A swarm of black holes may be lurking in our galaxy’s heart
Hundreds of black holes may lie at the center of our Milky Way galaxy, according to a new study. Such a tight swirl of black holes, which had been theorized for decades but never detected, bolsters current models of how galaxies evolve, scientists say.
Many galaxies, including our own, have one supermassive black hole at their core, which grows by slowly pulling in a host of smaller objects, including stars and entire star systems. Scientists have suspected that this core region may also contain numerous smaller black holes tightly orbiting the supermassive one, but they’ve lacked evidence of such a swarm—until now.
In the new study, Charles Hailey, an astrophysicist at Columbia University, and his colleagues scrutinized the past dozen years of data gathered by the Chandra X-ray Observatory, an orbiting craft whose instruments are designed to detect high-energy radiation emitted by the immensely hot material surrounding exploded stars and near black holes. When they looked at the region of space within about 12 light-years of our galaxy’s supermassive black hole, an object dubbed Sagittarius A*, they found hundreds of x-ray sources. And when they compared the x-ray emissions for those closest to Sagittarius A* with those a little farther away, they found big differences.