PIX4622024: Nebula of the horse's head in Orion (IC 434) - The Horsehead is located in the constellation of Orion, slightly below the left - most star of the three that form the Hunter's belt. It is part of a vast molecular cloud of dust and gas that includes the Great Orion Nebula and extends throughout the entire constellation as well. It was first seen through photographs taken by E. Pickering in January 1900. The red coloration is the result of glowing hydrogen gas located primarily behind the formation. Here, we see the Horsehead as it appeared 1,500 years ago, due to distance and the time it takes light to travel. The bright complex of dust and gas below the Horsehead reflects the light given off by the bright star near it's center and is one of the brightest examples of reflection nebulae in the northern sky. The central star is surrounded with a thin shell of hydrogen that glows red by emitting it's own light in a rare example of a unique process called vibrational fluorescence. There are also an number of dark clumps of gas that represent stellar nurseries containing one or more new stars hidden within. The Horsehead can be challenging to see visually, but under very dark skies, many observers report that it can be glimpsed in silhouette with a ten inch telescope and an H - beta filter that accentuates the background hydrogen glow / Bridgeman Images