Through the Wormhole s04e03 Episode Script
Can We Survive The Death of the Sun?
Freeman: The sun.
Its radiant light sustains nearly all beings on earth.
Its glowing disk rises each day to give us new life and new opportunity.
But the sun also holds a dark secret.
Someday it will bathe the earth in a fiery holocaust.
Can we move to a new home in the cosmos? Or could we master the laws of nature and create a new earth, a new star, or even a new universe? Can we survive the death of the sun? Space, time, life itself.
The secrets of the cosmos lie through the wormhole.
To survive in the cosmos, we must learn to think in time scales longer than a single human life-span because the biggest threat to our existence will play out over billions of years.
Our tiny speck in the universe, planet earth, is in terrible danger because the sun, the giant ball of hot plasma that fuels life, is dying and our time here is running out.
When I was young, my mother and I moved from our rural home in sunny Mississippi to cold and crowded Chicago.
Heading to a strange, new place was unnerving, but I had no say in the matter.
We had to go, and that was that.
Will our entire civilization someday have no choice but to move to a new home? Peter schroeder is an astrophysicist whose lifelong passion to study stars, like our sun, inspired him to also move far away from home, from a small town in Germany to sunny guanajuato, Mexico.
Mexico gets a lot of sun, and already the ancient cultures, therefore, worshiped the sun as one face of their God.
And still today, you can -- you can feel the presence of the sun in this country.
The colors of the houses reflect this closeness to sunny days.
Freeman: The more he studies the sun, the more he, too, venerates its godlike power, because the same sun that makes life possible on earth could eventually fill our sky with an ocean of fire.
In about five billion years, the sun will run out of hydrogen fuel.
Then it begins to burn helium.
Its core shoots up in temperature, and our star expands.
It will swallow Mercury Torch Venus And grow perilously close to earth.
It may even swallow our planet and vaporize everything we know.
Schroeder: A colleague who was working on cosmology came up to my office, and he said, "I'm going to give a public talk to schoolkids, "and one of these questions is always, 'will the sun become so big that it will swallow earth?'" and I said, "oh, yeah, good point, actually.
I have to look at my latest models.
" Freeman: Peter was determined to find a definitive answer.
Even though he uses complex computer programming, the core of his model can also be built from Clay, just like the world-famous pottery of his new hometown.
To understand what's going on in the solar system, we first need a sun.
This is the earth.
Then we put it Gracias.
So, we can see it here in this orbit.
Earth is not falling to the center of the bowl because of the centrifugal forces, and it would hang out there forever unless something is changing in this balance.
Freeman: The earth stays in orbit because of a perfect balance between its speed around the sun and our star's gravity pulling it inwards.
However, as our aging sun begins to burn helium, the intense heat generated in its core blasts away some of its outer layers and causes it to lose mass.
Schroeder: And in the sun is losing and so it's losing part of its grip on earth.
Here we can demonstrate this by putting the speed up.
Okay.
So, now we see higher speed.
We will establish a larger orbit.
We thought, well, that's it.
Earth survives, and we'll be around forever.
Freeman: But Peter wondered if there was more to the story.
The sun is not a solid ball.
It is more like a mass of malleable Clay, one that can distort and bend when other bodies pull on it.
Just as the gravity of the moon pulls up a tidal bulge in the earth's liquid ocean, the earth can cause a tidal bulge in the sun's fluid plasma.
And this detail changed everything.
Well, it took a few years until I figured out a way to quantitatively take into account the tidal interaction.
And so I programmed it into my computer model, and then the answer was, "oh [Bleep.]
"Earth is plunging to the sun.
We are doomed.
" Freeman: In about five billion years, our dying sun will pull the earth into its roiling fires.
Oceans, continents, even the earth's metal core will boil away into hot plasma.
Nothing will survive.
He may be a face in the crowd today, but astrophysicist Greg laughlin could one day go down in history as the man who saved the world from a fiery death.
Some colleagues and I looked carefully at the problem.
Could you -- if you had, like, much more advanced technology than what we've got, would it be possible to save the earth? And how would you pull it off in the most elegant way? Freeman: Greg thinks he's figured out how to win back the earth from the death grip of the sun.
It's a game plan of extreme patience and even more extreme precision.
Laughlin: So, here's a model of the earth, and if this represents the earth's current position relative to the sun, as the sun expands in the sky, we're gonna need to somehow move the earth further from the sun if we want life on earth to survive.
Freeman: To move our entire planet to a cooler region of space, Greg thinks we might employ a fundamental force of nature -- gravitational attraction.
This magnet is a good model for the force of gravity because it's fairly weak.
I have to bring this magnet really close to the earth before I get any attractive effect.
Freeman: Greg's plan calls for extracting a 60-mile-wide rock from the asteroid belt and sending it on an intercept course with earth.
It would be the perfect gravitational magnet.
So, if we're gonna use the asteroid to move the earth, the gravitational pull from the asteroid is not very strong.
We've got to, every single time, come in pretty close to the earth and really pull the earth to get the earth moving so that it's at a farther orbit.
Freeman: The asteroid would fly laps around the solar system, beginning in the outer asteroid belt, swinging by earth every 10,000 years and back again.
And each time it passes, it gently pulls us a mere 30 Miles further away from the sun, keeping us at the perfect distance -- not too cold, not too hot.
But for such a high reward as saving the planet, there's an even higher risk.
As the asteroid comes in close to the earth, it's going really fast, and the absolute last thing you want to do is to hit the earth with the asteroid.
That'll cause a complete sterilization of the surface of the earth, and you've completely screwed up what you were trying to accomplish.
We have to bring the asteroid by the earth a million times.
Every single time, it has to work out perfectly.
Freeman: Each time the asteroid passes us, it must come within a mere At any point in its journey, collisions with small asteroids or space debris could slightly change its course and send it smashing into earth, annihilating all life.
The ever-present threat of sterilizing our planet makes Greg's scheme a risky last resort.
But could we survive the death throes of the sun by moving out of the way? This NASA pioneer believes we can reshape entire worlds and make the cold, red planet next door our new home.
If our home is destroyed by the sun, where will we go? There is no place like earth in our solar system, but could we take another rocky planet and transform it into a new earth? Can we build a new home for humanity? Chris McKay is known to his peers as the Indiana Jones of NASA.
