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ROWE: Orbiting the magnificent
ringed planet, Saturn,
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are a series of
extraordinary moons.
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LANZA:
The closer that we look,
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the more that we see its moons
are like worlds of their own--
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00:00:19,172 --> 00:00:20,827
so dynamic,
so Earth-like.
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ROWE: Almost a billion miles
from the Sun,
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these icy worlds could be
home for Life 2.0.
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The moons of Saturn
offer possibly the best
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chance of finding
extraterrestrial life
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in our solar system.
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ROWE: With each new mission,
we get closer
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00:00:46,000 --> 00:00:49,482
to unraveling the mysteries of
Saturn's moons.
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[electricity sparking]
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[explosion blasts]
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ROWE:
October 2019.
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Astronomers discover
20 new moons
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orbiting the gas giant, Saturn.
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These tiny,
three-mile-wide objects
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bring the ringed planet's
moon count to over 80,
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the most of any planet
in our solar system.
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You hate to play favorites,
but I'm gonna say it--
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Saturn is my favorite
planetary system.
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It is unbelievably beautiful,
with this incredible system of
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rings and moons,
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and there's a lot of mystery
kind of all bound up in there.
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ROWE: The Voyager spacecraft
gave us our
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first close look at Saturn
and its rings.
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Two decades later,
Cassini got us even closer
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to many of Saturn's moons.
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There's Prometheus, Pandora,
and Atlas.
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Its largest moon, Titan,
is a moon that's shrouded
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in mystery.
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There's Mimas,
that's fairly small,
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and then Tethys and Dione
are a bit larger.
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00:02:25,172 --> 00:02:27,620
There are a pair of moons--
Janus and Epimetheus--
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that were perhaps
one moon in the past.
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Iapetus, half of it's
bright white.
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The other half of it is
sort of as
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dark as coal,
sort of yin and yang.
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Each of
the moons of Saturn
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had remarkable
stories to tell.
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ROWE: In 2005,
Cassini discovered that
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one moon's story was
particularly exciting.
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PLAIT:
Yeah, Enceladus.
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Enceladus is one of Saturn's
wee little moons.
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It's about 300 miles across--
for scale,
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it's roughly the size
of Colorado.
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ROWE: The spacecraft's
cameras spot plumes of
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water vapor shooting
out from Enceladus
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at 800 miles an hour.
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Three times as powerful than
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all the hot springs
in Yellowstone.
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RADENBAUGH: The discovery of
geysers gushing out of tiny,
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little Enceladus that should
have been cold and dead,
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completely changed our view of
what that moon exactly was.
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DURDA: It's alive.
That moon is alive.
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I'd like to be standing there
on the surface of Enceladus to
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see with the--
this water vapor
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and ice crystals booming
out of the surface
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at supersonic speeds.
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ROWE: Cassini's sensors
probe deep beneath
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the frozen surface
of Enceladus,
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detecting hints
of a rocky core
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00:04:06,103 --> 00:04:09,103
and something else
even more remarkable.
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Underneath that
thick layer of ice,
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there is liquid
water ocean.
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CHRISTIANSEN: The measurements
suggest his is a huge part of
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Enceladus's interior volume,
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about six miles deep,
because it was making Enceladus
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wobble in its orbit.
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00:04:26,896 --> 00:04:29,413
Imagine putting liquid inside
a ball and rolling it.
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You see the natural wobble of
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the ball as the liquid
sloshes around.
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ROWE: Giant liquid oceans
on an alien world,
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opening up exciting
new possibilities.
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Where you find water,
you could possibly find life.
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If you had asked me 20 years
ago where there might be life
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in the solar system
besides Earth,
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I think Saturn's moons would
have been the last place
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I would have picked.
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But against all odds,
it's looking like this tiny icy
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moon orbiting Saturn
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nearly a billion miles from
the Sun may be one of
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the best places
to look for life.
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ROWE:
July 2021.
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A new study reexamines
Cassini's plume data
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and finds huge quantities
of methane.
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This large amount can't be
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explained by just
geochemical processes.
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The methane might be from
primordial organic matter
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breaking down in
Enceladus's oceans,
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or even processes
we've never seen before.
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But it could be that
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living microorganisms helped
generate the methane,
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just like they do on Earth.
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Enceladus might actually look
a lot like early Earth in its
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00:06:00,793 --> 00:06:02,896
deepest oceans,
when life was first arising,
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because we know that there are
some chemical pathways that are
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likely occurring on Enceladus
that happened on Earth.
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ROWE: These chemical pathways
start with
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hot, hydrothermal vents
on Earth's
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cold sea floor, releasing
important life-giving chemicals
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into the oceans.
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Having hydrothermal vents
are a real
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boon to the evolution of life.
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PLAIT: These are cracks in
the Earth's crust, where
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hot material can then spew out
into the ocean.
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RADEBAUGH:
And that's the energy
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that life needs
to be able to form,
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and then water so everything
is present, and things
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are able to just grab all
these resources and energy
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and just start
to evolve.
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ROWE: On Earth, hydrothermal
vents produce methane,
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but only in small amounts.
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Microbial life
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living around the vents
makes the rest.
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Maybe microorganisms
do the same
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at the bottom of Enceladus's
deep oceans.
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Hydrothermal vents on
Enceladus could offer
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the perfect location
for chemistry
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becoming biochemistry
becoming life.
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ROWE: Hydrothermal vents
normally require
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heat from a hot core.
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So what's going on
inside Enceladus?
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This is an icy moon out there
in the cold outer solar system.
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Where is all this heat
coming from?
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ROWE: Cassini spotted
Enceladus's plumes
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shooting out
from parallel cracks
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00:07:54,379 --> 00:07:57,482
in the surface,
called tiger stripes.
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00:08:02,517 --> 00:08:06,000
The cracks are a clue to
the origin of the geysers
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and the energy that
powers them.
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We look to the orbit of
Enceladus itself.
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It's not in a perfectly
circular orbit
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around the planet.
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It's on a slightly elliptical
orbit, and that means that
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the tidal forces acting on
the moon change over time.
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00:08:22,482 --> 00:08:25,586
It's a little bit like
the forces on a rubber ball.
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When the moon is closer to
the planet, it's stretched out,
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and when the moon is
farther from the planet,
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it's relaxed back a little bit,
so you're gonna squeeze
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and deform and squish
the body of
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that moon over time, which is
gonna heat its interior.
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ROWE: The warm, rocky core
heats up the ocean,
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which both powers the geysers
as they burst
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through the surface
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and creates conditions that
could support life.
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DURDA: We see the energy source
kicking the water
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out of
the Enceladus subsurface.
