All language subtitles for cosmos.possible.worlds.s01e03

We are a long way
from home, and from our time.

This was our Milky Way
when the galaxy was young

and more fertile
than it is today.

Back then, she birthed 30 times
as many stars as she does now...

a firestorm of star creation.

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

We're on the
planet of another star,

one with an ideal view of
the Milky Way galaxy's

chaotic stellar nursery.

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

and that may be one
of the reasons we exist.

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

there was time...

another five billion years,
for those dead stars to bequeath

their heavier elements to us.

These elements enriched
and nurtured the formation

of the planets and
moons of our solar system.

And we ourselves are
made of that star stuff.

Those blazing pink clouds of
hydrogen gas are the swaddling

of countless new-born stars.

See those bright blue splashes?

They're clusters of
slightly older sibling stars.

Gravity's embrace will
transform this amorphous

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

Our sun is born.

The star endows her
surrounding worlds

with precious minerals,
diamonds and green olivine...

a mineral that will play
a major role in our story.

The stars make planets,
moons and comets.

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

These future planets and moons
are awash with organic molecules...

the chemical
building blocks of life.

This is their inheritance
from the deaths of other stars.

Does the cosmos give
rise to life as naturally

as it makes stars and worlds?

This is our voyage to
the heart of that mystery.

Long, long ago,
when our world was young,

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

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

but there was no life
on this world back then.

So who built these
submarine skyscrapers?

Nature did.

She made them with carbon
dioxide and the same minerals

she uses to make
seashells and pearls...

calcium carbonate.

But these soaring towers
were nothing compared to what

happened beneath them.

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

Doesn't look like much, does it?

But just wait.

Our restless
Mother Earth cracked open,

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

getting richer in
organic molecules and minerals,

including a green
jewel called olivine.

This mix of water and
minerals got so hot that it

shot out of
her with great force.

The mixture became trapped
in the pores of the carbonate

rocks that would
later become her towers.

These pores were incubators,
safe places where the organic

molecules could
become more concentrated.

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

It was the beginning,
at least in our little

part of the cosmos,
of an enduring collaboration

between the minerals of earth,

the rocks and life.

See those snaky cracks?

That's how this
process got its name.

Serpentinization.

It's the evidence for
the conversion of water and

carbon dioxide into
hydrogen and methane...

the organic molecules that
fueled this earthshaking event.

Those scientists who
search for life on other worlds,

they used to say,
"follow the water,"

because water is the most
basic requirement for life.

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

because serpentinization
is so closely associated with

the processes that
make life possible.

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

At this scale,
these caves look vast,

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

These jewels are the
organic molecules which are,

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

In order to turn these
inanimate jewels into jewelry,

the stuff of life,
it takes energy.

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

The energy came from the
reaction between the alkaline

water trapped within the towers

and the acidic
water of the ocean.

That ancient treasure
chest filled with rings and

bracelets and necklaces,

longer and more
complex molecules,

until the greatest
treasure of all...

Life.

We think it was that
chemical reaction that provided

the energy that
powered the first cell.

That was the spark that
electrified the building blocks of life

into something alive.

Over time, the towers decayed,

making it possible for
the fledgling life within them

to escape and evolve.

What you've just seen is
the most plausible scientific

creation myth we have
today for the origin of life.

This hypothesis
required the reunification

of four long
separated scientific fields:

biology, chemistry,
physics and geology.

We think life first
took hold in the rocks.

And from day one,
life was an escape artist,

always wanting to break free,
to conquer new worlds.

Even the great big
ocean couldn't contain it.

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

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

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

Back when the planet
was an ocean world,

with waters bloodred with iron.

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

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

There came a day of reckoning,

when life nearly
destroyed itself.

The Cosmic Calendar
is a way for us to wrap our

heads around the
vastness of time.

To grasp the
history of the cosmos,

from the birth of our
universe to this very moment,

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

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

Every day represents
nearly 40 million years.

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

almost 14 billion years ago.

Nothing really happened
in our neck of the universe

until about three
billion years later...

March 15 of the cosmic year,

when our Milky Way
galaxy began to form.

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

It was August 31st
on the Cosmic Calendar.

Jupiter and the other planets,
including our own,

would soon follow.

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

September 21st on
the Cosmic Calendar,

when we believe life began.

The atmosphere was
a hydrocarbon smog.

