Winter Clusters

30 December 2019, 20:00 – 23:15 GMT

A cool, still night, but relatively mild for the time of year (although my feet were very cold towards the end of the session.

Seeing: good
Transparency: a slight haze mixed in with smoke from somewhere, but still much better than the 25th.

This time I came prepared with a makeshift dew-shield for the 9x50 finder – constructed from a piece of black card and some duct tape. It doesn’t look pretty, but it worked a treat. The condensation (while nowhere near as heavy as the previous session) started to appear on the body of the XT10 after about an hour, but the finder remained dry throughout. With hindsight the conditions were probably good enough for imaging too – and maybe I should have done; clear moonless nights seem to be rarer than usual this winter.

As before, I started with a tour of the Auriga Messier clusters using the 13mm Ethos. M37 was the highlight once again, with the dark rifts and overall “beetle” shape showing up particularly well.

Betelgeuse has made the headlines recently and it does look noticeably dimmer to the naked eye (though probably not for the reason most professional astronomers would like). It was one of the first stars I learned to recognise by name, and I can’t remember it ever looking this subdued. Through the eyepiece of my still cooling telescope it regained some of its lost grandeur, appearing as a bright, boiling red-hued star.

NGC 2169, open cluster, Orion
Follow-up observation from last week, at 92x and 133x. Tilting my head 90 degrees really made the “37” asterism become obvious, although the top-left star of the “7” is rather faint compared to its companions. The double star Struve 848 is located in the top right corner of the “3”.

NGC 2194, open cluster, Orion
Faint “boxy” cluster. Looks like an inconspicuous misty patch at first glance, but gets more impressive the longer you look at it. Some stars resolved; even more with averted vision. Quite rich and dense. Long tail of stars extending to the south.

NGC 1662, open cluster, Orion
Sparse but distinctive bird-shaped cluster with long wings and a diamond-shaped asterism forming the head. Red-hued star at the neck of the diamond.

NGC 1807 & 1817, open clusters, Taurus
The poor man’s double cluster. The northern one (1817) is rich and faint while the southern one (1807) is sparse and bright, with a prominent triangle asterism at its centre. Both clusters are well-framed in the Ethos.

NGC 2403, galaxy, Camelopardalis
A galaxy I've struggled to locate in the past (it resides in a barren area of the sky), but the new finder made it much easier. At 92x it appeared as an amorphous cloudy patch with two bright field stars at either end and a fainter one off-centre. Averted vision revealed an extended faint outer region, presumably corresponding with the spiral arms, although no structure was seen on this occasion.

M45, Pleiades, Taurus
Although this cluster doesn’t need a finder, it certainly helps me get my bearings when switching back to the eyepiece (M45 is too large for the fov even at 50x). At 92x the Merope reflection nebula was visible mainly by contrast with its surroundings. The nebula was large and fan-shaped, but I couldn’t see any of the banded structure apparent on photographs.

M78, reflection nebula, Orion
As previous observations. Two stars embedded in fan-shaped swathe of nebulosity (like condensed version of the Merope nebula). Prominent dark gap between M78 and the more diminutive NGC 2071.

M42, Orion Nebula
Spectacular in the Ethos despite condensation starting to creep in. Five stars resolved in the Trapezium at 92x. Exquisite detail in and around the Huygens region. The little arc of nebulosity in the opposite cavity wall showed up really well in the Ethos; it wasn’t quite so obvious at 133x, despite the better contrast. The higher magnification is better for picking out fine detail in the core, but overall, the view in the Ethos was much more majestic. Adding the OIII to the Ethos reinforced previous observations with this filter: it filled in the northern half of M42, giving the nebula a lopsided, asymmetric appearance.

NGC 2174-5, emission nebula + open cluster, Orion
Nebulosity (2174) faintly seen with Ethos and OIII. Switching to the 9mm Nagler (no filter) revealed the central cluster (2175) – stars arranged in a neat little parallelogram.

Rigel, Beta Orionis
0.1 magnitude blue-white star (currently considerably brighter than Betelgeuse) with 7th magnitude companion 10 arcseconds away. Clean split at 92x and 240x, not hindered by diffraction spikes on this occasion. The best view I’ve had of this double.

M1, Crab Nebula, Taurus
At 133x it appears as a faint, amorphous “puff of smoke”. Not a "frame-filler" by any means, but still a potential imaging target for the TV60, after M45 and the Horsehead.

NGC 2022, planetary nebula, Orion
Quick look at 133x. Pretty little disc of light, somewhat faint tonight.

NGC 1999, reflection nebula, Orion
At first sight it appears as a small hazy halo surrounding 11th magnitude V380 Orionis. At 133x the dark hole is visible with averted vision.

IC 418 (aka the Spirograph Nebula), planetary nebula, Lepus
Very small, looked like a bloated blue star even at 133x. Much more obvious at 240x (5mm Nagler). A pretty little blue-green disc surrounding a bright 10th magnitude star. Maybe a very slight yellowish tinge to the central star, but admittedly that’s a stretch. No structure apparent on this first viewing, but the northern half of the nebula seemed brighter than the southern half.

M79, globular cluster, Lepus
Viewed at 240x. Faint (very low in sky) grainy fuzzball with condensed core. Distinct 12th magnitude star north of core – as noted previously.

Hind’s Crimson Star (aka R Leporis), carbon star in Lepus
Viewed at 240x. Didn’t seem especially bright (though currently listed as 7.6m), but striking red colour, like a glowing ember or coal. One of the reddest stars I’ve seen.


Other notes:
Didn’t see any frogs when I looked in the pond (although I did see one when I was imaging the moon the previous month), but I did hear a distinctly frog-like “plop” at one point.