The Farthest: Voyager's Interstellar Journey

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0:00:08 > 0:00:13# I'm wishing on a star

0:00:13 > 0:00:17# To follow where you are

0:00:18 > 0:00:23# I'm wishing on a dream

0:00:23 > 0:00:28# To follow what it means

0:00:28 > 0:00:31# And I wish on all the rainbows... #

0:00:31 > 0:00:35When it was just recently announced that Voyager 1 was in interstellar

0:00:35 > 0:00:39space, it was like humanity had just become an interstellar species,

0:00:39 > 0:00:41knocking on eternity's door.

0:00:44 > 0:00:47Voyager's on the other side of the solar system and it's billions and

0:00:47 > 0:00:50billions of miles from the nearest other human-made object.

0:00:55 > 0:00:57Voyager made it.

0:00:57 > 0:00:59Accomplished something no-one dreamed it could do.

0:01:01 > 0:01:03Every second, it goes to another

0:01:03 > 0:01:06place where we have never been before.

0:01:06 > 0:01:08It's on an escape trajectory.

0:01:08 > 0:01:09It's not coming back.

0:01:09 > 0:01:11It's just going to keep going

0:01:11 > 0:01:15forever and ever out into empty, empty space.

0:01:15 > 0:01:16Voyager takes the cake.

0:01:16 > 0:01:18It's the most audacious mission.

0:01:18 > 0:01:22I mean, who'd have thought that we'd actually be able to do that in 1977?

0:01:22 > 0:01:25# I'm wishing on a star... #

0:01:37 > 0:01:39We knew a little because you can

0:01:39 > 0:01:41observe from the Earth with telescopes.

0:01:43 > 0:01:45It was big.

0:01:45 > 0:01:48No, er, let's see, what did we know?

0:01:50 > 0:01:52We knew they were all gas giants,

0:01:52 > 0:01:55mostly made up of hydrogen and helium and some methane on the outer

0:01:55 > 0:01:59- planets.- We knew that there were winds on Jupiter.

0:01:59 > 0:02:01We knew about the great red spot on Jupiter.

0:02:01 > 0:02:03We knew that there was trapped radiation.

0:02:03 > 0:02:05So we knew there was a magnetic field.

0:02:05 > 0:02:08We knew, for example, at Jupiter, that there were four moons.

0:02:08 > 0:02:11Io, Europa, Ganymede and Callisto.

0:02:11 > 0:02:15That's what convinced Galileo that Copernicus was right and that the

0:02:15 > 0:02:18sun is the centre of the solar system.

0:02:18 > 0:02:22For Saturn, we knew about the rings and we knew about the major

0:02:22 > 0:02:25satellites, but hardly anything more than that,

0:02:25 > 0:02:28and it was all very fuzzy.

0:02:28 > 0:02:32And the same was true for Uranus and Neptune. They're very far away.

0:02:32 > 0:02:36I had been staring at these planets through some of the best telescopes

0:02:36 > 0:02:41on Earth, and yet all I could see was fuzzy blobs.

0:02:41 > 0:02:47Uranus was a small, blueish-green dot in the telescope and Neptune was

0:02:47 > 0:02:50an even smaller blueish dot, and that's all.

0:02:50 > 0:02:52Astronomers had worked pretty hard

0:02:52 > 0:02:54to know what the physical make-up was.

0:02:54 > 0:02:56There were some basic characteristics,

0:02:56 > 0:03:00but their real nature, we had none of that. Just little glimpses.

0:03:02 > 0:03:05There's theory, but then there's unknowns,

0:03:05 > 0:03:07and we're researching the unknowns.

0:03:09 > 0:03:12Human beings are a curious bunch.

0:03:12 > 0:03:14We want to know what's around that next bend in the road.

0:03:16 > 0:03:18This desire to explore conveys an

0:03:18 > 0:03:21evolutionary advantage, and I think there

0:03:21 > 0:03:25is a feeling that our survival as a species is going to depend on our

0:03:25 > 0:03:29learning how to live on other worlds.

0:03:29 > 0:03:32It's a very human thing to ask questions.

0:03:32 > 0:03:36It's a very childlike thing to ask a million questions.

0:03:36 > 0:03:38And some of us never grow up.

0:03:41 > 0:03:45One of the key things that made this mission possible was gravity assist.

0:03:45 > 0:03:49That is when you fly by Jupiter, you turn the corner and you take a

0:03:49 > 0:03:52little bit of Jupiter's orbital speed with you, like a slingshot.

0:03:52 > 0:03:56So you better make sure Saturn's in the right place.

0:03:56 > 0:04:00We were very fortunate that we had an alignment.

0:04:00 > 0:04:04Jupiter, Saturn, Uranus, and Neptune would all line up.

0:04:04 > 0:04:05It would go Jupiter, boom.

0:04:05 > 0:04:09Saturn, boom. Uranus, boom. Neptune, boom.

0:04:09 > 0:04:12The planets had to be lined up in just the right way to

0:04:12 > 0:04:14allow one spacecraft to do that.

0:04:14 > 0:04:17And that lining up only occurs rarely.

0:04:17 > 0:04:21That only happens once, like, once every 100, more than 100 years.

0:04:21 > 0:04:23175 years, something like that.

0:04:23 > 0:04:25Once every 176 years.

0:04:25 > 0:04:30It was named the Outer Planets Grand Tour and the cost of the mission was

0:04:30 > 0:04:33estimated to be in excess of a billion dollars.

0:04:35 > 0:04:37The Nasa administrator went to the

0:04:37 > 0:04:40President and he said the last time the

0:04:40 > 0:04:42planets were lined up like that,

0:04:42 > 0:04:47President Jefferson was sitting at your desk, and he blew it.

0:04:47 > 0:04:51So Mr Nixon laughed and he said, "Oh, all right, just do two."

0:04:53 > 0:04:56So only two planets and, of course,

0:04:56 > 0:05:00the price tag consequently was substantially less.

0:05:08 > 0:05:11The mission's success was one spacecraft past Saturn.

0:05:13 > 0:05:15But we knew right from the get-go

0:05:15 > 0:05:18that we were going to try as hard as we

0:05:18 > 0:05:21could to extend the mission to go to Uranus and Neptune.

0:05:21 > 0:05:24We designed that in from the beginning.

0:05:24 > 0:05:26We knew that we were endowing Voyager

0:05:26 > 0:05:29with the option if the chance was there to use it.

0:05:46 > 0:05:48We didn't want to build anything

0:05:48 > 0:05:50into the design that would've prevented

0:05:50 > 0:05:54us from going further, so it was a mission within a mission, yeah.

0:06:05 > 0:06:08The Golden Record really is the kind of heartbeat of the ship itself.

0:06:08 > 0:06:11The reason why it's going there is certainly exploring,

0:06:11 > 0:06:13but it's the lifeblood, is that record.

0:06:13 > 0:06:16When do you expect someone to find this record out there?

0:06:16 > 0:06:18Is there something out there?

0:06:18 > 0:06:21Well, nobody knows. One of the great unsolved questions

0:06:21 > 0:06:22is whether we're alone or...

0:06:22 > 0:06:25Carl Sagan has become probably the best-known scientist of

0:06:25 > 0:06:27the late 20th century.

0:06:27 > 0:06:31He played a key role in many of the Nasa missions to the planets,

0:06:31 > 0:06:33including the Voyager one.

0:06:33 > 0:06:37But he also was the astronomer who, as much as any one person,

0:06:37 > 0:06:40made the study of extraterrestrial life credible.

0:06:40 > 0:06:44If they be inhabited, what a scope for misery and folly.

0:06:45 > 0:06:49If they be not inhabited, what a waste of space.

0:06:49 > 0:06:51Pioneer 10 and 11 spacecraft,

0:06:51 > 0:06:54they had some line drawings of a male and female form,

0:06:54 > 0:06:57and it caused a lot of commotion, but I thought that was great.

0:06:57 > 0:07:01And I called him up and said, "Hey, would you be willing to undertake

0:07:01 > 0:07:03"to come up with something for us to put on the Voyager spacecraft?"

0:07:03 > 0:07:06And he says, "Yes, sure."

0:07:06 > 0:07:08They'd figured, don't let this opportunity pass.

0:07:08 > 0:07:10You're going to throw a message in a bottle into the ocean -

0:07:10 > 0:07:12put a message in it. And so they

0:07:12 > 0:07:15decided to put time capsules in those bottles.

0:07:15 > 0:07:18And at first, Carl thought they'd simply do another plaque,

0:07:18 > 0:07:22but Frank Drake, he came up with the idea that for the same amount of

0:07:22 > 0:07:25weight and space you could send a phonograph record.

0:07:25 > 0:07:29The only difference is it's on metal, so it will last a long time.

0:07:31 > 0:07:33The people who actually did the

0:07:33 > 0:07:35science part of Voyager are always jealous

0:07:35 > 0:07:38and mad because the Golden Record gets more attention than all the

0:07:38 > 0:07:39wonderful things they did,

0:07:39 > 0:07:42exploring the outer planets of the

0:07:42 > 0:07:44solar system except Pluto and all that.

0:07:44 > 0:07:46But the main attention goes to the Golden Record.

0:07:48 > 0:07:51Because of the aura that surrounds anything to do with extraterrestrial

0:07:51 > 0:07:53intelligent life,

0:07:53 > 0:07:56any kind of effort to contact extraterrestrial life

0:07:56 > 0:07:58is more fascinating than knowing the

0:07:58 > 0:08:02chemical make-up of a mineral on Mars or something.

0:08:02 > 0:08:04One of the first questions a lot of people ask is,

0:08:04 > 0:08:06"Well, they'll never figure out how to play it."

0:08:06 > 0:08:09And, in fact, we included a cartridge and stylus

0:08:09 > 0:08:11in the package with the record,

0:08:11 > 0:08:15and the drawing on the cover of the record shows the method by which the

0:08:15 > 0:08:17stylus is to be placed on the record.

0:08:19 > 0:08:22Maybe what's written on it will seem like kindergarten scribbles to them,

0:08:22 > 0:08:25but they should be able to figure it out.

0:08:25 > 0:08:28If they've got some smart minds, or whatever's in their heads -

0:08:28 > 0:08:30if they even have heads.

0:08:30 > 0:08:34What I find interesting is, to protect it from the dust

0:08:34 > 0:08:38and tiny particles of the journey, they put a cover over it,

0:08:38 > 0:08:44and on the cover was engraved the location of Earth, our solar system,

0:08:44 > 0:08:48in terms of its direction from different pulsars.

0:08:48 > 0:08:50A lot of people said, "Well, why would you do that?"

0:08:50 > 0:08:52I said, "What do you mean?" And they said,

0:08:52 > 0:08:54"Well, why would you announce where you are,

0:08:54 > 0:08:57"because there are aliens out there that probably raid planets and use

0:08:57 > 0:08:59"them for food or eat the people or make them into slavery,

0:08:59 > 0:09:02"and if they find that their technology is probably more advanced

0:09:02 > 0:09:04"than ours, they'll come here and destroy us,

0:09:04 > 0:09:06"so why would you do something like that?"

0:09:06 > 0:09:08So if somebody did find it, they would be thinking that way,

0:09:08 > 0:09:10and they'd say, "Why would these

0:09:10 > 0:09:12"people expose themselves to our voracious appetite?"

0:09:12 > 0:09:14They must be very altruistic, you know?

0:09:18 > 0:09:21The chance that advanced intelligence

0:09:21 > 0:09:23beyond us would detect -

0:09:23 > 0:09:28"Oh, hey, there's a radiating body coming into our area.

0:09:28 > 0:09:32"Let's go out and find out what this bottle in the ocean,

0:09:32 > 0:09:34"what message it might have."

0:09:34 > 0:09:36Now, is that a grand mystery?

0:09:38 > 0:09:39Whoa.

0:09:40 > 0:09:43Well, that brings up the whole question -

0:09:43 > 0:09:44is there anybody out there?

0:09:46 > 0:09:49Listen, there are,

0:09:49 > 0:09:53give or take, 200 billion stars in the Milky Way galaxy.

0:09:53 > 0:09:56There are about 200 billion galaxies in the universe,

0:09:56 > 0:09:59or at least in the universe we know about.

0:09:59 > 0:10:04It's a pretty small spacecraft, and it's a pretty big universe.

0:10:04 > 0:10:10If you take a piece of sky the size of a soda straw,

0:10:10 > 0:10:12up there in the Big Dipper,

0:10:12 > 0:10:16in that tiny piece of what we thought was blank sky

0:10:16 > 0:10:18was thousands of galaxies,

0:10:18 > 0:10:23and each one of those galaxies is filled with billions of stars.

0:10:24 > 0:10:26That's just a soda straw,

0:10:26 > 0:10:30and now you imagine the whole sky filled with thousands upon thousands

0:10:30 > 0:10:31upon thousands of galaxies,

0:10:31 > 0:10:34each of which is billions and billions of stars.

0:10:34 > 0:10:37There's a lot of possibility out there.

