Narrator:
THE LANDSCAPES OF EARTH
HAVE BEEN SHAPED BY VOLCANOES.
WE'VE LONG BEEN IN AWE OF THEIR
DESTRUCTIVE BEAUTY,
BUT ONLY RECENTLY
HAVE WE DISCOVERED
THAT VULCANISM EXISTS
BEYOND EARTH.
THE PLANETS AND MOONS
OF THE SOLAR SYSTEM
HAVE VOLCANOES THAT ARE
EVEN MORE EXTRAORDINARY
THAN THOSE ON
OUR HOME PLANET,
BUT WHAT'S MOST REMARKABLE
IS WHAT VOLCANIC
ACTIVITY ELSEWHERE
IN THE SOLAR SYSTEM
HAS TOLD SCIENTISTS ABOUT
OUR OWN PLANET, EARTH,
WHAT THE EARTH
WAS LIKE AT ITS BIRTH,
WHY WE HAVE THE GEOLOGY
AND THE ATMOSPHERE WE DO
AND EVEN HOW LIFE ON EARTH,
AND POSSIBLY ELSEWHERE,
ORIGINATED.
**
-- Captions by VITAC --
www.vitac.com
CAPTIONS PAID FOR BY
DISCOVERY COMMUNICATIONS
THE VOLCANOES ON EARTH TODAY
ARE SOME OF THE MOST
DANGEROUS FORCES ON THE PLANET,
BUT THEY ARE ALSO CREATIVE,
FORMING NEW LAND
AND EVEN THE ATMOSPHERE
THAT SUPPORTS LIFE.
TO UNDERSTAND HOW WE GOT HERE,
WE NEED TO KNOW
WHAT EARTH WAS LIKE
4 BILLION YEARS AGO,
A TIME WHEN THE WHOLE PLANET
WAS A SEETHING SEA
OF MOLTEN ROCK.
FAR OUT IN THE SOLAR SYSTEM,
ORBITING THE HUGE PLANET,
JUPITER,
THERE IS A MOON THAT MIRRORS
THESE CONDITIONS
OF THE EARLY EARTH.
MORE VOLCANIC THAN
ANY OTHER PLANETARY BODY,
THIS MOON HAS GIVEN
SCIENTISTS A WINDOW
INTO OUR OWN PAST.
THAT'S WHY OUR STORY
BEGINS ON IO.
ASHLEY DAVIES IS A PLANETARY
VULCANOLOGIST FOR NASA.
HE'S LONG BEEN FASCINATED
BY THE MOON OF IO.
THAT'S EVER BEEN COLLECTED
BY ANY SPACECRAFT
WAS OBTAINED
BY VOYAGER AT IO.
RISING ABOVE IO'S SURFACE.
NO ONE KNEW QUITE WHAT THIS WAS.
COULD IT BE ANOTHER
MOON BEHIND IO
OR SOME ARTIFACT IN THE IMAGE?
AND THEN IT WAS REALIZED
THAT THIS WAS ACTUALLY
A HUGE VOLCANIC PLUME
RISING UP FROM IO'S SURFACE.
Narrator: WE NOW KNOW THAT,
CRAMMED INTO IO,
THE SAME SIZE AS OUR MOON,
ARE OVER 400
ACTIVE VOLCANOES.
COMPARE THIS TO JUST 60
ON THE WHOLE OF EARTH.
THE MOST POWERFUL ERUPTION
WAS SEEN AT A VOLCANO
CALLED SURT.
A FISSURE OPENED UP,
AND A HUGE VOLUME OF LAVA
LITERALLY GUSHED OUT
OF THE GROUND
TO FORM LARGE LAVA
FOUNTAINS KILOMETERS HIGH.
Narrator: WHEN SURT ROARS,
IT SENDS PLUMES OF LAVA
AND ASH OVER
300 MILES INTO SPACE.
**
IO PROVED FOR THE FIRST TIME
THAT EARTH WASN'T ALONE
IN HAVING ACTIVE VOLCANOES.
THE REASON WHY IO IS
SO ACTIVE IS IT'S CAUGHT
IN THIS GRAVITATIONAL TUG-OF-WAR
BETWEEN JUPITER,
IO, EUROPA AND GANYMEDE,
AND THIS PUMPS A LOT
OF ENERGY INTO THE SYSTEM.
**
Narrator:
THE GRAVITATIONAL FORCES
TWIST AND TURN IO,
CAUSING INTERIOR HEATING.
THIS HEATING MANIFESTS
AT THE SURFACE
IN THE FORM OF HUGE VOLCANOES.
OUR OWN PLANET, EARTH,
IS NOT SQUASHED AND SQUEEZED.
MUCH OF ITS INTERNAL HEAT
COMES FROM WHEN IT FIRST FORMED.
BUT IO IS HEATED UP SO MUCH,
IT MIGHT ERUPT AN EXTREMELY RARE
AND HOT FORM OF LAVA
CALLED ULTRAMAFIC.
ULTRAMAFIC LAVA WAS ABUNDANT
4 BILLION YEARS AGO
AS THE EARTH WAS BORN,
BUT NO LONGER.
TO DISCOVER THIS PRIMITIVE LAVA
ON IO WOULD OFFER SCIENTISTS
A WINDOW ON THE PAST.
VULCANOLOGIST ROSALY LOPES
DOES HER RESEARCH IN HAWAII.
WE'RE STUDYING
VOLCANOES ON HAWAII
NOT BECAUSE OF HAWAII ITSELF,
BUT BECAUSE HAWAIIAN VOLCANOES
ARE SUCH A GOOD ANALOG,
OR A MIRROR, IF YOU LIKE,
FOR VOLCANOES
ON JUPITER'S MOON, IO.
Narrator:
ROSALY WILL MEASURE THE COOLING
RATE OF THE LAVA HERE IN HAWAII
AND THEN APPLY IT
TO THE VOLCANOES OF IO.
IN THIS WAY,
SHE HOPES TO FIND OUT
IF IO HAS THE ESPECIALLY
HOT ULTRAMAFIC LAVA.
THE TEAM USES A THERMAL CAMERA.
YEAH, THIS SHOULD
MAKE NICE IMAGES.
OH, VERY NICE.
VERY NICE.
AND THEN JUST REALLY
HOT IN THE MIDDLE.
BUT THAT'S
COOLING SO FAST.
WOW, THAT'S BEAUTIFUL,
JUST SPECTACULAR.
THE HOTTEST LAVA IS
THE MOMENT IT EMERGES.
EVEN ON THE HOTTEST PART,
IT WAS ONLY ABOUT 910 CELSIUS.
