Original subtitles

The Earth is doomed.

A devastating force is coming.

And we're running out of time.

As civilization crumbles around us and the world is destroyed, can we build

spacecraft to take us to new, habitable worlds?

Can mankind escape annihilation?

Can we?

evacuate Earth.

Is that

a

shooting star?

Oh wow, yeah, look at that one.

The ups and downs that we've experienced as a species are nothing compared to

what the universe can throw at us. Now, there's a whole list of bad things that

can happen to a planet like the Earth.

My god.

Get in the trunk. Get in the trunk!

Get in the trunk!

If we were suddenly bombarded with a shower of large objects from space, that

would be catastrophic for Earth, and it would mean many different things, but

none of them are good.

One of the most extreme possibilities we can think of would involve an object

that we call a neutron star.

Now, a neutron star is incredibly compact, and that size means that its

brightness can be a million times less than that of the Sun.

A neutron star is a stellar corpse.

A star much more massive than the Sun burns through its fuel extremely

And at the end of its life, when it runs out of fuel, the entire core of the

star simply collapses.

This creates one type of supernova in a massive stellar explosion.

If we determine that a neutron star was really headed in our direction, that's

very bad news. You can't blow it up. You can't change its direction.

You can get out of its way.

or you can suffer the horrendous consequences of being destroyed by a

star.

One of the problems with our current age, which can be a good thing depending

upon what the issue is or a bad thing, is that people are very cynical.

We don't particularly believe what we see and hear.

And you can imagine you'd have various people, various scientists, get on the

talk shows and say, no, this is really happening.

Do you mean the same thing could happen to us?

Yes, I believe it will.

And just about every astronomer in the world believes it, too. We've all read

the same data.

So within a week or two, people will believe it.

But the real question is, what will they do about it? And when would this

happen? By our best calculations, 75 years.

75 years.

The Earth will be destroyed. This is the end of Earth.

If nature throws something at us that is so utterly catastrophic that the

Earth... would be utterly destroyed.

That would compel us, I think, to try to go elsewhere.

It boggles the mind. Can we really rescue 7 billion people?

You have to remember only about 600 people have ever gone into space in the

entire history of the human race.

And then there's the problem of the distance that we're going to have to

them.

We're probably going to have to go six, seven, eight light years at least, and

that's 40 trillion miles.

One thing is pretty certain.

We're not going to get there using the space vehicles that we have now.

To make this work, we're going to have to build an absolutely colossal ship,

we're going to have to develop a new type of engine to propel it. The

is, can we?

Any plan to build a new space drive comes with great risks, but with the

humanity at stake, we're going to have to accept those risks however great.

We've titled the project Horizon, and it represents...

The cutting edge in spacecraft propulsion technology.

We're going to be looking at a few approaches right now.

Plasma.

Promising, but it poses some real problems with regard to fuel and fuel

But this is a contender.

To make a rocket able to accelerate you to high speeds, the faster you can shoot

the exhaust out, the better off you are.

The idea of a plasma rocket is that we'll use electricity.

to accelerate our gas.

And so then you can shoot things out to very large velocities.

But plasma, while it is more powerful, would probably require a lot of fuel.

So really that puts us back to square one with the fuel problem.

Solar sails. This technology has the advantage of substantial research,

especially in the last 15 years.

A solar sail derives its propulsion from sunlight.

You can't feel it when you're out walking on a sunny day, but the light

reflecting off of you is pushing on you.

And we've looked at designs of solar sails that, if they're large enough and

lightweight enough, can get to very, very high speeds.

The solar sail has an Achilles heel, and that is it receives its acceleration by

radiation pressure.

From the sunlight, from the sun. And as you get farther away from the sun, that

radiation pressure gets weaker. The sunlight gets weaker as you move away.

It's kind of like driving on a long, lonely highway, and there's no gas

suddenly for many, many miles.

There's another candidate for an interstellar drive, and this one seems

straight out of science fiction.

