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>>> PRESENTATION OF SCIENCE TREK 
ON IDAHO PUBLIC TELEVISION IS

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MADE POSSIBLE THROUGH THE 
GENEROUS SUPPORT OF THE LAURA

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MOORE CUNNINGHAM FOUNDATION, 
COMMITTED TO FULFILLING THE

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MOORE FAMILY LEGACY OF BUILDING 
THE GREAT STATE OF IDAHO.

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>>> THE EARTH IS OUR HOME, BUT 
IT'S MADE UP OF MANY COMPLEX

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SYSTEMS WORKING TOGETHER TO KEEP 
US ALIVE.

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FIND OUT MORE ABOUT THE EARTH.

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STAY TUNED.

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SCIENCE TREK IS NEXT.

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>>> HI, I'M JOAN CARTAN-HANSEN, 
AND WELCOME TO SCIENCE TREK, AND

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WELCOME TO BOISE STATE 
UNIVERSITY'S EARTH, SCIENCE,

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RESEARCH LAB.

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WE'RE HERE TO ANSWER YOUR 
QUESTIONS ABOUT THE EARTH, BUT

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BEFORE WE DO, LET'S LEARN A BIT 
MORE.

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>> LET'S SEE IF WE CAN KEEP IT 
UP IN THE AIR, AND WHO FOR THE

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LONGEST.

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>> OK.

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>> DID YOU KNOW THE EARTH IS 
93 MILLION MILES FROM THE SUN?

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THE EARTH IS THE THIRD PLANET 
FROM THE SUN.

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THE EARTH'S ORBIT IS MORE LIKE 
AN ELLIPSE RATHER THAN A PERFECT

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CIRCLE.

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THE EARTH SPINS ON AN AXIS, AND 
AN IMAGINARY LINE THAT GOES FROM

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POLE TO POLE.

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THE EARTH IS AT A TILT, IT'S THE 
TILT THAT GIVES US OUR SEASONS

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AS THE EARTH TRAVELS AROUND THE 
SUN.

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WHEN THE NORTHERN HEMISPHERE 
TILTS AWAY FROM THE SUN, YOU

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HAVE WINTER.

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AND AS THE NORTHERN HEMISPHERE 
TILTS TOWARDS THE SUN, WE GET

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SUMMER.

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AND BECAUSE THE EARTH IS 
SPINNING ON ITS AXIS, ONE SIDE

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OF THE PLANET FACES THE SUN AND 
THE OTHER IS IN THE SHAD OV,

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THAT'S WHAT GIVES US DAY AND 
NIGHT.

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>> DID YOU KNOW THAT OXYGEN ONLY 
MAKES UP 20% OF OUR AIR?

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>> THE EARTH IS COVERED BY A 
BLANKET OF GASES KNOWN AS THE

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SPHERE.

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THE TROPOSPHERE IS THE LOWEST 
LEVEL, THAT'S WHERE YOU WILL

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FIND THE AIR WE BREATHE.

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THE AIR IS 20% OXYGEN AND 70% 
NITROGEN, AND THE REST IS MADE

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UP OF OTHER GASES.

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ALL OF THE EARTH'S WEATHER 
HAPPENS IN THE TROPOSPHERE.

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THE NEXT LAYER IS THE 
STRATOSPHERE.

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THIS LAYER CONTAINS OZONE, A GAS 
THAT PROTECTS US FROM THE

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HARMFUL ULTRAVIOLET RAYS OF THE 
SUN.

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AFTER THAT, IS THE MESOSPHERE.

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THIS IS THE LAYER WHERE 
METEORITES USUALLY BURN UP FROM

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SPACE CREATING SHOOTING STARS.

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THEN THERE IS THE THERMO SPHERE, 
AND FINALLY THE EXOSPHERE.

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THIS IS THE OUTO MOST LAYER AT 
THE EDGE OF SPACE.

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>> LET ME PLAY!

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>> NO WAY.

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>> SO, DID YOU KNOW THAT THE 
EARTH'S CRUST IS ALWAYS MOVING?

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>> THE EARTH HAS FOUR MAIN 
LAYERS.

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AT THE CENTER IS AN EXTREMELY 
HOT CORE.

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THE CORE IS MADE UP OF TWO 
REGIONS.

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THE INNER CORE IS MADE UP OF 
SOLID, IRON, AND NICKEL.

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THE OUTER CORE IS MADE UP OF 
LIQUID IRON.

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THEY THINK THAT THE CIRCULATION 
OF THAT LIQUID CAUSES THE

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MAGNETIC FIELD AROUND THE EARTH.

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THE NEXT LAYER IS THE MANTLE, 
AND THEN THE OUTER LAYER, THE

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LAYER WE LIVE ON, IS KNOWN AS 
THE CRUST.

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THE CRUST IS ABOUT FOUR TO 
40 MILES THICK AND MAKES UP LESS

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THAN 1% OF THE EARTH'S MASS.

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IT'S BROKEN UP INTO PIECES KNOWN 
AS TECTONIC PLATES.

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TECTONIC PLATES ARE PUSHED AND 
PULLED AROUND BY THE SLOW AND

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STEADY MOVEMENT OF THE 
UNDERLYING ROCK.

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AS THE PLATES MOVE, STRESSES 
BUILD UP.

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EARTHQUAKES HAPPEN WHEN THE 
STRESSES GROW BIG ENOUGH THAT

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THE PLATES SLIDE PAST ONE 
ANOTHER QUICKLY, AND WE FEEL

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THAT SHAKING.

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MOST VOLCANOS APPEAR ALONG PLATE 
BOUNDARIES.

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LOTS OF THINGS CAN CHANGE THE 
EARTH'S SURFACE.

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SOME HAPPENS QUICKLY FROM STRONG 
THINGS LIKE EARTHQUAKES AND

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VOLCANOES.

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OTHERS HAPPEN OVER PERIODS OF 
TIME BECAUSE OF PROCESSES LIKE

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EROSION FROM WIND OR WATER.

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YOU CAN SEE PATTERNS IN ROCK 
FORMATIONS AND FOSSILS IN ROCK

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LAYERS THAT SHOW CHANGES IN THE 
EARTH'S SURFACE OVER TIME.

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HUMANS CHANGE THE LOOK OF 
EARTH'S SURFACE, TOO.

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BUILDINGS, FARMS, AND MINES ARE 
A FEW WAYS WE HAVE CHANGED THE

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LOOK OF THE EARTH.

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DID YOU KNOW THAT MOST OF THE 
EARTH'S SURFACE IS COVERED WITH

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WATER?

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>> 70% OF THE EARTH'S SURFACE IS 
COVERED BY OCEAN.

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ONLY .008% OF THE EARTH'S FRESH 
WATER IS FOUND IN LAKES, RIVERS,

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AND STREAMS.

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THAT'S THE WATER THAT WE NEED TO 
LIVE.

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SO, WHEN YOU THINK ABOUT THE 
EARTH, THINK ABOUT THE SYSTEMS

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THAT MAKE UP THE PLANET.

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THE GEOSPHERE, THE SOIL, 
SEDIMENTS AND SOLID AND MOLTEN

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ROCK.

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THE HYDROSPHERE, THE WATER ON 
EARTH.

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THE ATMOSPHERE, THE LEVELS OF 
AIR AND GASES AROUND THE EARTH,

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AND THE BIOSPHERE, ALL THE 
ECO-SYSTEMS AND LIVING THINGS ON

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EARTH.

