All language subtitles for 764E92A7F8E33864F8A743F6C8699DA3_eng

We pulled the stars from the skies...

and brought them down to Earth.

But at what cost?

When we turned on all these lights...

we lost something precious.

The stars.

A long time ago,
in a world lit only by fire...

our relationship with the stars
was far more...

personal.

For thousands of generations...

we watched the stars
as if our lives depended on it.

Because they did.

We humans were not the biggest,
the strongest...

nor the fastest of all the animals
we competed against.

But we did have one thing going for us:
our intelligence.

One aspect of that was a genius
for pattern recognition.

Night after night, we watched the stars.

And over time, our ancestors noticed
that the motions of the stars...

across the nights of the year
foretold changes on Earth...

that threatened or enhanced
our chances for survival.

In a time when our imaginations were the
only stage where stories came to life...

before there were movies or TVs
or electronic devices of any kind...

every human culture connected the dots
to form their own pictures.

These images became the illustrations
of a storybook...

that, on a deeper level,
was also a survival manual.

The names and personalities of the gods,
heroes, farm animals or familiar objects...

varied from culture to culture.

But there was one particularly gorgeous
group of stars...

known to the ancient Greeks
and to us today as the Pleiades...

a star cluster formed
about a hundred million years ago.

Each of them is some 40 times brighter
than our sun.

And Alcyone, the most luminous,
outshines our sun a thousand times.

For ages, the Pleiades
have been used as an eye test...

for people all over the world.

If you could see at least six of them,
you were considered normal.

If you saw more than seven...

you were an ideal candidate
for a warrior or scout.

Among the ancient Celts and Druids
of the British Isles...

the Pleiades were believed
to have a haunting significance.

On the night of the year that they reach
the highest point in the sky at midnight...

the spirits of the dead
were thought to wander the earth.

This is believed to be the origin
of the holiday once known as Samhain...

now called Halloween.

All over the earth,
our ancestors told wonderful stories...

to explain how the Pleiades came
to be in the sky.

For the Kiowa people of North America,
it happened something like this.

Long, long ago, some young women
snuck away from their campsite...

to dance freely beneath the stars.

Rock, save us.

Rock, take pity on us.

The rock heard their cries and grew taller.

Until it became what is today known
as the Devils Tower.

The maidens were transformed
into the stars of the Pleiades...

which may be seen hanging
above the tower in midwinter.

The ancient Greeks also saw
those seven jewels as seven maidens...

the seven daughters of Atlas...

pursued not by bears,
but by Orion the hunter...

who spied them
when he was out walking one day.

Orion became mad with desire.

For seven years, he
chased them relentlessly.

Exhausted...
Zeus, help us.

They prayed to Zeus for deliverance.

Zeus, the king of the gods,
felt sorry for them...

and transformed those seven maidens
into the Pleiades.

But the gods are, if anything, capricious.

When Orion was killed
by the sting of a scorpion...

Zeus placed him in the sky...

where he could resume his pursuit
of the seven gorgeous sisters.

Our ancestors,
they wove brilliantly imaginative stories.

But they can bring us no closer
to the stars than our dreams.

It took yet another few thousand years...

until three brilliant scientists
unlocked the secrets...

of the true lives of the stars.

In 1901, Harvard was a man's world.

But an astronomer
named Edward Charles Pickering...

broke that rule.

Old Pickering's office
is just down the hallway.

And that door over there leads to the room
where he keeps his computers.

We're supposed
to call those women "computers"...

but, uh, I've heard more than one fellow
refer to those gals...

as "Pickering's Harem."
Ha-ha-ha.

Pickering assembled a team of women
to map and classify the types of stars.

One of them provided the key
to our understanding...

of the substance of the stars.

And another devised a way for us
to calculate the size of the universe.

For some reason, you've probably
never heard of either of them.

Wonder why.

That's Annie Jump Cannon,
the leader of the team.

Before she was through,
she cataloged a quarter of a million stars.

Number 11 is a B7.

That's Alcyone in the Pleiades.

Cannon lost her hearing
during a bout of scarlet fever...

when she was a young woman.

Number 12 is a B6.

That's Henrietta Swan Leavitt.

She's also deaf.

And she's the other great scientist
in the room.

Leavitt discovered the law that astronomers
still use more than a century later...

to measure the distances to the stars
and the size of the cosmos itself.

Annie Jump Cannon
sent out a Christmas card explaining...

what she and her sisters
were actually doing.

The light from a star is allowed...

to fall through a prism placed
in the telescope, she wrote.

Thus magnified, the starlight is split up
into a band showing its component colors...

the red rays going to one end
and the violet to the other.

