- 2 days ago
Encompasses humanity's drive to find habitable exoplanets and the philosophical journey toward shifting human consciousness. Depending on your interest, it typically explores the scientific quest for cosmic twins or the spiritual principles of living harmoniously on our current home....
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00:00:01Planet Earth. Humanity's safe haven for over 200,000 years.
00:00:08But some now believe that time is coming to an end.
00:00:14Among them is the world's most famous scientist.
00:00:19I am Stephen Hawking.
00:00:22I am convinced that humans need to leave Earth
00:00:26and make a new home on another planet.
00:00:30To stay risks annihilation.
00:00:35In the last 70 years, the global population has tripled
00:00:39from two and a half to seven and a half billion.
00:00:43And our space and resources here are limited.
00:00:46Professor Hawking believes we may have to find a backup plan.
00:00:52We can, and must, use our curiosity and intelligence to look to the stars.
00:01:00We must start now.
00:01:02For humans to survive, I believe we must have the preparations in place within 100 years.
00:01:14I am Danielle George. I studied astrophysics and I am now a professor of engineering.
00:01:20And I am Christophe Galfard. I am a science writer and physicist.
00:01:25I spent over six years working alongside Stephen Hawking.
00:01:30We want to explore whether the human race can rise to Professor Hawking's challenge.
00:01:36Could we really ever find a planet and set up a new home for humanity?
00:01:41And if so, can we do it in such a short time?
00:01:46To find out, we'll be travelling the globe.
00:01:50Meeting the scientists already working on this epic challenge.
00:01:54Whoa!
00:01:55Discovering that behind closed doors, people are making amazing advances in space technology.
00:02:02And answering the big questions.
00:02:05Wow!
00:02:06So do you think that planet is the best candidate we have if we want to colonise another world?
00:02:12The answer would be yes at this moment in time.
00:02:15How will we travel the vast distances?
00:02:18And what will it take to make a new planet our home?
00:02:21Okay Jean, so we arrive on a planet with no atmosphere.
00:02:25How are you going to keep me alive?
00:02:26You might think this sounds like science fiction.
00:02:31But think again.
00:02:43Professor Hawking has good reasons for believing that humans might soon have to leave the Earth.
00:02:50As well as other population, there are countless other threats to the continued survival of our species on this planet.
00:03:00It could be an asteroid hitting the Earth.
00:03:04It could be a new virus, climate change, nuclear war, artificial intelligence gone rogue.
00:03:12Earth's history is strewn with species and civilisations that have gone extinct.
00:03:20Professor Hawking believes that if humanity is to avoid the same fate, scientists face a huge challenge.
00:03:27Is it really feasible to create a new human colony in just a hundred years?
00:03:33The first question to ask is obvious.
00:03:36Is there another planet for us to go to?
00:03:42The place to find out is here, at Paranal Observatory in the middle of Chile's Atacama Desert.
00:03:49I've been given a rare chance to see one of the world's most powerful telescopes in action.
00:03:55When I was a child, the only planets we knew about were the ones in our own solar system.
00:04:01But none of these are suitable for humans to live on.
00:04:06Now though, we're discovering that those aren't the only planets out there.
00:04:14Here at Paranal, astronomers search for new worlds outside our solar system, across the Milky Way.
00:04:23This is European Southern Observatory's aptly named Very Large Telescope, the VLT.
00:04:29And I can't deny, it's pretty massive.
00:04:32And this is where some of the world's top planet hunters hang out.
00:04:38As our own star dips down over the horizon, these incredible instruments come to life.
00:04:53The VLT is in high demand with researchers from around the world.
00:04:59Tonight, Artur Vigen and Raphael Galaché are the planet hunters.
00:05:05They're trying to determine if their current target star has a planet orbiting it.
00:05:15It looks like something's happening, so I'm going to go find out.
00:05:20So now you can see there is a star here.
00:05:22Oh, great!
00:05:23What we will want to do is to subtract all this light, which is light from the star that we
00:05:28are not really interested in.
00:05:29What we are interested in is the light of a faint planet that would be around.
00:05:34Planets orbiting other stars are known as exoplanets.
00:05:38So far, astronomers have discovered over 3,000.
00:05:42And tonight, Artur and Raphael may add to the tally.
00:05:48No, I'm not sure. I'm not convinced.
00:05:52So you think this is it?
00:05:54I think this is it.
00:05:55Yeah, it's possible.
00:05:56The team here, optimist pessimist, is it?
00:05:59I hope it's a planet.
00:06:01We'll have to re-observe that star in a few months from now.
00:06:05And if it's still moving with the star, then it means it's a planet.
00:06:09So if it turns out to be an exoplanet, do you guys get to name it?
00:06:13Yeah.
00:06:13Yeah, with a B after the name of the star.
00:06:16Excellent. And do we know what star it is?
00:06:18Yeah, we know, but we cannot tell you.
00:06:21Oh, okay.
00:06:21I mean, until it's confirmed and it's published, everything's secret.
00:06:26So is there a general consensus amongst planet hunters to how many potential exoplanets there could be?
00:06:33We are really starting to think that planets are ubiquitous in the universe.
00:06:38Really?
00:06:38That they are really everywhere.
00:06:40I mean, we've discovered the first exoplanets about 25 years ago.
00:06:45And now we are finding more and more, almost, on average, we find a few planets each day.
00:06:51A few new planets each day.
00:06:52Each day. Wow.
00:06:53So I should probably get out your way then.
00:06:55That was a hint.
00:06:56Yeah.
00:06:56Thanks, Raphael.
00:06:57Good luck, guys.
00:06:58See you later.
00:07:01The researchers at Paranal think there could be billions of potential planets in the galaxy for a new colony.
00:07:08But our criteria have to be pretty demanding.
00:07:19Humans are very fragile creatures.
00:07:23We've evolved in Earth's very specific habitat.
00:07:28Stray too far from this and we're in trouble.
00:07:32Out here in the Atacama Desert, it can get pretty hostile.
00:07:37It is one of the driest, saltiest desert on Earth.
00:07:41But compared to pretty much any other places we might land on one day, this is positively idyllic.
00:07:50So, a potential new planet has to pass some stringent tests.
00:07:56First, we need to find a planet that's rocky and about the same size and density as the Earth.
00:08:04It needs to be at the right temperature, not too hot, not too cold.
00:08:09Just right.
00:08:11That's because for us to survive on a planet, we need water.
00:08:15And that water should be liquid and on its surface.
00:08:20Too far or too close to its star and water will be ice or steam.
00:08:26Only in a narrow orbit will conditions be just right.
00:08:29What we call the Goldilocks zone.
00:08:32For our Sun, a yellow dwarf star, the Goldilocks zone stretches from roughly the orbit of Venus to the orbit
00:08:40of Mars.
00:08:42Earth sits neatly right in the middle.
00:08:54But even if we find our perfect Goldilocks planet around another star, there is one more tough criterion.
00:09:01We have to be able to reach it.
00:09:06Most of the things we can see in the night sky are a very, very long way away.
00:09:14Space is so enormous that using miles to measure it doesn't really work.
00:09:20Each light year, a better way to measure it, is around six million million miles.
00:09:30Even the brightest stars in the sky are unbelievably distant.
00:09:37Over here is the Orion constellation.
00:09:43And this is Betelgeuse, one of the biggest stars we know.
00:09:48It is nearly 500 light years away.
00:09:54It might seem hopeless to explore those stars and their planets.
00:09:58But luckily, not all the stars are quite so far away.
00:10:06Now over there is Proxima Centauri.
00:10:10After the Sun, that star is the closest to the Earth.
00:10:14Our stellar next door neighbour lies just 4.2 light years away.
00:10:19In cosmic terms, that is a tiny distance.
00:10:24For human travel, it's still a long way.
00:10:27But seems much more realistic than most others.
00:10:30A planet around Proxima Centauri might just be reachable.
00:10:36But looking with the very large telescope, we can't see one.
00:10:43Some planets are hidden from even the most powerful telescopes by the brightness of their stars.
00:10:49To look for a planet around Proxima Centauri, we'll need a different method.
00:10:56Swing ball.
00:10:57Indeed. May the best man win.
00:11:04Well, you've trained, obviously.
00:11:06We had this when I was a kid in my backyard.
00:11:10Astronomer James Jenkins uses a less traditional method to look for exoplanets.
00:11:16So tell me, what does the swing ball got to do with finding planets?
