Original subtitles

WILLIAM SHATNER: Genetically-modified astronauts,

massive underground bases on Mars

and futuristic rockets that will send humanity

across the universe.

Humans have been traveling through space

for more than 60 years, and during that time,

we've put men on the Moon and robots on Mars.

But how much further can we go?

Will we be able to send astronauts

to the far reaches of the universe?

And when we arrive on these strange new worlds

will that make us...

alien earthlings?

Well, that is what we'll try and find out.

♪ ♪

SHATNER: Since the dawn of humanity,

Earth has been the only home we've ever known.

Mankind has explored, settled

and conquered nearly every nook and cranny of our planet.

Now, tens of thousands of years into the age of modern man,

it seems that the only place left for us to go

is up.

GRAHAM LAU: For all that we know from our history,

we humans are explorers in our very nature.

And so, it seems to make sense that we would want to go out

and explore the other worlds of our solar system and beyond,

and maybe even settle there

to send people to live, perhaps permanently,

in the other worlds that exist out there.

MICHIO KAKU: It is a law of physics, practically,

that one day, we will have to leave the planet Earth.

We have to have an escape clause

in case something devastating happens

to threaten the very existence of human life.

In fact, one of the goals of NASA is

to create a Martian colony with human inhabitants.

And so, why not this be the destiny for humanity

to become a multi-planet species?

But then, the bigger question is

is it possible?

SHATNER: Could humans really become a multi-planet species?

For over a century,

science fiction and fantasy have explored the concept,

but what would it actually take

for us to become alien earthlings?

BEN McGEE: One of the greatest challenges

in sending humans off-world is that frontier explorers

in outer space are gonna face hazards,

the likes of which no humans have had to face.

It's barren and inhospitable,

there's a lack of oxygen

and lack of resources in space,

so, it's treacherous.

Self-sufficiency is going to have to be key,

and it's gonna be a struggle.

SHATNER: The Baikonur Cosmodrome, Russia.

April 12, 1961.

A Vostok 1 rocket launches into the sky,

carrying only one passenger--

Soviet cosmonaut Yuri Gagarin.

For 108 minutes of a single orbit around Earth,

Gagarin becomes the first human being

to leave our planet and journey into space.

McGEE: Yuri Gagarin is

literally the first alien earthling.

He was up there for only about an hour,

on a Vostok rocket,

and this is only a little bit more generous

than a cannonball with a human being inside,

fired all the way up into space and then falling back.

So, truly, these first cosmonauts

were pioneers putting themselves at risk.

Yuri was regarded almost universally as a hero.

(cheering)

He was celebrated the world over

as the first human being in space.

AMY TEITEL: Gagarin's flight took all of America by surprise,

and everybody suddenly kind of stops what they're doing

to learn about this, to watch the newsreels.

And in the 1960s,

everything about space flight was unknown at the time.

They didn't know if astronauts were gonna lose their minds

and space madness would kick in.

Also, there were questions like, "Will your eyes distort

"without gravity, and you can't see?

Can you swallow without gravity?"

No one knew anything,

and then Yuri Gagarin goes into orbit.

And the reality of humans going into space is suddenly here.

SHATNER: In a speech at Rice University,

President John F. Kennedy announces an audacious plan.

Just 17 months after the first manned orbit of Earth,

America is planning to put a man...

on the Moon.

We choose to go to the Moon in this decade

and do the other things,

not because they are easy, but because they are hard.

SUSAN KARLIN: JFK announcing

that we were gonna go to the Moon

ignited imaginations.

It was tremendously exciting for the American public.

However, the engineers that actually had

to make it happen were a little unnerved

because America was still at the infancy

of getting into space.

At that point, we really didn't even know what we didn't know.

Now, this was a very dangerous thing to do,

because the Apollo lunar missions were flown

right on the edge

of what are called "single points of failure."

If a certain rocket engine didn't ignite,

they couldn't leave the surface of the Moon.

