All language subtitles for NOVA.S52E20.Operation.Space.Station.Science.and.Survival.1080p.WEB.h264-BAE_track3_[eng]

♪ ♪

NARRATOR:
Earth.

Over eight billion people
live here.

But not all of them are home.

Since the turn of the century,

a few have been living here...

♪ ♪

...in the most hazardous
scientific outpost ever built:

the International Space Station.

♪ ♪

Altogether, over 280 people

have ridden
a controlled explosion

250 miles into space,

risking their lives

to maintain a continuous
human presence off planet.

One day, we may be getting ready
for a spacewalk

and the next day, we'll be doing
some world-class science.

♪ ♪

NARRATOR:
Its unique environment
provides a research laboratory

like no other.

But conducting science in space

brings its own challenges.

RAJA CHARI:
Very quickly, you can have
an out-of-control situation

from a very innocuous start.

♪ ♪

NARRATOR:
As astronauts push

the boundaries
of science and exploration,

they face daily threats.

(over radio):
CO2 sensor bad.

MAN:
Copy, Luca.

LUCA PARMITANO:
You are constantly at risk
of dying

for a multitude of reasons.

♪ ♪

WENDY LAWRENCE:
You've got orbital debris

that can hit your module

and put a hole in it.

♪ ♪

CHRIS CASSIDY:
In the military,

we say that problems happen

at the fold of a map
and at night.

And that's exactly
how this was shaping up.

ZEBULON SCOVILLE:
How do we respond

to that unknown?

Understanding situations

may have
the ultimate consequences.

(alarm beeping)
MAN (over radio):
Station, Houston on 2.

This is an actual.

NARRATOR:
This is the story of innovation

and scientific exploration

aboard the I.S.S.

"Operation Space Station:

Science and Survival."

Right now, on "NOVA."

♪ ♪

NARRATOR:
June 2024.

The world is gripped by a drama
playing out far above Earth.

NASA astronauts Butch Wilmore
and Suni Williams

had been scheduled
to spend just eight days

aboard the
International Space Station

while testing
a new commercial spacecraft,

the Boeing Starliner.

WILLIAMS (over radio):
Into the spacecraft!

NARRATOR:
Instead, when the vehicle
encounters technical issues,

their mission stretches
into months.

Despite the difficulties,

the pair pivots to become
routine crew members,

drawing from their years
of training

and a deep love of the job

to embrace
their extended mission.

Because this job
is like no other.

We're still pioneers in space,

so there's still a lot
that we have to learn.

(over radio):
Okay, my yellow hook,

closed and locked.

NARRATOR:
Space is incredibly risky.

The safest thing to do is to not
go anywhere,

about your species
or the planet you live on.

You have to take risk
to get the reward.

NARRATOR:
Butch and Suni's extended stay

is just the latest
in a long line

of unexpected challenges
faced in orbit.

MAN (over radio): And lift off.

The International Space Station

is underway.

NARRATOR:
Since the space station's
first module

was launched in 1998,

there have been countless
moments of risk and uncertainty.

ROBERT CURBEAM (over radio):
There's ammonia all over the
place.

NARRATOR:
Requiring calm
and quick thinking to resolve.

TOM JONES (over radio):
You just pulled the bail?

CURBEAM: Yeah.

And that stopped the leak.

NARRATOR:
All to create
a unique research laboratory,

a platform for international
science and discovery

through cooperation,

uniting humanity
in the pursuit of knowledge

beyond our planet.

♪ ♪

From monitoring hurricanes
on Earth

to cultivating plants in space.

From detecting X-rays
released by neutron stars

to developing
cancer therapeutics.

RENITA FINCKE:
We have taken technologies,

people, systems
from all over the world,

and we've put it together
into this amazing laboratory.

♪ ♪

The research
that we've been able to do

has directly benefited
life on planet Earth,

and we're only
just getting started.

♪ ♪

NARRATOR: Every minute of an
astronaut's day on the station

is carefully planned,

and life on board
might even come to feel routine.

But it's always
just a matter of time

before the universe finds a way
to remind the crew

of just how vulnerable they are.

♪ ♪

In 2013, plans are underway
to further extend

the International Space
Station's scientific footprint.

A new module called Nauka,

Russian for "science,"

is to be added to the station
the following year.

Created to conduct

materials science
and biotechnology research,

Nauka includes a base
for the European Robotic Arm

and will also feature
a specially designed airlock

to carry out experiments
in the vacuum of space.

♪ ♪

But to unlock
this groundbreaking science,

astronauts must brave
the most unforgiving extremes.

CASSIDY:
In my personal operational
experience in the military,

in the SEAL teams,

the bad guys were the enemy
that's shooting at you.

In a space mission,
the "bad guy"

is the environment.

♪ ♪

The environment
is trying to kill you.

PARMITANO:
Space is not really
made for life.

It's very cold and very hot
at the same time.

It doesn't have an atmosphere.

It really doesn't want
to keep you alive.

