Original subtitles

NARRATOR: In 2002, Mars was a spacecraft graveyard.

STEVE: At that time two out of three of the missions

that had flown had failed.

NARRATOR: Spirit and Opportunity were up next,

and they were in trouble.

MAN (off screen): Ohh!

-ADAM: Well, the drop was successful. -MAN: Yeah.

The fact that the parachute exploded, not a good thing.

STEVE: To me it's a miracle that they got to Mars at all.

NARRATOR: But they did, and then they just wouldn't quit.

SCOTT: Betting against the rovers is a good way to lose money.

I don't do it.

NARRATOR: That was 15 years ago.

JOHN: This is like a car going a million miles without an oil change.

I mean, it's just phenomenal.

NARRATOR: Now their mission is over,

and they've opened the Martian frontier for good.

ADAM: Their persistence and the discoveries,

meant we were going back.

NARRATOR: Spirit and Opportunity,

the legendary rovers that conquered Mars.

Expected to last a few months, they lasted years.

They climbed mountains and crater walls,

survived dust storms, frigid nights, and broken wheels.

Intrepid explorers,

destined for greatness from the day they were conceived.

At least, that's the way it seems now.

STEVE: It was always gonna happen.

It was always gonna be a big success,

it was nothing like that at the start.

I-I-I didn't even know if we were gonna get to Cape Canaveral.

If we were gonna get to the launch pad.

There were times when it looked like we were just dead in the water.

NARRATOR: In the beginning, long before they were heroes,

Spirit and Opportunity were a last ditch effort

to prove that NASA could still handle Mars.

ADAM: They started really as a...

I wouldn't say an act of desperation,

but we had our backs against the wall.

NARRATOR: In 1999, NASA suffered two embarrassing failures on Mars,

an orbiter that lost its way thanks to a mix-up

between English and metric units,

and a lander that may have cut off its engines too soon.

ROB: We never heard from it, we never figured out what happened to it.

So, in late 1999 the Mars program was a complete shambles.

NARRATOR: Facing questions about whether Mars was still worth the risk,

NASA scrubbed most of its plans and debated the next step.

ADAM: It was in a place where we could just fold up shop

and say forget about it.

And so we looked at our playbook and we said,

"Well, what has worked for us in the recent epoch?"

Well, it was this Pathfinder mission.

NARRATOR: Mars Pathfinder was a low-budget experiment

by the Jet Propulsion Laboratory

just before the two failed missions.

ROB: We were setting out to prove that it was possible

to build something really simple and easy to land on Mars.

It was exciting, a small team,

we were doing things that no one ever had done before.

NARRATOR: The goal was to invent

a new way of landing on Mars using airbags,

with a fold-up lander inside carrying a small rover

the size of a microwave oven.

ADAM: It had been 20 years since anybody had landed on Mars.

The guys who did Pathfinder were making it up from scratch.

And they were young.

-(indistinct radio chatter) -(cheering)

NARRATOR: On the 4th of July, 1997, they pulled it off,

and the little rover was a big hit with the public.

So a Pathfinder follow-up looked like good bet

to restore confidence in Mars exploration.

NASA's Jet Propulsion Laboratory in Pasadena, California

would design and build the spacecraft,

land it on Mars, and run the mission once it got there.

And a planetary scientist named Steve Squyres

would lead the science team with a new approach to exploring Mars.

STEVE: With a couple of failures behind us

and a lot of uncertainty ahead of us

there was an enormous amount of attention focused on our mission.

I don't know what would have happened if we had failed.

It would not have been good.

NARRATOR: Squyres produced this animation

to show all the stakeholders how everything was supposed to work,

from the fiery entry into the atmosphere all the way to the ground.

STEVE: The idea was the original Pathfinder lander,

with the Pathfinder airbags,

the Pathfinder parachute,

and we'd just put something different inside.

On Mars Pathfinder, the lander was where the computer was,

that was where the brains were,

that was where the bulk of the instruments were.

The thing that made this mission different was the rovers.

What we did was put the biggest rover

we could possibly fit inside that lander.

And everything moves.

Everything travels with you as you go.

All your instruments, your power system and your computer.

And that enables true exploration.

NARRATOR: This rover would do more than just land on Mars.

It would explore, like a geologist, searching for clues

to whether Mars was ever a place that could have supported life.

NASA decided to build not one, but two of these robot geologists

to double the chances of success,

and by the time they approved the plan,

the schedule was already tight.

As they orbit the sun, Earth and Mars get close enough

to launch a mission just once every 26 months.

Miss that chance and you have to wait another 26 months.

Their deadline was the summer of 2003,

less than three years away.

STEVE: We put a team together.

I mean, it's the first time I'd done anything,

so as a rookie principal investigator I had a lot to learn.

And not much time to learn it.

We had to succeed.

That was just all there was to it.

We had to succeed.

The way we did it was by pushing an incredibly talented team

harder than they ever should have been pushed.

People were working insane hours.

We were all so committed,

that we just poured everything we had into it.

NARRATOR: One of the toughest jobs fell to the team responsible

for something that was supposed to be straightforward,

making the already proven Pathfinder landing system

work with the new rovers.

ADAM: Normally when we develop a mission we have about five years.

We only had about three years at the outset

for Spirit and Opportunity,

very tight time line.

We thought it would be okay because we were reusing

this Pathfinder landing system.

I was young and hungry with a relatively fresh-minted PhD.

I found myself positioned to lead the mechanical engineering

for the landing system,

which meant learning about parachutes and learning about airbags

and learning about rockets and heat shields.

Learning about a whole bunch of new stuff

that I hadn't learned in school.

NARRATOR: Entry, descent and landing, EDL for short,

covers everything from entering the Martian atmosphere to touchdown.

The trouble started with the Pathfinder airbags.

ADAM: We intended to use the exact same technique,

in fact the exact same airbags.

We were going to just rebuild those airbags.

NARRATOR: For the first test they found a spare set of bags

left over from Pathfinder.

ADAM: We wanted to get some testing under our belts really quickly.

We used the world's largest vacuum chamber,

100 feet tall and 75 feet wide

that we can pump down to Mars conditions

and throw these inflated bags at a simulated Martian surface,

sort of a worst-case Martian landing site.

We thought for sure that they would prove out.

-CONTROLLER (over radio): JPL? -MAN (over radio): Ready.

ADAM: We inflated them.

And we see the airbags impact the surface

and as they roll away you can see this gaping hole.

That was a bummer.

Now very quickly we said, "Oh, but those bags are old."

We have to have to build some fresh bags and come back.

And we did that.

And the next test, looking through the same cameras,

boom, a big hole as the bags roll away.

Now we're starting to feel the pressure.

NARRATOR: Then came the parachutes.

ADAM: We were testing them at National Guard Gunnery Range

south of Boise, Idaho.

We lift our test vehicle with the parachute on it.

We get it up to altitude,

we let go of the test vehicle.

We see a beautiful inflation of the parachute and then...

MAN (off screen): Ohh!

ADAM: Wow!

It's another... "oh, shoot" moment.

Uh, well, I mean, the drop was successful.

The fact that the parachute exploded, not a good thing.

MAN: Well, yeah, but I'd rather have it happen here than...

-ADAM: Mars. That's right. -MAN: Yeah.

Unfortunately, strictly speaking, that chute that just exploded

was the chute that we were planning on taking to Mars.

I believe it was that very day we had another test article,

strapped it in, put it up, dropped it...

and, boom...

MAN (off screen): Ohh!

ADAM: ...it blows up again.

And we're back to the hotel, all hands on deck,

so we can start to try and pull apart this puzzle

of why are we blowing up our parachutes.