So, it puts astronauts in significant danger.

But this was the nature of spaceflight then.

We were taking a lot of chances.

SHATNER: In less than seven years

from JFK's bold proclamation,

and with the help of over 400,000 scientists,

engineers and NASA personnel,

Apollo 11 launches into outer space.

SHATNER: After a journey

that lasts four days, six hours, and 45 minutes,

the lunar module lands on the Moon.

TEITEL: When Apollo 11 landed on the Moon,

everyone kind of stopped to watch,

because I think there was probably

this almost morbid curiosity of like,

"If this works, this is amazing, and if this doesn't work,

I want to see what's gonna happen next."

I mean, whatever was gonna happen, you had to see it.

KARLIN: The Apollo 11 Moon landing was astonishing.

I mean, people were glued to their TV sets,

riveted by the fact that there were two men on the Moon.

And then you'd go outside,

and we'd look at the Moon, and say, "Oh my God,

there are actually two people on there right now."

And it was mind-blowing.

SHATNER: After the success of Apollo 11,

NASA landed ten more astronauts on the lunar surface.

But after three years and six manned missions,

in 1972, the United States

shut down the costly Apollo program.

And since then, humans have not been back

to Earth's closest neighbor.

But could the Moon serve a strategic role

in our quest to explore the solar system?

The White House. December 11, 2017.

President Donald Trump signs Space Policy Directive 1,

which authorizes NASA to send astronauts back to the Moon.

And, incredibly, the initiative also sets the stage

for the construction of the first-ever moon base.

TRUMP: The directive marks an important step

in returning to the Moon.

This time, we will not only plant our flag

and leave our footprint.

We will establish a foundation for an eventual mission to Mars,

and perhaps someday, to many worlds beyond.

KAKU: We're entering the second golden era of space exploration.

The first golden era took us to the Moon,

but it is a whole new ballgame now.

Realize that there's a plan,

there's a design behind all of this.

We're talking about an interplanetary highway system

that goes between Earth, the Moon and Mars.

In other words, it's different from all other missions.

SHATNER: While the idea of a moon base that will allow us

to travel to deep space sounds like science fiction,

NASA plans to invest more than $100 billion

in making it a reality.

The program is called Artemis.

-Your Artemis 2 crew! -(applause and cheering)

SHATNER: And a mission to land both a man

and the first woman on the Moon will take place in 2026.

Once we've returned to the Moon, the next stop is Mars.

LAU: Going to Mars from the Moon

requires a lot less fuel to begin with to get us there.

That leaves more mass for us to send things like extra water,

extra food, more people,

to prepare us for other kinds of exploration, like

going to the other worlds of our solar system.

SHATNER: Will humans succeed in colonizing Mars,

and perhaps even more distant planets?

It's an exciting thought,

but in order to become alien earthlings,

we first need to figure out how to protect astronauts

from the dangers that they will encounter...

in outer space.

SHATNER: For over six decades,

mankind has made tremendous progress

in space exploration.

From satellites and probes to robotics

and a manned space station,

we continue to test the boundaries of humans in space.

But while the idea of becoming alien earthlings

fills us with wonder,

the harsh reality is that the vacuum of space is lethal

to the human body.

We very much evolved to live

on the surface of a world like the Earth.

But space is very hostile for life as we know it.

The space environment itself is extremely cold.

There's not enough oxygen for humans to breathe

in the vacuum of space.

There's also radiation coming from our Sun,

coming from other stars.

And there are other dangers,

things like micrometeorites

and other possible objects

that can strike astronauts when they're in orbit.

And so there's a lot for us to overcome

when it comes to the challenges of space.

PYLE: The problem with human beings is we're basically fragile things.

We're big, mushy, wet bags of muscle and water,

and everything about space wants us dead.

So, when you go into space,

you're always kind of flirting with the edge of disaster.

SHATNER: As earthlings venture further off our planet,

how can we protect the human body

from the dangers of space travel,

especially when an astronaut's carefully designed clothing

and equipment could be the difference between life

and death?

