Hundreds of times more natural gas than all the Earth's oil and gas reserves Maybe, one day, we'll use this energy to fuel a colony. Assuming there isn't life here already The Huygens space probe is here to find out It's telling us there's organic material in the soil. But it's so cold, minus 300 degrees There's no way life could develop Unless Titan warms up.
The Sun is supposed to get hotter
When it does maybe life will spring up here... ...just like it did on Earth
And as the Earth gets too hot for us, maybe we'll move to Titan. One day, we might call this distant land home Home.
We're at least 700 million miles away now. After this we lose visual contact with Earth. We're standing on a cliff
Looking out over a great chasm that stretches to the beginning of time. Do we have the courage to jump? We're in the solar system's outer reaches. Unseen from Earth, unknown for most of history It's like diving into the depths of the ocean
Those rings make it look like Uranus has been tilted off its axis ...toppled over by a stray planet It's eerie out here.
Already beginning to feel small, lonely
Maybe this is how we'll feel at the edge of the universe But we've barely left the shore
If the solar system was one mile wide, so far we've traveled about 3 inches Out of the deep, another strange beast... ...the god of the sea, Neptune This world is covered in methane gas And a storm as big as Earth...
...whipped up by savage thousand mile-an-hour winds Back home, it's the Sun that drives the wind... ...But Neptune's far away.
Something else must be creating these ferocious winds But what?
We know very little about our own solar system. After all those balls of gas a solid moon ...Triton.
Solid but not stable Just look at those geysers...
...cosmic smokestacks pumping out strange soot.
And this moon is revolving around Neptune ...in the opposite direction of the planet's spin. A cosmic battle of wills...
...that this angry moon is destined to lose Neptune's massive gravity is pulling on Triton. Slowing it down, reeling it in
One day, it will be ripped apart by Neptune And that's it
No more moons, no more planets in our solar system. It's getting colder, we're getting further from the Sun... ...slipping from the grip of its gravitational tentacles. But this isn't a void
It's teeming with frozen rocks. Like Pluto.
Until recently, we thought Pluto was alone. Beyond it, nothing We were wrong More frozen worlds
Discoveries so new nobody can agree what to call them Plutinos, ice dwarves, cubewanos
Our solar system is far more chaotic and strange than we had imagined Now we're 8 billion miles from home.
The most distant thing ever seen that orbits the Sun... ...another small, icy world, Sedna, discovered in 2003 Its orbit takes 10,000 years to complete. Hang on, there's something else out here.
Ten billion miles from home the space probe, Voyager 1. This bundle of aluminum and antennae... ...gave us close up views of the giant planets... ...and discovered many of their strange moons.
It's traveling 20 times faster than a bullet, sending messages home That gold plaque...
...its a kind of intergalactic message in a bottle. A greeting record in different languages
And a map showing how to find our home solar system The great physicist, Stephen Hawking...
...thinks it was a mistake to roll out the welcome mat. After all, if you're in the jungle, is it wise to call out? These comets look like the ones we saw earlier.
There's a theory that the raw materials for life began out here... ...on a rock like this until something dislodged it... ...sending it hurting towards the Earth
And seeding all this ice, maybe comets carried water to Earth too The water in the oceans, in your body...
...all from this distant celestial ice machine.
We're 5 million, million, that's 5 trillion miles from home. But this is still only a baby step. Ahead, trillions of miles, billions of stars.
Time to stop looking back and start looking ahead... ...to step out into the big, wide universe Interstellar space.
Billions of stars like our own Sun...
...many with planets, many of those with moons. It's hard to know which way to go There are infinite possibilities.
We're going to need a serious burst of acceleration. Twenty-five trillion miles from home. A 150,000-year ride in the space shuttle.
And we're only just reached the first solar system beyond ...Alpha Centauri Not one but three stars.
Spinning around each other locked in a celestial standoff Each star's gravity attracting the other... ...their blazing orbital speed keeping them apart. Get between them and we'd be vaporized... ...trillions of miles from home.
So far that miles are becoming meaningless. Out here, we measure in light years. Light travels 6 trillion miles a year... ...so we are overfour light-years from home. Distances so vast they're mind-boggling Who knows what strange forces lie ahead ...what we'll discover when-- If we reach the edge of the universe
Ten light years from Earth, the star Epsilon Eridani Spectacular rings of dust and ice
And somewhere in there, planets forming out of debris... ...being born before our eyes. Asteroids and comets everywhere
We could almost be looking at our own solar system... ...billions of years ago.
With comets delivering the building blocks of life... ...to these young planets.
At the center of all the action, a star smaller than our sun... ...still in its infancy.
Any life in this solar system would be primitive at best There must be more mature solar systems out here...
...But finding them is like looking for a needle in a cosmic haystack
Twenty light years from Earth. Star Gliese 581
It's about the same age as our sun.
This planet is just the right distance from its sun
Any closer and water would boil away, any further and it would freeze Ideal conditions for life to emerge
And if a comet has struck, delivering water and organic materials... ...then life, complex beings like us, even civilizations like our own... ...could be down there right now
They could be tuning into our TV signals... ...watching shows from 20 years ago. But until we devise a way of communicating... ...over these vast distances, all we can do is speculate Us and them, living parallel lives... ...unaware of each other's existence. Unless life has come and gone That's the problem with comets. They're creators and destroyers... ...as the dinosaurs the hard way
This is the needle in the cosmic haystack...
...the closest we've come to a habitable solar system like our own... ...but it's a chance encounter. There could be hundreds...
...millions more solar systems like this out there or none at all. Some of the atmosphere on this planet, Bellerophon... ...is being boiled away by its nearby star. From Earth, we can't see planets this far out.
They're obscured by the brilliance of their neighboring stars. But the planets have a minute gravitational pull on those stars. Measure these tiny movements and we can prove they exit That's how we tracked down Bellerophon in the 1990's... ...and hundreds of other distant planets Sixty-five light years from Earth...
...turn on your TV here and you'd pick up Hitler's Berlin Olympics The twin stars of Algol.
Known to the ancients as the demon star
From Earth, it appears to blink as one star passes across the other. Up close, it's even stranger.
One star is being sucked towards the other Almost 100 light years from home...
...faint whispers from one of the first ever radio broadcasts From here on out, it's as if the Earth never existed Feels like a life time since we stood on that beach... ...looking up at the sky, wondering where and how we fit in
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