Four billion light years away, a galaxy is ejecting (or, was ejecting, four billion years ago) its own black hole, according to scientists' interpretation of new data from some of the world's most advanced telescopes. The galaxy, CID-42, is believed to be the product of a collision between two galaxies. In the wake of that collision, gravitational waves are propelling the black hole out of the galaxy at speeds of several million miles per hour. The ejected black hole is a massive X-ray source, which NASA's Chandra space telescope measured and captured in the inset above.
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