0:10:40 > 0:10:43If you took a grain of sand and put it on a table,

0:10:43 > 0:10:45and if that were the size of the sun,

0:10:45 > 0:10:47then the Earth would be about an inch away,

0:10:47 > 0:10:49and it would be microscopic,

0:10:49 > 0:10:53and the entire solar system would fit on a table six feet across.

0:10:53 > 0:10:57Think about the next star. The next star would be another grain of sand.

0:10:57 > 0:11:00How far away from that solar system would you have to put that?

0:11:00 > 0:11:02And it turns out to be about seven and a half miles away.

0:11:04 > 0:11:06The distances are almost unfathomable.

0:11:07 > 0:11:09These were the fastest spacecraft

0:11:09 > 0:11:12that had ever been built and launched and flown,

0:11:12 > 0:11:17and they're travelling at ten miles per second.

0:11:17 > 0:11:19You wouldn't even see it, right?

0:11:19 > 0:11:21And yet, even at those

0:11:21 > 0:11:24unfathomable-by-Earth-standards speeds,

0:11:24 > 0:11:27it takes decades, decades,

0:11:27 > 0:11:30to get out there into the outer solar system.

0:11:30 > 0:11:32If you want to realise how empty our galaxy is,

0:11:32 > 0:11:34the nearest galaxy to our own is Andromeda.

0:11:34 > 0:11:36It's about two million light years away.

0:11:36 > 0:11:38It is on a collision course with us right now.

0:11:38 > 0:11:41And in five billion years, that galaxy's going to collide with our

0:11:41 > 0:11:44own, and you might say, "Oh, no, oh, no!" Well, it turns out

0:11:44 > 0:11:48space is... Even in our galaxy, it's mostly empty space.

0:11:48 > 0:11:49When our two galaxies collide,

0:11:49 > 0:11:53almost no stars will hit any other star.

0:11:53 > 0:11:56- It's mostly empty space.- There's just a lot of room out there.

0:11:56 > 0:11:58A lot of room.

0:11:58 > 0:12:02So this adventure for this little spacecraft is really just

0:12:02 > 0:12:06exploring the tiniest, closest neighbourhood,

0:12:06 > 0:12:08when you start thinking about cosmic scales.

0:12:19 > 0:12:22The spacecraft were built at the Jet Propulsion Laboratory.

0:12:22 > 0:12:25It's a federal research centre that's part of Caltech,

0:12:25 > 0:12:26and they build spacecraft.

0:12:28 > 0:12:30One of the things I just admire most

0:12:30 > 0:12:32about the engineers who built Voyager

0:12:32 > 0:12:34is that they're always thinking

0:12:34 > 0:12:36about the most improbable things happening.

0:12:36 > 0:12:39You know, you want to take those people on a camping trip with you,

0:12:39 > 0:12:41because they will think of everything.

0:12:41 > 0:12:43"Well, you've got to bring..." "What if these bugs come out?"

0:12:43 > 0:12:46"What if the tent gets flooded?" "What if we run out of gas?"

0:12:46 > 0:12:47"What if you can't start the fire?"

0:12:47 > 0:12:49You know. They're the "what if" people.

0:12:49 > 0:12:52And when you're sending something out into space,

0:12:52 > 0:12:55you can't go do a service call, you can't bring it back.

0:12:55 > 0:12:59So your "what if" list had better be, like, that long,

0:12:59 > 0:13:02or you're not going to be able to survive.

0:13:08 > 0:13:13These projects begin with a conceptualisation period.

0:13:13 > 0:13:16How feasible is it for us to do thus and so?

0:13:17 > 0:13:21We didn't know what the spacecraft was going to look like.

0:13:21 > 0:13:23How do we arrange the spacecraft?

0:13:23 > 0:13:27How do we take the communications system in this large,

0:13:27 > 0:13:3012-foot diameter fixed antenna

0:13:30 > 0:13:34and arrange it relative to the propulsion system?

0:13:34 > 0:13:38The spacecraft took on the dimension of being a child,

0:13:38 > 0:13:41and our design teams, you know, were like parents.

0:13:41 > 0:13:45This was actually a nurturing process,

0:13:45 > 0:13:48bringing that child, if you will,

0:13:48 > 0:13:51into reality.

0:13:52 > 0:13:55All spacecraft are made basically of the same things,

0:13:55 > 0:13:59silicon and aluminium. That's probably 95% of it.

0:13:59 > 0:14:02The spacecraft, of course, is quite primitive by modern-day standards.

0:14:02 > 0:14:04We have three computers onboard.

0:14:04 > 0:14:06Their total memory is about, oh,

0:14:06 > 0:14:10240,000 times less than in your smartphone.

0:14:10 > 0:14:131972 was when you had the technology freeze.

0:14:13 > 0:14:15Remember, we launched in '77,

0:14:15 > 0:14:17so you'd freeze technology several years earlier.

0:14:17 > 0:14:19And at the time, the biggest

0:14:19 > 0:14:21computers in the world were comparable to the

0:14:21 > 0:14:23kinds of things we have in our pockets today,

0:14:23 > 0:14:26and I'm not talking about a cellphone.

0:14:26 > 0:14:28I'm actually talking about a key fob.

0:14:28 > 0:14:30What's wrong with '70s technology?

0:14:30 > 0:14:33I mean, you're looking at me - I'm a '30s technology, right?

0:14:35 > 0:14:36I don't apologise for limitations

0:14:36 > 0:14:38that we were working with at the time.

0:14:38 > 0:14:42We milked the technology for what we could get from it.

0:14:43 > 0:14:46Voyager is about 800 kilograms.

0:14:46 > 0:14:48Its main antenna is 12 feet in diameter,

0:14:48 > 0:14:51which is the largest we could launch.

0:14:51 > 0:14:55There's this body, this ten-sided can called the Bus,

0:14:55 > 0:14:58and that's got all the electronics and computers.

0:14:58 > 0:15:01And it's got these arms and these appendages that stick out,

0:15:01 > 0:15:04and there's these feet that connected it to the rocket.

0:15:04 > 0:15:06And then a really long arm with a

0:15:06 > 0:15:08magnetic field sensor on it over here,

0:15:08 > 0:15:09and another arm over there with this

0:15:09 > 0:15:11plutonium power supply to give it its electricity.

0:15:11 > 0:15:14You can't keep that too close to the spacecraft because it'll

0:15:14 > 0:15:15radiate the spacecraft.

0:15:15 > 0:15:18And another arm with this device that had the cameras and other

0:15:18 > 0:15:21instruments on it that could point around, kind of like the eyes,

0:15:21 > 0:15:24and the big antenna was the ears.

0:15:24 > 0:15:27When everything is fully extended,

0:15:27 > 0:15:31it's comparable in size to sort of a small school bus.

0:15:31 > 0:15:33A strange-looking being for our planet,

0:15:33 > 0:15:35but perfectly happy in space.

0:15:35 > 0:15:39MUSIC: Symphony No. 5 in C minor, Opus 67 by Beethoven

0:16:03 > 0:16:06I became the producer of only one record in my career,

0:16:06 > 0:16:08and only two copies of it were made

0:16:08 > 0:16:10and they were both hurled off the Earth,

0:16:10 > 0:16:13so I don't know that's a credential or not.

0:16:13 > 0:16:16The launch window for Voyager was set.

0:16:16 > 0:16:18It had to do with an alignment of the outer planets.

0:16:18 > 0:16:22They sure as hell weren't going to wait for the record.

0:16:22 > 0:16:25We had six weeks to do it. That's what always draws the biggest gasp.

0:16:25 > 0:16:28Figure out a way to explain the world to aliens and, by the way,

0:16:28 > 0:16:30it has to be finished in six weeks.

0:16:33 > 0:16:35We had two goals in making the Voyager record.

0:16:35 > 0:16:37We wanted the music to represent

0:16:37 > 0:16:40many different cultures around the world,

0:16:40 > 0:16:42and not just the culture of the

0:16:42 > 0:16:45society that had built and launched the spacecraft.

0:16:47 > 0:16:50The other criteria was we wanted it to be a good record.

0:16:51 > 0:16:54It's a very idiosyncratic message.

0:16:54 > 0:16:58It doesn't seem like something made by a committee. It's too quirky.

0:16:58 > 0:17:02MUSIC PLAYS: The Magic Flute, K. 620, Act II, Hell's Vengeance Boils In My Heart by Mozart

0:17:05 > 0:17:07If you listen to the Voyager record,

0:17:07 > 0:17:10it would be remarkable if you didn't hear some pieces of music

0:17:10 > 0:17:12that were quite unlike anything you'd heard before.

0:17:12 > 0:17:14The Japanese Shakuhachi piece,

0:17:14 > 0:17:16or the 16-year-old pygmy girl singing -

0:17:16 > 0:17:18it was called an initiation song,

0:17:18 > 0:17:20kind of puberty song -

0:17:20 > 0:17:25in the Ituri Forest of Africa is just unbelievably beautiful.

0:17:26 > 0:17:29It was a terrific, mind-expanding adventure.

0:17:33 > 0:17:36Always the criterion was that we were trying to describe our culture,

0:17:36 > 0:17:40and something we wanted very much was the music of the Beatles,

0:17:40 > 0:17:43and they said, "No way," and we said,

0:17:43 > 0:17:45"Well, this is all going in outer space.

0:17:45 > 0:17:48"It will never be heard on Earth."

0:17:48 > 0:17:51"No, we don't do it."

0:17:51 > 0:17:53They don't license for outer space.

0:17:56 > 0:17:58I would have loved to have had a Bob Dylan piece,

0:17:58 > 0:18:01but really there was only room for, at most,

0:18:01 > 0:18:04one contemporary rock piece.

0:18:05 > 0:18:08But, you know, you're up against Chuck Berry's Johnny B Goode,

0:18:08 > 0:18:11which Bob Dylan himself would admit is an awfully good single.

0:18:11 > 0:18:13It may be just four simple words,

0:18:13 > 0:18:15but it is the first positive proof

0:18:15 > 0:18:17that other intelligent beings inhabit the universe.

0:18:17 > 0:18:20What are the four words, Cocuwa?

0:18:20 > 0:18:22Send more Chuck Berry.

0:18:22 > 0:18:24LAUGHTER

0:18:24 > 0:18:27The world is full of fantastic music,

0:18:27 > 0:18:30and it goes without saying there's a lot more great music that's not on

0:18:30 > 0:18:32the Voyager record than there is on it.

0:18:32 > 0:18:35Which is a good thing, too. I mean, it'd be...

0:18:35 > 0:18:37Imagine living on planet that was so

0:18:37 > 0:18:40pathetic that it only had 90 minutes of decent music.

0:18:40 > 0:18:43- Flight control to launch enable. - Roger.

0:18:43 > 0:18:46The countdown will begin at ten minutes before midnight tonight.

0:18:46 > 0:18:48The journey, which will take the

0:18:48 > 0:18:50technology of Earth out of our solar system...

0:18:50 > 0:18:53When it was launched, it was, of course, all folded up.

0:18:53 > 0:18:54It was like origami.

0:18:56 > 0:19:02Here was this almost unexpected encapsulation.

0:19:02 > 0:19:05I mean, we knew that we were going to be encapsulated,

0:19:05 > 0:19:08but the emotional effect on that was kind of surprising.

0:19:08 > 0:19:11I noticed that in just looking around me.

0:19:12 > 0:19:19I realised that this was the last time any of us were going to see

0:19:19 > 0:19:22this spacecraft with eyes, and...

0:19:24 > 0:19:30..that's a fairly moving experience.

0:19:30 > 0:19:33- Environmental control ready.- Roger.

0:19:33 > 0:19:38We actually launched Voyager 2 first, and this gave the media...

0:19:40 > 0:19:44Drove them nuts. We launched Voyager 1 later,

0:19:44 > 0:19:47but it was launched on a faster trajectory,

0:19:47 > 0:19:50so it overtook Voyager 2 in December 1977.

0:19:50 > 0:19:55From that point on, Voyager 1 always got to the planet before Voyager 2,

0:19:55 > 0:19:58and the press was happy. They understood it.

0:19:58 > 0:20:01We have just had a report from John Casani, the

0:20:01 > 0:20:07Voyager project manager, that we'll be able to countdown at 10:25.

0:20:07 > 0:20:10They were launched on a Titan launch vehicle,

0:20:10 > 0:20:14which were intercontinental ballistic missiles for a long time,

0:20:14 > 0:20:16and some of them, as they were decommissioned,

0:20:16 > 0:20:20were turned into rockets to launch spacecraft out to the planets.

0:20:20 > 0:20:25Five, four, three, two, one.

0:20:25 > 0:20:29We have ignition, and we have liftoff.

0:20:29 > 0:20:31You see the solids ignite,

0:20:31 > 0:20:34and you're really not prepared for what's about to occur.

0:20:36 > 0:20:41The sound waves then catch up,

0:20:41 > 0:20:43and then this...

0:20:43 > 0:20:45forceful shaking -

0:20:45 > 0:20:50the body has actually moved in resonance with this energy,

0:20:50 > 0:20:53shaking it, right?

0:20:55 > 0:20:57We were sitting in bleachers,

0:20:57 > 0:21:00and they keep you pretty far from the launch vehicle because they can

0:21:00 > 0:21:02explode, and it's... Basically, it's a big bomb.

