Although astronomers estimate that the Milky Way Galaxy harbors between 100 million and 1 billion black holes, they have confirmed less than two dozen so far. Astronomy presented a census of these neighbors, including where in the galaxy each of them resides, in “Black holes in our backyard.” Researchers hope to expand this list — and their knowledge of these enigmatic objects — in the years ahead.
Black holes rank among the most mysterious and exotic objects in the universe. Each of these weird misfits, whose gravitational pull exceeds even light’s capacity to escape, distorts the space-time continuum that surrounds it. They give up their identity only when another object — a star or gas cloud, for example — comes too close. As the black hole’s gravity pulls in material, the gas becomes superheated and emits copious amounts of electromagnetic radiation.