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Narrator:
The history of our solar system
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Is the history of us,
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But how well do we really
understand our cosmic roots?
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To understand where we are now,
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We need to understand where
we were at the beginning.
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Narrator:
Remarkable new evidence
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Threatens to rewrite almost
everything we thought we knew
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About the birth of our
planetary backyard.
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Oluseyi:
The history of the solar system
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Isn't as neat as
eight planets formed
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And now they're the same
eight planets today.
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Greene: Anything that challenges
the status quo
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And our thinking about
that is profound.
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It profoundly changes our
sense of how we got to be.
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Narrator:
Did one of the largest stars
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That ever lived
give birth to the sun?
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Was our solar system home
to two stars, not just one?
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And did supersized
planets once roam
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Where the earth sits today?
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There were planets that
probably got ejected
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From the solar system entirely.
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There may have been planets
that were actually
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Thrown into the sun.
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Narrator: This is the all-new
birth story of our solar system,
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And the race to rewrite history.
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-- Captions by vitac --
www.Vitac.Com
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Captions paid for by
discovery communications
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♪
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Today, across the world,
scientists are grappling
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To solve a serious problem.
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Their best theories for
how our solar system formed
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Just don't add up.
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Understanding the history
of our solar system
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Really is the story
of our origin.
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We happen to be here
today on this planet,
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Because this planet formed
from the raw ingredients
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That formed our solar system.
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Narrator: For decades,
scientists have known
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That the sun and the planets
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Were born out of the same
cloud of gas and dust
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That collapsed under gravity
4.5 billion years ago.
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But that collapse needed
an extra ingredient
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To get things started.
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Somehow the cloud
has to collapse.
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Something has to
give it a shove,
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Make one area
denser than another,
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And then gravity
can take its course
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And bring things together,
and begin to form
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Our sun and the planets.
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But it doesn't just
happen spontaneously.
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There needs to be a trigger.
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Narrator: According to
the conventional theory,
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That trigger was a supernova --
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An exploding star.
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The supernova sends a
shock wave of material
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Blasting through space.
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It smashes into a nearby
cloud of gas and dust,
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Forcing it to collapse.
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A new star, our sun,
sparks into life.
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And the remaining
swirls of gas and dust
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Condense into planets.
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Our solar system is born.
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♪
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The supernova trigger theory
has reigned supreme for decades,
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But remarkable new evidence
now threatens to override it.
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At the university of california,
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Ed young hunts for
cast-iron evidence
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To support the supernova
trigger theory.
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He studies some of
the rarest rocks on earth.
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Meteorites that are
as old as the sun.
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Young: I'm pulling out this
particular meteorite.
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It's a meteorite that
fell in australia in 1960.
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It's about 4.5 billion
years old, very ancient.
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This rock is pretty much as old
as the age of the solar system.
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Narrator: Ed looks for chemicals
inside these early rocks.
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These chemicals could
prove a supernova shock wave
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Really did trigger the formation
of our solar system.
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Young: The solar system formed
by the triggering event
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Being a supernova, then
this rock would contain
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Some of the material
that was spewed out
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By the supernova
at the time of the explosion.
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Oluseyi:
When a supernova explodes,
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It sends out radiation
in every direction,
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And that radiation
encounters other stuff,
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And the fingerprint
of the supernova
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Is left on everything
it touches.
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Narrator: Ed looks for traces
of a chemical
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That forms in the abundance
in supernova shock waves.
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It's called iron-60.
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Young: We use this
instrument to measure
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With great precision
the various elements
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That make up that meteorite.
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If we find evidence for iron-60,
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Then we have possible evidence
for a supernova nearby
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At the time
the solar system formed,
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Because supernovae
form the iron-60.
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Narrator:
The team prepares the sample.
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They grind the meteorite,
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Setting its
primordial grains free
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After 4.5 billion
years of imprisonment.
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Then, they dissolve
the grains in acid
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And finally, place the sample
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Inside a machine to measure
its chemical composition.
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The machine heats the sample
to extreme temperatures,
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Smashing it into its
component chemicals.
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Young: We walked our sample over
to this mass spectrometer.
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It has a plasma that's as hot
as the surface of the sun,
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And so it's a very efficient way
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Of analyzing ratios of elements
that we put in there.
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Narrator:
After just a few minutes,
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The results flash up
on ed's screen.
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They list the type and abundance
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Of every chemical
in the meteorite.
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But how much of the supernova
marker, iron-60, will he find?
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Young:
The slope of this line indicates
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A modest amount of iron-60
in the early solar system.
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Less than had previously
been estimated.
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Narrator: The result
is a surprising setback
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For the supernova
trigger theory.
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Young: The fact that this
slope is lower
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And the amount of iron-60
that implies
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Is less than previously thought,
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Tends to argue
against the notion
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That there was
a supernova exploding
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Right near where
the solar system was born
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At the time it was forming.
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Narrator: Ed's results suggest
that a supernova
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Can't have triggered the
formation of our solar system.
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If the violent
winds of a supernova
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Didn't provide the trigger...
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What did?
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Young: Now that we know that
iron-60 is not a smoking gun,
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We have to start rethinking
the origins of other isotopes
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That were present in
the early solar system.
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Narrator:
Ed goes back to his results.
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He searches for unusual levels
of other chemical elements.
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One stands out --
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Aluminum-26.
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Young: Unlike iron-60,
aluminum-26 can be formed
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By other ways --
ways other than a supernova.
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Narrator:
Aluminum-26 is commonly produced
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By oversized stars.
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But there's only one monster
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With the power to kickstart
the birth of a solar system.
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A giant wolf-rayet star,
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50 times the size of the sun.
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The most massive, brightest
breed of star in the universe.
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Hidden under the surface,
it's a cosmic chemical factory,
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Fusing atoms
of hydrogen together
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To produce heavier elements
like oxygen and aluminum
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But, crucially, not iron-60.
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This stellar furnace
creates so much heat
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It unleashes winds of nearly
five million miles per hour,
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Which slam into the surrounding
clouds of cosmic gas and dust,
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Sweeping them away from the star
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And piling them up into a dense,
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Chemically-rich shell
of material,
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Trillions of miles wide.
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If a supernova didn't explode
and collapse the cloud
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That made the sun,
what could have?
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Well, maybe it was a very, very
high-mass, luminous star.
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There's a type of star like that
called a wolf-rayet star,
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And they are incredibly
violent, blasting out radiation.
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Narrator: Wolf-rayet stars
are extremely rare.
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Of the two billion
stars in the milky way,
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Astronomers have
only spotted 600
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Of these spectacular,
bloated objects.
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Thaller: They are very,
very massive stars
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That are almost ripping
themselves apart with winds.
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Winds of high
energy charged particles.
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Oluseyi: The winds
of a wolf-rayet star
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Are almost like a slow
explosion of the star,
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And because that's the case,
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You don't get these
radioactive iron elements,
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So the fingerprint of
the wolf-rayet is very different
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Than that of the supernova.
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Narrator: Did the ferocious
winds from a wolf-rayet star
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Trigger the creation
of our solar system?
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The theory ticks
a number of boxes,
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With one exception.
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The clouds of gas
that give birth to stars
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Are normally very cold,
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But wolf-rayet stars and the
winds they throw out into space
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Are scorching hot.
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Far too hot to form
a star like the sun.
