Original subtitles

Three, two, one, zero.

In August 1977, two spacecraft called

Voyager began an incredible journey.

If they could survive the dangers that lay across billions

of miles of space, they would reach worlds more distant

and strange than anyone could possibly have imagined.

The gas giants.

Voyager was heading towards four vast planets,

each thousands of times bigger than the Earth.

Jupiter with it's strange bands of cloud,

and it's great red spot.

A world crackling with radiation

that can be heard from Earth.

Beyond Jupiter was Saturn.

How did this planet alone come to have it's

spectacular set of rings?

Stranger still was Uranus.

It was known from how it's moons orbited, that Uranus had

been tipped over on it's back.

But how had this happened?

Neptune was barely visible, even through the most

powerful telescopes.

What kinds of world's were these?

And what could they reveal about the solar system of which

Earth is such a tiny part.

Roger zero G and I feel fine.

Capsule is turning around.

Oh, that view is tremendous.

In the early 1960's, sending a spacecraft

all the way to the giants was unthinkable.

Men had flown just a few hundred miles up in orbit

around the Earth.

Unmanned probes ventured further, but only to the nearest

planets, Venus and Mars.

Signal level has gone way down.

Report continuing low signal levels.

Even this was pushing the very limits

of what was possible.

In 1964, the first spacecraft,

Mariner 4, flew by Mars.

The spacecraft just barely made it there.

Yes, it's there.

And so the concept to go on to Jupiter

which was almost half a billion miles away,

Saturn, almost a billion, Uranus, almost two and

Neptune, almost 3 billion miles away and all up

12 years in journey,

was not even something one could very easily imagine.

A solution came from a most unlikely source.

A young student at NASA's Jet Propulsion Laboratory was

asked to calculate trajectories for a flight to Jupiter.

I was a summer student working on my degree at the time.

So when I was given the job of looking at the outer planets,

I thought that was like a make-work project.

I was kind of being kept out of the way while the really

important business of getting to Mars was underway.

Flandro discovered something that made the

dream of a flight to the giant planets a real possibility.

Obviously, the first thing is to determine when the

planets are going to be in positions

where we could reach them.

So I drew very careful maps of where the planets would be

and one of the most important drawings was one in which I

drew the positions of the planets versus the date.

And the thing that caught my attention immediately was

that the lines for Jupiter, Saturn, Uranus and Neptune all

crossed in about the 1975, 76 time period.

In other words, those four major planets were on the

same side of the sun and in the

same general position at the same time.

So it gave me the idea immediately that we could do all of

those planets with one flight.

Flandro's discovery meant it might now be

possible to travel further into our Solar System.

Rocket power alone could propel a spacecraft

no further than Jupiter.

But scientists knew that if a probe approached

a planet at the right angle,

it would be caught by the planet's momentum.

Then pitched off in a new direction at a greater speed.

The trick you use here is you fire your rocket with

enough propulsion to get to Jupiter.

Which is after all, a long ways away.

It's five times the distance of the Sun.

Go by Jupiter in just the right way that you get a

gravitational slingshot effect.

That propels you to Saturn.

Same trick, if Saturn is in the

right place at the right time.

Which can propel you to Uranus if Uranus is in the

right place at the right time and on to Neptune.

Same deal.

That happens about every 175 years.

And it happened in terms of launch date in 1977.

And in fact, former administrator of NASA, Tom Paine,

used to make the joke that the last time this happened,

Thomas Jefferson was President, and he blew it.

For NASA, this was too good an opportunity to miss.

They announced a mission to the giants called Voyager.

It marked a new era for astronomers who had struggled to

understand the hazy views they could see from telescopes

based on Earth.

The man chosen to lead the imaging team was Brad Smith.

I had started looking at Jupiter seriously

back in the late 50's.

But we were frustrated by the difficulty of making such

observations from the ground.

And so when the opportunity came up to be involved with

Voyager, as I realised for the first time I was

gonna have that opportunity to see Jupiter up close.

To see detail we could never could possibly

see from the ground.

The hopes of astronomers now lay in the hands

of the mission engineers who faced what seemed an

impossible task.

The comment that I frequently heard from those I was

working with was "That mission is never going to happen."

It's just too complicated.

We had to build a machine that could fly for perhaps

10 years without failing, and that was really

pushing the limits of what we thought we could do

with electronics at that time.

We had to pass through the asteroid belt on the way.

How can we get this large spacecraft through that very

dangerous area beyond Mars without a collision?

