Original subtitles

♪ ♪

GENTRY: They told us we couldn’t possibly succeed!

NARRATOR: At the end of the 1960s

NASA starts work on its most daring planetary mission.

Placing two spacecraft on Mars -- to search for life.

DUKE: To say that that was an easy process

would be a huge mistake.

NARRATOR: Project Viking will challenge engineers to the extreme.

Not to build big -- but to build small.

ANDY: You’re talking about a biological laboratory,

and you’re shrinking it down to a box one foot on each side.

GENTRY: Who were we kidding, it would never work!

TOM: I’d say it almost brought us to our knees.

NARRATOR: To succeed requires a spacecraft that must work by itself

millions of miles from earth.

MATT: And if any of that goes wrong, it’s game over.

NARRATOR: As mankind plans a return to the Red Planet --

this is the story of the unsung heroes

challenged to make the first successful landing on Mars.

[♪ theme music ♪]

♪ ♪

NARRATOR: July 20th, 1976.

The Jet Propulsion Laboratory, California.

Project manager Jim Martin and his team of engineers

are on the verge of making history

by safely landing the Viking spacecraft on mars.

Almost 200 miles above the surface,

Viking 1 begins its critical descent.

[Radio chatter]

MATT: This must have been one of the most anxious experiences

one can imagine.

MISSION CONTROL: 59,000 feet...

NARRATOR: Every engineering device must work perfectly.

MATT: Your heat shield has to come off at the right moment,

your parachute has to deploy at the right moment...

MISSION CONTROL: Lander confirmed, parachute deploy.

ANDY: And then that last descent coming down to the surface.

MISSION CONTROL: Parachute separation... 177 feet per second.

HOWARD: We were at a critical stage!

[Phone ringing]

NARRATOR: Suddenly, Jim Martin’s phone rings.

HOWARD: Jim got a call from President Ford.

NARRATOR: The President’s on the line -- and he wants an update.

MISSION CONTROL: Good roll, altitude hold.

HOWARD: He told him he couldn’t talk to him now, he was too busy.

And he hung up on him.

NARRATOR: After seven years of planning,

all Jim Martin and his team can do...

MISSION CONTROL: 73 feet per second... come on.

NARRATOR: ... is hope Viking makes it safely to the surface.

♪ ♪

NARRATOR: The story of Project Viking begins in the 1960s.

With the success of its first manned moon landing,

NASA starts planning an ambitious planetary mission.

The destination -- Mars.

Although smaller and further from the sun than the Earth,

our neighboring planet has some startling similarities.

ANDY: It has seasons like the Earth,

its day is roughly 24 hours long like the Earth.

It even has ice caps like the Earth.

NARRATOR: The planet’s likeness to ours is so strong,

NASA designs Project Viking with one goal in mind.

JOEL: One of the overarching questions in all of science is,

is there life outside the Earth?

And that’s the unique thing about Viking.

Viking was a science-driven mission.

NARRATOR: At over 200 million miles away,

the search for life on Mars will test engineers to the extreme.

JOEL: To think we could do this was an absurd assumption.

TOM: We knew nothing about Mars at the scale of a lander

or nothing about what it was really like on the surface.

JOEL: We didn’t know whether Viking would sink in the dust,

we didn’t know whether we would hit a mountain.

NARRATOR: During the 1960s one reason Mars remains enigmatic

is the challenge in reaching it.

The Soviets and Americans launch numerous missions --

many ending in disaster.

ANDY: Mars is much tougher because it’s so much further away.

You have to be incredibly precise, the targeting,

the navigation through millions of miles of space.

NARRATOR: For Gus Guastaferro --

Viking’s deputy project manager --

it’s a journey full of unknowns.

GUS: Therefore we were gonna write a spec

that had a lot of TBDs in it

and we are gonna have to get these TBDs answered.

And you know what TBD is, it’s to be determined.

NARRATOR: The best way to search for life on Mars is to land there.

How to do that safely

is one of the engineers’ biggest challenges.

They must choose one of two options.

MATT: Option A was to send a lander directly to the planet

and have it land without going into orbit first.

NARRATOR: It’s called direct entry.

On arriving at Mars a flyby module releases the lander,

which descends straight to a predetermined location.

