All language subtitles for Exploring.Venus.S01E02.WEBRip.x264-ION10_English

(dramatic orchestral music)

- [Narrator] Venus.

At the surface, it's air
is 95% carbon dioxide.

The atmospheric pressure is
like being 900 meters deep

in Earth's oceans.

It's hotter than anywhere
else in the solar system,

except the sun.

And yet, visionary
engineers and scientists

are now unveiling daring new strategies

to explore its tortured landscapes,

to sail it's turbulent, upper-level winds,

to imagine altering its very climate.

(intense instrumental music)

They are taking the first steps

towards settling the
second planet from the sun.

- [Mission Control]
Ignition sequence started.

All engines are started.

We have a liftoff. We have a liftoff.

(indistinct chatter)

(rocket rumbling)

- [Narrator] The early 1970s.

The Space Age was at its peak.

The Apollo astronauts
were exploring the moon.

- [Astronaut] Those
rocks have been waiting

four and a half billion years
for us to come grab 'em.

- [Narrator] Robotic spacecraft
had visited Venus ...

(thunder rumbling)

Mars ...

Mercury ...

and Jupiter, with new missions
on the drawing boards.

And yet, in those heady days,

America and Europe faced a
series of daunting challenges.

The ongoing Cold War ...

unchecked industrial pollution ...

race and class conflict ...

a sudden fuel shortage.

Many thought that only
strict Earth preservation

and laws limiting industry
could save civilization.

(gentle woodwind music)

Meanwhile, a small cadre
of scientists, philosophers

and writers sought answers
in farsighted engineering ...

decentralized information systems ...

which later became the internet
and cellular networks ...

molecular biology ...

which led to gene sequencing

and the promise of nanotechnology ...

and human expansion into space.

They envisioned moon bases ...

cities on Mars ...

grand orbital habitats.

The so-called space colonies would pioneer

a whole new way of living.

(feverish string music)

Future residents in space
would be free to live

by whatever social contracts they chose.

Huge structures assembled
by astronauts and robots,

they would draw upon
resources on the moon ...

- [Astronaut] Stand by for pitch
over. Oh, are we coming in.

- [Narrator] Materials from asteroids ...

and on the free energy of the sun.

These plans consistently
overlooked one planet ...

Venus.

Hellishly hot and enveloped
in a crushing atmosphere,

how could anyone ever live there?

To some visionary thinkers,
Venus held a unique promise,

one that led to one of the most innovative

mission ideas on the books.

(building orchestral music)

A spacecraft carrying astronauts

is bound inward toward the sun.

It slips into low orbit around Venus,

docking with an uncrewed
sister ship sent months before.

One will de-orbit,
protected by an arrow shell,

as it bleeds speed into heat.

(booming)

A parachute further slows the vehicle.

But it isn't heading for a landing.

Instead of continuing to the surface,

it deploys and inflating envelope,

an airship up to 130 meters in length.

The High-Altitude Venus
Operational Concept, HAVOC.

Its crew sales for about 30 Earth days,

navigating in the fast wins,

suspended beneath an inflated
envelope of helium gas.

Circling the planet, they deploy probes

to learn about its atmosphere and geology.

They send out a fleet of
small robotic balloons

to dip down into the
hostile, lower atmosphere.

(dramatic orchestral music)

Their studies complete, the crew ascends

to their transport ship in orbit.

Then, kicked off by a powerful rocket,

they escape Venus's
nearly Earth-level gravity

and make the 100-day
journey back to Earth.

HAVOC-style missions would set the stage

for a longterm plan to
permanently settle Venus.

(atmospheric music)

Though the landscape of Venus

is a hot, high-pressure death trap,

the upper atmosphere
could offer safe harbor.

- In the clouds of Venus,

which is 50 kilometers
up from the surface,

there is a realm where
it's very much Earth-like

in terms of the conditions,

except for the clouds themselves

are made out of
concentrated sulfuric acid.

- Of course, you still have no
atmosphere with oxygen in it.

You still have the sulfur oxides

that give you sulfuric acid.

So you don't want to go
outside without any protection.

But in terms of temperature and pressure,

it's very, very Earth-like.

- So you can imagine sending humans there

and some kind of a balloon platform

or some other floating platform

to explore the clouds of Venus,

and you wouldn't need a pressure suit,

and you wouldn't have to worry

about the thermal environment;
it would be quite pleasant.

You would just need some thin protection

from the acid clouds,

and you would need a breathing apparatus,

since it's mostly carbon dioxide.

But in terms of the environment,

say compared to the surface of Mars,

the clouds of Venus would
be a much easier place

to send human beings.