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But could
the chemical-rich shell
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That surrounds these
massive stars hold a clue?
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♪
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♪
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Narrator:
At the university of chicago,
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Astrophysicist vikram dwakadas,
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Part of a team
that uses computer simulations
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To peer inside giant
wolf-rayet stars.
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He wants to know if the outer
shell of one of these stars
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Might have triggered the
creation of our solar system.
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Dwarkadas:
The solar system cannot be
formed too close to the star
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Because these stars
are very hot.
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The wolf-rayet star
is very small out here.
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It's a single point
at the center,
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And in fact, this single point
is still about a few times,
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Up to 15 times
the size of our sun.
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Then this medium out here
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Could go up to about 10 billion
times the size of our sun.
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Narrator:
Vikram believes the distant
outer shells of wolf-rayet stars
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00:10:50,884 --> 00:10:56,354
Have all the raw chemicals
needed to build a solar system.
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And because this dense layer
lies trillions of miles away
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From the hot central star,
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00:11:01,862 --> 00:11:05,196
It may have just the right
temperature for star birth.
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00:11:07,134 --> 00:11:08,800
Dwarkadas: What this animation
shows, basically,
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00:11:08,802 --> 00:11:11,336
Is the environment around
the wolf-rayet star,
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And what you're seeing is
basically the density structure.
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00:11:14,274 --> 00:11:16,441
So, you can see that there's
very low density inside
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And very high density outside,
which we call the dense shell.
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Narrator: Vikram is convinced
that our solar system
215
00:11:23,016 --> 00:11:28,687
Was born inside the dense outer
shell of a wolf-rayet star.
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00:11:28,689 --> 00:11:31,222
But to prove his theory,
he needs to show
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00:11:31,224 --> 00:11:35,760
These cooler, outer layers
can be rich in aluminum-26 --
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00:11:35,762 --> 00:11:39,164
The chemical found in
abundance in early meteorites.
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00:11:40,467 --> 00:11:42,767
Dwarkadas: The aluminum-26
is produced by the star
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00:11:42,769 --> 00:11:45,470
At the very center,
and what we want to know first
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00:11:45,472 --> 00:11:47,505
Is whether it can
survive its journey
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00:11:47,507 --> 00:11:51,242
All the way from here
out to the dense shell.
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00:11:51,244 --> 00:11:54,913
Narrator: Vikram suspects
the delicate aluminum-26 atoms
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00:11:54,915 --> 00:11:58,083
Survive by attaching
themselves to particles
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Blown away from the giant star.
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00:12:01,588 --> 00:12:03,521
We find that dust
forms around the star
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During the wolf-rayet phase,
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00:12:04,991 --> 00:12:07,192
And in our theory, the iron
actually hitches a ride
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On the backs of
these dust rings.
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Narrator:
Vikram's ideas are very new,
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00:12:14,134 --> 00:12:17,068
But if he's right,
we can piece together
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00:12:17,070 --> 00:12:19,604
A new birth story
for our solar system...
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00:12:21,575 --> 00:12:24,609
...Around one of the largest
stars that ever lived.
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00:12:25,746 --> 00:12:28,413
The wolf-rayet shell
is enormous --
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00:12:28,415 --> 00:12:32,884
20,000 times the size
of our solar system.
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00:12:32,886 --> 00:12:34,619
Peeling back the outer layers
237
00:12:34,621 --> 00:12:38,923
Reveals a concentrated
patch of gas and dust.
238
00:12:38,925 --> 00:12:43,128
A gust of hot stellar wind
slams into the patch,
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00:12:43,130 --> 00:12:46,064
Triggering it to collapse.
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00:12:46,066 --> 00:12:49,200
It starts to spin,
and flattens out into a disc.
241
00:12:50,904 --> 00:12:54,005
The pressure at the
center rises so much
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00:12:54,007 --> 00:12:56,074
It triggers a new dawn.
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00:12:57,210 --> 00:13:00,545
The gas ignites,
and gives birth to the sun.
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00:13:01,715 --> 00:13:04,549
That's how the hot
winds of a giant star
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00:13:04,551 --> 00:13:08,820
Can breathe life into thousands
of others, like our sun.
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00:13:11,491 --> 00:13:14,559
These findings change everything
we thought we knew
247
00:13:14,561 --> 00:13:16,461
About our cosmic birth story.
248
00:13:18,231 --> 00:13:21,633
It's kind of neat to think
that it might be one of these
249
00:13:21,635 --> 00:13:24,803
Rare, beautiful, violent stars
250
00:13:24,805 --> 00:13:28,673
That triggered
the formation of us.
251
00:13:28,675 --> 00:13:31,142
Thaller: That means that we come
from something rather special.
252
00:13:31,144 --> 00:13:33,511
In many ways,
creation and destruction
253
00:13:33,513 --> 00:13:35,446
Turn out to be
two sides of the same coin.
254
00:13:36,817 --> 00:13:39,551
Narrator: New investigations
and new evidence
255
00:13:39,553 --> 00:13:41,853
Are forcing astronomers
to reconsider
256
00:13:41,855 --> 00:13:44,155
The birth story
of our solar system.
257
00:13:45,559 --> 00:13:47,559
But is that all
we've gotten wrong?
258
00:13:49,162 --> 00:13:52,330
Is it possible that our
sun was born with a twin?
259
00:13:54,634 --> 00:13:57,836
Astronomers find planets
in other solar systems
260
00:13:57,838 --> 00:14:00,071
Revolving around two stars,
261
00:14:00,073 --> 00:14:02,006
Or sometimes more.
262
00:14:02,008 --> 00:14:05,510
Thaller:
It is so easy to assume that
we are the normal things.
263
00:14:05,512 --> 00:14:08,446
That we are not the exception
to the rest of the rules.
264
00:14:08,448 --> 00:14:09,848
When you look up
into the night sky,
265
00:14:09,850 --> 00:14:11,950
You see all these
stars overhead,
266
00:14:11,952 --> 00:14:15,386
But do you realize that most
of those are not a single star?
267
00:14:15,388 --> 00:14:17,889
They're actually two stars
that are so close together
268
00:14:17,891 --> 00:14:19,924
You can't actually
see them as separate?
269
00:14:22,996 --> 00:14:25,430
Narrator: Of all the stars
in the night sky,
270
00:14:25,432 --> 00:14:29,667
Around 80% sit so close
to a neighboring star
271
00:14:29,669 --> 00:14:31,469
That they orbit
around each other.
272
00:14:32,505 --> 00:14:34,672
These gravitationally
bound stars
273
00:14:34,674 --> 00:14:37,008
Are known as binary pairs.
274
00:14:38,144 --> 00:14:41,079
Oluseyi: A binary star system
is when two stars
275
00:14:41,081 --> 00:14:43,882
Are locked in orbit
around each other,
276
00:14:43,884 --> 00:14:46,517
And that's a very common
scenario,
277
00:14:46,519 --> 00:14:49,053
But binaries
are incredibly common
278
00:14:49,055 --> 00:14:51,356
And they're very important
for understanding
279
00:14:51,358 --> 00:14:53,324
How stars form and evolve.
280
00:14:55,462 --> 00:14:57,762
Narrator: But if binary pairs
are so common,
281
00:14:57,764 --> 00:15:01,566
How come we don't see two suns
in the sky instead of one?
282
00:15:03,670 --> 00:15:07,005
Astronomers always assumed
the sun was born alone.
