The image shows IC 5146, also known as the Cocoon Nebula. It is both a reflection and an emission nebula about 3300 light years away in the constellation of Cygnus. A reflection nebula reflects the light of nearby stars, while an emission nebula is formed when light from nearby stars ionizes the gas and makes the nebula glow. This nebula does a little of both. The IC 5146 actually refers to the star cluster at the center of the nebula while Sh2-125 is the actual nebula. The nebula is about 15 light years in diameter. You can also see the dark nebula Barnard 168 which surrounds the nebula and forms a dark trailing cloud extending to the west of the nebula (to the right in the picture).
August 27, 2011
Location: Rancho Hidalgo, NM
Telescope: TEC-140 (F7)
Camera: SBIG ST-8300M
Mount: AP900 GTO
Luminance: 12x10 minutes
Red: 6x10 minutes
Green: 6x10 minutes
Blue: 6x10 minutes