Original subtitles

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.