283
00:15:09,743 --> 00:15:12,243
But startling new
evidence suggests
284
00:15:12,245 --> 00:15:14,045
We may have gotten
that wrong, too.
285
00:15:17,083 --> 00:15:19,450
Harvard astronomer sarah sadavoy
286
00:15:19,452 --> 00:15:21,386
Studies star nurseries.
287
00:15:22,355 --> 00:15:24,656
These are the vast clouds of gas
288
00:15:24,658 --> 00:15:28,793
Where star birth
is still going on today.
289
00:15:28,795 --> 00:15:31,562
Sadavoy:
Ultimately what we want to
understand is how stars form.
290
00:15:31,564 --> 00:15:34,933
How do planets form?
How do solar systems form?
291
00:15:34,935 --> 00:15:38,102
And it's a long process,
and so we need to look at
292
00:15:38,104 --> 00:15:39,804
A number of different
observations
293
00:15:39,806 --> 00:15:41,205
In order to really pick out
294
00:15:41,207 --> 00:15:43,041
What's going on
at different stages.
295
00:15:44,945 --> 00:15:49,814
Narrator: Her primary target is
this -- the perseus cloud,
296
00:15:49,816 --> 00:15:52,650
An enormous haze
of gas and dust,
297
00:15:52,652 --> 00:15:56,087
And a fertile birthing
ground for sun-like stars.
298
00:15:57,490 --> 00:16:00,358
The perseus molecular cloud
is like the perfect laboratory
299
00:16:00,360 --> 00:16:01,726
To look at star formation.
300
00:16:01,728 --> 00:16:03,328
It's nearby.
301
00:16:03,330 --> 00:16:05,430
It's only 750 light-years away,
302
00:16:05,432 --> 00:16:07,131
So very, very close to us.
303
00:16:07,133 --> 00:16:08,700
It's a really active cloud,
304
00:16:08,702 --> 00:16:10,835
So it's got lots and lots
of star formation
305
00:16:10,837 --> 00:16:13,771
Ongoing within it, and it's
also a star forming region
306
00:16:13,773 --> 00:16:17,075
That's forming stars very
much like our own sun.
307
00:16:17,077 --> 00:16:20,378
Narrator:
Deep within the perseus cloud,
308
00:16:20,380 --> 00:16:25,650
Star birth takes place inside
the densest patches of gas.
309
00:16:25,652 --> 00:16:27,785
Sarah calls them "cocoons".
310
00:16:30,423 --> 00:16:33,224
She uses one of the world's
most powerful telescopes
311
00:16:33,226 --> 00:16:36,094
To map out these cocoons.
312
00:16:36,096 --> 00:16:39,163
The james clerk maxwell
telescope on hawaii.
313
00:16:40,533 --> 00:16:43,468
Sadavoy: This is a dust map
showing where dust is located.
314
00:16:43,470 --> 00:16:45,236
It's a three color
image indicating
315
00:16:45,238 --> 00:16:47,038
The different
temperatures of the dust,
316
00:16:47,040 --> 00:16:48,740
So, red corresponds
to colder dust
317
00:16:48,742 --> 00:16:51,376
And blue corresponds
to warmer dust.
318
00:16:51,378 --> 00:16:55,013
So, you can see, here are all
of the little cocoons
319
00:16:55,015 --> 00:16:57,882
Where young stars
are going to form out of.
320
00:16:57,884 --> 00:17:00,018
Just for size reference,
our solar system
321
00:17:00,020 --> 00:17:03,121
Would fit inside each
of these little cocoons.
322
00:17:05,091 --> 00:17:06,991
Narrator:
Once she's mapped them out,
323
00:17:06,993 --> 00:17:11,662
Sarah turns to the mighty vla
radio telescope in new mexico.
324
00:17:11,664 --> 00:17:14,932
She uses it to gaze
deeply into each cocoon
325
00:17:14,934 --> 00:17:20,638
And reveal if it's hatching a
single star, or a binary pair.
326
00:17:20,640 --> 00:17:23,474
Sadavoy: What I did was I took
radio observations,
327
00:17:23,476 --> 00:17:25,643
Looking at all of
the young stars
328
00:17:25,645 --> 00:17:27,445
In the perseus molecular cloud,
329
00:17:27,447 --> 00:17:30,415
And I combined that
with observations
330
00:17:30,417 --> 00:17:32,016
Of all of the dense cores,
331
00:17:32,018 --> 00:17:35,019
The cocoons that these young
stars formed out of.
332
00:17:35,021 --> 00:17:37,688
So, you've got the black
corresponding to the core.
333
00:17:37,690 --> 00:17:39,557
That's where the dust
is located,
334
00:17:39,559 --> 00:17:41,426
And then you've got
these white stars
335
00:17:41,428 --> 00:17:43,094
That are labeled that indicate
336
00:17:43,096 --> 00:17:45,563
Where the young stars are found.
337
00:17:45,565 --> 00:17:48,466
Narrator:
What sarah finds is astonishing,
338
00:17:48,468 --> 00:17:50,168
And it raises new questions
339
00:17:50,170 --> 00:17:52,870
About the birth of our sun.
340
00:17:52,872 --> 00:17:58,543
♪
341
00:18:05,018 --> 00:18:10,354
♪
342
00:18:10,356 --> 00:18:13,024
Narrator: With the help
of a powerful radio telescope,
343
00:18:13,026 --> 00:18:15,393
Harvard astronomer sarah sadavoy
344
00:18:15,395 --> 00:18:17,562
Peers deep into
the perseus cloud
345
00:18:17,564 --> 00:18:21,332
To find out more about how
sun-like stars are born.
346
00:18:22,936 --> 00:18:26,404
What she sees is remarkable.
347
00:18:26,406 --> 00:18:28,506
Diving into the perseus cloud
348
00:18:28,508 --> 00:18:30,842
Reveals a stellar
birthing ground.
349
00:18:33,913 --> 00:18:38,182
Deep within is a strange
bean-shaped cocoon of gas.
350
00:18:39,752 --> 00:18:43,421
Inside, a newborn star.
351
00:18:43,423 --> 00:18:46,324
But it's not alone
in its cradle.
352
00:18:46,326 --> 00:18:50,728
A mysterious second body
dances alongside it,
353
00:18:50,730 --> 00:18:53,698
A partner star.
354
00:18:53,700 --> 00:18:56,601
Spinning inside their
shared birthing cocoon,
355
00:18:56,603 --> 00:18:59,504
These stellar twins
are not unique.
356
00:19:01,241 --> 00:19:04,008
Lifting the lids
on all the cocoons
357
00:19:04,010 --> 00:19:08,980
Reveals that out here, no
sun-like star is born alone.
358
00:19:12,452 --> 00:19:15,920
The upshot of sarah's
study is jaw-dropping.
359
00:19:15,922 --> 00:19:19,323
If every sun-like star
is born with a twin,
360
00:19:19,325 --> 00:19:23,161
Perhaps our star was
born with a twin, too.
361
00:19:23,163 --> 00:19:26,898
Sadavoy:
What we find with these models
is that all stars like our sun
362
00:19:26,900 --> 00:19:29,433
Likely formed in binary pairs
363
00:19:29,435 --> 00:19:32,737
So that they had a companion
when they initially formed.
364
00:19:32,739 --> 00:19:34,639
And in the case of
our solar system,
365
00:19:34,641 --> 00:19:38,242
Something happened and our sun
no longer has its companion.
