M10 - Globular Cluster in Ophiuchus
From the author of Sizing Up The Universe
Click here for Hertzsprung-Russell diagram.
23:10 EDT Jul 11, 2015.
Starlight Express SXV-H9 on 10" RCOS at f/9.
L = 8 min, R = 6 min, G = 6 min, B = 6 min
(unguided 20-second subexposures).
Log stretch, Unsharp mask.