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00:00:05,367 --> 00:00:08,734
TYSON: We are a long way
from home, and from our time.

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00:00:09,200 --> 00:00:12,333
This was our Milky Way
when the galaxy was young

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00:00:12,467 --> 00:00:14,934
and more fertile
than it is today.

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00:00:15,066 --> 00:00:18,767
Back then,
she birthed 30 times as many
stars as she does now...

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00:00:19,367 --> 00:00:22,567
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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one with an ideal view of
the Milky Way galaxy's

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00:00:31,467 --> 00:00:33,633
chaotic stellar nursery.

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

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00:00:39,967 --> 00:00:42,700
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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00:00:47,600 --> 00:00:51,867
another five billion years,
for those dead stars to bequeath

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their heavier elements to us.

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These elements enriched
and nurtured the formation

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of the planets and
moons of our solar system.

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00:01:01,233 --> 00:01:05,867
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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00:02:01,133 --> 00:02:03,367
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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These future planets
and moons are awash
with organic molecules...

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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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♪ ♪

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♪ ♪

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00:04:08,533 --> 00:04:11,600
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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Nature did.

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She made them with carbon
dioxide and the same minerals

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she uses to make
seashells and pearls...

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00:04:49,934 --> 00:04:51,834
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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00:06:47,700 --> 00:06:50,734
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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00:07:44,166 --> 00:07:46,000
bracelets and necklaces,

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longer and more
complex molecules,

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00:07:48,100 --> 00:07:51,133
until the greatest
treasure of all...

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00:07:51,633 --> 00:07:53,500
Life.

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00:07:53,967 --> 00:07:55,934
We think it was that
chemical reaction that provided

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00:07:56,066 --> 00:07:58,900
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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00:08:48,667 --> 00:08:51,367
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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00:09:07,233 --> 00:09:11,000
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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00:09:13,934 --> 00:09:16,934
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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00:09:24,867 --> 00:09:27,967
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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00:10:04,467 --> 00:10:06,367
heads around the
vastness of time.

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To grasp the
history of the cosmos,

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00:10:08,500 --> 00:10:11,433
from the birth of our
universe to this very moment,

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00:10:12,166 --> 00:10:14,967
we've compressed all of it
into a single calendar year.

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00:10:15,734 --> 00:10:19,500
On this scale,
every month represents
about a billion years.

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00:10:20,266 --> 00:10:24,100
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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00:10:40,967 --> 00:10:44,100
until about three
billion years later...

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00:10:44,233 --> 00:10:47,300
March 15 of the cosmic year,

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00:10:47,633 --> 00:10:51,667
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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00:12:35,900 --> 00:12:38,667
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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00:13:10,900 --> 00:13:13,400
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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00:13:21,266 --> 00:13:26,233
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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00:14:09,433 --> 00:14:13,233
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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00:14:27,600 --> 00:14:30,233
the atmosphere
with the stuff.

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00:14:30,567 --> 00:14:32,700
For the anaerobes,
and nearly all of the other

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00:14:32,834 --> 00:14:36,700
life on Earth, it
was an oxygen apocalypse.

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00:14:37,033 --> 00:14:39,600
The lone survivors among
the anaerobes were those

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00:14:39,734 --> 00:14:42,100
who sought refuge
at the bottom of the sea,

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00:14:42,233 --> 00:14:45,166
deep in the sediment
where the oxygen
could not reach them.

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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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00:15:05,166 --> 00:15:08,667
Remember those serpentinized
rocks at the bottom of the sea

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00:15:08,800 --> 00:15:11,333
that were cranking out
hydrogen and methane?

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00:15:11,967 --> 00:15:14,367
Methane is a
powerful greenhouse gas,

194
00:15:14,500 --> 00:15:17,867
and back then it was the main
thing keeping the planet warm.

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00:15:18,934 --> 00:15:23,066
But once again,
the oxygen produced
by life shook things up.

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00:15:23,433 --> 00:15:26,867
It gobbled up the methane,
producing carbon dioxide,

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00:15:27,000 --> 00:15:29,300
a much less
potent greenhouse gas...

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00:15:29,433 --> 00:15:31,800
meaning it was not as
efficient at trapping heat

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00:15:31,934 --> 00:15:34,133
in Earth's atmosphere.

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00:15:34,266 --> 00:15:37,300
Earth's temperature
began to plunge.

201
00:15:43,633 --> 00:15:48,533
Life, the escape artist,
busted out of the icy death grip

202
00:15:48,667 --> 00:15:50,834
that entombed the planet.

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00:15:50,967 --> 00:15:54,233
The corpses of dead bacteria
left behind a planetwide

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00:15:54,367 --> 00:15:56,834
reservoir of carbon dioxide.

205
00:15:57,700 --> 00:16:01,667
Volcanoes pumped
the carbon dioxide in huge
quantities into the atmosphere,

206
00:16:03,000 --> 00:16:05,934
warming the planet
and melting the ice.