NARRATOR:
A spacewalk,

also known as an extra-vehicular
activity, or E.V.A.,

is especially dangerous.

Astronauts usually go
through the airlock in pairs

so that once outside,

they can assist each other
if needed.

But still, they are isolated

and vulnerable to hazards
like radiation,

micrometeoroid impacts,

and equipment malfunctions.

On July 16, 2013,

American astronaut Chris Cassidy

and flight engineer
Luca Parmitano

don their spacesuits.

Spacewalks are not
something that you just

willy-nilly do--
"Hey, it's Tuesday.

You want to go out
and knock out a spacewalk?"

No, it doesn't work like that.

Takes about four hours

to go through the oxygen
pre-breathe process

and all of the checks leading up

to opening the hatch.

(over radio):
All right, I have
a waist tether,

gate closed and locked.

(voiceover):
All spacewalkers

are tethered
to the space station

with a retractable metal cable

that pays out to 85 feet.

And just like if you walk
a pair of dogs on dog leashes,

those leashes
get all tangled up.

PARMITANO (over radio):
On my way.

CASSIDY (voiceover):
Safety tethers are no different.

So, oftentimes,

we intentionally
take separate routes,

so the safety tethers

don't tangle up on themselves.

NARRATOR:
Luca and Chris come together

on top of the Tranquility module

to carry out their task:

connecting data
and ethernet cables

for when the new module arrives.

38 minutes into the E.V.A.,

a warning alarm is triggered
in Luca Parmitano's spacesuit.

The carbon dioxide levels
are too high.

PARMITANO (over radio):
CO2 sensor bad.

MAN: Copy, Luca.

It measures 48.6.

CASSIDY: Copy that, Luca.

(exhales)

NARRATOR:
Ordinarily,
exhaled carbon dioxide

would be controlled and removed

by the Portable
Life Support System

in Luca's backpack.

The alarm could signal

a dangerous buildup of the gas

inside his spacesuit,

which could lead
to severe headaches,

impaired judgment,

and even death.

PARMITANO (voiceover):
We have a checklist

telling us to check
different parts of the suit

to understand whether it is
an actual alarm

or whether the sensor itself
is at fault.

CASSIDY:
It said, "Did the reading
go from normal

to ludicrous instantly?"

If that happened, then
it's probably the sensor's bad.

MAN (over radio)
And Luca, nice work
on the cuff checklist,

but no further action
on your part.

NARRATOR:
Doubtful of the carbon
dioxide reading

and satisfied
that Luca has no symptoms,

Mission Control concludes
that the sensor is faulty,

and the E.V.A.
can continue as planned.

(static hisses)

But six minutes later,

Luca calls Mission Control
again:

there's another issue.

PARMITANO (over radio):
F.Y.I.,

I feel a lot of water
on the back of my head.

MAN:
Are you sweating?
Are you working hard?

PARMITANO:
Um,

I am sweating,

but feels like a lot of water.

MAN:
Yeah, Luca, we copy.
MAN: Copy.

PARMITANO:
Just F.Y.I.

(voiceover):
There should never be

any water inside your
space suit,

especially not in the, in the
helmet area,

(chuckling):
And I said, "I don't think
it's a big deal."

I just wanted to keep
going with the E.V.A.

MAN (over radio):
Hey, Luca, while you're
working there,

can you give us, uh,

maybe some more words
on the water?

Um, maybe identify
the source, do you think,

and then,
is it getting any worse

or is it the same?

PARMITANO: Um, good questions.

It's still the same,

and I cannot tell you
the source.

NARRATOR:
On Earth,

water falls
under the force of gravity.

In space,
it's much less predictable.

CASSIDY:
It's surface tension

that drives
the behavior of water.

That surface tension
is a pretty strong force,

and the water
just wants to stick

to whatever it's stuck to.

NARRATOR:
In Luca's case,

the unexplained ball of water

is sticking
to the back of his head

and threatening to creep around
toward his face.

PARMITANO:
My biggest concern

was the water
getting inside my ears.

(static hisses)

Because if it did,
it's really hard to get it out.

You cannot tap your head--
there's nothing you can do.

(static hisses)

CASSIDY:
I finished what I was doing

and got over close to him,
and I remember,

I could see, it looked like

half of a grapefruit
just kind of jiggling

on his head.

(Parmitano panting softly)

CASSIDY:
And then little bitty pieces

(on radio):
I see beads of sweat.

PARMITANO: No, it's not sweat.

CASSIDY: Oh, it's not sweat.

MAN:
Hey, Luca, can you clarify,

is it increasing
or not increasing?

PARMITANO: It's hard to tell,

but it feels
like a lot of water.

CASSIDY: Oh, I see, yes.

I see it now, wiggling.

PARMITANO:
And, um, I, I can't,
don't understand

where it's coming from--
it can't be the water...

CASSIDY: It has to be the bag.

NARRATOR:
At the European Space Agency,

astronaut instructor
Hervé Stevenin

watches a live feed
of the mission.

