M36 – Open Cluster in Auriga



M36 – Open Cluster in Auriga

Mag 6.3,
12 arcminutes
RA 5:36 Dec 34 08'
This from SEDS.ORG:


Discovered by Giovanni Batista Hodierna before 1654.


This is the first of three bright open clusters in the southern part of constellation Auriga, included in Messier's catalog (the other two are M37 and M38). All 3 have been first recorded by Giovanni Batista Hodierna before 1654. Charles Messier included it in his catalog on September 2, 1764.


M36 is about 4,100 light years distant, so that its angular diameter of 12' corresponds to about 14 light years. It has about 60 proven members, the brightest of which are of apparent mag 9 and spectral type B2; the luminosity of the brightest member is about 360 times that of the Sun. Many of these bright stars are rapidly rotating, as shown by their broadened spectral lines, an effect which is also found for the bright type B members of the Pleiades (M45). If it were at the same distance (i.e., 10 times closer), this cluster would look as conspicuous as and very similar to the Pleiades.


As it is quite young (about 25 million years), it contains no red giants, in contrast to its neighbors M37 and M38, which lie roughly at the same distance.


ST-10XME with Tak FSQ
Astrodon RGB filter set
4 x 5 minutes each of RGB
Self guided on an AP900GTO
Flesherton, Ontario, Canada
Dec 19, 2006
Ambient temp +2C; camera temp -20C; Moon just before new
Images acquired, darks & flats applied, aligned in CCDSoft v5.0
Images debloomed and combined in Maxim
Colour channels assembled in PS CS2.
Imported to PS CS2 via FITS Liberator then Levels only; noise reduction in PS CS2