00:11:21Well, if we consider that the ball is a planet, and the post there represents our star in the centre,
00:11:29we can see that the planet orbits the star.
00:11:32And not only that, the planet exerts a gravitational force.
00:11:36It pulls the star.
00:11:38And we can see, with this analogy of the post, that there's a wobble, a movement of the star.
00:11:42And that's what we search for when we look for planets.
00:11:45Alright.
00:11:50James and his team used the telescopes in Chile to observe the Proxima Centauri star for 60 nights in a
00:11:57row.
00:11:58Each night, they measured the backwards and forwards movement of the star,
00:12:03looking for the tell-tale sign of a wobble.
00:12:08Back inside Paranel Observatory's astronomers' residence.
00:12:12And yes, that is the hotel from James Bond Quantum of Solace.
00:12:16James shows me what they found as the results came in.
00:12:20Each night, as this data was coming in, and we were putting those points on this plot,
00:12:25we started to see this kind of oscillation.
00:12:29And this wobble of the star that we can see here told us,
00:12:33hey, the indications we found before were correct.
00:12:36There is probably something out there.
00:12:39There is probably a planet.
00:12:41Each night, we were seeing this conformation.
00:12:43And after three weeks, we knew, pretty much for certain, Proxima b exists.
00:12:50So do you think that planet is pretty much the best candidate we have if we want to colonise another
00:12:56world?
00:12:57I would have to say the answer would be yes at this moment in time.
00:13:01Just the distance between the sun and Proxima Centauri,
00:13:06the fact that it's the nearest star to our sun,
00:13:08and it has this planet that could be Earth-like.
00:13:12If in the future that we can build craft that can travel between the stars,
00:13:17I think that Proxima b would be basically the first stop on that journey.
00:13:21That's the best thing I've had for a long while.
00:13:24I'm glad to hear that.
00:13:25That's very good news.
00:13:28Thanks to James and his team's remarkable discovery,
00:13:31we now know that amazingly there is a planet in our neighbourhood
00:13:35that could be suitable for colonisation.
00:13:40Welcome to Proxima b.
00:13:45From our observations, we know it's a little more massive than the Earth.
00:13:51and it's almost certainly a rocky planet.
00:13:56Its year, the time it takes to orbit its star, is just 11.2 days.
00:14:03That means Proxima b must be very close to its star.
00:14:09But because its star is a red dwarf, much smaller and cooler than our sun,
00:14:14this planet does sit in the Goldilocks zone.
00:14:22And there might just be liquid water at the surface.
00:14:29This planet could be our best destination for humankind's new home.
00:14:34And it's our near neighbour.
00:14:38But Proxima b is still not that near.
00:14:424.2 light-years is a staggering 25 million million miles.
00:14:48Far beyond anything we've reached with the spacecraft before.
00:15:03Since humans first ventured into space, we've been using basically the same technology.
00:15:18Space rockets burn chemical fuel.
00:15:21This produces gas, which pushes them through space.
00:15:26The hotter the gas, the faster the rocket travels.
00:15:31But gas can only get hot enough for the rockets to reach about 24,000 miles an hour.
00:15:38Pretty quick, but not quick enough for our trip.
00:15:44One of these rockets would take 120,000 years to get to Proxima b.
00:15:50To reach our new planet within Professor Hawking's timeframe, we're going to need a huge technological leap.
00:16:01This is an enormous challenge.
00:16:04We have lost the momentum of the space race, that was driven by the Cold War.
00:16:12We need to start again.
00:16:14It isn't impossible.
00:16:17To leave Earth will take a global approach, everyone should join in.
00:16:24Our best minds need to focus, and rekindle the romance, and the exploratory spirit of space travel, found in the
00:16:33early lunar expeditions.
00:16:34We have lost the distance.
00:16:40Incredibly, here in Texas, one of those great minds is already working on this challenge.
00:16:47Franklin Cheng Diaz is a rocket scientist and former astronaut.
00:16:53Is that you?
00:16:54That's me.
00:16:54On the first spacewalk, we were doing some construction job on the International Space Station.
00:17:02Franklin has built a revolutionary rocket engine in his workshop, that's powered not by traditional rocket propellant, but by plasma.
00:17:13Plasma is a state of matter, formed when a gas is given so much energy that its atoms are transformed
00:17:20into a stream of charged particles.
00:17:23Lightning is one example.
00:17:26Because plasma can be so much hotter than the gas produced by a chemical rocket, it could push a spacecraft
00:17:33much faster.
00:17:37Here it is.
00:17:38There we go.
00:17:39Wow.
00:17:41Nice.
00:17:42So this is the vacuum chamber, and the rocket is inside.
00:17:46So you're creating the vacuum of space in there.
00:17:48Absolutely, that's the point.
00:17:51Using plasma in an engine like this could change the way we travel in space forever.
00:17:58How does the engine actually work?
00:18:00The way you make the plasma is you start out with gas, and it goes into a cavity.
00:18:06In that cavity there is an antenna.
00:18:09And that antenna shines radio waves into the cavity.
00:18:13Okay.
00:18:14And the gas becomes a plasma.
00:18:17Okay.
00:18:17Which is about maybe three to five million degrees.
00:18:21Now you're talking hot.
00:18:23Now you're talking hot.
00:18:24And then you just let it go.
00:18:26And that makes a heck of a rocket.
00:18:30The magnetic field inside the chamber directs the charged plasma cloud and forces it into a nozzle shape to create
00:18:38a powerful jet.
00:18:41Can we see it in action?
00:18:43We can certainly do.
00:18:44We can certainly see it in action.
00:18:48So that's the back of the rocket.
00:18:50This is the piston sand.
00:18:52Okay.
00:18:54Okay, here it comes.
00:18:59This superheated jet, thousands of times hotter than conventional rocket exhaust, is what provides the engine's thrust.
00:19:07So with this kind of thrust, how fast can a rocket go?
00:19:10You can go about ten times faster than a conventional rocket.
00:19:13And that will get us to Mars in as low as 39 days.
00:19:18That's essentially the plan.
00:19:20And why is this better than a conventional rocket, the ones we use today?
00:19:26The simple answer is that it's more efficient and requires less fuel.
00:19:32Working with NASA, Franklin is close to trying out his plasma rocket in space, where he predicts it could reach
00:19:39speeds of over 100,000 miles per hour.
00:19:44If it works, it could completely transform space travel.
00:19:48That's right.
00:19:50We want to be able to put out this rocket in service in a matter of three years from now.
00:19:56So do you think this will revolutionize space travel, at least maybe in the solar system?
00:20:02I think so. We want to completely do a paradigm shift in the transportation arena in space.
00:20:09So, Franklin, could your rocket take us to Proxima B, for instance?
00:20:14Wow, that's a long way. This rocket as it is known. The way I think of it is more like
00:20:20a precursor to the rocket that could take you to Proxima B.
00:20:27Though Franklin is confident that future generations of his plasma rocket will be able to take us to an exoplanet,
00:20:34for now his focus is on travel within the solar system.
00:20:39This rocket might reach Mars in 39 days, but it would still take 2,000 years to get to Proxima
00:20:47B.
00:20:48If we want to make it within Professor Hawking's timeframe, we need technology that's even faster.
00:20:58Amazingly, there might be a way. And it's staring us right in the face.
00:21:09In California, a team led by astrophysicist Philip Lubin is investigating an alternative propulsion method.
00:21:18They think they can get a spacecraft to Proxima B in just 20 years, powered only by light.
00:21:25We can demonstrate that light carries momentum and energy very easily.
00:21:30If you take the torch here and shine it at these small veins, you can see that it'll begin to
00:21:37push the veins around.
00:21:38And that's just the light doing that?
00:21:40Yeah, the light itself transfers momentum and energy to the vein, and that propels it away.
00:21:46Okay, but that isn't a very powerful light, and I wasn't going very fast, and that's also very small as
00:21:50well.
00:21:51Yeah, it's really a scaling problem. Increase the power level, then suddenly we have a very effective tool for propelling
00:21:57spacecraft that are suitable for interstellar flight.
00:22:04This might seem like pure science fiction, but for the last seven years, light from the sun has powered the
00:22:11Japanese spacecraft Icarus.
00:22:15This is a very real technology that works.
00:22:24Philip's master plan is to build a massive bank of lasers measuring 10 kilometers across.
00:22:31His spacecraft will unfurl a lightweight sail.
00:22:35The laser light pushes on the sail, accelerating the craft to one-fifth the speed of light.
