Original subtitles

♪

Narrator: WE'RE LIVING IN A NEW GOLDEN AGE OF EXPLORATION.

PLANET HUNTERS ARE SEARCHING

FAR BEYOND OUR SOLAR SYSTEM FOR EXOPLANETS.

Woman: WE'RE NOT ONLY FINDING DIFFERENT CONTINENTS --

WE'RE ACTUALLY FINDING NEW WORLDS ORBITING OTHER SUNS.

Narrator: THOUSANDS OF THESE ALIEN WORLDS

HAVE ALREADY BEEN FOUND,

BUT THIS IS THE STORY OF PERHAPS THE GREATEST DISCOVERY YET,

A STAR 40 LIGHT-YEARS AWAY WITH SEVEN EARTH-SIZED PLANETS --

TRAPPIST-1.

WHEN WE SAW THIS, THAT WAS --

IT WAS A VERY HAPPY MORNING WHEN WE MADE THIS PLOT.

REALLY LIKE WINNING THE LOTTERY, SORT OF COSMIC LOTTERY.

Narrator: NOW THESE MODERN-DAY EXPLORERS

ARE RACING TO LEARN MORE ABOUT THESE EXTRAORDINARY WORLDS.

THEY WANT TO KNOW

WHAT THE PLANET'S SURFACES AND CLIMATES ARE LIKE

AND COULD ANY OF THEM WIN THE ULTIMATE BATTLE --

TO HOST LIFE ITSELF?

O'Malley-James: YOU'D SEE THIS PLANET LIGHT UP WITH A GLOW,

THEN THAT GIVES US A STRONG INDICATION

THAT SOMETHING IS LIVING THERE ON THAT PLANET.

Narrator: FINDING LIFE ON AN ALIEN WORLD

IS THE ULTIMATE PRIZE FOR PLANET HUNTERS,

AND IT MAY SOON BE WITHIN REACH.

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

CAPTIONS PAID FOR BY DISCOVERY COMMUNICATIONS

THE STORY BEGINS HIGH IN THE ATACAMA DESERT IN CHILE.

WITH SOME OF THE CLEAREST SKIES ON EARTH,

IT'S ARGUABLY THE BEST PLACE

TO SPOT ALIEN WORLDS ORBITING DISTANT STARS.

AND SURE ENOUGH, THE APTLY NAMED VERY LARGE TELESCOPE

IS HUNTING FOR EXOPLANETS.

IT'S ACTUALLY MADE UP OF FOUR MASSIVE TELESCOPES,

EACH OF WHICH IS ONE OF THE BIGGEST EVER BUILT.

TOGETHER, THEY FORM THE MOST ADVANCED

VISIBLE LIGHT OBSERVATORY IN THE WORLD.

Milli: SO, ALREADY, WITH INDIVIDUAL TELESCOPES,

WE CAN SEE VERY SHARP DETAILS,

BUT WHEN WE COMBINE THE LIGHT OF THE FOUR OF THEM,

WE CAN ACTUALLY DISTINGUISH THE TWO LIGHTS OF A CAR,

OF THE HEADLIGHT OF A CAR, ON THE SURFACE OF THE MOON.

SO THAT'S PRETTY IMPRESSIVE.

Narrator: THE TELESCOPES ARE USED TO STUDY EVERYTHING

FROM NEAR-EARTH ASTEROIDS TO FARAWAY GALAXIES.

DR. JULIEN MILLI IS ONE OF THEIR TOP PLANET HUNTERS.

Milli: WE HAVE HERE THE PRIMARY MIRROR,

SECONDARY MIRROR, TERTIARY MIRROR,

AND THEN IT SENDS THE LIGHT TO HIGH-CONTRAST IMAGERY,

SO THE GOAL IS TO MAKE IMAGES OF PLANETS AROUND THE STAR.

Narrator: WITH FOUR 26-FOOT-WIDE MIRRORS,

THIS IS ONE OF THE ONLY PLACES IN THE WORLD

WHERE ASTRONOMERS CAN ACTUALLY SEE EXOPLANETS.

BUT EVEN IN IDEAL CONDITIONS,

JULIEN AND HIS COLLEAGUE FACE A HUGE CHALLENGE.

PLANET HUNTING CAN BE LIKE FINDING A NEEDLE IN A HAYSTACK

BECAUSE THE IMAGE IS FULL OF OTHER SPOTS

THAT CAN LOOK LIKE PLANETS,

SUCH AS BAD PIXELS AND LIGHT SPECKLES.

♪

Milli: ALL THESE ELONGATED FEATURES

HERE OR IN THE CENTER --

YOU HAVE SOME LITTLE DOTS CLOSE TO THE STAR --

THESE ARE SPECKLES.

SO, THIS IS RESIDUAL STARLIGHT THAT ARE CREATED

BECAUSE OF THE IMPERFECT OPTICS WITHIN THE SYSTEM.

Narrator: THEIR TASK IS TO RULE OUT

ALL THE DOTS THAT ARE BAD PIXELS IN THE HOPE

THAT THEY WILL BE LEFT WITH WHAT'S CALLED A COMPANION,

A REAL PLANET OR OTHER OBJECT ORBITING THE STAR.

♪

TONIGHT, THEY'VE CAPTURED A RARE DIRECT IMAGE

OF AN ALIEN WORLD ORBITING A DISTANT STAR

ALMOST 100 LIGHT-YEARS AWAY.

BUT THIS SO-CALLED "COMPANION" IS NOTHING LIKE EARTH.

IN FACT, IT'S NOT EVEN STRICTLY A PLANET --

IT'S A BROWN DWARF, AN OBJECT SLIGHTLY BIGGER THAN A PLANET.

THIS ONE IS ABOUT 50 JUPITER MASSES.

♪

Milli: WE THINK THAT THE LIGHTEST SUBJECT

THAT WE'RE ABLE TO SEE IS 1 TO 2 JUPITER MASS.

WE CAN'T GO BELOW THAT, UNFORTUNATELY,

SO WE WOULDN'T BE ABLE TO DETECT AN EARTH, FOR INSTANCE.

Narrator: EVEN WITH THE MOST ADVANCED OPTICAL TELESCOPE

EVER BUILT,

VIEWING THESE REMOTE WORLDS DIRECTLY

IS INCREDIBLY CHALLENGING.

AND SEEING EXOPLANETS THE SIZE OF EARTH REMAINS IMPOSSIBLE.

LUCKILY, THERE'S A CLEVER WAY TO FIND EXOPLANETS

WITHOUT EVER ACTUALLY SEEING THEM.

♪

THE MOST SUCCESSFUL PLANET-HUNTING TECHNIQUE SO FAR

HAS BAGGED THOUSANDS OF DISCOVERIES.

BUT AS NASA ASTRONOMER NATASHA BATALHA KNOWS WELL,

YOU NEED PATIENCE.

Batalha: FINDING PLANETS IS A LOT LIKE A STAKEOUT.

YOU'RE SITTING AROUND, WAITING FOR A VERY LONG TIME

BEFORE SOMETHING ACTUALLY HAPPENS.

Narrator: IT CAN TAKE MONTHS OR EVEN YEARS

FOR A PLANET TO ORBIT ITS STAR.

DURING MOST OF THIS TIME,

THEY'RE VIRTUALLY IMPOSSIBLE TO DETECT,

UNLESS THEY HAPPEN TO PASS IN FRONT OF THEIR STAR.

