NARRATOR: It is the showstopper
of our solar system. Basking in its own glow,
it seduces all admirers. However, it is a beauty
with a mean streak. It's a massive, frigid, ball
of gas surrounded by icy rings, hurdling at 40,000
miles an hour. It is a planet of
violent weather, with a polar storm bigger than
the United States of America. Saturn has some of the
most powerful weather in the solar system. The lightning can be a
million times more powerful than lightning here on Earth. NARRATOR: But its moons
are even more exciting. JOHN SPENCER: The
geysers on Enceladus are erupting water vapor
hundreds of miles into the air because of much
lower gravity there and the fact there's no
atmosphere holding them in. NARRATOR: Another
has an atmosphere with oceans and mountains. Could life exist on
one of these moons? "Saturn-- Lord of The Rings." [theme music] If there is one planet that
represents the majesty, mystery, and awe of the
universe, it is Saturn. It stirs emotion, even from
scientists who are stunned by its cosmic perfection. NEIL DEGRASSE TYSON: You've got
to hand it to Saturn for being the most beautiful
thing out there. It's been my favorite
planet since I first saw it through a telescope. NARRATOR: While it
looks sleepy and serene, the sixth planet from
the sun is anything but. Saturn is a dynamo whose
beauty is skin deep. ROB ROY BRITT: Saturn is
an absolutely frigid place. You wouldn't want to
step out on the surface. For one reason, you'd fall
because there is no surface. But secondly, you'd
freeze to death instantly. NARRATOR: Saturn is
a hunk of hydrogen and helium that races around
its axis, distorting its shape. LAURA DANLY: When you watch
a professional toss a pizza, as it spins around,
it flattens out, so it's the same kind of idea. Because it's
spinning so rapidly, it's actually sort of squashed,
sort of bulges in the middle. It's called an oblate spheroid. NARRATOR: Even though
it's much more massive than our own planet, you'd
actually weigh slightly less on Saturn than you do on Earth. A 150 pound human would weigh
only 137 pounds on Saturn. That's because Saturn
has such a low density, the only planet in the solar
system less dense than water. JAY PASACHOFF: Saturn is so
bloated, the gases take up so much space compared to the
total amount of mass in Saturn, that its density
is less than one. So if we can get somehow
some really big ocean and put Saturn in
it, it would float. NARRATOR: Saturn is the
second largest planet in our solar system. It is a gas giant, a mass
of hydrogen and helium 750 times the size of Earth. A day on the planet
is 10.6 hours long, and it takes 29.5
Earth-years to orbit the sun. It has 48 named moons. Saturn has been around for
4 and 1/2 billion years. It formed by
excreting carbon dust, particle by particle, into
a rocky core several times the size of Earth. Then it was able
to attract gases, like hydrogen and helium,
which collapsed under gravity. JAY PASACHOFF: As
things start collapsing, this cloud began to compress. It began rotating more rapidly. But along its axis, from
let's say top to bottom, it wasn't rotating, so
it was free to collapse under the force of gravity. NARRATOR: It's called
the conservation of angular momentum,
a principle on display at your local ice rink. JAY PASACHOFF: If you push
your arms out if you're an ice skater, you'll go more slowly. If you pull your
arms in, then you'll be more concentrated towards
the axis of rotation, and you'll have to spin faster. And that's just what happens
for a planet as it condenses. NARRATOR: A spinning Saturn
came out of this collapsed disk. The feature that has made
Saturn the most iconic planet in our solar system is her
majestic, shimmering rings. They are incredibly big,
173,000 miles in diameter, wider than 21
Earths side by side. So it would take you two days
in a really fast rocket ship to get from one side of
the rings to the other. They're huge. NARRATOR: However, these huge
rings also are unbelievably thin, measuring about 65 feet. When viewed from the side,
they virtually disappear. They are no thicker
than about one, maybe two stories in
a modern-day building. They're paper thin
in comparison. NARRATOR: The rings may look
like perfect, solid disks. However, they are actually
made up of billions of pieces of space debris. But what exactly are they? CAROLYN PORCO: They are
countless icy bodies that range in size from
objects as big as houses all the way down to the finest,
powdery snow you might ski on in Utah. And they're made of water ice. LAURA DANLY: They're particles
