Original subtitles

MAN: T minus 40 seconds. Everything looks good for launch.

NARRATOR: Have you ever fantasized about going somewhere special?

Somewhere far from crowds, off the beaten track?

Somewhere out of this world?

Is it time to catch a rocket to the red planet?

MAN: Mars is filled with mysteries: volcanoes 75,000 feet tall,

huge canyons, 3,000 miles across and 6 miles deep,

all kinds of interesting features.

NARRATOR: Awaiting you is some of the greatest scenery

in our solar system,

on a world where water once ruled, then vanished into thin air.

Where lost microbe empires may still survive underground.

We've seen the postcards, and we do wish we were there.

MAN: Just the thought of being in this new world,

seeing a landscape that no other person had seen before,

| think there are a lot of astronauts that would sign up to that.

NARRATOR: But don't be fooled: nothing about going to Mars will be easy.

Danger awaits you on this desolate beauty,

and perhaps Martians, too.

MAN: If we find on Mars evidence of a second independent origin of life,

that's hugely profound because it tells us right away

that life is common in the universe.

NARRATOR: Mars.

Invaded by a robot and perhaps soon by an Earthling like you.

MAN: Would | like to go to Mars? Oh, in a heartbeat.

Absolutely.

If there was any way for me to be going to Mars

| wouldn't be screwing around with robots, you know, I'd want to go myself.

NARRATOR: There has never been a better time

to boldly go where no human has gone before:

to follow in the footsteps of our robot pioneers

and visit the planets of the solar system.

NEIL ARMSTRONG: That's one small step for man...

MAN: Oh, man, that's incredible!

NARRATOR: It's been said that the first person on Mars

is alive somewhere on Earth today.

Imagine it's you.

What do you need to know?

How might you get there and what should you pack?

What are some of the must-see sights

and what should you avoid?

Think of this as your personal travel guide to exploring the red planet.

Mars has always had a mystique.

It's one of the easier planets to spot in the night sky,

a constant dot of red light moving through the heavens.

And now we know for sure that of all the planets,

this red, rocky one is the most similar to home.

Here are polar caps and sun-baked deserts,

giant volcanoes and mighty canyons.

Mars even spins at about the same speed as Earth,

making a Martian day only about 40 minutes longer than ours.

Although it's further out from the sun and takes twice as long to circle it,

the long Martian year has identifiable seasons.

And what's more: our two planets share a common childhood.

LYNN ROTHSCHILD: In many ways it's a sister of the Earth.

It was formed at roughly the same time, about 4.5 billion years ago

with a little change here and there.

It also was formed of the same sorts of materials,

bombarded by comets and asteroids.

So it has the same delivery system we have.

NARRATOR: Could life have been forged in the same way on both planets?

When we sent the first probes to investigate in the 1960s,

almost anything was possible.

ROTHSCHILD: Originally in the popular imagination

we thought that Mars might be inhabited by whole civilizations,

building canals and so on.

And then the Mariner flyby missions

really painted a very grim black and white view of Mars as being barren.

ANNOUNCER: The pictures and data recorded by Mariner 4

revealed Mars to be a cold, barren planet.

MAN: We should be coming up on terminal descent ignition.

MAN: SCS is close to vertical.

NARRATOR: Still, NASA was eager to look for signs of life.

In 1976, the Viking spacecraft arrives from Earth for our first close encounter.

And there are still hopes of a welcoming committee.

But both Viking spacecraft send back photos

of nothing but rocks and sand.

BEN CLARK: We had cameras, so obviously if there was a yucca plant

or | was hoping there would be a freeway in the distance,

but what the main thrust of Viking was actually,

was some chemical laboratories

and they looked for the chemical signs of life.

NARRATOR: Even the dirt seems devoid of life.

ROTHSCHILD: There was always the chance

that when they were so busy looking for microbes

there could be a large organism looking over their shoulder

that they completely missed.

But now we have enormous amount of imagery

that shows nothing like a large organism.

There are no cats running around,

there are no bisons, there are no palm trees.

NARRATOR: It seems Mars is not the kind of planet

that gives up its secrets easily.

But if you dig a little deeper,

you soon find that this is a world worthy of a closer look.

