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What Saturn's most mysterious moon could teach us about the origins of life

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    Picture a world
    with a variety of landforms.
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    It has a dense atmosphere
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    within which winds
    sweep across its surface
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    and rain falls.
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    It has mountains and plains,
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    rivers, lakes and seas,
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    sand dunes
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    and some impact craters.
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    Sounds like Earth, right?
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    This is Titan.
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    In August 1981,
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    Voyager 2 captured this image
    of Saturn's largest moon.
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    the Voyager missions have traveled
    farther than ever before,
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    making the Solar System and beyond
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    part of our geography.
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    But this image, this hazy moon
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    was a stark reminder
    of just how much mystery remained.
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    We learned an exponential amount
    as the Voyagers flew by it,
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    and yet we had no idea what lay beneath
    this atmospheric blanket.
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    Was there an icy surface with landforms
    like those of the other moons
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    that had been observed
    at Saturn and Jupiter?
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    Or perhaps simply a vast
    global ocean of liquid methane?
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    Shrouded by the obscuring haze,
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    Titan's surface was a huge
    outstanding mystery.
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    that Cassini-Huygens,
    an orbiter lander pair launched in 1997,
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    was designed to solve.
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    After arrival in 2004,
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    the early images Cassini sent back
    of Titan's surface
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    only heightened the allure.
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    It took months for us to understand
    what we were seeing on the surface,
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    to determine, for example,
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    that the dark stripes,
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    which were initially so unrecognizable
    that we referred to them as cat scratches,
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    were actually dunes made of organic sand.
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    Over the course of the 13 years
    that Cassini sent studying Saturn
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    and its rings and moons,
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    we had the privilege
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    of going from knowing almost nothing
    about the surface of Titan
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    to understanding its geology
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    the role the atmosphere plays
    in shaping its surface,
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    and even hints of what lies
    deep beneath that surface.
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    Indeed, Titan is one
    of several ocean worlds,
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    moons in the cold outer Solar System
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    beyond the orbits of Mars
    and the Asteroid Belt
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    with immense liquid water oceans
    beneath their surfaces.
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    Titan's interior ocean may have
    more than 10 times as much liquid water
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    as all of the Earth's rivers, lakes,
    seas and oceans combined.
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    And at Titan, there are also
    exotic lakes and seas
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    of liquid methane and ethane
    on the surface.
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    Ocean worlds are some of
    the most fascinating places
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    in the Solar System,
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    and we have only
    just begun to explore them.
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    This is Dragonfly.
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    At the Johns Hopkins
    Applied Physics Laboratory,
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    we're building this mission
    for NASA's new Frontiers program.
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    Scheduled to launch in 2026
    and reach Titan in 2034,
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    Dragonfly is a rotorcraft lander,
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    similar in size to the Mars rovers
    or about the size of a small car.
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    Titan's dense atmosphere,
    combined with its low gravity,
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    make it a great place to fly,
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    and that's exactly what Dragonfly
    is designed to do.
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    Technically an octocopter,
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    Dragonfly is a mobile laboratory
    that can fly from place to place
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    taking all of its scientific
    instruments with it.
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    Dragonfly will investigate Titan
    in a truly unique way,
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    studying details
    of its weather and geology
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    and even picking up samples
    from the surface
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    to learn what they're made of.
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    All told, Dragonfly will spend
    about three years exploring Titan,
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    measuring its detailed chemistry,
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    observing the atmosphere
    and how it interacts with the surface,
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    and even listening for earthquakes,
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    or technically titanquakes,
    in Titan's crust.
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    The Dragonfly team,
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    hundreds of people across
    North America and around the world,
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    is hard at work on
    the design for this mission,
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    developing the rotorcraft,
    its autonomous navigation system,
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    and its instrumentation,
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    all of which will need to work together
    to make science measurements
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    on the surface of Titan.
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    Dragonfly is the next step
    in our exploration
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    of this fascinating natural laboratory.
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    In flying by, Voyager hinted
    at the possibilities.
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    In orbiting Saturn for over a decade
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    and descending through Titan's atmosphere,
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    Cassini and Huygens pulled
    Titan's veil back a bit further.
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    Dragonfly will live the Titan environment,
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    where, so far, our only close-up view
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    is this image the Huygens probe
    took in January 2005.
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    In many ways, Titan is the closest
    known analogue we have to the early Earth,
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    the Earth before life developed here.
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    From Cassini-Huygens' measurements,
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    we know that the ingredients for life,
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    at least life as we know it,
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    have existed on Titan,
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    and Dragonfly will be fully immersed
    within this alien environment,
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    looking for compounds similar to those
    that might have supported
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    the development of life here on Earth
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    and teaching us about
    the habitability of other worlds.
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    Habitability is a fascinating concept.
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    What's necessary to make
    an environment suitable to host life,
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    whether life as we know it here on Earth,
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    or perhaps exotic life that has developed
    under very different conditions?
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    The possibility of life elsewhere
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    has inspired human imagination
    and exploration throughout history.
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    On a grand scale,
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    it's why the ocean worlds
    in the outer Solar System
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    have become such
    important targets for study.
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    It's the "what if"
    that drives human exploration.
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    We don't know how chemistry
    took the step to biology here on Earth,
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    but similar chemical processes
    may have happened on Titan,
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    where organic molecules
    have had the opportunity
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    to mix with liquid water at the surface.
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    Has organic synthesis progressed
    under these conditions?
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    And if so, how far?
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    We don't know, yet.
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    What we will learn from Dragonfly,
    this fundamentally human endeavor,
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    is tantalizing.
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    It's a search for building blocks,
    foundations, chemical steps
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    like those that ultimately
    led to life on Earth.
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    We're not sure exactly
    what we will find when we get to Titan,
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    but that's exactly why we're going.
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    In 1994, Carl Sagan wrote,
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    "On Titan, the molecules
    that have been raining down
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    like manna from heaven
    for the last four billion years
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    might still be there,
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    largely unaltered, deep frozen,
    awaiting the chemists from Earth."
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    We are those chemists.
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    Dragonfly is a search
    for greater understanding,
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    not just of Titan and the mysteries
    of our Solar System,
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    but of our own origins.
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    Thank you.
Title:
What Saturn's most mysterious moon could teach us about the origins of life
Speaker:
Elizabeth "Zibi" Turtle
Description:

more » « less
Video Language:
English
Team:
closed TED
Project:
TEDTalks
Duration:
07:06

English subtitles

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