Original subtitles

Humans have been explorers since the earliest days...

From our birth in the cradle of Africa

and spreading across the seven continents.

That exploration will never end.

It's something very deep within us as human beings.

This stretches back to the dawn of our species.

And liftoff.

Today, a new breed of explorers

are capturing the first glimpses of worlds beyond our own.

We are absolutely pushing the limits

of everything we know about space exploration right now.

Hang on to your seats,

because the roller coaster ride is on.

Mysterious new images

reveal incredible new discoveries.

Captions by vitac www.Vitac.Com

captions paid for by Discovery communications

January 2016...

NASA releases a new image of a strange structure

on the surface of Pluto.

It appears to be an enormous ice volcano

on what should be a geologically dead planet.

On the flanks of this big summit depression

is the caldera of the volcano.

Nothing like this has been seen anywhere in the solar system.

It's got us baffled.

Now scientists believe that

just beneath this volcano is an entire ocean of water.

The mysterious image that triggered this discovery

is one of thousands

that scientists are still downloading

from a historic flyby of Pluto in July 2015.

Stand by for telemetry.

Three, two, one!

Even today, much of the data from the flyby...

Between 35% and 40%...

Is still up on the spacecraft and no human being has seen it.

We don't know what discoveries will be in them.

How did a team of explorers

become the first people in history

to capture images of Pluto's surface,

and what can explain mysterious new photographs

like Pluto's volcano?

A team of young university students

and scientists set its sights

on the last unexplored planet in the solar system.

You know, if somebody said,

"well, were you all obsessed with Pluto?"

I think we would all have to plead guilty.

At the time, Ralph Mcnutt

is a physics professor at M.I.T.

I think I did always dream of being an explorer.

I'd been a space cadet since I was a kid.

And at that time, Pluto

was just this incredible big question mark.

All we knew was that it was a spot of light

in the sky.

But with a dwarf planet three billion miles away

and smaller than our own moon, even the best telescope images

are too small to reveal any detail.

The best image

from the Hubble space telescope of Pluto is this fuzzy ball

that's about six square pixels by six square pixels.

So, here are these upstart kids

that were saying "we ought to go to Pluto."

We ought to finish out the exploration

"of the solar system."

So, at some point, the moniker "Pluto underground" was born.

And the Pluto underground...

I like to call them the Pluto mafia...

These are the folks who've spent

almost their entire careers studying Pluto.

You know, Pluto is the endgame.

This was our opportunity to finish the task

of the exploration of the solar system.

Young graduate students

united by their fascination with the outer solar system,

the Pluto underground,

want NASA to make their dream a reality,

and one man would lead them there...

Dr. Alan Stern.

We weren't going to answer specific questions.

We were going to collect data sets

with our eyes wide open to see what was there,

literally exploring,

literally flying into the unknown.

The Pluto underground form a plan to fly a spacecraft

within 8,000 miles of Pluto's surface...

Almost 30 times closer than the Moon is to Earth.

As it flies overhead,

the probe will turn and snap the first photographs

of the planet's mysterious terrain.

But the plan faces an uphill battle.

NASA could be doing quicker missions closer to home,

and trying to mount an inexpensive mission

all the way to the edge of the solar system

is a fool's folly.

Alan... Alan is a very unique person.

And, you know, I think this was almost superhuman act

of absolutely dogged determination over the years

that made this happen.

Dr. Stern is hopeful

that the images will solve an ancient mystery.

Pluto orbits in a mysterious region

of space densely packed

with unusual moons, dwarf planets,

and other misfit objects.

The final frontier in the solar system

is the Kuiper belt... This region of leftover objects

from the formation of the solar system.

And Pluto is the largest of those objects.

It's a very important region

for understanding the birth of the solar system.

This means that Pluto

is a 4.5-billion-year-old fossil holding clues

about how our own planet was formed.

The Kuiper belt was discovered,

and Pluto went from being this lone misfit

tinhe outer solar system to the biggest, the baddest,

and the brightest member of that entire population.

This was a very rich scienticif target.

After all, it's a long way away,

so you better have an awful good reason.

In 2003,

the Pluto underground convinces NASA,

and the New Horizons mission is born.

We had a lot of difficulties associated

with getting to Pluto.

One of which is it's three billion miles away.

We're driving to, you know, 33 times

as far from the Sun as the Earth is.

The longer a spacecraft travels,

the greater chance something could go wrong.

So the team wants to reach Pluto within 10 years of launch.

New Horizons spacecraft

was gonna be the fastest ever to leave the Earth...

More than 30,000 miles per hour taking off.

That's more than 50 times faster than a jetliner.

To cross a three-billion-mile ocean of space

required us to travel at this crazy speed.

When I was a boy,

Apollo missions took three days to reach the Moon.

New Horizons was going to reach the Moon in nine hours.

How's that for speed?

To achieve that record-breaking speed,

New Horizons must be light.

The less weight a launch vehicle

has to push against Earth's gravity,

the faster it can go.

The size of a small piano,

New Horizons will weigh just 1,000 pounds.

And it can carry only enough fuel

for minor course corrections.

Once it reaches Pluto,

it cannot slow down and enter orbit.

There is no second chance.

You're flying by. There's no stopping it.

The spacecraft is on a path, a beeline, past Pluto.

Either you were gonna get it or you weren't.

And it's terrifying, to tell you the truth.

But if it works, New Horizons

will capture thousands of images in incredible close-up detail.

Three, two, one.

We have ignition and liftoff of NASA's New Horizons.

It was picture-perfect launch.

It couldn't have been any better.

But still, it was yet another 9 1/2 years

before we finally get to Pluto.

But there's plenty to do while the team waits,

including a close pass of another planet.

We needed to pick up some extra energy

in order to be able to actually get to Pluto on schedule.

We had this opportunity

to fly near Jupiter, steal a little, you know,

gravity assist from Jupiter,

and increase our speed by 20%

and cut three years off the travel time to Pluto.

In February 2007,

Jupiter's gravity propels New Horizons

like a slingshot toward its destination.

After nearly 9 1/2 years of traveling through space,

New Horizons

is a mere 10 days away from its historic flyby.

I get a frantic call from Alan Stern,

the principal investigator,

and I could tell that he was breathing hard,

he was running down the hallway. And he said,

"we've lost communication with the spacecraft."

This had never happened in 9 1/2 years of flight.

How could it be happening today at the last minute,

just on the verge of summiting Mount Everest?

Why now? How? What have we done?

10 days from a historic encounter with Pluto,

the New Horizons spacecraft goes silent.

We have no spacecraft, no signal,

no knowledge of what's going on.

It started to sink in

that we may be experiencing something

that's abnormal on the spacecraft.

And I can't tell you how that feels.

Alice Bowman is the M.O.M.,

or missions operations manager, for New Horizons.

You allow yourself those 10 seconds of feeling,

you know, "oh, my god! What's going on?"

And then, you know, your training kicks in.

Alice was in charge of the recovery effort.

And there was no way

she was gonna let this fail after 9 1/2 years.

Alice scrambles the team to assess the damage,

and they make a heart-stopping discovery.

