All language subtitles for National.Geographic.A.Travelers.Guide.To.The.Planets.S01E05.Neptune.and.Uranus.720p.HDTV.x264-DHD

NARRATOR: Got time for
a 24-year vacation?

Then consider a journey to the
most distant planets

of our Solar System.

CAROLYN PORCO: The rest of the
Solar System beyond the Asteroid

Belt is really where it's at.

NARRATOR: They are two
giant worlds of icy gas.

And one of them
has a funny name.

HEIDI HAMMEL: I pronounce the
planet's name 'YOOR-a-nus'.

NARRATOR: From orbit, Uranus
appears sedate and calm.

But why is the
planet on its side?

And Neptune: The
second blue planet,

and the last world
in our Solar System.

So far from the Sun, you
wouldn't expect much to be

happening here.

But something is
driving its wild winds,

the fastest in the Solar System.

And what became of
its Great Dark Spot?

HEIDI HAMMEL: So this planet
just changes its spots.

Leopards don't,
but Neptune does.

NARRATOR: Uranus and
Neptune: The 'ice giants'.

Strap yourselves in for an
incredible voyage to the most

remote and intriguing
planets of all.

There has never been a better
time to boldly go where no human

has gone before to follow in the
footsteps of our robot pioneers

and visit the planets
of the Solar System.

Ever wanted to be an astronaut?

Imagine heading into the
Ice Zone, the frigid,

dark realm beyond
the orbit of Saturn.

To travel here means undertaking
a voyage of epic proportions.

Think of this as your
personal travel guide to

the outer Solar System.

First stop Uranus.

At first glance, the seventh
planet from the Sun appears as

an unmeasurable ball
of green-blue fog.

But slip below Uranus' icy
veil and you encounter a world

seemingly without end...

because this is a planet
made almost entirely of gas:

hydrogen, helium and a
splash of methane that gives

the planet its color.

TORRENCE JOHNSON: It's actually
very difficult to describe to

people what it feels like in
the interior of these gas giant

planets because it's so far
from our terrestrial experience.

NARRATOR: The third-largest
planet has at least 13 rings.

But unlike the broad bands of
Saturn, these are thin and dark.

No one's quite sure
how they're formed,

but they could be the result
of collisions between its small

army of at least 27 moons.

But Uranus' most striking
feature is its lopsided tilt.

It's the only planet in the
Solar System to orbit on its

side, resembling
a giant bullseye.

How did it end up this way?
The answer may surprise you.

HEIDI HAMMEL: I'm fascinated by
Neptune and Uranus because we

know so little
about these planets.

We've only ever had one
spacecraft visit them and

it was a very brief flyby.

NARRATOR: Astronomer Heidi
Hammel is driving to the ice

giants -- well about as
close as you can get to

them on planet Earth.

HEIDI HAMMEL: The most exciting
thing about Uranus is that it's

completely tilted
over on its side.

Its atmosphere changes
radically,

depending on the season.

And it has a really
interesting thin ring system.

So that's the cloud and these
of course are the rings.

It's a nice image of Uranus.

NARRATOR: Although separated
by 1.6 billion miles,

one of the world's highest
telescopes is watching the

planet spring into life.

HEIDI HAMMEL: Uranus has been
going through a very special

season that we call 'equinox'.

The north polar part that's
coming into sunlight for the

first time in two decades is
turning on with all kinds of

dynamic cloud activity, none of
which was expected or predicted.

So it's very exciting to get
this data and basically be

rewriting text books about
the Uranus system right now.

We're very happy astronomers.

NARRATOR: For the first time,
this far-flung outpost is being

seen in a new light.

And when it comes to image,
it's not a moment too soon.

That's because, for most of
us, Uranus is the butt of

a big cosmic joke.

ANDY INGERSOLL: I
pronounce it 'YOOR-a-nus'.

I think people are
embarrassed about 'Your-ANUS'.

CAROLYN PORCO: 'YOOR-a-nus'.
Yeah.

HEIDI HAMMEL: I pronounce the
planet's name 'YOOR-a-nus',

which is very likely closer to
the original pronunciation of

the name of the god
after who it was named.