(Stevenin speaking French)

(translated):
They thought it might be

the small water bag
that the astronauts carry.

There is a small bag

which is attached to the stomach
with Velcro

and contains around one to
one-and-a-half liters of water.

This has a little straw,

to enable the astronaut
to stay hydrated.

CASSIDY (over radio):
And you've sucked it dry?

PARMITANO:
Okay, the bag is dry now.

NARRATOR:
But the situation
doesn't improve.

CASSIDY:
The bag is empty now.

And, uh,
you know, there's something

less than a liter
in the back of his head.

800 milliliters, maybe.

MAN:
All right, Chris.

NARRATOR:
More water collects
in Luca's helmet.

PARMITANO:
Yeah, I'm thinking that it might
not be the water bag.

The only other option, Chris,
that I'm thinking

is the LCVG.

NARRATOR:
The LCVG,

or Liquid Cooling
and Ventilation Garment,

circulates cold water
in the spacesuit

via a system of tubes

to prevent astronauts
from overheating.

As Chris and Luca correctly
suspect,

Luca's LCVG has malfunctioned

and is leaking water
into his helmet.

The very suit
designed to protect him

from the dangers of space

may now be putting him
in mortal danger.

CASSIDY:
That's the moment, I think,

where it solidified
in everybody's mind,

"Okay, we're done for today."

NARRATOR:
67 minutes into the E.V.A.,

Mission Control
terminates the spacewalk.

MAN (over radio):
All right, Chris and Luca,
just for you guys,

we think we're are gonna
terminate E.V.A. case for EV2.

So, Luca, we'll have you
head back to the airlock.

Chris, we'll get a plan for you

to clean things up here

and then join him in a minute.

NARRATOR:
Luca needs to get back
inside the space station

and remove his helmet.

He begins retracing his route

back to the airlock,

while Chris clears away
their tools.

PARMITANO:
I remember leaving Chris,

and as I made the corner
and disappear from sight,

I remember thinking

that I really wish that Chris
could come with me,

because that's how we train.

We train to be together--
that's why we go outside

as a team, so that
we have each other's back.

CASSIDY:
Before I saw Luca disappearing

behind the Z1 truss...

And I wanted to say out loud,

"Luca, stop, hold on,
I'm coming with you."

It just felt like
that's what we should do.

NARRATOR:
But as tempting as it is
to hurry,

Chris follows orders

and forces himself
to move deliberately.

In the military,
we say that problems happen

at the fold of a map,

at the junction of grid squares,

and at night.

And that's exactly
how this was shaping up.

As soon as he started to move,

the sun set.

PARMITANO:
And everything turns gold,
bright gold,

for one split second.

Incredibly beautiful,

and then it's lights out.

(static hisses)

(static hisses,
water drips on radio)

NARRATOR:
The I.S.S. takes
around 90 minutes

to orbit the Earth.

For half this time,

the space station
is in total darkness.

(static hisses,
water drips on radio)

CASSIDY:
Now, once Luca started to move,

well, what happened
to his motion,

it gets transferred
into the water, too,

so that stationary jiggly ball
of Jell-O

starts flushing around his head.

♪ ♪

PARMITANO:
I felt it coming closer
and closer to my forehead

and I thought,
"Okay, this might cover

"both of my ears
at the same time.

"It may be more
than a simple hindrance.

It may be an actual,
an actual problem."

And I just completed a maneuver

where I put myself upside down,

so all my terms of reference

had completely switched
180 degrees.

That's when the water really
completely covered my nose...

...and I found myself isolated,

unable to see anything,

unable to breathe
through my nose.

I didn't really know
how much time I had

before the water
reached my mouth.

NARRATOR:
If too much water covers
both Luca's nose and mouth,

he'll be unable to breathe

or drink his way out of trouble.

(radio static hissing)

And to make matters worse,

water enters Luca's comms,

causing it to malfunction.

PARMITANO (over radio):
Hey, Chris?

CASSIDY:
I hear you, Luca, go ahead.

(radio static hissing)

Luca, I hear you.
PARMITANO:
Chris?

Yeah...

(radio static hissing)

(translated):
There are two mics here,
and when Luca talked,

all we could hear
were gurgling sounds.

This was terrifying to hear
for us here in the control room.

At this stage, we realized

that something serious
had happened,

very bad and very dangerous.

(water bubbling)

My memories are of just

trying to feel around,

making sure that I would grab
the correct handles

in a pressurized glove,

which gives you no feedback,
no tactile feedback.

And I called Chris, telling him,

"Hey, Chris,
I, I think I'm a bit lost,"

but nothing came out,

and I, I didn't have any return
in my earphones,

so I knew
that he couldn't hear me.

(water bubbling)

And at the time,
my thoughts were,

"Okay, I don't think
Chris is going

"to come and get me right away.

How much time do I have?"

That was my thought in my head.

"How much time do I have

before this helmet
fills up with water?"

