Original subtitles

It is really true

that you can only explore the solar system

for the first time once.

Ah, Voyager did that.

How could one be so lucky?

It's a dream and it came true.

Fifty years from now

Voyager will be the science project

of the 20th century.

The mission.

The big mission.

It opened our eyes to worlds,

to real worlds.

This may in the long run be

the only evidence that we ever existed.

Voyager to me was Homeric,

it was years of passing across the solar system

from one planet to the other

and then it was a week or two

of frenzied activity and discovery and conquest

and then it was, well, back in the boats,

oars in the water and then on to the next conquest.

It is the little engine that could.

Nobody really knows how it does it,

but everybody's rooting for it.

Every second, it goes to another place

where we have never been before.

Voyager takes the cake.

It's the most audacious mission.

Who'd have thought

that we'd actually be able to do that in 1977?

In 1977, a team of scientists and engineers

launched a mission of staggering ambition.

Voyager.

The initial idea was a grand tour of the outermost planets,

Jupiter, Saturn, Uranus and Neptune.

What were their atmospheres like?

Their moons?

At the time, our knowledge of these worlds was scant.

We knew a little because you can observe

from the Earth with telescopes.

We knew for example at Jupiter

that there were moons

Io, Europa, Ganymede and Callisto going around.

We knew that there were winds on Jupiter;

we knew about the great red spot on Jupiter;

we knew that there was trapped radiation,

so we knew there was a magnetic field.

It was big.

No, let's see, what did we know?

We knew they were all gas giants,

mostly made up of hydrogen and helium

and some methane on the outer planets.

For Saturn, we knew about the rings

and we knew about the major satellites,

but hardly anything more than that,

and it was all very fuzzy.

I had been staring at these planets

through some of the best telescopes on Earth,

and yet all I could see was fuzzy blobs.

Astronomers had worked pretty hard

to know what the physical make-up was,

there were some basic characteristics,

but their real nature, what they were really made of

and what the means, moons, were like,

we had none of that, just little glimpses.

Human beings are a curious bunch.

We want to know what's around the corner.

We have to go past that next bend in the road,

so it's some sort of innate drive, I think,

that we have, as a species.

One of the key things that made this mission possible

was gravity assist.

That is when you fly by Jupiter, you turn the corner

and you take a little bit

of Jupiter's orbital speed with you.

Like a slingshot,

so you better make sure Saturn's in the right place.

The positions of the outer planets

presented an opportunity.

A rare alignment meant the time

needed to cross the solar system

could be slashed.

It would go Jupiter boom, Saturn boom,

Uranus boom, Neptune boom.

The planets had to be lined up in just the right way

to allow one spacecraft to do that.

And that aligning up only occurs rarely.

That only happens once like once every hundred,

more than a hundred years.

...175 years, something like that.

Once every 176 years.

The previous time it happened,

exploration was wooden sailing ships.

It was named "The Outer Planets Grand Tour,"

and the cost of the mission was estimated to be

in excess of a billion dollars.

The NASA administrator went to the President,

and he said the last time the planets

were lined up like that,

President Jefferson was sitting at your desk, and he blew it.

So, Mr. Nixon laughed and said all right, just do two.

So, only two planets.

Jupiter and Saturn were officially a go.

It would be a less grand but still ambitious tour.

Yet the Voyager team

wasn't ready to give up on going farther.

As they assembled the spacecraft in a giant hangar,

some of them kept a secret goal alive.

We knew right from the get-go

that we were going to try as hard as we could

to extend the mission to go to Uranus and Neptune.

We designed that in from the beginning.

We knew that we were endowing Voyager with the option

if the chance was there to use it.

We didn't want to build anything into the design

that would have prevented us from going further.

So, it was a mission within a mission, yeah.

A group of scientists and visionaries realized

that these spacecraft would leave the solar system.

They figured don't let this opportunity pass,

you're going to throw a bottle into the ocean.

Put a message in it.

What would we want to tell intelligent aliens

about our planet?

What would we want to tell them about us?

The driving force behind the message

was the astronomer Carl Sagan.

Would you expect someone to find this record out there?

Is there something out there?

Well, nobody knows.

One of the great unsolved questions

is whether we're alone or whether...

Carl Sagan has become probably

the best-known scientist of the late 20th century.

He was a working scientist, he played a key role

in many of the NASA missions to the planets,

including the Voyager one.

He was one of the scientists on the Voyager imaging team,

but he also was the astronomer who as much as any one person

made the study of extraterrestrial life credible.

A comment by Thomas Carlyle,

a somewhat crusty old fellow

who upon thinking about the stars said,

"A sad spectacle.

If they be inhabited, what a scope for misery and folly.

If they be not inhabited... what a waste of space."

Carl Sagan was a good friend of mine,

and I called him up and said,

"Hey, would you be willing to undertake

to come up with something

for us to put on the Voyager spacecraft?"

He says, "Yes, sure."

And he told me he could do it for 25,000 bucks,

so I authorized him to go ahead and do it,

and I sort of was hands-off at that point.

The Golden Record followed in the footsteps

of a project called the Pioneer plaque.

The Pioneer spacecraft had some line drawings

of a male and female form,

and some people went absolutely bonkers.

I don't know if you've seen it,

but it's the most innocent thing you can imagine,

and it caused a lot of commotion.

But I thought that was great.

At first Carl thought they'd simply do another plaque,

maybe with some more information,

but Frank Drake,

a brilliant theoretical physicist

but also a very hands-on kind of guy,

he came up with the idea

that for the same amount of weight and space,

you could send a phonograph record.

The people who actually did the science part of Voyager

are always jealous and mad

because the Golden Record gets more attention

than all the wonderful things they did

exploring the outer planets of the solar system

except Pluto and all that.

But the main attention goes to the Golden Record.

Because of the aura that surrounds anything to do

with extraterrestrial intelligent life,

any kind of effort to contact extraterrestrial life

is more fascinating than knowing the chemical makeup

of a mineral on Mars or something.

The record is an old-style LP recording.

The only difference is it's on metal,

and that's so it will last a long time.

And it was recorded at half-speed

so that gave us two hours of total time.

An hour and a half of it was devoted to music

and the other half hour contains

all of the other data on the record:

the natural sounds of Earth, the spoken greetings

and the encoded photographs of Earth.

One of the first questions a lot of people ask

is, well, they'll never figure out how to play it.

And in fact, we included

a cartridge and stylus in the package with the record,

and the drawing on the cover of the record shows the method

by which the stylus is to be placed on the record.

Maybe what's written on it

will seem like kindergarten scribbles to them,

but they should be able to figure it out

if they've got some smart minds or whatever's in their heads,

if they even have heads.

What I find interesting

is to protect it from the dust

and tiny particles of the journey,

they put a cover over it,

and on the cover was engraved the location of Earth,

our solar system,

in terms of its direction from different pulsars.

A lot of people said, well, why would you do that?

I said what do you mean?

They say, well, why would you announce where you are,

you know, because there are aliens out there,

that probably raid planets and use them for food

or eat the people or make them slaves.

You know, if they find it,

their technology is probably more advanced than ours,

they'll come here and destroy us,

so why would you do something like that.

Why would these people expose themselves

to our voracious appetite?