that have been pulverized, so they've smashed
into each other. They've broken up into
many, many little particles. KEVIN BAINES: If you were
to be inside those rings, it would be like a beehive. They're all over the place,
like bees in a swarm. It's a hostile place. You do not want to try to put a
spacecraft through those rings. NARRATOR: And these
particles spin very fast. And they're screaming around
the planet at 20,000 to 40,000 miles per hour. NARRATOR: The inner rings spin
faster than the outer rings, and there's a reason for that. Kepler's laws
say that if you're going to orbit in a circle
around a central body, if you're close up,
you move really fast, and you're far away,
you move really slow. NARRATOR: If a particle
the size of a grain of sand moving at hypersonic speed
were to strike a spacecraft, it would be like a shotgun
blast at point-blank range. And now get outside the
rings, things are much quieter. If you want to take a
country drive around Saturn, go this way instead of
following the rings. NARRATOR: Why the
rings are there is one of the planets
great mysteries. The rings might have once
been some of Saturn's moons that got too close and
smashed into each other. The fractured pieces were
held by the planet's gravity to become its rings. According to another theory,
something big and fast might have crashed into
one of Saturn's many moons. The broken shards were
sucked in by gravity and fell into orbit,
forming the rings. Although scientists disagree as
to how the rings were formed, they do agree as to
who first studied them. In 1610, the Florentine
astronomer Galileo Galilei first noted the rings of Saturn. ROB ROY BRITT: He saw these
little things sticking out on the side of the planet. He had no idea what they were. So like any good astronomer,
Galileo kept a journal, and he wanted to write into
his journal what he had seen. But he didn't have
a word for it. So in his journal, writing with
the words, he drew in a drawing in place of a noun. And this is what he drew. Here's Saturn, and
here's these two things. Unfortunately, Galileo never
really figured out what it was. We had to wait for a later
astronomer to do that. NARRATOR: 45 years later, a
Dutch physicist, Christian Huygens, had an answer. He knew that there
wasn't just one ring, but several giant rings. Today, there are seven
known ring regions. CAROLYN PORCO: There's the A
ring, the B ring, and the C ring. So those are the
three main rings. There is a ring interior to
the C ring called the D ring. And once we got
there with Voyager, it showed us the F
ring in all its glory. And then there are some diffuse
rings outside, the E and the G ring. NARRATOR: Each of these rings
has a different personality. The A ring is
almost transparent, which is why light
easily passes through it. The B ring is dense,
chock full of material. The C ring is even more
transparent than the A, while the D ring
is barely there. There's a lot of neat
things in those things, so you can't think of them
as a homogeneous body. You've got to think of each
particle inside those rings and what each one's doing. NARRATOR: These
distinct qualities are what we see as colors,
shapes, and shadows, the wonder that
is Saturn's rings. The reason we can see them
at all is due to the sun. Just as our moon glows
with reflected sunlight, so do Saturn's rings. It is a phenomenon
called ring shine. Just imagine yourself on
the night side of Saturn looking up and having the
rings just completely covering the sky. It's much brighter than if
the Earth on a full moon. ROB ROY BRITT: They shimmer,
and they're brilliant, and they're bright. And that's because
they're mostly made up of ice particles which
reflect a lot of sunlight. NARRATOR: However,
there is evidence that the glowing marvels
of our solar system won't be around forever. Some scientists are asking
just when will they disappear? For all scientists know
about Saturn's rings, they remain a huge mystery. When they appeared is
a point of much debate. Scientists used to believe
that the rings were formed at the same time as Saturn,
4 and 1/2 billion years ago. But because we don't
understand what holds the rings together, and our best guess
as to how long the rings could stay together is only a
few hundred million years, there's something wrong
with this picture. CAROLYN PORCO: There
are reasons to believe they are no older than a few
hundred million years old. Those reasons lie in trying to
estimate how much erosion is taking place on the rings