207
00:16:06,066 --> 00:16:07,900
Over the next billion years,

208
00:16:08,033 --> 00:16:10,867
life and the rocks
continued their elaborate dance,

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00:16:11,000 --> 00:16:14,166
taking the planet
through freezes and thaws.

210
00:16:14,300 --> 00:16:18,533
Then, 540 million years ago,
something wondrous happened.

211
00:16:22,066 --> 00:16:25,934
Life, which had been all
about microbes and simple

212
00:16:26,066 --> 00:16:30,200
multicellular creatures,
suddenly took off in what's

213
00:16:30,333 --> 00:16:32,467
called the Cambrian Explosion.

214
00:16:33,734 --> 00:16:37,133
Life grew legs,
eyes, gills, teeth,

215
00:16:38,633 --> 00:16:42,767
and rapidly began
to evolve the forms of
its stunning diversity.

216
00:16:44,166 --> 00:16:47,500
We don't yet know what it was
that allowed life to diversify

217
00:16:47,633 --> 00:16:50,800
so dramatically, but we
have some plausible theories.

218
00:16:52,133 --> 00:16:54,000
It could have been all
those calcium minerals in

219
00:16:54,133 --> 00:16:56,567
the seawater that
came from the volcanoes.

220
00:16:56,700 --> 00:16:59,333
Life had grown a
backbone and put on a shell.

221
00:17:00,433 --> 00:17:03,100
It had found a way to
collaborate with the rocks

222
00:17:03,233 --> 00:17:05,200
to make its own armor.

223
00:17:05,333 --> 00:17:09,600
Now life could grow
larger and venture forth
into new territories.

224
00:17:12,166 --> 00:17:14,800
Or maybe it was the
protection afforded by the

225
00:17:14,934 --> 00:17:17,834
canopy built by
the cyanobacteria.

226
00:17:18,700 --> 00:17:21,867
The oxygenation
of the atmosphere
created the ozone layer.

227
00:17:23,567 --> 00:17:26,734
This made it possible
for life to break out of the

228
00:17:26,867 --> 00:17:30,500
safety of the oceans
and inhabit the land without

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00:17:30,633 --> 00:17:34,433
being assaulted by the
sun's deadly ultraviolet rays.

230
00:17:35,767 --> 00:17:40,166
For billions of years,
all life could do was ooze.

231
00:17:41,033 --> 00:17:46,500
Now, life began to
swim, run, jump and fly.

232
00:17:48,400 --> 00:17:52,367
Life, the escape artist,
had gotten so good at wriggling

233
00:17:52,500 --> 00:17:56,800
out of every confine, no
prison on Earth could hold it.

234
00:17:58,467 --> 00:18:00,233
And there will come a day,

235
00:18:00,367 --> 00:18:03,500
when life would
even escape from Earth.

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00:18:05,166 --> 00:18:08,166
Life will not be contained.

237
00:18:15,166 --> 00:18:20,800
♪ ♪

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00:18:26,367 --> 00:18:29,066
Retracing life's odyssey
back to the very beginning

239
00:18:29,200 --> 00:18:31,100
required a new
kind of science,

240
00:18:31,834 --> 00:18:34,200
one that
reunited the disciplines.

241
00:18:34,333 --> 00:18:36,867
The man who founded this
new approach also happened

242
00:18:37,000 --> 00:18:39,500
to be an escape
artist himself.

243
00:18:39,633 --> 00:18:42,266
He fled history's
most implacable killers,

244
00:18:42,400 --> 00:18:46,133
right here in this forest,
jesting at his tormentors

245
00:18:46,266 --> 00:18:49,700
every step of the way.

246
00:18:57,266 --> 00:18:58,834
TYSON: Remember this place?

247
00:18:58,967 --> 00:19:01,000
It's London's
Royal Institution,

248
00:19:01,133 --> 00:19:03,500
where Michael Faraday
spent his life.

249
00:19:04,000 --> 00:19:07,100
Back in his time, in the
first half of the 19th century,

250
00:19:07,800 --> 00:19:10,533
the intimate relationship
between life and the rocks

251
00:19:10,667 --> 00:19:13,000
had yet to be discovered.

252
00:19:14,200 --> 00:19:17,133
Before science could
tackle the origin of life,

253
00:19:17,266 --> 00:19:18,734
it had to change.

254
00:19:18,867 --> 00:19:21,333
This development was
foretold by a scientist

255
00:19:21,467 --> 00:19:25,433
whose gifts to the world,
were decidedly mixed.

256
00:19:26,467 --> 00:19:30,233
Christian Friedrich Schönbein
was a German-Swiss chemist who

257
00:19:30,367 --> 00:19:34,133
was conducting an experiment
on using electricity to reduce

258
00:19:34,266 --> 00:19:36,500
water into its two
chemical constituents,

259
00:19:37,300 --> 00:19:40,000
oxygen and hydrogen.

260
00:19:40,333 --> 00:19:42,667
Schönbein thought he
smelled something familiar,

261
00:19:42,800 --> 00:19:45,333
something like the
air after a thunderstorm.

262
00:19:46,166 --> 00:19:48,767
Schönbein had
discovered ozone.