And that seemed to be a very, very, very challenging task.

One of the big worries was data transfer.

Even if you could do this flight, could we get any useful

data back to the Earth?

So there a great deal of worry about that.

The engineers had a decade to make the

Voyager mission possible.

Around the world, giant antennae were built.

The deep space network ready to communicate with probes

across billions of miles.

But it still wasn't known if a spacecraft could survive

hazards like the asteroid belt, the band of drifting rocks

between Mars and Jupiter.

Voyager would have only one chance, so two less elaborate

probes were sent ahead to test the route.

Pioneer 10 and 11 were launched to Jupiter and Saturn.

Pioneer 10 and 11 were a very important part of the

strategy in exploring the outer solar system.

It was critical to have the Pioneers lead the way telling

us about the environment and making some very important

discoveries which would then allow us with the Voyagers to

come in safely behind.

James van Allen was a veteran of missions to

Mars and Venus.

Now he led a team of scientists on Pioneer.

Piopneer 10 was the first venture beyond Mars.

First time we were going at such enormous distances.

First time we were about to cross the asteroid belt which

lies between the orbits of Mars and Jupiter.

So it was a very hazardous and high risk mission.

And we had a keen sense of it's historic possibilities and

emblazing a trail to the outer planets.

Pioneer 10 successfully got through the asteroid belt and

it was still performing beautifully.

And so we now knew that in fact it was possible to get to

the outer planets safely.

Another key question which Pioneer 10 had to address was

"How intense was the radiation environment around Jupiter?"

Since the 50's, radio emissions had been

detected coming from Jupiter suggesting there might be

intense radiation around the planet.

The man whose task it was to investigate this was

James van Allen.

He had discovered bands of radiation around Earth with

the very first American satellite.

These were later named the "Van Allen belts."

We have encountered a very high intensity of radiation,

which is of the order of 1,000 times as intense as could be

attributed to cosmic rays as ordinarily understood.

Van Allen predicted large radiation belts

around Jupiter.

But even he did not anticipate what Pioneer found.

As we went in, the radiation intensity got greater and

greater and greater and greater and greater and greater.

And there was a very strong apprehension about the

survival of the electronic equipment in this spacecraft.

But it went up to a maximum, kept going up and up,

and we did survive, and then it started going down again,

so we could breathe a sigh of relief

that we had finally made it.

The radiation belts surrounding Jupiter

turned out to be 10,000 times more intense than Earth's.

And Pioneer also encountered a vast magnetic field

stretching seven million miles out from the planet.

One thing that Pioneer 10 discovered was that Jupiter's

magnetic field is the largest structure in the solar system.

If you could see it from the Earth, in the sky, it would

appear to be as large as the sun.

Even though it's five times further away.

But of course, it's invisible and this is very damaging

to spacecraft and can damage electronics.

The Voyager probes had to be hurriedly

redesigned to survive the intense magnetic field

and radiation belts of Jupiter.

Pioneer saved our lives.

Had we flown into that unknowingly, with a more

sophisticated electronics and the more sophisticated

mechanisms that we had on Voyager,

we would have died right on the spot.

We were well into the design of that spacecraft when the

Pioneer results came in.

And we had to do a lot of redesign.

As the launch date grew near,

final preparations were made for Voyager.

For any curious extra-terrestrials they might meet,

the probes carried a disc showing where they had come from,

and a collection of images from Earth.

This was a moment that I had imagined and thought about

for years and there it was happening.

Here was our spacecraft on the way to Jupiter and Saturn

and Uranus and Neptune.

A very marvelous feeling indeed.

This was the world were Voyager was heading.

It was nearly four centuries since Galileo had turned the

first telescope on Jupiter and discovered

four points of light moving around the planet.

These were it's four moons.

The first proof that not everything in the Universe revolves

around the Earth.

For Voyager's chief scientist, the mission promised a new

era of discovery.

I think we all felt that we were in the tradition of Galileo

who was the first to see the moon's of Jupiter.

And the first to apply an instrument

to increase our ability to observe the universe.

Voyager is just the latest tool which we as a civilization

had managed to devise and of course, the tool was so

powerful that we saw things nobody had seen before,

and that nobody had imagined we'd see.

The probe was still 50 million miles from

Jupiter when it sent back the views

everyone had been waiting for.

We all approached Jupiter with great expectation and

we all had grandiose theories about what we were gonna see.

But of course, Jupiter fooled us all.

There was some bizarre behavior, little clouds moving

along and being swept up in the great red spot and them

being, it would spit them out again.

