Original subtitles

- [Voiceover] The moon, our closest celestial companion.

Our indispensable dance partner through the cosmos.

Lighting our night sky and gently tugging at our shores.

Few have walked on her surface,

but her allure remains strong.

Once again, we are glancing her way with renewed interest

and with a view to returning very soon.

(exciting orchestral music)

- [Voiceover] Huston, Tranquility Base here.

The eagle has landed.

- [Voiceover] Roger ...

- [Cathy] When I was a little girl and

people were always asking me,

"What do you want to be when you grow up?"

And I used to always go, "I want to work up there."

As an engineer

you dream of a job like this

where you get to follow in the footsteps

of some of your childhood heroes.

And, of course, for me the Apollo mission,

seeing these folks on TV step on the moon

and work for NASA.

As an engineer it's just a dream to be able to say,

"You know, I want to do that too."

And here I am.

- [Voiceover] Only a dozen Americans

have kicked the dirt on the lunar surface.

It was a bold and dangerous engineering achievement

driven by a political agenda.

- The Apollo program was important

because it showed that we could leave our home planet

and visit an object like the moon.

However, what we want to do next,

is learn how to live and work off of our home planet

on another planetary surface, like the moon.

By developing this capability,

we'll be able to know how to

go throughout the inner solar system,

which has many important destinations

both for science understanding,

and also may have economic importance

for not only our generation, but for future generations.

- [Voiceover] The Soviet Union and the US

had peppered the lunar surface

with soft and hard landing spacecraft.

The Soviets' Lunar 24 was the last of that program,

returning soil samples that contained traces of water.

Much of science and technology has advanced since the 1970s.

The mechanism of world politics has evolved,

new partnerships have formed,

new players are looking skyward, and more recently,

private enterprise has taken up the challenge.

With the faintest of inklings that there may be

usable water on the moon,

a forensic focus has turned to the southern polar region.

Scientific programs in the 90s refocused on the moon.

Japan was the first to revive lunar research

and only the third nation to achieve lunar orbit

with Hiten on a dust collecting mission.

The US followed with Clementine,

a joint NASA-military project.

It completed a mapping survey of the lunar surface

along with gravitational data

and evidential proof of possible water ice

hidden in a south polar crater in permanent darkness.

Four years later a lunar prospector mapped

lunar resources, gravity, and magnetic fields.

It was also impacted into the southern region of the surface

to elicit more evidence of water ice hidden in the craters.

Europe's contribution to this resurgence

in lunar exploration,

began with the launch of Smart-1.

This tiny, ion-propelled satellite

cataloged key chemical elements on the surface.

It also enhanced the theory that the moon

was the result of a collision between earth

and a smaller celestial body called Theias

some four and a half billion years ago.

Japan's second probe was Selene,

better known in Japan as Kaguya.

It continued extensive observations of the lunar crust

and also carried the first high-definition cameras

into lunar orbit,

giving us a clearer picture of the rugged surface.

Another proof of capability, this time by India.

It also carried a NASA mineralogy mapper

and an impact probe.

It played a key role in the confirmation of water

hidden in the southern lunar pole.

Eight months later, NASA launched the

Lunar Reconnaissance Orbiter or LRO.

It has spent the last few years mapping and scanning

the lunar world with sophisticated sensors

and continues to return a wealth of data.

- [Craig] The Lunar Reconnaissance Orbiter is,

as it's namesake says, a reconnaissance mission to the moon.

Our job is to take a suite of very powerful

scientific instruments and make an atlas of the entire moon.

In some places in very great detail.

Topography, mountain heights, mineralogy, temperatures,

abundances of resources, including potentially

the intriguing possibility that there's water at the moon.

We put all of this together and do a data set

by flying low over the moon for a year.

And this is the data that the people,

designing the human systems,

designing the systems, picking the sites,

need to take us back to the moon.

- [Voiceover] This robotic mission commenced operations

in June 2009.

It was hoped the suite of sensors

would fulfill several scientific goals,

not only for the moon, but as a framework

for understanding planetary processes

throughout the solar system.