But instead of a whip and a fedora, he brings more practical gear for his adventures whether in the freezing waters of Antarctica or the blistering sands of the gobi desert.
McKay: I like going out into the field and looking at the extremes of life, figuring out what it's like to live on the very edges.
It's sort of a little detective problem.
Can life survive in this environment? How does it survive? What's it doing? Freeman: Chris is now embarking on a new adventure to find out how we could survive in the extremes of a completely alien environment.
It's a quest that will take him from his home in California to an exotic greenhouse down the street.
McKay: On any world, for life to be present, there must be plants.
Plants are the basis of a biosphere.
They make the oxygen we breathe.
They make the food we eat.
How to make a world suitable for plants? The same way this structure is suitable for plants.
This is a greenhouse.
We can make a greenhouse effect on another world by putting greenhouse gases in their atmosphere.
Freeman: Chris believes that the same runaway greenhouse effect that is threatening climate stability today could be the very thing that builds us a new home when we leave earth.
What we have here is two worlds in a jar.
Think of these as little, tiny representations of an entire planet -- soil, water, atmosphere.
Just like a real planet, the sun is shining down.
So, what I have here is little carbonate tablets.
If I take these tablets, break them in half, and stick them in this bottle, one of these systems will now have more carbon dioxide than the other.
Freeman: Even though it basks in the same heat, after 30 minutes, the bottle with carbon dioxide ends up over seven degrees hotter than the bottle with just air.
That's because greenhouse gases, like carbon dioxide, retain heat from the sun.
Chris believes that the right combinations of greenhouse gases could rapidly warm the frozen wasteland next door -- Mars, a planet that will survive even after earth is burnt to a crisp.
Mars is a cold, dry place.
By the numbers, it's minus-80 fahrenheit.
atmospheric pressure, compared to 1,000 here on earth.
Its gravity is 1/3 that of earth, and its distance from the sun is All that makes it a cold, dry world, but a world that could be a warm, wet world.
Freeman: Chris estimates insulating Mars would require of greenhouse gases, way more than could reasonably be transported from earth.
But in 2008, NASA's Phoenix lander showed us where these gases could come from when it dug into and analyzed martian soil.
McKay: On Mars, we would produce super greenhouse gases out of elements that are in the soil and the atmosphere.
For example, perfluorocarbons.
These are carbon molecules attached to fluorine.
But we could go there with small factories, literally, take the fluorine out of the rocks, take the carbon out of the atmosphere, make these perfluorocarbons, and release them in the atmosphere.
Freeman: In Chris' plan to terraform Mars, a small band of mobile factories about the size of s.
U.
V.
S crawl across the surface of Mars, eating dirt and processing it into greenhouse gases.
Those gases raise the temperature of the entire planet.
Chris estimates that it may only take 100 years before humans can move to Mars, where the rain falls, water flows, and plants grow.
The first pioneers to settle Mars will need to breathe through oxygen masks, but given enough time, the martian plants will process the entire atmosphere into breathable air.
McKay: It's a long, long time before the plants make enough oxygen that it's breathable, but if that occurs, then we can walk around, in principle, just like we do on earth.
In fact, it'd be better, because with less gravity, we'd be able to jump up high.
Freeman: But escaping to Mars is only a temporary solution, because after the sun destroys earth, it burns helium for two billion years, runs out of fuel, and collapses into a tiny, dim white dwarf star.
What then? How will we power civilization in the cold darkness? A groundbreaking laboratory in California may have the answer because it could be on the brink of building an artificial sun on earth.
Humanity's days could be numbered because everything we do requires energy and almost all of our energy comes from the sun.
When our star dies, our descendants will need a new source of power.
Ed Moses is a physicist, engineer, and executive at the Lawrence livermore national laboratory in California.
His group was awarded $2 billion by the U.
S.
department of energy to build the national ignition facility, or nif.
Completed in 2009, nif is home to most powerful lasers.
They can annihilate anything locked inside this chamber.
And, yes, he's trying to take over the world.
This facility, the national ignition facility, is the world's most energetic laser by a lot.
About 100 times more than any other laser on earth.
We'd really like to find a way to make a completely sustainable, clean energy source.
Freeman: If ed succeeds, we may soon be able to power an entire city with this.
The energy in this water could power San Francisco or Washington, Boston -- cities that have like a million people in them -- for a day.
Think about the amazing part that is.
So, 365 glasses of water, you power it for a year.
It's an astounding thought.
L'Chaim.
To life.
[ Thunder crashes .]
Freeman: In the right conditions, the atoms of hydrogen in water can be fused together, converting some of their mass into pure energy.
It's the same fuel that burns inside our sun.
Inside its core, the sun's powerful gravity squeezes the nuclei of hydrogen atoms together.
As they fuse, the protons in the hydrogen nuclei convert 0.
7% of their mass into pure energy.
That may not sound like much, but it's enough to keep the temperature at 28 million degrees fahrenheit.
On earth, we don't have the prodigious gravity of the sun to create enough pressure for a fusion reaction, so Ed's team at nif will use their giant lasers.
They will charge them using a trillion watts of power from the U.
S.
electric grid.
A fraction of this power will fire the lasers.
The rest of the massive power draw will be injected into the beams along the way through a series of amplifiers.
And at the central chamber, the hypercharged laser beams will converge onto a small gold cylinder containing a single, tiny ball of frozen hydrogen.
Moses: This target is being illuminated only for a few billionths of a second, and it's being illuminated with power so intense that it's more than 1,000 times the total electrical production of the U.
S.
grid at that time.
And when we do that, we move this target, crush it together at around a million Miles an hour, and it burns for a few trillionths of a second.
Freeman: In one short burst, the hydrogen atoms will be fused into a new element, helium, and release an enormous burst of energy.
You know, our goal is interesting -- get more energy out than we put in.
You know, it sounds like the free lunch.
How do you do that? You know, right now, I have energy stored in this match as chemical energy.
So, with a small amount of energy -- just a flick of my wrist -- I can get this to burn.
Now what if I light up all these other matches? So, now, from a small flick of energy, I have this much energy.
So, I can keep doing this and make this a greater and greater conflagration, or fire.
