The Farthest

[wind blowing, static radio and chimes] [wind blowing, electronic sounds, faint radio chatter] [wind blowing, electronic sounds] [radio static, faint radio chatter] [wind blowing, wolf howling] [faint Morse code style beeping] LARRY SODERBLOM: It is really true that you can only explore the solar system for the first time once.

Ah...Voyager did that.

[whale sounds] TOM KRIMIGIS: How could one be so lucky?

It's a dream and it came true.

[Brandenburg Concerto No.

2 in F (Golden Record)] BRAD SMITH: Fifty years from now Voyager will be the science project of the 20th century.

The mission.

The big mission.

[Melancholy Blues (Louis Armstrong)] CANDY HANSEN-KOHARCHECK: It opened our eyes to worlds, to real worlds.

[aircraft/rocket noises] [faint plucked guitar string] FRANK DRAKE: This may in the long run be the only evidence that we ever existed.

[faint plucked guitar string] CAROLYN PORCO: 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.

[faint white noise] ["Wishing on a Star," Rose Royce] I'm wishing on a star to follow where you are I'm wishing on a dream SUZANNE DODD: It is the little engine that could.

Nobody really knows how it does it, but everybody's rooting for it.

...and I wish on all the rainbows that I've seen TOM SPILKER: Every second, it goes to another place where we have never been before.

...who really dream, and I'm wishing on tomorrow DAVE LINICK: 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?

I'm wishing on a star... [music finishes with final line] [soft piano] NARRATOR: 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.

[mechanical noises and piano music plays] ED STONE: We knew a little because you can observe from the Earth with telescopes.

DON GURNETT: We knew for example at Jupiter that there were moons: Io, Europa, Ganymede and Callisto going around.

[soft piano continues] STONE: 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.

[soft piano] CHARLEY KOHLHASE: 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.

[soft piano continues] TOM KRIMIGIS: 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.

[soft piano continues and rattling noise comes in] HEIDI HAMMEL: I had been staring at these planets through some of the best telescopes on Earth, and yet all I could see was fuzzy blobs.

[soft piano continues, chain rattling, squeaking, clanking] FRAN BAGENAL: 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.

[soft piano continues, now accompanied by light guitar] [sea and bird sounds] HANSEN-KOHARCHECK: 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.

[light guitar & glockenspiel music plays in the background] STONE: 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.

NARRATOR: The positions of the outer planets presented an opportunity.

A rare alignment meant the time needed to cross the solar system could be slashed.

[light guitar & glockenspiel music continues in the background] SODERBLOM: It would go Jupiter boom, Saturn boom, Uranus boom, Neptune boom.

HAMMEL: The planets had to be lined up in just the right way to allow one spacecraft to do that.

SODERBLOM: And that aligning up only occurs rarely.

HAMMEL: That only happens once like once every hundred, more than a hundred years.

JIM BELL: ...175 years, something like that.

KOHLHASE: Once every 176 years.

BELL: The previous time it happened, exploration was wooden sailing ships.

[guitar music continues] [ocean] KRIMIGIS: 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.

[electric guitar music begins] NARRATOR: 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.

[sounds of light turning on] KRIMIGIS: 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.

KOHLHASE: 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.

[percussion kicks in as music continues] JOHN CASANI: 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.

[heartbeat, bottle falls, water splashes] BELL: 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.

[high pitched string music begins] NARRATOR: 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.

WATERS: Would you expect someone to find this record out there?

Is there something out there?

CARL SAGAN: Well, nobody knows.

One of the great unsolved questions is whether we're alone or whether... JON LOMBERG: 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.

CARL SAGAN: 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."

[laughter] CASANI: 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.

BELL: The Golden Record followed in the footsteps of a project called the Pioneer plaque.

CASANI: 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.

LOMBERG: 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.

[harp music] DRAKE: 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.

[laughs] LOMBERG: 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.

TIMOTHY FERRIS: 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.

LOMBERG: 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.

BELL: 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.

[spraying sounds] KOHLHASE: 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.

CASANI: 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?

[whale sounds] [radio signals scrambling and faint radio chatter] NARRATOR: 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.

[birds and wildlife noises] BELL: 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.

[machines spinning and grinding] FRANK LOCATELL: 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.

CASANI: 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.

[beeping machines and low bass drum beats] RICH TERRILE: 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.

CASANI: 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.

