Two supermassive black holes, each of them more than a million times lighter than our sun.
Thankfully, the two black holes are both about 2.5 billion light-years The Astrophysical Journal Letters on Wednesday, so it will take long for astronomers to detect the cosmic waves given off by the collision.
When the black holes reach the final days of their fated approach, they will give off gravitational waves a million times stronger than those that were first discovered at LIGO, Flatiron Institute for Computational Astrophysics scientist Chiara Mingarelli explained in a Princeton University press release.
"Supermassive black hole binaries produce the loudest gravitational waves in the universe," she said.
Based on the location of other known supermassive black holes, the scientists expect to pick up the waves given off by other collisions within the next five years, via the press release. If they do not, it'll lend evidence to the so-called "final parsec problem," which would suppose that supermassive black holes never actually collide. Instead, it holds, they just go on endless spiral as soon as they reach a one-parsec, or about light-year distance from each other.
"It's a major embarrassment for astronomy that we do not know if supermassive." black holes merge, "Princeton astrophysicist Jenny Greene said in the press release.
Models predict that the final parsec problem is insurmountable unless three or more supermassive black holes all merge together. If that's true, then the astronomers do not want to detect any of those thunderous gravitational waves.
But if the astronomers do not pick up new waves in the next few years, they'll collide with one another
READ MORE: Astronomers have discovered a distant pair of titanic black holes on a collision course. Princeton University Newsroom ]
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