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>> THAT'S A LOT TO THINK ABOUT.

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>> PLEASE LET ME PLAY!

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>> YOU WILL GET YOUR, GO AND GET 
YOUR OWN BALL.

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>> OK.

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YOU ARE GOING TO PLAY THAT LOOKS 
LIKE THIS, I AM GOING TO PLAY

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WITH ONE THAT LOOKS LIKE THE 
SUN.

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>> WHAT IS THAT ALL ABOUT?

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YOU KNOW.

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>> AND JOINING ME NOW TO ANSWER 
YOUR QUESTIONS ABOUT THE EARTH

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ARE VIRGINIA GILLERMAN, A 
GEOLOGIST WITH THE IDAHO

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GEOLOGICAL SURVEY, AND JEFFERY 
JOHNSON, ASSISTANT RESEARCH

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PROFESSOR OF GEOPHYSICS AT BOISE 
STATE UNIVERSITY.

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THANK YOU FOR JOINING US.

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>> THANK YOU VERY MUCH.

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>> THANK YOU.

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>> THIS IS GOING TO BE FUN.

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>> LET'S GO TO YOUR QUESTIONS.

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>> HI, MY NAME IS JEFF, AND I GO 
TO KAMIAH ELEMENTARY SCHOOL IN

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KAMIAH, IDAHO, AND MY QUESTION 
IS -- WHAT MAKES THE EARTH

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ROTATE?

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>> THE EARTH ROTATES BECAUSE 
IT'S ALWAYS ROTATED, AND THAT'S,

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THAT'S REALLY A PRETTY POOR 
ANSWER.

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BUT, IT IS INTERESTING TO NOTE 
THAT THE EARTH IS ROTATING ABOUT

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THE SAME RATE THAT IT IS NOW, AS 
IT DID WHEN THE EARTH FORMED

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4.6 BILLION YEARS AGO.

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THE FACT OF THE MATTER IS, IT'S 
SPINNING LIKE A TOP, AND THERE

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IS NOTHING OUT THERE, NO 
FRICTION THAT'S SLOWING IT DOWN,

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AND IT WILL CONTINUE TO SPIN 
UNTIL THE EARTH MAY BE BILLIONS,

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TRILLIONS OF YEARS FROM NOW, 
IMPACTS WITH ANOTHER BODY.

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>> HI, I AM BILLY, AND I AM FROM 
[INAUDIBLE] CHARTER SCHOOL, AND

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MY QUESTION IS -- WHAT ARE 
TECTONIC PLATES?

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>> TECTONIC PLATES, BILLY, ARE 
WHAT GEOLOGISTS CALL THE RIGID

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LAYERS OF ROCK, WHICH FLOAT ON A 
HOTTER AND MORE FLUID

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SEMI-LIQUID ROCK UNDERNEATH.

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THE TECTONIC PLATES ARE 
CONSTANTLY IN MOTION, AND WHEN

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ONE OF THEM DIVES UNDER THE 
OTHER, LIKE ON, ON THE, THE

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EASTERN, OR WESTERN COAST OF 
SOUTH AMERICA, THEY CAN FORM

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MOUNTAIN RANGES LIKE THE ANDES 
AND VOLCANOES LIKE ECUADOR OR

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SIMILAR THINGS ARE HAPPENING IN 
JAPAN.

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SO, IT'S, IT'S THE BOUNDARIES 
BETWEEN THESE TECTONIC PLATES

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THAT CREATES SOME OF OUR MOST 
INTERESTING GEOLOGY.

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>> AND ONE OF THE COOL THINGS 
ABOUT TECTONIC PLATES IS JUST

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HOW FAST THAT THEY MOVE.

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TECTONIC PLATES ARE MOVING 
CONSTANTLY, BUT YOU AND I, WE

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CANNOT FEEL THEM.

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THEY MOVE AT THE SAME SPEED AS 
YOUR FINGERNAILS GROW.

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>> JAMISON WOULD LIKE TO KNOW, 
HOW BIG IS THE EARTH?

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>> THE EARTH HAS A RADIUS OF 
6,371 KILOMETERS ON AVERAGE.

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THIS IS SOME 4,000 MILES IN 
TERMS OF THE RADIUS.

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HOW FAR IS THAT?

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THAT'S ABOUT THE DISTANCE FROM 
IDAHO TO NEW YORK AND BACK, AND

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SO IT'S A CONSIDERABLE SIZE.

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ONE THING THAT YOU MAY NOT BE 
AWARE OF IS THAT THE EARTH HAS A

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RADIUS THAT IS, THAT IS A LITTLE 
BIT BIGGER AT THE EQUATORS THAN

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AT THE POLES SO, OF THE EARTH AS 
BEING A SPHERE THAT'S SLIGHTLY

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SQUASHED.

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>> I AM ADDISON, AND MY QUESTION 
IS, WILL THE EARTH CONTINENTS

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EVER MEET AGAIN?

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>> THE EDGES OF THE CONTINENTS 
MEET, THEY MEET THE OCEAN

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PLATES, AND SOMETIMES, THEY MEET 
OTHER CONTINENTAL PLATES LIKE IN

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THE HIMALAYAS, BUT OVER THE LAST 
COUPLE OF BILLION YEARS,

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GEOLOGISTS ARE FINDING OUT, THE 
EARTH'S CONTINENTS AND PLATES

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HAVE MOVED TOGETHER AND THEN 
BEEN DRIVEN APART SEVERAL TIMES.

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SO, WE FORMED SUPER CONTINENTS 
LIKE RODINIA AND PANCIA, WHERE

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THE CONTINENTAL MASSES, THE LAND 
THAT YOU SEE THAT HAS ROCKS THAT

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HAVE MORE SILICON AND ALUMINUM 
AND SANDSTONE AREAS, THOSE

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CONTINENTAL AREAS HAVE BEEN 
PUSHED TOGETHER INTO THE SUPER

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COULD NOT NENTSZ, AND OVER TIME 
THOSE WILL BREAK APART AGAIN,

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SORT OF LIKE BILLIARD BALLS, YOU 
KNOW.

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HITTING EACH OTHER AND THEN 
BOUNCING OFF EACH OTHER.

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SO, THEY WILL MEET AGAIN, AND 
THEY WILL BREAK APART AGAIN.

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IT MAY TAKE A FEW MILLION YEARS.

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>> AND IN INDIA AND ASIA RIGHT 
NOW ARE COLLIDING WITH ONE

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ANOTHER, BUT IT'S A SLOW MOTION 
COLLISION.

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THOSE TWO CONTINENTS ARE COMING 
TOGETHER AT A RATE OF ONLY A FEW

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INCHES A YEAR, AND THEY ARE 
CAUSING THE CONTINUING UPLIFT IN

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GROWTH OF THE HIMALAYA 
MOUNTAINS.

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>> HARRIS WOULD LIKE TO KNOW, 
HOW WAS THE EARTH FORMED?

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>> HARRIS, THE EARTH WAS FORMED 
A LONG, LONG TIME AGO,

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4.6 BILLION YEARS AGO, THE EARTH 
ACCUMULATED FROM INTERSTELLAR

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GASES AND DEBRIS AND ACCUMULATED 
AND GREW INTO THE BLOB THAT WE

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LIVE ON TODAY.

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>> ALLEY WOULD LIKE TO KNOW, HOW 
DID GRAVITY GET TO EARTH AND WHO

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OR WHAT CREATED IT?

