主机维修《旅行到宇宙边缘》英文解说

2021年1月2日发(作者：邓家栋)
Our world. warm, comfortable, familiar...
...But when we look up, we wonder:
Do we occupy a special place in the cosmos?
Or are we merely a celestial footnote
Is the universe welcoming or hostile?
We could stand here forever, wondering
Or we could leave home on the ultimate adventure
To discover wonders
Confront horrors
Beautiful new worlds
Malevolent dark forces
The Beginning of time.
The moment of creation.
Would we have the courage to see it through?
Or would we run for home?
There's only one way to find out
Our journey through time and space begins with a single step.
At the edge of space, only 60 miles up...
...just an hour's drive from home
Down there, life continues.
The traffic is awful, stocks go on trading
...and Star Trek is still showing
When we return home, if we return home...
...will it be the same?
Will we be the same?
We have to leave all this behind
To dip out toes into the vast dark ocean
On to the Moon.
Dozens of astronauts have come this way before us
Twelve walked on the moon itself
Just a quarter of a million miles from home.
Three days by spacecraft
Barren.
Desolate.
It's like a deserted battlefield
But oddly familiar.
So close, we've barely left home
Neil Armstrong's first footprints.
Looks like they were made yesterday
There's no air to change them.
They could survive for millions of years
Maybe longer than us.
Our time is limited
We need to take our own giant leap
One million miles, 5 million, 20 million miles.
We're far beyond where any human has ever ventured
Out of the darkness, a friendly face
The goddess of love, Venus.
The morning star.
The evening star.
She can welcome the new day in the east...
...say good night in the west
A sister to our planet...
...she's about the same size and gravity as Earth.
We should be safe here
But the Venus Express space probe is setting off alarms
It's telling us, these dazzling clouds, they're made of deadly sulfuric acid
The atmosphere is choking with carbon dioxide
Never expected this Venus is one angry goddess.
The air is noxious, the pressure unbearable.
And it's hot, approaching 900 degrees
Stick around and we'd be corroded suffocated, crushed and baked
Nothing can survive here.
Not even this Soviet robotic probe.
Its heavy armor's been trashed by the extreme atmosphere.
So lovely from Earth, up close, this goddess is hideous
She's the sister from hell.
Pockmarked by thousands of volcanoes
All that carbon dioxide is trapping the Sun's heat.
Venus is burning up.
It's global warming gone wild
Before it took hold, maybe Venus was beautiful, calm...
...more like her sister planet, Earth.
So this could be Earth's future
Where are the twinkling stars?
The beautiful spheres gliding through space?
Maybe we shouldn't be out here, maybe we should turn back
But there's something about the Sun, something hypnotic, like the Medusa
Too terrible to look at, too powerful to resist
Luring us onward on, like a moth to a flame.
Wait ,there's something else, obscured by the sun
It must be Mercury.
Get too close to the sun, this is what happens.
Temperatures swing wildly here
At night, it's minus 275 degrees
...come midday, it's 800 plus.
Burnt then frozen.
The MESSENGER space probe is telling us something strange.
For its size, Mercury has a powerful gravitational pull.
It's a huge ball of iron, covered with a thin veneer of rock
The core of what was once a much larger planet.
So where's the rest of it?
Maybe a stray planet slammed into Mercury
...blasting away its outer layers in a deadly game of cosmic pinball
Whole worlds on the loose careening wildly across the cosmos...
...destroying anything in their path
And we're in the middle of it
Vulnerable, exposed, small
Everything is telling us to turn back.
But who could defy this?
The Sun in all its mesmerizing splendor
Our light, our lives...
...everything we do is controlled by the Sun
Depends on it
It's the Greek god Helios driving his chariot across the sky
The Egyptian god Ra reborn every day
The summer solstice sun rising at Stonehenge.
For millions of years...
...this was as close as it got to staring into the face of God
It's so far away...
