The first sleeping black hole has been found outside the Milky Way

for the first time, Researchers have discovered a sleeping black hole outside the Milky Way. Named VFTS 243, it is nine times the mass of our Sun and orbits a star in the Large Magellanic Cloud Galaxy. The discovery came after six years of observations with the European Southern Observatory’s (ESO) Very Large Telescope (VLT) in Chile.

“A needle in a haystack”

A black hole is considered “sleeping” because it does not emit high levels of X-rays., which is how these structures are naturally discovered. This type of black hole is theoretically expected, but has never been recognized. “We found a needle in a haystack,” said Tomer Schnarer, a researcher at the University of Amsterdam who led the study published in the journal Nature Astronomy.

Stellar-mass black holes form when massive stars reach the end of their lives and collapse under the influence of their own gravity. In a binary system, a system of two stars orbiting each other, this process leaves behind a black hole orbiting a star. “We’ve been searching for these binary black hole systems for more than two years,” said Julia Bodensteiner, co-author of the study and a researcher at ESO.

This discovery gives the team unique insight into the processes accompanying the formation of black holes. Astronomers believe that a stellar-mass black hole forms when the core of a massive dying star collapses, But whether or not this is accompanied by a supernova explosion remains to be seen.

“The star that formed the black hole VFTS 243 appears to have collapsed completely, with no sign of a previous explosion”Shinar explained. “Evidence for this ‘forward collapse’ scenario has emerged recently, but our study provides one of the most direct indications. This has huge implications for the origin of black hole mergers in the universe.”