Four years before the Apollo 11 moon landing,

Soviet cosmonaut Alexei Leonov

prepares to boldly go where no man has gone before.

One of the earliest tales of extreme danger in space

was during the Voskhod 2 flight of the Soviet Union

back in the early 1960s.

This was the first spacewalk ever.

Alexei Leonov was to depart the Voskhod capsule

in his pressure suit

to basically drift for about 12 minutes.

He was at extreme risk of suffocation or worse.

SHATNER: On March 18, 1965,

the two-man crew of Voskhod 2 reaches orbit

and Alexei Leonov prepares to be the first human

to set foot in the cold vacuum of space.

PYLE: They open the hatch.

The cosmonaut drifts in space.

Looks like he's having a great time, but, in fact...

...his suit pressure was increasing.

The suit was becoming very rigid,

and he suddenly realized that the suit had inflated so much,

he wasn't even able to reach down and trigger the camera

to take the pictures he wanted to

and he couldn't fit through the hatch anymore.

(yelling in Russian)

Leonov's over-pressurized suit had ballooned to the point

that he could barely move...

...leaving him stranded in space,

nearly 120 miles above Earth.

To save his own life, Leonov had to think fast.

Leonov had to sit there and manually bleed off air pressure

from a little valve...

...on his space suit and depressurize.

He did eventually depressurize enough

to get back inside the capsule.

By that time, he estimated that he had

between two and three quarts of sweat

sloshing around in his boots from the exertion.

He could have easily passed out and died.

SHATNER: The harrowing story of man's first spacewalk

is a stark reminder of the grave dangers astronauts face

when confronted by the harsh reality of outer space.

But could even the best technology and fabrication

create suits that could truly protect future astronauts?

Or does the answer to human survival in space

include modifications on a cellular level?

The International Space Station. May, 2019.

NASA astronaut Christina Koch

conducts a revolutionary experiment in zero gravity.

Using a technology known as CRISPR,

she is able to repair genes inside yeast cells.

But what is the purpose of this radical experiment?

Could this technology be the solution

to modifying humans for survival in space?

There's something called transhumanism,

which is the movement to try to perhaps prepare for the day

when we have to genetically modify ourselves

to explore the universe.

Eventually, we may use genetic interventions

in the form of CRISPR technology

to change our genes and our body organs biologically

so that we can adapt to hostile environments in outer space.

REBECCA BOYLE: This experiment in microgravity

shows that we have a lot to learn

about how to optimize humans for space travel,

and one of the most important things to do

would be to survive the radiation environment in space.

If you leave Earth, you no longer have Earth shielding you

from cosmic rays

and really damaging radiation...

...that can harm our DNA...

...and do things like cause cancer.

So it would be interesting to find out

if there are ways to manipulate our genetic material

to make it less likely for us to suffer those health effects.

SHATNER: Will CRISPR technology help us rewrite our DNA

to withstand deadly radiation

while traveling through outer space?

Perhaps.

But what about other side effects of living off-planet,

like the weakening of bones and muscles?

One potential solution involves augmenting the human body

with advanced robotics.

KAKU: Our bodies, because of evolution,

are fine-tuned

to exist in a gravitational field

of the planet Earth.

So, as we explore outer space,

we're getting weaker and weaker.

Some people say that it might be possible to compensate

by using modification devices called exoskeletons.

Believe it or not,

we can connect the human brain

directly to a suit of armor

that is controlled artificially.

For example, a few years ago in Brazil,

the World Cup soccer game was initiated

by a man who was totally paralyzed.

And the scientist connected his brain...

...to an exoskeleton

to enhance his mechanical abilities.

In the future, it'll be streamlined.

Astronauts would have this suit on

and would have, in some sense, the superpowers of Iron Man

on a distant planet.

LAU: There are many challenges,

and there are certainly a lot of questions involved

when it comes to modifying what the human is.