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>> GRAVITY IS A FUNDAMENTAL 
FORCE THAT EXISTS ANY TIME THAT

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YOU HAVE MASS.

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SO, WE HAVE GRAVITY ASSOCIATED 
WITH OUR OWN HUMAN BODIES, BUT

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THE EARTH'S MASS IS SO MUCH 
LARGER, THAT THE GRAVITATIONAL

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00:10:07,907 --> 00:10:09,642
FORCE IS VERY MUCH NOTICEABLE.

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00:10:09,642 --> 00:10:12,979
THIS IS WHY WE DON'T FLOAT OFF 
INTO SPACE.

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00:10:12,979 --> 00:10:18,084
SO, WE HAVE GRAVITY BECAUSE THE 
EARTH IS VERY BIG AND MASSIVE.

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00:10:18,084 --> 00:10:20,987
OTHER PLANETS ALSO HAVE GRAVITY, 
AND GRAVITY CAN EITHER BE

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GREATER OR SMALLER, DEPENDING 
UPON HOW BIG THE PLANETS ARE.

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SO, IF YOU LIVE ON ANOTHER 
PLANET THAT'S BIGGER, YOU WILL

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HAVE A GREATER FORCE OF GRAVITY, 
AND YOU WILL WEIGH HEAVIER.

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00:10:32,032 --> 00:10:37,037
>> HI, I'M KELLEN, AND MY 
QUESTION IS -- WHAT PURPOSE DO

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THE LAYERS OF THE ATMOSPHERE 
SERVE?

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>> WELL, KELLEN, THE ATMOSPHERE 
IS REALLY CRITICAL FOR US HUMAN

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BEINGS BECAUSE IT PROVIDES THE 
OXYGEN THAT WE NEED TO BREATHE

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AND TO LIVE FROM, AND IT ALSO 
PROVIDES CARBON DIOXIDE, WHICH

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PLANTS BREATHE AND USE IN PHOTO 
SYNTHESIS, AND IT HAS OZONE,

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THAT HELP TO PROTECT US FROM THE 
SUN'S HARMFUL RADIATION.

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SO, WE WOULD NOT BE HERE WITHOUT 
THE ATMOSPHERE.

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00:11:08,268 --> 00:11:11,237
>> I WAS GOING TO ADD THAT THE 
WEATHER IS HAPPENING IN OUR

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00:11:11,237 --> 00:11:12,072
ATMOSPHERE, AS WELL.

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>> WEATHER, OF COURSE.

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THAT'S A REALLY IMPORTANT 
FUNCTION.

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>> YOU MAY FEEL LIKE YOU ARE 
STANDING STILL, BUT AS THE EARTH

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SPINS, YOU ARE MOVING FAST, 
DEPENDING ON WHERE YOU ARE ON

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00:11:27,253 --> 00:11:30,256
THE GLOBE, YOU COULD BE SPINNING 
AT OVER 1,000 MILES PER HOUR,

205
00:11:30,256 --> 00:11:33,727
AND WE ALL TRAVEL AT 67,000 
MILES PER HOUR AS THE EARTH

206
00:11:33,727 --> 00:11:40,934
MOVES AROUND THE SUN.

207
00:11:40,934 --> 00:11:45,005
>> HI, MY NAME IS ZOE, AND MY 
QUESTION IS -- HOW DOES THE

208
00:11:45,005 --> 00:11:47,540
EARTH'S ATMOSPHERE COMPARE TO 
OTHER PLANETS?

209
00:11:47,540 --> 00:11:50,577
>> EARTH'S ATMOSPHERE IS THE 
BEST ATMOSPHERE THAT WE KNOW OF

210
00:11:50,577 --> 00:11:52,679
FOR SUSTAINING LIFE.

211
00:11:52,679 --> 00:11:56,383
NOW, OTHER PLANETS WITHIN OUR 
SOLAR SYSTEM ALSO HAVE

212
00:11:56,383 --> 00:11:56,850
ATMOSPHERES.

213
00:11:56,850 --> 00:11:59,219
MOST OF THEM ARE MUCH, MUCH 
THINNER THAN THE EARTH'S

214
00:11:59,219 --> 00:12:01,988
ATMOSPHERE, AND NONE OF THEM 
HAVE OXYGEN, WHICH IS NECESSARY

215
00:12:01,988 --> 00:12:03,723
FOR LIFE.

216
00:12:03,723 --> 00:12:07,894
ONE OF THE SOLAR SYSTEMS PLANETS 
THAT HAS A THICK ATMOSPHERE IS

217
00:12:07,894 --> 00:12:11,598
VENUS, AND VENUS HAS LOTS AND 
LOTS OF CARBON DIOXIDE, AND AS

218
00:12:11,598 --> 00:12:16,436
FAR AS WE KNOW, THIS IS NOT A 
GAS THAT'S VERY GOOD FOR MOST

219
00:12:16,436 --> 00:12:20,273
TYPES OF LIFE FORMS.

220
00:12:20,273 --> 00:12:24,277
>> KYLE WOULD LIKE TO KNOW IS IT 
POSSIBLE TO LIVE ON ANOTHER

221
00:12:24,277 --> 00:12:24,744
PLANET?

222
00:12:24,744 --> 00:12:27,881
>> IT'S NOT POSSIBLE FOR HUMANS, 
LIKE WE ARE, TO LIVE ON ANY OF

223
00:12:27,881 --> 00:12:30,283
THE OTHER PLANETS THAT WE KNOW 
ABOUT.

224
00:12:30,283 --> 00:12:32,185
CERTAINLY NOT IN THIS SOLAR 
SYSTEM.

225
00:12:32,185 --> 00:12:35,822
THEY DON'T HAVE THE RIGHT AMOUNT 
OF OXYGEN IN THE ATMOSPHERE.

226
00:12:35,822 --> 00:12:37,557
SOME OF THEM ARE WAY TOO HOT.

227
00:12:37,557 --> 00:12:39,726
SEVERAL HUNDRED DEGREES EVERY 
DAY.

228
00:12:39,726 --> 00:12:41,561
OR WAY TOO COLD.

229
00:12:41,561 --> 00:12:46,733
AND, AND OUR LIFE, OUR, OUR 
HUMANS AND OUR ANIMALS AND OUR

230
00:12:46,733 --> 00:12:51,671
PLANTS HAVE EVOLVED UNDER THE 
SPECIAL CIRCUMSTANCES ON EARTH.

231
00:12:51,671 --> 00:12:56,576
SO, WITHOUT EXTRAORDINARY 
MEASURES AS IN A SPACE STATION

232
00:12:56,576 --> 00:12:59,212
OR SUITS, WE CANNOT LIVE ON 
OTHER PLANETS IN THE SOLAR

233
00:12:59,212 --> 00:13:01,047
SYSTEM.

234
00:13:01,047 --> 00:13:07,320
>> I AM INDY, AND MY QUESTION IS 
-- HOW DOES THE ATMOSPHERE KEEP

235
00:13:07,320 --> 00:13:08,688
IN OXYGEN?

236
00:13:08,688 --> 00:13:14,094
>> WELL, INDY, THE SPHERE HAS A 
VERY IMPORTANT ROLE IN KEEPING

237
00:13:14,094 --> 00:13:17,063
IN THE OXYGEN.

238
00:13:17,063 --> 00:13:21,701
SOME OF THAT IS DUE TO CARBON 
DIOXIDE AND OTHER GASES IN THE

239
00:13:21,701 --> 00:13:22,268
ATMOSPHERE.