NARRATOR: If you think 'Uranus'
is a funny name for a planet,

then you may prefer its
first name, 'George'.

Discovered by William
Herschel in 1781,

he christens his new find
'Georgium Sidus' after the king

of England, George the Third.

But the custom of naming planets
from ancient mythology prevails,

and 'Planet George' is no more.

It's very likely that Uranus
would have remained nothing more

than a green-blue blotch at the
end of a telescope if it wasn't

for a really bright
rocket scientist ...

and a little bit of luck.

GARY FLANDRO: A lot of people
were saying back in the 'sixties

that it would be impossible
for us ever to explore

those distant planets,
too far away.

NARRATOR: As an intern at the
Jet Propulsion Laboratory in

California, Gary Flandro is
given the task to investigate a

journey to the outer planets.

GARY FLANDRO: So I started
drawing pictures of

the Solar System.

And in that process I notice
that all of the outer planets

turned out to be about the same
alignment relative to the Earth

in the late 'seventies.

So I saw that I could almost
draw a ruler between Jupiter,

Saturn, Uranus, Neptune.

Pluto was not cooperating, but
that seemed not to be a worry.

NARRATOR: This mathematical
sleuth work reveals a rare

window where the planets are
perfectly aligned for a visit.

ED STONE: There's an opportunity
every 176 years for a single

spacecraft to fly by
all four giant planets.

That was 1977 and so we
created the Voyager mission

to start on that journey.

VOYAGER FILM NARRATION: A
complex package of experiments

called Voyager is designed to
take the first thorough close-up

look of the giant outer planets.

NARRATOR: In an extraordinary
feat of engineering,

teams build two spacecraft
in just 12 years,

and pushed the existing global
network of ground

stations to new heights.

TORRENCE JOHNSON: The outer
Solar System is called 'outer'

for a reason.
It's a long way away.

CAROLYN PORCO: The rest of the
Solar System beyond the Asteroid

Belt is really where it's at.
And so that's what Voyager did.

Voyager showed us
what was out there.

NARRATOR: Onboard, there's
even a gold record containing a

greeting from Earth, should
the spacecraft encounter

any friendly aliens.

VOYAGER RECORDING: Hello from
the children of Planet Earth.

ED STONE: We knew the Voyagers
were going to be the first to

reach interstellar space.

So we thought that this was sort
of an announcement from Earth

that we were now able to send
a message away from our Solar

System into orbit around the
centre of our own galaxy.

NARRATOR: Launched a
few weeks apart in 1977,

the twin Voyager spacecraft
embark on their epic journeys,

known as 'The Grand Tour'.

CAROLYN PORCO: It was a
first, it was historic.

Just being part of
the whole mission,

being part of this
tremendous enterprise,

the first time in human history
we are seeing these bodies

up close was a thrill.

NARRATOR: What would it be like
to follow in the footsteps of

Voyager, to experience one of
the greatest journeys

in space exploration?

Planning a vacation to Uranus?

Time to study up on what
you're about to get into.

63 times larger than the
Earth, here you'd be lucky to

celebrate a single birthday.

The planet takes 84 years to
make its way around the Sun.

Uranus, and sister Neptune,
are known as the 'ice giants'

because of their frigid
outer atmospheres,

super-cooled to a minus
355 degrees Fahrenheit.

But the biggest, most obvious
feature about Uranus

is its crazy tilt.

However, it wasn't
always this way.

TORRENCE JOHNSON: The
traditional explanation was that

while Uranus was forming it may
have been hit by a larger chunk

of accreting material than
normal and actually knocked it

over on its side.

The problem is, when you do the
maths on this, it doesn't work.

It's very, very difficult to get
a large enough body traveling

fast enough to be very credible
at knocking

Uranus over on its side.

NARRATOR: Rather
than being pounded,

it's now thought that Uranus may
have been swept off its feet by

the gravitational tugs
of its giant neighbors.

TORRENCE JOHNSON: Uranus' tilt
actually results from some

rather complicated interactions
with Saturn and Neptune

and Jupiter even.

All of these planets do have
gravitational affects on one

another and the affects are more
subtle than we used to think.

And it's dynamics, not a big
smack in the face from

a large impacting planetesimal.