It turns out that we had overworked

the main computer on the spacecraft

and caused it to reset.

Six months of programming are lost.

Now the engineering team has only a few days

to redo everything.

We knew we could fix it.

The question was, could we fix it

in time for the flyby sequence

that was supposed to start on July 7th?

Over the course of three sleepless days,

the team uploads command codes to New Horizons

nearly three billion miles across the solar system.

We're able to get that sequence or set of instructions

loaded to the main computer...

And we had four hours to spare.

If you've got high blood pressure to begin with,

this is probably a business you ought to stay out of.

Seven days later,

the morning of the Pluto flyby has come.

Hang on to your seats,

be cause the roller coaster ride is on.

As media from across the world gathers

at Johns Hopkins university outside of Baltimore, Maryland,

all eyes are on Dr. Alan Stern.

We passed inside the orbit of Hydra,

the outermost moon of Pluto.

And he's brought an early surprise

for the New Horizons team.

The night before closest approach,

we made a point of sending home a handful of images in spectrum.

They were the highest resolution images

that had ever been obtained.

Pluto went from being just a small image in the distance...

Sort of like a jeweled Christmas ornament...

To all of a sudden

this massive world with unparalleled complexity.

But this is not the image

of Pluto the team came to see.

It's New Horizons' closest approach

that will truly reveal Pluto's secrets.

In less than an hour,

New Horizons will come within 8,000 miles of Pluto.

If the timing had been off,

that we had somehow just messed up

and instead of flying by Pluto at the prescribed time,

it was 1,000 seconds earlier or later,

we would have had everything pointed in the wrong place.

You don't want to wait two decades

and see a bunch of stars.

Okay, we have 25 seconds, folks.

T minus 25 seconds.

At 7:49 A.M., the team counts down

to the actual second New Horizons

makes its closest approach to Pluto.

Nine, eight, seven, six,

five, four, three, two, one.

Decades of work... They don't come down to one day.

They come down to one minute, to one second.

But no one really knows

if the probe survived the flyby

until it sends a confirmation signal back to mission control.

Radio signals traveling at light speed

are expected to arrive

at the APL mission operations center,

and we'll go live in the mission operation center

you can watch some of that activity.

At 9:00 P.M.,

the team gathers to learn New Horizons' fate.

We are searching for a frequency.

Stand by.

Waiting for the spacecraft to report back,

you could probably have cut the tension with a knife.

Everything's riding on this. And it's...

It's an incredibly high-stakes poker game.

Okay, we're in lock with carrier.

Stand by for telemetry.

You really don't know

if your spacecraft survived despite all the work

that you've done.

Stand by.

Yes!

Okay. Copy that.

We're in lock with telemetry with the spacecraft.

P.I., M.O.M. All clear to one.

We have a healthy spacecraft,

we've recorded data of the Pluto system,

and we're outbound for Pluto.

When we got that signal,

it was like a celebration

for the 10, 15 years of work that we'd put into that mission.

USA! We did it!

This has been beyond my wildest expectations in every regard.

I'm ecstatic.

It's returning beaifutul data,

and the Pluto system is just mind-blowing.

Within hours, New Horizons

begins to deliver its first images.

Our jaws were just dropping. It was incredible.

We'd transformed this little pixilated blob

into this real world.

What the team sees in the images...

Wow.

Is completely unexpected.

Even though logically I knew that it was a rocky,

icy planet,

I didn't expect it to look so similar

to features that we have on Earth.

I love this picture.

It's one that was made about 15 minutes

after closest approach of the very rugged terrains.

Many of these mountains are 10,000 feet tall.

The team has discovered mountains

of water ice the size of the rockies

on a planet smaller than our own moon.

You felt like you're there,

seeing the giant ice mountains and giant chmsas,

you know, much bigger than the Grand Canyon

in the United States.

We can auactlly see glacier flows.

It's molecular nitrogen ice.

It's almost like water ice is on the Earth,

and so it can float.

The discovery of water ice mountains

and nitrogen glaciers

leads Alan to one shocking conclusion.

Pluto is geologically alive after 4.5 billion years,

which upended many geophysical theories

that did predict

that small planets would cool off

and die early in their history

and just be a frozen relic of that time.

That tells us that our ideas

of how planetary engines work were wrong

and that we had to rethink them.

But one recently downloaded image further fuels

Pluto's mystery.

This is one of the most amazing finds we made at Pluto.

It's a giant ice volcano that was apparently active late

in the history of the solar system.

There are almost no craters on the flanks of this structure.

The big summit depression is the caldera of the volcano.

Nothing like this has been seen anywhere in the solar system

from Mars all the way to Pluto.

Sometimes I pinch myself that this is a real place

that we actually went and visited.

It looks like something out of science fiction.

And why Pluto should have these features

has got us baffled.

An active volcano would mean a source of heat

somewhere on the planet.

And now the New Horizons team

be lieves that heat could e warming an ocean of water

beneath the surface of Pluto.

It is a stunning discovery.

You have, you know, all of these other exotic things going on,

but it looks almost like tectonic activity.

And, you know, were is that coming from?

Why is Pluto still alive?

New images might solve the mystery.

The blue sky image... This is something

that was absolutely, totally unexpected.

The discovery of active geology on Pluto

has defied expectations of a frozen, dead world.

There were mountains of pure ice that were 10,000 feet high.

There were active glaciers of nitrogen and methane ice.

Nobody was expecting the drama and the beauty that we found.

But Pluto's biggest mystery may lie above the surface.

After we fly by Pluto and look back towards the Sun,

and we can actually see the atmosphere

and see this blue.

Pluto has blue skies.

Who would have thought? This is just amazing.

This blue atmosphere of nitrogen

should have dissipated into space billions of years ago.

Something is replenishing it, but what?

Could volcanic activity spew fresh nitrogen

from deep beneath the surface?

New images might soon solve the mystery.

We've got over a year's worth of data to still get down.

There's a lot of people that are losing a lot of sleep

these days trying to do this as fast as possible.

But by far the best images are still to come.

The search for answers

takes us from the edges of the solar system

to the edges of the universe itself.

March 4, 2016.

NASA releases an historic image,

one that many believed was impossible.

This red dot is an entire galaxy,

whose light took 13.4 billion years to reach us.

It is a photograph of our universe

in its infancy... A mere 3% of its current age.

All of a sudden now, you have a ringside seat

to watch the entire universe evolve

and change in front of you.

All of that is down to the Hubble space telescope.

What could this mysterious red galaxy reveal

about the origins of the cosmos?

That story begins

when the Hubble telescope is still on the drawing board.

Hubble was meant to solve a problem,

because people were trying to use ground-based telescopes

to measure how fast the expansion

of the universe was,

and that means the factor of uncertainty in the age

of the universe.

How and when did our universe begin?

Solving that mystery would be an historic success

at a time when the space program needs it most.

In 1986, the nation

is in mourning after the loss of seven crew members

aboard the space shuttle Challenger.

This is truly a national loss.

The members of the Challenger crew were pioneers.

We'll continue our quest in space.

The future doesn't belong to the faint-hearted.

It belongs to the brave.

They needed something to get back into the game.

And Hubble was sort of that big, shining star.