240
00:13:22,268 --> 00:13:24,904
AND, AND I BELIEVE THAT SOME OF 
IT IS SIMPLY DUE TO GRAVITY

241
00:13:24,904 --> 00:13:29,442
BECAUSE GRAVITY STILL WOULD 
EXERT SOME PULL ON, ON EVEN

242
00:13:29,442 --> 00:13:32,178
GASES, IS THAT CORRECT, JEFF?

243
00:13:32,178 --> 00:13:34,981
>> GRAVITY, ULTIMATELY, KEEPS 
THE ATMOSPHERE NEXT TO THE

244
00:13:34,981 --> 00:13:39,085
EARTH, BUT, IT'S IMPORTANT TO 
NOTE THAT WE ARE LOSING OXYGEN

245
00:13:39,085 --> 00:13:42,822
TO, TO, DUE TO, DUE TO TRAVEL 
OUTSIDE OF OUR ATMOSPHERE.

246
00:13:42,822 --> 00:13:46,659
AND, AND AS WELL AS BY 
ABSORPTION OF OXYGEN IN OUR

247
00:13:46,659 --> 00:13:47,193
ROCKS.

248
00:13:47,193 --> 00:13:51,464
SO, THERE IS A CONSTANT BALANCE 
BETWEEN PRODUCTION OF OXYGEN

249
00:13:51,464 --> 00:13:58,038
FROM PLANTS AND LOSS OF OXYGEN 
DUE TO ESCAPE FROM THE PLANET,

250
00:13:58,038 --> 00:14:01,708
AS WELL AS THE PROCESSES WHICH 
LOCK UP THAT OXYGEN IN OUR

251
00:14:01,708 --> 00:14:02,208
ROCKS.

252
00:14:02,208 --> 00:14:02,976
>> AND HI.

253
00:14:02,976 --> 00:14:07,147
MY NAME IS CHLOE, AND I GO TO 
HILLCREST ELEMENTARY SCHOOL.

254
00:14:07,147 --> 00:14:10,250
HOW DOES THE VOLCANO SHOOT OUT 
LAVA?

255
00:14:10,250 --> 00:14:11,885
>> OH, I GET THIS ONE, CHLOE.

256
00:14:11,885 --> 00:14:16,256
I LOVE TO STUDY VOLCANOES, AND I 
STUDY HOW VOLCANOES PRODUCE LAVA

257
00:14:16,256 --> 00:14:20,093
AND HOW THAT LAVA GETS EJECTED 
FROM A VOLCANIC VENT.

258
00:14:20,093 --> 00:14:24,531
SO, REALLY, THERE IS ONE QUICK 
ANSWER, AND THAT IS VOLCANIC

259
00:14:24,531 --> 00:14:29,069
GASES DRIVE EXPLOSIONS, AND 
THOSE GASES CAN BE STEAM, CARBON

260
00:14:29,069 --> 00:14:32,706
DIOXIDE, OR SULFUR DIOXIDE, BUT 
PRESSURIZED GASES BLOW MATERIAL

261
00:14:32,706 --> 00:14:36,276
OUT OF A VOLCANIC VENT WITH MORE 
ENERGY AND MORE POWER THAN YOU

262
00:14:36,276 --> 00:14:38,244
CAN EVEN IMAGINE.

263
00:14:38,244 --> 00:14:44,718
>> MY NAME IS SOPHIE AND MY 
QUESTION IS, HOW DO HOT SPOTS

264
00:14:44,718 --> 00:14:45,285
MOVE?

265
00:14:45,285 --> 00:14:48,288
>> SOPHIE HOT SPOTS DON'T REALLY 
MOVE.

266
00:14:48,288 --> 00:14:53,026
IT'S, ACTUALLY, THE TECTONIC 
PLATES THAT MOVE OVER THE HOT

267
00:14:53,026 --> 00:14:56,262
SPOTS, SO A HOT SPOT LOOKS LIKE 
A PENCIL, THAT EXTENDS DEEP INTO

268
00:14:56,262 --> 00:14:57,030
THE EARTH.

269
00:14:57,030 --> 00:15:02,769
AND AS THE PLATE MOVES OVER IT, 
IT CREATES AN APPARENT HOT SPOT

270
00:15:02,769 --> 00:15:03,236
TRACK.

271
00:15:03,236 --> 00:15:09,609
AND FOR EXAMPLE, THE YELLOWSTONE 
HOT SPOT IS CURRENTLY UNDER

272
00:15:09,609 --> 00:15:11,611
YELLOWSTONE NATIONAL PARK.

273
00:15:11,611 --> 00:15:14,314
BUT 15 MILLION YEARS AGO, THE 
CONTINENT WAS SITUATED SUCH THAT

274
00:15:14,314 --> 00:15:18,585
HOT SPOT WAS ABOUT WHERE THE 
JUNCTION OF OREGON, IDAHO, AND

275
00:15:18,585 --> 00:15:20,520
NEVADA IS, IS TODAY.

276
00:15:20,520 --> 00:15:24,691
WE CAN TRACK THE MOVEMENT OF THE 
PLATE OVER THAT HOT SPOT BY

277
00:15:24,691 --> 00:15:29,262
LOOKING AT AGES OF ROCKS, THE 
PARTICULAR TYPE OF VOLCANIC

278
00:15:29,262 --> 00:15:33,066
ROCK, ALONG THAT, THAT, THAT HOT 
SPOT TRACK.

279
00:15:33,066 --> 00:15:39,739
>> HI, I AM OSCAR, AND I WAS 
WONDERING HOW COME YELLOWSTONE

280
00:15:39,739 --> 00:15:43,610
IS SO GEE LOGICALLY ACTIVE AND 
WHY THERE IS NO OTHER PLACE IN

281
00:15:43,610 --> 00:15:45,345
THE WORLD LIKE IT.

282
00:15:45,345 --> 00:15:48,448
>> YELLOWSTONE IS VERY ACTIVE.

283
00:15:48,448 --> 00:15:51,718
WE THINK IT'S ACTIVE BECAUSE WE 
CAN SEE IT TODAY.

284
00:15:51,718 --> 00:15:55,722
BUT, THERE ARE OTHER PLACES IN 
THE EARTH THAT ARE SIMILAR TO

285
00:15:55,722 --> 00:16:01,294
YELLOWSTONE THAT HAVE SIMILAR 
ROCKS, FOR EXAMPLE, THE, THE

286
00:16:01,294 --> 00:16:08,868
VOLCANIC ZONE IN NEW ZEALAND, 
WHICH IS ALSO UNDER LANE BY WHAT

287
00:16:08,868 --> 00:16:12,572
GEOLOGISTS WHERE THERE IS A 
LARGE MASS OF LIQUID ROCK OR

288
00:16:12,572 --> 00:16:16,976
MAGMA THAT IS HIGH IN SILICON 
AND ALUMINUM.

289
00:16:16,976 --> 00:16:21,881
AND, AND IN THAT CASE, ALSO, 
LIKE YELLOWSTONE, THE, THE HOT

290
00:16:21,881 --> 00:16:26,319
MAGMA CHAMBER HAS HEATED THE 
GROUNDWATER AND PRODUCED

291
00:16:26,319 --> 00:16:30,323
GEYSERS, HOT POOLS, MUD POTS, 
AND SIMILAR FEATURES THAT IF YOU

292
00:16:30,323 --> 00:16:34,794
VISIT NEW ZEALAND, YOU CAN WALK 
THROUGH.