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You combine that energy source
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and liquid water,
that harkens to putting
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us on the same path
that early life
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may have taken
here on the Earth.
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And if that's the case,
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there could be little beasties
swimming underneath the surface
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of one of Saturn's moons.
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ROWE: Saturn's squeezing of
Enceladus may
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have transformed it into
a living world,
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but other moons
weren't as lucky.
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They've been torn apart in
vicious fights
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to the death.
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ROWE: There are a huge variety
of moons orbiting Saturn,
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from Titan, a moon larger
than the planet Mercury,
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to objects about the size of
a sports stadium.
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RADEBAUGH: There must be
something dramatic that happened
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to create a system
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that's so complicated
and changing
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before our very eyes.
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ROWE: To understand such
a marked difference in size,
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scientists look for clues in
the moon's orbits around
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Saturn itself.
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Most of the moons of that system
orbit in the same direction.
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That's obviously not
a coincidence.
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That's motion left over
from the formation
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of our solar system.
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ROWE: This suggests the moons
formed around
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the same time as Saturn did.
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4.6 billion years ago,
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the ringless gas giant
grows from gas,
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rock, and ice in
the protoplanetary disk,
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along with a family
of moons.
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This origin story works for
most of Saturn's moons,
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but not for the recently
discovered objects orbiting
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in the opposite direction of
the planet's rotation.
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If there's a moon orbiting in
the other direction,
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it couldn't have formed with
the planet.
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It must have come from
somewhere else.
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ROWE:
Saturn captured these moons.
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But from where?
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WALSH: We think there was a huge
upheaval in the solar system
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over four billion years ago,
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where the giant planets
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went from a close and compact
configuration, started
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having interactions
with each other,
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moved each other around
to end up into the orbits
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that they find today.
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During that process, a lot of
smaller bodies,
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like asteroids
from the distant part
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00:11:53,482 --> 00:11:54,862
of the solar system
got scattered
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every which direction.
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ROWE: During
this ancient upheaval,
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00:12:01,000 --> 00:12:03,517
Saturn grabs some of
the scattered objects.
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00:12:06,413 --> 00:12:09,862
Many bodies now crowd
the region around the planet,
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and that means collisions.
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Some are destructive.
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00:12:19,482 --> 00:12:21,793
Others form new moons.
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00:12:23,172 --> 00:12:24,620
In the cosmic pinball,
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some moons are thrown
out of the system,
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and others,
into Saturn.
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Only one large moon
survives the carnage.
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WALSH: And all of a sudden,
most of the mass
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00:12:37,862 --> 00:12:40,000
of all the satellites is in
that single moon, Titan.
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ROWE: Titan may have formed
from the material in
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00:12:46,275 --> 00:12:50,000
the protoplanetary disk at
the same time as Saturn,
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00:12:50,068 --> 00:12:54,275
but then gorged on the debris
created in the later
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00:12:54,379 --> 00:12:59,379
lunar collisions.
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00:12:59,379 --> 00:13:05,068
It amassed 96 percent of
the material orbiting Saturn
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00:13:05,068 --> 00:13:08,689
and grew so large that it
developed a dense atmosphere.
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00:13:13,000 --> 00:13:15,103
CHRISTIANSEN: When Voyager
photographed Titan,
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00:13:15,172 --> 00:13:17,793
it clearly showed that Titan
had a thick atmosphere,
220
00:13:17,896 --> 00:13:20,275
which was so
incredibly exciting,
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00:13:20,275 --> 00:13:22,172
but it was so dense
and impenetrable,
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00:13:22,172 --> 00:13:24,793
that was all we could see.
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00:13:26,275 --> 00:13:28,413
ROWE:
Two decades after Voyager,
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00:13:28,482 --> 00:13:31,275
the Huygens Probe
launched from Cassini
225
00:13:32,689 --> 00:13:36,689
and plunged through the murky
depths of Titan's atmosphere.
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00:13:42,793 --> 00:13:44,517
DARTNELL:
Our first images of what
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00:13:44,586 --> 00:13:47,000
the Titanic landscape was like
228
00:13:47,103 --> 00:13:52,172
were utterly and truly
mind-blowing.
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00:13:52,172 --> 00:13:53,586
HOWETT:
It showed there were mountains
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00:13:53,586 --> 00:13:54,620
and there was
sort of erosion
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00:13:54,689 --> 00:13:56,586
on those mountains
that looked like liquid
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00:13:56,689 --> 00:13:59,793
had fallen down the mountains
and brought material with it.
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00:14:01,103 --> 00:14:03,172
That liquid must
have come from somewhere.
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00:14:03,275 --> 00:14:05,068
And where else than rain,
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00:14:05,068 --> 00:14:06,275
the weather on Titan?
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00:14:07,931 --> 00:14:10,689
ROWE: We've only found
two places in the solar system
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00:14:10,793 --> 00:14:13,896
with rivers and rain--
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00:14:13,896 --> 00:14:17,758
Earth and Titan.
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00:14:17,758 --> 00:14:20,068
Out of this thick gloom,
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00:14:20,068 --> 00:14:24,206
this is the most similar place
to Earth we've ever seen.
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00:14:24,275 --> 00:14:27,275
ROWE: Similar,
but not identical.
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00:14:29,103 --> 00:14:34,068
That rain filling lakes and
rivers on Titan isn't water.
243
00:14:35,103 --> 00:14:36,482
It's liquid methane.
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00:14:37,896 --> 00:14:41,310
It's like if every oil well,
if every gas station on
245
00:14:41,379 --> 00:14:43,379
Earth started leaking
all over the place,
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00:14:43,482 --> 00:14:46,068
that is what we see on
this world.
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00:14:48,896 --> 00:14:50,758
ROWE: The methane is
a liquid on Titan
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00:14:50,758 --> 00:14:55,413
because the surface temperature
is 290 degrees below zero,
249
00:14:56,689 --> 00:14:59,103
which is a big problem
for life
250
00:14:59,172 --> 00:15:01,103
as we understand it.
251
00:15:02,620 --> 00:15:05,517
We don't know of any organism
that can really survive past
252
00:15:05,586 --> 00:15:08,000
negative 4 degrees Fahrenheit,
and that's just because
253
00:15:08,103 --> 00:15:10,689
cells will tend
to freeze there.
254
00:15:10,758 --> 00:15:12,379
HOWETT:
The cells that we have,
255
00:15:12,482 --> 00:15:15,310
what they're made up from,
these proteins and fatty
256
00:15:15,379 --> 00:15:19,689
material, stop working,
and everything would die.
