Although I’ve been observing for many years, until fairly recently I didn’t think it would be possible to see all of the Messier objects from my home location, due to factors such as low altitude and light pollution. However, through a combination of luck and persistence, I’ve now completed the list and can present a summary of my observations as seen from a suburban (NELM 5.5) garden at 51.5 N. Where applicable, I’ve also included notes on nearby objects of interest, some of which share the same field of view as their more famous neighbours.
Note: I very much consider this a work in progress (and one that will likely never end); I may have seen all the Messier objects, but - as anyone who's gazed into the heart of the Orion Nebula will know - there is always more to see.
All observations were carried out with an Orion SkyQuest XT10 Plus Dobsonian reflector (unless otherwise stated) and the following Tele Vue eyepieces:
24 mm Panoptic (50x)
13 mm Ethos (92x)
9 mm Nagler (133x)
7 mm DeLite (171x)
5 mm Nagler (240x)
An Orion Ultrablock filter and an Astronomik OIII filter were used on some of the nebulae.
To break up the text, I’ve also included a few images, all of which were taken with a Tele Vue TV60 refractor and a Canon 80D DSLR, on a Vixen Super Polaris mount.
I might publish a PDF version of this list as well, if anyone's interested.
M1 (NGC 1952), Crab Nebula, supernova remnant, Taurus
133x: Appears as a faint, amorphous “puff of smoke”. The Ultrablock filter improves the contrast, but no detail to speak of other than a vaguely bi-lobed shape. The OIII filter makes it seem slightly bigger and a little more defined around the edges. From an astrophysical perspective, this is arguably the most important object in Messier’s catalogue, but visually it’s somewhat underwhelming (especially when compared to the spectacular Veil Nebula in Cygnus). One of those deepsky objects that can only really be appreciated when you understand what you're looking at.
M2 (NGC 7089), globular cluster, Aquarius
133x: Large, slightly elongated, and well resolved, particularly with averted vision. The brightest member is just to the east-northeast of the core (though this may be a foreground star). At 240x, there is an apparent asymmetry caused by two wings of stars sweeping back towards the west. The foreground star on the eastern side of the cluster seems to sit in its own pool of darkness, adding to the asymmetry.
M3 (NGC 5272), globular cluster, Canes Venatici
92x: In the Ethos it appears as a finely resolved ball of stars, with a very distinctive aquamarine tinge quite unlike any other globular cluster I’ve looked at. A dark lane is visible on the eastern side of the cluster, giving it a vaguely squared-off appearance; this becomes more obvious at higher magnifications.
133x: Averted vision reveals a roughly triangular pattern of star chains pointing west.
See also:
NGC 5466, globular cluster, Boötes
133x: Appears as an extended misty patch. Rich sprinkling of faint stars visible with averted vision, but no sign of the central condensation typically seen in globular clusters. Not striking as globulars go, but certainly unusual and worth tracking down.
M4 (NGC 6121), globular cluster, Scorpius
133x: Large, grainy globular; a little washed out due to its low altitude (-26 degrees), but still impressive. At least two dozen stars clearly resolved. It may be an illusion due to the way the brightest stars are arranged, but the core region is distinctly bar-shaped (on a north-south axis). This must be a superb sight from more southerly latitudes.
M5 (NGC 5904), globular cluster, Serpens
133x: A lovely, rich condensed cluster, rivalling M13 for spectacle. Well resolved most of the way to the core. It seems to me (and I’ve thought this before with the Vixen SP-102) that although M13 seems bigger and brighter overall, the brightest stars in M5 are brighter than the brightest ones in M13. Colour: a pale aquamarine tinge, though very subtle compared to M3. Stars appear “swept back” to the east.
Just southeast of the core there is a particularly prominent star which seems to vary in brightness from night to night. Another slightly less bright star is offset to the southwest, forming a tight triangle with two other fainter stars. Both of these stars are variables: V84 (an RV Tauri star) and V42 (a Cepheid) respectively. For more on this, see: https://skyandtelescope.org/observing/hunting-bright-variables/
Another distinctive feature is a chain of stars curling around the northeast side of the cluster, like a spiral arm.
At 171x the cluster is still spectacular; the greater contrast causing even more faint stars to pop out. The core isn’t fully resolved, but definitely speckled.
See also:
About a third of degree southeast of M5 lies a bright and closely paired double star (5 Serpentis), comprised of a whitish 5th magnitude primary and a 10th magnitude companion roughly 12 arcseconds northeast. Both the cluster and 5 Serpentis appear in the same field at 92x. On some occasions when I’ve looked at it the secondary seems to have a pale violet or indigo hue, but it’s very subtle and mostly likely caused by a contrast effect with the primary.
