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This is such an awesome experience
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To get up close and personal with the curiosity rover
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I mean, this isn't the exact one that's on Mars, obviously
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but it's basically identical
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VOICEOVER: I'm here at the Jet Propulsion Lab in Pasadena, California
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I don't know how we got in here, Bill. It's amazing.
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VOICEOVER: This is the NASA center that's famous for building things like the Mars rover,
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space probes, and rescuing Matt Damon from the red planet
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DEREK: You guys must get pretty sick of answering questions about The Martian
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KEN: Yes.
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VOICEOVER: This is project scientist Ken Farley
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I spoke with him about life on Mars.
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He's one of many scientists working on the first NASA mission in 40 years
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designed specifically to look for life on another planet.
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It's called, Mars 2020.
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DEREK: If there were life on Mars, wouldn't we have found it by now?
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KEN: No. We would not have found it by now.
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DEREK: But we've been looking! There's been a number of missions like
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the Viking landers and like Curiosity, for example
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DEREK: Part of the problem is, we're not even sure what we're looking for.
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Life on Mars may have been completely different from life on Earth
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Recent missions, like the Curiosity and Exploration rovers, look for and found evidence of water,
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a key ingredient for life.
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SARAH: Follow the water, where was the water and when was the water
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and then looking for habitability, looking for places that could have supported life.
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Now we know enough about Mars to look for ancient life
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instead of anything on the surface of Mars today.
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DEREK: There's no life on the surface of Mars today?
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SARAH: Most likely, if there is life on Mars today, it would be underground, underneath the ice caps,
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in places that are very very hard to investigate with the sort of rovers and landers that we've sent so far
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DEREK: So we're talking, like, moles, groundhogs [LAUGHTER]
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SARAH: Well, microscopic, bacterial moles. No, not actual moles!
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We're looking for, we call them biosignatures.
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It's a pattern or a substance in the rocks that can only have been formed by life.
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VOICEOVER: To find those biosignatures, the 2020 rover is gonna need cutting edge technologies,
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developed here at JPL.
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But for definitive proof of life, they'll need drill samples.
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KEN: We need to take a core, that's about the size of a piece of chalk.
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We have to collect 37 tubes like this that will ultimately be laid on the surface of Mars
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for possible return in the future.
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VOICEOVER: Mars 2020 is different from past missions
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because now NASA will need to bring those samples back to Earth to test them for evidence of life.
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KEN: If they are brought back to Earth, we will be able to use all sorts of different kinds of techniques,
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many of which have not yet even been invented
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because nobody has been posed with this question.
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VOICEOVER: So, in order to find life, we'll have to return those samples from Mars,
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something that's never been done before,
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then test those samples with techniques that haven't even been invented yet.
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So I had to ask:
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DEREK: How good do you think your chances are, of finding life?
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KEN: Hmmm
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I'd say they're poorer than even just because I remain skeptical
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Regardless, we will learn about what the early history of the Solar System is like.
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And that's the same environment, the same Solar System, that earth was in when life was evolving.
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If you want to understand the origin of life, on Earth 'cause that's the only place we know life exists,
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the rocks that recorded that are all gone.
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DEREK: So in a way, looking at Mars is like looking at a version of Earth frozen in time
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right about when life would've sprung?
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KEN: That's, I think, the most exciting way to look at it.
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It's just unbelievable. The stuff that is happening here is just so far beyond anything else.
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What are you doing today?
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Are you sitting in your cubicle, are you working on your computer?
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Ok, these guys are working on a freaking machine, in outer space, on Mars that is trying to discover life.
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This is cool.
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That was one of my field pieces from the Netflix show "Bill Nye Saves the World".
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on which I am a correspondent.
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If you haven't seen it, you should check it out.
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But, obviously, because that show is for a broader audience, I don't get to go into the kinda crazy detail
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that I sometimes do on this channel.
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For example, this image is the first ever beamed back from the Martian surface.