But it still makes sense that if we truly want to go out

and explore the stars that we would choose

to change ourselves to fit the space environment.

Will astronauts become robotically enhanced

and genetically modified alien earthlings?

It's a fascinating prospect.

But in order to reach distant planets,

we have to do more than protect our bodies.

We also have to create new rockets that can take us

across the vastness of space.

SHATNER: As part of its Apollo program,

NASA prepares to test its newly designed

super heavy-lift launch vehicle,

the Saturn V rocket.

MAN: We have ignition.

All engines are running.

We have liftoff.

SHATNER: Built specifically for human exploration of the Moon,

the Saturn V rocket would successfully launch

26 astronauts into space.

But this monumental achievement

would require a massive vehicle

in order to propel man into lunar orbit.

The problem with the Saturn V rocket

is it's, like, 12 747s all stacked together.

And then when you look at what we actually sent to the Moon,

the lunar lander and the return vehicle,

that was about 35,000 pounds' worth of payload.

But the Saturn V rocket itself was 6.5 million pounds.

That means more than 99.5% of the system

was the rocket that didn't go to the Moon.

PYLE: Traditional rocket engines are very effective

for short distances, but what they don't do well

is run for extended periods of time.

And if you really want to go deep into the universe,

you need something that's ultrareliable, very simple

and can run for hours and hours and hours.

SHATNER: While the concept of deep space travel

has both entertained and inspired us for over a century,

the question remains, how will humans cross the vast distances

it takes to get to other planets?

Will scientists and engineers

be able to create next-generation rockets

that will take humanity further and faster than ever before?

NASA makes a surprising announcement

about the future of space travel technology.

They intend to build a rocket called DRACO

that is driven not by conventional fuel

but rather by one of the most powerful and hazardous forces

known to man:

nuclear reactions.

MICHAEL DENNIN: When we think about nuclear rockets,

it's very different than an atomic bomb.

With an atomic bomb, you're actually creating an explosion

from the nuclear fusion reactions.

When you think about a nuclear engine,

it's a lot more like a nuclear reactor,

which is much, much more efficient

and takes a lot less mass.

McGEE: With a normal rocket,

you need fuel so it'll burn,

and that's what provides thrust.

But with a nuclear rocket, nothing burns at all.

You just take a really cold liquid,

pump it really fast through a nuclear reactor,

and you just let it go.

And it's basically

twice as fast as our best rockets today

using half the fuel.

PYLE: DRACO will solve a lot of problems.

This is something that can go longer distances

faster, more efficiently, than anything we've used before.

For instance, going to Mars,

the chemical rocket could take up to seven months.

Nuclear rockets will be able to cut those times down

by anywhere from 30% to 50%.

So, it makes it

a lot easier for people to go

from one place to another.

SHATNER: NASA has announced that DRACO will be ready

for its first test flight in 2027.

But assuming the rocket is successful,

we still have another problem to face.

Because even with the fastest space ships imaginable,

traveling to other worlds

will take longer than the average human's lifetime.

The biggest challenge with being multiplanetary

is the vast distances between the planets.

Going to another planet, even with our fastest spacecraft,

would require hundreds of years.

Or even thousands years, quite possibly.

And so, this would be

an unprecedented journey for humanity.

I just don't know who would sign up

to live and die on their way to a new planet.

SHATNER: How can we ensure that astronauts will survive

extremely long voyages across the universe?

Well, one of the methods that is actually being

seriously discussed sounds like something

taken right out of a science fiction movie.

It's referred to as cryosleep.

The idea of cryosleep has been around in science fiction

for a very long time,

this idea of an induced hibernation

to allow human passengers on a spacecraft

to basically sleep for the ride.

If we can bring their metabolism down low enough,

just to sleep and to rest,

it means, psychologically, they don't have to spend

many years on a spaceship slowly traveling through space.

This is kind of an idea that seems

far-fetched to some people,

but if we look at animals all around our planet,

we see kinds of examples of hibernation already.

