All language subtitles for How the Universe Works (2014) - S03E09 - The Search For A Second Earth_track3_[eng]

Narrator:
THE EARTH IS IN DANGER.

FUTURE COSMIC EVENTS

ARE GOING TO BLAST, BURN,
OR RIP US TO SHREDS.

THE UNIVERSE
IS INCREDIBLY VIOLENT.

THERE ARE HUGE EVENTS
GOING ON ALL THE TIME.

Narrator: ONE DAY, LIFE ON EARTH
WILL BECOME IMPOSSIBLE.

Krauss: THERE WILL BE DISASTERS
IN THE FUTURE,

AND ONE OF THEM WILL DESTROY US.

Narrator: TO SAVE MANKIND,

WE'LL HAVE TO FIND
OTHER PLACES TO CALL HOME.

IT REALLY HAS TO BE OUR DESTINY
TO MOVE OFF THE EARTH

IF WE ARE GOING TO SURVIVE.
IT'S AS SIMPLE AS THAT.

WE NEED AN INSURANCE POLICY.

WE MUST DO IT,
AND WE MUST GET STARTED NOW.

Narrator: WE'LL NEED A LIFEBOAT
AND NEW HOMES AMONGST THE STARS,

AND THIS IS HOW WE CAN DO IT.

-- Captions by VITAC --
www.vitac.com

CAPTIONS PAID FOR BY
DISCOVERY COMMUNICATIONS

Narrator: THE EARTH.

AS FAR AS WE KNOW, IT'S THE ONLY
HOME TO LIFE IN THE UNIVERSE.

Thaller: EARTH IS SUCH
AN IDEAL ENVIRONMENT FOR LIFE.

EVERYTHING ABOUT OUR BODIES --
OUR BIOLOGY, OUR CHEMISTRY --

EVOLVED HERE ON EARTH.

WE LITERALLY
ARE ON THE PERFECT SPACESHIP.

Narrator:
BUT OUR PERFECT SPACESHIP

IS CAREENING THROUGH
A COSMIC MINEFIELD.

EVERY 30 MILLION YEARS OR SO,

A NATURAL OR COSMIC DISASTER

HITS THE EARTH SO HARD

THAT MILLIONS OF CREATURES
GO EXTINCT.

EXTINCTION EVENTS TEND TO KILL
OFF THE DOMINANT SPECIES.

[ ROAR ]

AND RIGHT NOW, THAT'S US.

IT'S CERTAINLY TRUE
THAT IN AN EXTINCTION EVENT,

IT'S THE LARGE AND POWERFUL
THAT GET WIPED OUT. THEY GO.

SO YOU KNOW THAT IF THERE'S
AN EXTINCTION EVENT ON EARTH,

WE HUMANS ARE VULNERABLE.

WE'RE IN THE CATEGORY
OF LARGE AND POWERFUL.

Narrator:
THE ONLY WAY FOR HUMANKIND
TO SURVIVE GLOBAL EXTINCTION

IS TO SPREAD OUR GENES
TO MORE THAN ONE PLANET.

Kaku:
WE HAVE NO CHOICE.

IT'S A LAW OF EVOLUTION,
GEOLOGY, AND PHYSICS.

THE ALTERNATIVE
IS DEATH AND EXTINCTION.

Narrator: WE'LL HAVE TO BUILD
A GIANT SPACECRAFT

CAPABLE OF CROSSING
INTERSTELLAR SPACE

AND COLONIZING DISTANT WORLDS
AROUND OTHER STARS.

Oluseyi: YOU WILL ESSENTIALLY
NEED A NEW NOAH'S ARK.

BUT IT'S GONNA BE A SPACE ARK,
AND IT HAS TO ENCAPSULATE

ALL OF THE DIVERSITY OF EARTH
INSIDE THIS ONE SHIP.

Narrator: THE SPACE ARK
WILL HAVE TO BE HUGE,

BIG ENOUGH TO HOUSE
THE THOUSANDS OF PEOPLE NEEDED

TO CREATE A HEALTHY GENE POOL
ON THE NEW PLANETS.

TOO MASSIVE
TO CONSTRUCT ON EARTH,

THE GIANT CRAFT
WILL HAVE TO BE BUILT IN SPACE,

FAR FROM THE PULL
OF EARTH'S GRAVITY.

BUT BUILDING A SHIPYARD IN
THE SKY IS NO SMALL CHALLENGE.

NASA IS TACKLING IT HEAD-ON

WITH A NEW GENERATION
OF HEAVY-LIFT ROCKETS

CALLED THE SLS.

I SEE THE SLS AS A CAPABILITY
THAT'S GOING TO ALLOW US

TO PUT AN INDUSTRIAL BASE
BETWEEN THE EARTH AND THE MOON.

AFTER WE DO THAT,

AND WE'RE OUT THERE ROUTINELY
WORKING IN SPACE,

THAT'S WHEN WE'LL ASSEMBLE

THE CRAFT THAT'LL TAKE US
TO THE STARS.

Narrator:
LES JOHNSON'S JOB IS TO PLAN
THE FUTURE OF SPACE EXPLORATION.

TODAY, HE'S OBSERVING
A TEST-FIRING

OF A 120-SCALE MODEL SLS.

WHEN THE REAL DEAL TAKES OFF
IN 2032,

THE SLS WILL BECOME THE MOST
POWERFUL ROCKET EVER LAUNCHED.

Les: THE SLS IS BIG.

IT'S GONNA GIVE US
THE CAPABILITY

TO TAKE LOTS OF STUFF UP
WITH EACH LAUNCH,

AND IT CAN BE BIG VOLUME.

AND YOU COULD POTENTIALLY LAUNCH
THREE OF THESE BIG ROCKETS

VERSUS PERHAPS 15 OR 20

OF THE OTHER ROCKETS
WE HAVE AVAILABLE TODAY

TO GET THE SAME AMOUNT
OF MATERIAL OUT INTO SPACE.

Narrator:
LES ENVISIONS SLS ROCKETS

TAKING PREFABRICATED UNITS
BEYOND EARTH'S ORBIT,

WHERE SPACE ENGINEERS
WILL ASSEMBLE THEM

INTO A COLOSSAL
INDUSTRIAL WORKSHOP.

MINERS WILL THEN FLY OUT

TO DIFFERENT BODIES
IN THE SOLAR SYSTEM

TO COLLECT THE RAW MATERIALS
NEEDED TO BUILD THE SPACE ARK.

WE'LL HAVE FACTORIES
ON THE MOON,

AND PERHAPS EVEN BEYOND THAT --

ON GIANT ROCKS
INSIDE THE ASTEROID BELT.

ASTEROIDS HAVE A FRACTION
OF EARTH'S GRAVITY.

HERE, IT WILL BE MUCH EASIER
TO BUILD MASSIVE SECTIONS

AND LIFT THEM TO THE ARK
AS IT BEGINS TO TAKE SHAPE.

THE INNER SOLAR SYSTEM
WILL PROVIDE ALL WE NEED

TO MAKE THE GIANT SUPERSTRUCTURE
OF THE SPACE ARK.

BUT THERE'S SOMETHING MISSING.

COLONIZING A DISTANT WORLD
WILL REQUIRE A PROPULSION SYSTEM

FASTER THAN ANYTHING
WE'VE EVER BUILT BEFORE.