Other clouds roll along next to one another, coalesce into

a single cloud and then break apart again.

Those kinds of details are not understood.

Not even now, not 20 years later.

That first encounter with Jupiter

was a marvelous time for me,

especially the approach shots showing the planet

revolving and watching the great red spot revolving.

Getting closer and closer until finally we could see that

indeed this was the top of a large storm.

As a child, I'd studied that, and wondered if that was a

storm or was that an island floating in an ocean.

It was very difficult to know and finally, the answers were

there before our eyes.

Voyager revealed an atmosphere of hydrogen and

helium gas with huge clouds moving much faster

than had been imagined.

Jupiter's winds gusted at hundreds of miles an hour, and

the red spot alone was three times the size of the Earth.

It was the greatest storm in the solar system.

Voyager hinted at why this should be.

It found that Jupiter pushes out twice as much energy

as it receives from the Sun.

Suggesting that it's core must be hot.

Scientists now believe that at the heart of this massive

planet, the gases are compressed

until they become a metallic liquid.

This hot churning core could be the powerhouse that drives

Jupiter's winds.

And like a dynamo, creates the enormous magnetic fields

around the planet.

Voyager then turned it's cameras towards Jupiter's moons.

At the time of the encounter,

Bruce Murray was head of J.P.L.

Just before the mission, the interest was on the planet,

on those bands, the things that you could

see through a telescope.

There was hardly any interest at all in the satellites of

the planets because they were mostly little spots,

some of them we couldn't even see, or course.

I had to lead a one man crusade to even have them listed as

targets for Voyager when it went there.

Scientists had expected the moons of Jupiter

to be cold, dead and covered in craters,

like our own moon.

What they found was a mixture of worlds as different and

surprising as the planets themselves.

Io, the closest of Jupiter's large moons turned out to be

more geologically active than Earth.

Jupiter's enormous gravity stretches and squeezes lo forcing

it to heat up so it stays molten inside.

We found that lo had eight active volcanoes on it.

The most volcanically active body in the solar system, and

it's just a small moon.

And that was so unexpected.

And it was such a shift in our paradigm about what was

going on in the outer solar system, where it's very cold,

and presumably we thought, very dead.

So in that sense, it characterized for us the sense of

seeing things that we really hadn't thought about and

that was in fact very characteristic

of the rest of the mission.

As lo orbits close to Jupiter, it is

constantly brushing against the planet's magnetic field.

The little moon builds up a huge electrical charge, which

discharges onto Jupiter in a continuous flow of three

million amps, causing storms on the surface of the planet.

The next moon Europa was very different,

but no less surprising.

It had a surface of water.

Ice, frozen as hard as rock.

Underneath this icy crust, scientists believe there are

oceans of warm water.

Further out, the moon Ganymede

was bigger than the planet Mercury.

Ganymede's landscapes of rock and ice reminded Voyager's

geologist Laurence Soderblom of Earth.

Ganymede turned out to be really exciting.

We found a broken surface, complex patterns.

It's kind of a cross between ice flows in the Arctic

and continental drift on the Earth.

And so it's icy crust has been sheared, twisted, broken.

Something we didn't expect.

The last major moon, Callisto, was different again.

Like our own moon, it was covered with craters.

Evidence of a violent past when meteorites

crashed onto it's cold, icy surface.

What Voyager discovered at Jupiter's moons transformed the

rest of the mission.

The first thing that strikes one is

"My lord, everything is different."

So the diversity is overwhelming, because this is a mission

of discovery, this is Captain Kirk, this is really,

in the solar system, seeing really new things.

Io and Europa, there's a twin, a pair there and

there's a pair out at Ganymede and Callisto.

What about the relief from the cracks?

Shouldn't the cracks anneal and flow also?

In order for there to be enough heating.

All of the scientists with exception of me where

atmospheric scientists and astronomers.

And in fact, it wasn't until we really recognized the exotic

variety and diversity of the satellites that geologists

were really added to the Voyager team.

Just rotate it out a little bit.

And in fact, the satellites in my view became

the star of the whole Voyager experience.

Jupiter's moons are a solar system in miniature.

As Jupiter formed, it's immense gravity must have attracted

a cloud of dust and gas from which it's moons were born.

Just as the planets formed around the Sun.

Close to Jupiter are the small, dense active worlds of

Io and Europa.

A mirror of the inner rocky planets,

Venus, Earth and Mars.

