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HUBBLE FINDS EVIDENCE OF
MID-SIZED BLACK HOLE

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Astronomers have found the best evidence yet
of a black hole of an elusive class
known as “intermediate mass.”

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This mid-sized black hole betrayed its existence by
tearing apart a wayward star that passed too close.

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About 50,000 times more massive than our Sun,
this black hole is smaller than supermassive black holes
that lie at the cores of large galaxies…

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…but it’s larger than stellar-mass black holes
formed by the collapse of a massive star.

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In 2006, satellites detected a powerful flare of X-rays,
but researchers weren’t sure if the source was
inside or outside our galaxy.

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Hubble was pointed at the X-ray source to
figure out its precise location.

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Hubble found that the X-rays emanated
from a distant, dense star cluster on
the outskirts of another galaxy…

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…the exact place astronomers would expect
to find a mid-sized black hole.

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Mid-sized black holes are a long-sought
“missing link” in black hole evolution.

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They’re very difficult to find because they’re
smaller and less active than supermassive black holes.

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Astronomers essentially have to catch one
red-handed in the act of gobbling up a star.
And this time, they did.

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[ INTENSE MUSIC ]