Nova (1974–…): Season 48, Episode 5 - Looking for Life on Mars - full transcript

Follow along as NASA launches the Mars 2020 mission, perhaps the most ambitious hunt yet for signs of ancient life on Mars.

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NARRATOR: February 18, 2021.

NASA's newest rover,

one of the most sophisticated
planetary probes ever built,

is approaching Mars

on an epic quest to hunt
for life beyond Earth.

SWATI MOHAN: We are under
a minute

from cruise stage separation.

130 million miles away,

a team of researchers anxiously

MOHAN: Heading alignment.

NARRATOR: as Perseverance
attempts to land

where no rover
has dared land before...

Inside a crater

that might be filled
with ancient Martian life,

but is definitely filled
with cliffs

and sand traps

where a rover can crash

or get stuck for good.

We're heading toward the ground

at race car speeds.

So there's no way we're going
to joystick this down.

NARRATOR: For the first time in
the history of Mars exploration,

a rover is equipped with

the intelligence to try to steer
itself out of danger.

ELIO MORILLO: There's a very
specific timeline of events

that have to happen at the
correct time for

the entire process to succeed.

NARRATOR: Perseverance signals
its progress...

Sky crane maneuver has started.

NARRATOR: as the team
monitors every step.

If the rover manages to land in
one piece,

for about two years,
it will drill into Martian rock

that could hold evidence
of ancient life,

then collect samples
and store them.

JULIE TOWNSEND: For the first
time, we are going to collect

rock samples and bring them back
to Earth.

NARRATOR: In the future, another
rover will retrieve the samples


And through a series of
daring missions...

that sound more science fiction
than science fact...

the samples will be brought
to Earth,

where researchers
can examine them

in far greater detail.

We have this amazing technology

that can really can get those

bring them back to Earth,

and do all the really cool

that we want to do here
on Earth.

This is a very, very large

involving thousands and
thousands of people

from all over the world.

Thousands of researchers

with one shared goal.

"Looking for Life on Mars,"
right now, on "NOVA."

Did life ever exist on Mars?

And if it did,
what would that mean for us?

How special is life on Earth?

Why do we not see it
on Mars today?

Did it ever evolve on Mars?

What does it take to get life

to evolve on a planet?

That question about life

is the one that really perplexes
and, I think, really drives us.

Something about our desire
to not be alone

keeps pushing us forward in the
search for life.

I like to call it
"CSI: Mars," right?

You know, it's, it's literally
this investigation

where you're finding all these
little clues

to put together your story.

NARRATOR: The tale of our
celestial neighbor, Mars.

The red planet.

It captures the imagination.

Thousands of images paint
a picture

of a barren, alien world.

At the same time,
there's something about Mars

that's strangely familiar.

I was born on the Navajo Nation.

It's a high desert area

that actually has rolling
desert hills,

canyons, and rock formations,
and mountains,

and all of that looks like the
Martian landscape.

DIANA TRUJILLO: When I look at
the pictures of Mars,

I see the Mojave Desert, right?

Without the cactus.

But I can't tell the difference
if this image

is from the Mojave Desert
or if this is from Mars.

To me, it makes me want
to know more.

It makes me want to know,
you know, what happened to Mars,

or was there life there?


NARRATOR: Can the Perseverance
rover finally answer

this question?

We've been searching for the
remnants of life

on the red planet for decades,

from the Mariner orbiters

to the successful landings
of Viking 1and2...

...through the twin rovers
Spiritand Opportunity

that crisscrossed the planet.

MORILLO: We've been building
our knowledge

of the Martian environment

through so many decades
and so many achievements

from so many engineers
before us.

But it was the discoveries

of the most cunning robotic

to ever explore Mars,
a rover named Curiosity,

that set the stage for the

September 14, 2012,

40 days after Curiosity
landed on Mars,

it stumbled upon the unexpected.

SANJEEV GUPTA: I remember the
moment those images came down.

We were all at the
Jet Propulsion Laboratory

at the time, and we were all

around a giant computer screen,

and, and I was just gazing at
this in astonishment,

because it's not
what we had expected.

We came across a whole bunch

of cobbles,

and when we saw that,
everybody's jaw just dropped.

"Oh, my gosh, look at this,
this is perfect."

It is the classic example

of a river deposit.

Each one of those rocks,
they had to get bounced around

in some type of environment that
was going to turn them

from something that was chunky
and sharp and angular

to something that was rounded.

Rivers do that.

Rivers on Earth do that
very well.

And so when we saw this, it was
our first evidence of a river.

Evidence that water once flowed

on the surface of the
red planet.

On Earth, all life needs
water to thrive...

...from the giant blue whale

to tiny microbes.

