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Though an estimated 100 million black holes
roam our Milky Way galaxy, these objects are

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invisible and so very difficult to detect.

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Astronomers now believe they may have precisely
measured the mass of an isolated black hole

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for the first time.

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After six years of observations, NASA’s
Hubble Space Telescope found evidence for

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a lone black hole about 5,000 light-years
away wandering through interstellar space.

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Black holes roaming our galaxy are born from
rare, monstrous stars, less than one-thousandth

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of the galaxy’s stellar population, that
are many times more massive than our Sun.

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These stars die in supernova explosions – their
cores crushed by the star’s own gravity

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into a black hole.

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Because the detonation is asymmetrical, the
black hole may get a kick, sending it careening

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through our galaxy.

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Hubble detected the magnified and deflected
light from a star lined up exactly behind

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the potential black hole, as its intense gravity
warps space itself.

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The measurements indicate the black hole weighs
seven solar masses, and is traveling through

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space at 100,000 miles per hour!

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But don’t worry, there’s a lot of space
between Earth and this roaming black hole!