There was a risk

that if the water increased
dramatically,

I would drown in space.

NARRATOR:
For the next five minutes,

Luca will be completely
silent and alone.

♪ ♪

(water drips)

CASSIDY:
He had the amazing presence
about himself,

when everything
kind of went dark and silent,

to just stop.

(water bubbling)

NARRATOR:
At that point, Luca remembers

he is tethered to
the space station's airlock.

STEVENIN (translated):
His cable extends

all the way along the route,
creating a safety line.

If the astronaut were
to float off into space,

this cable would slowly pull
them back towards the airlock.

(speaking French)

CASSIDY:
That tether has a little
three- or five-pound pull to it,

and he waited to feel
the direction of that pull.

And then he just put his hand
over

and grabbed the next piece
of metal that he could find,

and inched his way back
that way.

Unbelievable awareness by Luca.

♪ ♪

NARRATOR:
The gentle tug
of the waist tether

leads Luca back to the airlock.

But he's not safe yet.

Before he can
take his helmet off,

the airlock must be sealed
and repressurized.

With no time to waste,

the I.S.S. crew runs
through their checklist.

Five minutes later,

Chris joins Luca,
squeezing in feet first.

CASSIDY:
The only thing that mattered
at that point

was the hatch being closed.

Because if we couldn't
close the hatch,

we couldn't get
good air pressure.

If we couldn't get air pressure,

we couldn't get Luca's helmet
off,

and we can't get
Luca's helmet off,

pretty soon,
he's not going to have

air in his helmet to breathe.

NARRATOR:
With Luca's comms
malfunctioning

and water now obscuring
his vision,

Chris must ready the airlock

before crewmate Karen Nyberg
can repressurize it.

(man speaking faintly
on radio)

As they speed through

the normally 15-minute-long
airlock procedure,

Ground Control attempts
to check in with Luca.

MAN (over radio):
Hey, Luca, from Houston.

How you doing? Give us a status.

(water bubbling)

NARRATOR:
But there is still no response.

CASSIDY:
Luca, do you hear that?

(water bubbling)

NARRATOR: The pair
are positioned head-to-foot,

making it difficult for Chris
to see into Luca's helmet.

(static hissing)

CASSIDY (over radio): Shane,
I don't think he can, uh...

His voice is going out or you,

he can't hear you, but...

I'm trying to see him.

Right about then,
I grabbed his hand.

(over radio): Squeeze my hand
if you're fine, Luca.

(static hisses)

Luca, squeeze my hand.

Everything okay?

You okay?

And we had never
pre-briefed this,

never talked about it,

but I squeezed his hand.

(static hisses)

(over radio):
Roger that.

Shane, visually confirmed,

he's doing okay.

♪ ♪

Sorry to my wife, but,

there'd been never
a more comforting

squeeze back of a hand.

♪ ♪

That sensation of feeling
his hand squeeze back

in a nice, controlled way

was, like, "Okay,
we're going to be all right."

(over radio):
He looks fine.

He looks miserable, but,

uh, okay.

MAN:
Copy all, Chris, uh,

we'll just status you
from now on to check on him.

(Cassidy's mic crackling)

CASSIDY: 14 PSI, Karen.

NYBERG: Hatch coming open.

(static hissing)

MAN:
Airlock, Houston.

Uh, if you could have
some towels ready,

that would be great.

NYBERG: We have them here.

PARMITANO (voiceover):
As my crewmates from the inside

were opening the hatch,
I looked up,

and I could see Karen,
Karen Nyberg's face,

and Fyodor.

The whole crew had come into
the airlock to help me,

and their faces,

they were so worried.

CASSIDY (over radio):
Hatch is open, Shane.

Luca's going
through the airlock.

MAN:
Copy, Chris, thanks.

The sense of friendship,
camaraderie,

it's a form of love that,

that we should explore more,
I think.

♪ ♪

I could feel it,
I could sense it,

I could see it on their faces,
and I was moved.

MAN (over radio):
Okay, Chris, just hang tight
for a bit.

Once we get Luca taken care of,
we'll work on you.

CASSIDY:
No problem, I'm in no rush.

I got a ringside seat.

PARMITANO (voiceover):
I was obviously relieved.

I knew that the ordeal

was just about to end

when they took the helmet off.

♪ ♪

I was all smiles,

and I started cracking jokes.

They were certainly happy
to see me.

I was certainly happy
to see them.

♪ ♪

NARRATOR:
A thorough investigation

reveals that a clogged filter

led to the leak in Luca's suit.

To ensure that astronauts
can keep breathing

if such a thing happens again,

NASA has an absorbent pad
and even a makeshift snorkel

installed into each helmet.

♪ ♪

The way water behaves in space

is just one aspect
of microgravity,

which is one-millionth
the gravitational pull

experienced on Earth.

And it's what helps keep
the space station in orbit.

♪ ♪

It's a challenge to live
and work in microgravity,

but it also allows
for groundbreaking studies

to be carried out on the I.S.S.