They must be very altruistic, you know?

In 1972, preparation for the mission got underway.

Other great journeys of discovery,

by Magellan, Columbus, Da Gama--

all involved more than one ship.

And so would Voyager.

Two spacecraft would be built, two chances for success.

One of the things I just admire most

about the engineers who built Voyager

is that they're always thinking

about the most improbable things happening.

You know, you want to take those people

on a camping trip with you because they will think of...

well, you've got to bring...

what if these bugs come out, what if the tent gets flooded,

what if you run out of gas,

what if you can't start the fire, you know.

They're the what if people,

and when you're sending something out into space

you can't go do a service call, you can't bring it back,

so your what if list had better be like that long

or you're not going to be able to survive.

These projects begin

with a conceptualization period.

How do we arrange the spacecraft,

how do we take the communications system,

this large 12-foot diameter fixed antenna,

and arrange it relative to the propulsion system?

The spacecraft took on the dimension of being a child,

and our design teams, you know, were like kind of parents.

This was actually a nurturing process.

Bringing that "child", if you will, into reality.

All spacecraft are made basically of the same things,

silicon and aluminum, that's about it.

You know, that's probably 95% of it.

Silicon and aluminum is cheap

until you start making stuff out if it, you know.

1972 was when you had the technology freeze,

remember we launched in 1977,

so you freeze technology several years earlier,

and at the time the biggest computers in the world

were comparable to the kinds of things

we have in our pockets today,

and I'm not talking about a cell phone.

I'm actually talking about a key fob.

What's wrong with 70s technology?

I mean, you're looking at me, I'm a 30s technology, right?

I don't apologize for the limitations

that we were working with at the time.

We milked the technology for what we could get from it.

Voyager is about 800 kilograms.

Its main antenna is 12 feet in diameter,

which was the largest we could launch.

There's this body,

this ten-sided can called The Bus,

and that's got all the electronics and the computers.

And that's got these arms and these appendages that stick out.

It has these feet that connected it to the rocket

and then a really long arm

with a magnetic field sensor on it over here

and another arm over there with this plutonium power supply

to give it its electricity.

You can't keep that too close to the spacecraft

because it will radiate the spacecraft.

And another arm with this device

that had the cameras and other instruments on it

that could point around, kind of like the eyes,

and the big antenna was the ears.

We had eleven scientific instruments

peeking out to see what's out there.

When everything is fully extended

to its greatest dimensions,

it's comparable in size to sort of a small school bus.

A strange-looking being for our planet,

but perfectly happy in space.

Beethoven's Fifth Symphony

was one of twenty-seven pieces of music

chosen for the Golden Record.

I became the producer of only one record in my career,

and only two copies of it were made,

and they were both hurled off the earth,

so I don't know if that's a credential or not.

The launch window for Voyager was set.

and they sure as hell weren't going to wait for the record.

We had six weeks to do it,

that's what always draws the biggest gasp,

that you had to figure out a way to explain the world to aliens,

and by the way it has to be finished in six weeks.

We had two goals in making the Voyager record,

we wanted the music to represent

many different cultures around the world

and not just the culture of the society

that had built and launched the spacecraft.

The other criterion was we wanted it to be a good record.

It's a very idiosyncratic message.

It doesn't seem like something made by a committee.

It's too quirky.

If you listen to the Voyager record,

it would be remarkable if you didn't hear some pieces of music

that were quite unlike anything you had heard before.

The Japanese shakuhachi piece

or the sixteen-year-old pygmy girl singing

what's called an initiation song,

a kind of puberty song,

in the Ituri forest of Africa is just unbelievably beautiful.

There was a certain amount

of hunting up rare records here and there.

I remember the back of an Indian appliance store in New York

where they had some Indian records,

and there was one copy of a raga

that we ended up putting on the record.

I would love to have had a Bob Dylan piece.

But really there's only room

for at most one contemporary rock piece.

But you know you're up against Chuck Berry's Johnny B. Goode,

which Bob Dylan himself would admit is an awfully good single.

It may be just four simple words,

but it is the first positive proof

that other intelligent beings inhabit the universe.

What are the four words, Cocuwa?

Send more Chuck Berry.

The world is full of fantastic music,

and it goes without saying there's a lot more great music

that's not on the Voyager record than there is on it.

Which is a good thing, too,

I mean, if you imagine living on a planet

that was so pathetic

that it only had 90 minutes of decent music.

In the summer of 1977,

final preparations for two launches began in Florida.

When it was launched,

it was of course all folded up, it was like origami.

Here was this almost unexpected encapsulation.

I mean, we knew that we were going to be encapsulated,

but the emotional effect on that was kind of surprising,

I noticed that in just looking around me.

I realized that this was the last time

any of us were going to see the spacecraft with eyes.

And, um, that's a f...

that's a fairly moving experience.

Journalists converged on Cape Canaveral

to cover a once in a lifetime mission.

When the reporters came to the launch,

they all wanted to know more about the record.

Most of the press release drawings

show the other side of the spacecraft

so you can't see the record.

There was always a lot of ambiguity in NASA about this.

There's no question that the Voyager record is useless

from a scientific standpoint,

and the officials reluctantly arranged a press conference.

The press conference was a joke really.

It was held in a hotel room

separated by one of those accordion folding barriers

from what was literally, as memory serves me,

a Polish wedding reception.

We did the whole press conference

with the oompah sound of a wedding reception next door.

But I think the public seemed to get it.

Environmental control, ready.

Roger.

We actually launched Voyager 2 first,

and this gave the media, uh, drove them nuts.

We launched Voyager 1 later,

but it was launched on a faster trajectory,

so it overtook Voyager 2 in December of 1977.

From that point on, Voyager 1

always got to the planet before Voyager 2,

and the press was happy, they understood it.

We have just had a report

from John Casani, the Voyager project manager,

that we'll be able to count down at 10:25.

After five years of planning,

the assembly of the spacecraft's 65,000 parts

and untold mathematical calculations,

it all came down to this.

Five, four, three, two, one.

We have ignition and we have lift-off.

You see those solids ignite,

and you are really not prepared for what's about to occur.

The sound waves then catch up and then this forceful shaking,

the body is actually moved in resonance with this energy,

shaking it, right.

We were sitting in bleachers,

and they keep you pretty far from the launch vehicle

because they can explode, and it's basically, it's a big bomb.

So there's a little bit

of holding your breath and wanting to make sure you see it

get that first little motion off the pad starting into space.

We were all thinking this thought:

There it goes, it's going to be out there to represent us

for the next five billion years.

There were outbursts of joy.

We were on our way!

And then we launched it,

and then other things went crazy.

The spacecraft began to do things

that we had no expectation that it would have done.

Voyager was not in control of itself,

it's just riding this big rocket,

and that was shaking it in such a way

that it thought it was failing,

and so it started switching off various boxes,

changing to the back-up this, to the back-up that.

Trying to figure out why all this stuff was happening.

As the launch vehicle leaves the launchpad,

it has to roll through a certain angle

to get to the right direction for departure,

and the rate that it rolls at is a much higher rate

than the spacecraft would ever normally experience flying,

and so the gyro hits the stops.