No oxygen to breathe
and no one to breathe it.

We've only recently begun
to appreciate how powerfully

life has shaped the planet.

When we think about the
ways life has changed Earth,

the first things that come
to mind are the green expanses

of forests, and
the sprawling cities.

But life began transforming
the planet long before there

were any such things.

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

life had become a
global phenomenon thanks to

a champion that to this
day has never been vanquished.

I give you the cyanobacteria.

In business for
2.7 billion years,

cyanobacteria can
make a living anywhere.

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

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

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

taking in carbon dioxide
and giving back oxygen,

turned the sky blue.

But the cyanobacteria
didn't just change the sky,

they reached into
the very rocks themselves

and changed them, too.

Oxygen rusted the iron,

working its magic
on the minerals.

Of the 5,000 kinds
of minerals on Earth,

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

But here comes
that day of reckoning.

Cyanobacteria were the
dominant life-form on this planet,

wreaking havoc
wherever they went,

changing the landscape,
the water and the skies.

This was 2.3
billion years ago,

or late October on
the Cosmic Calendar.

But the cyanobacteria shared
the planet with other beings:

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

cyanobacteria had begun to
pollute the Earth with oxygen.

For the anaerobes,
oxygen was poison,

but the cyanobacteria
wouldn't stop loading up

the atmosphere with the stuff.

For the anaerobes,
and nearly all of the other

life on Earth, it
was an oxygen apocalypse.

The lone survivors among
the anaerobes were those

who sought refuge
at the bottom of the sea,

deep in the sediment where
the oxygen could not reach them.

The cyanobacteria acted
like oxygen-pumping machines.

They continued in overdrive,
and 400 million years later,

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

Remember those serpentinized
rocks at the bottom of the sea

that were cranking out
hydrogen and methane?

Methane is a
powerful greenhouse gas,

and back then it was the main
thing keeping the planet warm.

But once again, the oxygen
produced by life shook things up.

It gobbled up the methane,
producing carbon dioxide,

a much less
potent greenhouse gas...

meaning it was not as
efficient at trapping heat

in Earth's atmosphere.

Earth's temperature
began to plunge.

Life, the escape artist,
busted out of the icy death grip

that entombed the planet.

The corpses of dead bacteria
left behind a planetwide

reservoir of carbon dioxide.

Volcanoes pumped the carbon dioxide
in huge quantities into the atmosphere,

warming the planet
and melting the ice.

Over the next billion years,

life and the rocks
continued their elaborate dance,

taking the planet
through freezes and thaws.

Then, 540 million years ago,
something wondrous happened.

Life, which had been all
about microbes and simple

multicellular creatures,
suddenly took off in what's

called the Cambrian Explosion.

Life grew legs,
eyes, gills, teeth,

and rapidly began to evolve
the forms of its stunning diversity.

We don't yet know what it was
that allowed life to diversify

so dramatically, but we
have some plausible theories.

It could have been all
those calcium minerals in

the seawater that
came from the volcanoes.

Life had grown a
backbone and put on a shell.

It had found a way to
collaborate with the rocks

to make its own armor.

Now life could grow larger and
venture forth into new territories.

Or maybe it was the
protection afforded by the

canopy built by
the cyanobacteria.

The oxygenation of the
atmosphere created the ozone layer.

This made it possible
for life to break out of the

safety of the oceans
and inhabit the land without

being assaulted by the
sun's deadly ultraviolet rays.

For billions of years,
all life could do was ooze.

Now, life began to
swim, run, jump and fly.

Life, the escape artist,
had gotten so good at wriggling

out of every confine, no
prison on Earth could hold it.

And there will come a day,

when life would
even escape from Earth.

Life will not be contained.

Retracing life's odyssey
back to the very beginning

required a new kind of science,

one that
reunited the disciplines.

The man who founded this
new approach also happened

to be an escape artist himself.

He fled history's
most implacable killers,

right here in this forest,
jesting at his tormentors

every step of the way.

Remember this place?

It's London's Royal Institution,

where Michael Faraday
spent his life.

Back in his time, in the
first half of the 19th century,

the intimate relationship
between life and the rocks

had yet to be discovered.

Before science could
tackle the origin of life,

it had to change.

This development was
foretold by a scientist

whose gifts to the world,
were decidedly mixed.