ANDY: You don’t go into orbit first.

You just come screaming in and you slow down,

you get to the surface.

So with direct entry you’re gambling big time.

You’re just coming in and hoping for the best.

NARRATOR: The alternative -- option B --

involves an orbiter that carries the lander.

On arrival they both go into orbit around Mars.

The lander then separates and descends to the surface.

It’s called the out of orbit mode.

For Viking design manager Norm Crabill,

option B has one big advantage.

NORM: If you do out of orbit, you establish an orbit

and take advantage of that and do some reconnaissance

and decide can I go in where I wanted to

or do I have to go someplace else.

GUS: And there is no better redundancy than reconnaissance

before the attack.

NARRATOR: Option B plays it safe with an orbiter

but adds an extra $70 million

to NASA’s most expensive planetary mission to date.

At the end of the 60s, fighting the Vietnam War

means America’s debt is spiraling.

An expensive mission to Mars is hardly a vote winner.

Congress slashes NASA’s budget,

making the cheaper option A the obvious choice.

MATT: It was, in fact, quite surprising

to many of the people involved in Viking

that NASA chose option B over option A.

NARRATOR: What’s more, the agency requires engineers to build

a second identical spacecraft, Viking 2, as a backup.

TOM: The rationale is that projects like Viking are rare,

and when you do them you should do them right.

NARRATOR: To pay for it NASA must spread the enormous cost

over more years -- delaying the launch to Mars from 1973 to ’75.

For mission designers like Gentry Lee, it’s a godsend.

GENTRY: After we first started the Viking project,

Jim Martin and all the rest of us knew that

we had bitten off more than we could chew,

but we didn’t really want to go to Congress or to the President

and say, "I don’t think we’re gonna get there by 1973."

NARRATOR: Viking’s complexity means every second will be needed

to design and build the spacecraft.

Searching for life on Mars

will stretch those involved to the breaking point.

♪ ♪

NARRATOR: Spring 1970. Engineers on Project Viking start

the challenge of constructing America’s first spacecraft

to land on Mars.

At the Smithsonian’s National Air and Space Museum,

it’s possible to see the finished lander,

designed to search for life on the Red Planet.

MATT: So, as you can see, the lander is quite large,

it weighs about half a ton,

and it carries a pretty robust instrument package.

It has a high-gain antenna for sending signals

directly back to Earth.

It also has two cameras that scanned the landscape

and, probably most importantly, a biological

experimental package for analyzing soil samples.

NARRATOR: If life exists on Mars,

scientists expect it to be found in the soil.

But that begs an all-important question.

ANDY: How do you look for life on another planet

when you have no idea what that life is like?

You start with the assumption that at some basic level

it’s going to be similar to life on Earth.

NARRATOR: On Earth the simplest lifeforms

are microscopic organisms. They’re also the most abundant.

Viking will search for similar microbes in Martian soil --

by looking for traces of gas produced

as they live and breathe.

To do this the landers will carry three

life-stimulating experiments.

A lamp will warm Martian soil

in the hope any organisms will react to light.

Another adds varying mixtures of water and nutrients

encouraging microbes to exhale.

The third adds drops of liquid nutrient --

nicknamed "chicken soup" --

coaxing any microbes to feed and metabolize.

If Martian life exists,

Viking will hopefully detect any gases the microbes produce --

proving their existence in the soil.

But engineering these experiments

is a phenomenal challenge.

ANDY: You’re talking about a biological laboratory, you know,

something that would take up a significant amount of space

in a scientist’s lab,

and you’re shrinking it down to a box

that’s one foot on each side, a foot cubed.

NARRATOR: Restricted by size and weight --

engineering Viking’s biological experiments requires

miniaturization on an unprecedented scale.

ANDY: And the thing is jammed with, you know, valves and pipes

and miniature ovens and Geiger counters.

It’s diabolical to even think of trying to do that!

And doing it on a timetable.

NARRATOR: 1972.

With three years till launch, keeping Viking on schedule

is the job of Jim Martin.

TOM: Jim was an extraordinarily demanding project manager;

nothing short of excellence was good enough for Jim.

NARRATOR: Jim runs a military-style operation,

devising a notorious strategy to deal with the challenges.

