The Rosette Nebula (also known as Caldwell 49) is a large spherical H II region (circular in appearance) located near one end of a giant molecular cloud in the Monoceros region of the Milky Way Galaxy. The open cluster NGC 2244 (Caldwell 50) is closely associated with the nebulosity, the stars of the cluster having been formed from the nebula’s matter.
The cluster and nebula lie at a distance of some 5,000 light-years from Earth and measure roughly 130 light years in diameter. The radiation from the young stars excites the atoms in the nebula, causing them to emit radiation themselves producing the emission nebula we see. The mass of the nebula is estimated to be around 10,000 solar masses.
Imaging telescopes or lenses: Takahashi FSQ130ED Imaging cameras: FLI ML16200 ADT Mounts: Takahashi EM 400 Temma 2M Guiding telescopes or lenses: Takahashi FS60CB Guiding cameras: QHY CCD QHY 5 II Focal Extender / Reducer: None Software: Sequence Generator Pro SGP (for capture) PHD 2 (guiding), Astro Pixel Processor & PixInsight, Filters: Astrodon Ha, OIII, SII. Accessories: Robofocus Focuser, ATIK EFW3 Frames: Astrodon Ha 30 x 10' Astrodon OIII 30 x 10' Astrodon SII 36 x 10' Total integration = 16 hours.