Krauss: SPACE IS HUGE.
OUR SOLAR SYSTEM IS HUGE.

I MEAN, EVEN TO GET TO MARS
WOULD TAKE ALMOST A YEAR.

BUT THAT'S NOTHING

COMPARED TO EXPLORING
THE DISTANCE BETWEEN STARS.

THE NEAREST STARS TO OUR SUN
ARE SEVERAL LIGHT-YEARS AWAY.

EVEN LIGHT, THE FASTEST THING
IN THE UNIVERSE,

TAKES SEVERAL YEARS
TO GET THERE.

Narrator:
THE SUN'S CLOSEST NEIGHBOR

IS A TRIPLE-STAR SYSTEM
CALLED ALPHA CENTAURI.

A SPACESHIP
BURNING CONVENTIONAL FUEL

WOULD TAKE TENS OF THOUSANDS
OF YEARS TO GET THERE.

THE CREW WOULD DIE OF OLD AGE
LONG BEFORE THE SHIP ARRIVED.

SO WHAT FUEL TO USE?

SCIENCE FICTION
APPEARS TO HAVE THE SOLUTION,

BUT IT SOUNDS
TOO GOOD TO BE TRUE.

EVERY TREKKIE
IN THEIR HEART OF HEARTS

KNOWS THAT IT'S ANTIMATTER.

ANTIMATTER IS THE FUEL
FOR AN INTERSTELLAR SHIP.

Narrator:
ANTIMATTER IS REAL.

WE CREATE A FEW ATOMS
OF ANTIMATTER EVERY YEAR

IN HIGH-ENERGY
PARTICLE COLLIDERS.

IT'S THE MIRROR IMAGE OF ALL THE
MATTER THAT WE SEE AROUND US,

AND IT HAS AN EXPLOSIVE PROPERTY
THAT WOULD MAKE IT

THE MOST EFFICIENT ROCKET FUEL
EVER CREATED.

HERE'S THE COOL THING
ABOUT ANTIMATTER.

WHEN ANTIMATTER AND MATTER MEET,
THEY ANNIHILATE EACH OTHER.

THAT MEANS THAT
THE MATTER CEASES TO EXIST.

THEY CONVERT INTO PURE ENERGY.

IT'S A 100% EFFICIENT PROCESS.

Narrator:
SCIENTISTS HAVE CALCULATED

THAT A ROCKET
POWERED BY ANTIMATTER

COULD REACH 15%
OF THE SPEED OF LIGHT.

THAT'S FAST ENOUGH TO GET
TO THE MOON IN 8 1/2 SECONDS.

WE WILL HAVE
ALMOST UNLIMITED POWER.

WE COULD TRAVEL ANYWHERE
IN THE UNIVERSE WE WANTED TO.

Narrator: OUR SPACE ARK
COULD REACH ALPHA CENTAURI

IN JUST OVER 28 YEARS,

WELL WITHIN THE LIFETIME
OF ITS HUMAN PAYLOAD.

NOW, THIS SOUNDS LIKE
A GREAT IDEA, RIGHT?

LET'S GET TOGETHER
A LOT OF ANTIMATTER.

LET'S CREATE SOME ANTIMATTER,

AND LET'S COMBINE IT
WITH REGULAR MATTER,

AND WE HAVE
THIS OUTSTANDING ENERGY SOURCE.

BUT ANTIMATTER
HAS A HUGE PROBLEM,

AND THAT IS
EXACTLY WHAT ITS ADVANTAGE IS --

WHEN IT MEETS MATTER, IT'S GOING
TO ANNIHILATE AND CREATE ENERGY.

Narrator:
FILL A CONVENTIONAL FUEL TANK

WITH A SINGLE POUND
OF ANTIMATTER,

AND YOU'LL GET AN EXPLOSION

MORE POWERFUL
THAN 1,000 HIROSHIMA BOMBS.

ANTIMATTER
IS JUST TOO HOT TO HANDLE.

WE NEED A RELIABLE ENERGY SOURCE

THAT CAN POWER OUR STARSHIPS
FOR YEARS AT A TIME.

AND THERE ARE ONLY A FEW
CANDIDATES THAT CAN DO THIS.

AMONG THEM, FUSION POWER --

HARNESSING THE POWER
OF THE SUN ITSELF.

Narrator:
IN THE SUN'S HOT, DENSE CORE,
HYDROGEN ATOMS COLLIDE...

...SMASHING INTO EACH OTHER
WITH SUCH FORCE

THEY FUSE, RELEASING
ENORMOUS AMOUNTS OF ENERGY.

THIS IS NUCLEAR FUSION.

Les: WHAT WE WANT TO DO
IN SPACE TRAVEL

IS MINIATURIZE IT
AND PUT IT IN A SPACECRAFT

AND USE THAT
AS YOUR POWER SYSTEM

AND AS YOUR PROPULSION SYSTEM
FOR DEEP-SPACE EXPLORATION.

Narrator: A FUSION ROCKET

IS STILL TWO-THIRDS THE SPEED
OF ONE POWERED BY ANTIMATTER.

AND BEST OF ALL,
ITS FUEL, HYDROGEN GAS,

CAN BE FOUND IN VAST CLOUDS
IN THE SPACE BETWEEN STARS.

IT WOULD SIMPLY AUTOMATICALLY
FIRE IN OUTER SPACE

USING INTERSTELLAR GAS.

AND, IN PRINCIPLE, IT WOULD
NEVER REQUIRE REFUELING.

Narrator:
OUR FUSION-POWERED SPACE ARK
HEADS FOR ITS FIRST TARGET,

ALPHA CENTAURI,
AT 10% THE SPEED OF LIGHT.

IT WILL TAKE 42 YEARS
TO COMPLETE THE JOURNEY,

AND ITS PRECIOUS LOAD
OF HUMAN PIONEERS

MUST BE DELIVERED SAFE AND WELL.

BUT THE CROSSING MAY BE DEADLY.

OUR VIOLENT COSMOS
HAS A MILLION WAYS TO KILL.

Narrator: A GIANT SPACE ARK
FIRES ITS FUSION ROCKETS.

INSIDE THE SHIP ARE THOUSANDS
OF HUMAN VOLUNTEERS.

THEY'RE ON A ONE-WAY MISSION
TO COLONIZE A DISTANT PLANET.

ONE DAY, WE WILL
HAVE TO MAKE THIS JOURNEY.

IT'S INEVITABLE
THAT WE GO OFF-PLANET.

I THINK WE'RE GONNA HAVE TO
DO IT TO SURVIVE AS A SPECIES.

Narrator:
THE ARK'S FIRST TARGET

IS THE CLOSEST STAR SYSTEM
TO THE SUN, ALPHA CENTAURI.

AND THE JOURNEY WILL BE LONG --
AROUND 40 YEARS.

KEEPING THE CREW FIT AND HEALTHY
IS IMPERATIVE,

BUT IT WON'T BE EASY.

A LOT OF THINGS HAPPEN
TO THE HUMAN BODY

WHEN YOU GO INTO SPACE.

THE MOMENT
YOU BECOME WEIGHTLESS,

YOU INSTANTLY GET
KIND OF A FULL-HEADED FEELING.