00:22:48Philip and his team are so confident this technology will work, they've already started designing tiny unmanned space probes to
00:22:56send to Proxima B.
00:23:01Nick!
00:23:03Nick Rupert is building a fleet of spacecraft the size of a SIM card.
00:23:08Each with its own laser sail, they will fly out to the planet ahead of a human mission.
00:23:15Wow, it is small, isn't it? So this is a prototype spacecraft?
00:23:19Yes. There's capacitors right here. There's maybe 10 or so of them.
00:23:23Wow, they're tiny.
00:23:24Yes, very tiny.
00:23:25I'm having a go at assembling some of the electronics for myself.
00:23:29I'm going to choose that one.
00:23:31All you have to do is line up the capacitor.
00:23:34I always thought I had a steady hand as well.
00:23:40Okay.
00:23:41Okay, so now what you're going to do is you're going to take the hot air gun back here.
00:23:47And you're going to hold it about an inch away from the capacitor you just placed.
00:23:51And just move it back and forth slightly.
00:23:54And then it will actually solder itself down.
00:23:57So it should actually seat itself.
00:24:00Oh, yeah, wow, okay.
00:24:02You see it?
00:24:02Wowee!
00:24:03Yeah, it pulls itself right into place and lines up.
00:24:06Wowee, that's like magic.
00:24:08That's definitely the neatest that I've ever soldered.
00:24:15This is a fully functional spacecraft, armed with sensors, cameras, and even tiny rockets to help it maneuver.
00:24:24Initially what will happen is it will fly sort of edge on.
00:24:28And once you get to Proxima B, it will then flip up and its sensors will take all of their
00:24:33data,
00:24:34all of their information, whether that be a camera, temperature, sensors,
00:24:38and then it will actually flip around and send that data back.
00:24:41So effectively they could do like a flyby type thing of Proxima B.
00:24:45And the idea would be you would have hundreds of these at a time.
00:24:49You sort of make a mosaic of all these individual data points and you use that to paint sort of
00:24:53a much bigger picture of what you're looking at.
00:24:57Nick hopes to have these probes in operation within the next 30 years.
00:25:03It's incredible to think vessels like these, powered solely by light, may be the first to glimpse the surface of
00:25:10Proxima B.
00:25:11Giving us incredible insight into what this planet is really like.
00:25:18But these are just tiny unmanned spacecraft.
00:25:22Does Philip think we could use the same light propulsion technology on a craft that's big enough to carry people?
00:25:28What I hadn't quite appreciated before today was how far along that technology roadmap you were.
00:25:36But can you scale that up? Can you use the same technology to have humans to travel interstellar?
00:25:41There are many hard problems in this project. It's not a simple project.
00:25:45It's not easy and it's not cheap.
00:25:47But there's no fundamental reason why we couldn't build extremely large systems which would be capable of propelling humans to
00:25:54intergalactic distances.
00:25:55It's going to be fundamental transformation in human exploration.
00:26:02Building a laser propulsion system that's big enough to transport humans does present us with challenges we're yet to solve.
00:26:10But this is a proven technology, and if we can succeed in scaling it up, it could reduce the travelling
00:26:17time to Proxima B from 2000 years to just 20.
00:26:22Well within Professor Hawking's 100 year deadline.
00:26:28I have no doubt that we will eventually find ways of crossing the immense distances of space in just a
00:26:36few years.
00:26:38One of our species' great strengths is embracing new ideas and evolving them into cutting edge technologies.
00:26:47Just look at advances we've made in the fields of medicine, communications, and electronics.
00:26:55We built the first silicon chip only 60 years ago.
00:27:00Now it powers just about every aspect of our lives.
00:27:05Our ingenuity will get us to Proxima B.
00:27:10We now know what planet we're heading for, and have seen technologies which could propel a spacecraft on the journey
00:27:16to Proxima B.
00:27:18But the people on board will be tested in ways we can hardly imagine.
00:27:23Now we need to find out what sort of people could rise to this challenge.
00:27:30Okay, you cover it open, you can lift the airlock if you want.
00:27:36All right. All right, you're ready to roll. Let's go buddy.
00:27:42The International Space Station orbits the planet every 90 minutes.
00:27:49Today, it is the only place you find humans living in space.
00:27:55The current generation of astronauts have never been asked to leave the proximity of Mother Earth.
00:28:02But they have a unique perspective on the hardships that would be endured on an interplanetary journey.
00:28:09One of them is my fellow countryman, Thomas Pesquet.
00:28:13And I have arranged a live conversation with him while he's circling the Earth.
00:28:20Hello.
00:28:21Hello.
00:28:23Hi Jules.
00:28:24Hi.
00:28:24How are you?
00:28:25Good. Good job. Thank you.
00:28:27Thomas knows a thing or two about what it's like to be stuck in a tin can for long periods.
00:28:33He's been crewing the space station for the last six months.
00:28:37I want to know his perspective on the pressures and interplanetary journey we'd put on the human psyche.
00:28:44Station, this is Houston. Are you ready for the event?
00:28:48Station, yes, we're ready for the event.
00:28:5030 seconds.
00:28:51I can see that he's tidied up his room, which is another.
00:28:5710 seconds.
00:28:59European Space Agency, this is Mission Control Houston. Please call Station for a voice check.
00:29:04Station, this is Jules from ESA PAO here in Cologne.
00:29:08How do you hear me?
00:29:105x5, how me?
00:29:14Hello Thomas. Very, very honoured to be speaking with you.
00:29:19Pleasure for you too.
00:29:21I begin by asking Thomas about the challenges of living on board a spaceship.
00:29:27Like outdoor sports and activities.
00:29:29And of course here in the ISS, the chances to go out are very few and in between, and far
00:29:36in between.
00:29:37But yeah, I'm missing the freedom to go wherever I want, whenever I want, because it's a confined space.
00:29:44But obviously it's one of the challenges of the job and we all accept it.
00:29:50But how much worse would it be to undertake an interplanetary journey?
00:29:55What big problems do you think we would have to overcome, maybe psychologically, to get to another planet?
00:30:03I think we're going to completely lose sight of the Earth.
00:30:05We're going to be alone in empty space, surrounded by blackness.
00:30:09Thank God on the International Space Station, we're still connected.
00:30:13We have a way to call on the phone, we have a way to exchange emails.
00:30:17Even though it's rather limited, it's better than nothing.
00:30:21In a longer, deeper space journey, it will be more challenging.
00:30:24Time delay in the communications makes direct communication almost impossible.
00:30:29We'll have to find the right people for this.
00:30:31We'll have to keep them busy because when you have a lot to do, then you don't have time to
00:30:35think about it.
00:30:36You don't have time to think about the danger.
00:30:37You don't have time to think about the consequences.
00:30:39You don't have time to think too much, to second guess yourself sometimes.
00:30:44So we need to find a way to keep people busy all the time and then the trip is going
00:30:48to be okay, I think.
00:30:50Would you volunteer for such a journey?
00:30:53To Mars and even another planet?
00:30:57Yeah, absolutely.
00:30:59I'd like to think of the astronaut corps as modern explorers.
00:31:04I think it's in our DNA as human beings and especially as astronauts.
00:31:10So if one day we're asked to volunteer for such a trip, I'll raise my hand.
00:31:14But I know I won't be the only one, so then I have to choose which way is more worthy
00:31:19of the trip.
00:31:21It's absolutely incredible to be able to speak with you.
00:31:23Thank you so much for your time and for the work you're doing.
00:31:27You're welcome. It was a pleasure to have you on board the ISS.
00:31:32Our interplanetary mission to Proxima B will require many astronauts like Thomas.
00:31:40For those chosen, it's going to be a huge emotional challenge.
00:31:45And I've been wondering, do I have what it takes to join them?
00:31:51I've decided to ask the experts.
00:31:55If we want to understand who to select to found a colony on a new planet, where better to come
00:32:02than the place they've been selecting and training astronauts for decades?
00:32:10So this is the US laboratory module, and this is our galley table, where our crew would gather for dinner
00:32:16every night.
00:32:16Here at NASA's Johnson Space Center, astronaut Mike Barrett is giving me a tour of the International Space Station mock
00:32:23-up, where he and the other astronauts train.
00:32:27It's a bilingual station. Everybody has to be proficient in English and Russian.
00:32:32And Russian?
00:32:32Yep. So for us, it's hard enough to learn Russian. For the Russians, they have to learn English.
00:32:37But interestingly, if you're Japanese, you still have to learn Russian and English.
