Nebulae in Orion, optical image. North is at left. The image reveals the extent of the nebulosity in the constellation Orion. The great Orion nebula (M42 and M43) is at upper right (pink) with the reflection nebula NGC 1977 (purple) to the left of it. At lower left is the Horsehead nebula, formed by the silhouetting of the dark nebula B33 onto the red emission nebula IC 434. Below and left of this is the brighter Flame nebula (NGC 2024), which is crossed by a dark dust lane. The bright star above the Flame nebula is Alnitak (Zeta Orionis) and the star of equal brightness above and left of it is Alnilam (Epsilon Orionis). These two stars are both in Orion's Belt.