ED STONE: Voyager is about 800 kilograms.

Its main antenna is 12 feet in diameter, which was the largest we could launch.

BELL: 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.

STONE: We had eleven scientific instruments peeking out to see what's out there.

BELL: 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 5th] [Beethoven's 5th] [music continues] [Tchenhoukoumen percussion, Senegal] NARRATOR: Beethoven's Fifth Symphony was one of twenty-seven pieces of music chosen for the Golden Record.

FERRIS: 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.

[needle sliding off record] [Izlel je Delyo Hajdutin (Golden Record)] The launch window for Voyager was set.

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

[Fairie Round--David Munrow] LOMBERG: 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.

[Melancholy Blues-- Louis Armstrong] FERRIS: 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.

[Ugam--Azerbaijan bagpipes] The other criterion was we wanted it to be a good record.

[Mozart--Queen of the Night-- Eda Moser] LOMBERG: It's a very idiosyncratic message.

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

It's too quirky.

[Mozart--Queen of the Night-- Eda Moser] [Cranes in Their Nest-- Japan (Shakuhachi)] FERRIS: 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.

[Pygmy girl initiation song] 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.

[Jaat Kahan Ho--India-- Surshri] [piano note] [cello] [cymbal crash] FERRIS: I would love to have had a Bob Dylan piece.

But really there's only room for at most one contemporary rock piece.

[electric guitar] But you know you're up against Chuck Berry's Johnny B. Goode, which Bob Dylan himself would admit is an awfully good single.

STEVE MARTIN: It may be just four simple words, but it is the first positive proof that other intelligent beings inhabit the universe.

LARAINE NEWMAN: What are the four words, Cocuwa?

MARTIN: Send more Chuck Berry.

[laughter and applause] FERRIS: 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.

NARRATOR: In the summer of 1977, final preparations for two launches began in Florida.

BELL: When it was launched, it was of course all folded up, it was like origami.

LOCATELL: 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.

[picture flash sounds] NARRATOR: Journalists converged on Cape Canaveral to cover a once in a lifetime mission.

FERRIS: 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.

[polka music plays] FERRIS: 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.

[polka music plays] MAN ON LOUDSPEAKER: Environmental control, ready.

MAN: Roger.

KOHLHASE: 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.

SPEAKER OVER TANNOY: We have just had a report from John Casani, the Voyager project manager, that we'll be able to count down at 10:25.

[gentle guitar music] NARRATOR: After five years of planning, the assembly of the spacecraft's 65,000 parts and untold mathematical calculations, it all came down to this.

[gentle guitar music] SPEAKER: Five, four, three, two, one.

We have ignition and we have lift-off.

LOCATELL: You see those solids ignite, and you are really not prepared for what's about to occur.

[gentle guitar music] The sound waves then catch up and then this forceful shaking, the body is actually moved in resonance with this energy, shaking it, right.

[audio of rocket taking off] LOMBERG: 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.

LINDA SPILKER: 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.

[atmospheric guitar music] DRAKE: 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.

[audio of crowd cheering and clapping] LOCATELL: There were outbursts of joy.

We were on our way!

CASANI: And then we launched it, and then other things went crazy.

[piano music] [radio noises] The spacecraft began to do things that we had no expectation that it would have done.

STONE: 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.

CASANI: 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.

HANSEN-KOHARCHECK: Us poor people on Earth, we're like what is it doing?

CASANI: 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.

LINICK: 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.

BELL: 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?

LOCATELL: That was a cliff hanger.

That was the end of the mission.

It could have been the end of the mission.

HANSEN-KOHARCHECK: Fortunately, the person who had written that code was able to say this is OK, it's doing this, it tried that, it's doing this, it tried that and calm everyone else down.

[bird sounds] The limits were set simply too tight.

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

[bird sounds] NARRATOR: 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.

SPEAKER: Centaur 6, Titan Centaur 6 has lifted off at 8:56 from here at the Cape Canaveral Air Force Station... KOHLHASE: We're thinking everything's OK, and then we begin to hear that something wasn't right.

CASANI: 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.

STONE: And so, the upper stage which was a Centaur-- liquid hydrogen and oxygen stage-- had to make up for that.

CASANI: 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.

KOHLHASE: 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.

CASANI: 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.