00:32:41Mike has done two long-duration trips to the ISS, and spent 212 days in space.
00:32:48All right, let's take a look at the Orion.
00:32:51Wow. Okay.
00:32:52With a future NASA Mars mission on the cards, Mike has already put some thought into what will be needed
00:32:58in interplanetary astronauts.
00:33:00We look at Mars now as the next destination, as something that's remote and difficult to do.
00:33:05But in the long run, Mars will be an inner waypoint.
00:33:08It will be an inner outpost from which we will continue to branch out.
00:33:12And when you look at how people have moved across our planet from, say, Europe to the Western world, you
00:33:18first have the explorers.
00:33:20And they're the ones who see things for the first time and characterize what the environment is like, the risk,
00:33:25if you will.
00:33:26And if it looks like a good place to go, you're followed by the pioneers, the people who learn to
00:33:32live there.
00:33:33And typically, pioneering is also fairly austere.
00:33:35But you go there with a certain knowledge and a certain resolve that you're there to stay.
00:33:41The pioneers are then followed by the colonists, if you will.
00:33:45The colonists bring what I would call a snapshot of humanity, of civilization, to occupy that spot.
00:33:52And so we really acquire that destination and make it our own.
00:33:56So someone sitting at home on the sofa now could be an astronaut in a few generations' time colonizing their
00:34:02planet.
00:34:03Absolutely.
00:34:03I mean, we look forward to a continual expansion of civilization.
00:34:07So this cycle will repeat over and over as we keep pushing the boundaries.
00:34:12We will start again with the explorers and the pioneers and the colonists who will eventually follow.
00:34:16So do I have what NASA are looking for in an interplanetary explorer?
00:34:21It's time to pop the question.
00:34:24I had a look on your website and the application form for if you want to be an astronaut was
00:34:28there.
00:34:29So I filled it out to take a look at it because I'm an engineer.
00:34:35Yeah.
00:34:36And so I was sort of thinking, oh, well, you know, maybe.
00:34:39Well, you've got to play to win.
00:34:41So let's see what you got here.
00:34:42All right.
00:34:44A very distinguished scientist in your field and an extremely impressive list of awards and honors.
00:34:52However, what we like to see also is something beyond the laboratory.
00:34:56It shows that you can be comfortable in an uncomfortable place.
00:35:00Spaceflight is still a very austere, extreme environment, and we're not much into creature comforts.
00:35:07So we look for people who've had expeditionary experience.
00:35:10We definitely look for people who want to explore and have the commitment to leave your home planet and go
00:35:18make another planet your own.
00:35:27I want to see if I have that courage and commitment myself.
00:35:31So I've signed up for an extreme adventure down here on Earth.
00:35:46This is Finse in central Norway.
00:35:50For over 100 years, intrepid adventurers, including Scott, Amundsen and Shackleton, have used this desolate landscape as a training ground.
00:36:02Today, polar explorer Anne Daniels is here preparing for an expedition to the North Pole.
00:36:10Anne pushes herself to the limits to explore uncharted places.
00:36:14And I want to find out what that feels like.
00:36:19She's taking me into the extreme wilderness to give me a sense of what exploration is really like.
00:36:25If it's not good for your mission, and it doesn't get you anywhere, you don't take it.
00:36:34Just like the pioneers of the early polar expeditions, the humans who voyage to another planet will be venturing into
00:36:41the complete unknown.
00:36:59Do you get a bit sort of sick of white when you're out here?
00:37:02No.
00:37:03Look around, there's different shades of white.
00:37:06It's beautiful.
00:37:07But when you get back to civilisation, that's when the colours just hit you and you kind of...
00:37:19Whilst astronauts on the space station are able to look down on the Earth, our crew will have years of
00:37:26travel through continual blackness.
00:37:31They will be the first generation who will lose sight of the Earth forever.
00:37:39OK, just here.
00:37:49Gather round the flames.
00:37:52That's better.
00:37:53Oh, there we go.
00:37:55This is the most remote place I've ever been in my life.
00:38:00And the temperature's now minus 18 degrees.
00:38:05It makes me wonder, what drives a pioneer to go to places where no one else has been?
00:38:14Being here with you today has really pushed me to my limits.
00:38:17What drives you to do what you do?
00:38:19Why wouldn't I do something so great and different?
00:38:25Because you've got a family, and this is really dangerous, right?
00:38:28I mean, you might die.
00:38:29For any expedition you do, you could die, couldn't you?
00:38:32I could.
00:38:33I became an expert at the ice.
00:38:35And I kind of think the children are a barometer to me, because I have to come back.
00:38:40If I was going to cross an area of thin ice, I would look and think, can I cross it?
00:38:47Can I face my kids if I try and cross this?
00:38:51And if it was, yeah, then I would.
00:38:53So I think they kind of keep me safe.
00:38:55So our space explorers would probably need the same thing.
00:38:59If you're helping the world you live in, which, let's be honest, that in space they really
00:39:04are understanding new things, then it also makes you keep going, because you know it's
00:39:09the bigger picture.
00:39:13Anne's outlook really defines the spirit of the explorer.
00:39:19But it's given me pause for thought about my own attitudes.
00:39:28It's almost inconceivable to think that somewhere out there, one day, humans will be living.
00:39:38I have a two-year-old daughter.
00:39:40Could I leave her indefinitely?
00:39:43Could I leave her on a quest where I may never come back?
00:39:48Where all she'd be is a memory and a photograph on a logbook to me?
00:39:53No, I really don't think I could.
00:39:57So this journey is really telling me a lot about the type of person our space explorers
00:40:02have to be and the sacrifices I think they're going to have to make.
00:40:06I might not be the right person to make that one-way trip to a new world.
00:40:13But for Professor Hawking, there's no doubt that as a species, humans have got what it takes.
00:40:20We are the first species in history that has the potential to escape Earth.
00:40:27We are the only ones driven by curiosity.
00:40:33Transcending our apparent limits is what makes humans unique.
00:40:38I am living proof of that.
00:40:42I lost my voice, but can still speak using my voice synthesizer.
00:40:49Gravity pins us to the ground, but I have taken a ride on a zero-gravity flight.
00:40:59In Professor Hawking's view, with our adventurous spirit and a little help from technology,
00:41:06humans are capable of almost anything.
00:41:09A journey to Proxima B is within our reach.
00:41:16So how many of these adventurous humans will ultimately make this extraordinary journey?
00:41:23Once our astronauts have arrived, they'll soon have to breed to create a new human population
00:41:29that can thrive for generations to come.
00:41:36The answer to how many we need to create that could be here at Washington's Smithsonian Zoo.
00:41:43Here they study not human populations, but endangered species.
00:41:48These are golden lion tamarins.
00:41:51Just 40 years ago, they were on the brink of extinction.
00:41:55Population geneticist Dr Brandy Smith was part of the team behind the golden lion tamarins
00:42:01impressive comeback.
00:42:02Oh yeah, he did it for a while too.
00:42:06So why did they nearly become extinct, Brandy?
00:42:09Oh, you know, they live in the same places that humans like to live.
00:42:12And so their habitat just began to decrease and become fragmented.
00:42:18And the tamarins just couldn't keep up.
00:42:20So there were only about 200 left in the wild.
00:42:23I have another one.
00:42:24And they were on the edge of extinction.
00:42:25They were critically endangered.
00:42:27And when populations get that low, you become concerned because essentially they start to lose genetic variability
00:42:34and a climate change came through or a disease.
00:42:37The populations can be wiped out because they don't adapt to changing conditions.
00:42:42The tamarins had a close shave.
00:42:45Using a controlled breeding program, Brandy and her team rescued this population
00:42:51and they are now off the endangered list.
00:42:54Are you in a grape?
00:42:55It's a big grape.
00:42:57But that's a stark reminder for our human colony.
00:43:01If there's not enough genetic variation amongst the group we send, our population could easily go extinct.
00:43:08So perhaps then we should be handpicking our best genetic specimens to represent the human species.
00:43:16Could we choose the individuals genetically to make sure that we had all of the right things we needed once
00:43:22we got to the planet?
00:43:23Well, the problem is you don't know which genes to select.
00:43:27So the ones that might confer an advantage here on Earth might be totally, totally different if we went to
00:43:34another planet.
00:43:35They might not be the best and they could also be detrimental.
00:43:38So as a population geneticist, what's your professional opinion on how we should address this challenge?
00:43:44You need to collect a sample that's large enough to get a good representation.
00:43:49You don't want to select. You want it to be a random population.