263
00:19:49,333 --> 00:19:51,667
Remember, that's the layer
in the atmosphere that made

264
00:19:51,800 --> 00:19:54,834
it possible for our distant
ancestors to leave the water

265
00:19:54,967 --> 00:19:57,467
for the land, and it
still protects us from

266
00:19:57,600 --> 00:19:59,934
ultraviolet rays to this day.

267
00:20:01,600 --> 00:20:04,133
Schönbein loved to experiment.

268
00:20:04,266 --> 00:20:07,000
So much so that his wife
famously exacted a promise

269
00:20:07,133 --> 00:20:10,567
from him not to use their
kitchen as his laboratory.

270
00:20:29,333 --> 00:20:33,500
♪ ♪

271
00:20:34,333 --> 00:20:35,934
SCHÖNBEIN: Oh.

272
00:20:36,800 --> 00:20:40,000
TYSON: Schönbein had
just invented a new weapon
of mass destruction.

273
00:20:47,867 --> 00:20:50,767
A chemical explosive
more powerful than gunpowder.

274
00:20:52,066 --> 00:20:55,533
Upon further refinement,
gun cotton would industrialize

275
00:20:55,667 --> 00:20:58,600
warfare on a horrendous scale.

276
00:21:00,066 --> 00:21:02,934
But it was also Schönbein
who had a prophetic vision of

277
00:21:03,066 --> 00:21:05,000
a new field of science.

278
00:21:05,133 --> 00:21:07,100
He wrote in 1838:

279
00:21:07,233 --> 00:21:09,667
"Before the mystery of
the genesis of our planets

280
00:21:09,800 --> 00:21:12,033
and their inorganic
matter can be revealed,

281
00:21:12,600 --> 00:21:16,400
a comparative science of
geochemistry must be launched."

282
00:21:18,033 --> 00:21:20,233
50 years later,
the man who would realize

283
00:21:20,367 --> 00:21:22,800
Schönbein's dream was born.

284
00:21:23,734 --> 00:21:26,133
He was another German-Swiss.

285
00:21:26,266 --> 00:21:29,066
Victor Goldschmidt
was so brilliant,

286
00:21:29,200 --> 00:21:32,567
he was offered a position
here at the University of Oslo

287
00:21:32,700 --> 00:21:35,967
without ever taking a
test or earning a degree.

288
00:21:36,500 --> 00:21:39,934
That was in 1909,
when he was only 21.

289
00:21:40,667 --> 00:21:44,633
Three years later,
he was awarded Norway's
greatest scientific prize.

290
00:21:48,200 --> 00:21:52,333
Victor Goldschmidt saw
the Earth as a single system.

291
00:21:52,467 --> 00:21:55,000
He knew that in order
to get the whole picture,

292
00:21:55,133 --> 00:21:58,767
you couldn't
just know physics,
chemistry, or geology...

293
00:21:59,100 --> 00:22:01,433
you had to know them all.

294
00:22:02,266 --> 00:22:05,066
This was in the early days of
the study of the basic elements.

295
00:22:06,333 --> 00:22:09,133
Goldschmidt applied this new
knowledge to create his own

296
00:22:09,266 --> 00:22:11,033
version of the periodic table,

297
00:22:11,734 --> 00:22:14,100
one that is
still in use today.

298
00:22:14,533 --> 00:22:16,967
It illuminated how crystals
and complex minerals could

299
00:22:17,100 --> 00:22:19,600
be formed from
more basic elements.

300
00:22:19,734 --> 00:22:22,100
Goldschmidt was
discovering how matter evolves

301
00:22:22,233 --> 00:22:26,467
into mountains and
cliffs and canyons.

302
00:22:30,834 --> 00:22:34,100
In 1928, he made a
fateful decision to accept

303
00:22:34,233 --> 00:22:36,333
an appointment at
the University of Göttingen,

304
00:22:36,467 --> 00:22:40,133
in Germany,
where an institute had
been built just for him.

305
00:22:40,500 --> 00:22:44,533
His colleagues
thought these were
his happiest years, until...

306
00:22:44,667 --> 00:22:47,433
(hammering)

307
00:22:50,333 --> 00:22:53,033
1933,

308
00:22:55,900 --> 00:22:58,433
when Adolf Hitler came to power.

309
00:22:59,033 --> 00:23:01,934
Goldschmidt was Jewish,
but not observant.

310
00:23:02,066 --> 00:23:04,400
Hitler changed
all that for him.

311
00:23:04,533 --> 00:23:07,166
He now began to publicly
identify himself with the

312
00:23:07,300 --> 00:23:09,200
local Jewish community.

313
00:23:09,333 --> 00:23:12,200
Hitler made it compulsory
for everyone to list any

314
00:23:12,333 --> 00:23:15,700
Jewish forbearers going
back several generations.

315
00:23:16,233 --> 00:23:18,900
There were those who tried
to conceal a grandfather who

316
00:23:19,033 --> 00:23:21,400
might land them in
a concentration camp.

317
00:23:21,533 --> 00:23:24,433
But Goldschmidt proudly
declared on his forms that all

318
00:23:24,567 --> 00:23:26,967
of his ancestors were Jewish.

