Original subtitles

We're at the edge of a spiral galaxy,

far from the galactic core.

This small planet is our Earth,

its pole crowned with a circle of "Northern Lights".

The whole planet glowing in the infrared warmth

of a star we rarely think about, a star we call "Sun".

It is almost midwinter in Ireland.

Soon the sun will begin its journey back from the south.

Waiting for the Sun is a Stone Age building,

older than the Pyramids of Egypt.

Above the entrance is a mysterious skylight built by people

who understood very well the ways of the Sun.

Sunrise on the shortest day of the year: The winter solstice.

On that day, the first rays of the sunrise spear through the skylight

and down a perfectly aligned passageway to penetrate to the room

at the core of the structure, to mark almost magically,

but with great precision, the beginning of a new year.

This is the oldest room on Earth, its careful alignment perhaps

the oldest evidence of scientific thought ever found.

Our Sun is a star, one of billions.

It has shone for five billion years

and will shine for five billion more.

For us, it is the great engine of life.

If you're near the pole, the summer days never end.

The sun shines through midnight

and new days are born out of days that never ended.

There, you can almost feel the Earth rolling around beneath the sky.

Most ancient civilizations recognised the Sun

as the source of all life and called it God.

They observed it with care,

sometimes setting up stone markers to send that knowledge through time.

The one sure prediction in an unpredictable world:

The Sun sets, but the Sun also rises.

Any break in that pattern once caused terror and foreboding.

The Sun is 400 times bigger than the Moon.

But the Moon is 400 times closer.

So on those rare occasions

when the Moon passes exactly between us and the Sun,

the disk of the Moon exactly covers the disk of the Sun.

Masked by the Moon, the Sun reveals its mysterious corona.

The eerie streamers of light heightened the mystery

and increased the power of those who could predict these awesome events.

We have the eclipse records

kept by the astronomer priests of ancient Babylon.

They are so accurate that scientists today use them

to correct computer programs.

The Sun Gate at Tihuanaco in Bolivia:

A fragment of a sun cult dating back more than 1,000 years.

Nearby, high in the Andes, is lake Titicaca,

and in the center of the lake, The Island of the Sun.

On the island, this rocky hill was once plated in Inca gold.

Here the sun god anointed the first Inca

and send him north through the Andes,

to create an empire that grew to be as big as Europe,

with many dazzling cities,

among them, the lost city of Machu Pitchu.

Like the people of ancient Ireland,

the farmers of the Inca Empire needed an accurate calendar.

If they planted their terraces too soon,

the corn would freeze in the groundl

too late, and it would never ripen.

There is one building at Machu Picchu that is like no other:

The Torreon.

Its curved wall is pierced by an opening that is so aligned

that it will project the first rays of the midwinter sunrise

precisely to the edge of a carved rock,

and so mark the first day of the Inca year.

The highest outcrop at Machu Pitchu

is called "The Hitching Post of the Sun".

From it, the Incas imagined a great leash

stretching out to hold onto the Sun

as it paced the horizon like a restless Lama.

The ancient Greeks imagined the sun as a god

who drove his chariot across the sky,

but they abandoned their myths for a more rational cosmos

nearly two and a half thousand years ago.

Aristotle taught that the world was round

and theorised that the sun and planets

must be carried through space, embedded in crystal spheres

that were nested around the Earth, like Russian dolls.

He assumed that the Earth was at the center of the universe,

misleading astronomers for centuries.

By then, the all-powerful church

had placed God in Aristotle's seventh heaven.

The cathedral of Frombork on the shore of the Baltic Sea.

At about the time Columbus sailed for America,

a young astronomer struggled here

with the contradictions of Aristotle

as he observed the tracks of planets across the sky.

To Nicholas Copernicus, it made no sense,

until he made one of the great intellectual leaps of all time.

The sun was the center of a system,

the Earth, merely one of its planets.

It was a cosmos awesome enough

for one of humanity's great minds: Galileo Galilei.

Galileo was the first person to point a telescope at the stars.

He saw that Copernicus was right.

Galileo found that the Sun

was not the flawless orb required by dogma.

It was as spotty as a teenager.

The sun was at the center.

But the church had no intention of vacating center stage.

Galileo was put on trial before the Inquisition,

a court that had the power to burn him at the stake,

to inflict any torture.

They showed him their instruments,

and the threat was enough.

The most respected scientist of his day

signed a confession that he knew was nonsense.

Dogma had triumphed.

The cathedrals of the new age were the cathedrals of science.

And new instruments were built, not for torture,

but to find new galaxies,

to peer into the heart of the Sun.

At first researchers could see only the bland white face

that is revealed by visible light,

and sometimes the procession of mysterious dark spots

that some took to be clouds.

The Earth's atmosphere clouded and distorted the image.

But in time, the great solar telescopes,

like Big Bear in California,

blew away the notion of a placid unchanging Sun.

People wondered what the Sun was made of,

but never expected to know.

It's 93 million miles away!

The answer was discovered in the colors of the sunlight itself.

As each element burns,

it consumes its own distinctive color,

writes its own signature in dark lines across the spectrum.

Our sun is mostly made of hydrogen and helium,

some carbon and iron and other elements,

much the same elements as we are made of,

but that's not so surprising, since we were born of the same stars.

There had been a hundreds of stories and theories

to explain the aurora.

But no one suspected a connection with the sun.

An eccentric Norwegian scientist, Kristian Birkeland,

built his own world in a glass box,

electrified his model Earth with its own magnetic field

and showed how electrons from the Sun

could ignite earthly auroras.

And he predicted that they would be identical

and simultaneous at both poles.

Birkeland was right,

but proof of his theories, and so much else,

had to wait until we could step into space.

Space has given us new eyes.

Everything we glimpsed before can be seen anew.