MASON: We know it's possible in a mammalian system

to go into hibernation...

...because bears routinely do this every winter.

They go hibernate.

We just haven't figured it out for humans yet,

but it has a lot of promise.

SHATNER: Could hibernation be the answer to the problem

of long-distance spaceflight?

It's such a promising solution

that NASA is already coordinating with a company

called SpaceWorks to develop

a crew module that will put astronauts into

a deep sleep by gradually reducing their body temperature.

If this technology is successful,

it would mean that the first alien earthlings

would literally snooze their way

to other planets.

PYLE: The idea is that

one of these spacecraft would be the size of a small city.

You could have people in their recliners

in the main deck.

You could have computerized control systems and so forth.

This idea has been around for a long time,

and it's something we think we can do

within the next ten years.

Just imagine what it would be like to spend months

or even years in a deep sleep

and then suddenly wake up

on another world.

It's a mind-bending thought,

but perhaps the bigger question

is can earthlings really live on alien planets?

One solution may lie in new technology

that will allow humans to breathe

on Mars.

SHATNER: Scientists at NASA's Jet Propulsion Laboratory

wait in eager anticipation

as some 127 million miles away from Earth,

the Perseverance rover

hurtles at more than 12,000 miles per hour

toward the surface of the planet Mars.

KIRSTEN SIEBACH: The Perseverance rover

is about the size of a small SUV,

so it's a pretty big car that were driving around on Mars.

And we've got cameras on the end of the rover

so we can look around

and take pictures.

And then have a lot of scientific instruments

so that we can understand

what Perseverance is seeing on the surface of Mars.

KAKU: The Perseverance rover

is scouring the entire surface of Mars.

Now, why is that important?

And the answer is

all of this is in preparation

for one day putting humans on the surface of Mars

sometime after 2030.

SHATNER: Both China and the U.S. have plans

to send astronauts to explore the Red Planet

in the next few decades.

Could a successful mission to Mars

lay the groundwork for building long-term settlements there,

as many have imagined?

McGEE: When talking about

future human settlement,

eyes always turn to Mars.

But the Martian environment right now

is completely inhospitable.

It has almost no breathable oxygen

and it's ice cold.

These are extremes

the likes of which no human being could survive.

SHATNER: If we're to become alien earthlings,

then we have to find a way to survive on other worlds.

But how can we protect future colonists

from the harsh environment they would endure on Mars

over a long period of time?

One solution may be hiding in plain sight.

The Mars Express satellite is conducting

a scan of the planet

when it spots something remarkable.

It captures detailed images of strange formations

that look like veins running across the Martian surface.

Experts believe that these curious features

are part of a vast network

of underground lava tubes.

ROBERT SCHOCH: Lava tubes are the result of

volcanic activity and lava flows.

We know this well 'cause we can see them on Earth.

So, when a major volcano on Mars

spews out lava, what happens is that

the lava flows.

And when it flows,

the surface of the lava

cools more quickly than the interior,

and it forms a crust and it leaves these tubes.

And these tubes can be huge.

SHATNER: When NASA analyzed photos of Martian lava tubes,

they estimated that these underground caverns

measure up to 1,300 feet in diameter,

wider than most sports stadiums.

This has led many experts to theorize that living underground

in Martian lava tubes

may be the best way to efficiently shelter

the first human colonists on Mars.

SCHOCH: You can have a tube that's big enough

in circumference and diameter

to have a house inside.

They can extend for tens of miles or more.

So, these would be

incredible havens on Mars

for human habitation.

SHATNER: The possibility of

using lava tubes on Mars

as long-term living quarters for humans,

has prompted NASA to conduct a dress rehearsal

here on Earth.

A research station called HI-SEAS

has been constructed on Hawaii's big island,

where astronauts train in natural lava tubes to

prepare for colonizing off-planet.

LAU: NASA certainly has had a very large hand in finding ways

to create colonies or habitats

inside of these places.

