A new discovery by scientists could totally change how we understand our home galaxy.
A huge discovery by scientists could solve a mystery about the supermassive black hole at the center of the Milky Way that appears to be strangely quiet: researchers think that there was a “blowout bash” just 6 million years ago. The new study, published in the Astrophysical Journal recently, says that the black hole transitioned into hibernation with a bang, sending high-energy shockwaves that can still be seen by scientists today.
Researchers, who were trying to figure out why all the visible matter int he Milky Way adds up to less than their should be, were looking for this missing matter in the Milky Way when they came upon the shockwaves. The scientists think this missing matter, which encompasses up to 235 billion solar masses worth of material, could be made up in the thin shroud of gas that surrounds the Milky Way.
The scientists think this gas was blown out by a huge explosion from the quasar at the center of our galaxy just 6 million years ago, resulting in a big bubble of space without gas that is starving the black hole.
“We played a cosmic game of hide-and-seek. And we asked ourselves, where could the missing mass be hiding?” says lead author Fabrizio Nicastro, a research associate at the Harvard-Smithsonian Center for Astrophysics (CfA) and astrophysicist at the Italian National Institute of Astrophysics (INAF). “We analyzed archival X-ray observations from the XMM-Newton spacecraft and found that the missing mass is in the form of a million-degree gaseous fog permeating our galaxy. That fog absorbs X-rays from more distant background sources.”
“The different lines of evidence all tie together very well,” says Smithsonian co-author Martin Elvis (CfA). “This active phase lasted for 4 to 8 million years, which is reasonable for a quasar.”