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Subs by KalEl82
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Our universe is an enigma,
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an endless, inexhaustible paradox.
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It's largely...
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a dark, cold, and lifeless ocean.
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But within this ocean,
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there are islands...
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blazing with light.
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Galaxies, trillions of them,
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each one,
home to hundreds of billions of stars,
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and around many of these stars,
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there are planets,
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alien worlds,
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each incomprehensibly strange.
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There are trillions
of planets in our universe
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and one of them
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nurtured beings capable of
contemplating this cosmic drama,
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miraculously improbable,
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brief candles flickering
against the eternal night.
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As darkness begins to fall,
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if you know that
all those points of light
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that appear one by one
in the darkening sky are distant suns,
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then it's impossible
not to be overwhelmed
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at the sheer scale
and majesty of it all.
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The universe
is infinite in all directions,
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and terrifying in all directions.
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But if you can overcome your fear,
then questions arise.
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And surely the most
profound question of all is,
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"How did all this come to be here?"
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That's a question
that's defined much of human history.
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But it's only in the last century or so
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that we've had the intellectual
and technical tools
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to interrogate nature directly
in search of an answer.
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And we've found
that it looks, for all the world,
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like there was a first moment in time,
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a beginning to the universe
13.8 billion years ago, the Big Bang.
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For all the world, but not quite,
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because we've begun to suspect
that there's more to it,
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and we've embarked on
a heroic quest to search for
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and to explore the time before the dawn.
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I can see
everything quite clearly. The light...
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It has a stark beauty all its own.
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# See me when I float like a dove
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# Skies above...
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Magnificent desolation.
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- Beautiful view.
- Isn't that something?
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# Take me away #
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For all the people back on Earth,
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the crew of Apollo 8
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has a message that
we would like to send to you.
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In the beginning, God created
the heaven and the earth.
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And the earth was without form and void,
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and darkness was
upon the face of the deep.
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And God said, "Let there be light",
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and there was light.
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And God saw the light that it was good.
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Since we first became
conscious of ourselves,
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we've looked to the heavens,
to those mysterious lights...
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searching for answers.
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What is the universe?
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How did it come to be?
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And what is our place in the cosmos?
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We sometimes doubt
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the creation stories
that our ancestors told.
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But those ancient myths
conceal a profound truth.
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The clues to the origins of everything
can be found out there...
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in light which ripples to us
from beyond the stars.
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If we're going to dare to know
about the origin of the universe,
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then we have to have some evidence.
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And the connection we have
with the deep past is light.
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See, light travels very slowly
on the universal scale,
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only 186,000 miles a second.
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It takes light eight minutes
to journey from the sun to the earth.
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It takes four years for light
to journey from the next nearest star.
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And that means we see that star
as it was four years in the past.
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So, the further out
into the universe we look,
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the further back in time we look.
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And because we can look
way out into the distant universe,
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we can look back towards
the beginning of time.
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Go ahead, Charlie.
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Okay,
we have a go for release,
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and we're gonna be a minute late.
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Okay, Charlie.
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In the quest to find the origin
of the universe,
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we need a time machine.
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This is Discovery.
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We concur, Charlie.
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A telescope so powerful,
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that can peer out
so far into the universe,
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that it can capture
the most ancient light...
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The telescope's released.
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...and carry us back...
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towards the dawn of time.
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Okay, Charlie.
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The Hubble Space Telescope
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has taken us on
an odyssey through the universe,
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revealing its gods...
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and monsters.
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Our universe is a place of beauty...
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and terror.
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Hubble has shown us
visions of sublime creation...
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and images of awesome destruction,
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illuminating our journey
backwards in time...
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towards the dawn.
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The Orion Nebula, a stellar nursery,
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clouds of gas nurturing newborn stars
in the Milky Way.
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An image brought to us by light
that left the nebula 1 ,300 years ago.
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The Pillars of Creation,
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towering, delicate structures,
light years tall,
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7,000 years ago.
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The Andromeda galaxy,
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a glittering island of a trillion suns,
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2.5 million years ago.
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A cosmic rose,
galaxies colliding in a celestial dance,
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300 million years ago.
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But Hubble's voyage
has taken us even further out
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into the uncharted ocean of space,
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ever deeper into the darkness,
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glimpsing countless ancient
and faraway galaxies.
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Wild, and primitive shoals of stars,
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lighting the way
to their primordial past,
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until, finally, Hubble approached
the farthest shore,
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a galaxy near the dawn of time.
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This is a galaxy called GN-z11 ,
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and it is one of the most
distant galaxies we've ever seen.
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This is light from some
of the first stars in the universe.
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It began its journey only
400 million years after the Big Bang,
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and it's taken 13.4 billion years
to reach us.
