The dark cloud of dust and gas is a region in the Orion Molecular Cloud Complex where star formation is taking place. 4′, on nebulous strip extending south from ζ Orionis', cataloguing the dark nebula as Barnard 33. Barnard, describing it as: 'Dark mass, diam. One of the first descriptions was made by E. The nebula was first recorded in 1888 by Scottish astronomer Williamina Fleming on a photographic plate taken at the Harvard College Observatory. It is one of the most identifiable nebulae because of its resemblance to a horse's head. The Horsehead Nebula is approximately 422 parsecs or 1,375 light-years from Earth.
It appears within the southern region of the dense dust cloud known as Lynds 1630, along the edge of the much larger, active star-forming H II region called IC 434. The nebula is located just to the south of Alnitak, the easternmost star of Orion's Belt, and is part of the much larger Orion Molecular Cloud Complex. The Horsehead Nebula (also known as Barnard 33) is a small dark nebula in the constellation Orion. The reflection nebula NGC 2023 is in the bottom left corner and the nebula itself near the center, in the shape of the head of a horse.
