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Here's what you need
to know about astrobiology.

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How did life begin on Earth?

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Does life exist beyond Earth?

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How do we search for it?

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These are the really tough questions

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astrobiologists want to answer.

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But it's not easy.

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So far, we have one great example of life:

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Earth.

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But does it also exist elsewhere?

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On Earth, extremophiles (life that loves
extreme environments like Antarctica)

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tell us the limits to life,

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hinting at where it might exist elsewhere
in our solar system.

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Life on other planets could exist
in ways we couldn't possibly imagine.

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And if it does,
we might not know what we're looking at.

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So, we start by looking for
life as we know it.

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So when NASA scientists are searching
for exoplanets like Earth,

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they look for gases
or molecules like oxygen

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in exoplanets' atmospheres.

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Closer to home NASA is also
searching for signs of life on:

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Mars, Enceladus, Europa, Titan.

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Back home

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we study the great diversity of life
across our own planet.

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From the craziest,
wackiest corners of Earth

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to lifeforms that existed
billions of years ago.

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Helping inform us as we search
for life in the cosmos.

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In short, astrobiology is trying to answer
the very big question:

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Are we alone?

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And that's what you need to know
about astrobiology.