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When you think about that, this light
journeyed through the universe,
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and after nine billion years
of its journey, the earth formed.
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And then, during the whole history
of our planet,
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it completed the last third of
its journey and entered our telescopes.
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So, this is an image
from the edge of time.
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GN-z1 I was one
of the very first galaxies,
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formed at a time when the universe
itself was taking shape,
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shortly after the Big Bang.
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GN-z1 I was a strange galaxy
by today's standards.
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Twenty-five times
smaller than the Milky Way,
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but filled with enormous, violent stars.
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Lurking alongside these volatile giants,
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there were other things,
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delicate objects struggling
in the maelstrom,
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some of the first planets
in the universe.
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These were strange, primordial worlds,
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and over the horizon
of one of them, a sun rose,
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marking a new chapter
in the history of the universe,
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the beginnings of a relationship
between stars and planets...
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that would, billions of years later,
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on a faraway world,
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lead to the origin of life.
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Now, we don't know when or where
the first dawn broke in the universe.
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But what we do know is that
the first dawn was not the first moment.
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The stars and planets
had to come from somewhere.
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So, the first dawn was
preceded by long, dark night.
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Astronomers call this era
the cosmic dark ages.
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If we continue to journey back in time,
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we'd see shadows
fall across the universe.
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The galaxies would disappear.
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The first primitive stars
would be extinguished...
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one by one...
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and darkness truly would
be upon the face of the deep.
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Here in the impenetrable gloom
of the cosmic dark ages,
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our quest to understand
the origins of the universe...
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would seem to end.
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So, how can we peer
into the cosmic dark ages
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to explore the origin of the universe?
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Well, perhaps counter-intuitively,
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the light from the stars
can still guide us
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because that starlight has been
travelling across the universe
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for millions or even billions
of years to reach us,
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and information about the way
the universe has changed and evolved
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becomes imprinted in that starlight.
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The stars have illuminated
our voyage through time.
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But their light can't guide us
directly across the dark ages.
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Instead, their light can be used
to build maps of the universe
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in space and time...
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that allow us to navigate...
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towards the moment of creation.
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And the most valuable light of all
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comes from very particular stars in
the spectacular swansong of their lives.
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Stars exist
in a permanent state of conflict
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because the force of gravity
is relentless.
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Left to its own devices, it will crush
anything and everything without limit.
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But fortunately,
other forces come into play.
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As a star collapses, its core heats up
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and turns into
a giant nuclear fusion reactor.
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Hydrogen is converted into helium
that releases energy
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which creates a pressure
which holds the star up.
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But stars like our sun
burn hundreds of millions
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of tons of hydrogen
into helium every second.
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And although they are big,
they're not infinite in size.
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Stars, just like human beings,
have a lifetime.
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They are subject
to the relentless march of time.
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And for stars like our sun,
the collapse continues
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until it produces a new
and exotic type of star
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known as a white dwarf.
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White dwarfs are strange beasts,
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the fading remains of stars,
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super dense, planetary-sized cores,
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usually composed entirely
of carbon and oxygen.
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Stars that were once a million times
the size of our planet,
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crushed to the size of the earth,
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subjecting the carbon
to extreme pressures,
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and making white dwarfs,
in effect, stellar diamonds.
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These diamond stars
are critically balanced,
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able to resist the relentless
inwards pull of gravity.
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But only just.
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And that can make them
ticking time bombs.
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In 2018, Hubble was in orbit.
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The telescope focused
on a galaxy far, far away,
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hunting for a distant white dwarf
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that we knew was coming to the end
of its extraordinary life.
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For millions of years,
the white dwarf had remained hidden,
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locked in orbit around
a much biggest star,
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a red giant.
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As they circled each other,
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the white dwarf's gravity drew in
gas and plasma from the red giant.
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The mass of the white dwarf increased...
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until it approached a critical limit...
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known as the Chandrasekhar mass...
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and surpassed it...
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triggering a colossal
thermonuclear reaction.
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The white dwarf detonated...
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in a gigantic explosion
called a supernova
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that millions of light years away,
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was detected by Hubble.
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That white dwarf star,
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or to be more precise, the supernova
that it became, has a name.
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It's called SN 2018gv.
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And even though it is
70 million light years away,
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it is so bright
that we could make a movie on it.
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I mean, imagine now, this is a star
the size of a planet
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ending its life with a flash of light
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that's as bright as five billion suns.
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Now, although supernova like these
only shine for a few days,
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they cast a profound light
out across the universe.
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We've given a name to
the sorts of supernova Hubble saw.
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They're called Type 1 a supernovae
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and they're common enough to allow us
to map the evolution of the universe.