THE MELTING TEMPERATURE OF THIS
ROCK IS ABOUT 1200 CELSIUS.
SO THAT TELLS YOU THAT,
EVEN IN THOSE RED-HOT PARTS,
THE LAVA HAS COOLED,
YOU KNOW, MORE THAN
A COUPLE HUNDRED CELSIUS.
SO LAVA COOLS VERY, VERY FAST.
Narrator: ROSALY SUSPECTS
THIS ALSO HAPPENS ON IO.
SPACE PROBES TO IO HAVE REVEALED
THAT THE SURFACE HOT SPOTS
ARE 1200 DEGREES.
IT MEANS THE TEMPERATURE
OF THE LAVA
JUST BELOW THE SURFACE OF IO
MUST BE AROUND 1400 DEGREES.
LAVA THIS HOT IS STRONG
EVIDENCE IT'S ULTRAMAFIC,
**
AN EXCITING FINDING AS IT MEANS
IO COULD HOLD THE SECRETS
OF THE EARTH'S PAST.
IO'S A MODEL OF THE EARLY EARTH
BECAUSE THE LAVAS ON IO
MAY BE OF THE ULTRAMAFIC TYPE,
AND THOSE ARE LAVAS THAT ARE
VERY HOT, VERY PRIMITIVE,
AND THEY ERUPTED ON EARTH
BILLIONS OF YEARS AGO.
Narrator:
THE MORE WE RESEARCH IO,
THE MORE WE FIND OUT
WHAT THE EARTH
WAS LIKE AS IT WAS FORMING:
THE TYPE OF LAVA FLOWS,
THE FORM OF VULCANISM,
THE TREMENDOUS DENSITY
OF VOLCANOES.
SO IO REVEALS WHAT
PRIMITIVE EARTH WAS LIKE:
DANTE'S VOLCANIC INFERNO.
**
ALTHOUGH THE EARTH OF TODAY
IS FAR LESS VOLCANIC
THAN IT ONCE WAS,
IT REMAINS GEOLOGICALLY
A VERY ACTIVE PLANET.
A GOOD WAY OF UNDERSTANDING
WHY EARTH STILL RETAINS
MUCH OF ITS VULCANISM
IS TO CONTRAST IT
WITH OTHER PLANETARY BODIES
THAT MIGHT HAVE LOST
THEIR VULCANISM.
Man: 3, 2, 1, LIFT OFF.
Narrator:
THE APOLLO MISSIONS WEREN'T
JUST ABOUT THE SPACE RACE.
THEY WERE ALSO
THE MOST AMBITIOUS
GEOLOGICAL FIELD TRIPS
OF ALL TIME.
A KEY AIM WAS TO DISCOVER
IF VOLCANOES HAD
HELPED CREATE THE MOON,
AND IF SO,
WERE ANY STILL ACTIVE?
IN THE 1960S, JIM HEAD
WAS A KEEN, YOUNG GEOLOGIST
WHO HAD TO TEACH THE ASTRONAUTS
ALL ABOUT ROCKS.
BEFORE THE APOLLO PROGRAM,
WE DIDN'T EVEN KNOW
WHETHER THE MOON HAD VULCANISM.
FOR EXAMPLE, SOME PEOPLE
THOUGHT IT WAS A COLD MOON.
SOME PEOPLE THOUGHT
IT WAS A WARM MOON,
WHICH HAD HEATING
INSIDE AND VULCANISM.
SO THIS IS A BIG QUESTION:
WAS IT EVEN VOLCANIC ROCK?
Narrator:
THESE DARK-LOOKING PLAINS
OF THE MOON WERE PARTICULARLY
TANTALIZING TO SCIENTISTS.
THEY'RE CALLED THE SEAS,
OR THE MARIA.
-BEAUTIFUL VIEW.
-ISN'T THAT SOMETHING?
Man: MAGNIFICENT DESOLATION.
Narrator: TO FIND OUT EXACTLY
WHAT THEY WERE,
THE FIRST APOLLO LANDING
WAS TO MARE TRANQUILLITATUS,
THE SEA OF TRANQUILITY.
Man #1: OKAY. ARE YOU READY
FOR ME TO COME OUT?
Man #2: ALL SET.
AS THE ASTRONAUTS EXPLORED
THE DUSTY AND ROCKY SURFACE,
THEY RECOGNIZED BASALT,
THE MOST COMMON VOLCANIC
ROCK FOUND ON EARTH.
IF THE LAVA IS COMING UP
FROM GREAT DEPTHS,
GIVEN THE GRAVITY, ETCETERA,
YOU'LL GET A LOT
OF LAVA COMING OUT,
COMMONLY MUCH MORE
THAN YOU SEE ON THE EARTH,
AND SO IT FLOWS
GREAT DISTANCES.
AND SO WE HAVE LAVA FLOWS
THAT GO OVER 1,000 KILOMETERS.
LIKE, INCREDIBLE.
IT WOULD GO HALFWAY ACROSS
THE UNITED STATES, NO PROBLEM.
Narrator: ANOTHER MYSTERIOUS
FEATURE FOUND ON THE MOON
WAS THESE WINDING CANYONS
OR SINUOUS RILLS.
THESE CHANNELS WERE UP
TO 1,300 FEET DEEP
AND OVER 60 MILES LONG.
CLUES AS TO WHAT CREATED THEM
CAN BE FOUND BACK ON EARTH.
Narrator: THE COUNTRY OF ICELAND
HAS AN EXTRAORDINARY RANGE
OF GEOLOGICAL FEATURES.
THIS CURIOUS TUNNEL THROUGH
SOLID ROCK APPEARS
ALMOST MAN-MADE.
GRO PEDERSEN WANTS TO TRACK DOWN
WHAT USED TO FLOW THROUGH IT.
Pedersen: YOU CAN ACTUALLY SEE
HOW THE LAVA HAS BEEN
RUNNING ALONG THE WALL HERE.
AND YOU CAN SEE ALSO
THAT IT WAS VERY HOT IN HERE
BECAUSE SOME OF THIS LAVA
REMELTED AND BASICALLY
WENT DRIBBLING DOWN THE WALL.
YOU SEE THAT HERE.
Narrator: IT'S A LAVA TUBE,
AND LONG AGO,
LAVA WAS SURGING
THROUGH THESE TUNNELS.
ONE OF THE VERY EXCITING
THINGS PEOPLE FOUND ON THE MOON
WAS THESE SINUOUS RILLS,
AND, OF COURSE,
BEFORE PEOPLE HAD
ACTUALLY BEEN ON THE MOON
THEY WERE THOUGHT TO
POTENTIALLY BE WATER-ERODED.