Christian Friedrich Schönbein
was a German-Swiss chemist who

was conducting an experiment
on using electricity to reduce

water into its two
chemical constituents,

oxygen and hydrogen.

Schönbein thought he
smelled something familiar,

something like the
air after a thunderstorm.

Schönbein had discovered ozone.

Remember, that's the layer
in the atmosphere that made

it possible for our distant
ancestors to leave the water

for the land, and it
still protects us from

ultraviolet rays to this day.

Schönbein loved to experiment.

So much so that his wife
famously exacted a promise

from him not to use their
kitchen as his laboratory.

Oh.

Schönbein had just invented a
new weapon of mass destruction.

A chemical explosive
more powerful than gunpowder.

Upon further refinement,
gun cotton would industrialize

warfare on a horrendous scale.

But it was also Schönbein
who had a prophetic vision of

a new field of science.

He wrote in 1838:

"Before the mystery of
the genesis of our planets"

and their inorganic
matter can be revealed,

"a comparative science of
geochemistry must be launched."

50 years later,
the man who would realize

Schönbein's dream was born.

He was another German-Swiss.

Victor Goldschmidt
was so brilliant,

he was offered a position
here at the University of Oslo

without ever taking a
test or earning a degree.

That was in 1909,
when he was only 21.

Three years later, he was awarded
Norway's greatest scientific prize.

Victor Goldschmidt saw
the Earth as a single system.

He knew that in order
to get the whole picture,

you couldn't just know
physics, chemistry, or geology...

you had to know them all.

This was in the early days of
the study of the basic elements.

Goldschmidt applied this new
knowledge to create his own

version of the periodic table,

one that is still in use today.

It illuminated how crystals
and complex minerals could

be formed from
more basic elements.

Goldschmidt was
discovering how matter evolves

into mountains and
cliffs and canyons.

In 1928, he made a
fateful decision to accept

an appointment at
the University of Göttingen,

in Germany, where an institute
had been built just for him.

His colleagues thought these
were his happiest years, until...

1933,

when Adolf Hitler came to power.

Goldschmidt was Jewish,
but not observant.

Hitler changed all that for him.

He now began to publicly
identify himself with the

local Jewish community.

Hitler made it compulsory
for everyone to list any

Jewish forbearers going
back several generations.

There were those who tried
to conceal a grandfather who

might land them in
a concentration camp.

But Goldschmidt proudly
declared on his forms that all

of his ancestors were Jewish.

Hitler and Hermann Göring,
founder of the Gestapo,

were not amused.

Hmm?

They personally sent a
letter to Goldschmidt telling

him he was summarily dismissed
from his university position.

He fled to Norway with
only the clothes on his back.

Goldschmidt concentrated
his research on olivine,

that green jewel
of a mineral left over from

the formation
of the solar system.

He was fascinated by
its power to withstand even

the highest temperatures.

He was the first to speculate
that olivine may have played

a role in setting the
stage for the origin of life.

At the same time, he
wondered about the presence

of olivine
throughout the cosmos.

This was the beginning of
a field called cosmochemistry.

In 1940, when the
Germans invaded Norway,

Goldschmidt took to carrying
a cyanide capsule in his pocket

so that he could kill
himself instantly if the

Gestapo came for him.

When a fellow scientist
asked if he could get one, too,

Goldschmidt answered:

"This poison is for
chemistry professors only.

You, as a physicist,
will have to use a rope."

Herr Goldschmidt.

But when the Germans arrived,

Goldschmidt kept the
cyanide in his pocket.

Goldschmidt.

He was sent to the
Berg concentration camp before

they were ready to
deport him to Auschwitz,

a place he told friends that "had
not been highly recommended."

Goldschmidt was too
important a scientist

for the Nazis to exterminate.

He was given the chance of
survival if he would put

his science in the
service of the Reich.

But Goldschmidt dared
to toy with his captors.

He would lead the Germans on
a scientific wild goose chase.

He sent them searching
for nonexistent minerals

and deceived them into
believing these were resources

that would be
critical to the war effort.

His ruse could have been
discovered at any moment,

and that would have meant
certain death in the most

fiendish way possible.

By the end of 1942,
the Norwegian Resistance knew

that Goldschmidt was
in the gravest danger.

They arranged for him to escape
across the Swedish frontier.

Goldschmidt spent the
rest of the war in Sweden,

and then England, contributing
his knowledge to the Allies.