00:43:55This means that to succeed in colonizing a planet like Proxima b, we must take potentially thousands of astronauts.
00:44:03And all of them will need to spend decades traveling through the hostile environment of space.
00:44:11Protecting their bodies will be a huge challenge.
00:44:18We didn't evolve for the alien environment of space and its effects could be lethal.
00:44:24Even just a few months on the International Space Station has extreme effects on the astronauts who go there.
00:44:31And I'm going to see them for myself.
00:44:35I've been granted exclusive access to a NASA medical test.
00:44:40I'm very excited about this.
00:44:43NASA don't normally let cameras see astronauts at this stage of their mission.
00:44:48But over there is Kate Rubins.
00:44:52She's recently come back from a 115-day mission on the ISS.
00:45:01Astronaut Mike Barrett is also a doctor and a leading expert in space medicine.
00:45:07The human body changes almost globally when you put it in weightlessness.
00:45:12From the standpoint of fitness, we do lose bone and muscle because we don't have that normal daily challenge of
00:45:17gravity.
00:45:18But we also lose blood volume.
00:45:21So that makes you really good for weightlessness.
00:45:23As it turns out, it's very adaptive, if you will.
00:45:26But when you want to come back to Earth, it becomes maladaptive.
00:45:33Visitors to the ISS do intense exercise regimes to build up muscle, but it isn't enough to combat the lack
00:45:40of gravity.
00:45:42Standing by for touchdown.
00:45:44By the time they return to Earth, astronauts are fragile and at risk of injury.
00:45:49Flashing that familiar smile, Kate Rubins now out of the Soyuz spacecraft.
00:45:55Kate, welcome back. You're looking good.
00:45:58Landing on a planet in this state, people would struggle to build anything, let alone a new civilization.
00:46:04And muscle wastage isn't the only problem.
00:46:09The lack of gravity also disrupts our sense of balance.
00:46:14The day they return to Earth, some astronauts have the coordination of a toddler.
00:46:21I'll put one here.
00:46:22Even though she spent just 115 days in space, five months after her landing, Kate is still recovering.
00:46:30Setting up a course for an astronaut.
00:46:32We've all been carefully measured out, right?
00:46:34All right.
00:46:35Whenever you're ready and you go, I'm going to hit the start button.
00:46:42So this actually gives us a better reflection of what a person is capable of in the post-flight period.
00:46:47Sprint, sprint, sprint, sprint, sprint.
00:46:52It's muscular power, it's speed, agility, it's balance.
00:46:57Does it feel weird when you're doing it? You're like, man, this should be really, really easy.
00:47:00Try doing it on the deck of a moving ship. That's about what it feels like when we're landed.
00:47:06If you've landed after six or seven months of deep space cruise, you don't necessarily want to get out there
00:47:11and do an agility test or a maximum strength test right away.
00:47:14You may need a lander large enough to accommodate the entire crew in for a few days before you gain
00:47:19a little bit of strength and sea legs, if you will, land legs, so that you can walk to a
00:47:23habitat.
00:47:24Were there everyday things that you found really difficult to do when you came back to Earth?
00:47:29Yeah, I noticed a couple of weeks afterwards I was grocery shopping and I went to go reach for something
00:47:33on a high shelf and I kind of had a moment and had to stop and get myself together a
00:47:37little bit.
00:47:37And it's those really rapid head movements, anything where you're kind of changing the axis quickly will kick that issue
00:47:45off again, even if you're feeling fine just walking around.
00:47:47What was the strangest thing for you when you got back in terms of, wow, I didn't realize that I
00:47:52couldn't do that?
00:47:53I never really felt gravity before. I never understood it as an actual force.
00:47:57And you're incredibly aware the first few weeks after you land that gravity is very heavy.
00:48:02So something like picking up an iPhone, you know, it'll feel like it's five or ten pounds and you actually
00:48:07feel it falling towards the Earth when you try to put it down.
00:48:12You know, sitting there reading a book, trying to hold my hands up while I'm reading the book, I could
00:48:16feel gravity pulling my hands down and pulling the book down.
00:48:18And you adapt to that in everyday life. Your brain compensates for it. You never think about it.
00:48:22But you're definitely very, very aware of the very strong force that gravity affects upon us right after you land.
00:48:29So good job. Thanks. I want to high five enough. All right. Are you ready for another go? All right.
00:48:37All right.
00:48:39If colonists are going to arrive at Proxima B in a fit state, we need to stop these effects from
00:48:44happening.
00:48:45Get around the cone. Go.
00:48:59The problems with balance and muscle loss which Kate experienced are caused by the lack of gravity in space.
00:49:09And the longer you spend without gravity, the worse the effects.
00:49:21Exercise alone will not guarantee they will arrive in good hell.
00:49:26Maybe the answer is to simulate our own gravity in space.
00:49:31Researchers in Germany are trying to protect astronauts from muscle wastage by generating artificial gravity.
00:49:38So should I just lie down? Yes. Just lay down.
00:49:44All right. Perfect. Okay.
00:49:47This is a human centrifuge. When it spins, it exerts a force on my body, making me feel like I'm
00:49:54standing up and experiencing gravity.
00:49:57Do it right. I don't want to fly away.
00:50:01Okay.
00:50:01So first you do a comp check. Experiment operator.
00:50:05Yes. I can hear you.
00:50:06Can you hear me back?
00:50:08Wonderful.
00:50:12This is tight now.
00:50:14Okay. So just relax. Enjoy the ride.
00:50:16Okay. See you later.
00:50:21Locking door.
00:50:22To the stars.
00:50:24Starting five, four, three, two, one.
00:50:30Starting centrifuge.
00:50:31Centrifuge started.
00:50:33So the spinning has started.
00:50:37Now the effect of the centrifuge is that things are pulled from the center outward.
00:50:45I can feel my muscles and my bones and my legs being pushed against the footrest.
00:50:53So it kind of feels a bit like gravity.
00:51:00And I can feel my heart beating faster, trying to pump my blood back up.
00:51:09And it's quite a weird feeling.
00:51:14This is exercising not only my heart, but also the bones and muscles in my lower body.
00:51:20The same areas that weigh so dramatically during space flight.
00:51:24Wow.
00:51:26Now I really feel lightheaded.
00:51:30It truly does feel as if I'm standing almost upright.
00:51:36And the walls are spinning around me, but I'm not moving.
00:51:42I don't feel myself moving. I feel heavy.
00:51:46So your actual heart rate is 110.
00:51:54Stopping centrifuge.
00:52:00Oh, now my body is re-adapting to normal gravity.
00:52:05And that's not a nice feeling at all.
00:52:08It's like I'm falling backwards.
00:52:12It's a bit like when you're drunk.
00:52:15Et voilà.
00:52:16The centrifuge is safe.
00:52:18These guys think that if astronauts performed exercises while spinning in a centrifuge for just 20 minutes every day,
00:52:26their bodies wouldn't waste away in space at all.
00:52:29I really feel like you're standing.
00:52:31It's crazy.
00:52:32Yeah.
00:52:35However, this machine is currently only designed for use on the ground,
00:52:40to research the effects of artificial gravity on the human body.
00:52:45Installing enough of these centrifuges on a spacecraft to keep an entire crew healthy
00:52:49would mean an enormous amount of extra weight.
00:52:53But Professor Hawking thinks there might be a better way to use the same principle.
00:52:59There is a simple solution.
00:53:02Make the entire spaceship a centrifuge.
00:53:06A spaceship with the diameter of the London Eye
00:53:10would only need to rotate about four times faster than currently to counter the physical effects of space.
00:53:20Building rotating spacecraft is an easy way to overcome the human body's struggles with zero gravity.
00:53:29While there is impressive work being done to overcome the challenges posed by the lack of gravity in space,
00:53:36that isn't the only problem with sending humans to Proxima B.
00:53:43Deep space is full of radiation.
00:53:53And radiation is deadly to humans.
00:53:57It can infiltrate cells and damage DNA.
00:54:02Here on Earth, humans are protected because our planet generates a defensive shield.
00:54:08It can only be seen in the middle of the planet.
00:54:09But head to the poles and you can catch glimpses of its otherwise invisible power.
00:54:29This is the first time I see the Northern Lights in my life.
00:54:34I've been wanting to see them for years, since I was a kid I think.
00:54:40And they're huge! They're everywhere! The whole sky is lit!
00:54:49They are created by our own star, the Sun, which fires a constant stream of particles towards the Earth.
