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[distant explosions]

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00:00:06,310 --> 00:00:09,660
TYSON: We are a long way
from home, and from our time.

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00:00:10,140 --> 00:00:13,190
This was our Milky Way
when the galaxy was young

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00:00:13,361 --> 00:00:15,451
and more fertile
than it is today.

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00:00:15,624 --> 00:00:19,284
Back then,
she birthed 30 times as many
stars as she does now...

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00:00:19,889 --> 00:00:23,109
a firestorm of star creation.

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It's a summer night,
11 billion years ago.

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We're on the
planet of another star,

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00:00:28,985 --> 00:00:31,805
one with an ideal view of
the Milky Way galaxy's

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00:00:31,988 --> 00:00:34,118
chaotic stellar nursery.

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Our own star was a child
of the galaxy's later years,

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00:00:40,518 --> 00:00:43,218
and that may be one
of the reasons we exist.

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After the short-lived,
more massive stars died out,

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there was time...

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00:00:48,700 --> 00:00:52,270
another five billion years,
for those dead stars to bequeath

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00:00:52,443 --> 00:00:54,973
their heavier elements to us.

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00:00:55,142 --> 00:00:58,192
These elements enriched
and nurtured the formation

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of the planets and
moons of our solar system.

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00:01:01,713 --> 00:01:06,373
And we ourselves are
made of that star stuff.

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Those blazing pink clouds of
hydrogen gas are the swaddling

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of countless new-born stars.

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See those
bright blue splashes?

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They're clusters of
slightly older sibling stars.

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Gravity's embrace will
transform this amorphous

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collection of gas
and dust into the galaxy
we call home today.

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[explosion]

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Our sun is born.

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The star endows her
surrounding worlds

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with precious minerals,
diamonds and green olivine...

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00:02:01,643 --> 00:02:03,823
a mineral that will play
a major role in our story.

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The stars make planets,
moons and comets.

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There's Jupiter, the firstborn
world of our solar system.

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00:02:22,098 --> 00:02:25,318
These future planets
and moons are awash
with organic molecules...

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00:02:26,363 --> 00:02:29,373
the chemical
building blocks of life.

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This is their inheritance
from the deaths of other stars.

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Does the cosmos give
rise to life as naturally

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as it makes
stars and worlds?

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This is our voyage to
the heart of that mystery.

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[theme music plays].

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00:03:18,850 --> 00:03:24,940
♪ ♪

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♪ ♪

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TYSON: Long, long ago,
when our world was young,

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there was a city at
the bottom of the sea
that covered the Earth.

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It took tens of thousands
of years to build this city,

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but there was no life
on this world back then.

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So who built these
submarine skyscrapers?

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00:04:42,151 --> 00:04:43,941
Nature did.

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She made them with carbon
dioxide and the same minerals

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00:04:46,982 --> 00:04:49,852
she uses to make
seashells and pearls...

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00:04:50,420 --> 00:04:52,250
calcium carbonate.

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But these soaring towers
were nothing compared to what

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happened beneath them.

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We'll need to get
1,000 times smaller to see it.

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Doesn't look
like much, does it?

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But just wait.

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Our restless
Mother Earth cracked open,

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and cold sea water poured
down into her hot rocky mantle,

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getting richer in
organic molecules and minerals,

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including a green
jewel called olivine.

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This mix of water and
minerals got so hot that it

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shot out of
her with great force.

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The mixture became trapped
in the pores of the carbonate

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rocks that would
later become her towers.

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These pores were incubators,
safe places where the organic

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molecules could
become more concentrated.

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This is how we think that the
rocks built life's first home.

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It was the beginning,
at least in our little

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part of the cosmos,
of an enduring collaboration

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between the minerals of earth,

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the rocks and life.

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See those snaky cracks?

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That's how this
process got its name.

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Serpentinization.

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It's the evidence for
the conversion of water and

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carbon dioxide into
hydrogen and methane...

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the organic molecules that
fueled this earthshaking event.

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Those scientists who
search for life on other worlds,

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they used to say,
"follow the water,"

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because water is the most
basic requirement for life.

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Now, they also say,
"follow the rocks,"

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because serpentinization
is so closely associated with

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the processes that
make life possible.

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To witness the main event,
we have to get even smaller.

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At this scale,
these caves look vast,

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but they're actually
the tiny pores in
the mortar of the towers.

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These jewels are the
organic molecules which are,

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like everything, including
you and me, made of atoms.

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In order to turn these
inanimate jewels into jewelry,

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the stuff of life,
it takes energy.

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We think it happened in a
treasure cave like this one.

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The energy came from the
reaction between the alkaline

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water trapped
within the towers

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and the acidic
water of the ocean.

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That ancient treasure
chest filled with rings and

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bracelets and necklaces,

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longer and more
complex molecules,

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until the greatest
treasure of all...

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Life.

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We think it was that
chemical reaction that provided

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the energy that
powered the first cell.

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That was the spark
that electrified the
building blocks of life

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into something alive.

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Over time,
the towers decayed,

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making it possible for
the fledgling life within them

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to escape and evolve.

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♪ ♪

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What you've just seen is
the most plausible scientific

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creation myth we have
today for the origin of life.

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This hypothesis
required the reunification

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of four long
separated scientific fields:

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biology, chemistry,
physics and geology.

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We think life first
took hold in the rocks.

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And from day one,
life was an escape artist,

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always wanting to break free,
to conquer new worlds.

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Even the great big
ocean couldn't contain it.

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If that's the true story
of how life got started,

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it was long ago,
back before the sky was blue,

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before the moon spun away
from us to where it is today.

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Back when the planet
was an ocean world,

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with waters
bloodred with iron.

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Life would remake the
world, the sea and the sky.

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But life doesn't always
act in its own best interest.

