From the June 2018 issue

Demystifying Messier 24

M24 is often misidentified as NGC 6603, but don’t let that stop you from seeking out this superb nebulosity.
By | Published: June 27, 2018 | Last updated on May 18, 2023

In the summer of 1764, the French comet hunter Charles Messier came upon a nebulous object “near the extremity of the bow of Sagittarius, in the Milky Way.” He went on to describe it as “a considerable nebulosity, of about one degree and a half extension: In that nebulosity there are several stars of different magnitudes; the light which is between these stars is divided in several parts.” It was recorded as the 24th entry in his catalog of nebulous objects.

Messier 24 (M24), visible to the unaided eye and three Full Moon diameters in length, was one of the last members of the Messier catalog that I officially notched. Why? It all has to do with resources that misidentified it as NGC 6603.

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