Messier 18 is a small, loose, sparse open cluster in Sagittarius located halfway between M17 and M24.

M18 shines at magnitude 6.9 and has an apparent diameter of 7 arcminutes. It is located at a distance of 4,900 light-years away. At that distance its true size would be 15 light-years in diameter.

It contains a dozen magnitude 8 to 10 stars, most of which are hot young B-type stars. The cluster is estimated to be only 32 million years old.

M18 was discovered by Charles Messier in 1764.

North is to the top in the above image.

Messier 18 Catalogs: M18, NGC 6613 Object Type: Open Cluster Magnitude: 6.9v Size: 7' Constellation: Sagittarius Image Field Centered At: RA: 18h 20m 42s Dec: -17° 07' 28"