This is the spectrum of the star.

It shows the presence of fine, dark lines.

By comparing them with lines given
by glowing substances in the laboratory...

we can determine that the same elements
familiar to us on the Earth...

also exist in the outermost star.

This is plate number 123588.

Number one at this plate
is a B-type star.

Make that a B2.

It took Cannon decades
to classify the spectral character...

of hundreds of thousands of stars...

according to the scheme that she devised.

Cannon discovered that the stars fell
into a continuous sequence...

of seven broad categories according
to their spectral line patterns.

Each was designated by a letter.

But the spectral lines of two stars
in the same letter class...

could differ in subtle ways...

minute variations that Cannon learned
to recognize from memory.

To distinguish these spectra
from one another...

she assigned ten numerical subcategories
for each class.

Annie Jump Cannon organized the stars...

but it would fall to another scientist
to decipher the hidden meaning in her work.

In the England of 1923,
women were forbidden

from pursuing advanced
degrees in science.

But Cecilia Payne
had attended a lecture in London...

b y the astronomer Sir Arthur Eddington...

the first scientist to provide evidence...

that Einstein's revolutionary
General Theory of Relativity was correct.

From that moment on,
she knew that nothing

would deter her from
pursuing her big dreams.

She resolved to emigrate to America...

where women had already gained the freedom
to study the stars.

Her application was accepted at Harvard.

What she would discover there...

would challenge one of the central beliefs
of astronomy.

The resulting impact would be the dawn
of modern astrophysics.

As the decades passed...

Annie Jump Cannon and her team
kept sifting the stars...

checking each one's spectral signature
with a fleeting glance...

and then dropping them
into one of seven categories.

They became hundreds of thousands of dots
in a larger picture...

which no one could yet understand.

Into this community of women
came one more.

Well, hello there.

You must be Miss Payne.

We've been waiting for you.

Come on in.

Cecilia Payne
had never experienced such kindness...

in a scientific setting before.

This sisterhood generously shared
the fruits of their labors with her...

and she turned their observations into
a radical new understanding of the stars.

The two women became great friends.

Cannon taught Payne everything
she had learned about stellar spectra.

And Payne began
to analyze Cannon's data...

to see if she could determine
the actual chemical composition...

and physical state of the stars.

She brought to this work her expertise
in theoretical and atomic physics.

The most prominent features
in the spectra of stars...

showed the presence of heavy elements
such as calcium...

and iron, which are among
the most abundant elements in the Earth.

So astronomers naturally concluded
that the stars...

were made of the same elements as the Earth
and in roughly the same proportions.

In 1924, Henry Norris Russell
was the dean of American astronomers...

having made major contributions
to our understanding of the stars.

Forty to 45 of the chemical
elements that we have here on Earth...

are also present
in the spectrum of the sun.

So we can assume that the composition
of the sun resembles that of the Earth.

If one were to heat the crust of the Earth
to incandescence...

its spectrum would resemble that
of the sun.

Annie, I think I now understand
what it all means.

All your years of work.

Tell me.

I've calculated what the spectra
should look like...

across a wide range
of temperatures...

and they match your system
of classification perfectly.

The spectrum of any star
tells you exactly how hot it is.

Your "O-B-A-F-G-K-M" is really
a temperature scale of the stars...

from the hottest to the coldest.

Here's the headline, Annie.

Thanks to your work,
I've discovered that the stars...

are made almost entirely
of hydrogen and helium.

There's a million times more hydrogen
and helium than the metals in the stars.

I know, it sounds daft.

Are you certain?

Has anyone else checked
your calculations?

Not yet, but it's all in my thesis...

which is already on its way
to Professor Russell.

Poor woman.

Russell felt sorry for Cecilia Payne.

Her thesis appeared to him
to be fundamentally flawed.

It is clearly impossible that hydrogen...

should be a million times more abundant
than the metals.

Her carefully gathered evidence flew in
the face of conventional scientific wisdom.

"How could I be right," she asked...

"if that must mean that
such a distinguished scientist was wrong?"

Despite her confidence
in the quality of her research...

she caved and added
a sentence to her

thesis that undermined
its greatest insight.

It would be four years before
Russell realized that Payne was right.

To his credit, as soon as he did,
he acknowledged that it was her discovery.

Payne's "Stellar Atmospheres"
is widely regarded...

as the most brilliant PhD thesis
ever written in astronomy.

It became the standard text in its field.

I was to blame
for not having pressed my point.

I had given in to authority
when [believed I was right.

If you are sure of your facts,
you should defend your position.