♪ ♪

Biomedical experiments in space

reveal that in microgravity,

protein crystals form more
uniformly, with fewer defects.

JENNIFER BUCHLI:
They tend to be higher quality.

They tend to be purer
and larger.

And so, this has really been
a great application

for the pharmaceutical industry.

NARRATOR:
A team of Japanese researchers

has taken advantage
of the I.S.S.'s Kibo laboratory

to investigate proteins
associated

with Duchenne's
Muscular Dystrophy...

...a severe genetic disorder

causing progressive
muscle weakness.

BUCHLI:
That series of experiments
were really successful

in finding some of the crystals
associated with those proteins

that they weren't able
to do on the ground,

and develop drugs
to target those.

NARRATOR:
Other experiments focus
on the astronauts themselves

and the impact
the microgravity environment

has on their bodies.

A vital area of research

if humanity is to venture
farther out into space.

And we give periodic samples
of blood

and urine and saliva,
and, in some cases, number two

to test all of the different
outcomes on the body.

PARMITANO:
We are both the conductors
and the test subjects.

We don't like the term
"guinea pigs"

because, uh, because we're not,

but we are subjects of the same,
of the same kind of experiments.

♪ ♪

In the end, we are interesting
in, what can we glean

from performing science
on the human body in space

that we cannot on the ground?

♪ ♪

NARRATOR:
Every part of the space station
is crucial

to conduct this science

and maintain the lives
of its inhabitants.

All the things we might take
for granted here on Earth--

air, water, food--

have to be designed, calculated,
and engineered

to work properly
in microgravity.

Even using the toilet.

CASSIDY:
Close the lid.

CASSIDY (voiceover):
You gotta be able to use
all of your facilities,

whether it's the bathroom

or the air conditioning
or the water processor.

All of those systems
are there for a reason,

because you need them.

Let's take a peek
at the process.

NARRATOR:
With so little gravity,
space toilets use air flow

to pull urine and feces
away from the body

and into the proper receptacles.

And this valve is what activates

(voiceover):
Going number one,

you feel pretty confident
with that.

You're effectively
just turning on a fan,

opening a valve,
and, and peeing.

In good NASA fashion,
we have a checklist.

This is called procedure 2.301,

and in case things go wrong...

Going number two
is a little bit more...

Yeah, you, you really
reread every little line.

There's a plastic liner in
there, where your deposit goes.

If you make the mess,
you got to clean up the mess.

So you don't want to be
that one.

You take this red tab,
you pull it off the rim,

and we do have a, a stick,
and you push it down in there.

And then it's time
to put a new bag on.

Ready to go.

(toilet flushing)

NARRATOR:
But the toilets are vital

to the International Space
Station in more ways than one.

CASSIDY (voiceover):
Water is life.

Water is life on Earth.

Water is life on
the International Space Station.

Every drop of water,

whether it's your urination,

whether it's your sweaty
T-shirt from exercise,

the moisture in our breath
as we exhale,

all of that moisture
gets captured

by the Environmental Control
System

and put back
into the water processor.

NARRATOR:
This fundamental part
of the space station's

Environmental Control
and Life Support System

allows the I.S.S.
to recycle 98% of the water

that a crew brings along
at the start of a mission.

CASSIDY:
Every now and then, as
you're filling your coffee bag,

you think, "Wait a minute,

this was yesterday's coffee,
and it's also today's coffee,"

but the, the system works
really well,

and you get alarms long before

it, it is anything
but pure water.

NARRATOR: While the systems
on board are designed

to keep the crew alive,

it is the responsibility
of the crew

to maintain
the space station itself,

a fundamentally
symbiotic relationship.

Neither could survive
for long periods in space

without the other.

The I.S.S.

is the largest human-made
structure in orbit ever built,

with a surface area
of well over 100,000 square feet

exposed to the hostile
environment of space.

One of the dangers in space
that's outside the vehicle

are what we call
micrometeoroids.

So those can come
from a number of sources.

LAWRENCE:
Bits of cosmic dust

traveling at a tremendously
high speed

can hit the shell of your module
and put a hole in it.

♪ ♪

NARRATOR:
Impact tests conducted
on the ground

reveal the destructive force
of high-velocity particles,

some no larger
than a grain of sand.

Incoming particles
can reach speeds

of up to 162,000 miles per hour,

up to 50 times faster
than a speeding bullet.

The I.S.S. has survived

several direct hits
to its solar panels

and to the Canadarm2.

MICHAEL LÓPEZ-ALEGRÍA:
The smaller pieces
cause problems

because they're going very fast.

So you multiply a very
small number, which is the mass,

times a very big number,
which is the velocity,

that's where
you get the problem.

NARRATOR:
The result is that even
the tiniest particles can pack

a huge punch.

To defend the space station,

more than 100 shields protect
the critical components.

A common kind
is a stuffed Whipple shield...

...a multi-layered system of
metal and synthetic materials,

which can break up
smaller meteoroids,

dispersing their energy.