...it is burned out, we wouldn't know about it for eight minutes
It's so Big, you could fit one million Earths inside it
But who needs number? we've got the real thing
We see it every day, a familiar face in our sky
Now, up close, it's unrecognizable.
A turbulent sea of incandescent gas
The thermometer pushes 10,000 degrees
can't imagine how hot the core is ,could be tens of millions of degrees
Hot enough to transform millions of tons of matter
...into energy every second
More than all the energy ever made by mankind
Dwarfing the power of all the nuclear weapons on Earth.
Back home, we use this energy for light and heat
But up close, there's nothing comforting about the Sun.
Its electrical and magnetic forces erupt in giant molten gas loops.
Some are larger than a dozen Earths
More powerful than 10 million volcanoes.
And when they burst through they expose cooler layers below...
...making sunspots.
A fraction cooler than their surrounding, sunspots look black...
...But they're hotter than anything on Earth.
And massive up to 20 times the size of Earth.
But one day, all this will stop
The Sun's fuel will be spent.
And when it dies, the Earth will follow
This god creates life, destroys it...
...and demands we keep out distance
This comet strayed too close
The Sun's heat is boiling it away...
...creating a tail that stretches for millions of miles.
It's freezing in here.
There's no doubt where this comet's from, the icy wastes of deep space
But all this steam and geysers and dust...
...it's the Sun again, melting the comet's frozen heart.
Strange.
A kind of vast, dirty snowball, covered in grimy tar
Tiny grains of what looks like organic material...
...preserved on ice, since who knows when...
...maybe even the beginning of the solar system.
Say a comet like this crashed into the young Earth billions of years ago.
Maybe it delivered organic material and water
...the raw ingredients of life
It may even have sown the seeds of life on Earth...
...that evolved into you and me
But say it crashed into the Earth now
Think of the dinosaurs, wiped out by a comet or asteroid strike
It's only a question of time.
Eventually, one day, we'll go the way of the dinosaurs
If life on Earth was wiped out, we'd be stuck out here...
...homeless, adrift in a hostile universe
We'd need to find another home
Among the millions, billions of planets...
...there must be one that's not too hot, not too cold, with air, sunlight, water...
...where, like Goldilocks, we could comfortably live
The red planet
Unmistakably Mars.
For centuries, we've looked to Mars for company...
...for signs of life
Could there be extraterrestrial life here?
Are we ready to rewrite the history books, to tear up the science books...
...to turn our world upside down?
What happens next could change everything
Mars is the planet that most captures our imagination.
Think of B-movies, sci-fi comics, what follows?
Martians?
It's all just fiction, right?
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
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
We've learned one thing for sure
The universe is too bizarre, too startling...
...for us to guess what lies ahead
Deep inside our galaxy, the Milky Way
Pinpricks of light that have inspired a thousand and one tales
The Seven Sisters, the daughters of the ancient Greek god, Atlas
...transformed into star to comfort their father...
...as he held the heavens on his shoulders
And this giant, Betelgeuse
The brightest, biggest star we've seen so far.
Six hundred times wider than our sun
But this, it's not a star...
...not a planet, not like anything we've seen.
A ghostly specter, more than 1,300 light years from Earth...
...Orion's dark cloud
Dust and gas shrouding us
There, deep inside, a light, pulling the dust and gas towards it...
...heating up, merging into a ball of burning hot gas.
Like a star, like our sun in miniature.
Inside, it's millions of degrees
So hot, it's beginning to trigger nuclear reactions...
...the kind that keep our sun shining...
...making energy, radiation, light
A star is being born.
Orion's dark cloud is a vast star factory
We're witnessing the birth of the future universe.
We've come to expect destruction...
...but this is one of the universe's greatest acts of creation.
Star birth.
This doesn't look right
Jets of gas exploding out with tremendous force...
...blasting dust and gas out for millions of miles.
It's unbelievably violent and creative
Nebula...
...vast glowing clouds of gas hanging in space.
