M12 (also known as NGC 6218) is a globular cluster in the constellation Ophiuchus. It was discovered by Charles Messier on May 30, 1764.
Located roughly 3° from the cluster M10, M12 is about 16,000 light-years distant and has a spatial diameter of ~75 light-years. The brightest stars of M12 are of 12th magnitude. It is rather loosely packed for a globular and M12 was once thought to be a tightly concentrated open cluster.
Images by Andrew Wilson