KWATSI ALIBARUHO:
Russian modules tend to have

thicker ribs and thinner skin.

So from a probabilistic
perspective,

the Russian modules are much
more susceptible

On the flip side,
the U.S. modules have

very, very thick skin.

So smaller micrometeoroids

are not likely
to penetrate the U.S. module.

NARRATOR:
But micrometeoroids
aren't the only threat.

LÓPEZ-ALEGRÍA:
Increasingly,

it's orbital debris that comes
from something human-made.

So a screw, a paint fleck,
a rocket body--

I mean, it could be anything,
right?

LAWRENCE:
There are so many more objects
in space.

There may be bits
of derelict satellites

that approach your orbit.

NARRATOR:
With low Earth orbit becoming
more crowded by the day,

the probability of catastrophic
collision increases.

CHARI:
The good thing
about low Earth orbit is,

we've seen this huge boom

of private companies
and commercialization,

and it's everywhere.

Now, the bad thing is,

there's lots of old pieces
of stuff out there,

whether it's
spent launch vehicles,

whether it's dead satellites.

NARRATOR:
Protecting the I.S.S.
now poses a unique challenge.

Today, more than 15,000 pieces
of space debris

are tracked in low Earth orbit,
where the I.S.S. resides,

including fragments
of used rockets

and decommissioned satellites

that, with no way to regulate
their temperature,

repeatedly expand and contract,

until they break up
or sometimes even explode.

And these are just the objects
we are able to track,

those larger than four inches.

Add in smaller fragments,

and the total number
of debris particles

is estimated to be
in the millions.

Each fragment can go on
to hit more objects,

creating exponentially more
fragments and more collisions.

A potential nightmare
for Mission Control.

The bigger pieces
we track pretty well.

And we do debris avoidance
maneuvers sometimes,

because we know that there
is a potential collision.

NARRATOR:
In 2021, Russia launched
an anti-satellite missile,

deliberately destroying one
of its own defunct satellites.

The impact created a massive
cloud of high-velocity debris

hurtling
through low Earth orbit.

Although the initial pass
missed the station,

the danger was far from over.

Subsequent orbits
of the wreckage

required Mission Control
to carry out avoidance maneuvers

to keep the I.S.S.
out of harm's way.

Every maneuver, every docking,

is painstakingly planned
and monitored

by the folks at Mission Control.

And during these tightly
coordinated movements

of the space station,

controllers must be ready
for the unexpected.

TRANSLATOR (over radio):
The range is three meters.

(man speaking Russian)

TRANSLATOR:
Range...

(man speaking Russian)

TRANSLATOR:
...is 0.1.

We're standing by for contact.

NARRATOR: July 29, 2021.

After years of delays,

the uncrewed multi-purpose
laboratory module,

or MLM, Nauka

docks with
the International Space Station.

It marks the first major
expansion to the Russian segment

in over ten years.

Once docking to the Zvezda
Service Module is complete,

at Mission Control in Houston,

Zebulon Scoville takes
over flight director duties.

SCOVILLE:
I did a quick handover
and plugged in,

thinking that we were
just going to be

doing some minor
reconfigurations

and stabilizations of
opening hatches,

equalizing the atmospheres,
and so forth.

It didn't quite go that way.

About one-and-a-half minutes
after plugging in my headset,

a small yellow stripe lit up
across the caution warning board

in the front of Mission Control.

My attitude control officer

notifies me that we have
a loss of attitude control,

or LOAC.

NARRATOR:
For reasons unknown,

the I.S.S. has begun
to spin out of control.

SCOVILLE:
We saw on the front screens,

the video cameras coming
from I.S.S.,

almost a snowstorm of particles

around the outside of the I.S.S.

And it wasn't entirely clear
what the source of this was.

This could be

a coolant fluid that had vented,

it could be a fuel or propellant
that was leaking overboard,

or it could be thrusters firing.

The fact of the matter is,
we didn't know.

And so this is where we had to
very quickly try to understand,

what is this venting overboard?

What is it doing to I.S.S.?

How will we, first, make sure
this crew is going to be safe

and, second,
get the vehicle under control?

MAN (over radio):
Station, Houston on 2.

We need you in
two decimal seven zero two.

This is an actual.

NARRATOR:
French astronaut Thomas Pesquet
and his six crewmates

are onboard at the time.

(speaking French)

(translated):
"This is not training."

That's the message
we don't really want to hear

during a six-month mission.

♪ ♪

SCOVILLE:
If a space station spins
too fast,

this could introduce
several potential hazards.

If it were to flip upside down,

now our antennas,
which are normally pointing

towards our communication
satellites,

are no longer pointing up.

So we risk losing communication
with the space station.

35 meters across and 70 meters
long and very, very fragile.

The acceleration
of rotating them

will generate centrifugal force,

and that can tear everything
apart.

SCOVILLE:
We have docking mechanisms

with the crew vehicles
that are used as lifeboats.