With no wind out here, they'll take thousands of years to disperse
They seem to be forming a vast stellar sculpture.
Nature is more than a scientist, an engineer...
...it's an artist on the grandest of scales
And this is a masterpiece
Stars are born, grow up, and then, then what?
Do they die?
Do they slip quietly into the night or go out with a bang?
Somewhere between here and the edge of the universe lies the answer.
Luminous clouds, suspended in space...
...encircling what was once a star like our own sun.
All that's left of it are these brightly colored gases...
...elements formed by nuclear reactions deep inside...
...released into space on its death
Green and violet, hydrogen and helium...
...the raw materials of the universe.
Red and blue, nitrogen and oxygen...
...the building blocks of life on Earth
For us to live, stars like this had to die
Every atom in our body was produced by nuclear fusion...
...in stars that died long before the Earth was even born.
We are all the stuff of stars
Our family tree begins here
At its heart, the ghost of a star...
...a white swarf
White, hot, small...
...but unbelievably dense
In the star's dying moments, its atoms fused and squeezed together
...making it so dense that just a teaspoon of this white dwarf would weigh 1 ton
It's a chilling premonition of our sun's fate.
Six billion years from now, it will become a white dwarf
Its death will herald the end of life on earth
Makes you wonder how many other world have come and gone...
...celestial stories left untold, lost forever.
But the greatest story of them all is still to be told
We must go back through time to the very first chapter...
...to learn how the universe began.
The scattered remains of dead star...
...the Crab Nebula
Six thousand light years from home, deep inside a stellar graveyard
We've learnt so much
...seen things we'd never have believed possible
Now, sights like this, wonders once beyond imagination...
...we take in our stride
We're ready to face whatever lies ahead
Determined to reach the edge of the universe
This is the calm after the storm, after an massive explosion...
...a supernova that turned a star into dust and gas
The eye of the storm.
A spinning pulsating star, a pulsar.
The gravity has squeezed the giant star's core down to this
It's just 12 miles across, unimaginably dense
One pinhead of this would weigh hundreds...
...maybe millions of tons.
And as it shrank , like a figure skater spinning on the spot...
...arms outstretched , then pulling them in...
...it began to spin faster.
Two beams of light, energy, radiation, spinning 30 times a second
Powering the huge cloud of dust and gas
There's so much radiation here, more even than on the Sun.
That was easily the deadliest thing we've encountered so far
Once, it would have terrified us
But now we realize that without the dangers...
...there'd be no wonders
Without the nightmares, there'd be no dreams
Getting a strange sensation
A feeling as though there's something bad out here...
...a malevolent presence.
The one thing we didn't want to encounter
Impossibly black, blotting out the stars behind it
...the remains of a giant star...
...a black hole.
Far denser than a pulsar...
...and impossible to resist
Its gravity is so intense, not even light can escape.
This asteroid, it's a lump of solid rock...
...but it's actually stretching, being dragged towards the gaping hole
Inside, there's no matter as we know it.
No time, no space, all the rules of physics collapse.
The asteroid is gone
Nobody really know where
This is the edge of human understanding
There could be millions of black hole creeping around our galaxy...
...more perhaps than all the stars in the sky...
...But we wouldn't see them until it was too late.
Like this star, spiraling...
...disappearing, down an invisible sinkhole
Who's to say we don't live inside a vast black hole...
...that the whole universe isn't inside one right now...
...inside another universe?
Think about it for too long and your mind reels
Sometimes it feels like the more we see, the less we know.
And we're still in our own galaxy, the Milky Way..
...the vastness of the universe beyond still lies ahead
The wonders, the dangers, the secrets, they're out there...
...waiting to be discovered
Seven thousand light years from home
It's as though we're in a forest thick with trees.
Each so beautiful, so fascinating, it's impossible to look beyond
...to see the bigger picture.
We have to find a way through...
...to reach the clearing at the galaxy's edge
But faced with sights like this, its hard to leave
A colossal glowing cloud topped by these great towers of dust
...the Pillars of Creation
Like a gateway into the unknown.