257
00:15:19,758 --> 00:15:24,379
ROWE: That's what happens to
Earth's water-based cells.
258
00:15:27,068 --> 00:15:32,172
But could methane-based life
survive in extreme cold?
259
00:15:34,896 --> 00:15:38,482
The ALMA telescope spotted
a clue in Titan's nitrogen-
260
00:15:38,586 --> 00:15:41,379
and-methane-rich atmosphere.
261
00:15:41,379 --> 00:15:45,206
With sunlight hitting
the atmosphere of Titan,
262
00:15:45,275 --> 00:15:48,482
things like methane and
nitrogen can get broken apart
263
00:15:48,586 --> 00:15:52,758
and reassembled,
like playing with LEGO blocks,
264
00:15:52,758 --> 00:15:56,000
and then these molecules
recombine to
265
00:15:56,103 --> 00:15:59,000
make new ones,
like vinyl cyanide.
266
00:16:01,068 --> 00:16:03,000
Artist depiction.
267
00:16:03,103 --> 00:16:08,620
ROWE: Used on Earth to make
plastics, vinyl cyanide can
268
00:16:08,689 --> 00:16:11,000
build long chains of molecules,
269
00:16:11,000 --> 00:16:14,586
the type you need to build
cell membranes.
270
00:16:20,620 --> 00:16:23,310
But unlike Earth's
water-based cells,
271
00:16:23,379 --> 00:16:26,206
the extreme cold wouldn't
destroy them.
272
00:16:28,793 --> 00:16:31,000
HOWETT: It could survive
at those low temperatures.
273
00:16:31,000 --> 00:16:35,000
So on Titan, it could be that
this vinyl cyanide is able
274
00:16:35,103 --> 00:16:36,586
to form the membranes
275
00:16:36,586 --> 00:16:38,379
that are required
for cells to develop,
276
00:16:38,379 --> 00:16:41,068
which are required
for life to happen.
277
00:16:44,862 --> 00:16:47,000
ROWE:
And good news--
278
00:16:47,103 --> 00:16:50,068
there's a lot of this stuff
on Titan right now.
279
00:16:52,689 --> 00:16:57,172
There's as much as 10 billion
tons of this vinyl cyanide
280
00:16:57,172 --> 00:16:58,620
in just one of the lakes.
281
00:16:58,689 --> 00:17:00,689
If you want to start
making creatures out of it--
282
00:17:00,793 --> 00:17:02,586
say, I don't know,
a giant squid--
283
00:17:02,689 --> 00:17:04,103
do you like giant squids?
284
00:17:04,172 --> 00:17:07,586
I hope so, because you could
make billions
285
00:17:07,689 --> 00:17:13,103
of giant squids out of
this vinyl cyanide.
286
00:17:13,172 --> 00:17:16,000
ROWE: Saturn's geyser moon, Enceladus,
287
00:17:16,068 --> 00:17:18,517
could have life as we know it.
288
00:17:18,586 --> 00:17:23,586
Titan might have
something truly alien.
289
00:17:23,586 --> 00:17:27,068
It is
an unrelentingly brutal,
290
00:17:27,068 --> 00:17:30,068
cold place
compared to Earth.
291
00:17:30,068 --> 00:17:33,482
But for Titanic life,
it might just be ideal.
292
00:17:35,103 --> 00:17:36,620
COOPER: As we search for life
beyond Earth,
293
00:17:36,689 --> 00:17:40,103
it still comes with a bias of
life as we know it.
294
00:17:40,172 --> 00:17:42,275
And so it's great,
as we continue
295
00:17:42,275 --> 00:17:45,172
to explore and continue to
evolve our definitions,
296
00:17:45,172 --> 00:17:50,103
we can expand our view
of how to search for life.
297
00:17:50,172 --> 00:17:54,275
Maybe the Saturn system
has two living worlds.
298
00:17:56,689 --> 00:18:00,689
ROWE: But for life to thrive
on Titan's surface,
299
00:18:00,793 --> 00:18:04,586
it must survive a storm of
deadly particles
300
00:18:04,689 --> 00:18:06,689
racing out of the Sun
301
00:18:06,793 --> 00:18:08,862
at over a million miles
an hour.
302
00:18:26,275 --> 00:18:29,241
ROWE: The sun provides
light and warmth...
303
00:18:33,034 --> 00:18:37,689
and something else,
something very dangerous--
304
00:18:37,793 --> 00:18:38,793
the solar wind.
305
00:18:42,275 --> 00:18:45,448
These lethal solar particles
can strip away
306
00:18:45,448 --> 00:18:48,655
atmosphere from planets
and moons.
307
00:18:52,000 --> 00:18:54,000
Without an atmosphere,
308
00:18:54,068 --> 00:18:56,448
Earth would be
a barren desert, right?
309
00:18:56,448 --> 00:18:59,068
There wouldn't be any water,
it would just all boil away.
310
00:18:59,137 --> 00:19:01,275
There wouldn't be any life,
311
00:19:02,379 --> 00:19:06,379
ROWE: Luckily, Earth has
a built-in defense system.
312
00:19:07,793 --> 00:19:09,103
SUTTER:
In the center of our Earth,
313
00:19:09,172 --> 00:19:13,551
we have a solid iron core, and
surrounding that is liquid iron
314
00:19:13,551 --> 00:19:17,689
that is constantly moving
and swirling and convecting,
315
00:19:17,793 --> 00:19:19,275
and these complex motions
316
00:19:19,344 --> 00:19:23,275
power up a global-scale
magnetic field
317
00:19:26,965 --> 00:19:28,896
PLAIT: And this acts
like a force field
318
00:19:28,965 --> 00:19:31,482
against the solar wind,
pushes it away,
319
00:19:31,586 --> 00:19:33,344
pushes it around us
so it doesn't hit us.
320
00:19:35,000 --> 00:19:38,103
ROWE: We think
that Saturn's moon, Titan,
321
00:19:38,172 --> 00:19:40,758
has no molten iron core
322
00:19:43,275 --> 00:19:47,482
and therefore no protective
magnetic field.
323
00:19:47,586 --> 00:19:50,172
So it's at the mercy of
the solar wind.
324
00:19:51,379 --> 00:19:53,896
It kind of begs the question,
why does Titan
325
00:19:54,000 --> 00:19:56,482
have such a thick,
dense atmosphere?
326
00:19:56,551 --> 00:20:01,068
ROWE: Titan retaining
an atmosphere without
327
00:20:01,137 --> 00:20:03,965
a protective shield
makes no sense.
328
00:20:06,689 --> 00:20:08,793
SUTTER: Titan doesn't have
a magnetic field,
329
00:20:08,896 --> 00:20:11,241
but Saturn does.