BUT THEN PEOPLE HAVE
GONE TO THE MOON,
AND IT HAS BEEN
STUDIED MUCH MORE,
AND WE HAVE FOUND OUT
THAT THESE SINUOUS RILLS
WERE ALWAYS CONNECTED
WITH THE MARIA,
THE MOON LAVAS,
THAT WE HAVE UP THERE.
Narrator:
PERHAPS THESE SINUOUS RILLS
WERE ONCE ENCLOSED LAVA TUBES.
SO ONE OF THE THINGS
THAT YOU SEE HERE, OBVIOUSLY,
IS THAT WE HAVE
WHAT WE CALL SKY LIGHTS.
SO THE ROOF HAS COLLAPSED.
IF ALL OF THE ROOF COLLAPSES,
YOU WILL END UP WITH A VALLEY
LIKE SOMETHING
YOU SEE ON THE MOON.
BUT YOU CAN ALSO SEE THE TUBES
ON THE MOON
BY A STRING OF SKYLIGHTS,
JUST AS WE SEE HERE,
ONE HOLE AFTER THE OTHER,
AND YOU JUST FOLLOW THEM.
YOU TRACE THEM DOWN,
AND YOU CAN SEE
THAT THESE ARE
WITHIN LAVA FLOWS.
Narrator: BUT WHEN DID THESE
ERUPTIONS TAKE PLACE?
AND WHY DID THEY
EVENTUALLY STOP?
THE ANSWER WOULD COME
IN SMALL BAGS OF VOLCANIC ROCKS
BROUGHT HOME BY THE ASTRONAUTS.
ON EARTH, THEY COULD BE
ACCURATELY DATED.
SO, WHEN THE MOON ROCKS
WERE BROUGHT BACK,
IT'S, LIKE, UNBELIEVABLE!
OKAY.
THIS WE CAN TELL
4-BILLION-YEAR-OLD ROCKS.
THIS IS THE KEYS
TO THE UNDERSTANDING
OF THE SOLAR SYSTEM.
Narrator: LIKE OTHER PLANETARY
BODIES MADE OF ROCK,
THE MOON WAS A MASS
OF HOT MOLTEN MAGMA
AS IT WAS FORMING.
IT'S AN AMAZING THOUGHT
THAT YOU COULD HAVE BEEN
STANDING ON EARTH
AND LOOKED UP AT THE MOON
AND SEE THESE MASSIVE
ERUPTIONS HAPPENING.
[ MOON RUMBLING ]
Narrator: BUT, ALL THE TIME,
IT WAS COOLING.
BEING RELATIVELY SMALL,
A QUARTER OF THE DIAMETER
OF THE EARTH,
THE MOON COOLED DOWN QUICKLY.
BY 3 BILLION YEARS AGO,
ALMOST ALL THE LAVA
AND INTERIOR MAGMA
HAD SOLIDIFIED
INTO ONE BIG LUMP OF COLD ROCK.
NO MORE VOLCANOES.
BUT YOU SEE THE REMNANTS OF IT.
I MEAN, WHEN YOU LOOK AT THE SKY
AND YOU LOOK AT THE MOON,
YOU SEE THE EVIDENCE
OF THE VULCANISM
BECAUSE YOU SEE THE DARK AREAS,
THE BASALT, WHICH HAS FILLED
IN THE CRATERS.
Narrator:
BUT THE EARTH WAS MUCH LARGER,
AND THIS HELPED IT
RETAIN LOTS OF ITS
ORIGINAL HEAT AND MAGMA.
AND SO, TODAY, OUR PLANET
IS A DYNAMIC
AND EVER-CHANGING WORLD
RATHER THAN A DEAD ONE.
SO THE LUNAR EXPLORATION
REALLY OPENED UP A FIELD
OF REALLY PLANETARY VOLCANOLOGY.
Narrator:
ONE OF THE FIRST OF OUR
NEIGHBORING PLANETS
TO BE STUDIED
IN DETAIL WAS MARS,
THE RED PLANET.
**
RESEARCH ON MARS HAS ALSO
REVEALED MORE ABOUT THE GEOLOGY
OF OUR OWN PLANET, EARTH.
THIS IS BECAUSE IT SOON
BECAME APPARENT THAT MARS
ALSO HAD ASTONISHING VOLCANOES.
WHEN THE PROBES FIRST
REACHED THE RED PLANET,
ONE FEATURE STOOD OUT
ABOVE SWIRLING SAND STORMS:
THE VOLCANO OLYMPUS MONS.
OLYMPUS MONS IS ENORMOUS.
IT'S ABOUT 2,500
KILOMETERS HIGH.
MOST COMMERCIAL AIRCRAFT FLY
AT 10 TO 15 KILOMETERS,
SO YOU'RE LOOKING AT SOMETHING
THAT'S TOWERING WAY ABOVE
WHAT COMMERCIAL
AIRCRAFT MIGHT FLY.
Narrator:
IT'S 3 TIMES THE HEIGHT
OF MOUNT EVEREST,
MAKING IT THE LARGEST VOLCANO
EVER DISCOVERED
IN THE SOLAR SYSTEM.
FINDING OUT HOW IT GREW TO BE
SO COLOSSAL TELLS SCIENTISTS
MORE ABOUT
THE VOLCANOES OF EARTH.
A TEAM OF VULCANOLOGISTS
IS INVESTIGATING
THIS MOUNTAIN IN ICELAND
TO COMPARE IT
TO OLYMPUS MONS.
IT'S CALLED SKJALDBREIDUR,
WHICH MEANS BROAD SHIELD,
AS ITS SLOPES
ARE REMINISCENT OF A SHIELD.
ALTHOUGH SMALL IN STATURE,
IT'S OF GREAT SIGNIFICANCE.
THIS SHIELD VOLCANO IS
THE ONE OVER OR ABOUT
WHICH ALL THE OTHER VOLCANOES
OF THIS TYPE ARE CALLED,
IN OUR SOLAR SYSTEM
AND ON THE EARTH.
SO THIS IS THE FIRST
ONE IN MANY SENSES,
THE FIRST ONE TO BE
NAMED THE SHIELD.
IT'S ONLY ABOUT 1/2 MILE HIGH,
JUST A TWENTY-FIFTH
THE HEIGHT OF OLYMPUS MONS,
BUT CRUCIALLY,
IT'S THE SAME TYPE
OF SHIELD VOLCANO.
AT THE SUMMIT IS THE CRATER.