GUPTA: The scientists on the
team have discovered

all these telltale signatures
in the rocks

that there were rivers
and ancient lakes that existed

for hundreds of thousands,
if not millions of years.

You can think of Mars

as... back in time, of course...

as being Earth's slightly
smaller, slightly colder sister.

GUPTA: Between 3.9 and 3.5
billion years ago,

we think that Mars was a warmer
and wetter place.

And what's interesting about

that is that's the same sort
of time interval

that life got going on Earth.

KEN FARLEY: We have two planets
with similar environments

at similar times.

One of them, on Earth,
is inhabited.

Why wouldn't we expect that the
one on Mars would be inhabited?

NARRATOR: Curiosityfound
evidence of a once-wet world.

But here on Earth,
for life to thrive,

it needs more than water.

It needs nutrients.

EIGENBRODE: We tend to simplify

that search for what type
of nutrients

as what we call CHNOPS.

When people say CHNOPS,
what they're saying is carbon...

Hydrogen... Nitrogen...

Oxygen... Phosphorus...


And we spell all those,

the first letter of
all those out,

it's called CHNOPS. (laughs)

These six elements make up

roughly 99% of the mass
of the human body.

In fact, they make up about
99% of the mass

of all living things.

If life, as we know it,
ever existed on Mars,

finding CHNOPS was key.

Could Curiosity, a laboratory
on wheels, find CHNOPS?

The rover scooped up samples
of Martian soil

to decode its chemical

EIGENBRODE: What we found was
a diverse chemistry

that included carbon, hydrogen,

some nitrogen, oxygen,
and sulfur,

and eventually we found
some phosphorus.

There's plenty of chemical
energy available for life,

if it had ever lived there.

That's really been
the big discovery

of the Curiosityrover mission.

NARRATOR: Curiosity found the
ingredients necessary for life

to emerge, but not life itself.

FARLEY: Curiosity has not, in
fact, detected evidence

for life, because it does not
have the instruments

designed for that purpose.

NARRATOR: Perseveranceis
designed to take the next step

in Mars exploration,

as it ventures into
unexplored territory

to search for samples
of Martian rock

in Jezero Crater.

If you want to set yourself up
for success

for finding ancient life,
that is the place to go.

This orbital image reveals

what makes Jezero Crater
so intriguing.

KEN WILLIFORD: The key thing
that led us to Jezero

was this beautiful delta,
beautifully visible from orbit.

We think that delta must be
somewhere around

three billion years old
or older.

This delta sits at the end of a
beautifully expressed

sinuous river channel that came
in from the northwest,

flowing into the crater rim,
and filling up

Jezero Crater with a lake.

NARRATOR: On Earth, deltas form
where a river

and a larger body of water meet.

Sediment, brought in from the
river, drifts to the bottom.

TANJA BOSAK: The sediments that

the river carries are...

They really just fall out
and they settle down.

EIGENBRODE: It creates a mud
layer at the bottom.

Year after year after year after
year, it creates these.

NARRATOR: Take some of that
earthly delta mud,

put it under a microscope,

and you'll find
it's teeming with life.

Tiny microbes,

among the most ancient forms
of life on Earth,

arising billions of years
before the dinosaurs...

and far more resilient.

BOSAK: If we think about Mars
billions of years ago,

we cannot hope for any
large-scale fossils.

We can't really hope for
fossil bones.

We can't hope for
petrified wood.

We can't hope for
fossilized leaves,

because none of that
life existed even on Earth

before maybe half-a-billion
years ago.

The only life that
we can hope for

on this old, ancient Mars
is microbial.

Now, this is where it gets

because microbes are tiny.

That's what their name says,
they're microscopic.

And we can't really take
microscopes to Mars,

but what we can look for
are rocks

that can be shaped
by microbial processes.

And that's what the team

hopes Perseverancewill find:

fossilized microbes,
buried in the ancient rocks

of Jezero Crater.

FARLEY: There are a lot of very
interesting debates

among the members of the
science team

trying to figure out,
which rocks should we sample?

What should we be looking for?

(camera clicks)

And we have

one example, only one example,
and that's Earth.

NARRATOR: So the Perseverance
science team set out

to study the clues Earth has
to offer

in rocks about the same age

as the ones they will search
for in Jezero Crater.

FARLEY: We went to this location

in Western Australia where the
oldest evidence of life occurs,

just so we could see what
it actually looks like.

MAN: There are ripples around
the side of...

NARRATOR: The strange, rippled
layers of these rocks,

known as stromatolites,

are actually the remnants
of a form

of ancient microbial life.

In a stromatolite, you'll see
there's lots of convolutions.

They're bumpy and, and lumpy.

NARRATOR: Bumps and lumps
of fossilized microbes.

A fossilized community of
organisms all packaged together.

There are just a few colonies

of living stromatolites
left on Earth.