330
00:20:11,241 --> 00:20:14,000
So maybe there's some sort of
interaction between
331
00:20:14,068 --> 00:20:18,689
the atmosphere of Titan and
Saturn's giant magnetic field.
332
00:20:20,448 --> 00:20:23,862
ROWE: The gas giant Saturn
generates a magnetic field
333
00:20:23,862 --> 00:20:26,896
around 600 times larger
than Earth's,
334
00:20:29,344 --> 00:20:33,068
large enough to shield Titan
from the solar wind.
335
00:20:35,379 --> 00:20:38,758
So Titan by itself
is vulnerable.
336
00:20:38,758 --> 00:20:40,586
Saturn is like
the mother ship.
337
00:20:40,689 --> 00:20:43,172
It has this giant
force field
338
00:20:43,275 --> 00:20:44,689
that it can use
to protect Titan.
339
00:20:46,103 --> 00:20:52,000
ROWE: Despite Saturn's embrace,
Titan still loses
340
00:20:52,068 --> 00:20:56,275
some of its atmosphere,
because occasionally,
341
00:20:56,344 --> 00:21:00,896
the moon wanders away from its
protective parent.
342
00:21:00,965 --> 00:21:04,344
Titan orbits inside of
that magnetic field...
343
00:21:04,344 --> 00:21:06,965
mostly, most of the time.
344
00:21:07,000 --> 00:21:08,689
Its orbit isn't
perfectly circular.
345
00:21:08,793 --> 00:21:10,379
It's slightly elliptical.
346
00:21:12,137 --> 00:21:15,344
So as Titan orbits the planet,
for a little bit of time,
347
00:21:15,344 --> 00:21:16,689
about 5 percent of its orbit,
348
00:21:16,758 --> 00:21:19,137
it's actually slightly outside
the magnetic field
349
00:21:19,137 --> 00:21:20,793
before dipping back
in again.
350
00:21:23,344 --> 00:21:24,793
ROWE:
But these short forays into
351
00:21:24,862 --> 00:21:29,379
the firing line don't cause
any lasting damage.
352
00:21:30,655 --> 00:21:33,896
What's really weird is that
there's sort of a residual
353
00:21:33,965 --> 00:21:35,965
magnetic effect on Titan.
354
00:21:36,000 --> 00:21:38,241
When it leaves Saturn's
protective field,
355
00:21:38,241 --> 00:21:40,689
it should just immediately
drop to nothing.
356
00:21:40,758 --> 00:21:43,000
But there still is
this residual field,
357
00:21:43,068 --> 00:21:45,551
protecting it from
the solar wind.
358
00:21:45,551 --> 00:21:48,793
SUTTER: It can maintain the
memory of that magnetic field
359
00:21:48,862 --> 00:21:51,689
and still preserve some
of that protection.
360
00:21:53,000 --> 00:21:55,793
It's almost like Saturn is
trying to teach
361
00:21:55,862 --> 00:21:57,862
Titan how to have
a magnetic field,
362
00:21:57,862 --> 00:21:59,689
and Titan can remember
for a little bit,
363
00:21:59,758 --> 00:22:01,689
but then it needs to come
back home.
364
00:22:03,586 --> 00:22:06,068
ROWE: This magnetic memory
could help
365
00:22:06,137 --> 00:22:09,275
support any life on
Titan's surface,
366
00:22:09,379 --> 00:22:13,379
providing a safe haven that's
protected from the solar wind.
367
00:22:15,965 --> 00:22:17,896
And Cassini spots a way
368
00:22:18,000 --> 00:22:21,068
Saturn's magnetism
might also allow
369
00:22:21,137 --> 00:22:24,344
its moons to develop life.
370
00:22:24,344 --> 00:22:28,482
One of the most amazing
discoveries around Saturn was
371
00:22:28,551 --> 00:22:30,172
that its magnetic field is not
372
00:22:30,275 --> 00:22:32,379
just transporting
charged particles from,
373
00:22:32,448 --> 00:22:36,000
say, the sun, but it's also
transporting material
374
00:22:36,034 --> 00:22:37,482
from one moon to another.
375
00:22:40,896 --> 00:22:43,241
ROWE: Saturn's magnetic field
helps boost
376
00:22:43,241 --> 00:22:45,551
the chance of life on Titan
377
00:22:45,551 --> 00:22:50,551
by stealing material
from its sister moon, Enceladus.
378
00:22:51,896 --> 00:22:54,344
Magnetism is
a strong force, of course,
379
00:22:54,344 --> 00:22:57,241
but to act on a scale
and a range
380
00:22:57,241 --> 00:23:00,068
like this and maybe transport
matter from moon to moon,
381
00:23:00,068 --> 00:23:01,758
that's pretty cool.
382
00:23:03,482 --> 00:23:06,586
ROWE: Saturn's magnetic field
smashes apart
383
00:23:06,655 --> 00:23:11,068
water molecules blasted out
from Enceladus's geysers
384
00:23:11,137 --> 00:23:16,275
and carries the leftover oxygen
to Titan.
385
00:23:16,379 --> 00:23:18,482
SUTTER:
The magnetic field of Saturn
386
00:23:18,551 --> 00:23:21,793
acts like
an inter-lunar highway
387
00:23:21,896 --> 00:23:25,344
in the Saturn system,
transporting oxygen
388
00:23:25,344 --> 00:23:28,172
from Enceladus all the way
to Titan.
389
00:23:28,275 --> 00:23:31,896
ROWE: But there's a problem
when the oxygen tries to
390
00:23:31,965 --> 00:23:36,758
take the Titan exit off of
this inter-lunar highway.
391
00:23:36,758 --> 00:23:39,896
Normally, this oxygen
wouldn't survive
392
00:23:40,000 --> 00:23:41,275
in the atmosphere of Titan.
393
00:23:41,344 --> 00:23:44,172
It would react with the methane
there and create carbon dioxide.
394
00:23:45,655 --> 00:23:47,379
ROWE:
To get to the surface
395
00:23:47,482 --> 00:23:49,862
in one piece,
oxygen hitches
396
00:23:49,862 --> 00:23:53,275
a ride with something
called a fullerene.
397
00:23:58,137 --> 00:23:59,655
Fullerenes are these sort of
398
00:23:59,655 --> 00:24:02,172
soccer ball shaped molecules
that are hollow.
399
00:24:02,275 --> 00:24:04,344
If the oxygen atom
gets in there,
400
00:24:04,344 --> 00:24:07,551
it can be safely transported
through Titan's atmosphere.