STEVE: We're ripping airbags, we're exploding parachutes.

There's not a single thing I can do about that.

That's in the hands of capable engineers.

It's their job to go off and solve the problems.

And... all you can do is hope.

ADAM: We are scrambling

to find the time and the brainpower

to do these redesigns

of things that we thought we'd be able to fly again.

NARRATOR: It didn't take long to discover the problem.

The rovers were bigger and heavier than expected,

and had outgrown the old Pathfinder landing system.

STEVE: Once we realized how big the rover had to be

to do the job that we had agreed to have it do,

everything had to change.

We needed a new lander. We needed new airbags.

We needed new parachutes.

And that, so that busted our schedule

and, uh, busted our budget.

NARRATOR: Meanwhile, the scientists had to decide

where on Mars they should send the rovers to investigate

whether it ever had the water necessary for life.

One possibility was a flat plain called Meridiani Planum

where orbiters detected a mineral that could have formed in water.

STEVE: The Meridiani site was not a sure thing by any means.

The main thing that it had going for it,

was that it was smooth and flat

and the winds weren't very high.

And so it looked like a safe place to land and a safe place to drive around.

NARRATOR: A more exciting target was Gusev Crater

which appeared to be a dried up lake bed.

STEVE: Gusev is a big crater, 160 kilometers in diameter

and there's a dry river bed flowing into it.

Now there's no water in that river now.

There hasn't been for billions of years but it's-it's a big hole in the ground

with a dry river flowing into it.

There has to have been a lake there.

NARRATOR: The downside to Gusev was wind.

ADAM: Side winds could make our system swing in the breeze.

And if we lit our rockets up when we were swinging

we could really start moving ourselves sideways

and tear the bags apart.

NARRATOR: In Gusev Crater,

they'd have to counteract the wind with steering rockets.

And they'd need extra high performance from the airbags and parachutes.

After more than a year of intensive work,

the landing team was back at the vacuum chamber.

(indistinct radio chatter)

The airbags had been completely redesigned

to handle the worst-case scenarios on Mars.

MAN 1 (off screen): Release.

MAN 2 (off screen): That looks good.

(indistinct chatter)

(applause)

-TOM: This is awesome! -ADAM: This is awesome.

We're looking now at...

TOM (off screen): That's... I mean, it's perfect.

There's not a tear.

NARRATOR: Sacrificial layers of Vectran, a high-tech synthetic,

absorbed the impact from the rocks.

ADAM (off screen): This is a glorious pass.

NARRATOR: It worked like a bulletproof vest

protecting a double inner bladder holding the air.

ADAM: We're talking about 100 percent margin.

NARRATOR: The airbags were ready for Mars.

MAN (off screen): That is beautiful.

NARRATOR: By then the team believed they'd also solved the parachute problem,

but they still had to prove it.

ADAM: After our parachute failures in Boise

we needed a way of testing more rapidly

and in more controlled environments.

We turned to the world's largest wind tunnel.

It's a huge eight-story tall, 120-foot-wide test section.

We have a big post that sits up in the middle

and it holds our parachute canister

like the one we would use going to Mars.

NARRATOR: They'd spent months designing and building

a new set of high-performance parachutes,

and there was no time for any more setbacks.

ADAM: This test is the big deal.

You know, if we have a failure here

that's gonna start a measure of desperation

we never wanna find ourselves in, so...

NARRATOR: With the fans blowing at up to 100 miles an hour,

a parachute inflates with the same force it would experience at supersonic speed

in the thin atmosphere of Mars.

AL: ...two, one, fire.

ADAM: Come on, come on.

WAYNE: That's...

CONTROLLER (over radio): Strong oscillation on the strut.

ADAM (off screen): What is that? What is that?

It's called squidding in the parachute community.

This was the first time I'd ever seen it.

This was the first time a lot of folks had ever seen it.

We were dumbfounded as to what to do.

It's super, super, super, mega... This is super mega bummer.

So...

Just when we thought we were there,

just about to cross the finish line,

out of nowhere this thing comes.

It certainly was the worst feelings I'd had thus far in the project.

When this thing wouldn't inflate

there were dozens of possibilities

of what it might be and we didn't know what it was.

(inaudible)

I kinda thought I might be staring at the end of this project

because if we didn't find a solution for this...

we weren't going to Mars.

NARRATOR: When the parachute failed to open,

it looked like the mission might be over.

Supersonic chute problems can be nightmares to unravel.

Fortunately, this puzzle had a simple solution.

The vent hole at the top of the chute was a little too big.

When they got it right, they were back in business.

ADAM: What we discovered quite rapidly

was that this parachute, has plenty of reserve strength

and good inflation characteristics,

and this is the parachute we're gonna take to Mars.

NARRATOR: By January 2003, the parachutes were qualified for flight,

just five months before launch.

For the landing team, the biggest issues were now behind them.

But each problem solved was a reminder of how fine the line was

between success and failure.

STEVE: Each time we would hit a problem,

you know, we'd find a solution,

but you never know when you're gonna hit that one that's gonna end it all.

Any day now there may be a test failure, something goes wrong

and you go, "All right, we're done."

You know, that was scary.

NARRATOR: The rovers, science instruments, and spacecraft

had all gone through a grueling regimen of testing, and retesting,

a relentless search for anything and everything

that could possibly go wrong.

It was understood that a failed mission would be worse than no mission at all.

STEVE: Having had two missions before us fail

the view that I think existed in NASA headquarters

and in retrospect it makes a lot of sense to me now,

it made less sense at the time,

was that it would be better to simply not fly the things

than to take an unacceptable level of risk.

(thunder rumbling)

NARRATOR: Four months before launch,

the rovers moved to Kennedy Space Center in Florida.

STEVE: Everything changed when we got to Florida.

There's this do or die sense about what you're doing.

When we put the rovers together we put 'em together

and took 'em apart multiple times.

When you get to Florida you put it all together for the last time.

And every fastener that gets torqued down,

every connector that gets mated, that's it.

And you do that, even that simple task wrong

and you got a problem when you get to Mars that you can never fix.

NARRATOR: Spirit was set to launch first,

but with just a few weeks to go,

they hit a snag.

STEVE: You knew something was gonna be the last big problem.

You don't know what it's gonna be.

But our last big problem was a real big one.

NARRATOR: It involved the electrical circuits

that trigger pyros,

the explosive fasteners that release dozens of secured parts

during and after landing.

The circuits had all been tested with live pyros,

but late in the game they discovered that the next time they tried to use them,

on Mars, they might not work.

STEVE: It turns out that the way the electronics were designed

there was a chance

that some of these tests would have irreparably damaged

components inside the rover.

And the problem was our schedule was now so tight,

we were so close to the end

we couldn't even get inside the rover

to see if those components were okay or not.

The rover is ready to go to the launch pad.

It would take weeks to take the thing apart.

And it would blow our schedule. We wouldn't be able to launch.

This could threaten the whole mission.

I mean, these things could...

The rovers could end up in the Air and Space Museum over this.

Okay, if we're not able to launch these things now

it may not make sense to ever fly them.

NARRATOR: The only way to tell if any tests

had damaged the rovers

was to find all the pyros ever fired

and check them for short circuits.

STEVE: And so there was this treasure hunt,

and people were going in bags and shelves and pulling things apart,

and gradually piece by piece they were found,

the last one, the critical one that we needed to prove

that we were really okay was found yesterday.

You know, three days before launch and we're still sweating these resistors.

It was, it was awful.

NARRATOR: The deadline had arrived.

To hit their targets on Mars,

each rover would have to launch in its own three-week window,

one after the other.