- [Narrator] Let's take a slice
of the planet's atmosphere.

From the sweltering ground
to the vacuum of space,

200 kilometers tall.

On the surface, you'd feel as squeezed

as diving, nearly a kilometer underwater

and being big twice as
hot as in a pizza oven,

But, rise up 50 kilometers,

and you'll enjoy Earth-normal pressure

and springtime temperatures.

This moderate zone,
high in the atmosphere,

has plenty of light, but
not too much radiation.

It's an ideal location
for a research station.

(intriguing electronic music)

Imagine frequent flights into
the stormy clouds of Venus.

(thunder rumbling)

The airships would be
spun from carbon fiber

harvested from the atmosphere itself,

their electric motors powered by the sun.

Ahead, a permanent floating
station, a cloud city awaits.

- I have been thinking of this idea

that you could float habitats
in the atmosphere of Venus.

And the habit has could be very large,

they could be kilometers in scale.

And the interesting thing
is, if you did this,

you wouldn't even need to
have hydrogen or helium

to make them float, because
the atmosphere of Venus

is mostly carbon dioxide.

Oxygen and nitrogen,
ordinary, breathable air

would float in the atmosphere of Venus.

And inside their giant bubbles,

you can walk around on the inside,

because the air that's holding you up

is also the air that you can breathe.

The lifting gas is your environment.

- [Narrator] The interior
ecosystem can be lush

with plenty of room to breathe

and plenty of acreage for growing food.

This home in the clouds can
be nearly self-sustaining.

Looking up through the
transparent domed rooftop,

you watch vessels come and go.

Suspended beneath the
habitat, the logistics hub

to house its core services
and computer systems.

The docking ports are
staggered across two levels

to accommodate the wide girths
of several airships at once.

(propellor buffeting)

(soft orchestral music)

Expeditions set of off,
launching instruments as they go.

They'll diverge onto different courses,

running survey transects
above the surface of Venus.

- There are some experiments
that you could only do

if you actually go and float
around in the atmosphere.

And what you could do is
answer a lot of the mysteries

that remain about the
atmosphere and the clouds.

There's a lot we don't
know about what the clouds

are made out of, what kind of
chemistry is going on there.

There are gases we call the rare gases:

neon, argon, krypton, xenon.

Or the noble gases, and
they're called the noble gases

because they don't react with other gases.

On the periodic table, they're the column

all the way on the right,

and they don't react with anything.

And because of that, they tend to record

longterm aspects of a planet's history,

because they haven't been
perturbed by chemistry.

And in addition, there are
mysteries of the radiation,

the way solar energy is
absorbed and deposited

in the clouds and in the atmosphere

that we would really like to understand,

both to understand Venus,

and also just to round
out our understanding

of the way climate works on planets,

which of course is very
important to us here on Earth,

struggling with climate change.

There are measurements we would love to do

within the atmosphere of Venus

that could tell us more about the origins

and evolution of that planet.

- [Narrator] The tough balloons
will last for many months,

their sensors alert for
low-frequency, infrasonic waves.

- Is Venus volcanically active?

Does Venus have plate recycling today?

Those are geophysics questions

that could be answered through seismology,

which we can do from balloon,
potentially, by measuring.

This is wonderful, taking
advantage of the fact

that the Venus' atmosphere is so thick

that sound waves from earthquakes

will propagate up through the atmosphere

and can be measured from
balloon or from orbit.

It's astounding.

- [Narrator] Each science buoy
makes a trip around the globe

in about four Earth days.

As they spread out, they
form a global network,

performing standoff
seismology, meteorology,

atmospheric chemistry,
and surface observations.

But if these balloon probes
can collect all these data,

why send people all the way to Venus?

- Humans can do things
that robots can never do.

That's just a fact.

We can think on the fly, we have hands.

The difficulty of putting
hands on another planet,

it's extraordinary.

And link them to a mind.

So, we could ...

with humans in the Venus
clouds or in orbit at Venus,

make observations, it would
be a telescopic observations,

measurements of chemistry,

or set up an observatory at
Venus to study the Venus clouds

and changes that we
might expect to be coming

from volcanic and seismic
activity at Venus.

So it's the Lando Calrissian
model, right? (laughing)

The cloud society at Venus.

We would get more data
by having people there.

- Human beings are marvelously versatile,

but human explorers are a
lot harder to keep alive

in the atmosphere of Venus.

They need oxygen, they
need food, they need sleep.

So I'd love to see human explorers

go to the atmosphere of Venus.