Us poor people on Earth,

we're like, "what is it doing?"

For a couple of days it was a real nail-biter.

People were asking us, have you lost the spacecraft

and we would say we don't know for sure

because we didn't know for sure.

And the headline read "Mutiny in Space."

The Voyager spacecraft had decided

it just didn't want to follow the instructions

that its human controllers were giving it

and it was going to do what it wanted to do.

So early in the mission it's like, oh, man,

is this mission going to be plagued with problems?

Is there some fundamental flaw in the design?

That was a cliff hanger.

That was the end of the mission.

It could have been the end of the mission.

Fortunately, the person

who had written that code

was able to say this is okay, it's doing this, it tried that,

it's doing this, it tried that and calm everyone else down.

The limits were set simply too tight.

It needed to be able to wiggle more and vibrate more.

Finally stabilized, Voyager 2 was bound for Jupiter.

The launch of Voyager 1 was coming up fast,

so the team scrambled

to fine-tune the spacecraft's software

to head off another mutiny.

With the launch window closing soon,

Voyager 1 finally took off.

But rocket science is famously complicated.

Centaur 6, Titan Centaur 6

has lifted off at 8:56 from here

at the Cape Canaveral Air Force Station...

We're thinking everything's okay,

and then we begin to hear that something wasn't right.

I looked over at him

and he looked like he was a little worried, you know.

And I said, "what's the matter, Charley?"

And he says, "I don't know,

I don't think we're going to make it, you know."

There was a leak in the propellant line,

and we were losing propellant overboard,

so while it was burning,

propellant was escaping from the launch vehicle

and second stage never got to deliver its full thrust

because it ran out of fuel.

And so, the upper stage which was a Centaur

liquid hydrogen and oxygen stage

had to make up for that.

And the Centaur is the stage

that's doing the guidance,

so the Centaur knows

that it's not reaching the required velocity,

and when it separates from the second stage

it knows it has to burn longer to add more velocity.

The Centaur had to use

1,200 pounds of extra propellant.

Now we're all thinking

is it going to have enough left in the tanks

or is it going to run out of fuel?

Fortunately, it had three and a half seconds of thrusting left

before it had run to fuel depletion.

Three and a half seconds,

so Voyager 1 just barely made it.

It wouldn't have gotten enough velocity

to get to Jupiter, you know,

so instead of getting to Jupiter, you know,

we'd have gotten almost to Jupiter

and then we'd come back toward the sun,

which would not have been good.

And then of course, you know, there's the thought

that it's out of our hands.

Now the major reason for this mission was about to unfold,

that is the science.

But our role as keepers,

as progenitors, as...

our role had been finished.

Thanks to the dedicated work

of hundreds of the world's best scientists and engineers,

the twin Voyagers had at last embarked on their odyssey

across the solar system.

The first leg was almost 400 million miles to Jupiter.

You can never really imagine,

you can try, but you can never really imagine

what mother nature will actually have in store

when you get there.

It's worth realizing that a human life ago,

less than 100 years ago, 87 years ago,

the universe consisted of one, of one galaxy,

our Milky Way galaxy,

in a static eternal universe with eternal empty space.

We didn't know about the other hundred billion galaxies

a single human lifetime ago.

In January 1979,

Voyager 1 was coming up on its first planetary encounter,

and Voyager 2 was four months behind.

It seems like time really flew.

I don't think we really fully understood

before the first Jupiter encounter

just how intense it was going to be.

No, we didn't.

We found out.

You start working on a mission in 1972,

you launch in 1977, all of that there's no science,

it's all getting ready.

And then March '79: the flood.

The encounters, they creep up on you.

When we were approaching, every picture

was the greatest picture ever taken of Jupiter.

In the beginning,

it would be just a little dot

getting bigger on the screen every day,

and as we would get closer and closer

the images became more dramatic.

Incredibly strange and beautiful,

and now by Voyager revealed in all of its splendor.

That acceleration as you're approaching encounters

is really something that becomes very, very exciting.

We called it drinking out of a fire hose, you know,

you're trying to take a little sip,

and this torrent of data is coming out.

Would someone care to speculate

what you would say to Galileo Galilei

if he walked into the room today?

How... how, how are you able to live so long?

I think Galileo...

Jupiter is more than ten times the diameter of Earth,

it's huge, and it's mainly hydrogen and helium;

there are no solid surface on these planets.

These planets are liquid, gas and liquid deep inside.

The gas is compressed

the farther down you go,

and it gets very hot indeed

and you would melt, vaporize, in fact,

if you tried to fly through Jupiter.

Let me first modify your statement,

not that it was wrong...

The atmospheric scientists got long-range views

because we weren't looking at tiny moons,

we were looking at the big planet,

and so we could see things going on

before the other groups could see things,

and we were always the first to start shouting.

Even to this day we don't fly color detectors.

You get a much higher-resolution image in black and white,

and so when we want to make color,

we take them through different filters

and then on the ground you put it together

and make a color image out of it.

You go to Jupiter

and you have a storm that's been around for more than 300 years,

that's the Great Red Spot.

You could fit two or three Earths inside it.

When Voyager started getting close-up images,

we realized that it was very active,

and that deepened the mystery

of how these big storms could even exist

with all this turbulence going on.

It was swallowing up clouds and spitting out others.

We knew that it was a vortex, but to see it in action...

Another feature of Jupiter's dynamic environment

posed a great danger to Voyager.

Powerful radiation might destroy the spacecraft's electronics.

Every day you're wondering

did we build the spacecraft well enough?

Did we anticipate all the possible things

that could go wrong?

You're approaching this monster magnetic field,

this monster radiation environment on purpose,

because you need to get close because you want to see

all the little moons and the clouds and the storms

and you want to slingshot on to Saturn,

but you just don't know if you're going to survive.

Thing gets fried, you lose the mission.

Still out there physically intact probably,

but unable to communicate with it, the mission's over.

Two months before shipping to the Cape for launch,

the scientists were predicting

that the magnetic fields around Jupiter

were intense enough that they would accelerate particles.

Whoa! We were hearing initially 40,000 volts,

that would be the end of our spacecraft.

Cabling on these appendages were conductors

that would take these destroying pulses

and just feed them right into our systems and kill us,

so we needed to ground everything.

We didn't have time

to go through the normal design reviews,

so in order to get this protection done quickly enough,

an ad hoc team was formed

and we did some things that were out of the ordinary,

very out of the ordinary.

I can remember asking one of the technicians

to go out and buy aluminum foil.

It was the only material that was available to us.

Normally our procurement of spacecraft hardware supplies,

materials, are a much more sophisticated process.

We're actually cutting continuous strips

and then cleaning them with wipes and alcohol

and then finally wrapping these on all of our exterior cabling,

but yeah, same material that's in your Christmas turkey.

I don't think we created any shortage per se.

It may have been a local shortage

in the local grocery store for a few days

until they reordered right.

Your turkey wrapping is protecting Voyager,

and now fast forward, you know,

did we know whether we had done enough?

Voyager survived the onslaught

and went on to record signals that led to a discovery.

If you had the right kind of antennas

on your ears, you could go out and hear what we record.

I'm going to call them radio sounds

because we have to detect them with antennas.

