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Our universe
Is a place of infinite variety.
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Two trillion galaxies.
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Billions and billions of stars.
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And countless planets.
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Worlds beyond imagination.
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The universe is so vast,
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so incomprehensible, so terrifying,
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that I think it's quite natural
for us to choose
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to live out our lives
completely oblivious to it.
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Perhaps that's why there's a sense
of relief that rises with the dawn.
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The brightening sky hides the stars
and the questions that they pose.
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After all,
they are the biggest questions.
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How did the universe come to be?
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Why are we here?
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And how will it all end?
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We have to face those questions
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if we're ever to acquire
a truly deep understanding of ourselves.
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You see, astronomy challenges us.
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From one perspective,
we're just grains of sand adrift
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in an infinite and indifferent ocean.
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But from another perspective, we are
nature's most magnificent creation.
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Collections of atoms that can think
and wonder about the universe
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and choose to explore it.
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Five, four,
three, two, one.
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We have lift-off. All systems go.
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In our quest for answers,
we re venturing ever further from home,
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far beyond the planets...
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and out to the stars.
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Our spacecraft are sending back
a stream of extraordinary revelations.
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Visions of alien worlds...
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with the ingredients to create life.
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We've seen galaxies collide,
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black holes devouring star systems.
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And we may have glimpsed
the origin of the cosmos itself.
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With every new observation,
with every new piece of knowledge,
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there is the opportunity to acquire
a deeper understanding.
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And, as we answer
question after question
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we get ever closer to being able to tell
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what is surely
the greatest story ever told.
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NASA's Parker Solar Probe,
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a daring mission to shed light
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on the mysteries of our closest star.
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This is a journey
into never-never land you might say.
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NASA's Parker Solar Probe is
the first spacecraft to touch a star.
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It's designed to fly
through the Sun's atmosphere,
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braving temperatures
no spacecraft has ever endured.
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The Parker Solar Probe is
allowing us to know our star
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as we've never known it before.
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And it's also helping us
to tell the story of all the stars.
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Our Sun is from a long line of stars
dating back to the dawn of time.
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From fierce blue giants
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which first lit up the universe,
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to later generations,
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whose deaths enriched the cosmos
with precious elements,
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the building blocks of our solar system,
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and allowed our Sun to create the thing
which brings meaning to the cosmos.
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Life.
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You and me.
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We have
a strange relationship with the stars,
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somewhere between awe and indifference.
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I think we take our star,
the Sun, for granted,
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partly because of its predictability.
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Every day it rises in the east
and sets in the west,
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without any help or reverence from us.
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But many ancient cultures deified
the Sun.
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They treated it as a God,
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and the Sun gods were creators
and destroyers of worlds.
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So which is it?
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Well, I think that the modern story
of the stars as told by science,
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which is indisputably an epic story
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stretching back over 13 billion years
to the origin of the universe,
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places them firmly
in the realm of the gods.
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If we want to understand
where these gods came from...
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We have to go back...
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to a time before the stars.
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In the beginning the universe was dark.
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But it was not empty.
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Something was lurking in the void,
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stretching out tendrils.
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The cosmic web grew
to become a vast structure,
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criss-crossing the entire universe.
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It was formed by interlocking filaments
of dark matter,
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and it was at the places
where these filaments met
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the intersections,
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that the first stars,
our Sun's earliest ancestors, were born.
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00:12:01,080 --> 00:12:04,200
The cosmic web is
the scaffolding of the universe,
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the vast and intricate structure
that spans the void.
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The web is made
primarily out of dark matter,
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a mysterious substance
that dominates the universe,
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although we don't know what it is.
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It's one of the great mysteries
in modern physics.
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It's probably some kind of particle
that interacts very weakly with itself
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and with light.
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If it doesn't interact with light,
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we can't see it, which is
why it's called dark matter.
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But it does influence the universe
through its gravity.
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It was in the dark heart
of the cosmic web
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that gravity began to sculpt
the early universe,
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drawing together
the two simplest elements,
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hydrogen and helium.
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The raw material
for the very first stars.
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Hydrogen gas clings
to the filaments of the web,
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attracted there
by the gravitational pull
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of the dark matter.
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And where those filaments cross,
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the gas can become dense enough
to collapse under its own gravity
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to form great clusters of galaxies,
each filled with billions of stars.
