What is Omega Nebula?
[[File:VST_image_of_the_spectacular_star-forming_region_Messier_17_(Omega_Nebula).jpg|thumb|Omega Nebula]] The '''Omega Nebula''' (nicknamed the ''Swan Nebula'') is an [[H II region]] in the [[constellation]] of [[Sagittarius (constellation)|Sagittarius]]. It is about 5,500 [[light-year]]s away from [[Earth]]. It was discovered by [[Philippe Loys de Chéseaux]] in 1745.<ref>Nigel Henbest; Heather Couper, ''The Guide to the Galaxy'' (New York: Press Syndicate of the University of Cambridge, 1994), p. 209</ref> [[Charles Messier]] added it to his [[catalog]] as M17 on the night of 3 June 1764.<ref name=Thompson407> Robert Thompson; Barbara Thompson, ''Illustrated Guide to Astronomical Wonders: From Novice to Master Observer'' (Sebastopol, CA: Make:Books, 2007), p. 407</ref> M17 has more names than any other [[deep-sky object]]. In addition to the Omega Nebula and Swan Nebula, it is also called the Horseshoe Nebula, the Checkmark Nebula and the Lobster Nebula.<ref name=Thompson407/> Omega can be seen through binoculars or a small telescope.<ref>Philip S. Harrington; Edward Pascuzzi, ''Astronomy for All Ages: Discovering the Universe Through Activities for Children and Adults'' (Guilford, CT: Globe Pequot Press, 2000), p. 153</ref> == References == {{reflist}} {{Gum catalogue}} [[Category:Nebulae]] {{sci-stub}}