♪

SO, IF YOU CAN IMAGINE A MOTH FLYING IN FRONT

OF A CAR'S HEAD LAMP, THE HEAD LAMP WOULD BE SO BRIGHT

THAT THE MOTH MIGHT BE WASHED OUT,

BUT IF YOU LOOKED HARD ENOUGH,

YOU GET A VERY, VERY SMALL DIP IN BRIGHTNESS,

AND SO WE CAN DETECT THAT BRIGHTNESS,

AND SO THAT'S HOW WE FIND PLANETS.

♪

Narrator: IT'S VERY HARD TO SEE A DISTANT PLANET DIRECTLY,

BUT IF YOU SEE THE LIGHT FROM ITS STAR DIM A LITTLE,

YOU KNOW A PLANET MUST BE PASSING IN FRONT OF IT,

AN EVENT KNOWN AS A TRANSIT.

BUT THIS TRANSIT TECHNIQUE DOESN'T WORK AS WELL

FOR SMALL PLANETS AS BIG ONES.

Batalha: NOW IMAGINE A SMALL FLY IN FRONT OF A CAR'S HEAD LAMP.

THAT FLY WOULD BE SO SMALL

COMPARED TO THE BIG LIGHT OF THE HEAD LAMP

THAT THE DIP IN BRIGHTNESS THAT YOU SEE

IS VERY DIFFICULT TO DETECT.

Narrator: AN EARTH-SIZED PLANET BLOCKS 100 TIMES

LESS LIGHT FROM ITS STAR THAN A JUPITER-SIZED PLANET.

SO, ALTHOUGH HUNDREDS OF GAS GIANTS HAVE BEEN FOUND

THIS WAY, SMALLER WORLDS HAVE PROVED MORE ELUSIVE...

UNTIL ONE ASTRONOMER HAD THE IDEA OF

LOOKING IN A DIFFERENT PLACE -- SMALL RED DWARF STARS.

AND THAT CHANGED EVERYTHING.

♪

RED DWARFS ARE MANY TIMES SMALLER THAN STARS LIKE OUR SUN,

SO EARTH-SIZED PLANETS

WILL CAUSE A BIGGER DIP IN THEIR LIGHT,

ALLOWING ASTRONOMERS TO SPOT SMALL,

ROCKY WORLDS LIKE OUR OWN.

SO, IF YOU'RE LOOKING FOR A TRUE EARTH-LIKE PLANET,

IT'S ACTUALLY EASIER AROUND SMALLER STARS.

♪

Narrator: THIS SIMPLE BUT REVOLUTIONARY APPROACH MEANT

PLANET HUNTERS DIDN'T NEED A GIANT TELESCOPE

TO SEARCH FOR EARTH-SIZED ALIEN WORLDS.

AND JUST 500 MILES SOUTH OF THE VERY LARGE TELESCOPE

SITS A PIONEERING DEVICE THAT'S OVER 10 TIMES SMALLER,

THE BRAINCHILD OF BELGIAN PLANET HUNTER MICHAEL GILLON.

Gillon: MY GOAL WAS TO DETECT NEW PLANETS,

WITH A SPECIAL FOCUS ON SMALL PLANETS

THAT WOULD BE POTENTIALLY HABITABLE,

SO THAT COULD HAVE ALL LIQUID WATER ON THE SURFACE,

POSSIBLY, MAYBE LIFE -- WHO KNOWS?

Narrator: TO SEARCH FOR THESE NEW WORLDS,

MICHAEL BEGAN STALKING OUT RED DWARF STARS IN 2011,

USING HIS SMALL TELESCOPE,

WHICH HE NAMED "TRAPPIST," AFTER THE BEER,

WHICH IS FAMOUSLY BREWED BY HAND IN BELGIUM.

BUT UNLIKE TRAPPIST BEER,

THIS ROBOTIC TELESCOPE CAN BE OPERATED

FROM ANYWHERE IN THE WORLD WITH AN INTERNET CONNECTION.

Gillon: THE TELESCOPE ITSELF IS A REMOTE-CONTROLLED DEVICE,

SO WE JUST PRESS A BUTTON AND LAUNCH A TELESCOPE,

AND IT STARTS OBSERVING.

AND DURING THE WHOLE NIGHT, IT WILL OBSERVE

WITHOUT ANY HUMAN INTERVENTION.

Narrator: FOR FOUR YEARS, THE TRAPPIST TELESCOPE

STEADILY RECORDED THE BRIGHTNESS OF INDIVIDUAL STARS,

ONE BY ONE,

WAITING FOR THE CHARACTERISTIC DIP THAT REVEALS A PLANET,

AND IT WAS REMARKABLY SUCCESSFUL.

SO, IN 2015, WE HAD AROUND 100 GIANT EXOPLANETS

THAT WE CONTRIBUTED TO THE DISCOVERY.

AND SO IT WAS VERY ENCOURAGING,

BUT, OF COURSE, THE DREAM WAS STILL EARTH-SIZED PLANETS.

Narrator: THE TRAPPIST TELESCOPE WAS WORKING PERFECTLY,

BUT 7,000 MILES AWAY,

MICHAEL WAS STILL HOPING FOR AN HISTORIC BREAKTHROUGH.

THEN, ON SEPTEMBER 16, 2015,

A DRAMATIC SEQUENCE OF EVENTS ENDED IN A HUGE DISCOVERY.

♪

♪

Narrator: ON SEPTEMBER 16, 2015,

TRAPPIST WAS SCHEDULED TO WATCH A VERY FAINT RED DWARF STAR

JUST 40 LIGHT-YEARS AWAY, BUT THAT NIGHT,

A POWERFUL EARTHQUAKE STRUCK NORTHERN CHILE.

THE TRAPPIST TELESCOPE

WAS IN ONE OF THE WORST AFFECTED AREAS,

BUT IT WAS BUILT TO WITHSTAND SEISMIC EVENTS.

Hibon: WHEN THERE IS A CERTAIN LEVEL OF EARTHQUAKE,

THE FIRST THING THAT HAPPENS

IS THAT THE TELESCOPE IS GOING TO STOP FUNCTIONING.

Gillon: THE OBSERVATION STOPPED,

AND THE DOME WAS CLOSED IN SAFE MODE.

AND THEN, IN THE MORNING,

MY STUDENT NOTICED THE SITUATION,

AND SHE RELAUNCHED THE OBSERVATION OF THE STAR.

Narrator: THE TELESCOPE WASN'T DAMAGED,

BUT BY THE TIME IT WAS WORKING AGAIN,

THE NIGHT WAS NEARLY OVER AND THERE WERE ONLY THREE HOURS

LEFT TO OBSERVE THE TARGET STAR BEFORE DAWN.

BACK IN EUROPE, MICHAEL WAS ANALYZING THE DATA

WHEN SOMETHING CAUGHT HIS EYE.

Gillon: I WAS AT HOME ON MY SOFA WITH MY LAPTOP,

AND I SAW A VERY CLEAR TRANSITLIKE SIGNAL,

AND SO I WAS SUPER, SUPER EXCITED, AND FURTHERMORE,

I KNEW THAT THE STAR WAS SMALL.

SO THE PLANET SHOULD HAVE BEEN

MORE OR LESS THE SIZE OF THE EARTH.

Narrator: 40 LIGHT-YEARS AWAY, AN EARTH-SIZED PLANET

HAD PASSED IN FRONT OF ITS DWARF STAR,

AND THE EARTHQUAKE ALMOST CAUSED MICHAEL AND HIS TEAM TO MISS IT.