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There came a
day of reckoning,

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when life nearly
destroyed itself.

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TYSON: The Cosmic Calendar
is a way for us to wrap our

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heads around the
vastness of time.

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To grasp the
history of the cosmos,

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00:10:08,999 --> 00:10:11,919
from the birth of our
universe to this very moment,

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we've compressed all of it
into a single calendar year.

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On this scale,
every month represents
about a billion years.

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Every day represents
nearly 40 million years.

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That first day of the cosmic
year began with the Big Bang,

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almost 14 billion years ago.

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Nothing really happened
in our neck of the universe

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until about three
billion years later...

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00:10:44,687 --> 00:10:47,857
March 15 of the cosmic year,

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when our Milky Way
galaxy began to form.

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Six billion years after that,
our star, the Sun, was born.

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It was August 31st
on the Cosmic Calendar.

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Jupiter and the other planets,
including our own,

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would soon follow.

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This was our planet nearly
four billion years ago...

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September 21st on
the Cosmic Calendar,

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when we believe life began.

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The atmosphere was
a hydrocarbon smog.

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No oxygen to breathe
and no one to breathe it.

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We've only recently begun
to appreciate how powerfully

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life has shaped the planet.

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When we think about the
ways life has changed Earth,

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the first things that come
to mind are the green expanses

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of forests, and
the sprawling cities.

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But life began transforming
the planet long before there

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were any such things.

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A billion years after
that tiny glimmer at
the bottom of the sea,

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life had become a
global phenomenon thanks to

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a champion that to this
day has never been vanquished.

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I give you the cyanobacteria.

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In business for
2.7 billion years,

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cyanobacteria can
make a living anywhere.

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Fresh water, salt water,
hot springs, salt mines...

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makes no difference,
it's all home to them.

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Over the next 400 million
years, the cyanobacteria...

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taking in carbon dioxide
and giving back oxygen,

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turned the sky blue.

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But the cyanobacteria
didn't just change the sky,

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they reached into
the very rocks themselves

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and changed them, too.

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Oxygen rusted the iron,

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working its magic
on the minerals.

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Of the 5,000 kinds
of minerals on Earth,

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3,500 of them
arose as a result of
the oxygen made by life.

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But here comes
that day of reckoning.

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Cyanobacteria were
the dominant life-form
on this planet,

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wreaking havoc
wherever they went,

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changing the landscape,
the water and the skies.

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This was 2.3
billion years ago,

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or late October on
the Cosmic Calendar.

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But the cyanobacteria shared
the planet with other beings:

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The anaerobes, life-forms
that had come of age before

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cyanobacteria had begun to
pollute the Earth with oxygen.

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For the anaerobes,
oxygen was poison,

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but the cyanobacteria
wouldn't stop loading up

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00:14:28,041 --> 00:14:30,741
the atmosphere
with the stuff.

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00:14:31,000 --> 00:14:33,130
For the anaerobes,
and nearly all of the other

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00:14:33,307 --> 00:14:37,217
life on Earth, it
was an oxygen apocalypse.

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00:14:37,528 --> 00:14:40,008
The lone survivors among
the anaerobes were those

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00:14:40,183 --> 00:14:42,583
who sought refuge
at the bottom of the sea,

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00:14:42,751 --> 00:14:45,621
deep in the sediment
where the oxygen
could not reach them.

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00:14:52,108 --> 00:14:57,288
The cyanobacteria acted
like oxygen-pumping machines.

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They continued in overdrive,
and 400 million years later,

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they brought about
an even more radical
change to the planet.

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00:15:05,643 --> 00:15:09,043
Remember those serpentinized
rocks at the bottom of the sea

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00:15:09,212 --> 00:15:11,782
that were cranking out
hydrogen and methane?

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00:15:12,389 --> 00:15:14,779
Methane is a
powerful greenhouse gas,

195
00:15:14,957 --> 00:15:18,267
and back then it was the main
thing keeping the planet warm.

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00:15:19,396 --> 00:15:23,526
But once again,
the oxygen produced
by life shook things up.

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00:15:23,879 --> 00:15:27,269
It gobbled up the methane,
producing carbon dioxide,

198
00:15:27,448 --> 00:15:29,708
a much less
potent greenhouse gas...

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00:15:29,885 --> 00:15:32,185
meaning it was not as
efficient at trapping heat

200
00:15:32,366 --> 00:15:34,536
in Earth's atmosphere.

201
00:15:34,716 --> 00:15:37,756
Earth's temperature
began to plunge.

202
00:15:44,073 --> 00:15:48,953
Life, the escape artist,
busted out of the icy death grip

203
00:15:49,122 --> 00:15:51,302
that entombed the planet.

204
00:15:51,472 --> 00:15:54,562
The corpses of dead bacteria
left behind a planetwide

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00:15:54,736 --> 00:15:57,296
reservoir of carbon dioxide.

206
00:15:58,131 --> 00:16:02,051
Volcanoes pumped
the carbon dioxide in huge
quantities into the atmosphere,

207
00:16:03,397 --> 00:16:06,307
warming the planet
and melting the ice.

208
00:16:06,487 --> 00:16:08,267
Over the next billion years,

209
00:16:08,445 --> 00:16:11,265
life and the rocks
continued their elaborate dance,

210
00:16:11,448 --> 00:16:14,538
taking the planet
through freezes and thaws.

211
00:16:14,712 --> 00:16:18,982
Then, 540 million years ago,
something wondrous happened.

212
00:16:22,546 --> 00:16:26,376
Life, which had been all
about microbes and simple

213
00:16:26,550 --> 00:16:30,600
multicellular creatures,
suddenly took off in what's

214
00:16:30,772 --> 00:16:32,902
called the Cambrian Explosion.