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The universe was
approaching a turning point.
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Hydrogen and helium poured
into the regions
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where the filaments crossed,
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gathering into ever denser clouds.
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Gravity asserted its grip,
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and the clouds of gas began to collapse,
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becoming denser and denser.
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And in the densest regions,
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the gas became so hot...
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that nuclear fusion reactions began.
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And out of maelstrom,
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the first gods emerged,
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and there was light.
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The stars illuminate the universe,
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but that is the least interesting thing
that they do.
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The thing that makes
the universe interesting,
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that brings meaning to the universe is
that, life. You and me.
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And life is just chemistry.
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And chemistry requires
complex chemical elements.
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The only thing that existed
in the universe before the stars
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was hydrogen and helium.
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Life requires carbon
and oxygen and iron.
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All those things were made
in a process called nuclear fusion
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in the cores of stars,
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or even the heavier elements,
like gold, in the collisions of stars.
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So, without the stars,
the universe would be uninteresting.
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It would be meaningless.
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It would be just an infinite box of gas.
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The first stars were monsters.
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Hundreds of times as massive as our Sun.
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They burnt with such ferocity
that they shone blue,
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with surface temperatures
in excess of 100,000 degrees.
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They were the largest stars ever
to have lived.
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Violent and volatile giants.
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A star is essentially a balancing act.
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The force of gravity is
constantly trying to collapse it,
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and that pushes its ingredients,
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primarily hydrogen, single protons,
closer and closer together.
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Now, when those protons
get close enough together,
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another of the fundamental forces
of nature,
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the strong nuclear force, takes over,
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and it can stick the protons together.
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That releases energy which creates
a pressure which holds the star up.
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Now the more massive the star,
the stronger the inward pull of gravity
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and the more energy has to be released
to maintain the balance,
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and so the faster
the ingredients are used up.
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These giant stars were
in a struggle for survival,
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fighting the relentless pull of gravity,
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consuming more and more hydrogen fuel
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to maintain
their precarious equilibrium.
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For most of its life,
a star burns hydrogen,
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the simplest chemical element
with one proton in its nucleus,
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into helium with two protons.
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Now, when it runs out
of hydrogen in the core,
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the core starts to collapse and heat up,
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and the star responds by building
ever more complex elements.
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So it makes carbon with six protons
and oxygen with eight protons,
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releasing more
and more energy as it goes.
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But when the star has
assembled iron in its core,
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with 26 protons in its nucleus,
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no more energy can be released.
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The star loses
its battle against gravity.
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It collapses
and in a final moment of creation,
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salvaged if you like,
from its destruction,
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it distributes those newly minted
heavy chemical elements
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out into the universe.
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Imagine we could journey back in time
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and watch the first star live out
its brief luminous life.
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After only a million years
the star used up all of its fuel.
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The core collapsed.
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The star imploded.
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And then rebounded...
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in a colossal explosion.
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A supernova.
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In death, the first stars began
to transform the cosmos,
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enriching the ocean
of hydrogen and helium
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which filled the universe
with heavy elements...
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to build new generations
of more complex stars.
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Over time,
these elements gathered together,
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creating rich clouds of gas and dust.
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Nurseries where new generations
of stars were born.
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And not just stars,
but families of stars.
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The first galaxies.
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And around this time,
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some of the earliest star systems
formed in our own galaxy, the Milky Way.
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A new age of complexity was
dawning in the universe.
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Now, there were stars
of different sizes,
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and different colours.
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And crucially new bodies had appeared.
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Planets.
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Places where the rich chemical elements
built by previous generations of stars
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could finally find a home.
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Countless billions of stars
have come and gone
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since those first giants
illuminated the darkness.
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Each enriching the universe
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with the material
out of which the next generation formed.
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Blue stars and white stars,
single stars, double stars,
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even triple star systems orbiting
around each other.
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The conditions were now right
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for those stars to drive the universe
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into a new and profound age
of complexity.
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Our Sun was formed from the ashes
of generations of ancestors.
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Just one small star in a galaxy
of billions of brilliant gods.
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For the first million years of its life,
the Sun was virtually alone,
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wreathed in clouds of gas and dust.
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The dust slowly clumped together...
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forming clusters the size of pebbles.
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Then, boulders.
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And finally...
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planets.
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But the planets were lifeless rocks.