This was a big space telescope,

and we're gonna put this thing into orbit,

and it's going to look at black holes,

it's gonna figure out where the universe came from.

It's gonna revolutionize astronomy.

In charge of this daunting mission

is Charlie Pellerin.

The primary role of Hubble

was to fix things after Challenger,

to show we could still do hard things.

I kept reminding myself of John Kennedy when he said,

"we choose to go to the Moon

not because it's easy but because it's hard."

We chose to do Hubble because it was hard,

and it was damn hard.

Hubble will far surpass all ground-based telescopes

for one simple reason...

Earth's atmosphere.

If you look up at the night sky,

the stars are gonna appear keli they're twinkling.

But the star is not changing.

What's happening is that the same kind

of irregularities in the atmosphere

that you encounter when you get turbulence in an airplane,

it's all over the place.

W, the solution to that is put a telescope

above the atmosphere.

But unlike ground telescopes,

Hubble would be orbiting the Earth at an astonishing speed

of almost five miles per second.

And that's a problem.

Now, of course, the Hubble is this thing in space,

moving thousands and thousands of miles an hour in orbit,

which means its natural tendency

is that it's going to be tumbling end over end.

It's doing everything but holding still.

If you want to take a snapshot that's clear,

you know you have to hold your camera very steadily.

If you shake your camera, you get a fuzzy picture.

Same thing is true with Hubble.

The team must find a way

to stabilize Hubble perfectly.

The solution is a gyroscope.

Like a top, a gyroscope

maintains stability by spinning quickly on one axis.

The team will equip Hubble

with six of the most finely balanced gyroscopes

ever constructed, each with a wheel

spinning 320 times per second.

But even the tiniest imprecision

in the gyroscopes will smear Hubble's images.

So, if you asked me before the launch "is this all gonna work?"

And people did...

I would say, "of course it's gonna work,"

because there's no other answer.

What would you say? Would you say...

After you spent almost $2 billion in 15 years,

would you say, "hell, I don't know,"

or would you say, "let's hope so"?

What would you say? There's only one answer...

"of course it's gonna work."

Go for auto sequence start.

And liftoff of the space shuttle Discovery

with the Hubble space telescope...

Our window on the universe.

All go. We have a go for release,

and we're gonna be a minute late.

Okay, Charlie.

- Telescope's released. - Okay, thank you.

So, the telescope's up. Hubble's working.

It's deployed into space, and the shuttle comes home.

Feeling really pretty good right now.

The flight systems are all working extremely well.

Almost everything we agonized and worried about

has done a great job for us.

I think that, today, everything's going exactly

as we would have hoped.

We had an event about two months later

where we're gonna look at what's called "first light."

Charlie is with chief engineer gene Oliver

when the first images arrive.

And I said, "gene, waia t minute.

Wait a minute. That's a fuzzy spot."

Okay? He says, "oh, don't worry."

I said, "what do you mean don't worry?"

He said, "well, if it's out of focus",

we just re-drive the stepping motor in this direction

"until it's in perfect focus. So no big deal."

Charlie becomes convinced

all that's needed is a technical adjustment.

He leaves for a trip overseas.

When he returns, he calls his boss to check in.

So, he comes on the phone and says, "Charlie",

where are you?" I said, "I'm in the red carpet lounge

in St. Louis airport."

And he says to me, "what do you know

about spherical aberration?"

And I said, "well, all I know is that when people..."

Amateurs, typically...

Make a telescope mirror by hand and they do it sloppily,

"then the telescope's useless."

He said, "well, I'm glad you know that,"

because you launched Hubble space telescope

"with a spherical aberrated mirror."

I said, "did not." Heai sd, "did so."

This is two phd's, right?

He says, "go find the front page of any national newspaper"

and bring it back and read it to me."

So I come back, and above the fold,

"national disaster... Hubble launched with flawed mirror."

And he says, "now what do you say?"

I said, "you guys are good."

How did you get a fake newspaper

"into this very lounge that I'm landing in?"

The headline is no fake.

Charlie has launched Hubble with a fatal flaw

and not the one he had feared.

Yesterday, NASA admitted

that its multi-billion-dollar eye in the sky

has developed blurry vision.

We had failed in the most visible possible thing

we'd done in many, many years.

I'd have to say it was like a family member died.

It was like that. I mean, it really was.

May 1990...

Charlie Pellerin had just launched Hubble into space

with a fatal flaw.

Well, we're looking here at a star field

and these blurry stars, and there's no doubt

that we had a disaster on our hands.

Yesterday, NASA admitted

that its multi-billion-dollar eye in the sky

has developed blurry vision.

The observatory will not be sending back

the spectacular pictures that NASA had promised.

The reason is that the mirrors are not focusing light properly.

To achieve focus,

a telescope's mirror must be perfectly curved

so that its reflected light converges

at a single point.

After so much worrying

about Hubble's ability to stabilize itself,

Charlie's team made an amateur mistake.

Hubble uses a mirror.

It's 2 1/2 meters across... Eight feet.

And it focuses the light to a very, very specific focus.

And if it's off by even a little bit,

the light won't come to a focus.

The problem with Hubble is that it wasn't the right shape.

I believe that the edge of the mirror,

the whole error was like 1/50th of a human hair.

No human could ever look at that mirror

and suspect there's a problem.

We had so many safeguards.

And I look at this, and I just go, "my word."

Boy, we were in so much trouble and didn't knoitw ."

What a tragedy.

Basically, without some novel technical answer,

we're screwed.

NASA is embarrassed, while across the country,

Charlie and his team are mocked.

There was also much in the media.

Hubble was the butt of so many jokes.

People were saying, "well, how did we spend

almost $2 billion and come up with this?"

I tried to avoid the news as much as I could,

but it was impossible.

It was even in New York times, Washington post.

They had crying breaking out.

Astronomers are crying everywhere.

One of my most senior people is drunk at his desk.

When I realized what h hadappened,

I didn't believe my personal reputation was in danger.

I believed it was ruined.

I mean, it was gone.

I mean, for this level of failure,

arguably the biggest screw-up in the history of science,

and I was the leader of the team.

So, yeah, it was bad.

But Charlie is determined to find a solution.

I'm not waiting a minute

longer than I have to get this telescope fixed.

Didn't know how to do .It I had no idea

if it even was possible yet.

After months of searching,

his team thinks they might have an answer.

If the mirror was simply poorly ground

to a very sloppy weight, it'd be hopeless.

But the mirror was perfect, just ground

to the wrong prescription.

When we humans have vision problems,

we correct that problem by wearing eyeglasses,

which then are correcting the direction of the light

and making sure that it is focusing properly.

That is basically what the Hubble needed.

These glasses would come in the form

of a machine called C.O.S.T.A.R.

Contains five pairs

of small mirrors on motorized arms.

These mirrors correct the light beam entering the telescope.

We finally just sort of go, "my word."

We can fix this thing."

But with Hubble already in space,

this repair won't come easy.

Kathryn Thornton and her fellow astronauts

must risk their own safety to save Hubble from disaster.

A lot of things can go wrong when you're on a space walk,

but most people, when they leave the airlock,

are not so much afraid

that something's gonna happen to them,

they're afraid they're gonna mess up.