Antimatter.

Antimatter is the fondest hope of every propulsion engineer for the last two

decades. Antimatter is kind of the mirror image of matter.

It has the same mass as a normal particle, like a proton, an electron,

has different charge and spin.

And what is really interesting is if you bring a matter particle and an

antiparticle together, as soon as they interact, they annihilate each other,

this releases enormous amounts of energy.

But antimatter presents serious challenges. All that energy is really,

dangerous. And we don't necessarily know how to control it, much less funnel it

through an engine.

When we make it, we have to store it in a vacuum chamber and contain it in some

very strong magnetic field so that it doesn't interact with the walls of the

chamber. Because if it does, it's going to annihilate and produce energy.

And just in layman's terms, it becomes a very, very large bomb.

So here we are. We can't use chemical rockets.

Solar cells eventually will run out of thrust.

And antimatter is too dangerous. So that's pretty bad news for a vessel

designed to travel to distant stars.

Thank you all for coming. We're going to break now and get into our discussion

groups.

But we might have an ace up our sleeves.

There's a technology that might work very well.

The irony is that this technology is not new. It's over 60 years old, and it

might just hold the answer.

So during the Manhattan Project in the 1940s, there was a physicist, Stanislaw

Ulam, and he proposed launching a massive space vehicle that was propelled

nuclear bombs.

A number of scientists, including Freeman Dyson, took this concept to the

level, imagining a spacecraft that would be propelled by nuclear explosions.

And they called it... project orion orion is really very simple in

in concept imagine that you have a very large spacecraft and on the back of it

you put big plates with big shock absorbers and what you do is you take

bombs and you eject them from the spacecraft and they go some distance

perhaps tens or hundreds of meters they explode and the blast wave hits this

pressure plate

and you set off multiple of these detonations where it's bang, bang, bang,

the thing gradually starts to move along and accelerates up through a high

velocity.

The fastest man -made object now is the Voyager probe, which is going at 0 .006

times the speed of light. At that speed, it'll take it tens of thousands of

years to reach another star.

But with Project Orion, we can go much faster.

Studies that have been done show that if you were to detonate a bomb behind it

once every three seconds for ten days, you would get up to a significant

fraction of the speed of light.

To conceive and build such a vessel is going to take cooperation on a scale

never before seen in the world.

We're talking about natural resources.

We're talking about economies of the world having to give up the concept of

money, working toward a common good.

They're calling it the Horizon Project.

And we've been granted exclusive access to show you this sprawling compound as

it arises from the soil here in Florida.

They've already dubbed this complex Starship City. In a few months, this

will be secured by the military, and the fight to save humankind will begin.

You bring the community to Starship City.

You bring all of your scientists and engineers there, and then you start to

the design work.

They need to have homes to live in.

And it's not just them, it's their families, because they have wives or

and children which might come with them.

And it becomes a massive community which needs supporting.

Now the first order of business at Starship City will be to figure out how

actually build the Orion and make it work.

The first thing you'll have to do is increase the production of plutonium.

have to design the bomblet to be specifically used for Orion.

You wouldn't be able to use a decommissioned nuclear weapon from our

you've got a whole new design effort for building these.

As you can see, the bomblets are going to be delivered to the pusher plate.

that are used for propulsion have to serve a couple of purposes, and that

them complicated to design.

One is they have to transfer the momentum of the detonation of the bomb

off to push the spacecraft.

They have to provide radiation shielding for the occupants of the spacecraft.

Being around a hydrogen bomb going off is not exactly a healthy environment to

be in unless you're behind a lot of shielding.

And it has to survive that.

Multiple detonations, one every three seconds, as this thing is being

One detonation every three seconds could get us to a respectable fraction of the

speed of light, possibly even 7%.

So while we're perfecting the propulsion

system, the next question will be, what exactly is it pushing?

How big will it be?

And what conditions will we need inside of it?

to prepare for the passengers.

