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NASA's Parker Solar Probe.

A daring mission to shed light on the
mysteries of our closest star.

This is a journey into Never Never Land,
you might say.

NASA's Parker Solar Probe is the first
spacecraft to touch a star.

It's designed to fly through the sun's
atmosphere.

Braving temperatures no spacecraft has
ever endured.

The Parker Solar
Probe is allowing us to

know our star as we've
never known it before.

And it's also helping us to tell the story
of all the stars.

Our sun is from a long line of stars
dating back to the dawn of time.

From fierce blue giants, which first lit
up the universe.

To later generations, whose deaths enrich
the cosmos with precious elements.

The building blocks of our solar system.

And

allowed our sun to create the thing which
brings meaning to the cosmos.

Life.

You and me.

We have a strange relationship with the
stars.

Somewhere between awe and indifference.

I think we take our star, the sun,
for granted.

Partly because of its predictability.

Every day it rises in the east and sets in
the west.

Without any help or reverence from us.

But many ancient cultures deified the sun.

They treated it as a god.

And the sun gods were creators and
destroyers of worlds.

So, which is it?

Well, I think that the modern story of the
stars, as told by science, which is

indisputably an epic story, stretching
back over 13 billion years to the origin

of the universe, places them firmly in the
realm of the gods.

If we want to understand where these gods
came from, we have to go back

to a time before the stars.

In the beginning, the universe was dark.

But it was not empty.

Something was lurking in the void.

Stretching out tendrils.

The cosmic web grew to become a vast
structure.

Criss-crossing the entire universe.

It

was formed by interlocking filaments of
dark matter.

And it was at the places where these
filaments met, the intersections,

that the first stars, our sun's earliest
ancestors, were born.

The cosmic web is the scaffolding of the
universe.

The vast and intricate structure.

That spans the void.

The web is made primarily out of dark
matter.

A mysterious substance that dominates the
universe.

Although we don't know what it is.

It's one of the great mysteries in modern
physics.

It's probably some
kind of particle that

interacts very weakly
with itself and with light.

If it doesn't interact with light,
you can't see it.

That's why it's called dark matter.

But it does influence the universe through
its gravity.

It was in the dark heart
of the cosmic web that

gravity began to sculpt
the early universe.

Drawing together the two simplest
elements, hydrogen and helium.

The raw material for the very first stars.

Hydrogen gas clings to the filaments of
the web.

Attracted there by the gravitational pull
of the dark matter.

And where those filaments cross,
the gas can become dense enough to

collapse under its own
gravity to form great clusters

of galaxies, each filled
with billions of stars.

The universe was approaching a turning
point.

Hydrogen and helium poured into the
regions where the filaments crossed.

Gathering into ever denser clouds.

Gravity asserted its grip.

And the clouds of gas began to collapse.

Becoming denser and denser.

And in the densest regions, the gas became
so hot that nuclear fusion reactions began.

And out of the maelstrom, the first gods
emerged.

And there was light.

The stars illuminate the universe.

But that is the least interesting thing
that they do.

The thing that makes
the universe interesting,

that brings meaning
to the universe, is that.

Life.

You.

And me.

And life is just chemistry.

And chemistry requires complex chemical
elements.

The only thing that existed in the universe
before the stars was hydrogen and helium.

Life requires carbon and oxygen and iron.

All those things were made in a process
called nuclear fusion.

In the cores of stars,
or even for the heavier

elements like gold, in
the collisions of stars.

So, without the stars, the universe would
be uninteresting.

It would be meaningless.

It would be just an infinite box of gas.

The first stars were monsters.

Hundreds of times as massive as our sun.

They burnt with such ferocity,
that they shone blue.

With surface temperatures in excess of
100,000 degrees.

They were the largest stars ever to have
lived.

Violent and volatile giants.

A star is essentially a balancing act.

The force of gravity.

Gravity is constantly trying to collapse
it.

And that pushes its ingredients,
primarily hydrogen, single protons,

closer and closer together.

Now, when those protons get close enough
together, another of the fundamental

forces of nature, the strong nuclear
force, takes over.

And it can stick the protons together.

That releases energy, which creates a
pressure, which holds the star up.

Now, the more massive the star,
the stronger the inward pull of gravity,

and the more energy has to be released to
maintain the balance.

And so, the faster the ingredients are
used up.

These giant stars were in a struggle for
survival.

Fighting the relentless pull of gravity.