There are some basic things you should know about Mars

before leaving home.

Most days will be clear and sunny and cold.

The average temperature on Mars is as bitter as mid-winter in Antarctica.

At about half the diameter of the Earth, Mars is a handy size.

But it's much less dense than Earth, with about a third the gravity.

Surprisingly, the actual surface area is almost exactly the same

as all the dry land on Earth shrunk together without the oceans.

Build a few freeways and you could drive around Mars in a couple of weeks.

And driving around Mars is exactly what planetary scientist Steve Squyres

has been doing since 2004.

Not in person, but via NASA's two off-road robot rovers,

Spirit and Opportunity.

[applause]

STEVE SQUYRES: It looks like nothing I've ever seen before in my life.

NARRATOR: For all of us here on Earth,

the snapshots sent back by these forward scouts

are the next best thing to standing on Mars in a spacesuit.

SQUYRES: We very consciously gave these robots some human-like qualities.

The cameras are about this high off the ground;

they are the same height as human eyes.

The visual experience that you get from looking at the rovers’ pictures

is intentionally like what you would get

if you were looking out the visor of your helmet and a spacesuit on Mars.

NARRATOR: In the four decades since our robots first arrived,

the once fuzzy ball at the end of our telescopes

has steadily focused into a red planet we can understand.

And it's not a welcoming place.

The problem is the atmosphere is so thin and cold

that water exists only as solid ice in the ground or vapor in the air,

not as a liquid on the surface.

You might see some fine, wispy clouds high in the sky,

but don't bother bringing an umbrella.

The whole planet is drier than the dustiest desert on Earth.

And there hasn't been a drop of rain here

for millions, perhaps billions, of years.

SQUYRES: The thing that fascinated me

was that we could see valleys snaking across the surface

that had clearly been carved by flowing water.

So this is telling us that in the past it was different

and not only that, it was different

in a way that would have made it more suitable for life than it is today,

and that I found truly compelling.

CLARK: We are very convinced that at one time

it was a very hospitable planet with liquid water

and enough atmosphere to sustain a climate,

and so now we're trying to understand how did it change,

why did it change and what still might be on Mars?

NARRATOR: These are deep Martian mysteries.

lf Mars and Earth started as sister planets,

did life once festoon the Martian surface?

Might it still be there?

And where did all the atmosphere and water go?

Solving these puzzles has challenged our planetary explorers

from the moment the first Martian postcards were sent back to Earth.

SQUYRES: It's the fact that it is so much like Earth

that kind of makes Mars such a special place.

NARRATOR: Steve Squyres' Martian odyssey

has taken him from pole to pole--

visiting those places on Earth

that share at least some of the same characteristics:

they are extremely dry, extremely cold,

or extremely dead:

Death Valley is one of his favorites.

SQUYRES: This is actually a really important place.

It's a place we call Mars Hill.

We first found this place about 20 years ago.

In those days the only successful landings that had taken place on Mars

were the two Viking landers,

and they landed in places that looked very much like this.

NARRATOR: In order to plan for the current Mars mission

and to test the cameras and other equipment,

NASA needed a good Mars look-alike.

They found it at Mars Hill.

SQUYRES: To your eyes

the main way in which Mars would look different from this scene

would be the color.

The color of the sky and the color of the rocks

and the color of the soil.

The colors on Mars are painted from a very narrow palette.

NARRATOR: The color palette here is based on rust.

Rich in iron oxides, the rocks and soil and the rusty dust

are always blowing around in the freeze-dried atmosphere.

You won't see any blue skies in the tourist brochures for Mars.

Instead, they're amber.

Not only do the dust particles add a rosy blush to the sky,

they also scatter sunlight

in a way that turns the color of the Martian sky

upside down to human eyes:

red by day and blue at dawn and dusk.

This is a sunset as seen by Spirit:

a cold blue sun dropping over a distant alien horizon.

Looking up into the clear, starry skies from the surface,

you would see Mars' two tiny moons:

Phobos and the smaller Deimos.

With all the grace of a space potato and barely 17 miles long,

Phobos has been targeted as a potential stepping stone

for the first human mission to Mars.