00:54:59Sometimes, bursts of these particles are so powerful that they reach our planet's atmosphere, producing these waves of color.
00:55:08This light show only happens in the skies above our polar regions because of the shape of our planet's magnetic
00:55:15shield.
00:55:16Far away under our feet, around the Earth's solid core, there is liquid iron turning around, creating a magnetic shield
00:55:26that protects our whole planet.
00:55:28Except at the poles, north and south, where solar particles can sneak in.
00:55:36We believe most of the stars in the Universe emit such radiation. There is radiation everywhere.
00:55:44And if we weren't protected by our own planet's magnetic field, we wouldn't be able to survive here on Earth.
00:55:54This shield extends for tens of thousands of miles into space.
00:55:59But, a crew would be far beyond this protection on a trip to Proxima B.
00:56:06This is another challenge that researchers will have to overcome.
00:56:19Radiation is one of the biggest problems facing deep space exploration.
00:56:25So far, scientists are yet to find material which is light and strong enough to block these radiations,
00:56:32or a feasible way of generating a magnetic field that could protect an entire ship.
00:56:37But nature might offer a way around this problem.
00:56:43Amazingly, the key to surviving radiation exposure on a journey deep into space might lurk in this enclosure.
00:56:52Hello, Rob.
00:56:54Dr. Robert Henning is a pharmacologist who has worked closely with the European Space Agency.
00:57:00There's a bear in that den, but it's too dark here to see it.
00:57:04But with a thermal camera, you can actually pick up its body heat.
00:57:09You can see a tiny white piece of the bear. It's just...
00:57:16That's the heat coming out of the bear.
00:57:18That's the heat coming out of the bear.
00:57:20Rob is interested in a bit of bear behavior, which no other large mammal exhibits.
00:57:26Hibernation.
00:57:28Hibernation is not sleeping. Hibernation is slowing of metabolism.
00:57:34So it's a bit like being alive, but in extreme slow motion, right?
00:57:39Yeah, yeah, absolutely.
00:57:41During hibernation, animals need virtually no food.
00:57:47If we could find a way of putting our crew into a similar state of hibernation on their journey to
00:57:52Proxima B,
00:57:53it would greatly reduce the amount of supplies they'd need to take.
00:57:58I can see why hibernation can be a very good thing for space traveling.
00:58:03But we do have a big problem in space, that there is a lot of radiation.
00:58:09And that could harm our DNA, so we need to find an answer to that.
00:58:12Well, the interesting thing is that hibernators are also protected from radiation.
00:58:18So you're telling me that bears hibernating in space would not be harmed by radiation?
00:58:24Yes.
00:58:26That's crazy, you know that.
00:58:27Yeah, yeah, yeah.
00:58:31Even more incredibly, Rob thinks he's found the key chemical that controls this process.
00:58:36And it could be used to put humans into hibernation and protect their DNA from radiation damage.
00:58:44He discovered this chemical in hibernating hamsters.
00:58:51This is a hamster cell which has been in the fridge for three days.
00:58:56Okay.
00:58:56And we left it accidentally there.
00:58:58It was not on purpose.
00:59:00We just forgot about it.
00:59:02And after three days, we came back.
00:59:04They looked pretty okay.
00:59:07And then we unscrewed the top.
00:59:10And then there came the big surprise.
00:59:17Oh, that's the rotten egg.
00:59:20That's hydrogen sulfide, right?
00:59:23Yeah.
00:59:24It smells bad.
00:59:25It smells bad.
00:59:26Yeah, yeah, yeah.
00:59:26So that means that the cells themselves produce...
00:59:29They produce the hydrogen sulfide.
00:59:32Now, we know that hydrogen sulfide can sort of replace oxygen.
00:59:36It's not as efficient as oxygen, but it's probably efficient enough to keep you alive.
00:59:43And so we think this is an important part of hibernation.
00:59:49Using a chemical very similar to hydrogen sulfide, Rob can put human cells into a state of hibernation.
00:59:58Astonishingly, when he exposes these cells to lethal levels of radiation, their DNA remains undamaged.
01:00:07So this compound protects against radiation damage.
01:00:12The long jump would be, maybe we should feed the astronauts this compound.
01:00:17But if we put a human into a hibernation, I don't have any idea right now how to wake them
01:00:25up and when to wake them up.
01:00:27So, knowing this, would you try to hibernate, to be put in hibernation?
01:00:36I think so, yeah, yeah.
01:00:38I mean, I've thought about it a long, long time and I just think that if I were the first,
01:00:45I would do it.
01:00:46I mean, to me, yeah, it sounds like a dream come true then.
01:00:55If Rob can use this chemical to create a serum for humans, then our astronauts could hibernate throughout the long
01:01:03journey to Proxima B.
01:01:04That would protect them from radiation and would mean they'd need far fewer supplies.
01:01:10Using new propulsion technologies and simulating gravity, they could be arriving at our new planet in a healthy state after
01:01:1820 years.
01:01:20But to fulfill Professor Hawking's vision, they must then face the epic task of building a new civilization when they
01:01:27get there.
01:01:32Colonizing the planet Proxima B will challenge our species like nothing before.
01:01:39Although we think it has similarities to Earth, it is very unlikely to be exactly the same as our current
01:01:46home.
01:01:47The crew may have to adapt to life in a very alien world.
01:01:58From what we can determine about Proxima B, our pioneers may need to brace themselves for a very strange climate.
01:02:07Although it sits in the Goldilocks zone, unlike Earth, not all of Proxima B is fit for human habitation.
01:02:16In fact, the habitable zone on its surface may not extend very far.
01:02:23Water here on Earth is liquid because of our planet's relationship with its star.
01:02:28Our star is the Sun.
01:02:32As the Earth orbits the Sun, it rotates.
01:02:39Most parts of the planet are warmed by the Sun to just the right temperature for water to exist as
01:02:45a liquid.
01:02:47But we think Proxima B is different.
01:02:51Its own rotation is likely to be synchronized with its orbit.
01:02:56The same side of the planet always faces its star, making it so hot, any water here would turn to
01:03:03gas.
01:03:04The opposite side never receives heat from the star.
01:03:09Any water here would solidify into a thick ice cap.
01:03:14Liquid water could only exist in a narrow strip between these two extremes.
01:03:21This is the only place that could support life and support us.
01:03:31Our colonists will need to use this precious area of land wisely.
01:03:36They must quickly master their surroundings and create a sustainable habitat.
01:03:42The limited supplies on their spacecraft will quickly run out.
01:03:46So their most pressing concern will be to start producing food in this alien environment.
01:03:53Luckily, there may already be a solution.
01:03:57On the Arctic island of Svalbard, people have been planning for the kind of event that might one day force
01:04:03us to leave this planet.
01:04:06Deep inside this mountain is one of the greatest treasures ever gathered by mankind.
01:04:12And one that may well prove crucial to colonizing other worlds, far away planets like Proxima B.
01:04:24We're going through a tunnel that will take us about 130 meters inside of a solid stone mountain.
01:04:31Of course, that does two things.
01:04:33One is it removes us from whatever accidents or bad things can happen on the outside.
01:04:37But it's also very cold here, so we have a natural freezer.
01:04:42A woman yesterday said to me, she said, you know, this is the most important room on Earth.
01:04:50And I hadn't really thought of it that way, but that's what it is.
01:04:56Here's the room with the most agricultural biodiversity on Earth.
01:05:01Think of it as a library of life.
01:05:04The Russian ones, Sweden, Mexico.
01:05:08For the last 30 years, Kerry Fowler has gathered together seeds of the most important food crops
01:05:14from virtually every country on our planet.
01:05:17He keeps them frozen here, in the global seed vault.
01:05:21The idea behind it is simple yet extraordinary.
01:05:26If crops fail because of climate change, war or disaster, these are the backups that will reseed the planet.
01:05:34This is a big corn maize collection here.
01:05:37We have probably more than 30,000 different varieties of that.
01:05:40And here's the Canadian collection.
01:05:42Here's a collection from Taiwan.
01:05:44And here, here's some boxes, very colorful, very strong from North Korea.
01:05:50Each one of these varieties has co-evolved with human beings.
01:05:54You can see our human culture embodied in these different varieties because people have selected for different characteristics the things
01:06:02that they wanted and needed.
01:06:04There is something kind of sad in what you're doing, but also quite, I don't know, reassuring.
01:06:13You know, think of this as just an insurance policy for agriculture and it's like any insurance policy.
01:06:19You never want to really use it.
