M 12

Messier 12 or M 12 (also designated NGC 6218) is a globular cluster in the constellation of Ophiuchus. It was discovered by the French astronomer Charles Messier on May 30, 1764, who described it as a "nebula without stars".

Located roughly 3° in the sky from the cluster M10 and 5.6° from the star Lambda Ophiuchi, M12 is about 15,700 light-years (4,800 parsecs) from Earth and has a spatial diameter of about 75 light-years. The brightest stars of M12 are of 12th magnitude. With a Shapley-Sawyer rating of IX, it is rather loosely packed for a globular and was once thought to be a tightly concentrated open cluster. Thirteen variable stars have been recorded in this cluster. M12 is approaching us at a velocity of 16 km/s.

R = 11 * 400 sec. bin1, G = 11 * 460 sec. bin1, B = 11 * 560 sec. bin1.

PixInsight 1.8, Photoshop CC