A test run, before attempting the fuel-hungry and risky trip to the planet below.

RICH ZUREK: To put humans on the surface of Mars,

someone once joked there are only three issues--

getting them there, keeping them alive while they're there

and getting them back.

NARRATOR: Our Space Age dreams of off-world colonies on the moon and Mars

faded with the cancellation of the Apollo program

and the last trip to the lunar surface in 1972.

It didn't stop us from traveling.

We simply switched from astronauts to lower cost, lower risk robotic explorers.

And when it comes to Mars, it's probably just as well.

SQUYRES: Getting to Mars is just unbelievably hard.

You know, we've learned that the hard way.

Before--certainly you have to go back to the days before the rovers launched--

two thirds of the missions that have been flown to Mars had failed.

And they failed for all kinds of reasons--

rockets that blew up and spacecraft that just vanished with hardly without a trace.

MAN: 5, 4, 3, 2, 1...

Engines start.

We have liftoff from Earth to planet Mars.

NARRATOR: If you are ever lucky enough to book a flight

on the first rocket to the red planet,

you'd better be sure you've packed everything.

The one-way trip is at least six months,

with no turning back if you've forgotten something.

CLARK: We can go to the moon and get back in a week.

It takes about three years to go to Mars and come back.

You have to carry your food,

you have to recycle your breathing oxygen and your water,

so it's a very, very major undertaking.

Within about three days, the Earth looks very small,

and within a week, it's just another star

and you suddenly are going to realize you're in very deep space

and it's going to be a long time before you can go back.

NARRATOR: Before we take this giant leap,

we need to be able to carry everything needed

for a three-year round trip with us.

This is a much larger effort than getting to the moon.

It's the Apollo mission on steroids.

CLARK: At this point we know

at least as much as the engineers knew

at the time that they agreed to land on the moon,

and they had only nine years.

So | think once the nation decides they really want to land humans on Mars,

the system can be designed and developed and built.

NARRATOR: Fast forward to the future.

After six months crossing the blackness of space,

things suddenly get a lot more interesting.

The combination of a high approach speed,

a thin atmosphere and twice the gravity of the moon

makes Mars one of the hardest places to land in the solar system.

Even for robots.

SQUYRES: You hit the top of the Martian atmosphere

and you're going Mach 27--

27 times the speed of sound--

and for our vehicles

between when we hit the top of the Martian atmosphere

to when we were bouncing on the surface with the air bags was 6 minutes.

It's a hell of a ride.

You use a heat shield to slow you down

to a leisurely Mach 2, twice the speed of sound.

And then we throw out a supersonic parachute.

NARRATOR: Everything is complex,

and everything has to happen precisely on time.

SQUYRES: The worst part is when you come into contact

with the Martian surface.

There's no runway, okay.

There's no nice place to land,

and you can't control very well where you're going to come down.

So you're going to come down in a field of rocks like this.

How do you guarantee

that your billion-dollar spacecraft is actually going to survive that?

The approach that worked for us with our rovers was great big air bags.

Bounce, bounce, bounce, bounce, bounce,

finally the vehicles comes to rest.

The Vikings used rocket motors,

and they just touched down gently on the surface

and they were fortunate.

It was just good luck.

They landed in a field of boulders like this

but they didn't land with one that was poking through the belly,

and it all worked.

You have to be good, and you have to be lucky.

NARRATOR: Want to step outside to take in the scenery

or pick up some rocks?

As familiar as it might look beyond the porthole,

Mars is dangerously alien.

The upside is that the low gravity will give you super jumping abilities.

The down, the almost complete lack of an atmosphere.

This is not home: there is nothing here to breathe.

To find similar conditions

of low temperature and pressure on Earth,

you have to travel three times higher than a commercial airplane,

to the very edge of space.

Planetary scientist Bob Brown

shows why you should keep your helmet on when visiting Mars.

BROWN: We have this, just a beaker full of water.

We're going to put it in this little chamber.

And attach a vacuum hose to the chamber.

And haul the air out of the chamber.

NARRATOR: As the pressure drops to Martian levels,

the water boils at room temperature.

BROWN: So If you were to take your helmet off on Mars,

the liquid in your face, especially, would start to boil

much the same as this liquid water started to boil.

