Messier 78 is a bright blue reflection nebula in Orion that lies two and a half degrees northeast of Alnitak (Zeta Orionis), the easternmost star in the belt of Orion. It is the brightest reflection nebula in the sky.

This area lies in a complex of reflection, emission and dark nebulosity that is part of the Orion molecular cloud, a giant star forming region. The complex also includes the Horsehead Nebula, Barnard's Loop, the Flame Nebula, and M42, the Great Nebula in Orion.

M78 is in the center of the image. Other nebulae in the area are cataloged as NGC 2071 to the right (northeast) of M78. NGC 2067 is to the northwest, just below M78, and NGC 2064 is to the southwest, left of M78.

M78 lies at a distance of 1,600 light-years. It has an apparent size of 8 x 6 arcminutes and a real size of 5 light-years in space.

M78 was discovered by Pierre Méchain in 1780 and included as the 78th object in Charles Messier's catalog.

North is to the right in the above image.

M78 Catalogs: M78, NGC 2068 Object Type: Reflection Nebula Magnitude: 8.3b Size: 8' x 6' Constellation: Orion Image Field Centered At: RA: 05h 46m 43s Dec: +00° 02' 16"