That shows us that

using the resources that are available

locally on Mars, we can build up

the different structures we would need for a habitat.

SHATNER: Will the first humans who travel to Mars

build shelters inside its massive lava tubes?

Perhaps. But rather than living underground,

some experts have proposed a far more ambitious plan

that will radically alter the Red Planet.

NASA announces they have successfully conducted

a landmark experiment on the surface of Mars.

Called MOXIE, the extraordinary test

utilizes a sophisticated device

to convert small amounts of carbon dioxide

into breathable oxygen.

MOXIE is this really awesome test bed package

that we put onto the Perseverance rover

and sent to Mars.

It's basically trying to find ways

that future explorers can produce oxygen

for humans to breathe.

PYLE: MOXIE is basically a little box

that compresses Martian atmosphere,

heats it up, runs it past some kind of catalyst,

and extracts oxygen.

They'd hoped they could run it maybe five times.

They've run it many more times than that.

It's been an outrageous success.

LAU: MOXIE itself is just a demo.

It only produced a little whiff of oxygen for us.

We definitely have to enlarge it far more

to allow enough oxygen for humans to breathe.

But that, by itself, shows us that we can do it.

And if we can have oxygen on Mars that we can use,

then that solves a huge problem.

It's inspiring to think that, in the near future,

we might be able to not just survive

but actually thrive on other planets.

But what if we are not

the only ones living there?

What happens when we come face-to-face

with another civilization who thinks that

we are the aliens?

SHATNER: As humanity prepares to send astronauts to Mars

and then, eventually, to even more distant planets,

it begs the question:

will we encounter alien beings

when we arrive on these strange new worlds?

And if so, how will we communicate with them?

LAU: This question comes up a lot in astrobiology

and with the public.

How will we talk to an advanced, intellectual,

alien civilization, or could we even do that?

And honestly, the concept is difficult

because we don't know

what aliens are going to look like,

let alone understanding the intelligence

of an alien civilization,

and so, we may not be able

to immediately have a communication.

SHATNER: Will it be possible to bridge a communication gap

between earthlings and extraterrestrials?

It's a question scientists have been pondering

for over 50 years.

On a rugged mountain slope stands a complex

of large telescopes known

as the Byurakan Astrophysical Observatory.

In 1971, the observatory was the site

of a meeting of the world's top astronomers, called

"The First Soviet-American Conference

on Communication with Extraterrestrial Intelligence."

PYLE: Carl Sagan, who was a very prominent scientist at the time,

and Frank Drake, who started and runs

the Search for Extraterrestrial Intelligence,

came together with some other people,

and this was the first really structured and well-ordered,

rational scientific attempt

at talking about communication

with an extraterrestrial civilization,

something that up until then

had not been talked about a whole lot.

SHATNER: Less than a year after the conference,

Carl Sagan and Frank Drake came up

with one potential solution

for how to establish some form

of communication with extraterrestrials.

They designed a small aluminum plaque

that was attached to NASA's Pioneer 10 probe,

and sent into space.

The engravings on the plaque were a rudimentary first step

towards one day talking with beings from other worlds.

TEITEL: On this plaque,

there is a drawing of an adult man and an adult woman

to kind of show average height.

There's also a picture of the spacecraft,

and that shows the size of humans

with respect to the spacecraft.

There is a map of where you can find the Earth

in the solar system.

The idea being, if some extraterrestrial life

eventually finds this thing, they might be able to figure out

a whole lot of information about us,

including what we look like.

We thought we would put a message on it

to indicate a little bit of where we are,

when we are and who we are.

LAU: Even though aliens might have a very different form

of communication, perhaps

there could be some universal patterns

that communication follows

to look for when we're speaking to aliens.

SHATNER: The Pioneer plaque sparked fascination

that, as difficult as it may seem,

it may actually be possible for us

to successfully communicate with extraterrestrials.

But since the 1970s, the thinking

around this question has dramatically changed.

