We humans have come a long way.
Travelling our world in search of new lands.
Spreading to every corner of the globe.
But the time has come to look to new destinations.
To go, once more, into the unknown.
This is the story of our journey in space.
We will fly to the stars on a ship that sails on sunlight.
We'll explore the most distant edges of the cosmos
by taking a roller-coaster ride through the fabric of our universe.
We'll discover the machine that has charted the heavens as never before.
It's the voyage of a lifetime, a voyage to our future in space.
We've always had the urge to explore.
Our ancestors journeyed into the unknown to discover new lands.
And now it's time to do it again.
And this time,
it's not a voyage between continents.
This time, it's a voyage to the stars.
As our telescopes get ever more powerful,
they've shown us a universe of unimaginable beauty and power.
Vast clouds where new stars are born.
Strange galaxies.
Even tantalising hints of new worlds.
But they have also shown dangers.
Disasters so huge, they could destroy the Earth in seconds.
Space is full of terrors... and wonders.
But will we ever see them for ourselves?
(MISSION CONTROL) We have lift off!
It's less than 50 years since we took our first steps into space.
Since then, thousands of rockets carrying hundreds of people have made
the ten-minute flight into orbit.
Astronaut Story Musgrave is one of a new breed of space adventurers.
When you see a launch from the outside,
it's a rather glorious thing.
Inside, it's the absolute opposite of that.
It's 137 decibels. It's shaking. Everything is shaking.
You have a solid block of boosters that are really pounding the vehicle.
You have atmospheric turbulence
that adds another shake, rattle and roll.
You're basically in a small closet
with belts and straps and helmets and gloves and parachutes, survival gear.
That's all over you and, at the same time, you're being shook.
And it can't help but pass through your mind
that you just want the whole stack to hold together.
You're along for the ride and you want to survive.
So, it's not a joyride for me.
It's what I need to go through to get into the serenity
and the celestial dance of zero gravity.
(OVER RADIO ) Hello, Houston, we are inspired.
We are ready. Let's go and fix something.
We are becoming space farers.
It's a strange and unfamiliar world.
But for the privileged few who go there, it is an experience
they can never forget.
Space walking is more like dance than anything.
You choreograph every move.
You choreograph every finger, every toe, every body position
and how you will do all of that.
It's just as precise as a ballet.
Going into space is opening night at the ballet.
During a space walk,
I live to look at my feet.
You see your boots going 25,000 feet per second.
You see them going down the road.
If you ever want to play Superman, that's where to do it.
We stand on the edge of space.
Our most ambitious project is testament to what we have achieved:
the international space station Freedom.
But it's surprisingly close to home.
It is floating less than 400 kilometres above our heads.
The furthest we have travelled into space is this.
In 1969, we set foot on the moon.
(NEIL ARMSTRONG) That's one small step for man, one giant leap for mankind.
For the first time ever, we looked back at our home
from the surface of another world.
It's amazing to think that people have actually walked up there.
The trouble is, it may have been a giant leap for us,
but in the vastness of space, it really was one small step.
Although we humans haven't reached any further than the moon,
our robot ambassadors are already reaching for the stars.
Where we cannot go, we have sent machines.
This is the Voyager probe.
Nothing we've created has travelled so far.
It's left our solar system on its way to the stars.
Look at how far it has gone.
Voyager left Earth in 1976.
It passed Jupiter, then Saturn.
Now it has left all the planets far behind.
After decades in space, it's 14 billion kilometres from Earth.
It's an impressive journey until you consider this.
On this scale, the nearest star to our solar system is way over there.
In fact, it's over 100 kilometres away.
To reach it would take Voyager another 25,000 years.
At Voyager's speed, even reaching the nearest star
is an impossible journey.
But perhaps there is hope.
It's easy to forget that in one lifetime we've gone from this...
..to this.
And in our quest to reach the stars,
some scientists believe the answer could be to go from this...
..to this.
Deep Space One.
Its secret is a new kind of engine - the ion drive.
And it is the passion of NASA scientist Marc Rayman.
The idea for ion propulsion was around from before I was born,
but I first heard of it on Star Trek.
They were using ion propulsion, and Spock said,
''Configuration unidentified.
''Ion propulsion. High velocity. Unique technology.''
And I thought, ''Well, this is really amazing,
''but I'll never see anything like that in my lifetime.''
But in 1998, Marc's dream became reality.
Deep Space One.
But what is it that makes the ion drive so different?
Compare it with a conventional rocket.
The rocket fuel burns with tremendous force.
And, as it thrusts down, it pushes the rocket up.
In the lab, Marc Rayman watches a prototype ion drive in action.
Instead of tonnes of rocket fuel,
the engine uses a few grammes of a gas.
It gives the gas an electric charge and spits it out atom by atom
at incredible speeds, creating a seemingly gentle blue haze.
The ion drive doesn't have the raw power of a rocket.
It has something better - staying power.
It's a bit like the hare...
..and the tortoise.
Conventional rocket engines create huge thrust and awesome acceleration.
But they burn through their entire fuel supply in just a few minutes.
After that...
it's all over.
The ion drive is nowhere near as powerful.
In fact, it would take Deep Space One four days to get from nought to 60.
But the reason Deep Space One is the fastest spacecraft ever
is because it has been accelerating for almost two years.
When we communicate with that craft out so far in the solar system,
to think that our baby is out there, this little spacecraft that we built.
I just...I think it's really amazing.
Ion drive spacecraft will be fast enough to chase down comets
or travel round the planets in our solar system in a few months.
But even ion drives don't last forever.
Eventually, they too will run out of fuel.
To travel further, to reach the stars, we'll need something new.
And it may be based on one of the oldest technologies we know -
the sail.
Long ago, the limitless power of the wind carried our ancestors
to new worlds.