TOM: And his concept was a top 10 problem list,

and so top 10 problem list became

very much a part of the culture of Viking.

Sometimes the top 10 list had 11 items on it.

And I mean, it was almost depressing

as to how challenging some of these things were.

ANDY: And the biology experiments were on that list

for a very long time.

♪ ♪

NARRATOR: Incredibly, 40,000 parts are crammed into a space

not much bigger than a briefcase.

ANDY: I’m sure the engineers were tearing their hair out.

TOM: I’d say it almost brought us to our knees.

NARRATOR: But the task is about to get harder still:

combating an invisible threat -- biological contamination.

ANDY: In order to prevent any terrestrial bacteria

from going along on the trip, the lander had to be sterilized

before it was put on the launch vehicle and sent to Mars.

♪ ♪

NARRATOR: Earth microbes can create a false reading

and wreck the biological experiments.

Worse still, they can contaminate Mars --

irreversibly changing the planet.

To sterilize the half-ton lander,

Deputy Project Manager Gus Guastaferro

turns to a profession that kills microbes for a living.

GUS: We looked at the medical practice;

how they sterilize the equipment they have

that might touch the human body.

Why not use the same thing on electronic parts

and materials that we’re taking to the planet?

NARRATOR: During construction both spacecraft

are repeatedly disinfected with anti-microbial fluids.

But to be certain it’s sterile

the team makes a radical decision

to copy another hospital procedure.

GUS: And so we stole from them the idea of

baking our whole spacecraft in a big oven.

NARRATOR: Each lander is cocooned in a bio-shell

and placed in a 30-foot oven where nitrogen gas --

heated to around 240 degrees Fahrenheit --

bakes them for almost 2 days.

ANDY: I mean, you can imagine these engineers, okay, they...

they’ve gotta design things that have never been built before,

and now somebody comes along and says,

"Oh, by the way, everything you build

has to withstand this baking in an oven

of 240 degrees for 40 hours."

And they must’ve just said, "You’ve gotta be kidding me."

TOM: Think about putting your camera or iPad in your oven

and turning up the temperature

and leaving it to sit there for a few days.

That is what we did with the lander.

We couldn’t think of any other way that guaranteed

that we weren’t taking any Earth life to Mars.

NARRATOR: Over five years, every element of the spacecraft

is designed and tested --

hopefully ironing out each engineering pitfall.

Now, with Viking built,

it’s time to put the engineering to the test.

♪ ♪

Summer 1975.

Viking 1 and 2 will be launched on twin Titan rockets.

The responsibility falls to Andy Stofan.

ANDY: I launched rockets for NASA for 20 years.

It’s a strange job because it either blows up in your face

or it’s 100% successful. There is no in-between.

NARRATOR: Placing the spacecraft on a precise trajectory to Mars

means both rockets must launch within a narrow time frame.

ANDY: I was well aware of the importance

of the Viking mission, so anything that went wrong

with the vehicle would then lessen the probability

of getting the two Vikings off.

NARRATOR: August 20th -- Viking 1 gets away on time.

But technical problems delay Viking 2

to the last possible launch day -- September 9th.

Then something even the engineers can’t control

threatens to intervene.

[Thunder strikes]

ANDY: The weather became marginal from a safety point of view,

that’s the worry of getting struck by lightning,

either on the pad or during the launch.

NARRATOR: Project Manager Jim Martin

consults local meteorologists and makes a call --

stop the countdown and wait

for their predicted lull in the storm.

With just hours of the launch window remaining,

it’s an incredible gamble.

♪ ♪

Thankfully, the weathermen’s anticipated gap in the clouds

passes right over the cape.

[Engines firing] MISSION CONTROL: 1, 2, 3...

Viking 2 is launched -- with less than 5 minutes to spare.

ANDY: To the great sigh of relief of myself

and the Viking spacecraft people

who were sitting there biting their nails.

NARRATOR: The Vikings are on their way.

Now the team must wait almost a year

to get a shot at making history --

attempting the first successful landing on Mars.

June 19th, 1976. A defining day for the engineers.

Viking 1 arrives safely in Martian orbit.

At over 200 million miles, sending communications

takes around 20 minutes -- each way.

So when the lander makes its rapid descent,

it must be able to think for itself.