When Voyager journeys to the
outer Solar System in the 1970s,

it beams back astounding
images of Jupiter,

Saturn and many of their moons.

ED STONE: Well that's
the wonderful thing

about the Voyager mission.

We saw so many things for the
first time and they were all so

different, so diverse
and distinctive.

TORRENCE JOHNSON: Being there
when the images are coming in

makes you feel like
you are on the bridge of

the Starship Enterprise.

Because you really
feel like you're there,

those are just your sensor
screens and you are getting

reports back from these
alien worlds that you are

taking a look at.

CANDY HANSEN: Who could
ever have enough pictures

of Saturn's rings?

NARRATOR: So what do Voyager's
cameras reveal of Uranus,

the lopsided planet?

TORRENCE JOHNSON: Well Uranus
was a real enigma for us.

So we didn't know
what to expect.

NARRATOR: In 1986, after a
decade of traveling through

space, there are great
expectations for the seventh

planet from the Sun.

BONNIE BURATTI: From the
Earth it looked kind of bland.

And quite frankly, from Voyager
it looked kind of bland too.

HEIDI HAMMEL: The
images of Uranus were

a little bit disappointing.

ED STONE: It's a very bland
planet with very few clouds.

GARY FLANDRO: Not much
going on at Uranus.

NARRATOR: These are the
very first images of Uranus,

taken from Voyager 2.

The planet appears as still as
a pond with no cloud

detail at all.
And it's silent.

JACK CONNERNEY: We did not hear
a whisper from Uranus before

the Uranus encounter.

NARRATOR: Unlike Jupiter, whose
magnetic field roars across the

radio waves, at first
Uranus doesn't make a peep.

JACK CONNERNEY: Part of that was
because the radio source was on

the other side of the
planet where the strong

magnetic fields are.

And they were beamed
away from the spacecraft.

NARRATOR: Voyager discovers
that Uranus' magnetic field

is wildly off kilter.

Planetary magnetic fields
require the movement

of charged particles.

On Earth, this occurs
in our molten iron core.

So what's driving
Uranus' magnetic field?

There's more going on
here than meets the eye.

Just what lies below
Uranus' veil of clouds?

To find out means clearing your
calendar for the next 24 years

and surviving a
flight from hell.

You've escaped the clutch
of Earth's gravity,

the first step on your voyage
to the outer Solar System!

Now, the seatbelt
sign is off, but your

problems are just beginning.

Zero gravity may look fun, but
when it comes to human biology,

we're simply not designed to be
in the weightlessness of space.

VOLKER DAMANN: If there is no
gravity then there is no need

for the heart muscle to
pump the blood upwards,

so the heart muscle doesn't
need to work as hard,

so it's de-conditioning.

The same happens
with all the muscles.

If you are not working and
exercising and working against

the drag of gravity,
you get de-conditioning.

NARRATOR: From this
control room in Germany,

a medical team scrutinizes
the health of the European

astronauts onboard the
International Space Station.

VOLKER DAMANN: The
astronauts workout roughly

two hours per day.

It's a mandatory physical
exercise that we prescribe.

Some people like more
to ride the bicycles,

others like to
use the treadmill.

NARRATOR: Zero
gravity for 24 years?

That two-hour daily workout
will soon get pretty tedious.

The fact is, no one really knows
what effect two dozen years of

weightlessness will
have on the human body.

No one's ever been
in space that long.

KEVIN FONG: Human missions to
the outer planets are going to

take years, even
more than decades.

And none of these places
support life on their own.

You're going to take everything
that you need with you,

you're going to take your
food, your water, your light,

your heat, your power,
your atmosphere and that's

a tricky thing to do.

NARRATOR: And the one
item you'll need more

than anything is water.

KAREN PICKERING: If you were
just to put everything you need

in a box and take it to
space with you for a year,

about 90 percent of the
mass you need is water.

NARRATOR: To solve the problem,
NASA has been working on its

recycling systems.

But it may not suit
everyone's taste.

KAREN PICKERING: We take
waste water strains from a

variety of sources.

We take hygiene water from your
showers, washing your hands,

brushing you teeth,
urine, of course.

