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Saddle Up: The Incredible Story of the Horsehead Nebula
An iconic nebula and the woman who discovered it.
Located approximately 1,500 light-years away in the constellation of Orion is a faint dust cloud that has captured the imaginations of millions of astronomy enthusiasts since its discovery in 1888. Thanks to its resemblance to a knight’s chess piece, that faint dust cloud — better known as the Horsehead Nebula — has become one of the most iconic and identifiable nebulae in the Milky Way Galaxy.
What is the Horsehead Nebula?
The Horsehead Nebula is a dark nebula — a type of interstellar cloud so dense that it blocks light from objects behind it.
Color images of the Horsehead Nebula show the cloud silhouetted against a reddish-pink backdrop. The red color comes from hydrogen gas behind the nebula that has been ionized by radiation from the nearby star Sigma Orionis.
The nebula is part of the Orion Molecular Cloud Complex — an active star-forming region that contains very young stars and stars with protoplanetary discs. The Horsehead Nebula itself has enough mass to create about 30…
