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We're now in our sixth decade of hurling things into space.

Intrepid little machines that have gone where we could not.

So where to next?

What even more inconceivable odds will we put them up against?

How about a mission to touch the sun?

To explore exotic oceans on distant moons?

To whiz at impossible speeds to neighboring stars?

Preparing the way for humans to follow?

And in the end, to answer that ancient, life and mind-altering question,

are we alone?

What we can say today is that statistically,

there are more planets out there than stars.

Every star has one or more planets.

If there's life elsewhere in our solar system, that would

imply that life must be common throughout the universe.

These are the stories of a lonely blue marble, sending its

intrepid little machines to places no human can yet go.

To the far ends of the solar system and beyond.

We've been almost everywhere in our solar system.

But we haven't been here.

To its most important body.

For obvious reasons.

It's ridiculously hot.

And the radiation streaming out of our star is insanely dangerous.

But NASA has decided it's time to take on the challenge.

They really do call it their mission to touch the sun.

And it's as crazy as it sounds.

The rugged little probe that's going to take on our star is called Solar Probe Plus.

And with a $1.5 billion investment, it has to

be stronger than any probe we've ever built.

Solar Probe Plus will fly.

It will eventually get into as close as 10 solar radii from the sun.

Earth's at 212 solar radii.

So it's very close to the sun.

Very hot.

So you have to hide everything behind a thermal shield to protect it.

So that means that we can go to about 3.6 billion.

While moving at a mind-blowing 430 miles a second, Solar Probe Plus will get seven

times closer to the sun's surface than any other probe.

And actually dip into its atmosphere.

The corona.

So how on earth is a space probe supposed to survive these impossible conditions

close up, above and beyond anything any other craft has ever faced?

Somehow, incredibly, just four and a half inches of carbon composite material will

shield the sensitive instruments from the

2,500 degree Fahrenheit heat it will encounter.

And the interior of the spacecraft will remain at room temperature.

The sun's atmosphere, the corona, is thousands of times hotter than its surface.

Which is a balmy 6,000 degrees.

It defies common sense.

Not to mention all the best computer simulations in the world.

And somewhere in that seething cauldron, the mysterious solar wind is born.

Energized.

And hurled away from the sun at a million miles an hour.

This stream of charged particles, like electrons

and protons, fills the whole solar system.

Bombarding all of the planets.

Including ours, of course.

And I think the science community finally concluded that unless we get the ground

truth with a solar probe in the vicinity of the sun, we'll continue to argue about

modeling, whether this process is more important than that, and so on.

One of the key questions about the sun is that

the wind blowing out from the sun is supersonic.

It's a million degrees, yet it comes from a

surface which is only thousands of degrees hot.

How does that happen?

What is the source of energy that heats the corona and causes

it to expand at a million miles per hour away from the sun?

And where the wind is picking up its speed as it's leaving the sun?

The sun has tantrums.

Sending out raging flares of solar wind that can light

up the sky at the Earth's poles in glorious fashion.

Or wreak deadly havoc.

It's estimated that a big solar storm hitting the Earth could wipe out much of

our electrical grid, causing several trillion dollars worth of damage that

would take years, even a decade, to recover from.

And we'd have maybe 12 hours to prepare.

Unless we learn enough about the sun to predict its crazy weather.

Well, it turns out that if you have a big solar eruption, that can perturb the

ionosphere and introduce an error in the determination

of the location by GPS satellites on the ground.

So, think of a situation where we have a huge solar eruption, and we're relying on

guiding tens of thousands of flights onto airports, and then all of a sudden,

you know, the thing gets shifted by four or five meters, one way or another,

on the runway.

They'd better get a move on.

Solar Probe Plus has to launch in a 20-day window in the summer of 2018.

And then it will take years of orbital pirouettes, including seven Venus flybys.

Getting incrementally closer with each pass.

Until finally the probe will skirt the edge of the corona for three orbits.

Once Solar Plus One has touched the sun and hopefully gathered enough data to help

us predict our star's terrifying moods, it'll go out in a blaze of glory.

A swan dive into the sun for a fiery death.

Transmitting valuable data as it makes the ultimate sacrifice.

And touches the sun.

But you know, it's our own star.

And it is the first mission to a star.

For me, I mean, that would be something that I could never

even dream of when I started in this business 55 years ago.

But there is one glorious question out there, beside which

all of the bright mysteries of the sun pale in comparison.