[laughs] [music: Gallagher & Lyle "Breakaway"] I watch the distant lights go down the runway Disappear into the evening sky Oh, you know I'm with you on your journey Never could say goodbye LOCATELL: 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.

[music: Gallagher & Lyle "Breakaway"] Though I won't stop you, I don't want you to Break away Fly across your ocean Break away Time has come for you Break away Fly across your ocean Break away Time has come [radio signals and white noise] NARRATOR: 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.

SODERBLOM: 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.

[music: classical music] [music: classical music] LAWRENCE KRAUSS: 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.

[classical string melody] NARRATOR: In January 1979, Voyager 1 was coming up on its first planetary encounter, and Voyager 2 was four months behind.

[classical string melody] SODERBLOM: It seems like time really flew.

SMITH: 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.

[laughs] STONE: 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.

[piano music] [piano music] TERRILE: The encounters, they creep up on you.

LINICK: When we were approaching, every picture was the greatest picture ever taken of Jupiter.

HANSEN-KOHARCHECK: 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.

BELL: Incredibly strange and beautiful, and now by Voyager revealed in all of its splendor.

TERRILE: 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.

JOURNALIST: Would someone care to speculate what you would say to Galileo Galilei if he walked into the room today?

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

[laughter] STONE: I think Galileo... STONE: 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.

ANDREW INGERSOLL: 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.

INGERSOLL: Let me first modify your statement, not that it was wrong ... INGERSOLL: 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.

SMITH: 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.

[low dramatic electronic rhythm music] INGERSOLL: 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.

SMITH: It was swallowing up clouds and spitting out others.

We knew that it was a vortex, but to see it in action... NARRATOR: Another feature of Jupiter's dynamic environment posed a great danger to Voyager.

Powerful radiation might destroy the spacecraft's electronics.

BELL: Every day you're wondering did we build the spacecraft well enough?

Did we anticipate all the possible things that could go wrong?

[low dramatic electronic rhythm music] BELL: 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.

LOCATELL: 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?

[radiation sounds Voyager recorded at Jupiter] NARRATOR: Voyager survived the onslaught and went on to record signals that led to a discovery.

DON GURNETT: 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.

[whistling frequency sounds] Whistlers.

These things that go [whistling sound], 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.

NARRATOR: The two Voyagers were poised to study Jupiter's little known moons.

[background music: fast strings with slow piano chords] [high pitched radio noises] Having picked up 36,000 miles an hour from Jupiter's gravity assist, the spacecraft were now traveling fast.

[background music: fast strings with slow piano chords] SODERBLOM: When you're on a flyby mission, there ain't no second chance.

KOHLHASE: 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.

SODERBLOM: 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.

NARRATOR: Every crater lasts for eons because no forces were present to resculpt the surface.

The first two moons were dormant worlds.

SODERBLOM: And then as we went into the inner two... KOHLHASE: 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.

BELL: 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.

SPILKER: And then of course, you know, kind of the showstopper for Voyager, we get to Io.

TERRILE: Io, of course, Io was the star of the show and we didn't learn that until after the encounter.

[soft piano music] INGERSOLL: 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.

LINDA MORABITO: I was on the mission as a mission navigator, and our job involved just looking back over the shoulder of the spacecraft to say, OK, one more picture of the realm of Jupiter, so it wasn't high-priority work.

SMITH: It was an optical navigation image, and Linda saw this strange thing on the limb.

MORABITO: 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.

[soft piano music] I found the very first evidence of active volcanism on a world beyond the Earth.

[soft piano music] STONE: 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.

NARRATOR: 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.

SODERBLOM: 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.

[laughter] SODERBLOM: The flyby is basically a week-long affair that's 24 hours a day.

It's intense.

ANNOUNCER: There will be a Voyager report in 30 seconds.

[electric guitar music] BELL: 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?

[heavy guitar music] TERRILE: 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.

[heavy guitar music] INGERSOLL: 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.

[heavy guitar music] HANSEN-KOHARCHECK: It was just way too exciting to...to sleep.

[heavy guitar music] [heavy guitar music ends and fades out] NARRATOR: 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.

HANSEN-KOHARCHECK: 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."

[atmospheric piano music] TERRILE: 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.

[electronic version of atmospheric motif] NARRATOR: 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.

[atmospheric music on strings] [atmospheric rhythmic music] 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.

[atmospheric rhythmic music] NICK SAGAN: 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.

[recordings of voices with rock music plays] JANET STERNBERG: 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.