STEVE: And if we didn't get off in that three-week stretch of time

we weren't gonna have a chance to launch again for 26 months.

So we had to launch in that launch window.

NARRATOR: They'd get two chances each day over a span of 40 minutes,

and anything from weather to rocket problems

could force them to scrub and lose a day of the window.

After five days of bad weather, Spirit was ready to go.

STEVE: A very, very, very large fraction of launches succeed.

But the success rate is not 100 percent

and there's a chance that you're gonna have a bad day

and everything that you worked for just, poof, it's gone.

WOMAN (off screen): Whoo!

ADAM: Everyone's excited, everyone's hot and sweaty.

Um, everyone's a little nervous.

(laughs)

MAN (over radio): NSC reports spacecraft go, spacecraft is go.

-MAN (off screen): 20 seconds. -BOY (off screen): 20 seconds.

ADAM: And there's this moment where you realize, that's it.

You know pencils down, it's over, it's going to Mars.

MAN (over radio): Nine, eight, seven, six, greenboard.

CROWD: Five, four, three, two, one.

MAN (over radio): Engines start, and lift off of the Delta II rocket

carrying the Spirit from Earth to planet Mars.

(crowd cheering)

MAN (over radio): ...vehicles responding.

KOBE: Yeah!

Get going!

(woman yelling indistinctly)

ADAM (off screen): Beautiful!

PRASUN: Come on, baby. Come on, baby.

ADAM: Keep going.

PRASUN: Come on, man.

-(indistinct) -(baby crying)

MAN (over radio): We're approaching Mach 1,

we've exceed supersonic speed

and the engine positions look good.

MAN: Awesome!

-JUAN: Cha-ching! -MAN (off screen) Cha-ching.

MAN (over radio): Onboard video system working perfectly

sending back an immaculate image.

We're now passing an altitude of four nautical miles

with a downrange distance 15.

CLCDR, LZ...

NARRATOR: Opportunity was up next.

A series of problems with the rocket had eaten up most of the launch window,

and it was close to now or never.

STEVE: This is it.

It was night, we're out on the beach.

We're ready to go.

-MAN (over radio): ...20 seconds. -STEVE: 20 seconds!

We get into the final count...

MAN (over radio): T-minus ten, nine...

STEVE: You know, you're into the ten, nine, eight, seven part of it

and you're just about to go

and at seven seconds to go they called a hold.

MAN 1 (over radio): We're going into recycle.

MAN 2 (over radio): And the clock is stopped.

STEVE: They halted the countdown seven seconds before liftoff

because of a problem with the rocket, and then you can't go.

Seven seconds!

You know, this thing is a bomb poised to explode.

And as soon as they scrubbed at T-minus seven seconds

I thought, "Oh, man, that's it."

MAN (over radio): NSC reports spacecraft go.

-STEVE: But they managed to pull it back. -MAN (over radio): Spacecraft is go.

STEVE: And 40 minutes later, off we went.

MAN (over radio): Engine position looks good,

recovering nicely from the liftoff transients.

STEVE: It was just emotionally overwhelming

in a way that I never anticipated.

MAN (over radio): And the solid rocket motors

are increasing their thrust.

STEVE: We had put so much of ourselves into those things.

For so many years.

And then you put it on top of a rocket and you launch it and it is gone.

MAN (over radio): Main engine chamber pressures holding steady,

and the vernier engines are continuing to burn well.

STEVE: It's as gone as anything you've ever done is going to be.

And it sounds strange to say, it felt strange at the time

but it was really hard to say goodbye.

MAN (over radio): And we're now past Mach 1,

the vehicle is now traveling faster than the speed of sound.

NARRATOR: After a seven-month journey from Earth,

Spirit was about to hit the top of the Martian atmosphere

at 12,000 miles an hour.

Six minutes later it would be on the ground.

MAN (over radio): Flight Director Jason Willis reporting that

all systems are go for entry, descent and landing.

We're currently...

NARRATOR: With a radio delay of almost ten minutes each way,

there could be no help from Earth.

Each step was preprogrammed in Spirit's computer.

STEVE: Landing on Mars, there really is nothing you can do.

You know, they call it the control room

but the one thing we don't have is any control.

NARRATOR: The EDL team was about to find out

whether the system that worked on Earth would work on Mars.

ADAM: You can't fully test the landing system here on Earth.

It's all been analysis, pen and paper, computer simulations.

Piece-part tests.

But you string it all together only once

in the skies above Mars.

STEVE: There were many things that could kill us in the process of landing.

A gust of wind at the wrong moment, a sharp pointy rock.

You can do everything right and Mars can still kill you.

MAN (over radio): ...entry. Five, four, three...

ADAM: And so as we go we're looking for certain signs from the spacecraft.

MAN (over radio): The vehicle has now hit the top of the Martian atmosphere.

We are now at an altitude of 73 miles

moving at a speed of 12,192 miles per hour.

STEVE: You're following what's happening.

You're hoping you got it all right.

You're hoping it's all gonna work.

MAN (over radio): Parachute deployed.

-(cheering) -(whooping)

ADAM: You get signals from the spacecraft

that it's executing all of its functions

all the way down to impacting the surface.

MAN (over radio): Signal indicates we are bouncing on the surface of Mars.

-(cheering) -This is a very good sign.

STEVE: We saw a radio signal.

The thing was bouncing on the surface.

MAN (over radio): Hang on, everybody, please be quiet.

We don't see a signal at the moment.

No signal at the moment.

STEVE: But then it went silent.

MAN (over radio): Please stand by, stand by.

STEVE: There was a significant stretch of time

in which there was no signal from the vehicle.

MAN (over radio): Deep Space Network tracking stations

are still searching for the primary signal.

STEVE: That was a very, very tense period.

ADAM: And we wait...

as if the spacecraft's dead.

And then we get the signal.

And the room erupts.

(cheering)

It actually worked.

(indistinct excited chatter)

NARRATOR: In a few hours pictures started coming down.

MAN (over radio): Oh, wow, look at that!

NARRATOR: Spirit was an international celebrity.

ROB: Ohh, yes!

NARRATOR: Opportunity would be arriving in three weeks.

And for a while, everything was perfect on Mars.

STEVE: Everything worked, everything worked.

All the hardware worked, all our operations processes worked.

The rover did what we asked it to do.

Everything's going great

and then 18 days into the mission it all just stopped.

CONTROLLER (over radio): I'm not seeing anything from our displays.

You're not seeing any signal at this time?

MAN (over radio): That's a negative.

CONTROLLER: Uh, copy that.

Let's look for it still.

STEVE: 18 days in, silence.

Nothing from the vehicle.

Not a clue about what had happened, just silence.

So we got a problem.

NARRATOR: Normally, Spirit would talk to JPL through the Deep Space Network,

once or twice a day.

Instructions went up from Earth,

and data came back from Mars,

until it stopped...

for two long days, and then...

ACE (over radio): Flight, station reported

that they're seeing signal at 1-4...

NARRATOR: A few garbled signals from Spirit.

The first clues to what might be going on.

STEVE: What became clear over a period of a day or two

was that for unknown reasons,

the computer onboard was crashing and rebooting

over and over and over and over again.

And it was doing it through the night.

Which means the computer is coming up

and it's sucking power out of the batteries.

At night you got no sun on the solar arrays

you're just pulling the battery down.

And you can only survive that for a few days

before the vehicle is done.

And so we were in a death spiral.

NARRATOR: Bad news was coming from all directions at JPL that night.

Spirit was not the only one in danger.

With Opportunity still a few days away,

the EDL team had been poring over data from Spirit's landing

to see if everything had gone according to plan.

