M 17By astrored / November 6, 2023 M16 . . Index . . M18 Messier 17 M 17 (NGC 6618) Diffuse Nebula in Sagittarius. Omega, Swan, Horseshoe, or Lobster Nebula RA=18 20.8, Dec=-16 11. 7.0 mag, dist=5 kly. M17 page; DSSM page Hartmut Frommert ([email protected]) Christine Kronberg ([email protected]) Last Modification: 7 Apr 1998, 22:14 MET