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Type 1 a supernovae
really are nature's gift to us
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because they all explode
in the same way.
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That means that they all shine
with the same brightness.
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And that means that if we see one
that's dimmer, it must be farther away.
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And that allows us to measure
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the distance to the galaxy
that contains the supernova.
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And because they shine so bright,
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we can see them
tens of billions of light years away.
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That means that we can measure
the distance to galaxies
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all the way out towards the edge
of the observable universe.
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But there's other information
encoded in the light.
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When we look at the light
from distant supernova explosions,
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00:28:37,761 --> 00:28:41,880
we see something very interesting,
and very surprising,
253
00:28:41,961 --> 00:28:44,320
because the light
from every single supernova
254
00:28:44,401 --> 00:28:48,080
that's not in our neighbourhood
is redder that it should be.
255
00:28:48,161 --> 00:28:51,080
The further away the supernova,
the redder the light.
256
00:28:51,161 --> 00:28:52,480
It's called a redshift.
257
00:28:52,841 --> 00:28:55,240
Now, light has a wavelength,
258
00:28:55,321 --> 00:28:59,040
and the longer the wavelength,
the redder the light.
259
00:28:59,121 --> 00:29:00,680
So, the explanation is that,
260
00:29:00,761 --> 00:29:05,000
during the time the light has been
travelling from the supernova to us,
261
00:29:05,081 --> 00:29:09,960
space itself has been stretching,
and that stretched the light.
262
00:29:10,521 --> 00:29:14,360
And that means that
the universe is expanding.
263
00:29:18,481 --> 00:29:22,760
In our quest to find the origin
of the universe, this is a vital clue.
264
00:29:25,281 --> 00:29:27,760
Because if the universe
is expanding today,
265
00:29:28,841 --> 00:29:32,200
then, tomorrow,
everything will be farther apart.
266
00:29:37,201 --> 00:29:42,080
And it follows that, yesterday,
everything was closer together.
267
00:29:44,241 --> 00:29:46,600
So, if we want to understand
how it all began,
268
00:29:50,281 --> 00:29:52,160
we have to wind back time
269
00:29:55,081 --> 00:29:57,320
through billions of yesterdays.
270
00:30:01,961 --> 00:30:05,440
We have to go back to a time
before the earth and the sun,
271
00:30:17,321 --> 00:30:20,680
to a time before the galaxies,
272
00:30:26,441 --> 00:30:30,440
and all the while,
the universe is shrinking,
273
00:30:33,281 --> 00:30:39,280
getting ever smaller,
denser, and hotter,
274
00:30:40,521 --> 00:30:45,160
until we arrive at the most famous
moment in the history of the universe.
275
00:31:10,001 --> 00:31:12,600
Our universe is a place
of infinite variety.
276
00:31:20,721 --> 00:31:23,600
There are galaxies of exquisite beauty,
277
00:31:27,761 --> 00:31:30,520
stars of stupendous power,
278
00:31:34,961 --> 00:31:40,000
and planets...
countless brave new worlds.
279
00:31:57,001 --> 00:31:59,520
Galaxies, stars, and planets
280
00:31:59,601 --> 00:32:02,840
are the things that make
our universe remarkable.
281
00:32:09,441 --> 00:32:13,560
They are the things that make it
more than a barren expanse.
282
00:32:22,521 --> 00:32:26,440
How did a universe of light and life
283
00:32:26,521 --> 00:32:30,440
emerge from the cataclysm
of the Big Bang?
284
00:32:35,401 --> 00:32:37,600
Unfortunately, we don't know.
285
00:32:37,681 --> 00:32:40,720
We don't even know
if the universe had a beginning.
286
00:32:40,801 --> 00:32:44,480
But we do know a great deal
about how the universe evolved
287
00:32:44,561 --> 00:32:48,000
from a very different state
a long time in the past.
288
00:32:48,081 --> 00:32:50,880
We know that 13.8 billion years ago,
289
00:32:50,961 --> 00:32:55,080
this space that I'm standing in now
and the space you're standing in now
290
00:32:55,161 --> 00:32:58,520
and all the space out to the edge
of the observable universe
291
00:32:58,601 --> 00:33:03,440
containing two trillion galaxies
was very hot and very dense,
292
00:33:03,521 --> 00:33:05,680
and has been expanding ever since.
293
00:33:06,161 --> 00:33:10,920
Now, that implies that way back,
everything was closer together,
294
00:33:11,001 --> 00:33:14,040
everything was contained
in a very small speck.
295
00:33:14,121 --> 00:33:16,600
But how small was that speck?
296
00:33:17,201 --> 00:33:18,760
How did it come to be?