In the future, we may use the same idea to travel to the stars.
On sails that catch nothing more than sunlight.
A solar sail, using only the light from our sun.
Many scientists are sure that this is the future of space travel.
One of them is Les Johnson.
The sun puts out photons - light.
Standing here on a sailboat,
the photons that are falling on us are pushing on us.
But the push is so slight that we don't feel it.
The other forces around us are so much higher that it's not noticeable.
But in the vacuum of space, if you have a large and light enough material,
the pressure exerted by solar photons can cause it to move.
To see if sunlight could drive a sail through space,
Johnson and his team built this - a man-made sun.
In front of me, we have a simulated sun,
about three times wider than the sun is at the Earth.
That's the reason I'm wearing these UV protecting sunglasses.
It could damage my eyes if I was to accidentally look into the beam.
They are testing the ultra-thin, ultra-light material they would need
to make a real solar sail.
It's mounted in the full glare of their sun.
As you look in there, you can see it slowly rocking back and forth.
What is causing that is the photon pressure as it's pushing on the sail.
Incredibly, it works.
This piece of sail material is being moved by nothing more than light.
Based on work that's being performed around the country,
solar sail technology is getting to the point
where very soon, we'll be flying it in space.
To reach the immense speeds needed to travel from star to star,
the solar sail must start its voyage with as big a push as possible.
It must fly as close as it can to the source of its power - the sun.
It's a dangerous manoeuvre,
but if it works, the craft will whip around the sun
and hurtle out into space...
..at almost three quarters of a million kilometres an hour.
A solar sail could reach the nearest stars in just decades.
It's a truly impressive start, but is it enough?
Our galaxy is a very big place. To get from one side to the other,
even using a super-fast solar sail travelling at incredible speeds
would still take 2.5 million years.
And our galaxy is only one of billions that make up our universe.
And this...is the final frontier.
If we ever want to be truly star travellers,
we'll have to take a completely different approach.
We're going to have to learn how to manipulate
the very fabric of space itself.
Some scientists believe there may be
a quicker way to get around the universe.
One of them is cosmologist Peter Coles.
When early man first began to explore his environment,
he would run into fundamental barriers when he got to mountains.
Mountains are not easy to cross
when you're faced with a wall like these mountains around us.
You've no choice but to go around them or over the top.
Now, these days, it's exactly the same thing with space travel.
If I'm going to explore the galaxy,
then the distances I have to travel are truly immense.
When it comes to space travel, we're still very much in the Stone Age.
The answer could be to take a shortcut.
Don't go round the obstacle, go through it.
If you travel through space,
you are fundamentally limited by the speed of light.
But the laws of physics might have a kind of loophole in them
which allows us to travel slower than the speed of light,
but still travel huge distances quickly.
The way we can accomplish that is through a wormhole.
A wormhole is basically a tunnel that takes a shortcut through space-time.
Here to the nearest star could be connected by a short tunnel.
Wormholes may sound like science fiction,
but creating one may just be possible.
First, we'd have to harness
the incredible forces of an exploding star
and use them to punch a hole through space.
We'd need exotic forms of energy to keep the tunnel open.
But the science IS sound.
At least in theory, it IS possible to create a tunnel
that reaches clear across the universe.
Experiments have already begun to try and build the first tiny wormholes.
In theory, wormholes will take you across the universe...
..in literally no time at all. Instant travel...
..anywhere!
A wormhole could just as easily have taken me halfway across our galaxy.
But how do you decide where to go? For that, you're going to need a map.
Space, as we've discovered, is very big.
But Profesor Brian Boyle and a team of Australian astronomers
may have the beginnings of an answer.
They are creating the biggest map imaginable - a map of our universe.
Traditionally, astronomers looked at the universe
as a flat map on the plane of the night sky.
You can think of it like a map of the Earth.
For a hiker, a flat map is no use at all.
A flat map wouldn't tell you
if there was a mountain in the way, or a huge ravine.
In the same way, the hikers of the future
will need a three-dimensional map to guide them around.
To create a three-dimensional map,
Boyle and his team had to develop a unique piece of equipment.
Ten years to make, weighing over three tons,
the device uses over 600 fibre optic cameras.
The whole apparatus is delicately manoeuvred into position
high up on one of the biggest telescopes in the world.
Everything's connected up. We're ready. Fibres in position.
We'll take the telescope back up to the top
and wait for the stars to come out.
Every night, the telescope looks at a new patch of night sky.
And, for each point of light it sees,
a robot places a single fibre optic camera.
The light from the object is measured
and its distance from the Earth accurately calculated.
So far, the tireless robot has looked at and logged the positions
of tens of thousands of stars and galaxies.
Bit by bit, it has pieced together
an unequalled picture of the universe.
And this is the result.
For the first time ever,
we can see what our universe looks like in three dimensions.
When the map was first created,
I was really filled with a sense of a mixture of awe and excitement.
Here I could see, almost developing in front of my own eyes,
the structure of the universe.
Giant archipelagos of galaxies
stretching hundreds of millions of light years
across intergalactic space.
(STORY MUSGRAVE) The day before I'm going to launch from right here,
I go to the beach right over there. I go to the ocean.
I'm down by the ocean and I'm looking at the satellites crossing overhead.
But I look at those satellites just whizzing along
and I think, ''Tomorrow, that's me!''
I think that kind of thing where you don't know if you're coming back,
you don't know the final outcome
and you don't really know where you'll end up...
You focus on a journey, and that's what carries you forward.
There's a lot out there to explore,
and one day, humanity may be lucky enough to do it.
Our descendants will reach for the stars.
So, the next time you look at the night sky,
remember that space is stranger and more beautiful
than we can begin to imagine.
And, above all, remember this...
..out there in space is our future.