Further out, Ganymede and Callisto

are larger, icy worlds.

The giants of the Jupiter system.

Voyager's next goal was Saturn.

Early astronomers believed Saturn was the last planet

in the solar system.

The first to observe the rings, Giovanni Cassini, saw a flat

disc with just one gap.

Scientists hoped that Voyager would reveal clues to the

origin of these mysterious rings.

And this time, after Voyager's success in producing

such powerful images of Jupiter, the press and the

public were queuing up for a glimpse of

the first images of Saturn.

We thought we knew it all.

But once again, we were looking at a

very, very complex situation.

The rings were broken up into many rings.

There were gaps in there.

There were all sorts of dynamical phenomena

that we didn't understand.

So we very, very hurriedly reprogrammed Voyager 2 to take a

much closer look at the rings.

When I began my work in about 1964, I had suggested that

one thing we could do with this particular mission was to

fly between the planet and the rings.

And very fortunately, we didn't do that.

Because as we approached Saturn, we saw that the

region there that we would to have to have flown through

with the spacecraft was filled with more rings.

There was no question that that spacecraft would not have

survived trying to go through that gap.

The imaging team could barely cope with all

the new data coming in from Voyager 2.

They saw delicate rings that were inter-twined and rings

that were held in place by tiny moons called shepherds.

There were strange features called spokes.

Patches of dust particles slightly raised above the rings.

These caught the eye of one young graduate student.

I got involved in the study of the spokes which were these

ghostly features that were seen to come and go.

And it just came to my head to just kind of

categorize the pictures.

Into one pile, I put all of the images that seemed to have

a lot of spokes in them.

Into another pile, I put those images that seemed to have

virtually no spokes at all.

And I made an intermediate category.

And of course, each image was tagged with a time.

And I basically just did an analysis

on the computer of this.

And found that the spokes actually

weren't just sporadic, but in fact,

they came and they went with a certain period.

Carolyn Porco discovered that the spokes

followed Saturn's magnetic field as it

rotated with the planet.

I made my very first scientific discovery

and just knowing that I had found something

that nobody else on the face of the planet

knew at that time was just

such an exhilarating experience.

But where did the rings come from?

A possible answer was discovered when Voyager encountered

Saturn's moons.

A collection of icy worlds scarred by great impact craters

made my meteorites long ago.

The Saturnian system was more like

what we had actually expected.

Small, cold, icy moons which are heavily cratered set of

objects, but there were some real surprises there as well.

The innermost of the large satellites is Mimus.

We found large impacts.

This crater called Herschel,

is a fourth the size of the object.

Nearly large enough to blast it apart.

We find a similar impact crater on Tethys,

the next moon out.

And roughly a third the size of the object.

So it's clear that in the early history, they were

being blasted by things that were large enough to have

torn them apart.

If Mimas nearly got bashed up to bits, then it's very

likely that there were other satellites that did get

smashed up to bits.

And the rings of Saturn probably came from

a satellite that was close in to the planet,

got smashed up.

The debris of the collisional shards got

strewn out into a planetary ring system.

As Voyager moved closer to the planet itself,

it found that Saturn was made of the same gases as Jupiter.

These two worlds of the great gas giants of the solar system

dwarfing all the other planets.

Yet Saturn held mysteries of it's own.

Saturn is smaller and colder than Jupiter.

It generates less heat within and receives

less energy from the Sun.

Yet Voyager recorded even faster winds on Saturn than on

Jupiter, a thousand miles an hour.

How this could happen was a mystery.

And as voyager left Saturn,

there was one final enigma.

Saturn’s largest moon Titan, is the only

moon in the solar system with a thick atmosphere.

Voyager's cameras were unable to penetrate

this orange haze to discover what’s laid beneath.

I found myself alone, in the voyager imaging area

late in the evening, about 10 o’clock in the evening.

And it was just me and the television monitor.

And this was the monitor that showed us all the

tremendous pictures that people were gathered around and

now it was just showing the image of Saturn that

Voyager 1 had as it receded from the planet.

And I was mesmerized by this whole thing thinking

about how human kind had never seen Saturn from

this perspective before, because we have never

been on the other side of Saturn before.

And I was so moved by

me and Saturn alone in this room that

I was completely swept away by the whole thing.

Voyager’s next goal was Uranus discovered just

two hundred years before and still

very much an unknown world.

Would this strange planet, tipped over on its back,

resemble its great neighbours, Jupiter and Saturn?

Even travelling at over 50,000mph, it would take some

five years for Voyager to reach Uranus.