♪

THE TRAPPIST TELESCOPE HAD MADE ITS FIRST DISCOVERY

OF AN EARTH-SIZED PLANET -- A HUGE ACHIEVEMENT.

♪

THE SYSTEM WAS NAMED TRAPPIST-1 IN ITS HONOR,

BUT AS THEY CONTINUED TO WATCH, IT SOON BECAME CLEAR

THAT THIS WAS NOT THE REGULAR SIGNAL

YOU'D EXPECT FROM A SINGLE PLANET.

Gillon: ONE PLANET SHOULD LEAD

TO ONE FREQUENCY, ONE PRIORITY --

IT SHOULD BE SOMETHING LIKE DEET-DEET-DEET-DEET.

YOU LOOKED AT THE DATA, AND IT'S DEE-DEET,

DEE-DEE-DEE-DEET, DEE-DEET, DEE-DEE-DEE-DEE-DEET,

DEE-DEET -- SOMETHING LIKE THIS, SO IT'S TOTALLY DIFFERENT.

Narrator: THAT COULD MEAN ONLY ONE THING -- MORE PLANETS.

BUT TO FIND OUT HOW MANY,

MICHAEL NEEDED MORE OBSERVATIONS.

OBSERVATORIES ALL OVER THE WORLD,

INCLUDING THE VERY LARGE TELESCOPE,

SWUNG THEIR GAZE TOWARD THE TRAPPIST-1 STAR,

AND THE RESULTS WERE GROUNDBREAKING.

Gillon: AND WE OBSERVED PLENTY, PLENTY OF NIGHTS WITH

PLENTY, PLENTY OF TRANSIT, AND AT SOME POINT,

WE ARE SURE THERE WERE FOUR PLANETS AND FIVE PLANETS,

THEN MAYBE SIX, MAYBE SEVEN.

IN FACT, IT WAS REALLY TOO COMPLEX FOR US TO DECIPHER

BECAUSE WE WERE OBSERVING FROM THE GROUND, FROM EARTH,

AND WE KNEW WE NEEDED VERY PRECISE OBSERVATION

AND CONTINUOUS OBSERVATION.

♪

Narrator: THE ONLY WAY TO GET A CLEAR ENOUGH PICTURE

OF THE RED DWARF STAR WOULD BE TO VIEW IT FROM SPACE.

♪

TELESCOPES BEYOND EARTH ARE FEW AND FAR BETWEEN,

SO TIME ON THEM IS LIMITED.

BUT AS NEWS SPREAD OF THIS EXTRAORDINARY DISCOVERY,

EVERY RESOURCE WAS SOON PUT AT THEIR DISPOSAL,

INCLUDING ONE OF NASA's FOUR GREAT OBSERVATORIES,

THE SPITZER SPACE TELESCOPE.

ASTRONOMER SEAN CAREY RUNS

NASA's SPITZER SCIENCE CENTER IN CALIFORNIA.

♪

SO, THIS IS A MODEL OF THE SPITZER SPACE TELESCOPE.

IT'S A 1/3 SCALE MODEL,

SO ADD TWO MORE OF THESE ON TOP --

THEN YOU GET A SENSE OF HOW BIG THE TELESCOPE IS IN SPACE.

Narrator: SPITZER WAS THE PERFECT INSTRUMENT

TO GATHER MORE INFORMATION ABOUT TRAPPIST-1.

FIRST, IT'S AN INFRARED TELESCOPE,

SO THE TRAPPIST-1 STAR IS 4,000 TIMES BRIGHTER IN THE INFRARED

THAN IT IS IN VISIBLE LIGHT.

THE SECOND THING IS SPITZER'S ORBIT,

BECAUSE SPITZER ISN'T ON THE EARTH,

SO IT DOESN'T HAVE DAY/NIGHT.

YOU KNOW, WE DON'T HAVE TO STOP OBSERVING WHEN THE SUN COMES UP,

AND THAT ALLOWS US TO LOOK AT OBJECTS FOR A MUCH LONGER TIME.

Narrator: THE SPACE TELESCOPE WATCHED THE TRAPPIST STAR

FOR OVER 20 CONTINUOUS DAYS AND NIGHTS.

Carey: SO, THESE ARE IMAGES FROM SPITZER OF TRAPPIST-1,

AND BELIEVE IT OR NOT, WHAT YOU'RE LOOKING AT

ARE THE DATA THAT WERE USED TO DETERMINE

THE NUMBER OF PLANETS AROUND TRAPPIST-1

AND HELP US TO DETERMINE THEIR PROPERTIES.

AND SO, IF YOU MEASURE THE AMOUNT OF WHITE FROM THE STAR

AND THEN PLOT THAT AS A FUNCTION OF TIME --

THIS IS WHAT ASTRONOMERS DO -- YOU SEE THESE DIPS,

BECAUSE THAT'S WHEN A PLANET PASSES IN FRONT OF THE STAR.

WHEN WE SAW THIS, THAT WAS --

IT WAS A VERY HAPPY MORNING WHEN WE MADE THIS PLOT.

Narrator: SCIENTISTS AROUND THE WORLD

RACED TO DECIPHER THE SIGNAL.

WE ANALYZED THE DATA AS SOON AS THEY CAME FROM SPACE,

AND THE CONCLUSION THAT THERE WERE SEVEN PLANETS

WAS INESCAPABLE.

MY BEST HOPE WOULD HAVE BEEN TO DETECT ONE PLANET,

SO THIS SYSTEM OF SEVEN PLANETS

CAME OUT THE BLUE TO OUR SURPRISE,

AND REALLY LIKE WINNING THE LOTTERY, SORT OF COSMIC LOTTERY.

♪

Narrator: PLANET HUNTER EXTRAORDINAIRE MICHAEL GILLON

HAD MADE AN HISTORIC DISCOVERY,

ARMED WITH A REMARKABLY SMALL TELESCOPE.

BUT THIS WAS JUST THE BEGINNING OF THE STORY.

♪

♪

Narrator: SINCE THE HISTORIC DISCOVERY

OF THE SEVEN EARTH-SIZED PLANETS THAT SURROUND THE TRAPPIST STAR,

SCIENTISTS HAVE BEEN PIECING TOGETHER THE DATA,

LEARNING MORE ABOUT THESE ALIEN WORLDS,

AND GIVING A GLIMPSE OF HOW THEY MIGHT LOOK

FROM A NEIGHBORING PLANET.

Gillon: THE SYSTEM IS UNIQUE,

NOT ONLY BY THE SHEER NUMBER OF EARTH-SIZED PLANETS,

BUT ALSO BECAUSE OF ITS VERY COMPACT CONFIGURATION --

THE PLANETS ARE VERY CLOSE TO EACH OTHER.

SO YOU CAN IMAGINE THE VIEWS YOU SHOULD HAVE

FROM THE SURFACE OF ONE OF THESE PLANETS --

YOU WOULD SEE THE OTHER PLANETS LIKE WE SEE THE MOON.

SO YOU WOULD SEE ALL THE DETAILS,

NOT JUST A DOT OF LIGHT,

BUT YOU WOULD REALLY SEE -- I DON'T KNOW --

THE CLOUDS, THE CONTINENTS, WHATEVER IS THERE.

Narrator: AS WELL AS THE PLANETS BEING NEAR EACH OTHER,

THEY ARE ALSO MUCH CLOSER TO THEIR STAR,

KNOWN AS TRAPPIST-1a.

