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NASA’s Hubble Space Telescope has determined
the size of the largest icy comet nucleus

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ever found.

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And, it’s big!

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With a diameter of approximately 80 miles
across, it’s about 50 times larger than

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typical comets.

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Its 500-trillion-ton mass is a hundred thousand
times greater than the average comet.

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The challenge was distinguishing the solid
nucleus from the huge dusty coma enveloping

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it.

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The comet is so far away that its nucleus
is too small for Hubble to resolve.

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Instead, Hubble found a bright spike of light
at the nucleus’ location.

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Astronomers made a computer model of the surrounding
coma and adjusted it to fit the Hubble images.

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Then, the glow of the coma was subtracted
leaving behind the starlike nucleus, size

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was then estimated from it’s brightness.

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The behemoth comet is barreling this way at
22,000 miles per hour.

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But don’t worry.

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It won’t get any closer than roughly 1 billion
miles away from the Sun, slightly farther

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out than Saturn.