Black Hole Kicks Star Out of Milky Way

By Sarah Basford on at

Astronomers have uncovered a star leaving the galaxy at an extremely fast pace. They also found out why. Turns out, it was unceremoniously booted out by The Milky Way's supermassive black hole.

The star, called S5-HVS1, was found to be travelling at around six million kilometres per hour, or 1,700 kilometres per second, BBC Science Focus reports.

The astronomers, from Carnegie Mellon University and University of Oxford, came across the discovery during a Southern Stellar Stream Spectroscopic Survey. "The velocity of the discovered star is so high that it will inevitably leave the Galaxy and never return," Douglas Boubert, a co-author on the paper, said.

S5-HVS1's origins were traced back to the middle of The Milky Way where Sagittarius A*, a mean-looking supermassive black hole, is situated. It's about four million times the mass of our sun, according to NASA, so it's certainly a big guy.

"We think the black hole ejected the star with a speed of thousands of kilometres per second about five million years ago," the star's discoverer, Sergey Koposov, said. "This ejection happened at the time when humanity’s ancestors were just learning to walk on two feet."

It's believed the star got too close to Sagittarius A* and it did what black holes tend to do, absorbed it and ejected that straying star the hell outta there. Now, five million years or so after that drama, S5-HVS1 has been spotted in the Grus constellation, around 29,000 light years from Earth.

It was reportedly spotted by the Anglo-Australian Telescope (AAT) at the Siding Spring Observatory near Coonabarabran in New South Wales.

Featured image: Getty


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