M20 - Trifid NEbula

M20 also called The Trifid Nebula is an extrordinary H II region located in Sagittarius. It was discovered by Charles Messier on June 5, 1764. The object is an unusual combination of an open cluster of stars; an emission nebula ( redish), a reflection nebula (blueish) and a dark nebula tha 'gaps' within the emission nebula that cause the trifurcated appearance. The Trifid Nebula is a star-forming region in the Scutum spiral arm of the Milky Way. The most massive star that has formed in this region is HD 164492A, an O7.5III star with a mass more than 20 times the mass of the Sun. This star is surrounded by a cluster of approximately 3100 young stars. [following wiki]