AROUND THE RIM ARE
MYSTERIOUS SHAPED ROCKS.
THEY LOOK ALMOST LIKE
FOSSILIZED SNAKES,
YET THEY GIVE A HINT
HOW THIS TYPE OF VOLCANO FORMS
AND WHAT GIVES IT
THE DISTINCTIVE SHIELD SHAPE.
SHIELD VOLCANOES COMPRISE LAVAS
THAT ARE VERY RUNNY
BECAUSE OF THE SHAPE OF THEM.
THIS BROAD SHIELD SHAPE
TELLS US IT HAS TO BE.
AND WE HAVE THE EVIDENCE
IN FRONT OF OUR EYES
OF THESE SMALL TUBES,
THESE ENTRAILS RUNNING DOWN
THE SIDES OF THE VOLCANO,
TELLING US INDEED THAT IT
HAS TO BE VERY RUNNY.
Narrator: THIS FAST-FLOWING LAVA
CREATES THE GENTLE SLOPES
OF ALL SHIELD VOLCANOES,
INCLUDING THE LARGEST
ONE OF ALL ON MARS.
BUT, WHILE SHIELD
VOLCANOES IN ICELAND
HAVE JUST ONE CRATER
AT THE SUMMIT,
OLYMPUS MONS HAS SIX
OVERLAPPING CRATERS.
THAT'S A KEY.
WE ACTUALLY CAN USE
WHAT WE SEE IN ICELAND
TO SAY WHAT WE SEE ON MARS
IS SIMILAR BUT ALSO DIFFERENT.
IT HAS TO BE MUCH,
MUCH LONGER LIVED
WITH MULTIPLE PHASES
OF ERUPTIONS
TO PRODUCE THESE
MULTIPLE SUMMIT CRATERS
WE SEE ON OLYMPUS MONS.
**
Narrator: WHEN THIS BEHEMOTH
ERUPTED, MARS SHUDDERED.
[ VOLCANO RUMBLING ]
BUT EARTH IS TWICE
THE SIZE OF MARS.
SO WHY DON'T WE HAVE VOLCANOES
AS ENORMOUS AS OLYMPUS MONS?
Narrator: MARS IS HOME
TO THE SOLAR SYSTEM'S
MOST MASSIVE VOLCANO,
OLYMPUS MONS,
AND IT DWARFS ANYTHING ON EARTH.
HOW IS THAT POSSIBLE, GIVEN
EARTH IS TWICE THE SIZE OF MARS?
IT'S ALL TO DO
WITH PLATE TECTONICS.
EARTH IS MADE UP OF SEVEN
HUGE PLATES DRIFTING ABOVE
A SEA OF MAGMA.
THE CIRCULATION OF MAGMA
RECYCLES ROCKS AND GASES,
BRINGING THEM TO THE SURFACE
AND THEN BACK DOWN AGAIN.
ICELAND IS THE PERFECT PLACE
TO WITNESS
PLATE TECTONICS IN ACTION.
THIS RIFT IS WHERE
THE NORTH AMERICAN PLATE
TO THE LEFT DIVIDES
FROM ITS EURASIAN COUSIN
TO THE RIGHT.
THE RIFT IS WIDENING
RAPIDLY AT AN INCH A YEAR.
MARS, LIKE ALL OTHER
PLANETS WE KNOW OF,
HAS NO ACTIVE PLATE TECTONICS.
THE ENTIRE CRUST OF MARS
REMAINS LOCKED IN PLACE
WITH REPERCUSSIONS
FOR ITS VOLCANOES.
ANY UPWELLING MAGMA
CONTINUALLY BREAKS THROUGH
AT ONE FIXED LOCATION.
SO IT'S A VERY FOCUSED ERUPTION
OF MAGMA FOR BILLIONS OF YEARS,
AND WHAT HAPPENS
IS YOU JUST END UP
WITH A HUGE VOLCANO,
THE BIGGEST
IN THE SOLAR SYSTEM.
WHILE MARS IS NO LONGER
VOLCANICALLY ACTIVE,
IT DOES SHARE AN IMPORTANT
FEATURE WITH EARTH:
THE POLAR ICE CAPS.
THE STORY OF THESE ICE CAPS
HAS BEEN REVEALED
THROUGH UNUSUALLY
SHAPED VOLCANOES.
THEY HAVE STEEP SIDES
AND A FLAT TOP LIKE A TABLE.
SCIENTISTS NOW BELIEVE
THEY MIGHT HAVE BEEN FORMED
WHEN VOLCANOES EXPLODED
THROUGH AN ANCIENT ICE SHEET.
**
TO UNDERSTAND HOW ICE
CAN CHANGE THE BEHAVIOR OF LAVA,
SCIENTISTS ARE CARRYING OUT
AN EXTREME EXPERIMENT.
FOR THIS, INGO SONDER
AND TRACY GREGG
NEED TO MAKE THEIR OWN LAVA
OUT OF 110 POUNDS
OF BASALT ROCK.
WE'RE TURNING IT
TO ITS LAVA STATE,
AND THE STUDENTS HAVE
BUILT A LITTLE RAMP
THAT THE LAVA WILL POUR DOWN
AND POOL AT THE END.
AND, AT THE END
OF THIS LAVA STREAM,
THERE WILL BE
A LITTLE POND OF ICE,
SO THE LAVA'S GOING
TO FLOW OVER THE ICE.
WE THINK WE KNOW
THIS HAS HAPPENED ON EARTH.
WE THINK IT'S HAPPENED
ON MARS IN THE PAST,
SO WE'LL SEE WHAT HAPPENS.
**
OKAY.
LOOK WHERE IT HITS THE ICE.
IT'S BOILING
BECAUSE THE ICE
IS MELTING AND THEN
FLASHING TO STEAM,
AND IT'S CREATING ALL THOSE
BUBBLES THERE ON THE LAVA.
WHOA! AND NOW THIS IS
WHAT HAPPENS
[CHUCKLES] WHEN THE LAVA
MELTS THE ICE
AND THERE'S ENOUGH WATER.
WE'RE GETTING SOME LITTLE
STEAM EXPLOSIONS.
ALL RIGHT. THERE'S NO MORE LAVA
COMING OUT OF THE FURNACE,
BUT UNDERNEATH THAT BLACK CRUST,
IT'S STILL LIQUID.
IT'S SLOWLY FLOWING DOWN,
AND YOU CAN SEE IT
WHERE IT'S CLIMBING
OVER THE ICE.
THERE'S SOME HEAVING GOING ON
AS GAS IS TRYING TO ESCAPE.