293
00:16:34,794 --> 00:16:41,267
SO, YELLOWSTONE IS ONE OF THE 
PLACES THAT IS VOLCANOICALLY AND

294
00:16:41,267 --> 00:16:43,436
GEOTHEY REMEMBERALLY ACTIVE 
RIGHT NOW.

295
00:16:43,436 --> 00:16:45,605
THERE HAVE BEEN OTHER PLACES 
LIKE IT IN THE PAST, AND THERE

296
00:16:45,605 --> 00:16:50,610
IS A FEW OTHER PLACES LIKE IT IN 
THE WORLD TODAY.

297
00:16:50,610 --> 00:16:54,914
>> I JUST LIKE TO ADD THAT 
YELLOWSTONE IS SPECIAL IN THAT

298
00:16:54,914 --> 00:16:58,018
IT HAS THE MOST GEYSERS IN THE 
ENTIRE WORLD.

299
00:16:58,018 --> 00:17:02,956
IN FACT, 50% OF EARTH'S GEYSERS 
HAPPEN TO BE IN YELLOWSTONE.

300
00:17:02,956 --> 00:17:04,024
IT IS WONDERFUL.

301
00:17:04,024 --> 00:17:06,860
IT'S IN OUR BACKYARD, AND I AM 
VERY PROUD TO BE LIVING NOT SO

302
00:17:06,860 --> 00:17:14,567
FAR AWAY FROM YELLOWSTONE.

303
00:17:14,567 --> 00:17:17,604
>> THE FIELD OF STUDY THAT DEALS 
WITH THE REPRESENTATION AND

304
00:17:17,604 --> 00:17:21,975
MEASUREMENT OF THE EARTH IS 
GEOCITY.

305
00:17:21,975 --> 00:17:24,077
IT IS A SCIENCE THAT GOES WAY 
BACK.

306
00:17:24,077 --> 00:17:29,315
>> A LONG TIME AGO IN EGYPT, A 
MAN FIGURE OUT WHEN THE SUN WAS

307
00:17:29,315 --> 00:17:32,619
ABOVE ONE CITY, YOU COULD STAND 
AT A NEARBY CITY TO THE NORTH

308
00:17:32,619 --> 00:17:37,257
AND MEASURE THE ANGLE OF THE 
SHADOW SAYS AND MULTIPLY THAT BY

309
00:17:37,257 --> 00:17:39,626
THE DISTANCE TO GET THE DISTANCE 
AROUND THE ENTIRE EARTH.

310
00:17:39,626 --> 00:17:43,530
WITH THAT, THE SCIENCE OF 
GEODESY WAS BORN.

311
00:17:43,530 --> 00:17:45,899
IT DEALS WITH THE MEASUREMENT 
AND REPRESENTATION OF THE EARTH,

312
00:17:45,899 --> 00:17:49,336
OR TO PUT IT MORE SIMPLY, THE 
SCIENCE OF WHERE THINGS ARE AND

313
00:17:49,336 --> 00:17:51,971
JUST AS IMPORTANTLY, WHERE THEY 
HAVE BEEN AND WHERE THEY ARE

314
00:17:51,971 --> 00:17:53,006
GOING.

315
00:17:53,006 --> 00:17:56,443
6 THROUGH GEODESY, WE LEARN THE 
SIZE AND SHAPE OF THE EARTH, THE

316
00:17:56,443 --> 00:18:00,113
DIRECTION OF THE ROTATION, AND 
THE DISTANCE FROM THE SUN, AND

317
00:18:00,113 --> 00:18:02,315
MORE.

318
00:18:02,315 --> 00:18:05,752
WE THROUGH TRIANGULATION, WE CAN 
CREATE MAPS OF COUNTRIES, AND

319
00:18:05,752 --> 00:18:08,321
EVEN FIGURED OUT THE EARTH IS 
NOT A PERFECT SPHERE, AND AFTER

320
00:18:08,321 --> 00:18:11,958
SOME ARGUMENTS AND EXPEDITIONS 
TO PERU, WE MEASURED THAT IT'S

321
00:18:11,958 --> 00:18:13,927
JUST A BIT THICKER IN THE 
MIDDLE.

322
00:18:13,927 --> 00:18:18,498
BUILDING ON THIS INFORMATION, WE 
FOUND TONS OF PRACTICAL USES FOR

323
00:18:18,498 --> 00:18:19,032
GEODESY.

324
00:18:19,032 --> 00:18:22,502
USUALLY STARS AS A REFERENCE 
POINT, AND ACCURATE WATCHES, WE

325
00:18:22,502 --> 00:18:25,772
COULD RELIABLY DETERMINE 
LATITUDE AND LONGITUDE SO SHIPS

326
00:18:25,772 --> 00:18:27,774
COULD CROSS OCEANS TO GET TO 
WHERE THEY NEEDED.

327
00:18:27,774 --> 00:18:30,243
THE EXPLORERS VISITED 
UNCHARTERED REGIONS, AND MAPPED

328
00:18:30,243 --> 00:18:33,246
THEM AND FOUND THE TALLEST 
MOUNTAIN IN THE WORLD.

329
00:18:33,246 --> 00:18:37,584
LATER, ENGINEERS BUILT RAILROADS 
TO GET US TO THESE PLACES.

330
00:18:37,584 --> 00:18:40,687
WITH THE SAME REFERENCE SURFACE, 
RAIL TUNNELS COULD BE STARTED ON

331
00:18:40,687 --> 00:18:45,058
BOTH SIDES OF THE MOUNTAIN, AND 
SOMEHOW MEET IN THE MIDDLE.

332
00:18:45,058 --> 00:18:45,892
LIFE WAS GOOD.

333
00:18:45,892 --> 00:18:48,695
ONCE WE INVENTED RADIO 
TELESCOPES AND SATELLITES,

334
00:18:48,695 --> 00:18:49,629
THINGS GOT EVEN BETTER.

335
00:18:49,629 --> 00:18:52,632
WHEN SCIENTISTS USED A BUNCH OF 
SMALL RADIO DISHES LIKE ONE BIG

336
00:18:52,632 --> 00:18:56,870
ONE TO LOOK, SOMEBODY GOT THE 
IDEA YOU COULD USE THESE

337
00:18:56,870 --> 00:18:59,572
MEASUREMENTS TO DETERMINE VERY 
ACCURATELY THE DISTANCE BETWEEN

338
00:18:59,572 --> 00:19:03,376
THE TELESCOPES, AND NOW WE CAN 
LOOK AT THE MOVEMENT OF THE

339
00:19:03,376 --> 00:19:08,014
EARTH'S CHANGES, AND HOW THE 
EARTH TRAVELS ON ITS AXIS.

340
00:19:08,014 --> 00:19:10,450
SATELLITES BECAME VERY IMPORTANT 
BY ANALYZING THEIR ORBITS, WE

341
00:19:10,450 --> 00:19:14,554
CAN LEARN ABOUT OUR PLANET'S 
CHANGING SIZE AND SHAPE AND

342
00:19:14,554 --> 00:19:18,458
GRAVITY, AND BY MAKING LASER 
MEASUREMENTS, WE CAN LOOK AT

343
00:19:18,458 --> 00:19:21,461
CHANGES IN THE HEIGHT OF THE 
OCEANS AND ICE SHEETS TO HOW THE

344
00:19:21,461 --> 00:19:29,936
TIETH -- TIETS -- TIDES WORK, IS 
A GEODESY HAS A HUGE IMPACT ON

345
00:19:29,936 --> 00:19:32,405
OUR LIVES AND ALL BECAUSE 
SOMEBODY A LONG TIME AGO DECIDED

346
00:19:32,405 --> 00:19:38,778
TO LOOK DOWN A WELL.