YOU GET DIZZY.
THAT CAN MAKE YOU FEEL NAUSEOUS.

Narrator:
LEROY CHIAO SPENT SIX MONTHS

ON THE INTERNATIONAL
SPACE STATION,

LONG ENOUGH TO EXPERIENCE

THE DAMAGING EFFECTS
OF ZERO GRAVITY.

Chiao: YOUR BONES
AREN'T FEELING ANY IMPACT,

SO YOUR BODY DECIDES
IT DOESN'T NEED BONES ANYMORE,

AND IT'LL BEGIN
TO DE-MINERALIZE YOUR BONES.

AND THEN, YOUR MUSCLES,
THROUGH DISUSE --

OF COURSE, THEY'LL NATURALLY
ATROPHY VERY QUICKLY.

Narrator: THE HUMAN BODY EVOLVED
TO LIVE WITH EARTH'S GRAVITY.

WITHOUT IT,

BONES LOSE 2% OF THEIR MASS
FOR EVERY MONTH SPENT IN SPACE.

THE CARDIOVASCULAR SYSTEM
SUFFERS, TOO.

BODY FLUIDS POOL.

HEART RATE
AND BLOOD PRESSURE RISE.

RESISTANCE TRAINING
HELPS REDUCE THE SYMPTOMS.

Chiao: WE'RE SCHEDULED
FOR TWO HOURS OF EXERCISE A DAY

ON THE SPACE STATION TO KEEP
OUR CARDIOVASCULAR SYSTEM FIT,

TO KEEP OUR MUSCLES
AND OUR BONES FIT.

Narrator:
EXERCISING CAN HOLD OFF
THE DANGEROUS WASTING PROCESS.

BUT A 42-YEAR JOURNEY
TO ALPHA CENTAURI

WITHOUT GRAVITY
WOULD BE FATAL.

OBVIOUSLY, WE NEED A PERMANENT
SOLUTION TO WEIGHTLESSNESS.

THERE'S NOTHING TO PREVENT US,
IN THE NEAR FUTURE,

FROM CREATING
ARTIFICIAL GRAVITY.

Narrator:
THE ANSWER IS CENTRIFUGAL FORCE.

IT'S THE FORCE

THAT STICKS DAREDEVIL BIKERS
TO VERTICAL WALLS

AND KEEPS THRILL-SEEKERS GLUED
TO THEIR SEATS IN THEME PARKS.

ROTATION PRODUCES
THIS OUTWARD FORCE,

AND CREATING IT IN A SPACESHIP
WOULD BE RELATIVELY SIMPLE.

BY ROTATING A SPACE CAPSULE,

IT MEANS
THAT THE ASTRONAUTS INSIDE

WILL EXPERIENCE
ARTIFICIAL GRAVITY.

Narrator: SPINNING THE LIVING
QUARTERS AT JUST THE RIGHT SPEED

WILL HOLD OFF
BONE AND MUSCLE WASTING.

BUT AS THEY JOURNEY
DEEP INTO SPACE,

LOW GRAVITY IS THE LEAST OF THE
DANGERS OUR PIONEERS WILL FACE.

Chiao: RADIATION IS PROBABLY
THE BIGGEST CHALLENGE.

WE'RE GONNA BE EXPOSED
TO MUCH HARSHER LEVELS,

MUCH HIGHER LEVELS,
OF RADIATION.

Narrator:
THE SUN'S SURFACE SHOOTS OUT

A CONSTANT STREAM
OF DANGEROUS CHARGED PARTICLES,

PROTONS AND ELECTRONS

TRAVELING AT CLOSE
TO A MILLION MILES AN HOUR.

Oluseyi: THESE THINGS
WILL BREAK YOUR DNA.

THEY'LL CAUSE CANCER,
AND THEY WILL KILL YOU.

Narrator:
THE EARTH'S MAGNETOSPHERE

AND THE ATMOSPHERE
ABOVE OUR HEADS

PROTECTS US FROM THE WORST
OF THIS RADIATION.

BUT FAR FROM THE EARTH,

THE PIONEERS
WILL FACE RADIATION HEAD-ON.

THAT REALLY IS
THE BIGGEST TECHNICAL BARRIER

TO MANKIND SENDING PEOPLE OUT
FARTHER AND DEEPER INTO SPACE.

IT'S NOT PROPULSION. IT'S NOT
COMPUTERS OR NAVIGATION.

IT'S HOW DO WE
KEEP PEOPLE HEALTHY?

Narrator: BEYOND THE BOUNDARY
OF OUR SOLAR SYSTEM,

THE RADIATION THREAT GETS WORSE.

CHARGED PARTICLES
COME AT YOU EVEN FASTER.

Thaller: IN SOME CASES,
THERE ARE SINGLE PROTONS

THAT ACTUALLY PACK
AS MUCH OF A PUNCH

AS A 100-MILE-AN-HOUR FASTBALL.

Narrator:
THESE COSMIC RAYS ARE JOINED
BY AN EVEN DEADLIER FORCE --

GAMMA RAYS, BLASTED OUT
BY VIOLENT, COSMIC EVENTS.

ALL OF THE COSMIC PHENOMENA,
FROM STARS EXPLODING...

...TO BLACK HOLES EATING UP
LARGE PARTS OF GALAXIES...

...PRODUCE RADIATION

AND PARTICLES
THAT ARE INCREDIBLY ENERGETIC.

YOU'VE NEVER SEEN
THESE PARTICLES BEFORE.

YOU BODY'S NOT ADAPTED TO THEM.

AND THEY COME AT YOU
ALL THE TIME,

AND THEY'RE VERY HIGH-ENERGY.

Narrator:
GALACTIC, COSMIC RADIATION

WILL RIP THROUGH THE CELLS
OF OUR HUMAN CARGO...

...LIQUEFYING THEIR BODIES.

THE ONLY HOPE IS TO SOMEHOW
SHIELD THE SPACECRAFT.

IN SCIENCE FICTION,

STARSHIPS CREATE
A PROTECTIVE MAGNETIC BUBBLE

SIMILAR TO THE MAGNETIC FIELD
THAT PROTECTS THE EARTH.

BUT A DEFLECTOR SHIELD

WOULD TAKE A HUGE AMOUNT
OF ENERGY TO SUSTAIN.

AND LIKE ANY ELECTRICAL DEVICE,
IT WOULD BE PRONE TO FAILURE.

THE SAFEST OPTION
IS TO GO LOW-TECH,

COATING THE SHIP WITH A THICK
LAYER OF PHYSICAL SHIELDING.

Chiao: SHIELDING
IS NOT A SIMPLE PROBLEM.

IT'S NOT JUST A MATTER

OF BRINGING A BUNCH OF LEAD
OR ANYTHING LIKE THAT.

IN FACT, WHAT YOU FIND IS THAT
IF YOU DO SOMETHING LIKE THAT,

IT ABSORBS THE RADIATION,

AND THEN IT RE-EMITS IT
IN A MORE DANGEROUS FORM.

Narrator:
METALS WON'T WORK.

BUT SCIENTISTS HAVE COME UP
WITH A BRILLIANT ALTERNATIVE.

Thaller: IN FACT, ONE OF THE
BEST SHIELDS FROM COSMIC RAYS

IS SOMETHING SIMPLE -- WATER.

