular. Grainy appearance. Hint of resolution with averted vision. Somewhat overshadowed by its proximity to the spectacular M22.
See also:
NGC 6638, globular cluster, Sagittarius
133x: Condensed blur just east of Lambda Sagittarii, fainter than M28.
NGC 6629, planetary nebula, Sagittarius
171x + OIII. Very small, bright little disc, north of M28. I may have seen the central star with averted vision, but it was tough to separate from the nebula.
M29 (NGC 6913), open cluster, Cygnus
92x and 133x: Visible as a partially resolved fuzzy patch in the finder. The eyepiece view shows a compact, basket-shaped little group of eight bright stars and at least half a dozen fainter ones. This cluster is kind of like a pocket Pleiades. Not particularly rich or condensed, but the wide field of view of the Ethos shows it quite nicely in the wider context of the surrounding Milky Way.
M30 (NGC 7099), globular cluster, Capricornus
133x and 240x: Small condensed blur, just east of a bright 8th magnitude leading star. Starts to resolve with averted vision despite its low altitude: the most prominent features are a straight line of stars to the north and another fainter one (not radial to the core) to the northwest, giving the cluster a very distinctive lopsided, spiky appearance.
When you’ve finished observing this object, switch to low power and get a narrowband or OIII filter ready, because the Helix Nebula is approaching from the east.
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