One of the critical environmental elements that we're going to have to

is one that we take for granted here on Earth.

And that's gravity.

When you go into space, if you don't have gravity, one of the first things

starts to happen is that the bones in your body suffer calcium decay.

If you ever see guys that have come down from the International Space Station

that have been in space for three months, when they get out of their

they have to be supported. They literally will fall down. They're so

Now we're talking about an entire lifetime spent in zero gravity.

And so there's a whole host of problems. Number one will be the fact that I'm

not sure if we can actually have men and women produce children in this

environment. The reproductive system relies on gravity.

We don't even know what a body that grew in zero gravity from infancy or even

from in the womb would look like. Would it operate like ours? Would it even be

feasible to give birth in interstellar space?

We have to assume that we will be raising at least several generations of

humanity in space.

And this is something that's never been done before.

Fortunately, there are fairly easy ways to simulate the effects of gravity, and

one of those is through rotation.

Gerard O 'Neill is a professor of physics at Princeton University who

the design for a space colony where people would live on the inside surface

rotating cylinder to produce artificial gravity.

This has all been simulated in computers, and we're fairly confident

cylinder will maintain its pressure.

Light is another obvious issue.

There's not much sunlight, even if you travel even just a few days away from

sun. So we're going to need some artificial lighting. But that's not as

problem as you might think.

We could run a rod down the center of the ship, which would be like the sun,

according to a daily cycle, because humans and plants and other animals rely

the cycles of day and night for their rhythms of life, for their survival.

Who gets to go, to me, is the big question.

How do we select the people who get to go on the escape trip, if you will?

One of the first things that we would want to do is screen the DNA of as many

people as possible.

We would like to ideally collect this from all over the planet, from the

population, if it was feasible.

You're looking at, essentially,

a founding group of people, human beings, on some distant planet.

So the first thing you really want to consider is their survivability, which a

genetic profile will at least give you a clue to.

The people that survive are going to have to be kind of biologically perfect

a way, as perfect as they could be, because we're talking about survival

long period of time.

In some places, you would need trained medical personnel to collect the samples

and do the screening. But in other cases, people might be able to send in

materials themselves.

We could create an evacuation eligibility kit and mail it to as many

possible.

It would be a simple kit with a pin or swab stick, an instruction card, and a

return envelope.

And they all get shipped back to Starship City.

Genetics aren't the only criteria for getting into this group.

There are certain skill sets that will be required.

First of all, you need a crew to fly the ship and to maintain all of its various

subsystems. Doctors, engineers, pilots, scientists, medical technicians,

medical researchers, although we'll probably make those determinations

down the road.

No matter what criteria is selected, once you start deciding who gets to go,

you're deciding who doesn't go. And that is a lot of people.

In fact, it's 99 % of the people who are not going to get to go.

Wealthy elites would largely shape the priorities in this endeavor and would be

involved very closely in selecting who would be the group of survivors that

would actually make it into space.

There are going to be lots of nations, lots of countries around the world with

very few people selected to go on this journey.

There will be populations of people who are already resource poor who will want

to be part of this project but won't be selected.

And the struggle for resources is usually a violent one.

There's a lot of room for tragedy.

You could just have a simple lottery in which anyone had an equal chance of

getting into that. But it would be extremely messy, and wars could well

out over who would get on that ship.

Regimes might say, like, you know what? I have a nuclear bomb. If you don't do

as I say, the world is going to end. The times are ending. It's time to move on

and do it now.

So you have two different scenarios. One that, you know, people are going to get

together and have the best of humanity.

On the other hand, it might be the worst of humanity.

Once we know that our system is doomed, we have to begin looking for other solar

systems with planets that could support it.

We believe there must be other planets out there like ours.

This was something that was only a philosophical statement 20 years ago.

Now we suspect that there are many places like the Earth out there.