AND IT'S ACTUALLY SOMETHING
YOU NEED TO BRING WITH YOU

AS YOU VENTURE
INTO INTERSTELLAR SPACE.

Narrator:
THE HYDROGEN ATOMS IN WATER
ABSORB HIGH-ENERGY PARTICLES.

AND, IN SUFFICIENT VOLUME,
WATER CAN ALSO BLOCK GAMMA RAYS.

THE LIVING QUARTERS OF THE ARK

WILL HAVE A THICK OUTER SKIN
FILLED WITH THE SHIP'S WATER

AND, OUTSIDE THAT, A SECOND SKIN

FILLED WITH THE SHIP'S HYDROGEN
SUPPLY FOR ITS FUSION ENGINES.

OUR ASTRONAUTS ARE NOW SAFE
FROM RADIATION SICKNESS.

AND WITH ARTIFICIAL GRAVITY,
THEIR BODIES WILL STAY STRONG.

THE DEADLIEST THREAT NOW...

EACH OTHER.

Narrator: A COSMIC CATASTROPHE

WILL ONE DAY WIPE US
FROM THE FACE OF THE EARTH.

TO SAVE MANKIND, WE'LL NEED
TO ESCAPE TO THE STARS

IN A GIANT SPACE ARK
IN SEARCH OF A NEW HOME.

ITS PRECIOUS HUMAN CARGO WILL BE
KEPT IN TOP PHYSICAL CONDITION

WITH ARTIFICIAL GRAVITY
AND HYDROGEN-RICH SHIELDING.

BUT WHAT ABOUT
THEIR MENTAL HEALTH?

ONE OF THE BIGGEST CHALLENGES
FOR PEOPLE IN SPACE

ARE THE PEOPLE.

TAKING PEOPLE,
PUTTING THEM IN A TIN CAN

IN AN INCREDIBLY DANGEROUS
ENVIRONMENT,

HAVING THEM GET ALONG WITH
EACH OTHER FOR MONTHS OR YEARS

AND STAY ALIVE
THROUGH THE JOURNEY

IS GOING TO BE
AN ENORMOUS CHALLENGE.

Krauss: WE KNOW
WHEN PEOPLE GO ON SUBMARINES,

THAT THEY HAVE TO BE
VERY CAREFULLY TESTED.

AND THOSE SUBMARINES
GO OUT FOR MISSIONS

THAT CERTAINLY DON'T LAST YEARS.

Narrator: WE CAN'T
START A NEW CIVILIZATION

WITH A CREW RAVAGED
BY COSMIC BOREDOM, INFIGHTING,

AND MENTAL ILLNESS.

IT WOULD BE BETTER

IF THE ENTIRE CREW
WERE UNCONSCIOUS.

Krauss: ONE POSSIBILITY --
WHICH, OF COURSE, AGAIN,

IS A POSSIBILITY
IN SCIENCE FICTION --

IS TO HAVE PEOPLE BE ASLEEP
DURING MOST OF IT.

Thaller: COULD YOU PUT PEOPLE
INTO AN INDUCED COMA

AND THEN WAKE THEM UP IN TIME
TO GO DO THEIR SCIENCE MISSION?

IT MIGHT BE AN EASIER THING
TO DO

THAN TO SAY, "WELL,
NOW YOU JUST SIT STILL

FOR THE NEXT 10 YEARS."

Narrator: THE CLOSEST WE'VE COME
TO SUSPENDED ANIMATION

IN TODAY'S WORLD

IS STORING HUMAN EMBRYOS
IN LIQUID NITROGEN.

BUT COULD WE REALLY
SAVE THE HUMAN RACE

WITH TEST-TUBE BABIES?

BECAUSE OF THE ENORMOUS HURDLES
FACING SPACE TRAVEL,

SOME PEOPLE
HAVE ADVANCED THE IDEA,

"WELL, WHY DO WE HAVE TO
SEND HUMANS INTO OUTER SPACE?

WHY NOT SEND EMBRYOS
OR SPERM AND EGG CELLS?"

Narrator: IN THEORY, WE COULD
TRANSPORT FROZEN EMBRYOS

ACROSS VAST DISTANCES OF SPACE,

SIDE-STEPPING THE NEED FOR FOOD

OR COMPLICATED
LIFE-SUPPORT SYSTEMS.

Kaku:
THEY COULD WITHSTAND

THE RIGORS OF SPACE TRAVEL
AND WEIGHTLESSNESS,

BUT HOW WILL THEY BE SOCIALIZED?

Krauss: YOU PUT A BABY
IN A SINGLE PLACE ALONE,

THEY DON'T LEARN HOW TO READ.
THEY WOULDN'T SURVIVE, IN FACT.

WE'RE VERY DEPENDENT.
WE ARE SOCIAL BEINGS.

Narrator: WE WOULD HAVE TO
DEVELOP INTELLIGENT ROBOTS

TO HATCH THE EMBRYOS

AND THEN TEACH THEM
WHAT IT MEANS TO BE HUMAN.

IT'S CONCEIVABLE THAT PERHAPS
100 YEARS INTO THE FUTURE,

WE WILL HAVE ROBOT NANNIES

THAT CAN INCORPORATE
THE LAWS OF SOCIAL INTERACTION.

Narrator: COULD A ROBOT
REALLY RAISE A CHILD?

OR, IN OUR RUSH
TO SAVE HUMANITY,

WILL WE WIND UP FORGETTING
WHAT IT MEANS TO BE HUMAN?

RAISING HUMAN EMBRYOS
MAY BE TOO MUCH OF A GAMBLE.

SO COULD WE FREEZE
ADULTS INSTEAD

WITHOUT AFFECTING THEIR HEALTH?

IT'S A MUCH BIGGER CHALLENGE,
BUT NATURE HAS ALMOST SOLVED IT.

Plait:
A LOT OF ANIMALS ON EARTH

WILL GO INTO SUSPENDED ANIMATION
OR HIBERNATION

WHEN CONDITIONS GET BAD.

AND IN SOME CASES, THEY CAN
STAY THAT WAY FOR A LONG TIME.

Narrator:
THE ALASKAN WOOD FROG

SURVIVES WHOLE WINTERS
FROZEN IN ICE.

AT SUBZERO TEMPERATURES,

ITS METABOLISM SLOWS
AND EFFECTIVELY SHUTS DOWN.

WHEN THE ICE THAWS,
THE FROGS REANIMATE...

...AND HOP OFF
AS THOUGH NOTHING HAPPENED.

COULD HUMANS EVER DO
THE SAME THING?

WHEN YOU FREEZE SOMEBODY ALIVE,

THERE ARE ICE CRYSTALS
WHICH FORM

WHICH BEGIN TO EXPAND,
RUPTURING THE CELLS,

AND TURN CELLS INTO MUSH.

Narrator: SO HOW DO THE FROGS
SURVIVE THE DEEP FREEZE?

THE ANSWER IS THEY HAVE
AN ANTIFREEZE IN THEIR BLOOD,

AND THAT IS GLUCOSE.

SO EVEN THOUGH THEIR SURROUNDING
ENVIRONMENT IS SOLID ICE,

INSIDE, THEIR CELLS ARE LIQUID.

THE PROBLEM WITH HUMANS IS,

THAT AMOUNT OF ANTIFREEZE
WOULD KILL US.