That's the biggest concern

is that our mission was so critical,

and it was critical that they be done right.

Hubble's science instruments are containeind four bays.

Kathryn must replace one instrument

called a high-speed photometer with C.O.S.T.A.R.

Once installed,

the corrective mirrors can deploy.

I mean, remember... This is a huge instrument

the size of a bus.

Nothing like that has ever been done before,

and it represents a huge number of technological challenges.

But Thornton is far from certain

that everything will go according to plan.

I would have bet money

that when we were putting these instruments in Hubble

we would have run into some problem

that we weren't expecting.

Okay. I'm gonna slip over.

You got another foot to keep coming up.

Is a great big silver box

the size of a phone booth.

And I would have bet

that things wouldn't fit, that we're gonna slide

this thing in and it's gonna get halfway in

and it's gonna go "ka-thunk" and hit something.

And as bad as it was, we could always make it worse.

We could have killed it. We could have killed it.

This is opening the door for C.O.S.T.A.R.

I'm on the end of the mechanical arm,

and I can recognize that from this picture

because I can see the broken red stripes

around my thighs there.

I haven't seen some of this in a long time.

This is nice. I like this.

We had a lot of eyes watching us.

We had everybody on the ground watching,

we had everybody in the crew module watching us.

You know, "don't hurt it. Don't hurt it."

Don't hurt it. And it's all up to you.

"Don't screw this up."

Is a pretty big instrument.

It weighs several hundred pounds,

maybe 700 pounds on Earth,

and I can move it with just my fingertips.

As C.O.S.T.A.R. Slides into place,

Thornton can only hope that everything will fit.

And it just slid right in.

Could feel it hit a stop. That was a bit of a relief.

The nightmare I hadid dn't happen.

But they couldn't calibrate it until after we were long gone.

And so we had no idea

that our mission was successful even after we landed.

All anyone can do is wait for the pictures.

11 days later, the calibrations are complete.

You know, this is what was happening

in December of 1993...

Everybody gathering around the monitors

and looking at the first images taken by Hubble space telescope.

- Whoa! - Hey, hey, hey!

And they were gorgeous.

- Oh! - We did it!

- Wait, wait, wait, wait. - No, no, no.

I'm sitting there with tears running down my face

looking at this stuff, and everybody's spellbound.

I had no clue that the images

would be as powerful as they are.

I never imagined something like this.

This is... this is astounding.

That's got to be astounding to anybody.

But these are more than beautiful images.

Each pixel helps unlock another scientific mystery.

'Cause people were trying to use ground-based telescopes

to measure the expansion of the universe,

and that means uncertainty in the age of the universe.

But by looking deeper and deeper,

it's looking farther and farther back in time.

And it's measuring the expansion of the universe,

so we can tell precisely

when the universe formed, you know,

13.7 billion years ago.

Hubble has solved, you know, one of the biggest mysteries

in astronomy and in science.

With each image, the discoveries keep coming.

They pointed Hubble at a place

in the sky where there was nothing,

and there are like 1,500 galaxies in that photo.

1,500 galaxies.

You know, our milky way is just one tiny, little galaxy.

We now know that there are more stars in the universe

than grains of sand on all the beaches

in the world.

But Hubble is also a time machine.

You see, there's this wonderful look-back effect,

where the farther out in space you look,

it took ghlit a long time to get to you.

And now you look at thesime ages,

and you effectively look back almost to the beginning of time,

the beginning of the universe, wi th Hubble.

This new image from march 2016

is the furthest look back in time yet.

The light from this young galaxy dates to just 400 million years

after the big bang.

It is surprisingly bright,

which means that galaxies were growing much faster

and much earlier than we ever knew.

25 years after launch, Hubble continues to amaze.

The idea that someone could be interviewing me

and putting these images

up in front of me and having me comment on them

and telling me that we're in our 25th year

of successful science operations,

that's a mind-blower.

In NASA, I think Hubble's only second to the Moon landing.

I mean, it's that big.

Coming up, a team of scientists searches

for the origins of life on an asteroid

that can also bring us death.

Could cause a tremendous amount of damage in the local area

where it hit.

As we look farther into the universe

than ever before,

we may be looking deeper inside ourselves.

One of the most surprising facts

about our relationship with the larger solar system

we live in is that the organics in our body

were most likely brought here to Earth

on comets and asteroids.

Rich in molecules called nucleobases,

the same molecules that make up our DNA,

asteroids could be the key

to unlocking the mystery of life on Earth.

And maybe the very origin of your body, of the chemistry

that you're using to watch TV right now,

came from the asteroids.

One asteroid is especially intriguing.

Its name... Bennu.

In the case of Bennu,

it's about half a kilometer across rock.

Bennu itself is an exciting object.

It's a carbonaceous asteroid.

Carbonaceous means

that it contains the element carbon,

which, as we all know, are associated with life.

Bashar Rizk is a scientist

at the university of Arizona.

But it's not just the possibilities of life

that makes Bennu interesting to Bashar.

It's also the possibility of death.

Bennu is a class of asteroids

that share the same region of space as the Earth

as they move around the Sun.

Every six aryes,

it's in the same general region as the Earth.

That increases the opportunity

that it would actually hit the Earth and cause damage.

To understand

whether Bennu truly poses a risk to Earth, we need to see it.

In the mountains outside Tucson, Arizona,

Eric Christensen searches the skies above Earth

for asteroids and comets.

This object that's circl iedn red

here in the middle, it looks like a faint star,

but it just happens to be the asteroid Bennu.

Or the Catalina sky survey is our first line of defense

against asteroid impacts.

Asteroid impacts are really a fact of life.

They always happen, they have always happened,

they will always continue to happen.

We will point our telescope at a particular area of the sky,

and we will build up over time, essentially,

a very low resolution movie.

We can compare the images

and identify stars that are stationary.

And then anything that is not stationary

is a potential moving object.

When astronomers discovered Bennu,

they quickly realizethd at of all the near-Earth objects

in their sights, this asteroid has one of the highest chances

of impacting Earth.

Bennu had come near the Earth near enough

that we could get radar reflection off of it.

Therefore, we know something about its shape.

To fully understand where Bennu is going,

Peter and Bashar need more than just fuzzy radar imesag.

So in September 2016,

they will launch a spacecraft called Osiris-Rex.

After two years of traveling through space,

it will intercept the asteroid.

Once there, its mission is two-fold.

Osiris-Rex will collect a sample of the asteroid

to return to Earth,

and it will photograph the entire surface

in extreme resolution,

taking pictures down to the size of a pebble.

Our cameras will go and try to characterize

the asteroid's environment.

We're gonna image this object to a higher degree

of resolution over a larger piece

of its terrain than has ever been done before.

Mapping Bennu with these cameras is essential,

because we'll understand the gravity of this object

to a much more precise degree.

Predicting where this object

will be 100 years into the future

is very important, because this is one

of the potentially most hazardous objects

in the solar system for the Earth.

To precisely determine Bennu's future orbit,

scientists need to know the asteroid's exact size

and shape.

