Crescent Nebula

The Crescent Nebula is an evocative emission nebula located roughly 5,000 light-years from Earth. Its distinctive "shells" of gas result from the interaction between the faster stellar winds emanating from the central star and the slower-moving gases expelled when the star transformed into a red giant hundreds of thousands of years ago. This striking cosmic portrait is presented in Hydrogen (Red) Oxygen (Green) Oxygen (Blue) with over 10 hours of exposure time.