And then we can choose several
different processes to bring

that waste water clean enough
that we can drink it again.

The clean water tastes just like
water you'd buy in the grocery

store but it's distilled so it
doesn't taste as good as your

water from the tap because
there is no minerals in it.

But it doesn't taste
like waste water,

like you know
where it came from.

NARRATOR: So with your thirst
quenched, you're on your way.

Sit back and relax for
the next ten years.

So you've survived the
decade-long journey to Uranus.

Hopefully, you haven't put
on too many pounds from the

10,000-plus inflight meals.
Time to start exploring.

From orbit, Uranus
gives little away.

But plunge below its
placid-looking clouds and you

encounter a world
that's anything but.

HEIDI HAMMEL: So let's imagine I
was riding an atmospheric probe

that's being sent down
into the planet Uranus.

NARRATOR: Open your spacecraft
window here and you'll quickly

feel where the ice-giants
get their name.

In the upper atmosphere,
frozen-crystals of methane mix

with hydrogen and helium.

HEIDI HAMMEL: We might pass some
of these towering anvil clouds

that we know are there.

And as we looked at those we
would look for the lightning,

we would listen for the thunder
that would accompany them.

NARRATOR: Freefalling here
is like descending into a

giant green gelato.

But the deeper you go,
the thicker and hotter

the atmosphere.

Temperatures heat up to
thousands of degrees,

heat leftover from when
the planet formed.

ED STONE: Eventually, the
pressure just builds and the gas

becomes basically a
fluid or a liquid.

And there's no real transition,
it's just a continuous increase

in pressure and density.

NARRATOR: Keep descending and
you'll soon start to boil in a

seemingly bottomless
sea, more than

2,000 times deeper than
the Pacific Ocean.

Somewhere down here, a little
more than halfway to the

planet's center, Uranus'
lopsided magnetic field

flutters into life.

JACK CONNERNEY: If you could
see down to the surface of the

dynamo core, where the
field is generated,

what you might see is parcels
of fluid moving about.

And they're generally so
conductive that those parcels of

fluid would drag
field lines with them.

NARRATOR: Why Uranus' magnetic
field is generated here,

and not in the core,
no one really knows.

No person or robot has
ever been down here.

HEIDI HAMMEL TO CAM: If we could
get even further we might get to

a core, but we're not sure.
Isn't that interesting?

We aren't sure if
Uranus has a core.

NARRATOR: Down here, one thing
is certain: with a planet-load

of water and gas on your back,
and in temperatures of more than

4200 degrees Fahrenheit no
life, or robot, will last long.

TORRENCE JOHNSON: There would
be no chance of surviving

under those conditions.

A probe going into the
atmosphere would eventually

evaporate and would become
part of the atmosphere that

it was studying.

NARRATOR: Not enthused about the
prospect of being crushed and

boiled alive by a
giant ball of gas?

Don't worry, there's still
plenty more to see and do.

Cruise above the
skies of Uranus,

and take your pick of 27
moons, most named after

characters from Shakespeare.

HEIDI HAMMEL: If I were to take
a tourist trip to the Uranus

system, I would go to Miranda.

NARRATOR: Only 290 miles across,
moon Miranda is about as wide as

the state of New York.

But the geography here is
stranger than anything on Earth.

TORRENCE JOHNSON: And it is
an interesting sort of jigsaw

puzzle moon.

It looks like it has been put
together by a potter without

paying too much attention
to his materials.

It has got chunks of
this and chunks of that,

that sort of look like
they are slapped together.

And frankly, we still don't
really understand

Miranda too well.

NARRATOR: When Voyager
first spots Miranda,

no one is sure
what to make of it.

BOB PAPPALARDO: When the
images came back of Miranda,

the first ideas were that
Miranda was somehow shattered by

a huge impact, broke up
and came back together.

NARRATOR: But now scientists
think that the moon may be

caught in the middle
of a cosmic makeover.

BOB PAPPALARDO: In the early
stages of a satellite's history,

the satellite is
differentiating.

The rocky bits are falling to
the center and the icy bits are

lower density and
moving outward.

And so maybe that's
what we're seeing.

Miranda sort of frozen in
a state of differentiation.