01:06:22The sheer variety in this seed vault makes it the ideal place to find crops that may grow on Proxima
01:06:28B.
01:06:29Here's rice, not the Asian kind of rice, but African rice that grows in dry land conditions.
01:06:35So that might be something I would like to take on a journey in outer space.
01:06:40I wouldn't mind having some of it.
01:06:41Because rice, when you think of it, you need a lot of water to grow it.
01:06:46And that's not the case for this one.
01:06:47So you want something from this box.
01:06:51Here's a big bean collection that's come from Costa Rica.
01:06:54That's something your astronaut will want to take.
01:06:57You'd actually like to take a little bit of everything, frankly.
01:07:06This was built to protect the future of humanity on Earth.
01:07:11And the thing is, it may well protect the future of humanity in outer space as well.
01:07:18There are about one million different strains of crops inside these vaults.
01:07:23All of them having different properties, allowing them to grow in wildly different conditions here on Earth.
01:07:31Taking a broad range of seeds with us on a space journey may be our chance to finding the one
01:07:39crop that will thrive on another world.
01:07:42Allowing our species to colonize a new planet.
01:07:48On arrival on Proxima B, the colonists will be able to select the seeds best suited to the alien conditions,
01:07:56and create farms that will feed generations to come.
01:08:01But for our settlers, and their crops, to survive on another planet, there's something else they'll need.
01:08:09An atmosphere.
01:08:11Here on Earth, our atmosphere acts as a protective blanket.
01:08:16It insulates the planet, keeping it at a constant habitable temperature.
01:08:22It shields us from harmful radiation and cosmic rays.
01:08:27It creates atmospheric pressure that stops our bodily fluids from simply evaporating away.
01:08:35And crucially, it provides the oxygen we breathe.
01:08:43Currently, we don't know the composition of Proxima B's atmosphere, or indeed whether it has one at all.
01:08:51So if it doesn't have the oxygen-rich atmosphere we need, could we create one ourselves?
01:08:59We might find a solution by looking back at the history of our own planet.
01:09:05Oxygen in Earth's atmosphere wasn't present when the planet formed.
01:09:09It was created later, by life itself.
01:09:16Microbiologist Dr. Maria Farias works in the salt flats and lagoons of the Atacama Desert,
01:09:21studying these tiny planet-transforming creatures.
01:09:25Ah, bubbles.
01:09:27Bubbles, full of bubbles.
01:09:29Pure oxygen, you can see.
01:09:34These microbes are known as extremophiles.
01:09:37They thrive here, in these hostile conditions.
01:09:40Well, if that doesn't look like an alien life form, I don't know what it is.
01:09:44Those are microbial mats.
01:09:46Wow.
01:09:47This is all bacteria.
01:09:49This is only bacteria?
01:09:50This is a bacterial community.
01:09:52Yes.
01:09:53You see all the layers, many layers, different colors.
01:09:56Ah, I see.
01:09:57On the top you have orange.
01:09:59They are very resistant to UV radiation.
01:10:03Then you see green, okay?
01:10:05These green are cyanobacterias.
01:10:08All right.
01:10:09They do photosynthesis and they produce oxygen.
01:10:12It sounds extremely precious when you say it like that.
01:10:18These bacteria are known to have appeared on Earth over three billion years ago.
01:10:25Back then, the Earth was very hostile, with high UV radiation, volcanic activity, and a toxic atmosphere with barely any
01:10:34oxygen.
01:10:36So these things basically have changed the shape of the Earth.
01:10:42Yes.
01:10:42In extreme conditions, these microorganisms started to produce oxygen and to liberate it, and they changed the planet.
01:10:49They produced the ozone layer, and they made this blue planet and prepared the planet for another kind of life
01:10:57that depends on oxygen.
01:11:01If Proxima B lacks life of its own, it could lack the oxygen in its atmosphere to make it breathable.
01:11:10So, should colonists take along some extremophile cyanobacteria?
01:11:17You think these things could change the atmosphere of another planet?
01:11:21Yes, they did it in this planet. They could do it again.
01:11:26Making a hostile planet habitable like this is a process scientists call terraforming.
01:11:32And their ability to survive in extreme conditions makes these bacteria the perfect tools.
01:11:39To grow, they will use the carbon dioxide in the atmosphere and produce oxygen.
01:11:45Once there is enough oxygen, we send in plants and trees, and these will raise the oxygen level even faster.
01:11:53And then we wait until eventually the atmosphere becomes suitable for us, human, to breathe and live in.
01:12:03But we could be waiting a long time.
01:12:06It's estimated that to generate the oxygen we'd need to survive on an inhospitable planet,
01:12:11we'll have to terraform for hundreds of thousands of years.
01:12:16If Professor Hawking is right, and we should be colonising another world within the next hundred years, this is far
01:12:23too slow.
01:12:25So in the meantime, our pioneers will need to find another way to live and farm on a planet without
01:12:32an atmosphere.
01:12:36Fortunately for our colonists, agricultural engineers are already working on a solution.
01:12:47The campus agricultural centre is still in here.
01:12:52It's very busy.
01:12:55There's a lot of sheep around.
01:13:00It's really not what I was expecting.
01:13:11Hello.
01:13:13Hi.
01:13:14Here at the University of Arizona in Tucson, I'm meeting Professor of Space Agriculture, Jean Giacomelli.
01:13:23Jean.
01:13:24Howdy.
01:13:25Hi.
01:13:26Tanya.
01:13:26Welcome to the Wild West.
01:13:28Isn't this great?
01:13:29It feels very wild.
01:13:30It's great.
01:13:33Jean's working on a man-made structure that we could carry with us to allow us to live on a
01:13:38planet with no atmosphere.
01:13:41OK, Jean, so we arrive on a planet with no atmosphere.
01:13:44How are you going to keep me alive?
01:13:46Well, first we begin with a structure that could put something in between us inside and that harsh environment outside.
01:13:54The structure has to be lightweight and it has to be collapsible.
01:13:58Much like this, it would be collapsed during transport and then expanded outward once it got to the planet.
01:14:06Ah, I see it now.
01:14:07So what you have in your laboratory here is really just a giant version of this.
01:14:11Exactly.
01:14:13Well, then you have to put life support inside.
01:14:16Right.
01:14:16Oxygen and fresh water has to be there to keep the people alive.
01:14:21But how do you provide life support inside a tube when you're on an alien planet?
01:14:28And the answer is plants.
01:14:31Wow.
01:14:34Genes created a space survival pod that's filled with plants.
01:14:41This would allow a single human to live and breathe on a planet that had no natural atmosphere.
01:14:49As the plants photosynthesize, they will remove the carbon dioxide and provide all of the oxygen, all of the fresh
01:14:56water and half of the daily calories needed to sustain one person.
01:15:01These lights are so bright.
01:15:03These are LED lights, red and blue, and it's what the plant dictates to us that they need to grow.
01:15:09Gene's leaving me in charge of looking after the plants to let me experience what living in one of these
01:15:15pods on an alien planet might be like.
01:15:24I have to say, so far, living in such a small space without the ability to roam and explore isn't
01:15:31much fun.
01:15:34I'm getting bored now.
01:15:37I know what I'll do.
01:15:39I'll try some new music.
01:15:42See if you like meatloaf.
01:15:48You can't not like this, sweet potatoes.
01:15:57Feel a little bit like that dude on The Martian.
01:16:01Like I am completely alone.
01:16:06With no one to talk to, apart from the plants.
01:16:10And they're not great at conversation.
01:16:15And no one to sing to.
01:16:18Dancing to the night, dancing to the night, dancing to the night.
01:16:26I'm really bored.
01:16:30I'm really bored.
01:16:30Really bored.
01:16:32Jean's pods are small and light enough to be set up quickly.
01:16:38But if my experience is anything to go by, claustrophobia would drive our colonists insane.
01:16:45In the long run, we need to think bigger.
01:16:58This is Biosphere 2.
01:17:03Earth's biosphere is the invisible bubble of atmosphere, water and life that blankets our planet.
01:17:11Here, they've replicated it on a smaller scale, using some incredible feats of engineering.
01:17:23I find it incredible that just there is the Arizona desert.
01:17:27Yet inside these glass domes, we can recreate almost any environment on Earth.
01:17:33There's a rain forest.
01:17:37An ocean.
01:17:41And a desert.
01:17:46All created and maintained using man-made structures.
01:17:54This was originally built as the ultimate experiment into whether humans could sustainably live in the hostile environment of space.
