Original subtitles

NARRATOR: Apollo 8--

a last-minute change

sets a mission on a dangerous new course.

JERRY BOSTICK: I said, "What?!

That's the craziest idea I ever heard."

(rocket engines ignite)

A lot of risk.

NARRATOR: Untried technologies

put to the test.

(explosion)

MICHAEL COLLINS: Any one of them can be a disaster

if it doesn't go perfectly well.

(explosion)

NARRATOR: It's the height of the Cold War;

two superpowers race to the moon.

They were beating us at every turn.

I want to be part of winning.

NARRATOR: A president's deadline looms.

JOHN F. KENNEDY: Landing a man on the moon before this decade is out...

There's just enormous pressure.

NARRATOR: Then, tragedy strikes.

MAN (on radio): Hey! We've got a fire in the cockpit!

DAVID MINDELL: "How are we ever going to get there?"

NARRATOR: A secret decision is made.

FRANK BORMAN: He said, "Close the door,"

so I realized that something was big.

(rockets ignite)

NARRATOR: A half-century later,

the legacy of this audacious journey affects us all.

(hissing)

NARRATOR: The mission that got us to the moon.

"Apollo's Daring Mission,"

right now, on "NOVA."

♪

Major funding for "NOVA" is provided by the following:

Major funding for "NOVA" is provided by the following:

(static buzzing)

NEIL ARMSTRONG (on radio): I'm at the foot of the ladder.

NARRATOR: It is perhaps the greatest technological feat in history.

ARMSTRONG: Okay, I'm going to step off the LEM now.

NARRATOR: Humans arriving at another world.

ARMSTRONG: That's one small step for man;

one giant leap for mankind.

(cheers and applause)

NARRATOR: Yet before the arriving could happen,

first there was the leaving.

(indistinct talking on radio)

MAN: ...pressurized.

NARRATOR: It's December 1968.

A space mission unlike any other begins--

Apollo 8.

POPPY NORTHCUTT: It was the most dangerous mission of all.

BOSTICK: It was the boldest move

that NASA ever made.

NARRATOR: Three men--

Frank Borman,

Jim Lovell,

and Bill Anders--

are departing on a journey no one has ever made before.

COLLINS: For the first time

in human history, humans left earth.

NARRATOR: All previous missions have stayed in earth orbit.

But these three veteran fighter pilots--

Lovell from the Navy,

Borman and Anders from the Air Force--

will take their spacecraft to another world.

Apollo 8 will orbit the moon ten times;

it will not land.

But this mission will make the landing possible

by testing key technologies needed to reach the moon:

a giant rocket, a redesigned spacecraft,

a revolutionary new computer.

The rocket has never carried humans before.

The spacecraft and computer have flown only once,

on Apollo 7-- a mere 180 miles off earth's surface.

NASA WORKER: One, zero.

(rocket engines ignite)

(indistinct talking on radio)

NARRATOR: Apollo 8 will take these untried technologies

on a half-million-mile round trip

in the ultimate test.

MAN (on radio): We have cleared the tower.

MAN 2 (on radio): Roger.

BILL ANDERS: We probably had one chance in three

of making a successful flight,

had one chance in three

of not being able to do our mission

but at least making it home alive,

and one chance in three of not making it back.

NASA WORKER (on radio): Apollo 8, Houston, you are a go for staging, over.

NARRATOR: It is a giant risk.

(film projector humming)

But originally Apollo 8 was supposed to be a baby step--

just another test flight around the earth.

MINDELL: It took years of test flights.

And you really have to think, of course,

of the Apollo flights as a system.

ANDERS: It was the typical NASA

inch-by-inch, one-step-at-a-time approach.

NARRATOR: But in the summer of 1968,

years of careful planning and preparation are suddenly upended

by an alarming discovery.

JAMES LOVELL: We were training in California,

the three of us-- Bill, myself, and Frank-- when suddenly

Frank got called back to Houston.

BORMAN: Deke Slayton said, "Frank,

"I want you back here in Houston right away.

I have to discuss something with you."

NARRATOR: Deke Slayton is in charge of the astronauts.

And so I said, "Well, Deke, let's discuss it now, I'm busy.

I can do it over the phone."

And he reminded me who was boss.

Things weren't gentle

and politically correct in those days.

We weren't candy asses, okay?

(jet roaring)

And so I went back to Houston.

And he said "Close the door,"

so I realized that something was big.

NARRATOR: A CIA spy satellite has photographed

an enormous Soviet rocket on a launchpad.

It can mean only one thing.

BORMAN: The CIA had information

that the Soviets were planning on sending a man around the moon

in the year of 1968.

NARRATOR: A Soviet cosmonaut reaching the moon

would be a stunning defeat for America.