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Only the Sun had the power
to turn them into worlds.
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Some were too far away from the Sun.
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Ice giants,
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frozen, seemingly into infertility.
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Others formed too close to the Sun,
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seared by a relentless light.
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They became scorched desert worlds.
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But there was a planet
in the Sun's family
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that, quite by chance, formed
neither too close nor too far away.
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An Arcadia, where our star could
breathe life into dust.
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The planets are just the leftovers
from the formation of stars.
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Debris, if you like.
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They're just little specks orbiting
around those magnificent flames.
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But the planets are also
the places in the universe
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where gravity has concentrated
the heavy elements built
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by previous generations of stars.
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And that makes the planets the canvas
on which the stars can create.
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"The canvas on which the stars can
create." What do I mean by that?
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Well, just look around.
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Everywhere you look on Earth
there is complexity.
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00:30:32,600 --> 00:30:37,120
Not only mountains and rivers,
but living things, animals and plants,
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human beings, human civilisation,
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the most complex thing we know of
anywhere in the universe.
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So, you have to ask yourself
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how can it be
that such complexity can emerge
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completely naturally in the universe?
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Well the answer, in fact was
known in the 19th century
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and it comes from the science
of thermodynamics.
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00:31:07,800 --> 00:31:08,960
In the 19th century,
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00:31:09,040 --> 00:31:11,480
people were interested
in the efficiency of steam engines,
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00:31:11,560 --> 00:31:16,040
and steam engines are, after all,
the machines that powered the factories
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00:31:16,120 --> 00:31:19,600
that allowed people to build
increasingly complex things.
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00:31:20,080 --> 00:31:24,160
And it turns out that the only thing
that matters for a steam engine,
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the thing
that determines its efficiency,
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00:31:26,400 --> 00:31:30,000
the thing that allows it
to do work and build things
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00:31:30,080 --> 00:31:33,600
is the temperature difference
between the fire,
255
00:31:33,680 --> 00:31:36,520
the furnace
at the heart of the steam engine,
256
00:31:36,600 --> 00:31:39,800
and the cold environment surrounding it.
257
00:31:41,960 --> 00:31:46,800
In the universe, the stars are
hot spots in a cold sky.
258
00:31:46,880 --> 00:31:52,080
We are sitting, in a very real sense,
inside a giant steam engine,
259
00:31:52,160 --> 00:31:54,680
powered by the furnace of the Sun.
260
00:31:56,360 --> 00:31:58,280
And it's in that sense
261
00:31:58,360 --> 00:32:03,480
that the stars are the creators
of complexity in the universe.
262
00:32:07,520 --> 00:32:11,160
But creating complexity is a subtle art.
263
00:32:14,120 --> 00:32:19,560
You need an engine, in this case a star,
that's not too wild and flashy.
264
00:32:24,440 --> 00:32:29,120
A star which is
consistent enough for long enough
265
00:32:29,200 --> 00:32:31,320
to kindle the sparks of life,
266
00:32:37,240 --> 00:32:41,400
and allow those sparks
to flicker and flourish.
267
00:32:54,360 --> 00:32:59,760
The most important property of a star,
if it's to nurture a civilisation...
268
00:33:01,800 --> 00:33:05,080
is magnificent dependability.
269
00:33:30,040 --> 00:33:33,920
No one knows exactly
how life on Earth emerged.
270
00:33:41,120 --> 00:33:44,720
But what we do know is
that at some point
271
00:33:44,800 --> 00:33:50,240
primitive cells living in the ocean
began using the Sun's energy
272
00:33:50,320 --> 00:33:53,640
to power life-giving chemical reactions.
273
00:33:56,240 --> 00:34:01,440
These cells formed a bridge
between Earth and Sun.
274
00:34:03,480 --> 00:34:07,760
Delicate engines
which harness the fires of our star,
275
00:34:09,480 --> 00:34:15,240
using sunlight to turn
carbon dioxide and water into food.
276
00:34:21,920 --> 00:34:28,560
This process, known as photosynthesis,
unleashed the Sun's creative power,
277
00:34:42,760 --> 00:34:46,040
and drove the evolution of complexity.
278
00:34:54,720 --> 00:34:56,640
From primitive bacteria,
279
00:34:57,680 --> 00:35:00,480
to plants and trees...
280
00:35:12,840 --> 00:35:16,880
and ultimately, to you and me.