Amazingly we heard all kinds of sounds.

Whistlers.

These things that go like that.

Yeah, whistlers mean lightning.

There are lightning flashes at Jupiter

that would go halfway

from the east coast of the United States

to the west coast.

That was the first detection of lightning

on a planet other than Earth.

The two Voyagers were poised

to study Jupiter's little known moons.

Having picked up 36,000 miles an hour

from Jupiter's gravity assist,

the spacecraft were now traveling fast.

When you're on a flyby mission,

there ain't no second chance.

We were getting pictures,

they were getting better and better,

and you could begin to see detail

as these moons got bigger.

You know the dread you have is that you don't want to see

a lot of worlds that look like Earth's moon.

Let's face it, it's dull.

I think everyone figured they would be

just battered ice-balls, you know,

kind of like the highlands of the moon,

nothing but impact craters.

And when we saw Callisto,

basically it's totally hammered, right,

it's saturated with impact craters.

Ganymede shows a lot of interesting grooves and ridges,

but it's pretty blasted with impact craters.

Every crater lasts for eons

because no forces were present to resculpt the surface.

The first two moons were dormant worlds.

And then as we went into the inner two...

You could not see craters on either one of them.

Well, this was encouraging,

because now we think maybe this mission

is going to find a lot of diversity.

Discovering this billiard ball smooth icy crust

of Europa with cracks in it

and what looked like plates of ice

that might be moving relative to each other,

the best explanation for that

is that there's a thick ocean of liquid water, salty water

underneath that icy crust.

More ocean water than on the entire Earth,

probably two or three times.

It's the largest ocean in the solar system

in a moon going around Jupiter.

And then of course, you know,

kind of the showstopper for Voyager, we get to Io.

Io, of course, Io was the star of the show

and we didn't learn that until after the encounter.

Everyone had gone home,

and Linda Morabito, an engineer whose job

was to find out the positioning and the orbit of the spacecraft,

noticed some bumps on images of Io.

I was on the mission

as a mission navigator,

and our job involved just looking back

over the shoulder of the spacecraft

to say, "Okay, one more picture of the realm of Jupiter,"

so it wasn't high-priority work.

It was an optical navigation image,

and Linda saw this strange thing on the limb.

An enormous object emerged, enormous.

And the first thing I said to myself: "What is that?"

And I'm like it looks like another satellite

in the picture emerging from behind Io.

An object that size, at that range, at that distance,

would have been seen from Earth, it was sufficiently large.

I felt with certainty, it's the only thing I knew,

that I was seeing something that had never been seen before.

This was an umbrella-shaped plume

rising 250 kilometers above the surface of Io

with volcanic activity.

I found the very first evidence of active volcanism

on a world beyond the Earth.

It was so hard to believe that a little moon

could have 10 times the volcanic activity of Earth,

which was the only known active volcanoes

in the solar system were here on Earth.

And then there's Io.

Suddenly we had realized

this was a different journey we were on.

Io's volcanoes can shoot lava

over 200 miles into space.

These eruptions are powered by Jupiter's gravity,

which endlessly compresses and releases the moon.

I wanted to say one other thing,

we've been saying that perhaps there's some funny way

in which Jupiter gobbles up all the things that are coming in

and doesn't let Io be hit by any.

Well, we aimed a spacecraft and went very close,

and had we missed we would have made the first impact crater.

The flyby is basically a week-long affair

that's 24 hours a day.

It's intense.

There will be a Voyager report

in 30 seconds.

Instant science,

because there's going to be a press conference that night.

This picture comes down,

and you've got three hours to figure out what's going on

and then tell the world about it.

Oh, no pressure there, right?

The confines of being a piece of biology

got in the way of that.

I mean, you got hungry, you got tired, you know,

you had to go to the bathroom,

I mean, you're going to miss something,

you don't want to miss anything

because every 48 seconds a new image would come down.

No one got any sleep during one of these flybys

when the spacecraft would go zooming past.

The photo labs were working day and night,

and people were sleeping in their cars.

It was just way too exciting to... to sleep.

During its Jupiter encounter,

Voyager revealed a feature of the giant planet

never seen before.

Jupiter had something in common

with its flashier neighbor, Saturn.

The engineer in charge of the camera came in,

and he was like, "Candy, what have you done?

What is the matter with our camera?"

And I looked at it and went, ah, it's Jupiter's ring.

It went from being you've broken the camera

to, "This is the first picture ever of Jupiter's ring."

Jupiter was a game-changer.

Jupiter reset all the registers.

Now we're really up for something.

And to know that this was just

the very, very beginning of this journey.

If we're blown away by Jupiter,

just wait until we get to Saturn.

The journey to Saturn would take over a year

and bring Voyager and its message

one tiny step closer to other stars

where, just possibly,

intelligent aliens might discover it.

The Golden Record contained the call of a humpback whale

and greetings in 55 human languages.

Most were recorded at Cornell University,

where Carl Sagan was professor of astronomy.

My father was Carl Sagan,

and my mother is Linda Salzman Sagan,

and she's a writer and an artist

and she designed the iconic Pioneer plaque,

she actually drew it,

and she's the one who got all the greetings

for the Voyager Golden Record.

I like to think of her, that she kind of put together

a kind of a choir of voices of greetings to the stars.

The greetings to the universe

are almost like proto-tweets, the first tweets,

keep it short, keep it simple,

and there was a limit to what they could put on the record.

It's like kind of a tasting menu.

It's enough to get the aliens

to understand that, um, we're diverse.

My parents wanted a child

to have a voice of one of the voices,

and they just came to me one day

and said, "Nick, if you'd like to leave a message to aliens

if they happen to exist,

what would you like to say to them?"

Hello from the children of planet Earth.

"Oh, hello from the children of planet Earth,"

that's what I would say to aliens.

They loved that, and so it's like great, let's record you.

It's a bit of a blur.

Like the only thing that I know that I remember from that time

is those knobs and the little recording level

that goes into the red if you speak too much,

this 70s, kind of, um...

so I remember that,

and I remember watching the needle move as I spoke

and seeing where it got, oh, that got close to the red

but actually didn't go into the red,

okay, that's probably good.

And that was that.

And then I, you know, drank my apple juice

and went back to my books.

It was really not till considerably later

that the kind of enormity of what that meant actually hit me.

Well, that brings up the whole question:

Is there anybody out there?

Listen, there are, give or take,

200 billion stars in the Milky Way galaxy.

There are about 200 billion galaxies in the universe,

or at least in the universe we know about.

It's a pretty small spacecraft,

and it's a pretty big universe.

If you take a piece of sky the size of a soda straw

up there in the Big Dipper

in that tiny piece of what we thought was blank sky,

there's thousands of galaxies.

And each one of those galaxies

is filled with billions of stars.

That's just the soda straw,

and now you imagine the whole sky filled

with thousands upon thousands upon thousands of galaxies,

each of which is billions and billions of stars,

there's a lot of possibility out there.

There has to be other civilizations,

the numbers just compel it.

It would be almost statistically impossible

for there not to be other life forms

and other life forms that have evolved

to a state of intelligence.

But the chance that an intelligent alien

might encounter Voyager also hinges on another factor,

the sheer vastness of space.

