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ASHWIN: I think what the Mars Curiosity rover is doing is answering one of the most important
questions to humankind.
Are we alone in this universe?
Can we never really lose sight of how important it is to ask those questions as a civilization.
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ASHWIN: We're ultimately searching for life on Mars.
The possibility if there ever was life on another place in the universe besides Earth
and Curiosity takes us one step towards that by trying to figure out if Mars ever could
have supported life.
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There are a few different places in our solar system where life could have evolved other
than Earth.
Mars has always been a fascinating possibility because its so close to Earth.
The temperature range is similar to Earth.
It gets above the freezing point, making liquid water possible.
We've gone there so many times now and we'll continue to do so because it's so much closer
than the further moons that maybe are targets for possibility for life.
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I think maybe the most straightforward model of life on Mars would be that it evolved differently
than Earth.
That Mars probably had conditions that were more friendly to life before Earth did even
and so if life took hold on Earth, then spread so much then why didn't it also do that on
Mars.
Another possibility that gets more interesting is that life was transferred to early Earth
to early Mars or maybe early Mars to early Earth and life is continually being spread
around the solar system as asteroids and comets and meteors transfer little particles from
one planet to another.
And of course the other possibility is sort of the null hypothesis that life doesn't exist
on Mars.
That Mars is a sterile planet and that's y'know equally interesting scientifically, but probably
a little less exciting y'know for other reasons.
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We're going to an ancient site on Mars where there's a huge stack of layered rock in this
mountain we call Mount Sharp that we've landed next to and this mountain is the largest stack
of layered rock we know of in the solar system.
Geologists get really excited with layered rock because it's a record of time just like
the Grand Canyon on Earth so our plan y'know has always been after picking this landing
site to drive over to Mount Sharp and just start climbing up the foothills. and take
measurements layer by layer determining from all the different instruments we have whether
any of those time periods in early Mars history that are now trapped as rocks at Mount Sharp
could have ever supported life.
In the distant past, there's all this geologic evidence of rivers, maybe even lakes or oceans
on Mars and that is really a fascinating thing to explore.
This is a planet that's undergone a huge climate change, we think.
Y'know, much more than the relatively small but important climate changes that are occurring
on Earth today.
We probably have gone on Mars from almost an Earth-like world with flowing water and
streams and rivers and precipitation to something that is a planetary wide just dry barren desert.
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I think what's so exciting for the science team here is that so far, y'know, after a
few tens of days on the surface, it's still a young mission.
Everything we've seen from our eyes on the surface of Mars has indicated that this landing
site is exactly what we hoped for.
After this mission, I hope Mars will no longer be an exotic place to people.
It won't be this alien planet like in the science fiction movies.
It'll be an Earth-like planet.
We will be driving around environments that look just like deserts on Earth and that's
really the whole point.
Mars is our neighbor planet.
It has the same geology, the same physics, the same atmospheric processes than Earth
and if all that's so similar than why isn't there life on Mars?