NICK SAGAN: 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?

[tape rewinding] SAGAN AS A CHILD: Hello from the children of planet Earth.

NICK SAGAN: "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, OK, 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.

[greetings in various languages] [greetings in various languages] KOHLHASE: 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.

HAMMEL: 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.

[atmospheric guitar music] PORCO: 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.

NARRATOR: But the chance that an intelligent alien might encounter Voyager also hinges on another factor-- the sheer vastness of space.

SODERBLOM: The bigger you think space is, the less probable it is you're going to find them because they're needles in infinite haystacks.

KRAUSS: 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.

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

BAGENAL: 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.

BELL: The distances are almost unfathomable.

These were the fastest spacecraft that had ever been built and launched and flown, and they're travelling 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.

[music playing] HAMMEL: I'd like to know the answer, are we alone?

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

[music playing] FERRIS: The big division with extraterrestrial life is not space, it's time.

[music playing] KRAUSS: 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.

NICK SAGAN: 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?

[music playing] NARRATOR: In the fall of 1980, Voyager got its first close views of the planet Saturn.

[light piano music plays] SMITH: 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?

SPILKER: 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.

BELL: 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.

PORCO: We get there and we find that it's a blizzard of features throughout the rings, and it got very complex.

[guitar music] PORCO: 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.

SMITH: 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.

[electric guitar music] [electric guitar music] CARL SAGAN: 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.

CASANI: We had both spacecraft programmed to do identical missions at Saturn, and that was the prime mission and it involved Titan.

BELL: 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.

KOHLHASE: 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.

TERRILE: 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.

STONE: Voyager 2 would have done exactly that same thing if Voyager 1 had failed, we would have gone like this, no more planets.

KOHLHASE: That would have been really tough.

You gonna try for Titan again and give up two other worlds-- Uranus and Neptune?

BELL: So there was a lot of pressure on Voyager 1.

SODERBLOM: Mostly what we looked at was a giant ball of brown smog with some sort of electric blue hazes above it.

INGERSOLL: With the Voyager camera, you couldn't see through the clouds and haze.

[radio chatter] 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.

NARRATOR: Voyager 1 revealed a world at nearly 300 degrees below zero Fahrenheit that might have lakes of liquid methane under its smoggy atmosphere.

STONE: Voyager 1 had succeeded.

And shortly after that, NASA Headquarters agreed that we should continue with Voyager 2 on its Uranus trajectory.

NARRATOR: 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.

[music playing] BELL: 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.

[machines beeping] TERRILE: Something happened right around ring-plane crossing, and the images that were coming back were blank.

BELL: People thought maybe it crashed into the rings of Saturn.

Is this it, is it dead?

SPEAKER: OK. Ladies and gentlemen, we can start the briefing.

[tapping microphone] SPEAKER: I wanted to make a very brief statement.

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

AL HIBBS: The spacecraft has a problem.

The scan platform operating mechanism is not operating properly.

SPEAKER: 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.

SODERBLOM: A frozen scan platform could be a fatal, crippling event.

SMITH: Yeah, that was the darkest, the darkest day of the whole mission.

SPEAKER: There is circumstantial evidence... SMITH: I came into the auditorium, and there was just gloom on everybody's face.

SPEAKER: You're beginning to speculate.

SMITH: I quickly learned what had happened.

The scan platform had frozen.

SMITH: 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.

SMITH: 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... [electronic inquisitive music] SPEAKER: So, we've analyzed the slew data.

HANSEN-KOHARCHECK: It took a couple of days while the engineering team went to work diagnosing the problem.

SPEAKER: We are going to command an azimuth slew and an elevation slew to the Saturn position... STONE: 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 (makes turning noise).

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.

SMITH: It was frozen sort of like a car stuck in the, stuck in the snow.

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

SODERBLOM: It was freed up and back came the spacecraft and back came the imaging system, and there was Saturn on exit.

SMITH: [laughing] Yeah.

["Us & Them," Pink Floyd] TERRILE: 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.

["Us & Them," Pink Floyd] Us and them And after all we're only ordinary men... SODERBLOM: We felt like we were there.

Nobody even thought about it.

Voyager was part of us.

We... Me and you... PORCO: 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?

Forward!

He cried from the rear and the front rank died And the general sat, and the lines... NARRATOR: In the grooves of the Golden Record was another gift from us to them.