[ MONITOR BEEPING ]

Narrator: DEEP-FREEZING HUMANS
ISN'T GOING TO WORK.

BUT TO HIBERNATE, WE MAY NOT
HAVE TO CHILL THAT LOW.

IN PITTSBURGH,

SURGEONS HAVE DEVELOPED
A GROUNDBREAKING TECHNIQUE

USING CHILLED SALINE SOLUTION

TO RAPIDLY LOWER
THEIR PATIENTS' BODY TEMPERATURE

TO JUST A FEW DEGREES
ABOVE FREEZING.

AT THIS TEMPERATURE,
CELLULAR ACTIVITY STOPS.

JUST LIKE THE WOOD FROGS,

THE PATIENTS ARE EFFECTIVELY
IN SUSPENDED ANIMATION.

Krauss: IN OPERATING ROOMS,
WE CAN COOL PEOPLE DOWN

AND PUT THEM IN
AN ARTIFICIAL COMA FOR A WHILE.

SO, IT SOUNDS GOOD,

AND LIKE EVERYTHING ELSE,
IT'S WORTH EXPLORING.

[ MONITOR BEEPING ]

Narrator:
WHETHER THROUGH FREEZING EMBRYOS

OR PUTTING ADULTS
INTO A COLD, DEEP SLEEP,

SUSPENDED ANIMATION
MAY BE THE BEST BET

FOR KEEPING
OUR PRECIOUS HUMAN CARGO ALIVE

ON THE LONG TRIP
TO ALPHA CENTAURI.

BUT WHAT IF THEY GET THERE AND
FIND THERE'S NO PLACE LIKE HOME?

Narrator: A SPACESHIP
FILLED WITH HUMAN VOLUNTEERS

APPROACHES THE TRIPLE-STAR
SYSTEM, ALPHA CENTAURI.

THE CREW HOPES TO FIND
THE FIRST OF MANY NEW WORLDS

FOR MANKIND TO CALL HOME.

BUT WHICH, IF ANY,
OF THESE STARS

WILL HAVE
THE RIGHT KIND OF PLANETS?

WE WANT TO FIND A HOME

THAT'S AS SIMILAR TO EARTH
AS WE CAN POSSIBLY FIND,

BECAUSE WE'RE FINE-TUNED
FOR THIS PLANET.

WE'RE JUST FINE-TUNED
FOR THIS SURFACE GRAVITY.

WE'RE FINE-TUNED
FOR THIS ATMOSPHERE,

THIS RADIATION ENVIRONMENT.

Narrator: THE STARS FILL
THE SPACECRAFT'S DISPLAYS,

AND SOON, THE OUTLINE OF PLANETS
WILL BE VISIBLE.

THE BRIGHTEST OF THE TRIO
IS ALPHA CENTAURI "A."

IT'S SLIGHTLY BIGGER AND
SLIGHTLY BRIGHTER THAN OUR SUN,

THROWING MORE HEAT
INTO THE SPACE AROUND IT.

ITS SMALLER, COOLER NEIGHBOR,
ALPHA CENTAURI "B,"

LIES SO CLOSE,
GRAVITY PULLS THE TWO STARS

INTO A WIDE,
SLOW BINARY ORBIT...

...ROTATING ONCE EVERY 80 YEARS.

THAT'S BAD NEWS
FOR OUR PIONEERS.

PLANETS RARELY FORM
STABLE ORBITS

AROUND WIDE BINARY SYSTEMS,

SO THERE'S LITTLE CHANCE OF
FINDING A PLACE TO SETTLE HERE.

BUT THE THIRD STAR IN THE TRIO
OFFERS HOPE.

PROXIMA CENTAURI IS A RED DWARF
OR "M" DWARF STAR,

TOO SMALL AND DIM TO BE SEEN
FROM EARTH WITH THE NAKED EYE.

YET ASTRONOMERS
HAVE FOUND EARTH-LIKE PLANETS

AROUND THIS TYPE OF STAR
THROUGHOUT THE MILKY WAY GALAXY.

WE'RE FINDING THAT RED DWARFS
ARE IDEAL IN A NUMBER OF WAYS.

IN PARTICULAR, THEY SEEM TO BE
ABSOLUTELY TEEMING

WITH EARTH-SIZED PLANETS.

Narrator: ASTRONOMERS
HAVE ALREADY DISCOVERED

ONE EARTH-SIZED PLANET
AROUND PROXIMA CENTAURI.

IT ORBITS TOO CLOSE TO THE STAR
TO SUSTAIN HUMAN LIFE,

BUT THERE'S A GOOD CHANCE

IT MAY HAVE SISTER PLANETS
THAT CAN.

John: IF WE WERE TO LOOK UP
INTO THE NIGHT SKY

AND LOOK AT
THE NEAREST "M" DWARF STAR --

SAY, PROXIMA CENTAURI --

I WOULD EXPECT TO SEE

A SYSTEM OF THREE TO SIX
VERY SMALL PLANETS

IN EXTREMELY COMPACT ORBITS,

MEANING ORBITAL PERIODS
OF ONLY A FEW DAYS.

Narrator: PROXIMA CENTAURI
MAY WELL BE HOME

TO A ROCKY PLANET
IDEAL FOR LIFE,

WITH A THICK ATMOSPHERE,
WARM, LIQUID OCEANS,

AND A STRONG MAGNETOSPHERE
TO PROTECT IT --

THE PERFECT REFUGE FOR MANKIND
TO SET UP OUR FIRST NEW HOME.

BUT WHAT IF WE FIND A PLANET

THAT'S A LITTLE LESS
THAN PERFECT --

TOO COLD, PERHAPS,
WITH TOO MUCH GRAVITY...

OR MAYBE
THE WRONG KIND OF ATMOSPHERE?

Kaku:
WE ARE GENETICALLY PROGRAMMED
TO THRIVE ON THE PLANET EARTH

WITH A SPECIFIC AMOUNT
OF OXYGEN,

A SPECIFIC AMOUNT
OF CARBON DIOXIDE,

AND A CERTAIN WEIGHT.

HOWEVER, ONCE WE LAND
ON A DISTANT PLANET,

WE'RE GONNA HAVE TO
CHANGE OUR BODIES

SO THAT WE CAN THRIVE
IN DIFFERENT ENVIRONMENTS.

Oluseyi: WE'RE GONNA HAVE TO
BE ABLE TO ENGINEER OURSELVES.

WE'RE GONNA HAVE TO BE ABLE
TO EVOLVE OURSELVES RAPIDLY.

THAT MAY MEAN TAKING GENES
FROM OTHER LIFE FORMS

TO GIVE OURSELVES
SOME PROPERTY THAT WE NEED.

THAT MIGHT JUST BE
THE BEST SOLUTION.

Narrator: SCIENTISTS
HAVE SEARCHED HIGH AND LOW

TO FIND THE ULTIMATE GENES
FOR SURVIVAL IN SPACE,

AND THEY MAY HAVE FOUND THEM

IN A CREATURE
NO BIGGER THAN A GRAIN OF SAND.

RIGHT NOW AT NASA,
WE'RE DOING EXPERIMENTS

ON TINY, LITTLE ANIMALS
CALLED TARDIGRADES.

Narrator:
TARDIGRADES ARE TOUGH.