319
00:23:27,100 --> 00:23:30,567
Hitler and Hermann Göring,
founder of the Gestapo,

320
00:23:30,700 --> 00:23:32,500
were not amused.

321
00:23:36,400 --> 00:23:37,600
GOLDSCHMIDT: Hmm?

322
00:23:37,734 --> 00:23:39,367
TYSON: They personally sent a
letter to Goldschmidt telling

323
00:23:39,500 --> 00:23:42,367
him he was summarily dismissed
from his university position.

324
00:23:48,266 --> 00:23:51,233
He fled to Norway with
only the clothes on his back.

325
00:23:58,066 --> 00:24:00,767
Goldschmidt concentrated
his research on olivine,

326
00:24:01,233 --> 00:24:03,266
that green jewel
of a mineral left over from

327
00:24:03,400 --> 00:24:05,533
the formation
of the solar system.

328
00:24:06,100 --> 00:24:08,567
He was fascinated by
its power to withstand even

329
00:24:08,700 --> 00:24:11,200
the highest temperatures.

330
00:24:11,734 --> 00:24:14,400
He was the first to speculate
that olivine may have played

331
00:24:14,533 --> 00:24:17,900
a role in setting the
stage for the origin of life.

332
00:24:18,467 --> 00:24:20,800
At the same time, he
wondered about the presence

333
00:24:20,934 --> 00:24:23,300
of olivine
throughout the cosmos.

334
00:24:24,200 --> 00:24:27,633
This was the beginning of
a field called cosmochemistry.

335
00:24:29,400 --> 00:24:32,934
In 1940, when the
Germans invaded Norway,

336
00:24:33,066 --> 00:24:36,734
Goldschmidt took to carrying
a cyanide capsule in his pocket

337
00:24:36,867 --> 00:24:38,900
so that he could kill
himself instantly if the

338
00:24:39,033 --> 00:24:41,400
Gestapo came for him.

339
00:24:41,734 --> 00:24:44,500
When a fellow scientist
asked if he could get one, too,

340
00:24:44,633 --> 00:24:46,533
Goldschmidt answered:

341
00:24:46,667 --> 00:24:50,066
"This poison is for
chemistry professors only.

342
00:24:50,200 --> 00:24:53,900
You, as a physicist,
will have to use a rope."

343
00:24:59,800 --> 00:25:01,166
(knock)

344
00:25:01,300 --> 00:25:02,567
NAZI: Herr Goldschmidt.

345
00:25:02,700 --> 00:25:04,100
TYSON: But when
the Germans arrived,

346
00:25:04,233 --> 00:25:06,467
Goldschmidt kept the
cyanide in his pocket.

347
00:25:07,800 --> 00:25:09,033
NAZI: Goldschmidt.

348
00:25:09,166 --> 00:25:11,600
(speaking in German)

349
00:25:14,100 --> 00:25:16,633
TYSON: He was sent to the
Berg concentration camp before

350
00:25:16,767 --> 00:25:19,233
they were ready to
deport him to Auschwitz,

351
00:25:19,767 --> 00:25:23,500
a place he told
friends that "had not
been highly recommended."

352
00:25:29,967 --> 00:25:31,834
Goldschmidt was too
important a scientist

353
00:25:31,967 --> 00:25:34,700
for the Nazis to exterminate.

354
00:25:34,834 --> 00:25:37,500
He was given the chance of
survival if he would put

355
00:25:37,633 --> 00:25:39,934
his science in the
service of the Reich.

356
00:25:41,033 --> 00:25:44,433
But Goldschmidt dared
to toy with his captors.

357
00:25:44,834 --> 00:25:48,533
He would lead the Germans on
a scientific wild goose chase.

358
00:25:48,667 --> 00:25:52,133
He sent them searching
for nonexistent minerals

359
00:25:52,266 --> 00:25:54,667
and deceived them into
believing these were resources

360
00:25:55,200 --> 00:25:57,834
that would be
critical to the war effort.

361
00:25:58,567 --> 00:26:01,633
His ruse could have been
discovered at any moment,

362
00:26:01,767 --> 00:26:03,800
and that would have meant
certain death in the most

363
00:26:03,934 --> 00:26:06,467
fiendish way possible.

364
00:26:07,734 --> 00:26:11,200
By the end of 1942,
the Norwegian Resistance knew

365
00:26:11,333 --> 00:26:13,734
that Goldschmidt was
in the gravest danger.

366
00:26:14,567 --> 00:26:17,367
They arranged for
him to escape across
the Swedish frontier.

367
00:26:26,266 --> 00:26:28,967
Goldschmidt spent the
rest of the war in Sweden,

368
00:26:29,100 --> 00:26:33,066
and then England, contributing
his knowledge to the Allies.

369
00:26:33,433 --> 00:26:34,967
Always in frail health,

370
00:26:35,100 --> 00:26:38,233
he never recovered from
the hardships of the war.

371
00:26:38,367 --> 00:26:42,567
Victor Goldschmidt
died a year and
a half after it was over.