Narrator: THE EXPERIMENT
LETS TRACY IDENTIFY KEY FEATURES
AS MOLTEN ROCK
INTERACTS WITH ICE.
WHEN THE LAVA HIT THE ICE,
A COUPLE OF THINGS
HAPPENED REALLY FAST.
THE LAVA STARTED TO BUBBLE
AS THE ICE MELTED
AND THEN FLASHED TO STEAM.
AND THEN, AS MORE MELT OCCURRED,
THERE WERE ACTUALLY
PUDDLES OF WATER
THAT STARTED TO BOIL AND SPATTER
JUST LIKE ON YOUR STOVE,
RIGHT, THE WATER SPATTERING.
WHERE THE ICE WASN'T,
WE HAVE A NICE, NEAT,
ORGANIZED FOLDS IN THE LAVA.
AND, RIGHT WHERE THE ICE STARTS,
WE GET THESE BIGGER BUBBLES
ON THE SURFACE.
LOOK, THAT ONE'S BROKEN OPEN.
YOU CAN SEE INSIDE.
THAT'S THE KIND OF THING
WE COULD LOOK FOR ON MARS,
RIGHT,
TO SEE IF THERE WAS
ANY LAVA-ICE
INTERACTIONS ON MARS.
Narrator: THE ARTIFICIAL VOLCANO
CONFIRMS THAT LAVA BEHAVES
VERY DIFFERENTLY
WHEN IT MEETS ICE.
BUT WHAT HAPPENS OUT
IN THE REAL WORLD?
Narrator: MODERN-DAY VOLCANOES
ON ICELAND GIVE US CLUES
TO HOW UNIQUE FORMATIONS
ON MARS WERE CREATED.
ONE OF THE MOST DISTINCTIVE
TYPES OF VOLCANO IN ICELAND
IS CALLED A TUYA.
THAT LOOK LIKE THIS ON ICELAND,
HAS BEEN THERE,
OF VOLCANOES ON MARS,
WE'VE GOT A VERY GOOD IDEA
THAT THERE WAS ICE PRESENT.
MAPPING THE TUYAS ON MARS
REVEALS THE COVERAGE IN DEPTH
OF THE ANCIENT ICE SHEETS.
THE VOLCANOES OF MARS
HAVE REVEALED MUCH ABOUT
THE GEOLOGICAL HISTORY
OF OUR OWN EARTH.
BUT VOLCANOES HAVE
PLAYED A KEY ROLE
IN THE EVOLUTION OF PLANETS
IN ANOTHER WAY:
BY CREATING THEIR ATMOSPHERE.
**
THE MOST EXTREME ATMOSPHERE
OF ALL THE PLANETS
OF THE SOLAR SYSTEM
IS FOUND ON VENUS,
AND BECAUSE IT'S SO EXTREME,
IT'S THE IDEAL PLANET
TO FIND OUT MORE ABOUT
HOW VOLCANOES HELP
MAKE AN ATMOSPHERE.
IT HAS THE DENSEST ATMOSPHERE
ANYWHERE IN THE SOLAR SYSTEM
AND ONE OF THE HOTTEST.
THIS EXTREME ATMOSPHERE WAS
ALMOST CERTAINLY LIKE THIS
BECAUSE OF VOLCANOES THAT
PUMPED OUT THESE GASES.
BUT SCIENTISTS COULD NOT CONFIRM
THIS BECAUSE THE ATMOSPHERE ALSO
HID WHAT WAS HAPPENING
ON THE PLANET'S SURFACE.
SO WE REALLY DIDN'T
HAVE MUCH IDEA
WHAT WAS BENEATH THOSE CLOUDS,
AND IT WAS A BIT OF GUESSWORK.
WHEN WE SEND A PROBE DOWN,
ARE WE GOING TO SURVIVE?
WHAT'S THE ATMOSPHERIC
PRESSURE GOING TO BE?
HOW HOT IS IT GOING TO BE?
BUT A NEW GENERATION OF PROBES,
ARMED WITH RADAR,
EVENTUALLY PEERED THROUGH
THE VEIL OF VENUS
TO REVEAL AN
ASTONISHING LANDSCAPE,
MORE VOLCANIC CONES
AND CRATERS
THAN ANY OTHER PLANET
OF THE SOLAR SYSTEM.
WE THOUGHT THIS IS A PLANET
WITH A LOT OF VOLCANOES ON IT
AND EVEN MORE
FASCINATING VOLCANOES
UNLIKE ANY WE SEE ON EARTH.
Narrator: THESE VOLCANOES
ARE UNIQUE TO VENUS.
SOME ARE 40 MILES ACROSS,
SURROUNDED BY CLIFFS
ALMOST HALF A MILE HIGH.
ALMOST PERFECTLY CIRCULAR,
THEY'RE KNOWN AS PANCAKE DOMES.
THEY'RE SO UNTYPICAL OF
WHAT ELSE WE SAW ON VENUS.
AND THAT'S WHEN PEOPLE
STARTED THINKING, WELL,
THERE'S SORT OF LAVA
FLOWS ON EARTH
WHERE WE ACTUALLY HAVE
THESE SAME FEATURES.
ARE THESE LAVA FLOWS WE HAVE
IN A PLACE LIKE ICELAND?
**
Narrator:
WHAT COULD PANCAKE DOMES TELL US
ABOUT VULCANISM ON EARTH?
THESE ARE THE EXTRAORDINARY LAVA
FLOWS AT TORFAJOKULL IN ICELAND.
THEY END IN CLIFFS SIMILAR
TO THE PANCAKE DOMES,
BUT ON A SMALLER SCALE.
DAVE MCGARVIE
AND IAN SKILLING HOPE
TO DISCOVER EVEN MORE
ABOUT THE LAVA
THAT CREATED THESE
SURREAL LANDSCAPES.
McGarvie:
SO YOU CAN SEE LOTS OF LITTLE
WHITE CRYSTALS ACTUALLY ALIGNED
IN THAT PARTICULAR DIRECTION,
AND THESE ONLY LINE UP
WHEN YOU'VE GOT SOMETHING
THAT'S VERY, VERY STICKY
AND FORCING CRYSTALS
TO ACTUALLY LINE UP
IN ONE DIRECTION.
AND, IN THIS CASE,
I KNOW THESE CRYSTALS
ARE TELLING ME THIS ROCK
IS VERY HIGH IN SILICA.
Narrator: SILICA THICKENS THE
LAVA, AND DAVE AND IAN BELIEVE
THAT THIS WAS WHAT CREATED
THE PANCAKE DOMES ON VENUS.