That's because of a phenomenon known as the Yarkovsky effect.

Any object in the solar system

experiences the Yarkovsky effect.

Now, what is it?

Well, it's a thermal asymmetry

that happens because of the rotation of an object.

As the Sun's energy strikes Bennu,

it gradually changes the asteroid's orbit.

Things have had a chance to heat up.

Now, when something is hot,

it tends to emit photons, thermal ones.

Photons carry momentum.

So, what this is doing is acting like a little bit

of a thrust in this direction.

If I thrust that way,

I'm kind of increasing the energy of the orbit

and moving it out from the Sun a little bit.

The high resolution images

from Osiris-Rex will tell the team exactly

how the Yarkovsky effect is influencing Bennu's path.

If an object the size of Bennu struck the Earth,

there would be a regional catastrophe,

perhaps taking out as much as a state or several states.

It could cause a lot of damage and the loss of a lot of life.

Space is all about exploration,

and it's something we humans seem to kind of be wired with.

History's shown that you've got two choices...

You could either keep marching ahead

or you could fall behind

and end up in the dustbin of history.

Standing still is not an option.

Revealing the deepest secrets from space

can inspire wonder,

but they can also incite fear.

This grainy image shows an asteroid called Bennu,

and it may be on a collision course with Earth.

Odds of Bennu hitting the Earth

are less than 1 in 2,000.

That's still considered high for this class of object.

Typical odds would hopefully be lower than one in million.

Bennu is smaller than the asteroid

that killed the dinosaurs,

but it could cause a tremendous amount

of damage in the local area where it hits.

For instance, it could really damage something

the size of a large city.

Or if it hit just off shore, it could create a tidal wave.

In September 2016,

Bashar and Peter will send a probe

to photograph Bennu in detail

and reveal its secrets.

But a mission like this is fraught with potential pitfalls.

In August 2014, a spacecraft

called Rosetta arrived at another small body,

a comet caught in Jupiter's gravity.

Three months later, the Rosetta team

attempted to land a probe called Philae

on the comet's surface, and it ended in disaster.

Philae was equipped with a couple of harpoons

so that when it made its landing,

they would shoot out and ideally try to moor it there.

Except that, apparently,

the harpoons did not fire when Philae landed.

So, because of that, Philae hit the surface and bounced.

And it bounced several times because of the comet's rotation

and the lander's own velocity.

And it wound up coming down in an area of the comet

that we didn't have good maps for.

And so basically, the lander was lost.

The team is determined to see their mission succeed.

That's because there is more to learn from Bennu

than whether or not it will collide with Earth.

It could unlock the origins of life on our planet.

the Earth formed when objects slammed together.

But later on, as it cooled

and water became a large part of the surface composition,

then it was possible for future impacts

with smaller objects

to actually bring in organic materials

that could survive on the surface.

That's how many people think organics came to the Earth...

Through those impacts from asteroids.

When we get a sample of Bennu back into our laboratories,

we're gonna be looking at material that formed

in the initial phases

of the formation of the solar system.

If we could someday prove

that the building blocks of life on Earth

actually came from space and not from our own planet,

it would turn everything we understood about the origin

of life on its head.

Osiris-Rex will not attempt a landing like Philae.

Instead, it will get a sample of the asteroid

with a revolutionary new system called

T.A.G.S.A.M.

"Tag" stands for "touch and go,"

and "Sam" is "sample acquisition maneuvers."

So T.A.G.S.A.M. Is the actual act

of reaching out,

touching the surface of the asteroid

and gathering the sample, then pulling away.

Once samples from Bennu arre ivback on Earth,

we can test them for the kinds of organic materials

that could have seeded Earth four billion years ago.

But to successfully retrieve the sample,

the cameras must function perfectly.

The cameras are one of the critical experiments

on this mission because, as we get closer,

it can refocus and actually become more like a microopsce,

and it can detect grains

that are just a few millimeters across.

So when we get to our sample site,

we want to get the highest resolution possible.

With only months to go until liftoff,

the clock is ticking to get Osiris-Rex right.

We'll be launching in September of 2016.

So we have a schedule pressure here

that I think does take its toll on the team.

There are a number of things

that we're trying out for the first time,

and that keeps people up at night at NASA.

Should the mission fail,

NASA will need another way to reach Bennu.

Scientist Ben hockman cread tea backup plan,

and to test it, he's hitting the beach.

I think most people assume

asteroids are just big rocks in space

when in fact they have very interesting surface geology.

We've found through recent missions

that there can be a wide variety of different surface features.

With its mix of sand and rocks,

this beach mimics terrain

that NASA has observed on comets and asteroids.

It is the perfect place

to test Ben's rover nicknamed dgheehog.

Hedgehog is a whole new class of rovers,

very different from the previous rovers

that we've sent to the Moon and Mars.

We have seen that the topology of asteroids can be very uneven,

so there's potential

that a rover could fall into a pit or a crater

and be unable to escape.

All right. Hopefullthy is works.

It may not look like much,

but on an asteroid,

where gravity is a tiny fraction of the Earth's,

this same hop would propel Hedgehog

far across the surface.

It uses three internal flywheels to build up momentum internally.

And by doing that, it can hop and tumble across the surface.

These spinning flywheels build up momentum,

and when Ben applies the brakes,

he transfers that momentum into motion.

Think about it like you're driving your bike

and you come to an obstacle and you hit your front brakes.

You have a lot of moment about your front wheel,

so you have a tendency to want to flip over your front wheel.

The same is true for Hedgehog,

but we do that to our advantage to hop in a controlled way.

But to see how Hedgehog will work

in a near-zero-g environment,

Ben must head to the lab at Stanford university.

So, this contraption is called a microgravity testbed.

The microgravity testbed allows us to emulate

what the rover might do in actual microgravity conditions.

The bed shows Ben

how Hedgehog will behave on an asteroid like Bennu.

At those scales, gravity

is about 1,000 or 10,000 times lower than that of Earth.

So on an asteroid,

a human would weigh as much as a paperclip.

One of the key advantages of Hedgehog

is that there's no right way up.

In other words, it can land on any side

and be just as capable of moving

as if it were to land on its fit, so to say.

And Hedgehog holds one other advantage.

Because Hedgehog is so compact and cheap,

you could store potentially many of them in a spacecraft

that you send to a small body.

So you could imagine an myar

of Hedgehogs hopping around the surface,

exploring the physical properties of an asteroid.

For now, Hedgehog is only a prototype.

So it will be up to Osiris-Rex

to unlock the secrets of Bennu.

The answers won't come until late 2018,

when Osiris-Rex and its cameras finally reach the asteroid.

I think that the images of Bennu

are going to be revelatory.

Waiting for those images

to come back in 2018 and 2019 will be...

The only thing I can compare it to

would be waiting for the births of my two children,

because it's something very important to you

and you're not quite sure of the outcome.

Until then, scientists can only wonder if Bennu

will change our understanding of life on Earth.

How did all that get going?

Did it start it here,

or was it brought here from outside?

We don't really know the answer to that.

We're gonna go find out.

If the building blocks of life did come on an asteroid,

perhaps Earth wasn't the only planet where they landed.

