(narrator) Space exploration began with dreaming,
thousands of years of humans staring into the heavens
and wondering, "How did this begin?"
"What else is out there?"
The earliest answers were given in myth and poetry.
Now they are sought by space-age technology,
and while each mission increases our knowledge,
it also leads our imagination further and further.
How did life begin?
Did it happen more than once in the universe?
The answer may lie on Mars.
Mars today is desolate, dry and barren,
and at first glance has little in common with our own planet,
and yet from orbit we see what look like dried-up lake beds and canyons -
clues that, three or four billion years ago,
Mars may once have been wetter and more Earth-like.
And since life blossomed here on Earth, the question is,
did it ever take place on Mars?
To answer this question, NASA's Jet Propulsion Laboratory
brought together a team of scientists and engineers
whose mission was to discover if Mars ever had what was needed to support life.
A geologist and astronomer at Cornell University,
Steve Squyres was chosen to lead the science team.
As principal investigator, he would direct the team's search
for life's most essential resource - water.
(Squyres) I've worked on the question of water on Mars for 28 years.
You can't learn what you need from a telescope. You must be a geologist.
A geologist is sort of like a detective at the scene of a crime.
Something happened here a long time ago. What happened?
Was it warm? Was it wet? Could life have existed here?
The key is in the clues, and the clues are in the rocks.
On Earth, a geologist can find an interesting rock,
crack it open with a hammer and look at what's inside.
But we're not ready to send a human geologist to Mars yet.
So we had to build a robot geologist,
and the only place this could be done was NASA's Jet Propulsion Laboratory,
where some of the most innovative engineers in the country work.
We're talking about a robot, a rover that can go to Mars,
land on the surface, take a look around and then cut the cord and go -
carrying everything it needs with it -
cameras, instruments, communications equipment, everything.
Something that can look inside rocks and can tell us what clues those rocks hold.
This place to me is almost sacred.
This is the place where our rovers are assembled before they leave this planet.
Everything that we do in this room must be perfect.
Over 4,000 people have worked on this mission.
For every single piece of this spacecraft, down to the tiniest one,
there was a person somewhere who conceived it, who nurtured it,
who took it from a concept to something real.
It's taken this team three years to design and build and test these rovers,
and we still have work to do.
We can only launch when the two planets are properly aligned,
and that's just a month away, but we still have tests to run.
We're working in shifts, around the clock, and we don't know if we're gonna make it.
(man) There's no one who can get their arms around this thing and say:
"I understand everything about this vehicle."
It's now burst the bounds of our brains.
This rover is more than just a roving geologist.
This rover also has to be a spacecraft.
It actually has to fly itself from Earth to Mars.
In addition, it has to do the very subtle and quick timing control
of all the things that happen as it enters and lands the vehicle.
We had to stuff all that intelligence and capability
into that little six-wheel vehicle back there so that it could get there safely on its own.
I call our spacecraft the "origami spacecraft,"
which means it's really a complicated series of folds.
We punched holes in the lander petals for the wheels to stick through.
We've had to fold everything into these complicated shapes
to get this system to fit inside this tetrahedron.
It's beautiful, but at a price, and that price, in this case, is complexity.
(Squyres) There have been missions to Mars since the '60s, dozens of them,
but two-thirds of those missions failed.
Mars is a spacecraft graveyard.
A spacecraft has to travel about 300 million miles to get to Mars
at about 60,000 miles an hour,
but it still takes seven months to get there.
Trying to hit our landing sites from that distance
is like shooting a basketball from Los Angeles to New York
and having it go through the hoop without touching the rim.
The smallest mistake on our part could put the whole mission in jeopardy.
Two of the last three missions to Mars were failures.
One spacecraft burned in the atmosphere, the other one crashed on the surface.
This time, NASA decided to send two identical spacecraft
to double our chances of success.
The two rovers are named Spirit and Opportunity.
They have different personalities.
They did when they were babies, back when we were first building them.
Spirit was our troublesome firstborn.
Every test we ran, we ran on Spirit first,
and the first time you try, it usually doesn't work.
We'd run tests on Spirit and they'd fail.
We'd try to fix things, run another test, and that would fail, too.
By the time we got to Opportunity, we'd learned stuff,
and things went much more smoothly.
The biggest problem was underestimating the size and weight of the rovers.
Once we realized how big they really had to be,
we also realized that the landing system we planned to use
couldn't get them to the ground in one piece.
As the rover got heavier, the lander got heavier, the aeroshell got heavier.
The whole thing got heavier and heavier.
From the very beginning, on this mission, it seemed like nothing was going right.
(Squyres) The air bags are like the air bags in your car, but way more expensive.