The words of the powerful may prevail
in other spheres of human experience...

but in science,
the only thing that counts...

is the evidence
and the logic of the argument itself.

Cecilia Payne's interpretation...

of Annie Jump Cannon's sequence
of stellar spectra...

made it possible for us
to read the life stories of the stars...

and to trace the story of life itself back
to its beginnings in their fiery deaths.

There are many kinds of stars.

Some are bright like the sun.

Some are dim.

The greatest stars are ten million
times larger than the smallest ones.

Some stars are old beyond imagining,
more than ten billion years of age.

Others are being born right now.

When atoms fuse in the hearts of stars,
they make starlight.

Stars are born in litters...

formed from the gas and dust
of interstellar clouds.

The mass of the individual stars
in a litter can range from the runts...

Not much larger than the largest planets.

To the supergiant stars that dwarf the sun.

The stars in the nebula below Orion's Belt
are newborns...

around five million years old...

and still swaddled in the gas and dust
that gave birth to them.

The stars in the Pleiades are already
toddlers, about 100 million years old.

They've shed their blankets
of gas and dust...

but they're still bound together
by their mutual gravity.

Another few hundred million years...

and they'll drift apart
and go their separate ways...

never to meet again.

Most of the stars of the Big Dipper
are adolescents...

roughly a half a billion years old.

They've already drifted apart
from their birth cluster...

although we can still trace
their common ancestry.

Eventually, they'll spread out
around the Milky Way galaxy.

But most of the familiar constellations
are a mix of entirely unrelated stars...

some faint and nearby,
others bright and far away.

Our own sun?

From the distance of even a few
light-years...

it's hard to find amidst
the other stars.

It's that one.

Our sun is middle-aged and
a long way from where it was born.

It's sister stars, hatched from
the same interstellar cloud...

are dispersed throughout
the galaxy.

Many of them have
their own planets.

Perhaps some of them nurture
the evolution of life and intelligence.

Most of the stars in
our night sky actually

orbit around one or
more stellar companions.

With the naked eye, we usually
can't see the fainter members...

in such double
and multiple star systems.

On a world with three suns,
the nights would be rare...

and the days might alternate
between red and blue.

It is the destiny of stars to collapse.

Of the thousands of stars you see
when you look up at the night sky...

every one of them is living in an interval
between two collapses:

An initial collapse of a dark,
interstellar gas cloud to form the star...

and a final collapse of the luminous star
on its way to its ultimate fate.

Gravity makes stars contract,
unless some other force intervenes.

The sun is a great big ball
of incandescent gas.

The super-hot gas in its core pushes
the sun to expand outward.

At the same time, the sun's own gravity
pulls it inward to contract.

And our sun is poised between
these two forces in a stable equilibrium...

between gravity and nuclear fire.

A balance it will maintain
for another 4 billion years.

But as the sun consumes hydrogen,
its core very slowly shrinks...

and the sun's surface gradually expands
in response.

It happens very slowly, imperceptibly,
over the course of millions of years.

But in about a billion years, the sun will
be 10 percent brighter than it is today.

Ten percent may not
sound like much, but that

extra heat will have
a big effect on Earth.

When the sun finally exhausts its nuclear
fuel 4 or 5 billion years from now...

its gas will cool and
the pressure will fall.

The sun's interior can no longer support
the weight of the outer layers...

and the initial collapse will resume.

Nothing lasts forever.

Even the stars die.

Helium, the ash of 10 billion years of
hydrogen fusion, has built up in the core.

With no nuclear fire to sustain its weight,
the core collapses...

until it becomes hot enough to start
fusing helium into carbon and oxygen.

The core of the sun is now much hotter
than it was before.

It's atmosphere rapidly expands.

Over the next billion years,
it'll become bloated...

to more than 100 times
its original size, a red giant star.

It will envelop and devour
the planets Mercury...

and Venus...

and possibly the Earth.

I like to think that tens of millions of
years before that far distant future...

if there still be life born of Earth, it
will have found new homes among the stars.

Once the sun burns through its helium,
it will become highly unstable...

casting off its outer layers into space.

The exposed, super-hot core...

will flood its surroundings
with high-energy ultraviolet light.

The atoms will perform a wild,
fluorescent dance.

The sun will collapse
like a souffle, shrinking

a hundredfold to
the size of the Earth.

And at that point, the
sun will be so dense...

that its overcrowded electrons will push
back, stopping any further contraction.

The kernel of light at the center will be
the only part of the sun that endures...

a white dwarf star that will go on shining
dimly for another 100 billion years.