0:21:02 > 0:21:05So there was a little bit of holding your breath,

0:21:05 > 0:21:09and wanting to make sure you see it get that first little motion off the

0:21:09 > 0:21:12pad, starting into space.

0:21:12 > 0:21:14We were all thinking this thought - there it goes.

0:21:14 > 0:21:16And it's going to be out there to

0:21:16 > 0:21:18represent us for the next five billion years.

0:21:18 > 0:21:22I was a seven-year-old child watching it go and thinking, like,

0:21:22 > 0:21:24"Oh, I had some small thing to do on that."

0:21:24 > 0:21:29But no real significance, but it was like, "Oh, yeah, OK, goodbye."

0:21:31 > 0:21:34There were outbursts of joy.

0:21:35 > 0:21:37We were on our way.

0:21:39 > 0:21:42And then we launched it, and then other things went crazy.

0:21:44 > 0:21:46The spacecraft began to do things

0:21:46 > 0:21:50that we had no expectation that it would have done.

0:21:50 > 0:21:54Us poor people on Earth were like, "What is it doing?"

0:21:54 > 0:21:57As the launch vehicle leaves the launch pad, it has to roll through a

0:21:57 > 0:22:02certain angle to get to the right direction for departure.

0:22:02 > 0:22:05And the rate that it rolls at is a much higher rate than the spacecraft

0:22:05 > 0:22:07would never normally experience flying,

0:22:07 > 0:22:09and so the gyro hits the stops.

0:22:09 > 0:22:11Voyager was not in control of itself.

0:22:11 > 0:22:13It's just riding this big rocket,

0:22:13 > 0:22:16and that was shaking it in such a way that it thought it was failing,

0:22:16 > 0:22:18and so it started switching off various boxes,

0:22:18 > 0:22:21changing to the backup this, to the backup that,

0:22:21 > 0:22:23trying to figure out why all this stuff was happening.

0:22:23 > 0:22:26For a couple of days, it was a real nail-biter

0:22:26 > 0:22:29and people were asking us, "Have you lost the spacecraft?"

0:22:29 > 0:22:31And we would say, "We don't know for sure,"

0:22:31 > 0:22:33because we didn't know for sure.

0:22:33 > 0:22:36And the headline read, "Mutiny in Space."

0:22:36 > 0:22:39The Voyager spacecraft had decided it just didn't want to follow the

0:22:39 > 0:22:43instructions that its human controllers were giving it and it

0:22:43 > 0:22:45was going to do what it wanted to do.

0:22:45 > 0:22:49Fortunately, the person who had written that code was able to say,

0:22:49 > 0:22:51"This is OK - it's doing this, it tried that.

0:22:51 > 0:22:53"It's doing this, it tried that."

0:22:53 > 0:22:55And calm everyone else down.

0:22:58 > 0:23:02All the time it was doing that crazy stuff it was doing exactly what we

0:23:02 > 0:23:04had designed it to do all along.

0:23:04 > 0:23:06The limits were set simply too tight.

0:23:06 > 0:23:11It needed to be able to wiggle more and vibrate more.

0:23:13 > 0:23:16All of those things were solved for Voyager 1.

0:23:16 > 0:23:20When Voyager 1 lifted off, we're thinking everything's OK,

0:23:20 > 0:23:22and then we begin to hear this - we call it chatter -

0:23:22 > 0:23:24over the launch vehicle net

0:23:24 > 0:23:26that something wasn't right.

0:23:26 > 0:23:27I looked over at him and he looked

0:23:27 > 0:23:29like he was a little worried, you know,

0:23:29 > 0:23:31and I said, "What's the matter, Charlie?"

0:23:31 > 0:23:33And he says, "I don't know. I don't

0:23:33 > 0:23:35"think we're going to make it," you know.

0:23:35 > 0:23:37There was a leak in the propellant line,

0:23:37 > 0:23:39and we were losing propellant overboard.

0:23:39 > 0:23:40So while it was burning, propellant

0:23:40 > 0:23:42was escaping from the launch vehicle,

0:23:42 > 0:23:44and that's why its second stage

0:23:44 > 0:23:46never got to deliver its full thrust,

0:23:46 > 0:23:47because it ran out of fuel.

0:23:47 > 0:23:50And so the upper stage, which was a Centaur

0:23:50 > 0:23:54liquid hydrogen and oxygen stage, had to make up for that.

0:23:54 > 0:23:56And the Centaur is the stage that's doing the guidance,

0:23:56 > 0:24:00so the Centaur knows that it's not reaching the required velocity,

0:24:00 > 0:24:03because it has to burn longer to add more velocity.

0:24:03 > 0:24:08The Centaur had to use 1,200 pounds of extra propellant.

0:24:08 > 0:24:09Now we're all thinking,

0:24:09 > 0:24:11"Is it going to have enough left in

0:24:11 > 0:24:14"the tanks to make a normal injection?

0:24:14 > 0:24:15"Or is it going to run out of fuel?"

0:24:17 > 0:24:23Fortunately, it had three and a half seconds of thrusting left before it

0:24:23 > 0:24:25had run to fuel depletion.

0:24:25 > 0:24:26Three and a half seconds.

0:24:26 > 0:24:29So Voyager 1 just barely made it.

0:24:29 > 0:24:31It wouldn't have gotten enough

0:24:31 > 0:24:33velocity to get to Jupiter, you know,

0:24:33 > 0:24:35so instead of getting to Jupiter, you know,

0:24:35 > 0:24:38we'd have gotten almost to Jupiter and then it would come back towards

0:24:38 > 0:24:40the sun, which would not have been good.

0:24:40 > 0:24:45# I watch the distant lights go down the runway

0:24:45 > 0:24:50# Disappearing through the evening sky

0:24:50 > 0:24:55# Oh, you know I'm with you on your journey

0:24:55 > 0:24:58# Never could say goodbye... #

0:24:58 > 0:25:00And then, of course, you know,

0:25:00 > 0:25:04there's the thought that it's out of our hands.

0:25:04 > 0:25:09Now the major reason for this mission was about to unfold,

0:25:09 > 0:25:15that is the science, but our role as

0:25:15 > 0:25:20keepers, as progenitors,

0:25:20 > 0:25:23our role had been finished.

0:25:29 > 0:25:30That was moving.

0:25:30 > 0:25:36# Break away

0:25:36 > 0:25:40# Fly across your ocean

0:25:40 > 0:25:45# Break away

0:25:45 > 0:25:49# Time has come for you

0:25:49 > 0:25:54# Break away

0:25:54 > 0:25:58# Fly across your ocean

0:25:58 > 0:26:02# Break away

0:26:02 > 0:26:07# Time has come... #

0:26:07 > 0:26:10It's worth realising that a human life ago,

0:26:10 > 0:26:12less than 100 years ago, 87 years ago,

0:26:12 > 0:26:16the universe consisted of one galaxy, our Milky Way galaxy,

0:26:16 > 0:26:19in a static eternal universe, with eternal empty space.

0:26:19 > 0:26:21We didn't know about the other

0:26:21 > 0:26:24hundred billion galaxies a single human lifetime ago.

0:26:39 > 0:26:43You can never really imagine... You can try,

0:26:43 > 0:26:45but you can never really imagine

0:26:45 > 0:26:49what Mother Nature will actually have in store when you get there.

0:26:57 > 0:27:00It seems like time really flew.

0:27:02 > 0:27:05I don't think we really fully understood,

0:27:05 > 0:27:09before the first Jupiter encounter, just how intense it was going to be.

0:27:09 > 0:27:10No, we didn't.

0:27:12 > 0:27:14We found out.

0:27:16 > 0:27:21You start working on a mission in 1972, you launch in 1977.

0:27:21 > 0:27:23All of that, there's no science.

0:27:23 > 0:27:25It's all getting ready.

0:27:25 > 0:27:28And then, March '79, the flood.

0:27:43 > 0:27:46The encounters, they creep up on you.

0:27:48 > 0:27:50When we were approaching,

0:27:50 > 0:27:54every picture was the greatest picture ever taken of Jupiter.

0:27:54 > 0:27:57In the beginning, it would be just a little dot getting bigger on the

0:27:57 > 0:28:01screen every day, and as we would get closer and closer,

0:28:01 > 0:28:05the images became more dramatic.

0:28:05 > 0:28:07Incredibly strange and beautiful,

0:28:07 > 0:28:12and now, by Voyager, revealed in all of its splendour.

0:28:15 > 0:28:19Would someone care to speculate what you would say to Galileo Galilei if

0:28:19 > 0:28:21he walked into the room today?

0:28:22 > 0:28:25How are you able to live so long?

0:28:25 > 0:28:28LAUGHTER

0:28:30 > 0:28:32I think Galileo...

0:28:32 > 0:28:34Jupiter is more than ten times the diameter of Earth -

0:28:34 > 0:28:37it's huge. And it's mainly hydrogen and helium.

0:28:37 > 0:28:39There's no solid surface on these planets.

0:28:39 > 0:28:42These planets are liquid - gas and liquid - deep inside.

0:28:42 > 0:28:45The gas is compressed the further down you go,

0:28:45 > 0:28:47and it gets very hot indeed.

0:28:47 > 0:28:51And you would melt, vaporise in fact,

0:28:51 > 0:28:54if you tried to fly through Jupiter.

0:28:54 > 0:28:57Let me first modify your statement - not that it was wrong...

0:28:57 > 0:29:01The atmospheric scientists got long-range views,

0:29:01 > 0:29:03because we weren't looking at tiny moons,

0:29:03 > 0:29:06we were looking at the big planet.

0:29:06 > 0:29:11And so we could see things going on before the other groups could see

0:29:11 > 0:29:15things, and we were always the first to start shouting.

0:29:16 > 0:29:20Even to this day, we don't fly colour detectors.

0:29:20 > 0:29:24You get a much higher resolution image in black and white,

0:29:24 > 0:29:26and so when we want to make colour

0:29:26 > 0:29:28we take them through different filters

0:29:28 > 0:29:30and then on the ground you put it

0:29:30 > 0:29:32together and make a colour image out of it.

0:29:32 > 0:29:33That acceleration as you're

0:29:33 > 0:29:35approaching encounters is really something

0:29:35 > 0:29:37that becomes very, very exciting.

0:29:37 > 0:29:39We called it drinking out of a fire hose.

0:29:39 > 0:29:41You know, you're trying to take a little sip,

0:29:41 > 0:29:43and this torrent of data is coming out.

0:29:45 > 0:29:47You go to Jupiter and you have a

0:29:47 > 0:29:49storm that's been around for more than

0:29:49 > 0:29:52300 years. That's the great red spot.

0:29:52 > 0:29:54You could fit two or three Earths inside it.

0:29:55 > 0:29:57When Voyager started getting

0:29:57 > 0:30:00close-up images we realised that it was very active,

0:30:00 > 0:30:05and that deepened the mystery of how these big storms could even

0:30:05 > 0:30:08exist, with all this

0:30:08 > 0:30:10turbulence going on.

0:30:10 > 0:30:13It was swallowing up clouds and spitting out others.

0:30:13 > 0:30:17We knew that it was a vortex, but to see it in action...

0:30:21 > 0:30:24Every day, you're wondering, "Did we build the spacecraft well enough?

0:30:24 > 0:30:28"Did we anticipate all the possible things that could go wrong?"

0:30:33 > 0:30:36You're approaching this monster, essentially.

0:30:36 > 0:30:39This monster magnetic field, this monster radiation environment,

0:30:39 > 0:30:42on purpose, because you need to get close,

0:30:42 > 0:30:45because you want to see all the little moons and the clouds and the

0:30:45 > 0:30:48storms, and you want to slingshot on to Saturn.

0:30:48 > 0:30:50But you just don't know if you're going to survive.

0:30:50 > 0:30:52The thing gets fried, you lose the mission.

0:30:52 > 0:30:55Still out there physically intact probably,

0:30:55 > 0:30:58but unable to communicate with it - the mission's over.

0:30:58 > 0:31:01Two months before shipping to the Cape for launch,

0:31:01 > 0:31:07the scientists were predicting that the magnetic fields around Jupiter

0:31:07 > 0:31:11were intense enough that they would accelerate particles.

0:31:11 > 0:31:15Well, we were hearing initially 40,000 volts.

0:31:15 > 0:31:18That would be the end of our spacecraft.

0:31:18 > 0:31:22Cabling on these appendages were conductors that would take these

0:31:22 > 0:31:27destroying pulses and just feed them right into our systems and kill us.

0:31:27 > 0:31:29So we needed to ground everything.

0:31:30 > 0:31:34We didn't have time to go through the normal design reviews,

0:31:34 > 0:31:38so in order to get this protection done quickly enough,

0:31:38 > 0:31:40we did some things that were out of the ordinary,

0:31:40 > 0:31:42very out of the ordinary.

0:31:42 > 0:31:45I can remember asking one of the

0:31:45 > 0:31:48technicians to go out and buy aluminium foil.

0:31:48 > 0:31:51Normally our procurement of spacecraft

0:31:51 > 0:31:55hardware, supplies, materials,

0:31:55 > 0:31:59are a much more sophisticated process.