The bigger you think space is,

the less probable it is you're going to find them

because they're needles in infinite haystacks.

If you want to realize how empty our galaxy is,

the nearest galaxy to our own is Andromeda,

it's about two million light years away.

It's on a collision course with us right now,

and in five billion years

that galaxy's going to collide with our own.

And you might say, "Oh, no, oh, no,"

but it turns out space is, even in our galaxy,

it's mostly empty space.

When our two galaxies collide,

almost no stars will hit any other star.

There's just a lot of room out there, a lot of room.

Once you start getting into the astronomical scales,

our solar system is pretty tiny,

and so this adventure of Voyager

which seems so remote and distant

for this little spacecraft to go out to the giant planets

is really just exploring the tiniest closest neighborhood

when you start thinking about cosmic scales.

The distances are almost unfathomable.

These were the fastest spacecraft

that had ever been built and launched and flown,

and they're traveling at ten miles per second.

You wouldn't even see it, right?

And yet, even at those

unfathomable by Earth standard speeds,

it takes decades, decades to get out there

into the outer solar system.

I'd like to know the answer, are we alone?

I'd like to know the answer to that question.

The big division with extraterrestrial life

is not space, it's time.

In our galaxy, our sun is relatively young.

The galaxy's about 12 billion years old,

our sun's four and a half billion years old,

there are many stars that are a lot older:

therefore, you could have imagined some civilization

around such a star that might have watched our Earth form

over the last four and a half billion years.

Well, over that last four and a half billion years,

the only evidence of intelligent life

would have been in the last fifty or sixty years

by watching Star Trek or I Love Lucy

or whatever signals we sent out, so even if you knew,

even if someone told you look at that star,

and then look at the third rock from that star,

and that's where you're going to find life.

Even if they knew which object to look for,

there's only a 50-year period over five billion years almost

where you'd be able to find intelligent life.

If we're alone, then we're truly unique,

and how did that happen and why us

and how are we so special

and yet in such a kind of far-flung

kind of humdrum part of the universe?

And if we're not alone, how did we all get here

and can we learn about ourselves by these other groups out there

and what are they like

and are they the creatures of our dreams or our nightmares?

In the fall of 1980,

Voyager got its first close views of the planet Saturn.

We started off with images

that were probably no better

than what you can get from the ground,

and then it keeps getting better and better and better

as you get closer and closer.

What are we going to see when we get really close?

Having seen Saturn in a telescope with the rings

just looking like these little tiny ears on either side,

to now seeing detail and the beauty of Saturn's rings,

you know, looking like,

almost like the grooves on a phonograph record.

The rings of Saturn, what are they?

Billions of icy particles, some the size of a house.

They're enormous, much wider than many Earths strung together

but less than a kilometer thick.

We get there and we find

that it's a blizzard of features throughout the rings,

and it got very complex.

We become junkies who...

This is how you become a planetary flyby junkie,

it's because you've gone through one of them

and you just know it's the greatest feeling

and you want to keep doing it again and again.

At some point, perhaps a year or so from now,

it may be possible to put all of this into perspective,

but right at the moment I cannot recall

being in such a state of euphoria

for any previous planetary encounter,

including our two remarkable Voyager encounters at Jupiter.

The largest moon of Saturn,

Titan's the most extraordinary place.

There's a dense methane atmosphere

where a complex organic chemistry has been going on

for perhaps billions of years,

and we are in a moment of extraordinary discovery.

We had both spacecraft programmed

to do identical missions at Saturn,

and that was the prime mission and it involved Titan.

There's a huge amount of scientific interest in Titan

because many people think that early in our own history,

our own planet may have been like that

with very little oxygen, lots of hydrocarbons,

very thick, different, smoggy atmosphere

that was changed dramatically on our planet by life,

so if you want to understand the starting conditions,

go study Titan.

If Voyager 1 was successful at Titan,

Voyager 2, which is nine months behind going to Saturn,

would be free to continue to Uranus and to go on to Neptune.

But it depended upon Voyager 1 succeeding at Titan.

Because Voyager 1 had to be in a certain place

in order to pass Titan,

it couldn't go on to Uranus and Neptune.

There was just no way to bend its trajectory

to go anywhere else.

Voyager 2 would have done exactly that same thing

if Voyager 1 had failed,

we would have gone like this, no more planets.

That would have been really tough.

You gonna try for Titan again and give up two other worlds,

Uranus and Neptune?

So there was a lot of pressure on Voyager 1.

Mostly what we looked at

was a giant ball of brown smog

with some sort of electric blue hazes above it.

Was it Voyager camera,

you couldn't see through the clouds and haze.

But the radio signal from the spacecraft

passed through the atmosphere of the moon,

and that gave them a measure of the pressure at the surface

and also the temperature at the surface,

and so we learned a lot about Titan from that radio signal.

Voyager 1 revealed a world

at nearly 300 degrees below zero Fahrenheit

that might have lakes of liquid methane

under its smoggy atmosphere.

Voyager 1 had succeeded.

And shortly after that, NASA Headquarters agreed

that we should continue with Voyager 2

on its Uranus trajectory.

Voyager 1, its planetary mission over,

sped away from the plane of the planets.

Voyager 2, in part to get on its trajectory to Uranus,

would have to fly dangerously close to Saturn's rings.

We're getting pictures and other data back from Voyager 2.

But at some point in time, it had to go behind the planet,

and that blocks us from getting radio signals to the Earth,

and that happened to be in the middle of the night.

It was a period of time, several hours,

that everybody knows we're going to be

out of contact with the spacecraft.

Everybody's expecting to pop champagne corks

and say "hey, we made it,"

and all the data's on the tape recorder

because it couldn't be transmitted to the Earth,

and instead it pops out of the other side,

and there's all these crazy error signals

coming from the spacecraft.

Something bad has happened.

Something happened

right around ring-plane crossing,

and the images that were coming back were blank.

People thought maybe it crashed

into the rings of Saturn.

Is this it, is it dead?

Okay.

Ladies and gentlemen, we can start the briefing.

I wanted to make a very brief statement.

We do have a problem on board the Voyager 2 spacecraft.

The spacecraft has a problem.

The scan platform operating mechanism

is not operating properly.

Make sure we understand where we're headed

for the following instruments are mounted on the platform:

the wide-angle camera, the narrow-angle camera,

the infrared instrument, the ultraviolet instrument

and the photopolarimeter.

A frozen scan platform

could be a fatal, crippling event.

Yeah, that was the darkest, the darkest day

of the whole mission.

There is circumstantial evidence...

I came into the auditorium,

and there was just gloom on everybody's face.

You're beginning to speculate.

I quickly learned what had happened.

The scan platform had frozen.

The problem is not with the camera,

it's with the articulated platform

that moves all of the instruments.

Our cameras, as far as we know, are working just fine,

it's just that we're taking lots of pictures of black space.

The rest of the Saturn mission

and Uranus and Neptune were dead.

And seeing everything that we were planning just gone,

just suddenly gone.

All of the science that we had hoped to do,

and Uranus and Neptune--

there were no other spacecraft

that were going to be going there.

It was up to Voyager to do it, and all of a sudden it looked

as though Voyager was not going to do it.

It was devastating, it was...