297
00:33:19,121 --> 00:33:23,320
Well, we used to think
that the universe emerged in that state,
298
00:33:23,401 --> 00:33:26,040
very hot and very dense
at the beginning of time,
299
00:33:26,121 --> 00:33:28,840
and we used to call that the Big Bang.
300
00:33:28,921 --> 00:33:34,320
But now, we strongly suspect
that the universe existed before that.
301
00:33:34,401 --> 00:33:39,880
And in that sense, it is possible
to speak of a time before the Big Bang.
302
00:33:50,081 --> 00:33:53,840
So, what was the universe like
before the Big Bang?
303
00:33:58,361 --> 00:34:02,560
The first thing to say
is that it was very strange.
304
00:34:07,641 --> 00:34:11,440
There was no matter.
305
00:34:11,521 --> 00:34:14,960
All that existed was spacetime
306
00:34:15,041 --> 00:34:17,960
and energy, an ocean of energy,
307
00:34:19,201 --> 00:34:23,320
almost still, but gently rippling.
308
00:34:33,881 --> 00:34:35,280
Before the Big Bang,
309
00:34:35,361 --> 00:34:39,840
the universe was a cold,
alien, featureless place.
310
00:34:43,761 --> 00:34:48,200
Picture it as a near still ocean
of energy filling the void.
311
00:34:49,081 --> 00:34:51,320
Although it contained no structures,
312
00:34:51,401 --> 00:34:56,560
that energy did have an effect
on space. It caused it to stretch.
313
00:34:59,361 --> 00:35:02,000
Not the gentle expansion we see today,
314
00:35:02,081 --> 00:35:05,280
but unimaginably violent expansion.
315
00:35:05,361 --> 00:35:08,200
That expansion is known as inflation.
316
00:35:12,201 --> 00:35:17,480
Think of a speck,
a tiny, insignificant patch of space,
317
00:35:23,321 --> 00:35:27,880
insignificant, except that
many billions of years later,
318
00:35:28,561 --> 00:35:33,440
this speck would have grown to
become our entire observable universe.
319
00:35:36,881 --> 00:35:41,240
The speck expanded at a phenomenal rate,
320
00:35:41,321 --> 00:35:43,800
an exponential expansion...
321
00:35:47,001 --> 00:35:48,840
that lasted...
322
00:35:49,881 --> 00:35:55,480
just a few billion, billion, billion,
billionths of a second.
323
00:35:59,281 --> 00:36:01,800
Now, the speck continued to expand
324
00:36:01,881 --> 00:36:04,160
until it was about
the size of this cave.
325
00:36:04,241 --> 00:36:07,760
And then, inflation
drew rapidly to a close,
326
00:36:07,841 --> 00:36:11,080
and all the energy in that ocean
that was driving the expansion
327
00:36:11,161 --> 00:36:14,920
was dumped into space
and formed the ingredients
328
00:36:15,001 --> 00:36:18,040
of everything
in our observable universe.
329
00:36:18,121 --> 00:36:21,960
I mean, imagine that.
A space about this size
330
00:36:22,041 --> 00:36:26,280
filled with enough energy
to form two trillion galaxies.
331
00:36:27,321 --> 00:36:28,960
That's what we call the Big Bang.
332
00:36:39,041 --> 00:36:41,280
So the Big Bang was not,
333
00:36:41,361 --> 00:36:44,880
as we commonly imagine,
some kind of explosion.
334
00:36:47,881 --> 00:36:52,520
It was actually
a transformation of energy into matter.
335
00:36:59,801 --> 00:37:03,880
And the fossilised remains
of these momentous events,
336
00:37:03,961 --> 00:37:08,480
the memory of the rippling ocean
of energy that drove inflation
337
00:37:08,561 --> 00:37:11,680
became imprinted into our universe.
338
00:37:13,121 --> 00:37:17,560
In fact, these fossilised ripples
shaped our universe,
339
00:37:18,521 --> 00:37:23,680
influencing where each galaxy
and star emerged,
340
00:37:23,761 --> 00:37:26,880
each planet and moon.
341
00:37:31,161 --> 00:37:33,480
But how do we know all this?
342
00:37:36,921 --> 00:37:39,840
How do we know
that there was a Big Bang?
343
00:37:41,321 --> 00:37:43,320
How do we know there were
344
00:37:43,401 --> 00:37:47,040
ripples in an ocean of energy
before the Big Bang?
345
00:37:54,241 --> 00:37:55,760
The answer is...
346
00:37:58,481 --> 00:38:00,120
...that we've seen them.
347
00:38:52,681 --> 00:38:55,720
Planck scanned the entire cosmos
348
00:38:58,041 --> 00:38:59,600
looking for light.
