Nebula M 78

Reflection nebula M 78 (NGC 2068) in the constellation Orion. It is located in the Orion Cloud (Orion B molecular cloud), at a distance of 1,350–1,600 light-years from Earth. Its diameter is 3–5 light-years, with an apparent magnitude of 8.3m. The nebula's blue color is due to the color of its brightest stars and Rayleigh scattering of light. Inside M 78 is a cluster of 192 stars with a total mass of 113 solar masses. The brightest stars are HD 38563A and HD 38563B (spectral class B). In the upper part of the photo, above M 78, is the nebula NGC 2071, while around M 78 are NGC 2064 and NGC 2067.

The nebula was discovered by Pierre Méchain in 1780 and cataloged by Charles Messier as number 78. The best time for observation is January–February. Through binoculars (50 mm), it appears as a faint patch; through a telescope (from 120 mm), its structure and neighboring nebulae become visible.

About 300,000 years ago, M 78 collided with NGC 2071, triggering a burst of star formation.