And | guess | don't have to describe what that might feel like

or what it might look like.

NARRATOR: A medical travel advisory might say to keep your suit tightly fitted,

but so far no one's built a suit that'll work on Mars.

Existing spacesuits are simply too bulky, too heavy

and too complicated to wear

for the sort of regular activity required on the unforgiving surface of Mars.

CHRIS McKAY: Something we take for granted here.

We get up in the morning,

| put on a shirt and a pair of jeans and out I go.

So it's got to be routine, easy to use.

Many times | have been working out in the field

in the Antarctic or the Arctic

and | just have to take the gloves off,

because I'm doing something

that requires that quintessential human capability

of touch and feel and hold.

So my request to the engineers is give me a spacesuit with gloves

that will keep me warm and keep me pressurized

but still allow me to use my hands.

NARRATOR: Not only will you want to move your fingers,

you'll want to move around.

NASA's lunar electric rover

is a prototype for future missions to the moon and Mars.

It's part vehicle and part spacesuit.

MIKE GERNHARDT: | can just picture being there in a vehicle of this type

and looking back at Earth in the distance

and deciding to go EVA

and be in boots on the surface in 10 minutes,

which would just be a remarkable breakthrough.

NARRATOR: Astronauts can cover more ground

by living in the vehicle for weeks at time,

stepping outside when they want to

and back inside at the first sign of danger.

SQUYRES: Mars does not have a powerful magnetic field

the way Earth does,

so there's radiation from the sun,

also cosmic rays that are going to penetrate through spacesuits.

NARRATOR: An astronaut might get a 30-minute warning

of an incoming solar storm,

but less predictable is the risk of being hit by a meteorite.

Recent estimates based on fresh crater counts

suggest that up to 200 new holes

are blasted into the surface of Mars each year.

And even the Martian moons are not guaranteed to stay in place.

The days of Phobos are numbered.

Possibly an asteroid that once strayed too close,

the moon is trapped in a fatal gravitational embrace.

Every passing century sees it drop six feet closer to death.

In about 50 million years, its fall is expected to be complete.

The aftermath, if anyone is around to see it,

could be Mars with a bright ring of moon dust to rival Saturn's.

But events like this are not your real danger.

It's the day-to-day exposure to the cold, dry Martian environment

that will make a long stay tricky.

SQUYRES: It was 119 degrees Fahrenheit here yesterday.

A really, really, really hot day on Mars,

it would get up to about 30 degrees Fahrenheit,

and at night it goes to more than 100 below.

NARRATOR: Martian deserts are both frozen and sun-baked:

with no ozone layer, UV levels are so high

that any unprotected organism, even a Martian microbe,

will be burnt to a crisp within minutes.

A good hat is just not going to cut it.

So why not leave all the dirty work of exploring Mars to robots?

SQUYRES: One thing about humans

is that they have a capability to improvise on the spot,

even if you don't have the right tools with you,

that robots lack.

In Death Valley this stuff was wet, it got dry;

when it dried, it cracked.

We're investigating the idea that something similar happened on Mars.

You know, I'd love to be able to do this on Mars, and we can't,

but a human on the scene can improvise pretty well.

NARRATOR: Getting down and dirty on Mars will mean exactly that.

When an ill wind blows on the red planet, dust really does go everywhere.

About once every three years, local storms go global

and the dust can block your view for months.

It happened the very first time we sent a probe into orbit in 1971.

ZUREK: When Mariner 9 got to the planet

there was a giant dust storm

that had completely shrouded the surface from it.

SMITH: They could see nothing, nothing, just dust.

And as the dust started to recede

all of a sudden these dots appeared.

There were three of them lined up.

What the heck are those?

It turned out to be the peaks of the three great volcanoes on Mars.

ZUREK: And that's when we began to realize

just how varied the terrain and topography of Mars was.

NARRATOR: This was the moment that Mars began to reveal itself:

a world with a secret history and the spectacular scenery to match.

Thanks to our sharp-eyed spacecraft, Mars is opening up like never before.

These are real landscapes that humans will one day marvel at in person.