Consuming more and more hydrogen fuel to
maintain their precarious equilibrium.

For most of its life, the star burns
hydrogen, the simplest chemical element,

with one proton in its nucleus,
into helium, with two protons.

Now, when it runs
out of hydrogen in the

core, the core starts
to collapse and heat up.

And the star responds by building ever
more complex elements.

So, it makes carbon with
six protons and oxygen with

eight protons, releasing more
and more energy as it goes.

But when the star has assembled iron in
its core, with 26 protons in its nucleus,

no more energy can be released.

The star loses its battle against gravity.

It collapses.

And in a final moment of creation,
of salvage, if you like, from its

destruction, it distributes
those newly minted

heavy chemical elements
out into the universe.

Imagine we could journey back in time and
watch the first star live out its brief,

luminous life.

After only a million years, the star used
up all of its fuel.

The core collapsed.

The star imploded.

And

then rebounded in a colossal explosion.

A supernova.

In death, the first stars began to
transform the cosmos.

Enriching the ocean
of hydrogen and helium,

which filled the universe
with heavy elements.

To build new generations of more complex
stars.

Over time, these elements gathered
together,

creating rich clouds of gas and dust.

Nurseries, where new generations of stars
were born.

And not just stars, but families of stars.

The first galaxies.

And around this time, some of the earliest
star systems formed in our own galaxy.

The Milky Way.

A new age of complexity was dawning in the
universe.

Now, there were stars of different sizes.

And different colours.

And crucially, new bodies had appeared.

Planets.

Places where the rich
chemical elements, built by

previous generations of
stars, could finally find a home.

Countless billions of
stars have come and gone

since those first giants
illuminated the darkness.

Each enriching the
universe with the material

out of which the next
generation formed.

Blue stars and white stars, single stars,
double stars, even triple star systems

orbiting around each other.

The conditions were now
right for those stars to drive

the universe into a new and
profound age of complexity.

Our sun was formed from the ashes of
generations of ancestors.

Just one small star in a galaxy of
billions of brilliant gods.

For the first million years of its life,
the sun was virtually alone.

Wreathed in clouds of gas and dust.

The dust slowly clumped together,

forming clusters the size of pebbles.

Then, boulders.

And finally, planets.

But the planets were lifeless rocks.

Only the sun had the power to turn them
into worlds.

Some were too far away from the sun.

Ice giants.

Frozen, seemingly, into infertility.

Others fought for their lives.

Some formed too close to the sun.

Seared by a relentless light.

They became scorched desert worlds.

But there was a planet in the sun's
family.

That quite by chance formed neither too
close nor too far away.

An Arcadia.

Where our star could breathe life into
dust.

The planets are just the leftovers from
the formation of stars.

Some sort of debris, if you like.

It's just little specks orbiting around
those magnificent flames.

But the planets are also the places in the
universe where gravity has concentrated

the heavy elements built by previous
planets.

The biggest generations of stars.

And that makes the planets the canvas on
which the stars can create.

The canvas on which the stars can create.

What do I mean by that?

Well, just look around.

Everywhere you look on Earth there is
complexity.

Not only mountains and rivers,
but living things, animals and plants,

human beings, human civilization.

The most complex thing we know of anywhere
in the universe.

So, you have to ask yourself,
how can it be that such

complexity can emerge
completely naturally in the universe?

Well, the answer, in fact, was known in
the 19th century.

And it comes from the science of
thermodynamics.

In the 19th century, people were interested
in the efficiency of steam engines.

Steam engines are, after all, the machines
that powered the factories that allowed

people to build increasingly complex
things.

And it turns out that the only thing that
matters for a steam engine, the thing that

determines its efficiency, the thing that
allows it to do work and build things,

is the temperature difference between the
fire, the furnace, at the heart of the

steam engine, and the cold environment
surrounding it.

In the universe, the stars are hot spots
in a cold sky.

We are sitting, in a very
real sense, inside a giant

steam engine powered
by the furnace of the sun.

And it's in that sense that the stars are
the creators of complexity in the universe.

But creating complexity is a subtle art.

You need an engine, in this case a star,
that's not too wild and flashy.

A star which is consistent enough,
for long enough, to kindle the sparks of

life, and allow those sparks to flicker
and flourish.

The most important prophecy of a star,
if it's to nurture a civilisation,

is magnificent dependability.

No one knows exactly how life on Earth
emerged.