0:31:59 > 0:32:03We are all in bunny suits cutting continuous strips,

0:32:03 > 0:32:05cleaning them with alcohol,

0:32:05 > 0:32:07and then finally wrapping these on

0:32:07 > 0:32:10all of our exterior cabling but, yeah,

0:32:10 > 0:32:13same materials in your Christmas turkey.

0:32:15 > 0:32:17I don't think we created any shortage, per se.

0:32:17 > 0:32:21It may have been a local shortage in the local grocery store for a few

0:32:21 > 0:32:24days until they reordered, right?

0:32:24 > 0:32:26And now fast forward.

0:32:26 > 0:32:29You know, did we know whether we'd done enough?

0:32:38 > 0:32:41Amazingly, we heard all kinds of sounds.

0:32:41 > 0:32:43If you had the right kind of antennas on your ears,

0:32:43 > 0:32:45you could go out and hear what we record.

0:32:47 > 0:32:50Whistlers - whistlers mean lightning.

0:32:50 > 0:32:52That was the first detection of

0:32:52 > 0:32:55lightning on a planet other than Earth. Much more intense.

0:32:55 > 0:32:59There are lightning flashes at Jupiter that would go halfway from

0:32:59 > 0:33:02the East Coast of the United States to the West Coast,

0:33:02 > 0:33:06so it's fascinating what you hear in space.

0:33:10 > 0:33:14When you're on a flyby mission, there ain't no second chance.

0:33:14 > 0:33:17We were getting pictures - they were getting better and better,

0:33:17 > 0:33:21and you could begin to see detail, as these moons got bigger.

0:33:21 > 0:33:24You know, the dread you have is that you don't want to see a lot of

0:33:24 > 0:33:26worlds that look like Earth's moon.

0:33:26 > 0:33:28Let's face it - it's dull.

0:33:28 > 0:33:33Our mind's eye was, "Oh, yeah, we're going to see battered ice balls,

0:33:33 > 0:33:37"like the highlands of the moon, nothing but impact craters."

0:33:37 > 0:33:40When we saw Callisto, basically it's totally hammered, right?

0:33:40 > 0:33:42It's saturated with impact craters.

0:33:42 > 0:33:46Ganymede shows a lot of interesting grooves and ridges,

0:33:46 > 0:33:49but it's pretty blasted with impact craters.

0:33:49 > 0:33:51And then as we went into the inner two...

0:33:53 > 0:33:56You could not see craters on either one of them.

0:33:56 > 0:33:57Well, this was encouraging,

0:33:57 > 0:34:00because now we think maybe this

0:34:00 > 0:34:03mission is going to find a lot of diversity.

0:34:03 > 0:34:05Discovering this...

0:34:05 > 0:34:09billiard ball-smooth icy crust of Europa, with cracks in it,

0:34:09 > 0:34:11and what looked like plates of ice

0:34:11 > 0:34:14that might be moving relative to each other.

0:34:14 > 0:34:17The best explanation for that is that there's a thick ocean of

0:34:17 > 0:34:22liquid water, salty water, underneath that icy crust.

0:34:22 > 0:34:24More ocean water than on the entire Earth.

0:34:24 > 0:34:26Probably two or three times.

0:34:26 > 0:34:28It's the largest ocean in the solar system.

0:34:28 > 0:34:30And a moon around - going round Jupiter.

0:34:30 > 0:34:32And then, of course, kind of the

0:34:32 > 0:34:35show stopper for Voyager, we get to Io.

0:34:35 > 0:34:37Io, of course. Io was the star of the show,

0:34:37 > 0:34:41and we didn't learn that until after the encounter.

0:34:42 > 0:34:46Everyone had gone home, and Linda Morabito,

0:34:46 > 0:34:48an engineer whose job was to find

0:34:48 > 0:34:51out the positioning and the orbit of the

0:34:51 > 0:34:55spacecraft, noticed some bumps on images of Io.

0:34:55 > 0:34:59I was on the mission as a mission navigator,

0:34:59 > 0:35:02and our job involved just looking

0:35:02 > 0:35:05back over the shoulder of the spacecraft

0:35:05 > 0:35:09to say OK, one more picture of the realm of Jupiter.

0:35:09 > 0:35:12So it wasn't high-priority work.

0:35:12 > 0:35:15It was an optical navigation image,

0:35:15 > 0:35:19and Linda saw this strange thing on the limb.

0:35:19 > 0:35:22An enormous object emerged.

0:35:22 > 0:35:27Enormous. And the first thing I said to myself - "What is that?!"

0:35:27 > 0:35:31And I'm like, "It looks like another satellite

0:35:31 > 0:35:35"in the picture, emerging from behind Io."

0:35:35 > 0:35:39An object that size, at that range, at that distance,

0:35:39 > 0:35:43would have been seen from Earth. It was sufficiently large.

0:35:43 > 0:35:46I felt, with certainty - it was the only thing I knew -

0:35:46 > 0:35:49that I was seeing something that had never been seen before.

0:35:49 > 0:35:56This was an umbrella-shaped plume rising 250 kilometres

0:35:56 > 0:36:01above the surface of Io, with volcanic activity.

0:36:05 > 0:36:08I found the very first evidence of

0:36:08 > 0:36:12active volcanism on a world beyond Earth.

0:36:16 > 0:36:19It was so hard to believe that a little moon could have ten times

0:36:19 > 0:36:21the volcanic activity of Earth,

0:36:21 > 0:36:23which was the only known active volcanoes in the solar system,

0:36:23 > 0:36:26were here on Earth. And then there's Io.

0:36:26 > 0:36:30Suddenly we had realised this was a different journey we were on.

0:36:30 > 0:36:32I wanted to say one other thing.

0:36:32 > 0:36:34We've been saying that perhaps there's some funny way in which

0:36:34 > 0:36:36Jupiter gobbles up all the things

0:36:36 > 0:36:38that are coming in and doesn't let Io be hit by any.

0:36:38 > 0:36:41Well, we aimed a spacecraft and went very close,

0:36:41 > 0:36:44and had we missed, we would have made the first impact crater.

0:36:44 > 0:36:46LAUGHTER

0:36:46 > 0:36:53The flyby is basically a week-long affair that's 24 hours a day.

0:36:53 > 0:36:55It's intense.

0:36:55 > 0:36:58There will be a Voyager report in 30 seconds.

0:37:07 > 0:37:10Instant science, because there's going to be a press conference that

0:37:10 > 0:37:11night. This picture comes down,

0:37:11 > 0:37:13and you've got three hours to figure

0:37:13 > 0:37:16out what's going on and then tell the world about it.

0:37:16 > 0:37:18No pressure there, right?

0:37:19 > 0:37:22The confines of being a piece of biology got in the way of that.

0:37:22 > 0:37:24I mean, you got hungry, you got tired, you know,

0:37:24 > 0:37:26you had to go to the bathroom.

0:37:26 > 0:37:28I mean, you're going to miss something.

0:37:28 > 0:37:29But you don't want to miss anything,

0:37:29 > 0:37:32because every 48 seconds a new image would come down.

0:37:36 > 0:37:38No-one got any sleep during one of

0:37:38 > 0:37:42these flybys when the spacecraft would go zooming past.

0:37:42 > 0:37:45The photo labs were working day and night,

0:37:45 > 0:37:48and people were sleeping in their cars.

0:37:53 > 0:37:57It was just way too exciting to sleep.

0:38:24 > 0:38:27This is the first picture ever of Jupiter's ring.

0:38:33 > 0:38:35Jupiter was really just wonderful.

0:38:35 > 0:38:38It was just discovery after discovery.

0:38:41 > 0:38:43Jupiter was a game changer.

0:38:43 > 0:38:45Jupiter reset all the registers.

0:38:45 > 0:38:47Now we're really up for something.

0:38:47 > 0:38:49And to know that this was just the

0:38:49 > 0:38:51very, very beginning of this journey.

0:38:51 > 0:38:55If we're blown away by Jupiter, just wait until we get to Saturn.

0:38:59 > 0:39:02Voyager, to me, was Homeric.

0:39:02 > 0:39:07It was years of passing across the solar system from one planet to the

0:39:07 > 0:39:12other, and then it was a week or two of frenzied activity and discovery

0:39:12 > 0:39:14and conquest, and then it was, well,

0:39:14 > 0:39:16back in the boats, oars in the water,

0:39:16 > 0:39:18and then on to the next conquest.

0:39:29 > 0:39:33My father was Carl Sagan, and my mother is Linda Salzman Sagan,

0:39:33 > 0:39:35and she's writer and an artist,

0:39:35 > 0:39:38and she designed the iconic Pioneer plaque. She actually drew it,

0:39:38 > 0:39:40and she's the one who got all of the

0:39:40 > 0:39:43greetings for the Voyager Golden Record.

0:39:43 > 0:39:46I like to think of her that she kind of put together a choir of voices of

0:39:46 > 0:39:48greetings to the stars.

0:39:49 > 0:39:54OVERLAPPING VOICES IN VARIOUS LANGUAGES

0:39:57 > 0:39:58My parents wanted a child

0:39:58 > 0:40:03to have one of the voices, and they just came to me one day and said,

0:40:03 > 0:40:05"Nick, if you'd like to leave a message to aliens,

0:40:05 > 0:40:08"if they happen to exist, what would you like to say to them?"

0:40:11 > 0:40:15Hello from the children of planet Earth.

0:40:15 > 0:40:16Oh, "Hello from the children of planet Earth,"

0:40:16 > 0:40:19that's what I would say to aliens.

0:40:19 > 0:40:22They loved that, and said, "Great, let's record you."

0:40:23 > 0:40:25It's a bit of a blur.

0:40:25 > 0:40:27The only thing I know that I

0:40:27 > 0:40:29remember from that time is those knobs and

0:40:29 > 0:40:32the little recording level that goes into the red if you speak too much,

0:40:32 > 0:40:34'70s kind of...

0:40:34 > 0:40:37So, I remember that, and I remember watching the needle move as I spoke

0:40:37 > 0:40:40and seeing, like, where it... "Oh, that got close to the red,

0:40:40 > 0:40:43"but that actually didn't go into the red. OK, that's probably good."

0:40:43 > 0:40:45And that was that. And then I, you know,

0:40:45 > 0:40:48drank my apple juice and went back to my books.

0:40:49 > 0:40:53It was really not until considerably later that the enormity of what that

0:40:53 > 0:40:54meant actually hit me.

0:41:06 > 0:41:10The reason I was chosen was not because I'm something special.

0:41:10 > 0:41:13I happened to be there at the right time, at the right place,

0:41:13 > 0:41:16and people knew that I speak Arabic,

0:41:16 > 0:41:19- so I was lucky. - I said, "Why me?" They said,

0:41:19 > 0:41:23"Because you speak fluent Portuguese."

0:41:23 > 0:41:25I didn't get any instructions about

0:41:25 > 0:41:28what to say except that it needs to be short.

0:41:28 > 0:41:31The greetings to the universe are almost like proto tweets,

0:41:31 > 0:41:34the first tweets - keep it short, keep it simple.

0:41:41 > 0:41:45It's not like there's a rule book for what you should say when you're

0:41:45 > 0:41:46greeting the universe.

0:41:50 > 0:41:53Paz e felicidade todos.

0:41:53 > 0:41:56Which means peace and happiness to everybody.

0:41:56 > 0:42:01It seemed like a safe thing to say if you ran across some aliens,

0:42:01 > 0:42:05rather than saying, "Take me to your leader," or whatever.

0:42:11 > 0:42:16Because the equipment is cold, the spaceship is inanimate,

0:42:16 > 0:42:18even the record itself is metal,

0:42:18 > 0:42:24and I just wanted my voice to convey warmth and to make contact.

0:42:24 > 0:42:30SHE SPEAKS OWN LANGUAGE

0:42:30 > 0:42:33Greetings to our friends in the sky.

0:42:33 > 0:42:36We long to meet you someday.

0:42:40 > 0:42:44There is some piece of me that is a traveller on that ship.

0:42:44 > 0:42:48It's just gone, it's just going, it continues to go.

0:42:48 > 0:42:51It's going to keep going. When I'm long, long gone, it'll keep going.

0:42:51 > 0:42:53And it's like a little piece of magic.

0:42:53 > 0:42:56Hello from the children of planet Earth.

0:42:58 > 0:43:04# In your mind you have capacities you know

0:43:04 > 0:43:10# To telepath messages through the vast unknown

0:43:10 > 0:43:12# Please close your eyes

0:43:12 > 0:43:18# And concentrate with every thought you think

0:43:18 > 0:43:24# Upon the recitation we're about to sing

0:43:27 > 0:43:31# Calling occupants of interplanetary craft... #

0:43:31 > 0:43:34I'd like to know the answer - are we alone?

0:43:34 > 0:43:37I'd like to know the answer to that question.

0:43:37 > 0:43:39There has to be other civilisations.

0:43:39 > 0:43:42The numbers just compel it.

0:43:42 > 0:43:46It would be almost statistically impossible for there not to be

0:43:46 > 0:43:49other life forms and other life forms that have

0:43:49 > 0:43:52evolved to a state of intelligence and beyond.