IT BEHAVES DIFFERENTLY
FROM THIN LAVA.
THE MOST COMMON
TYPE OF LAVA WE HAVE
IN THE SOLAR SYSTEM IS BASALT,
AND THE ENTIRE SURFACE
OF THE MOON
AND THE ENTIRE SURFACE OF MARS
IS COVERED IN BASALT,
AND I'M GOING TO ILLUSTRATE
THAT BY USING OIL.
IT SPREADS OUT WHERE
IT WANTS TO GO,
BEAUTIFUL LITTLE FINGERS
COMING DOWN THIN AND FAST.
HOWEVER, IN SOME PARTS
OF THE EARTH
AND THESE PANCAKE DOMES
ON VENUS,
WHICH IS VERY EXCITING, WE'VE
GOT THIS MUCH THICKER LAVA FLOW,
AND I'M GOING TO ILLUSTRATE
THAT WITH TREACLE.
AND LET'S SEE HOW THAT GOES.
BEAUTIFUL.
SEE HOW SLOW AND
HOW THICK IT IS?
THAT IS EXACTLY
WHAT WE EXPECT TO SEE
WHEN WE'VE GOT
THE THICKER LAVA FLOWS
THAT ARE MUCH RICHER IN SILICA.
Narrator: BUT ARE ANY VOLCANOES
ON VENUS STILL ACTIVE?
SOME EXCITING
CIRCUMSTANTIAL EVIDENCE
HAS RECENTLY BEEN DISCOVERED.
THEY FOUND THAT VENUS
HAD HOT SPOTS
WITHIN IT THAT OCCURRED OVER
QUITE A SHORT TIME AGO.
AND THIS WAS THE FIRST EVIDENCE
WE HAD OF PERHAPS
SOMETHING ACTIVE ON VENUS.
Narrator: THIS IMAGE OF
THE PLANET'S SURFACE
WAS TAKEN ON JUNE 22, 2008.
THE HOTTEST PARTS
ARE YELLOW AND RED.
AND THE SAME AREA
JUST 2 DAYS LATER.
THE BEST EXPLANATION OF THESE
NEW HOT SPOTS IS ERUPTING LAVA.
WE'RE ALSO SEEING
UNEXPLAINED SPIKES
OF SULFUR IN THE ATMOSPHERE,
WHICH ARE PROBABLY RELATED
TO THESE BURSTS
OF HOT ACTIVITY
APPEARING ON THE SURFACE.
Narrator: AND IT'S ALL THESE
ACTIVE VOLCANOES
THAT CREATE THE ATMOSPHERE.
BUT ANY ERUPTIONS HERE
WILL BE HIGHLY UNUSUAL
BECAUSE THE ATMOSPHERE
IS SO DENSE,
EQUIVALENT ON EARTH TO 1/2 MILE
DEEP BELOW THE OCEAN.
McGarvie:
I CAN'T SEE THERE BEING ANY WAY
THAT YOU'RE GOING TO GET
ANY SUBSTANTIAL AMOUNT
OF EXPLOSIVE ACTIVITY
TAKING PLACE ON VENUS,
NOTHING LIKE THE AMOUNT
WE GET ON EARTH
SIMPLY BECAUSE THE ATMOSPHERE
IS SUPPRESSING
THE EXPLOSIONS ON VENUS.
Narrator: BUT WHY HAVEN'T ALL
THE VOLCANOES OF EARTH
LED TO A SIMILAR DENSE
AND HOSTILE ATMOSPHERE
ON OUR OWN PLANET?
Narrator: VOLCANOES ARE KNOWN
AS FORCES OF DESTRUCTION,
BUT THEY'RE ALSO ONE OF
THE MOST POWERFUL CREATORS
ON OUR PLANET.
CLAIRE COUSINS IS
AN ASTROBIOLOGIST.
SHE'S BEEN COMING TO ICELAND
FOR 10 YEARS
AS THIS IS THE IDEAL PLACE
TO FIND OUT HOW VOLCANOES
COULD HELP SUPPORT LIFE.
CLAIRE AND HER COLLEAGUES
ARE TAPPING INTO THE GASES
OF A VOLCANIC VENT.
MANY OF THESE GASES
ARE HIGHLY TOXIC.
SO WE WEAR THESE GAS MASKS
WHILE WE'RE SAMPLING
THESE VOLCANIC GASES
BECAUSE THEY'RE WHAT
WE CALL ACIDIC GASES.
SO THEY ARE THINGS LIKE CARBON
DIOXIDE OR HYDROGEN SULFIDE,
AND THEY'RE BASICALLY GASES
THAT WE JUST DON'T WANT
TO BE BREATHING IN.
THEY'RE REALLY POISONOUS.
Narrator: BUT SURPRISINGLY,
THE MOST ABUNDANT GAS
IS ACTUALLY WATER VAPOR:
97 PERCENT AT THIS SITE.
VOLCANOES ARE NOT JUST
DESTRUCTIVE PROCESSES.
ON THE LONG TERM ESPECIALLY,
THEY PRODUCE A HUGE AMOUNT
OF ESSENTIAL INGREDIENTS
FOR LIFE, BASICALLY,
PARTICULARLY WATER.
**
Narrator:
EARTH'S EARLY ATMOSPHERE
AND OCEANS WERE CREATED
BY VULCANISM PUMPING WATER
AND GAS INTO
THE PRIMEVAL SKY.
THROUGH THIS WHOLE PROCESS,
VOLCANOES ACTUALLY DELIVER
TO THE SURFACE OF A PLANET
MANY FUNDAMENTAL INGREDIENTS
REQUIRED BY LIFE.
Narrator: IN CONTRAST, VENUS,
WITHOUT PLATE TECTONICS,
PUMPED EVER MORE GASES
INTO HER ATMOSPHERE.
OVER TIME, THIS DENSE ATMOSPHERE
CREATED A HELL PLANET.
THIS MADE IT IMPOSSIBLE FOR LIFE
TO SURVIVE ON VENUS.
BUT, ELSEWHERE
IN THE SOLAR SYSTEM,
VOLCANOES HAVE BEEN
THE CRUCIBLE FOR LIFE.
ALL LIFE THAT WE KNOW
OF NEEDS HEAT, LIQUID WATER
AND ENERGY-RICH FOODSTUFF.
ON EARTH, VOLCANOES
PROVIDE ALL THREE.
IF THEY CAN DO THIS
FOR LIFE HERE,
VOLCANOES MIGHT SUPPORT
LIFE BEYOND EARTH.
