Scientists Baffled by Sudden Brightness of Our Galaxy's Supermassive Black Hole

This story is part of Treehugger's news archive. Learn more about our news archiving process or read our latest news.
Gas and dust typically make up the accretion disk surrounding a black hole. HelloRF Zcool/Shutterstock

You never want to wonder what's eating a black hole.

In fact, moodiness is the last thing you want from a light-bending, time-sucking void.

But something seems to have gotten Sagittarius A* all fired up.

And, since it's the supermassive black hole at the heart of the Milky Way, it's a little hard to ignore.

Their research, revealed in Cornell University’s arXiv, suggests Sagittarius A* is flashing 75 times brighter than it has since monitoring began more than 20 years ago.

Back in May, astronomer Tuan Do from the University of California just happened to be peering at the heart of the galaxy from Hawaii's Keck Observatory, according to New Scientist.

He spotted something particularly bright. At first, Do assumed it was a star. Then he realized he was being flashed by the Milky Way's supermassive black-hole-in-residence.

"It was strange because I had never seen the black hole that bright before," Do tells New Scientist.

And how, you may ask, does something called a black hole twinkle? All that frantic hoovering of dust and gas generates a lot of heat and under a telescope's ultraviolet eye, it appears to flicker. Think of it as a little stardust left around the mouth — or in this case, the accretion disk — of a messy eater.

Black holes have no time for napkins.

The twin telescopes of the Keck Observatory in Hawaii
Hawaii's Keck Observatory features twin telescopes that are sensitive to radio and ultraviolet wavelengths. Abbie Warnock-Matthews/Shutterstock

The unprecedented flash from Sagittarius A*, however, suggests the cosmic carnivore may have gobbled up a very spicy celestial meatball.

"Maybe more gas is falling into the black hole and that leads to higher amounts of accretion, which leads to it being brighter," Do adds in New Scientist.

There's also a chance the black hole finally got around to eating a gaseous object identified as G2, which was found to be approaching Sagittarius A* in 2014.

But frankly, scientists don't understand why our black hole has suddenly grown so bright. Do and his team are hoping information from other telescopes can help solve the mystery.

One thing we do know is there's no chance Sagittarius A* is on the move. These chasms in space and time don't wander the galaxy looking for snacks. In fact, Sagittarius A* has been sitting at the same buffet table in the heart of the galaxy for billions of years.

But, like anyone who eats non-stop while being parked on their posteriors, black holes will gain mass — and expand in diameter.

Most estimates peg the diameter of Sagittarius A* at around 14 million miles wide, with a mass of 3.6 million suns. That qualifies it, in astronomical terms, as supermassive — but not nearly enough for a membership card to the ultramassive black hole club.

That's for the likes of the downright beastly Holm 15A*.

In any case, with Sagittarius A* some 25,640 light-years from Earth, we're not even close to being folded into its expanding girth.

Unless, of course, you consider that a black hole not only doesn't care for napkins, but also the rules of time and space.

We simply don't know what these cosmic enigmas are capable of. Perhaps, as renowned astrophysicist Michio Kaku once suggested, a black hole could literally tear the universe a new one.

"If space is a fabric, then of course fabrics can have ripples, which we have now seen directly. But fabrics can also rip. Then the question is, what happens when the fabric of space and time is ripped by a black hole?" he told the Economic Times earlier this year.

Let's just hope it was a spicy meatball.