But what we do know, is that at some
point, primitive cells, living in the

ocean, began using the sun's energy to
power life-giving chemical reactions.

These cells formed a bridge between Earth
and sun.

Delicate engines, which
harness the fires of our star,

using sunlight to turn carbon
dioxide and water into food.

This process, known as photosynthesis,
unleashed the sun's creative power.

And

drove the evolution of complexity.

From primitive bacteria, to plants,
and trees, and,

ultimately, to you and me.

You know, photosynthesis is a process
that's very easy to describe in words.

The plants take energy from the sun,
and use it to react carbon dioxide and

water together, to make sugars,
and a waste product, oxygen.

Really easy to say, very difficult to do.

I mean, there's a part of that
photosynthetic machinery, everything you

see here, every plant on the planet,
called Photosystem II.

It's comprised of 46,630 atoms, all
working together in an intricate machine.

Very, very complex.

Efficient.

It took billions of years of evolution.

Then we eat the plants, or we eat
something that's eaten the plants,

and we do the reverse reaction.

We take those sugars, and we breathe in
that waste product, oxygen, react them

together, release a bit of energy,
a bit of the stored sunlight, if you like,

and we use that energy to maintain our
structure, to grow, to live.

Trillions of stars have existed since the
universe began.

But ours has nurtured that most miraculous
thing.

Life.

And that makes the Sun a truly remarkable
star.

That is the only star we know of anywhere
where there are collections of atoms in

orbit around it, you and me, that have
named it the Sun.

Our Sun.

We've worshipped it, deified it,
since the dawn of history.

In fact, it's been argued that the Sun
lies at the foundation of all religion.

And there may be some truth in that.

In fact, I think there is a deep truth in
that, because we all owe our existence,

this brief time we have in the universe,
to that star.

In fact, in a deeper sense, to all the
stars.

We don't need to invent, imaginary gods to
explain the universe.

We can replace them with the real thing.

Everyone we love.

Everything we value.

Our supreme accomplishments as a
civilisation

were created and crafted by stars.

There are over 200 billion stars in our
galaxy.

And there are two trillion galaxies in the
observable universe.

We're living in the age of stars.

An era of light and life in the cosmos.

From our fleeting human perspective,
stars seem eternal.

But even gods are not immortal.

Where there is light, there is darkness.

Stars are creators.

But they can be jealous guardians of their
creations.

Many smaller stars don't die in
spectacular explosions.

Instead, they slowly fade away.

They hang on to the precious elements they
made.

Becoming fossil stars.

And as more fossils
litter the universe,

more life-giving elements
remain locked away.

Starving the cosmos of the material needed
to make new generations of stars.

The age of stars may seem infinite.

But it had a beginning.

And it will also have an end.

Imagine a timeline of the universe.

And imagine that this is the origin of the
universe.

A big bang 13.8 billion years ago.

After 100 million years or so the first
stars formed.

On this scale one centimeter is about 20
million years.

After 4 billion years the peak rate of
star formation occurred.

The maximum number of new stars were born.

After 9 billion years our sun was born.

And today we stand 13.8 billion years ago.

About half way through the lifetime of our
sun.

Now in about 5 billion years time our sun
will die.

But new stars will be born.

And many of the older stars in the universe
the smaller stars will continue to shine.

In fact we think that the last star will
cease to shine.

The universe will go dark in around 10
trillion years.

On this scale that's about 5000 meters
away from the big bang.

But that's not the end of the universe.

As far as we know the universe will
continue expanding forever.

And so the age of starlight
is the briefest moment

of time in the infinite
history of the universe.

The age of darkness will go on and on and
on.

Stars won't just disappear of course.

They'll be here for eons to come.

But over time the universe will grow
darker colder and emptier.

There are stars around today that existed
close to the beginning of the age of stars.

And some of them are still here today.

also witness the end.

They're the longest lived stars in the
universe.

Red dwarfs.

Trappist-1 is one of these ancients.

It's already more than 7 billion years
old.

Almost twice as old as our sun.

But only around a tenth of the size.

And less than one percent as bright.

It's a cool star.

Slow burning.

And that is the secret of its longevity.

Because they burn slowly red
dwarfs live for a very long time.

Like the sun, Trappist-1 has its own
planets.

Seven rocky worlds.

Each roughly the size of Earth.

Some may have atmospheres.

And even oceans.

But there the similarity ends.

Because these are strange worlds.

Every one of these planets is locked in
its orbit.