(explosion)

For years, the U.S. and Soviet Union--

both armed with nuclear weapons--

have been locked in a deadly cold war.

DEBORAH DOUGLAS: There was a sense

that communism was a profound threat

to democracy and to the United States.

NARRATOR: Starting in 1957 with Sputnik,

the Soviets open a new front: space.

DOUGLAS: Yuri Gagarin, Valentina Tereshkova,

blow after blow after blow.

They were beating us at every turn.

NARRATOR: In April 1961, a new president,

John Kennedy,

writes a memo about space that will have profound consequences.

HUGH BLAIR SMITH: He said, "Guys,

find me something we can beat the Russians at."

Now it is time to take longer strides.

I believe that this nation should commit itself

to achieving the goal, before this decade is out,

of landing a man on the moon

and returning him safely to the earth.

(applause)

NARRATOR: Kennedy has set a firm deadline: the end of the 1960s.

BOSTICK: It was a simple, one-sentence statement--

the goal and the schedule.

Clear, succinct-- no fuzz on that goal.

BORMAN: I never joined NASA to explore space.

Yeah, basically I was a military person,

and it was clear to me

that we were in a serious confrontation with the Soviets.

I want to be part of winning.

NARRATOR: Military test pilots-- now "astronauts"--

begin flying in 1961.

By 1967, Americans have mastered the basics of space flight

and all the techniques needed to reach the moon.

Apollo, America's moon program, is about to take its first step.

♪

Apollo 1 will be a test of the new spacecraft,

the command module, around the earth.

The crew is Gus Grissom, America's second man in space;

Ed White, who took America's first spacewalk;

and Roger Chaffee,

a Navy pilot who flew airborne photography missions

during the Cuban missile crisis.

(elevator gears whirring)

Three weeks before launch,

a dress rehearsal on the ground--

a practice countdown.

It's January 27, 1967, a Friday.

Things are not going well.

ENGINEER: Ah, who's transmitting?

GRISSOM: This is the command pilot, do you read me?

JOHN AARON: It was the end of a very frustrating day.

ENGINEER: You're pretty garbled here, Gus.

They were having communication problems with the crew.

GRISSOM: How we gonna get to the moon

if we can't talk between three buildings?

WHITE: They can't hear a thing you're saying.

GRISSOM: Jesus Christ.

When all of a sudden, you know, I thought I heard "fire!"

(on radio): Hey! We've got a fire in the cockpit!

NARRATOR: The fire quickly becomes an inferno.

And, you know, the rest is history.

NARRATOR: With no chance of escape,

poisoned by toxic fumes,

three astronauts perish.

BOSTICK: It was a pretty sad scene.

Most of the guys were sitting on their consoles

with tears running down their cheeks, you know,

just couldn't believe what had happened.

♪

MINDELL: Everybody knew what they were doing was dangerous,

but they didn't really think of it

as being dangerous on the ground.

And it was a huge shock that an accident like this would happen

in kind of an ordinary training scenario

without being in space.

♪

NARRATOR: Over the next few months,

the charred spacecraft is painstakingly disassembled,

each piece tagged, studied, and photographed...

(camera shutter clicking)

5,000 images in all.

♪

Sifting through these artifacts,

the Apollo Review Board pieces together what went wrong.

BORMAN: We came out with a scathing report

on the problems not only of the test

in which the fire occurred,

but also in the development of the spacecraft.

RAMON ALONSO: There was no ass-covering.

There was a lot of

soul searching as to what had happened

and all of the things that went with it.

NARRATOR: Electrical wiring shows shoddy workmanship.

Investigators believe the fire began

with a spark from a wire that had rubbed bare.

That spark quickly became an inferno,

because the command module was full of flammable material.

AARON: Everywhere you turned

there was stuff that would be subject to a flash fire

if you got the right ignition source.

NARRATOR: On top of that,

the atmosphere inside could not have been more dangerous.

LOVELL: Pure oxygen at 16 pounds per square inch.

Something which we all should have known,

that anything will burn

in pure oxygen at 16 pounds per square inch.

NARRATOR: And, finally, the hatch.

It's cumbersome to unlock, and it opens inward.

Expanding gases from the searing heat

meant tons of force held the hatch closed.

The fire is a shock to the system

that reverberates throughout Apollo.

It caused NASA to stop and reflect

on everything it was doing and redo it.

ALONSO: But for the fire,

there wouldn't have been the reexamination

of all kinds of things.

BOSTICK: We redoubled our efforts.

We said, "You know, those guys were our friends.

"And we're going to get to the moon,

on time, in their honor."

NARRATOR: But getting to the moon on time

won't be easy.

They've got to completely redesign the command module,

perfect a lunar lander,

figure out how to navigate to the moon and back,

and build a rocket larger and more powerful

than any that has ever flown.