because of the hailstorm of micro meteorites, small,
tiny particles that come in at a tremendous speed and
chip away at the rings, and therefore erode them. NARRATOR: Neptune, Uranus,
and Jupiter also have rings, but theirs are sparse and dim. Saturn's are bright and
full, leading scientists to suggest that they
haven't been exposed to erosion for long, and
therefore are relatively new. But does this gradual erosion
mean that Saturn will lose its most magnificent feature? The idea is that over
long periods of time, the material can just get so
small that it can be charged, end up acquiring a charge
in Saturn's magnetosphere, and then it can just get
zipped away, taken away by the magnetic field. Or it just spirals
into Saturn itself. That is a scenario for
the death of the rings is that they finally
get eroded away. NARRATOR: In order for Saturn
to continuously have rings, they need to be refilled. At the moment, Saturn has a
tremendously large ring system, but the actual
material in the rings does have to be replenished. NARRATOR: Strangely,
another kind of assault might be necessary
to preserve them. They have to get renewed
by an errant comet coming in and crashing, adding to the
mass that's going around there. And that kind of question
is still being debated. NARRATOR: The debate continues
when theorizing as to when the rings will vanish. Hundreds of millions of
years probably, maybe billions of years.
We don't know. That's a matter of
debate right now, whether the rings are
young and are going to die an early
death, or they're old and they're going to remain
with us for a very, very, very long time. NARRATOR: Of Saturn's
48 named moons, there are small moons, called
shepherds for good reason. They have gravitational
pulls that help keep the rings intact
by herding the particles. Saturn's experts are interested
in the complicated choreography between the planet's
moons and its rings. The contorted F ring is
especially intriguing. And then there's the
two shepherd satellites on either side,
Prometheus and Pandora. And they are having
gravitational effects on this ring. It's being tugged in a
variety of directions, so it looks wild and
misbehaved, if you will. And it's a dynamicist's
playground. I mean, we're very,
very interested in watching what
happens to the F ring because it tells us how
moons interact with rings. NARRATOR: Saturn mesmerized
civilizations as early as 700 BCE when the Assyrians
took note of it sparkling in the distant sky. Hundreds of years later, the
Greeks gave it a name, Cronos, after the god of harvest,
possibly due to its position in the sky during
harvest season. The Roman's god of
agriculture was Saturnus, which is why we call it Saturn. They also named
a day of the week after it, what we
now call Saturday. However, had the Romans actually
seen the planet close up, they might have named it
for the god of weather. Saturn is a wild,
ever-changing place, but unlike on Earth where things
change on a daily and even an hourly basis, the storms
on Saturn can last for days, and weeks, and months, and
things change on a large scale very slowly over time. NARRATOR: The discovery of
this violent activity on Saturn came as a surprise to experts. For centuries, their
view of the planet had been obscured by
an ammonia gas haze. New satellite data is
changing everything. And we see now that
Saturn is a dynamic place. It's been revealed now as
being probably more dynamic in a lot of ways than Jupiter. There's the number of storms we
see, the motions that they do. NARRATOR: Incredibly,
winds blow at speeds of 1,000 miles per hour. We measure the winds
literally by watching the different little cells of
the atmosphere move in imaging. So you need sequential images to
see how much things have moved. There are no mountains
on the surface of Saturn. It's cloud features
that we look at to see how quickly they
evolve, and change, and move to measure the winds. NARRATOR: Recent exploration
has shown other phenomena that aren't yet understood. We can see features, clouds,
eddies, big plumes of material like we see on Jupiter. And we see these ovals
storms, lots of them. In fact, there's one latitude
in the southern hemisphere where lots of storms zip
around this band, and we've watched
them be created. We've seen them die. They die by merging. NARRATOR: Scientists nicknamed
this area Storm Alley after a region in
America's Midwest that produces violent weather. It is believed there
is lightning there, though no one has seen it. ANDREW INGERSOLL: And there's