372
00:26:43,066 --> 00:26:45,467
But during that period,
he wrote a research paper on

373
00:26:45,600 --> 00:26:48,400
the complex organic
molecules that he thought might

374
00:26:48,533 --> 00:26:51,300
have led to the
origin of life on Earth.

375
00:26:51,433 --> 00:26:54,166
And the ideas in that
paper remain central in our

376
00:26:54,300 --> 00:26:57,300
effort to understand
how life came to be.

377
00:27:02,266 --> 00:27:06,467
Goldschmidt never knew that
the generations of geochemists

378
00:27:06,600 --> 00:27:10,300
who came after him would
consider him their founder.

379
00:27:12,433 --> 00:27:15,800
Among his last
wishes was a simple request.

380
00:27:16,767 --> 00:27:18,834
He wanted to be cremated and

381
00:27:18,967 --> 00:27:22,133
to have his ashes
encased in an urn...

382
00:27:22,667 --> 00:27:26,467
made of the thing he believed
to be the stuff of life,

383
00:27:27,567 --> 00:27:30,600
his beloved olivine.

384
00:27:31,533 --> 00:27:34,433
The universe makes galaxies.

385
00:27:34,567 --> 00:27:37,200
Galaxies make stars.

386
00:27:37,333 --> 00:27:40,467
Stars make worlds.

387
00:27:40,967 --> 00:27:44,767
Are there other
Lost Cities of Life
in the cosmos?

388
00:27:45,467 --> 00:27:54,934
Come with me.

389
00:27:55,066 --> 00:27:58,133
TYSON: There are dues to be
paid for cosmic citizenship.

390
00:27:58,600 --> 00:28:01,166
As a spacefaring species,
you have to worry about

391
00:28:01,300 --> 00:28:04,567
contaminating the worlds you
visit and about bringing

392
00:28:04,700 --> 00:28:08,567
back alien stowaways
that might pose a danger
to your home world.

393
00:28:09,734 --> 00:28:13,333
There are protocols
for planetary protection.

394
00:28:13,767 --> 00:28:17,700
NASA designates
five categories
of worlds in the cosmos.

395
00:28:19,166 --> 00:28:22,400
Earth's moon, for instance,
is a Category-1 world...

396
00:28:23,300 --> 00:28:26,967
a place so lifeless,
we pose no threat to it,

397
00:28:27,100 --> 00:28:30,567
and it poses no threat to us.

398
00:28:31,266 --> 00:28:35,900
The riskiest of all is a
Restricted Category-5 world,

399
00:28:36,033 --> 00:28:38,667
like this one, Mars.

400
00:28:39,100 --> 00:28:41,300
The conditions
for indigenous life...

401
00:28:41,433 --> 00:28:45,133
in the past,
or even now, hidden in
some subsurface recess,

402
00:28:45,900 --> 00:28:48,000
are not beyond possible.

403
00:28:48,133 --> 00:28:50,133
We have to be very careful,

404
00:28:50,266 --> 00:28:54,433
for our own sake and
for the life that could
conceivably be there.

405
00:28:55,667 --> 00:28:58,934
The Restricted Cat-5
designation is a recognition

406
00:28:59,066 --> 00:29:01,200
of life's genius for escape.

407
00:29:01,333 --> 00:29:04,533
It applies to sample return
missions from those worlds

408
00:29:04,667 --> 00:29:07,133
where life may
have gotten started...

409
00:29:07,633 --> 00:29:11,600
those worlds that may have,
or once may have had,

410
00:29:11,734 --> 00:29:15,433
Lost Cities of Life lying
at the bottom of their seas.

411
00:29:16,300 --> 00:29:19,567
But in a sense, our
robot emissaries themselves...

412
00:29:19,700 --> 00:29:21,767
our landers,
rovers and orbiters,

413
00:29:21,900 --> 00:29:25,100
are a manifestation of
life's relentless imperative

414
00:29:25,233 --> 00:29:29,100
to seek out and
take new territory, and
this means that some of

415
00:29:29,233 --> 00:29:33,000
our emissaries have
to be destroyed as soon
as their missions are over.

416
00:29:34,700 --> 00:29:37,066
Like, poor Juno.

417
00:29:37,600 --> 00:29:39,867
After a multiyear
reconnaissance of Jupiter,

418
00:29:40,000 --> 00:29:42,700
NASA is sending
her to her death.

419
00:29:43,033 --> 00:29:45,166
Not because they were
worried about Jupiter.

420
00:29:45,300 --> 00:29:47,934
There's hardly any chance
that one of our spacecraft

421
00:29:48,066 --> 00:29:51,633
could compromise future
investigations of
the giant gas planet.

422
00:29:52,400 --> 00:29:55,667
Any rogue microbe would
catch a downdraft and sink where

423
00:29:55,800 --> 00:29:58,633
it would be broiled
by the scathing temperatures.

424
00:29:59,066 --> 00:30:02,233
That's why Jupiter's
only a Category-2 world.

