Object Information:                  The Rosette Nebula (NGC 2237),
                                                Object Type - Emission nebula with open clusters,
                                                Constellation - Monoceros,
                                                Distance - 4,900 light years,
                                                Size - 90 light years across.

Description:    The Rosette Nebula is an emission nebula located in the constellation of Monoceros, the Unicorn.  The Rosette Nebula is believed to be 4,900 light years distant with an estimated diameter of 90 light years.  The central "hole" is estimated to be 30 light years across.

    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 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.

Imaged at:                                 San Diego Astronomy Association site near Tierra del Sol, San Diego County, California;
                                                 Elevation - 4000 feet

Equipment:                                Optics - Takahashi E-160 Newtonian astrograph f/3.3
                                                 Mount - Losmandy G-11,
                                                 Camera - Nikon FM2,                                                
                                                 Filter - none,

Exposure Information:               December 17, 2001 and December 18, 2001
                                                 A median combination of six, 35 minute guided exposures using the SBIG STV,

Film:                                         Kodak Ektachrome E 200, push processed 1 stop

Image Processing Software:      Registration and combination of images - RegiStar, Final processing - Photoshop 6.01

Image Processing Steps:            1)  All negatives were scanned with a Polaroid Sprint Scan 4000 at 4000 dpi;  2)  All digitized images were then registered and combined using RegiStar, the "average" combination method was used; 3) The combined image was then processed and converted to JPEG format using Photoshop 6.01.