That's the goal, what we're trying to do here -- to get a fusion burn to happen, to create the sun right here on our earth.
Freeman: If nif strikes a fusion reaction, its tiny artificial sun will produce enough energy to fire the lasers again and have plenty to spare.
A power plant built on this technology could output than is needed to fire the lasers.
Moses: This is around 10 million times more energy dense than a chemical reaction.
That's why fusion energy is so incredibly interesting.
You know, it doesn't have carbon, it doesn't use much hydrogen, it doesn't use much water, but you could power the world.
Freeman: Around the world, other fusion experiments are under way.
Even if nif is not the first to achieve ignition, someone will eventually bring star power to earth.
By unlocking the energy inside hydrogen, the most common element in the universe, our descendants will have the energy they need to keep civilization running after the sun dies.
But their entire lives would be spent under artificial light.
The last sunset would only be a fading memory.
And every time they look at the heavens, they would see billions of other worlds with stars, just like the one we once knew.
What would it take to move to a new cosmic home? With the rockets we have today, no astronaut could ever live long enough to travel to another star.
But theoretical physicists may have discovered a new means of propulsion so powerful it could take our entire civilization to any star in the galaxy.
When our sun dies, life in this solar system will change forever.
Moving billions of us to a new star trillions of Miles away seems next to impossible, but a radical idea from the frontiers of physics may show us how.
The starships that will take the human race to a new home could be powered by the most enigmatic objects in the cosmos.
[ Guitar plays .]
Shawn westmoreland is a mathematician and physicist who often does his best work when he escapes the office.
A lot of times, it's good to kind of let go of what you're working on and maybe try not to actually think about it.
If I'm stuck on a problem, I often will write a song or just play music.
Freeman: Shawn is noodling on the details of how we might trek across the stars.
It's a problem of energy efficiency.
Sending this space shuttle a mere 200 Miles above the surface of the sun burned over 4 million pounds of rocket fuel.
At that rate, sending a group of human beings trillions of Miles to another star would take more fuel than we could ever manufacture.
But Shawn knows that all matter contains significantly more energy than can be unlocked through burning, thanks to a famous equation.
This equation -- e=mc squared -- was discovered by Albert Einstein, and it tells us that everything that has mass has energy.
The amount of energy is given by the mass multiplied by the square of the speed of light.
And since the speed of light is such a fast speed, there is an enormous amount of energy contained even in a small amount of mass.
When I burn this paper I'm releasing a lot of energy.
But for this process, I'm only converting about 15 billionths of a percent of the mass into energy.
Freeman: The most efficient energy-producing process on earth will soon be hydrogen fusion, where almost is converted to energy.
But Shawn and his colleagues believe nature may already have created energy factories with much higher efficiency.
Black holes.
For a black hole, practically 100% of the mass is converted into pure energy.
Freeman: These voracious gravitational Wells devour every particle of matter or life that they touch.
But they aren't entirely black, because any mass that they swallow eventually radiates away.
Our best theory of how matter works, quantum mechanics, envisions particles as more like vibrations, and these particle vibrations can and will tunnel out of traps that are otherwise inescapable, even if that trap happens to be the event horizon of a black hole.
Freeman: The smaller the black hole, the more energetic the escaping radiation.
It's not unlike the exhaust nozzle of a jet ski that pushes water out to move the vessel forward.
If the nozzle is big, the exhaust water pushed out doesn't have much speed.
But with a small nozzle, the energy is intense enough to push the vessel forward.
[ Laughs .]
Shawn has worked out the optimum size of a spaceship-powering black hole.
Too big and there won't be enough radiation power.
Too small and it will burn out in a few seconds.
Westmoreland: We calculated that a black hole with a mass of a couple million tons seems to be a good candidate for a starship engine.
Freeman: 2 million tons is about the mass of an oil tanker.
A black hole with the same mass would fit into a space Man: Hey, Shawn.
Hey, captain Dan.
How's it going? Good.
Shawn's plan calls for tethering a tiny black hole to a spaceship.
The constant wind of radiation it generates would propel the ship forward.
Westmoreland: The best idea would be like a sailboat.
The sail is being pushed by the wind, and the black hole generates radiation, and this radiation pushes on the reflector, driving the starship forward, and it would last for about 100 years.
Freeman: If you're wondering where we might find a black hole of this size in the cosmos, Shawn is one step ahead of you.
He has worked out how we could build our own black hole.
Its size, made to order.
Westmoreland: I calculated that a perfectly efficient square solar panel in a tight, circular orbit about one million Miles above the surface of the sun would, over the course of one year, absorb enough energy to create one of these black holes.
Freeman: Shawn's solar panel would charge up high-power gamma-ray lasers and fire them at a concentrated point, producing a microscopic black hole seething with radiation, a source of fuel unlike anything mankind has ever known.
The black-hole-powered starship is a captain's ultimate delight.
It's like bringing along your own wind.
[ Guitar plays .]
Freeman: Our inefficient chemical rockets have so far only sent a small band of humans to the moon, but Shawn calculates that an array of black-hole engines could transport millions of people aboard a single ship, the constant thrust accelerating them to velocities near the speed of light.
And the passengers need not worry.
The black holes are so tiny, they pose no threat of swallowing the ship.
We might outlive the sun by moving all of humanity to a new star.
Westmoreland: Just as the explorers of previous centuries discovered new worlds, new continents, here on earth, future explorers can travel to new worlds beyond our solar system.
Freeman: If we master the power of black holes, the human race may truly become cosmic sailors, wandering from star to star.
But every star in the universe has an expiration date.
Astronomers believe that someday far into the future, every single star in the heavens will burn out.
Is this the end of humanity? Or could we build a new universe? Our sun is going to die.
So are all the other stars in the heavens.
When the cosmos goes dark, life as we know it will be impossible.
But this does not have to be the end of humanity, because we might be able to create a new universe.
Anthony aguirre is a cosmologist at the university of California at Santa Cruz, a town famous for its artists.
Staying true to the local spirit, he's exploring a unique creative process -- one that shaped our entire cosmos.
The universe is sort of everything that there is, and yet modern cosmology has suggested that maybe that's not the case -- that we understand how our universe was sort of created and has evolved.
And through that understanding, we've come to think that maybe that's a process that could happen many times, that you could create not just this universe, but other ones.
