Astronomers said Thursday that they had detected a third ripple in the fabric of space-time, a remnant of a cosmic crash of two black holes 3 billion years ago.

These invisible ripples, called gravitational waves and first theorized by Albert Einstein, first burst into science’s view to great fanfare in February 2016 after a new $1.1 billion international experiment went online.

Experiment spokesman David Shoemaker, a researcher at the Massachusetts Institute of Technology, said the latest discovery shows these waves can be anywhere in the sky and may be commonplace in the universe.

Two black holes, which most likely were originally far apart, eventually merged into a giant one — 49 times the size of the sun — sending an invisible wave rippling out. It traveled 3 billion light-years until hitting twin detectors in Louisiana and Washington.
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