It will be known as the Saturn V.

The key innovation that enabled all of Apollo

was the Saturn V rocket.

Without that, you couldn't even say we were going to the moon.

NARRATOR: It will weigh over six million pounds,

stand as tall as a 36-story building,

and be able to lift 130 tons.

America's moon rocket is the brainchild

of German engineer Wernher von Braun.

During World War II,

von Braun and his team develop the V-2 rocket.

Built with slave labor,

V-2 rockets kill thousands in London, Antwerp, and elsewhere.

After the war, von Braun is brought to the U.S.

to build rockets for America.

The Saturn V will be the biggest ever built--

if it can be built.

To get this enormous machine off the ground

will require a new engine,

ten times more powerful than any ever designed.

It will be called the F-1.

Sonny Morea is project manager in June 1962,

when NASA test fires its first F-1.

(flame roaring)

When we tried to fire it for the first time...

(explosion)

it just blew apart.

(explosion)

NARRATOR: As F-1 engines keep blowing up,

engineers finally identify the problem:

combustion instability-- uneven burning.

If you visualize a candle burning in a room,

it flickers from side to side.

Well, that's a form of instability.

What happens there is that it sees more oxygen on one side,

and so it produces more heat,

and it pushes the flame over to the side.

Well, that flips back and forth

maybe five or six times in a second.

That same phenomenon happens in an F-1 engine,

but they don't flip at five times in a second.

(explosion)

They flip 2,000 times in a second.

NARRATOR: Like a massive, out-of-control candle,

the fire inside the F-1 surges back and forth

until it destroys the engine.

They have no idea how to fix it.

The F-1 engine is simply too far ahead

of the state of the art, and too enormous,

to apply any known theory.

The solution had to come by trial and error.

You know, you find a way or make one,

that's the way it was back then.

It was absolutely the seat of our pants.

NARRATOR: If they can't fix the F-1,

Apollo is finished.

MOREA: If we couldn't solve the combustion instability problem,

we would not have gone to the moon.

It was too risky,

we would have killed a bunch of astronauts

trying to make that work.

(rocket igniting)

NARRATOR: So the engineers turn

to von Braun's original V-2.

Why didn't combustion instability destroy that engine?

In the V-2, liquid fuel and liquid oxygen were injected

through a number of separate nozzles.

In the F-1, fuel and oxygen are injected

through a single flat injector plate,

like a showerhead.

The engineers wonder,

did the multiple nozzles of the V-2

somehow divide the burning into separate zones?

If so, perhaps adding metal ridges-- baffles--

to the injector plate

would create a similar effect in the F-1.

MOREA: If we broke that into segments with baffles,

hopefully they wouldn't talk to each other,

similar to what the V-2 had.

NARRATOR: After many experiments with baffles...

(explosion)

...eventually they get the engine to run smoothly.

MOREA: Lo and behold, we found out

that the baffles were able to attenuate the oscillations.

NARRATOR: But how can they be certain the F-1 will work every time?

♪

They try deliberately causing the problem

by setting off a small explosion

inside the engine while it's running.

Can baffles stop instability after it starts?

We drove it unstable with a bomb.

We inserted a bomb right into the center of the injector

and blew it just at the time we ignited.

(explosion)

NARRATOR: With the engine running,

the small bomb explodes;

the burning becomes unstable.

But in a fraction of a second,

the baffles quickly stop, or dampen, the instability.

That would drive the engine unstable,

and then it would dampen out right away,

where before it wouldn't.

And every single time

those baffles dampened out

the oscillations.

(explosion)

♪

NARRATOR: In November 1967--

two years and one month before Kennedy's deadline--

the Saturn V rocket has its first unmanned test flight.

COLLINS: We got as close to it as we could,

something like two-and-a-half miles away.

NARRATOR: Among the spectators is astronaut Michael Collins.

COLLINS: When the engines ignited,

it didn't seem like a big deal.

And then the shockwave came.

(loud rumbling, forceful wind whipping)

And the shockwave got you in the viscera,

got you in the brain, got you shaking.

If you ever want to know what power meant, that was it.

NARRATOR: The five F-1 engines

and everything else work perfectly.

But leaving Earth on a rocket is just the start.

To reach the moon,

they'll have to cross a quarter-million miles

of empty space

and hit a target that's only about 2,000 miles across.

In space, everything is moving around.

I mean, the earth is moving around the sun,

the moon is rotating around the earth.

There's all this movement,

so how do you hit the target?

NARRATOR: To hit the moon,

NASA turns to Charles Stark Draper,

better known as "Doc"--

engineer, aviation pioneer,

MIT professor.

COLLINS: Stark Draper was the leader of the Instrumentation Lab at MIT,

Massachusetts Institute of Technology.