ADAM: We saw something we didn't expect.

We saw something wrong.

NARRATOR: The lander had taken longer than expected to descend on its bridle.

Spirit got away with it, but Opportunity might not be as lucky.

WAYNE: This is obviously something that'll have to be investigated

to determine what has happened here.

ADAM: We were working literally full team, 24/7

doing tests in the vacuum chamber

trying to understand what had happened.

In the end we couldn't.

The buzzer went off and we ran out of time.

NARRATOR: All they could do was open the chute a bit earlier

to buy some extra time on the way down.

That would mean inflating it higher up, at higher velocity,

putting even more stress on the parachute.

STEVE: We're talking 48 hours before landing

about changing the parachute deployment parameters,

so we'll deploy high enough

that we won't smack into the ground too hard.

Um, that was a little nerve-wracking.

ROB: I have to admit, I did not sleep very well last night,

uh, because this is exactly what's going on in my mind,

you know, how can we have, what if we have two disasters on our hands?

I mean, all this, all this wonderful excitement

and suddenly we would lose everything.

NARRATOR: They uplinked new instructions to Opportunity,

now less than 24 hours away,

and hoped for the best.

TRACY (over radio): We're thinking there's a problem with the software.

NARRATOR: In mission control, they had finally detected a pattern

in the signals coming down from Spirit.

STEVE: The rover is sending us only real time data.

In other words, it's telling us this is what's happening to me now.

This is what's happening to me now.

This is what's happening to me now.

It's telling us nothing about what had happened before.

NARRATOR: A bug in the memory software

could be forcing Spirit into this endless cycle

of crashing and rebooting.

So they came up with a command that would bypass the memory altogether.

DIRECTOR (over radio): Flight, Mission, you're go.

CONTROLLER: Copy your go, Mission,

ACE you're clear to command.

ACE: Copy, Flight, radiation on my mark.

Three, two, one, mark.

STEVE: This was a guess.

This was an inspired guess and nothing more.

Maybe this will help.

CONTROLLER (over radio): Flight ACE, we have locked on telemetry, 1-4-5-4-1-4.

STEVE: And it worked.

MAN (off screen): Copy that.

(cheering)

(indistinct radio chatter)

JENNIFER: Like a well-oiled machine, isn't it? (laughs)

NARRATOR: With a software patch, Spirit would soon be back to normal.

MARK: We have partial control of the vehicle.

(laughing)

STEVE: We have got a way of talking to the vehicle now

so that it responds appropriately.

It has regained its sanity.

And that's a good feeling.

NARRATOR: Now it was Opportunity's moment of truth.

ADAM: We start clicking through the events,

touching the top of the atmosphere,

opening up our parachute...

(cheering)

...all the way down to the surface.

(indistinct radio chatter)

We don't hear from the spacecraft...

and then we do.

(cheering)

(indistinct radio chatter)

ADAM: To EDL!

(cheering)

I would like it very much much if we could go together,

to the press conference.

For Spirit the first landing

when the team had gone down to watch the press conference

we'd been barred because it was at full capacity.

This time I said, "No...

we're gonna go down together."

(cheering)

We got to the theater and there were security

and they said, "I'm sorry, can't let you in."

GUARD: You can't come in.

ADAM: I said, "I'm sorry," and we just walked in.

(cheering)

-(yelling indistinctly) -(whooping)

CROWD: EDL!

EDL! EDL! EDL!

EDL! EDL! EDL!

(whooping)

SEAN: To the Mars Exploration Rover team,

the best in the world, no doubt about it.

NARRATOR: Spirit and Opportunity were finally on Mars,

but now they had to produce.

The mission plan was for just 90 sols, 90 Martian days.

Dust on the solar panels was the biggest threat,

but there are many ways to die on Mars.

STEVE: You never know when these things are gonna drop dead.

You know, they could die tomorrow.

They could be dead right now

and we just haven't gotten the downlink that shows it yet.

Very nice from the looks of it.

NARRATOR: The rover teams at JPL approached

each sol as if it might be the last.

SCOTT: We were impressed very early with the idea

that the rovers were under a death sentence.

We knew that there was a kind of clock that was counting down,

and that at the end of 90 sols, like that was all the time

that we could count on that we were gonna get.

And we didn't even know if we'd get all that.

NARRATOR: The objective was to learn

whether Mars ever had the water necessary for life.

It's been a frozen desert for billions of years,

but the surface is scarred

with ancient river channels and deltas.

What was it like billions of years ago?

STEVE: How much water was there?

What was its chemistry?

Suppose you were a microbe, would you have liked that place or not?

If so, why?

NARRATOR: They sent Spirit to Gusev Crater

in the southern hemisphere

because it looked like a dried up lake bed,

and they hoped to find evidence in the rocks to prove it.

On the ground, though, there was nothing but volcanic rubble.

STEVE: I wouldn't have wanted to admit it at the time,

but the Spirit landing site initially was a crushing disappointment.

We went there looking for layered sedimentary rocks

laid down billions of years ago in a Martian lake

and instead we got lava as far as the eye could see.

And every damn rock was like every other damn rock.

They were just all the same.

And the thought was, "Well, we can go to an impact crater."

And the impact will have punched through the lava

and down into the good stuff that lies underneath.

And we spent 60 sols driving to an impact crater

and we look inside and it's full of lava.

HAP: We hoped for something a little more spectacular than this.

I'm gonna be surprised if we decide to drive down into the crater.

We might, but I don't know.

STEVE: It really was a bitter disappointment.

And, uh, the Spirit team got a little disheartened after a while.

NARRATOR: Opportunity got off to a better start,

touching down near the equator in a place called Meridiani Planum,

bouncing for a quarter mile,

and scoring an interplanetary hole-in-one.

At JPL they waited for the first pictures.

(cheering)

PETE: Look at this!

STEVE: We open our eyes and there's this astounding outcrop of layered bedrock

right in front of the vehicle.

That outcrop in the distance is just is out of this world.

I can't wait to get there.

(laughter)

It was like nothing anyone had ever seen.

Everybody had their idea of what Mars looked like,

and it's like, "What the hell is that?"

It was just alien.

This is an unusual Martian rock,

at least compared to what we've seen everywhere else.

The fact that these rocks are layered

says that one possible origin for these

is that they were laid down in liquid water.

We do not know what's going on here, but the beauty of it is,

we have preserved in front of us a record that will answer that,

and we have on our rover

a toolkit of gizmos that will tell us that answer.

NARRATOR: The rovers carry the toolkit of a high-tech field geologist.

There's a suite of instruments on the end of the arm

to identify rocks and minerals.

They see the world in three dimensions with four pairs of stereo cameras.

There's a high-resolution camera for color panoramas,

stitched together from individual frames.

Filters enhance details invisible to human eyes,

and a spectrometer scans for minerals that may have formed in water.

They have black and white stereovision for navigation and planning.

And below the deck, fisheye cameras see Mars at ground level,

looking backward and forward.

Opportunity headed for the outcrop, and soon made some startling discoveries.

STEVE: It was like being inside

this bizarre Martian mystery novel,

where every sol or two you get a new clue handed to you.

NARRATOR: First, tiny spheres the size of BB's,

littering the ground and embedded in the rock like blueberries in a muffin.

STEVE: It was such a surprise.

I mean, what the heck were those things?

NARRATOR: They turned out to be hematite,

the mineral seen from orbit that drew them here in the first place.

On Earth it forms spheres like these in water-soaked rocks.

Then they found sulfur-rich minerals that can only form in contact with water.

And finally, petrified ripples created by flowing water,

frozen in time as sand turned to stone.