Freeman: Anthony, like most cosmologists, believes that our universe rapidly expanded into existence, creating the heavens we see today.
And he also believes that the forces of creation continue to generate a near-infinite number of other universes thanks to a cosmic mechanism called inflation.
Aguirre: So, inflation is the process where a very small region of the universe with a very, very high energy takes on the properties in which gravity actually becomes repulsive, and this antigravity force pushes the universe apart, sort of like the small piece of glass on the end of this gets blown up by a large factor into this sort of large and smooth expanse.
So, the universe, starting out rather messy and small, turns into something dramatically bigger and much smoother.
Freeman: If this is the case, the immense cosmos we see today started off as a puny speck.
In fact, Anthony's calculations suggest that the raw materials needed to trigger the creation of an entire universe could be held in your hands.
Aguirre: It turns out that the region that you need to get inflation going has a mass of only about 10 kilograms, and from that 10 kilograms, you get something that's this big, and then that expands into the entire observable universe.
So, immediately you sort of start to wonder if it just takes 10 kilograms -- it's small -- can't we just do that? Freeman: Anthony calculates that any 10-kilogram mass could inflate into a new universe, provided it is correctly compressed and heated up to Today, the hottest temperature we can reach is inside the large hadron collider in Geneva, Switzerland.
Here, tiny particles accelerate to near the speed of light and smash into one another, raising the temperature to more than 100,000 times hotter than the center of the sun.
But it's not nearly hot enough to create a new universe.
Aguirre: A collider would have to be sort of solar-system size, and we can imagine that far in the future, those colliders and accelerators and experiments will have attained the sort of energies that we need to get inflation going.
Freeman: Over the next few billion years, Anthony's spacefaring descendants will have enough time to work out the details of building the collider the size of the solar system.
If they pull it off, they could trigger an inflation reaction and create a parallel universe.
Huh? But there's just one snag.
Oh! Huh? Aguirre: Unfortunately, if we could make this baby universe, it still would be frustratingly difficult for us to actually make the transition into that other universe.
The bridge connecting our universe and the new baby universe would be both infinitesimally small and incredibly short-lived -- a tiny fraction of a second before it would pinch off.
If we tried to get to the other side, we'd almost certainly just end up in a black hole.
Of course, this black hole would be so small that we could never fit inside it, either.
But we should probably just leave it there.
[ Laughs .]
Freeman: If the only way to get to a new universe is through a tiny black hole, how would we ever move there? This scientist is working out how to pull off the greatest escape of all time.
If he succeeds, we could survive forever.
Could we ever travel to a parallel universe? A new home with new stars that will burn for eons to come could be waiting for us through a wormhole.
And one scientist is already working out how to make this fantastic voyage.
Michio kaku is a theoretical physicist and a die-hard fan of science-fiction.
His work may soon bridge the dreams of these two disciplines.
He's figuring out when we'll be able to make the journey to a new universe by quantifying how far our technology has advanced to date.
This looks like a set from a science-fiction movie, but actually it's the newtown creek wastewater treatment plant.
It's one of the largest, most modern, up-to-date waste-treatment plants on the planet earth.
Over a million people's wastewater is processed, purified, and dumped right back into the oceans.
So, in some sense, this is a monument to our technological advances.
Freeman: Today, our knowledge of science and engineering allows us to control natural resources of entire cities, and to michio, it's a sign that our civilization is climbing up the cosmic ranks.
We look at civilizations based on energy production.
A type I civilization, for example, can harness truly planetary forms of energy.
They can perhaps control the weather, perhaps control the force of earthquakes.
Eventually, you become type ii -- that is, stellar.
You play with stars, sort of like the federation of planets in "star trek.
" And then you begin to roam the galactic space lanes.
You become a galactic empire, like in "star wars.
" Now, on this cosmic scale, what are we? Do we control the weather? Do we roam the galactic space lanes? No, we're closer to type 0.
However, if you look at it very carefully, we can harness the power of entire cities and nations.
So, technically speaking, we are about a 0.
7 civilization.
Freeman: Right now, our type 0.
7 civilization can manipulate citywide natural resources, like water.
But to venture to another universe, we'll have to master the most fundamental natural resource in all creation -- the fabric of space and time.
Let's say the surface of this water represents our universe, everything we can see and touch and feel represented right here on the surface, and let's say this is us.
Notice that we are stuck on the surface of this water.
So, we cannot leave our universe.
That's us floating on the fabric of space and time.
However, there could be another universe located at the bottom of this water.
What we need is a bridge connecting two universes.
Freeman: Most physicists believe that nature allows parallel universes to exist, just like two separate planes of water.
But is there a way to connect two planes that are completely isolated from one another? Water can be distorted into a whirlpool that connects the top and the bottom.
Physicists like michio have discovered that just like a whirlpool, space itself can bend and distort to form a pathway between two parallel universes, a pathway known as a wormhole.
Now, a wormhole is a portal that allows you to go back and forth between two worlds, but they are potentially unstable.
To stabilize them, we need a new substance called negative energy.
Freeman: Just like an oil-based solution pushes apart water, negative energy would push apart space itself.
You see, this negative energy is antigravitational.
Positive energy wants to collapse the hole.
Negative energy wants to keep it afloat.
However, with enough negative energy, you may be able to go right through the wormhole.
Freeman: Our entire civilization could move from one universe to another through a wormhole, and nature may have already given us the raw materials to build one.
To actually create a wormhole, you would have to manipulate the power of a star.
For a type III civilization, it would be child's play to get a ring of white-dwarf stars.
You could create a wormhole in slow motion.
By simply increasing the velocity of the stars and the number of stars, you could slowly open up a wormhole.
This would be like the looking glass of Alice in "Alice in wonderland," and then you would add negative energy to stabilize it.
In that way, you can create a wormhole.
Freeman: In order to outlive our sun and every other star in the universe, we may someday initiate a great cycle of cosmic immortality.
New universes will be grown in laboratories, then ventured into through wormholes, a process that could repeat forever.
Today we exist at the mercy of our sun, but as we discover the true laws of the universe and learn to master them, we may, at last, find our independence.
We'll become citizens not of the earth, but of the galaxy, the cosmos, or even of the multiverse, surviving as long as our ingenuity will allow.