Very technical guy

who has put together this intricate bunch of equipment.

NARRATOR: Starting in the 1930s,

Draper develops a new way for pilots to always know

where they are-- even at night, in fog, or thick clouds.

MAN: On inertial and transfer power.

(engine rumbling)

NARRATOR: Inertial navigation.

It allows a pilot to navigate from point A to point B

without knowing any information other than where he started.

But on Earth,

points A and B are stationary with respect to each other.

In space, they're on two different celestial bodies,

Earth and moon, and both are constantly moving.

To reach the moon,

Apollo will have to speed up, slow down, change direction,

multiple times.

So Apollo needs the most accurate navigation system

possible.

It will have several parts.

The first is the inertial measurement unit.

Inside, gyroscopes measure changes in direction;

accelerometers, changes in speed.

Starting at the launch in Cape Canaveral, Florida,

by measuring every change in speed and direction,

it keeps track of the spacecraft's location.

But it's not perfect.

(dial clicking)

Gyroscopes and accelerometers are mechanical devices.

Each day, a little bit of error creeps in.

SMITH: In long missions like Apollo 8,

the inertial measurement unit

isn't quite constant.

It does drift a little bit.

NARRATOR: So the second part of the system

is a check on the inertial unit,

a way to correct its daily error:

the Apollo space sextant.

SMITH: After about a day,

you want to have somebody go to the sextant

in the wall of the spacecraft,

sight on a couple of stars,

and then basically correct the orientation.

NARRATOR: With the space sextant,

the navigator can determine the spacecraft's location

by measuring the angle

between a reference star and the edge of the earth.

Knowing that angle,

he can use trigonometry to calculate his position in space.

NARRATOR: Together,

the inertial measurement unit and space sextant--

combined with ground tracking--

will tell astronauts and Mission Control where they are.

But knowing where they are is only half the battle.

They'll have to maneuver into and out of lunar orbit.

And MIT thinks that's too hard for a human pilot--

it can all be done by a computer.

MINDELL: It needs just two buttons.

One button will say, "Go to moon,"

and one button will say, "Take me home."

NARRATOR: The astronauts respectfully disagree.

MINDELL: "No, no, no, no, no!

"I'm up there,

"it's my rear end that's on the line,

I need to be in control of the spacecraft."

ALONSO: The very first thing one of the astronauts said to me,

"As soon as we get up there,

we're shutting the sucker off!"

NARRATOR: But maneuvering the Apollo spacecraft

involves firing 16 different thrusters

plus the main engine.

So you better have 17 fingers and be awfully, awfully agile.

NARRATOR: After a long battle, NASA decides

the astronauts will control a computer,

and it will maneuver the spacecraft,

a system called "digital fly-by-wire."

MINDELL: Fly-by-wire is where

the pilot is really controlling a model inside the computer,

and then the computer does whatever it needs to do

to make the spacecraft fly like that model.

NARRATOR: The inertial measurement unit, the space sextant,

and ground tracking pinpoint where the spacecraft is.

The computer knows where they want to go.

So it figures out how to burn the thrusters,

plus the main engine, to get there.

Human life will be entrusted to decisions made by a machine.

MARGARET HAMILTON: A person's life was at stake,

in this case the astronaut, so it had to work.

NARRATOR: Margaret Hamilton develops software

that will control the Apollo computer.

DOUGLAS: Computers, they don't do anything

until they have some instructions.

That is the software side of things.

NARRATOR: Hamilton and her team will have to create software

that enables this computer to prioritize different tasks,

without freezing.

HAMILTON: We, the developers,

had to assign unique priorities to every job.

And if there's an emergency,

we wanted to interrupt everybody

and say, "Look, I'm coming in here

"for something that's an emergency,

everybody else gets downgraded."

♪

NARRATOR: And there's still one more requirement

for this new computer:

it must be tiny.

ALONSO: The way that the size of the computer got determined

was not by what it had to do.

Out of the blue, they said "Okay, here's a cubic foot,

fill it with computer."

"Computer" in the 1950s

meant something that was basically the size

of a building.

NARRATOR: It seems completely impossible.

But lead designer Eldon Hall thinks a new breakthrough

in electronics

might just be what they need.

SMITH: Eldon Hall said,

"The only way we're going to get small enough, low-power enough,

and reliable enough

is to switch to integrated circuits."

NARRATOR: Integrated circuits shrink hundreds of transistors

and other components down into one tiny chip.

But can such a computer be built?

Not only small, but able to prioritize tasks,

easy to use, and 100% reliable?

As the summer of 1968 arrives,

barely 18 months remain until the Kennedy deadline.

Then, the CIA brings the shocking news

that the Soviets are poised to send a man around the moon.

