Rosette Nebula - Neck Tie

The Rosette Nebula (Caldwell 49) is a large circular nebula in the constellation of Monoceros. It is overhead in the Northern Hemisphere between December and March. It is approximately 5,000 light years from Earth and roughly 130 light years in diameter. It is primarily a Hydrogen Alpha (Ha) nebula whose atoms are excited by the star cluster, NGC 2244, located in the centre of the nebula. This image was taken over the course of a week in March of 2018 from Gainesville, VA and required a total of 14.86 hours of exposure time. 78+ images were taken at different wavelengths only emitted by the nebula. The wavelengths were 500.7nm, 656.28nm, and 672.4nm. These wavelengths are called Oxygen III (OIII), Hydrogen Alpha (Ha), and Sulphur II (SII) respectively. These are the wavelengths the Hubble telescope uses to image the universe. It’s called "The Hubble Palette". The images were later stacked and averaged. To create a colour RGB image, SII is mapped to red, Ha is mapped to green and OIII is mapped to blue. They are combined to form a final RGB image.