A stormy night as we fly towards the coast of Australia:

We are heading south, out over the Southern Ocean,

towards Antarctica.

This is SOHO.

Built in England and France for the European Space Agency,

with instruments from Europe and the U.S.A.

It was launched by NASA

and parked a million miles from Earth at a point

where the gravity of the Earth exactly balances

the gravity of the Sun.

SOHO shows us the Sun as we have never seen it before.

A wider lens.

The image is 30 million miles wide,

the Sun blanked out,

so we can see the corona jetting out into space.

Here, the two images are combined.

Billions of tons of particles fired into space

at a million miles an hour,

sometimes, directly at our Earth.

We are saved by our magnetosphere,

an invisible magnetic shield that protects us

from the lethal particles that are spewed out

by our Sun and other stars.

This solar storm pushed the edge of our magnetosphere

twice as close to Earth as usual,

disabling satellites, wiping out radio communications worldwide,

and sending voltages soaring dangerously

in everything from power transformers to oil pipelines.

Repairs after the last Solar Maximum

cost more than $1 billion.

A century ago, space storms could pass unnoticed.

But 2,000 satellites have been launched

since the last Solar Maximum.

Every aspect of our civilization

depends on their uninterrupted functioning.

Sun storms can kill satellites.

They can also kill astronauts.

For long space flights, a dangerous storm

is a practical certainty,

and finding effective protection a necessity.

But at present, the best we can do

is try to avoid Solar Maximum.

The Sun has north and south magnetic poles,

just like the Earth.

But every 11 years, those poles reverse

with unimaginable violence.

That peak of violence is called Solarmax.

The 11-year cycles can change, even vanish completely.

About 1,000 years ago, the Sun was unusually active.

It was about the time the Vikings settled

a grassy new land they called "Greenland".

Thousands moved there, but then the Sun grew quiet

and the solar cycles almost stopped for a hundred years.

The average fall in temperature was just two degrees,

but it was deadly enough.

The bays froze over, the people starved.

No one survived.

Recently, scientists have found that suns like ours

normally produce a superflare about once every century.

A superflare would destroy half of our ozone layer,

and the entire satellite fleet.

We are fortunate that our Sun

seems to be much more stable than most other suns.

A tiny new spacecraft called TRACE

brings us a view of the Sun

that is still largely beyond the scope of our understanding.

Magnetic field lines burst through the surface,

to unleash in seconds as much energy as the world uses

in a million years.

On the horizon is the mountain that Native Americans call

"The Pivot of the Sky".

This is Kitt Peak in Arizona,

site of the National Solar Observatory.

The small telescopes on the spacecraft

work in harness with large telescopes on Earth.

The combination produces results that are much more valuable

than any of them could obtain alone.

This is what we call the surface of the Sun,

the layer revealed by visible light.

Embedded in it are two sunspots,

each big enough to swallow the Earth.

With filters and computers, we can peel away the layers

as we'd turn the pages of a book,

searching for a better understanding

of the the forces that shape our universe.

And more urgently, that shape the climate of our world.

We urgently need to know more.

So an International Solar Terrestrial Program was devised,

linking satellites and a chain of observatories

to create one "Great Observatory".

A surprising discovery was the singing of the Sun.

As the sun hums to itself, a million pure tones change

as they resonate through the plasma,

revealing to us tides and currents far below.

In a Munich laboratory, final testing of a satellite

that is destined to be flown into the eye of a solar storm.

It is one of four identical spacecraft

designed to fly together in formation

to capture a unique 3-D picture of the space environment.

The formation encloses a pyramid of space

and monitors everything that happens inside that space.

The tiny fleet will give us an unprecedented view

of the interaction of the solar wind with our magnetosphere,

from the bow wave to the distant tail.

As the millennium approached,

everything was in place to make the Solarmax of 2001

a milestone in our search for understanding of the Sun.

But a mistake was made in a command sent to SOHO.

In a split second,

SOHO went from being the flagship of the space fleet

to a useless piece of frozen junk.

The SOHO team refused to give up.

From all over Europe and the U.S.A.,

they rushed to the control center at NASA

to brainstorm ideas, working to save their ship.

Months passed.

Dozens of schemes were tried.

It was like trying to raise a submarine with a fishing line.

But against all the odds,

a signal hooked into the control computer.

Delicately, painstakingly, tiny surges of solar power

thawed out fuel for the thrusters.

Incredibly, the whole array of critical instruments

proved tough enough to survive being frozen solid for 3 months.

SOHO came back from the dead.

In a nation where land is at a premium,

15,000 acres of virgin forest preserve the shrine at Ise.

It is Japan's most sacred shrine,

the Shrine of the Sun Goddess,

and every year, the Emperor pays his respects.

No one but the emperor and the closest members of his family

can enter the inner shrine.

It was the Sun Goddess herself

who appointed the first emperor of Japan.

So even today,

one of the world's most advanced nations still has a Sun King.

Every morning of the year, people travel to sacred places

and rise in the darkness to await the daily miracle.

Every sunrise brings hope.

For some, it's the hope that we can learn to do

what the humblest plant can do:

Make clean and abundant energy directly from sunlight.

This aircraft is on its way

to an altitude of more than 80,000 feet,

twice as high as a jumbo jet.

It is powered only by sunlight.

It set a new world record

and poses a new challenge.

The challenge of finding cheap and practical ways

of using the Sun and the sun-driven winds

to bring clean and inexhaustible power to the machines of Earth,

machines that fit as naturally as trees and flowers

into the web of life.

It is winter in the high Andes,

just before sunrise on Midwinter's Day:

The first day of the Inca calendar,

and by some counts, the first day of a new millenium.

It is time to prepare for the festival of Inti Raymi,

time to celebrate the Sun.