349
00:39:10,841 --> 00:39:14,120
Not light from galaxies or stars,
350
00:39:16,961 --> 00:39:19,680
but light from the beginning of time.
351
00:39:48,121 --> 00:39:50,960
This is a photograph
of the distant past.
352
00:39:51,321 --> 00:39:53,360
It's the most ancient light
in the universe.
353
00:39:53,441 --> 00:39:58,400
This is light that's travelled for
almost 13.8 billion years to reach us.
354
00:39:58,921 --> 00:40:01,120
It's a photograph of the entire sky,
355
00:40:01,201 --> 00:40:05,480
a celestial sphere, if you like,
every direction that we can look,
356
00:40:05,561 --> 00:40:08,320
and it's been laid flat
so we can see it all.
357
00:40:09,121 --> 00:40:12,320
It's called the cosmic microwave
background radiation,
358
00:40:12,401 --> 00:40:14,680
and it's an almost featureless glow.
359
00:40:14,761 --> 00:40:18,160
There were no stars
and no galaxies in this universe.
360
00:40:18,961 --> 00:40:20,560
Now, you might ask the question,
361
00:40:20,641 --> 00:40:23,400
"Well, if there were
no stars and there were no galaxies,
362
00:40:23,481 --> 00:40:25,440
"then, where's the light coming from?"
363
00:40:25,521 --> 00:40:29,360
The answer is, the light
is coming from the universe itself.
364
00:40:29,441 --> 00:40:32,680
Because this is only a few hundred
thousand years after the Big Bang,
365
00:40:32,761 --> 00:40:35,040
so, the universe was hot.
366
00:40:35,121 --> 00:40:39,680
So, what you're seeing here
is the afterglow of the Big Bang.
367
00:40:55,641 --> 00:41:00,480
The most revealing thing
about this picture is the detail,
368
00:41:08,561 --> 00:41:09,880
the variation.
369
00:41:21,921 --> 00:41:23,360
This pattern is one of
370
00:41:23,441 --> 00:41:26,920
the most important discoveries
in all of human history
371
00:41:27,001 --> 00:41:30,120
because it represents
one of the necessary steps
372
00:41:30,201 --> 00:41:32,520
in the story of how we came to be here.
373
00:41:42,641 --> 00:41:46,880
See, that still ocean of energy
that drove the rapid expansion
374
00:41:46,961 --> 00:41:51,840
of space during inflation
could not be entirely still.
375
00:41:52,161 --> 00:41:54,240
There had to be ripples in the ocean.
376
00:41:54,321 --> 00:41:58,440
It's a consequence of the laws
of nature, as we understand them.
377
00:42:04,801 --> 00:42:08,600
And those ripples in the ocean
were imprinted into our universe
378
00:42:08,681 --> 00:42:12,760
through the Big Bang
that emerged as those areas
379
00:42:12,841 --> 00:42:16,080
of slightly different density
in the young universe.
380
00:42:17,961 --> 00:42:21,720
And then, as the universe
continued to expand and cool,
381
00:42:21,801 --> 00:42:24,480
the regions that were
slightly denser collapsed
382
00:42:24,561 --> 00:42:27,760
to form the first stars and galaxies.
383
00:42:28,641 --> 00:42:31,920
So, without those ripples,
we would not exist.
384
00:42:36,841 --> 00:42:40,640
But there's one more extraordinary thing
about these ripples.
385
00:42:41,841 --> 00:42:44,640
And that's the fact
that we predicted them
386
00:42:44,721 --> 00:42:47,440
before we knew they existed.
387
00:42:49,561 --> 00:42:53,880
And then, we ventured into space
to test our theory.
388
00:42:54,881 --> 00:42:59,600
Planck's observation of the afterglow
of the Big Bang is strong evidence
389
00:42:59,681 --> 00:43:02,640
for our outlandish creation saga,
390
00:43:04,441 --> 00:43:10,280
the story of the speck,
the ripples, and inflation.
391
00:43:16,081 --> 00:43:19,000
These ripples, then,
are the seeds of our creation,
392
00:43:19,081 --> 00:43:21,920
and we dared to guess that they exist
393
00:43:22,001 --> 00:43:24,880
from our vantage point here,
on a small planet
394
00:43:24,961 --> 00:43:29,240
13.8 billion years
after the moment of creation.
395
00:43:30,081 --> 00:43:35,280
And then, because we're scientists,
we decided to launch a spacecraft
396
00:43:35,361 --> 00:43:39,960
out into space, and capture
the oldest light in the universe.
397
00:43:40,041 --> 00:43:43,240
And we saw that our guess was correct.
398
00:43:44,001 --> 00:43:46,920
We dared to imagine
a time before the dawn,
399
00:43:47,001 --> 00:43:51,960
and we proved that
our creation story is not a myth.