347
00:19:38,778 --> 00:19:43,683
>> I AM FENA, AND MY QUESTION IS 
-- WHY WAS THERE VOLCANIC

348
00:19:43,683 --> 00:19:47,420
ACTIVITY IN IDAHO'S GEOLOGIC 
HISTORY BUT THERE ARE NOT ANY

349
00:19:47,420 --> 00:19:48,988
VOLCANOES IN IDAHO NOW?

350
00:19:48,988 --> 00:19:53,326
>> THERE HAVE BEEN PERIODS IN 
THE PAST, NOTABLY, ABOUT

351
00:19:53,326 --> 00:19:58,732
2 MILLION YEARS AGO, WHEN THE 
VOLCANOES OF THE SNAKE RIVER

352
00:19:58,732 --> 00:20:01,534
PLAIN WERE POPPING UP ALL OVER 
THE PLACE.

353
00:20:01,534 --> 00:20:06,706
15 MILLION YEARS AGO, WHEN THE 
COLUMBIA RIVER, BASALTS POURED

354
00:20:06,706 --> 00:20:09,642
OUT AND FLOWED TO THE PACIFIC 
OCEAN, AND ABOUT 45 MILLION

355
00:20:09,642 --> 00:20:14,547
YEARS AGO, WHEN THE CHALLIS 
VOLCANIC EPISODE OCCURRED.

356
00:20:14,547 --> 00:20:18,084
SO, THERE'S BEEN TIMES WHEN IT'S 
BEEN MUCH MORE ACTIVE THAN IT IS

357
00:20:18,084 --> 00:20:19,719
RIGHT NOW.

358
00:20:19,719 --> 00:20:20,820
BUT, YOU NEVER KNOW.

359
00:20:20,820 --> 00:20:24,524
MAYBE WE'LL GET A, A BIG 
VOLCANIC ERUPTION TOMORROW.

360
00:20:24,524 --> 00:20:28,194
>> YOU KNOW, I WOULD NOT LOSE 
SLEEP OVER THE IDEA OF A BIG

361
00:20:28,194 --> 00:20:29,662
VOLCANIC ERUPTION TOMORROW.

362
00:20:29,662 --> 00:20:34,100
BUT, IT IS IMPORTANT TO NOTE 
THAT IDAHO DOES HAVE RECENT

363
00:20:34,100 --> 00:20:38,004
VOLCANIC ACTIVITY, AS EARLY AS, 
AS RECENT AS 2000 YEARS AGO,

364
00:20:38,004 --> 00:20:42,042
THERE WERE LAVAS THAT ERUPTED 
FROM CRATERS OF THE MOON

365
00:20:42,042 --> 00:20:45,745
NATIONAL MONUMENT THAT HAS VERY, 
VERY FRESH LAVA FLOWS.

366
00:20:45,745 --> 00:20:49,916
AND 2000 YEARS AGO IS REALLY A 
BLINK OF THE EYE IN TERMS OF THE

367
00:20:49,916 --> 00:20:52,485
GEOLOGIC HISTORY.

368
00:20:52,485 --> 00:20:55,855
>> GABBY WOULD LIKE TO KNOW HOW 
DO WE GET EARTHQUAKES?

369
00:20:55,855 --> 00:20:59,526
>> EARTHQUAKES HAPPEN WHEN ROCKS 
BREAK VERY, VERY QUICKLY.

370
00:20:59,526 --> 00:21:03,630
WHEN THAT HAPPENS, THE EARTH 
MOVES VERY RAPIDLY, AND

371
00:21:03,630 --> 00:21:07,100
GENERATES SEISMIC WAVES, WHICH 
WE CAN RECORD WITH, WITH

372
00:21:07,100 --> 00:21:13,073
DELICATE AND HIGH FIDELITY 
INSTRUMENTATION CALLED

373
00:21:13,073 --> 00:21:13,606
SIZEOMETERS.

374
00:21:13,606 --> 00:21:15,542
THAT IS NOTHING MORE THAN AN 
INSTRUMENT THAT RECORDS THE

375
00:21:15,542 --> 00:21:20,447
SHAKING OF THE GROUND WITH MUCH 
MORE SENSITIVITY THAN HUMANS

376
00:21:20,447 --> 00:21:20,814
CAN.

377
00:21:20,814 --> 00:21:26,619
>> I AM AALIYAH AND I HAVE A 
QUESTION, WHY DOES CALIFORNIA

378
00:21:26,619 --> 00:21:28,822
HAVE SO MANY EARTHQUAKES AND 
IDAHO HAS SO FEW.

379
00:21:28,822 --> 00:21:31,891
>> YOU ARE ASKING WHY DOES IDAHO 
NOT HAVE MANNY EARTHQUAKES AS

380
00:21:31,891 --> 00:21:32,525
CALIFORNIA.

381
00:21:32,525 --> 00:21:37,297
IT'S FOR THE SIMPLE REASON THAT 
IDAHO IS LOCATED IN THE INTERIOR

382
00:21:37,297 --> 00:21:39,366
OF A CONTINENT.

383
00:21:39,366 --> 00:21:43,103
CALIFORNIA IS RIGHT ON THE VERY 
EDGE OF WHERE NORTH AMERICA AND

384
00:21:43,103 --> 00:21:44,738
PACIFIC TECTONIC PLATES MEET.

385
00:21:44,738 --> 00:21:48,742
AND IT JUST SO HAPPENS THAT MOST 
OF EARTH'S EARTHQUAKES HAPPEN

386
00:21:48,742 --> 00:21:50,310
ALONG THESE BOUNDARIES.

387
00:21:50,310 --> 00:21:55,048
THAT IS NOT TO SAY THAT IDAHO 
DOESN'T HAVE ANY EARTHQUAKES OR

388
00:21:55,048 --> 00:21:57,550
WON'T HAVE EARTHQUAKES IN THE 
FUTURE, BUT THE NUMBER OF

389
00:21:57,550 --> 00:22:01,888
EARTHQUAKES IN IDAHO IS FAR LESS 
THAN IT IS IN, SAY, CALIFORNIA,

390
00:22:01,888 --> 00:22:05,325
AND THE SIZE OF THE EARTHQUAKES 
THAT OCCUR HERE, ARE GENERALLY

391
00:22:05,325 --> 00:22:06,326
MUCH SMALLER.

392
00:22:06,326 --> 00:22:10,363
THE MOST RECENT, LARGEST 
EARTHQUAKES TO HAVE OCCURRED IN

393
00:22:10,363 --> 00:22:14,000
IDAHO HAPPENED IN 1983.

394
00:22:14,000 --> 00:22:16,970
AND IT WAS A MAGNITUDE OF 7.3 
EARTHQUAKE.

395
00:22:16,970 --> 00:22:21,274
BUT THEY HAPPEN VERY 
INFREQUENTLY.

396
00:22:21,274 --> 00:22:25,912
>> CARA ASKS, WHY DOES THE EARTH 
MOVE BUT WE DON'T FEEL IT MOVE?

397
00:22:25,912 --> 00:22:30,116
>> THE EARTH MOVES, AND IT MOVES 
OVER ALL SORTS OF TIME SCALES,

398
00:22:30,116 --> 00:22:33,653
AND IT MOVES IN VERY INTERESTING 
FASHIONS.