215
00:16:34,210 --> 00:16:37,610
Life grew legs,
eyes, gills, teeth,

216
00:16:39,128 --> 00:16:43,178
and rapidly began
to evolve the forms of
its stunning diversity.

217
00:16:44,655 --> 00:16:47,915
We don't yet know what it was
that allowed life to diversify

218
00:16:48,094 --> 00:16:51,274
so dramatically, but we
have some plausible theories.

219
00:16:52,576 --> 00:16:54,356
It could have been all
those calcium minerals in

220
00:16:54,535 --> 00:16:56,925
the seawater that
came from the volcanoes.

221
00:16:57,103 --> 00:16:59,713
Life had grown a
backbone and put on a shell.

222
00:17:00,802 --> 00:17:03,462
It had found a way to
collaborate with the rocks

223
00:17:03,631 --> 00:17:05,721
to make its own armor.

224
00:17:05,894 --> 00:17:10,034
Now life could grow
larger and venture forth
into new territories.

225
00:17:12,640 --> 00:17:15,210
Or maybe it was the
protection afforded by the

226
00:17:15,382 --> 00:17:18,252
canopy built by
the cyanobacteria.

227
00:17:19,125 --> 00:17:22,255
The oxygenation
of the atmosphere
created the ozone layer.

228
00:17:23,999 --> 00:17:27,129
This made it possible
for life to break out of the

229
00:17:27,307 --> 00:17:30,917
safety of the oceans
and inhabit the land without

230
00:17:31,093 --> 00:17:34,843
being assaulted by the
sun's deadly ultraviolet rays.

231
00:17:36,185 --> 00:17:40,615
For billions of years,
all life could do was ooze.

232
00:17:41,495 --> 00:17:46,935
Now, life began to
swim, run, jump and fly.

233
00:17:48,850 --> 00:17:52,720
Life, the escape artist,
had gotten so good at wriggling

234
00:17:52,897 --> 00:17:57,157
out of every confine, no
prison on Earth could hold it.

235
00:17:58,860 --> 00:18:00,600
And there will come a day,

236
00:18:00,775 --> 00:18:03,905
when life would
even escape from Earth.

237
00:18:05,519 --> 00:18:08,569
Life will not be contained.

238
00:18:15,529 --> 00:18:21,189
♪ ♪

239
00:18:26,801 --> 00:18:29,461
Retracing life's odyssey
back to the very beginning

240
00:18:29,630 --> 00:18:31,550
required a new
kind of science,

241
00:18:32,285 --> 00:18:34,635
one that
reunited the disciplines.

242
00:18:34,809 --> 00:18:37,249
The man who founded this
new approach also happened

243
00:18:37,420 --> 00:18:39,900
to be an escape
artist himself.

244
00:18:40,075 --> 00:18:42,685
He fled history's
most implacable killers,

245
00:18:42,860 --> 00:18:46,520
right here in this forest,
jesting at his tormentors

246
00:18:46,690 --> 00:18:50,130
every step of the way.

247
00:18:57,527 --> 00:18:59,087
TYSON: Remember this place?

248
00:18:59,268 --> 00:19:01,268
It's London's
Royal Institution,

249
00:19:01,444 --> 00:19:03,844
where Michael Faraday
spent his life.

250
00:19:04,273 --> 00:19:07,363
Back in his time, in the
first half of the 19th century,

251
00:19:08,103 --> 00:19:10,803
the intimate relationship
between life and the rocks

252
00:19:10,975 --> 00:19:13,325
had yet to be discovered.

253
00:19:14,544 --> 00:19:17,374
Before science could
tackle the origin of life,

254
00:19:17,547 --> 00:19:19,027
it had to change.

255
00:19:19,201 --> 00:19:21,641
This development was
foretold by a scientist

256
00:19:21,812 --> 00:19:25,772
whose gifts to the world,
were decidedly mixed.

257
00:19:26,817 --> 00:19:30,557
Christian Friedrich Schonbein
was a German-Swiss chemist who

258
00:19:30,734 --> 00:19:34,434
was conducting an experiment
on using electricity to reduce

259
00:19:34,608 --> 00:19:36,828
water into its two
chemical constituents,

260
00:19:37,611 --> 00:19:40,401
oxygen and hydrogen.

261
00:19:40,701 --> 00:19:42,961
Schonbein thought he
smelled something familiar,

262
00:19:43,138 --> 00:19:45,658
something like the
air after a thunderstorm.

263
00:19:46,489 --> 00:19:49,139
Schonbein had
discovered ozone.

264
00:19:49,710 --> 00:19:51,970
Remember, that's the layer
in the atmosphere that made

265
00:19:52,147 --> 00:19:55,147
it possible for our distant
ancestors to leave the water

266
00:19:55,324 --> 00:19:57,764
for the land, and it
still protects us from

267
00:19:57,935 --> 00:20:00,235
ultraviolet rays to this day.

268
00:20:01,939 --> 00:20:04,459
Schonbein loved to experiment.

269
00:20:04,638 --> 00:20:07,338
So much so that his wife
famously exacted a promise

270
00:20:07,510 --> 00:20:10,910
from him not to use their
kitchen as his laboratory.

271
00:20:29,706 --> 00:20:33,876
♪ ♪

272
00:20:34,711 --> 00:20:36,371
SCHONBEIN: Oh.

273
00:20:37,236 --> 00:20:40,366
TYSON: Schonbein had
just invented a new weapon
of mass destruction.

274
00:20:48,290 --> 00:20:51,120
A chemical explosive
more powerful than gunpowder.

275
00:20:52,381 --> 00:20:55,821
Upon further refinement,
gun cotton would industrialize

276
00:20:55,993 --> 00:20:58,953
warfare on a horrendous scale.

277
00:21:00,389 --> 00:21:03,219
But it was also Schonbein
who had a prophetic vision of

278
00:21:03,392 --> 00:21:05,312
a new field of science.