0:43:52 > 0:43:55# Calling occupants of interplanetary craft... #

0:43:55 > 0:43:57I'll tell you, I think that intelligent life,

0:43:57 > 0:44:01if we can include ourselves in that categorisation,

0:44:01 > 0:44:04is so prevalent that I'll bet you, at this very instant,

0:44:04 > 0:44:08there are two people, probably one male and one female,

0:44:08 > 0:44:12having exactly the same conversation that you and I are having right now.

0:44:16 > 0:44:19They're probably trying to contact us at this very minute.

0:44:20 > 0:44:24I predict, passing through this room right now,

0:44:24 > 0:44:28radio messages that we could detect with equipment we could build

0:44:28 > 0:44:31if we knew where to aim that

0:44:31 > 0:44:35detector and what frequency to tune to.

0:44:35 > 0:44:40And it's right here in this room, and that's mind-boggling.

0:44:40 > 0:44:43You know, they're here, they're right in the room right now.

0:44:44 > 0:44:45The big division with

0:44:45 > 0:44:48extraterrestrial life is not space, it's time.

0:44:49 > 0:44:53It depends on how long civilisations last,

0:44:53 > 0:44:56because you've got to get them to overlap for us to communicate.

0:44:56 > 0:44:59In our galaxy, our sun is relatively young.

0:44:59 > 0:45:01The galaxy is about 12 billion years old.

0:45:01 > 0:45:02Our sun's 4.5 billion years old.

0:45:02 > 0:45:04There are many stars that are a lot older.

0:45:04 > 0:45:07Therefore, you could imagine some civilisation around such a star that

0:45:07 > 0:45:10might have watched our Earth form over the last four and a half

0:45:10 > 0:45:13billion years. Well, over that last four and a half billion years,

0:45:13 > 0:45:16the only evidence of intelligent life would have been in the last 50

0:45:16 > 0:45:17or 60 years, by watching Star Trek

0:45:17 > 0:45:20or I Love Lucy or whatever signals we sent out.

0:45:20 > 0:45:22So, even if someone told you, look at that star,

0:45:22 > 0:45:24and then look at the third rock from that star,

0:45:24 > 0:45:27and that's where you're going to find life, there's only a 50 year

0:45:27 > 0:45:29period over five billion years, almost,

0:45:29 > 0:45:32where you'd be able to find intelligent life.

0:45:32 > 0:45:34If we're alone, then we're truly unique,

0:45:34 > 0:45:37and how did that happen? And why us?

0:45:37 > 0:45:40And how are we so special and yet in such a kind of far-flung,

0:45:40 > 0:45:42humdrum part of the universe?

0:45:42 > 0:45:45And if we're not alone, how did we all get here,

0:45:45 > 0:45:48and can we learn about ourselves by these other groups out there?

0:45:48 > 0:45:50What are they like? And are they the

0:45:50 > 0:45:53creatures of our dreams or our nightmares?

0:45:53 > 0:45:55I think what's going to save us is

0:45:55 > 0:45:58that interstellar travel is much harder

0:45:58 > 0:46:02than we think, and we're safe for quite a long time from the aliens,

0:46:02 > 0:46:05cos they don't know how to travel very far either.

0:46:05 > 0:46:07We're all sort of stuck on the planets we've got.

0:46:17 > 0:46:20Jupiter to Saturn went just like that. It was really quick.

0:46:30 > 0:46:34We started off with images that were probably no better than what you can

0:46:34 > 0:46:37get from the ground, and then it keeps getting better and better and

0:46:37 > 0:46:39better as you get closer and closer.

0:46:39 > 0:46:42What are we going to see when we get really close?

0:46:42 > 0:46:45Having seen Saturn in your telescope with the rings,

0:46:45 > 0:46:47just looking like these little tiny ears on either side,

0:46:47 > 0:46:51we're now seeing detail and the beauty of Saturn's rings,

0:46:51 > 0:46:54looking almost like the grooves on a phonograph record.

0:46:54 > 0:46:57The rings of Saturn. What are they?

0:46:57 > 0:47:01Billions of icy particles, some the size of the house.

0:47:01 > 0:47:04They're enormous, much wider than many Earths strung together,

0:47:04 > 0:47:06but less than a kilometre thick.

0:47:07 > 0:47:11We get there and we find that it's a blizzard of features throughout the

0:47:11 > 0:47:15rings, and it got very complex.

0:47:27 > 0:47:29We'd become junkies.

0:47:29 > 0:47:33This is how you become a planetary flyby junkie,

0:47:33 > 0:47:35because you've gone through one of them,

0:47:35 > 0:47:37and you just know it's the greatest

0:47:37 > 0:47:40feeling and you want to keep doing it again and again.

0:47:40 > 0:47:42At some point,

0:47:42 > 0:47:43perhaps a year or so from now,

0:47:43 > 0:47:47it may be possible to put all this into perspective,

0:47:47 > 0:47:49but right at the moment,

0:47:49 > 0:47:55I cannot recall being in such a state of euphoria for any previous

0:47:55 > 0:47:59planetary encounter, including our two

0:47:59 > 0:48:02remarkable Voyager encounters at Jupiter.

0:48:32 > 0:48:36The largest moon of Saturn, Titan, is the most extraordinary place.

0:48:36 > 0:48:38There is a dense methane atmosphere

0:48:38 > 0:48:41where a complex organic chemistry has

0:48:41 > 0:48:43been going on for perhaps billions of years.

0:48:43 > 0:48:47And we are in a moment of extraordinary discovery.

0:48:48 > 0:48:53We had both spacecraft programmed to do identical mission at Saturn,

0:48:53 > 0:48:54and that was the prime mission.

0:48:54 > 0:48:56And it involved Titan.

0:48:57 > 0:48:58There's a huge amount of scientific

0:48:58 > 0:49:00interest in Titan because many people

0:49:00 > 0:49:03think that early in our own history our own planet may have been like

0:49:03 > 0:49:06that. So, if you want to understand the starting conditions,

0:49:06 > 0:49:08go study Titan.

0:49:08 > 0:49:11If Voyager 1 was successful at Titan,

0:49:11 > 0:49:14Voyager 2, which is nine months behind going to Saturn,

0:49:14 > 0:49:18would be free to continue to Uranus and to go on to Neptune.

0:49:18 > 0:49:22But it depended upon Voyager 1 succeeding at Titan.

0:49:22 > 0:49:24Because Voyager 1 had to be in a

0:49:24 > 0:49:26certain place in order to pass Titan,

0:49:26 > 0:49:29it couldn't go on to Uranus and Neptune.

0:49:29 > 0:49:32There was just no way to bend the trajectory to go anywhere else.

0:49:34 > 0:49:36Voyager 2 would have done exactly

0:49:36 > 0:49:39that same thing if Voyager 1 had failed.

0:49:39 > 0:49:43We would have gone like this. No more planets.

0:49:43 > 0:49:46That would have been really tough. You're going to try for Titan again

0:49:46 > 0:49:49and give up two other worlds, Uranus and Neptune.

0:49:50 > 0:49:53So, there was a lot of pressure on Voyager 1.

0:49:55 > 0:49:58Mostly what we looked at was a giant

0:49:58 > 0:50:02ball of brown smog with some sort of

0:50:02 > 0:50:04electric blue hazes above it.

0:50:04 > 0:50:08Titan did not reveal itself to the cameras of Voyager.

0:50:14 > 0:50:19But the radio signal from the spacecraft passed through the

0:50:19 > 0:50:21atmosphere of the planet and that gave them

0:50:21 > 0:50:23a measure of the pressure at the

0:50:23 > 0:50:26surface and also the temperature at the surface.

0:50:26 > 0:50:29And so we learned a lot about Titan from that radio signal.

0:50:33 > 0:50:36We had gathered what we could with Voyager spacecraft.

0:50:36 > 0:50:38Shortly after that,

0:50:38 > 0:50:40Nasa headquarters agreed that we

0:50:40 > 0:50:44should continue with Voyager 2 on its Uranus trajectory.

0:50:44 > 0:50:45So Voyager 1 had succeeded.

0:50:50 > 0:50:53We almost didn't have that mission to Uranus and Neptune if not

0:50:53 > 0:50:55for the success of Voyager 1 at Titan.

0:51:05 > 0:51:09We're getting pictures and other data back from Voyager 2,

0:51:09 > 0:51:12but at some point in time it had to go behind the planet.

0:51:12 > 0:51:16And that blocks us from getting radio signals to the Earth.

0:51:16 > 0:51:18And that happened to be in the middle of the night.

0:51:18 > 0:51:21It was a period of time, several hours that everybody knows

0:51:21 > 0:51:23we're going to be out of contact with the spacecraft.

0:51:23 > 0:51:26Everybody's expecting to pop champagne corks and say,

0:51:26 > 0:51:29"Hey, we made it!" And all the data's on the tape recorder because

0:51:29 > 0:51:31it couldn't be transmitted to the Earth.

0:51:31 > 0:51:32And instead, it popped out of the

0:51:32 > 0:51:34other side and there's all these crazy

0:51:34 > 0:51:36error signals coming from the spacecraft.

0:51:36 > 0:51:38Something bad has happened.

0:51:39 > 0:51:42Something happened right around the ring plane crossing.

0:51:42 > 0:51:45And the images that were coming back were blank.

0:51:49 > 0:51:51People thought maybe it crashed into the rings of Saturn.

0:51:51 > 0:51:53Is this it? Is it dead?

0:51:59 > 0:52:01Ladies and gentlemen, we can start the briefing.

0:52:04 > 0:52:06I wanted to make a very brief statement.

0:52:06 > 0:52:09We do have a problem on board the Voyager 2 spacecraft.

0:52:09 > 0:52:11The spacecraft has a problem.

0:52:11 > 0:52:15The scan platform operating mechanism is not operating properly.

0:52:15 > 0:52:17To make sure we understand where we're headed,

0:52:17 > 0:52:20the following instruments are mounted on the platform -

0:52:20 > 0:52:23the wide angle camera, the narrow angle camera,

0:52:23 > 0:52:24the infrared instrument,

0:52:24 > 0:52:27the ultraviolet instrument and the photopolarimeter.

0:52:27 > 0:52:32Yeah, that was the darkest, the darkest day of the whole mission.

0:52:32 > 0:52:34There is circumstantial evidence...

0:52:34 > 0:52:37I came into the auditorium and there

0:52:37 > 0:52:40was just gloom on everybody's face....

0:52:40 > 0:52:42You're beginning to speculate.

0:52:42 > 0:52:45I quickly learned what had happened.

0:52:45 > 0:52:48The scan platform had frozen.

0:52:48 > 0:52:54A frozen scan platform could be a fatal, crippling event.

0:52:58 > 0:53:00We have our speakers up...

0:53:00 > 0:53:06The rest of the Saturn mission and Uranus and Neptune were dead,

0:53:06 > 0:53:11and seeing everything that we were planning just gone.

0:53:11 > 0:53:13Just suddenly gone.

0:53:13 > 0:53:15The problem is not with the camera,

0:53:15 > 0:53:19it's with the articulated platform that moves all of the instruments.

0:53:19 > 0:53:21Our cameras, as far as we know, are working just fine.

0:53:21 > 0:53:25It's just that we're taking lots of pictures of black space.

0:53:25 > 0:53:28All of the science that we had hoped to do on Uranus and Neptune,

0:53:28 > 0:53:31there was no other spacecraft that were going to be going there.

0:53:31 > 0:53:34It was up to Voyager to do it, and all of a sudden it looked as

0:53:34 > 0:53:37though Voyager is not going to do it. It was devastating, it was.

0:53:44 > 0:53:47It took a couple of days while the engineering team went to work

0:53:47 > 0:53:49diagnosing the problem.

0:53:55 > 0:53:58It turns out the scan platform has small motors to rotate it.

0:53:58 > 0:54:01We, of course, wanted to look at lots of places,

0:54:01 > 0:54:03so we had the thing looking at lots of places.

0:54:03 > 0:54:07And the lubrication wasn't adequate, and it just jammed.

0:54:07 > 0:54:12It was frozen sort of like a car stuck in the snow.

0:54:12 > 0:54:15You tried to go forward or backward a little bit and keep working on

0:54:15 > 0:54:17it and try to get it out.

0:54:17 > 0:54:19And that's what we did with the scan platform.

0:54:19 > 0:54:23We would try to push it a little bit in one direction and it would yield

0:54:23 > 0:54:25a little bit, and then we'd push it in the other direction,

0:54:25 > 0:54:27and it would yield a little bit more,

0:54:27 > 0:54:30and then we kept doing that back and forth, back and forth.

0:54:30 > 0:54:35And, finally, that was enough to get the lubrication into the gears.

0:54:36 > 0:54:41It was freed up. And back came the spacecraft and back came the imaging

0:54:41 > 0:54:44system and there was Saturn on exit.

0:54:48 > 0:54:51Yeah.

0:54:51 > 0:54:55MUSIC PLAYS: Us and Them by Pink Floyd

0:54:57 > 0:55:01We're looking at the shadow of Saturn on the rings,

0:55:01 > 0:55:05and it was clearly from this wild, crazy angle.

