Object Analysis

The Lagoon Nebula (Messier 8) is a giant interstellar cloud in the constellation Sagittarius. It is classified as an emission nebula and H II region. The nebula is estimated to be between 4,000 and 6,000 light-years from the Earth. It is one of only two star-forming nebulae faintly visible to the naked eye from mid-northern latitudes.

Within the nebula is the open cluster NGC 6530, composed of 50 to 100 hot stars of spectral type O and B. These massive stars emit intense ultraviolet radiation that ionizes the gas, causing it to glow. The nebula contains a number of Bok globules—dark, collapsing clouds of protostellar material.

The name "Lagoon" derives from the wide, lagoon-shaped dust lane that crosses the center of the nebula's bright region. High-resolution images reveal twisting tornadoes of hot gas and intense stellar winds carving out cavities in the molecular cloud.