The Cocoon Nebula

About This Photograph

The Cocoon Nebula is a cloud of gas and dust in the constellation of Cygnus, high overhead in summer months for northern-hemisphere observers. The nebula is illuminated by the bright central star visible in this photograph. This star formed from the gravitational collapse of part of this cloud some 100,000 years ago, and now it makes its own stellar nursery visible to us. The nebula shines mostly in the characteristic red light of ionized hydrogen gas, though the fainter outer reaches of the cloud show other colors due to ionization of other elements such as oxygen and sulfur, as well as from reflection of the starlight. Even more fairly visible are clouds and filaments of gas and dust too poorly illuminated to shine, but seen here in silhouette against the backdrop of the brighter parts of the nebula and the background stars of the Milky Way.

Also known as Caldwell 19, Sharpless 2-125, and IC 5146, the Cocoon Nebula is about 4,000 light years from earth.