They inflate explosively around the vehicle and they cushion the landing.
The first time we tested them, they tore open and deflated.
Setbacks are going to happen.
I always tell people, when you start these projects,
the same thing probably happened to Lewis and Clark
and Captain Cook in their exploration -
what is guaranteed is there will be setbacks.
(man over radio) Three, two, one...
(Squyres) These rovers have to land using a supersonic parachute.
The parachute design we thought would work ripped to shreds.
The lander had gotten so heavy that the chute just couldn't handle it.
We were almost out of time, and all we had was a chute design
that would destroy the spacecraft when we tried to land.
(Manning) We had to build a whole other set of new designs -
no less than three or four designs we had to test
in the three months that followed in our mad rush to make it to the launch pad.
We were running out of money, we were running out of time.
Uh, well... I mean, the drop was successful.
The fact that the parachute exploded - not a good thing.
- I'd rather have it happen here than... - Mars. That's right.
Unfortunately, strictly speaking,
that chute that just exploded was the chute that we were planning on taking to Mars.
(Squyres) Mars is a tough place to send a spacecraft.
The average temperature is 60 degrees below zero.
It goes down to 100 below zero at night.
There can be dust storms that darken the skies for months at a time.
But if the rovers make it, they'll give us the experience
of what it would be like to be on Mars.
We'll be able to look into the distance and say, "Yeah, I'd like to go there,"
and then actually go and see what we find.
The rover's arm has the dimensions of a human arm,
with a shoulder, an elbow and a wrist.
The arm tucks up tight under the front of the vehicle for when we drive around,
but when we get to a rock that we want to examine,
the arm unstows and reaches out, using all of its joints
to place the instruments on a rock and to begin to study them.
The hand has four fingers. One is a microscope,
two are spectrometers to tell us in detail what the rocks are made of,
and the fourth one is called the RAT - the Rock Abrasion Tool.
To examine the rocks, we've got to get to them, and Mars is very bumpy.
To deal with bumps, engineers came up with a "rocker-bogie" suspension system.
It's a very clever design that allows each of the six wheels
to go up and over a rock independently while the rover itself hardly tilts at all.
OK, come on in, guys. Now, stay clear. Watch it, watch it.
Stay clear of this. It's gonna move. Watch the wheels...
(Squyres) It goes way beyond this single mission.
The eventual goal is to send humans to Mars,
but the first person to walk on Mars is not an astronaut today.
It's someone in high school or in elementary school.
(man) So it's turning in place, then, when it gets lined up,
we're gonna drive it backwards.
(Squyres) We've invested so much work, so many years,
so much of our hopes and our dreams into these rovers.
And then when you think about where they're going,
the ride they're gonna get on that rocket, the transit through space,
what it's like when that parachute goes out,
going through the Martian atmosphere.
You're standing next to this robot
and you realize it's gonna spend eternity on the surface of another world.
It's going to another planet, for real.
And once they're gone, that's it.
After the rovers launch, we're never gonna see them again with our own eyes.
We've done everything we can to prepare them for the dangers they'll have to face,
but it's gonna be very hard to say goodbye.
(wind machine)
Spirit will be launched first, then Opportunity three weeks later.
Mars and Earth are both orbiting the sun,
so they're always moving relative to each other.
Every 26 months, there's a brief interval when the planets are lined up just right.
At that time, and only at that time, we have enough rocket fuel to make it.
So this is our one shot.
(man over PA) 5,4,3,2,1...
(Squyres) We don't fire a rocket motor all the way to Mars. We don't need to.
We just place the spacecraft on a trajectory to Mars,
and let it coast for 7 months and 300 million miles
until it reaches the planet.
Once it's been pushed on its way to Mars by the launch vehicle,
it has to maintain its orientation toward the sun
and it needs to be able to correct its orientation and direction
so that it would hit Mars and get to this tiny spot on Mars we're aiming for.
So all that has to take place over the course of the seven-month journey.
(Squyres) Landing is when the real challenge begins.
Mars is so far away, it takes about ten minutes
for a radio signal to travel one way between Mars and Earth,
but it's only six minutes from when we hit the top of the Martian atmosphere
to when we're bouncing on the surface.
There's nothing we can do to help when it's time to land. The rovers are on their own.
We're passive, passionately interested observers
waiting for a radio signal that shows whether or not they've survived.
Not going to be an issue. The current reported temperature
is about zero degrees Celsius, which is close to the limit,
the flight-allowable limit...
(man) Landing on Mars is so complicated.
There are so many things that can go wrong.
The flight computer has to know precisely the right time to deploy the parachute.
If it deploys it too high, when the parachute opens,
the wind forces will just rip it to shreds.
