Astronomers have for the first time measured the motion of a small black hole and a companion star speeding through our galactic neighborhood. The black hole and the star that it's slowly devouring travel together on a looping path that ultimately will take them toward the outer reaches of our galaxy.
In the Sept. 13 Nature, researchers argue that the black hole, which is the compact remains of a massive star, was ejected from a star cluster. Ever since, it has been wandering the galaxy along with its stellar companion, the scientists propose.
Known as XTE J1118+480, the duo was discovered last year by NASA's Rossi X-ray Timing Explorer satellite. Studies of its radio emissions reveal that the black hole-star combo qualifies as a miniature version of a quasar.