<Tr> <Th> Designations </Th> <Td> Barnard 33, LDN 1630, </Td> </Tr> <Tr> <Td_colspan="2"> See also: Lists of nebulae </Td> </Tr> <P> The Horsehead Nebula (also known as Barnard 33) is a dark nebula in the constellation Orion . The nebula is located just to the south of the star Alnitak, which is farthest east on Orion's Belt, and is part of the much larger Orion Molecular Cloud Complex . The nebula was first recorded in 1888 by Scottish astronomer Williamina Fleming on photographic plate B2312 taken at the Harvard College Observatory . The Horsehead Nebula is approximately 1500 light years from Earth . It is one of the most identifiable nebulae because of the shape of its swirling cloud of dark dust and gases, which bears some resemblance to a horse's head when viewed from Earth . </P> <P> The dark cloud of dust and gas is a region in the Orion Molecular Cloud Complex where star formation is taking place . It is located in the constellation of Orion, which is prominent in the winter evening sky in the Northern Hemisphere and the summer evening sky in the Southern Hemisphere . This stellar nursery, as it is known, can contain over 100 known kinds of organic and inorganic gases as well as dust; some of the latter is made up of large and complex organic molecules . </P>

How far is the horsehead nebula from earth