Will the beings of a distant future,
sailing past this wreck of a star...

have any idea of the life and worlds
that it once warmed?

The psychedelic death shrouds
of ordinary stars are fleeting...

lasting only tens of thousands
of years...

before dissipating in
the interstellar gas and

dust from which the
new stars will be born.

The stars in a binary star system
can have a different fate.

Sirius, the brightest star in the night
sky, has a very faint stellar companion...

a white dwarf.

It was once a sun-like star.

Someday, when Sirius runs out of fuel
and becomes a red giant...

it will shed its substance
onto the white dwarf.

The intense gravity of
the companion will attract

that gas, pulling it
into a spiraling disk.

When the gas from the larger star falls
onto the surface of the white dwarf...

it will trigger nuclear explosions.

The greatest burst will release
100,000 times more energy than the sun.

Each one of those star bursts
is called a "nova"

from the Latin for "new."

A star about 15 times as
massive as the sun, one like Rigel...

the blue supergiant
that forms the right

foot of Orion, has a
different fate in store.

It's collapse will not be stopped
by the pressure of electrons.

The star will keep falling in on itself...

until its nuclei become so overcrowded
that they push back.

Rigel will shrink down
about 100,000 times...

until there's no space left between
the nuclei and it can shrink no more.

At that point, it ignites a more powerful
nuclear reaction: A supernova.

Most stellar evolution takes millions
or billions of years.

But the interior collapse that triggers
a supernova explosion takes only seconds.

What remains will be an atomic nucleus
the size of a small city...

a rapidly rotating
neutron star called a pulsar.

But for a star more than 30 times
as massive as the sun...

a star like Alnilam in Orion's Belt,
there will be no stopping its collapse.

In a few million years, when Alnilam runs
out of fuel, it, too, will go supernova.

The imploding core of Alnilam
will be so massive...

that not even nuclear forces will be
strong enough to hold off its collapse.

Nothing can withstand such gravity.

And such a star has an astonishing destiny.

It will continue to collapse,
crossing a boundary in space-time...

called the "event horizon,"
beyond which we cannot see.

When it traverses that frontier,
the star will vanish completely from sight.

It will be inside a black hole,
a place where gravity is so strong...

that nothing, not even light, can escape.

But there's an even more dramatic fate
that awaits a rare kind of star.

There's one of them in our galaxy.

It's so unstable that when it goes,
it won't become a mere nova or supernova.

It'll become something far more
A hypernova.

And it could happen in our lifetime.

There are few places on Earth
to get a better view of the night sky...

than the Australian Outback.

No buildings, no cars, streetlights,
nothing out here, just lots of starlight.

And the occasional kangaroo.

You can get a particularly good view
of the Milky Way from down here.

The center of our galaxy rises high in the
sky, and it arches across the heavens...

like the backbone of night.

We live in a spiral galaxy.

And when we look at the Milky Way...

we re seeing light from billions of stars
in its spiral disk.

And under this beautiful
dark sky, you can see

that the Milky Way isn't
a uniform band of light.

There are dark patches,
breaks in the starlight.

Those dark patches
are caused by interstellar dust.

The dust blocks the starlight,
and there's lots of it.

Most cultures looked up at the stars
and connected the dots...

to form familiar images in the sky.

Constellations.

But the Aboriginal people of Australia
saw a pattern in the darkness...

running through the Milky Way.

They saw an emu,
a large bird native to this continent.

Not in the stars,
but in the absence of stars.

There are so many ways
to look at the night sky.

For a million years or more,
we've watched the sky.

And a lot's happened in that time.

Supernova explode in our galaxy
about once a century.

If we could compress all those nights
of stargazing into a single minute...

this is what we would see.

Now, if our eyes were telescopes...

if they were light buckets
as big as wagon wheels...

and our vision was not limited
to just one kind of light...

then this is the Milky Way
we would see.

A galaxy in near-infrared light
with streaming tendrils of dust...

hurled outward by those
exploding supernovas...

"silhouetted against a backdrop
of countless stars."

About 7500 light-years away,
in another part of our galaxy...

there is a place of upheaval
on an inconceivable scale.

This is the Carina Nebula.

A star-making machine.

It takes a ray of light
50 years to cross it.

The titanic stars born here
sear the surrounding gas and dust...

with their fierce ultra violet radiation.

When a massive star dies,
it blows itself to smithereens.

It's substance is propelled
across the vastness...

to be stirred by starlight
and gathered up by gravity.

Stars to dust and dust to stars.

In the cosmos, nothing is wasted.

But there's an upper limit
to how massive a star can be.

Back in the 17th century,
when Edmond Halley crossed the equator...

to map the southern constellations...