Its radiant light sustains nearly all beings on earth.
Its glowing disk rises each day to give us new life and new opportunity.
But the sun also holds a dark secret.
Someday it will bathe the earth in a fiery holocaust.
Can we move to a new home in the cosmos? Or could we master the laws of nature and create a new earth, a new star, or even a new universe? Can we survive the death of the sun? Space, time, life itself.
The secrets of the cosmos lie through the wormhole.
To survive in the cosmos, we must learn to think in time scales longer than a single human life-span because the biggest threat to our existence will play out over billions of years.
Our tiny speck in the universe, planet earth, is in terrible danger because the sun, the giant ball of hot plasma that fuels life, is dying and our time here is running out.
When I was young, my mother and I moved from our rural home in sunny Mississippi to cold and crowded Chicago.
Heading to a strange, new place was unnerving, but I had no say in the matter.
We had to go, and that was that.
Will our entire civilization someday have no choice but to move to a new home? Peter schroeder is an astrophysicist whose lifelong passion to study stars, like our sun, inspired him to also move far away from home, from a small town in Germany to sunny guanajuato, Mexico.
Mexico gets a lot of sun, and already the ancient cultures, therefore, worshiped the sun as one face of their God.
And still today, you can -- you can feel the presence of the sun in this country.
The colors of the houses reflect this closeness to sunny days.
Freeman: The more he studies the sun, the more he, too, venerates its godlike power, because the same sun that makes life possible on earth could eventually fill our sky with an ocean of fire.
In about five billion years, the sun will run out of hydrogen fuel.
Then it begins to burn helium.
Its core shoots up in temperature, and our star expands.
It will swallow Mercury Torch Venus And grow perilously close to earth.
It may even swallow our planet and vaporize everything we know.
Schroeder: A colleague who was working on cosmology came up to my office, and he said, "I'm going to give a public talk to schoolkids, "and one of these questions is always, 'will the sun become so big that it will swallow earth?'" and I said, "oh, yeah, good point, actually.
I have to look at my latest models.
" Freeman: Peter was determined to find a definitive answer.
Even though he uses complex computer programming, the core of his model can also be built from Clay, just like the world-famous pottery of his new hometown.
To understand what's going on in the solar system, we first need a sun.
This is the earth.
Then we put it Gracias.
So, we can see it here in this orbit.
Earth is not falling to the center of the bowl because of the centrifugal forces, and it would hang out there forever unless something is changing in this balance.
Freeman: The earth stays in orbit because of a perfect balance between its speed around the sun and our star's gravity pulling it inwards.
However, as our aging sun begins to burn helium, the intense heat generated in its core blasts away some of its outer layers and causes it to lose mass.
Schroeder: And in the sun is losing and so it's losing part of its grip on earth.
Here we can demonstrate this by putting the speed up.
Okay.
So, now we see higher speed.
We will establish a larger orbit.
We thought, well, that's it.
Earth survives, and we'll be around forever.
Freeman: But Peter wondered if there was more to the story.
The sun is not a solid ball.
It is more like a mass of malleable Clay, one that can distort and bend when other bodies pull on it.
Just as the gravity of the moon pulls up a tidal bulge in the earth's liquid ocean, the earth can cause a tidal bulge in the sun's fluid plasma.
And this detail changed everything.
Well, it took a few years until I figured out a way to quantitatively take into account the tidal interaction.
And so I programmed it into my computer model, and then the answer was, "oh [Bleep.]
"Earth is plunging to the sun.
We are doomed.
" Freeman: In about five billion years, our dying sun will pull the earth into its roiling fires.
Oceans, continents, even the earth's metal core will boil away into hot plasma.
Nothing will survive.
He may be a face in the crowd today, but astrophysicist Greg laughlin could one day go down in history as the man who saved the world from a fiery death.
Some colleagues and I looked carefully at the problem.
Could you -- if you had, like, much more advanced technology than what we've got, would it be possible to save the earth? And how would you pull it off in the most elegant way? Freeman: Greg thinks he's figured out how to win back the earth from the death grip of the sun.
It's a game plan of extreme patience and even more extreme precision.
Laughlin: So, here's a model of the earth, and if this represents the earth's current position relative to the sun, as the sun expands in the sky, we're gonna need to somehow move the earth further from the sun if we want life on earth to survive.
Freeman: To move our entire planet to a cooler region of space, Greg thinks we might employ a fundamental force of nature -- gravitational attraction.
This magnet is a good model for the force of gravity because it's fairly weak.
I have to bring this magnet really close to the earth before I get any attractive effect.
Freeman: Greg's plan calls for extracting a 60-mile-wide rock from the asteroid belt and sending it on an intercept course with earth.
It would be the perfect gravitational magnet.
So, if we're gonna use the asteroid to move the earth, the gravitational pull from the asteroid is not very strong.
We've got to, every single time, come in pretty close to the earth and really pull the earth to get the earth moving so that it's at a farther orbit.
Freeman: The asteroid would fly laps around the solar system, beginning in the outer asteroid belt, swinging by earth every 10,000 years and back again.
And each time it passes, it gently pulls us a mere 30 Miles further away from the sun, keeping us at the perfect distance -- not too cold, not too hot.
But for such a high reward as saving the planet, there's an even higher risk.
As the asteroid comes in close to the earth, it's going really fast, and the absolute last thing you want to do is to hit the earth with the asteroid.
That'll cause a complete sterilization of the surface of the earth, and you've completely screwed up what you were trying to accomplish.
We have to bring the asteroid by the earth a million times.
Every single time, it has to work out perfectly.
Freeman: Each time the asteroid passes us, it must come within a mere At any point in its journey, collisions with small asteroids or space debris could slightly change its course and send it smashing into earth, annihilating all life.
The ever-present threat of sterilizing our planet makes Greg's scheme a risky last resort.
But could we survive the death throes of the sun by moving out of the way? This NASA pioneer believes we can reshape entire worlds and make the cold, red planet next door our new home.
If our home is destroyed by the sun, where will we go? There is no place like earth in our solar system, but could we take another rocky planet and transform it into a new earth? Can we build a new home for humanity? Chris McKay is known to his peers as the Indiana Jones of NASA.