THEY CAN SURVIVE
A RANGE OF TEMPERATURES

FROM FREEZING TO BOILING POINT.

THEY CAN LIVE WITHOUT FOOD
OR WATER FOR A DECADE OR MORE.

AND, CRUCIALLY, WHEN THEIR DNA
GETS DAMAGED BY RADIATION,

IT REPAIRS ITSELF.

A TINY, LITTLE, MICROSCOPIC
THING CAN SURVIVE MORE RADIATION

THAN WOULD KILL
A HERD OF ELEPHANTS.

SOMEHOW, THE DNA
KNOWS HOW TO REPAIR ITSELF.

WE'RE TRYING TO FIGURE OUT

HOW WE COULD MODIFY HUMAN DNA
TO DO THE SAME THING.

Narrator: ONE DAY,
DNA FROM THESE TINY CREATURES

MAY ALLOW US
TO SET FOOT ON A PLANET

BATTERED BY RADIATION
FROM ITS PARENT STAR.

AND GENETIC TINKERING
MAY HOLD THE KEY TO MUCH MORE,

ALLOWING US TO COLONIZE

A MULTITUDE OF HOSTILE,
ALIEN WORLDS.

Kaku: IF THE PLANET HAS
A LARGER GRAVITATIONAL FIELD,

WE MAY HAVE TO INCREASE
THE STRENGTH OF OUR BONES

AND THE STRENGTH OF OUR MUSCLES
SO WE DON'T COLLAPSE

EVERY TIME WE WALK ON
THE SURFACE OF A LARGE PLANET.

Narrator: WE COULD EVEN ADAPT
TO DIFFERENT ATMOSPHERES.

Kaku:
IF WE WERE TO ARRIVE ON A PLANET

THAT HAS A DIFFERENT
OXYGEN LEVEL,

DIFFERENT CARBON DIOXIDE LEVEL,

WE MAY HAVE TO ALTER
OUR METABOLISM RATE.

Thaller:
WE ARE BEGINNING TO TAKE CONTROL
OF OUR OWN EVOLUTION.

WE ARE DESIGNING GENE THERAPIES.

WE ARE FINDING WAYS
TO MODIFY OUR BIOLOGY.

THERE'S A WONDERFUL CHANCE HERE

TO REALLY TAKE CONTROL
OF OUR OWN DESTINY

AND DRIVE OURSELVES
TO THE STARS.

Krauss: WHO KNOWS WHAT THE
FUTURE ASTRONAUT WILL LOOK LIKE?

BUT I STRONGLY SUSPECT THAT
THEY WON'T LOOK LIKE YOU OR ME.

Narrator: IF WE FIND HABITABLE
WORLDS AROUND PROXIMA CENTAURI,

A SHUTTLE FULL
OF GENETICALLY ALTERED PIONEERS

WILL BE DISPATCHED
TO THE SURFACE

IN ORDER TO START
A NEW HUMAN CIVILIZATION.

BUT THIS IS JUST THE FIRST STAGE
OF A MUCH BIGGER PLAN.

WE MUST CONTINUE
TO SEARCH OUT MORE WORLDS,

TRAVELING EVER DEEPER AND FASTER
INTO THE MILKY WAY.

Narrator: ONE DAY,
A COSMIC EVENT

IS GOING TO HIT THE EARTH
SO HARD,

IT WILL WIPE OUT
EVERY HUMAN ON THE PLANET.

[ RUMBLING ]

IF WE'RE GONNA LIVE ON
INDEFINITELY INTO THE FUTURE,

HUMAN BEINGS ARE GONNA HAVE TO
LEAVE PLANET EARTH.

Narrator: OUR ONLY HOPE
IS TO BUILD A SPACE ARK

THAT WILL TAKE US TO NEW WORLDS
AROUND DISTANT STARS.

Kaku:
LIFE IS FRAGILE,

AND THAT'S WHY I BELIEVE

WE SHOULD BE
AT LEAST A TWO-PLANET SPECIES.

Narrator: THE FIRST TARGET
WAS BY FAR THE EASIEST.

IT TOOK 42 YEARS FOR OUR SPACE
ARK TO REACH PROXIMA CENTAURI

USING FUSION-POWERED ENGINES.

BUT NOW THE ARK MUST MOVE ON TO
FIND EVEN MORE DISTANT WORLDS.

THE CREW CAN BE HELD
IN SUSPENDED ANIMATION,

BUT THEY'LL STILL DETERIORATE
WITH EACH PASSING YEAR.

WE NEED TO GO FASTER,
CLOSER TO THE SPEED OF LIGHT.

BUT THERE'S A SMALL PROBLEM --
THE LAWS OF PHYSICS.

WHAT ALBERT EINSTEIN FIGURED OUT

IS THAT IF YOU START TRAVELING
NEAR THE SPEED OF LIGHT,

THINGS GET A LITTLE BIZARRE.

AS YOU GET NEAR THE SPEED
OF LIGHT, YOUR MASS INCREASES,

MEANING THAT YOU HAVE TO HAVE
MORE ENERGY TO KEEP YOU GOING.

Krauss: BY THE TIME YOU GET TO
NEAR THE SPEED OF LIGHT,

ALL THE FUEL
TURNS INTO INCREASING THE MASS.

SO ALL THE FUEL

THAT, BEFORE, WOULD'VE
INCREASED THE SPEED A LOT,

DOESN'T INCREASE THE SPEED
AT ALL.

IT JUST INCREASES THE MASS.

EVENTUALLY,
YOU DON'T SPEED UP AT ALL.

YOU JUST GET HEAVIER AND HEAVIER
AS YOU SHOOT OUT PROPELLANT.

Narrator:
PHYSICS WON'T ALLOW US

TO TRAVEL THROUGH SPACE
AT THE KIND OF SPEEDS WE NEED.

BUT THERE'S A LOOPHOLE

THAT MAY ALLOW US
TO CUT THROUGH HYPERSPACE

AND REACH DISTANT PLANETS
A WHOLE LOT FASTER.

Thaller: EINSTEIN SHOWED US
THAT SPACE ITSELF

CAN EXPAND FASTER
THAN THE SPEED OF LIGHT.

SPACE AND TIME
IS NOT NOTHING.

THERE'S A SUBSTANCE TO IT --
A FABRIC, IF YOU WILL.

AND YOU CAN STRETCH IT,
AND YOU CAN BEND IT.

Narrator: IN SCIENCE FICTION,
GALACTIC TRAVELERS

MANIPULATE THE FABRIC
OF SPACE-TIME USING WARP DRIVES,

CROSSING THE COSMOS
IN MINUTES, NOT MILLENNIA.

IMAGINE YOU'RE IN A ROOM,
AND THERE'S A CARPET.

AND YOU NEED TO GET
TO THE OTHER SIDE OF THE ROOM.

ONE THING YOU CAN DO IS YOU CAN
TAKE THE CARPET AND FOLD IT UP

AND BRING ALL OF IT
CLOSE TO YOU,

THEN STEP OVER THE FOLDED CARPET

AND THEN LET IT
UNFOLD BEHIND YOU.

AND NOW YOU'VE MOVED
ACROSS THE ROOM REALLY QUICKLY.