ANDY: To do that was a whole new engineering challenge

of creating an electronic brain

that could carry out all of those things on board.

NARRATOR: In the 1970s, computer code

is typically stored on plastic tape.

But sterilizing Viking at over 200 degrees Fahrenheit

creates a burning issue.

DUKE: Had we heated the spacecraft,

that much magnetic material would have melted away,

along with the tape and the storage system.

NARRATOR: Engineers require a radical rethink.

Viking sequencing expert Milton Holt thinks there’s a solution.

MILTON: And it looked like, hey, this is the way to go.

NARRATOR: It’s a metal storage device designed for the military.

It’s called plated wire memory.

ANDY: So on these strands of wire were the instructions

that would get the lander to do everything it had to do.

MILTON: It can withstand the sterilization

and it shouldn’t be too difficult to manufacture.

As we thought at that time.

NARRATOR: In fact, engineers face a painstakingly intricate task.

MILTON: It took 3,000 wires laid up by hand,

and the intersection of each of these wires

had to be totally in place

within the width of less than a human hair.

ANDY: This was like some kind of

old-world handcrafted creation, very precise work.

You could not afford to screw that up.

NARRATOR: The finished computer contains

all the information needed to land Viking on Mars --

with a memory a hundred thousand times smaller

than today’s desktop computers.

ANDY: This is going to sounds unbelievable today,

but that computer had 18,000 words of memory,

and they sweated blood to get every one of them on there.

♪ ♪

NARRATOR: July 1976. Now in orbit, Viking 1 uses its cameras

to give the team their first detailed view

of its preselected landing site.

TOM: And the first pictures were alarming,

and I really mean alarming.

NARRATOR: The landing sites were chosen from pictures taken

almost five years earlier, when the Mariner 9 spacecraft

orbited Mars.

ANDY: The Viking Orbiter pictures were a factor of 10

better in resolution. And the change was just astonishing.

NARRATOR: What appears smooth in the Mariner images

now looks decidedly dangerous.

ANDY: There were features that looked like giant fingernails

had scraped across the surface.

MATT: There were huge boulders, trash bin-size boulders

that could potentially kill the spacecraft if it landed there.

ANDY: I mean, this was not the place that you

wanted to throw a half a billion dollars’ worth of lander at.

♪ ♪

NARRATOR: But luckily, the original decision to orbit Mars

rather than head straight to the surface

buys time to search for a safer site.

MATT: But they still had some time pressure on them.

Viking 2 was on its way, and also the nation was watching.

ANDY: As the new pictures would come in

the scientists would look at them closely

and try to figure out, you know, based on counting craters

how rough is the surface likely to be in that spot.

DUKE: To say that that was an easy process

would be a huge mistake, because it just took

meeting after meeting after meeting.

GENTRY: First site, rejected. Second site, rejected.

We rejected the fourth one, we rejected the fifth one,

it’s now July the 10th or so and the second Viking

is about to get to Mars,

and we can’t manage two of them at once.

NARRATOR: After 22 intense meetings, Gentry Lee

and his exhausted team make the final decision.

GENTRY: 3 o’clock in the morning, we’re looking at the pictures

of the sixth site, maybe it was the seventh,

I forgot which one, and finally Hal Mazursky,

who was one of the most eloquent spokespersons

for exploration of the planets,

put his head down on the table and said,

"This is probably as good as we’re gonna find,

and I’m tired."

And so with that we decided we would go down.

NARRATOR: July 20th, 1976. With the landing site chosen,

it’s time to make the descent.

After final checks, the critical "go" command is sent,

and Viking 1 is released from its orbiter.

[Radio chatter]

GENTRY: I will never forget the moment that I first realized

all the intelligence that we had or did not have

had to be inside that computer, on board that lander,

heading for Mars.

GUS: And that separation, you know,

it’s lost its mother so to speak. It’s by itself.

And it has to get there through a sequence of events

that are pre-programmed.

NARRATOR: For the next three hours Viking

is completely dependent on its on-board computer

to safely reach the surface.

GENTRY: And there was almost a palpable sigh in the room.

And almost as one, everyone looked at his or her watch

and started, mentally, counting down, three hours -- so forth.

TOM: So apprehension, yeah,

I think there is a lot of apprehension.