THE INNER TWO PLANETS,

TRAPPIST-1b AND 1c, ARE IN A DANGER ZONE,

OVER 60 TIMES CLOSER TO THE RED DWARF STAR

THAN THE EARTH IS TO THE SUN.

♪

Loeb: FROM THE SURFACE OF ITS NEAREST PLANET,

TRAPPIST-1 WOULD APPEAR 10 TIMES BIGGER

THAN THE SUN LOOKS TO US HERE ON EARTH.

IT WOULD BE RED AND HEATING THE SURFACE TO A TEMPERATURE

THAT IS WELL ABOVE THE BOILING TEMPERATURE OF WATER,

SO IT WOULD BE EXTREMELY HOT ON A SUNNY DAY OUT THERE.

Narrator: HARVARD PROFESSOR AVI LOEB HAS STUDIED

HOW STARS CAN AFFECT NEARBY PLANETS.

THE INNER TWO TRAPPIST WORLDS ARE SO CLOSE TO THE RED DWARF

THAT ONE SIDE OF EACH PLANET

IS THOUGHT TO BE GRAVITATIONALLY LOCKED TO ALWAYS FACE ITS SUN,

MEANING ONE HEMISPHERE WOULD BE CONTINUOUSLY BLASTED

BY INTENSE RADIATION,

WHILE THE OTHER IS TRAPPED IN PERPETUAL DARKNESS.

ONE SIDE OF THE PLANET THAT IS FACING THE STAR WOULD BE SO HOT

THAT LIQUID WATER WOULD BOIL OFF THE SURFACE.

THE OTHER SIDE WOULD BE EXTREMELY COLD, SUCH THAT

IF THERE IS ANY WATER THERE, IT WOULD BECOME ICE.

IN BETWEEN THE TWO REGIONS,

THERE IS A PERMANENT SUNSET STRIP

FROM WHICH ONE CAN ALWAYS SEE THE SUNSET.

♪

Narrator: THE AVERAGE TEMPERATURE

ON PLANET TRAPPIST-1b

COULD BE AROUND 270 DEGREES FAHRENHEIT,

BUT ON THE DAY SIDE,

IT COULD GET MUCH HOTTER THAN THAT.

THE EXTREME HEAT FROM THE STAR

MIGHT EVEN CREATE A THICK HAZE COVERING THE SURFACE.

♪

BUT AS WELL AS SCORCHING THE INNER PLANETS FROM ABOVE,

THE RED DWARF STAR ALSO GENERATES

INCREDIBLY POWERFUL MAGNETIC FIELDS.

DR. KRISTINA KISLYAKOVA HAS STUDIED HOW THIS INVISIBLE FORCE

CAN ACTUALLY CAUSE THE PLANETS CLOSEST TO THE STAR

TO HEAT UP FROM THE INSIDE.

SHE'S COME TO A FOUNDRY THAT MELTS STEEL INSIDE FURNACES

BY GENERATING A POWERFUL MAGNETIC FIELD.

Kislyakova: SO, HERE, WE ARE LOOKING AT

A FEW INDUCTION FURNACES,

WHICH ARE USED TO MELT MATERIALS,

ESPECIALLY METAL, USING INDUCTION-HEATING EFFECT,

AND THE SAME VERY EFFECT CAN BE AT WORK

IN THE TRAPPIST-1 PLANETARY SYSTEM.

Narrator: THE MAGNETIC FIELD CHANGES DIRECTION

200 TIMES EVERY SECOND,

TRIGGERING INTENSE ELECTRICAL CURRENTS DEEP INSIDE THE METAL.

AS ELECTRONS SWARM THROUGH THE STEEL,

THEY CRASH INTO ITS ATOMS,

HEATING IT TO OVER 2,500 DEGREES FAHRENHEIT.

♪

AS THE PLANETS HURTLE 'ROUND THE STAR,

THEY PASS THROUGH A RAPIDLY CHANGING MAGNETIC FIELD,

WHICH HEATS METALS DEEP WITHIN THEM.

♪

THIS PHENOMENON IS FAR MORE POWERFUL

THAN IT IS IN OUR OWN SOLAR SYSTEM

BECAUSE THE TRAPPIST-1 STAR HAS A MAGNETIC FIELD

HUNDREDS OF TIMES STRONGER THAN OUR SUN,

AND ITS PLANETS ARE MUCH NEARER.

THE CLOSER YOU GO TO THE STAR, THE STRONGER THE EFFECT WILL BE,

SIMPLY BECAUSE THE MAGNETIC FIELD

WILL BE STRONGER CLOSER TO THE STAR.

SO, IN TRAPPIST-1 SYSTEM PLANETS,

b AND c HAVE THE MOST SIGNIFICANT EFFECT.

IF THE MAGNETIC FIELD IS STRONG ENOUGH,

IT WILL BASICALLY CREATE CURRENTS OF SUCH STRENGTH

THAT IT WILL MELT THE PLANETARY MANTLE.

♪

Narrator: KRISTINA'S STUDY PREDICTS THAT MOLTEN ROCK

COULD BE FLOWING UNDER THE SURFACE OF THE INNER PLANETS,

AND JUST LIKE ON EARTH,

WHEN PLANETS HAVE MOLTEN ROCK INSIDE,

IT WILL SOMETIMES FORCE ITS WAY TO THE SURFACE,

CREATING VOLCANOES.

♪

THE CLOSEST WORLDS TO THE STAR COULD BE COVERED IN VOLCANOES

ALL OVER THEIR SURFACE.

MAYBE ONE CAN IMAGINE THAT IT KIND OF LOOKS SOMETHING SIMILAR

TO THIS FURNACE, WHERE ONE CAN SEE

THE MOLTEN METAL WITH FUMES COMING OUT OF IT.

♪

Narrator: ALTHOUGH NOT AS VOLCANIC

AS THE INNERMOST PLANET,

TRAPPIST-1c IS LESS LIKELY TO BE SHROUDED IN A HOT, GASSY HAZE,

REVEALING A POCKMARKED, DESOLATE SURFACE.

IT MAY LOOK LIKE A MUCH HOTTER VERSION

OF THE MOST VOLCANIC BODY IN OUR OWN SOLAR SYSTEM,

JUPITER'S MOON IO.

♪

BEYOND THE FIERY DANGER ZONE,

THE NEXT TWO PLANETS ARE IN A COOLER, MORE TEMPERATE ZONE.

IN FACT, SCIENTISTS HAVE CALCULATED THAT TRAPPIST-1d

AND 1e GET A SIMILAR AMOUNT OF HEAT FROM THEIR STAR

AS THE EARTH DOES FROM THE SUN.

BUT TO FIND OUT HOW SIMILAR THEY REALLY ARE TO OUR WORLD,

SCIENTISTS ARE STRIVING TO DISCOVER MORE

ABOUT THESE PLANETS,

AND THEY'RE MAKING GOOD PROGRESS.

♪

♪

Narrator: AT NASA's SPITZER SCIENCE CENTER,

ASTRONOMER SEAN CAREY IS PART OF A TEAM OF SCIENTISTS

MAKING GREAT STRIDES IN THE RACE TO FIND OUT MORE ABOUT

THE EXTRAORDINARY WORLDS OF TRAPPIST-1.

WE KNOW AN AMAZING AMOUNT ABOUT THE TRAPPIST-1 PLANETS,

COMPARED TO OTHER EXOPLANETS.

