But what it there really is something here?
Hard to imagine, though. Up close, this is a dead planet
The activity that makes the Earth livable shut down millions of years ago here Red and dead Mars is a giant fossil. Wait. Something is alive A dust devil, a big one
Bigger than the biggest twisters back home. There's wind here
And where there's wind, there's air Could that air sustain extraterrestrial life? It's too thin tor us to breathe. And there's no ozone layer
Nothing to protect us against the Sun's ultraviolet rays. There is water...
...But frigid temperatures keep it in a constant deep freeze It's hard to believe anything could live here
Back on Earth, there are creatures that survive in extreme cold, heat... ...even in the deepest ocean trenches It's as though life is a virus. It adapts, spreads
Maybe that's what we're doing right now... ...carrying the virus of life across the universe.
Even in the most extreme conditions life usually finds a way. But on a dead planet?
With no way to replenish its soil, no heat to melt its frozen water? All this dust, it's hard to see where we're going
Olympus Mons, named after the home of the Greek gods A vast ancient volcano.
Three times higher than Everest. There's no sign of activity.
Since its discovery in the 1970s, it's been declared extinct Hang on.
These look like lava flows.
But any sign of lava should be long gone. obliterated by meteorite craters Unless, this monster isn't dead, just sleeping
There could be magma flowing beneath the crust right now... ...building up, waiting to be unleashed
Volcanic activity could be melting frozen water in the soil...
...pumping gases into the atmosphere, recycling minerals and nutrients Creating all the conditions needed for life
This makes the Grand canyon look like a crack in the sidewalk Endless desolation...
...so vast it would stretch all the way across North America.
But here, signs of activity, erosion, and what looks like dried up river beds Maybe volcanic activity melted ice in the soil... ...sending water gushing through this canyon.
Underground volcanoes could still be melting ice, creating water And where there's water, there could be life
The hunt for life is spearheaded by this humble fellow... ...the NASA rover, Opportunity.
It's finding evidence that these barren plains...
...were once ancient lakes or oceans that could have harbored life Look at those gullies.
Probes orbiting Mars keep spotting new ones. More proof that Mars is alive and kicking
...that water is flowing beneath its surface right now Water that could be sustaining Martian life Now, all we have to do is find it
Maybe we've already found what we're looking for on Earth Some think that life started here and then migrated to Earth An asteroid impact could've blasted fragments of Mars... ...complete with tiny microbes out into space...
...and onto the young Earth where they sowed the seeds of life No wonder we find Mars fascinating, this could be our ancestral home It could be we are all Martians
The Mars we thought we knew is gone... ...replaced by this new, active, changing planet. And if we don't know Mars, our next door neighbor... ...how can we even imagine what surprises lie ahead Our compass points across the cosmos... ...back in time 14 billion years... ...to the moment of creation. This is getting scary.
It's like being inside a giant video game But these are all too real.
Asteroids, some of them hundreds of miles wide This one must be about 20 miles long. And there, perched on it, a space probe. Can't have been easy...
...parking on an asteroid traveling at 50,000 miles an hour. It's a lot of effort just to investigate some rubble. Rubble that regularly collides...
...breaks up and rains down on Earth as meteorites. Our ancestors saw shooting stars as magical omens. And they were right
Rubble like this came together to make the planets... ...including our own
Pretty magical.
By dating the meteorites found on Earth
...we can tell the planets were born 4.6 billion years ago. These are the birth certificates of our solar system. For some reason, these rocks didn't form into a planet Something must have stopped them Something powerful. Jupiter. What a monster
At least a thousand time bigger than Earth... ...so vast you could fit all the other planets inside it Something this massive dominates its neighbors Its gravity is pulling the asteroids apart And it's breathtaking But this beauty is a beast. It's almost all gas.
Land here and we'd sink straight through its layers into oblivion. And Jupiter's good looks? The product of ferocious violence It's spinning at an incredible rate
...whipping up winds to hundreds of miles an hour... ...contorting the clouds into stripes eddies, whirlpools... ...and this, the legendary Great Red Spot
The biggest, most violent storm in the solar system.
At least three times the size of Earth, it's been raging for over 300 years All these churning clouds must have sparked an electrical storm Just one bolt is 10,000 times more intense than any at home. Looks like the safest place to see Jupiter is from a distance Up there at the poles...
...those dancing lights, they're like the auroras back home. But the Geiger counter is going wild
Even these are deadly, generated by lethal radiation Out here, nothing is what it seems. The universe is full of terrors, traps.
Maybe this is a safe haven, the multi-colored moon, Io Wrong Very wrong.
Those brilliant colors are molten rock, volcanoes spewing lava. Our journey across the universe is turning into a struggle for survival We've got to hope that if we outlast the dangers... ...we'll be rewarded by wonders beyond imagination Four hundred million miles from Earth...
...flying a commercial airliner here would take nearly a century What a weird looking place...
...and yet, strangely familiar
A bit like the Arctic, with all that ice, all those ridges and cracks It's Jupiter's moon, Europa.
And maybe, like the Arctic, this ice is floating on water, liquid water But we're half a billion miles from the Sun. Surely, Europa is frozen solid
Unless, Jupiter's gravity is creating friction deep inside...
...heating the ice into water, allowing life to develop in the water... ...beneath its frozen crust. We might be feet away from aliens
From a whole ecosystem of microbes, crustaceans, maybe even squid The only thing between us and the possibility of alien life... ...this layer of ice.
But until we send a spacecraft to drill here... ...Europa's secrets will remain beyond reach It's captivated our imaginations, haunted our dreams And here it is, spinning before our eyes Saturn.
Named for the Roman god...
...who reigned over an golden age of peace and harmony This planet's a giant ball of gas, so light it would float on water Its spectacular rings would stretch almost from Earth to the Moon. There's the Cassini orbiter
It's picking up ghostly radio emissions
Probably generated by auroras around Saturn's poles This is the real music of the spheres.
Cassini's telling us where these rings came from.
They're the remnants of a moon shattered by Saturn's gravitational pull Incomparable beauty from total destruction Billions of shards of ice
Some as small as ice cubes, others the size of houses. They collide, break apart, reassemble It's like a snapshot of our early solar system... ...as dust and gas orbited the newly born Sun
...and gravity worked this magic pulling the lumps together... ...until from space trash like this, our home emerged We could stay here forever
But there's so much further to go, so much more to see. Like this moon wrapped in thick clouds, Titan. There's an atmosphere down here There's wind, rain ,even seasons Rivers, lakes and oceans
It looks so familiar, so similar to Earth. But that's not water, it's liquid natural gas
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