279
00:21:05,481 --> 00:21:07,441
He wrote in 1838:

280
00:21:07,614 --> 00:21:10,014
"Before the mystery of
the genesis of our planets

281
00:21:10,181 --> 00:21:12,451
and their inorganic
matter can be revealed,

282
00:21:13,010 --> 00:21:16,750
a comparative science of
geochemistry must be launched."

283
00:21:18,407 --> 00:21:20,537
50 years later,
the man who would realize

284
00:21:20,714 --> 00:21:23,154
Schonbein's dream was born.

285
00:21:24,108 --> 00:21:26,498
He was another German-Swiss.

286
00:21:26,676 --> 00:21:29,416
Victor Goldschmidt
was so brilliant,

287
00:21:29,592 --> 00:21:32,902
he was offered a position
here at the University of Oslo

288
00:21:33,074 --> 00:21:36,304
without ever taking a
test or earning a degree.

289
00:21:36,860 --> 00:21:40,340
That was in 1909,
when he was only 21.

290
00:21:41,082 --> 00:21:45,002
Three years later,
he was awarded Norway's
greatest scientific prize.

291
00:21:48,611 --> 00:21:52,661
Victor Goldschmidt saw
the Earth as a single system.

292
00:21:52,833 --> 00:21:55,313
He knew that in order
to get the whole picture,

293
00:21:55,488 --> 00:21:59,098
you couldn't
just know physics,
chemistry, or geology...

294
00:21:59,405 --> 00:22:01,795
you had to know them all.

295
00:22:02,625 --> 00:22:05,405
This was in the early days of
the study of the basic elements.

296
00:22:06,716 --> 00:22:09,416
Goldschmidt applied this new
knowledge to create his own

297
00:22:09,589 --> 00:22:11,369
version of the periodic table,

298
00:22:12,069 --> 00:22:14,509
one that is
still in use today.

299
00:22:14,942 --> 00:22:17,292
It illuminated how crystals
and complex minerals could

300
00:22:17,466 --> 00:22:19,896
be formed from
more basic elements.

301
00:22:20,077 --> 00:22:22,427
Goldschmidt was
discovering how matter evolves

302
00:22:22,602 --> 00:22:26,822
into mountains and
cliffs and canyons.

303
00:22:31,219 --> 00:22:34,439
In 1928, he made a
fateful decision to accept

304
00:22:34,614 --> 00:22:36,664
an appointment at
the University of Gottingen,

305
00:22:36,833 --> 00:22:40,583
in Germany,
where an institute had
been built just for him.

306
00:22:40,924 --> 00:22:44,894
His colleagues
thought these were
his happiest years, until...

307
00:22:45,059 --> 00:22:47,799
[hammering]

308
00:22:50,717 --> 00:22:53,367
1933,

309
00:22:56,244 --> 00:22:58,734
when Adolf Hitler came to power.

310
00:22:59,378 --> 00:23:02,248
Goldschmidt was Jewish,
but not observant.

311
00:23:02,424 --> 00:23:04,734
Hitler changed
all that for him.

312
00:23:04,905 --> 00:23:07,425
He now began to publicly
identify himself with the

313
00:23:07,603 --> 00:23:09,523
local Jewish community.

314
00:23:09,692 --> 00:23:12,522
Hitler made it compulsory
for everyone to list any

315
00:23:12,695 --> 00:23:16,085
Jewish forbearers going
back several generations.

316
00:23:16,612 --> 00:23:19,222
There were those who tried
to conceal a grandfather who

317
00:23:19,398 --> 00:23:21,748
might land them in
a concentration camp.

318
00:23:21,922 --> 00:23:24,752
But Goldschmidt proudly
declared on his forms that all

319
00:23:24,925 --> 00:23:27,315
of his ancestors were Jewish.

320
00:23:27,493 --> 00:23:30,843
Hitler and Hermann Goring,
founder of the Gestapo,

321
00:23:31,018 --> 00:23:32,848
were not amused.

322
00:23:36,763 --> 00:23:38,553
GOLDSCHMIDT: Hmm?

323
00:23:38,721 --> 00:23:40,461
TYSON: They personally sent a
letter to Goldschmidt telling

324
00:23:40,636 --> 00:23:42,726
him he was summarily dismissed
from his university position.

325
00:23:48,688 --> 00:23:51,518
He fled to Norway with
only the clothes on his back.

326
00:23:58,393 --> 00:24:01,143
Goldschmidt concentrated
his research on olivine,

327
00:24:01,570 --> 00:24:03,530
that green jewel
of a mineral left over from

328
00:24:03,703 --> 00:24:05,883
the formation
of the solar system.

329
00:24:06,445 --> 00:24:08,835
He was fascinated by
its power to withstand even

330
00:24:09,012 --> 00:24:11,582
the highest temperatures.

331
00:24:12,102 --> 00:24:14,712
He was the first to speculate
that olivine may have played

332
00:24:14,888 --> 00:24:18,278
a role in setting the
stage for the origin of life.

333
00:24:18,848 --> 00:24:21,108
At the same time, he
wondered about the presence

334
00:24:21,285 --> 00:24:23,635
of olivine
throughout the cosmos.

335
00:24:24,550 --> 00:24:27,990
This was the beginning of
a field called cosmochemistry.

336
00:24:29,772 --> 00:24:33,252
In 1940, when the
Germans invaded Norway,

337
00:24:33,428 --> 00:24:37,038
Goldschmidt took to carrying
a cyanide capsule in his pocket

338
00:24:37,214 --> 00:24:39,224
so that he could kill
himself instantly if the

339
00:24:39,390 --> 00:24:41,830
Gestapo came for him.