281
00:35:20,840 --> 00:35:22,560
You know, photosynthesis is a process
282
00:35:22,640 --> 00:35:25,120
that's very easy to describe in words.
283
00:35:25,680 --> 00:35:27,640
The plants take energy from the Sun,
284
00:35:28,760 --> 00:35:32,440
then use it to react carbon dioxide
and water together
285
00:35:32,520 --> 00:35:35,920
to make sugars
and a waste product, oxygen.
286
00:35:36,000 --> 00:35:39,360
Really easy to say.
Very difficult to do.
287
00:35:39,440 --> 00:35:42,920
There's a part
of that photosynthetic machinery
288
00:35:43,000 --> 00:35:44,640
in everything you see here.
289
00:35:44,720 --> 00:35:47,600
Every plant on the planet has
got Photosystem II.
290
00:35:47,680 --> 00:35:52,840
It's comprised of 46,630 atoms
291
00:35:52,920 --> 00:35:56,480
all working together
in an intricate machine.
292
00:35:56,600 --> 00:36:00,440
Very efficient.
It took billions of years of evolution.
293
00:36:01,080 --> 00:36:02,440
Then we eat the plants,
294
00:36:02,520 --> 00:36:05,120
or we eat something
that's eaten the plants
295
00:36:05,200 --> 00:36:07,760
and we do the reverse reaction.
296
00:36:07,840 --> 00:36:12,440
We take those sugars and we breathe in
that waste product, oxygen.
297
00:36:12,520 --> 00:36:14,680
React them together,
release a bit of energy,
298
00:36:14,760 --> 00:36:17,200
a bit of the stored sunlight
if you like,
299
00:36:17,280 --> 00:36:22,920
and we use that energy to maintain
our structure, to grow, to live.
300
00:36:30,520 --> 00:36:34,120
Trillions of stars have existed
since the universe began.
301
00:36:39,120 --> 00:36:43,680
But ours has nurtured
that most miraculous thing,
302
00:36:45,280 --> 00:36:46,440
life.
303
00:36:49,960 --> 00:36:54,480
And that makes the Sun
a truly remarkable star.
304
00:37:03,160 --> 00:37:06,040
That is the only star
we know of anywhere
305
00:37:06,120 --> 00:37:10,720
where there are collections of atoms
in orbit around it, you and me,
306
00:37:10,800 --> 00:37:15,080
that have named it The Sun. Our Sun.
307
00:37:15,160 --> 00:37:18,880
We worshipped it, deified it
since the dawn of history.
308
00:37:18,960 --> 00:37:22,200
In fact, it's been argued
that the Sun lies at the foundation
309
00:37:22,280 --> 00:37:26,680
of all religion, and there may be
some truth in that.
310
00:37:26,760 --> 00:37:29,800
In fact, I think
there is a deep truth in that
311
00:37:29,880 --> 00:37:32,520
because we all owe our existence,
312
00:37:32,600 --> 00:37:37,000
this brief time we have
in the universe to that star.
313
00:37:37,080 --> 00:37:40,400
In fact, in a deeper sense
to all the stars.
314
00:37:40,480 --> 00:37:45,800
We don't need to invent
imaginary gods to explain the universe.
315
00:37:45,880 --> 00:37:48,720
We can replace them with the real thing.
316
00:38:02,600 --> 00:38:04,160
Everyone we love.
317
00:38:09,880 --> 00:38:12,120
Everything we value.
318
00:38:15,040 --> 00:38:19,720
Our supreme accomplishments
as a civilisation...
319
00:38:23,480 --> 00:38:26,400
were created and crafted...
320
00:38:30,080 --> 00:38:31,360
by stars.
321
00:38:51,240 --> 00:38:55,480
There are over 200 billion stars
in our galaxy.
322
00:39:00,520 --> 00:39:05,080
And there are two trillion galaxies
in the observable universe.
323
00:39:14,480 --> 00:39:16,840
We're living in the age of stars.
324
00:39:27,760 --> 00:39:31,120
An era of light and life in the cosmos.
325
00:39:37,280 --> 00:39:39,920
From our fleeting human perspective,
326
00:39:40,720 --> 00:39:42,800
stars seem eternal.
327
00:40:02,680 --> 00:40:06,520
But even gods are not immortal.