Rather than lose to the Soviets,

Apollo spacecraft manager George Low

proposes a radical change of mission.

Instead of orbiting the earth-- the original plan--

send Apollo 8 a half-million miles to the moon and back.

I said, "What?

That's the craziest idea I ever heard."

NARRATOR: Chris Kraft, director of Mission Control,

orders engineer Jerry Bostick to study the possibility.

BOSTICK: This is a Friday,

Friday afternoon, as a matter of fact.

He said, "You've got until Monday morning to figure out

if we can do it or not."

NARRATOR: The command module--

redesigned after the fire--

still hasn't flown;

the guidance computer hasn't been tested in space.

And the Saturn V,

which did so well on its first unmanned test flight,

had major problems on its second.

Still, the engineers conclude

this new mission might just work.

BOSTICK: We recognized that,

"Yes, this is not going to be a piece of cake,

but we can pull it off."

NARRATOR: The improved command module--

now with better wiring, a new easy-to-open hatch,

and no more pure oxygen on the ground--

will be tested around the earth first,

on Apollo 7.

If that works, Apollo 8 will go to the moon.

BORMAN: And all of a sudden

Jim and Bill and I began frantically training

for the lunar mission.

ANDERS: NASA usually went step by step.

In this case they jumped three or four steps.

LOVELL: Well, I thought that was a grand idea.

This was exploration;

this was a mini Lewis and Clark expedition.

(indistinct talking on radio, rockets fire)

NARRATOR: In October 1968,

the redesigned command module is tested around the earth

and performs perfectly.

Apollo 8 will proceed.

But first, a final review,

where engineers report to management and astronauts.

MOREA: "Can you give this a clean bill of health,

"that we have a safe mission ahead of us,

because of your hardware?"

Well, we had gone through

all this combustion instability stuff,

with many unknowns...

(explosion)

...and I couldn't say, you know?

Frank Borman put his arm around me, and he said "Sonny,"

he says, "we know you guys have done everything humanly possible

"to make this a safe flight.

"We're ready to fly.

Don't worry about it." (chuckles)

NARRATOR: Now, Apollo 8 will go.

It's December 21, 1968.

LOVELL: The morning of the launch, I thought to myself,

"We're going to the moon.

This is going to go to the moon."

NARRATOR: They've prepared as much as possible.

Still,

this launch is an act of faith.

♪

Whether it turns out to be a desperate gamble

that should never have been made

or a stroke of genius,

Apollo 8 is a leap into the unknown.

ANDERS: First on the Saturn V.

First to leave the earth, first to go into lunar orbit.

A lot of risk.

AARON: Was I nervous?

Yes, I was nervous!

That's a big step,

that's a big step.

MAN: Ten, nine...

NARRATOR: Eight seconds to go.

MAN: We have ignition sequence start.

NARRATOR: Fuel starts pumping,

15 tons each second.

(fuel igniting)

The F-1 engines come alive.

(engines roaring)

(indistinct talking on radio)

MAN: ...51 a.m. Eastern Standard Time.

ANDERS: It was so loud, we couldn't hear ourselves think;

couldn't even see the instrument panel,

it was vibrating so much.

It was one hell of a rocket.

BORMAN: You have seven and a half million pounds of thrust

pushing you;

all of a sudden it stops,

and you're flung forward in your seat belts

and then back

as the second stage took over.

NARRATOR: 11-and-a-half minutes after leaving the ground,

Apollo 8 is moving 17,000 miles an hour,

circling the earth.

Then, an unprecedented and momentous event.

The third stage engine will re-light

and send Apollo 8 out of Earth orbit

toward the moon.

It's a maneuver NASA calls, "TLI"--

trans-lunar injection.

COLLINS: "Trans-lunar injection"?

It sounds like some sort of a medical device.

NARRATOR: Astronaut Michael Collins is CapCom

the one person in Mission Control

who speaks directly to the astronauts.

COLLINS: I mean, I love NASA,

but they have an ability to transform, sometime,

the ethereal into the mundane.

NARRATOR: In this moment,

Michael Collins has the honor of announcing a turning point

in human history.

I said to them, "Apollo 8, you're go for TLI."

COLLINS: Apollo 8, you are go for TLI, over.

And Borman said, "Roger, Houston."

BORMAN: Roger, understand, we're go for TLI."

That was it.

I just really wish I had that moment to live over again,

because I would have said to them,

"Apollo 8, you can now slip the surly bonds of Earth

"and dance the sky, Apollo 8!

Dance the sky, you go!"

is what I would have said to them,

instead of, "You're cleared for TLI."

NARRATOR: The words may be mundane,

but the meaning is profound.

MINDELL: It was the first time that any human beings

entered the gravitational field of another planetary body

besides the one that we evolved on.