Many experts now warn that when earthlings travel

to alien home worlds, our first encounter...

might not be friendly.

In our science fiction or folklore,

it's always the aliens who come visit us,

and it's about our reaction to the aliens.

But let's turn the tables.

As we explore outer space,

maybe, just maybe, we are the aliens.

Maybe we are the ones encroaching

on other people's backyards.

So, when we make first contact with an alien species,

I think we should do it very carefully.

SHATNER: Is it possible that when earthlings arrive

on distant planets, aliens will not welcome us with open arms?

Unfortunately, many astronomers think the answer could be yes,

including the late Stephen Hawking,

who famously warned

that extraterrestrials might look at us the way

we look at bacteria.

KAKU: If aliens are thousands of years more advanced than us,

then they could easily overcome our weapons.

And so, instead of embracing aliens

from the stars, we should realize,

"Hey, let's-let's take a few steps back."

SHATNER: If we come face-to-face with extraterrestrials,

will they be hostile?

Or might earthlings and aliens be able

to peacefully communicate and coexist?

It's an intriguing mystery,

but for the moment, the more pressing question

is whether humanity will choose to dedicate

the vast amount of resources it will take

to live on other worlds.

SHATNER: Aerospace company SpaceX launches a crucial test

of its interplanetary rocket, called Starship.

According to SpaceX's billionaire CEO Elon Musk,

Starship will help humanity evolve

beyond our home world.

KAKU: Elon Musk

has a dream, and his dream is to create humanity

as a multi-planet species,

and that's why he's building his own rocket ship,

whose design is to become the bulwark

of an interplanetary network of rockets

to go between planets.

SIEBACH: Collaborations with companies are really critical

to space exploration, because private companies

think about that technology development

in a different way than NASA does.

And that's really helpful.

PASCAL LEE: Elon Musk

and Jeff Bezos, with Blue Origin--

both were inspired by the Apollo program.

They really took those directions

in their lives because

they were so inspired by the possibility of space travel.

And so, if you have somebody who is single-minded

and running a company that is possibly able

to get to a place like Mars,

you actually root for that

because it might actually happen.

SHATNER: While the involvement

of private companies is an exciting step

towards living on other worlds, it doesn't come cheap.

For example, it's estimated

the massive Starship rocket will cost ten billion dollars

in research and development.

This high price tag raises the question,

is space exploration worth such a huge investment?

Experts believe the answer is yes,

because the fate of humanity

may depend on becoming a multi-planetary species.

MASON: A big question is not just

"can we do this" but "should we do it?"

And I think that we really have no choice.

Becoming multi-planetary gives us the first sort of

backup plan for humanity.

So, if something goes horrifically wrong,

or an asteroid hits,

we become the stewards of life and enable it

to live on more than one planet.

SHATNER: With all the time,

money and effort being invested

in next-generation space programs,

it makes you wonder what milestones

will we reach in this century

and the next?

TEITEL: Humans have this

insatiable need to explore,

to push the limits of what we can do,

of what we can survive.

And that's really what kind of got people

wanting to go into space in the first place.

And today, it's not limited to the U.S. government

and these private companies.

We're seeing other countries also have

these deep space missions.

And now, everybody wants to be involved in space somehow.

SIEBACH: This is such an exciting time

to be a part of space exploration.

There are more groups working on this

than there have ever been before.

All of these developments are absolutely thrilling,

and that's clearly motivating

a lot of people right now.

MASON: I believe humans inevitably

will be on multiple planets,

that we have this in our nature,

we have the capability, we have the technology.

It's really just a question of willpower and time.

We have to consider using all the tools and technologies

at our disposal, but we won't know until we try.

Daring to venture into the universe is perhaps

the single greatest endeavor in human history.

Thus far, the progress we've made

exploring the final frontier is truly inspiring.

Do we have the right stuff to reach distant planets

and become alien earthlings?

Well, let's hope so. But for now,

the answer remains

unexplained.

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