This month, we turn at a T-junction, pop into a house and admire the Christmas Tree
1. The Meissa Cluster
Recommended equipment: 10×50
When you look at Orion’s ‘head’ through binoculars, you can immediately see why it looks distinctly fuzzy to the naked eye: it is a small cluster of stars. The dozen or so stars that you can resolve are dominated by the brilliant white mag. +3.5 Meissa (Lambda (λ) Orionis). The other two bright stars in the field of view are the sapphire-blue mag. +4.4 Phi1(φ1) Orionis and deep-yellow mag. +4.1 Phi2(φ2) Orionis.
2. The Christmas Tree Cluster
Recommended equipment: 10×50
The seasonally appropriate NGC 2264, the Christmas Tree Cluster, lies 6.5° south of Alhena (Gamma (γ) Geminorum), surrounding the slightly variable (mag. +4.6 to +4.7) distinctly blue star, S Monocerotis. S Mon is in the base of the narrow wedge of stars that form the inverted tree. There is a lot of interstellar dust in this region of the Milky Way, which is why there seems to be a paucity of faint stars.
3. NGC 2244
Recommended equipment: 10×50
About 2° east of mag. +4.4 Epsilon (ε) Monocerotis, there is a narrow rectangular group of stars a bit less than 0.5° long that is quite difficult to identify as a distinct cluster; it looks more like a slightly denser accumulation in the Milky Way. You should see about a dozen stars but, unless you have exceptional skies, don’t expect to detect the surrounding glow of the Rosette Nebula that gave birth to them.
4. NGC 2301
Recommended equipment: 15×70
Our next cluster can be difficult to find, but it’s worth the effort. You’ll find it 5° west of mag. +4.1 Delta (δ) Monocerotis. It has been named ‘Hagrid’s Dragon’ but it looks more like a little T-junction of 8th- and 9th-magnitude stars. It covers a little more than 10 arcminutes and appears as a few brighter stars against the slightly mottled glow of the 40 or so fainter suns that comprise the cluster.
5. The Skinny Prince
Recommended equipment: 10×50
About 2.5° east of mag. +0.5 Procyon (Alpha (α) Canis Minoris), find five 6th(ish)-magnitude stars in the shape of a narrow ‘house’, reminiscent of Cepheus. There are some lovely colours here, especially the ruddy semi-regular variable BC CMi (mag. +6.14 to +6.42, with a period of about 35 days). It’s worth scanning the wider area to see what other colourful star fields you can find.
6. 14 CMi
Recommended equipment: 15×70
Your scan around the Skinny Prince probably included mag. +5.3 14 Canis Minoris. This deserves a closer look, ideally using larger binoculars. It is a triple star, with two much fainter companions. The brighter one (mag. +9.4) lies 102 arcseconds to the east; the other (mag. +9.8) is 137 arcseconds to the southeast of 14 CMi. Can you detect any colour difference between the two fainter stars?