0:55:06 > 0:55:09Wow. Holy cow, we're on the other side of Saturn.

0:55:11 > 0:55:17# Us

0:55:17 > 0:55:21# And them

0:55:26 > 0:55:29# And after all

0:55:29 > 0:55:33# We're only ordinary men... #

0:55:33 > 0:55:36We felt like we were there.

0:55:36 > 0:55:39Nobody even thought about it.

0:55:39 > 0:55:44Voyager was part of us. We.

0:55:44 > 0:55:49# Me

0:55:49 > 0:55:54# And you... #

0:55:58 > 0:56:01All of planetary exploration to me is a story about longing.

0:56:01 > 0:56:04It's a longing to know ourselves.

0:56:04 > 0:56:09It's a longing to understand the significance of our own existence.

0:56:09 > 0:56:12It's a longing to communicate, to say to the universe, "We're here."

0:56:12 > 0:56:16You know, "Know us." You know, "Where are you?"

0:56:16 > 0:56:21# "Forward," he cried from the rear

0:56:21 > 0:56:27# And the front rank died... #

0:56:27 > 0:56:31We have intelligent life on our own planet, dolphins and whales,

0:56:31 > 0:56:34that we cannot communicate with.

0:56:34 > 0:56:36Other than tricks for fish.

0:56:36 > 0:56:38It's a little conceited to think that, you know,

0:56:38 > 0:56:42it's going to be like Star Trek and that we'll immediately sit down for

0:56:42 > 0:56:44tea together or something.

0:56:44 > 0:56:47It's not that... It's not going to be that simple.

0:56:49 > 0:56:53The Voyager Record has a set of pictures on it that depicts our

0:56:53 > 0:56:58civilisation. But we only had the ability to do about 100 pictures.

0:56:58 > 0:57:02That was as much data as we could send, so that was kind of hard.

0:57:02 > 0:57:04It was a process of distillation.

0:57:04 > 0:57:07You can't describe the Earth in 100 pictures.

0:57:07 > 0:57:11You can't describe the Earth in 1,000 pictures.

0:57:11 > 0:57:14But what art is about is taking something

0:57:14 > 0:57:17that's small that can represent the whole.

0:57:28 > 0:57:33We thought it was very important to pick some pictures of humans nude on

0:57:33 > 0:57:36the record to show just what our anatomy was really like.

0:57:37 > 0:57:42Nasa had been seriously criticised about the Pioneer plaque.

0:57:42 > 0:57:45There were actually letters to the

0:57:45 > 0:57:50editor in newspapers saying that Nasa was sending smut to space.

0:57:50 > 0:57:52How are we going to show pictures of

0:57:52 > 0:57:55naked humans without it looking salacious?

0:57:55 > 0:57:57And the answer to that was,

0:57:57 > 0:58:00"Why don't you put a pregnant woman in the picture?"

0:58:00 > 0:58:04Because pregnant women are not considered salacious,

0:58:04 > 0:58:06not appealing sexually.

0:58:06 > 0:58:08So that's what we did.

0:58:08 > 0:58:10And I figured if this doesn't get past Nasa,

0:58:10 > 0:58:12nothing's getting past Nasa.

0:58:12 > 0:58:14And I guess the answer was nothing was getting past Nasa,

0:58:14 > 0:58:17because it was the only picture that they made us take out.

0:58:19 > 0:58:24Now it's five years of cruising out to Uranus.

0:58:24 > 0:58:27Uranus will be the most remote object yet visited by a spacecraft,

0:58:27 > 0:58:31and it's so remote that it was not even known until 200 years ago.

0:58:31 > 0:58:33It's a great distance out there, and

0:58:33 > 0:58:35if we'd launched directly from Earth,

0:58:35 > 0:58:37it would have taken 30 years to get there, so we were

0:58:37 > 0:58:40very fortunate that we could swing by Jupiter and Saturn on our way.

0:58:40 > 0:58:43I've been trying to figure this thing out for the past 25 years,

0:58:43 > 0:58:44and it's very frustrating in a

0:58:44 > 0:58:46telescope to look at that tiny little disc,

0:58:46 > 0:58:49so the next few days are going to be very exciting.

0:58:55 > 0:58:58Once we got beyond Saturn,

0:58:58 > 0:59:01essentially the engineers threw out the rule book and said,

0:59:01 > 0:59:04"How are we going to make this work?

0:59:04 > 0:59:09"How are we going to take pictures of planets this far from the sun?"

0:59:10 > 0:59:14Voyager was the first of a class of Nasa spacecraft that could be

0:59:14 > 0:59:18reprogrammed. They could take what was on the computer and just wipe it

0:59:18 > 0:59:21away and give it a whole new set of software.

0:59:21 > 0:59:25They trained the spacecraft to pirouette like a ballet dancer.

0:59:25 > 0:59:27Basically, you want to take picture of that thing,

0:59:27 > 0:59:29and it's going past you really fast,

0:59:29 > 0:59:34so you spin the whole spacecraft and follow it like this.

0:59:34 > 0:59:38And so, even though it was darker at Uranus and really dark at Neptune,

0:59:38 > 0:59:41you could leave the shutter open without smearing,

0:59:41 > 0:59:43and that was just beautiful.

0:59:44 > 0:59:46We had all of the rich set of

0:59:46 > 0:59:49goodies from Jupiter and from Saturn,

0:59:49 > 0:59:53but Uranus was unknown.

0:59:53 > 0:59:55We just had the one spacecraft, so

0:59:55 > 0:59:57we were more or less just flying blind,

0:59:57 > 1:00:00and we didn't get a second chance.

1:00:18 > 1:00:22It was like taking something that was almost fictional,

1:00:22 > 1:00:27almost mythological, and then seeing it as a real object.

1:00:27 > 1:00:30The spacecraft flew through that system like a bull's-eye,

1:00:30 > 1:00:32cos Uranus is tilted on its side,

1:00:32 > 1:00:35with this beautiful aquamarine blue methane atmosphere.

1:00:35 > 1:00:38And all these pictures, every single one of them was like, "Whoa!"

1:00:38 > 1:00:41You could hear people just... "Whoa!" And everybody would be doing

1:00:41 > 1:00:43something and somebody would go, "Whoa!"

1:00:43 > 1:00:46And everybody would turn and look up - "Oh, my gosh, look at that!"

1:00:46 > 1:00:48There was no internet, there was no

1:00:48 > 1:00:51news stream going out live to CNN.

1:00:51 > 1:00:53The only way to experience that

1:00:53 > 1:00:55sensation of being one of only a small

1:00:55 > 1:01:00group of people who saw a point of light become a world,

1:01:00 > 1:01:03the only way to experience it was to be in that room.

1:01:03 > 1:01:05Well, just about two minutes ago,

1:01:05 > 1:01:09Voyager 2 passed through its closest approach to Uranus.

1:01:09 > 1:01:11APPLAUSE

1:01:11 > 1:01:14The new ring is

1:01:14 > 1:01:17right here. Now, I don't...

1:01:18 > 1:01:20You're telling me you can't see it.

1:01:20 > 1:01:24- I can.- Dr Soderblom, as you whizzed through your explanation,

1:01:24 > 1:01:25I couldn't put it all together.

1:01:25 > 1:01:28Could you try that again?

1:01:28 > 1:01:30Slower?

1:01:30 > 1:01:33- Slower, and a few more details. - I thought that was pretty slow.

1:01:37 > 1:01:40Every time we arrived at a new planet, there were always surprises,

1:01:40 > 1:01:42even though we had gotten a lot smarter.

1:01:42 > 1:01:43For instance, before Voyager,

1:01:43 > 1:01:45all the magnetic fields have the

1:01:45 > 1:01:48magnetic pole near the rotation axis of the planet.

1:01:48 > 1:01:51And that was true for Jupiter, it was true for Saturn,

1:01:51 > 1:01:54and then we flew by Uranus, and the pole was near the equator.

1:01:55 > 1:01:59There's been a lot of speculation about the magnetosphere of Uranus.

1:01:59 > 1:02:01Would there be one? What would it be like?

1:02:01 > 1:02:06And the magnetosphere of Uranus is far more weird and wonderful...

1:02:06 > 1:02:09- VOICE-OVER:- We found the planet's tipped on its side,

1:02:09 > 1:02:13but the magnetic field is then tipped relative to the spin axis,

1:02:13 > 1:02:17so you have this huge contortion in

1:02:17 > 1:02:20the magnetic field as the planet spins around.

1:02:20 > 1:02:22Just bizarre.

1:02:22 > 1:02:26Why on Earth the magnetic field was so messed up, we had no idea.

1:02:28 > 1:02:31At the time, the Voyager 2 spacecraft flew by Uranus,

1:02:31 > 1:02:34one pole was pointing at the sun.

1:02:34 > 1:02:38At that point in its orbit, its atmosphere shuts down,

1:02:38 > 1:02:41so the planet didn't look exciting,

1:02:41 > 1:02:46and part of that is Uranus itself holding its secrets back.

1:02:46 > 1:02:50That had to be, I guess, one of the...

1:02:52 > 1:02:54Well, disappointments, in that

1:02:54 > 1:02:57Uranus was not more photogenic than it was.

1:02:57 > 1:02:59It was actually pretty blah.

1:02:59 > 1:03:01Poor Uranus.

1:03:03 > 1:03:04Poor Uranus.

1:03:18 > 1:03:23Uranus itself was not the character that Saturn and Jupiter were.

1:03:23 > 1:03:27The big stars of the Uranus encounter were actually the moons.

1:03:30 > 1:03:32The gravity assist aiming point at

1:03:32 > 1:03:37Uranus just happened to be pretty close to the orbit of Miranda.

1:03:37 > 1:03:39If Uranus had been the last stop,

1:03:39 > 1:03:41the scientists might have wanted to go to a larger moon.

1:03:41 > 1:03:44Which, ironically...

1:03:44 > 1:03:46I don't see how anything could have

1:03:46 > 1:03:48been any more interesting than Miranda.

1:03:51 > 1:03:53It looked like a jumbled up mess.

1:03:57 > 1:03:59This moon looked like it had been

1:03:59 > 1:04:03ripped to pieces and then just sort of shoved back together again.

1:04:03 > 1:04:04Whoa, come look at this.

1:04:04 > 1:04:07Going up to the screen and pointing and saying, "Did you...?

1:04:07 > 1:04:10- "Look at that, look at that." - Nobody was ready for Miranda.

1:04:10 > 1:04:13There were enormous cliffs and gashes.

1:04:13 > 1:04:16One of them, you can see the edge of a cliff.

1:04:16 > 1:04:18It's got to be ten kilometres tall.

1:04:18 > 1:04:22The gravity on Miranda is so weak that if you jumped off that cliff,

1:04:22 > 1:04:27you could read the newspaper on the way down.

1:04:27 > 1:04:30But when you hit the bottom, you'll still be going at 100mph,

1:04:30 > 1:04:32so it probably wouldn't...

1:04:33 > 1:04:35It would be the last newspaper you read.

1:04:44 > 1:04:49We were just about to present all our results,

1:04:49 > 1:04:54we were all about to have the big final finale press conference,

1:04:54 > 1:04:58and we came back from breakfast,

1:04:58 > 1:05:03and I went to go watch the shuttle being launched.

1:05:03 > 1:05:05We have main engines start.

1:05:05 > 1:05:08Four, three, two, one...

1:05:08 > 1:05:12And liftoff. Liftoff of the 25th space shuttle mission,

1:05:12 > 1:05:14and it has cleared the tower.

1:05:14 > 1:05:18And we thought, "OK, great, we'll watch the shuttle launch,

1:05:18 > 1:05:20"and then we'll go to the press conference."

1:05:20 > 1:05:22But, of course, that was Challenger.

1:05:22 > 1:05:25Engines throttling up. Three engines now at 104%.

1:05:25 > 1:05:28- Challenger, go with throttle up. - Roger, go with throttle up.

1:05:37 > 1:05:41People were just, like, astonished, just gasping like, "Oh, my...

1:05:41 > 1:05:44"Did you see that? Did it really blow up?"

1:05:44 > 1:05:47Because we had stopped in our meeting so everyone could watch it,

1:05:47 > 1:05:50and there was just silence, people were crying.

1:05:52 > 1:05:54Well, what can you say?

1:05:54 > 1:05:57You knew right away that a bunch of people were dead.

1:05:59 > 1:06:02- RADIO:- ..reports vehicle exploded.

1:06:05 > 1:06:07Copy.

1:06:07 > 1:06:09And then, of course, they showed

1:06:09 > 1:06:13replays and replays and replays over and over and over again.

1:06:13 > 1:06:15We have no downlink.

1:06:15 > 1:06:18OK, everybody, stay off the telephones,

1:06:18 > 1:06:22make sure you maintain all your data, start pulling it together.

1:06:22 > 1:06:25The Challenger accident happened as we were receding from Uranus.

1:06:25 > 1:06:29I have this vivid memory of picture after picture of the crescent Uranus

1:06:29 > 1:06:33coming back and the replay of the Challenger explosion

1:06:33 > 1:06:35and it was just devastating.