The engineers needed every moment to prepare for there

most difficult challenge yet.

Voyager was planned to operate at one billion miles at

Saturn, it was now being asked to operate at two billion

miles at Uranus, where the sun was very dim.

We had to do several things.

For instance, you have to have much

longer exposures on the camera.

And if you have too long an exposure, the spacecraft's

moving very rapidly, things become smeared.

So we had to lean how to program the spacecraft to

turn it just the right rate so it would compensate for the

motion of the spacecraft.

But when Voyager reached Uranus,

it's cameras found little to photograph.

We had been so spoilt by the glamour and the color and the

intricacies of what we saw in the atmospheres of Jupiter

and Saturn that Uranus was a little bit of a letdown

because it was so bland.

There’s more atmosphere and more haze above the clouds

and so it’s hard to see features.

Even at its closet to the planet,

Voyager revealed little detail about Uranus.

Uranus is different than Jupiter and Saturn in the

sense that it has no internal heat source.

Both Jupiter and Saturn are radiating more energy

than they receive from the sun because there is still

heat inside those planets.

For some reason at Uranus that heat source had been shut

down and was not driving the atmosphere.

So the atmosphere was much blander.

Voyager had found a very different kind of giant.

A world many times smaller and colder than

Jupiter and Saturn.

It was shrouded in different gases.

Mostly methane and ammonia, under which scientists

believed there might lie oceans of water and ice.

What exactly is that stuff?

It's happening here.

If Uranus had been something of a

disappointment, the imaging team found plenty

of surprises in the planet’s moons.

Most striking of all was the tiny moon Miranda.

Miranda looks like a three dimensional jigsaw puzzle,

which we see regions looking like

giant complex race tracks.

Almost as if it's put together by a committee.

There are pieces stuck on the surface that look like they

belong to different planets.

And one idea was, that it was busted apart,

and these core pieces stayed

intact and then they were

glued back together so you get this hodge podge.

Perhaps it was just such a collision

on a much larger scale that knocked Uranus itself over

on its back in the earliest days of the solar system.

From Uranus onwards to Neptune,

some 3 billion miles away from Earth.

The probe would have to take a precise trajectory over the

north pole of the planet to get the best view of Neptune

and its large moon Triton.

The challenge at Neptune was the

most difficult one we had.

We had to know within one second when were going to fly over

the north pole of Neptune.

That was a major navigational challenge.

We had never delivered that kind of accuracy before and if

we were right, it worked and if we're wrong,

we had no second chance.

After 12 years in flight,

Voyager arrived at Neptune.

Brad Smith and his team feared after the

bland face of Uranus, that they'd see little when they

got to the last giant.

They need not have worried.

The final encounter I was able to

witness here at J.P.L.

with my youngest son

and we watched with fascination as the

pictures of Neptune unfolded.

Suddenly things that no one had imagined were there.

Here was a planet that was vibrant with life.

It had its own great spot, the dark spot in this case.

White clouds floating in its atmosphere and these things

unfolded before our very eyes,

and what a wonderful surprise.

Neptune for me was a great surprise.

There was something strange and eerie about Neptune

because here, the last planet,

the sentinel at the outer edge

of our solar system looks like Earth with it's

beautiful deep blue color and its

white clouds floating in the atmosphere.

We were back with a really exciting planet

again at Neptune.

There were fast moving clouds.

Clouds that moved in different directions.

Some of them almost at sonic speeds.

The complexity of the planet’s atmosphere was far beyond

our expectations.

Neptune turned out to have the strongest

winds of all.

Here in the furthest extremes of the solar system

where the sun barely penetrates the last giant

defied all expectations.

You might expect that the further you got from the sun,

where there is less energy to drive the winds,

the winds would be slower.

Winds on Jupiter are already hundreds of miles per hour.

It turned out rather than seeing slower winds,

we found faster winds.

We found winds over a thousand miles per hour at Neptune.

We now understand why that's the case.

And that is if you have enough energy, it creates a

lot of turbulence and that slows the wind down.

At Neptune there was so little energy that the wind

basically got started and would just go and go and go.

Made of the same gases and ices, Neptune’s

atmosphere was moving much faster than Uranus’s.

The last two giants were very different from their

more massive cousins.

Uranus and Neptune are not gas giants but ice giants.

From Earth, nobody had seen a full set of rings at Neptune.

But some scientists believed they had seen incomplete

segments of a ring, which they called arcs.