If we deploy the parachute too low of an altitude,
it won't open in time, and we'll just crash right into the ground.
(Squyres) The trick is every time there's some critical event -
the parachute deploys, the heat shield falls away -
we change the frequency of the radio signal.
And so Polly's sitting at her console,
and she's looking for these changing frequencies.
And when the number changes, she knows that this event has happened,
that event has happened.
(radio) Flight Director Willis reports all systems are go for Entry Descent Landing.
We are roughly 11 minutes, 48 seconds from landing
at the Gusev Crater in the southern hemisphere of Mars.
Atmospheric entry in 3, 2, 1.
We have just passed one minute to atmospheric entry.
Current altitude 121 miles, current velocity 12,084 miles per hour.
We are now at an altitude of 73 miles,
moving at a speed of 12,192 miles per hour.
Expected parachute deploy in five seconds.
4, 3, 2, 1, mark.
We are awaiting confirmation that parachute has deployed.
(man) Parachute's been detected.
Heat shield deployed event.
Spacecraft reporting that heat shield has jettisoned.
- Separation detected. - Spacecraft reports lander separated,
moving at a speed of 173 miles per hour. We are near our terminal velocity.
Expected retro-rocket ignition on my mark. Mark.
At this point in time we should be on the ground.
Any signal that we receive from now indicates the vehicle would be alive,
on the ground and bouncing.
The spacecraft has to survive all the bounces for landing to be a success.
No signal at the moment.
(man) Stand by.
(Lee) Signal strength is currently intermittent.
- We don't see a signal at the moment. - Right.
We saw an intermittent signal that indicated we were bouncing.
However, we currently do not have signal from the spacecraft.
Please stand by.
We're approximately ten minutes after landing.
The vehicle should have rolled to a stop by now.
The stations in Goldstone and Canberra are searching for the signal.
(woman) We see it!
- (man) What do we see? - (man ♪2) We've got the signal!
(Squyres) The first thing to do is open our solar panels to the sun
so we'll have some power. This charges up the batteries.
After that, we can deploy the camera mast so the rover can see,
and deploy the antenna so the rover can talk to us.
(cheers and applause)
(man) Our first pictures from Mars!
- What is that? - That's looking down on our vehicle.
(woman) Oh!
We could not have imagined returns as early as this,
as clear as this, as successful as this,
and in the volume that it has been.
Ladies and gentlemen, Mars.
(Squyres) We sent Spirit to Gusev Crater,
a crater in the southern highlands of Mars.
It's 100 miles in diameter.
What makes it special is that emptying into it is a giant water-carved channel.
Gusev is a hole in the ground with a dry river flowing into it.
There has to have been a lake in this crater once upon a time.
We sent Spirit there to seek out sediments, to look for sedimentary rocks
that were laid down long ago in that lake.
Once we landed, the scariest part of the mission
was the initial unfolding of the rover.
There are so many gears and springs and motors and hinges and latches
that have to work just right, or you're done.
Once everything's deployed, we're ready to look around.
We can look into the distance with our cameras and our infrared spectrometer,
and we can learn a lot from a distance of 50 yards, 100 yards,
about what the rocks look like and what they're made of.
Then, if we see a rock that has a texture or a composition
that looks interesting to us, we can drive over to it and check it out in detail.
For driving, the rover has these kind of googly-eyed cameras
that it uses to take images of the terrain in front of it.
They've got wide-angle lenses, and they provide sort of a fisheye view.
Spirit uses these pictures to make its own decisions about how to drive.
It'll look at a rock and say, "That's too big. I have to go around that."
Or maybe it'll see smooth sailing and just move on.
We can actually program different levels of courage or cowardice into the rover,
telling it how aggressive to be, depending on how dangerous the terrain is.
The rovers are so complicated that it takes hours to get a set of commands right,
so when we operate them, we'll normally send commands to them just once a day.
The first rock that we looked at was this one.
We named it Adirondack.
When a rock sits on the surface of a planet,
it can undergo what's called "weathering."
When it's exposed to sunlight or humidity or wind,
the surface of the rock can be modified,
and the evidence of how it formed can be destroyed.
So, to get to the clues you need,
you have to get inside the rock, below the weathered surface.
The key to understanding Adirondack was the Rock Abrasion Tool.
The RAT gives us the ability to grind into a rock,
exposing the unaltered evidence inside.
So we put a RAT hole into Adirondack and then we hit it with everything we had.
We looked at it with our cameras, our spectrometers, and our microscope.
Adirondack is a piece of lava. It's not a sedimentary rock.
And every other rock around it is a piece of lava, too.
This was a huge disappointment.
We came to Gusev Crater looking for sediments
that were laid down long ago in a lake,
but what we found was lava - volcanic rock.