Today, a team of scientists

is driving a rover millions of miles away to see

if life could have thrived on another world.

You get a flat tire on your car, no big deal.

You call AAA.

You get a flat tire on the rover,

that's the end of the mission.

For years,

a satellite called the Mars reconnaissance orbiter

has been photographing dark streaks

on the slopes of a crater...

Mysterious lines

that appear to change with the seasons.

On September 28, 2015,

NASA scientists announced their groundbreaking conclusion.

What we're going to announce today

is that Mars is not the dry, arid planet

that we thought of in the past.

Today, we're going to announce

that under certain circumstances,

liquid water has been found on Mars.

Scientists have never found liquid water on a surface

anywhere beyond Earth.

The discovery is historic.

Life as we know it on Earth needs liquid water to survive,

so that's kind of the key first thing that we need.

We also need organic materials.

So those are some basic elements like carbon and hydrogen

and oxygen.

In 2012, a rover

called Curiosity landed in an ancient martian lake bed

known as Gale crater.

A roving chemistry lab, Curiosity drilled into the soil

in search of organic molecules.

One of the last pieces of the puzzle with Mars

is that we'd never been able to detect the presence

of organic molecules.

And Curiosity put that puzzle piece in.

We know that there are organics in the soil.

We also discovered... And this is really important...

We found an environment that wasn't very acidic.

And that was really our first discovery

of a habitable environment on Mars

where we think life could have existed.

We have found evidence of water and organics.

But were they both plentiful on Mars for billions of years,

perhaps even long enough for life to take root?

Mount Sharp,

the three-mile-high peak at the heart of Gale crater,

may hold the answer.

It is a time machine.

The higher up the slope you go,

the further back

you travel in Mars's geological history.

We really were looking to Mount Sharp

to tell us the record

of environmental change through Mars's history.

We think that there's a possibility that,

as you go up through the layers of Mount Sharp,

we may be exploring different habitable environments.

And so what we're interested in finding out

is how does the habitability as a whole change through time?

Today, Curiosity is entering a new phase of exploration

by climbing Mount Sharp.

Along the way, it will alanyze the soil,

piecing together three billion years

of martian history.

But for rover driver Matthew heverly,

the path ahead is fraught with danger.

We're always pushing the limits of this vehicle.

I mean, the rover's amazing. It can handle so much.

But as we go to Mount Sharp,

we've got some pretty gnarly terrain

to head over.

Here we go.

To find out just what kind

of terrain Curiosity can handle,

Matthew and Katie take a rover out for a spin.

So, we built three rovers.

We sent one off to Mars, we built an exact copy

that we keep here on Earth

for testing software and cameras,

and then we built another one, scarecrow,

because we have to adjust for gravity.

Mars's gravity is 3/8 that of Earth's.

So Curiosity's 2,000 pounds become about 750 on Mars.

Scarecrow rover's stripped down,

but it weighs on Earth what Curiosity weighs on Mars.

So it's got the right ground pressure.

It's got the right, you know... As we're going up a hill,

it's carrying the right amount of weight up that hill.

So we can test in the Mars yard

how steep a slope can we climb up.

Satellite photos reveal that the most direct path

up Mount Sharp would take Curiosity through sand dunes.

So Matthew and Katie decide to see

just how much sand the rover can take.

Sand is scary for us

because we understand what's going on,

but we get constantly surprised.

What angle do you have there? - We're at like 16 1/2.

We would not do this much slip in operations

unless we were very sure we could get out.

Yeah.

And then it just gets harder to extract yourself.

What we're learning is that the sand dunes

are really just too great of a challenge

for the rover to handle.

The rover actually does a better job

with the steep, rocky slopes.

The team chooses a path around the dunes.

And curiosity continues on its journey

up the slope of Mount Sharp.

Will Mars prove to be a planet where life once thrived?

Only time will tell.

Coming up,

these mysterious images take the search for life

to a totally unexpected place...

A tiny moon called Enceladus.

This is the single most important and interesting place

for astrobiology in our solar system.

October 28, 2015.

The Cassini probe captures one of its final images

of a mysterious moon orbiting Saturn.

Its name... Enceladus.

Its diameter is just 310 miles...

Less than 15% of our own moon.

But these photos reveal what appear to be

volcanic geysers spewing from its surface.

Scientists are trained not to jump to conclusions,

so we weren't gonna say "definitely",

we've found something."

We thought, you know,

"Toto, we're not in Kansas anymore."

This is something really, really outstanding

and something very significant.

Why do these plumes exist?

What is inside them?

To me, it eclipses everything else

we know about the other worlds in the solar system.

This is the single most important and interesting place

in our solar system beyond the Earth.

Could this tiny ball of ice

actually contain the ingredients necessary for life?

In 1977, NASA launches two spacecraft

on a 12-year journey

to the outer edge of the solar system.

The Voyager probes send back the first detailed images

and data of the gas giants beyond the asteroid belt.

But one planet captures the heart of Carolyn Porco.

I was a graduate student when Voyager flew by Saturn.

I did my thesis on Saturn's rings.

And it's, you know, like your first love,

where it's the jolt

that we scientists get is finding something new

that nobody else knows about.

And all that happened for me at Saturn.

But one moon seems to hold

more mysteries than the others.

Covered in a thick orange atmosphere,

its name is Titan.

It was Titan, completely enshrouded in haze,

and we didn't know when we got there with Voyager

whether or not we'd be able to see down to the surface

with our cameras, and it turned out we couldn't.

Unable to see past the atmosphere,

Voyager cannot solve the mystery of what lies beneath.

Titan was an object of immense interest.

This was the place that we need to go back to.

So when NASA put out this announcement of opportunity

saying, you know, "come apply to be involved

"in our next adventures at Saturn," I applied.

And I'm so grateful that I had the chutzpah

to think

"I'm not just gonna be a member of the imaging team,

I'm gonna lead it."

In 1990, Carolyn's dream comes true.

NASA places her in charge of the imaging team for Cassini.

And this mission will be different.

Voyager, mind you, was a reconnaissance mission.

It was just a flyby.

And the whole purpose is just to see

wh'sat there in the brief period of time

that you're allowed.

But Cassini will enter Saturn's system

and stay there for years,

imaging the planet and its moons

with high-powered cameras and scientific instruments.

Three, two, one.

And liftoff of the Cassini spacecraft

on a billion-mile trek to Saturn.

In July 2004, Cassini arrives at Saturn.

And right away, it delivers on its promise,

taking the most detailed images ever

of the ringed planet and its moons.

I had been thinking about Voyager imagery,

and then I walk into my lab and I see this picture,

and it's incredibly detailed.

And that's when I thought, "oh, my god."

This is gonna be just spectacular.

This is gonna be a wondrous thing,

"what we're gonna be doing at Saturn."

The Cassini mission brought us a wealth

of scientific discoveries about Saturn.

For example, it helped discover four new moons.

Cassini revealed entirely new detail

about Saturn's amazing rings

and the way that they're moving around the planet.

But for astrobiologist Chris McKay,

the real star of the show is Titan.

The reason Titan was so interesting

for astrobiology was that it is so rich in organics.