340
00:24:42,132 --> 00:24:44,832
When a fellow scientist
asked if he could get one, too,

341
00:24:45,005 --> 00:24:46,915
Goldschmidt answered:

342
00:24:47,094 --> 00:24:50,404
"This poison is for
chemistry professors only.

343
00:24:50,576 --> 00:24:54,186
You, as a physicist,
will have to use a rope."

344
00:25:00,063 --> 00:25:01,413
[knock]

345
00:25:01,587 --> 00:25:02,847
NAZI: Herr Goldschmidt.

346
00:25:03,023 --> 00:25:04,423
TYSON: But when
the Germans arrived,

347
00:25:04,590 --> 00:25:06,770
Goldschmidt kept the
cyanide in his pocket.

348
00:25:08,115 --> 00:25:09,245
NAZI: Goldschmidt.

349
00:25:09,420 --> 00:25:11,900
[speaking in German].

350
00:25:14,425 --> 00:25:16,905
TYSON: He was sent to the
Berg concentration camp before

351
00:25:17,080 --> 00:25:19,610
they were ready to
deport him to Auschwitz,

352
00:25:20,127 --> 00:25:23,827
a place he told
friends that "had not
been highly recommended."

353
00:25:30,311 --> 00:25:32,141
Goldschmidt was too
important a scientist

354
00:25:32,313 --> 00:25:35,013
for the Nazis to exterminate.

355
00:25:35,185 --> 00:25:37,835
He was given the chance of
survival if he would put

356
00:25:38,014 --> 00:25:40,284
his science in the
service of the Reich.

357
00:25:41,409 --> 00:25:44,849
But Goldschmidt dared
to toy with his captors.

358
00:25:45,195 --> 00:25:48,895
He would lead the Germans on
a scientific wild goose chase.

359
00:25:49,069 --> 00:25:52,419
He sent them searching
for nonexistent minerals

360
00:25:52,594 --> 00:25:54,994
and deceived them into
believing these were resources

361
00:25:55,510 --> 00:25:58,170
that would be
critical to the war effort.

362
00:25:58,905 --> 00:26:01,945
His ruse could have been
discovered at any moment,

363
00:26:02,125 --> 00:26:04,075
and that would have meant
certain death in the most

364
00:26:04,258 --> 00:26:06,778
fiendish way possible.

365
00:26:08,131 --> 00:26:11,481
By the end of 1942,
the Norwegian Resistance knew

366
00:26:11,657 --> 00:26:14,047
that Goldschmidt was
in the gravest danger.

367
00:26:14,877 --> 00:26:17,657
They arranged for
him to escape across
the Swedish frontier.

368
00:26:26,628 --> 00:26:29,278
Goldschmidt spent the
rest of the war in Sweden,

369
00:26:29,457 --> 00:26:33,417
and then England, contributing
his knowledge to the Allies.

370
00:26:33,766 --> 00:26:35,326
Always in frail health,

371
00:26:35,506 --> 00:26:38,546
he never recovered from
the hardships of the war.

372
00:26:38,727 --> 00:26:42,947
Victor Goldschmidt
died a year and
a half after it was over.

373
00:26:43,427 --> 00:26:45,817
But during that period,
he wrote a research paper on

374
00:26:45,995 --> 00:26:48,735
the complex organic
molecules that he thought might

375
00:26:48,911 --> 00:26:51,571
have led to the
origin of life on Earth.

376
00:26:51,740 --> 00:26:54,400
And the ideas in that
paper remain central in our

377
00:26:54,569 --> 00:26:57,619
effort to understand
how life came to be.

378
00:27:02,577 --> 00:27:06,757
Goldschmidt never knew that
the generations of geochemists

379
00:27:06,929 --> 00:27:10,629
who came after him would
consider him their founder.

380
00:27:12,761 --> 00:27:16,111
Among his last
wishes was a simple request.

381
00:27:17,070 --> 00:27:19,120
He wanted to be cremated and

382
00:27:19,289 --> 00:27:22,509
to have his ashes
encased in an urn...

383
00:27:23,032 --> 00:27:26,782
made of the thing he believed
to be the stuff of life,

384
00:27:27,863 --> 00:27:30,913
his beloved olivine.

385
00:27:31,867 --> 00:27:34,697
The universe makes galaxies.

386
00:27:34,870 --> 00:27:37,480
Galaxies make stars.

387
00:27:37,656 --> 00:27:40,876
Stars make worlds.

388
00:27:41,311 --> 00:27:45,101
Are there other
Lost Cities of Life
in the cosmos?

389
00:27:45,751 --> 00:27:47,801
Come with me.

390
00:27:55,325 --> 00:27:58,415
TYSON: There are dues to be
paid for cosmic citizenship.

391
00:27:58,807 --> 00:28:01,377
As a spacefaring species,
you have to worry about

392
00:28:01,549 --> 00:28:04,769
contaminating the worlds you
visit and about bringing

393
00:28:04,944 --> 00:28:08,774
back alien stowaways
that might pose a danger
to your home world.

394
00:28:09,992 --> 00:28:13,602
There are protocols
for planetary protection.

395
00:28:14,040 --> 00:28:17,870
NASA designates
five categories
of worlds in the cosmos.

396
00:28:19,436 --> 00:28:22,656
Earth's moon, for instance,
is a Category-1 world...

397
00:28:23,571 --> 00:28:27,181
a place so lifeless,
we pose no threat to it,

398
00:28:27,357 --> 00:28:30,837
and it poses no threat to us.

399
00:28:31,535 --> 00:28:36,105
The riskiest mission of all is a
Restricted Category-5 world,

400
00:28:36,279 --> 00:28:38,929
like this one, Mars.

401
00:28:39,326 --> 00:28:41,546
The conditions
for indigenous life...

402
00:28:41,720 --> 00:28:45,380
in the past,
or even now, hidden in
some subsurface recess,

403
00:28:46,159 --> 00:28:48,249
are not beyond possible.