AT A VOLCANIC HOT SPOT
IN ICELAND,
CLAIRE IS SEARCHING
FOR UNUSUAL LIFE FORMS
THAT CAN SURVIVE HERE.
MICROBES THAT LIVE
IN THESE VERY HOSTILE,
VERY ACIDIC ENVIRONMENTS,
THEY'VE EVOLVED TO LIVE HERE,
AND THEY WOULDN'T ACTUALLY
GROW IN OUR CONDITIONS.
Narrator: MARS HAD VERY
SIMILAR ENVIRONMENTS
WHERE VULCANISM MET ICE.
THIS MAKES IT A GOOD CANDIDATE
FOR EVIDENCE
OF EXTRATERRESTRIAL LIFE.
ICELAND ACTS AS A USEFUL
PARALLEL, AND HERE,
CLAIRE TESTS
THE WATER FOR SULFUR,
WHICH CERTAIN BACTERIA
COULD FEED ON.
THE INTENSITY OF THE BLUE
TELLS YOU HOW MUCH SULFIDE
IS DISSOLVED IN THE WATER,
HOW MUCH FOOD THERE IS
FOR THE MICROBES TO EAT.
Narrator:
CLAIRE BELIEVES THAT LIFE
ON EARTH AND POSSIBLY MARS
COULD HAVE ORIGINATED IN
A VOLCANIC HOT SPOT
JUST LIKE THIS.
BUT MARS IS NOT
THE ONLY PLANETARY BODY
WHERE VULCANISM IS
CLOSELY LINKED TO ICE.
**
[ TELEPHONE CHIMES ]
TWO, FOUR, K, SEVEN.
Narrator:
LINDA SPILKER IS HEAD OF THE
TEAM THAT RUNS THE CASSINI PROBE
THAT'S BEEN EXPLORING
SATURN AND HER MOONS.
LINDA IS MOST INTERESTED
IN THE MOON CALLED ENCELADUS.
ENCELADUS IS ONLY ABOUT
500 KILOMETERS ACROSS,
AND IT'S ONLY ABOUT ONE-SEVENTH
THE SIZE OF OUR OWN MOON.
AND THAT TINY MOON, WE THINK,
SHOULD'VE BEEN FROZEN SOLID.
AND, IF YOU LOOK CAREFULLY,
YOU'LL NOTICE IT
DOESN'T LOOK LIKE
OUR MOON AT ALL.
OUR MOON IS COVERED
WITH CRATERS, AND IT'S DARK,
BUT THIS IS BRIGHT, ICY WHITE
AND VERY FEW CRATERS.
Narrator: AS THE CASSINI PROBE
APPROACHED ENCELADUS,
LINDA OBSERVED SOMETHING
NEVER SEEN BEFORE
ON A PLANETARY BODY.
Spilker: IF YOU LOOK CAREFULLY,
YOU CAN ACTUALLY SEE
INDIVIDUAL GEYSERS COMING UP
AND SHOOTING OUT INTO SPACE.
AND WHAT A SURPRISE.
WE JUST...
EVERYONE WAS IN AWE
AND AMAZEMENT
TO SEE THIS LEVEL OF ACTIVITY.
Narrator: THESE ERUPTIONS
ARE NOT MOLTEN ROCK.
THEY ARE GEYSERS,
WATER AND ICE FOUNTAINING
OVER 400 MILES INTO SPACE.
IT MEANS THAT LIQUID WATER,
DEEP BELOW THE SURFACE
IS BEING FORCED UPWARDS BY HEAT.
THE MATERIAL ERUPTS SO HIGH THAT
IT'S ACTUALLY BECOME
PART OF SATURN'S RINGS.
SO, ALL ALONG, VISIBLE EVIDENCE
OF VOLCANIC ACTIVITY WAS PRESENT
IN THE RINGS OF SATURN,
BUT SCIENTISTS HADN'T
EVEN REALIZED.
COMING OUT OF THE GEYSERS,
THERE'S WATER VAPOR.
THERE'S TINY PARTICLES.
IF YOU'D STAND NEAR ONE
OF THESE CRACKS ON ENCELADUS
AND PUT OUT YOUR HAND,
IT WOULD ALMOST BE
LIKE IT WAS SNOWING.
THESE TINY PARTICLES
WOULD FALL BACK DOWN.
AND THAT'S WHY
THERE'S NO CRATERS.
Narrator:
SO HOW ARE THESE EXTRAORDINARY
GEYSERS OF ICE AND WATER FORMED?
AGAIN, ICELAND PROVIDES
A POWERFUL ANALOGY.
**
THIS IS THE STROKKUR GEYSER.
Cousins: SO WHAT WE HAVE HERE,
RATHER THAN MOLTEN LAVA
COMING OUT OF THE GROUND
AS YOU TYPICALLY GET
FOR YOUR REGULAR VOLCANO,
WHAT WE HAVE HERE
IS ACTUALLY JUST WATER,
JUST GROUND WATER,
WHICH IS WITHIN THE GROUND,
AND IT'S BEING HEATED UP
BY THESE MAGMA CHAMBERS,
WHICH ARE ACTUALLY MUCH
FURTHER DEEPER UNDERGROUND.
AND THIS WATER GETS
SUPERHEATED UNTIL IT
JUST CAN'T STAY
UNDERGROUND ANYMORE,
AND ALL THAT STEAM
AND ALL THAT ENERGY,
JUST LIKE IN A NORMAL VOLCANO,
WILL JUST ERUPT ALL OF
THAT WATER TO THE SURFACE.
FOR ME, ENCELADUS IS ONE OF
THE MOST EXCITING PLACES,
I THINK, IN THE SOLAR SYSTEM
TO GO AND EXPLORE,
IT'S...
[ GEYSER ERUPTING ]
FOR REASONS EXACTLY LIKE THAT.
IT'S ONE OF THE OTHER PLACES
IN THE SOLAR SYSTEM
WHERE WE ACTUALLY HAVE THIS
ACTIVE HYDROTHERMAL ACTIVITY.
Narrator:
BUT WITH ALL THIS ACTIVITY,
DOES THIS MEAN THAT ENCELADUS
IS CAPABLE
OF HAVING LIQUID WATER?
Narrator:
SATURN'S MYSTERIOUS MOON,
ENCELADUS,
MAY HAVE SOMETHING
IN COMMON WITH EARTH.
IT MAY CONTAIN LIQUID WATER.
THE GEYSERS OF ENCELADUS
ARE SO POWERFUL,
SCIENTISTS SUSPECT
THERE MUST BE HUGE AMOUNTS
OF WATER BELOW THE ICY SURFACE.