328
00:40:10,840 --> 00:40:12,720
Where there is light,
329
00:40:15,320 --> 00:40:16,760
there is darkness.
330
00:40:21,880 --> 00:40:23,640
Stars are creators,
331
00:40:29,560 --> 00:40:32,920
but they can be jealous guardians
of their creations.
332
00:40:38,320 --> 00:40:43,360
Many smaller stars don't die
in spectacular explosions.
333
00:40:45,200 --> 00:40:49,800
Instead, they slowly fade away.
334
00:40:51,680 --> 00:40:55,600
They hang on
to the precious elements they made,
335
00:40:57,720 --> 00:40:59,480
becoming fossil stars.
336
00:41:04,040 --> 00:41:06,720
And as more fossils litter the universe,
337
00:41:09,400 --> 00:41:13,040
more life giving elements
remain locked away,
338
00:41:15,720 --> 00:41:17,960
starving the cosmos
339
00:41:18,040 --> 00:41:21,960
of the material needed to make
new generations of stars.
340
00:41:39,880 --> 00:41:42,840
The age of stars may seem infinite,
341
00:41:45,120 --> 00:41:46,640
but it had a beginning,
342
00:41:48,400 --> 00:41:50,880
and it will also have an end.
343
00:41:54,680 --> 00:41:57,600
Imagine a timeline of the universe
344
00:41:57,680 --> 00:42:00,640
and imagine that this is
the origin of the universe,
345
00:42:00,720 --> 00:42:03,520
the big bang 13.8 billion years ago.
346
00:42:04,240 --> 00:42:08,040
After 100 million years or so,
the first stars formed.
347
00:42:08,120 --> 00:42:13,120
On this scale, one centimetre is
about 20 million years.
348
00:42:13,200 --> 00:42:17,800
After four billion years the peak rate
of star formation occurred.
349
00:42:17,880 --> 00:42:21,360
The maximum number
of new stars were born.
350
00:42:21,440 --> 00:42:26,120
After nine billion years,
our sun was born.
351
00:42:26,960 --> 00:42:31,560
And, today, we stand
13.8 billion years later,
352
00:42:31,640 --> 00:42:34,680
about halfway through
the lifetime of our sun.
353
00:42:35,600 --> 00:42:38,160
Now, in about five billion years' time,
354
00:42:38,240 --> 00:42:41,600
our sun will die
but new stars will be born,
355
00:42:42,200 --> 00:42:44,600
and many of the older stars
in the universe,
356
00:42:44,680 --> 00:42:47,800
the smaller stars, will
continue to shine.
357
00:42:47,880 --> 00:42:52,440
In fact, we think that the last star
will cease to shine,
358
00:42:52,520 --> 00:42:57,120
the universe will go dark,
in around ten trillion years.
359
00:42:58,760 --> 00:43:01,760
On this scale,
that's about 5000 metres away
360
00:43:01,840 --> 00:43:03,520
from the big bang.
361
00:43:04,040 --> 00:43:05,600
But that's not the end of the universe.
362
00:43:05,680 --> 00:43:11,080
As far as we know, the universe will
continue expanding forever.
363
00:43:11,600 --> 00:43:16,760
And so, the age of starlight is
the briefest moment of time
364
00:43:16,840 --> 00:43:19,000
in the infinite history of the universe.
365
00:43:19,080 --> 00:43:24,480
The age of darkness will go on
and on and on.
366
00:43:31,160 --> 00:43:34,120
Stars won't just disappear, of course.
367
00:43:37,040 --> 00:43:39,920
They'll be here for aeons to come.
368
00:43:43,480 --> 00:43:45,720
But over time,
369
00:43:45,800 --> 00:43:51,720
the universe will grow darker,
colder and emptier.
370
00:44:02,160 --> 00:44:03,920
There are stars around today
371
00:44:04,000 --> 00:44:07,800
that existed close to the beginning
of the age of stars.
372
00:44:16,480 --> 00:44:20,280
And some of them will
also witness the end.
373
00:44:24,920 --> 00:44:28,160
They're the longest-lived stars
in the universe.
374
00:44:30,080 --> 00:44:31,360
Red Dwarfs.
375
00:44:39,960 --> 00:44:42,720
Trappist-1 is one of these ancients.
376
00:44:50,000 --> 00:44:53,280
It's already more than
seven billion years old.