366
00:19:38,244 --> 00:19:43,080
This study showed that every
sun-like star was forming,
367
00:19:43,082 --> 00:19:46,551
Every single one,
was in a binary system,
368
00:19:46,553 --> 00:19:51,122
But yet, here our sun is
without a binary partner.
369
00:19:51,124 --> 00:19:53,991
Narrator: The idea of two stars
in our solar system
370
00:19:53,993 --> 00:19:57,161
Sounds like a science
fiction dream,
371
00:19:57,163 --> 00:19:59,664
But would the earth
and life itself
372
00:19:59,666 --> 00:20:03,034
Have evolved to see the wonder
of a double sunrise?
373
00:20:04,204 --> 00:20:07,305
Unfortunately,
the chances seem slim.
374
00:20:07,307 --> 00:20:10,274
If the sun was actually
part of a binary system,
375
00:20:10,276 --> 00:20:12,910
Things would be
radically different,
376
00:20:12,912 --> 00:20:15,079
And it raises the question --
377
00:20:15,081 --> 00:20:16,614
Would there be life
on this planet?
378
00:20:16,616 --> 00:20:18,416
Would this planet be here?
379
00:20:20,286 --> 00:20:23,454
Narrator: Although planets
can exist around binary stars,
380
00:20:23,456 --> 00:20:25,823
The earth may have been
a very different place
381
00:20:25,825 --> 00:20:27,792
If the sun had kept its twin.
382
00:20:31,864 --> 00:20:33,898
The combined heat from two stars
383
00:20:33,900 --> 00:20:36,968
Would've roasted
the young earth,
384
00:20:36,970 --> 00:20:39,036
Perhaps boiling away the oceans
385
00:20:39,038 --> 00:20:41,672
And creating a crushing
acidic atmosphere.
386
00:20:43,276 --> 00:20:46,310
Surface temperatures
would've soared.
387
00:20:46,312 --> 00:20:48,779
Life as we know it
would've been impossible
388
00:20:48,781 --> 00:20:50,848
In this hot, toxic hellhole.
389
00:20:54,420 --> 00:20:56,587
In a sky full of double stars,
390
00:20:56,589 --> 00:21:00,524
It seems like our small blue
planet may have gotten lucky.
391
00:21:02,095 --> 00:21:05,997
And if that's true, how
did we lose our companion?
392
00:21:05,999 --> 00:21:10,234
Narrator: Could the chaos of the
sun's early years be to blame?
393
00:21:10,236 --> 00:21:12,737
One possible scenario
could've played out
394
00:21:12,739 --> 00:21:15,339
Inside the sun's
stellar nursery.
395
00:21:17,277 --> 00:21:20,311
Over 4.5 billion years ago,
396
00:21:20,313 --> 00:21:22,580
Inside a stellar nursery,
397
00:21:22,582 --> 00:21:24,782
Hundreds of gigantic
birthing cocoons
398
00:21:24,784 --> 00:21:27,051
Are busy incubating stars.
399
00:21:29,322 --> 00:21:33,090
Inside one of them is our
newly-formed infant sun.
400
00:21:37,263 --> 00:21:40,064
As it swirls its way
through the stellar dust,
401
00:21:40,066 --> 00:21:45,736
A second star comes into view --
the sun's twin.
402
00:21:45,738 --> 00:21:48,939
An immense, second
cocoon passes by,
403
00:21:50,243 --> 00:21:53,411
And its massive gravity
rips our sun's twin
404
00:21:53,413 --> 00:21:55,846
From its cosmic cradle
405
00:21:55,848 --> 00:21:59,250
And throws it out into
the wilderness of the cosmos.
406
00:22:02,522 --> 00:22:04,989
Sadavoy: The more likely
situation for the sun
407
00:22:04,991 --> 00:22:06,724
Is two stars splitting apart,
408
00:22:06,726 --> 00:22:08,659
Getting flung off into
different directions
409
00:22:08,661 --> 00:22:11,262
Within our own galaxy.
410
00:22:11,264 --> 00:22:14,131
They're now millions
of millions of miles apart.
411
00:22:14,133 --> 00:22:17,168
There is no way to tell
which star in the night sky
412
00:22:17,170 --> 00:22:19,870
Is our companion star,
or was our companion star
413
00:22:19,872 --> 00:22:21,138
Back in the day
414
00:22:21,140 --> 00:22:24,342
And likely we are never
to meet it ever again.
415
00:22:24,344 --> 00:22:27,445
Our sister star
that formed right with us
416
00:22:27,447 --> 00:22:29,780
Could be clear on the other side
of the galaxy.
417
00:22:31,250 --> 00:22:33,451
Narrator: Piece by piece,
astronomers attempt
418
00:22:33,453 --> 00:22:38,589
To rewrite the birth story
of our home star -- the sun.
419
00:22:38,591 --> 00:22:40,157
But what about the planets?
420
00:22:40,159 --> 00:22:43,561
Do they hide
a secret history, too?
421
00:22:43,563 --> 00:22:44,962
The history of the solar system
422
00:22:44,964 --> 00:22:47,965
Isn't as neat as --
eight planets formed
423
00:22:47,967 --> 00:22:50,801
And now, they're the same
eight planets today.
424
00:22:50,803 --> 00:22:53,471
The early solar system
was very much different
425
00:22:53,473 --> 00:22:55,740
Than the solar system
we now live in.
426
00:22:55,742 --> 00:22:57,808
Narrator:
And could a rare mineral
427
00:22:57,810 --> 00:23:00,845
Reveal a new history
for how the earth
428
00:23:00,847 --> 00:23:04,081
Came to be the perfect
oasis for life?
429
00:23:04,083 --> 00:23:09,086
♪
430
00:23:15,328 --> 00:23:21,098
♪
431
00:23:21,100 --> 00:23:24,001
Narrator: Planet earth
is bathed in warmth,
432
00:23:24,003 --> 00:23:27,571
As it orbits close in to
our mother star, the sun.
433
00:23:29,942 --> 00:23:32,510
The size of our planet
is perfect for gravity
434
00:23:32,512 --> 00:23:34,412
To attract a thick atmosphere
435
00:23:36,082 --> 00:23:39,450
And allow oceans of liquid
water to pool on the surface.
436
00:23:41,421 --> 00:23:43,521
For us, it's paradise.
437
00:23:45,391 --> 00:23:48,426
But how many other worlds
just like it are out there?
438
00:23:50,830 --> 00:23:53,697
Scientists look
to distant stars,
439
00:23:53,699 --> 00:23:57,535
Hoping to find similar
warm, wet planets.
440
00:23:57,537 --> 00:23:59,470
What they find is shocking.
441
00:24:01,741 --> 00:24:05,376
In the region where the earth
sits in our solar system,
442
00:24:05,378 --> 00:24:08,979
Astronomers find a very
different type of planet.
443
00:24:08,981 --> 00:24:10,781
When we look around the galaxy,
444
00:24:10,783 --> 00:24:13,417
We see that the most common
type of terrestrial planet
445
00:24:13,419 --> 00:24:16,086
Is what we call a super-earth.