401
00:24:09,482 --> 00:24:13,275
ROWE: Once on the surface,
the oxygen could help create
402
00:24:13,379 --> 00:24:15,137
amino acids,
403
00:24:15,137 --> 00:24:18,103
the essential building blocks
of proteins,
404
00:24:18,172 --> 00:24:22,793
another stepping stone for
life to emerge.
405
00:24:26,034 --> 00:24:29,482
Think of all
the complex coincidences
406
00:24:29,551 --> 00:24:31,275
that have to happen
407
00:24:31,344 --> 00:24:34,344
for these chemical reactions
to take place.
408
00:24:34,344 --> 00:24:36,379
If Titan's orbit
was any different,
409
00:24:36,448 --> 00:24:37,793
it simply wouldn't exist.
410
00:24:41,448 --> 00:24:46,068
ROWE: Saturn protects
any potential life on its moons.
411
00:24:47,275 --> 00:24:49,862
And as it turns out,
the moons
412
00:24:49,862 --> 00:24:54,379
return the favor
by helping create
413
00:24:54,448 --> 00:25:00,689
and maintain
Saturn's iconic rings.
414
00:25:16,000 --> 00:25:19,344
ROWE: At 170,000 miles
in diameter,
415
00:25:20,482 --> 00:25:23,034
but only 30 feet thick
in places,
416
00:25:23,103 --> 00:25:27,896
Saturn's beautiful rings have
always stolen the show,
417
00:25:30,793 --> 00:25:34,896
but their origin is still
a mystery.
418
00:25:35,000 --> 00:25:38,586
Saturn has these beautiful
rings that really
419
00:25:38,655 --> 00:25:39,896
define it as a planet,
420
00:25:39,896 --> 00:25:42,000
but its unique in the solar
system in the sense that no
421
00:25:42,068 --> 00:25:45,586
other planet has such
a big ring system.
422
00:25:45,689 --> 00:25:49,586
THALLER: All of the other gas
giants have remnants of a ring,
423
00:25:49,689 --> 00:25:53,482
kind of small, thin, dark rings,
but nothing like Saturn.
424
00:25:53,551 --> 00:25:56,551
So something very different
happened around Saturn.
425
00:25:58,551 --> 00:26:03,137
ROWE: A clue comes from
the rings' composition.
426
00:26:03,137 --> 00:26:06,034
They're around
99 percent water ice,
427
00:26:06,103 --> 00:26:09,000
giving the rings
their sparkling appearance.
428
00:26:10,482 --> 00:26:14,965
This leads astronomers
to a bold theory.
429
00:26:15,000 --> 00:26:18,655
We do not know how Saturn's
icy rings formed.
430
00:26:18,655 --> 00:26:20,275
We're not even sure
how old they are,
431
00:26:20,344 --> 00:26:23,793
but one idea is that
they formed from ice that was
432
00:26:23,896 --> 00:26:26,103
existing previously on a moon.
433
00:26:26,172 --> 00:26:28,965
How amazing is that?
434
00:26:29,000 --> 00:26:34,000
ROWE: Several billion years ago,
Saturn may have been ringless,
435
00:26:35,172 --> 00:26:37,689
with a large, icy moon.
436
00:26:37,793 --> 00:26:41,379
The moon was big enough that
its gravity drew heavier
437
00:26:41,482 --> 00:26:43,275
stuff like rock to its core
438
00:26:43,344 --> 00:26:46,000
and lighter stuff like ice
floated to the top.
439
00:26:46,068 --> 00:26:52,793
ROWE: We think the moon
strayed too close to Saturn.
440
00:26:52,862 --> 00:26:55,896
WALSH: The gravity from Saturn
could tear it apart,
441
00:26:57,758 --> 00:27:00,793
and it could separate the ices
from the rocky parts
442
00:27:00,862 --> 00:27:03,275
and the ices could stay in
orbit and form our rings,
443
00:27:03,344 --> 00:27:06,172
and the rocky parts would get
swallowed up by Saturn.
444
00:27:12,586 --> 00:27:16,172
The death of a large moon
may have built the rings,
445
00:27:20,379 --> 00:27:24,482
but they owe their current
appearance to the moons that
446
00:27:24,551 --> 00:27:26,448
are still alive.
447
00:27:26,448 --> 00:27:29,793
THALLER: When you go back
to Saturn's rings,
448
00:27:29,862 --> 00:27:32,655
time and time again,
they're all slightly different.
449
00:27:32,655 --> 00:27:34,689
They are changing, they are
braiding in and out of
450
00:27:34,758 --> 00:27:37,551
each other-- we had no idea
there would be
451
00:27:37,551 --> 00:27:40,068
so much beauty and so much
mystery in the rings.
452
00:27:42,000 --> 00:27:45,793
ROWE: The behavior of two of
Saturn's moons,
453
00:27:45,862 --> 00:27:48,103
Prometheus and Atlas,
454
00:27:48,172 --> 00:27:50,586
which are embedded in
the rings
455
00:27:50,689 --> 00:27:52,862
is especially surprising.
456
00:27:52,862 --> 00:27:56,103
Some of these smallest moons
457
00:27:56,172 --> 00:27:59,000
are interspersed within
the ring system.
458
00:27:59,068 --> 00:28:03,275
Some of them are doing
something really bizarre.
459
00:28:03,379 --> 00:28:06,793
In some cases, it looks like
the moons were shepherding
460
00:28:06,862 --> 00:28:10,275
the edges of the rings and
keeping them in their place.
461
00:28:11,551 --> 00:28:15,103
ROWE: The moon's gravity
cleans up the rings,
462
00:28:16,379 --> 00:28:19,896
sometimes, sculpting shapes
in their wake.
463
00:28:22,172 --> 00:28:25,068
Saturn's rings aren't static,
and there's some really
464
00:28:25,137 --> 00:28:28,034
fascinating interactions where
moons are clearly pushing on
465
00:28:28,103 --> 00:28:31,000
the rings and causing weird
and cool waves,
466
00:28:31,068 --> 00:28:35,448
making the rings just
that much more beautiful.
467
00:28:35,448 --> 00:28:38,896
HOWETT: The whole dance between
Saturn and its moons,
468
00:28:38,965 --> 00:28:40,689
its rings,
how they all
469
00:28:40,793 --> 00:28:43,448
are interconnected, is just
completely fascinating.
470
00:28:45,586 --> 00:28:47,172
It's a dynamic, amazing,
471
00:28:47,275 --> 00:28:49,758
living, geologically
vibrant place.
472
00:28:53,793 --> 00:28:56,793
ROWE: Saturn's moons may keep
the rings orderly,
473
00:28:58,758 --> 00:29:03,689
but they can't explain
why the rings are so clean,
474
00:29:03,758 --> 00:29:05,172
almost pristine.