404
00:28:48,422 --> 00:28:50,512
We have to be very careful,

405
00:28:50,685 --> 00:28:54,645
for our own sake and
for the life that could
conceivably be there.

406
00:28:55,864 --> 00:28:59,134
The Restricted Cat-5
designation is a recognition

407
00:28:59,302 --> 00:29:01,392
of life's genius for escape.

408
00:29:01,565 --> 00:29:04,695
It applies to sample return
missions from those worlds

409
00:29:04,873 --> 00:29:07,403
where life may
have gotten started...

410
00:29:07,876 --> 00:29:11,836
those worlds that may have,
or once may have had,

411
00:29:12,011 --> 00:29:15,621
Lost Cities of Life lying
at the bottom of their seas.

412
00:29:16,537 --> 00:29:19,757
But in a sense, our
robot emissaries themselves...

413
00:29:19,932 --> 00:29:22,022
our landers,
rovers and orbiters,

414
00:29:22,195 --> 00:29:25,365
are a manifestation of
life's relentless imperative

415
00:29:25,546 --> 00:29:29,376
to seek out and
take new territory, and
this means that some of

416
00:29:29,550 --> 00:29:33,250
our emissaries have
to be destroyed as soon
as their missions are over.

417
00:29:34,947 --> 00:29:37,337
Like, poor Juno.

418
00:29:37,863 --> 00:29:40,083
After a multiyear
reconnaissance of Jupiter,

419
00:29:40,256 --> 00:29:43,036
NASA is sending
her to her death.

420
00:29:43,346 --> 00:29:45,386
Not because they were
worried about Jupiter.

421
00:29:45,566 --> 00:29:48,216
There's hardly any chance
that one of our spacecraft

422
00:29:48,395 --> 00:29:51,915
could compromise future
investigations of
the giant gas planet.

423
00:29:52,703 --> 00:29:55,923
Any rogue microbe would
catch a downdraft and sink where

424
00:29:56,098 --> 00:29:58,928
it would be broiled
by the scathing temperatures.

425
00:29:59,362 --> 00:30:02,502
That's why Jupiter's
only a Category-2 world.

426
00:30:02,670 --> 00:30:05,980
But one of Jupiter's moons
is a Restricted Cat-5,

427
00:30:06,543 --> 00:30:09,163
and NASA can't take
the chance that Juno might

428
00:30:09,329 --> 00:30:11,509
inadvertently crash into it.

429
00:30:12,767 --> 00:30:16,207
Europa is another one of only
three Restricted Cat-5 worlds

430
00:30:16,379 --> 00:30:19,029
in the solar system,
and one of Jupiter's 80

431
00:30:19,208 --> 00:30:21,908
and still counting, moons.

432
00:30:33,919 --> 00:30:36,789
Michael Faraday discovered
Earth's magnetic field,

433
00:30:36,965 --> 00:30:39,095
and there's one
around Jupiter, too.

434
00:30:39,272 --> 00:30:41,452
We can see it if we switch
from looking at Jupiter in

435
00:30:41,622 --> 00:30:44,362
visible light to looking
at it in radio waves.

436
00:30:46,279 --> 00:30:51,019
Jupiter's magnetic
field is much stronger
and 18,000 times bigger.

437
00:30:51,632 --> 00:30:55,112
It's a gigantic trap
for charged particles
that are the solar wind.

438
00:30:55,766 --> 00:30:58,546
That's one of the things
that lights up the aurora,

439
00:30:58,726 --> 00:31:01,206
the northern and southern
Lights on Jupiter,

440
00:31:01,468 --> 00:31:04,428
and it does the
same thing on Earth.

441
00:31:09,215 --> 00:31:11,825
Imagine what it's like for
little Europa and her sister

442
00:31:12,000 --> 00:31:15,440
moons to live so close
to the king of the Planets.

443
00:31:16,178 --> 00:31:19,048
Massive Jupiter holds Europa
to him in a gravitational

444
00:31:19,225 --> 00:31:22,745
embrace so powerful
that in four billion years,

445
00:31:22,924 --> 00:31:26,154
she has never been able to
turn her face away from his.

446
00:31:27,929 --> 00:31:30,849
Jupiter's hold on her
is so fierce that it
tears her skin apart.

447
00:31:32,455 --> 00:31:34,885
See those broad scars?

448
00:31:35,067 --> 00:31:36,757
Watch them closely and listen.

449
00:31:36,982 --> 00:31:39,592
[colliding rocks]

450
00:31:40,463 --> 00:31:44,473
That's the sound of a world
being gravitationally tormented.

451
00:31:44,641 --> 00:31:48,521
It's called tidal flexing,
and it's not just Jupiter,

452
00:31:49,298 --> 00:31:52,038
her sister moons
pull on her, too.

453
00:31:52,649 --> 00:31:55,999
We are half a billion
miles from the sun's warmth,

454
00:31:56,175 --> 00:31:58,865
five times farther
away than Earth is,

455
00:31:59,047 --> 00:32:02,397
but this tidal flexing
keeps Europa toasty inside.

456
00:32:04,009 --> 00:32:06,659
Beneath her chaotic surface,
there's an ocean ten times

457
00:32:06,837 --> 00:32:10,147
deeper than the
deepest seas on Earth.

458
00:32:25,334 --> 00:32:28,514
♪ ♪

459
00:32:28,685 --> 00:32:33,125
We're on our way to
another Restricted Cat-5 world.

460
00:32:33,299 --> 00:32:34,599
No, not Saturn.

461
00:32:34,778 --> 00:32:37,088
Saturn's another Cat-2.

462
00:32:38,391 --> 00:32:42,221
Any life passing
through those cloud belts
wouldn't have a chance.

463
00:32:42,743 --> 00:32:45,053
They're made
mostly of ammonia.