- [Cathy] The LRO instrument suite

is comprised of six instruments

and one technology demonstrator.

And they are geared towards providing us

a variety of data sets, ranging from

a thermal map of the moon, global topography,

and most importantly, looking for resources

like water ice on the moon.

The entire suite should provide more

of an atlas as opposed to a map.

So that we know where to go on the moon,

where to have the safe landing sites,

and where to put things like lunar outposts

in the hopes of having human exploration

in the near future.

(exciting orchestral music)

(mellow celestial music)

- [Voiceover] The data being returned from LRO

and the other probes,

draws a clear image of the evolution of the lunar surface

and why it is composed of exactly the same elements

as the earth.

After coalescing from the Earth-Theias collision,

the proto-moon cooled,

then suffered several major collisions from orbital debris.

Which created many of the largest surface characteristics,

including the marias.

Cratering continued relentlessly over the millenia

drawing the familiar lunar vista.

(explosions)

- [Lynn] My name is Lynn Carter,

I'm a research space scientist

and I work the planetary geodynamics group

here at Goddard.

I study the geology of planetary surfaces,

the earth, moon, Mars, Venus.

There's a lot of things you can learn about the earth

by studying other planets.

For example, on the earth we have a lot of

erosive processes, you know, it rains,

it washes parts of the surface away.

We have plate tectonics, which recycles the crust.

But on other planets,

those processes don't necessarily occur.

So for example, when we look at the moon,

we're seeing a surface that's much older.

We can use impact cratering on the moon

to sort of understand how many impacts happened,

the size of the objects that were hitting each other

in the early solar system.

One of my favorite things is to use radar remote sensing.

For example, on Mars, we can use radars to sound

all the way to the bottom of Mars' polar caps

and see all this layering within the polar caps.

And on the moon, we're using it to study impact cratering.

Sometimes, when an impact crater's formed

a huge sheet of melt is thrown out.

This melted rock flows across the surface,

but then over time, it's covered over

by stuff from other impacts,

but with the radar, it just blows right through all of that

and you can see this beautiful image

of the melt flow coming out of the crater.

- [Voiceover] Launched with LRO was LCROSS

or Lunar Crater Observation and Sensing Satellite.

It deployed sometime later than LRO

and had a finite mission.

LCROSS and the rocket stage that delivered it

were deliberately crashed into the craters of the south pole

whilst LRO orbited above and observed the impacts.

The debrisent gases thrown up from the lunar surface

were closely studied by LCROSS

as it too descended to the surface.

The missions found evidence that the lunar soil

within these shadowy craters is rich in useful materials.

The moon is chemically active and has a water cycle.

Scientists also confirm the water was in the form

of mostly pure ice crystals,

which have not seen sunlight for billions of years.

LRO has continued to operate in polar orbit,

making observations of the south pole,

and with repeated flyovers, it has drawn up a

detailed map of neutron densities in the region.

Revealing where hydrogen, and thus water,

can be found within the lunar soil.

The importance of this discovery cannot be overestimated.

Having this resource in situ

means independence from the cost and effort

of bringing water from Earth to the moon.

It can be used for creating rocket fuel,

oxygen to breathe, water to consume

and irrigate crops, and used in other processes

to manufacture building materials from the lunar soil.

Launched in 2007, NASA's five THEMIS spacecraft,

have now successfully completed their two year mission

to determine the cause of geomagnetic sub-storms.

Because they are continuing to work perfectly,

NASA redirected the outermost two spacecraft

to the moon.

This new mission was called Artemis,

and they studied the magnetospheric environment

near the moon.

They also observed the effects of surface electric fields

and ions from the solar winds on the lunar surface,

and determined the internal structure of the moon

from variations in it's magnetic field.

- [Bill] Well, in a nutshell, what we're finding

is that the polar craters are very unusual

electrical environments.

Well, the solar wind is actually a relatively tenuous

gas that's emitted from the sun,

but it's not a neutral gas, like the gas in this room.

It's actually a gas that's really, for the most part,

free ions and free electrons.

So as you pass by, for example, a polar crater,

the electrons will actually fill into

the crater ahead of the ions.

