X-Ray echo suggests our galaxy was "active" (quasar-like) just 200 years ago - Nature
X-Ray echo suggests our galaxy was "active" (quasar-like) just 200 years ago - Nature
A study reports the measurement of the polarization degree and angle of X-rays from Sagittarius A* reflected off a nearby cloud, indicating an X-ray flare about 200 years ago.
cross-posted from: https://lemmy.sdf.org/post/659261
Well, from the perspective of Earth. Obviously there's a big delay on the way here, which is kind of the entire idea of the technique used.
Plus, without reading the paper I'm not sure what "briefly" means. Even if it was a short spurt this is crazy, though.
So for idiots like me, what does it mean!?
So Sgr A* is the supermassive black hole in the center of our galaxy. It's pretty quiet right now, it's hard to even see.
Quasars are the most energetic phenomena in the sky. They're galaxies with a supermassive black hole that is devouring tons of stuff and raising absolute hell in the process.
This paper shows evidence that when Napoleon was marching across Europe - just an instant ago in cosmic terms - we lived in something not quite a quasar, but much more violent than the galaxy we measure today. If you had the right sort of telescope you could have seen we were belching massive amounts of radiation out into the wider cosmos.