NARRATOR: To successfully land, Viking’s key components

must each work perfectly -- starting with the heat shield.

ANDY: You’re screaming in at thousands of miles an hour,

and you hit this very thin atmosphere,

but you hit it at very high speed.

It’s got to be able to withstand that intense heat

of that deceleration.

NARRATOR: Next -- still traveling faster than the speed of sound --

Viking must deploy a giant 52-foot parachute.

ANDY: So for the first time we’ve gotta supersonic-parachute,

which is a whole design challenge in itself.

NARRATOR: A challenge Paul Siemers wrestled with

during Viking’s development.

PAUL: The first thing we did with the parachute

to qualify it for Viking’s flight was,

we put a model of it in the wind tunnel,

and we had a big surprise,

and that surprise was the parachute got torn to shreds.

This turned out to be one of the worst days of my career,

’cause I had to phone home to Langley

and tell them I had just failed a parachute.

♪ ♪

NARRATOR: Paul’s team discovers that at supersonic speeds,

turbulent air behind the lander

is too violent for the chute to survive.

The failure means instant promotion...

onto Viking Manager Jim Martin’s infamous top ten list.

PAUL: We made the top of the top ten problem list,

how about that one? [chuckles]

NARRATOR: Paul and the team must find a solution.

They realize that by unfurling the parachute further

from the lander, it experiences less destructive turbulence --

and remains in one piece.

Now, back on Mars, the parachute works flawlessly,

decelerating Viking to around 130 miles an hour.

But a safe landing depends on overcoming one final challenge.

Designing Viking five years earlier,

engineers decide to use three retrorockets,

slowing the lander to under 5 miles an hour at touchdown.

But they discover a major flaw.

TOM: The tests were basically catastrophic.

The propulsion system created so much disturbance,

it would have compromised the science.

HOWARD: If there was any life there, the heating was such

it would cook it, literally kill it,

so we couldn’t detect it if it was there.

NARRATOR: For engineers it’s back to the drawing board.

Instead of three large retrorockets

with damaging exhaust, they replace them with

a cluster of smaller ones --

with exhaust plumes that won’t cook the Martian surface.

PAUL: It resembled a shower head.

There were 18 nozzles on each engine,

and that solved that problem.

[Radio chatter]

NARRATOR: But has it worked?

Have the years of engineering toil

finally placed Viking 1 safely on the surface on Mars?

For everyone on the team,

the moment of truth is about to arrive...

MALE: 73.3 feet per second.

MISSION CONTROL: ACS is close to vertical.

MALE: Come on...

♪ ♪

NARRATOR: Jim Martin and the team at the Jet Propulsion Laboratory

count down the minutes to hear

if Viking 1 has landed safely on Mars.

Intern Andrew Chaikin witnesses the drama unfolding.

ANDY: And you know we were waiting and waiting and waiting,

because those radio signals were still en route

in that 20-minute delay from Mars to the Earth.

GUS: It’s like waiting for the bride to come down the aisle.

MISSION CONTROL: ACS is green. 1.5 degrees per second max, .2 Gs.

NARRATOR: Finally, after 20 agonizing minutes...

MISSION CONTROL: Touchdown, we have touchdown...

Fantastic!

ANDY: It was almost so fast that you couldn’t take it all in.

MISSION CONTROL: We have a touchdown time of 12 hours,

12 minutes, zero 7 decimal one second.

[Cheers and applause]

JOEL: And everyone started clapping,

and a great sigh of relief,

and it was just elation through the whole room.

NARRATOR: Seven years to the day after America lands men on the moon,

engineers successfully place the first spacecraft on Mars.

GUS: My father, he was born in 1896

before the airplane and the automobile were invented,

and he’s here, excuse me for choking up,

seeing his son enjoy landing a spacecraft on another planet.

It was just remarkable.

I would have given up all the money I have ever made

for that moment.

HOWARD: I think people just had to take a short time

to breathe in and out that we had actually made it.

NORM: They were passing out champagne,

and I had my first and only drink of champagne.

TOM: It’s hard to state the feeling.

I mean, it’s a feeling of combined relief and excitement.

TOM [Archive]: A job very well done.

I’m assuming that we must be sitting right on the X,

so everybody just did fabulous and couldn’t be more pleased.