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It was taken by the Soviet lander, Mars 3 on December 2, 1971.
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After becoming the first man-made object to make a soft landing on Mars
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that lander transmitted data back to earth for just 14.5 seconds before going quiet.
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And no one really knows what happened to it
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but it might have had something to do with the huge dust storm that was taking place at the time.
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Now, this is the first clear image sent back from the Martian surface.
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It was taken by the Viking One Lander on July 20th 1976.
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And one of the stated aims for that mission, was to try to find evidence of existing life on the Martian surface.
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And there was this experiment called the labeled release experiment
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where a scoop of Martian soil was taken
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and then a dilute solution of nutrients was added into that soil
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but, in those nutrients was the radioactive atom
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Carbon-14, the idea was if you tried
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to detect the gases around the soil
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if you detect some radioactive Carbon Dioxide
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you know that the nutrients were
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broken down by something in the soil
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presumably something that's living.
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what was remarkable about this experiment was
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that it got a positive result, there were a few other experiments trying to detect life in other ways
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and they failed to get a detection, but this one detected radioactive Carbon Dioxide
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and what's even more impressive was the Viking 2 Lander
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which tried the same experiments
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after the Viking 1 Lander, it also got
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the same positive result, so things were
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looking promising, but then about a week
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later they tried to rerun the experiment
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add a little bit more nutrients to the
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soil and see if you could get more CO₂, but they couldn't
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there was no additional CO₂ released, so based on these negative results and the negative
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results of the other experiments.
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Most scientists have concluded that there is no surviving life on the surface of Mars, today.
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so how is the CO₂ produced in the first place?
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Well, chemists suspect that very highly oxidizing chemicals, things like perchlorates, exist in the Martian
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soil and would have reacted with the nutrients producing the CO₂ to start with.
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But, once those chemicals are used up, well there's nothing for those
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nutrients to react with, and so we get no
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CO₂ the next time, the nutrients are introduced.
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this story highlights just how difficult searching for life is using only remote instruments.
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And that's why, for Mars 2020 they're going to
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create some rock samples that should be
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returned to earth, if only they can get
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the budget for another mission that will go back and pick them up.
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But the rover they're sending in 2020, will also have some new tools on board
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that will allow them to look at rocks in
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finer detail than ever before.
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One tool called PIXL, will use x-ray spectrometry to try to
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detect chemical elements with a spatial resolution that
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goes down to the size of a grain of salt.
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Now what they be looking for, are layered structures similar to stromatolite found here on earth.
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those are mineral deposits which get built up by billions and billions of-
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tiny organisms. - So you are not really looking for fossils or tiny little you know, microbial evidence.
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We are looking for the structures that they would have produced, layered structures.
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that's how we know about the oldest life on Earth, and so it's logical to think
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that's how we might find out about this old life on Mars.
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And the job of finding evidence of past or current life on Mars
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is made even more difficult by Planetary Protection,
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that's the principle whereby we should not introduce any life from
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Earth to these places where we're studying like Mars.
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and that's completely understandable, because I mean the worst discovery of life we could make on Mars
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would be life that we introduced there
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by our spacecraft...
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I mean certain organisms are really hardy,
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even in the vacuum of space and even when bombarded by radiation.
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But, due to this constraint, spacecraft must be strenuously
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sterilized and also, they're restricted from landing near sites where we think
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there may be liquid water.
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I'm really looking forward to the results of the Mars 2020 mission.
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and hopefully a later mission, where we actually go back and collect the samples that were placed there.
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But one thing that really struck me from my interview with Kim Farley was
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when he said that Mars is really like a
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time capsule of the rocks that Earth had
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when life evolved here.
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That's, a way I'd never really thought about it before,
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but of course because of plate tectonics and
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all the weathering that would have taken place on earth,
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we don't have the rock record from when life was first evolving on
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this planet, and that makes Mars
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a really good place to look, not only for new forms of life, but also for an
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understanding of how life on Earth, may have begun.