Messier 78

Messier 78
Reflection nebula
Image of Messier 78 captured using the Wide Field Imager camera on the MPG/ESO 2.2-metre telescope at the La Silla Observatory.
Observation data: J2000.0 epoch
Right ascension05h 46m 46.7s
Declination+00° 00′ 50″
Distance1,350 ly (415 pcly
Apparent magnitude (V)8.3
Apparent dimensions (V)8′ × 6′
ConstellationOrion
Physical characteristics
Radius5 ly
Notable featuresPart of the Orion complex
DesignationsCed 55u, DG 80, IRAS 05442-0000, [KPS2012] MWSC 0664, NGC 2068

Messier 78 (also known as M78 or NGC 2068) is a reflection nebula in the constellation Orion. It is the brightest diffuse reflection nebula in a group that includes NGC 2064, NGC 2067, and NGC 2071, all part of the Orion B molecular cloud complex. Located approximately 1,350 light-years from Earth, M78 is visible in small telescopes as a hazy patch illuminated by two B-type stars, HD 38563 A and HD 38563 B, of 10th and 11th magnitude. It is a popular target for amateur astronomers, who have given it the common name Casper the Friendly Ghost Nebula.