Space's Deepest Secrets

The aurora borealis,

better known as the northern lights,

have mystified scientists for centuries.

The aurora is just magical.

I can't actually explain it,

but you just can't stop watching it.

What we really don't understand is the really big picture.

We have an enormous amount still to learn.

Now an international team

of aurora-hunting scientists is undertaking

a series of pioneering experiments to reveal

what really causes the northern lights'

mysterious colors, patterns, and shapes.

I've never seen this as a scientist before.

It's something fundamentally and profoundly new.

The hunt for aurora could even answer

one of humanity's greatest questions.

Can we detect aurora on planets outside our solar system,

and that might tell us there's life on those planets.

Unlocking the secrets of the aurora

is transforming our understanding of our planet

and our place in the universe.

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The aurora borealis is a magical spectacle of the frozen north...

But despite hundreds of years of investigation,

scientists are still trying to unlock its deepest secrets.

What causes these celestial fireworks?

What can their color tell us about our atmosphere?

And why can they suddenly appear

over unexpected parts of our planet?

The northwest territories in Canada

are the best place on earth to hunt down answers.

For 240 nights a year, when the sun sets,

the northern lights light up this frozen landscape.

aurora hunter Emma spanswick braves the elements

to set up a pioneering piece of aurora-watching technology.

Yellowknife has the best chance of aurora...

Basically, in Canada right now.

It's... It's in the perfect spot,

right in the heart of the auroral zone,

and that's why we came.

Emma has dedicated her career

to revealing the northern lights' deepest secrets.

She's installing a super-wide-angled color-camera.

Its images will help Emma understand

why the northern lights suddenly appear in the night sky.

This is our new color aurora-camera

that's going out for a test tonight.

It's got a 360-degree lens on it,

so we should see the entire lake here,

and, hopefully, some nice aurora.

Emma's camera will complement a network of cameras

that monitor the night sky across a continent

over 3,500 miles east to west.

Minus-2 is pretty comfortable, the right temperature for this.

So, if you get multiples of these cameras

and you separate them by the appropriate distance,

you can stitch them together

and make a great view of the aurora across Canada,

and that's what we're going to do.

The camera needs big horizons

to capture as much of the sky as possible,

so Emma's frostbitten observatory

is in the center of a frozen lake

with no mountains, no trees,

and no buildings blocking the view.

Once the camera is installed,

all Emma can do is sit back

and wait for the aurora to appear.

This is absolutely part of the life of an auroral chaser.

You need a lot of Patience in this line of work,

but it will come out.

It's minus-20 degrees celsius,

and it's going to be a long night.

That's because Emma doesn't know exactly

when the lights are going to appear.

The northern lights are driven by our sun.

93-million miles away,

the surface of the sun throws out a constant stream

of charged particles called the solar wind.

Left unchecked, this wind could strip away earth's atmosphere

and extinguish all life on the planet,

but luckily, the earth has a magnetic field

that cocoons the whole globe.

The magnetic field funnels the solar wind's energy

towards the earth's poles

where it excites the gases in our atmosphere

and produces the spectacular lights we call the aurora.

For four hours, waiting in the cold, nothing happens.

But at 10:45 P.M.,

Emma's camera captures the first glimmer

of what the lights have to offer.

This is exceptionally good news, very exciting.

These time-lapse images reveal a sky alive with color,

dancing to the solar wind's beat,

and this video footage reveals sweeping bands of brilliant,

green light as it unfurls across the night sky.

It looks like it's going to brighten up,

running right across the sky, almost horizon to horizon.

Emma will be up all night taking photos of the aurora,

as she investigates what makes the lights appear

because every few hours somewhere on earth,

for reasons not yet fully understood,

the auroras suddenly burst into life.

And once a decade, the lights can become super-charged

into an even more spectacular show.

They appear suddenly in places completely unexpected,

even as far south as Cuba.

aurora hunters are trying to discover

what forces these arctic-light shows down to the tropics.

The first time I saw the aurora was really in Alaska.

I just stood out for well over an hour in these freezing,

freezing conditions,

and just enjoyed this totally spectacular sight.

In Washington, D.C.,

aurora hunter Nicky fox is investigating

why, for their most spectacular displays,

the aurora appear where they're normally never seen.

If you want to see the aurora,

you will do have to travel north, somewhere cold,

but those are more the events that happen almost every day,

but from time to time, we have these huge solar events

that can drive the aurora down towards the south,

towards the equator.

Nicky's office is NASA's Goddard space center

in Maryland.

She's investigating one of the most extreme aurora on record.

Just before Halloween 2003,

a massive storm erupts from the surface of the sun.

Huge aurora follow just days later.

And what made it so spectacular was it was one very large event,

and then just after it came a second big solar event.

These solar eruptions reveal billions of tons

of high-energy plasma heading straight for earth.

It's sending all this material streaming away from the sun

at millions of miles an hour, right towards the earth,

and we're ready to take the impact,

so we knew two to three days after these events

were first seen on the sun,

something big was going to happen at the earth.

When the solar storm hit,

aurora exploded where they're normally never seen.

It was, you know, at night.

It was 11:00 at night, so it was dark.

And I looked up and I thought, "why can I see a sunset?"

And I realized that what I was seeing

was the red glow in the sky to the north of me,

and there it was, a beautiful red aurora.

Nicky saw the 2000 Halloween aurora

in her backyard in Baltimore.

It gave a clue to why massive solar storms

pushed the aurora so far south.

When it actually comes to the earth,

it is carrying a magnetic field in it,

and the earth also has a magnetic field.

When they're in opposite directions,

they actually connect.

This sudden connection between the solar storm and earth

releases huge amounts of energy into earth's upper atmosphere...

Unleashing the aurora across huge bands

of the northern hemisphere,

lighting up continents that normally remain shrouded

in darkness.

But these storms create more than beautiful light shows.

They can have dangerous consequences.

By the time we see aurora light up the night sky,

it may already be too late.

It may already be too late.

At holloman air force base in new Mexico,

the second weather squadron monitors the sun 24/7

and issues warnings

when a solar storm is on course to hit earth.

Solar storms are very dangerous.

They can knock out our satellite and GPS communications,

can even knock out the power grid.

It rests on the shoulders of staff sergeant David glowacki

to predict when the next solar super-storm will strike.

World leaders should be worried about a solar event.

I don't even think you can put a monetary value on it.

His job is to alert the U.S. air force

each time a solar storm threatens earth,

and before the storm sets the earth's atmosphere alight

with dazzling displays of aurora.

We have a body in this chair from sunrise to sunset,

365 days a year, and if a flare did occur,

we have two minutes' response time

to get that notification out across our network.

Right now, a solar prominence... A huge loop of super-hot plasma,

extending up and out of the sun's surface...

Has caught glowacki's attention.

I'm monitoring this prominence

that's rotating onto the sun's disc.

Yes, sir. This is sergeant glowacki,

calling from holloman solar observatory.

We, uh, have a prominence at north 19 on the east limb.

Thank you. Alright, bye.