The only question is when we'll find them and how close the nearest one will

Finding another planet won't be easy, but we already have telescopes in space

looking for Earth -like planets orbiting other stars.

The most prolific one right now is the Kepler Space Telescope.

Kepler is a one -meter space telescope in an Earth -trailing orbit.

And Kepler looks at 150 ,000 stars every six seconds and looks for a tiny

drop in brightness when the planet goes in front of the star.

Every so often, by chance, a planet may pass between us and its parent star.

In doing so, it blocks a tiny bit of the light from that star.

If we monitor the star, we can actually see that change in light coming from the

star, and it tells us that there is a planet there.

Kepler now has 2 ,000 candidate planets.

It has planets that are the size of the Earth and smaller.

That's potentially a lot of new homes, but the problem is that Kepler's targets

are very far away.

Kepler targets are at distances of 1 ,000 to 1 ,500 light years, so while

is a great experiment for giving us the odds of finding something, it's not a

great experiment for finding where nearby we could go.

The real golden nugget at the end of the search, of course, is to find an Earth

-like world in what's called the Goldilocks Zone.

The Goldilocks Zone.

refers to a zone around a star where the temperature is just right for liquid

water at the surface of the planet liquid water is a critical piece of

it's an important part of the chemistry of life itself and even if we did

find a planet that was in the habitable zone of its parent star it had the right

temperature it had the right surface gravity and maybe even a thriving

there's still going to be a lot of unknowns that could kill any newcomer.

One big one, for example, is wind speed.

You know, as humans, we can barely function in 50 -mile -per -hour winds.

Some planets may have winds upwards of 200 miles per hour all the time.

We could get there and discover that the things we thought pointed towards a

nice, temperate environment are actually wrong.

Maybe it's a planet of crazy chemistry and strange volcanism that's completely

uninhabitable.

At some point, we're basically going to have to take what amounts to a massive

gamble. So that's it?

Does anybody have any reservations about recommending this? We're just going to

have to trust our instrument, trust our measurement, and just select the

location and just go.

This is the best chance.

Nothing else even comes close.

Because... In this situation, there's going to be no time to go back and forth

on our decision -making. The human race cannot die due to paralysis of analysis.

As the neutron star comes into the system, matter...

Bits of rock, asteroid, comet, you name it, in our solar system will be

attracted to that object.

But as they hit the surface of the neutron star, it's like setting off

bombs.

This object is going to begin to pump out radiation, which is going to scorch

everything in its path.

So we can find ourselves in a situation where as this neutron star approaches

us... the radiation from the neutron star would be digging through the

atmosphere and digging a hole in the atmosphere.

And if we find ourselves in this case where the beam coming from the neutron

star is sweeped by the planet Earth, God help us.

Most people think of launching a spaceship as a rocket that goes up in

and reaches orbit.

Well, for something as big as this, that's not going to work.

But luckily, there are other ways to build a spaceship.

It really makes a lot more sense to put it together in pieces and parts and

launch those into space and assemble them there.

When you get out into space where you don't have weather, You don't have the

Earth's gravity.

You don't have to put as much math and waste time designing it for two

environments, the environment for transit through the atmosphere and then

You just can concentrate on what it's going to take to keep it in space.

We probably won't be able to build the entire ship at Starship City. What we're

going to have to do is we're going to have to distribute the manufacturing all

around the world, creating what is essentially a global assembly line.

and that probably is the only chance we have of meeting our deadline.

The biggest challenge is going to be the systems engineering, putting the

logistics together and getting all the pieces to fit.

They're going to have to use different tooling and different engineering

processes, and they have to make sure that once they get into space, tab A

into part B and everything connects and works properly.

The last thing you want to do is, find out that your pieces don't fit together

properly when you get to space.

Launching the sections of this ship into space, that's the easy part. We've done

that before.

But even with the most advanced robotics that we have, assembling those things

into a starship is something that's going to require human coordination of a

huge scale.

