The Sagittarius Star Cloud (also known as Delle Caustiche, Messier 24, IC 4715) is a w:star cloud in the w:constellation of Sagittarius, approximately 600 w:light years wide, which was discovered by w:Charles Messier in 1764.
The stars, clusters and other objects comprising M24 are part of the Sagittarius or Sagittarius-Carina arms of the w:Milky Way galaxy. Messier described M24 as a "large nebulosity containing many stars" and gave its dimensions as being some 1.5° across, a description that fits the star cloud rather well. Some sources, improperly, identify M24 as the faint cluster w:NGC 6603.
M24 fills a space of significant volume to a depth of 10,000 to 16,000 w:light-years. This is the most dense concentration of individual stars visible using w:binoculars, with around 1,000 stars visible within a single w:field of view.