Now, as it turns out, as it does that

you create an electric field,

it's called an ambi-polar electric field,

and that electric field then drives in the ions.

- [Voiceover] These hidden troves of water ice

and other volatiles in the polar craters,

may be protected by a dangerous electric charge

of hundreds of volts.

(exciting orchestral music)

- [Voiceover] Three, two, one, zero.

And lift off of the Delta II with GRAIL.

Journey to the center of the moon.

- [Voiceover] GRAIL consisted of two probes

called Ebb and Flow.

Linked together in a single flight path,

they studied the gravitational field of the moon,

generating maps like this crustal thickness atlas.

It reveals much about the interior of the moon,

and even has some surprises.

- [Thomas] Two years ago, we reported evidence

that the moon is shrinking.

Now we've found evidence that the moon is actually

being pulled apart, forming features called graben.

So the shrinking moon, it turns out,

is not shrinking everywhere.

Some places the moon is actually expanding, by a little bit.

So finding these young graben was a real surprise

because we thought, "Well, all these lobate scarps

are telling us the moon is shrinking,

so what are these little small graben,

that are telling us the moon is pulling apart,

doing in this picture?

How does this all fit together?

All that's related to how the moon has evolved.

How the moon has lost heat

over its four and a half billion year history.

Most of the terrestrial planets, when they formed,

were very hot, and they got so hot that they

actually completely melted.

When that happens, they will be in a general state

of contraction because they're still hot on the inside

and cooling down.

And as they cool they want to shrink.

Only the outer part of the moon melted,

forming what is called a magma ocean,

and in that model, the balance of stresses,

or forces that are acting on the moon

would allow us to form both these small lobate scarps,

that show contraction, as well as

these small graben that show the moon being pulled apart.

One of the really, really exciting returns of the

Lunar Reconnaissance Orbiter mission,

is that we've seen this now growing evidence

of very young geologic activity on the moon.

- [Voiceover] The moon's crust is much thinner

on the near side, 68 kilometers thick on average,

and varies from less than a kilometer on the Mare Crisium,

to 107 kilometers thick just north of the crater

Coriolis on the lunar far side.

The moon's mantle is only partially molten,

and the moon's center of mass is offset by about

two kilometers in the direction toward the earth.

This, and other data quickly changed

our understanding of the moon.

To gather more evidence on the unusual

electrical properties on the lunar surface,

and how it effects lunar dust, NASA sent LADEE,

the Lunar Atmosphere and Dust Environment Explorer

to investigate.

- [Rick] At higher altitudes we saw very few

dust particle impacts, but the lower we went,

with LADEE, the more we saw,

and it's a very, very steep rise.

So if you're operating with spacecraft,

very close to the surface of the moon,

as you would with a robotic lander,

or a human lander,

you might need to consider the fact that

you've got more dust there in the way as you come in.

- [Voiceover] This probe flew progressively lower,

and finally impacted on the surface.

- [Voiceover] Ignition. Problem. Main stage.

- [Voiceover] This is Morpheus,

a robotic, self-guided lander.

You tell it where to land, and it will do the rest.

Independently seeking the safest course,

and avoiding any rocky dangers.

The ESA were also developing an autonomous lander

to perform the same function.

- [Bruno] The lunar lander is a small but

very challenging mission.

The most important part of it is of course,

landing on the south pole of the moon.

Which requires innovative solution

concerning landing, hazard avoidance, navigation,

and in fact, this is the mission which will bring about

the new generation of navigation and guidance

sensor, algorithm, and software.

- [Voiceover] But a fiscal year is a long time in space.

NASA now have little interest in returning men to the moon,

they are firmly focused on a Martian landscape.

The Europeans have had budget cuts.

The ESA lander now shelved for the time being.

This leaves the door wide open for Russia

and the younger players, China, India, and Japan.

Plus several private companies,

now developing the same technology

to put first robots, then humans, on the moon.

All this time, the Chinese National Space Administration,

or CNSA, had launched two orbiter reconnaissance satellites,

Chang'e-1 and 2.

Then Chang'e-3 deposited a lunar rover on the surface.

