NGC 2237 – The Rosette Nebula in H-alpha | Craig & Tammy Temple

Craig & Tammy Temple
Location of photo
Hendersonville, TN
Date/Time of photo
February 13 & 14, 2011
Telescope: William Optics ZenithStar 66 Accessories: William Optics 0.8x FR/FF vII; Dew control by Dew Buster Mount: Orion Atlas EQ-G (hyper-tuned by Astrotroniks) controlled by EQMOD Guiding: TS-OAG9 Off-axis, using a Starlight Xpress Lodestar via PHD Camera: Atik 314L+ monochrome CCD @ -10.0C with Atik EFW2 Filters: Baader 7nm H-alpha Exposure: 40 x 10min. (6hr. 40min.) Acquisition: Images Plus Camera Control v4.0b Processing: Bias calibration in Images Plus v3.80; bad pixel map in Nebulosity 2.3.6c; Registration and combine in RegiStar Post-processing: Adobe Photoshop CS4; Carboni’s Tools
The Rosette Nebula (NGC 2237, Caldwell 49, Sh2-275) is a large HII star-forming region that lies just east of Orion in the constellation Monoceros. This large molecular cloud is comprised of several smaller parts which were discovered by three different astronomers: John Herschel (NGC 2239), Albert Marth (NGC 2238) and Lewis Swift (NGC 2237 & 2246). In 1690, John Flamsteed discovered the Rosette's central open cluster, NGC 2244. From Earth, the nebula is approximately 5000 light years distant and appears to be about 1 degree across - roughly 5 times the size of the full Moon. At an apparent magnitude of 9.0, the nebula is impossible to see with the unaided eye making it's discovery difficult.