Two studies support the suspicion that our galaxy’s black hole had one or more outbursts a few million years ago.
Black holes are among the weirdest things in astronomy. Predicted by Einstein’s theory of general relativity, these objects are so massive and compact that nothing, not even light, can escape. Since their prediction from theory, stellar-mass black holes have been found scattered throughout the Milky Way and supermassive black holes containing millions to billions of times the mass of the Sun have been found inhabiting the Milky Way’s center and the cores of most large galaxies. Some are dark; others blaze their way out of quiescence as they guzzle gas from their surroundings — we see these as X-ray sources and brilliant quasars. Peruse the stories below to read about the latest observations and theory.