Narrator: IT WOULD TAKE
A COLOSSAL AMOUNT OF ENERGY

TO WARP ALL THE SPACE BETWEEN
YOU AND YOUR DESTINATION,

FAR MORE THAN WE COULD EVER HOPE
TO GENERATE.

BUT MODERN PHYSICS SAYS
THE WARP DRIVE IS POSSIBLE,

IF YOU ONLY WARP THE SPACE
SURROUNDING THE SHIP.

SO, WE KNOW THAT SPACE EXPANDS,
AND SPACE CAN ALSO CONTRACT.

SO, IF YOU HAVE A SHIP,

AND YOU CONTRACT SPACE
IN FRONT OF YOU

AND EXPAND SPACE BEHIND YOU,
YOU COULD CREATE A WARP BUBBLE.

AND IT'S BEEN
THEORETICALLY SHOWN

THAT YOU COULD MOVE TO UP TO
10 TIMES THE SPEED OF LIGHT.

Narrator:
THIS NEW-GENERATION WARP DRIVE
CREATES A WAVE IN SPACE-TIME

THAT TRAVELS FASTER
THAN THE SPEED OF LIGHT,

CARRYING THE SHIP ALONG WITH IT
LIKE A SURFER RIDING A WAVE.

MATHEMATICIANS
HAVE LOOKED AT THE NUMBERS,

AND A NEW-GENERATION WARP DRIVE
WOULD WORK ON PAPER.

NOW NASA WANTS
TO GET IT TO WORK IN THE LAB.

White: IS IT IMPOSSIBLE,
OR IS IT PLAUSIBLE?

I THINK WE'RE IN THAT CATEGORY
OF STARTING TO THINK ABOUT,

"WE'VE GOT
SOME PLAUSIBILITIES HERE.

"LET'S GO SEE IF WE CAN'T
DO SOME SCIENTIFIC EFFORTS

AND SEE VALIDATION
OF THE MATH AND PHYSICS."

Narrator: HAROLD WHITE
IS PLANNING A FUTURE EXPERIMENT

TO SEE IF HE CAN WARP SPACE
ON A MICROSCOPIC SCALE.

HE HOPES TO CONCENTRATE ENERGY
INTO A SINGLE POINT IN SPACE

AND THEN MEASURE THE PROGRESS
OF LASER LIGHT CROSSING IT.

IF THE LIGHT COMPLETES
THE JOURNEY FASTER THAN NORMAL,

HE'LL HAVE SUCCEEDED
IN WARPING SPACE-TIME.

EVERYBODY ALWAYS ASKS ME ABOUT,

"WHEN'S THIS GONNA BE READY
TO BOLT ONTO A SPACECRAFT?"

AND THERE'S A LOT OF SCIENCE
WE NEED TO DO FIRST.

Plait: WE'RE ONLY JUST NOW
STARTING TO LOOK INTO THIS.

WE DON'T KNOW
IF IT'S GONNA WORK OR NOT.

WE MIGHT AS WELL FIGURE IT OUT.
IF IT DOES -- BOOM.

AND IF IT DOESN'T -- WELL, WE'VE
LEARNED SOMETHING INTERESTING

ABOUT MATH AND SCIENCE
AND THE WAY THE UNIVERSE WORKS.

Narrator:
A WARP-DRIVE WOULD FIRE US

TO PROXIMA CENTAURI
IN JUST FIVE MONTHS...

AND TO THE 50 STARS BEYOND
IN JUST A FEW YEARS.

BUT THAT'S STILL
JUST OUR GALACTIC BACKYARD.

A WARP TRIP
TO THE FAR SIDE OF THE MILKY WAY

WOULD TAKE 10,000 YEARS,

AND A TRIP BEYOND IT
TO THE CLOSEST GALAXIES,

HUNDREDS OF THOUSANDS OF YEARS.

ON THE SCALE OF THE UNIVERSE,

EVEN A WARP-DRIVE
SEEMS PATHETICALLY SLOW.

BUT THERE IS ONE LAST HOPE.

ANOTHER WAY TO GO FASTER
THAN THE SPEED OF LIGHT

IS TO DRILL A HOLE
IN THE FABRIC OF SPACE AND TIME.

THIS IS CALLED A WORMHOLE.

Narrator: A WORMHOLE
IS A THEORETICAL TUNNEL,

A RIP THROUGH THE FABRIC
OF SPACE-TIME,

CONNECTING TWO DISTANT POINTS.

IT'S CREATED

BY HUGE CONCENTRATIONS OF MASS
WARPING SPACE-TIME.

THINK OF ALICE'S LOOKING GLASS.

YOU PUT YOUR HAND
THROUGH THE LOOKING GLASS,

AND YOUR HAND WINDS UP
ON THE OTHER SIDE OF THE GALAXY.

Narrator:
IF OUR SPACECRAFT COULD ENTER
THIS COSMIC SHORTCUT,

WE COULD JUMP THOUSANDS OF YEARS
IN AN INSTANT.

THE ONLY TROUBLE IS ASTRONOMERS
HAVE NEVER SEEN ONE,

AND ATTEMPTING TO CREATE ONE
WOULD BE FATAL.

TO BEND SPACE AT EITHER MOUTH OF
THE WORMHOLE TO MAKE A TUNNEL,

YOU HAVE TO PRODUCE
HUGE AMOUNTS OF MASS.

BUT MASS IS ATTRACTIVE.

AND WE CAN PROVE THAT
IF NORMAL MASS IS ALL YOU HAVE,

THAT EITHER END OF THE WORMHOLE

WILL COLLAPSE TO FORM
A BLACK HOLE IN A TIME-SCALE

SHORTER THAN IT WOULD TAKE YOU
TO GO THROUGH THE WORMHOLE.

I DON'T THINK WORMHOLES
ARE EVER GONNA WORK

AS A WAY OF TRANSPORTATION.

BUT YOU KNOW WHAT?
TYPICALLY, THOSE PEOPLE WHO SAID

THAT SOMETHING COULDN'T HAPPEN
IN SCIENCE

TURNED OUT TO BE WRONG.
SO I TAKE THAT BACK.

I THINK IT'S UNLIKELY,
BUT IT MAY HAPPEN.

Narrator: WARP DRIVES AND
WORMHOLES ARE DISTANT DREAMS.

FOR NOW, FUSION IS THE LIKELY
FUEL TO TAKE US TO THE STARS.

BUT IT MAY TAKE MILLIONS
OF YEARS FOR A GIANT SPACE ARK

TO COLONIZE ENOUGH PLANETS
TO GUARANTEE OUR SURVIVAL.

THE ONLY WAY TO GO FASTER
WITH FUSION

IS TO MAKE OUR SPACE ARK
MUCH SMALLER --

SO SMALL, IN FACT, THERE'D BE
NO ROOM FOR PEOPLE INSIDE.

SO IS THIS REALLY GAME OVER,

OR COULD WE SAVE HUMANITY
WITHOUT HUMANS?

Narrator: NOT SO LONG AGO,
ASTRONOMERS WEREN'T SURE

IF THE STARS THEY SAW
IN THE NIGHT SKY

HAD PLANETS ORBITING THEM.

PERHAPS THE SUN WAS UNIQUE,

AND THE EARTH ALONE
IN THE MILKY WAY.

BUT OVER THE LAST 20 YEARS,

WE'VE REVEALED
A MIND-BLOWING TRUTH.