446
00:24:16,088 --> 00:24:18,622
The term super-earth
refers to a planet --
447
00:24:18,624 --> 00:24:20,691
A solid planet --
that is somewhere between
448
00:24:20,693 --> 00:24:23,160
Three and five times
the mass of the earth,
449
00:24:23,162 --> 00:24:26,797
And amazingly, these are the
most common types of planets
450
00:24:26,799 --> 00:24:29,166
In the universe.
451
00:24:29,168 --> 00:24:33,571
Narrator:
Super-earth planets are so
common around sun-like stars
452
00:24:33,573 --> 00:24:37,641
That astronomers now think our
ancient solar system
453
00:24:37,643 --> 00:24:41,011
May have had a family
of super-earths, too.
454
00:24:43,416 --> 00:24:45,749
This long-lost family of worlds
455
00:24:45,751 --> 00:24:48,452
Would've orbited
close in to the sun.
456
00:24:49,622 --> 00:24:51,856
So close that some
of their surfaces
457
00:24:51,858 --> 00:24:54,291
Could've seethed
with molten rock.
458
00:24:56,696 --> 00:24:58,896
Today, large super-earths
459
00:24:58,898 --> 00:25:02,066
Are nowhere to be seen
in our solar system.
460
00:25:02,068 --> 00:25:06,203
But if we did have them,
where did they go?
461
00:25:06,205 --> 00:25:08,739
And how did the earth
and other rocky planets
462
00:25:08,741 --> 00:25:10,407
Come to take their place?
463
00:25:12,512 --> 00:25:14,912
The answer could
lie in the chaos
464
00:25:14,914 --> 00:25:17,181
Of our fledgling solar system,
465
00:25:17,183 --> 00:25:19,183
When newborn planets
were jostling
466
00:25:19,185 --> 00:25:21,719
For their position
in the cosmos.
467
00:25:21,721 --> 00:25:23,120
Plait: These things were in
all different orbits,
468
00:25:23,122 --> 00:25:25,122
Elliptical orbits and they
would get close to each other,
469
00:25:25,124 --> 00:25:27,258
And so you were
constantly seeing
470
00:25:27,260 --> 00:25:29,493
Collisions between these things.
471
00:25:32,465 --> 00:25:34,498
It wasn't like cars
on a racetrack.
472
00:25:34,500 --> 00:25:36,667
It was more like a
demolition derby.
473
00:25:36,669 --> 00:25:38,869
There were planets
that probably got ejected
474
00:25:38,871 --> 00:25:41,672
From the solar system entirely.
There may have been planets
475
00:25:41,674 --> 00:25:44,208
That were actually
thrown into the sun.
476
00:25:44,210 --> 00:25:46,377
Narrator: But were these
mythical super-earths
477
00:25:46,379 --> 00:25:48,178
Really destroyed this way?
478
00:25:50,082 --> 00:25:52,516
A new theory suggests
that jupiter,
479
00:25:52,518 --> 00:25:55,152
The largest planet
in our solar system,
480
00:25:55,154 --> 00:25:56,554
May have been responsible
481
00:25:56,556 --> 00:25:59,757
For sending the
super-earths to their doom.
482
00:26:01,661 --> 00:26:06,263
Today, jupiter sits almost 500
million miles from the sun,
483
00:26:06,265 --> 00:26:08,832
But in the early days
of our solar system,
484
00:26:08,834 --> 00:26:12,903
Jupiter most likely migrated
in towards the super-earths.
485
00:26:14,373 --> 00:26:18,142
This trajectory
creates cosmic carnage.
486
00:26:18,144 --> 00:26:20,878
There's evidence of migration
of some of the giant planets
487
00:26:20,880 --> 00:26:23,447
In other solar systems,
and so we think
488
00:26:23,449 --> 00:26:25,149
That that same kind of process
489
00:26:25,151 --> 00:26:27,318
May have happened
in our own solar system.
490
00:26:28,921 --> 00:26:31,288
Narrator: This is the theory --
491
00:26:31,290 --> 00:26:34,058
4.5 billion years ago,
492
00:26:34,060 --> 00:26:38,395
Jupiter spirals inwards
through a young solar system.
493
00:26:38,397 --> 00:26:43,167
Its immense gravity smashes
the forming planets together,
494
00:26:43,169 --> 00:26:47,104
And snowplows their
corpses toward the sun,
495
00:26:47,106 --> 00:26:49,239
Piling up a gigantic
ridge of rubble.
496
00:26:49,241 --> 00:26:54,111
♪
497
00:26:54,113 --> 00:26:58,182
The pile of rubble meets
the family of super-earths.
498
00:26:58,184 --> 00:27:01,085
It disrupts their orbits.
499
00:27:01,087 --> 00:27:04,421
Eventually, they collide,
500
00:27:04,423 --> 00:27:09,093
Causing a planetary pileup that
annihilates the super-earths
501
00:27:09,095 --> 00:27:12,029
And leaves a cosmic
wasteland in their wake.
502
00:27:14,467 --> 00:27:16,500
Is jupiter really responsible
503
00:27:16,502 --> 00:27:18,502
For the death of
the super-earths?
504
00:27:18,504 --> 00:27:23,507
♪
505
00:27:23,509 --> 00:27:25,576
In switzerland,
506
00:27:25,578 --> 00:27:29,213
Scientist farhang nabiei
searches for evidence
507
00:27:29,215 --> 00:27:33,083
That long-lost planets
once roamed our solar system.
508
00:27:34,520 --> 00:27:38,522
Farhang studies a fragment of
the almahata sitta meteorite --
509
00:27:38,524 --> 00:27:40,591
An 88-ton space rock
510
00:27:40,593 --> 00:27:43,694
That exploded
over the nubian desert in sudan.
511
00:27:45,131 --> 00:27:47,931
This rare meteorite
is thought to have formed
512
00:27:47,933 --> 00:27:51,035
In the very early years
of the solar system,
513
00:27:51,037 --> 00:27:54,338
Perhaps even before
the earth itself was born.
514
00:27:56,275 --> 00:27:58,909
Tiny gemstones
inside the meteorite
515
00:27:58,911 --> 00:28:02,446
Offer a clue for where
the rocks were formed.
516
00:28:02,448 --> 00:28:05,516
These meteorites are from
the stony family of meteorites,
517
00:28:05,518 --> 00:28:07,284
So they are basically
full of rocks,
518
00:28:07,286 --> 00:28:10,721
And then one of the peculiar
characteristics of them
519
00:28:10,723 --> 00:28:12,156
Is that they have diamonds,
520
00:28:12,158 --> 00:28:14,758
And diamonds, to form,
they need high pressure,
521
00:28:14,760 --> 00:28:17,194
So they should be really
deep inside the planet.
522
00:28:18,731 --> 00:28:21,298
Narrator: It's impossible
for diamonds like these
523
00:28:21,300 --> 00:28:25,135
To form inside small asteroids.
524
00:28:25,137 --> 00:28:27,571
It takes a rock
the size of a planet
525
00:28:27,573 --> 00:28:29,807
To create the pressures
that are needed.
526
00:28:32,211 --> 00:28:35,245
This means the diamonds
in farhang's meteorite
527
00:28:35,247 --> 00:28:39,116
Were once part of a young
planet that got destroyed.
528
00:28:39,118 --> 00:28:41,318
Finding a diamond
inside of a meteorite
529
00:28:41,320 --> 00:28:45,089
Means that that meteorite was
once under high temperatures
530
00:28:45,091 --> 00:28:46,457
And high pressures,
531
00:28:46,459 --> 00:28:49,860
And that could only occur
inside of a planetary body.
