The Coalsack Nebula is a prominent dark nebula located in the southern sky, part of the Constellation Crux, or the Southern Cross. It is one of the most recognizable dark patches in the Milky Way, appearing as a large, dark silhouette against the bright background of stars. The nebula is about 600 light-years away from Earth and spans approximately 50 light-years across. This nebula is composed of dense clouds of dust and gas, which block the light from stars behind it. The Coalsack Nebula is an important area for studying star formation, as it contains regions where new stars may be born. Its distinct shape and visibility make it a favorite target for amateur astronomers and astrophotographers.