They look like rocks,

but just beneath the surface
are layers of bacteria.

WILLIFORD: These often form in
shallow-water environments

where the microbes sort of

have something to live on, and
they pile up in these layers,

one on top of the other,
a layer of gooey microbes,

bacterial cells that have this
sort of mucous-y,

gooey substance.

That gooey substance

traps sediment, mud or sand,
that flows on top of it.

And then they grow on top
of that again.

And that process repeats.

NARRATOR: By studying these

ancient stromatolites,

the team hopes to gain
a deeper understanding

of what to hunt for on Mars.

When we went out
and looked at these rocks,

I was very surprised
how obvious it was

that the structures that we were
looking at were, first of all,

very unusual and very likely

to be biogenic,
produced by life.

This is a kind of a feature

that we could see in
Jezero Crater with the cameras

that we are carrying with us
on the Perseverancerover.

This rover has a ton of

we are carrying 23 cameras.

Color cameras, zoom cameras,

black-and-white cameras...
You name it, right?

Cameras that can see up to,

the size of a grain of salt,
and so

they're all over
the place on the rover, right?

On the front, on the back, on
the top, on the arm.

We have two in the robotic arm
that are awesome.

One of them is Pixl
and the other one,

which I love the name,
is Sherloc and Watson.

You can guess from the name

of Sherloc and Watson
that the whole point

of those instrument is to
investigate, right?

What is the chemical composition
of that target?

BOSAK: We don't have geologists

who can bang their hammers
on the rocks

or, or take their lenses,
or maybe there's even,

you could drop some vinegar to
see what minerals are present...

we can't do that.

But we do have a lot of
instruments that tell us

what is in those rocks.

NARRATOR: Perseverancewill also
be on the lookout

for another ancient rock
in Jezero Crater,

one that is as elusive
as it is appealing.

WILLIFORD: This is a piece of
what we would call black chert.

Chert is such a fine-grained

If you look really close,

you can see some sort of
blotchy, black stuff

in the interior of this
gray rock.

And that black stuff,
that blotchy, black stuff

is actual fossilized
bacterial cells.

This is a type of rock
that we would

absolutely love to encounter
on Mars.

The tough part is that chert is
very, very, very hard to drill.

So it'll be a tough decision.

If we see a rock like this,
we would,

we would probably be willing

to give up an entire drill bit.

The payoff is potentially so

because we could, you know,

maybe bring back fossil
Martian cells.

NARRATOR: Even if Perseverance
finds rocks that look promising,

it's not equipped to verify
ancient microbes.

For that, the Martian rock
would need

to be studied back on Earth.

Collecting samples on Mars
and bringing them back to Earth

is one of the most complex
things we've tried to do

with one of our robots...
This is a sample tube,

and on board Perseverance
are over 40 of these.

And the goal is to fill
each one of them

with a sample of Mars rock.

NARRATOR: A sample tube is
loaded inside a drill

at the end of the rover's arm.

YAZZIE: We had to come up with
an entirely unique design

to drill into a lot of
different rocks

and be able to extract
core samples that aren't broken

into too many pieces,
that hasn't turned into powder.

So it's actually a very
sophisticated mechanism.

After we're done drilling the
depth that we want to,

we do one final motion
to extract the core

from the inside of the rock.

NARRATOR: Now the sample tube,
filled with Martian rock,

is brought back on board
the rover.

We take the robotic arm

with Martian sample inside of it

and we dock it inside the belly
of the rover.


Where we have another small
robotic arm

that extracts the tube...


...and takes it through a series
of stations.

SAMUELS: We want to inspect it.

We want to figure out how much
volume we may have collected,

take some pictures of it.

And then we seal that tube

and then go put it back
into our storage rack.

TRUJILLO: So all of that gets
done internal to the belly

of the rover with a little arm

that, he's moving it around,
which is insane.

NARRATOR: It took seven years

to design, test, and build

this one-of-a-kind
sampling system.

We've put a lot into this rover,

and we are very invested in
it working

when it gets to Mars.

And so we kind of wait

with bated breath,
and we do the best we can,

and we do tons and tons
of testing.

And we, we hope that it is

NARRATOR: Inside this massive
clean room at JPL,

the sampling system,

along with seven science

are carefully loaded inside
the S.U.V.-size rover.

Throughout this process,

the spacecraft must be kept
impeccably clean,

down to the microbe.

LYNCH: We don't want to send

an expensive vehicle
like Perseverance

to Mars and then just detect

because we didn't work to make
sure that

we kept the spacecraft
and the instruments,

and everything that it touches,
as clean as possible.

COOPER: You want to have

a nice pristine sample without
any Earth contamination,

so that's why we work
really hard

to keep that spacecraft clean.

