Astronomers Spot Mysterious Flash From Our Galaxy's Supermassive Black Hole - Tue 13 Aug 14:33 GMT

It's usually very dim, but astronomers recently saw Sagittarius A* flare up -- in fact, it just got brighter than we've ever seen it.

  For instance, Sagittarius A* (pronounced “Sagittarius A Star”) in the center of our own Milky Way galaxy.

  Astronomers have detected many active galactic nuclei like quasars around the universe, but Sagittarius A* is on the quiet side despite being four million times more massive than the sun.

  However, it became apparent over the course of about two and a half hours that the source was variable and was, in fact, Sagittarius A*.

  At its peak, Sagittarius A* was 75 times brighter than usual in infrared.

  Scientists have been watching Sagittarius A* for decades, but no one was sure what to make of it for much of that time; it was just a strong X-ray source deep in the Milky Way.

  In the late 1990s and early 2000s, studies of objects near Sagittarius A* demonstrated it had a strong gravity explained best by a supermassive black hole.

  Today, the evidence for Sagittarius A* as the gravitational center of the Milky Way is quite solid.