If we spin too fast,

if we had to undock
in an emergency,

those hooks might jam.

PESQUET (translated):
It's really very, very
dangerous.

A space station is very fragile.

It doesn't even have
to carry its weight.

NARRATOR:
The advantage of building a
station in the vacuum of space

is that you don't have to fight
things like wind and gravity,

so the structure
can be less sturdy.

The problem is,
any unexpected twisting

could break it into pieces.

Ground Control desperately
needs to understand

what is causing the I.S.S.
to turn.

SCOVILLE:
So one of my first questions

was to my life support officer.

(over radio): Are we maintaining
cabin atmosphere?

Okay, what about
cooling systems?

NARRATOR:
The team ticks off a checklist

of possible causes...

(man speaking on radio)

...until a plausible
suspect emerges.

SCOVILLE: One of the main and
most likely candidates was

that the Nauka module
was firing thrusters.

NARRATOR:
A software error on the Nauka

means that it doesn't recognize

it has successfully connected
to the I.S.S.

(translated):
And so it will try

to establish its orientation,
to move,

to capture the sun,
to recharge its solar panels.

The problem is, it starts to
take the whole station with it.

NARRATOR:
Nauka's thrusters start firing,

trying to pull away
from the space station

it is now securely docked to.

MAN (over radio):
Station, Houston on 2.

We are out of attitude by at
least 45 degrees and increasing.

NARRATOR:
Four huge gyroscopes
on board the I.S.S.

keep the station in position.

As the Russian thrusters fight
with the space station's gyros,

there's concern that the joints
of the aging ship

can't take the strain.

So the decision is made

to shut the gyros down...
(alarm beeping)

...reducing the stress
on the attachment points

that connect
the station's modules together.

The I.S.S. is now in free drift.

And there's
an added complication.

SCOVILLE:
Unfortunately,

if the station was physically
over the Russian ground sites.

As it was,
we were just heading off

of the eastern coast of Russia
over the Pacific.

And so we had no insight,
no telemetry, no data,

and no ability to command it
or turn it off.

We weren't going to get that
back for about 90 minutes.

NARRATOR:
In Houston,
flight controllers listen

to real-time translations
of the communications

between Moscow's Mission Control

and the cosmonauts
on board the station.

(people speaking Russian
over radio)

TRANSLATOR:
Oleg, please,

can, can you confirm or not

whether MLM thrusters
are still firing?

Do you see,

do you hear anything?

(people speaking Russian)

TRANSLATOR: I can confirm that
the thrusters are still firing.

They have just fired,
and we could feel it.

(translated):
At the time, I don't know
if we fully realized

the seriousness
of the situation.

♪ ♪

SCOVILLE:
We've got one-and-a-half hours

to ride this thing out

before we're going to be able to
completely stabilize the system.

At this point,
in order to assure

we had every advantage we could,

I declared a spacecraft
emergency.

NARRATOR:
A spacecraft emergency

ensures that all attention
is focused

on the operation at hand.

♪ ♪

All available ground antennas
across the U.S.

now attempt to make contact
with the I.S.S.

TRANSLATOR (over radio):
Oleg, we did not copy your last.

Could you repeat your last?

NARRATOR:
But still,

the connection
between the ground and space

is patchy and unpredictable.

(people speaking on radio)

And, with the whole I.S.S.
structure now turning away

from its communications
satellites...

(people speaking on radio)

...U.S. operations are about
to lose contact with the crew.

(alarm beeping)

SCOVILLE:
We were tracking
the space station spin,

and we could predict
we had minutes

to communicate several steps
of procedure to the crew

before we were going
to run out of time.

PESQUET (translated):
Step number one,

make sure to secure everything
that is outside the station

that can move, that can rotate.

(man speaking on radio)

NARRATOR:
The crew are instructed

to lock the station's radiators,

which are at risk
of shearing off,

while the solar panels
are repositioned.

♪ ♪

Meanwhile, at Mission Control,

the team formulates a plan

to fight back
against Nauka's thrusters.

MAN (over radio): We want you
to run the procedure...

♪ ♪

SCOVILLE: We knew, as the Nauka
module's thrusters were firing,

that we had to bring

a bigger lever arm,
a more powerful force,

to bear against these thrusters.

NARRATOR:
For that extra muscle,

Ground Control turns
to the Zvezda Service Module,

primary source for the I.S.S.'s
propulsion systems.

At this time, a cargo ship,
Progress 78,

is also docked to the station,

on the opposite side
to the misfiring Nauka.

Crucially, both Progress 78
and the Zvezda have thrusters.

SCOVILLE:
Now, typically,

there will be days of analysis.

In this specific case,
this was unexpected,

and so there was a little bit
of engineering judgment

that had to be applied,

recognizing that the alternative
and indecision

would have been worse.

NARRATOR: Mission Control
makes the decision to fire up

the Zvezda and Progress 78
thrusters

to set up an orbital wrestling
match with the Nauka

that they have to win.

