[9] In a 10 in (25 cm) scope, the granular core shows a diameter of 3′ (arcminutes) surrounded by a 10′ halo of stars.

[8] M12 is roughly 3°[9] northwest from the cluster M10 and 5.6° east southeast from star Lambda Ophiuchi.

[10] With a Shapley-Sawyer rating of IX,[1] it is rather loosely packed for a globular and was once thought to be a tightly concentrated open cluster.

[11] A study published in 2006 concluded that this cluster has an unusually low number of low-mass stars.

The authors surmise that they were stripped from the cluster by passage through the relatively matter-rich plane of the Milky Way.