400
00:43:59,321 --> 00:44:05,160
So, here is the creation story
as told by science.
401
00:44:08,721 --> 00:44:11,760
In the beginning,
there was an ocean of energy
402
00:44:12,361 --> 00:44:16,560
that drove a rapid expansion
of space known as inflation.
403
00:44:18,561 --> 00:44:20,040
There were ripples in the ocean.
404
00:44:25,041 --> 00:44:29,960
As inflation ended, the ocean of energy
was converted into matter,
405
00:44:31,801 --> 00:44:33,320
then the Big Bang.
406
00:44:40,081 --> 00:44:43,880
And the pattern of the ripples
was imprinted into our universe...
407
00:44:45,401 --> 00:44:48,240
as regions of slightly different density
408
00:44:48,321 --> 00:44:53,440
in the hydrogen and helium gas
that formed shortly after the Big Bang.
409
00:45:14,601 --> 00:45:16,920
The denser regions of gas collapsed...
410
00:45:20,881 --> 00:45:22,840
...to form the first stars...
411
00:45:36,441 --> 00:45:37,920
and the first galaxies.
412
00:45:42,161 --> 00:45:44,200
And nine billion years later,
413
00:45:47,641 --> 00:45:50,840
a new star formed in the Milky Way...
414
00:45:53,081 --> 00:45:54,720
the sun.
415
00:46:02,881 --> 00:46:05,600
The star was joined by eight planets...
416
00:46:07,721 --> 00:46:10,520
including Earth.
417
00:46:16,601 --> 00:46:21,960
And nearly 13.8 billion years
after it all began,
418
00:46:22,721 --> 00:46:24,720
we emerged...
419
00:46:26,641 --> 00:46:29,160
blinking into the light.
420
00:46:59,241 --> 00:47:01,680
"To see the earth as it truly is,
421
00:47:01,761 --> 00:47:06,400
"small and blue and beautiful
in that eternal silence where it floats,
422
00:47:06,481 --> 00:47:09,800
"is to see ourselves
as riders on the earth together,
423
00:47:10,761 --> 00:47:14,440
"brothers on that bright loveliness
in the eternal cold,
424
00:47:15,361 --> 00:47:19,240
"brothers who know now
they are truly brothers."
425
00:47:24,601 --> 00:47:26,520
We all have moments of wonder.
426
00:47:28,001 --> 00:47:29,680
We all dream.
427
00:47:31,281 --> 00:47:35,280
Our thoughts float free,
soaring across the earth
428
00:47:36,161 --> 00:47:38,960
and out into a canopy of stars.
429
00:47:42,881 --> 00:47:47,560
In our most reflective moments,
I think we all understand that
430
00:47:47,641 --> 00:47:51,800
small, though we are,
we are connected to the universe.
431
00:47:53,401 --> 00:47:56,240
We are collections of simple atoms,
432
00:47:57,881 --> 00:48:00,440
but atoms arranged remarkably,
433
00:48:03,601 --> 00:48:08,800
with the urge to explore the universe,
and to comprehend it,
434
00:48:14,361 --> 00:48:19,800
and celebrate our own place
in this great cosmic saga.
435
00:48:25,881 --> 00:48:30,200
And if we follow that saga back,
it takes us on a pilgrimage...
436
00:48:34,201 --> 00:48:36,640
to a time before the dawn,
437
00:48:41,801 --> 00:48:47,440
and to strange ripples that existed
in a universe before our own.
438
00:48:59,761 --> 00:49:02,400
I think we all must wonder
about the meaning of it all.
439
00:49:03,321 --> 00:49:06,040
What does it mean to be human?
Why do we exist?
440
00:49:06,121 --> 00:49:08,000
Why does anything exist at all?
441
00:49:08,881 --> 00:49:11,920
These do not sound
like scientific questions.
442
00:49:12,001 --> 00:49:15,960
They sound like questions
for philosophy or theology, even.
443
00:49:16,601 --> 00:49:18,720
But I think
they are scientific questions
444
00:49:18,801 --> 00:49:23,680
because they're questions about nature,
they're questions about the universe
445
00:49:24,081 --> 00:49:27,560
and the way to understand the universe
is to observe it.
446
00:49:27,641 --> 00:49:31,560
And we've seen ripples in the most
ancient light in the universe,
447
00:49:31,641 --> 00:49:35,160
laid down by events
that happened before the Big Bang.
448
00:49:35,241 --> 00:49:40,720
We've seen billions of galaxies written
across the sky in a giant cosmic web.
449
00:49:40,801 --> 00:49:44,320
And we've seen thousands of planets
orbiting around distant stars,
450
00:49:44,401 --> 00:49:46,840
worlds beyond imagination.