So, we've analyzed the slew data.

It took a couple of days

while the engineering team went to work diagnosing the problem.

We are going to command an azimuth slew

and an elevation slew to the Saturn position...

It turns out the scan platform

has small motors to rotate it,

and we could run it at slow speed,

tick, tick, tick, tick--

fast...medium speed or very fast.

We were of course wanting to look at lots of places,

so we had the thing looking lots of places,

and the lubrication wasn't adequate and it just jammed.

It was frozen sort of like a car

stuck in the, stuck in the snow.

You try to go forward or backward little bit...

and keep working on it and try to get it out,

and that's what we did with the scan platform.

We would try to push it a little bit in one direction

and it would yield a little bit,

and then we'd push it in the other direction,

and it would yield a little bit more,

and then we kept doing that back and forth, back and forth,

and finally that was enough

to get the lubrication into the gears.

It was freed up and back came the spacecraft

and back came the imaging system,

and there was Saturn on exit.

Yeah.

We were looking at the shadow of Saturn on the rings,

and it was clearly from this wild, crazy angle.

Wow. Holy cow, we're on the other side of Saturn.

We felt like we were there.

Nobody even thought about it.

Voyager was part of us.

We...

All of planetary exploration to me

is a story about longing, it's a longing to know ourselves.

It's a longing to understand the significance

of our own existence.

It's a longing to communicate,

to say to the universe we're here, you know, know us.

You know, where are you?

In the grooves of the Golden Record

was another gift from us to them.

The Voyager record has a set of pictures on it.

It depicts our civilization,

but we only had the ability to do about a hundred pictures,

that was as much data as we could send,

so that was kind of hard.

It was a process of distillation.

You can't describe the Earth

in a hundred pictures.

You can't describe the Earth in a thousand pictures,

but what art is about is taking something that's small

but can represent the whole.

We thought it was very important

to put some pictures of humans nude on the record

to show just what our anatomy and physiology was really like.

NASA had been seriously criticized

about the Pioneer plaque.

There were actually letters to the editors of newspapers

saying that NASA was sending smut to space.

For Voyager, NASA decided to play it safe.

Still, they gave the aliens some hints about our bodies.

Now it's five years of cruising out to Uranus.

Uranus would be the most remote object yet

visited by a spacecraft,

and it's so remote that it was not even known

until 200 years ago,

and it's a great distance out there,

and if we'd launched directly from Earth

it would have taken thirty years to get there,

so we were very fortunate

that we could swing by Jupiter and Saturn on our way.

I've been trying to figure this thing out

for the past 25 years,

and it's very frustrating in a telescope

to look at that tiny little disc,

so the next few days are going to be very exciting.

Once we got beyond Saturn,

essentially the engineers threw out the rule book

and said how are we going to make this work?

How are we going to take pictures of planets

this far from the sun?

Voyager was the first

of a class of NASA spacecraft that could be reprogrammed.

They could take what was on the computer

and just wipe it away

and give it a whole new set of software.

They trained the spacecraft to pirouette like a ballet dancer,

basically you want to take a picture of that thing

and it's going past you really fast,

so you spin the whole spacecraft and follow it like this,

and so even though it was darker at Uranus

and really dark at Neptune,

you could leave the shutter open without smearing,

and that was just beautiful.

We had all of the rich set of goodies

from Jupiter and from Saturn, but Uranus was unknown.

In January 1986,

Voyager 2 closed in on Uranus.

It would be by far

the most remote planetary encounter ever attempted.

It was like taking something

that was almost fictional, almost mythological,

and then seeing it as a real object.

Spacecraft flew through that system like a bull's eye

because Uranus is tilted on its side,

with this beautiful aquamarine blue methane atmosphere,

and all these pictures,

every single one of them is like whoa!

And you could hear people just, "whoa!"

And everybody would be doing something

and somebody would go, "whoa!"

And everybody would turn and look up.

"Oh, my gosh, look at that!"

There was no Internet,

there was no news stream going out to live CNN.

The only way to experience that sensation

of being one of only a small group of people

who saw a point of light become a world,

the only way to experience it was to be in that room.

Well, just about two minutes ago,

Voyager 2 passed through its closest approach to Uranus.

The new ring is right here.

Now, I don't...

you're telling me you can't see it.

I can.

Dr. Soderblom,

as you whizzed through your explanation,

I couldn't put it all together, could you try that again?

Slower?

Slower and a few more details.

I thought that was pretty slow.

Every time we arrived at a new planet

there were always surprises,

even though we had gotten a lot smarter.

For instance, before Voyager, all the magnetic fields

have the magnetic pole near the rotation axis of the planet,

and that was true for Jupiter, it was true for Saturn,

and then we flew by Uranus and the pole was near the equator.

There's been a lot of speculation

about the magnetosphere of Uranus.

Would there be one, what would it be like?

And the magnetosphere of Uranus

is far more weird and wonderful...

We found the planet's tipped on its side,

but the magnetic field is then tipped

relative to the spin axis,

so you have this huge contortion in the magnetic field

as the planet spins around, just bizarre.

At that point in its orbit,

the planet didn't look exciting,

and part of that is Uranus itself,

holding its secrets back.

That had to be, I guess, one of the...

well, disappointments in that Uranus

was not more photogenic than it was.

It was actually pretty blah.

Ah... poor Uranus.

Poor Uranus.

The big stars of the Uranus encounter

were actually the moons.

If you're going to go to Neptune,

you still have to use Uranus for gravity assist.

The gravity assist aiming point at Uranus

just happened to be pretty close to the orbit of Miranda.

If Uranus has been the last stop,

the scientists might have wanted to go to a larger moon,

which ironically, I don't see how anything could have been

any more interesting than Miranda.

It looked like a jumbled-up mess.

This moon looked like it had been ripped to pieces

and then just sort of shoved back together again.

Whoa! Come look at this.

Going up to the screen and pointing and saying,

"did you...look at that, look at that."

Nobody was ready for Miranda.

There were enormous cliffs and gashes,

one of them, you can see the edge of a cliff,

it's got to be ten kilometers tall.

The gravity on Miranda is so weak,

if you jumped off that cliff,

you could read the newspaper on the way down,

but when you hit the bottom

you'd still be going a hundred miles an hour,

so it probably wouldn't...

it would be the last newspaper you read.

At Uranus, Voyager detected intense radiation belts

and discovered two new rings and ten tiny moons.

We were just about to present all our results,

we were all about to have

the big final finale press conference and...

came back from breakfast,

and I went to go watch the shuttle being launched...

We have main engines start...

Four, three, two, one and lift-off!

Lift off of the 25th space shuttle mission,

and it has cleared the tower.

...and we thought, "okay, great,

we'll watch the shuttle launch

and then we'll go to the press conference."

But of course that was Challenger.

Engines throttling up.

Three engine now at 104%.

Challenger, go with throttle up.

Roger, go with throttle up.

People were just like astonished.

This gasp of like, "oh, my, did you see that,

did it really blow up?"

Because we had stopped in our meeting

so everyone could watch it,

and then there was just silence, people were crying.

Well, what can you say?

You knew right away that a bunch of people were dead.

Flight Throttle. Go ahead.