NARRATOR: The result: a
part-finished lunar construction

zone, with some pretty
impressive sites to visit.

TORRENCE JOHNSON: Miranda's got
some spectacular ice cliffs on

it that you could sit on the
top of and look down for

five or six kilometers.

NARRATOR: Think the Grand
Canyon is impressive?

On Miranda, these cliffs are
at least three times higher.

BOB PAPPALARDO: If you
were to jump from it,

because of the very, very
low gravity of Miranda,

it would take minutes to slowly
fall down to the surface.

TORRENCE JOHNSON: With this nice
blue fuzzy ball of Uranus in the

background, it might
be pretty scenic.

NARRATOR: And while you're here,
it's hard to ignore Uranus'

other tourist attraction,
its collection

of 13 razor-thin rings.

HEIDI HAMMEL: Uranus' main rings
are very tightly confined with a

lot of space in between them,
sort of like a series of hula

hoops, increasingly large hula
hoops moving away from Uranus.

NARRATOR: How these rings
form, no one's completely sure.

But they could be the result
of a cosmic demolition derby.

BONNIE BURATTI: The five major
satellites of Uranus are in

pretty regular orbits
and they are stable.

But some of the other objects,
especially the outer satellites

of Uranus, scientists have been
working on computer models that

show they do frequently collide.

And if they get too close to
Uranus, they could break apart.

And of course Uranus does have
very complex family of rings

that we believe are these
broken up satellites.

NARRATOR: For the planet
that's always been the butt of

everyone's joke, perhaps it's
only fair that it has the last

laugh.

That's because Uranus'
best view is its rear end.

LINDA SPILKER: As we were
flying out from Uranus,

we were looking back and looking
at the rings we call 'high phase

angles', equivalent if you have
a dusty windshield and you drive

into the afternoon Sun, the
dusty particles light up.

So too in the Uranus system.

I remember sitting there
as that picture came down,

line-by-line and played
out, and just the joy that,

'Oh my goodness, we didn't know
there was something quite so

spectacular to see
there at Uranus.'

NARRATOR: Take a good last look,
as there's nothing more to see

for three more years...

until you arrive at Neptune.

Make sure you have
plenty to keep you busy;

being cooped up in a
tin can is sure to

play tricks on your mind.

KEVIN FONG: Out in space,
separated by such great

distances, you need to start
thinking about the psychology of

the space environment.

You're going to
be in an enclosed,

confined environment
with almost no privacy.

Death is always going to be just
a half-thickness away and you

have to start thinking about how
to stop your crews going crazy.

ASTRONAUT: Oooh!

NARRATOR: The possibility of
going crazy is something these

space travelers know all about.

ESA OFFICIAL: Congratulations
to the explorers,

to the mission organisers
and the scientists.

NARRATOR: The heroic welcome is
to celebrate their return from a

105-day space mission.

Only thing is, they
haven't traveled an inch.

SIMONETTA DI PIPPO: The Mars 500
program is a simulation project

of a mission to Mars.

What we would like to do is
to simulate the time delay,

the confinement, the
psychological and

physiological aspects.

NARRATOR: Sealed away in
this Moscow warehouse,

the crew lived every day
as if they were on a long-haul

space flight for real.

Watching closely - a team of
psychologists and doctors who

monitored every aspect
of their mental health.

OLIVER KNICKEL: It was not
always easy to stay in such a

confined area for
such a long time.

So, you always felt
kind of limited,

since the space is just limited.

You didn't have the sunlight,
you didn't have the nature.

So this had quite an
impact on the crew.

NARRATOR: The psychological
effects from this mission of the

mind are still being analyzed.

NARRATOR: No one seemed to
go crazy on this mission.

But on a voyage
to the ice giants,

if the isolation doesn't make
you insane, the menu might.

OLIVER KNICKEL: In order
to keep us healthy,

and we hardly had any
fresh fruits or vegetables

we ate this baby food here.

Which might not be the usual
food you have in your usual

life, but at least
it's kept us healthy.

And I didn't even think
it tasted too bad.

NARRATOR: 105 days eating
baby food

is certainly an achievement.

But who's going to
do that for 24 years?