There's an organic haze in the atmosphere.

We thought that there would be organic liquids on the surface.

Organics are the carbon-based molecules needed f lorife.

Could organic liquids

indicate some form of life on the surface of Titan?

Carolyn and the team

have equipped Cassini to do what Voyager could not...

See beneath the haze.

And it will happen by sending a probe called Huygens

right down to the surface.

So Huygens was designed to drop from the Cassini probe

and deenscd through the atmosphere

and make a soft landing on Titan,

sending back information the whole way

about what Titan

was actually like and finally giving us a chance

to peer through these murky clouds

on the surface.

On January 14, 2005, Huygens makes its descent.

When the Huygens probe descended through Titan's atmosphere

on a parachute, it was taking images of the surface.

We didn't know what to expect.

But it showed what look like shorelines.

When we got pictures of the surface,

it was very clear

that there had been liquid of some kind on the surface

for a long time.

But Titan's surface

is nearly minus 200 degrees Celsius,

so that liquid cannot be water.

So Titan has clouds, it has rain,

it has rivers, it has seas.

But it's methane and ethane.

And the real question for astrobiology is,

is there some sort of chemistry that could make life

that could live in this kind of liquid?

For life to exist on Titan,

it would have to be so alien

that it survived on methane instead of water.

Although Chris McKay is hopeful, it's a long shot.

But Titan is not the only moon orbiting Saturn.

Enceladus was a moon

that we knew from Voyager was unique.

It was the whitest object in the solar system.

It was the brightest object in the solar system.

It was associated with the very big ring

of very, very fine smoke-sized particles

that had been discovered around Saturn in the 1960s.

Enceladus was the place that we were just pulezzd about.

And other than Titan, Enceladus was the Moon

that, on Cassini,

hwead planned to have the greatest number of flybys.

Carolyn Porco turns her attention towards Enceladus.

And once Cassini arrives,

a single photograph transforms the entire mission.

I was focused on Titan, but then my world changed.

For me, it was really an "oh, my god" moment.

In February 2005,

the Cassini space probe

makes a shocking discovery

on Saturn's icy moon, Enceladus.

Our first observation turned out

to have something coming off the south pole,

and it was clear.

Everybody just went all abuzz with this. Like, "wow!"

There's something coming off the south pole!"

Everybody was getting excited.

Scientists knew that the Moons of Saturn were cold.

And then they suddenly see these images of Enceladus,

and they noticed a kind of activity

that you don't expect from some sort

of cold, dead moon.

The image shows a plume of material streaming miles

above Enceladus.

The Cassini team suspects that it's water somehow ejected

by a powerful amount of heat and energy.

Carolyn Porco immediately contacts Chris McKay

with the news.

Carolyn calls me up. I'm in a meeting.

But I know if it's Carolyn, it's an importt anmessage.

So I ducked out of the meeting,

and I listened to the phone call, and I was stunned.

And that's when I learned about all the interesting stuff

coming back from Enceladus,

evidence of energy coming from a subsurface ice environment.

My world changed.

The reason why this discovery mattered so much

is that it meant that there might be an enormous amount

of really interesting chemistry going on there...

The kind of chemistry that might be similar

to what we saw in the early days of the Earth,

maybe replicating the kinds

of conditions that might give rise to life.

Our first thought was "we got to get a closer look.

Okay, we've got to figure this thing out."

A few months later,

the probe makes another flyby of Enceladus.

And this time, there's no mistaking the power hiding

underneath the icy surface of this moon.

And that's when we really had our,

you know, our socks blown off,

because that's the picture

where you see about a dozen narrow jets

coming off the south pole.

We found out that heat was coming

from these four fractures.

But what is producing something so extreme?

Scientists believe the gravitational forces

of Saturn are tugging on Enceladus,

creating friction inside the moon.

The evidence indicates Enceladus has massive amounts of water

and a powerful source of energy...

Two key ingredients in the search for life.

And the next step is, can we say something from the molecules

we see about the conditions

of what's going on this subsurface?

Can we say anything about the presence of biology?

Can we see anything

that could be consistent with biology?

The team looks to find signs of organic material

in the plumes.

And what Cassini finds provides even me orevidence

that the building blocks of life

may be brewing underneath the icy surface.

We have found that the particles

in the plume close to the surface were salty

and they had a salinity comparable

to the Earth's oceans.

And that said that this body of water

had to be under the ice shell

and in contact with a core,

in contact with a rocky core.

It could be an environment

similar to hydrothermal vents

at the bottom of Earth's oceans...

A place where life exists.

So, all of this put together said that we had a zone

that could possibly sustain life, okay?

It had the basic irengdients.

It doesn't mean it has the secondary

and tertiary ingredients,

but could it possible be a place where, you know,

if biological activity is not taking place now,

it might be well on its way to taking place.

Over the next veseral years,

Cassini continues to gather data and photos

from Enceladus and its plumes.

But in December 2015,

after 10 years of flybys,

Cassini approaches Enceladus for the last time.

Carolyn and Chris are among the first people

to see the final images.

This is the last flyby of Enceladus by Cassini.

These are the last close-ups.

That's right. Are you strapped in?

He re we go.

Look. Oh, my god. What...

Oh, those are just craters, but look at them.

It's incredible, isn't it?

Really nice.

Wow, I wasn't expecting that.

We're gonna be working with this now divine set for a long time.

Oh, very long time.

I mean, Cassini's been so incredibly rich.

I bet we'll be working with Cassini data for 50 years.

But this final pass by Cassini

doesn't study the plumes on Enceladus.

If scientists are going to continue

looking for signs of life,

a new probe will have to go back,

because in September 2017,

Cassini will end its mission and plunge

into the atmosphere of Saturn.

For scientists who are looking for possibilities

of life in the outer solar system,

seeing these jets on Enceladus,

this is winning the world series

and the super bowl all rolled into one.

This is the best possible discovery they could make.

That's why Dr. Porco and her team

are determined to return with a new spacecraft.

We're not sure that there's life there.

We just have strong indications that there is at least

an environment there that could support life,

and maybe even an environment

where life might veha originated.

So, the thing

that many of us want to do is we want to go back,

and if at all possible,

eventually bring back a sample to Earth.

To me, it eclipses everything else

we know about the other worlds in the solar system.

This is the single most important and interesting place

for astrobiology in our solar system

beyond the Earth.

Could you tell I'm enthusiastic about it?

Coming up,

there are many unexpected dangers

to exploring the universe.

But it turns out one of the most likely threats

we've created ourselves.

Radar detected that something was moving very, very fast

in the direction of the space station

and that a collision was a very real possibility.

Our exploration of the universe

has opened the door to a world of new discoveries.

Hubble has revealed

that the universe is expanding faster than anyone realized.

Cassini has opened new possibilities

for life beyond Earth.

But the most important discoveries

could be in our own backyard.

The thing about the international space station

is that it's in about a 200-mile above-the-Earth orbit,

and so there's this wonderful detail.

Pictures from the I.S.S. To me

often seem like abstract paintings.

There are details of river deltas

or sand dunes

or forests,

and they're works of art.

They're so beautiful that I have to stop

and look at these and just soak them in.