SQUYRES: If you were going to Mars, you'd want to go for the scenery, right?

| mean, you're not going for the culture,

you're not going for the climate,

so you definitely want to go for the scenery.

One thing that people forget is that when we've landed on Mars

we have to go to places that are safe,

and safe equals pretty smooth and flat.

NARRATOR: Here's a bit of Mars that's anything but smooth and flat:

the magnificent Valles Marineris.

This titanic canyon system,

over 2,500 miles long and 6 miles deep,

is probably the grandest geological feature in the solar system.

It's clearly the red planet's must-see destination.

DAVID SOUTHWOOD: As a human being

it's the sheer gigantism of Mars that is amazing.

The Valles Marineris beats the Grand Canyon hollow,

and if you've ever seen the Grand Canyon, you will never forget it.

NARRATOR: It's so colossal,

the Grand Canyon would be easily swallowed by one of the smaller side branches.

ZUREK: We're talking about something here

that's the width of the United States or of Australia across here.

SQUYRES: | think the Valles Marineris would be the place to go.

Build a lodge right on the rim so you can look in.

NARRATOR: The attraction goes beyond sheer scenic splendor:

deeper than the canyon itself is the mystery surrounding its formation.

This giant fissure, once filled by mighty lakes,

has been scoured by floods of biblical proportions.

SQUYRES: You can make estimates

of how much water had to have been flowing

to carve these things,

and you get numbers like 100, 200 Amazon Rivers all cut loose at once.

Big, big amounts of water flowing across the surface.

NARRATOR: The other big attraction on Mars

is the largest volcano, and highest mountain,

in the solar system.

Olympus Mons towers at an astounding 17 miles,

three times higher than Everest.

Its base covers more ground than the United Kingdom,

and the massive caldera at its summit

could easily swallow greater London, Paris and New York.

SQUYRES: So things tend to be big on Mars.

| think in part that's because the planet has lower gravity,

so when you pile up lava, you can pile it three times higher

because the gravity is three times less

before it will start to collapse under its own weight.

NARRATOR: Mars is a far more active world than previously thought.

We see landslides of dust

and gullies freshly carved by outflows of mysterious fluid.

And this peculiar region has been claimed

as a flash-frozen sea, complete with fossil icebergs.

Likewise there are glaciers, geologically recent

but now buried beneath a protective blanket of dust,

waiting for the next change in climate.

Still, most of the defining surface features of Mars

were carved way back in the good old days.

SMITH: Certainly something happened in the early history of Mars

that led to great releases of water,

and of course people wonder with that much water

could there have been ancient oceans,

could there have been environments

that were very much like life environments

on the early Earth?

NARRATOR: Early Mars was a different world.

A world with a thicker atmosphere; with weather and water.

Possibly a vast, shallow northern ocean.

This was really the time to go to Mars:

when you didn't need a spacesuit,

perhaps just an oxygen tank and some warm clothes.

McKAY: When we reconstruct in our imaginations

Mars of three billion years ago,

we tend to make it like Earth, warm and cozy.

But it wasn't.

Mars, back in its wettest, warmest phase,

was probably like Earth today in its coldest regions.

So I'm imagining a place

where the snow and ice is melting in the summer

to form transient ponds and streams and ice-covered lakes.

It's cold, it's wet, but it could be rich with life.

NARRATOR: This is the Mars

that we want our astronauts to get their hands on,

to bring back and study--

the wet Mars of old,

where we might find the evidence of life.

If you want to find life on Mars, first you need to find water.

And not all of the planet's water story is ancient history.

There's been plenty of frozen underground evidence

detected from orbit,

but scientists needed to touch and taste it to be sure.

In 2008, they finally got their opportunity when NASA's Phoenix lander

made a daring approach to the high Martian Arctic.

MAN: 50 meters. Land init sequence initiated.

[applause]

SMITH: There was not ever more excitement in my life

than landing safely on Mars.

I've been through the opposite.

I've been through a landing that was not successful,

and | did not want that to happen again.

NARRATOR: The landing was not only perfect,

but the engines exposed suspicious white patches

directly underneath the spacecraft.

Water ice was just a few scrapes away.

SMITH: We did find water ice

and we found that the soil in connection to it

has calcium carbonate,

a compound that forms in the presence of liquid water.