475
00:29:07,655 --> 00:29:09,172
PLAIT:
They're too shiny.
476
00:29:09,241 --> 00:29:11,655
If they were billions of
years old,
477
00:29:11,655 --> 00:29:14,034
they should have collected
a lot of dust by now
478
00:29:14,103 --> 00:29:15,275
and be a lot darker.
479
00:29:15,379 --> 00:29:18,275
The fact that they're shiny
kind of implies that
480
00:29:18,344 --> 00:29:22,137
maybe they're a lot younger
than we first thought.
481
00:29:22,137 --> 00:29:25,000
ROWE: Perhaps
the rings we see today
482
00:29:25,034 --> 00:29:27,896
are a more recent upgrade.
483
00:29:29,379 --> 00:29:32,172
The rings might only be
100 million years old,
484
00:29:32,241 --> 00:29:34,344
about the time of
the dinosaurs.
485
00:29:34,344 --> 00:29:37,379
So if the dinosaurs
had invented telescopes,
486
00:29:37,482 --> 00:29:40,379
they could have seen Saturn
without rings.
487
00:29:40,448 --> 00:29:41,655
And it makes you wonder,
is this
488
00:29:41,655 --> 00:29:43,689
the first ring system that
Saturn had?
489
00:29:43,758 --> 00:29:45,482
Or was there another
ring system
490
00:29:45,551 --> 00:29:47,551
that may be slowly
eroded away?
491
00:29:47,551 --> 00:29:50,793
Perhaps a comet or a body came
in too close to Saturn,
492
00:29:50,896 --> 00:29:52,896
and Saturn's gravity
literally tore it apart,
493
00:29:52,965 --> 00:29:54,758
and then we got a brand-new
ring system.
494
00:29:57,068 --> 00:29:59,862
The later dinosaurs could have
watched the rings form,
495
00:30:01,000 --> 00:30:02,793
and then they would have been
wiped out by an asteroid.
496
00:30:04,068 --> 00:30:05,896
Yeah, should have built
better telescopes,
497
00:30:05,965 --> 00:30:08,379
dinosaurs, sucks to be you.
498
00:30:11,068 --> 00:30:14,137
ROWE: We still don't know
why the rings of Saturn
499
00:30:14,137 --> 00:30:15,793
are so clean.
500
00:30:17,482 --> 00:30:19,689
It could be that the rings
really are old, and they have
501
00:30:19,758 --> 00:30:21,034
some sort of cleaning system,
502
00:30:21,103 --> 00:30:22,482
which removes the dust
from them,
503
00:30:22,586 --> 00:30:27,137
making them look young, or they
may actually be young, and this
504
00:30:27,137 --> 00:30:30,379
may be the seventh or eighth
or whatever generation rings.
505
00:30:30,448 --> 00:30:35,482
It is so different than
any other planetary system.
506
00:30:35,551 --> 00:30:37,379
And those mysteries
still exist.
507
00:30:37,482 --> 00:30:41,172
We have some idea
what went on,
508
00:30:41,275 --> 00:30:43,586
but there's a lot that
we don't know about Saturn.
509
00:30:46,379 --> 00:30:49,137
ROWE:
Cassini is changing that.
510
00:30:51,482 --> 00:30:55,482
It's discovered a whole new
moon-making process,
511
00:30:57,689 --> 00:31:00,551
with the rings
taking the lead.
512
00:31:18,275 --> 00:31:21,137
ROWE: Midway through its 13-year
mission to Saturn,
513
00:31:23,482 --> 00:31:26,344
Cassini captures
an intriguing image,
514
00:31:29,000 --> 00:31:31,068
a bright feature
at the edge
515
00:31:31,137 --> 00:31:33,379
of one of Saturn's
outermost rings,
516
00:31:34,379 --> 00:31:36,344
something we'd never
seen before.
517
00:31:38,793 --> 00:31:42,000
I was really excited when
we saw these images of Saturn's
518
00:31:42,034 --> 00:31:44,275
rings, and it looked
like there was a lump,
519
00:31:44,379 --> 00:31:49,000
maybe a moon forming there,
which they nicknamed Peggy.
520
00:31:49,034 --> 00:31:51,034
ROWE:
Named after the mother-in-law
521
00:31:51,103 --> 00:31:53,172
of the scientist
who discovered it,
522
00:31:53,241 --> 00:31:56,586
Peggy was still too small
to be considered
523
00:31:56,655 --> 00:32:02,275
a fully-formed moon,
but nearby orbits
524
00:32:02,379 --> 00:32:06,689
a group of objects that are
just big enough to be moons,
525
00:32:09,482 --> 00:32:11,689
and they are really weird.
526
00:32:13,275 --> 00:32:14,862
These moons are
really unusual.
527
00:32:14,862 --> 00:32:17,862
We don't think of them as like
anything else we've seen.
528
00:32:17,862 --> 00:32:21,551
They're kind of
little fuzzy potatoes or maybe
529
00:32:21,551 --> 00:32:24,689
even like a ravioli is another
one or a croissant.
530
00:32:24,793 --> 00:32:26,017
Why do we always come up
with food?
531
00:32:26,017 --> 00:32:29,344
But at the same time, that's
exactly what they look like.
532
00:32:29,344 --> 00:32:32,758
The most bizarrely-shaped moon
of Saturn is Pan.
533
00:32:32,758 --> 00:32:34,586
It's got these
crisscrossing cracks,
534
00:32:34,655 --> 00:32:37,482
just like bread,
and then around the outside
535
00:32:37,551 --> 00:32:39,689
is a belly band,
it's undulatory.
536
00:32:39,793 --> 00:32:41,344
How would this get there?
537
00:32:44,068 --> 00:32:46,655
ROWE: Cassini
discovered a clue.
538
00:32:49,448 --> 00:32:51,586
Like Saturn's rings,
539
00:32:51,655 --> 00:32:55,482
these moons were made almost
entirely of water ice.
540
00:32:58,551 --> 00:32:59,689
They must have grown from
541
00:32:59,793 --> 00:33:02,965
tiny lumps trapped
within the rings.
542
00:33:04,034 --> 00:33:10,137
PLAIT: They're going to be
extremely fragile,
543
00:33:10,137 --> 00:33:12,793
kind of like a snowflake
orbiting Saturn.
544
00:33:12,862 --> 00:33:15,758
They can start drawing in
material and then can grow.
545
00:33:15,758 --> 00:33:18,275
You can actually imagine
rolling up a snowball
546
00:33:18,379 --> 00:33:21,172
and accumulating more and more
particles on the outside.
