The Omega, Swan, Horseshoe, or Lobster Nebula

M17 (in the Messier Catalogue) or NGC 6618 (in the New General Catalogue), is a Hydrogen II region nebula containing an open star cluster in the constellation of Sagittarius.

M17’s many names include the Omega Nebula, the Swan Nebula, the Horseshoe Nebula, the Lobster Nebula, and the Checkmark Nebula.

The Omega Nebula M17
M17, the Omega Nebula, captured by the Wide Field Imager on the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory in Chile. Image Credit ESO, 2015. Via (Click to expand)
Location of M16 Eagle Nebula
Locating M17, the Omega Nebula, in the constellation of Sagittarius from the ‘teapot’ asterism


M17 can only just be distinguished with the unaided eye, under the best viewing conditions, and is located just south of the Eagle Nebula and close to the Trifid Nebula (M20) and the Lagoon Nebula (M8).

The equatorial coordinates of the M17 are:
Right Ascension: 18h 20m 26s, Declination: −16° 10′ 36″

To find M17’s current position in the sky from your location, visit our Night Sky Simulator.

Astronomy, Cosmology, Space and Astrophysics