Their latest, Chang'e-5, made a return trip around the moon.

They are firmly set on a permanent manned lunar base.

- [Cathy] I think the reason this has resonated

with so many people, and all over the world,

it's not just our country

is because everyone can look up in the sky and see the moon.

And I think people, a lot of people remember the Apollo

landings, the first man on the moon,

and you can also look up at the sky

and I believe that people,

it's very tangible to them that way.

The moon, they can relate,

so they want to be a part of it.

That's my theory on why people have just so connected.

(exciting orchestral music)

- [Voiceover] The moon is, indeed, a tantalizing prize.

The Chinese have their lander and rover there now.

Japan and India will be next.

South Korea has an interest,

along with Russia, Canada, France, Italy,

and the United Kingdom.

Private enterprise has had the prod

with the Google Lunar XPRIZE,

The 30 million dollar prize pales beside

the glory of being the first private company

to land a robot on the moon,

and to explore at least 500 meters,

and transmit high-definition images back to Earth.

So far there are four hot contenders.

The Barcelona Moon Team,

a consortium of companies headed by

Galactic Suite Design.

Their interests lie in space technology and industry,

with a strong focus on tourism.

Penn State Lunar Lion Team.

Faculty and students are developing a spacecraft

to land on the moon, then lift off again and relocate

to fulfill the prize requirements.

Moon Express is a group of space and

Silicone Valley entrepreneurs,

looking to mine the moon for it's valuable resources,

like platinum, titanium, and the rare isotope Helium-3.

Finally, Astrobotic Technology.

A Pennsylvania based company

with support from other companies

including ALCOA and Caterpillar.

They have already reserved a launch

on a SpaceX Falcon-9 launch vehicle.

Getting to the moon is one thing,

staying there is another.

- It was one thing to go for a handful of days in Apollo,

and go when you knew the sun was quiet,

or you hoped the sun stayed quiet.

And you took the risk,

you calculated the risk of cancer and such,

and you made a short mission.

If you're going to live there longer

you need to understand it well enough to go,

"Here's what I need to do to protect myself."

- One of the things that we're looking for

in the LRO mission is

how the high-radiation environment

effects our ability to explore.

So if we bring cameras or communication devices,

you know, how will they be impacted by

the cosmic radiation.

We need protect our equipment as well as ourselves.

- [Voiceover] We want to be able to go back to the moon

so that we can live there for long periods and

work on the moon.

So we need a mission that can help us find

the best places to go and determine

how to go back there safely.

- [Voiceover] Access to solar power, continuously,

that may be the first and most important reason

over the near term.

And then the possibility of resources being there.

Those may take much longer time before we're able to

really exploit those,

but the solar power is something we can exploit right away.

- [Cathy] Whether it's water ice to have water,

or potential minerals that we could use as raw materials

to make into things that we would need.

- [Voiceover] All the major players have designed

and planned many varieties of lunar bases.

NASA, ESA, and private contractors

have concepts on the drawing board.

As more information comes in from the lunar satellites

on the environment, resources,

and dangers of cosmic radiation,

these plans evolve.

One of the latest is to use 3D printing technology.

(upbeat electronic music)

With all the challenges and difficulties,

many have made firm commitments

to establishing bases within 10 to 15 years.

Some for scientific research,

others for commercialization and tourism.

Some would choose not to send test pilots and scientists,

but stewardesses and sommelier.

- [Craig] When we look back on what we did in LRO

and we look at what followed,

I think we'll see a profound impact.

We'll see us as really being the small first step

where we have human beings permanently off this planet.

Beginning to move out into the solar system,

starting with the moon.

If that pans out, I think we'll be a small piece

of a profound development that when history looks back

they'll say, "This time we went back to the moon,

this time we stayed, and then we moved on from there."

- [Voiceover] As we continue to study the moon

our understanding of it improves,

giving us new insights, not only into

how it has evolved over time,

but also how other rocky planets in our solar system

have come to look the way they do.

With new missions, new instruments, and new technologies

we will continue to improve our knowledge of the moon

and better understand the history of our solar system.

(exciting orchestral music)