547
00:33:21,275 --> 00:33:23,793
And in the same way,
you could accumulate
548
00:33:23,862 --> 00:33:25,241
these clumps
in the rings.
549
00:33:25,241 --> 00:33:27,241
And if they're near
the edge of the rings,
550
00:33:27,241 --> 00:33:31,965
perhaps they actually break free
and go out to form tiny moons.
551
00:33:34,586 --> 00:33:38,034
ROWE: The size of
these space snowballs,
552
00:33:38,103 --> 00:33:41,241
tens of miles across or less,
553
00:33:41,241 --> 00:33:43,793
helps explain
their unusual shapes.
554
00:33:47,172 --> 00:33:50,896
The size of the moon actually
affects its shape in that once
555
00:33:51,000 --> 00:33:52,482
you get below a certain
size threshold,
556
00:33:52,551 --> 00:33:54,275
you cannot be round anymore.
557
00:33:54,344 --> 00:33:56,172
That's because the strength of
the rock or the ice
558
00:33:56,275 --> 00:33:59,000
in this case is too great
to be overcome by gravity,
559
00:33:59,068 --> 00:34:02,103
and so the kind of oblong
shapes can be maintained.
560
00:34:04,586 --> 00:34:06,655
ROWE:
Add in a few collisions,
561
00:34:06,655 --> 00:34:10,793
and you get Saturn's ravioli-
and croissant-shaped moons.
562
00:34:13,655 --> 00:34:16,034
It's a bizarre process but
leads to a beautiful form.
563
00:34:16,103 --> 00:34:20,137
We know the moons affect
the rings, but it looks
564
00:34:20,137 --> 00:34:22,793
like in this case, the rings
affect the moons, too.
565
00:34:22,896 --> 00:34:24,896
They're connected
in both directions.
566
00:34:30,758 --> 00:34:33,793
ROWE: The rings form
a moon factory,
567
00:34:37,793 --> 00:34:41,862
capable of building countless
generations of new worlds.
568
00:34:43,793 --> 00:34:47,344
This is a dance of physics.
569
00:34:49,379 --> 00:34:52,758
PLAIT: If moonlets can form
by these icy ring particles,
570
00:34:52,758 --> 00:34:55,103
they'll grow, and then
their natural gravitational
571
00:34:55,172 --> 00:34:57,689
interaction with the rings will
make them move out.
572
00:34:57,758 --> 00:34:59,275
They keep growing
as they move out.
573
00:34:59,344 --> 00:35:01,862
But then another moon forms
where the first one was.
574
00:35:01,862 --> 00:35:04,793
So you keep getting these
growing moons, right,
575
00:35:04,896 --> 00:35:07,172
and this process repeats
like on a conveyor belt.
576
00:35:07,241 --> 00:35:09,793
And what you wind up with is
bigger moons orbiting
577
00:35:09,896 --> 00:35:12,068
farther out from Saturn
and smaller ones
578
00:35:12,137 --> 00:35:13,379
orbiting closer in.
579
00:35:16,241 --> 00:35:19,896
ROWE: But Saturn's conveyor belt
will eventually break down.
580
00:35:24,551 --> 00:35:26,000
When ultraviolet light from
581
00:35:26,034 --> 00:35:30,344
the sun interacts with
ring particles,
582
00:35:30,344 --> 00:35:34,586
it throws their steady orbit
around Saturn out of whack.
583
00:35:36,793 --> 00:35:39,896
The sun energizes the rings,
and it gives them a charge.
584
00:35:40,000 --> 00:35:41,482
This charge means
they can get picked
585
00:35:41,586 --> 00:35:43,689
up by the magnetic field
of Saturn.
586
00:35:43,793 --> 00:35:46,275
So these little tiny charged
particles then are lifted
587
00:35:46,344 --> 00:35:47,655
out of the rings,
588
00:35:47,655 --> 00:35:49,793
follow along
the magnetic field lines,
589
00:35:49,862 --> 00:35:51,896
rain down into
Saturn's atmosphere.
590
00:35:54,551 --> 00:35:59,275
ROWE: The charged particles
are tiny ice crystals.
591
00:35:59,344 --> 00:36:02,000
They rain down onto Saturn,
592
00:36:04,655 --> 00:36:07,896
enough to fill
an Olympic-sized swimming pool
593
00:36:07,965 --> 00:36:09,000
every second.
594
00:36:12,862 --> 00:36:15,586
In less than
100 million years,
595
00:36:15,655 --> 00:36:19,689
Saturn's rings
will be gone.
596
00:36:19,758 --> 00:36:25,000
There will be no material
to build new moons.
597
00:36:25,068 --> 00:36:28,862
Saturn's moons and rings,
598
00:36:28,862 --> 00:36:31,068
they almost make me feel
bittersweet, because they
599
00:36:31,137 --> 00:36:34,034
show you the beauty of
what physics can create,
600
00:36:34,103 --> 00:36:36,103
But also the fleeting-ness.
601
00:36:36,172 --> 00:36:39,000
They'll be gone soon,
and that makes me sad.
602
00:36:42,000 --> 00:36:44,000
ROWE:
The closer we look,
603
00:36:44,034 --> 00:36:46,896
the more intriguing
the Saturn system becomes.
604
00:36:53,275 --> 00:36:55,482
And now, scientists
605
00:36:55,551 --> 00:36:57,586
have an audacious
new plan
606
00:37:00,965 --> 00:37:05,000
to fly a drone on one of
Saturn's moons.
607
00:37:18,655 --> 00:37:21,758
Saturn is one of
the most dynamic places
608
00:37:21,758 --> 00:37:24,413
in the solar system.
609
00:37:25,551 --> 00:37:27,379
We want to go back there,
610
00:37:27,448 --> 00:37:30,344
to explore its moons up close
611
00:37:30,413 --> 00:37:33,620
and hunt directly
for Life 2.0.
612
00:37:36,137 --> 00:37:38,413
For so long, we've been
emphasizing that to have
613
00:37:38,482 --> 00:37:39,724
a habitable planet,
614
00:37:39,724 --> 00:37:41,793
you have to be warm, you have
to be close to your star.
615
00:37:43,034 --> 00:37:45,275
In fact, the most likely
chance we have to find
616
00:37:45,344 --> 00:37:48,793
life maybe way in the outer
solar system in Saturn's moons.
617
00:37:49,793 --> 00:37:52,482
But we won't know for sure
until we send
618
00:37:52,551 --> 00:37:54,862
another mission there,
specifically to look for life.