By the time we got to Neptune, I was

leading the small group of individuals

on the imaging team who were

responsible for the rings and the ring arcs.

In fact, there was some people on the Voyager imaging team

who just completely doubted the existence of these things.

They thought we were crazy.

They thought we were wasting precious spacecraft resources.

And so it was very gratifying to finally see that one image

come down were we captured, finally caught them in the act,

the Neptune ring arcs.

So it was a tremendous achievement.

Neptune is indeed surrounded by ring arcs.

How they got there and why the ring is incomplete

is not yet known.

The impossible mission was almost over.

Neptune’s moon Triton was the final encounter.

Triton is a large moon, it's about the same size as the

planet Pluto actually.

So if it were out in orbit around the sun,

we would call it a planet.

But it's in orbit around Neptune.

But unlike all the other satellites which orbit in the

same direction as the planet rotates, Triton is in

retrograde orbit.

It's going around Neptune backwards, which told us it was

not likely formed around Neptune,

but had been captured by Neptune.

Triton is a moon that might've been a planet,

but it strayed too close to Neptune

and was caught by it's gravity.

Triton turned out to be one of the strangest

worlds encountered.

This is too much, this is much too much.

Oh god, look at the tire tracks.

Right, there you go.

Triton was a world unlike any we had seen before.

It was the coldest surface we'd seen in the solar system,

40 degrees above absolute zero.

So cold that nitrogen, which forms most of the atmosphere

on Earth, is frozen solid ice.

And the polar capsules on Triton are frozen nitrogen,

not frozen water.

Even so, we found geysers on the surface of Triton.

Nitrogen geysers miles high.

So even at the very deepest part of our solar system,

there is geologic activity.

It is everywhere, the solar system is alive, evolving

and that’s what makes it so exciting and makes it,

so much to learn.

Voyager had survived to reach the extremes

of the solar system.

And reveal not just the giants themselves, but whole systems

of rings and moons unlike anything imagined.

As the planets moved out of there alignment,

Uranus and Neptune once again drifted out of our reach.

It's unlikely that they'll be visited again in our lifetime.

But Voyager was not the last mission to the gas giants.

In 1994, a probe named Galileo returned to

Jupiter and its moons.

It found that lo's surface had been covered by fresh

eruptions of sulphurous lava.

Europa which had looked so smooth, turned out to be covered

in great ridges and chasms.

Fresh detail was revealed in Ganymede's alien landscapes.

And there was more destruction than had been

imagined on Callisto.

In October 1997, a mission called Cassini

set off for Saturn.

It will spend four years sending back high resolution images

of the great planet, it's rings and it's many satellites.

Head of the imaging team is Carolyn Porco.

We are interested, for scientific purposes in taking

images of Titan and all the satellites too.

So how many images do you think you'll need in that block?

Four is what we nominally talk about.

Four images?

Mm, hm.

In 30 minutes.

Mm, hm.

OK.

We have designed the camera system specifically,

among many other things.

We’ve designed it see down to the surface of Titan,

which or course is something we weren't

able to do on Voyager.

And we'll be able to see things

that are on the scale of office blocks.

We'll be collecting data from Cassini at least for

a period of four years.

So we’ll have a chance to monitor changes,

and you know, it'll be a new era.

But, it will never have the same feeling

or even, even significance,

historical significance as Voyager had because

that experience can never be duplicated.

The next awards are the exceptional

scientific achievement medal.

The first award goes to Gary Flandro.

For seminal contributions to the design and engineering

of missions, including the grand tour of opportunity

for the epic Voyager explorations.

The views that were achieved there at each of those

outer planets far exceeded any expectations,

but it was a ghostly feeling of having already being there.

Myself flying that mission in my mind in the 1960’s.

Work all started right up in that office.

Is that right?

That’s where I was.

Building 180’s where you worked?

Sat out and looking out that window, through those trees,

and up towards the sun and I said

"We could do this, four planets in one flight."

With the planets behind it, Voyager carried

on to search for the very edge of the solar system.

Where the sun’s influence runs out,

and interstellar space begins.

The Voyager mission is not over.

We hope we can continue listening to it for at least

another 20 years before we finally

lose power on the spacecraft.

In 2015, Voyager 1 will be 130 times as far

from the sun as the Earth.

About 12 billion miles from the Earth and perhaps,

in interstellar space for the first time.

So we listen to the two Voyager spacecraft everyday looking

for some signal that we're getting close

to interstellar space.

The greatest Voyager in history

is still travelling.