I personally don't believe we'd be able to assemble our spaceship just totally

robotically without people.

That is absolutely gorgeous.

Zero G and I feel fine.

You can do a lot robotically, but sometimes you've just got to have a

site to make things work.

But you'll probably have to have somewhere on the craft astronauts

spacesuits 24 -7 overseeing the construction, doing repairs and

the spacecraft's coming together.

And that could be a very dangerous situation because we have space junk

around the Earth at high speed.

First pair and second pair both have successfully jettisoned the vehicle.

Everything is looking good.

These pieces are moving at orbital speeds, which is on the order of about 5

or even 7 miles a second.

And that's faster than any bullet you can fire on the ground.

And would do tremendous damage if it hit you.

Remember, this ark has to sustain the lives of every survivor in the human

So it's going to need to be supplied with everything they're going to need

decades on their journey.

Air.

Water.

Food.

If we don't have those things, we're not going to make it.

Period. But fortunately, the first two, air and water, are essentially the same

thing, scientifically speaking.

You can make oxygen easily by just putting an electrical current through

which is essentially what organisms do when they generate oxygen from

photosynthesis.

And if you have a nuclear power plant on a spaceship, you can generate

electricity for a very, very long period of time safely, and you can just

hydrolyze the water to generate oxygen.

So we can breathe and we have water. Now we have to figure out our food supply.

As mundane as it seems, we've never done anything on this scale before.

It's certainly not in space.

And every man, woman, and child on the ship, there's a chance of dying if we

don't figure it out.

You obviously can't take millions of cans of baked beans and frozen chicken

burgers all the way to the stars. That's not viable.

You will not be eating meat in space.

No steak in space.

You can have a meat -flavored material, but you will not be eating meat in

space. If you really are hungry for animal protein, you can get some good

or some roaches.

Insects have been a source of protein for humans for a long time.

The idea is that there would be some agriculture.

But who knows? Maybe we'll come to enjoy insects and that kind of thing.

We have to consider growing crops.

We certainly have to come up with new crops that are resistant to the

sources that will certainly be out there in space.

We're going to have to come up with new seeds that are impervious, perhaps, to

the microgravity environment.

Growing corn in space is not a viable option here. You're going to be growing

algae. You're going to be eating chlorella crackers, little green thin

that will taste like...

Ride spinach on a good day.

The question of diet raises the importance of bringing along a few

passengers on board. We're talking about bacteria.

It's critical that we would take a complement of microbes into space. It's

absolutely essential for the survival of human life.

Six pounds of a typical human adult's weight is microorganisms.

Without bacteria, we wouldn't even be able to perform simple functions like

digesting our food.

Those organisms all evolved more than 2 .5 billion years ago on this planet.

They are the ones that made the planet habitable for all the other creatures on

it.

To take bacteria in space is quite easy, actually. You can take bacteria in

very, very small vials, and they're stored in liquid nitrogen or some other

very, very cold fluid.

It's just like storing sperm in a sperm bank.

The thing you have to remember is that all of these programs have to take place

at the same time.

Building the ship...

selecting a destination, solving supply problems, figuring out how to feed the

evacuees. It all has to be simultaneously coordinated, or it's not

done. The neutron star isn't going to give us an extension.

We've got our tens of thousands of individuals, and we've got their food

water and air to breathe.

At this point, I think we would definitely want to board our craft.

We're going to want to leave the planet.

It'll be an interesting challenge to keep the passengers and crew positive,

especially in the early going.

The people that start off on the mission, possibly they're going to

depression because their realization that their home world has been

There will be friends, loved ones, places left behind, never to be seen

and that's got to hurt everyone.

We're so lucky to be one of the few thousand intact families going.

How could we not do it? It's the only choice we have.

For the first time, humans will be leaving their home.

They'll be traveling for 60, 80, 100 years perhaps in a large vessel with a

quarter million people aboard.

They've left behind perhaps family members.