But instead of a whip and a fedora, he brings more practical gear for his adventures whether in the freezing waters of Antarctica or the blistering sands of the gobi desert.
McKay: I like going out into the field and looking at the extremes of life, figuring out what it's like to live on the very edges.
It's sort of a little detective problem.
Can life survive in this environment? How does it survive? What's it doing? Freeman: Chris is now embarking on a new adventure to find out how we could survive in the extremes of a completely alien environment.
It's a quest that will take him from his home in California to an exotic greenhouse down the street.
McKay: On any world, for life to be present, there must be plants.
Plants are the basis of a biosphere.
They make the oxygen we breathe.
They make the food we eat.
How to make a world suitable for plants? The same way this structure is suitable for plants.
This is a greenhouse.
We can make a greenhouse effect on another world by putting greenhouse gases in their atmosphere.
Freeman: Chris believes that the same runaway greenhouse effect that is threatening climate stability today could be the very thing that builds us a new home when we leave earth.
What we have here is two worlds in a jar.
Think of these as little, tiny representations of an entire planet -- soil, water, atmosphere.
Just like a real planet, the sun is shining down.
So, what I have here is little carbonate tablets.
If I take these tablets, break them in half, and stick them in this bottle, one of these systems will now have more carbon dioxide than the other.
Freeman: Even though it basks in the same heat, after 30 minutes, the bottle with carbon dioxide ends up over seven degrees hotter than the bottle with just air.
That's because greenhouse gases, like carbon dioxide, retain heat from the sun.
Chris believes that the right combinations of greenhouse gases could rapidly warm the frozen wasteland next door -- Mars, a planet that will survive even after earth is burnt to a crisp.
Mars is a cold, dry place.
By the numbers, it's minus-80 fahrenheit.
atmospheric pressure, compared to 1,000 here on earth.
Its gravity is 1/3 that of earth, and its distance from the sun is All that makes it a cold, dry world, but a world that could be a warm, wet world.
Freeman: Chris estimates insulating Mars would require of greenhouse gases, way more than could reasonably be transported from earth.
But in 2008, NASA's Phoenix lander showed us where these gases could come from when it dug into and analyzed martian soil.
McKay: On Mars, we would produce super greenhouse gases out of elements that are in the soil and the atmosphere.
For example, perfluorocarbons.
These are carbon molecules attached to fluorine.
But we could go there with small factories, literally, take the fluorine out of the rocks, take the carbon out of the atmosphere, make these perfluorocarbons, and release them in the atmosphere.
Freeman: In Chris' plan to terraform Mars, a small band of mobile factories about the size of s.
U.
V.
S crawl across the surface of Mars, eating dirt and processing it into greenhouse gases.
Those gases raise the temperature of the entire planet.
Chris estimates that it may only take 100 years before humans can move to Mars, where the rain falls, water flows, and plants grow.
The first pioneers to settle Mars will need to breathe through oxygen masks, but given enough time, the martian plants will process the entire atmosphere into breathable air.
McKay: It's a long, long time before the plants make enough oxygen that it's breathable, but if that occurs, then we can walk around, in principle, just like we do on earth.
In fact, it'd be better, because with less gravity, we'd be able to jump up high.
Freeman: But escaping to Mars is only a temporary solution, because after the sun destroys earth, it burns helium for two billion years, runs out of fuel, and collapses into a tiny, dim white dwarf star.
What then? How will we power civilization in the cold darkness? A groundbreaking laboratory in California may have the answer because it could be on the brink of building an artificial sun on earth.
Humanity's days could be numbered because everything we do requires energy and almost all of our energy comes from the sun.
When our star dies, our descendants will need a new source of power.
Ed Moses is a physicist, engineer, and executive at the Lawrence livermore national laboratory in California.
His group was awarded $2 billion by the U.
S.
department of energy to build the national ignition facility, or nif.
Completed in 2009, nif is home to most powerful lasers.
They can annihilate anything locked inside this chamber.
And, yes, he's trying to take over the world.
This facility, the national ignition facility, is the world's most energetic laser by a lot.
About 100 times more than any other laser on earth.
We'd really like to find a way to make a completely sustainable, clean energy source.
Freeman: If ed succeeds, we may soon be able to power an entire city with this.
The energy in this water could power San Francisco or Washington, Boston -- cities that have like a million people in them -- for a day.
Think about the amazing part that is.
So, 365 glasses of water, you power it for a year.
It's an astounding thought.
L'Chaim.
To life.
[ Thunder crashes .]
Freeman: In the right conditions, the atoms of hydrogen in water can be fused together, converting some of their mass into pure energy.
It's the same fuel that burns inside our sun.
Inside its core, the sun's powerful gravity squeezes the nuclei of hydrogen atoms together.
As they fuse, the protons in the hydrogen nuclei convert 0.
7% of their mass into pure energy.
That may not sound like much, but it's enough to keep the temperature at 28 million degrees fahrenheit.
On earth, we don't have the prodigious gravity of the sun to create enough pressure for a fusion reaction, so Ed's team at nif will use their giant lasers.
They will charge them using a trillion watts of power from the U.
S.
electric grid.
A fraction of this power will fire the lasers.
The rest of the massive power draw will be injected into the beams along the way through a series of amplifiers.
And at the central chamber, the hypercharged laser beams will converge onto a small gold cylinder containing a single, tiny ball of frozen hydrogen.
Moses: This target is being illuminated only for a few billionths of a second, and it's being illuminated with power so intense that it's more than 1,000 times the total electrical production of the U.
S.
grid at that time.
And when we do that, we move this target, crush it together at around a million Miles an hour, and it burns for a few trillionths of a second.
Freeman: In one short burst, the hydrogen atoms will be fused into a new element, helium, and release an enormous burst of energy.
You know, our goal is interesting -- get more energy out than we put in.
You know, it sounds like the free lunch.
How do you do that? You know, right now, I have energy stored in this match as chemical energy.
So, with a small amount of energy -- just a flick of my wrist -- I can get this to burn.
Now what if I light up all these other matches? So, now, from a small flick of energy, I have this much energy.
So, I can keep doing this and make this a greater and greater conflagration, or fire.
That's the goal, what we're trying to do here -- to get a fusion burn to happen, to create the sun right here on our earth.