Moving out from Uranus is
its ice sister, Neptune,

another mysterious
ball of frigid gas.

And out here, there's proof the
Solar System still has a few

incredible tricks up its sleeve.

On the approach to Neptune,
be prepared for a surprise.

Because at the end of the Solar
System is a reminder of home: a

second blue planet.

CAROLYN PORCO: Unlike Uranus,
Neptune was immediately

beautiful.

Especially when we started to
produce color pictures because

it had this blue-green
atmosphere and these white

clouds floating
in the atmosphere.

So you couldn't help, at
least I couldn't help but

be reminded of the Earth.

NARRATOR: At 30 times the
distance of the Earth to the

Sun, the star appears not
much more than a glimmering

point of light.

Out here, the days pass quickly,
each 16 Earth hours long.

But you'll need a thick
calendar, with around

90,000 days to a Neptunian year.

That's 165 Earth years
to orbit the Sun.

Like its neighbor, Neptune is
a giant ball of hydrogen and

helium, its color courtesy
of a bit of methane.

But it's so blue here, that some

other chemical mixture is at
work.

HEIDI HAMMEL: In fact, there's
something in the clouds of

Neptune that is causing its
vivid blue color and we don't

know what that is yet.

It's one of the mysteries
that we're trying to solve by

studying Neptune
with our telescopes on

the ground and in space.

NARRATOR: And that's not the
only mystery: Something is

driving Neptune's wild winds,
the fastest in the Solar System.

And why do Neptune's
spots vanish almost as

quickly as they appear?

TORRENCE JOHNSON: As we
were approaching Neptune,

and it was getting larger and
larger on the TV screens in the

project area, the thing that
really got us going very

rapidly, we noticed that Neptune
had something that Uranus

didn't, which was a big
spot in its atmosphere.

ANDY INGERSOLL: Voyager
saw several spots,

the biggest one we imaginatively
called 'The Great Dark Spot.'

TORRENCE JOHNSON: It kind
of was like watching a blob of

ink in swirling water.

NARRATOR: About
the size of Earth,

the Great Dark Spot is
actually a massive hole,

a window to the
darker clouds below.

HEIDI HAMMEL: So a swirling
storm that cleared out a hole in

the clouds allowing us to
see down to deeper layers.

It didn't give the
appearance of being stable.

It sort of gave the
appearance that at any moment

it could fall apart.

And so we weren't all
that surprised when within

five years it had disappeared.

NARRATOR: In 1994, when
NASA turned Hubble,

its orbiting telescope,
towards Neptune,

its Great Dark
Spot had vanished.

HEIDI HAMMEL: So this planet
just changes its spots.

Leopards don't,
but Neptune does.

It dramatically changes its
spots on timescales of

just five years.

That was a surprise that
Neptune changes so quickly,

it's a different kind of planet.

NARRATOR: Since then other
spots have come and gone.

No one's sure why, but it could
have to do with Neptune's wild

equatorial winds.

Take a leap into
Neptune's atmosphere,

and you'll be surfing the
fastest skies in

the Solar System.

This wind tunnel in Los Angeles
is barely a ripple of air

compared to Neptune's winds.

Because on the last planet
in the Solar System,

winds roar around the equator at
nearly twice the speed of sound.

ANDY INGERSOLL: What
drives the weather?

There's two things.

One is the Sun, kind
of like the Earth,

although the Sun is
pretty weak at Neptune.

And then Neptune has
some leftover heat.

And the heat comes
out as warm gas.

ANDY INGERSOLL: When
the planets formed,

all this material came
crashing together.

And that crashing
together generated heat.

And some of that heat
is still there buried

down inside Neptune.

And when the heat inside Neptune
comes out you get updrafts and

that drives the jet streams
and the whole thing is

a big weather machine.

NARRATOR: With no bulky
land masses to stop them,

Neptune's jet streams
keep going and going.

CAROLYN PORCO: It could
be that the winds on Neptune

just grew over time.

They kind of developed
over time to be very rapid,

even though the energy
that started them

off was very feeble.

NARRATOR: But what's underneath
the sheath of Neptune's

ferocious winds?

Does the planet that takes its
name from the god of the ocean

live up to its reputation?