They've left behind...

places they grew up. I think it's very important that we maintain a family

structure during this journey, that we allow individuals to form a home, if you

will.

If we pull it off, the Ark ship is going to be a wonder unlike anything humans

have ever created.

The last wonder we'll ever create on Earth.

We're under the assumption that people are going to behave.

But we have to be certain that we have some laws, that we have some rules, that

we have a structure.

I think what worries me the most is just the social cohesion of the group.

Will they stay on task or will they rebel and try to do something different?

turn the ship around, to give up, keeping people directed towards their

that time, not breaking up into factions on board the ship, not killing each

other. The same problem we have.

in a city or in adjacent countries. That's what we've got to master.

Clearly, we will have individuals from multiple countries who just say that the

hatred and the problems that we have here on Earth will not befall us on this

journey.

The obvious thing you need is governance.

What's the laws that you take with you? Is it the Constitution of the United

States? Is it the United Nations?

What kind of political structure do you have on board?

Do you want a democracy?

And this is a really interesting question, because you certainly don't

dictator who's going to just rule everyone, and he gets there, and he's

be the ruler of the planet and never step down. But at the same time, you

some kind of military structure that makes sure the orders are executed,

the people in charge are making very hard decisions in a military -like way,

if there was a democracy, perhaps they would be outvoted as being the person

that makes the decisions, and this can actually affect the success of the

mission.

As the neutron star approaches the Earth, there are two things that are

happen. The internal core and the crust of the Earth would start to get heated

up, and it would start to become molten, and this would result in earthquakes on

a scale that we've never seen.

What will happen next is the neutron star's gravitational field will begin to

tear away our planet.

Once the Earth's atmosphere, the Earth's oceans, and the Earth's crust start to

become perturbed, it's going to kill people pretty quickly.

Then I think the Earth's crust will shatter. The hot interior of the planet

essentially spill out into the vacuum of space.

By the time the neutron star literally rips the Earth to pieces, everybody on

the Earth is already going to be dead from radiation or volcanism or any

of other things.

So there won't be anybody there to witness this event, except for the

course, on the Earth.

The material of a shredded Earth can do a couple of things. It may fall straight

onto the neutron star and result in colossal explosions.

It's also possible that it would enter into an orbit around the neutron star as

a ring.

So, in fact, our planet could become a ring system.

Who's going to be there when we arrive?

The human life expectancy currently is about 70 years.

So by the time we reach the distant planet that is our target, chances are

of the original people who got on the Ark ship aren't going to be around.

Clearly those who were in their 50s and 60s when the journey began won't make

it. Most likely to be the younger children.

You can imagine that being a very emotional experience.

Because they know they've reached the end of their long journey and they were

successful. But in some ways, they've only started it.

Imagine the flood of emotions that these people are going to feel the first time

they see the surface of this planet.

But now they're tasked with doing something that's even more immense. Now

have to go down to this planet and rebuild human civilization on a new

A lot of people would say that thinking about building an interstellar arc and

evacuating the planet is kind of a waste of time.

I'm not sure that it's something we want to put a lot of effort into without a

threat, but it's certainly something we need to be thinking about because

sometime in the future it's inevitable that we're going to want to leave the

planet, hopefully without being forced to by a catastrophe.

This is a crazy thing to think about.

It seems like science fiction.

The end of the world.

no going back, we have to escape, we have to evacuate Earth. But it's really

impossible to say that it will never happen. And it's also interesting to

about because it's a question of whether we as a species will ever expand beyond

the confines of the planet that gave birth to it.

If you look at evolution on Earth, often great migrations and expansions of

particular species are initiated because of some disaster that forces that

species to move on.

We may be the same.

It may be that an event like this, as devastating as it is, is the one thing

that ensures that our species will live forever as it propagates out into the

universe.

Are recent floods a sign of worse to come?

Experts explore the terrifying consequences of rising sea levels on

populations in Evacuate Earth, next.