Freeman: If nif strikes a fusion reaction, its tiny artificial sun will produce enough energy to fire the lasers again and have plenty to spare.
A power plant built on this technology could output than is needed to fire the lasers.
Moses: This is around 10 million times more energy dense than a chemical reaction.
That's why fusion energy is so incredibly interesting.
You know, it doesn't have carbon, it doesn't use much hydrogen, it doesn't use much water, but you could power the world.
Freeman: Around the world, other fusion experiments are under way.
Even if nif is not the first to achieve ignition, someone will eventually bring star power to earth.
By unlocking the energy inside hydrogen, the most common element in the universe, our descendants will have the energy they need to keep civilization running after the sun dies.
But their entire lives would be spent under artificial light.
The last sunset would only be a fading memory.
And every time they look at the heavens, they would see billions of other worlds with stars, just like the one we once knew.
What would it take to move to a new cosmic home? With the rockets we have today, no astronaut could ever live long enough to travel to another star.
But theoretical physicists may have discovered a new means of propulsion so powerful it could take our entire civilization to any star in the galaxy.
When our sun dies, life in this solar system will change forever.
Moving billions of us to a new star trillions of Miles away seems next to impossible, but a radical idea from the frontiers of physics may show us how.
The starships that will take the human race to a new home could be powered by the most enigmatic objects in the cosmos.
[ Guitar plays .]
Shawn westmoreland is a mathematician and physicist who often does his best work when he escapes the office.
A lot of times, it's good to kind of let go of what you're working on and maybe try not to actually think about it.
If I'm stuck on a problem, I often will write a song or just play music.
Freeman: Shawn is noodling on the details of how we might trek across the stars.
It's a problem of energy efficiency.
Sending this space shuttle a mere 200 Miles above the surface of the sun burned over 4 million pounds of rocket fuel.
At that rate, sending a group of human beings trillions of Miles to another star would take more fuel than we could ever manufacture.
But Shawn knows that all matter contains significantly more energy than can be unlocked through burning, thanks to a famous equation.
This equation -- e=mc squared -- was discovered by Albert Einstein, and it tells us that everything that has mass has energy.
The amount of energy is given by the mass multiplied by the square of the speed of light.
And since the speed of light is such a fast speed, there is an enormous amount of energy contained even in a small amount of mass.
When I burn this paper I'm releasing a lot of energy.
But for this process, I'm only converting about 15 billionths of a percent of the mass into energy.
Freeman: The most efficient energy-producing process on earth will soon be hydrogen fusion, where almost is converted to energy.
But Shawn and his colleagues believe nature may already have created energy factories with much higher efficiency.
Black holes.
For a black hole, practically 100% of the mass is converted into pure energy.
Freeman: These voracious gravitational Wells devour every particle of matter or life that they touch.
But they aren't entirely black, because any mass that they swallow eventually radiates away.
Our best theory of how matter works, quantum mechanics, envisions particles as more like vibrations, and these particle vibrations can and will tunnel out of traps that are otherwise inescapable, even if that trap happens to be the event horizon of a black hole.
Freeman: The smaller the black hole, the more energetic the escaping radiation.
It's not unlike the exhaust nozzle of a jet ski that pushes water out to move the vessel forward.
If the nozzle is big, the exhaust water pushed out doesn't have much speed.
But with a small nozzle, the energy is intense enough to push the vessel forward.
[ Laughs .]
Shawn has worked out the optimum size of a spaceship-powering black hole.
Too big and there won't be enough radiation power.
Too small and it will burn out in a few seconds.
Westmoreland: We calculated that a black hole with a mass of a couple million tons seems to be a good candidate for a starship engine.
Freeman: 2 million tons is about the mass of an oil tanker.
A black hole with the same mass would fit into a space Man: Hey, Shawn.
Hey, captain Dan.
How's it going? Good.
Shawn's plan calls for tethering a tiny black hole to a spaceship.
The constant wind of radiation it generates would propel the ship forward.
Westmoreland: The best idea would be like a sailboat.
The sail is being pushed by the wind, and the black hole generates radiation, and this radiation pushes on the reflector, driving the starship forward, and it would last for about 100 years.
Freeman: If you're wondering where we might find a black hole of this size in the cosmos, Shawn is one step ahead of you.
He has worked out how we could build our own black hole.
Its size, made to order.
Westmoreland: I calculated that a perfectly efficient square solar panel in a tight, circular orbit about one million Miles above the surface of the sun would, over the course of one year, absorb enough energy to create one of these black holes.
Freeman: Shawn's solar panel would charge up high-power gamma-ray lasers and fire them at a concentrated point, producing a microscopic black hole seething with radiation, a source of fuel unlike anything mankind has ever known.
The black-hole-powered starship is a captain's ultimate delight.
It's like bringing along your own wind.
[ Guitar plays .]
Freeman: Our inefficient chemical rockets have so far only sent a small band of humans to the moon, but Shawn calculates that an array of black-hole engines could transport millions of people aboard a single ship, the constant thrust accelerating them to velocities near the speed of light.
And the passengers need not worry.
The black holes are so tiny, they pose no threat of swallowing the ship.
We might outlive the sun by moving all of humanity to a new star.
Westmoreland: Just as the explorers of previous centuries discovered new worlds, new continents, here on earth, future explorers can travel to new worlds beyond our solar system.
Freeman: If we master the power of black holes, the human race may truly become cosmic sailors, wandering from star to star.
But every star in the universe has an expiration date.
Astronomers believe that someday far into the future, every single star in the heavens will burn out.
Is this the end of humanity? Or could we build a new universe? Our sun is going to die.
So are all the other stars in the heavens.
When the cosmos goes dark, life as we know it will be impossible.
But this does not have to be the end of humanity, because we might be able to create a new universe.
Anthony aguirre is a cosmologist at the university of California at Santa Cruz, a town famous for its artists.
Staying true to the local spirit, he's exploring a unique creative process -- one that shaped our entire cosmos.
The universe is sort of everything that there is, and yet modern cosmology has suggested that maybe that's not the case -- that we understand how our universe was sort of created and has evolved.
And through that understanding, we've come to think that maybe that's a process that could happen many times, that you could create not just this universe, but other ones.
