Messier Index/M78

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M78
Observation data: J2000.0 epoch
Type Reflection
Right ascension 05h 46.7m
Declination +00° 03′
Distance 1,600 ly
Apparent magnitude (V) 8.3
Apparent dimensions (V) 8′ × 6′
Constellation Orion
Physical characteristics
Radius 2
Absolute magnitude (V) -
Notable features Part of the Orion Complex
Other designations NGC 2068, Ced55u

The nebula Messier 78 (also known as M 78 or NGC 2068) is a w:reflection nebula in the w:constellation Orion. It was discovered by w:Pierre Méchain in w:1780 and included by w:Charles Messier in his catalog of w:comet-like objects that same year.

M78 is the brightest diffuse reflection nebula of a group of nebulae that include NGC 2064, NGC 2067 and NGC 2071. This group belongs to the w:Orion Molecular Cloud Complex and is about 1,600 w:light years distant from w:Earth. M78 is easily found in small w:telescopes as a hazy patch and involves two w:stars of 10th magnitude. These two stars, HD 38563A and HD 38563B, are responsible for making the cloud of dust in M78 visible by reflecting their light.

About 45 w:variable stars of the T Tauri type, young stars still in the process of formation as well as some 17 w:Herbig-Haro objects are known in M78.

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