WEBVTT

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(SCIENCE TREK MUSIC)

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JOAN CARTAN-HANSEN, HOST:
Scientists have several

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different ways to find an
exoplanet.

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One is called radial velocity.

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Orbiting planets cause a change
in the color of the

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light of a star.

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Astronomers call it a wobble.

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Another method is
called a transit.

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When a planet passed between
the star and the observer, the

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light of the star dims a
tiny amount.

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That change in light indicates a
possible exoplanet.

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Astronomers can also take
pictures of an exoplanet by

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blocking out the glare of the
star it orbits.

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That's called direct imaging.

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Then there's gravitational
microlensing.

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Light from a distant star get
bent and focused by gravity as

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an exoplanet passes between that
star and Earth.

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And finally, astronomers look
for very tiny or minuscule

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movements of stars in relation
to other nearby stars.

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The orbit of a planet can cause
its star to wobble in its orbit.

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Exoplanets are very far away and
difficult to spot, but

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scientists are working hard to
find them.

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For more information about
exoplanets, check out the

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Science Trek website.

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You'll find it at
ScienceTrek.org.