1:06:35 > 1:06:39- RONALD REAGAN:- Today is a day for mourning and remembering.

1:06:39 > 1:06:42Nancy and I are pained to the core about the tragedy of the shuttle

1:06:42 > 1:06:44Challenger. We know we share this

1:06:44 > 1:06:47pain with all the people of our country.

1:06:47 > 1:06:49This is truly a national loss.

1:06:49 > 1:06:53I know it's hard to understand, but sometimes painful things like this

1:06:53 > 1:06:57happen. It's all part of the process of exploration and discovery.

1:06:57 > 1:07:02It's all part of taking a chance and expanding man's horizons.

1:07:02 > 1:07:05The future doesn't belong to the faint-hearted.

1:07:05 > 1:07:07It belongs to the brave.

1:07:08 > 1:07:11Report from the flight indicate

1:07:11 > 1:07:13the impact in the water approximately

1:07:13 > 1:07:1828.64 degrees north, 80.28 degrees west.

1:07:22 > 1:07:25During these close approach time periods,

1:07:25 > 1:07:30we would have hundreds of reporters come to JPL and it was a great

1:07:30 > 1:07:33news atmosphere and when the

1:07:33 > 1:07:36Challenger exploded... everybody just left.

1:07:38 > 1:07:40It was really a very sad time.

1:07:40 > 1:07:43A sad ending to another great mission.

1:07:52 > 1:07:55Those cosmic questions we hope to learn by sending our machines out

1:07:55 > 1:07:57are the very same questions that you

1:07:57 > 1:08:00and I and every child has asked themselves. "Where do we come from?"

1:08:00 > 1:08:02"Are we alone?" "What's the universe made of?"

1:08:02 > 1:08:03"How will it end?" All of these

1:08:03 > 1:08:06basic questions are the questions that drive science.

1:08:10 > 1:08:11I do cosmology.

1:08:11 > 1:08:14I study the beginning and end of the universe and some people say,

1:08:14 > 1:08:16"What's that good for?" And I always say to them, "You know,

1:08:16 > 1:08:18"you don't ask what's a Mozart symphony good for,

1:08:18 > 1:08:20"or a Picasso painting."

1:08:20 > 1:08:23But science somehow seems, in order to be useful for people,

1:08:23 > 1:08:24it has to produce technology.

1:08:24 > 1:08:27But the beautiful thing about science is the ideas.

1:08:42 > 1:08:45There it was, just sitting out on the edge of our solar system,

1:08:45 > 1:08:49waiting for somebody to come out and appreciate its beauty,

1:08:49 > 1:08:55just waiting for the day that humans would get out there and go, "Wow!"

1:08:55 > 1:08:58Neptune was photogenic right from the beginning.

1:08:58 > 1:08:59I had been taking pictures of

1:08:59 > 1:09:04Neptune from the ground where we couldn't see very much. You know,

1:09:04 > 1:09:07in my head imagining what it might look like and seeing that turned

1:09:07 > 1:09:10into reality, it's a rush.

1:09:10 > 1:09:18Looking at this blue, bright blue orb, it was evocative of the Earth,

1:09:18 > 1:09:22which was bizarre for the last planet that we were flying by.

1:09:22 > 1:09:26I was a meticulous log taker and I would make little notations in these

1:09:26 > 1:09:30logs and I would draw little pictures and you can see,

1:09:30 > 1:09:32"What's this little dark spot?"

1:09:32 > 1:09:34"Bright clouds." I'm like, "Wow!"

1:09:34 > 1:09:36Wow, exclamation point!

1:09:36 > 1:09:38And I'd draw pictures and arrows.

1:09:38 > 1:09:42The most surprising thing was a giant dark spot.

1:09:43 > 1:09:46Nobody had any idea that would be there.

1:09:46 > 1:09:49It's huge, it's like a hole in the planet.

1:09:49 > 1:09:51So we called it the great dark spot

1:09:51 > 1:09:54because we're not very original when it comes to names.

1:10:00 > 1:10:05We had to basically make a forecast of the storms on Neptune in order to

1:10:05 > 1:10:10point the cameras during the last day, and at the same time,

1:10:10 > 1:10:12there was a hurricane off the

1:10:12 > 1:10:16East Coast of the US and the weather forecasters were

1:10:16 > 1:10:19trying to forecast that hurricane.

1:10:19 > 1:10:22But they were trying to forecast it 12 hours in advance,

1:10:22 > 1:10:24and they were having a lot of

1:10:24 > 1:10:28trouble because the storm kept changing position, and we were just

1:10:28 > 1:10:31calmly plotting points on graph paper and then say

1:10:31 > 1:10:34"OK, two weeks from now this storm's going to be right here."

1:10:34 > 1:10:36And it usually was.

1:10:41 > 1:10:43At Jupiter, Saturn and Uranus,

1:10:43 > 1:10:46the goal was to do a flyby that

1:10:46 > 1:10:50would take the spacecraft on to the next planet.

1:10:50 > 1:10:52When it came to Neptune,

1:10:52 > 1:10:54we knew that that was the last

1:10:54 > 1:10:56planet we were going to fly by and so we

1:10:56 > 1:10:59could take a different trajectory.

1:10:59 > 1:11:01This allowed us to get a really

1:11:01 > 1:11:03spectacular view of the rings and then

1:11:03 > 1:11:07look back on the system in a way that was quite beautiful.

1:11:09 > 1:11:12Think about imaging the rings of Neptune.

1:11:12 > 1:11:13They have reflectivity which is

1:11:13 > 1:11:16twice as dark as soot and the light that's

1:11:16 > 1:11:18falling on them is 1,000 times

1:11:18 > 1:11:21fainter than on Earth, so you have one 1000th

1:11:21 > 1:11:23of the light and you're trying to

1:11:23 > 1:11:25image something which is twice as dark

1:11:25 > 1:11:27as soot against a jet black background.

1:11:27 > 1:11:30More than one ring could be seen, even in the raw images,

1:11:30 > 1:11:32the so-called ring arcs,

1:11:32 > 1:11:36and it seemed reasonable that this was indeed the lost arc that our

1:11:36 > 1:11:39imaging team raiders were looking for.

1:11:39 > 1:11:42GROANING

1:11:42 > 1:11:44LAUGHTER

1:11:44 > 1:11:47Now you're going to turn on me, are you?!

1:11:47 > 1:11:51We knew at Neptune we wanted a close flyby of Triton,

1:11:51 > 1:11:55which was a huge world and a retrograde orbit around Neptune.

1:11:55 > 1:11:59If you looked at them on the way in, they weren't lined up.

1:11:59 > 1:12:02One's up here and one's down here, so what are you going to do?

1:12:02 > 1:12:04Well, there was a way to fly over

1:12:04 > 1:12:07the north pole very close to Neptune to

1:12:07 > 1:12:10bend the spacecraft so it would go down.

1:12:10 > 1:12:11That meant getting to within just a

1:12:11 > 1:12:13few thousand miles of the cloud tops,

1:12:13 > 1:12:18skimming the surface, and it had to hit that, you know, exactly right.

1:12:19 > 1:12:23There was a lot of concern that we didn't know enough about Neptune's

1:12:23 > 1:12:29atmosphere to really be sure that the spacecraft would not tumble.

1:12:29 > 1:12:30Just a slight error in the

1:12:30 > 1:12:33calculations and instead of skimming across the

1:12:33 > 1:12:37cloud tops, you're skimming into the clouds and the spacecraft burns up.

1:12:37 > 1:12:40Slight error the other way, you go a little too far,

1:12:40 > 1:12:41you don't bend enough,

1:12:41 > 1:12:44maybe you run right into Triton and crash and that's the end of the

1:12:44 > 1:12:46mission. You don't have enough time,

1:12:46 > 1:12:49you have to make your last, best guess, hit the send button...

1:12:51 > 1:12:53It would have been just fascinating to be hanging

1:12:53 > 1:12:55on to that spacecraft, right?

1:12:55 > 1:12:57Skimming over these beautiful blue

1:12:57 > 1:13:00cloud tops of Neptune, and then as you come

1:13:00 > 1:13:03over the pole of Neptune, seeing that big moon Triton rise up.

1:13:11 > 1:13:14After several billion miles of journey, to get us to within a few

1:13:14 > 1:13:18kilometres of where we need to be, it's just absolutely remarkable.

1:13:18 > 1:13:21You know, threading an incredible needle.

1:13:22 > 1:13:25The Southern hemisphere of Triton

1:13:25 > 1:13:27is entirely covered with nitrogen ice

1:13:27 > 1:13:31and as we flew past, then we go again,

1:13:31 > 1:13:35as we flew past, we were able to look down at

1:13:35 > 1:13:39markings on the surface of the polar cap.

1:13:39 > 1:13:43We were putting together a mosaic of Triton's globe,

1:13:43 > 1:13:47but we couldn't get things to line up quite right.

1:13:47 > 1:13:51Some of the dark streaks, two in particular, would not line up.

1:13:51 > 1:13:53He's, like, just scratching his head, like,

1:13:53 > 1:13:55"I have no idea what's going on here."

1:13:55 > 1:13:59This guy's one of the world's experts on anything having to do

1:13:59 > 1:14:02with planets and moons and he can't figure this out.

1:14:02 > 1:14:05The only crazy idea that's left is eruptions.

1:14:07 > 1:14:09I said, "Well, let's put it in a stereo viewer" -

1:14:09 > 1:14:10red and blue glasses.

1:14:14 > 1:14:15And the images fused into a

1:14:15 > 1:14:19three-dimensional model and up popped these guys.

1:14:23 > 1:14:25And I said, "Holy moly!"

1:14:25 > 1:14:27And so we knew what we had.

1:14:39 > 1:14:46These plumes. Black geysers spewing out this stuff.

1:14:46 > 1:14:53The plumes extending out of the surface for, like, kilometres.

1:14:53 > 1:14:55We were seeing eruptions on a world

1:14:55 > 1:14:59which should have been just a frozen cinder.

1:14:59 > 1:15:01This is too much.

1:15:01 > 1:15:04The last place we would have expected to see further dynamics,

1:15:04 > 1:15:08further eruptions, was in a moon this remote in the solar system.

1:15:08 > 1:15:11So there's solar-driven geysers on a

1:15:11 > 1:15:16satellite that's 30 astronomical units from the sun.

1:15:16 > 1:15:18Who would have thought?

1:15:18 > 1:15:21Just because an idea's crazy it's not necessarily wrong.

1:15:21 > 1:15:25This was the last planet Voyager would explore before it headed on

1:15:25 > 1:15:30for the rest of its journey and so I think the times together as a team,

1:15:30 > 1:15:33the times to look at the pictures, talk,

1:15:33 > 1:15:36meet together, became more precious.

1:15:36 > 1:15:40I was passing by the secretary's desk and she said,

1:15:40 > 1:15:43"Oh, Candy, there's a reporter that wants to talk to you."

1:15:44 > 1:15:46And he said,

1:15:46 > 1:15:49"The countdown clock just went from

1:15:49 > 1:15:51"minus, counting down,

1:15:51 > 1:15:55"to counting up.

1:15:55 > 1:15:58"Voyager's now leaving Neptune."

1:15:58 > 1:16:01And he said, "How does that make you feel?"

1:16:02 > 1:16:05And in that moment, I dissolved into tears.

1:16:07 > 1:16:08After the spacecraft went past,

1:16:08 > 1:16:12I turned around and looked back and there's this beautiful crescent,

1:16:12 > 1:16:14Neptune and Triton, and people

1:16:14 > 1:16:16realised that's the end of the planetary

1:16:16 > 1:16:19part of Voyager, that's the last port of call,

1:16:19 > 1:16:23the last thing that we'll see in our solar system is now behind us.

1:16:23 > 1:16:26And it went from the Voyager planetary mission

1:16:26 > 1:16:28to the Voyager interstellar mission.

1:16:28 > 1:16:31We could have enhanced the colour a

1:16:31 > 1:16:33bit to make a somewhat prettier picture,

1:16:33 > 1:16:36but out of respect to the Voyager spacecraft,

1:16:36 > 1:16:39we decided to show it to you just as it is.

1:16:42 > 1:16:43Wow!

1:16:43 > 1:16:46APPLAUSE

1:16:46 > 1:16:52So this was Voyager's farewell to us and it's our farewell to you.

1:16:53 > 1:16:57The way I looked at it was, "See, we did something really great."

1:16:59 > 1:17:01Very, very successful mission.

1:17:01 > 1:17:04A little weepy. I mean,

1:17:04 > 1:17:08there was a lot of energy put into this mission.

1:17:09 > 1:17:12We have ignition and we have liftoff.

1:17:20 > 1:17:24Years of intense effort.

1:17:25 > 1:17:28It was the end of a sentimental journey.

1:17:32 > 1:17:35We did it. We pulled it off.

1:17:35 > 1:17:38And that's important. It is.

1:17:38 > 1:17:41MUSIC PLAYS: Johnny B. Goode by Chuck Berry

1:17:41 > 1:17:44# And he could play a guitar just like a-ringing a bell

1:17:44 > 1:17:47# Go go Go Johnny Go... #

1:17:47 > 1:17:49We had a big party at JPL.