Always in frail health,

he never recovered from
the hardships of the war.

Victor Goldschmidt died a
year and a half after it was over.

But during that period,
he wrote a research paper on

the complex organic
molecules that he thought might

have led to the
origin of life on Earth.

And the ideas in that
paper remain central in our

effort to understand
how life came to be.

Goldschmidt never knew that
the generations of geochemists

who came after him would
consider him their founder.

Among his last
wishes was a simple request.

He wanted to be cremated and

to have his ashes
encased in an urn...

made of the thing he believed
to be the stuff of life,

his beloved olivine.

The universe makes galaxies.

Galaxies make stars.

Stars make worlds.

Are there other Lost
Cities of Life in the cosmos?

Come with me.

There are dues to be
paid for cosmic citizenship.

As a spacefaring species,
you have to worry about

contaminating the worlds you
visit and about bringing

back alien stowaways that might
pose a danger to your home world.

There are protocols
for planetary protection.

NASA designates five
categories of worlds in the cosmos.

Earth's moon, for instance,
is a Category-1 world...

a place so lifeless,
we pose no threat to it,

and it poses no threat to us.

The riskiest of all is a
Restricted Category-5 world,

like this one, Mars.

The conditions
for indigenous life...

in the past, or even now,
hidden in some subsurface recess,

are not beyond possible.

We have to be very careful,

for our own sake and for the life
that could conceivably be there.

The Restricted Cat-5
designation is a recognition

of life's genius for escape.

It applies to sample return
missions from those worlds

where life may
have gotten started...

those worlds that may have,
or once may have had,

Lost Cities of Life lying
at the bottom of their seas.

But in a sense, our
robot emissaries themselves...

our landers,
rovers and orbiters,

are a manifestation of
life's relentless imperative

to seek out and take new territory,
and this means that some of

our emissaries have to be destroyed
as soon as their missions are over.

Like, poor Juno.

After a multiyear
reconnaissance of Jupiter,

NASA is sending
her to her death.

Not because they were
worried about Jupiter.

There's hardly any chance
that one of our spacecraft

could compromise future
investigations of the giant gas planet.

Any rogue microbe would
catch a downdraft and sink where

it would be broiled
by the scathing temperatures.

That's why Jupiter's
only a Category-2 world.

But one of Jupiter's moons
is a Restricted Cat-5,

and NASA can't take
the chance that Juno might

inadvertently crash into it.

Europa is another one of only
three Restricted Cat-5 worlds

in the solar system,
and one of Jupiter's 80

and still counting, moons.

Michael Faraday discovered
Earth's magnetic field,

and there's one
around Jupiter, too.

We can see it if we switch
from looking at Jupiter in

visible light to looking
at it in radio waves.

Jupiter's magnetic field is much
stronger and 18,000 times bigger.

It's a gigantic trap for charged
particles that are the solar wind.

That's one of the things
that lights up the aurora,

the northern and southern
Lights on Jupiter,

and it does the
same thing on Earth.

Imagine what it's like for
little Europa and her sister

moons to live so close
to the king of the Planets.

Massive Jupiter holds Europa
to him in a gravitational

embrace so powerful
that in four billion years,

she has never been able to
turn her face away from his.

Jupiter's hold on her is so
fierce that it tears her skin apart.

See those broad scars?

Watch them closely and listen.

That's the sound of a world
being gravitationally tormented.

It's called tidal flexing,
and it's not just Jupiter,

her sister moons
pull on her, too.

We are half a billion
miles from the sun's warmth,

five times farther
away than Earth is,

but this tidal flexing
keeps Europa toasty inside.

Beneath her chaotic surface,
there's an ocean ten times

deeper than the
deepest seas on Earth.

We're on our way to
another Restricted Cat-5 world.

No, not Saturn.

Saturn's another Cat-2.

Any life passing through those
cloud belts wouldn't have a chance.

They're made mostly of ammonia.

Below them are
bands of water vapor.

In one of our future voyages,
we'll go there at a terrible cost.

It's not Titan, either.

Titan's another
Category-2 world.

Just as with Saturn, the
possibility of us interfering

with the life that
might be there is too remote.

Of course, there's always
the chance that Titan life

is stranger than
our ability to imagine.

Even if that's the case,
there is little likelihood

that any form of
Earth life could harm it.