♪ ♪

MAN (over radio): Hey, Aki,
just to update you guys,

so right now we're
in a little bit of a tug-of-war

between thrusters firing
from both the SM and the MLM.

And we're sorting through
the best course of action,

uh, right now.

At this point, we have
no further actions for you.

NARRATOR:
For nearly 45 minutes,

the I.S.S. drifts
out of control.

A combined effort of the
Zvezda and Progress 78 modules

pushes back against Nauka.

It's putting huge strain on
the space station's structure.

SCOVILLE: This was like
riding a bucking bronco

except this time,

it was in orbit
around the entire Earth.

♪ ♪

NARRATOR:
It will be another 45 minutes
before Russian controllers

can regain command
of Nauka's thrusters.

♪ ♪

But then, all of a sudden...

♪ ♪

MAN (over radio):
Aki, uh, we can report

that the MLM thrusters
are no longer firing.

We are back in attitude control.

Rates are stable.

AKIHIKO HOSHIDE: Okay, copy.

NARRATOR:
Nauka's thrusters fall silent.

Its fuel tanks have run dry.

The tug-of-war is over.

♪ ♪

SCOVILLE:
As we brought the space station
back to normal attitude,

I think we all took
a, a deep sigh of relief.

NARRATOR:
After rotating one-and-a-half
times, around 540 degrees,

mission controllers can finally
bring the station to a halt

and begin a controlled return
to its correct attitude.

SCOVILLE:
The team that I had working
in the control center that day

was an example of performance

that to this day
I will always remember.

Not because
we did everything perfect,

but because
of how we came together.

♪ ♪

NARRATOR:
Since its launch in 1998,

the I.S.S. has been humanity's
laboratory in the sky.

BUCHLI:
Over the past 25 years,

we have served
over 5,000 researchers

on the International Space
Station,

conducted over 4,000
different experiments...

...and published
right around 4,000 papers.

ALIBARUHO:
The fact that we've learned
so much,

not just about technology,
but about ourselves,

as a result of the I.S.S.,

that's a legacy that's not
to be denied

or discounted in any way.

♪ ♪

NARRATOR:
For many, the value
of the I.S.S.

goes far beyond the physical.

It's about perspective,

hope,

and the shared pursuit
of something greater.

PARMITANO:
The space station

is not just a place
where we produce science,

but it's a place of emotions.

It is a place of humanity.

A place where we brought with us
our own dreams.

♪ ♪

PESQUET (translated):
It's absolutely phenomenal.

There is a technical feat,

but I think that the dream
and the conception of the world,

a bit of multilateralism
and scientific cooperation

between the countries behind it,

which for me,
are even more beautiful.

CHARI:
A quarter-century
of peaceful cooperation,

multiple countries,

multiple organizations,

all working with the focus of
trying to make humanity better,

to me, that seems like a pretty
powerful and lasting legacy.

♪ ♪

NARRATOR:
But with aging technology

and the advent of new,
more efficient space platforms,

the station's days are numbered.

SCOVILLE:
The I.S.S. was never meant

to be a permanent structure
in space.

NARRATOR:
The International Space Station

is scheduled to begin
its final chapter in 2030.

♪ ♪

SCOVILLE:
About a year and a half before
the space station deorbits,

we will launch a crew
that will stay there for a year.

They will be in charge

of getting the last bits of
science and engineering we can

out of this facility.

♪ ♪

About six months prior
to the deorbit process,

that crew will come home,

leaving the space station
uncrewed

as its altitude starts to lower.

♪ ♪

NARRATOR:
A deorbit vehicle will attach
to the I.S.S.

and gently guide the station
into a slow, deliberate descent,

where it will enter the thick
layers of Earth's atmosphere

at speeds
over 17,000 miles per hour.

♪ ♪

Experiencing temperatures close
to 3,000 degrees Fahrenheit.

♪ ♪

SCOVILLE:
We know some of it will burn up,

but large pieces of it
will survive

through the atmospheric
re-entry,

and that's why we want
to make sure

that it's a controlled process,

so we safely hit
the Pacific Ocean.

♪ ♪

NARRATOR:
The I.S.S.'s
fiery disintegration

will be the final act
in its incredible journey.

♪ ♪

But the lessons we learn
from its time in space,

the technologies developed,

and the unity it represents

will echo
in future space exploration

for generations to come.

RENITA FINCKE:
The I.S.S. is not just

a international laboratory
that's orbiting in space.

It's much, much more than that.

♪ ♪

LAWRENCE:
No matter where we come from,

no matter the differences
in political systems

and the leaders that we have,

we really can work together.

We have that ability.

♪ ♪

CASSIDY:
It's just really fun to think

about the future
of space exploration

and to know that I was,
in a small way,

part of the International Space
Station's story.

♪ ♪

The International Space Station

is the crowning achievement
of human ingenuity so far.

(static hissing)

(device beeps)

♪ ♪

♪ ♪

♪ ♪

♪ ♪

♪ ♪

♪ ♪