Freeman: Anthony, like most cosmologists, believes that our universe rapidly expanded into existence, creating the heavens we see today.
And he also believes that the forces of creation continue to generate a near-infinite number of other universes thanks to a cosmic mechanism called inflation.
Aguirre: So, inflation is the process where a very small region of the universe with a very, very high energy takes on the properties in which gravity actually becomes repulsive, and this antigravity force pushes the universe apart, sort of like the small piece of glass on the end of this gets blown up by a large factor into this sort of large and smooth expanse.
So, the universe, starting out rather messy and small, turns into something dramatically bigger and much smoother.
Freeman: If this is the case, the immense cosmos we see today started off as a puny speck.
In fact, Anthony's calculations suggest that the raw materials needed to trigger the creation of an entire universe could be held in your hands.
Aguirre: It turns out that the region that you need to get inflation going has a mass of only about 10 kilograms, and from that 10 kilograms, you get something that's this big, and then that expands into the entire observable universe.
So, immediately you sort of start to wonder if it just takes 10 kilograms -- it's small -- can't we just do that? Freeman: Anthony calculates that any 10-kilogram mass could inflate into a new universe, provided it is correctly compressed and heated up to Today, the hottest temperature we can reach is inside the large hadron collider in Geneva, Switzerland.
Here, tiny particles accelerate to near the speed of light and smash into one another, raising the temperature to more than 100,000 times hotter than the center of the sun.
But it's not nearly hot enough to create a new universe.
Aguirre: A collider would have to be sort of solar-system size, and we can imagine that far in the future, those colliders and accelerators and experiments will have attained the sort of energies that we need to get inflation going.
Freeman: Over the next few billion years, Anthony's spacefaring descendants will have enough time to work out the details of building the collider the size of the solar system.
If they pull it off, they could trigger an inflation reaction and create a parallel universe.
Huh? But there's just one snag.
Oh! Huh? Aguirre: Unfortunately, if we could make this baby universe, it still would be frustratingly difficult for us to actually make the transition into that other universe.
The bridge connecting our universe and the new baby universe would be both infinitesimally small and incredibly short-lived -- a tiny fraction of a second before it would pinch off.
If we tried to get to the other side, we'd almost certainly just end up in a black hole.
Of course, this black hole would be so small that we could never fit inside it, either.
But we should probably just leave it there.
[ Laughs .]
Freeman: If the only way to get to a new universe is through a tiny black hole, how would we ever move there? This scientist is working out how to pull off the greatest escape of all time.
If he succeeds, we could survive forever.
Could we ever travel to a parallel universe? A new home with new stars that will burn for eons to come could be waiting for us through a wormhole.
And one scientist is already working out how to make this fantastic voyage.
Michio kaku is a theoretical physicist and a die-hard fan of science-fiction.
His work may soon bridge the dreams of these two disciplines.
He's figuring out when we'll be able to make the journey to a new universe by quantifying how far our technology has advanced to date.
This looks like a set from a science-fiction movie, but actually it's the newtown creek wastewater treatment plant.
It's one of the largest, most modern, up-to-date waste-treatment plants on the planet earth.
Over a million people's wastewater is processed, purified, and dumped right back into the oceans.
So, in some sense, this is a monument to our technological advances.
Freeman: Today, our knowledge of science and engineering allows us to control natural resources of entire cities, and to michio, it's a sign that our civilization is climbing up the cosmic ranks.
We look at civilizations based on energy production.
A type I civilization, for example, can harness truly planetary forms of energy.
They can perhaps control the weather, perhaps control the force of earthquakes.
Eventually, you become type ii -- that is, stellar.
You play with stars, sort of like the federation of planets in "star trek.
" And then you begin to roam the galactic space lanes.
You become a galactic empire, like in "star wars.
" Now, on this cosmic scale, what are we? Do we control the weather? Do we roam the galactic space lanes? No, we're closer to type 0.
However, if you look at it very carefully, we can harness the power of entire cities and nations.
So, technically speaking, we are about a 0.
7 civilization.
Freeman: Right now, our type 0.
7 civilization can manipulate citywide natural resources, like water.
But to venture to another universe, we'll have to master the most fundamental natural resource in all creation -- the fabric of space and time.
Let's say the surface of this water represents our universe, everything we can see and touch and feel represented right here on the surface, and let's say this is us.
Notice that we are stuck on the surface of this water.
So, we cannot leave our universe.
That's us floating on the fabric of space and time.
However, there could be another universe located at the bottom of this water.
What we need is a bridge connecting two universes.
Freeman: Most physicists believe that nature allows parallel universes to exist, just like two separate planes of water.
But is there a way to connect two planes that are completely isolated from one another? Water can be distorted into a whirlpool that connects the top and the bottom.
Physicists like michio have discovered that just like a whirlpool, space itself can bend and distort to form a pathway between two parallel universes, a pathway known as a wormhole.
Now, a wormhole is a portal that allows you to go back and forth between two worlds, but they are potentially unstable.
To stabilize them, we need a new substance called negative energy.
Freeman: Just like an oil-based solution pushes apart water, negative energy would push apart space itself.
You see, this negative energy is antigravitational.
Positive energy wants to collapse the hole.
Negative energy wants to keep it afloat.
However, with enough negative energy, you may be able to go right through the wormhole.
Freeman: Our entire civilization could move from one universe to another through a wormhole, and nature may have already given us the raw materials to build one.
To actually create a wormhole, you would have to manipulate the power of a star.
For a type III civilization, it would be child's play to get a ring of white-dwarf stars.
You could create a wormhole in slow motion.
By simply increasing the velocity of the stars and the number of stars, you could slowly open up a wormhole.
This would be like the looking glass of Alice in "Alice in wonderland," and then you would add negative energy to stabilize it.
In that way, you can create a wormhole.
Freeman: In order to outlive our sun and every other star in the universe, we may someday initiate a great cycle of cosmic immortality.
New universes will be grown in laboratories, then ventured into through wormholes, a process that could repeat forever.
Today we exist at the mercy of our sun, but as we discover the true laws of the universe and learn to master them, we may, at last, find our independence.
We'll become citizens not of the earth, but of the galaxy, the cosmos, or even of the multiverse, surviving as long as our ingenuity will allow.