Orion nebula

The Orion nebula, or Messier 42, M42, or NGC 1976, is a diffuse nebula. It is visible to the naked eye in the night sky. It is exceptionally bright because it has O-type stars at its core. They are the hottest and brightest stars. The nebula is south of Orion's Belt in the constellation of Orion.

M42 is 1,344 ± 20 light years away from us.^[1]^[2] It is the closest region of massive star formation to Earth. Big as it is, the Orion nebula is just part of an even larger star-forming area known as the Orion complex.

↑ Reid M.J. et al 2009. Trigonometric parallaxes of massive star forming regions: VI. Galactic structure, fundamental parameters and non-circular motions. Astrophysical Journal 700: 137. [1]
↑ Hirota, Tomoya et al 2007. Distance to Orion KL measured with VERA. Publications of the Astronomical Society of Japan 59 (5): 897–903. [2]

[1] Reid M.J. et al 2009. Trigonometric parallaxes of massive star forming regions: VI. Galactic structure, fundamental parameters and non-circular motions. Astrophysical Journal 700: 137. [1]

[2] Hirota, Tomoya et al 2007. Distance to Orion KL measured with VERA. Publications of the Astronomical Society of Japan 59 (5): 897–903. [2]

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