That question is, of course, is there life in the solar system?

Beyond the bounds of our beautiful, thriving planet?

If there's life elsewhere in our solar system, if life evolved independently on

two different worlds, that would imply that

life must be common throughout the universe.

So far, humanity's long-standing hopes of finding life, even civilizations on our

nearest neighbors, have been crushed by cruel realities.

Venus is a place of true fire and brimstone, surface temperatures of 900

degrees, and pressures 92 times that on the surface of the Earth.

There are no canal-filled cities full of busy little green men on Mars.

Our brilliant rovers have found evidence of

water, and perhaps the building blocks of life.

But no critters.

It's all about the water.

But it's turning out to be harder and harder to

find among the rocky little planets nearest the Sun.

Everywhere on Earth that there's water, there's life.

Oceans inside of Europa, Enceladus, and other icy

satellites mean that there's the possibility for life.

What we're trying to understand in these icy moons, do

they have the ingredients necessary for microbial life?

So water, the right chemicals to build organic

molecules, and the chemical energy that could power life.

And the giants, Jupiter and Saturn, and their sisters, are massive,

seething, intensely radioactive balls of gas,

completely inimical to life as we know it.

Then, hope came from the most unexpected of quarters.

We knew the gas giants had many moons.

But we expected them to be drab, pock-marked, sterile worlds like our own moon.

We could not have been more wrong.

And while at JPL scientists could not turn away from the groundbreaking images,

it was a graduate student who noticed there was something more than meets the eye.

And she said, Hey!

Come and look at this!

And people said, Oh my God, volcano!

Before the reeling earthlings could get their

heads around Io, they had another nasty shock.

Europa.

This Jovian ice ball moon was shiny and smooth, and beautifully etched with

patterns that looked like cracks in an icy shell.

As though the ice were moving, shattering, skating over something.

Something like a liquid water ocean.

We are really fascinated by the idea that Europa and Enceladus have global oceans

underneath this icy outer layer on these moons.

And we've been thinking for a long time, well,

water's been there for four billion plus years.

The Great Galileo Probe.

The first to orbit Jupiter.

Only added to the evidence of Europa's internal seas.

And found indications that the two other moons,

Ganymede and Callisto, might have the same.

Europa and some other moons of the outer

solar system are in somewhat eccentric orbits.

They get a little farther and then a little closer to their parent planet.

And this causes them to stretch out a bit when they're

closer, and contract a bit when they're farther away.

So this creates a flexing, tidal flexing as they go around their parent planets.

And that generates heat.

Kind of like rubbing your hands together generates heat.

Which can power the volcanoes at Io or keep an ocean within Europa liquid today.

Finally, in 2013, the Hubble telescope captured a plume of

what might be water spewing out from the surface of Europa.

More recent tests hint that those dark lines could be

salt, charred by the intense radiation from Jupiter.

Salt water would mean that the ocean is in contact with some sort of rocky,

mineral-rich seafloor.

For many astrobiologists, this was all they needed to know.

Those oceans on those moons might also have vent systems on the bottom.

Life might, in fact, have started there.

And so we've been thinking and thinking about how do we get through those

kilometer-thick layers of ice to sample the oceans?

This science is so vital, NASA has already committed

to going to Europa sometime in the early 2020s.

A radiation-tolerant spacecraft just bristling with scientific equipment would

enter into a long, looping orbit around Jupiter.

To perform repeated close flybys of Europa.

Part of the equipment?

Ice-penetrating radar antennas that could see into the inner ocean.

NASA is planning a new mission to Europa, to orbit Jupiter and fly by Europa many,

many times with specialized instruments designed to understand the detailed

composition of its surface and of molecules that

are kicked up into Europa's very tenuous atmosphere.

And to get at the detailed geology, magnetic field, gravity field of Europa.

So we're going to have a really good idea

of the potential habitability of this world.

Some have conceived of ways that we might someday drill or

melt down through Europa's ice shell and into the water.

But first we want to understand how thick is that ice shell?

Are there thin spots we might go into?

Are there lakes within the ice shell that we might go into?

And we need to develop the technologies that would be

required to get down to that water and sample it directly.

But of course, that's all a tease for the big event.

To dip a toe and maybe even dive into that incredible ocean.

If we were to find life at Europa, it would just revolutionize our

understanding of our place in the universe.

No longer would we be alone.

But what if life needs liquid to evolve?