It all pointed to a time billions of years ago

when water, actually, sulfuric acid,

soaked the ground and sometimes flowed across the surface.

STEVE: It was a new Mars.

There wasn't a single one of us who expected what we found.

Anybody who tells you so is lying.

Almost everything was a surprise.

We were giddy, we were incredulous.

We were sleep-deprived beyond words.

It was so tiring.

But we were just running on adrenaline.

And it was just so much fun.

It was the most fun I've ever had as a scientist, it was just fabulous.

NARRATOR: Opportunity's team declared victory

and moved on to a new target nearby,

while Spirit was still marooned in the wasteland of Gusev Crater.

STEVE: They were on different sides of the planet.

They were two very different sites

and they had two incredibly different experiences.

It was tough on the Spirit guys.

And for a long time the Opportunity team was the happy team

and the Spirit team was not so happy.

You know, I'd tell 'em, "Well, you switch to Opportunity."

And they'd say, "No, no, I'm not gonna."

Because they had gotten their heart set on Spirit succeeding.

SCOTT: Opportunity was certainly the lucky rover.

But for me I worked on Spirit, and Spirit is my favorite rover,

because Spirit had to work for everything she ever got in her life.

NARRATOR: Squyres knew that Spirit had to move,

and the hills on the horizon

looked like the only chance to salvage the mission.

STEVE: The Columbia Hills are two and a half kilometers away.

The vehicle was designed to go 600 meters over its lifetime.

Okay? That's four times the designed requirement.

That's a long, long distance.

We didn't know if the vehicle could do it.

NARRATOR: The engineers were skeptical.

ROB: I remember he said that. This is where we're going.

What do you mean, you're gonna drive up on those hills?

(scoffs) This is gonna be a lot more than 90 days.

Good luck.

We're probably gonna die on the way there.

He said, "No, we're gonna go."

I said, "Okay. You're driving. You've got the keys. Good luck."

STEVE: We're 100 sols into our 90-sol mission.

The warranty has expired.

Our only chance of getting to something new

was to push the vehicle

beyond anything it had ever been designed to handle.

Otherwise it was gonna be just lava until the end of the mission.

NARRATOR: While Spirit trekked to the Columbia Hills,

Opportunity faced a new challenge.

STEVE: Endurance Crater scared the hell out of me

the first time I saw it.

We pulled up to the lip of that thing, and there were vertical cliffs in places.

You know, it's the kinda place where if we screwed up,

you know a little rover could fall off a cliff and die.

NARRATOR: But the exposed bedrock down below was an irresistible target.

STEVE: Oh, my God!

It's like a whole new mission.

NARRATOR: Deeper rocks offer a chance to look farther back in Martian history.

STEVE: We didn't bring a drill rig to Mars,

but Mars has dug these wonderful holes for us

in the form of impact craters,

and they are our window into the subsurface.

We all wanted to go in.

I mean, we're standing on the lip of the most magnificent thing

anyone's ever seen on Mars,

with a rover that we all believe in our hearts can do it.

Everybody wanted to go into the crater, but you wanna do it right.

NARRATOR: Driving in was not the issue.

The question was whether Opportunity could get back out,

because the rovers were never expected climb.

ROB: We never had to test it to its limits before.

All we had to do was test to the requirements.

We had to convince our management here and at NASA headquarters

that we weren't gonna damage this vehicle or get stuck.

MATT: I mean, frankly, if we can't climb pretty reliably

up these rocks at 25 degrees,

we're not going into this crater.

STEVE: Everybody had to approve that decision.

If we did screw up, I didn't want somebody popping out of the woodwork

and saying, "Well, you didn't ask me!"

If you'd have asked me I would have said you can't go in!"

No, I wanted to make sure that we were all holding hands

when we jumped off the cliff together.

(indistinct chatter)

NARRATOR: First, they ran some tests.

STEVE: And in fact, the thing climbed beautifully.

I was stunned by how well this thing could climb steep, steep slopes,

as long as they were rocky.

30, 32 degrees, boop, boop, boop, right up it, it was amazing.

NARRATOR: In June, 2004, NASA gave the go-ahead

to enter Endurance Crater.

Opportunity's fate was now in the hands of the drivers,

the privileged few at JPL who operate the rovers,

translating directions from the scientists

into commands a robot can understand.

They spend their days immersed in a virtual Mars environment

created by the rovers' own cameras.

SCOTT (off screen): It's one of the just amazing things about this,

is the sense that you get of being there.

If you were standing at that spot on Mars right now,

this is what you would see.

STEVE: We built a vehicle that had intentionally human-like capabilities.

They're about the height of a person, they have 20/20 vision,

and you develop an almost tactile sense

of what it's like to touch Mars.

ROB: We are no longer working with a remote robot.

We are immersed inside it.

We find ourselves on Mars.

NARRATOR: It can take as long as 20 minutes

for radio signals from Earth to reach Mars,

so they can't be driven in real time.

CHRIS: You really are programming the rover.

It's not a joystick.

It's, okay, you know, go ten meters forward, turn five degrees,

uh, you know, check for obstacles, measure your progress.

NARRATOR: They don't know how the drive worked out

until pictures come back the next day.

STEVE: The rover's safety depends on those guys doing their job right.

Okay, the person who's running the Pancam camera

is not gonna drive the rover off the cliff or get it stuck in a sand dune.

That's the rover drivers.

JULIE: Nobody has more anxiety every day about what's being done to the rovers.

It's the feeling that I sequenced all the commands

that are gonna move this rover today,

and if something goes wrong, this is on me.

NARRATOR: Spirit had been slogging for eight weeks across a lava field

to the base of the Columbia Hills.

There might be a payoff on the upper slopes.

But getting there would be a monumental challenge.

Spirit's solar panels, her only source of power,

were getting dusty,

producing just half as much energy as they used to.

And she was about to face her first winter on Mars.

STEVE: We never expected to survive a winter, period.

We got to the base of the Columbia Hills 156 days

into what was supposed to be a 90-day mission.

The seasons were changing.

Spirit is in the southern hemisphere of Mars.

And what that means is in the winter

the sun is gonna go low in the northern sky.

And it's gonna get lower and lower and lower.

And as it gets lower the amount of power that we're gonna get from solar arrays

is gonna get less and less and less unless we can do something.

NARRATOR: It would help if they could tilt the solar panels

toward the sun to get more power.

STEVE: Well, we didn't build a tilt mechanism into the rover.

The only way to tilt them towards the sun

is to tilt the whole rover towards the sun.

But the beauty of it was, now we had a hill.

NARRATOR: If they followed a route

that kept the panels tilted toward the sun,

Spirit might be able to survive the winter

and climb the mountain at the same time.

They'd have to stay the course for at least seven months.

Mars takes two Earth years to orbit the sun,

so Martian winters are twice as long.

But now they had a chance.

STEVE: It started to dawn on us

that we maybe had more life in this thing than we had thought.

NARRATOR: Opportunity spent her first Martian winter

on a sunny slope inside Endurance Crater.

Sampling rocks down the crater wall added greater depth of time

to the water story at Meridiani.

Salty, acidic water soaked the ground

for hundreds of thousands if not millions of years.

When summer returned it was time to move on to something new,

but it was a long way from Endurance Crater

to anything much different.

The most obvious target was six kilometers,

almost four miles to the south,

a huge impact crater called Victoria.

Deeper than Endurance,

it was a chance to look even farther back in time.

JOHN: We thought, "Wow, could we get there?"

Six kilometers to the south, remember, that's six times

the designed distance capability of the rover.

NARRATOR: It looked like easy driving though,

so they decided to put the pedal down

and head to Victoria Crater.