RSO reports vehicle exploded.

Copy.

And then of course they showed replays and replays

and replays over and over and over again.

We have no down link.

Okay, everybody, just stay off the telephones.

Make sure you maintain all your data,

start pulling it together.

The Challenger accident happened

as we were receding from Uranus.

I have this vivid memory of picture after picture

of the crescent Uranus coming back

and the replay of the Challenger explosion,

and it was just devastating.

Today is a day for mourning and remembering.

Nancy and I are pained to the core

over the tragedy of the shuttle Challenger.

We know we share this pain

with all of the people of our country.

This is truly a national loss.

I know it's hard to understand,

but sometimes painful things like this happen.

It's all part of the process of exploration and discovery.

It's all part of taking a chance and expanding man's horizons.

The future doesn't belong to the faint hearted,

it belongs to the brave.

During these closest approach time periods,

we would have hundreds of reporters come to JPL,

and when the Challenger exploded, everybody just left.

Those cosmic questions we hope to learn

by sending our machines out,

the very same questions that you and I and every child

has asked themselves.

Where do we come from, are we alone,

what's the universe made of, how will it end?

All of these basic questions

are the questions that drive science.

Finally at Neptune, Voyager has begun

the last of a decade's worth of encounters

with the outer planets.

It was another three and a half years

to get out to Neptune.

They had to reprogram the spacecraft again,

give it, teach it some new tricks,

to work in this even darker environment,

even colder environment.

If we take the Earth

being one astronomical unit from the sun, or AU for short.

Neptune is 30 times that distance.

When we launched Voyager,

there was no capability to get any images back from 30 AU.

That capability happened all after launch.

It involved taking two 34-meter antennas

and adding them to a 70-meter antenna.

Copy, we're ready to run that observation.

It meant using the entire Very Large Array in New Mexico,

27 antennas to collect the very weak signal

that we could get back from 30 AU.

The flybys past Jupiter, Saturn and Uranus

had sped up the spacecraft too, so it's going even faster,

so enormous amounts of pressure, and one shot.

In the summer of 1989,

Voyager 2 finally came up on the ice giant Neptune.

Thanks to slingshots at Jupiter, Saturn and Uranus,

the trip was almost 20 years shorter than a direct approach,

one without gravity assist.

There it was just sitting

out on the edge of our solar system,

waiting for somebody to come out and appreciate its beauty.

Just waiting for the day

that humans would get out there, and go wow!

I had been taking pictures of Neptune

from the ground where we couldn't see very much.

You know, in my head imagining what it might look like

and seeing that turned into reality, it's a rush.

Looking at this blue, bright blue orb,

it was evocative of the Earth,

which was bizarre for the last planet that we were flying by.

I was a meticulous log taker

and I would make little notations in these logs

and I would draw little pictures,

and you could see what's this little dark spot,

bright clouds, I'm like wow!

Wow! Exclamation point!

And I'd draw pictures and arrows.

The most surprising thing was a giant dark spot.

Nobody had any idea that would be there.

It's huge. It's like a hole in the planet.

So we called it The Great Dark Spot

because we're not very original when it comes to names.

We had to basically make a forecast

of the storms on Neptune

in order to point the cameras during the last day,

and at the same time there was a hurricane

off the east coast of the US,

and the weather forecasters

were trying to forecast that hurricane,

but they were trying to forecast it twelve hours in advance

and they were having a lot of trouble

because the storm kept changing position.

And we were just calmly plotting points on graph paper

and then said, "okay, two weeks from now,

this storm is going to be right here and it usually was."

At Jupiter, Saturn and Uranus,

the goal was to do a flyby

that would take the spacecraft on to the next planet.

When it came to Neptune

we knew that that was the last planet

that we were going to fly by,

and so we could take a different trajectory.

This allowed us to get a really spectacular view of the rings

and then look back on the system

in a way that was quite beautiful.

Think about imaging the rings of Neptune.

They have reflectivity which is twice as dark as soot,

and the light that's falling on them

is a thousand times fainter than on Earth.

So you have one one-thousandth the light

and you're trying to image something

which is twice as dark as soot against a jet-black background.

More than one ring can be seen even in the raw images,

the so-called ring arcs,

and it seemed reasonable that this was indeed the lost arc

that our imaging team raiders were looking for.

Oh, dear!

Now you're going to turn on me, right?

We knew at Neptune we wanted a close flyby of Triton,

which was a huge world around Neptune.

If you looked at them on the way in,

they weren't lined up.

One's up here; one's down here.

And so, what are you going to do?

Well, there was a way--

fly over the north pole, very close to Neptune

to bend the spacecraft so it would go down.

But the meant getting to within just a few thousand miles

of the cloud tops, skimming the surface.

And they had to hit that, you know, exactly right.

There was a lot of concern

that we didn't know enough about Neptune's atmosphere

to really be sure that the spacecraft would not tumble.

Just a slight error in the calculations

and instead of skimming across the cloud tops,

you're skimming into the clouds and the spacecraft burns up.

Slight error the other way, you go a little too far,

you don't bend enough, maybe you run right into Triton

and crash, and that's the end of the mission.

You don't have enough time,

you have to make your last best guess,

hit the send button.

It would have been just fascinating

to be hanging on to that spacecraft, right?

Skimming over these beautiful blue cloud tops of Neptune

and then as you come over the pole of Neptune

seeing that big moon Triton rise up...

After several billion miles of journey

to get us to within a few kilometers

of where we needed to be,

it's just absolutely remarkable.

You know, threading an incredible needle.

Southern hemisphere of Triton

is entirely covered with nitrogen ice,

and as we flew past, we were able to look down

at markings on the surface of the polar cap.

We were putting together a mosaic of Triton's globe,

but we couldn't get things to line up quite right.

Some of the dark streaks, two in particular would not line up.

He's like just scratching his head,

like I have no idea what's going on here.

This guy's one of the world's experts

on anything having to do with planets and moons,

and he can't figure this out.

I said, "well, let's put it in a stereo viewer,

red and blue glasses."

And the images fused into a three-dimensional model

and up popped these geysers.

And I said holy moly, and so we knew what we had.

These plumes.

Black geysers spewing out this stuff.

The plumes extending out of the surface

for like kilometers.

We were seeing eruptions on a world

which should have been just a frozen cinder.

This is too much.

The last place we would have expected

to see further dynamics, further eruptions

was at a moon this remote in the solar system.

Just because an idea's crazy,

it's not necessarily wrong.

Geysers. Volcanoes on Io.

Hints of a giant ocean of liquid water

under Europa's icy crust.

Each of these features is evidence of a source of energy.

And that's a prerequisite for life as we know it.

We knew this was the last planet

Voyager would explore

before it headed on for the rest of its journey,

and so I think the times together as a team,

the times to look at the pictures, talk,

meet together, became more precious.

I was passing by the secretary's desk

and she said, "Oh, Candy,

there's a reporter that wants to talk to you."

And he said, "The countdown clock

just went from minus,

counting down, to counting up."

Voyager's now leaving Neptune.

And he said, "How does that make you feel?"

And in that moment, I dissolved into tears.

After the spacecraft went past,

it turned around and looked back,

and there's this beautiful crescent Neptune and Triton,

and people realized that's the end

of the planetary part of Voyager.