Eta Carinae seemed like
just another faint star.

But in 1843, Eta Carinae suddenly became
the second brightest star in the sky...

outshined only by Sirius.

And it's been flipping out ever since.

That dumbbell-shaped cloud
is the expanding remnant of that event.

At its center is one crazy star.

Talk about unstable,
Eta Carinae is at

least 100 times more
massive than the sun...

and pouring out 5 million times more light.

It's pushing the upper limit
of what a star can be.

What's more, there's
evidence that Eta

Carinae is being
gravitationally tormented...

by an evil twin...

another massive star in orbit around it
as close as Saturn is to the sun.

The core of a supermassive star
pours out so much light...

that the outward pressure can overwhelm
the star's gravity.

If a star is too massive, its radiation
pressure overpowers its gravity...

and blows the star apart.

The fate of Eta Carinae was sealed
when it was born millions of years ago.

When it finally does blow up...
And who knows, maybe it already has...

after all we're looking at it by light
that left the star 7500 years ago.

It will be a cataclysm
unlike anything we've seen before.

A hypernova.

An explosion so powerful,
it'll make a supernova...

seem like a firecracker by comparison.

If there are nearby solar
systems with planets

harboring life, their
days are numbered.

A hypernova spews
so much radiation into space...

not just light, but x-rays
and gamma rays...

that planets that are dozens,
or perhaps hundreds of light-years away...

could be stripped of their atmospheres
and bathed in deadly radiation.

It would wreak havoc in thousands
of nearby star systems.

Right about now,
you're probably asking yourself:

"Are we safe?"

If Eta Carinae blows up,
what happens to Earth?

Rest assured, Earth will be just fine.

Remember, we're 7500 light-years away
from Eta Carinae.

The intensity of radiation
from a star, even an

exploding star, falls
off rapidly with distance.

But still, Eta Carinae in its death throes
will put on quite a show.

It will light up the night
of the southern hemisphere...

with the brightness of a second moon.

The most dramatic swan song
a star can sing.

Our ancestors worshiped the sun.

And they were far from foolish.

It makes good sense to revere the sun
and stars, because we are their children.

The silicon in the rocks, the oxygen
in the air, the carbon in our DNA...

the iron in our skyscrapers,
the silver in our jewelry...

were all made in stars
billions of years ago.

Our planet, our society,
and we ourselves are stardust.

Well, what is it that
makes the atoms dance?

How is the energy of a star transformed
into everything that happens in the world?

What is energy? We're awash in it.

When hydrogen atoms fuse inside the sun,
they make helium atoms.

And this fusion emits a burst of energy...

that can wander inside
the sun for 10 million

years before making
its way to the surface.

And once there, it's free to fly straight
from the sun to the Earth as visible light.

If it should strike the
surface of a leaf, it

will be stored in the
plant as chemical energy.

Sunshine...

into moonshine.

I can feel my brain turning
the chemical energy of the wine...

into the electrical
energy of my thoughts...

and directing my vocal chords to produce
the acoustic energy of my voice.

Such transformations of energy
are happening everywhere all the time.

Energy from our star drives the wind
and the waves and the life around us.

How lucky we are to have this vast source
of clean energy...

falling like manna from heaven
on all of us.

To Annie Jump Cannon,
Henrietta Swan Leavitt and Cecilia Payne...

for blazing the trail to
modern astrophysics.

And to all the sisters of the sun.

There's no refuge from
change in the cosmos.

Some 10 or 20 million years from now...

it'll seem for a cosmic
moment as if Orion

is finally about to
catch the seven sisters.

But before he has them in his clutches, the
biggest stars of Orion will go supernova.

Orion's pursuit of the Pleiades
will finally end...

and the seven sisters will glide serenely
into the waiting arms of the Milky Way.

We on Earth marvel, and rightly so,
at the return of our solitary sun.

But from a planet orbiting a star
in a distant globular cluster...

a still more glorious dawn awaits.

Not a sunrise...

but a galaxy rise.

A morning filled with 200 billion suns.

The rising of the Milky Way.

An enormous spiral form
with collapsing gas clouds...

condensing planetary systems,
luminous supergiants...

stable middle-aged suns...

red giants, white dwarfs,
planetary nebulas...

supernovas, neutron stars, pulsars,
black holes.

And, there is every
reason to think, other

exotic objects that we
have yet to discover.

From such a world,
high above the Milky Way...

it would be clear, as it is beginning
to be clear on our world...

that we are made by the atoms
and the stars...

that our matter and our form are forged
by the great and ancient cosmos...

of which we are a part.