464
00:32:45,224 --> 00:32:47,754
Below them are
bands of water vapor.

465
00:32:47,922 --> 00:32:52,582
In one of our future
voyages, we'll go there
at a terrible cost.

466
00:32:54,537 --> 00:32:56,057
It's not Titan, either.

467
00:32:56,235 --> 00:32:58,715
Titan's another
Category-2 world.

468
00:32:58,889 --> 00:33:01,499
Just as with Saturn, the
possibility of us interfering

469
00:33:01,675 --> 00:33:05,235
with the life that
might be there is too remote.

470
00:33:05,548 --> 00:33:07,508
Of course, there's always
the chance that Titan life

471
00:33:07,681 --> 00:33:10,341
is stranger than
our ability to imagine.

472
00:33:10,510 --> 00:33:12,900
Even if that's the case,
there is little likelihood

473
00:33:13,078 --> 00:33:15,948
that any form of
Earth life could harm it.

474
00:33:19,606 --> 00:33:23,826
There she is, our
Restricted Cat-5 world.

475
00:33:34,751 --> 00:33:37,971
TYSON: There's a
world in our solar system
that may harbor life.

476
00:33:39,887 --> 00:33:42,717
You're looking at two of
the first people ever to see it.

477
00:33:43,760 --> 00:33:46,420
William Herschel saw
farther into the deep waters

478
00:33:46,589 --> 00:33:48,979
of the cosmic ocean
than anyone before him.

479
00:33:50,115 --> 00:33:53,065
His son, John,
would also become
a distinguished astronomer.

480
00:33:54,293 --> 00:33:58,253
But tonight is back
when John was a child
in the summer of 1802.

481
00:33:59,689 --> 00:34:02,609
That's when we first met
them on an earlier voyage.

482
00:34:03,780 --> 00:34:05,870
WILLIAM: John, I want
to show you something.

483
00:34:06,609 --> 00:34:08,739
Come with me.

484
00:34:13,616 --> 00:34:16,316
TYSON: This was then the
largest telescope on Earth

485
00:34:16,489 --> 00:34:18,319
and would be for 50 years.

486
00:34:22,190 --> 00:34:25,110
CAROLINE: Well,
what have we here? Hmm?

487
00:34:25,280 --> 00:34:28,330
Isn't it awfully late
for a little boy to be up?

488
00:34:28,892 --> 00:34:31,852
JOHN: Father has promised
to show me something,
Aunt Caroline.

489
00:34:32,026 --> 00:34:34,116
TYSON: William's sister,
Caroline Herschel,

490
00:34:34,289 --> 00:34:37,509
was a world-renowned
astronomer in her own right.

491
00:34:37,684 --> 00:34:40,994
She was the first woman
anywhere on Earth to be paid

492
00:34:41,166 --> 00:34:43,336
for being a scientist.

493
00:34:45,387 --> 00:34:47,477
She was just four-foot-three.

494
00:34:47,650 --> 00:34:49,170
When Caroline
was ten years old,

495
00:34:49,348 --> 00:34:51,348
she was stricken with typhus.

496
00:34:51,524 --> 00:34:54,834
She lost part of
the vision in her left
eye and stopped growing.

497
00:34:55,180 --> 00:34:59,270
And yet, she
defied the limitations
of her time to a point.

498
00:35:01,838 --> 00:35:03,798
Caroline had just
published her work in the

499
00:35:03,971 --> 00:35:06,971
"Catalogue of Nebulae
and Clusters of Stars,"

500
00:35:07,409 --> 00:35:10,199
but it was under her
brother William's name.

501
00:35:10,978 --> 00:35:14,018
It was 1802, after all.

502
00:35:14,416 --> 00:35:16,896
Her nephew, John, would
grow up to build on her

503
00:35:17,071 --> 00:35:20,121
work and create the
"New General Catalogue."

504
00:35:21,336 --> 00:35:26,646
Many astronomical bodies
are still designated
by their NGC number today.

505
00:35:31,041 --> 00:35:35,441
WILLIAM: A few more degrees
east and a degree north.

506
00:35:35,872 --> 00:35:37,182
ASSISTANT: Yes, sir.

507
00:35:42,401 --> 00:35:48,451
WILLIAM: Stop, stop!
There she is.

508
00:35:49,799 --> 00:35:52,669
JOHN: Father! I've
never seen that before.

509
00:35:53,238 --> 00:35:54,938
Is it a new star?

510
00:35:55,109 --> 00:35:58,939
WILLIAM: No, son,
it's a new moon.

511
00:35:59,200 --> 00:36:01,290
I call it Saturn Two.

512
00:36:01,463 --> 00:36:05,253
JOHN: Oh, but Father,
we must think of a
better name than that.

513
00:36:06,076 --> 00:36:08,636
WILLIAM: That's
your job, my boy.

514
00:36:08,818 --> 00:36:11,558
TYSON: And John would do
exactly as his father asked.

515
00:36:11,734 --> 00:36:15,264
He named the moon Enceladus,
after the Giant in Greek

516
00:36:15,434 --> 00:36:18,444
mythology who was the son
of the Earth and the Sky.

517
00:36:19,786 --> 00:36:22,786
Enceladus fought the goddess
Athena in an epic struggle

518
00:36:22,963 --> 00:36:24,793
for control of the universe.

519
00:36:34,453 --> 00:36:36,723
You don't have to be an
astrobiologist to know at

520
00:36:36,890 --> 00:36:39,890
first glance that life
is everywhere on Earth.

521
00:36:41,590 --> 00:36:45,550
It's changed virtually
every square inch of the place.

522
00:36:45,899 --> 00:36:48,159
From an alien point of view,
Earth would certainly have a

523
00:36:48,336 --> 00:36:51,336
Restricted Cat-5 status.