Moogega Cooper is responsible

for hunting down earthly
microbes that could hitch a ride

to Mars on the spacecraft.

Especially the hardy ones.

COOPER: The microbes that we're
talking about are

so resilient, they could
possibly survive all of the

radiation in space, U.V.,
the temperature swings,

journeying to Mars,

and possibly back.

So we have to sample
the hardware over time,

and we use either swabs

or wipes to collect samples,

lift them off of the surface,
and we bring it to our lab

and we put them in these
petri dishes.

We have to give them food

so that the colonies grow large
enough so that

we can see them, and know that
they're present

on our petri dish.

If some hardy microbes flourish,

the surface is cleaned
with isopropyl alcohol.

Over the course of the mission,

we've taken 16,681 wipes,
swabs, and air samples

of the spacecraft and
the surrounding environment.

Pretty... Pretty good job.

NARRATOR: But there's one part
of the rover

that needs to be as clean
as humanly possible.

The sample tubes that
will store Martian rock.

We had to have an environment

in which to put them together

and to handle them
and to work with them

and assemble them.

We built an entirely new
clean room,

the cleanest environments
we've ever had at JPL.

We take a normal clean room

and we start breaking
everything down

to understand additional sources
of contamination

and how do we make that room
even cleaner.

The gloves that they use,

how many layers of gloves
that they have,

how often they need to change

how often they have to change
the gowns,

when we can reuse things.

Even the computers that are used
in there.

We can't bring
cell phones into that room.

We can't bring everyday objects

that you normally associate
with how you do your job

into an environment that is that
sterile and that clean.

The sample tube itself looks
very similar to a test tube,

but that really belies
the complexity of the design

and the features that are built
into the sample tube

to help prevent contamination.

The gold coating is a mixture
of titanium and nitrogen

especially engineered in order
to prevent organic compounds

from sticking to the surface,
and that's on the outside

of the sample tube and also
inside the sample tube.

These sample tubes are the
cleanest things

that we've ever sent

to another planet by far.

In fact, these sample tubes are

the cleanest thing on Earth.

NARRATOR: March 2020.

The COVID-19 pandemic triggers

shutdowns across the country...

including at NASA's
Jet Propulsion Laboratory.

Life as we know it
comes to a grinding halt.

COOPER: It's hard enough to
build spacecraft, but on top of

that, as we were approaching

the COVID-19 pandemic was
surging in parallel.

Time is of the essence.

It's just four months
before launch.

A limited number of essential

are permitted on site.

COOPER: It's very difficult

to control whether or not face
masks are worn

outside of the workplace

It's easy when you're in a
clean room, that's what you do.

You wear your face masks,
you wear your bunny suits.

We actually felt safer
in the clean room than we did

in the regular environment.

Despite the team's best efforts,

it's unclear whether they'll be

ready to launch on time.

SAMUELS: We launch to Mars

typically every two years.

And if we miss that opportunity,

you know, that,
that's a long time to wait.

YAZZIE: One thing to understand
about sending something to Mars

is that we have a very short
launch window.

Mars takes about two Earth years
to orbit the Sun,

and every two years, Mars
and the Earth are close enough

to each other, and that's when
we launch missions

between the two planets.

And if we miss this launch

for any reason, we would have
to wait two years

until we could try again.

NARRATOR: And that wait could
cost half-a-billion dollars.

TRUJILLO: The team recognized

we are already on the rails,

We're about to take off.

Let's just get the job done.

If we focus on this target,

maybe we'll unite the whole
team, as well.

And in a way, also give hope
to everybody,

not only on the U.S., but also
around the world, that

we still can manage to focus
on a mission

and focus on a bigger objective,
and then pull it off.

FARLEY: For me, the bright spot

of COVID was actually seeing the
team that we had pull together

and actually get it done.

It's kind of miraculous that
we got to the launch pad.

Before Perseverance is launched,

members of the team install
this plaque

to honor healthcare workers.

It's a constant reminder that

there are people, you know,
making sacrifices to make sure

everybody is safe and healthy.

From America's shore

to Jezero Crater on Mars.

We'll begin with the launch
of this

Atlas V rocket...

The day has finally arrived.

is on the launch pad.

On a nearby beach, team member

Elio Morillo,

along with friends

and his mom, have come
to watch the launch.

This is my first mission,

and I'm about to see it
take off to Mars.

I can't describe how

excited and scared and nervous

I am at the same time.

I'm really proud to be part
of this team.

And despite the pandemic,

we have persevered through
this together.

NARRATOR: Meanwhile...

Grabbed my security blanket.

Let's see if she'll let me...

NARRATOR: Other team members,
like Ian Clark,

along with his dog Pixl,

nervously watch the launch
from home.

MAN (on computer):
Launch director.