532
00:28:49,862 --> 00:28:53,263
If this object is then broken up
by a catastrophic collision,
533
00:28:53,265 --> 00:28:55,032
Those diamonds can
be incorporated
534
00:28:55,034 --> 00:28:58,135
Into an asteroid,
a small asteroid.
535
00:28:59,305 --> 00:29:00,838
Narrator:
Are these diamonds a relic
536
00:29:00,840 --> 00:29:03,006
From a long-lost super-earth?
537
00:29:04,777 --> 00:29:08,078
Farhang looks inside
the diamonds themselves
538
00:29:08,080 --> 00:29:09,480
To see if there are clues
539
00:29:09,482 --> 00:29:12,483
To the size of the planet
they came from.
540
00:29:12,485 --> 00:29:15,252
Nabiei:
When diamonds are forming,
they trap minerals inside,
541
00:29:15,254 --> 00:29:17,654
And those things
are called inclusions.
542
00:29:17,656 --> 00:29:20,457
It's like when you
are freezing water,
543
00:29:20,459 --> 00:29:22,126
You put a small piece of stone.
544
00:29:22,128 --> 00:29:25,129
At the end, you have
that inside the ice.
545
00:29:25,131 --> 00:29:26,964
You want to cut out
those diamonds
546
00:29:26,966 --> 00:29:29,032
And look at those inclusions
and study
547
00:29:29,034 --> 00:29:31,769
And see what we can know
about this ancient planet.
548
00:29:34,640 --> 00:29:38,609
Narrator: Different minerals
form at different pressures.
549
00:29:38,611 --> 00:29:41,378
If farhang can identify
the raw materials
550
00:29:41,380 --> 00:29:43,347
Trapped inside these diamonds,
551
00:29:43,349 --> 00:29:47,184
He'll know the size of the
planet that they were formed in.
552
00:29:47,186 --> 00:29:51,221
The only trouble --
the mineral grains are tiny --
553
00:29:51,223 --> 00:29:54,658
As fine as a human hair.
554
00:29:54,660 --> 00:29:56,860
Luckily, farhang has access
555
00:29:56,862 --> 00:29:59,463
To a multimillion-dollar
microscope --
556
00:29:59,465 --> 00:30:02,800
One of the most advanced
of its kind in the world.
557
00:30:02,802 --> 00:30:06,503
So, this is the transmission
electron microscopes,
558
00:30:06,505 --> 00:30:09,773
Similar to, lets say,
biological microscope.
559
00:30:09,775 --> 00:30:14,144
Instead of light, it's electrons
going through the sample.
560
00:30:14,146 --> 00:30:17,047
And here's the sample that we
are gonna insert inside.
561
00:30:17,049 --> 00:30:24,521
♪
562
00:30:24,523 --> 00:30:27,591
Narrator: Moments later,
the results are in,
563
00:30:27,593 --> 00:30:30,327
And they reveal a surprise.
564
00:30:30,329 --> 00:30:34,264
The planet should be at least
about mercury- to mars-sized
565
00:30:34,266 --> 00:30:36,166
To have such a pressure
in its interior
566
00:30:36,168 --> 00:30:39,236
And form these inclusions
in diamonds.
567
00:30:39,238 --> 00:30:41,171
Narrator: The diamonds
are unlikely to have come
568
00:30:41,173 --> 00:30:44,274
From something the size
of a super-earth.
569
00:30:44,276 --> 00:30:46,210
But could their planet
of origin
570
00:30:46,212 --> 00:30:49,279
Have become part of the
rubble pile created by jupiter?
571
00:30:51,984 --> 00:30:54,651
Nabiei: These meteorites,
they have characteristics
572
00:30:54,653 --> 00:30:58,188
That shows that probably it has
formed somewhere quite close
573
00:30:58,190 --> 00:31:00,724
To jupiter, but in
the inner side of jupiter,
574
00:31:00,726 --> 00:31:03,727
Closer to the sun.
575
00:31:03,729 --> 00:31:05,996
Narrator:
Farhang's incredible analysis
576
00:31:05,998 --> 00:31:11,668
Proves that our solar system had
at least one long-lost planet.
577
00:31:11,670 --> 00:31:13,070
We'll have to wait for evidence
578
00:31:13,072 --> 00:31:16,340
Of the mysterious super-earths
to immerge.
579
00:31:16,342 --> 00:31:20,878
But if they did exist,
one question still remains --
580
00:31:20,880 --> 00:31:23,814
How did the earth
and other rocky planets
581
00:31:23,816 --> 00:31:25,949
Come to take their place?
582
00:31:25,951 --> 00:31:31,755
♪
583
00:31:38,163 --> 00:31:43,133
♪
584
00:31:43,135 --> 00:31:45,869
Narrator: As scientists continue
to rewrite the story
585
00:31:45,871 --> 00:31:47,838
Of the birth of our solar
system,
586
00:31:47,840 --> 00:31:51,508
They search for evidence
of long-lost super-earths.
587
00:31:51,510 --> 00:31:53,844
Did they exist, and, if so,
588
00:31:53,846 --> 00:31:57,414
How did the earth and other
rocky planets take their place?
589
00:31:57,416 --> 00:32:02,019
One theory holds
jupiter responsible.
590
00:32:02,021 --> 00:32:06,189
After 100,000 years of wreaking
havoc in the solar system,
591
00:32:06,191 --> 00:32:09,026
Jupiter finally moves away
from the sun,
592
00:32:09,028 --> 00:32:12,195
Leaving a trail of devastation.
593
00:32:12,197 --> 00:32:15,832
The super-earths are gone,
burned up in the sun,
594
00:32:15,834 --> 00:32:19,102
But the ridge of cosmic rubble
that jupiter piled up
595
00:32:19,104 --> 00:32:21,672
Can now start flattening out.
596
00:32:21,674 --> 00:32:26,243
Inside it, rocks collide and
merge to form new planets --
597
00:32:27,479 --> 00:32:32,582
Mercury...Venus...And earth.
598
00:32:32,584 --> 00:32:36,219
None of them are as big as
the super-earths they replace.
599
00:32:36,221 --> 00:32:39,856
But these lumps of hot rock
will go on to form the heart
600
00:32:39,858 --> 00:32:43,527
Of the solar system
that we know today.
601
00:32:43,529 --> 00:32:46,763
All thanks to jupiter
destroying the first generation
602
00:32:46,765 --> 00:32:48,966
Of super-earths.
603
00:32:48,968 --> 00:32:51,835
Right now, it's only a theory,
604
00:32:51,837 --> 00:32:54,972
But it may be that we don't
just have jupiter to thank
605
00:32:54,974 --> 00:32:58,141
For clearing the super
earths out of the way.
606
00:32:58,143 --> 00:33:00,110
The very rocks
under our feet
607
00:33:00,112 --> 00:33:03,413
Could be relics from the battle
that killed them.
608
00:33:03,415 --> 00:33:05,349
Through a process of collisions,
609
00:33:05,351 --> 00:33:07,651
Planets being thrown out
of the solar system,
610
00:33:07,653 --> 00:33:09,920
Planets being thrown
into the sun,
611
00:33:09,922 --> 00:33:12,856
We ended up with a situation
where what we call earth
612
00:33:12,858 --> 00:33:16,293
Is really perhaps the remnants
of early super-earths
613
00:33:16,295 --> 00:33:19,429
And other broken-apart
terrestrial protoplanets.