AND SOME CLEVER DETECTIVE WORK
ON THE UNUSUAL SPIN
OF THE MOON HAS CONFIRMED
THE HIDDEN OCEAN BELOW.
**
ON ENCELADUS, 5,000
FIXED FEATURES, SUCH AS CANYONS,
WERE OBSERVED OVER TIME
TO IDENTIFY ANY TINY SHIFTS
IN POSITION.
IN THIS WAY, ASTRONOMERS
HAVE DISCOVERED
THAT THE MOON
DID INDEED WOBBLE
ABOUT ITS AXIS
A TENTH OF A DEGREE.
A WOBBLE THIS SIZE PROVED THERE
HAD TO BE AN OCEAN
SLOSHING AROUND BELOW
AND EVEN GAVE ITS DEPTH,
UP TO 20 MILES DEEP.
WE KNOW WHAT'S INSIDE
SATURN'S MOON!
WE CAN'T EVEN SAY THAT WITH
CERTAINTY ABOUT OUR OWN MOON
BECAUSE IT DOESN'T VOLUNTEER
STUFF QUITE SO READILY.
AND THE STUFF COMING OUT
OF ENCELADUS IS WATER
MIXED WITH OTHER STUFF.
YOU WOULDN'T WANT TO DRINK IT.
IT WOULD BE LIKE DRINKING
THE OCEAN WATER,
BUT IT'S MOSTLY WATER.
AND WHERE WE FIND WATER
AND ENERGY, THERE'S A CHANCE
THAT THERE MIGHT BE
SOMETHING ABLE TO SURVIVE
OR EVOLVE IN THERE.
Narrator: IT IS FULL OF SALTS
AND ORGANIC COMPOUNDS,
SOME OF THE KEY
BUILDING BLOCKS OF LIFE.
SO WE WONDER, COULD ENCELADUS
ALSO HAVE LIFE VERY SIMILAR
TO THE LIFE ON EARTH?
IS IT LIKE THE SAME KIND OF LIFE
WE HAVE HERE ON EARTH?
IS IT SOMETHING TOTALLY
DIFFERENT THAT WE CAN'T IMAGINE?
Narrator:
THE HUNT FOR VOLCANOES ELSEWHERE
CONTINUES TO PRODUCE
AMAZING BREAKTHROUGHS.
EVEN THE REMOTEST OF NEW SPACE
VOLCANOES CAN HAVE RELEVANCE
TO THE GEOLOGY OF EARTH.
**
AFTER A 9-YEAR ODYSSEY,
THE NEW HORIZONS PROBE
FINALLY REACHED
PLUTO IN JULY 2015.
WHAT IT DISCOVERED
WAS ASTONISHING.
Davies: THE NEW HORIZONS
SPACECRAFT THAT JUST VISITED
PLUTO FOUND FEATURES
THAT HAVE EVERY INDICATION
OF BEING CRYOVOLCANIC,
MOUNTAINS,
SHIELD-LIKE MOUNTAINS,
FLOWS ON THE SURFACE,
COMPLETELY UNEXPECTED AND JUST
AN EXTRAORDINARY DISCOVERY,
WHICH JUST SHOWS US
HOW EXCITING THE GAME CAN BE.
Narrator:
THIS IS WRIGHT MONS ON PLUTO.
AT 100 MILES ACROSS
AND 2 MILES HIGH,
IT'S BELIEVED TO BE
THE LARGEST CRYOVOLCANO
IN THE SOLAR SYSTEM.
IT'S DRIVEN BY A SIMILAR PROCESS
OF MOUNTAIN FORMATION
AS ON EARTH,
BUT INSTEAD OF MOLTEN ROCK,
IT'S BUILT UP FROM FLOWING ICE.
A RARE EVENT ON EARTH
CALLED FRAZIL ICE REVEALS
HOW FREEZING WATER CAN SOMETIMES
BEHAVE IN A SIMILAR WAY TO LAVA.
DURING WINTER, IT'S
OCCASIONALLY OBSERVED
IN YOSEMITE NATIONAL PARK.
A SLOWLY FLOWING RIVER
OF CHUNKS OF ICE,
GIVEN THE RIGHT CONDITIONS,
SUDDENLY FREEZES SOLID.
Gregg: WHAT HAPPENS WHEN WE SEE
FRAZIL ICE ON EARTH
IS IT IS SO CLOSE
TO ITS FREEZING POINT.
THAT'S WHY IT'S FILLED
WITH ICE CRYSTALS.
AND, IF IT COOLS
DOWN JUST ENOUGH,
SUDDENLY, ALL THE WATER
THAT'S LIQUID BETWEEN
THOSE ICE CRYSTALS FREEZES,
AND IT HAPPENS
JUST LIKE THAT.
AND IT'S ENTIRELY POSSIBLE
THAT THAT SAME PROCESS
COULD BE HAPPENING
ON THE SURFACE OF PLUTO.
**
Narrator: THE DISCOVERY OF ALL
THESE DIFFERENT SPACE VOLCANOES
HAS REVOLUTIONIZED OUR KNOWLEDGE
OF VULCANISM
THROUGHOUT THE SOLAR SYSTEM.
IT'S SO IMPORTANT TO STUDY
VULCANISM IN THE SOLAR SYSTEM
BECAUSE IT FILLS
IN THE MISSING PLACES
IN OUR THINKING ABOUT
HOW THIS WHOLE PROCESS WORKS.
Narrator: THE DISCOVERY
OF VOLCANOES ELSEWHERE
HAS MADE US LOOK AT EARTH
IN A NEW LIGHT.
IT'S VERY LIKELY THAT
WE CAN UNDERSTAND MORE ABOUT
WHAT MIGHT HAPPEN TO EARTH
IN THE FAR FUTURE.
WE CAN LOOK AT MARS AND VENUS,
FOR EXAMPLE,
SO WE CAN USE
THESE OTHER PLANETS
TO TEACH US ABOUT VULCANISM,
CLIMATE CHANGE AND OTHER
ASPECTS OF PLANETARY EVOLUTION.
Narrator: AND SPACE VOLCANOES
HAVE CHANGED
HOW WE SEARCH
FOR LIFE ELSEWHERE.
IN EXPLORING ENCELADUS,
IT'S VERY CLEAR
FROM WHAT WE'VE LEARNED
THAT WE NEED TO GO BACK
TO LEARN MORE.
IS THERE REALLY AND TRULY
LIFE ON ENCELADUS?
Narrator:
WHERE THERE'S VULCANISM,
THERE MIGHT BE LIFE.