399
00:22:33,653 --> 00:22:37,023
WE DO EXPERIENCE EARTH MOVEMENTS 
WHEN EARTHQUAKES OCCUR, AND THAT

400
00:22:37,023 --> 00:22:41,928
IS WHEN, WHEN SUDDEN BREAKAGE OF 
ROCKS CAUSE A SEISMIC WAVE TO

401
00:22:41,928 --> 00:22:47,934
PROPGATE AND SHAKE IT, BUILDINGS 
CAN BE KNOCKED OVER, AND THOSE

402
00:22:47,934 --> 00:22:49,736
MOVEMENTS CAN BE VERY, VERY 
INTENSE.

403
00:22:49,736 --> 00:22:55,308
NOW, THE EARTH ALSO MOVES VERY 
SLOWLY DUE TO PLATE TECTONIC

404
00:22:55,308 --> 00:22:55,675
MOVEMENTS.

405
00:22:55,675 --> 00:22:59,579
THOSE MOVEMENTS ARE SO VERY 
SLOW, THAT MOST OF US WILL NEVER

406
00:22:59,579 --> 00:23:00,613
SENSE THEM.

407
00:23:00,613 --> 00:23:05,051
THOSE PLATE TECTONIC MOVEMENTS 
OCCUR AT RATES OF ONLY A FEW

408
00:23:05,051 --> 00:23:06,486
INCHES PER YEAR.

409
00:23:06,486 --> 00:23:08,688
VERY, VERY SLOW.

410
00:23:08,688 --> 00:23:12,792
>> AND, OF COURSE, THE EARTH IS 
MOVING, SIMPLY BY ROTATING EACH

411
00:23:12,792 --> 00:23:13,526
DAY.

412
00:23:13,526 --> 00:23:18,164
BUT, IT HAPPENS ON SUCH A LARGE 
MASS, AND AT SUCH A, A SLOW RATE

413
00:23:18,164 --> 00:23:20,900
THAT WE DON'T FEEL IT.

414
00:23:20,900 --> 00:23:25,905
>> HI, I AM JENNA, AND I AM PART 
OF ANSWER -- ANTHONY CHARTER

415
00:23:25,905 --> 00:23:29,242
SCHOOL, AND MY QUESTION IS WHY 
IS THE SKY BLUE?

416
00:23:29,242 --> 00:23:32,012
>> THE SKY IS THE BLUE BECAUSE 
THE SUN WHEN RADIATES OUR

417
00:23:32,012 --> 00:23:36,349
SUNLIGHT IN THE FORM OF LIGHT, 
WHICH COMPRISES ALL COLORS OF

418
00:23:36,349 --> 00:23:41,087
THE RAINBOW, INTERACTS WITH THE 
SPHERE.

419
00:23:41,087 --> 00:23:44,524
OUR ATMOSPHERE HAS OXYGEN IN IT 
WHEN SCATTERS THE BLUE PORTION

420
00:23:44,524 --> 00:23:48,261
OF THE VISIBLE LIGHT, AND THAT 
THAT SCATTERED ENERGY COMES

421
00:23:48,261 --> 00:23:50,897
DOWN, AND WE CAN SEE IT WITH OUR 
EYES.

422
00:23:50,897 --> 00:23:55,201
IF YOU WERE TO LOOK AT THE SUN 
OUTSIDE OF THE SPHERE, IT WOULD

423
00:23:55,201 --> 00:23:56,636
LOOK WHITE.

424
00:23:56,636 --> 00:23:59,939
>> DEVON ASKS, HOW DID THE EARTH 
GET ITS NAME?

425
00:23:59,939 --> 00:24:02,308
>> I HAD TO LOOK THIS ONE UP.

426
00:24:02,308 --> 00:24:08,415
AND FROM WHAT I COULD READ, THE 
NAME COMES FROM AN OLD ENGLISH

427
00:24:08,415 --> 00:24:15,355
WORD, CLOSE TO EARTHA, I'M NOT 
SURE I'M PRONOUNCING IT RIGHT,

428
00:24:15,355 --> 00:24:20,994
BUT THE TERM GOES BACK AT LEAST 
OVER 1,000 YEARS, PROBABLY AT

429
00:24:20,994 --> 00:24:25,598
LEAST 1500 YEARS THAT WE CAN 
TRACE IT THROUGH THE LANGUAGES,

430
00:24:25,598 --> 00:24:30,804
INCLUDING OLD AND MIDDLE ENGLISH 
FROM SIMILAR SOUNDING WORDS.

431
00:24:30,804 --> 00:24:37,911
THERE WAS, I BELIEVE, A, A 
MYTHOLOGICAL GOD OF THE EARTH,

432
00:24:37,911 --> 00:24:41,915
WITH A SOMEWHAT SIMILAR NAME, 
BUT, EARLIER THAN THAT, I'M NOT

433
00:24:41,915 --> 00:24:42,549
REAL SURE.

434
00:24:42,549 --> 00:24:46,186
IT IS A GOOD QUESTION FOR A 
LINGUISTICS' EXPERT.

435
00:24:46,186 --> 00:24:50,123
>> AND THE EARTH IS, INDEED, THE 
ONLY PLANET IN THE SOLAR SYSTEM

436
00:24:50,123 --> 00:24:57,030
THAT HAS A NAME THAT DOES NOT 
COME FROM GREEK OR ROMAN

437
00:24:57,030 --> 00:24:57,530
MYTHOLOGY.

438
00:24:57,530 --> 00:25:01,835
>> MY QUESTION IS, HOW DOES THE 
MAGNETIC FIELD CHANGE FROM NORTH

439
00:25:01,835 --> 00:25:02,502
TO SOUTH?

440
00:25:02,502 --> 00:25:05,505
>> THIS QUESTION IS A 
FUNDAMENTALLY IMPORTANT QUESTION

441
00:25:05,505 --> 00:25:08,608
FOR WHICH THERE IS NO CONSENSUS 
ANSWER.

442
00:25:08,608 --> 00:25:12,879
WHAT WE DO KNOW IS THAT THE 
EARTH'S MAGNETIC FIELD REVERSES

443
00:25:12,879 --> 00:25:13,613
ITSELF.

444
00:25:13,613 --> 00:25:17,684
LAST REVERSED ITSELF 700,000 
YEARS AGO, AND WHEN THIS

445
00:25:17,684 --> 00:25:24,057
HAPPENS, COMPASS DIRECTIONS WILL 
SLIP FROM NORTH TO SOUTH, AND

446
00:25:24,057 --> 00:25:27,427
THE MAY GETTIZATION WILL CHANGE 
OF THE EARTH, SUCH THAT MOLTEN

447
00:25:27,427 --> 00:25:31,331
ROCKS WHICH FREEZE CAN RECORD 
THE HISTORY OF THE EARTH'S

448
00:25:31,331 --> 00:25:36,269
MAGNIFICENTIC -- MAGNITUDIC 
FIELD, AND THIS IS HOW WE KNOW

449
00:25:36,269 --> 00:25:39,739
ABOUT THE BLAST TAKE TECTONIC 
MOVEMENTS, AND WE CAN RECORD THE

450
00:25:39,739 --> 00:25:41,975
CHANGING EARTH'S MAGNETIC FIELD.