a technical reason for that. To see the lightning, you have
to get around on the night side because the lightning flashes
aren't all that bright, and so you need the darkness. But the night side of Saturn
is very bright because of all the ring light that shines down
on the night side of Saturn, and so it's very hard to sort
the lightning from just puffy, little clouds. NARRATOR: The hellish
weather on Saturn has one more
astounding surprise, and it's a true monster. One of the freakiest storms on
Saturn was this hurricane-like thing that they found
down at the south pole. Now, this storm is bigger
than the United States. NARRATOR: The Great
Red Spot on Jupiter is merely hurricane-like. That storm doesn't
have an eye wall. However, the south pole
storm has the characteristics of a terrestrial hurricane,
including an eye wall, making it the only such
storm on another planet. CAROLYN PORCO: It's
not clear that it is a hurricane in every sense,
like we have here on Earth. But so far, the
morphology of it looks very much like a hurricane. That was very exciting. Everyone got very
excited about that. It even surprised us. ROB ROY BRITT: And you can
see right down into the eye, just as you can with
a hurricane on Earth, and they can see farther
into Saturn's atmosphere than they've ever been
able to see before. So this thing is literally
a window into Saturn, and it's amazing to see
something so similar to Earth on Saturn and then
find out that we can actually do some science because of it. NARRATOR: The south pole storm
measures 5,000 miles across. That's 2/3 the
diameter of the Earth. If a hurricane that
huge were to form here, it would cover a distance
from New York City to Baghdad, annihilating all in its path. It's basically a
swirling vortex of air that is centered around a hole
right in the center with a wall eye around it. NARRATOR: What powers this
monster storm is still unknown. ANDREW INGERSOLL: And the
winds are stronger on Saturn than they are on Earth,
which is a puzzle in itself because Saturn gets so little
energy from either the sun or from its own inside. ROB ROY BRITT: It's centered
around the south pole of Saturn, rather than being
in the equatorial region like a hurricane
on Earth would be. NARRATOR: In early 2007,
modern imaging technology revealed something else
on Saturn that astounded scientists. We see it very intensely now. NARRATOR: It's something
big, something strange, and something never seen
in the universe before. Saturn, the solar system's most
bizarre, yet beautiful, planet has just gotten even
more mysterious. In 1979, the Voyager spacecraft
showed a perfect geometric form over the north pole. In October 2006,
the Cassini craft found that it is still there. KEVIN BAINES: It's
just bizarre, and it sits there kind of still. It doesn't move with the planet. The pole, there's a hexagonal
feature, a six-sided polygon that encircles the pole at
about 78 degrees north latitude. And it's sitting there
as a set feature. NARRATOR: The hexagon is similar
to Earth's polar vortex, which has winds blowing in a circular
fashion around the pole. Saturn's vortex can fit
four Earth's inside of it and extends 60 miles deep
into Saturn's clouds. KEVIN BAINES: And
what's more bizarre, Voyager saw little tiny
clouds going around it at about 100 meters
per second, which is about 200 miles an hour,
going around this racetrack. People thought, well, maybe
it's just a temporary thing. How could this stay there? It's been there now for at
least 20 years, and we're going, what is this? ROB ROY BRITT: If
you go there, you are going to enter
these thick clouds. And the deeper you
go, the more intense the pressure is going to get, to
a point when you just implode. You and your spacecraft
can't make it any farther. NARRATOR: For now,
visits to Saturn's orbit are reserved for
unmanned spacecraft. But surrounding the planet
are at least 48 moons. Venturing to one of
those is more feasible. What's interesting, now that
we're going to the planets, is that we're learning
that, in some ways, the moons are where
the action is. NARRATOR: We've already
been to one of them. Titan is the only moon
other than our own to have been explored. The event was
beyond significant. On January 14, 2005,
science fiction became fact. As part of the ongoing
Cassini mission to Saturn, the unmanned Huygens Probe
descended onto the surface of Saturn's biggest moon. Titan lives up to its name. It is the size of
the planet mercury. In fact, it is the
second largest moon in the solar system, 50%