[guitar music] DRAKE: 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.

LOMBERG: 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.

[guitar music] DRAKE: 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.

NARRATOR: For Voyager, NASA decided to play it safe.

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

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

STONE: 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.

SMITH: 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.

[piano music] HANSEN-KOHARCHECK: Once we got beyond Saturn, essentially the engineers threw out the rulebook and said how are we going to make this work?

How are we going to take pictures of planets this far from the sun?

[piano music] BELL: 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.

SODERBLOM: We had all of the rich set of goodies from Jupiter and from Saturn, but Uranus was...was unknown.

[xylophone music] NARRATOR: In January 1986, Voyager 2 closed in on Uranus.

It would be by far the most remote planetary encounter ever attempted.

[xylophone music] TERRILE: It was like taking something that was almost fictional, almost mythological, and then seeing it as a real object.

BELL: 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.

STONE: Well, just about two minutes ago, Voyager 2 passed through its closest approach to Uranus.

[applause] SMITH: The new ring is right here.

Now, I don't... [laughter] you're telling me you can't see it.

I can.

JOURNALIST: Dr. Soderblom, as you whizzed through your explanation, I couldn't put it all together, could you try that again?

SODERBLOM: Slower?

[laughter] JOURNALIST: Slower and a few more details.

SODERBLOM: I thought that was pretty slow.

[guitar and strings music] STONE: 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.

BAGENAL: 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... BAGENAL: 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.

HAMMEL: At that point in its orbit, the planet didn't look exciting, and part of that is Uranus itself, holding its secrets back.

SMITH: 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.

HAMMEL: Ah...poor Uranus.

[laughs] Poor Uranus.

[guitar and piano music] [guitar and piano music] TERRILE: The big stars of the Uranus encounter were actually the moons.

[guitar music] KOHLHASE: 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... [string music] It looked like a jumbled-up mess.

[string music] HAMMEL: This moon looked like it had been ripped to pieces and then just sort of shoved back together again.

SMITH: Whoa!

Come look at this.

SPILKER: Going up to the screen and pointing and saying, "did you...look at that, look at that."

HAMMEL: No...nobody was ready for Miranda.

SODERBLOM: 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.

NARRATOR: At Uranus, Voyager detected intense radiation belts and discovered two new rings and ten tiny moons.

BAGENAL: 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... VO IN ARCHIVE: We have main engines start... 4...3...2...1...and lift-off!

Lift off of the 25th space shuttle mission, and it has cleared the tower.

BAGENAL: ...and we thought, OK, great, we'll watch the shuttle launch and then we'll go to the press conference, but of course that was Challenger.

VO IN ARCHIVE: Engines throttling up.

Three engine now at 104%.

Challenger, go with throttle up.

Roger, go with throttle up.

[soft piano music] SPILKER: 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.

[soft piano music] SMITH: Well, what can you say?

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

VO IN ARCHIVE: Flight Throttle.

Go ahead.

RSO reports vehicle exploded.

Copy.

DODD: And then of course they showed replays and replays and replays over and over and over again.

MAN IN ARCHIVE: We have no downlink.

OK, everybody, just stay off the telephones.

Make sure you maintain all your data, start pulling it together.

SPILKER: 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.

RONALD REAGAN: 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.

[sad string music plays] DODD: During these closest approach time periods, we would have hundreds of reporters come to JPL, and when the Challenger exploded, everybody just left.

[nearly silent save for ring of unattended microphone] [piano music] KRAUSS: 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.

[piano music] [traffic] [machines beeping] STONE: Finally at Neptune, Voyager has begun the last of a decade's worth of encounters with the outer planets.

BELL: 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.

BAGENAL: If we take the Earth being one astronomical unit from the sun, or AU for short.

Neptune is 30 times that distance.

STONE: 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.

VLA RADIO CONTROL: Copy, we're ready to run that observation.

STONE: 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.

BELL: 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.

[light keyboard music] NARRATOR: 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.

[music playing] HANSEN-KOHARCHECK: 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!

HAMMEL: 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.

BAGENAL: 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.

HAMMEL: 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.

[electric guitar music] INGERSOLL: 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, OK, two weeks from now, this storm is going to be right here and it usually was.

[electric guitar music] BAGENAL: 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.

TERRILE: 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.

SMITH: 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.

CROWD: Oh dear!

