The Crescent Nebula is located in the constellation Cygnus and is an emission nebula. The nebula has the catalogue designations NGC 6888, Caldwell 27 and Sh2-105 and can be seen from the northern hemisphere in summer. The nebula is about 5'000 light years away from our solar system.

This nebula is special because it is formed by the fast stellar wind of a rare Wolf-Rayet star. The result of this wind ejection are two shock waves, which can be clearly seen in my image. A Wolf-Rayet star is an evolved massive star that has lost its outer hydrogen layers and only fuses helium or heavier elements in its core. Typical surface temperatures are at least 20'000 K hotter than normal stars. Because of their extreme heat, they are also very bright.