425
00:30:02,367 --> 00:30:05,667
But one of Jupiter's moons
is a Restricted Cat-5,

426
00:30:06,266 --> 00:30:08,900
and NASA can't take
the chance that Juno might

427
00:30:09,033 --> 00:30:11,200
inadvertently crash into it.

428
00:30:12,467 --> 00:30:15,900
Europa is another one of only
three Restricted Cat-5 worlds

429
00:30:16,033 --> 00:30:18,767
in the solar system,
and one of Jupiter's 80

430
00:30:18,900 --> 00:30:21,633
and still counting, moons.

431
00:30:33,567 --> 00:30:36,500
Michael Faraday discovered
Earth's magnetic field,

432
00:30:36,633 --> 00:30:38,767
and there's one
around Jupiter, too.

433
00:30:38,900 --> 00:30:41,166
We can see it if we switch
from looking at Jupiter in

434
00:30:41,300 --> 00:30:44,033
visible light to looking
at it in radio waves.

435
00:30:45,900 --> 00:30:50,633
Jupiter's magnetic
field is much stronger
and 18,000 times bigger.

436
00:30:51,300 --> 00:30:54,834
It's a gigantic trap
for charged particles
that are the solar wind.

437
00:30:55,500 --> 00:30:58,300
That's one of the things
that lights up the aurora,

438
00:30:58,433 --> 00:31:00,900
the northern and southern
Lights on Jupiter,

439
00:31:01,200 --> 00:31:04,166
and it does the
same thing on Earth.

440
00:31:08,900 --> 00:31:11,600
Imagine what it's like for
little Europa and her sister

441
00:31:11,734 --> 00:31:15,100
moons to live so close
to the king of the Planets.

442
00:31:15,867 --> 00:31:18,767
Massive Jupiter holds Europa
to him in a gravitational

443
00:31:18,900 --> 00:31:22,467
embrace so powerful
that in four billion years,

444
00:31:22,600 --> 00:31:25,834
she has never been able to
turn her face away from his.

445
00:31:27,567 --> 00:31:30,533
Jupiter's hold on her
is so fierce that it
tears her skin apart.

446
00:31:32,133 --> 00:31:34,633
See those broad scars?

447
00:31:34,767 --> 00:31:36,433
Watch them closely and listen.

448
00:31:36,700 --> 00:31:39,233
(colliding rocks)

449
00:31:40,100 --> 00:31:44,200
That's the sound of a world
being gravitationally tormented.

450
00:31:44,333 --> 00:31:48,200
It's called tidal flexing,
and it's not just Jupiter,

451
00:31:48,967 --> 00:31:51,767
her sister moons
pull on her, too.

452
00:31:52,367 --> 00:31:55,767
We are half a billion
miles from the sun's warmth,

453
00:31:55,900 --> 00:31:58,667
five times farther
away than Earth is,

454
00:31:58,800 --> 00:32:02,166
but this tidal flexing
keeps Europa toasty inside.

455
00:32:03,700 --> 00:32:06,433
Beneath her chaotic surface,
there's an ocean ten times

456
00:32:06,567 --> 00:32:09,900
deeper than the
deepest seas on Earth.

457
00:32:25,066 --> 00:32:28,233
♪ ♪

458
00:32:28,367 --> 00:32:32,867
We're on our way to
another Restricted Cat-5 world.

459
00:32:33,000 --> 00:32:34,333
No, not Saturn.

460
00:32:34,467 --> 00:32:36,767
Saturn's another Cat-2.

461
00:32:38,033 --> 00:32:41,934
Any life passing
through those cloud belts
wouldn't have a chance.

462
00:32:42,433 --> 00:32:44,734
They're made
mostly of ammonia.

463
00:32:44,867 --> 00:32:47,400
Below them are
bands of water vapor.

464
00:32:47,533 --> 00:32:52,333
In one of our future
voyages, we'll go there
at a terrible cost.

465
00:32:54,266 --> 00:32:55,834
It's not Titan, either.

466
00:32:55,967 --> 00:32:58,467
Titan's another
Category-2 world.

467
00:32:58,600 --> 00:33:01,266
Just as with Saturn, the
possibility of us interfering

468
00:33:01,400 --> 00:33:04,900
with the life that
might be there is too remote.

469
00:33:05,233 --> 00:33:07,266
Of course, there's always
the chance that Titan life

470
00:33:07,400 --> 00:33:10,066
is stranger than
our ability to imagine.

471
00:33:10,200 --> 00:33:12,667
Even if that's the case,
there is little likelihood

472
00:33:12,800 --> 00:33:15,667
that any form of
Earth life could harm it.

473
00:33:19,333 --> 00:33:23,533
There she is, our
Restricted Cat-5 world.

474
00:33:34,400 --> 00:33:37,667
TYSON: There's a
world in our solar system
that may harbor life.

475
00:33:39,567 --> 00:33:42,400
You're looking at two of
the first people ever to see it.

476
00:33:43,433 --> 00:33:46,100
William Herschel saw
farther into the deep waters

477
00:33:46,233 --> 00:33:48,633
of the cosmic ocean
than anyone before him.