01:18:04In 1991, eight people lived inside this completely sealed dome for two years.
01:18:12It's true they did go a bit stir-crazy in the end, but it's a lot more habitable than those
01:18:18small survival pods.
01:18:23In the miles of tunnels that sit underground beneath the greenhouses,
01:18:28Biosphere's director, Dr Joaquin Ruiz, shows me some of the technology required to keep Biosphere 2 running.
01:18:35So the infrastructure we see here just to replicate an Earth-like system is amazing.
01:18:41I mean, the engineering that we can see just around us is huge, isn't it?
01:18:44It is indeed. And all these things that you see here to your right is all the air cooling and
01:18:50heating that's required to keep the place alive.
01:18:52And that's the stainless steel that is underneath the whole biosphere so that there's no interactions between the soil and
01:19:00the biosphere itself.
01:19:01So the thing was sealed from the top and it was sealed from the bottom, and this is what it
01:19:05takes to cool the whole thing.
01:19:07The original experiment had two reasons for it being.
01:19:12One of them was trying to understand in detail how various biomes of the Earth operate, so there's an ocean
01:19:17and a rainforest.
01:19:18And the other one was what would it take to create a structure that you would build in another planet
01:19:23and you could basically live in it in a sustainable way.
01:19:28But there's no way we could actually take all of this though, is there?
01:19:31If you're going to be in another planet, you're going to have to deal with its atmosphere, you're going to
01:19:35have to deal with your growing plants.
01:19:37So yeah, something like this, or at least the concepts that are in here with different materials that aren't as
01:19:43heavy and so on, you would have to take.
01:19:49I'd never thought about the Earth systems from an engineer's perspective before.
01:19:57It's just incredible the amount of infrastructure required to mimic, even on a small scale, what our planet does for
01:20:05us naturally.
01:20:11It really does just bring home the engineering challenge required to support even just a handful of humans living in
01:20:19an alien environment.
01:20:24It would take the settlers decades to build something on this scale, and we currently have no way of transporting
01:20:32the heavy construction materials on a spacecraft.
01:20:37But might there be a way to have everything ready and waiting for us when we arrive?
01:20:43Could it be done by robots we send in advance?
01:20:54Robotics is something close to my heart.
01:20:57I'm fascinated by the revolution in capabilities.
01:21:00But are we really ready to send them to a distant planet like Proxima B?
01:21:04To start building a new civilization?
01:21:07Well, I guess it's time to ask the experts.
01:21:14At NASA's Kennedy Space Center, engineer Rob Muller is developing an army of autonomous robots that could set up an
01:21:22entire colony on Proxima B before any humans arrive.
01:21:28Starting with machines that can locate the raw materials we'd need to build habitations and infrastructure without having to transport
01:21:37them from Earth.
01:21:38These are incredible little things, aren't they?
01:21:42These are what we call the swarmies, which is a small robot designed to mimic the behaviour of ants.
01:21:50And they're very small and will have hundreds of these on the surface looking for resources.
01:21:56Inspired by ants, these robots will have sensors that can scan the planet's surface for resources such as water, metals
01:22:04and fuel.
01:22:05When one swarmy detects something, it sends a signal to the others to direct them to the same spot.
01:22:14In nature, the ants go around and they look for resources in a kind of a random walk.
01:22:20And they leave a pheromone trail behind.
01:22:22What we will do is track the same kind of pheromone trail in software.
01:22:26And then once the swarmies, which are mimicking the ants, find the resources, one of the robots will raise its
01:22:33hand and say,
01:22:33I found a resource, and all the other robots will converge by following the digital trail, the breadcrumb trail that
01:22:40we left in the software.
01:22:41That's incredible. So we're using strategies that you would find in nature, like in ants, to actually create the new
01:22:49generation of robots.
01:22:50Absolutely. We're using just thousands of years of evolution to our advantage.
01:22:57The swarmies could find everything we need to build a new colony within the surface of the planet itself.
01:23:04The material that you find on a planetary surface is called regolith. And regolith is crushed rock.
01:23:10It's been crushed by billions of years of impacts on these planetary surfaces. And so as a result, the crushed
01:23:15rock is extremely fine and dusty.
01:23:18If you just drive one stick, it moves one side. The other stick moves the other side. So it's kind
01:23:23of like a tank steer.
01:23:24So to drive forward, both sticks at the same time.
01:23:27Once the swarmies have located useful resources in this regolith, Rob and his team have developed a mining robot to
01:23:34dig up the material.
01:23:36So why are you scooping the surface? What are you hoping to find with that surface regolith?
01:23:40On the moon, 42% of the regolith by mass is oxygen. So if you needed breathing air, you would
01:23:47simply scoop up the regolith, process it and you're good to go.
01:23:51Wow. Yes. On Mars, you have hydrated minerals and you can extract the water from the hydrated minerals.
01:23:57Then you would have water for drinking, growing plants. And you can also electrolyze the water, get hydrogen and oxygen,
01:24:05which is rocket propellant.
01:24:06And then the waste material, even that's useful. You use that for construction.
01:24:14Rob's fully automated production line transforms the planetary dust into a mind-blowing variety of building materials.
01:24:23We can make many things. For example, this is some rope, stronger than fiberglass.
01:24:29This material here is a mixture of a polymer and a regolith. So this is concrete for space.
01:24:37Wow.
01:24:38This is rebar used already today. Instead of steel rebar, it doesn't corrode, it's very strong and it's very cheap.
01:24:46This is a paver that's in the shape of a puzzle piece. And this was done simply by taking the
01:24:52regolith, putting it in a mold and then you bake it in an oven.
01:24:56And we assemble these with robots and then we have a landing pad in space for landers to land on.
01:25:02Now, can you imagine launching this into space? I can barely pick this up.
01:25:06It makes a lot more sense to use the local materials and make it there.
01:25:11So you literally could do, could do everything. I mean literally everything we need to build a new civilization on
01:25:18another planet.
01:25:18Everything is there. We just have to have imagination and ingenuity.
01:25:25We have to invent new technologies so that as a civilization we can move into outer space to have a
01:25:30healthy future with abundance.
01:25:34Rob's vision shows us that sending robots to build a colony on Proxima B is possible.
01:25:40And it's the final piece in our technological jigsaw.
01:25:45We set out on this journey to explore Stephen Hawking's challenge.
01:25:50Can we leave our planet and set up a new home for humanity within a hundred years?
01:25:57It sounded impossible, but the scientists we've met are bringing this goal closer to reality than we'd ever imagined.
01:26:07We are making massive leaps in rocket technology.
01:26:11We're understanding how to protect our bodies in space.
01:26:16And even how to build a new civilization millions of miles from Earth.
01:26:20But do we believe these scientists will succeed within our time frame?
01:26:26Well, many of these projects may be in their fledgling stages.
01:26:31But just think about the progress we've made in the last hundred years.
01:26:35Our modern world of smartphones, satellites, air travel and the internet would have sounded like science fiction a century ago.
01:26:46History tells us that technology advances exponentially and unpredictably if we have the drive to succeed.
01:26:54You have all of these people who are working together for this common goal of finding the next Earth.
01:27:01It's passion. All these people are driven by passion and I love that.
01:27:06So just maybe within the next century, humans could be making a new home on a distant planet.
01:27:15Our species' natural curiosity is what will drive us to distant planets.
01:27:22But advances also come with a responsibility.
01:27:26Many of the reasons I think humans need to leave the Earth are down to the way we have used
01:27:32technology.
01:27:34Pollution, climate change, and even overpopulation, spring to mind.
01:27:41We must learn from mistakes we have made here on Earth.
01:27:46In the next 100 years, we will embark on our greatest ever adventure.
01:27:52Our destiny is in the stars.
01:27:56Space, here we come.
01:28:03To find out more about new worlds and life beyond Earth, go to bbc.co.uk forward slash new earth
01:28:12and follow the links to the Open University.
01:28:26Life in the extreme in Frozen Planet 2, David Attenborough's landmark new series reveals our icy world as never seen
01:28:34before on BBC iPlayer.
01:28:36Thank you so much for watching.��bc
01:28:39.co.uk The theme is
01:28:39çok güzel. The theme is
01:28:45the theme of the Friday's event. The theme is
01:28:45the theme song and the theme is the theme in spin, as the theme is, it is a theme song.
01:28:45It's a
01:28:45theme song and the theme song. The theme theme
01:28:51is the theme song and the theme song is the theme song by the fact that we will.
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