Can you really set sail
on a Neptunian sea?

HEIDI HAMMEL: Just about
everything about Neptune and its

system relates to
water in some way.

NARRATOR: One thing most experts
agree upon is that Neptune has

plenty of water.

However, exactly what form
it takes, is less certain.

But it's something almost
everyone has an opinion on.

ANDY INGERSOLL: There's a lot of
water on Neptune but it's down

deep and it is probably too
hot to be a liquid right now.

NARRATOR: Down here it's like
soaking in a planet-sized steam

room, where gas is
squeezed into a liquid.

TORRENCE JOHNSON: Not an ocean
but sort of a strange mixture of

an atmosphere heavily laden
with denser and denser liquid

materials as the
pressure got higher.

HEIDI HAMMEL: If there were an
ocean on Neptune it would be

very deep inside the planet.

It would not be on the
outer-part of the planet where

we could put a spacecraft
or a boat like this.

NARRATOR: On Earth, the
combination of heat and water is

essentials for life to exist.

So what are the chances of
meeting any locals here?

FRAN BAGENAL: You've got some
warmth, you've got hydrocarbons,

you've got water.

You could well have
developed some life form.

Somehow I suspect it's not
going to be particularly

sophisticated.
But who knows?

Maybe there are big stingrays
swimming around deep

in the ocean?

NARRATOR: Not a fan of the deep?
Don't worry.

Like its icy neighbor, there's
plenty more to see and do

without getting
your spacesuit wet!

CAROLYN PORCO: Those of us who
are interested in rings got

teased mercilessly as we were on
approach to Neptune because it

wasn't clear if Neptune
had rings per se.

They were just impartial
arcs is what the mindset was,

that was our idea.

And finally when we got there
we did find Neptune had defuse

rings, complete rings but also
these rather opaque ring arcs.

NARRATOR: Neptune's rings may
not be the prettiest in the

Solar System, but they're
still worth a snapshot or two.

HEIDI HAMMEL: Neptune's
rings are clumpy.

There are sections that are
very bright and sections

that are very thin.

LINDA SPILKER: These
particles are very dark.

There might be water ice
mixed with some organics,

or just organic material.

They only reflect a few percent
of the sunlight that they

receive, so very, very dark.

Very different from
Saturn's bright icy rings.

NARRATOR: It's thought these
gangly ring arcs are kept in

check by the gravity
of tiny satellites,

known as 'shepherd moons'.

CAROLYN PORCO: This was
something in fact I was

personally involved in, in
trying to understand how the

arcs were there.

And we found that they were
being anchored by one of the

moons, the moons that
in fact Voyager had found

in the ring region.

LINDA SPILKER: As a ring
scientist I'd be very interested

in collecting some
souvenir ring particles.

And so I would try and get a
space worthy jet ski equivalent

and then go to explore
the rings of Neptune.

NARRATOR: Neptune's ring
arcs are one of a kind

in the Solar System.

But the real show-stopper here
is Neptune's moon, Triton.

Just getting to Neptune means
putting your life on hold for

24 years. That's a lot of
inflight movies.

But what if you could
literally put your life on ice?

Suspended animation has
long been a favorite topic

of science fiction.

Like the clients of this
cryogenic facility in Arizona,

the space traveler of the
future could well become

a time traveler.

MARK VOLKER: The purpose is
to hold them in a state of

suspended animation
until such time that

they can be reanimated.

NARRATOR: Inside these canisters
are the frozen remains of 88

people, all hoping at for
a second shot of at life.

The problem with cryogenic
suspension is that it's not very

user-friendly: you
have to die first.

But for the space
traveler of the future,

that could all change.

MARK VOLKER: So you could put
them in a state of suspended

animation, put them on a
spaceship and months or years

later wake them up at the
destination so they wouldn't

have to be alive and conscious,
eating and doing all the other

things that you have to
do when you're alive.

NARRATOR: Already, scientists
are working on ways to

slow down metabolism.

CHENG CHI LEE: It's about two
hours after we have injected the

AMP and the mice now are in
a deep hypothermic state.

NARRATOR: The mice who
don't normally hibernate,

are injected with a nucleotide
that inhibits thermoregulation.