Not liquid water in particular.

That's where an underwater submarine has emerged from

the incredible imagination of planetary explorers.

One that would ply the seas of Titan, a giant moon of Saturn.

Titan looks remarkably like Earth.

The difference is Titan is very cold.

So we've been surprised to find that Titan has surface lakes.

Cassini has sent us some images of that moon in false color representations.

And you squint at it a little bit and it looks like Titan.

You're looking at Northern Michigan, the lake country, right?

All of these lakes, but they're not water.

They're made out of organics.

They're made out of methane and ethane.

Because it's so cold there, water would be frozen.

There is apparently water underneath the surface of Titan.

It's mixed with ammonia.

So it's a really weird world.

There are a lot of interesting ideas for future exploration of Titan.

There could be an orbiter.

There could be a balloon that floats around in the atmosphere.

Even the possibility of sending something to float

on or even investigate under the lakes of Titan.

The Titan Mare Explorer is currently on hold, but may be reactivated as part of a

larger Titan-Saturn mission in the later 2020s.

This clever boat-slash-submarine would dive into Lygia Mare, the moon's largest

lake, and examine its chemistry, depth and dynamics with an eye,

of course, toward the potential for utterly alien methane-based life.

Wow.

Can we have a hydrocarbon-based life form?

People do speculate about that.

And what would it teach us?

It would go, Wow.

Wow.

There's another way to do biology.

Huh.

Why didn't it happen that way here?

It would be a great a-ha moment.

So, if there's life out there circling around another star, how do we manage to

drop in with a casserole and welcome them to the neighborhood?

The distances are daunting, to say the least.

Picture our intrepid Voyager 1.

Four decades after its departure from Earth, only now leaving our solar system,

at a leisurely pace of 38,000 miles per hour.

If Voyager could keep going indefinitely and was pointed in the right direction,

which it's not, it would take the veteran probe a little over 70,000 years to make

the journey to our nearest star, Alpha Centauri.

Seventy thousand years?

At that rate, nobody here on Earth is holding their breath.

But what if we could get some very special probes to that star in 20 years?

Believe it or not, some of the biggest brains and the largest wallets in the

solar system have just announced their intention to do just that.

People like Stephen Hawking and Russian gazillionaire Yuri Milner.

But would you believe me?

I do know that the time is to start now, given that

technology is available to launch a little spaceship.

Yes, you heard that right.

Space chips.

Not space ships.

Dubbed Breakthrough Starshot, the $100 million initiative plans to send a

mothership into lower orbit, then toss a payload of thousands of tiny,

centimeter-sized one-gram chips, fitted with light sails, into open space.

Each chip will direct its three-foot square solar

sail and wait for the light to be turned on.

A really big light, a laser beam of extraordinary

size and power, fired up from Earth.

The idea that we could use light pressure to accelerate these tiny spacecraft up to,

say, 20% of the speed of light, so that we could reach the Alpha Centauri

system, that's what he was going for, in 20 years or so.

The laser-propelled manor craft could theoretically reach speeds of 20% of the

speed of light, covering the 4.3 light-years to

Alpha Centauri in a jaw-dropping two decades.

We've just been amazed by the images and the data that have come back from flying

by Pluto with one spacecraft and a number of instruments.

Can you imagine the riches that we would get from data coming back from,

not one, but dozens or hundreds of these little star chips going by the Proxima or

the Alpha Centauri system and taking a close look at this planet?

So, okay, maybe technology for the giant lasers isn't quite

lolling around in our pockets yet, but it isn't far off.

Alas, poor Voyager.

Can you imagine the exchange as the swarm shoots by our intrepid but antiquated

car-sized workhorse at 100 million miles per hour, carrying equipment tens of

thousands of times more sophisticated, in cornflake-sized packages?

Are they crazy?

Hey, they laughed at Jules Verne.

Envisioning a manned moon missile in 1865.

And look what happened a century later.

Who knows what we can accomplish in another hundred years?

This is the century of biology, but it's really

the century of biology on Earth and beyond.

In this century, we're going to be answering some of these questions about

life in our own solar system by going there, by actually looking for biomarkers,

by flying through plumes and bringing material back

from oceans underneath the icy outer coverings of moons.

We're going to be exploring the nearest stars.

NASA Jet Propulsion Laboratory, California Institute of Technology NASA

Jet Propulsion Laboratory, California Institute of Technology