524
00:36:52,688 --> 00:36:55,818
But Enceladus keeps its
secrets hidden deep inside.

525
00:37:10,315 --> 00:37:15,015
♪ ♪

526
00:37:22,109 --> 00:37:25,499
Those geysers of ice and
water vapor are shooting out

527
00:37:25,678 --> 00:37:28,898
of Enceladus
at 800 miles per hour.

528
00:37:29,508 --> 00:37:32,948
They're this moon's
contribution to the outermost
so-called "E" ring of Saturn.

529
00:37:34,991 --> 00:37:36,301
But there's a
lot more in them...

530
00:37:36,471 --> 00:37:39,081
nitrogen, ammonia, methane.

531
00:37:40,562 --> 00:37:43,262
And where there's methane,
there may be olivine.

532
00:37:44,392 --> 00:37:48,312
Enceladus has been at this
for at least 100 million years.

533
00:37:48,875 --> 00:37:52,265
It could keep cranking
out water for another
nine billion years.

534
00:37:54,881 --> 00:37:56,881
Where's all that
water coming from?

535
00:38:16,032 --> 00:38:19,692
The blue snowflakes plummet at
more than 1,000 miles per hour.

536
00:38:20,646 --> 00:38:24,166
We've come here to the
southern hemisphere because

537
00:38:24,345 --> 00:38:26,475
that's where the
ice crust is thinnest.

538
00:38:26,782 --> 00:38:29,832
It's only a
couple of miles thick.

539
00:38:32,092 --> 00:38:34,492
That's why it's the best
possible place to gain access

540
00:38:34,660 --> 00:38:37,100
to the underground ocean.

541
00:38:42,450 --> 00:38:44,580
Okay, now's the
time for a warning:

542
00:38:44,757 --> 00:38:47,847
What you see here is
entirely based on evidence.

543
00:38:48,021 --> 00:38:50,201
That global ocean,
the crazy curtain of geysers,

544
00:38:51,633 --> 00:38:53,113
that weird snow
at the surface...

545
00:38:54,027 --> 00:38:55,417
it's all real.

546
00:38:55,594 --> 00:38:57,514
We have multiple
observations from the Cassini

547
00:38:57,683 --> 00:39:00,953
mission telling us that this
is what awaits us on Enceladus.

548
00:39:03,602 --> 00:39:07,212
But we're about to enter the
realm of informed speculation.

549
00:39:07,954 --> 00:39:11,174
This is what the leading space
scientists think we might find

550
00:39:11,349 --> 00:39:15,569
when we send a spacecraft
to dive straight into
the heart of Enceladus.

551
00:39:17,355 --> 00:39:20,045
[geyser erupting]

552
00:39:33,458 --> 00:39:36,198
When water up here is
exposed to the vacuum of space,

553
00:39:37,113 --> 00:39:40,203
it turns to snow.

554
00:39:49,648 --> 00:39:52,608
And that scum
is the stuff of life...

555
00:39:52,781 --> 00:39:55,131
organic molecules.

556
00:39:55,305 --> 00:39:58,955
It makes you wonder what could
be waiting for us down below.

557
00:40:00,006 --> 00:40:01,696
And that's a
long way from here,

558
00:40:01,877 --> 00:40:04,487
because we're in an ocean
that's about ten times deeper

559
00:40:04,663 --> 00:40:07,103
than the oceans of Earth.

560
00:40:10,146 --> 00:40:12,536
Very promising.

561
00:40:12,714 --> 00:40:16,374
That's carbon and hydrogen,
and the pH of the water is

562
00:40:16,544 --> 00:40:18,464
just like the
early ocean on Earth.

563
00:40:37,173 --> 00:40:43,573
♪ ♪

564
00:41:01,633 --> 00:41:04,373
♪ ♪

565
00:41:04,549 --> 00:41:07,379
Why would this City of Life
be larger than the one at the

566
00:41:07,552 --> 00:41:09,552
bottom of the ocean on Earth?

567
00:41:13,427 --> 00:41:15,727
Maybe it's because the
gravity on Enceladus is so

568
00:41:15,908 --> 00:41:18,128
much weaker than
it is on Earth.

569
00:41:18,737 --> 00:41:22,127
With less gravity,
the towers are lighter,

570
00:41:22,305 --> 00:41:24,475
and they can grow taller.

571
00:41:27,528 --> 00:41:29,268
The currents are strong,

572
00:41:29,443 --> 00:41:31,713
and they may have
toppled some of the towers.

573
00:41:44,371 --> 00:41:47,031
Victor Goldschmidt's olivine.

574
00:41:47,853 --> 00:41:51,383
The rocks have
made a place for life.

575
00:41:53,423 --> 00:41:56,563
But has life had
enough time to take hold?

576
00:41:57,819 --> 00:42:02,219
All I know is,
never underestimate
the escape artist.

577
00:42:22,670 --> 00:42:25,330
You know, it's a
funny thing about us.

578
00:42:25,499 --> 00:42:27,629
We think we're the story.

579
00:42:27,806 --> 00:42:30,936
We're the end all
and be all of the cosmos.

580
00:42:31,418 --> 00:42:34,938
And yet, for all we know,
we're just the by-product of

581
00:42:35,117 --> 00:42:37,507
geochemical forces...

582
00:42:37,685 --> 00:42:41,555
ones that are unfolding
throughout the universe.

583
00:42:50,829 --> 00:42:56,009
Galaxies make stars,
stars make worlds,

584
00:43:00,882 --> 00:43:05,192
and for all we know,
planets and moons make life.

585
00:43:08,498 --> 00:43:11,498
Does that make
life less wondrous?

586
00:43:12,241 --> 00:43:14,201
Or more?

587
00:43:15,070 --> 00:43:16,640
Captioned by
Cotter Captioning Services.