bigger than our moon. It is seductive in many ways. For one, Titan looks
much like Earth. CAROLYN PORCO: That was
the thing that hit me over the head, just how
remarkably similar in process the surface of Titan looked. We have river channels that
feed into these lake beds. We have winds. And then in other
areas, we have dunes. The equator region of Titan,
at least on the one side where we've gotten
good radar imagery, has hundreds and hundreds
of miles of these dunes that are a hundred meters
high, several miles apart, and they just go on,
this vast sea of dunes. NARRATOR: There are possibly
deposits of solid hydrocarbons. BONNIE BURATTI: And
we didn't really know until that probe landed
whether it was going to hit liquid or some solid surface. It seemed to kind
of fall on what looks like kind of pudding. It doesn't seem to
be liquid or solid. It seems that Titan has
some goo on the surface. It's almost kind of
neither land nor sea, but something in between,
and that's very amazing. NARRATOR: Amazingly,
Titan, like Earth, has an extended
atmosphere, no other moon does in our solar system. MARGARET TOLBERT: The
atmosphere of titan is very, very thick,
very, very massive. It has a mass that's 10
times the mass of the Earth's atmosphere. And so we have a very,
very thick layer of gases. It's thicker than the
air as we know it. The particles in the
air are also very small. And so I would characterize
them more as a haze than as a fog or clouds. NARRATOR: The haze is 200
miles thick, resembling something else on earth. LAURA DANLY: From the outside,
it appears essentially opaque, like a big orange ball. But as the Huygens
Probe descended through the atmosphere,
it's transparent enough to be able to see the surface
features as it fell through. But it's not unlike a hazy
day here in Los Angeles. NARRATOR: It's not the color
of the atmosphere that most intrigues scientists,
it's the composition-- nitrogen and methane, the
same gases they believe made up much of Earth's
early atmosphere. The idea that Titan's
atmosphere mimics the atmosphere of early
Earth, four billion years ago, is something we're very, very
excited about and interested in, and it's one of the
things we're studying very hard in our laboratory. Let's see if we
get this aligned. What do we have? NARRATOR: At the
University of Colorado, Dr. Margaret Tolbert is
simulating Titan's atmosphere in her lab. Might it, too, have the
necessary ingredients for life? In this experiment,
we're trying to simulate the
chemistry that goes on high in Titan's atmosphere
where the haze is forming. And so what we have is
a reaction chamber here, and all that we have in there
is nitrogen and methane, so the two most important
components of Titan's atmosphere. And then we're just
going to flick on a lamp, and that lamp is going to
simulate the sunlight hitting Titan's atmosphere. NARRATOR: Incredibly,
Tolbert's research has shown that Titan's
atmosphere, when stimulated by sunlight, begins to
produce organic compounds. To scientists looking for
life beyond our planet, this could be big. As scientists scour the
galaxy for signs of life, there are some
exciting results from within our own solar system. Saturn's moon, Titan, seems to
have the necessary ingredients. Testing at the
University of Colorado has shown that when sunlight
interacts with Titan's nitrogen and methane-rich atmosphere,
organic compounds are created. MARGARET TOLBERT:
So these organics are floating down to
the surface of Titan, and you can see them
in the pictures. And who knows what
they're doing. Once they're there. They could be providing energy
to some new kind of life. NARRATOR: Further
research is needed to determine if there
really is life on Titan or if it might someday develop. Although its atmosphere
resembles early Earth, the environment is
vastly different. It's cold. It's 300 degrees
below zero Fahrenheit, and there's no liquid water. So that's a big difference
between early Earth and Titan. NARRATOR: The lakes
and riverbeds on titan were carved out of the
ground by something. There's no liquid
water on the moon, so what flows on this terrain? The hills on Earth are
made of silicate rocks, whereas the hills on Titan
are ice and methane ice. The river channels on titan
are formed by methane rain, as opposed to the Earth river
valleys formed by water. NARRATOR: Liquid methane, it
seems, rains down on Titan-- or did at one time. On Titan, it is so cold
that gas has liquefied, and there are coastlines and
rivers and all this terrain shaped by moving