A star factory packed with embryonic star systems...
...each larger than our solar system.
we have to resist its siren song, tear ourselves away...
...to carry on towards the edge of the galaxy
Dazzled by the Milk Way's beauty, we've been blinded to its terrors
...and strayed into a cosmic minefield
Like an explosion in slow motion.
A massive star, millions of times brighter than our sun.
It's going into meltdown
The fuel that sustains it is running out...
...the nuclear reactions that power it winding down
We're watching its death throes
An even bigger, dangerously unstable star
But this one's about to explode
And when a star this big dies...
...it's a hundred times more violent than a supernova.
We've stumbled into the most violent star death of all...
...a hypernova.
The core's collapsed, it's becoming a black hole.
And that's the shock wave, surging through the star...
...ripping its outer layers into space.
Deadly hypernovas, frozen comets...
...scorched planets, white dwarves, red giants
Tiny drops in a vast pool of white light...
...our home galaxy, the Milky Way
We wanted to know where we fit in
Here's our answer.
Civilizations, past and present
Everyone that's ever lived
The smallest bug, the highest mountain...
...all of it invisible, not even a tiny speck.
Our home is a minor planet orbiting an insignificant star.
It is disappeared right now, who would even notice?
And yet, so far, we've found nowhere else we would rather live...
...nowhere we could live
It's only now, far from home...
...that we're beginning to truly appreciate it.
Look at all these stars, hundreds of thousands of them
Surely one of them, more than one, must be capable of supporting life.
Maybe here in this swarm of stars, the Great Cluster
Back in the 1970's, astronomers sent a message in this direction
...detailing the structure of our DNA and our solar system's location
But the message won't arrive here for another 25,000 years.
We haven't found alien life yet
But neither have we found any reason to believe...
...it isn't out there somewhere.
There's an equation devised...
...to estimate the number of other advanced civilizations
The result is startling.
There could be millions of civilizations just in our own galaxy.
Everything we've seen so far is inside the Milk Way
Now we're ready to leave our home galaxy...
...to enter intergalactic space.
Here's our chance to solve the ultimate mystery...
...and experience the moment of creation.
Beyond the Milk Way...
...through the vast expanse between galaxies.
Against all the odds, we've made it to intergalactic space
Out here, there's no horizon in sight.
Even the closest galaxies are hundreds of thousands of light years away
The remains of galaxies ripped apart...
...By the Milky Way's huge gravitational pull...
...scattered among nothing
This is as close as the universe gets to a perfect vacuum.
But even this isn't totally empty.
There are thin wisps of gas, tine traces of dust
And something else, dark matter
So mysterious, we can't see it...
...feel it, taste it, touch it or even measure it.
Yet so common, it could make up over 90 percent...
...of all the matter in the universe.
If dark matter does exist..
...it means there's no such thing as empty space.
Even out here, we're surrounded by matter
We think it exists because of its apparent hold on galaxies
Like this one, the Large Magellanic Cloud
A 6-billion-year journey in today's fastest spacecraft
...160 thousand light years from the Milky Way...
...at the edge of its gravitational reach
This galaxy should spin off into space, but something is holding it here...
...something invisible, powerful, dark matter
Stars, clusters of stars, nebulae...
...it's a vast astronomical treasure trove.
But look at this, it's like a string of gleaming pearls.
It's a fireball...
...expanding out from what must have been a massive explosion.
A supernova.
So bright that when light from the explosion reached Earth 20 years ago...
...it was visible to the naked eye
And so violent, it triggered a string of nuclear reactions
...forcing atoms together, creating new elements...
...gold, silver, platinum, blasting them out into space.
The gold in the ring on you finger...
...was forged in a massive supernova like this...
...trillions of miles away, billions of years ago.
Before we left home, the universe seemed desperate...
...something out there, up in the sky.
But now we know better.