I'd love to see human explorers

that could operate via tele-robotics

some of our high-temperature systems

on the surface of Venus,

so that the humans would
be in the atmosphere,

but they're controlling by virtual reality

a system that's on the surface of Venus.

I thought it would be a
pretty advanced mission.

That's not something that we're
quite ready to do quite yet.

(driving electronic music)

- [Narrator] Success of such missions

will depend on the people who fly them.

No matter how comfortable the
cloud community dwellings,

scientists and engineers
may only agree to work there

if there is a guarantee
of return to Earth.

(rocket roaring)

(curious electronic music)

Habitats in the clouds require energy.

One way to get it is to troll for power:

extend a strong cable from the
cold altitude of the dwelling

down into the hot depths
of the atmosphere.

But don't let it touch the ground.

The difference in temperature
between the cable's top

and bottom can generate electricity,

employing what's known
as the Seebeck Effect.

It's an electro thermodynamic device

that needs no moving parts.

(soft orchestral music)

But there may be an even simpler solution,

one that puts no drag
on the floating station.

- As you get higher and higher,

as you get above the
thickest of the cloud decks

at about 50 kilometers above the surface,

once you get above the cloud
decks, it gets very sunny.

It's actually sunnier than the Earth.

It's not ferociously hot,
because there's still some amount

of the high cloud that diffuses
the light a little bit,

but there's plenty of solar energy.

So I picture the habitats that could float

in the area above the
thick clouds of Venus,

probably as being solar powered.

There's plenty of sunlight,
the temperature is nice.

Why not pop out your solar
panels and run on the sun?

It should work.

(bright orchestral music)

- [Narrator] Solar power on
Earth depends on batteries

to store the energy after sunset.

But nighttime on Venus is much longer.

- The surface of Venus rotates
very slow and backwards,

so if you were on the surface,

the day-night cycle would
be hundreds of days.

But once you get above the surface,

what happens is the clouds

whip around the planet very quickly.

So there's a phenomenon called
atmospheric superrotation.

That means that the
atmosphere actually rotates

faster than the planet.

So at the Earth-like level,
at about 50 to 60 kilometers,

it takes about four days for
the winds to circle the planet.

So if you were floating in
a balloon or in a habitat

that was just stationary
and following the winds,

you'd see about two
Earth days of sunlight,

and then you'd have about
two Earth days of nighttime.

So when you're talking
about power for the habitat,

of course, you would
have to provide for power

for the nighttime, and your nighttime's

going to be about two Earth
days, but that's not impossible.

You could imagine being
solar-powered during the day

and then having enough energy storage

to keep on living and working

and doing whatever you're doing

for your human habitats
during the nighttime.

(soft music)

- [Narrator] Like the
International Space Station,

a modest-sized floating field station

could support a small group of researchers

for deployments lasting several months.

But, using the same materials
and construction techniques,

there's practically no limit

to how big these
structures could be built.

(impressive brass music)

Many could cluster together
to support a relatively large

group of astronauts over
much longer periods.

- I picture the idea of these habitats

as being the size of
cities, kilometers in scale.

So I sort of love the idea, and of course,

once you put in one city
in the atmosphere of Venus,

why not more, why not 10, why
not a 100, why not 10,000?

There's a lot of Venus out there.

- [Narrator] But how safe
are these structures?

- Well, the nice thing about the balloons

in the atmosphere of Venus,
if they're very, very large,

is that they'd be running
with the inside pressure

about the same as the outside pressure.

So it wouldn't be like a space habitat,

say an O'Neill habitat in Earth orbit,

where if you puncture a hole in it,

you get an explosive decompression

and all of the air rushes out.

You'd have the outside air

is about the same pressure
as the inside air.

There'd be some exchange of gases.

You wouldn't want that, but it
wouldn't burst like a balloon

in a catastrophic failure.

When you have something this big,

it takes a very, very
long time to decompress.

If you pop a balloon that's this big,

it's over in an instant,

but when you put a hole in a balloon

that's hundreds of meters across,

it takes a long time to deflate.

And something that's
thousands of meters across,

a city, would take days and days

to lose very much atmosphere.

Nevertheless, of course,

I think you'd want to work very hard

to make sure that you
don't get those punctures

and you'd make sure that you have multiple

lifting gas areas, so
that even if you did,

for one reason or another, have a failure

that made one part of
the city lose atmosphere,

the rest of it would have enough
lifting gas to hold you up.

- [Narrator] These are
large, complex assemblies.

Fortunately, very little of their mass

would have to be hauled here from Earth.