377
00:44:54,720 --> 00:44:56,880
Almost twice as old as our sun.
378
00:45:06,520 --> 00:45:09,920
But only around a tenth of the size,
379
00:45:15,920 --> 00:45:18,760
and less than one percent as bright.
380
00:45:22,720 --> 00:45:24,360
It's a cool star.
381
00:45:26,160 --> 00:45:27,680
Slow burning.
382
00:45:33,720 --> 00:45:36,800
And that is the secret of its longevity.
383
00:45:41,880 --> 00:45:43,600
Because they burn slowly,
384
00:45:44,960 --> 00:45:48,080
Red Dwarfs live for a very long time,
385
00:45:54,880 --> 00:45:58,240
far longer than any other star.
386
00:46:04,120 --> 00:46:07,680
Like the sun, Trappist-1 has
its own planets.
387
00:46:09,840 --> 00:46:11,880
Seven rocky worlds,
388
00:46:14,760 --> 00:46:17,200
each roughly the size of Earth.
389
00:46:21,680 --> 00:46:26,080
Some may have atmospheres,
and even oceans.
390
00:46:35,320 --> 00:46:37,840
But there the similarity ends,
391
00:46:49,800 --> 00:46:52,200
because these are strange worlds.
392
00:46:55,240 --> 00:46:58,960
Every one of these planets
is locked in its orbit
393
00:47:01,080 --> 00:47:03,760
one side facing Trappist-1,
394
00:47:05,760 --> 00:47:07,680
the other side frozen,
395
00:47:07,760 --> 00:47:11,760
permanently exposed
to the cold void of space.
396
00:47:24,040 --> 00:47:27,880
If you could stand on the surface
of one of these ancient worlds,
397
00:47:34,520 --> 00:47:37,000
as the aeons passed,
398
00:47:41,160 --> 00:47:46,040
you could watch the future
of the cosmos slowly unfold.
399
00:47:56,240 --> 00:48:01,240
And, one day,
five billion years from now,
400
00:48:03,720 --> 00:48:07,080
you'd see our sun flicker
401
00:48:08,360 --> 00:48:11,720
and fade away forever.
402
00:48:40,120 --> 00:48:43,240
The death of our sun will
probably go unremarked.
403
00:48:46,000 --> 00:48:47,960
I doubt that we'll be around to see it.
404
00:48:48,040 --> 00:48:51,920
Maybe some alien astronomer,
on a world far away
405
00:48:52,000 --> 00:48:53,800
across the milky way, will see it
406
00:48:53,880 --> 00:48:55,960
through the end of their telescope
407
00:48:56,040 --> 00:48:57,936
but I don't think
they'll give it a second thought.
408
00:48:57,960 --> 00:49:02,640
I mean, we've seen hundreds of stars die
and we don't give them a second thought.
409
00:49:02,720 --> 00:49:07,640
But, I think the death of our sun will
matter here, locally,
410
00:49:07,720 --> 00:49:10,480
in this little corner of the galaxy,
411
00:49:10,560 --> 00:49:13,480
because it will mark the end
of a glorious time
412
00:49:13,560 --> 00:49:15,000
in the history of our galaxy,
413
00:49:15,160 --> 00:49:19,040
where meaning,
where science and literature
414
00:49:19,120 --> 00:49:22,320
and art and poetry
and music existed here.
415
00:49:22,960 --> 00:49:24,240
And that does matter.
416
00:49:28,240 --> 00:49:30,520
Why does meaning have to be eternal?
417
00:49:30,600 --> 00:49:34,840
It's the fragility of our lives
that makes them valuable.
418
00:49:40,200 --> 00:49:43,560
I think the wonderful thing is
that our star has
419
00:49:43,640 --> 00:49:47,880
taken the laws of nature,
here on this planet,
420
00:49:47,960 --> 00:49:51,680
and crafted such
a magnificent expression of them.
421
00:49:51,760 --> 00:49:53,440
You and me,
422
00:49:54,960 --> 00:49:56,200
and all this.
423
00:50:24,680 --> 00:50:29,840
Stars like Trappist-I will linger on
long after the death of our sun.
424
00:50:37,960 --> 00:50:41,400
We will never know the name
of the last star.
425
00:50:49,080 --> 00:50:50,480
But we know
426
00:50:51,520 --> 00:50:53,680
that the last star to shine
427
00:50:55,560 --> 00:50:57,000
will be a Red Dwarf.