619
00:37:56,689 --> 00:37:58,517
ROWE:
The Huygens Probe gave us
620
00:37:58,586 --> 00:38:01,206
a tantalizing glimpse of
Titan's surface,
621
00:38:05,172 --> 00:38:08,241
but it wasn't equipped
to search for life.
622
00:38:10,068 --> 00:38:14,517
Now, scientists are
developing Dragonfly,
623
00:38:14,586 --> 00:38:19,206
a space helicopter that can
search for life.
624
00:38:21,275 --> 00:38:23,413
Dragonfly is
an amazing mission.
625
00:38:23,482 --> 00:38:25,586
We're sending this to Titan
to better
626
00:38:25,655 --> 00:38:28,379
understand how life might
arise in a very different
627
00:38:28,448 --> 00:38:29,413
context than Earth.
628
00:38:31,965 --> 00:38:33,896
One thing we know
absolutely for certain
629
00:38:33,965 --> 00:38:37,586
is that Titan has interesting,
complex chemistry.
630
00:38:37,655 --> 00:38:38,896
The question now is,
631
00:38:38,965 --> 00:38:42,172
does that chemistry actually
turn into biology?
632
00:38:45,793 --> 00:38:49,551
The million-dollar question,
is this a living world?
633
00:38:56,517 --> 00:38:59,862
ROWE:
April 2021.
634
00:39:02,172 --> 00:39:05,655
We test the concept
of a space helicopter.
635
00:39:10,275 --> 00:39:13,172
Ingenuity making
the first remote flight on
636
00:39:13,241 --> 00:39:17,517
another world launches into
the thin Martian atmosphere.
637
00:39:19,482 --> 00:39:21,586
Mars is a really difficult
place to fly,
638
00:39:21,655 --> 00:39:25,482
because the atmosphere is 100
times thinner than Earth's.
639
00:39:25,551 --> 00:39:27,793
And remember, it's
the atmosphere that provides
640
00:39:27,896 --> 00:39:31,000
the support and the lift
for a helicopter to fly.
641
00:39:31,034 --> 00:39:32,448
So in order
for Ingenuity to fly,
642
00:39:32,517 --> 00:39:34,689
it had to spin
very fast in order
643
00:39:34,793 --> 00:39:36,172
to even get itself
off the ground.
644
00:39:40,862 --> 00:39:43,896
ROWE: Fortunately, Titan's
thick atmosphere
645
00:39:43,965 --> 00:39:46,379
is much more
helicopter friendly.
646
00:39:48,862 --> 00:39:51,689
The contrast between Ingenuity
and the Dragonfly mission
647
00:39:51,793 --> 00:39:52,689
is really funny,
648
00:39:52,689 --> 00:39:55,620
because Mars has almost
no atmosphere,
649
00:39:55,689 --> 00:39:58,103
less than 1 percent the
atmospheric pressure of Earth.
650
00:39:58,172 --> 00:40:01,344
On Titan,
you have exactly the opposite.
651
00:40:01,413 --> 00:40:03,448
The air pressure near
the surface of Titan can be
652
00:40:03,517 --> 00:40:06,034
four times as much as
the air pressure on Earth.
653
00:40:06,103 --> 00:40:08,793
So for a helicopter
or something like a drone,
654
00:40:08,896 --> 00:40:10,051
something like
an octocopter,
655
00:40:10,051 --> 00:40:13,275
the lower the gravity is
and the denser the atmosphere,
656
00:40:13,344 --> 00:40:14,551
the better you can fly.
657
00:40:15,413 --> 00:40:18,344
LANZA: So Titan just begs to be
explored, because you get
658
00:40:18,413 --> 00:40:20,310
a lot of lift, and you can
actually carry heavy
659
00:40:20,379 --> 00:40:21,344
instruments with you.
660
00:40:22,689 --> 00:40:25,275
It allows you to fly
through the atmosphere,
661
00:40:25,344 --> 00:40:28,551
collect samples, and determine
what the prebiotic chemistry
662
00:40:28,620 --> 00:40:29,724
is on that moon.
663
00:40:31,689 --> 00:40:34,241
If ever there was a world
built for flying drones,
664
00:40:34,310 --> 00:40:36,310
it's Titan.
665
00:40:36,379 --> 00:40:40,241
ROWE: Dragonfly is scheduled
to launch in 2027,
666
00:40:43,172 --> 00:40:46,000
arriving at Titan
around seven years later,
667
00:40:46,034 --> 00:40:50,275
completing the journey of moon
discovery that began
668
00:40:50,344 --> 00:40:52,758
with Voyager
and Cassini.
669
00:40:55,241 --> 00:40:56,965
DURDA:
We completely transformed
670
00:40:57,000 --> 00:41:00,344
our picture of the Saturn
system, the rings and the moons.
671
00:41:00,413 --> 00:41:02,034
It's a far more complex
672
00:41:02,103 --> 00:41:04,344
environment than
we ever dreamed possible.
673
00:41:04,413 --> 00:41:05,896
The moons have come
alive, right?
674
00:41:06,000 --> 00:41:09,068
They're not boring, dead
ice balls, and it just
675
00:41:09,137 --> 00:41:11,379
begs generation after generation
of spacecraft follow up.
676
00:41:14,517 --> 00:41:15,965
ROWE: We're only
just beginning to
677
00:41:16,000 --> 00:41:18,896
unravel the secrets of
Saturn's moons.
678
00:41:21,275 --> 00:41:25,586
And with more than 80 to
explore, the Saturn system is
679
00:41:25,655 --> 00:41:28,206
a gift that'll keep on giving.
680
00:41:31,103 --> 00:41:33,793
Saturn was the very first
thing I ever
681
00:41:33,862 --> 00:41:35,758
saw through a telescope
when I was a kid.
682
00:41:35,758 --> 00:41:39,689
And here I am-- clearly,
I was inspired by Saturn,
683
00:41:39,758 --> 00:41:41,620
by its beauty.
684
00:41:41,689 --> 00:41:43,965
THALLER: Saturn has always been
my favorite planet.
685
00:41:44,000 --> 00:41:45,275
Everything you want
686
00:41:45,344 --> 00:41:48,137
is there-- violence,
colliding moons,
687
00:41:48,206 --> 00:41:51,689
how new rings form, new moons
form over time.
688
00:41:53,068 --> 00:41:54,758
PLAIT:
And there might be life there.
689
00:41:54,758 --> 00:41:58,172
There might be life in
more than one place there.
690
00:41:58,241 --> 00:42:02,172
One destination, one planetary
zip code, gives you all of that.
691
00:42:02,241 --> 00:42:03,689
I say go back to Saturn.
55493
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