451
00:49:47,441 --> 00:49:49,560
Now, the lesson to me is clear.
452
00:49:49,681 --> 00:49:54,640
We won't answer the deepest questions by
being introverted, by looking inwards.
453
00:49:54,721 --> 00:49:58,560
We will answer them by lifting
our gaze above the horizon
454
00:49:58,641 --> 00:50:02,480
and looking outwards
into the universe beyond the stars.
455
00:50:03,081 --> 00:50:07,600
We used to look to the sky
and see only questions.
456
00:50:07,681 --> 00:50:10,040
Now, we're beginning to see answers.
457
00:50:43,001 --> 00:50:45,240
Hubble is a very special telescope.
458
00:50:45,321 --> 00:50:47,520
It's kind of like
the celebrity telescope
459
00:50:47,601 --> 00:50:49,680
and for a really good reason.
460
00:50:50,361 --> 00:50:54,680
It was the first time that we were
able to launch such a powerful,
461
00:50:54,761 --> 00:50:56,960
large optical telescope into space.
462
00:50:59,681 --> 00:51:03,480
The earth's atmosphere
kind of blurs out lots of our images.
463
00:51:03,561 --> 00:51:05,320
And so, by putting
the telescope in space,
464
00:51:05,401 --> 00:51:09,640
we get these precise,
crystal clear images of our universe.
465
00:51:09,721 --> 00:51:13,600
Three, two, one, and lift-off
466
00:51:13,681 --> 00:51:17,040
of space shuttle Discovery
with the Hubble Space Telescope,
467
00:51:17,121 --> 00:51:19,600
our window on the universe.
468
00:51:19,721 --> 00:51:23,720
The feeling that you get
when the space shuttle takes off,
469
00:51:23,801 --> 00:51:28,040
there's just a sort of...
the sound and the vibrations,
470
00:51:28,121 --> 00:51:30,680
it's just incredibly awe-inspiring.
471
00:51:34,641 --> 00:51:36,440
All rocket boosters
have done their job.
472
00:51:36,721 --> 00:51:38,960
Go ahead, Charlie.
473
00:51:39,721 --> 00:51:41,257
Okay,
we have a go for release,
474
00:51:41,281 --> 00:51:42,920
and we're gonna be a minute late.
475
00:51:59,201 --> 00:52:01,800
We were all sort of
sitting on the edge of our seats,
476
00:52:01,881 --> 00:52:03,840
waiting for the very first images
477
00:52:03,921 --> 00:52:06,960
where Hubble is showing us
what it can see in the universe,
478
00:52:07,881 --> 00:52:12,360
and that turned into
an unexpectedly long wait.
479
00:52:15,161 --> 00:52:16,680
Engineers have discovered
480
00:52:16,761 --> 00:52:19,400
that the giant telescope
has a warped mirror,
481
00:52:19,481 --> 00:52:22,600
which means the images
sent back to NASA are distorted.
482
00:52:24,881 --> 00:52:29,320
We had this very, very
precisely engineered mirror,
483
00:52:29,401 --> 00:52:33,920
but it had been very precisely
engineered to the wrong shape.
484
00:52:37,041 --> 00:52:40,600
For the first three years in the life
of the Hubble, it wasn't producing
485
00:52:40,681 --> 00:52:43,640
the wonderful images
that everyone had expected.
486
00:52:45,881 --> 00:52:48,920
The solution
was the same solution
487
00:52:49,001 --> 00:52:52,080
to the fact that, as a kid,
I couldn't read the blackboard.
488
00:52:52,161 --> 00:52:55,800
The solution was basically
to fit the telescope
489
00:52:55,881 --> 00:52:59,800
with corrective optics,
or something analogous to spectacles.
490
00:52:59,881 --> 00:53:02,320
And we have a go
for main engine start.
491
00:53:02,881 --> 00:53:07,400
Five, four, three, two, one,
492
00:53:08,561 --> 00:53:11,840
and we have lift off,
lift off of the space shuttle Endeavour
493
00:53:11,921 --> 00:53:15,360
on an ambitious mission
to service the Hubble Space Telescope.
494
00:53:15,721 --> 00:53:18,002
It's kind of amazing
that we have to be able
495
00:53:18,041 --> 00:53:22,800
to position this optical equipment to
an accuracy of better than a millimetre,
496
00:53:22,881 --> 00:53:26,760
something that we'd have trouble doing
even on the ground, in your bare hands.
497
00:53:27,481 --> 00:53:30,440
Firm handshake
with Mr Hubble's telescope.
498
00:53:31,161 --> 00:53:33,160
We copy that...
