‘Unprecedented’: Supermassive Black Hole at Our Galaxy’s Center Just Flashed Like Crazy

Our galaxy’s supermassive black hole is acting weirder than normal

Our galaxy’s supermassive black hole is acting weirder than normal

The supermassive black hole at the heart of the Milky Way, Sagittarius A*, is relatively quiet.

What made the black hole turn bright so suddenly?

While it is normal for the supermassive black hole to fluctuate slightly in brightness, the researchers found Sagittarius A*-which is four million times the mass of the sun-had gotten 75 times brighter than normal. That's the brightest we've ever seen Sgr A* in near-infrared wavelengths. "I was pretty surprised at first and then very excited", Do told the news site. 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*.

The galaxy, Holm 15A, sits around 700 million light-years away, making it somewhat hard to study in detail, but what scientists know for sure is that the black hole in its heart is the largest ever discovered.

But what? That's what astronomers are on a mission to find out.

Tuan and colleagues managed to catch a glimpse of the rare phenomena from the WM Keck Observatory in Hawaii while it was occurring and posted a timelapse of the observation on Twitter. The odd brightening took place on May 13, and the team managed to capture it in a timelapse, two hours condensed down to a few seconds. Black holes themselves don't emit any radiation that can be detected by our current instruments, but the stuff nearby does when the black hole's gravitational forces generate vast friction, in turn producing radiation. Normally, the brightness of Sgr A* flickers a bit like a candle, varying from minutes to hours. It's possible a large volume of matter fell into the black hole's gravity well, and that caused the flash.

Nearly 26,000 light years from Earth, Sagittarius A* - or Sgr A* - is typically fairly restrained as supermassive black holes go, but this past summer that has all been flipped. However, the objects and material close to them do-and changes to the black hole can excite matter nearby, allowing scientists to detect changes taking place. There's also a gas cloud called G2 that swing around Sagittarius A* in 2014. While the supermassive black hole itself isn't visible, its so-called electromagnetic counterpart can be tracked. There is a possibility this is a delayed reaction to that event. First, the aforementioned S0-2, which is in a long 16-year orbit of Sagittarius A*.

Researchers believe that the unusual "glow" may relate to gas clouds or stars which orbit the enormous black hole.

The only way to find out is having more data.

Other teams and telescopes, such as Spitzer, Swift, Chandra, and ALMA, have also been observing Sagittarius A*.

Luckily, there are plenty of sources for extra data to help fathom the cause of the change.

The paper has been accepted into The Astrophysical Journal Letters, and is available on arXiv.

"I'm eagerly awaiting their results", Do said.