Spirit had been climbing the Columbia Hills for six months,

surviving that first winter with solar panels tilted toward the sun.

By now though, they were so dusty

she would soon be unable to store enough power

to survive the frigid Martian nights.

STEVE: The power went down and down and down.

And Spirit was arguably getting close to the end.

And then one wonderful day a gust of wind hit the vehicle,

cleaned the dust off the solar arrays

and all of a sudden we had a brand-new rover again.

It was just pure dumb luck.

NARRATOR: Spirit sent back this picture of her own deck

just before the cleanup,

and this one just after.

STEVE: It's a new lease on life.

We've got more power than we can use.

I mean, we have to shut the vehicle down during the afternoon

to keep it from overheating.

It's producing so much power.

It was, it was just astonishing.

We were waking up the vehicle at night

and taking pictures of the stars, the moons of Mars.

I mean, we did amazing things.

We're stargazing.

We're explorers on another world

looking up and looking at the stars at night.

It added a whole new dimension to our experience.

It gave us a sense of what it's like at night on Mars.

NARRATOR: With power to spare Spirit now had a shot

at reaching the summit called Husband Hill.

SCOTT: Everybody who worked on Spirit wanted that accomplishment.

It wasn't so much about finding the liquid water anymore,

now it was about climbing that hill.

NARRATOR: Spirit had become a mountain climber,

and this was a chance to do something no climber had ever done before.

Spirit could claim the first ascent of a peak on another planet.

While Spirit climbed, Opportunity ran into trouble

on what was supposed to be an easy drive to Victoria Crater.

JOHN: It was just these gentle sloping dunes,

uh, literally all the way to the horizon.

There wasn't a rock or a hazard to be seen anywhere.

And we figured, "Oh, gosh, you could drive blind in this area," it was so safe.

STEVE: We were using a driving technique that I think could be charitably described

as bombing along at top speed with our eyes closed.

MAN (over radio): Flight, Mobility.

WOMAN: Go ahead, Mobility.

MAN (over radio): Up on screen number three

is the trajectory that the rover believes that it drove.

NARRATOR: On sol 446, things suddenly came to a halt.

Pictures from the previous sol popped up in mission control,

and Opportunity's wheels were buried to the hubs in deep sand.

STEVE: The wheels broke through the surface

and we did 50 meters worth of wheel turns,

thinking we were happily progressing across the Meridiani Planum surface,

and instead we were just digging slowly down and down

into this, into the sand.

MAIMONE: The wheels look like they're about 80 percent

under the ground there.

NARRATOR: It was a potential death trap,

and it took some time to figure out what to do next.

STEVE: The first rule in a situation like that is don't do anything dumb.

MAIMONE: It literally didn't make much more progress

after about this point.

STEVE: We shouldn't have gotten into this mess in the first place,

but let's not make it worse by-by guessing how to get out of it.

MAN: ...a roofline, we're putting obstacles.

NARRATOR: At JPL they built a Martian sand dune

trying different recipes of powdery clay and sand

to get the right consistency.

Then they brought in the test rover and spent two weeks

trying to come up with an escape plan.

(indistinct)

STEVE: After two and a half weeks they found out the optimal technique

was to just put it in reverse and gun it.

Um, you know, there's-there's no place you go to look this stuff up.

You just try things until you find what works best.

NARRATOR: On a Mars rover, gunning it happens in slow motion.

STEVE: We had to do 192 meters worth of wheel turns on Mars

to get the vehicle to move one meter.

It took days and days and days.

You know, you'd do four meters, eight meters worth of turns

and you'd come in the next morning and it went that far.

NARRATOR: On sol 484

Opportunity finally broke free of the trap.

The ordeal in the dune they called Purgatory

was Opportunity's first brush with death.

It would not be the last.

NARRATOR: In September 2005, after more than a year of climbing,

Spirit reached the summit called Husband Hill.

SCOTT: She stands there at the top of that hill

that she's conquered now on another planet

and she looks at the whole world around her.

I love her for bringing us that.

STEVE: More than anything else I think I felt,

"Gosh, aren't we lucky to do what we do."

You know, we just climbed a mountain on Mars.

Damn.

NARRATOR: From the summit they chose the next target,

a low mesa called Home Plate with a solar friendly hillside

just beyond it for the next winter.

165 sols later Spirit had passed Home Plate,

and with winter closing in, was headed for McCool Hill.

STEVE: The way we had spent the last winter

was climbing the north facing slope of Husband Hill.

And so we figure we'll head for McCool Hill

and keep the solar rays tilted towards the sun

and pull the same trick that we pulled last winter.

What happened though was, the right front wheel quit.

The right front wheel just stopped turning.

That came at a really bad time because we were trying

to get onto the slopes of the McCool Hill

and without that wheel functioning properly we can't climb.

NARRATOR: At JPL, they experimented with 5-wheel driving.

They found it easier to drive backwards,

dragging the dead wheel.

But it tended to pull the rover off course,

complicating the drives.

CHRIS: Each day we only had an hour to an hour and a half of power

and we had to write these incredibly complicated sequences of,

you know, sometimes 400 commands just to try to drive five meters.

SCOTT: You know when you go to the grocery store

and you get the shopping cart with the one stuck wheel,

um, and you're trying to get that down the aisle?

Driving Spirit at this point is a lot like trying to do that,

only your shopping cart is 300 million miles away

and you have to drive it with a keyboard.

STEVE: We're learning to drive all over again.

The seasons are changing.

The power is getting less and less daily.

Everybody's starting to get nervous, and then we get stuck.

JOHN: We got into this, it was kinda like quicksand and we couldn't get out of it.

So we were thinking, "Oh, my God, are we gonna be stuck here

and is the rover gonna die here?"

SCOTT: We were really in a race against the clock

because we had something like three weeks

before Spirit just wasn't gonna have enough energy to survive the night.

And people were talking about her like she was the walking dead.

NARRATOR: Within a week they got Spirit out of the trap,

but by then it was too late to reach McCool Hill.

STEVE: Now at this point I'm starting to realize

that my dreams of operating this vehicle and keeping it moving

and doing new science and new places all winter long, that's dead.

You know, forget about this stuff hundreds of meters away.

We're never gonna make it.

What do we got that's next to us?

NARRATOR: They settled for a spot nearby

where they could get at least a minimal tilt toward the sun.

STEVE: And that was it.

And there we sat for seven months.

But we survived.

NARRATOR: With the return of summer, Spirit was moving again,

driving backwards, dragging the dead wheel,

leaving a trench behind.

STEVE: We're driving along one day, in this little valley,

we look at the pictures of the trench that were dug that day,

and there's this one spot where the soil is

practically as bright as white snow.

That got our attention.

It turns out this stuff is more than 90 percent pure silica.

Not quartz. It's not beach sand.

This is amorphous silica.

It's like opal.

All of a sudden we realize we've just come across something

completely new and different that we had never seen before.

NARRATOR: On Earth, this kind of silica

forms in hot springs or volcanic steam vents.

STEVE: And the thing that's cool about that

is that you can go to hydrothermal systems on Earth

and they're teeming with microbial life.

Now I don't know if there was microbial life here.

We didn't, you know, bring fossil detection instruments with us,

but this is the kind of environment

that-that could have been quite appropriate

for some hardy types of microbes.

And that makes it a pretty important place.

NARRATOR: 1,200 days into her 90-day mission,

Spirit made her biggest discovery

and chances are, it would not have happened without the broken wheel.

In September 2006,

after almost two years on the plains of Meridiani,

Opportunity reached the rim of Victoria Crater.

The bowl is a half-mile across,

five times the size of Endurance.