- A lot of the materials

that you could use to build a habitat,

you might be able to make just
from the atmosphere of Venus.

It turns out that, in modern engineering,

one of the most versatile,
one of the most useful,

materials you can make is carbon fiber.

Carbon fiber is strong. It's lightweight.

You can do a lot with carbon fiber.

But of course, to make a
whole city, you need more

than just the structural
members of carbon fiber.

So I expect that, if
we were making a city,

or 10 cities, or 1,000 cities,

we're probably going to have
to go down to the surface

and grab up materials.

So, you will be mining
the surface of Venus

to bring up other materials

like the silicon and the silicate rocks

and the lesser materials.

There's a lot you can get
out of the atmosphere,

but not everything of course.

What you want to avoid
doing as much as possible

is you want to try to avoid

bringing things all the way from Earth,

because the key to living
in the solar system

is learning to use the materials
that you can find on-hand.

Bringing things up from
Earth as a camping trip,

but we don't want to just go camping.

We want to live in the solar system.

(light orchestral music)

- [Narrator] What began with a few

science outposts and airships

could expand into a far
flung, interconnected network

of communities beyond Earth.

(gentle percussive music)

The old romantic vision of
self-sustaining space settlements

could come alive in the orbit of Venus.

Habitats many kilometers in size

can be constructed from materials

mined from the atmosphere or asteroids,

and they'd be powered by free
energy from the nearby sun.

These utopian structures could rotate

to provide comfortable
gravity and pleasant weather.

Large ships could dock there,

bringing cargo to be distributed
down the gravity well

to the floating towns
in Venus's atmosphere.

But the builders of such a
city will have to wrestle

with one inevitable design constraint:

most of the mass must be allocated

to sheltering the
residents from radiation.

- If we had a colony at the
launch points, for example,

we'd probably have to shield them

with many meters of regolith, of dirt.

Well, that's okay. We can
mind dirt from the moon.

The moon's got plenty of dirt.

But that's a lot of
stuff you have to bring

for no other purpose than hiding away

from the particles
coming away from the sun,

galactic cosmic rays
coming in from outer space.

- [Narrator] On the other
hand, the cloud dwellers

would be safely tucked
into the atmosphere.

- Venus does not have a magnetic
field to deflect particles,

but it still does have an atmosphere.

So at the level of the
middle cloud deck of Venus

and a little bit above,

we're still talking
about a lot of atmosphere

between you and space.

So the good thing is that
we have enough atmosphere

to attenuate the worst of the radiation.

We're not getting the protons

from the solar flare
coronal mass ejections

that would be very, very dangerous,

maybe very deadly for
an unprotected human.

We get the 10 tons of
atmosphere per square meter

shielding us from the radiation.

Another reason that the clouds of Venus

are a nice place to colonize.

(atmospheric music)

- [Narrator] Venus has nearly
the same gravity as Earth.

While it has much more land
area, it has no oceans.

What would it take to make
the entire planet livable,

to terraform it?

We would have to re-water the whole world.

(atmospheric electronic music)

In the early solar system,
the second planet, Venus,

may have been the most hospitable of all,

but as the sun brightened,

Venus struggled to hold on to its oceans.

Carbon dioxide and methane
from volcanoes trapped heat,

evaporating the seas.

(steam hissing)

(uncanny music)

Atmospheric water vapor
became a greenhouse gas,

holding even more energy from
the sun and the planet below.

- Four and a half billion years ago,

Earth's atmosphere was also CO2-rich.

That is, the original atmosphere
of the terrestrial planets.

Venus has a very thick carbon
dioxide atmosphere today.

And we would, too, if you took
all of the carbonate rocks,

the rocks that hold carbon,
took all the limestone on Earth,

took Florida, evaporated
it back into the sky.

All that carbon dioxide

would be about the equivalent
of the carbon dioxide

that's in the Venus atmosphere right now.

- Venus is really off
the scale in a sense.

For us to load our atmosphere

with the amount of CO2
that's in Venus's atmosphere

would require us to free
up all the carbonate rocks

on our world and get all that carbon

into the atmosphere.

And that would take hundreds and hundreds

of millions of years.

- [Narrator] Space visionaries today

are looking to advanced technologies

to send Venus back in a
more Earth-like direction.

- You would have to,
obviously, do something

about the very, very
strong greenhouse effect.

Maybe you would do that
by putting aerosols

into the atmosphere,

filling the atmosphere with dust

long enough to collapse that greenhouse

and get that CO2 to
condense out on the surface.

And then you'd have to find
some way to keep it condensed,

maybe with, now we're getting
science fictional here,

but maybe with orbiting
mirrors or something

to cut down on that solar radiation.