M6 (NGC 6405), Butterfly Cluster, open cluster, Scorpius
133x: Tough to observe this cluster through the XT10 because of its very low altitude. Large, loose collection of bright stars (often shimmering due to atmospheric turbulence). The brightest stars seem to form the outline of a watering can or a fat dragonfly.
M6 is better-framed at 92x, but still a little too large for the field of view. Has an almost “chunky” appearance at this magnification, reminiscent of M24. The butterfly shape is more apparent in the Vixen SP-102 at 42x. M6 is also visible in binoculars as a faint hazy patch with at least three stars resolved (sometimes more if conditions allow).
M7 (NGC 6475), Ptolemy Cluster, open cluster, Scorpius
The southernmost Messier object (it culminates at less than 4 degrees above my horizon), and the only one I can’t reach with the XT10. Fortunately it’s bright enough (when conditions allow) to be picked up in smaller scopes and even 7x50 binoculars. The latter show a faint hazy patch from which a few faint stars pop out over time.
At 40x (TV60 + 9mm Nagler) M7 appears faint and washed out, with enough stars visible to at least give a sense of a very large, splashy open cluster. The dozen brightest stars form a wavy x-shape with a double star at the centre. There is also a haze of unresolved stars, plus an incomplete ring of brighter stars surrounding the central cluster. Even if M7 were high enough to be visible in the XT10, the TV60 would still be a better choice of scope to view it simply because of the larger field of view (2 degrees in the 9mm Nagler).
In the Vixen SP-102 at 42x (24mm Panoptic, giving a 1.5-degree field) the ring of stars surrounding the core region of M7 give it a stretched-out appearance, like a spider’s web slowly being pulled apart.
M8 (NGC 6523), Lagoon Nebula, emission nebula with cluster, Sagittarius
Faintly visible to the naked eye on a really good night and shows up particularly well in binoculars. M8 is so large that even the Ethos (at 92x) barely contains it, but it’s a wonderfully complex region at this magnification. The unfiltered view clearly shows the key components: the bright star cluster NGC 6530, the nebulosity to the west, and the wide dark lane (the “laguna”) dividing the two. A little further west, the bright star 7 Sgr completes the line up, giving M8 the extended shape which is so distinctive in finderscopes and binoculars.
The nebulosity fills out considerably with the addition of the Ultrablock filter, revealing another patch to the south extending along the other side of the laguna into NGC 6530, and a large fainter band of nebulosity to the north, all separated by dark lanes. The brightest segment (the one clearly visible without a filter) is transformed into a dense, mottled patch of nebulosity.
The nebulosity becomes even more expansive in the OIII filter, filling most of the fov of the Ethos (at the expense of the starlight, which is greatly subdued). The large rift dividing the cluster from the brightest part of the nebula now looks a dark crescent surrounded by nebulosity. On a good night, M8 in this filter starts to resemble its photographic appearance (albeit without the colour).
At 171x + OIII filter M8 obviously loses some of its impact, but the brightest part of the nebula is easier to study - intensifying to a tight core that looks like it’s been pinched and twisted into the distinctive hourglass shape. The southern component of the hourglass is brighter, and a smattering of embedded stars is visible with averted vision.
See also:
NGC 6544: 92x. Small, faint globular, south-east of M8; very condensed core with averted vision – almost star-like. Faint star west; three more east.
NGC 6553: 92x. Large, extended globular, south-east of 6544 and M8; brighter towards centre, but not particularly condensed. Faint star just north-west of core.
Plus (if you can see this far south):
NGC 6520, 92x: A compact and very distinctive open cluster comprised of bright, colourful stars overlying a rich unresolved haze. Prominent orange star near the centre. This cluster stands out well despite its low altitude (-28 degrees declination).
M9 (NGC 6333), globular cluster, Ophiuchus
92x and 133x: Bright, asymmetric, grainy globular. Starts to resolve with averted vision. Apparent dark patches southwest of core give it a misshapen appearance.
See also:
NGC 6342, 92x: Faint, condensed blur, south of M9. Brighter core with averted vision. Faint star southwest of core.
NGC 6356, 92x: Bright, condensed globular, northeast of M9 and only a little smaller and fainter than its M-designated neighbour. No resolution, but some faint stars visible on the outskirts of the cluster.
M10 (NGC 6254), globular cluster, Ophiuchus
133x: A more “conventional” globular than nearby M12, appearing as a rich, condensed ball of stars. Most distinctive features are a wavy arm of stars to the north and an opposing one extending south (like the integral sign or the f-hole on a violin). Well resolved. Also, easily visible in binoculars and finderscope.
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