LD is go, and you have
permission to launch.

The bouncing in my leg
is accelerating

as we're getting closer.

(chatter on computer)

28 seconds,
28 seconds to launch.


seven, six, five, four,
engine ignition, two...

WOMAN: Zero.

Release... and lift off.



WOMAN: Damn!


WOMAN: There it is.

There it is, there it is!




(Morillo exclaims)

I'm a little bit speechless

with what just happened.

It's surreal, I, I don't know
what else to say

other than, I still can't
believe that I just saw that.

It's pretty magical,
you know, it's, uh...

What we get to do.

(laughter, applause)

MORILLO: I'm terrified and
really excited, but it's scary.

NARRATOR: Perseveranceis on its
seven-month journey to Mars.

But for Elio Morillo,

the hardest work has just begun.

(scooter starts)

We're working around the clock.

Tonight, for example,
I have to go in at 7:00

and I won't leave probably till
4:00 in the morning.

And that's kind of the nature
of the work to make sure

we prepare for our landing

on the red planet.

We are working with
the Earth version

of Perseverance,

which we've calledOptimism.

The rover and the computer
that it has on board

is exactly the same as the one
that's onPerseverance.

My job is, is literally the one
they portray

in, in "The Martian."

Is this the replica?
- This is her.

Okay, let's see it.

MORILLO: Where there's a lab
that has the Earth versions

of all the vehicles...

I work in the real lab
that has the Earth version

of all the vehicles
that have gone to Mars.

It's called the Mars Yard.

Here, Optimism,
Perseverance's twin,

faces some of the same
challenges Perseverance

will face on Mars.

The only real way to do that
is through simulation.

So the Mars Yard is where
we actually perform driving.

We have soil that kind of looks
like Martian sand, if you will.

There are rocks that
we replicate.

And we have slopes, as well,
so that we can climb the vehicle

on the slopes.

In doing that,

we typically will find bugs.

NARRATOR: Glitches in the
software, the rover's brain.

And as we come up with fixes,

we will uplink those fixes
to the real vehicle.

And that is the purpose
of my team.

So that, hopefully,
we find these issues

before they happen
on the real vehicle.

In case things go wrong, we
better figure out how to fix it

through software,

because at this point in time,
we can't send mechanics to Mars.

I'm an avid user
of social media.

And some of the images
I've posted are

of myself working
on the vehicle.

I think personally,

being a Hispanic man, it's very
important for people like me

to understand that there are
people that look and sound

like me that are working on
such technologies.

That is why I share what I do.

And I like to show people

what we're doing,
because it's pretty unique.

NARRATOR: A few months after
Perseverance lands

on the red planet,

it will drop a special
little package on the surface

that could revolutionize the
future of space exploration.

A tiny copter named Ingenuity

could be the first aircraft
to fly on another planet.

When we first proposed it,

there were a number of
naysayers, even at JPL,

who said, "Oh, this thing can
never fly."

I thought it was going to be

every step of the way.

In fact, at the beginning,

it was the question of even

Can it be done?

NARRATOR: What makes flying on
Mars so challenging

is its extremely thin

100 times thinner than Earth's.

The thinner the atmosphere,
the harder it is

for a helicopter to generate

Fundamentally, a helicopter

flies, you know,
by first generating lift,

and the lift is generated
by the blades

pushing the air,

and that provides the lift.

NARRATOR: On helicopters,
the blades are curved on top,

and are also angled to redirect
the airflow downward.

Because of this design,
as they rotate,

the air pressure on top of
the blades decreases

and the air pressure underneath
the blades increases.

That difference in pressure
pushes the helicopter up.

Earth's dense, thick atmosphere
helps make lift possible.

In order to fly on Mars,

the team had to find a way
to compensate

for its thin atmosphere.

To rethink the physics
of flight.

AUNG: You have to build a
vehicle that has a large blade,
you know,

significantly large proportional
to the size of the vehicle.

And the blades have to spin
very fast

and the vehicle has to be
very light.

NARRATOR: In 2018, the team took
their copter on a test run.

This special chamber has had
most of the air sucked out of it

so it can accurately mimic
the thin atmosphere of Mars.

AUNG: This is a moment of truth.

You send the command,

the helicopter is sitting
on the ground,

and it starts spinning.

And the danger was,
is it going to start, you know,

skittering across
the, the chamber floor?

(blades whirring)

The vehicle was perfect.

It was balanced so perfectly.

(blades whirring)

Our minds go back to
what the Wright brothers

must have gone through.

The first moment
they took flight,

they must have felt

the emotion, the feeling,

the reward they were looking

(blades whirring)

It's been a long journey.

We've done all the testing

here on Earth,
and now it's time to go to Mars

and prove that this thing
can really fly

in the actual environment
of Mars.