614
00:33:22,334 --> 00:33:24,668
Tremblay: If all of those
billions of years ago,
615
00:33:24,670 --> 00:33:28,038
Jupiter hadn't carried out
its colossal inward journey,
616
00:33:28,040 --> 00:33:30,741
Our solar system
could look completely different.
617
00:33:30,743 --> 00:33:33,110
In fact, it might look like
the other solar systems
618
00:33:33,112 --> 00:33:34,678
We see beyond own.
619
00:33:34,680 --> 00:33:37,881
For example, maybe our earth
would instead be a super-earth.
620
00:33:40,619 --> 00:33:43,687
Narrator: Scientists are writing
a brand-new birth story
621
00:33:43,689 --> 00:33:45,689
For our solar system.
622
00:33:45,691 --> 00:33:49,292
Born inside the shell
of a giant star,
623
00:33:49,294 --> 00:33:52,162
The infant sun was ripped
from its twin
624
00:33:52,164 --> 00:33:54,798
By a passing cocoon.
625
00:33:54,800 --> 00:33:58,135
And its first generation of
rocky children were destroyed,
626
00:33:59,738 --> 00:34:03,340
Allowing smaller planets like
the earth to take their place.
627
00:34:05,244 --> 00:34:08,045
Perhaps all these extraordinary
events had to occur
628
00:34:08,047 --> 00:34:10,414
For the earth to form,
629
00:34:10,416 --> 00:34:14,151
Just the right size and just
the right distance from the sun
630
00:34:14,153 --> 00:34:17,187
To support life like us.
631
00:34:17,189 --> 00:34:19,389
But for that life
to get going,
632
00:34:19,391 --> 00:34:23,727
One final extraordinary
event was required.
633
00:34:23,729 --> 00:34:26,029
The young earth needed water.
634
00:34:28,700 --> 00:34:31,468
But where did our planet
first get its water from?
635
00:34:33,372 --> 00:34:38,108
For decades, scientists believed
that our planet was born dry,
636
00:34:38,110 --> 00:34:40,544
Formed from dry materials.
637
00:34:40,546 --> 00:34:42,979
And our water arrived later,
638
00:34:42,981 --> 00:34:45,515
Most likely from asteroids
or comets
639
00:34:45,517 --> 00:34:47,284
Smashing into the surface.
640
00:34:47,286 --> 00:34:52,255
♪
641
00:34:52,257 --> 00:34:54,691
One of the oldest questions
we've had about earth is,
642
00:34:54,693 --> 00:34:57,127
Where did all of
this water come from?
643
00:34:57,129 --> 00:34:59,963
We thought that perhaps
it came to earth in asteroids
644
00:34:59,965 --> 00:35:03,834
Or comets, and for sure,
some probably did.
645
00:35:03,836 --> 00:35:07,971
Narrator:
Now, new evidence suggests
this dry earth hypothesis
646
00:35:07,973 --> 00:35:10,006
Could be completely wrong.
647
00:35:13,912 --> 00:35:16,446
Geophysicist steve jacobson
648
00:35:16,448 --> 00:35:20,383
Is convinced the rocks that came
together to form the early earth
649
00:35:20,385 --> 00:35:22,052
Were already wet...
650
00:35:26,125 --> 00:35:28,658
...And much
of this primordial water
651
00:35:28,660 --> 00:35:31,895
Remains still trapped
in the ground beneath our feet.
652
00:35:33,765 --> 00:35:36,333
Steve has spent his career
trying to prove
653
00:35:36,335 --> 00:35:38,168
His controversial theory.
654
00:35:38,170 --> 00:35:40,637
He studies a deep layer
of our planet
655
00:35:40,639 --> 00:35:42,439
Called the transition zone,
656
00:35:42,441 --> 00:35:46,743
Located about 370 miles below
the surface.
657
00:35:46,745 --> 00:35:48,979
Jacobson: I study
a part of the earth's interior
658
00:35:48,981 --> 00:35:51,348
That we can't visit.
659
00:35:51,350 --> 00:35:54,151
It's much too deep
in the planet,
660
00:35:54,153 --> 00:35:56,486
And so it's pretty difficult
being a geologist
661
00:35:56,488 --> 00:35:59,055
That can't do field work.
662
00:35:59,057 --> 00:36:02,125
Narrator: Steve believes
this deep layer of our planet
663
00:36:02,127 --> 00:36:05,695
Is full of a rare mineral
called ringwoodite,
664
00:36:05,697 --> 00:36:09,332
Which acted like a chemical
sponge when our planet formed,
665
00:36:09,334 --> 00:36:12,569
Soaking up
the earth's primordial water.
666
00:36:12,571 --> 00:36:15,038
In the transition zone,
it's possible that ringwoodite
667
00:36:15,040 --> 00:36:19,009
Could contain more water than
is found on the earth's surface.
668
00:36:19,011 --> 00:36:21,878
Narrator: Steve's about to put
his controversial theory
669
00:36:21,880 --> 00:36:23,346
To the test.
670
00:36:23,348 --> 00:36:30,153
♪
671
00:36:36,528 --> 00:36:41,364
♪
672
00:36:41,366 --> 00:36:44,467
Narrator: At the argonne
national laboratory in illinois,
673
00:36:44,469 --> 00:36:48,538
Geophysicist steve jacobson
is about to make a sample
674
00:36:48,540 --> 00:36:51,274
Of the rare mineral ringwoodite
675
00:36:51,276 --> 00:36:55,712
And find out
if it can absorb any water.
676
00:36:55,714 --> 00:36:58,782
He suspects ringwoodite
is made when a common earth rock
677
00:36:58,784 --> 00:37:02,452
Called olivine is subjected
to intense pressures,
678
00:37:02,454 --> 00:37:06,556
Like those found in the greater
depths of the earth's interior.
679
00:37:06,558 --> 00:37:09,125
Jacobson: The most interesting
thing about ringwoodite
680
00:37:09,127 --> 00:37:13,363
Is its ability to store
hydrogen and oxygen,
681
00:37:13,365 --> 00:37:15,632
The components of water.
682
00:37:15,634 --> 00:37:18,001
Narrator: Steve wants to know
how much water
683
00:37:18,003 --> 00:37:21,705
The earth's supply
of ringwoodite could be hiding.
684
00:37:21,707 --> 00:37:24,975
To find out, he takes
a powdered sample of olivine
685
00:37:24,977 --> 00:37:26,876
And adds water to it.
686
00:37:26,878 --> 00:37:33,049
The sample is now placed
at the center of this assembly,
687
00:37:33,051 --> 00:37:36,119
Made of tungsten carbide cubes,
which are gonna transfer
688
00:37:36,121 --> 00:37:40,156
The force from the press
to the sample.
689
00:37:40,158 --> 00:37:41,791
Narrator:
Steve subjects the mixture
690
00:37:41,793 --> 00:37:45,095
To the pressures found deep
in the transition zone.
691
00:37:45,097 --> 00:37:47,530
These are 300,000 times higher
692
00:37:47,532 --> 00:37:51,000
Than the pressure
found on the earth's surface.