IN FACT, WE KNOW MORE ABOUT THIS PARTICULAR SYSTEM

THAN ANY OTHER PLANETARY SYSTEM EXCEPT FOR OUR OWN SOLAR SYSTEM.

Narrator: SCIENTISTS WERE ABLE TO WORK OUT THE MASS

AND SIZE OF EACH PLANET FROM THE SPITZER DATA

AND COULD THEN USE THESE RESULTS TO CALCULATE HOW DENSE THEY ARE.

LIKE ALL KINDS OF ROCKS,

SOME ARE MUCH DENSER THAN OTHERS.

♪

SO, HERE ARE A SELECTION OF METEORITES.

MOST OF THESE ARE FROM ASTEROIDS IN OUR SOLAR SYSTEM,

AND THIS ONE HERE IS FROM MARS.

THIS ONE HERE IS VERY DARK.

IT'S RATHER HEAVY.

IT'S MADE MOSTLY OF IRON.

THIS ONE IS MUCH ROCKIER.

IT'S A MIXTURE OF IRON ROCK, BUT MORE ROCK THAN IRON.

IT'S MUCH LIGHTER THAN AND MUCH LESS DENSE THAN THIS.

Narrator: AS WITH METEORITES, THE DENSITY OF A PLANET

CAN GIVE YOU A CLUE AS TO WHAT IT'S MADE OF,

AND THE MOST TANTALIZING SUBSTANCES

TO FIND ON THE TRAPPIST WORLD WOULD BE THE LEAST DENSE,

LIKE WATER AND A GASSY ATMOSPHERE.

♪

WHEN THE DENSITY OF THE PLANETS WAS FINALLY CALCULATED,

THE TEAM GAINED A FASCINATING GLIMPSE

OF WHAT THESE WORLDS MIGHT BE LIKE.

THE DENSITIES TELL US THAT THEY'RE LIGHTER

THAN A PURE BALL OF ROCK, THAT THERE HAS TO BE

LIGHTER MATERIAL, LIKE WATER OR LIKE CARBON DIOXIDE.

TRAPPIST-1d AND e, WHICH HAVE TEMPERATURES

WHICH ARE KIND OF SIMILAR TO THE EARTH,

WOULD POTENTIALLY HAVE LIQUIDS ON THEIR SURFACE,

POTENTIALLY LIQUID WATER.

BUT, THEN, YOU KNOW, IF YOU START TALKING ABOUT WATER,

YOU CAN TALK ABOUT THE POTENTIAL FOR LIFE,

SO EVERYBODY'S EXCITED ABOUT THAT.

Narrator: SCIENTISTS THINK BOTH THE TRAPPIST PLANETS

IN THE TEMPERATE ZONE HAVE WATER ON THEM.

TRAPPIST-1d IS ACTUALLY THE LEAST DENSE OF ALL THE PLANETS,

WHICH MEANS IT COULD HAVE 250 TIMES MORE WATER THAN EARTH.

WITH A WARM CLIMATE, IT COULD BE A WATER WORLD,

COVERED BY A DEEP OCEAN OVER THE ENTIRE SURFACE.

♪

THE FOURTH PLANET, HOWEVER, TRAPPIST-1e,

HAS ALMOST THE SAME DENSITY AS EARTH,

SUGGESTING IT COULD HAVE A MIX OF OCEANS AND LAND,

WHICH WOULD MAKE IT LOOK EERILY LIKE OUR HOME.

♪

BEYOND THIS TEMPERATE ZONE,

THE LAST THREE PLANETS RECEIVE MUCH LESS HEAT FROM THEIR STAR.

IN ITS FRIGID ZONE, THESE OUTERMOST WORLDS

ALSO HAVE A LOW ENOUGH DENSITY TO HAVE WATER IN SOME FORM.

TO FIND OUT IF THEY'RE ALL JUST FROZEN ICE BALLS,

SCIENTISTS NEED TO KNOW ANOTHER CRUCIAL DETAIL.

DR. ALEXANDRIA JOHNSON CREATES ALIEN SKIES IN HER LAB.

Johnson: WE'RE TRYING TO SIMULATE

EXOPLANET ATMOSPHERES --

IN PARTICULAR, WE'RE TRYING TO LOOK AT

HOW EXOPLANET CLOUDS SCATTER LIGHT,

'CAUSE IT TELLS US A LITTLE BIT ABOUT THE ATMOSPHERE

AND THE CLIMATE ON THAT SYSTEM.

Narrator: BY FIRING A LASER AT CLOUD PARTICLES IN A CHAMBER,

ALEXANDRIA CAN SEE IF THE LIGHT GETS ABSORBED BY THE ATMOSPHERE

OR REFLECTED BACK OUT TO SPACE.

SHE CAN THEN MULTIPLY THE EFFECT BY THE MILLIONS OF PARTICLES

IN A CLOUD TO SIMULATE THE OVERALL IMPACT ON AN EXOPLANET.

Johnson: SO, WE DON'T QUITE KNOW IF THERE ARE CLOUDS

ON THE TRAPPIST PLANETS YET,

BUT IF WE STUDY THEM IN THIS MANNER,

WE CAN GET AN IDEA OF HOW MUCH STARLIGHT

IS ACTUALLY MAKING IT INTO THE ATMOSPHERE,

AND THUS, HOW WARM THE ATMOSPHERES COULD BE

AND WHAT SORT OF CLIMATES MIGHT BE ON THESE PLANETS.

Narrator: THE CLOUDS AROUND A PLANET CAN CHANGE ITS CLIMATE,

AND SO CAN THE GASES IN ITS ATMOSPHERE.

TO STUDY THAT, THERE'S NO BETTER LAB THAN THE EARTH ITSELF.

FORTUNATELY, ALEXANDRIA'S LAB

IS IN THE TALLEST BUILDING IN CAMBRIDGE, MASSACHUSETTS,

THE PERFECT SPOT FOR A WEATHER STATION.

SO, IN BOSTON, IN MASSACHUSETTS, WE'VE BEEN RECORDING

THE TEMPERATURE SINCE THE EARLY 1900s,

AND WHAT WE'VE SEEN IS THAT OVER THE 20th CENTURY,

THERE'S AN AVERAGE TEMPERATURE.

BUT OVER THE PAST 25 YEARS,

THE AVERAGE TEMPERATURE FOR THE YEAR

HAS ALWAYS BEEN HIGHER THAN THAT.

SO WHAT WE'RE SEEING IS CONTINUAL WARMING

OF THE ATMOSPHERE.

IT'S PRETTY MUCH THE SAME TREND WE SEE ALL OVER THE WORLD.

♪

Narrator: IT'S NOW WELL-KNOWN THIS WARMING

IS CAUSED BY MORE GREENHOUSE GASES IN THE ATMOSPHERE.

Johnson: THE MAIN ONES ARE CARBON DIOXIDE AND METHANE,

AND THEY COLLECT THE INFRARED RADIATION

THAT'S GIVEN OFF BY THE SURFACE,

AND THEN, THEY, IN TURN, HEAT THE ATMOSPHERE.

Narrator: JUST LIKE ON EARTH,

THESE GASES CAN TRAP HEAT ON EXOPLANETS.