1:17:49 > 1:17:52Chuck Berry was there, so that was a good send off for Voyager.

1:17:52 > 1:17:56# Go go Go Johnny Go

1:17:56 > 1:18:01# Go Johnny B Goode... #

1:18:01 > 1:18:04Rock star moment and sail on, Voyager.

1:18:06 > 1:18:07And I'm going to go and get some

1:18:07 > 1:18:11sleep or maybe I'll do a little more dancing. Thank you very much.

1:18:11 > 1:18:13CHEERING

1:18:14 > 1:18:16Meanwhile, Voyager 1 is still kind

1:18:16 > 1:18:18of cruising out there, getting farther

1:18:18 > 1:18:21and farther out, and a number of folks on the team,

1:18:21 > 1:18:22including Carl Sagan,

1:18:22 > 1:18:26had this idea that before we had to shut the cameras down let's turn

1:18:26 > 1:18:30around, look back towards the sun, and let's take a picture of our

1:18:30 > 1:18:33solar system unlike any that had ever been taken before.

1:18:33 > 1:18:35And there was actually opposition to it.

1:18:35 > 1:18:37They just didn't want to do it.

1:18:37 > 1:18:40They couldn't get their heads around what would be the point of taking a

1:18:40 > 1:18:43picture of the Earth and Jupiter and so on because they're just going to

1:18:43 > 1:18:45be little points of light.

1:18:45 > 1:18:48So Carl being Carl actually went all

1:18:48 > 1:18:50the way to the Nasa administrator and

1:18:50 > 1:18:53got the Nasa administrator to direct

1:18:53 > 1:18:57the Jet Propulsion Laboratory to take this series of pictures.

1:18:57 > 1:19:00Absolutely zero science in it, absolutely none.

1:19:09 > 1:19:12People have been taking selfies of our planet for as long as the space

1:19:12 > 1:19:13programme's been going on.

1:19:13 > 1:19:15No-one had ever taken one like this.

1:19:15 > 1:19:18And they ended up on Valentine's Day, 1990,

1:19:18 > 1:19:21taking this beautiful family portrait.

1:19:25 > 1:19:27When we did our portrait of each of the planets,

1:19:27 > 1:19:30I was the first person to look at he pictures,

1:19:30 > 1:19:33and I knew every blemish and so I could pretty

1:19:33 > 1:19:36quickly go, "Blemish, blemish, blemish," and I thought,

1:19:36 > 1:19:40"Well, where's the Earth? How could we...?" You know.

1:19:40 > 1:19:43And then I realised there was a lot of...

1:19:43 > 1:19:47There were a lot of streaks of light in that image

1:19:47 > 1:19:50and I realised finally that the

1:19:50 > 1:19:54Earth was sitting in one of those rays of light.

1:19:55 > 1:19:59You know, I just sat there for a while just kind of realising,

1:19:59 > 1:20:01"Wow, that's the Earth," you know.

1:20:01 > 1:20:04"That's Voyager looking back at the Earth."

1:20:04 > 1:20:07And so this is a different kind of milestone than the scientific

1:20:07 > 1:20:08milestones we've had.

1:20:08 > 1:20:10One, it is really symbolic...

1:20:10 > 1:20:12I'm an imaging scientist so I first realised

1:20:12 > 1:20:16"Oh, this didn't turn out the way we thought it was going to turn out,"

1:20:16 > 1:20:17and my first impulse is to take my

1:20:17 > 1:20:21hand and wipe away the dust because there was some dust on it.

1:20:21 > 1:20:23Well, one of the pieces of dust that I wanted to wipe

1:20:23 > 1:20:26away was the Earth!

1:20:26 > 1:20:30But it didn't matter because in the hands of Carl he turned it into an

1:20:30 > 1:20:33allegory on the human condition.

1:20:33 > 1:20:35And the next slide...

1:20:42 > 1:20:44The Earth in a sunbeam.

1:20:47 > 1:20:49In this colour picture, you can see

1:20:49 > 1:20:51that it is in fact less than a pixel,

1:20:51 > 1:20:55and this is where we live, on a blue dot.

1:20:55 > 1:20:58On that blue dot,

1:20:58 > 1:21:03that's where everyone you know and everyone you ever heard of and every

1:21:03 > 1:21:05human being who ever lived...

1:21:05 > 1:21:07lived out their lives.

1:21:08 > 1:21:12I think this perspective underscores

1:21:12 > 1:21:15our responsibility to preserve and

1:21:15 > 1:21:19cherish that blue dot, the only home we have.

1:21:21 > 1:21:23My father talks about this little,

1:21:23 > 1:21:26tiny speck in this vast cosmic night,

1:21:26 > 1:21:28and that we're part of something bigger

1:21:28 > 1:21:30and we're also, you know, alone.

1:21:30 > 1:21:33There's a great thing where he says, "There's no sign that any

1:21:33 > 1:21:37"help is going to come here to save us from ourselves. It's up to us."

1:21:37 > 1:21:41HEARTBEAT

1:21:59 > 1:22:01After Neptune, the project continued,

1:22:01 > 1:22:04but it continued in quite a different way.

1:22:04 > 1:22:07The Voyagers didn't have any more encounters,

1:22:07 > 1:22:11they were just sailing on out into interstellar space,

1:22:11 > 1:22:13which people didn't really

1:22:13 > 1:22:15understand how far that was going to be.

1:22:18 > 1:22:22At the time we were designing Voyager, interstellar space,

1:22:22 > 1:22:25where the boundary was, was totally unknown.

1:22:27 > 1:22:31We had our eyes on an interstellar mission.

1:22:31 > 1:22:35Are we going to push the spacecraft to get out of our solar system and

1:22:35 > 1:22:37into the galaxy?

1:22:37 > 1:22:40It was a shot in the dark because nobody knew how far.

1:22:43 > 1:22:46Uncharted waters.

1:22:46 > 1:22:50- Goldstone. Voyager. - Voyager to Goldstone.

1:22:50 > 1:22:54Please turn command modulation on at 1800.

1:22:54 > 1:22:59Goldstone, copy, 1800 for command.

1:23:21 > 1:23:22We know the sun has this

1:23:22 > 1:23:24gravitational influence that goes way out,

1:23:24 > 1:23:26almost halfway to the nearest star,

1:23:26 > 1:23:28so in terms of gravity at the edge of the solar system,

1:23:28 > 1:23:31it's going to take Voyager tens of thousands of years to get there.

1:23:31 > 1:23:35But the magnetic field of the sun can only extend so far.

1:23:35 > 1:23:36It's a bubble around our star.

1:23:36 > 1:23:39We can see the bubbles round other stars out there.

1:23:39 > 1:23:40Where's our bubble end?

1:23:40 > 1:23:44Where does the influence of the sun give way to the galaxy?

1:23:46 > 1:23:49We kept going, and years went by and years went by,

1:23:49 > 1:23:52and we don't detect the interstellar medium.

1:23:57 > 1:24:01Throughout the 1990s, still didn't find the edge of the bubble.

1:24:01 > 1:24:06Throughout the 2000s, still didn't find the edge of the bubble.

1:24:06 > 1:24:09And then finally Voyager 1, which is going the fastest,

1:24:09 > 1:24:11which is the farthest,

1:24:11 > 1:24:14started to see these funny things happen to the squiggly lines.

1:24:14 > 1:24:17A crazy spike and everybody goes, "Oh, is that it?"

1:24:17 > 1:24:19And then it goes back to normal.

1:24:19 > 1:24:25And then there was just literally one magical day in August 2012 that

1:24:25 > 1:24:28everything changed and it was like

1:24:28 > 1:24:30it just popped out of the bubble.

1:24:30 > 1:24:32Voyager 1 has left our solar system.

1:24:32 > 1:24:33It's the first thing built by

1:24:33 > 1:24:35humans that has left our solar system.

1:24:35 > 1:24:37Now it's in interstellar space.

1:24:37 > 1:24:41Major historic announcement by Nasa just a short time ago confirming the

1:24:41 > 1:24:43Voyager spacecraft,

1:24:43 > 1:24:45Voyager as in the thing that

1:24:45 > 1:24:49launched way back in 1977, exploring the moons, exploring the planets,

1:24:49 > 1:24:52well, it has entered interstellar space.

1:24:52 > 1:24:54We've slipped the outermost grasp

1:24:54 > 1:24:56of our solar system with Voyager 1,

1:24:56 > 1:25:01the first human-made object to venture into interstellar space.

1:25:01 > 1:25:03It's a wonderful achievement, actually, when you think about it,

1:25:03 > 1:25:07it's as historic as our first step out of our bubble, which, you know,

1:25:07 > 1:25:09has been around all the planets and

1:25:09 > 1:25:11around the Earth essentially forever,

1:25:11 > 1:25:13and now finally some little thing

1:25:13 > 1:25:15that we have built has left that bubble

1:25:15 > 1:25:18and is in the space between the stars.

1:25:18 > 1:25:22We all feel like Voyager has carried a bit of us into the galaxy.

1:25:41 > 1:25:44There's never going to be another mission like it.

1:25:44 > 1:25:47It was the first and last of its own kind.

1:25:47 > 1:25:50Is the universe any different than it was then?

1:25:50 > 1:25:53No. But are we different?

1:25:53 > 1:25:55Absolutely.

1:25:56 > 1:25:59The thrill of the discoveries,

1:25:59 > 1:26:02completing the Grand Tour, I mean, man,

1:26:02 > 1:26:06our child just made it.

1:26:06 > 1:26:11Voyager 1 and Voyager 2 will be orbiting the centre of the Milky Way

1:26:11 > 1:26:14galaxy with all the stars and every 200 and, roughly,

1:26:14 > 1:26:1750 million years it will complete an

1:26:17 > 1:26:20orbit around the centre of the galaxy.

1:26:20 > 1:26:23There's no wind, water, rain, weathering.

1:26:23 > 1:26:25There's no planets it's going to run into,

1:26:25 > 1:26:29there's no asteroid belts or comets that they're going to run into.

1:26:29 > 1:26:34And over billions of years, they're predicted to remain pretty intact.

1:26:34 > 1:26:36We're the generation that sent

1:26:36 > 1:26:39something out into space that's not only

1:26:39 > 1:26:43going to outlive us, it's going to outlive our star.

1:26:43 > 1:26:47Four billion years from now, when our sun turns into a red giant,

1:26:47 > 1:26:52Voyager's still going to be trucking out there through the stars,

1:26:52 > 1:26:55and the songs of our time are going to be out there.

1:26:55 > 1:26:58Chuck Berry is still out there.

1:26:58 > 1:27:00We'll still be out there.

1:27:00 > 1:27:04When the Voyager's power sources go dead and when

1:27:04 > 1:27:09the spacecraft can no longer send back any useful information,

1:27:09 > 1:27:14that's really the point at which the Golden Record becomes the primary

1:27:14 > 1:27:17function of those missions,

1:27:17 > 1:27:19still floating somewhere in

1:27:19 > 1:27:23interstellar space, completing the last part of the mission.

1:27:35 > 1:27:37All of the human tragedies and the

1:27:37 > 1:27:40greatest triumphs in our existence as a

1:27:40 > 1:27:41species, all of that's going to be

1:27:41 > 1:27:44forgotten and the universe doesn't care about it.

1:27:44 > 1:27:47But it is possible that at least one thing we've created will be

1:27:47 > 1:27:50out there, and who knows, maybe someday, with an

1:27:50 > 1:27:53infinitesimally small chance, another being might

1:27:53 > 1:27:56find it and at least know of our existence.

1:27:56 > 1:27:58It's highly unlikely, but it's not

1:27:58 > 1:28:01impossible and that small possibility

1:28:01 > 1:28:03surely gives us hope.

1:28:05 > 1:28:11We will continue to get signals back from Voyager and we will continue to

1:28:11 > 1:28:14try and get signals back from Voyager as long as we can.

1:28:14 > 1:28:16There will be a day

1:28:16 > 1:28:20when the antennas are listening to Voyager

1:28:20 > 1:28:22and we don't hear anything.

1:28:25 > 1:28:28And that will be the day that

1:28:28 > 1:28:31we stop communications with Voyager.

1:28:33 > 1:28:35And that will be very sad.

1:28:35 > 1:28:38Because it will have gone silent and

1:28:38 > 1:28:42we really won't have a chance to say goodbye.

1:28:42 > 1:28:45# We've won the race

1:28:45 > 1:28:51# We've claimed our place forever

1:28:51 > 1:28:55# Cold and lost in space

1:28:55 > 1:28:59# We've won the race

1:28:59 > 1:29:04# We've claimed our place forever

1:29:04 > 1:29:08# Cold and lost in space

1:29:08 > 1:29:12# I've found this inner dance

1:29:12 > 1:29:15# Our thoughts will start to fray

1:29:15 > 1:29:21# Forever cold and lost in space

1:29:22 > 1:29:25# I feel I'm going down

1:29:25 > 1:29:28# There's no more solid ground

1:29:28 > 1:29:33# Forever cold and lost in space... #