451
00:25:41,975 --> 00:25:44,911
>> VIRGINIA, BEFORE WE RUN OUT 
OF TIME LET ME ASK YOU, WHY DID

452
00:25:44,911 --> 00:25:47,347
YOU PICK A JOB THAT DEALS WITH 
GEOLOGY?

453
00:25:47,347 --> 00:25:49,349
>> I JUST LIKE ROCKS.

454
00:25:49,349 --> 00:25:51,718
I LIKE BEING OUTDOORS.

455
00:25:51,718 --> 00:25:54,654
AND I LIKE USING MY MIND IN 
SOLVING PROBLEMS.

456
00:25:54,654 --> 00:25:59,459
AND I FOUND THAT GEOLOGY WAS A 
PLACE WHERE I COULD BE OUTDOORS,

457
00:25:59,459 --> 00:26:04,864
AND I COULD OBSERVE THINGS, AND 
I WAS USING MY MIND AT THE SAME

458
00:26:04,864 --> 00:26:07,667
TIME THAT I WAS ENJOYING BEING 
OUTDOORS.

459
00:26:07,667 --> 00:26:09,235
SO, I JUST LIKED IT.

460
00:26:09,235 --> 00:26:12,505
AND I'M LUCKY THAT I FOUND A JOB 
WHERE I CAN, ACTUALLY, GET PAID

461
00:26:12,505 --> 00:26:15,041
FOR DOING GEOLOGY.

462
00:26:15,041 --> 00:26:17,310
>> JEFF, IF SOMEONE IS 
INTERESTED IN FINDING A JOB IN

463
00:26:17,310 --> 00:26:20,980
EARTH SCIENCE, WHAT SHOULD HE OR 
SHE STUDY IN SCHOOL?

464
00:26:20,980 --> 00:26:24,484
>> SCIENCE IS ONE OF THE CAREERS 
THAT IS JUST SO EXCITING FOR A

465
00:26:24,484 --> 00:26:27,420
NUMBER OF REASONS.

466
00:26:27,420 --> 00:26:31,524
YOU HAVE ENTIRE FREEDOM TO 
EXPLORE NEW AREAS OF RESEARCH

467
00:26:31,524 --> 00:26:34,227
THAT NO ONE ELSE KNOWS ABOUT.

468
00:26:34,227 --> 00:26:39,532
IN ORDER TO BECOME A SCIENTIST, 
THE BEST SKILLS TO LEARN IN

469
00:26:39,532 --> 00:26:43,903
SCHOOL ARE ALL SKILLS, INCLUDING 
MATH, INCLUDING SCIENCE, AND

470
00:26:43,903 --> 00:26:46,606
BELIEVE IT OR NOT, INCLUDING 
WRITING SKILLS.

471
00:26:46,606 --> 00:26:50,443
EVEN SCIENTISTS, WHO ARE THE 
MARTYRS IN TERMS OF THE MATH AND

472
00:26:50,443 --> 00:26:54,714
SCIENCE, NEED TO BE ABLE TO 
CONVEY THEIR IDEAS TO OTHER

473
00:26:54,714 --> 00:26:57,917
PEOPLE AND TELL THEIR STORY TO 
THE WORLD.

474
00:26:57,917 --> 00:27:00,754
>> THANK YOU, VIRGINIA AND JEFF 
FOR ANSWERING QUESTIONS.

475
00:27:00,754 --> 00:27:02,455
I APPRECIATE YOU TAKING THE TIME 
TODAY.

476
00:27:02,455 --> 00:27:05,025
>> THANK YOU, JOAN AND TO ALL 
THE STUDENTS WHO SUBMITTED GREAT

477
00:27:05,025 --> 00:27:06,126
QUESTIONS TODAY.

478
00:27:06,126 --> 00:27:06,960
>> GREAT QUESTIONS.

479
00:27:06,960 --> 00:27:08,395
KEEP STUDYING SCIENCE.

480
00:27:08,395 --> 00:27:09,129
>> YES.

481
00:27:09,129 --> 00:27:11,865
>> OUR THANKS, ALSO, TO THE 
FOLKS HERE AT BOISE STATE

482
00:27:11,865 --> 00:27:14,401
UNIVERSITY'S EARTH SCIENCE 
RESEARCH LAB FOR HOSTING US.

483
00:27:14,401 --> 00:27:17,237
YOU CAN LEARN LOTS MORE ABOUT 
THE EARTH AND LOTS OF OTHER

484
00:27:17,237 --> 00:27:20,206
SCIENCE TOPICS ON THE SCIENCE 
TREK WEBSITE.

485
00:27:20,206 --> 00:27:23,877
WE'LL ANSWER MORE QUESTIONS 
ABOUT THE EARTH ON SCIENCE TREK

486
00:27:23,877 --> 00:27:24,611
THE WEB SHOW.

487
00:27:24,611 --> 00:27:27,981
IF YOU WANT TO SUBMIT A QUESTION 
FOR SCIENCE TREK, IT'S EASY.

488
00:27:27,981 --> 00:27:30,150
YOU AND YOUR CLASS CAN WIN 
PRIZES.

489
00:27:30,150 --> 00:27:34,254
YOU CAN SEND US AN EMAIL OR A 
VIDEO QUESTION AND RECORD IT ON

490
00:27:34,254 --> 00:27:37,424
YOUR WEB CAM OR CELL PHONE, AND 
IF YOU ARE AN EDUCATOR, WE'LL

491
00:27:37,424 --> 00:27:38,525
LEND YOU A CAMERA.

492
00:27:38,525 --> 00:27:42,529
THE LAST PRIZE WINNER WAS DILLON 
IN MRS. JACOB'S CLASS AT KAMIAH

493
00:27:42,529 --> 00:27:43,229
ELEMENTARY.

494
00:27:43,229 --> 00:27:46,166
SO TO FIND OUT ABOUT THE EARTH 
AND HOW TO SEND IN QUESTIONS AND

495
00:27:46,166 --> 00:27:48,435
WIN, GO TO THE SCIENCE TREK 
WEBSITE.

496
00:27:48,435 --> 00:27:51,905
EACH WEEK, CHECK OUT MY BLOG FOR 
THE LATEST SCIENCE NEWS FOR

497
00:27:51,905 --> 00:27:52,272
KIDS.

498
00:27:52,272 --> 00:27:56,443
YOU WILL FIND IT ALL AT 
IDAHOPV.ORG/SCIENCETREK.

499
00:27:56,443 --> 00:27:57,744
THANKS FOR JOINING US.

500
00:27:57,744 --> 00:28:02,182
WE'LL SEE YOU NEXT TIME ON 
SCIENCE TREK.

501
00:28:22,602 --> 00:28:24,137
>>> PRESENTATION OF SOIRG ON 
IDAHO PUBLIC TELEVISION IS MADE

502
00:28:24,137 --> 00:28:27,240
POSSIBLE THROUGH THE GENEROUS 
SUPPORT OF THE LAURA MOORE

503
00:28:27,240 --> 00:28:29,042
CUNNINGHAM FOUNDATION.

504
00:28:29,042 --> 00:28:32,078
COMMITTED TO FULFILLING THE 
MOORE FAMILY LEGACY OF BUILDING

505
00:28:32,078 --> 00:28:37,851
THE GREAT STATE OF IDAHO.

506
00:28:37,851 --> 00:28:40,720
>>> IF YOU WANT TO LEARN MORE 
ABOUT THIS TOPIC OR WATCH OUR

507
00:28:40,720 --> 00:28:44,357
VIDEOS, CHECK OUT THE SCIENCE 
TREK WEBSITE AT