February Night Sky

February is a good month to see two very different nebulae, the Eskimo and the Rosette.

The Eskimo Nebula, NGC 2392 is a planetary nebula in Gemini. It was discovered by Herschel, though after he had moved to Slough. Planetary nebulae have nothing to do with planets , but tend to be circular and quite bright (hence the name), and may be quite small. The Eskimo nebula certainly fits the bill, as it is about 45″ across (about the same angular size as Jupiter), and has a very distinct, complex central bright area, surrounded by a fainter halo (once seen as an Eskimo face and hood). It is in fact the result of an explosive outburst from the central star, which can still be seen in a large telescope. Images show great detail, but it is also rewarding visually, especially at high magnification.

It is high up in the sky on winter nights. If you start from Pollux, the more southerly of the heavenly twins that are the most prominent feature of Gemini, it is then rather less than 10 degrees towards Orion. The smaller red circle on the map below shows exactly where to find it.

The Rosette Nebula is further south, in Monoceros. By contrast , this is a large area of star forming gas surrounding the open cluster NGC 2244. The star cluster itself is very easy to find. Its most noticeable feature is an array of 6 quite bright stars in an elongated, but slightly bent, rectangle. The Rosette Nebula surrounds this cluster completely, but is quite faint, and so big (over 1 degree across) that you won’t be able to fit it into your field of view. But it is hard to spot visually.  A O III filter, which excludes all light except that produced by energised Oxygen in the nebula should help make the Rosette, (and the Eskimo Nebula) easier to see.

You can get to NGC 2244 by starting at the bright triangle of stars to the west of Betelgeuse,then  coming back through Betelgeuse, continuing in the same direction to a bright-ish star, which is Epsilon Monocerotis, and then a couple of degrees further east.

The larger red circle marks the spot on the map below.

Both of these nebulae can be picked up in binoculars, but both also benefit from close observation on a dark night in the biggest telescope you can get your hands on!


February Nebulae