If it had been wet,

then we wanted to look for nutrients and food sources

that could support microbes.

NARRATOR: The water ice is proof of a valuable resource

for any life forms still clinging beneath the surface,

and for future travelers.

SMITH: We now know that these plains that you see stretching behind me

are underlain only 2 or 3 inches deep by a sheet of ice,

all the way as far as you can see.

Great hockey rink.

If you had a hockey team on Mars, all you'd need is a broom.

NARRATOR: The possibility of running into Martians

received another boost

from a very Mars-like part of our own planet,

Chile's extraordinary Atacama Desert.

McKAY: The Atacama is special because it is just so profoundly dry.

Speaking roughly, it's 50 times drier than Death Valley.

It is deader than Death Valley.

It's the only place on Earth where Viking could have landed

and searched for life in dirt on Earth and not found it,

and instead found a reactive mixture of chemicals, the only place.

NARRATOR: Even here, in the driest corner of the driest desert on Earth,

life has confounded scientists.

Cyanobacteria have been found

living inside the rock-hard salt of a long gone lake.

BENITO GOMEZ: This is a halite, it's a sodium chloride salt,

which is colonized by cyanobacteria.

It's dark green because they have this particular pigment

protecting them from the excess of UV light.

NARRATOR: Once in a blue moon, a fleeting early morning ground fog

delivers some rare humidity to the air above the desert.

This precious moisture is greedily sucked into the microscopic pores

of the water-hungry rock salt.

GOMEZ: This is a very rare event.

So these bacteria are living in an environment

where liquid water is available a few hours during one year.

Very, very hard.

NARRATOR: If we're looking for Martian bugs,

we should search for life forms at least as tough and alien as this.

ROTHSCHILD: I'm looking at Mars from the point of view of a microbe,

and as a microbe | really need a very, very tiny amount of water.

| could probably live my entire life happily

in a tiny drop of water about the size of the point of a pen.

Now we've shown over the years

that organisms that live in salt crusts on the Earth

have enough sunlight coming in

so that they can go through their day-to-day activities

but still be protected from the radiation,

and we know there are salt crusts on Mars.

NARRATOR: Mars has a long-term wobble to its orbit

and every 5 million years or so,

the poles end up tilting 45 degrees toward the sun.

McKAY: A way of thinking about the Phoenix landing site

is think about the polar regions on Earth.

Imagine you're there in winter.

It's very inhospitable, very cold, very alien.

You think, how can anything survive here?

Come back six months later and it's like a different world.

The sun is shining, it's wet, it's warm,

things are alive and scurrying around.

So we may be being misled seeing this frozen, cold site,

and in fact, we're just there at the wrong season.

NARRATOR: We know that on Earth some bacteria can survive being frozen

for millions of years.

They can also eat perchlorate,

the highly reactive chemical Phoenix found in the Martian soil.

McKAY: Presumably, if there was life at the Phoenix site

it had learned the same trick.

And so there might be organisms that are literally eating the rocks

and reacting with perchlorate below the surface

shielded from the ultraviolet light

just having a great old time five million years ago.

The party is over because everybody froze,

but in another five million years the party will start up again

as the Martian summer comes to the north polar regions

and the ice turns to water.

NARRATOR: The party might not be over everywhere.

The gas methane has been found both by spacecraft in orbit

and by telescopes from Earth.

It's chemically impossible for methane to survive for long

in the Martian atmosphere,

so it must have been released recently.

SQUYRES: Now what makes methane?

Cows make methane; it's probably not cows.

Microbes of various sorts can release methane.

There are a variety of geologic processes.

Volcanoes can release methane.

So the mere fact that there's methane doesn't say life,

but either way the methane says that Mars is an active planet.

It's either biologically active or it's geologically active or both.

NARRATOR: The methane release appears to be seasonal

and linked to areas of suspected sub-surface ice.

Ice found exposed in fresh craters

has proven that water lurks not only near the poles

but also much closer to the equator.

It's pretty clear that if the Viking landers had dug just 4 inches deeper,

they would have reached this ice

and perhaps a totally different conclusion about life on the red planet.