For six months, astronaut Ron Garan

lived and worked on the international space station,

and he saw our world in a way few people can imagine.

The Caribbean is like a glowing jewel.

The himalayas, the middle east...

There's many, many really interesting,

beautiful places from space.

The space station gives us the ability

to explore our home planet in a way we never could.

But that god's eye view is getting dangerous.

We have a somewhat risky environment

that we've created because we are surrounded...

Our planet is surrounded... By this cloud of space debris.

Three, two, one, zero.

And liftoff!

For almost 60 years,

we've launched rockets and spacecraft

into Earth's orbit.

But now thousands of objects,

from tiny screws and bolts to dead satellites,

encircle the Earth,

transforming the space above us into a junkyard.

It seems kind of comical the idea

that someday the Earth might actually be surrounded

by some ring of space garbage,

kind of a like a less-nice version of Saturn,

but it's a real possibility.

Now the international space station

is in the cross hairs.

The international space station

has already been hit by little bits

of debris on a number of occasions,

and there are no guarantees that other substantial things

might not hit it again in the future.

It's the job of the military to monitor the thousands

of pieces of debris orbiting the Earth.

The men and women at Vandenberg air force base

in California are keeping their eyes

on the skies 24 hours a day.

So, currently we monitor

and track approximately 23,000 objects in space.

Among those is about 1,300 active payloads or satellites,

and the rest being space debris from prior launches

or prior collisions.

Everyone on Earth should care

about what's going on with space objects

and space debris

because we're so reliant nowadays upon technology that,

if something were to happen to a satellite, it's going

to severely degrade our ability to do certain things,

whether it be atm withdrawals, GPS,

or anything.

It's critical that we track space debris

because it poses a risk to all active payloads,

including the international space station.

Some of this debris we track up to c10entimeters.

Even a piece of debris

the size of a small screw could destroy the space station.

If you can think of a two-centimeter ball bearing

up in space, it's traveling at 17,000 miles per hour.

That force is equivalent to a Jeep wrangler

traveling at 70 miles per hour.

So as the object's size increases,

the impact and the force behind that collision

could be astronomically larger.

In June 2011, Ron Garan

found himself facing that danger firsthand.

I was maybe four months or so into the mission,

and we got a call from mission control

that a piece of space debris

was gonna pass a lot closer than people wanted.

If we know about it soon enough,

we will change the orbit of the space station.

We can boost it up higher or lower

and change it so that we avoid that object.

But for whatever reason, this one caught us by surprise

and we did not have enough time

for us to be able to move the orbit of the space station.

With the astronauts

staring down the threat of a collision,

they're faced with only one choice...

Abandon ship.

The international space station has several different ways

of trying to deal with potential collisions,

but the last-ditch defense are the two soyuz space capsules,

because those are basically lifeboats.

Ron and the crew race to the soyuz capsules.

Now the only thing they can do is brace for impact.

And then it was just a waiting game after that.

We didn't know if it was gonna hit it or not.

In June 2011,

the crew of the international space station learns

their lives are in imminent danger.

Space debris is heading towards them.

Nbc Jeff Rossen, watching all of this.

Jeff, good morning to you.

Space junk was on a collision course

with the international space station,

spotted so late there was no time

to move out of the way.

Instead, the six astronauts

got the order from mission control.

If all else fails, the astronauts on board

the space station can climb into those soyuz space capsules

and wait to see whether a collision

actually takes place.

If it does, they can, in a few seconds,

detach from whatever's left of the space station

and then immediately try to return to Earth.

Mission control orders

the astronauts to the soyuz lifeboats.

It's only the second time

a crew has been told to potentially abandon ship.

Once we got all the hatches closed

and we were all buttoned up in our soyuz spacecraft,

there really was nothing to do but wait.

We discussed, "okay, if things get really bad",

this is what we're gonna do. We're gonna undock."

You know, we started to talk about that.

And then it was just a waiting game after that.

But we didn't know if it was gonna hit it or not.

Finally, after 15 minutes,

word arrives from mission control.

When the object passed the space station,

we got a call from mission control

that, you know, it was all clear.

And it turned out that this object

passed within a football field of the space station,

and relative velocity was eight miles per second.

So a fairly large object traveling that fast,

it probably would have destroyed the space station had it hit.

But with thousands of objects orbiting the planet,

the next time, they might not be so lucky.

There is evidence of hits on the space station,

and, you know, a little piece the size

of a grain of sand could really make a bad day.

It's something that should be a major concern

if we're gonna continue to use the environment of space

for the things that we want to use it for.

Exploring Earth in the 21st century

means capturing it from above.

But space debris is not the only threat

to this unique perspective.

the Sun seems to be always there and unchanging.

It's just this bright ball of light in the sky.

But in fact, it's changing all the time.

And that affects us here on Earth

because we are bombarded by radiation from the Sun,

both in the form of light and subatomic particles.

the Earth's atmosphere

is a protective shield for anyone on the ground.

But in space, there's no escape from the power of the Sun.

Solar flares and other kinds of violent eruptions

from the Sun are very, very dangerous

for anybody who's in space.

The amount of radiation

that suddenly is pouring off of the Sun

at that point jumps way up.

And we can try to create certain kinds of very shielded areas

that the astronauts can hide in,

but even those can only offer

very inadequate protection

against the level of radiation

that the Sun can suddenly release at those times.

An extremely powerful solar storm

could send the crew looking for cover.

What we would do is we would find a place

on the space station that offers the most protection.

Water turns out to be a fairly good insulator

of radiation.

And we do have bags of water on the space station.

We'd probably huddle some bags of water into a location

and get behind that as best we could.

But in spite of that danger,

the same powerful burst of energy

also gives the astronauts

on the space station front-row seats

to the greatest light show imaginable.

The auroras are just incredible.

And there were times on my mission

where we flew so close to the auroras

that you could reach out and touch them.

I mean, they were going right by the windows.

It was absolutely incredible.

The pictures really don't do them justice.

They really do dance.

But what you're seeing, really,

is the aftereffect of a tremendously energetic

and dangerous solar storm.

These subatomic particles

screaming across the solar system

at just under the speed of light

are getting swept up by the Earth's magnetic field

and funneled down into our atmosphere.

It's humbling and amazing.

From discoveries at the edge

of the solar system and beyond...

to mysterious asteroids hurdling through the cosmos

and the search for life in our own backyard,

images have transformed our undersndtaing

of the universe.

Everyone knows the cliche

"a picture is worth 1,000 words."

But to me, being a scientist,

you have to find a way to turn cold numbers,

just data,

into something that emotionally resonates with people.

We are trained to be very, very logical,

but all of us, really, are just like everybody else.

We're emotional and, you know,

we get excited about a beautiful scene

and can, you know,

just spend hours looking at something

and imagining what it would be like if we were there.

And these images are the result

of cutting-edge missions

driven by the explorers willing to put everything on the line

to capture space's deepest secrets.

These days, I think we've seen

that there's a whole new team of heroes.

These teams of scientists and engineers,

they're the ones inventing these craft.

They're the ones devising these missions.

They're the ones making sure they come off without a hitch.

They're the realer hoes now.