NARRATOR: Two-and-a-half days pass.

Even now,

the astronauts still can't see their destination.

Our blunt slide was towards the moon.

So we never saw the moon as we actually got right up to it.

NARRATOR: But they don't need to see the moon just yet.

To go into lunar orbit,

they have to fire their engine and slow down,

to be captured by the moon's gravity.

Everything about it must be perfect.

If not, they could miss the moon

or crash into it.

And all this done by the computer.

SMITH: The computer has to figure

how to turn the spacecraft

so the rocket is pointing in the right direction.

It then has to figure exactly when it has to be lit.

MINDELL: It has to be precisely calculated,

it all needs to be timed within tenths of a second.

NARRATOR: But the computer only does this

when the astronaut tells it to.

So, in 1968-- with no mouse, touch screen, or keyboard--

how will an astronaut talk to the computer?

MIT's answer is the display keyboard,

or DSKY.

MINDELL: It has a numeric keypad,

and a very simple,

what you would think of now as an LED display.

NARRATOR: The real genius of the DSKY

is the way it uses language.

REPORTER: To see the Apollo guidance and navigation system in operation,

we've talked with Mr. Ramon Alonso.

NARRATOR: Engineer Ramon Alonso was raised in Argentina.

Trying to create this language,

he remembers how he learned English.

ALONSO: When you go in school, somebody said, you know,

the parts of speech, part of sentences,

there's things called verbs, there's things called nouns.

"What is a verb?"

"Well, that's the action that does something."

"And what is a noun?"

"It's a thing."

So, all right, that seemed to suit.

I remember driving to work one time

and saying, "Oh, yeah, that might work."

"Fire Rocket,"

"Fire" would be 22,

and "Rocket" would be 35, or something like that.

And "Display Time,"

"Display" might be 16, and "Time" would be 45.

COLLINS: The DSKY was designed for idiots like me.

I mean, we had verbs and nouns,

so that it made more sense to us.

Very crude it was, but it certainly did the job.

NARRATOR: Now, almost three days after launch,

the Apollo guidance computer and its DSKY interface

are about to execute their first life-and-death maneuver.

LOVELL: We were coming up to what is known as LOI,

lunar orbit insertion.

NARRATOR: The computer must fire the engine at just the right moment,

in just the right direction,

for a precise number of seconds,

to drop Apollo 8 into the perfect orbit.

MINDELL: If you burn too much,

you could go in too a low in orbit,

that could intersect the moon.

Or you could fly off into an orbit

that won't come back around.

There's a tremendous amount of danger

with getting these orbital burns right.

NARRATOR: The LOI burn happens

when Apollo 8 is behind the moon.

Radio signals will be blocked, all communication cut off.

AARON: The break in communications is sharp.

The trajectory engineers could tell you,

based on the geometry and all the velocities,

exactly when that was going to happen.

BORMAN: This was a very important parameter,

because it would tell you when you lost your communications

if you were on trajectory or not.

NARRATOR: Everyone counts down the minutes to loss of signal-- LOS.

AARON: There was nothing to say.

You're just sitting there, and it's quiet as a mouse.

MISSION CONTROL: Apollo 8, Houston. One minute to LOS.

All systems go. Safe journey, guys.

APOLLO ASTRONAUT: Thanks a lot, troops.

See you on the other side.

At the exact second we were supposed to lose communications,

we lost it.

(radio static popping, ends abruptly)

And I said something like, "Whew!

We must be right on... right on time."

I said, "Yeah, Frank, it checked," I said,

"but, you know, they're our friends down there.

"they're going to pull the plug on that antenna

no matter how far off we are."

They probably turned off the damn radio.

(laughs)

NARRATOR: For the next 35 minutes,

there's nothing Mission Control can do;

Apollo 8 is behind the moon and unreachable.

AARON: It was almost a relief.

First of all, we'd been sitting there

for three or four hours with no bathroom break.

So, the first thing you do is you hit the door.

NARRATOR: Up in space, a different kind of break.

We saw nothing...

BORMAN: We were upside down and backwards

in perfect darkness.

LOVELL: ... until we rotated the spacecraft around.

Suddenly we looked down,

and there below us was the lunar surface.

♪

LOVELL: You know, we were like three schoolkids

looking into a candy store window.

NARRATOR: For the first time ever,

human eyes are seeing the far side of the moon.

On Earth, Mission Control won't know

if the burn to go into lunar orbit worked or not

until radio contact resumes.

NORTHCUTT: So we're sitting there waiting for them to come out

and have acquisition of signal,

to see whether or not

we all needed to jump into action.

Because if it went badly,

we really didn't have much time to do something.

NARRATOR: Poppy Northcutt is part of a support team

that will have to quickly compute emergency maneuvers

to bring Apollo 8 home if the burn failed.