If all works as planned,

Ingenuity will take a series of
flights over about 30 days,

venturing farther
with each flight.

When astronauts get to Mars,

you know, in the future,

being able to scout and survey

and just having
the aerial dimension

will be crucial.

BALARAM: To make the whole
planet accessible

through a new form of mobility

is going to be transforming
in terms of what it does

for exploration.


NARRATOR: Another passenger on

could help turn our sci-fi
dreams of human exploration

into a reality.

In fact, in the feature film

"The Martian,"

Mark Watney couldn't have
survived without it.

In the movie "The Martian,"

there was a mention of a device
called an oxygenator.

Everything here
that's keeping me alive...

The oxygenator,
the water reclaimer...

Which we like to think of

as the, maybe the
great-great-grandchild of Moxie.

This little gold box named Moxie

will test whether it's possible
to take deadly Martian air

and create breathable air.

The air on Mars
is not only thin,

it's rich with carbon dioxide...

HOFFMAN: So what we're trying to
do with Moxie is to take

a carbon dioxide molecule...

CO2, one carbon,
two oxygen atoms...

and split off one of those
oxygen atoms.

NARRATOR: An oxygen atom doesn't
like to be alone.

After it breaks away
from the carbon dioxide,

it joins with another oxygen
atom, creating O2,

which is in the air
that we breathe.

Here on Earth, the atmosphere
has plenty of O2,

thanks to photosynthesis.

We take all that oxygen
for granted.

When we're on Mars,

we have to make the best
of what we've got

and get our oxygen

out of that carbon dioxide.

NARRATOR: Breathable oxygen

will be crucial for humans
to survive on Mars.

HOFFMAN: There's no question,

if I were going to Mars,
I would want oxygen to breathe.

But that's not anywhere near

the, the major requirement for

Assuming that I want to leave
the surface of Mars

and get back to orbit and,
and catch my ride home to Earth,

I'm going to need
a lot of propellant in a rocket

to get me off the surface
of Mars.

Tens of tons, in fact.

Whether you have a campfire,

whether you have
an internal combustion engine

in a car or a truck...

anytime you'd want
to burn something,

you need two things:

you need a fuel
and you need oxygen.

NARRATOR: To take off from the
surface of Mars with a crew

of four, in a rocket about the
size of this pickup truck,

how much fuel and oxygen
do you need?

Oh, we need about
seven tons of fuel.

That's a lot of fuel.

And we need about 25 tons

of liquid oxygen
to burn all that fuel.

To picture how much that weighs,

we can start with
a five-gallon jug of water,

the kind that we put on top of
the water coolers.

If we wanted to put
that much liquid oxygen

in those water jugs,

we would have over 1,300
of those jugs.

So imagine putting 1,320

water bottles in the back
of this truck.

That would be tens-of-feet-high
stack of water bottles.

Too much even for the
water bottle delivery van,

never mind this little pickup.

That oxygen turns out to be
the single heaviest thing

we would need to take

on a mission to Mars
with astronauts.

It dominates the cost and the
complexity of the mission.

So what if we can start
living off the land?

By saying, "We're not going
to bring any oxygen with us.

"We're going to make it on Mars
and use the oxygen that we make

"to fuel the rocket that will
take our astronauts home,

that will take Mark Watney

NARRATOR: If Moxie can
efficiently create burnable

oxygen, then the sci-fi dream
of human exploration of Mars

may become a reality.

FARLEY: It's clear that
the United States

is putting in a big effort

to send astronauts to Mars.

And, and the technologies
that we are demonstrating

are going to make that easier.

NARRATOR: Perseverance will test
technology that will take

exploration into the future
as it collects samples

of Martian rock.

Once it's done,
how will these samples

make their way back home?

Return really is an

international program between

KELLY GEELEN: We all come from
different backgrounds

and we have, of course,
different roles

to play in the bigger picture.

But everybody is working towards
the same goal.

If you think about it,
it's amazing

how a collaboration across
the globe can come together

to do such an amazing thing.

NARRATOR: Current plans call for
another lander to travel to Mars

within a decade,

and a multi-part mission

to bring the sample tubes
back to Earth will begin.

ALASTAIR WAYMAN: It would be a
big risk, a big gamble,

to bet the whole of Mars Sample
Return on the fact that

Perseverance would still be
alive and fully functional

after almost a decade
on the surface of Mars.

NARRATOR: So researchers across
the globe must prepare

for different scenarios.

The Perseverance rover has the
possibility to either hang on

to sample tubes or drop them
onto the surface.

NARRATOR: Just north of London,

engineers at Airbus

are preparing for one of these

Meet Fetch.

Think of this little rover as a
celestial messenger service.

