Messier 24 — Star Cloud in Sagittarius

M24, the Small Sagittarius Star Cloud, is not a true star cluster but rather a dense section of the Milky Way visible through a gap in the interstellar dust clouds. Located about 10,000 light-years from Earth in Sagittarius, this star cloud spans about 600 light-years in length and covers an area of about 2 degrees by 1 degree on the sky. It contains millions of stars and is one of the densest concentrations of individual stars visible in binoculars. Within M24 lies the small open cluster NGC 6603 and the dark nebula Barnard 92.

Located in the heart of the Sagittarius Milky Way, roughly midway between M18 and M25. At magnitude 4.6, it is easily visible to the naked eye as a noticeably bright patch in the Milky Way. Binoculars give the best view, revealing an astonishing field packed with countless faint stars. A wide-field telescope at low power (25-40x) shows the star cloud nicely, but the full extent is best appreciated with binoculars or the naked eye. Look for the dark nebula Barnard 92 as a conspicuous dark spot within the star cloud. Best from July through September.

Included in Messier's catalog in 1764. It is unique among Messier objects as it is not a discrete deep-sky object but a patch of the Milky Way itself. Some catalogs consider NGC 6603, the small cluster embedded in M24, to be the true Messier object, but Messier's original description clearly refers to the large star cloud.