NORTHCUTT: It was dead silent,

except for hearing the CapCom calling out,

"Apollo 8, this is Houston, Apollo 8, this is Houston."

MISSION CONTROL: Apollo 8, Houston, over.

Apollo 8, Apollo 8, this is Houston.

Apollo 8, Houston, over.

APOLLO ASTRONAUT: Houston, this is Apollo 8.

Burn complete.

MISSION CONTROL: Roger, good to hear your voice.

NARRATOR: The burn worked.

Behind the moon, the computer oriented the spacecraft

and fired the engine at just the right moment

for just the right time.

MINDELL: 60 by 170 miles

is the elliptical orbit they want to end up in.

And they end up with, like, 60.5 and 169.9 miles.

I mean, it's incredibly close, super-accurate burn.

NARRATOR: Over the next 20 hours,

Apollo 8 will circle the moon ten times.

It's Christmas Eve.

Before leaving the moon,

they'll show millions on Earth the view out the window

with a live television broadcast that almost never happened.

BORMAN: I was against it.

I didn't even want to take a television camera.

I was stupid.

Fortunately, the people at NASA overruled me,

because the American people and the people on the earth

had every right to see what we were seeing.

NARRATOR: But what should they say while showing the view?

BORMAN: I was told,

"While you're in orbit around the moon

"on Christmas Eve,

"you'll have the largest audience

that's ever listened to a human voice."

I said, "Gee, what do you want us to do?"

The response was, "Do something appropriate."

I'll never forget that.

Can you imagine that happening today?

We thought, "Can we change the words

to 'The Night Before Christmas'?

"You know, make it more contemporary?

How about something in the way of 'Jingle Bells'?"

Nothing that we could come up with seemed appropriate.

We ask each other, we ask our wives, we ask friends.

NARRATOR: In the end, it's Christine Laitin,

Washington insider and wife of writer Joe Laitin,

who has the answer.

BORMAN: And she said, "Well, why don't you start at the beginning?"

And he said, "What do you mean?"

She said, "Genesis."

ANDERS (on radio): For all the people back on Earth,

the crew of Apollo 8 has a message

that we would like to send to you.

"In the beginning, God created the heaven and the earth.

And the earth..."

I don't think anybody knew

they were going to do that.

ANDERS (on radio): "And God divided the light from the darkness.

LOVELL (on radio): "And God called the light day,

and the darkness He called night."

One of the most memorable things in my life, I guess.

It was very powerful.

BORMAN (on radio): "'...and let the dry land appear,'

and it was so."

AARON: The hair stood up on the back of my neck.

The first impression I had was,

"How appropriate."

BOSTICK: What could be better than having the first human beings,

Americans, circling the moon on Christmas Eve,

and they read the story of creation from Genesis?

I mean, it brought tears to my eyes.

BORMAN (on radio): "...God saw that it was good."

And from the crew of Apollo 8, we close with good night,

good luck, a Merry Christmas, and God bless all of you,

all of you on the good earth.

Wow! (laughs)

It just drained me.

NARRATOR: For millions on Earth,

the Christmas Eve television broadcast

is the defining moment of Apollo 8.

♪

But for the engineers, and especially the astronauts,

there's a critical maneuver just ahead

that overshadows everything else:

coming home.

"Trans-Earth Injection"

is the engine burn that will send Apollo 8 out of lunar orbit

and back toward Earth.

LOVELL: We're captured by the moon.

That means that unless that engine works

to get us out of here,

we can be here for a lot longer.

Is that engine going to work again?

NARRATOR: There's only one engine-- no backup.

It has baked in sunlight 250 degrees above zero,

frozen in darkness, 250 below.

BOSTICK: If the nozzle on the engine somehow overheated, or cracked,

or something, there's nothing you can do about that.

You lose the crew.

NARRATOR: Again, the burn will be controlled by the computer

and take place behind the moon.

COLLINS (on radio): Apollo 8, this is Houston.

Three minutes to LOS, over.

NARRATOR: Again, they lose radio contact.

(radio static popping, ends abruptly)

No one on the ground will know if it worked

until they acquire signal.

NORTHCUTT: Just watching that clock and wondering

what happened when they were on the back side of the moon.

What happened?

MISSION CONTROL: Apollo 8, Apollo 8,

this is Houston.

Apollo 8, Houston, over.

APOLLO ASTRONAUT: Houston, Apollo 8.

Please be informed there is a Santa Claus.

(laughter)

MISSION CONTROL: You're the best ones to know.

NARRATOR: Again, the engine worked.

For the next two-and-a-half days,

Apollo 8 will coast toward Earth.

Navigator Jim Lovell updates their position

with space sextant and DSKY.

So far, it's been flawless.