ASTRONOMERS HAVE CALCULATED THAT WITHOUT AN ATMOSPHERE,

THE OUTER TRAPPIST PLANETS WOULD BE FROZEN SOLID,

BUT WITH THE RIGHT KIND OF ATMOSPHERE AND CLOUDS,

THESE GIANT SNOWBALLS COULD WARM UP.

IF YOU PUT INTO A SYSTEM THESE GREENHOUSE GASES,

CREATE A SUBSTANTIAL ATMOSPHERE,

YOU CAN BEGIN TO TRAP THE RADIATION FROM THAT STAR,

THEN YOU CAN HAVE WARMING, AND YOU COULD ACTUALLY,

POTENTIALLY, HAVE LIQUID AT THE SURFACE.

♪

Narrator: WITH HELP FROM AN ATMOSPHERE,

CALCULATIONS SHOW THAT PLANET TRAPPIST-1f RECEIVES

JUST ENOUGH HEAT TO MELT WATER AT ITS WARMEST REGION,

AN ICE-RIMMED OCEAN FORMING THE PUPIL OF A FROZEN EYEBALL

STARING AT ITS SUN.

BUT THE LAST TWO PLANETS

HAVE LESS HOPE OF LIQUID WATER ON THEIR SURFACE.

Johnson: TRAPPIST PLANETS 1g AND 1h ARE FURTHER FROM THEIR STAR,

SO THEY RECEIVE LESS RADIATION,

WHICH MEANS IT'S ACTUALLY CONSIDERED TO BE PAST

THE ICE LINE, WHICH IS A TEMPERATURE REGIME

WHERE THE VOLATILE, SUCH AS WATER,

WOULD BE LOCKED UP IN SOLIDS, LIKE ICE.

Narrator: PLANET TRAPPIST-1g RECEIVES SO LITTLE HEAT

FROM THE STAR THAT EVEN WITH AN ATMOSPHERE,

ITS SURFACE IS LIKELY COVERED IN SOLID ICE.

WITHOUT ONE, IT COULD BE AS BITTERLY COLD

AS NIGHT ON MARS -- MINUS 112 DEGREES FAHRENHEIT.

FINALLY, THE FRIGID OUTERMOST WORLD OF THE TRAPPIST-1 SYSTEM

IS THE COLDEST OF ALL.

WITH A SURFACE TEMPERATURE PREDICTED TO BE NO MORE

THAN 150 DEGREES BELOW FREEZING,

IT COULD BE ALMOST AS COLD AS JUPITER'S LARGEST MOON,

ICY GANYMEDE.

♪

THE UNREMARKABLE TRAPPIST-1 STAR HAS SEVEN EXTRAORDINARY WORLDS,

OF WHICH AT LEAST THREE MAY HAVE THICK ATMOSPHERES

AND LIQUID WATER ON THEIR SURFACES,

FEATURES THAT WOULD MAKE THE PLANETS POTENTIALLY HABITABLE.

AND THAT RAISES AN ENTICING QUESTION --

COULD THESE WORLDS ALSO HARBOR LIFE?

♪

♪

Narrator: AS SCIENTISTS LEARN MORE

ABOUT THE EXTRAORDINARY WORLDS

THAT SURROUND THE TRAPPIST-1 STAR,

THEY'RE FINDING THAT AT LEAST THREE OF THEM

HAVE THE POTENTIAL FOR LIFE, BUT THERE'S A PROBLEM.

TO GIVE EVOLUTION ENOUGH TIME TO GET STARTED,

YOU ALSO NEED STABILITY...

♪

...SOMETHING THE TRAPPIST PLANETS, AT FIRST, SEEM TO LACK.

♪

FROM PLANET TRAPPIST-1h,

THE OTHER SIX WORLDS WOULD HANG CLEARLY IN THE SKY,

A STUNNING DISPLAY OF JUST HOW COMPACT THE SYSTEM IS.

BUT IF PLANETS GET TOO NEAR EACH OTHER, IT CAN SPELL DOOM.

Russo: THE PLANETS ARE ALL VERY CLOSE TOGETHER,

AND SO, THEY EACH FEEL EACH OTHER'S GRAVITY

AND THEY GIVE EACH OTHER LITTLE TUGS OVER AND OVER AGAIN,

AND THAT CAN BE A VERY DANGEROUS SITUATION.

Narrator: WHEN HE HEARD ABOUT THE COMPACT SYSTEM,

ASTROPHYSICIST MATT RUSSO WAS FASCINATED BY THESE INTERACTIONS

AND THE FATE OF THE PLANETS.

WHEN THE TRAPPIST-1 PLANETS WERE FIRST DISCOVERED,

ASTRONOMERS TRIED TO SIMULATE THEIR ORBITS,

AND THEY FOUND THAT AFTER A VERY SHORT AMOUNT OF TIME,

THE SYSTEM WENT UNSTABLE --

PLANETS STARTED CRASHING INTO EACH OTHER OR GETTING EJECTED.

IT WAS JUST A COMPLETE MESS VERY, VERY FAST.

SO, THAT MEANS THAT EITHER WE'RE CATCHING THE SYSTEM

JUST BEFORE EVERYTHING GOES HAYWIRE

OR THERE IS SOMETHING MYSTERIOUS KEEPING THIS SYSTEM STABLE.

Narrator: THE SEVEN WORLDS APPEAR

ON THE VERGE OF CATASTROPHE,

BUT APPEARANCES CAN BE DECEPTIVE.

AS WELL AS BEING A SCIENTIST,

MATT IS AN ACCOMPLISHED MUSICIAN,

AND THIS TRAPPIST MYSTERY

GOT HIM THINKING ABOUT AN UNUSUAL CONNECTION.

♪

WITH THE HELP OF AN ORCHESTRA, HE SET OUT TO TRANSLATE

THE MOVEMENTS OF THE PLANETS INTO ACTUAL MUSIC.

Russo: IF YOU SPEED UP THE MOTION OF THESE PLANETS

BY MILLIONS OF TIMES,

THEIR MOTION WOULD ACTUALLY PRODUCE MUSICAL NOTES.

Narrator: IF THE ORCHESTRA REPRESENTS THE TRAPPIST SYSTEM,

THEN TUNING UP IS A BIT LIKE HOW THE PLANETS FORMED,

AND THAT COULD BE THE KEY TO THE SYSTEM'S SURVIVAL.

SO, WHEN PLANETS FORM,

THE PLANETS ARE ORBITING INSIDE A DISC OF GAS AND DUST,

AND WHILE THEY'RE INSIDE THAT DISC,

THEY CAN SLIDE AROUND AND TUNE THEMSELVES TO THEIR NEIGHBORS.

AND AS THESE PLANETS SLIDE AROUND, SOMETIMES,

THEY CAN GET LOCKED INTO A VERY STABLE CONFIGURATION.

♪

Narrator: THE DIFFERENT SECTIONS OF THE ORCHESTRA ARE NOW

IN HARMONY WITH EACH OTHER, PLAYING THE MUSIC

OF THE PERFECTLY SYNCHRONIZED TRAPPIST-1 SYSTEM.

♪

THE UNPRECEDENTED SYMMETRY THAT ALLOWS MATT

TO TURN THE TRAPPIST-1 ORBITS INTO MUSIC

ALSO CAUSES ALL THE PLANETARY TUGS

TO CANCEL EACH OTHER OUT, KEEPING THE PLANETS IN BALANCE.

♪

WE NOW KNOW THAT THE TRAPPIST-1 SYSTEM

IS ABOUT 7 BILLION YEARS OLD --

THAT'S MUCH OLDER THAN OUR OWN SOLAR SYSTEM.