STEVE: The view when we first pulled up to the rim,

it was just like nothing we had ever seen before.

It was like coming onto the Grand Canyon.

You know it's there but it doesn't really prepare you

for the enormity of what you're about to see.

NARRATOR: Millions of years of Martian history

could be exposed in these rock faces,

but to read it, they needed to get close.

Opportunity set off on a scouting mission that would last almost a year,

a daring drive along the sheer edge of the crater wall.

STEVE: So we're literally tip-toeing a hundreds of millions of dollar vehicle

along the top of a cliff on another planet.

If you can drive right out to the tip of one of those promontories,

right to the edge, you can shoot across with your camera

at the next promontory over,

which might be only 30, 40, 50 meters away,

and you'll see this wonderful cliff exposed there.

But in order to get that view you've got to go right to the edge.

SCOTT: We're right there on the edge of the cliff.

And this is what'll happens if we're not careful with the rover,

and our job is to not do that

and make sure that we stay up on this side of the cliff.

(indistinct)

NARRATOR: Along the way, the Mars Reconnaissance Orbiter

took a picture from 200 miles up,

showing the tracks of Opportunity's daring drive.

STEVE: To me that image represents one of the finest accomplishments

in the history of planetary robotics.

To have been able to pull off that drive,

time after time with the scientists saying,

"Oh, get closer, get closer, we gotta get closer!"

It was an incredible, incredible drive.

NARRATOR: After seven months, they'd seen enough from the rim

and were ready to go inside.

The best way in appeared to be the spot where they first approached the crater.

So Opportunity headed back where she came from 200 sols before,

and into the path of a dangerous storm.

NARRATOR: Weather is not usually a problem on Mars,

with one large exception.

Once every three years or so, there's a massive dust storm.

STEVE: Our first summer on Mars it didn't happen.

And our second summer on Mars it didn't happen.

But our third summer on Mars it happened.

And it blew up into a global storm,

blanketed the entire planet.

From where Opportunity sat on Meridiani Planum,

you looked up and you couldn't tell where the sun was in the sky.

The amount of direct sunlight

that was reaching the solar panels was less than one percent

of what it is on a clear day.

NARRATOR: At JPL they shut down all but the most essential systems

on the rover to conserve power.

JOHN: They were never designed to survive a dust storm.

The rovers are solar powered.

They need the sunlight to survive.

So each day we would turn things off reducing the amount of power.

But, you know, you can't turn everything off

because it's all about keeping the rover warm.

STEVE: One of the things that keeps the vehicle warm

is running the computer inside.

And so there was this delicate balancing act

between running the computer enough to keep it warm,

but not running it so much that you draw the batteries down too much.

And we were just right on the edge

of-of-of, uh, catastrophe.

NARRATOR: On the other side of Mars the dust was not as heavy,

and for once, Spirit had fewer problems.

But at Victoria Crater,

Opportunity was in serious trouble.

Soon the power would be so low

that the rover would automatically shut down

until there was enough sunlight to recharge the batteries.

Within a few days, that could be fatal.

JAKE: It's like sitting at someone's deathbed, you know,

and waiting and waiting and wondering,

"Well, is it going to, uh, gonna survive, is it going to come back?

Is it going to be able to talk to us or..."

And, uh, it-it was very agonizing, it got to the point

where you couldn't even take measurements to figure out how bad it was.

All you could do is just sort of sit there.

We just ran out of things to try.

NARRATOR: Just about everyone had given up hope,

but then the sky began to clear,

and the six-week ordeal finally came to an end.

Still the lucky rover,

a gust of wind cleared Opportunity's solar panels,

and she went back to work.

In Gusev Crater, Spirit survived the storm,

but when the dust settled, she got buried,

and winter was coming once again.

STEVE: We needed to find a place

for Spirit to try to survive its third winter on Mars.

And at this point the rover is so dirty from the dust storm

that a 12 degree tilt is not gonna cut it.

We need a 30 degree slope.

And this is a rover that can't climb 30 degree slopes.

NARRATOR: The only option at this point

was to drive across Home Plate to the north rim

where Spirit could back off the edge

to tilt her solar panels toward the sun.

ASHLEY: We had about 40 days to get there,

and of course with the power situation already getting low

we couldn't drive everyday,

and with that broken wheel

we couldn't get far on every day of those drives.

So we really had to make the most of that time.

So we started driving across the top of Home Plate

to get to this parking spot.

And we drove right into a sand trap.

NARRATOR: They call it Tartarus, the lowest level of Hell,

a micro-crater full of sand too deep for Spirit to handle with five wheels.

STEVE: We really got into a fix there.

The two back wheels were off the ground.

So they're not working at all.

The right front wheel is dead.

So a six wheel vehicle now actually only has three wheels

that are doing us any good whatsoever.

NARRATOR: There was one last escape route to try,

but it was right at the edge of Home Plate.

The slightest miscalculation on the way out

could send Spirit over the edge.

STEVE: We had tried every single trick we had.

And if that drive didn't work the mission was probably over.

ASHLEY: We sequenced it and we sent it up to the rover.

And a lot of us got no sleep that night.

STEVE: Sol 1388, I will always remember it.

That was maybe the most crucial drive that Spirit ever did.

And it worked.

We got out of Tartarus, and we got across Home Plate,

eased our way down onto that 30 degree slope,

and because of that, we have a fighting chance

of actually making it through our third winter on Mars.

ASHLEY: These rovers are pretty old now.

They're getting kind of arthritic.

They don't see quite as well anymore

because the cameras are getting more and more coated with dust,

so that their vision is getting a little fuzzy.

STEVE: They've been through so much.

You know, I mean, the perils that they have been through

and that we've kind of suffered through with them,

it's like any kind of relationship with somebody.

As you go through many things over the years,

the-the relationship deepens.

SCOTT: We feel so close to these vehicles.

They are our bodies, they are the way that we go to Mars,

and we're people who grew up dreaming about the possibility

that one day we might walk on other worlds.

STEVE: We can see ourselves in the rovers.

They've lasted so long,

it gives you a sense that they're... determined.

Determination in a, in a hunk of metal, but that's the way it feels.

And then above all they move through the scene

with the ability to do what a human would do.

To stop, look around, say,

"That looks interesting. Let's go there."

NARRATOR: In September 2008, after 700 sols at Victoria Crater,

Opportunity embarked on what looked like an impossible journey,

seven miles across the plains

to an even bigger crater called Endeavour.

STEVE: It looked crazy. But what were we gonna do?

We finished up at Victoria Crater.

We come out and for miles in every direction

it's more of the same stuff.

Endeavour Crater looked impossibly far away.

But it was the only goal that I felt was worthy of that rover.

And so we set off.

NARRATOR: Straddling Home Plate, tilted toward the sun,

Spirit survived her third winter on Mars.

Still coated with dust,

her solar panels produced a fraction of the power they once did,

but it was time to move.

Spirit was on the north side of Home Plate.

The scientists wanted to explore the area to the south.

The problem for the rover drivers

was how to get where the scientists wanted to go.

The shortest route was straight across Home Plate.

But with her broken wheel, Spirit couldn't climb back up the bank.

They tried the east side,

but ran into soft ground and had to turn back.

They had to settle for the long way around,

through unknown terrain.

On sol 1886, they were driving south along the west side of Home Plate.

It looked like solid ground,

but it was just a thin crust that suddenly gave way.

ASHLEY: And the wheels started spinning

in this very fluffy soft stuff

and we just couldn't get any traction.

SCOTT: We were driving a wounded vehicle through very treacherous terrain,

and, uh, we knew it.

This was the kind of trap that we knew might be out there waiting for us.