But MIT software engineer Margaret Hamilton

has a nagging worry.

How to prevent errors.

MINDELL: What if the astronaut types

something wrong into the DSKY?

♪

HAMILTON: My daughter Lauren would come in often

and would play astronaut.

And so she'd start pressing keys.

And I remember one time, all of a sudden...

(machine powers down, beeping)

big crash, everything stopped.

So I'm thinking, "What did she press?

She had selected P01 during flight.

NARRATOR: "P01" tells the computer that it's back on the launchpad,

waiting to start the mission.

If an astronaut enters that into the DSKY during flight,

the computer will forget where they are in space.

HAMILTON: This could happen on a real mission.

We have to stop the astronaut

from being able to select P01 during flight.

MINDELL: And NASA said,

"You know, these are the most highly trained test pilots

"in the world.

They're never going to make a mistake."

♪

NARRATOR: But, of course, they do.

A day-and-a-half away from Earth,

Jim Lovell is using the space sextant and DSKY

to update their position.

ANDERS: Suddenly,

Lovell said, "Uh-oh!"

MINDELL: Lovell is doing a star sighting,

and he's entering, "Star number one."

And by mistake he enters, "Program number one."

LOVELL: I got into a program that essentially told me

I was back on the launch site waiting to take off.

ANDERS: Borman wakes up.

"What's going on here?"

NARRATOR: The computer starts trying

to reposition the Command Module,

thinking they're back at Cape Canaveral.

BORMAN: The thing started turning and this,

and Anders didn't know what was going on.

Oh, he was mad that he could... (laughs)

I don't know, he's, "Lovell, you lost it.

You lost it!"

I said, "Well, don't worry about it."

NARRATOR: Using the space sextant,

Lovell orients the navigation system again,

putting it back on track.

BORMAN: Just one of those things,

you know, you can never trust an Annapolis graduate

very far.

NARRATOR: A day and a half later,

Apollo 8 reenters the earth's atmosphere

at nearly seven miles per second.

Ten minutes after that,

on December 27, 1968,

they splash down into the Pacific Ocean.

(applause)

The Saturn V rocket, the redesigned command module,

the guidance computer all have worked perfectly.

♪

(cheers and applause)

BOSTICK: We accomplished just about everything

that you need to do to land on the moon

except the landing itself.

(cheers and applause)

MINDELL: This is the moment that the Space Race ends.

(applause)

Once we do Apollo 8,

the Soviets are out of the running.

NARRATOR: Seven months later,

Neil Armstrong and Buzz Aldrin are walking on the moon,

thanks in large part to Apollo 8.

COLLINS: Apollo 11 walked on the moon.

Apollo 8 was about leaving.

If you consider the leaving and the arriving--

both of them necessary steps--

I think the two flights were about equal

in their historical significance.

NARRATOR: The legacy of this overlooked mission is profound.

Of all the Apollo technologies,

perhaps the one that touches more of us in our everyday lives

than any other is its pioneering computer.

MINDELL: This was a major moment

in the role of computers in the world,

and computers being able to let us do things

that we can't do any other way.

NARRATOR: With its DSKY and guidance computer,

Apollo paved the way for keyboards, mice,

touch screens,

computer-controlled airliners, factories, smart phones,

and more.

Now we have digital computers in everything;

this was the first digital computer in almost anything.

Now we stake our lives on software.

This was the first time people staked their lives on software.

♪

NARRATOR: Yet it's an old, analog technology

that gives us the most profound legacy of Apollo 8.

Assigned to photograph future landing sites

on the moon,

Bill Anders is stunned

by something else

that's completely unexpected.

When the earth came up in earthrise,

I didn't even have a light meter.

You know, I just started clicking away

and changing the f-stops,

and fortunately one of the pictures came out.

AARON: That picture is probably the picture of the century.

We thought we were going there to study the moon.

No!

We went to the moon, we learned a lot about the moon,

but most of all we learned about a new way to look at the earth.

BORMAN: The sense of isolation

and closeness of our humanity;

I wish more people would focus on it.

NORTHCUTT: Having that unifying experience, I think,

was a very profound and moving moment for people on Earth

to realize, "We're all on this one spaceship together,

we'd better start taking care of it."

NARRATOR: Before, all this--

seeing our home planet as it really is

and everything else;

the rocket, the computer, leaving Earth--

had only been dreamed of.

In December 1968,

it became forever real on Apollo 8.

AARON: This was the mission

that all that happened.

♪

NARRATOR: New Horizons--

the spacecraft that brought us to Pluto.

Now, in the farthest reaches of our solar system,

can it complete another mission--

a close encounter

with a mysterious object from the distant past?

NARRATOR: "Pluto and Beyond,"

next time on "NOVA."

♪

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♪