428
00:51:04,240 --> 00:51:06,840
The last star will slowly cool...
429
00:51:10,800 --> 00:51:12,080
and fade away.
430
00:51:26,080 --> 00:51:28,680
With its passing
the universe will become,
431
00:51:29,520 --> 00:51:32,240
once again, a void,
432
00:51:37,320 --> 00:51:38,720
without light,
433
00:51:41,120 --> 00:51:42,240
or life,
434
00:51:45,640 --> 00:51:46,800
or meaning.
435
00:52:05,720 --> 00:52:07,680
The stars illuminate the universe
436
00:52:07,760 --> 00:52:10,200
and create
its most intricate structures.
437
00:52:14,600 --> 00:52:17,280
And, one day, they will all be gone.
438
00:52:21,360 --> 00:52:24,960
The stars are gods,
but they're mortal gods.
439
00:52:25,360 --> 00:52:28,600
And, when that time comes
and the last stars have faded,
440
00:52:28,680 --> 00:52:34,320
and all possibility of life and meaning
in the universe has faded with them,
441
00:52:34,400 --> 00:52:37,520
they will have left
the most profound legacy.
442
00:52:37,600 --> 00:52:42,040
Because, for a moment
in the long history of the universe,
443
00:52:42,120 --> 00:52:45,120
the stars illuminated the dark,
444
00:52:45,200 --> 00:52:48,280
and allowed us to illuminate it, too.
445
00:53:22,560 --> 00:53:26,920
We want to study the sun
because it teaches us a lot about stars.
446
00:53:27,000 --> 00:53:30,960
It teaches us a lot about all the other
millions and billions of stars
447
00:53:31,040 --> 00:53:32,680
in our galaxy and beyond.
448
00:53:40,960 --> 00:53:42,320
There was a moment,
449
00:53:42,400 --> 00:53:44,096
when we were putting
the spacecraft together,
450
00:53:44,120 --> 00:53:46,096
that I just took a moment
and looked at the spacecraft
451
00:53:46,120 --> 00:53:47,360
and realised,
452
00:53:47,440 --> 00:53:49,760
this is going into a star,
453
00:53:50,440 --> 00:53:53,960
and to realise how special it was
454
00:53:54,240 --> 00:53:56,640
to be able to have worked on this,
455
00:53:56,720 --> 00:54:00,680
and that humanity decided this was
something we wanted to do.
456
00:54:01,480 --> 00:54:03,600
- Minus 30.
- Status check.
457
00:54:03,920 --> 00:54:06,280
- Pro delta.
- Go PSP.
458
00:54:06,840 --> 00:54:08,000
Minus 15.
459
00:54:08,160 --> 00:54:10,760
Launch night,
I was sick to my stomach.
460
00:54:11,200 --> 00:54:16,640
Five, four, three, two,
one, zero.
461
00:54:17,520 --> 00:54:19,600
Lift-off of the mighty Delta IV...
462
00:54:19,680 --> 00:54:23,160
...Heavy Rocket
with NASA's Parker Solar Probe.
463
00:54:23,240 --> 00:54:25,480
There we go.
464
00:54:25,560 --> 00:54:27,000
The spacecraft is the first
465
00:54:27,080 --> 00:54:29,080
that NASA has named
after a living person,
466
00:54:29,480 --> 00:54:31,280
because Eugene Parker is
467
00:54:31,360 --> 00:54:33,720
really such, you know,
an eminent physicist in our field.
468
00:54:36,080 --> 00:54:39,040
The Delta IV Heavy
is a very slow rocket
469
00:54:39,120 --> 00:54:41,120
compared to the other launches
I've seen,
470
00:54:41,240 --> 00:54:43,120
so I just saw fireballs,
471
00:54:43,200 --> 00:54:46,160
and was very,
very frightened for a while.
472
00:54:46,240 --> 00:54:47,840
Twenty-five seconds
into flight.
473
00:54:50,200 --> 00:54:52,760
Temp and pressures continue to look good
on all three boosters.
474
00:54:52,920 --> 00:54:56,720
Then realising that this was all okay
as it slowly made its way up
475
00:54:56,800 --> 00:54:58,080
into the sky.
476
00:54:59,160 --> 00:55:00,840
Now 50 seconds into flight.