478
00:33:49,734 --> 00:33:52,800
His son, John,
would also become
a distinguished astronomer.

479
00:33:54,000 --> 00:33:57,967
But tonight is back
when John was a child
in the summer of 1802.

480
00:33:59,400 --> 00:34:02,367
That's when we first met
them on an earlier voyage.

481
00:34:03,500 --> 00:34:05,633
WILLIAM: John, I want
to show you something.

482
00:34:06,367 --> 00:34:08,467
Come with me.

483
00:34:13,300 --> 00:34:16,100
TYSON: This was then the
largest telescope on Earth

484
00:34:16,233 --> 00:34:18,066
and would be for 50 years.

485
00:34:21,900 --> 00:34:24,834
CAROLINE: Well,
what have we here? Hmm?

486
00:34:24,967 --> 00:34:28,000
Isn't it awfully late
for a little boy to be up?

487
00:34:28,600 --> 00:34:31,633
JOHN: Father has promised
to show me something,
Aunt Caroline.

488
00:34:31,767 --> 00:34:33,834
TYSON: William's sister,
Caroline Herschel,

489
00:34:33,967 --> 00:34:37,266
was a world-renowned
astronomer in her own right.

490
00:34:37,400 --> 00:34:40,800
She was the first woman
anywhere on Earth to be paid

491
00:34:40,934 --> 00:34:43,066
for being a scientist.

492
00:34:45,100 --> 00:34:47,200
She was just four-foot-three.

493
00:34:47,333 --> 00:34:48,934
When Caroline
was ten years old,

494
00:34:49,066 --> 00:34:50,834
she was stricken with typhus.

495
00:34:50,967 --> 00:34:54,533
She lost part of
the vision in her left
eye and stopped growing.

496
00:34:54,900 --> 00:34:59,033
And yet, she
defied the limitations
of her time to a point.

497
00:35:01,567 --> 00:35:03,567
Caroline had just
published her work in the

498
00:35:03,700 --> 00:35:06,667
"Catalogue of Nebulae
and Clusters of Stars,"

499
00:35:07,166 --> 00:35:09,967
but it was under her
brother William's name.

500
00:35:10,700 --> 00:35:13,734
It was 1802, after all.

501
00:35:14,133 --> 00:35:16,700
Her nephew, John, would
grow up to build on her

502
00:35:16,834 --> 00:35:19,834
work and create the
"New General Catalogue."

503
00:35:21,000 --> 00:35:26,400
Many astronomical bodies
are still designated
by their NGC number today.

504
00:35:30,767 --> 00:35:35,133
WILLIAM: A few more degrees
east and a degree north.

505
00:35:35,567 --> 00:35:36,934
ASSISTANT: Yes, sir.

506
00:35:42,166 --> 00:35:46,367
WILLIAM: Stop, stop!
There she is.

507
00:35:49,500 --> 00:35:52,467
JOHN: Father! I've
never seen that before.

508
00:35:53,066 --> 00:35:54,767
Is it a new star?

509
00:35:54,900 --> 00:35:58,700
WILLIAM: No, son,
it's a new moon.

510
00:35:58,967 --> 00:36:01,066
I call it Saturn Two.

511
00:36:01,200 --> 00:36:05,000
JOHN: Oh, but Father,
we must think of a
better name than that.

512
00:36:05,800 --> 00:36:08,400
WILLIAM: That's
your job, my boy.

513
00:36:08,533 --> 00:36:11,300
TYSON: And John would do
exactly as his father asked.

514
00:36:11,433 --> 00:36:15,033
He named the moon Enceladus,
after the Giant in Greek

515
00:36:15,166 --> 00:36:18,166
mythology who was the son
of the Earth and the Sky.

516
00:36:19,467 --> 00:36:22,600
Enceladus fought the goddess
Athena in an epic struggle

517
00:36:22,734 --> 00:36:24,533
for control of the universe.

518
00:36:34,133 --> 00:36:36,467
You don't have to be an
astrobiologist to know at

519
00:36:36,600 --> 00:36:39,600
first glance that life
is everywhere on Earth.

520
00:36:41,266 --> 00:36:45,233
It's changed virtually
every square inch of the place.

521
00:36:45,600 --> 00:36:47,934
From an alien point of view,
Earth would certainly have a

522
00:36:48,066 --> 00:36:51,100
Restricted Cat-5 status.

523
00:36:52,467 --> 00:36:55,600
But Enceladus keeps its
secrets hidden deep inside.

524
00:37:10,100 --> 00:37:14,767
♪ ♪

525
00:37:21,834 --> 00:37:25,300
Those geysers of ice and
water vapor are shooting out

526
00:37:25,433 --> 00:37:28,567
of Enceladus
at 800 miles per hour.

527
00:37:29,166 --> 00:37:32,667
They're this moon's
contribution to the outermost
so-called "E" ring of Saturn.

528
00:37:34,734 --> 00:37:36,066
But there's a
lot more in them...

529
00:37:36,200 --> 00:37:38,834
nitrogen, ammonia, methane.

530
00:37:40,300 --> 00:37:42,967
And where there's methane,
there may be olivine.

