Even in this impressively sharp image, individual stars are difficult to distinguished in the densely packed core, but colors are apparent for the bright stars on the cluster's outskirts.
M3's many cool "red" giant stars take on a yellowish cast, while hotter giants and pulsating variable stars look light blue.
A closer look at the deep telescopic view also reveals a host of background galaxies.
Itself about 200 light-years across, the giant star cluster is a relatively bright, easy target for binoculars in the northern constellation Canes Venatici, The Hunting Dogs, and not far from Arcturus.