- [Narrator] British scientist Paul Birch

proposed transporting
trillions of tons of hydrogen

from gas planets such as Jupiter.

The idea is to convert atmospheric
CO2 into oceans of water,

plus mountains of graphite.

Birch also suggested shielding
Venus from the sun's heat

with enormous, thin panels ...

to cool the atmosphere,
shrink its volume ...

and lower its pressure.

(uncanny music)

These giant screens would
convert solar energy

to power other terraforming operations ...

like capturing carbon and
sealing it underground.

Nobel Prize winner Paul Crutzen

proposed injecting sulfur
dioxide into the air

to simulate the dark smoke
of gargantuan volcanoes

to cool the surface and
tame the greenhouse.

David Grinspoon and Mark Bullock

suggest that exposing
native calcium and magnesium

could pull carbon down
into carbonate rocks.

(uncanny music)

But where to find a whole
planet's worth of water?

- Fortunately, I suppose,
if this was your goal,

there's a lot of stray icy
objects in the solar system,

the whole outer solar
system, the Kuiper Belt,

is loaded with icy objects and
would not miss a few of them.

There are literally trillions
of icy objects out there.

So if you're imagining some far future

where somebody's got the technical prowess

and the will to do this,

I would take some of
these large, icy objects,

some large number of them
and crash them into Venus,

which would both raise the
dust to collapse the greenhouse

and would return Venus to
a more watery condition.

This is not a near-term
project. (chuckles)

(frenetic string music)

- [Narrator] To put icy
objects on a collision course

with Venus takes delicate
orbital mechanics,

a slow-motion ballet of many small robots

with the collective power
to move mega mountains.

The swarm distributes itself

according to the unique gravity
map of the chosen object.

Choreographed clusters of thruster firings

nudge each massive ice world inbound

onto its own safe trajectory.

The bots may process
their captured objects,

separating out water and extracting metals

during their long journey
to the inner solar system.

The icy bodies may change
shape as materials are mined.

These intelligent machines

might also make clones of themselves

to scale up the operation
and get it done faster.

(booming)

When the processed icy asteroids arrive,

they'll be delicately
maneuvered into impact speeds

that preserve the most water.

(rumbling)

Dust from the crashes
should cut down sunlight,

cooling it quicker.

But smack the planet too hard,
and you may unleash hell.

Count on Venus to fight back.

With a thicker crust
and no plate tectonics,

Venus doesn't vent its internal
heat as easily as Earth.

It builds up.

This world has erupted and
repaved its entire surface

at least once in its history

(tense music)

(gentle music)

To remodel an entire planet

seems like the ultimate act of hubris,

but we're already doing it.

- Could we ever terraform
Venus and go live on it?

Well, our more immediate task

is to avoid veneraforming Earth right now.

That is, to not turn Earth into Venus

by increasing the greenhouse effect.

So I don't advocate immediately going

and trying to live on Venus or Mars

and trying to terraform them

to escape from our problems here.

However, the mental exercise of imagining

how we would terraform another planet,

I think, is very valuable for our task

of learning how to manage
ourselves on Earth better,

because it forces us to ask,

how would we interact
constructively with the planet?

How would we intentionally
alter a planet's climate

and manage a planet's climate

as opposed to unintentionally
and inadvertently

messing with a planet's climate

as we've been doing here on Earth?

- I think actually learning
to live in the solar system

is going to teach us ways
to help us live on Earth.

What we call pollution on the Earth,

on the moon we'd call
that valuable resources.

That's gonna help us live on Earth,

just understanding that an
ecosystem is a closed cycle.

There is no such thing as waste.

All of the waste has to
be recycled and come back.

- [Narrator] On the other hand,

learning the techniques
to better manage Earth

might just give us the tools

to tackle living on or
around other worlds.

It might take decades,
centuries, millennia ...

but our distant descendants
may well be born

into a solar system with more
than one place to call home.

Some may be in the clouds of atmospheres.

(soft piano music)

Some may orbit freely.

Still others might live
on the surfaces of worlds.

- I think we should move
out into the solar system,

and I really want to go everywhere.

I want to put human beings
at the poles of Mercury.

I want to go to Venus.
I want to go to Mars.

I think we should go into
the outer solar system

and start looking at some of the resources

of the Kuiper belt.

I think human beings can, and we should,

settle the whole solar system,

- [Narrator] As it was when
the planets first formed,

Earth's twin made
beckoned us to its shores.

(building orchestral music)

(intriguing instrumental music)