As spring in the Northern Hemisphere begins to blend into summer, the night sky changes as well: the huge galaxy-rich fields of early spring skies begin to drift down towards the west, and the objects closer to the Milky Way become more prominent. The late spring and early summer sky is full of an interesting type of object: globular clusters, huge balls of stars held together by their own gravity, orbiting the entire Milky Way galaxy.

One of the first globular clusters to appear in spring is M3, third in Charles Messier's famous catalog of deep-sky objects. M3 is in Canes Venatici,the Hunting Dogs that perpetually chase Ursa Major around the sky. Like many of the spring Messier objects, M3 is in a fairly empty part of the sky. It has a magnitude of +6.2, making it just visible without a telescope under a dark sky. Observing details follow...