Thank you!

[Applause]

NARRATOR: But there’s little time to celebrate,

as everyone eagerly awaits

Viking’s first picture from the surface.

TOM: The anticipation of the first image coming back from Mars

was extraordinary.

I recall sitting glued to the screen in front of me.

NARRATOR: With its unique cameras, it’s hoped Viking

will finally reveal Mars as never before.

ANDY: It wasn’t like a TV camera that would take

the whole scene at once.

It would take the scene line by line with a mirror

that nodded up and down,

and you would build up from left to right the entire scene.

GENTRY: And so we waited, and here’s the picture

in front of us, and on the left-hand side of the screen,

down starts coming pixels.

ANDY: And all of a sudden 5 lines of picture came racing down

from top to bottom, just 5 lines. Like that.

MALE: Here it comes. Yup, yup, that’s it that’s it. Oh...

But then a few seconds later, another 5 lines.

MALE: Rocks. That’s beautiful.

ANDY: And then another 5 lines.

GENTRY: And by the time it got to the footpad,

you could see the rivets, and I remember screaming,

"Look at those bleeping rivets." You could see them clearly.

♪ ♪

MALE [Archive]: It’s incredible to see that Mars is really there.

DUKE: You know we’re taking pictures on the surface of Mars.

Nobody has ever done that before.

GENTRY: There was not a dry eye in the house.

All of us just burst with joy,

because every single person on that team had lived in fear

that what we were trying to do was beyond human capability.

GUS: The damn thing worked!

TOM: We were there. We did it, and now the science can begin.

♪ ♪

NARRATOR: With Viking 1 safely on Mars,

what could be the most profound experiment in human history

can start.

The lander will gather soil to examine it for life,

using its sampling arm.

MATT: At the end of the arm there’s a scoop.

Once the arm has collected a sample, it can then be retracted

and turned to deposit that sample

into the biological experiment package.

NARRATOR: The on-board computer commands the sample arm to unfurl.

But with the engineers -- and the world’s press --

eagerly waiting, there’s a problem.

The scoop fails to extend.

GENTRY: Oh, my gosh, it was a panic time.

After all the glory of landing safely, would

still not be a success, and we couldn’t get any material.

NORM: If we couldn’t get a soil sample,

that would mean that lander was out of business.

TOM: There was a lot of apprehension ’cause

we didn’t know why at first it hadn’t moved.

NARRATOR: The engineers are dumbfounded.

With the Viking 1 mission in jeopardy,

everyone is scrambling to understand what’s gone wrong.

GENTRY: And that was when this young engineer came in,

and he looked at me and he said,

"I just went over the sequence.

Did you have a separate sequence to unlock the key?"

"Oh, [expletive]," I said. And I remember that distinctly.

And I said, "That’s it! That’s it!"

NARRATOR: The team can’t quite believe it.

A locking pin on the sampling arm’s protective shroud

has failed to drop free -- and the arm is stuck.

GENTRY: Any time we were testing on the Earth,

we never had the locking key in,

so we didn’t have a sequence

that removed the locking key first.

NARRATOR: Incredibly, engineers have overlooked

a vital part of the computer code that helps remove the pin.

The solution is to write and then transmit

the missing code to the lander.

But with 1970s technology, that’s easier said than done.

MILTON: Well, the problem was

the way you generated a computer program was

you had a deck of cards,

and there were holes punched in these cards,

and the position of these holes would tell you

what command to load into the computer.

NARRATOR: Working around the clock, the punch-card code

must be meticulously checked.

MILTON: You would be in there early morning,

2 or 3 o’clock in the morning,

you would put your deck in the computer, and it rejects it.

So then you got to go through this stack of cards

and try to figure out, why did it reject this thing?

Where did I make an error?

♪ ♪

NARRATOR: Milton and the team iron out every last glitch,

check the code works on Earth,

and then it’s radioed over 200 million miles to the lander.

Now they must wait.

TOM: The next day when we got the pictures back,

low and behold, the pin was lying on the surface of Mars.

And so we knew that this problem was behind us.

NARRATOR: But Gentry Lee is not quite off the hook yet.

GENTRY: So, I got to explain all this to the media,

and, of course, Jim said, "Don’t embarrass yourself by saying

you just forgot to unlock the thing."