IT SEEMS THAT A LARGE FRACTION
OF STARS IN THE GALAXY

HAVE PLANETS.

AND, IN FACT, MANY OF THOSE
STARS HAVE MULTIPLE PLANETS.

Narrator:
THESE EXOPLANETS RANGE IN SIZE

FROM GAS-GIANT PLANETS
BIGGER THAN JUPITER

TO ROCKY WORLDS LIKE THE EARTH.

AND THEY'RE EVERYWHERE WE LOOK.

Marcy:
OUR PLANET EARTH IS NOT UNIQUE.

IT'S NOT EVEN RARE.

THERE ARE TONS, HOARDS,
FLOCKS, IF YOU WILL,

OF OTHER EARTH-LIKE PLANETS
OUT THERE

FLUTTERING AROUND
THE OTHER STARS.

SOME STARS PROBABLY HAVE
MULTIPLE EARTHS ORBITING THEM.

THAT'S HOW COMMON
EARTH-LIKE PLANETS ARE.

Thaller: LOOK INTO THE NIGHT SKY
AND COUNT FIVE STARS.

ONE OF THOSE STARS HAS AN
EARTH-SIZED PLANET AROUND IT,

MAYBE OUR NEXT HOME.

Narrator: APPLY WHAT WE'VE FOUND
TO THE REST OF THE MILKY WAY,

AND THE RESULTS
ARE STAGGERING...

AROUND SUN-LIKE STARS, UP TO
11 BILLION WARM, WET EARTHS --

AROUND RED DWARF STARS,
ANOTHER 22 BILLION,

AND GAS-GIANT EXOPLANETS
MAY BE HOME

TO TENS OF BILLIONS MORE
POTENTIAL EARTHS

IN THE FORM
OF HABITABLE EXOMOONS.

THERE ARE MANY
EARTH-LIKE PLANETS

THAT WE'RE GONNA HAVE
AS OPTIONS OF PLACES TO GO,

ALMOST SORT OF A MENU
SPREAD OUT IN FRONT OF US.

Narrator: CLEARLY, FINDING
NEW EARTHS IS NOT THE PROBLEM.

THE PROBLEM IS GETTING THERE.

Thaller: THE UNIVERSE IS
ACTUALLY KIND OF TANTALIZING US.

EARTH-LIKE PLANETS ARE COMMON.
THEY'RE ALL OVER THE PLACE.

BUT THEY'RE SO FAR AWAY THAT
WITH OUR CURRENT TECHNOLOGY,

WE CANNOT IMAGINE
HOW TO GET THERE.

Narrator: A GIANT SPACE ARK,
POWERED BY FUSION ENGINES

AND FILLED WITH THOUSANDS
OF HUMAN VOLUNTEERS,

SHOULD ALLOW US TO COLONIZE
HABITABLE WORLDS NEAR OUR SUN.

BUT TO GO BEYOND THAT, TO THE
FAR REACHES OF THE MILKY WAY,

WE NEED PLAN "B."

ONE RADICAL SOLUTION WOULD BE

TO SEND MINIATURE ROBOTS
TO DISTANT PLANETS

INSTEAD OF HUMANS.

Thaller: WHEN I THINK
ABOUT HOW MUCH WE'RE LEARNING

ABOUT THE HUMAN BRAIN
AND HOW IT WORKS --

AND THERE'S STILL
A LONG WAY TO GO --

IT DOES SEEM TO ME FAIRLY
INEVITABLE THAT SOMEDAY,

WE'LL BE ABLE TO PUT
ALL OF OURSELVES INTO A ROBOT.

Krauss: NOW, YOU MIGHT SAY,
"THAT'S SO SAD,

BECAUSE WE WANT TO GET HUMANS
ON THOSE PLANETS."

WELL, ONE, IF YOU REALLY
WANT TO THINK SCIENCE FICTION,

WHY NOT ULTIMATELY
TAKE A MACHINE

THAT CAN BUILD A HUMAN
AT THE OTHER END?

Narrator:
PLANTS SPREAD THEIR GENES

BY SOWING HUGE NUMBERS OF TINY,
MOBILE SEEDS INTO THE WIND.

MANY SEEDS
WILL BE LOST TO THE ELEMENTS,

BUT THOSE THAT FIND WARM,
WET EARTH COME TO LIFE.

IMAGINE FIRING TINY NANO-ROBOTS
INTO SPACE LIKE SEEDS,

WITH HUMAN GENOMES
BURNED ONTO THEIR HARD DRIVES.

IF THEY FALL
THROUGH THE ATMOSPHERE

OF A WET, WARM PLANET
SUITABLE FOR HUMANS,

THEY SPRING INTO ACTION.

THEY'LL LAND AND MAKE SHELTERS

FROM THE MATERIALS
THEY FIND ON THE PLANET.

AND, SOMEHOW,

THEY'LL ALSO MAKE THE HUMANS
THAT LIVE INSIDE THEM.

Kaku:
MAYBE WE'LL SEND THOUSANDS

OF THESE NANOSHIPS,
AS THEY'RE CALLED,

MAYBE MILLIONS OF THEM,
LIKE SEEDS, TO A NEARBY STAR,

HOPING THAT JUST A FEW
OF THEM -- A FEW OF THEM,

ACTUALLY REACH
THEIR DESTINATION.

Narrator: THE TECHNOLOGY
TO CREATE A HUMAN FROM SCRATCH

IS CLEARLY A LONG WAY OFF.

BUT IT DOES RAISE INTRIGUING
PHILOSOPHICAL QUESTIONS.

WHY SHOULD WE ONLY SAVE HUMANS?

THERE ARE 8.7 MILLION SPECIES
ON EARTH.

ARE WE THE ONLY ONES
WORTH SAVING?

AND IF WE CAN'T SEND
THE FULL GAMUT OF LIFE ON EARTH,

WHY NOT SIMPLY SEND BACTERIA
TO DISTANT WORLDS

AND LET EVOLUTION DO THE REST?

AND WHO KNOWS?

MAYBE AN ALIEN SPECIES HAS
ALREADY DONE THAT ON THE EARTH.

MAYBE IN YOUR BACKYARD,

THERE'S A NANOSHIP
FROM A DISTANT STAR SYSTEM,

AND YOU WOULD NEVER KNOW.

Narrator:
WHEREVER WE WIND UP

AND WHATEVER
WE ULTIMATELY BECOME,

THE TIME TO START PLANNING
FOR OUR SURVIVAL IS RIGHT NOW.

Thaller:
THE HUMAN IMAGINATION IS TAKING
US ON SOME TRULY AMAZING PATHS,

AND THEY MAY LEAD US
TO FIND A WAY

WHERE INTERSTELLAR TRAVEL
COULD REALLY WORK.

Plait: OUR FATE IS,
IN MANY WAYS, IN OUR OWN HANDS.

WE'RE NOT DINOSAURS.

WE HAVE A SPACE PROGRAM.
WE'RE SMART.

IF WE HAVE COLONIES
ON OTHER PLANETS,

THE EARTH CAN BE WIPED OUT,
AND HUMANITY WON'T BE.

IN THAT SENSE, OUR FUTURE,
OUR LONG-TERM FUTURE --

THAT'S IN OUR OWN HANDS.