Crescent Nebula: Image obtained by Harold Vander Molen (member of Black Hills Astronomical Society) in Rapid City, SD - 2017
Crescent Nebula: Image obtained by Harold Vander Molen (member of Black
Hills Astronomical Society) in Rapid City, SD - 2017
The Crescent Nebula (also known as NGC 6888, Caldwell 27, Sharpless 105) is an emission nebula in the constellation Cygnus, about 5000 light-years away from Earth. It was discovered by Friedrich Wilhelm Herschel in 1792.
This bi-color image is about 17 hrs of total integration, and was taken with a QHY16200A camera. The telescope used was a Celestron EdgeHD 9.25 with a focal length of 2350mm.
27x 1200 sec Ha(5nm) @-20C exposures
27x 1200 sec OIII (3nm) @-20C exposures