One side facing Trappist-1.

The other side frozen.

Permanently exposed to the cold void of
space.

If you could stand on the surface of one
of these ancient worlds.

As the eons passed,

you could watch the future of the cosmos
slowly unfold.

And one day, five billion years from now,

you will

The death of our sun will probably go
unremarked.

I doubt that we'll be around to see it.

Maybe some alien astronomer
on a world far away across the

Milky Way will see it through
the end of their telescope.

But I don't think they'll give it a second
thought.

We've seen hundreds of stars die,
and we don't give them a second thought.

But I think the death of
our sun will matter here,

locally, in this little
corner of the galaxy.

Because it will mark the end of a glorious
time in the history of our galaxy,

where meaning, where
science and literature

and art and poetry
and music existed here.

And that does matter.

Why does meaning have to be eternal?

It's the fragility of our lives that makes
them valuable.

I think the wonderful thing is that our
star has taken the laws of nature here on

this planet and crafted such a magnificent
expression of them.

You and me and all this.

Stars like TRAPPIST-1 will linger on long
after the death of our sun.

We

will never know the name of the last star.

But we know

that it It will be a red dwarf.

The last star will slowly cool and fade
away.

With its passing the universe will become
once again a void.

Without light or life or meaning.

The stars will illuminate the universe and
create its most intricate structures.

And one day they will all be gone.

I mean the stars are gods but they're
mortal gods.

And when that time comes and the last
stars have faded and all possibility of

life and meaning in the universe has faded
with them they will have left the most

profound legacy.

Because for a moment in the
long history of the universe the

stars illuminated the dark and
allowed us to illuminate it too.

We want to study the sun because it
teaches us a lot about stars.

It teaches us a lot about
all the other millions

and billions of stars in
our galaxy and beyond.

There was a moment when we were putting
the spacecraft together that I just took a

moment and looked at the spacecraft and
realized this is going into a star and to

realize how special it was to be able to
have worked on this and that humanity

decided this was something we wanted to
do.

Minus 30.

Status check.

Go Delta.

Go PSP.

Minus 15.

Launch night.

I was sick to my stomach.

Five, four, three, two, one, zero.

Liftoff of the mighty Delta IV heavy
rocket with NASA's Parker Solar Probe.

There we go.

The spacecraft is the first that NASA has
named after a living person because Eugene

Parker is really such, you know,
an eminent physicist in our field.

The Delta IV heavy is a very slow rocket
compared to the other launches I've seen.

So I just saw fireballs and was very,
very frightened for a while.

Twenty-five seconds into flight.

Chamber pressures continue to look good on
all three boosters.

Then realizing that this was all okay as
it slowly made its way up into the sky.

Now 50 seconds into flight.

Parker Solar Probe is so
revolutionary because it's the

first time that we're actually
going in to touch the sun.

We're going 94 percent of the
way from the Earth to the sun

to actually experience the solar
corona, the sun's atmosphere.

I think that closest approach,
it'll be about eight solar

radii from the sun, which
is just mind-blowingly close.

So we were expecting things
to be very hot, over 2,500

Fahrenheit, but in a soup
of a million degree plasma.

That's a real challenge for the spacecraft
to survive that environment.

So in order to do that, there's a very
large heat shield on the front of the

spacecraft, which
protects the majority of the

instruments which are sat
behind on the spacecraft body.

What makes Parker so great is the fact
that it has a set of instruments that work

together in order to look
in all directions in order

to solve those big mysteries
about the solar wind.

The solar corona has been mysterious to us
since we've known about it.

So it's a very strange thing.

The surface of the sun is sort of 6,000
degrees.

And then above that, you have this very
thin atmosphere that's a million degrees,

super hot.

And the way that's heated, we know it has
something to do with magnetic fields,

but we don't know exactly how it works.

That's where the solar wind is generated.

We don't know quite exactly how that works
either.

Other things that have come out of this
are coronal mass ejections.

When we originally did the proposal,
we were thinking that we would see five in

the entire seven-year mission if we were
lucky.

We ended up seeing around four to five in
the first year.

So there has been just a total
switch in terms of how active

the sun is or what we classify
as coronal mass ejections.

Maybe a little bit of both.

It is a joy to see all the data coming
back.

It's a joy to share it with
others and to see them

be as curious as I have
been for the last decade.

So Parker's just begun its mission,
really, and it's already really started to

truly transform our understanding for how
the sun works.