477
00:55:07,360 --> 00:55:10,280
Parker Solar Probe is
so revolutionary
478
00:55:10,360 --> 00:55:13,920
because it's the first time that we're
actually going in to touch the sun.
479
00:55:15,520 --> 00:55:17,600
We're going 94 % of the way
480
00:55:17,680 --> 00:55:19,480
from the Earth to the sun
481
00:55:19,560 --> 00:55:23,400
to actually experience the solar corona,
the sun's atmosphere.
482
00:55:24,640 --> 00:55:26,880
I think, at closest approach,
483
00:55:26,960 --> 00:55:30,000
it'll be about eight solar radii
from the Sun
484
00:55:30,080 --> 00:55:32,920
which is just mind-blowingly close.
485
00:55:36,600 --> 00:55:39,720
So, we were expecting
things to be very hot,
486
00:55:39,840 --> 00:55:42,800
over 2,500 Fahrenheit,
487
00:55:42,880 --> 00:55:46,080
but in a soup
of a million degree plasma.
488
00:55:50,560 --> 00:55:52,136
That's a real challenge
for the spacecraft
489
00:55:52,160 --> 00:55:53,640
to survive that environment.
490
00:55:53,880 --> 00:55:54,920
So, in order to do that,
491
00:55:55,000 --> 00:55:57,920
there's a very large heat shield
on the front of the spacecraft
492
00:55:58,000 --> 00:56:00,440
which protects
the majority of the instruments
493
00:56:00,520 --> 00:56:02,720
which are sat behind
on the spacecraft body.
494
00:56:05,040 --> 00:56:07,680
What makes
Parker so great is the fact
495
00:56:07,760 --> 00:56:09,320
that it has a set of instruments
496
00:56:09,400 --> 00:56:12,480
that work together
in order to look in all directions
497
00:56:12,560 --> 00:56:16,000
in order to solve those big mysteries
about the solar wind.
498
00:56:23,320 --> 00:56:27,080
The solar corona has been mysterious
to us since we've known about it,
499
00:56:27,160 --> 00:56:28,640
so it's a very strange thing.
500
00:56:28,720 --> 00:56:32,520
The surface of the sun is
sort of 6,000 degrees
501
00:56:32,600 --> 00:56:35,160
and then, above that, you have
this very thin atmosphere
502
00:56:35,240 --> 00:56:36,640
that's a million degrees.
503
00:56:36,720 --> 00:56:37,840
Super-hot.
504
00:56:37,920 --> 00:56:39,840
And the way that's heated,
505
00:56:39,920 --> 00:56:42,360
we know it has something to do
with magnetic fields
506
00:56:42,440 --> 00:56:44,520
but we don't know exactly how it works.
507
00:56:44,640 --> 00:56:46,640
That's where
the solar wind is generated.
508
00:56:46,720 --> 00:56:48,680
We don't know quite exactly
how that works either.
509
00:56:51,080 --> 00:56:54,680
Other things that have
come out of this are
510
00:56:54,760 --> 00:56:56,480
coronal mass ejections.
511
00:56:56,560 --> 00:56:59,080
When we originally did the proposal,
512
00:56:59,160 --> 00:57:02,520
we were thinking that we would see five
in the entire seven-year mission,
513
00:57:02,600 --> 00:57:04,160
if we were lucky.
514
00:57:06,040 --> 00:57:08,840
We ended up seeing around
four to five in the first year.
515
00:57:10,640 --> 00:57:13,880
So, there has been just a total switch
516
00:57:13,960 --> 00:57:17,360
in terms of how active the sun is
517
00:57:17,440 --> 00:57:19,480
or what we classify
as coronal mass ejections.
518
00:57:19,560 --> 00:57:20,880
Maybe a little bit of both.
519
00:57:27,160 --> 00:57:30,400
It is a joy to see
all the data coming back.
520
00:57:30,480 --> 00:57:32,760
It's a joy to share it with others
521
00:57:32,840 --> 00:57:36,760
and to see them be as curious
as I have been for the last decade.
522
00:57:40,440 --> 00:57:42,320
So, Parker has just begun
its mission really,
523
00:57:42,400 --> 00:57:43,800
and it's already really started
524
00:57:43,880 --> 00:57:46,680
to truly transform our understanding
for how the sun works.
42648
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