AND SO, IF THESE PLANETS WEREN'T FINELY TUNED

IN THIS MUSICAL CONFIGURATION,

THERE'S NO WAY THEY COULD HAVE LASTED THAT LONG.

Narrator: IF IT TURNS OUT THAT ANY OF THE TRAPPIST-1 PLANETS

DO HAVE THE RIGHT CONDITIONS FOR LIFE, 7 BILLION YEARS

IS CERTAINLY LONG ENOUGH FOR EVOLUTION TO GET GOING --

AN EXHILARATING POSSIBILITY.

♪

BUT NOT EVERYONE IS OPTIMISTIC.

LIKE OUR SUN, THE TRAPPIST STAR PRODUCES EXPLOSIVE,

DESTRUCTIVE OUTBURSTS CALLED "STELLAR FLARES."

♪

THE BIGGEST SOLAR FLARES OF OUR SUN

CAN RELEASE THE ENERGY OF A BILLION HYDROGEN BOMBS.

YET, THE SUN'S ACTIVITY IS RELATIVELY TAME

COMPARED TO THAT OF OTHER STARS, INCLUDING RED DWARFS,

LIKE TRAPPIST-1, THAT ARE MUCH SMALLER IN SIZE.

THESE STARS ARE FAINTER THAN THE SUN BY 10,000 TIMES,

BUT THE FREQUENCY OF FLARES ON RED DWARFS IS MUCH HIGHER,

AND THE FLARES ARE MUCH MORE POWERFUL

THAN THEY ARE FOR THE SUN.

♪

Narrator: WHENEVER THE TRAPPIST STAR FLARES,

THE NEARBY PLANETS ARE BATHED IN INTENSE ULTRAVIOLET,

OR UV, LIGHT, AND THIS KIND OF RADIATION

CAN HAVE A DEVASTATING EFFECT ON LIFE.

♪

WITH THE TRAPPIST PLANETS SO CLOSE

TO SUCH A VOLATILE STAR,

AVI LOEB DOUBTS WHETHER LIVING ORGANISMS COULD SURVIVE.

Loeb: I BELIEVE THAT THE PLANETS AROUND TRAPPIST-1

DO NOT HAVE LIFE AS WE KNOW IT ON THEM DUE TO THE MANY RISKS

THAT THIS ENVIRONMENT POSES FOR LIFE.

Narrator: YET, OTHER SCIENTISTS BELIEVE

THERE MAY BE REASON FOR HOPE.

♪

ASTROBIOLOGIST JACK O'MALLEY-JAMES

WANTS TO KNOW IF THERE'S A WAY FOR LIFE

TO SURVIVE THESE STELLAR SUPERFLARES.

TO FIND OUT, HE'S BEEN INVESTIGATING HOW LIFE ON EARTH

COPES WITH UV.

HE'S COME TO THE LONDON AQUARIUM

TO SEE HOW SEA CREATURES RESPOND TO THE RADIATION.

SO, MOST OF THE SUN'S UV IS FILTERED OUT

BY THE OZONE LAYER IN THE ATMOSPHERE,

AND THE REST THAT MAKES IT DOWN TO THE SURFACE IS LOW ENOUGH

THAT ANIMALS CAN COPE WITH IT BY MOVING AWAY INTO THE SHADE,

LIKE THIS SEA TURTLE HERE, WHICH IS HIDING UNDER A ROCK --

ANYTHING THAT PUTS A SMALL BARRIER BETWEEN YOU

AND THAT RADIATION IS ENOUGH.

Narrator: BUT NOT ALL CREATURES CAN ESCAPE INTO THE SHADE

DURING THE HEAT OF A MIDDAY SUN.

CORAL POLYPS ARE SMALL ANIMALS

THAT CREATE HARD SKELETONS AROUND THEIR BODIES,

WHICH, TOGETHER, ANCHOR CORAL REEFS TO THE SEAFLOOR.

CORALS, LIKE IN THIS REEF HERE, ARE STUCK IN PLACE.

SO, WHEN THEY'RE EXPOSED TO HIGH LEVELS OF UV RADIATION,

SUCH AS WHEN THE TIDE GOES OUT,

THEY CAN'T MOVE AWAY FROM IT, THEY CAN'T HIDE,

AND SO THEY NEED TO DO SOMETHING ELSE

TO DEAL WITH THAT RADIATION.

Narrator: SOMEHOW, CORALS MANAGE TO SURVIVE,

EVEN THRIVE, IN SHALLOW TROPICAL WATERS,

WHERE ULTRAVIOLET IS AT ITS STRONGEST.

BEHIND THE SCENES AT THE LONDON AQUARIUM,

SOME NEWLY GROWN CORAL MAY PROVIDE A CLUE

AS TO HOW THEY DO IT.

ONE THEORY SUGGESTS THE MARINE CREATURES

MAY HAVE EVOLVED A MECHANISM

TO COPE WITH THE HIGH-ENERGY RADIATION.

O' Malley-James: THEY HAVE THESE FLUORESCENT PIGMENTS

INSIDE THEM.

SO, AS THE UV FROM THE LAMP HITS THE FLUORESCENT PROTEINS

ON THE OUTSIDE OF THE CORAL,

THEY'RE ACTING LIKE A SORT OF SHIELD,

AND THEY'RE ABSORBING THE HIGH-ENERGY UV LIGHT

AND ALMOST INSTANTLY CONVERTING THAT INTO A LOWER-ENERGY,

HARMLESS FORM OF LIGHT.

SO IT IS LIKE A GLOWING FORM OF SUNSCREEN.

Narrator: BY CONVERTING THE UV LIGHT INTO VISIBLE LIGHT,

THE CORAL POLYPS ARE PROTECTING THEMSELVES FROM HARM.

AND JACK BELIEVES THIS PROCESS COULD BE HAPPENING

ELSEWHERE IN THE UNIVERSE.

O'Malley-James: SO, IT COULD, IN THEORY, BE HAPPENING ANYWHERE

WHERE THERE'S HIGH LEVELS OF UV RADIATION,

SUCH AS THE PLANETS IN THE TRAPPIST-1 SYSTEM

OR PLANETS AROUND SIMILAR STARS WE'RE STARTING TO FIND NOW.

THIS MECHANISM COULD ACTUALLY MAKE THOSE WORLDS

A LOT MORE HABITABLE FOR LIFE, RATHER THAN LESS HABITABLE.

Narrator: MANY SCIENTISTS THINK IT'S POSSIBLE

THAT LIFE DOES EXIST ON THE TRAPPIST PLANETS --

IN PARTICULAR, THE PLANET RIGHT IN THE MIDDLE, TRAPPIST-1e.

AND IF BIOFLUORESCENT ORGANISMS ARE THRIVING THERE,

IT COULD HAVE AN EXTRAORDINARY EFFECT ON THE EARTH-LIKE WORLD.

♪

O'Malley-James: AS A FLARE HIT, YOU'D SEE THIS PLANET LIGHT UP

WITH A GLOW OF WHATEVER COLOR IT WAS FLUORESCING,

SO YOU COULD IMAGINE THIS PLANET THAT HAS A VAGUE OUTLINE

THAT SUDDENLY BECOMES BRIGHT GREEN IN THE SKY.

Narrator: A BEAUTIFUL SIGHT.