That's the last protocol,

the last thing we'll see in our solar system is now behind us.

We could have enhanced the color a bit

to make a somewhat prettier picture,

but out of respect to the Voyager spacecraft

we decided to show it to you just as it is.

The way I looked at it was,

"Gee, we did something really great."

Very, very successful mission.

A little weepy.

I mean it's... there was a lot of energy put into this mission.

We have ignition and we have lift-off.

Years of intense effort.

It was the end of a sentimental journey.

We did it.

We pulled it off, and that's important.

It is.

We had a big party at JPL,

Chuck Berry was there,

so that was a good send-off for Voyager.

Rock star moment and sail on Voyager.

And I'm going to go get some sleep

or maybe I'll do a little more dancing...

Thank you very much, Lou?

Meanwhile, Voyager 1

is still kind of cruising out there,

getting farther and farther out,

and a number of folks on the team,

including Carl Sagan,

had this idea that before we have to shut the cameras down,

let's turn around, look back towards the sun

and let's take a picture of our solar system

unlike any that had ever been taken before.

And there was actually opposition to it.

They just didn't want to do it.

They couldn't get their heads around

what would be the point of taking a picture

of the Earth and Jupiter and so on

because they're just going to be little points of light.

So, Carl being Carl

actually went all the way to the NASA administrator

and got him to direct the Jet Propulsion Laboratory

to take this series of pictures.

Absolutely zero science in it.

Absolutely none.

From a unique vantage point,

nearly four billion miles away,

Voyager 1's cameras turned homeward

to take family snapshots.

It was Valentine's Day, 1990.

When we did our portrait

of each of the planets,

I was the first person to look at the pictures

and I knew every blemish,

and so I could pretty quickly go blemish, blemish, blemish,

and I thought, well, where's the Earth?

Where? How could we... you know?

And then I realized there was a lot of...

there were a lot of streaks of light in that image,

and I realized, finally,

that the Earth was sitting in one of those rays of light.

You know, I just sat there for a while

just kind of realizing, "wow, that's the Earth, you know,

that's Voyager looking back at the Earth."

And then once I had sort of recovered,

I started calling people.

I called Brad.

"Brad, we got it." Called Carl, "Carl, we got it."

Called my dad.

And so this is a different kind of milestone

than the scientific milestones we've had.

One that is really symbolic...

I'm an imaging scientist, so I first realized,

"Oh, this didn't turn out

the way we thought it was going to turn out,"

and my first impulse is to take my hand

and wipe away the dust, because there was some dust on it.

Well, one of the pieces of dust that I wanted to wipe away

was the Earth.

But it didn't matter because in the hands of Carl,

he turned it into an allegory on the human condition.

And the next slide.

The Earth in a sunbeam.

And in this color picture

you can see that it is in fact less than a pixel,

and this is where we live, on a blue dot.

On that blue dot,

that's where everyone you know and everyone you ever heard of

and every human being who ever lived

lived out their lives.

I think this perspective underscores our responsibility

to preserve and cherish that blue dot,

the only home we have.

The two Voyagers still communicate with Earth

nearly every day.

It takes huge antennas to detect their faint signals,

now less than one trillionth of a watt.

The spacecraft continue to be tracked

as they begin the final part of their mission,

to travel beyond the edge of our solar system,

into interstellar space.

It's in this never traveled region between the stars

that Voyager and its Golden Record

will have a chance of being discovered.

At the time we were designing Voyager,

interstellar space, where the boundary was,

was totally unknown.

We had our eyes on the interstellar mission.

Are we going to boost the spacecraft

to get out of our solar system and into the galaxy?

It was a shot in the dark because nobody knew how far.

Uncharted waters.

The magnetic field of the sun can only extend so far,

it's a bubble around our star, all the stars have bubbles,

we can see the bubbles around other stars out there,

so we know that they have bubbles.

Where does our bubble end?

Somewhere beyond Neptune

is the edge of the bubble around our sun.

At the heliopause two forces balance--

the outward pressure of the solar wind

and the pressure of interstellar space.

But how far out it was, no one was sure.

We kept going

and years went by and years went by

and we don't detect the interstellar medium.

Throughout the 1990s,

still didn't find the edge of the bubble.

Throughout the 2000s,

still didn't find the edge of the bubble,

and then finally in 2012 Voyager 1,

which is going the fastest, which is the farthest,

started to see these funny things happen

to the squiggly lines.

This crazy spike.

And everybody goes, "Oh, is that it?"

And then it goes back to normal.

And then it was just literally one magical day in...

it was in August of 2012 that everything changed

and it was like pfff, just... popped out of the bubble.

Voyager 1 has left our solar system.

It's the first thing built by humans

that has left our solar system

and now it's in interstellar space.

NASA says that Voyager 1

has become the first man-made object

to reach interstellar space,

the cold dark region between stars.

And we've slipped the outermost grasp

of our solar system with Voyager 1,

the first human-made object

to venture into interstellar space.

It's a wonderful achievement, actually.

When you think of it, it's historic,

it's our first step out of our bubble

which has been around all the planets

and around the Earth essentially forever,

and now finally some little thing that we have built

has left that bubble and is in the space between the stars.

It was like humanity

had just become an interstellar species.

It was like knocking on eternity's door.

When the Voyagers' power sources go dead

and when the spacecraft can no longer send back

any useful information,

that's really the point at which the Golden Record

becomes the primary function of those missions,

that when everything else is turned off,

those records are still floating somewhere in interstellar space,

completing the last part of the mission.

The chance that advanced intelligence beyond us

would detect, "Oh, hey, there is a radiating body

coming into our area,

let's go out and find out what this bottle in the ocean,

what message it might have.

Now is that a grand mystery?

Whoa!"

I love the optimism of it,

I love the idea that these are things

that are meaningful to us,

maybe you'll find them meaningful, too,

hypothetical alien, and yeah, it just touches my heart.

One thing we know about a metal record

with these grooves engraved on it

is that information is good for at least one billion years.

The inside of the record,

which was more protected from cosmic rays,

two billion years or more.

There's no wind, water, rain, weathering,

there's no planets or comets that they're going to run into,

and over thousands, millions, billions of years

they're predicted to remain pretty intact.

Because there's no proof that there's anything

that Voyager's ever going to encounter,

ultimately, it's a story about us.

Voyager is rarely out of my thoughts.

Always some little part of me

is wondering where is Voyager tonight.

Whenever I look up at the night stars,

I look in the direction that each of them is going.

There is never going to be another mission like it.

It was the first and last of its own kind.

Maybe someday, another being might find Voyager

and at least know of our existence.

It's highly unlikely, but it's not impossible.

And that small possibility surely gives us hope.

Is the universe any different than it was then?

No.

But are we different?

Absolutely!

The thrill of the discoveries, reaching the heliopause,

completing the Grand Tour,

I mean man, our child has just made it.

We're the generation

that sent something out into space

that's not only going to outlive us,

it's going to outlive our star.

Four billion years from now when our sun turns into a red giant,

Voyager is still going to be trucking

out there through the stars,

and the songs of our time are going to be out there.

Chuck Berry is still out there...

We'll still be out there.