WEBVTT

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(MUSIC)

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JOAN CARTAN-HANSEN, HOST:

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The first astronomers observed

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comets by watching the night

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sky.

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From the ground, they identified

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about 900 comets from 1761 to

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1995.

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But as it turns out, human

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scientists are no match for the

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best comet hunter in space.

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That's the Solar and

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Heliospheric Observatory, better

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known as "SOHO."

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It was originally designed to

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study the sun, but scientists

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soon realized it was really good

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at finding comets.

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So far, it's found more than

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3000.

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But most of the comets its finds

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disintegrate.

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SOHO finds comets that pass very

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close to the sun.

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And those comets just can't

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handle the intense sunlight.

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So, they're destroyed.

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Astronomers think most of these

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comets are fragments of a much

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bigger comet that broke apart

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thousands of years ago.

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Scientists can learn a lot from

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these dying comets.

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Their tails are pushed around by

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the sun's magnetic fields.

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So, watching these tails move

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can tell researchers more about

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how the sun works.

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For more information about

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asteroids and comets, check out

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the Science Trek website.

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You'll find it at

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ScienceTrek.org