There she is, our
Restricted Cat-5 world.

There's a world in our solar
system that may harbor life.

You're looking at two of
the first people ever to see it.

William Herschel saw
farther into the deep waters

of the cosmic ocean
than anyone before him.

His son, John, would also
become a distinguished astronomer.

But tonight is back when John
was a child in the summer of 1802.

That's when we first met
them on an earlier voyage.

John, I want
to show you something.

Come with me.

This was then the
largest telescope on Earth

and would be for 50 years.

Well,
what have we here? Hmm?

Isn't it awfully late
for a little boy to be up?

Father has promised to show
me something, Aunt Caroline.

William's sister,
Caroline Herschel,

was a world-renowned
astronomer in her own right.

She was the first woman
anywhere on Earth to be paid

for being a scientist.

She was just four-foot-three.

When Caroline was ten years old,

she was stricken with typhus.

She lost part of the vision in
her left eye and stopped growing.

And yet, she defied the
limitations of her time to a point.

Caroline had just
published her work in the

"Catalogue of Nebulae
and Clusters of Stars,"

but it was under her
brother William's name.

It was 1802, after all.

Her nephew, John, would
grow up to build on her

work and create the
"New General Catalogue."

Many astronomical bodies are still
designated by their NGC number today.

A few more degrees
east and a degree north.

Yes, sir.

Stop, stop!
There she is.

Father! I've
never seen that before.

Is it a new star?

No, son, it's a new moon.

I call it Saturn Two.

Oh, but Father, we must
think of a better name than that.

That's your job, my boy.

And John would do
exactly as his father asked.

He named the moon Enceladus,
after the Giant in Greek

mythology who was the son
of the Earth and the Sky.

Enceladus fought the goddess
Athena in an epic struggle

for control of the universe.

You don't have to be an
astrobiologist to know at

first glance that life
is everywhere on Earth.

It's changed virtually
every square inch of the place.

From an alien point of view,
Earth would certainly have a

Restricted Cat-5 status.

But Enceladus keeps its
secrets hidden deep inside.

Those geysers of ice and
water vapor are shooting out

of Enceladus
at 800 miles per hour.

They're this moon's contribution to the
outermost so-called "E" ring of Saturn.

But there's a
lot more in them...

nitrogen, ammonia, methane.

And where there's methane,
there may be olivine.

Enceladus has been at this
for at least 100 million years.

It could keep cranking out water
for another nine billion years.

Where's all that
water coming from?

The blue snowflakes plummet at
more than 1,000 miles per hour.

We've come here to the
southern hemisphere because

that's where the
ice crust is thinnest.

It's only a
couple of miles thick.

That's why it's the best
possible place to gain access

to the underground ocean.

Okay, now's the
time for a warning:

What you see here is
entirely based on evidence.

That global ocean,
the crazy curtain of geysers,

that weird snow
at the surface...

it's all real.

We have multiple
observations from the Cassini

mission telling us that this
is what awaits us on Enceladus.

But we're about to enter the
realm of informed speculation.

This is what the leading space
scientists think we might find

when we send a spacecraft to dive
straight into the heart of Enceladus.

When water up here is
exposed to the vacuum of space,

it turns to snow.

And that scum
is the stuff of life...

organic molecules.

It makes you wonder what could
be waiting for us down below.

And that's a long way from here,

because we're in an ocean
that's about ten times deeper

than the oceans of Earth.

Very promising.

That's carbon and hydrogen,
and the pH of the water is

just like the
early ocean on Earth.

Why would this City of Life
be larger than the one at the

bottom of the ocean on Earth?

Maybe it's because the
gravity on Enceladus is so

much weaker than it is on Earth.

With less gravity,
the towers are lighter,

and they can grow taller.

The currents are strong,

and they may have
toppled some of the towers.

Victor Goldschmidt's olivine.

The rocks have
made a place for life.

But has life had
enough time to take hold?

All I know is, never
underestimate the escape artist.

You know, it's a
funny thing about us.

We think we're the story.

We're the end all
and be all of the cosmos.

And yet, for all we know,
we're just the by-product of

geochemical forces...

ones that are unfolding
throughout the universe.

Galaxies make stars,
stars make worlds,

and for all we know,
planets and moons make life.

Does that make
life less wondrous?

Or more?

Captioned by
Cotter Captioning Services.