499
00:53:33,241 --> 00:53:37,120
The Vice President and I
wanted to call you and congratulate you
500
00:53:37,201 --> 00:53:39,680
on one of the most spectacular
space missions in our history.
501
00:53:43,481 --> 00:53:48,200
And when Hubble opened
its eyes after they were corrected,
502
00:53:48,281 --> 00:53:52,520
the views that we were able to get
from that telescope changed forever
503
00:53:52,601 --> 00:53:57,440
the way we understood and visualised
the universe that we live in.
504
00:54:02,801 --> 00:54:07,120
The pictures are remarkable.
The trouble with Hubble is over.
505
00:54:12,521 --> 00:54:15,440
It's really hard
to remember what it was like
506
00:54:15,521 --> 00:54:17,480
before we had
the Hubble Space Telescope.
507
00:54:17,961 --> 00:54:20,760
We've gotten so used to these
extraordinary photographs
508
00:54:20,841 --> 00:54:23,840
of the near, of the far,
of the very, very far.
509
00:54:29,001 --> 00:54:30,961
I think, any time I look at
a Hubble image,
510
00:54:31,041 --> 00:54:32,840
my mind gets blown a little bit.
511
00:54:34,561 --> 00:54:38,640
I was the kid that had, like, printouts
of Hubble images in their locker.
512
00:54:43,801 --> 00:54:48,480
Anybody, whether they have the heart
of an astronomer or soul of a poet,
513
00:54:48,561 --> 00:54:51,240
they're going to find things
in the images from Hubble
514
00:54:51,321 --> 00:54:55,200
that just appeal to them
from the point of pure wonder.
515
00:55:06,201 --> 00:55:08,640
Hubble has
not only done the things
516
00:55:08,721 --> 00:55:12,040
that people expected and hoped it would,
517
00:55:12,121 --> 00:55:13,920
but it's actually done a lot of things
518
00:55:14,001 --> 00:55:16,280
that nobody would have
dared to dream of.
519
00:55:19,561 --> 00:55:20,857
One of the biggest discoveries
520
00:55:20,881 --> 00:55:23,360
that came from using
the Hubble Space Telescope
521
00:55:23,441 --> 00:55:25,640
is that, not only is our universe
getting bigger,
522
00:55:25,721 --> 00:55:29,640
it's not just expanding and stretching,
it's actually getting bigger faster.
523
00:55:33,121 --> 00:55:37,560
We can well imagine that the universe
is going to continue to expand
524
00:55:37,641 --> 00:55:41,480
and get so big that, eventually,
the galaxies will just disappear.
525
00:55:41,561 --> 00:55:46,280
They'll be so far away from us and
moving so rapidly that we have no hope
526
00:55:46,361 --> 00:55:49,840
of seeing any light from them,
and that's a real possibility
527
00:55:49,921 --> 00:55:51,920
for what could happen in the future.
528
00:55:55,241 --> 00:55:56,777
We still have these mysteries of
529
00:55:56,801 --> 00:56:01,400
what's really driving
this new phase of accelerated expansion,
530
00:56:01,481 --> 00:56:04,320
and we're building new tools
to try to refine those questions.
531
00:56:19,641 --> 00:56:23,000
The Hubble telescope
which was a marvel for its time
532
00:56:23,081 --> 00:56:26,200
is really far behind
what we would design today.
533
00:56:30,361 --> 00:56:34,400
It will be completely outclassed
by the next generation telescope,
534
00:56:34,481 --> 00:56:38,760
the James Webb Space Telescope,
which will see even deeper than Hubble.
535
00:56:43,001 --> 00:56:47,240
And that will give us
unprecedented detailed views.
536
00:56:47,321 --> 00:56:51,240
We can use it to see through
some of the very dense,
537
00:56:51,321 --> 00:56:55,600
murky dust clouds and actually see
stars in the process of forming.
538
00:56:56,881 --> 00:57:01,280
We also can use it to look further
and further back in time.
539
00:57:03,641 --> 00:57:07,160
That's going to be a very, very exciting
story which is going to unfold,
540
00:57:07,241 --> 00:57:09,560
I think, within
the next three or four years.
541
00:57:21,161 --> 00:57:24,480
Hubble is still king
because it's still a big observatory
542
00:57:24,561 --> 00:57:27,560
in comparison
to what we've had in space before.
543
00:57:28,841 --> 00:57:31,800
Hubble is a unique instrument
for making discoveries that
544
00:57:31,881 --> 00:57:34,200
no other telescope
could possibly have made.
545
00:57:39,441 --> 00:57:42,040
I think, when you think
about an image of space,
546
00:57:42,121 --> 00:57:44,360
when you think about space,
you think of a Hubble image.
547
00:57:44,384 --> 00:57:47,384
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