Creede Dark Skies: Some more star clusters and four nearby stars

The telescope used last night was an Astro-Tech AT72EDII refractor with an Astro-Tech 0.8x focal reducer. This combination gives a focal length of 346 mm at f/4.8. This reducer shows very little corner vignetting on the micro-four-thirds sensor of the E-M5iii camera, unlike the Metabones 0.71x Speedbooster. Sky brightness was 19.72 mpsas, which is on the better side of average for this location. Exposures were either 30 sec or 40 sec at ISO 1600.

NGC 2281, an open cluster in Auriga. 2-deg FOV.

M44, the "Beehive Cluster", in Cancer. 2-deg FOV.

M67, the "Golden Eye Cluster", in Cancer. 2-deg FOV.

NGC 2232 in Monoceros. 2-deg FOV.

NGC 2244 in Monoceros. 2-deg FOV.

The open cluster NGC 2244 lies at the heart of the Rosette Nebula in the constellation Monoceros. The nebula is too faint to show up easily in a 40-sec exposure with this optical configuration, but some extreme contrast enhancement reveals its presence:

There are 37 star systems closer than 15 light years (ly). Eleven of these systems contain either two or three stars, so there are 50 stars total within this distance. Only seven of these 50 stars (or pairs) are bright enough to be seen without optical aid. Most of the nearest stars are red dwarfs (38 out of 50), all of which require a telescope to be detected. This is the most numerous type of star in the galaxy.

Images were obtained for three of these nearby red-dwarf stars: Ross 614 in Monoceros, Luyten's Star in Canis Minor, and DX Cancri in the constellation Cancer.

Finder chart for three nearby red dwarf stars. credit: SkySafariAstronomy.com

Ross 614 is a red-dwarf double star that lies just north of the open cluster NGC 2232 in the constellation Monoceros. Ross 614 is 13.36 ly distant and is the 29th closest star system. Its two components have magnitudes of 11.2 and 14.2.

Ross 614, top circle. NGC 2232, bottom circle.

Ross 614. 1-deg FOV.

Luyten's Star is a 12.4-magnitude red dwarf that lies about 3 deg from the bright star Procyon in the constellation Canis Minor. Procyon is a double star that is the 8th brightest star and the 13th closest star system at 11.4 ly . Luyten's Star is the 22nd closest system at a distance of 12.35 ly. These two stars are also close companions in space, with a separation of about 1.2 ly.