1280px-A_simulation_of_how_a_gas_cloud_that_has_been_observed_approaching_the_supermassive_black_hole_at_the_centre_of_the_galaxy — ESO/MPE/Marc Schartmann

Artist’s impression of the disruption of a gas cloud as it passes close to Sgr A*, the supermassive black hole at the center of our galaxy.

Flares from the Milky Way’s Supermassive Black Hole

"Sgr A*, the 4.6-million-solar-mass black hole that lies at the center of the Milky Way, is normally a fairly quiet beast. The black hole slowly feeds on accreting material in the galactic center — but this food source is sparse, and Sgr A*’s accretion doesn’t produce anything like the fireworks we associate with supermassive black holes in active galaxies.

In May 2019, however, Sgr A* suddenly became substantially more active than usual, producing an unprecedented bright, near-infrared flare that lasted roughly 2.5 hours. This flare was more than 100 times brighter than the typical emission from Sgr A*’s casual accretion, and more than twice as bright as the brightest flare we’ve ever measured from our neighborhood monster.

The May 2019 flare marked the start of prolonged increased activity — an unusual number of strong flares that continued at least throughout 2019 (currently analyzed data extends only to the end of that year). What caused Sgr A* to wake up? And do we expect more flaring ahead? A new study by Lena Murchikova (Institute for Advanced Study) explores the options."