Elusive mid-sized black hole spotted at center of swallowed galaxy

WASHINGTON - Astronomers have scrutinized a cluster of stars that is the apparent remnant core of a relatively small galaxy that was swallowed by the sprawling Milky Way 8 to 10 billion years ago. What lurks at the center of this cluster has them excited.

The researchers said Wednesday the unusual motion of seven stars in this cluster provides compelling evidence for the presence of an elusive mid-sized black hol