A state of hypothermia
is then induced by lowering

their core temperatures.

After around two hours,
the rodents stir.

CHENG CHI LEE: So what
happens now is the mice is now

in an arousal state.

NARRATOR: They're a
little sleepy at first,

but completely unharmed.

CHENG CHI LEE: I hope that
within ten years we can run some

of this in a human trial,
somewhere down the road.

NARRATOR: Could this really
be the future of space travel?

If we're to undertake the
incredible journeys to planets

like Neptune, suspended
animation may be the only

practical solution.

But will a trip out here really
be worth the time and fuss?

Well, some planetary
scientists think it could be,

if only to visit Triton.

CAROLYN PORCO: Well I remember
the night we flew over Triton.

We stayed up all night because
I think the flyby happened early

in the morning.
And it was just so unusual.

BOB PAPPALARDO: Oh boy, Triton
is an extremely complex moon

that we understand only in part.

NARRATOR: The largest of
Neptune's 13 known moons,

Triton covered in a
thin layer of ice,

its surface rippled and textured
with features seen nowhere else.

BOB PAPPALARDO: Triton has
pits on part its surface that's

called 'The Cantaloupe Terrain',
because looks a lot like the

surface of a cantaloupe.

BONNIE BURATTI: The other
interesting thing about Triton

is that it has a violent past.

It was almost certainly
captured by Neptune.

And the reason we are certain
that it was captured is that it

was rotating, it
is going around Neptune

in the opposite direction.

NARRATOR: And hiding in these
fuzzy pixels is Triton's biggest

party trick of all.

Voyagers' camera captures
geysers that shoot

high into the air.

CAROLYN PORCO: It was found that
there were jets coming off the

polar cap of Triton.

And these things were going
some 15 kilometers, or 10 miles,

into the air and then taking
a 90-degree turn as they hit a

prevailing jet in this
very, very thin atmosphere.

BOB PAPPALARDO: We're not sure
if these plumes are powered from

the internal heat
engine of Triton,

or are they actually powered by
the very weak and far away Sun?

Which might be causing some
local evaporation

to make these plumes.

NARRATOR: These are Triton's
ice volcanoes that purge an inky

cocktail onto the
gleaming surface.

HEIDI HAMMEL: When we see black
stuff in the outer Solar System

we think 'organic material'.

Organic does not
mean life or plants,

organic in our talk means
'carbon', 'carbon-bearing'.

BONNIE BURATTI: This is, these
are the building blocks of life.

So we think that that dark
material may be pre-biotic

chemistry going on.

Not life itself but
the precursor to life.

CAROLYN PORCO: So here we find,
even our last port of call,

Triton, you know,
cold, cold, cold body.

And yet there is this
activity going on.

NARRATOR: So you've finally made
it to the outer Solar System,

following the epic
journey of Voyager 2.

After 12-years of traveling,
what do you do on a short stop,

before turning around
and heading back home?

BONNIE BURATTI: Well if I were
going to the outer Solar System,

going to Uranus, I think first
of all I think I'd want to orbit

Uranus a couple of times
just to take in those rings.

Because I think that rings are
one of the most beautiful sights

in the Solar System.

TORRENCE JOHNSON: I would go
picnicking on Triton and I'd

make sure that I took some
really warm clothes with me and

some binoculars because sitting
on Triton and looking at this

beautiful blue Neptune hanging
up there would be quite a trip,

actually.

CANDY HANSEN: And then I'm sure
I would sit waiting for Old

Faithful to go off, however
long that was going to take!

HEIDI HAMMEL: By looking at
the outer planets in our Solar

System we can learn
about planetary systems.

And I think that Uranus and
Neptune have stories to tell us

if we can only
hear their stories.

NARRATOR: They're the ice
giants of the Solar System: Two

fathomless worlds, impossibly
remote and unimaginably hostile.

Uranus the planet with the funny
name, but with hidden beauty.

And Neptune a seemingly watery
world with a spouting moon.

It's unlikely humans will
venture out here anytime soon.

Until we do, who knows
what other secrets await

discovery in the ice?

That's the beauty of
traveling the Solar System;

it's full of surprises.

AtZLIT 2010.