531
00:37:44,100 --> 00:37:47,967
Enceladus has been at this
for at least 100 million years.

532
00:37:48,533 --> 00:37:52,066
It could keep cranking
out water for another
nine billion years.

533
00:37:54,667 --> 00:37:56,667
Where's all that
water coming from?

534
00:38:15,734 --> 00:38:19,467
The blue snowflakes plummet at
more than 1,000 miles per hour.

535
00:38:20,367 --> 00:38:23,934
We've come here to the
southern hemisphere because

536
00:38:24,066 --> 00:38:26,200
that's where the
ice crust is thinnest.

537
00:38:26,533 --> 00:38:29,567
It's only a
couple of miles thick.

538
00:38:31,867 --> 00:38:34,266
That's why it's the best
possible place to gain access

539
00:38:34,400 --> 00:38:36,834
to the underground ocean.

540
00:38:42,200 --> 00:38:44,300
Okay, now's the
time for a warning:

541
00:38:44,433 --> 00:38:47,600
What you see here is
entirely based on evidence.

542
00:38:47,734 --> 00:38:49,934
That global ocean,
the crazy curtain of geysers,

543
00:38:51,333 --> 00:38:52,900
that weird snow
at the surface...

544
00:38:53,800 --> 00:38:55,233
it's all real.

545
00:38:55,367 --> 00:38:57,300
We have multiple
observations from the Cassini

546
00:38:57,433 --> 00:39:00,734
mission telling us that this
is what awaits us on Enceladus.

547
00:39:03,367 --> 00:39:06,967
But we're about to enter the
realm of informed speculation.

548
00:39:07,667 --> 00:39:10,934
This is what the leading space
scientists think we might find

549
00:39:11,066 --> 00:39:15,367
when we send a spacecraft
to dive straight into
the heart of Enceladus.

550
00:39:17,133 --> 00:39:19,834
(geyser erupting)

551
00:39:33,166 --> 00:39:35,934
When water up here is
exposed to the vacuum of space,

552
00:39:36,800 --> 00:39:39,934
it turns to snow.

553
00:39:49,367 --> 00:39:52,400
And that scum
is the stuff of life...

554
00:39:52,533 --> 00:39:54,867
organic molecules.

555
00:39:55,000 --> 00:39:58,700
It makes you wonder what could
be waiting for us down below.

556
00:39:59,734 --> 00:40:01,333
And that's a
long way from here,

557
00:40:01,467 --> 00:40:04,266
because we're in an ocean
that's about ten times deeper

558
00:40:04,400 --> 00:40:06,800
than the oceans of Earth.

559
00:40:09,900 --> 00:40:12,266
Very promising.

560
00:40:12,400 --> 00:40:16,100
That's carbon and hydrogen,
and the pH of the water is

561
00:40:16,233 --> 00:40:18,200
just like the
early ocean on Earth.

562
00:40:36,934 --> 00:40:43,266
♪ ♪

563
00:41:01,367 --> 00:41:04,100
♪ ♪

564
00:41:04,233 --> 00:41:07,200
Why would this City of Life
be larger than the one at the

565
00:41:07,333 --> 00:41:09,300
bottom of the ocean on Earth?

566
00:41:13,166 --> 00:41:15,500
Maybe it's because the
gravity on Enceladus is so

567
00:41:15,633 --> 00:41:17,800
much weaker than
it is on Earth.

568
00:41:18,433 --> 00:41:21,867
With less gravity,
the towers are lighter,

569
00:41:22,000 --> 00:41:24,233
and they can grow taller.

570
00:41:27,233 --> 00:41:29,033
The currents are strong,

571
00:41:29,166 --> 00:41:31,433
and they may have
toppled some of the towers.

572
00:41:44,033 --> 00:41:46,700
Victor Goldschmidt's olivine.

573
00:41:47,500 --> 00:41:51,100
The rocks have
made a place for life.

574
00:41:53,133 --> 00:41:56,333
But has life had
enough time to take hold?

575
00:41:57,533 --> 00:42:01,967
All I know is,
never underestimate
the escape artist.

576
00:42:22,367 --> 00:42:25,100
You know, it's a
funny thing about us.

577
00:42:25,233 --> 00:42:27,367
We think we're the story.

578
00:42:27,500 --> 00:42:30,600
We're the end all
and be all of the cosmos.

579
00:42:31,100 --> 00:42:34,700
And yet, for all we know,
we're just the by-product of

580
00:42:34,834 --> 00:42:37,233
geochemical forces...

581
00:42:37,367 --> 00:42:41,233
ones that are unfolding
throughout the universe.

582
00:42:50,533 --> 00:42:54,967
Galaxies make stars,
stars make worlds,

583
00:43:00,333 --> 00:43:04,667
and for all we know,
planets and moons make life.

584
00:43:07,967 --> 00:43:10,967
Does that make
life less wondrous?

585
00:43:11,767 --> 00:43:13,667
Or more?

586
00:43:14,533 --> 00:43:16,133
Captioned by
Cotter Captioning Services.