VIJENDRAN: Perseverance will
drop the sample tubes

on the surface of Mars,

drive a little bit away,
and take a lot of good photos

to document exactly where
the sample has landed.

And we will be able to direct

the Sample Fetch Rover
to the general area

within a meter or so of the
actual samples on the surface.

NARRATOR: Once Fetch gets close,
it will need to find

the sample tubes on its own.

WAYMAN: We need to have
autonomous systems on board

that can take a picture
of the scene in front of it,

identify what's a rock,

identify what's a crack,

identify what is the tubes.

NARRATOR: Fetch starts by taking
a picture of the general area

where the tubes should be.

So this is the raw image
that we've taken right as we've

approached the sample tubes.

You can see on the raw image
that there's clearly a number

of tubes dotted around
the terrain,

as well as a couple of rocks.

NARRATOR: Through a series of
steps, it decodes the scene,

homing in on the tubes based on
their shape and color.

WAYMAN: In the times that the
tubes are on the surface,

there will certainly be some
form of dust deposition on them.

Sand might build up adrift
on one side of the tubes.

But it's not going to be
a thick coating

that completely obscures it.

NARRATOR: Fetch comes up with a
plan to grab the tubes,

but it can't do it
without Delian,

a savvy robotic arm
being developed in Italy.

This lightweight arm is equipped
with a brain of its own.

This operation must be performed

with the vision system.

NARRATOR: In other words,
the brain of the rover

and the brain of the arm
work together to locate

and pick up the samples.

WAYMAN: Being able to do that
is something that's,

that's completely new,
completely novel.

It's not been done on any
Mars missions before.

So it's something that's
a key development challenge

that, that we're working on.

NARRATOR: Once it collects the
tubes, Fetch will bring them

to a pint-sized rocket.

The most challenging element

of that whole architecture
is going to be launching

a rocket off of Mars.

That is super-ambitious.

That will be a first.

NARRATOR: The rocket, designed
by NASA, will release the

samples, which will be grabbed
by another orbiter,

designed by ESA.

GEELEN: The Earth Return Orbiter

is hurtling around the Martian
planet by 7,600 miles per hour.

The job for an orbiter is to
slightly adjust its velocity

to make sure that we can capture
this basketball inside a hoop.

We'll have some sort of
trap door that opens,

and then we'll basically
swallow this basketball up

and put it into our spacecraft.

HALDEMAN: Through various stages
of mechanisms and airlocks,

if you will, put it inside
a Earth entry vehicle

that itself will be clean,

and we will have these
various layers that will protect

the Earth when we bring that
sample back from Mars.

NARRATOR: To protect Earth from
whatever the samples contain.

PITTS: Incredible safeguards
are being developed

to make sure that any object
brought from Mars

remains in an environment
that is completely cut off

from Earth environment in every
possible instance and manner.

The nice thing about
sample return is, we've done it

in the past with the moon...

the Apollo samples.

Samples were treated
as hazardous

until they could prove
that it did not affect

humans negatively.

And the same thing will be done
for any sample return mission.

The items are treated
as potentially hazardous

until we know that it's safe.

You want to be overly cautious,

you want to sure that you prove
without a shadow of a doubt

that it is not hazardous
to humans.

NARRATOR: But long before
we would confront

any potential danger
from Martian samples,

Perseverance must land where no
rover has dared land before.

Back in May 2019,
in the heart of Death Valley,

a team of engineers test
a new autonomous landing system

they hope will give their rover
the ability

to steer out of trouble...

to be its own pilot.

We get one chance.

We have no opportunity
to fix it.

And it has to work
the very first time.

NARRATOR: Inside this trailer is
a makeshift mission headquarters

where they will monitor
if the new landing system

actually works.

Our previous missions
really only had one computer,

one brain, that was doing
the entire entry, descent,

and landing sequence.

Now we have two.

NARRATOR: Two brains that must
work hand in hand to guide

the rover to land safely near
the delta of Jezero Crater.

CHEN: That delta has created
this cliff that's, like,

60 to 80 meters tall,

kind of along the lines
of how tall we're seeing

the terrain behind us.

NARRATOR: The rover must land
close to it, not crash into it.

To test the rover's new brains,

the team secures one
on the nose of a helicopter

and the other behind
the cockpit.

The helicopter, and brains,

take off...

...heading to a section
of Death Valley

that looks remarkably like

the surface of Mars.


when we do these tests,
you start out very nervous,

and often things break,

and you have to fix them.

MOHAN: We're really trying to
find the unknown unknowns.

What if we didn't think of
something that

really will affect the mission?

Hammer, do you read me?

NARRATOR: The helicopter goes
above 10,000 feet...

CHEN: Which is pretty high
for a helicopter to fly.

NARRATOR: High enough for the
crew to need oxygen,

and around the same height
where Perseverance will start

to use its pilot's brain
to land on Mars.