We are the universe, and it is within us
It's comforting to remember as we venture through this abyss.
Further and further
Faster and faster
The Andromeda Galaxy two and half million light years away
It's racing through space...
...everything blown apart, like shrapnel in an explosion.
We're seeing this galaxy as it was...
...when our ape-like ancestors first walked on the African plains
Further through space, and further back in time
Hold on. This doesn't look right
A whole galaxy exploding?
The only thing large enough to cause an explosion on this scale...
...is another galaxy.
It looks like the end of the world
But this galaxy won't die, it will be reborn.
A new shape, perhaps even new stars...
...as dust and gas collide, creating friction, shockwaves...
...triggering the birth of stars.
There's order in this chaos, a pattern behind the infinite variety...
...an endless cycle of birth and death, creation and destruction
It's a pattern woven through the vast fabric of space...
...that binds each of these galaxies
There are billions of galaxies...
...each with billions, even trillions of stars.
Maybe more stars than there are grains of sand...
...on all the beaches on Earth.
We're finally beginning to see the big picture...
...and it's grander than we ever imagined
This galaxy, the huge Pinwheel Galaxy...
...is so far from Earth that if we send a message home now...
...it will take 27 million years to get there.
Who knows whether our species, our planet...
...will still be around to receive it?
We travel on, back through time
Past the point where the dinosaurs were wiped out...
...past the moment where the first creatures crawled onto land
Two billion light years from home.
Closing in on the edge of the universe
Going back to the beginning of time
This isn't a galaxy. It's brighter than a hundred galaxies
A blinding beam of energy surging for trillions of miles.
Something this big, this bright, must be incredibly powerful
Experience tells us, out here, power equals danger
It looks like a quasar, the deadliest thing in the universe
Our journey could be over
The deadliest, most powerful thing in the universe.
A quasar.
A swirling cauldron of superheated gas
This beast has a heart of darkness, a super-massive black hole...
...as heavy as a billion suns.
It's ripping apart whole stars...
...devouring them until they're nothing...
...lost forever from the visible universe
We think, we hope, we pray...
...we've seen the worst the universe can throw at us.
But no one can know what lies ahead
We'll need to go further, go faster
Eight billion light years from home.
More galaxies, but these look different
Ragged, small, close together
We're so far back in time...
...we're seeing these galaxies as they were before the Earth was born
They're still young, still growing.
We're getting close to where and how it all began
Look at the galaxies now.
They're more like primitive plankton floating in a vast dark ocean
Clouds of dust and gas..
...dancing , twirling, merging to make embryonic galaxies.
They're disappearing
We've gone back before the stars were born...
...into a cosmic dark age
And before that, light, the afterglow...
...from the massive explosion that created the known universe
This is it.
We've made it
The edge of universe
...80 Billion trillion miles from home...
...13 and a half billion years ago
The very instant of the Big Bang...
...the most violent, most creative moment in history.
Everything that's ever happened follows from this moment.
Every religion, every culture, has pondered it
But we still don't known what sparked this act of creation or why
This is where our journey ends
...and the universe begins
An infinitely hot, small, dense point erupts
Creating space, time, matter, our universe itself.
First, it's the size of a subatomic particle.
The tiniest traction of a second later
...it's big enough to hold in the palm of your hand
Moments later, it's the size of the Earth.
Today, the light from the Big Bang is still spreading out
You can hear it as a radio hiss
See it as television static.
All the wonders we've seen on our journey...
...are sparks flying out from the Big Bang.
Galaxies, stars, planets...
...all cosmic debris
We go forward through time...
...riding the blast wave
Until we reach another cooling cinder...
...swirling in the afterglow of the Big Bang.
We're back where we started
Home.
Only now can we really know it.
Smaller, more fragile than we ever imagine
Destined to die swallowed by a dying sun
But we shouldn't despair. We should rejoice
We've managed to experience the wonders of the universe
We should celebrate our achievements...
...and enjoy our moment in the sun