‘Visitor from a Strange Land’ – Star Ejected by Milky Way’s Supermassive Black Hole Now Traveling at over 3 Million MPH
Five million years ago the supermassive black hole at the center of our galaxy ejected a bright blue star – now, it's 29,000 light-years away, but not for long.
According to reports from Space.Com, an international team of astronomers led by Carnegie Mellon University research Sergey Koposov observed the star traveling ten times faster than any other star in the Milky Way. They published their research in the Monthly Notices of the Royal Astronomical Society.
The star – S5-HVS1 – is an A-type star like Sirius. These are the third-hottest types of stars. They emit blue light and have a mass approximately three times the size of our Sun (and the brightness of 80 Suns), with an average surface temperature range of 7,500 - 11,000 Kelvins (13,040-19340°F).
"High-velocity stars," as they are called, have only been discovered within the past twenty years, and scientists were able to trace this one back to its origin.
S5-HVS1 was originally part of a binary star system that fell into the maw of Sagittarius A, the supermassive black hole at the center of the Milky Way galaxy. One star was ripped apart by its gravitational pull. The other, S5-HVS1, was ejected, hurled into the abyss at speeds over 3 million miles per hour. "This is super exciting, as we have long suspected that black holes can eject stars with very high velocities. However, we never had an unambiguous association of such a fast star with the Galactic Center," lead author Sergey Koposov said in a statement.
It won't be around for long – S5-HVS1 has passed Earth and will continue screaming through the cosmos at a velocity several (several) times the speed of sound. "The velocity of the discovered star is so high that it will inevitably leave the Galaxy and never return," said Douglas Boubert, a coauthor of the study from the University of Oxford.