CHEN: Just like you and I
can take a map and look at it,

and then look around and see
different landmarks,

and see what's, you know, what's
where on the map,

the rover figures out
where it is based on knowing

where all the landmarks are
in the map

and then identifying them.

NARRATOR: A lot like the job

Pete Conrad and Alan Bean faced

when they landed on the moon
on the Apollo 12 mission.

ASTRONAUT (on radio):
Okay, we're at 19,000 feet.

I got some kind of a horizon
out there.

I got some craters, too, but
I don't know where I am yet.

CHEN: They were looking out
the window

at different craters and
different features on the moon.

ASTRONAUT (on radio):
I think I see my crater.

CHEN: That they knew of from
maps of the moon.

ASTRONAUT (on radio):
There it is!

There it is, oh, my God, right
down the middle of the road!

CHEN: They figured out
where they were.

You know, we're doing
the same thing that

those astronauts did on
Apollo 12, just on Mars.

MOHAN: The vision computer
is telling the rover computer,

"Here's where I am, here's
where I am, here's where I am."

The rover computer
takes where we are,

figures out where we can go,

and picks the safest spot

in the place where we can
actually reach.

And it does all of that
in the snap of a finger.

NARRATOR: In the trailer,
the team tracks

the brains' progress.

So on this side, we have a map
that we've made

of our landing site
that we're matching to,

and this is the image
that's taken on board.

NARRATOR: The squares on the
monitors represent landmarks.

The colors tell them if the
brain on the helicopter

is correctly identifying
those landmarks

and matching them to its map.

JOHNSON: So green ones are ones
that are good,

that we matched correctly,

that the system believes
are correct.

After six runs over the desert,

there's plenty of green
on the map.

The rover's brain appears to be
up to the task.

But will it work on Mars?

February 18, 2021.

Almost two years after their
test run in Death Valley...

MOHAN: Standing by for cruise
stage separation.

NARRATOR: the team attempts
to land their rover in Jezero

Crater under circumstances no
one could have prepared for.

Because the pandemic still rages
across the country,

many team members watch
from the safety of home.

YAZZIE: I'm feeling really
nervous and excited.

The past five years of my life

has been spent working
on this project.

I wish someone could hold
my hand.

BOSAK: Like everything in life,

you get up

and there's no guarantee that
your day will go well.

3:48 p.m. Eastern Standard Time.

Perseverance begins its descent.

MOHAN: We have confirmation
of entry interface.

As soon as the spacecraft

hits the top of the atmosphere,

it's minutes between that moment

and landing on the surface
of Mars.

NARRATOR: Although there are
cameras on board,

the team can't see any imagery
during landing.

MOHAN: Navigation has confirmed
that the parachute has deployed

and we are seeing significant

The parachute has deployed.

When the parachutes opened,

that's big, because you slow
down a lot with that one.

CHEN: Even though we're under a
huge parachute,

we're still descending at about
200 miles an hour.

That's actually a little faster
than, than I'd be going

if I jumped out of a plane and
dove headfirst

without a parachute.

MOHAN: Perseverance has now
slowed to subsonic speeds

and the heat shield has been

Once the heat shield falls away,

our lander vision system is
taking pictures of the surface,

trying to figure out where it
wants to land.

We have ten seconds to do that.

Things happen real fast
after that.

The vehicle drops itself into,
like, free fall,

turns on the retro-rockets.

Sky crane maneuver has started.

The rover slowly was tethered
down to the surface.

It was an incredible, you know,
few moments of anticipation.

TRUJILLO: You want to hear it,
you're waiting for it,

and then they call it.

MOHAN: Touchdown confirmed.

Perseverance safely
on the surface of Mars.

Wow. Whew!

(cheering, Mohan continues)

BOSAK: Disbelief, excited.

It is incredible.
It is incredible.

Oh, my gosh.




As I was celebrating,
the image comes in.

There's a picture!

I just could not believe it,

that Mars was saying hello to
Perseverance so quickly.

You want to see the dirt,

you want to see the dust
on the wheels.

It's real, it actually happened.

I just want to hug somebody!

NARRATOR: Later, actual video of
the landing finally comes in.

CLARK: This is just insanely
awesome footage.

James Cameron,
eat your heart out.


Just to see how utterly amazing
all of this engineering is,

and all of the stuff that went
into making this happen.

The ones and zeros,

and the forces and accelerations
and rates,

that doesn't really do justice.

That sort of numerical purity
doesn't do justice

to all of the emotion
and humanity

that went into making something
like this happen.

TRUJILLO: We're not landing as a
city or as a country,

we're landing as the blue
planet, right?

And the blue planet is going to
the red planet,

and we're going to be exploring
it together.

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