Rosette Nebula - NGC 2237, NGC 2238, NGC 2239 and NGC 2246
Object Type - Emission nebula with open cluster (NGC 2244)
Constellation - Monoceros
The Rosette Nebula is a large emission nebula located in the constellation of Monoceros. The brighter portions of the Rosette have been assigned different NGC numbers: 2237, 2238, 2239, and 2246.
The cluster of stars at the center of the Rosette, collectively known as NGC 2244, are super-hot O-type stars which provide the ultraviolet radiation which causes the gas of the nebula to glow. It is believed that the radiation pressure from the stars of NGC 2244, which formed from the nebula, is the cause of the central hole. Astronomers also believe that the central stars formed less than 1 million years ago and that the intense stellar wind from these stars is presently dissipating the nebula.
The Rosette Nebula is believed to be 5,500 light years distant with an estimated diameter of 130 light years.
Follow this link for more information on the Rosette Nebula: www.seds.org/messier/xtra/ngc/n2244.html
November 17, 2009
An RGB image consisting of 6 six minute exposures for each color channel. [Total exposure time = 1.7 hours]
Vallecito County Park, Anza-Borrego Desert, San Diego County, California
Optics - Takahashi Epsilon 160 f/3.3 astrograph
Mount - Astro-Physics AP 1200 GTO
Camera - SBIG STL-11000M