693
00:37:51,002 --> 00:37:53,737
Jacobson: In the same way
that ice can be made from water
694
00:37:53,739 --> 00:37:55,639
When we change the temperature,
695
00:37:55,641 --> 00:37:58,808
When we change the pressure,
minerals can transform
696
00:37:58,810 --> 00:38:01,578
Into new minerals.
697
00:38:01,580 --> 00:38:06,216
Narrator:
The 1100-ton hydraulic press
transforms the olivine sample
698
00:38:06,218 --> 00:38:10,186
Into a microscopic grain
of ringwoodite.
699
00:38:10,188 --> 00:38:12,389
Jacobson: What's gonna come out
of the experiment
700
00:38:12,391 --> 00:38:14,190
Is no longer olivine.
701
00:38:14,192 --> 00:38:16,259
It's going to be ringwoodite.
702
00:38:16,261 --> 00:38:20,030
Now, that ringwoodite may or
may not have absorbed the water
703
00:38:20,032 --> 00:38:21,731
That we put into
the starting materials,
704
00:38:21,733 --> 00:38:25,068
And that's what
we're gonna find out next.
705
00:38:25,070 --> 00:38:28,104
Narrator: With his sample made,
steve just needs to determine
706
00:38:28,106 --> 00:38:30,607
How much water
the ringwoodite soaked up.
707
00:38:33,478 --> 00:38:36,613
He places the sample
in a spectroscope
708
00:38:36,615 --> 00:38:40,583
And fires a fine-tuned laser
beam to coax out the water
709
00:38:40,585 --> 00:38:44,154
Trapped inside the tiny,
blue-colored crystal.
710
00:38:44,156 --> 00:38:45,588
Jacobson:
When we change the pressure
711
00:38:45,590 --> 00:38:48,825
And we change the temperature,
using lasers,
712
00:38:48,827 --> 00:38:52,462
The water appears to come out
of the ringwoodite.
713
00:38:52,464 --> 00:38:55,598
Narrator: But how much water
does the ringwoodite contain?
714
00:38:55,600 --> 00:38:59,169
We found huge amounts
of water inside it.
715
00:38:59,171 --> 00:39:01,104
This peak represents --
716
00:39:01,106 --> 00:39:06,843
Probably 1 or 2%
of the crystals weight is water.
717
00:39:06,845 --> 00:39:09,846
Narrator:
2% may not sound like much,
718
00:39:09,848 --> 00:39:13,850
But there's a whole lot of
ringwoodite deep below our feet.
719
00:39:13,852 --> 00:39:16,619
Jacobson:
Now if ringwoodite throughout
the earth's mantle
720
00:39:16,621 --> 00:39:18,621
Contained this much water,
it would be equivalent
721
00:39:18,623 --> 00:39:22,292
To three or four times the
amount of water in the oceans.
722
00:39:22,294 --> 00:39:24,494
Narrator:
Amazingly, steve is convinced
723
00:39:24,496 --> 00:39:29,432
That this hidden water supply
is as old as our planet,
724
00:39:29,434 --> 00:39:32,569
Proving the earth
was born with water.
725
00:39:32,571 --> 00:39:34,170
This is too much water
726
00:39:34,172 --> 00:39:37,507
To have been added to the mantle
over geologic times,
727
00:39:37,509 --> 00:39:40,110
Suggesting that the earth
started off
728
00:39:40,112 --> 00:39:43,213
With quite a bit of water
from the beginning.
729
00:39:43,215 --> 00:39:45,548
Narrator:
Steve's theory allows scientists
730
00:39:45,550 --> 00:39:50,153
To write a brand-new birth story
for the earth's oceans,
731
00:39:50,155 --> 00:39:53,890
One where they are filled from
below, as well as from above.
732
00:39:53,892 --> 00:39:59,195
♪
733
00:39:59,197 --> 00:40:02,198
Nearly 4.4 billion years ago,
734
00:40:02,200 --> 00:40:05,568
When young earth
is parched and barren,
735
00:40:05,570 --> 00:40:09,572
Hidden roughly 370 miles
beneath its crust,
736
00:40:09,574 --> 00:40:12,242
A vast layer
of ringwoodite crystals
737
00:40:12,244 --> 00:40:14,210
With enough water trapped inside
738
00:40:14,212 --> 00:40:17,647
To fill our oceans
many times over.
739
00:40:17,649 --> 00:40:23,119
Heat rising from the area below
forces the crystals upwards,
740
00:40:23,121 --> 00:40:27,123
They melt and release water,
741
00:40:27,125 --> 00:40:31,027
Creating fast-rising plumes
of magma
742
00:40:31,029 --> 00:40:34,364
That explode onto the surface.
743
00:40:34,366 --> 00:40:39,068
Here the water condenses
and rains down onto earth,
744
00:40:39,070 --> 00:40:41,504
Filling up
the newly-formed oceans.
745
00:40:45,010 --> 00:40:47,143
Plait:
Most of the water on the earth
isn't even on the surface,
746
00:40:47,145 --> 00:40:48,645
It's locked up in the mantle.
747
00:40:48,647 --> 00:40:51,047
We didn't know that a few
years ago, and now we do.
748
00:40:51,049 --> 00:40:54,317
That changes our ideas
about where water came from.
749
00:40:54,319 --> 00:40:57,153
So there's always
the possibility
750
00:40:57,155 --> 00:40:59,556
That some new observation,
some new evidence
751
00:40:59,558 --> 00:41:03,226
Will come along and show,
"hey, we're wrong."
752
00:41:03,228 --> 00:41:06,262
Tremblay: If it turns out that
rocky planets like the earth
753
00:41:06,264 --> 00:41:08,431
Can form with water
already in them,
754
00:41:08,433 --> 00:41:10,767
That could suggest that there
are a lot more
755
00:41:10,769 --> 00:41:14,103
Water-rich planets out there
than we originally thought.
756
00:41:18,009 --> 00:41:21,744
Narrator: Chapter by chapter,
scientists are rewriting
757
00:41:21,746 --> 00:41:24,547
The birth story
of our solar system.
758
00:41:24,549 --> 00:41:28,485
But as technology develops
and new ideas come to light,
759
00:41:28,487 --> 00:41:31,821
How long will it be before
the next revision
760
00:41:31,823 --> 00:41:34,891
And the next after that?
761
00:41:34,893 --> 00:41:37,427
This is what's really exciting
about the process of science,
762
00:41:37,429 --> 00:41:40,063
Is that there's always
something new
763
00:41:40,065 --> 00:41:44,701
That can lead us in directions
that we never even imagined.
764
00:41:48,006 --> 00:41:50,507
The basic process
of scientific discovery
765
00:41:50,509 --> 00:41:54,644
Is looking at how things are,
finding small problems,
766
00:41:54,646 --> 00:41:57,480
Small chinks in the armor
of current theory,
767
00:41:57,482 --> 00:42:00,950
And using them as a wedge
to break that theory apart,
768
00:42:00,952 --> 00:42:04,020
Come up with new ideas
that radically enlarge
769
00:42:04,022 --> 00:42:06,155
The arena of reality
that we understand.
770
00:42:08,627 --> 00:42:11,094
Narrator: The birth story
of the solar system
771
00:42:11,096 --> 00:42:15,732
Is a story that we should revise
again and again.
772
00:42:15,734 --> 00:42:18,468
Because it is the story of us,
773
00:42:18,470 --> 00:42:20,837
And the better
we understand that,
774
00:42:20,839 --> 00:42:25,508
The better we understand
our place in the universe.