rivers of methane. It's just completely intriguing. NARRATOR: Methane is
the principal component of natural gas,
butane, and propane-- all sources of fuel. ANDREW INGERSOLL: There's
a lot of hydrocarbons. It might be very light
hydrocarbons on Titan. And there is a lot of it. And it burns if you put
it in contact with oxygen, so there's a lot of
energy out there. NARRATOR: Enough on the
surface of this huge moon to supply all of Earth's
needs for a very long time. ROB ROY BRITT: Well, here's
this tremendous supply of natural gas on Titan. Boy, wouldn't it be great to
go out there, and tap into it, and bring it back? But I think that you would find
that it would cost you so much to go out and get the methane
and bring it back that you would never be able to
effectively power anything on Earth with it. NARRATOR: While Titan is
Saturn's largest moon, one of its smallest may
be even more exciting. It's a brilliant ball of ice
and rock called Enceladus. It's a tiny object. It's only about
300 miles in size. So that's what? About eighth the
size of our own moon. And we've never seen a body that
small that has activity on it. NARRATOR: This activity
was discovered in 2005 by Dr. Carolyn Porco and
her Cassini imaging team. One photo seemed to suggest
that jets were coming out of Enceladus. CAROLYN PORCO: It seemed
very likely to the members of my team that it's possible
that these jets are actually geysers. They're erupting from
pockets of liquid water not too far beneath the surface. JOHN SPENCER: The closest thing
we have on Earth to Enceladus is something like Old Faithful
Geyser here at Yellowstone National Park which is shooting
water vapor and water about 150 feet into the air. The geysers on Enceladus are
erupting water vapor hundreds of miles into the air because
of much lower gravity there and the fact there is no
atmosphere holding them in. NARRATOR: Many
geysers have since been discovered, all in
a region of Enceladus' southern hemisphere. They are coming out
of these fissures, these big cracks that go on for
about 135 kilometers, something like 80 miles of cracks. BONNIE BURATTI: We
call them tiger stripes because when we first saw
them they really looked like the stripes on a tiger. There are four areas that
seem to be ridges or kind of active geologic areas. And the plume seemed to be
coming out of these areas, and we've counted
about 20 or 21 plumes. NARRATOR: Southern
Enceladus is covered in cosmic old faithfuls. KEVIN BAINES: Who would've
thought that an ice ball about the size of Texas
would be alive with plumes and geysers? I mean, it's astounding. JOHN SPENCER: Enceladus
is heated in its interior by the tides of Saturn. The Earth's moon is pulling
on the Earth's oceans and distorting their shape and
producing the tides that we're familiar with here on Earth. But on Enceladus, the planet
Saturn is pulling on that moon, and as Enceladus goes
around in its orbit, that pull is changing. And the ice inside Enceladus
is creaking, and groaning, and rubbing against itself
and creating a lot of heat through friction. We think it's that frictional
heat that is producing the evaporation of the water
ice that is then escaping through these cracks and making
the geysers that we see there. NARRATOR: And there's more. Enceladus' eruptions have
clarified a theory of what powers one of Saturn's rings. We knew there might be
jets, something coming from the surface that was
injecting material into orbit around Saturn to
form the E ring. NARRATOR: The E ring is
furthest from the planet, about four 74,000 miles away. It happens to be just at the
same orbit, the same distance from Saturn as Enceladus. And so it really suggests
that it owes its origin to Enceladus. And the thickness of
the E ring sort of matches the thickness
of particles that were ejected from the
south pole of Enceladus. NARRATOR: If these geysers
disappear, so might the ring. Ultimately, the liquid
jets suggest that there is water on Enceladus-- and perhaps something else. So the search for water is
not that, oh, one day we'll be thirsty, so we'll
have something to drink. The search for water is
guided by our interest in the search for life. It's that simple. Follow the water. NARRATOR: Saturn's
moon Enceladus is one of the most exciting
and least understood places in our solar system. Enceladus is a
really strange place. The strangest thing that
got people's attention first is it's very, very bright. It's the whitest object
in the solar system. And we now realize that it is
