Omega Nebula

Omega Nebula
Emission nebula
H II region
VLT Survey Telescope image of the star-forming region Messier 17
Observation data: J2000 epoch
Right ascension18h 20m 26s[1]
Declination−16° 10′ 36″[1]
Distance5,000–6,000 ly
Apparent magnitude (V)6.0[1]
Apparent dimensions (V)11 arcmins
ConstellationSagittarius
Physical characteristics
Radius11 ly
DesignationsM17, Swan Nebula,[1] Sharpless 45, RCW 160, Gum 81
See also: Lists of nebulae

The Omega Nebula is an H II region in the constellation Sagittarius. It was discovered by Philippe Loys de Chéseaux in 1745. Charles Messier catalogued it in 1764. It is by some of the richest starfields of the Milky Way, figuring in the northern two-thirds of Sagittarius. This feature is also known as the Swan Nebula, Checkmark Nebula, Lobster Nebula, and the Horseshoe Nebula,[1][2] and catalogued as Messier 17 or M17 or NGC 6618.

  1. ^ a b c d e "NGC 6618". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 16 November 2006.
  2. ^ Cite error: The named reference psm1876 was invoked but never defined (see the help page).