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Does Mars have the ingredients for life? Well,\h
let's find out from the latest observations from\h\h

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our Curiosity rover. Hi, I'm Jim Green, Chief\h
Scientist at NASA and this is Gravity Assist.\h\h

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On this season of Gravity Assist,\h
we're looking for life beyond Earth.\h

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I'm here with Dr. Jen Eigenbrode and she\h
is an astrobiologist at NASA's Goddard\h\h

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Space Flight Center, specializing in organic\h
chemistry, geology, and potential biology of\h\h

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Mars, and ocean environments. So today,\h
we're going to concentrate on what we know\h\h

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about the potential for life on the planet\h
Mars. Welcome, Jen to Gravity Assist.\h

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Thanks for having me, Jim. Happy to be here.
Well, you know, you're part of a fabulous\h\h

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team working on a spectacular instrument\h
on the Mars Curiosity rover called SAM,\h\h

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which is the Sample Analysis at Mars instrument.
Well, why are you so interested in the organic\h\h

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molecules, what about them\h
is that connection to life?\h

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When we look up at the red planet, it's red,\h
it looks like it's just rusty. And we found\h\h

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out so far is not really rusty, it's just dust\h
on the surface that's like that. And underneath,\h\h

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it's actually darker gray in a lot of\h
places. And that darker gray tells us\h\h

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there's a different chemistry that's been\h
preserved. When we started this mission,\h\h

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there were a lot of scientists who really doubt we\h
were going to find any organic molecules at all.\h

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And it was because we thought the\h
planet was rather quiet, not doing much\h\h

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old and rusty. But we're actually finding things.\h
And that means that if we're finding organic\h\h

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molecules in 3 billion year old rocks, that\h
they have been preserved over that time period.\h\h

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So the question is, do those organic molecules\h
tell us anything about whether life was there\h\h

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or not? Certain types of organic molecules\h
or collections of molecules are considered\h\h

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signatures of life, meaning, they're most likely\h
to be formed by life rather than other processes.\h\h

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Sorting through those and making sure that it's a\h
life process versus a non-life process is kind of\h\h

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challenging at times. But when there's evidence\h
of life, in our Earth sample, usually you find\h\h

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multiple lines of evidence for that life. The\h
fact that we found organic material in these\h\h

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ancient lake sediments, tells us that if we look\h
in the right place, perhaps we're going to find\h\h