ROTHSCHILD: So if Mars has any life at all,

whether it is so small you can only see it with a microscope

or if they had a mammoth, it wouldn't matter to me;

it's the whole question of is there life at all on Mars.

NARRATOR: Either way, there certainly will be life on Mars

the moment the first human traveler arrives.

In 2009, six men walked into a series of connected rooms

inside a warehouse in the Moscow suburbs

and shut the door behind them, for three months.

They took all their food with them and drank recycled water.

The only communication with the outside world

was electronic, with a 20-minute delay.

They were trying to simulate a flight to Mars.

There is no room to screw up on a trip like this,

mental or otherwise.

Once on Mars you are likely to be stuck there for a year or more

waiting for a window of opportunity to ride home.

And, unlike a robot,

the hopes and fears of the whole planet will be riding with you.

SQUYRES: | think that humans are going to do a better job

of exploring Mars ultimately than robots ever can.

Robots move really slowly.

Okay, what Spirit and Opportunity have done in 5 years on Mars

two astronauts could probably have done in a week.

NARRATOR: As fast and as smart as we are,

we still need mechanical help to scout the course for Mars.

The next robot rolling onto red dirt will be aptly named Curiosity.

SQUYRES: It's the size of a small car, and it has a nuclear power source,

so you don't have to worry about dust accumulating on solar arrays

or anything like that.

And most importantly it has the capability

to look for trace quantities of organic molecules,

SO we've gone beyond now looking for evidence of habitability

to actually looking for evidence of the building blocks of life.

NARRATOR: Whether it's alive or dead, a trip to this red planet

has a lot to teach us about our lonely blue one

and the universe beyond.

ROTHSCHILD: Now, if you have two planets

that are next to each other in the same solar system

that both had independent origins of life,

you would have to conclude

that the chance of having life all over the universe,

indeed even in other places in our solar system,

would be very high.

| think you could basically go to the bank and bet on it.

McKAY: We're not going to Mars just to search for life,

we're going to Mars to search for a second genesis of life.

We'd like to find something that's different from us,

that doesn't have the same genetic history

and genetic code that we have.

And, from my point of view, the more alien the better.

ROTHSCHILD: Now, the second possibility is that we find life on Mars,

but my goodness, it has a genetic code exactly like us,

it uses DNA.

It's too coincidental.

This is representing our cousins.

Life either arose on Earth and went to Mars,

or actually more likely that life originated on Mars

and it was transported on a meteorite or a comet

to the Earth early on

and in fact our home planet is Mars.

NARRATOR: So, in some ways a voyage to Mars

could be a voyage home.

Our ancestors have made such bold trips before.

When we walked out of Africa.

When we sailed over the horizon.

If it's technically possible, our ships will head out again.

ZUREK: We've always wanted to see what's over the next hill,

and Mars is that next "over the hill."

Sure, you're going to have be in a suit, you're going to have to have a habitat,

but it's a solid planet, it's got a surface,

you can see, you can work, you can explore.

CLARK: I've thought for about 30 years now

that we could go to Mars,

and usually when people ask me how long it would take,

I say 15 years

because we've been saying 15 years for the last about four decades.

SQUYRES: A human mission to Mars can't happen soon enough for me.

You know, I'm a robot guy.

That's what | do with my career

is build robots and send them to Mars,

but | also think that we send things to Mars for reasons other than science.

Our rovers Spirit and Opportunity

were built by people who, like me, grew up in the ‘60s

watching Mercury, Gemini, Apollo on TV as little kids

and dreaming of sending spaceships to Mars someday,

and now we do,

and | think as people watch

the first human explorers on the surface of Mars,

they are going to be similarly inspired

to do things that | can't even imagine at this point.

It's going to be very costly, it's going to be dangerous,

but | think it's something I'd certainly like to see happen.

I'd love to see boot prints in our wheel tracks.

| would love to see boot prints on Mars.

NARRATOR: When the first human footprint is made on Mars,

it will represent more than a giant stride into space.

This one small impression will be proof

that humanity is once again on the move;

travelers once more moving beyond our comfort zone

to explore new lands and new opportunities.

And have no doubt, there are many worlds out there, ripe for exploration.