Black Holes Bound to Merge Two supermassive black holes have
been found to be spiraling toward a merger, astronomers said
today. The collision will create a single super-supermassive
black hole capable of swallowing material equal to billions of
stars, the researchers said. Mergers between black holes are
thought to be one way they grow. A handful of similar setups
have been observed in which black holes appear inevitably on a
merger course. This pair, at the center of a galaxy cluster
called Abell 400, was known to be close but their fate hadn't
been determined. "The question was: Is this pair of supermassive
black holes an old married couple, or just strangers passing in
the night?" said Craig Sarazin of the University of Virginia.
"We now know that they are coupled, but more like the mating of
black widow spiders. One of the black holes invariably will eat
the other." Black holes can't be seen. Their presence is
inferred by their gravitational effects on their surroundings
and by radiation from near the bl