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

[laughter] KOHLHASE: We knew at Neptune we wanted a close flyby of Triton, which was a huge world around Neptune.

SODERBLOM: 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.

BELL: 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.

SODERBLOM: 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.

BELL: 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.

[atmospheric suspenseful music] 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... [atmospheric suspenseful music] TERRILE: 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.

SODERBLOM: 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.

BELL: 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.

SODERBLOM: 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.

[atmospheric suspenseful music] SODERBLOM: And I said holy moly, and so we knew what we had.

[music playing] [music playing] BAGENAL: These plumes.

Black geysers spewing out this stuff.

HAMMEL: The plumes extending out of the surface for like kilometers.

TERRILE: We were seeing eruptions on a world which should have been just a frozen cinder.

The last place we would have expected to see further dynamics, further eruptions was at a moon this remote in the solar system.

SODERBLOM: Just because an idea's crazy, it's not necessarily wrong.

CROWD: [laughter] NARRATOR: 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.

SPILKER: 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.

HANSEN-KOHARCHECK: 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.

[piano music] BELL: 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 port of call, the last thing we'll see in our solar system is now behind us.

[piano music] SMITH: 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.

[applause] [piano music] SMITH: The way I looked at it was gee, we did something really great.

Very, very successful mission.

SODERBLOM: A little weepy.

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

SPEAKER: We have ignition and we have lift-off.

[piano music] SODERBLOM: Years of intense effort.

It was the end of a sentimental journey.

[piano music] KOHLHASE: We did it.

We pulled it off, and that's important.

It is.

[music: "Johnny B. Goode" by Chuck Berry] Deep down in Lousiana close to New Orleans Way back up in the woods among the evergreens There stood a log cabin made of earth and wood Where lived a country boy named Johnny B. Goode HANSEN-KOHARCHECK: We had a big party at JPL, Chuck Berry was there, so that was a good send-off for Voyager.

CHUCK BERRY: Go, go Go, Johnny, go, go Go, Johnny, go, go Go, Johnny, go, go Go, Johnny, go, go Johnny B. Goode [music ends] DODD: Rockstar moment and sail on Voyager.

CARL SAGAN: And I'm going to go get some sleep or maybe I'll do a little more dancing...

Thank you very much, Lou?

[clapping] BELL: 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.

PORCO: 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.

SMITH: Absolutely zero science in it.

Absolutely none.

NARRATOR: 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.

[music playing] HANSEN-KOHARCHECK: 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.

[laughs] STONE: And so this is a different kind of milestone than the scientific milestones we've had.

One that is really symbolic... PORCO: 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.

CARL SAGAN: 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.

["Eclipse" by Pink Floyd begins to play] All that you touch And all that you see All that you taste All you feel And all that you love All that you hate All you distrust All you save And all you create And all you destroy And all that you do And all that you say And all that you eat And everyone you meet And all that you slight And everyone you fight And all that is now And all that is gone And all that's to come and everything under the sun is in tune but the sun is eclipsed by the moon NARRATOR: 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 travelled region between the stars that Voyager and its Golden Record will have a chance of being discovered.

KRIMIGIS: 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.

[inquisitive uplifting music] BELL: 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?

NARRATOR: 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.

DON GURNETT: We kept going and years went by and years went by and we don't detect the interstellar medium.

[music continues] BELL: 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.

[violin music] VO IN ARCHIVE: NASA says that Voyager 1 has become the first man-made object to reach interstellar space, the cold dark region between stars.

OBAMA IN ARCHIVE: And we've slipped the outermost grasp of our solar system with Voyager 1, the first human-made object to venture into interstellar space.

STONE: 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.

PORCO: It was like humanity had just become an interstellar species.

It was like knocking on eternity's door.

STERNBERG: 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.

[splashing noise] LOCATELL: 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!

NICK SAGAN: 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.

FERRIS: 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.

BELL: 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.

NICK SAGAN: Because there's no proof that there's anything that Voyager's ever going to encounter, ultimately, it's a story about us.

LOMBERG: 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.

SODERBLOM: There is never going to be another mission like it.

It was the first and last of its own kind.

KRAUSS: 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.

LOCATELL: 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.

[guitar/xylophone music] HANSEN-KOHARCHECK: 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.

[contemporary guitar interpretation of "Johnny B. Goode" plays over credits] [music continues] [music continues] [music continues]