BUT IF JACK O'MALLEY-JAMES IS RIGHT,

THE GLOWING PLANET COULD HAVE A SIGNIFICANCE BEYOND ITS BEAUTY.

LIKE A GREAT ASTRONOMICAL BEACON,

IT COULD ONE DAY BETRAY THE PRESENCE OF ALIEN LIFE.

♪

♪

Narrator: TODAY, DETECTING SIGNS OF LIFE

ON AN EARTH-SIZED EXOPLANET

IS NOT YET POSSIBLE, EVEN WITH THE WORLD'S BIGGEST TELESCOPES.

BUT IN THE ATACAMA DESERT IN CHILE,

THAT IS ABOUT TO CHANGE.

DR. JULIEN MILLI IS PREPARING FOR A PROJECT

THAT WILL TRANSFORM THE SEARCH FOR LIFE

ELSEWHERE IN THE GALAXY.

♪

Milli: WE ARE LOOKING FOR LIFE,

OR TO FIND HINTS THAT THERE IS LIFE ON OTHER PLANETS.

AND IT'S MUCH MORE LIKELY TO FIND LIFE ON ROCKY PLANETS

THAN ON GAS GIANTS,

SO THIS IS WHY WE WANT TO GO FOR THOSE FAINT ROCKY PLANETS

THAT ARE MUCH DIFFICULT TO CATCH,

BUT ALSO MUCH MORE REWARDING, POTENTIALLY.

Narrator: TO FIND THOSE ROCKY PLANETS,

ASTRONOMERS NEED BIGGER TELESCOPES.

JUST DOWN THE ROAD FROM THE VERY LARGE TELESCOPE,

CONSTRUCTION HAS BEGUN ON THE EXTREMELY LARGE TELESCOPE,

OR ELT.

Milli: SO, THE NEW TELESCOPE WILL BE FIVE TIMES BIGGER,

SO IT MEANS IT WILL BE

THE BIGGEST OPTICAL TELESCOPE ON EARTH.

AND WITH THAT, WE'LL BE ABLE TO SEARCH FOR PLANETS

THAT ARE MUCH FAINTER,

AND WE'LL BE ABLE TO GO FROM THE REGIME OF GIANT PLANET

TO SMALLER PLANETS AND MAYBE ROCKY PLANETS.

Narrator: ONCE COMPLETE, THE ELT WILL BE

THE BIGGEST OPTICAL TELESCOPE IN THE WORLD.

ITS 128-FOOT MIRROR WILL COLLECT 100 MILLION TIMES

MORE LIGHT THAN THE HUMAN EYE, ALLOWING IT TO DETECT

CRUCIAL DETAILS ABOUT EARTH-SIZED PLANETS.

WE COULD FIND SOME SIGNATURE OF LIFE.

SO, TO DO THAT, WE WOULD NEED TO ANALYZE

THE ATMOSPHERE OF THOSE PLANETS.

WE'RE LOOKING FOR A COMBINATION THAT COULD ONLY BE PRODUCED

IF THERE IS A BIOLOGICAL PROCESS.

Narrator: AS WELL AS NEW GROUND-BASED TELESCOPES,

THE JAMES WEBB SPACE TELESCOPE

SHOULD REVEAL UNPRECEDENTED NEW DETAILS

ABOUT ALIEN PLANETS AFTER ITS LAUNCH,

PLANNED FOR 2021.

THESE MASSIVE NEW TELESCOPES

WILL GIVE ASTRONOMERS THE BEST CHANCE

OF FINDING EVIDENCE OF ALIEN LIFE.

Milli: I WOULD FEEL EXTREMELY REWARDED, OF COURSE,

TO DETECT SIGNS OF LIFE,

WHICH WOULD BE AN AMAZING DISCOVERY,

AND IT'S ACTUALLY ONE OF THE GOALS OF THIS BIG TELESCOPE

IS TO LOOK FOR LIFE.

Narrator: ANSWERING THE QUESTION OF WHETHER WE'RE ALONE

IN THE UNIVERSE COULD BE A FEW SHORT YEARS AWAY.

IN THE MEANTIME, ASTRONOMERS ARE LINING UP

AS MANY EARTH-SIZED PLANETS AS POSSIBLE

SO THEY CAN BE SCANNED FOR SIGNS OF LIFE

AS SOON AS THE NEW TELESCOPES ARE READY.

♪

50 MILES ACROSS THE CHILEAN DESERT,

MICHAEL GILLON IS ALSO BUILDING A NEW OBSERVATORY --

THIS TIME, WITH FOUR TELESCOPES, WHICH HE HAS NAMED "SPECULOOS."

♪

TRAPPIST-1 HAS PROVED BEYOND ANY DOUBT

THAT RED DWARFS REALLY ARE GOOD TARGETS FOR PLANET HUNTING,

SO MICHAEL PLANS TO STAKE OUT A LOT MORE OF THEM.

SO, 1,000 OF THEM THAT ARE NEARBY ENOUGH TO MAKE POSSIBLE

IF WE DETECT AN EARTH-SIZE PLANET

TO SEARCH FOR TRACES OF LIFE IN THE ATMOSPHERE OF THESE PLANETS.

Narrator: IF THE TELLTALE SIGNS OF LIFE ARE ONE DAY FOUND

IN A SYSTEM LIKE TRAPPIST-1, IT WOULD CONFIRM

THAT ORGANISMS CAN AND DO THRIVE AROUND RED DWARF STARS,

AND THAT MATTERS

BECAUSE THERE ARE MORE OF THEM OUT THERE THAN YOU MIGHT THINK.

♪

NOT A SINGLE RED DWARF STAR IS VISIBLE TO THE NAKED EYE,

BUT IF YOU COULD SEE RED DWARFS AS CLEARLY AS OTHER STARS,

THE SKY WOULD LOOK VERY DIFFERENT --

IN FACT, THERE ARE MORE RED DWARFS

THAN ANY OTHER KIND OF STAR,

WITH AROUND 200 BILLION OF THEM IN OUR GALAXY ALONE.

AND RECENT STUDIES SUGGEST

THEY'RE USUALLY ACCOMPANIED BY SMALL PLANETS.

Gillon: IT SEEMS THAT THESE KIND OF PLANETS ARE VERY COMMON

AROUND THESE SMALL STARS,

AND WITH THE SUM OF ALL THE RED DWARFS IN OUR GALAXY,

YOU COULD END WITH -- I DON'T KNOW --

THOUSANDS OF BILLIONS OF PLANETS OVER THERE.

♪

Narrator: ONE DAY, THE SEVEN WORLDS OF TRAPPIST-1

MAY NOT SEEM SO UNIQUE AFTER ALL,

WITH A GALAXY BRIMMING WITH EARTH-SIZED PLANETS

ORBITING RED DWARF STARS.

AND IF SOMEONE DOES FIND TRACES OF LIFE ON ONE OF THESE WORLDS,

IT WOULD HAVE PROFOUND IMPLICATIONS

ABOUT THE NATURE OF THE UNIVERSE.

Gillon: IF YOU WOULD DETECT LIFE ON A NEARBY RED DWARF,

IT PROBABLY MEANS THAT LIFE IS EVERYWHERE IN THE UNIVERSE,

THAT LIFE IS A COSMIC PHENOMENON.

Narrator: WITHIN A DECADE, WE MAY DISCOVER

THAT FAR FROM BEING ALONE, WE ARE SURROUNDED BY LIFE,

THAT THE UNIVERSE IS TEEMING WITH IT.

♪