So I made up a perfectly honest story

that made it sound much more complicated.

I said, "These instruments on Mars are very complex,

and you have to study the sequences very carefully,

and we found that we had made a slight error in the sequence."

That was true!

NARRATOR: Less than two weeks later, Viking 2

also makes it safely to surface.

Both landers sample Martian soil in their on-board labs.

What they find remains one of the most

contentious results in planetary exploration.

♪ ♪

The Viking cameras give scientists

their first close-up look at the surface of Mars.

But now all eyes are on the results

of the biological experiments

to see if they will detect microbes living in the soil.

JOEL: There were three experiments.

Two of the experiments gave results

that were not consistent with life.

NARRATOR: That leaves one last experiment.

Adding nutrients to coax any Martian microbes to feed.

What’s detected comes as a shock.

JOEL: The third experiment,

called the Labeled Release experiment, gave results

that in 1976 indicated there was life on Mars.

NARRATOR: But this positive result is controversial.

On analyzing the soil further, Viking is unable to find

any organic material -- the stuff that life is made of.

Creating a dilemma:

If there’s life on Mars -- where is the organic material?

GENTRY: One newspaper would say Viking found life,

and another one would say Viking did not find life,

and as a result everybody was confused.

NARRATOR: To confirm life, the science community

requires more robust evidence,

as planetary scientist Jim Green knows.

JIM: If each and every one of those instruments

gave us a positive indication that a reaction could occur

that was biological that they were measuring,

then we could be assured that it was life.

NARRATOR: But Viking provides ambiguous results.

JIM: Now that means the scientific community

couldn’t get behind the idea that life exists on Mars today.

NARRATOR: Even now the Viking results are hotly debated,

and the question remains -- does life exist on Mars?

JIM: Well, we wanna find that out.

NARRATOR: Beginning in 1997, NASA returns to the Red Planet

with a series of rovers, studying the environment.

Their results have added to the speculation

Mars might be able to support microbial life.

JIM: So now we want to go back

and we want to attack it in a different way.

♪ ♪

NARRATOR: At the Jet Propulsion Laboratory

the latest generation of engineers like Matthew Robinson

are designing a bold new mission -- with a twist.

MATTHEW: We want to return the samples back to Earth

so that we can process those samples with instruments

that have much more precision and much more capability

than what you can send to Mars.

NARRATOR: NASA plans to bring back to Earth

Martian soil and rock samples to analyze

for evidence of both present and past life.

Helping design the vehicle that’s going to select

the samples is Mars rover veteran Rob Manning.

ROB: Now we are building a new rover to land in 2020.

However, it does something that no other rover has done before.

JIM: It has the capability of drilling rock,

creating about a chalk-size sample full of history of Mars.

This is an enormous engineering challenge.

NARRATOR: Matthew and the team are experimenting

how to extract a sample.

MATTHEW: The way that we acquire samples is using a coring bit

much like a drill that you would get from a hardware store.

NARRATOR: The drill will be able to extract core samples

from soft sandstone to the toughest granite.

MATTHEW: Once we core into a rock, the robotic arm moves up

and it goes over to the rover.

ROB: This core sample will then be very carefully put

in a container that will then be left on the surface of Mars,

along with many other core samples

which will later be collected by a future mission

that will bring those cores back to Earth.

JIM: And that means a whole new generation of engineers

are going to tackle this problem now.

But they have one major advantage.

They have the knowledge that has been given to them by the

Viking engineers demonstrating how we can do this.

NARRATOR: It’s a lasting testament to the Viking team

that their technical achievements --

made almost half a century ago --

allow missions to land on Mars today.

ROB: It’s amazing and mind-boggling

that they were able to pull that off

at such an early time in human engineering history.

JIM: It’s like a symphony in many ways,

and each of these individuals played their part.

GENTRY: All I could think of was --

and I hugged the people around me -- "We did it! We did it!"

NORM: We did the impossible. This is a symbol.

This is my Mars ’76 buckle.

It was the biggest thing I have ever been involved with,

and it worked like I expected.

TOM: I have to confess I’ve got a real feeling of pride

of having being a part of it,

and the emotional feeling is still there.

That is everything I know, more than I know!

[Laughing]