That's why we didn't wanna go down there in the first place.

But it was the only way to get where we wanted to go.

STEVE: Each time we would get stuck there was always a concern,

"Hey, this could be it."

But, uh, this one was looking worse than most.

JOHN: Well, there is a lot of stress.

People are having a hard time, we-we all are.

If there's a way of getting the rover out we're gonna find it.

It is however a very, very difficult situation.

NARRATOR: Months later, Spirit was still stuck.

Another winter was closing in,

and the rover was in a dangerous position,

with solar panels tilted away from the sun.

ASHLEY: We were running out of time,

after all of our testing we came up with a plan that we thought would work

and we were ready to try it out on Mars.

STEVE: But then, what sealed the deal,

what finished it was we lost another wheel.

The right front wheel had already failed,

and with two dead wheels that thing's not gonna move.

That was it. I mean, when we lost the second wheel we were done.

NARRATOR: In March 2010, Spirit did not call home

for a scheduled communication session.

Starved for power, the rover likely went into hibernation mode,

no survival heaters, no communication,

just waiting for the summer sun to recharge its batteries.

SCOTT: Even then, we still had a lot of hope for her,

and we still believed that she was gonna come out of it.

NARRATOR: By September 2010, spring had returned to Gusev Crater,

and with it, the possibility that Spirit would wake up and call home.

JOHN: We're involved in a very extensive recovery effort

sending commands to the rover in the hope of eliciting some sort of response.

NARRATOR: They sent up more than 1,000 commands

over the next ten months.

BEN: The command is radiating.

It will take four-and-a-half minutes, and then once that's done...

NARRATOR: They monitored Spirit's channels

on the Deep Space Network,

listening for any hint of a signal.

MAN (over radio): There's a possible signal we're trying to acquire.

BEN: Copy that.

NARRATOR: At times, they thought they had something.

BEN: Hey, John, 2-2-0-2-1-2 positive signal...

ASHLEY: Spirit had pulled things out of the fire so many times,

I don't think anybody truly believed that she wouldn't get out of this one too.

NARRATOR: Not this time.

By the spring of 2011, Spirit had been silent for over a year.

SCOTT: I've been missing her for a long time,

and it's tough to kind of put a finality to that, and say,

"Okay, that last time you heard from her

is the last time you are ever gonna hear from her."

JOHN: People are holding out hope but I think the reality is,

is people have to start to accept that, uh,

that Spirit's time on Mars may be done.

NARRATOR: They listened intermittently for another six months,

but Spirit's mission was over.

Her final resting place next to Home Plate

is a hard-fought five miles

from her landing site on the far side of the Columbia Hills.

STEVE: I always felt that the one honorable way

to lose our rover would be we just wore it out.

And that's what happened with Spirit.

We just beat it up to the point where it couldn't work anymore.

Which meant that we had squeezed everything out of our creation

that we possibly could have.

So that's an honorable death.

And then the other thing that made it tolerable

was we had to go back to work

and keep operating Opportunity the next day.

We still had a living rover.

NARRATOR: Spirit's mission was over,

but Opportunity was still crawling across the plains of Meridiani.

In early 2011 she was spotted at the rim of a small crater called Santa Maria,

seventeen miles from her original landing site,

with miles to go in her three-year journey to Endeavour Crater.

STEVE: It was a long three years,

day after day after day after day.

The only thing to break the monotony was an occasional meteorite.

ROB: I think some of the most haunting images from the rovers

has got to be Opportunity's look backwards

toward the place we had come from.

There's this sense of vastness of Mars,

the sense of being a long way from home.

This poor rover is so far from where it had come,

and yet had so far to go to its next destination.

NARRATOR: Like a captain's log,

Opportunity's camera recorded the long voyage to Endeavour Crater.

STEVE: It was very reminiscent

of what you might imagine if there's a sailor,

a sailing ship that's been at sea for a long period of time,

and we were driving across this flat ocean,

and off in the distance rising like an island

out of that ocean you can see the rim of Endeavour Crater.

It got closer and closer and closer every day.

And it felt like coming ashore.

And when we got to the rim of the crater everything changed.

It was like a new landing site. It was like a new mission.

It was a breakthrough for us.

It was really a breakthrough.

Now we're seeing completely different geochemistry,

completely different geology.

The most exciting thing was that we found

very, very concentrated deposits of clay minerals.

And clays tell a story about water completely different

from the one that we had seen before.

The clays tell a story about water you could drink.

Water that's neutral in its pH.

Water that would be much more suitable

for, uh, not just the existence of life

but for the birth of life.

NARRATOR: Opportunity would spend the next seven years

exploring the rim of Endeavour Crater.

In February 2018, she passed 5,000 sols on Mars.

JOHN: This is like a car going a million miles without an oil change.

I mean, it's just phenomenal.

And we still don't understand how it was able to last so long.

NARRATOR: In June, Opportunity was headed down

a valley in the crater wall

when a massive dust storm rolled in,

far worse than the one she survived 11 years before.

JOHN: It was just a completely dark sky,

uh, no sunlight and so no power generation

and eventually the rover would exhaust its batteries and fall silent.

NARRATOR: Unpowered and unheated at 100 degrees below zero,

a younger rover might survive,

but Opportunity is no longer young.

JOHN: This is like the difference between your teenage nephew

going out in the winter time without a jacket

and your 97-year-old grandmother

going out in the winter time without a jacket.

The teenager you're not so worried about,

but your grandmother you're really concerned about.

And so that's where we are.

NARRATOR: Three months later the storm begins to clear.

If Opportunity survived, and the sun is recharging the batteries,

the rover should wake up and call home.

(inaudible)

But there may be so much dust on the solar panels

that Opportunity would shut down again before making the call.

JOHN: It's an unlikely scenario but we wanna cover all possibilities

so we're sending commands,

hoping to catch the rover when it wakes up briefly

before it shuts down again.

And these commands would tell the rover send us a signal.

(inaudible)

JOHN: So this is a wide band receiver,

that's just listening for anything that might be coming down,

and what we would expect to see

would be a sharp spike right here in the middle,

a sharp line which would be our rover talking to us.

NARRATOR: The panels may be so dirty

that Opportunity can't wake up even briefly.

But that could change in the months ahead when the windy season returns to Mars.

ASHLEY: You know, if she's really dirty, we know the winds are coming

and we've seen the rovers get cleaned off every year

and it could well be enough that, to-to wake Opportunity back up again.

But it is Mars, so we don't know for sure,

we'll just have to wait and see.

JOHN (off screen): This is done.

Uh, no signal, that's a wrap for today.

We'll try again tomorrow.

NARRATOR: They set out to prove that Mars is worth exploring, despite the risk.

ADAM: Spirit and Opportunity changed the way we think about Mars.

When your perspective is constantly changing,

you are exploring as a human being would explore.

And this was our first view of what that looks like.

And the discoveries that water had been on the surface

meant we were going back.

We have put other missions on the surface of Mars

and we are working on putting

additional missions on the surface of Mars.

And we're really doing all of that because of Spirit and Opportunity.

NARRATOR: Eight months after falling silent,

there was still no sign that Opportunity survived the storm.

In February 2019,

just over 15 years since Opportunity landed on Mars,

NASA announced that her mission was over.

Spirit and Opportunity opened the Martian frontier for good,

and now they'll sit forever on a planet

where little has changed in billions of years.

STEVE: It's cold, it's dry, there's no vegetation.

They're not gonna rust or anything like that.

You know, these things could be still sitting there

with their, you know, aluminum surfaces shining a million years from now.

They're gonna last a long, long time.

Longer than most things that humans have ever built.

Captioned by Point.360