The sedimentary rock must be there, but it's been buried under the lava,
and we couldn't get to it.
When we realized that we hadn't landed on the stuff we came for,
we decided we had to go someplace else.
A mile and a half away, there's this spectacular range of hills
called the Columbia Hills.
Spirit was designed to go only 600 yards over its lifetime,
so we set out for those hills not knowing if we'd ever make it.
Meanwhile, on the other side of Mars, Opportunity was about to land.
When Opportunity landed at Eagle Crater,
it was a 300 million-mile interplanetary hole in one.
We rolled to a stop right in front of layered bedrock.
Bedrock is geologic truth.
Opportunity landed in front of a Martian history book.
When we drove off the lander and looked at the soil in front of us,
we saw that it was littered with what looked like little round beads,
an uncountable number of little round things.
We took out our microscope, we reached out and looked at the soil in detail,
and the picture that came down was astounding.
They were perfect spheres.
I will remember for the rest of my life
how I felt when I saw that first picture.
When we looked at the outcrop up close,
we realized that the spheres are embedded in the rock
like blueberries in a muffin.
The rock erodes away and the blueberries fall out and roll down into the soil.
The blueberries are made of hematite,
a mineral that on Earth is often formed in liquid water.
Next we found jarosite, which is a mineral that couldn't have formed
unless there'd been water in the rocks, so there was water underground here.
Our most extraordinary discovery came when we found ripples in the rocks,
ancient ripples formed when water flowed over sand on Mars billions of years ago.
So there wasn't just water underground here,
there was water at the surface.
Opportunity discovered that at this place billions of years ago,
Mars was most likely a habitable world.
A place that, for some interval of time, was suitable for some forms of life.
Decades of work paid off with this discovery.
Billions of years ago, there were shallow occasional pools of water.
Don't think an ocean. Think of salt flats.
And the water may not have been a pretty blue.
In fact, it may have been so acid, it dissolved iron out of the rocks
and made wine-red pools under a pink Martian sky.
All the discoveries that Opportunity made about water
happened in the first six weeks of the mission.
Everything went right for that rover.
I call Opportunity "Little Miss Perfect."
Opportunity lands where the evidence is right there.
The driving is like a parking lot. Everything is perfect.
Spirit, our kind of tough, hard-working, blue-collar rover,
lands in this awful, rocky, rugged place on a lava plain
a mile and a half from the nearest interesting rocks
and has to struggle for five months just to begin her mission.
Spirit had to work for everything, literally had to climb a mountain on Mars.
We use the power that comes from the sun
to operate the vehicle and to charge the batteries,
so the solar arrays are essential.
On the way to the Columbia Hills, Spirit's solar arrays got coated with dust.
We were getting to the point where Spirit was simply gonna die.
Then, one wonderful day, we climbed up onto the crest of a ridge,
where we were hit by not one but several gusts of wind
that just cleaned the solar arrays off.
It was like having a brand-new rover.
Spirit got high up in the Columbia Hills
and started to find stuff that was different from anything we'd seen.
There were salt deposits in the hills and rocks that had been altered by water.
It took months of work and struggle, but Spirit finally showed us
there had been water on both sides of the planet.
She gave us exactly what we needed.
These rovers were designed to last only 90 Mars days,
and they've already done many times that.
They've developed personalities. They're workhorses. They say:
"Push us. Ask us to do more. We can go further. We can go faster."
So we ask so much more than they were ever intended to,
and to our amazement, they do it.
We don't know what will kill these rovers. They do get old. Motors break.
Lubrication goes away in the motors, the wheels may stop turning.
We have no idea what will happen.
But they're not gonna last forever, and as the dust keeps falling,
the solar arrays keep getting dirty.
What could happen with time is someday we won't be able to charge the batteries
to keep the rover warm at night, and if that happens, it'll get too cold,
and one morning, it just won't wake up.
Spirit and Opportunity have shown us that once,
three to four billion years ago, Mars had the essential ingredients for life,
so the next step is to seek out evidence of life itself.
Right now we have one example of life - us.
We may be all there is. We simply don't know.
But if you can show that life developed twice in one solar system,
and then you consider the multitude of solar systems out there,
it takes no great leap of imagination to believe that life might be
a common phenomenon throughout the universe.
Our rovers have gone farther, harder and longer
than even we, their creators, believed possible.
They've done heroic work.
But someday we won't need robots.
Someday there'll be humans on the surface of Mars,
and boot prints in our wheel tracks.
This mission has put us on a great trajectory
to learn more about Mars and about ourselves.
But right now Spirit and Opportunity are still roving Mars.
It's not just that they've exceeded our wildest dreams -
in many ways they are our wildest dreams.