covered in freshly fallen snow, which is the ice that's
fallen back from these geysers onto the surface. NARRATOR: And it's that ice
that has scientists excited. Possibilities
there are amazing. The search for water
in our solar system is ultimately a search for life. You look for water in the hopes
that maybe there will be life. NARRATOR: Because of
the presence of ice, some experts believe the
search for alien life should begin on Enceladus. KEVIN BAINES: That has a lot
of other molecules in it, a lot of other exotic things
which show us that there's aqueous chemistry
going on underground. So there's a lot of little
percolating kind of chemistry going on, and maybe you
could get biology maybe. And so maybe we should go look. CAROLYN PORCO: This is kind of
the holy grail of modern day planetary exploration, to go
and seek out those environments in the solar system where life
might possibly have gotten started, and we just
stumbled upon it. Is that exciting? Oh, of course it's exciting. It's the kind of thing
scientists live for. JOHN SPENCER: We know of the
composition of the gases that are coming out because
we've flown through them with the spacecraft, and we've
got the composition, including carbon, and nitrogen,
and all those goodies that you need to make life. And then we know there's
a source of energy from the frictional heat or
the tidal heat in the interior, and we can see the
heat on the surface. So all these elements
are there that might be sufficient to sustain
life if life could have got started there. So that makes Enceladus
a very exciting place. NARRATOR: But what kind of life? CAROLYN PORCO: We're
not talking sushi. We're not talking
lobsters and fish. We're talking microbes. I think that's about the
best that we can hope for on a moon like Enceladus. If we ever discover such
life in our solar system, it's going to be the
simplest possible. It's going to be bacterial,
something like it. NARRATOR: Even the
discovery of something small would be a huge event. It would change everything
that we think and know about our solar system, the
universe, and ourselves. NARRATOR: Much of what is known
about Saturn and its moons has come from the
Cassini satellite that was inserted into the
planet's orbit in 2004. It is currently touring its
rings, moons, and the planet itself. By 2008, Cassini will have made
70 trips around the gas giant. Putting an orbiter
around a planet and being able to hang out there
and monitor the system and all the different elements of
the system for a long period of time, I mean, that's the
best way to study these bodies. NARRATOR: Scientists on
a daily basis process the information sent back
from these close encounters. ANDREW INGERSOLL: In
addition to the camera, there is a radar that
can send its radio waves through the clouds,
get an echo off the surface, and make an image
of the surface. And then there's spectrometers
to measure the composition and other infrared devices
to measure temperature. So it's a very
comprehensive spacecraft. As you see better,
you learn more. I think it may have been Yogi
Berra who said you can see a lot just by looking. NARRATOR: Relating
this information to processes on Earth could
help explain mysteries of our own planet. Saturn is really very
different from the Earth. Its diameter is
eight or nine times greater than that of the Earth. Its atmosphere is
made of hydrogen, completely different
from our own atmosphere. But the same
physics is going on, the same forces are controlling
the weather on Saturn as are controlling
the weather on Earth. LAURA DANLY: It is
part of our history. It's the solar system,
so understanding how our solar system
formed is really understanding how I got here. And understanding the nature
of the other planets that are in the solar system, I
mean, they're like my neighbors. NARRATOR: Cassini's new
imaging technologies are giving us never before
seen views and information by the day. Cassini's close
encounters with Saturn will bring us nearer to
unlocking its secrets. It's quite complex, and
it'll take us a long time to figure it all out. I don't think we ever
will figure all of it out. But it's just the beauty of
being able to be in orbit and monitor a rich planetary
system like Saturn's. NEIL DEGRASSE TYSON: The Earth
has a context in the rest of the universe,
and you want to know where we fit in the universe? You don't get the answer to that
just studying the Earth itself. NARRATOR: For as
much as we discover about the lord of the rings,
it will always inspire us.
