42 Orionis, also known as c Orionis or c Ori, is a triple star system in the constellation Orion. Its apparent magnitude is 4.59 and it is approximately 900 light years away based on parallax.
The primary star, Aa, has one spectroscopic companion Ab of magnitude 6.3 and separation 0.16", and a more distant companion B of 7.5 magnitude at 1.6" separation. Vizier catalog entry Preliminary results published in 2026 give an orbtal period of 69.2 years, an eccentricity of 0.23 and an inclination of 28.1° for the inner companion.
42 Orionis is surrounded by NGC 1977 one of a smaller fainter group of named nebulae just north of the Orion Nebula. 42 Ori is the star which excites and illuminates NGC 1977.
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