Deep Sky Stacker
Photoshop CS5

M13, The Great Hercules Globular Star Cluster, is the largest (apparent) globular cluster in our sky. A jewel among globulars in our galaxy, it shines like diamonds! It is 22,000 light-years away. Globular clusters are millions of stars bound together in a sphere by gravitational forces. Look closely above it and you will see a 15-th magnitude active galaxy called IC (indexed Catalog) 4617 that got caught in the frame! This is a 2-hour exposure.