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0:02
If humanity was forced to leave Earth and settle on another planet, where would we go? Well, Mars seems promising and it's close to Earth. But if you actually needed to survive there, well, good luck. Mars will freeze you, suffocate you, nuke your DNA with cosmic radiation, and crush your settler dreams under a dusty red sky. It's not a second Earth. It's a slow motion death trap. Surely, there's got to be another place out there for us to survive. Well, today we'll look at six
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of the most promising exoplanets to see which one could become Earth 2.0. We'll start with the closest planet to Earth, Proxima Centuri B. This exoplanet is only 4.24 light years away and its orbit is in its stars habitable zone. In the case of a huge disaster event like our sun exploding and wiping out the entire solar system, this planet would make for a great quick getaway, right? Well, not so fast. Four light years is still an incredible distance. If you owned a spaceship that
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could travel at the speed of light, it' still take you over four years to get to Proxima B. And face it, you don't have that kind of technology, do you? The fastest object humanity has ever built is NASA's Parker Solar Probe. And it travels at about 700,000 kmh. That's 430,000 mph. You can't travel in this probe because it's not meant for transporting humans. But if you could, it would take you 6,500 years to reach your destination. Yeah, not ideal. Space is really, really
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vast. and hopping from one planet to another takes a long time. So, let's just say that huge advancements in the fields of cryogenics and engineering were finally able to deliver you and your crew to Proximus Century B. Okay, now you're about to start a whole new civilization.
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The first thing you'd notice after you've touched down is how dim and red your new sun is. star you're looking at? Well, it's called Proxima Centuri. It's a red dwarf star that's seven times smaller and hundreds of times dimmer than the sun. Proxima Centtory B is tightly locked to its star Proxima Centuri, which means that one side is always facing Proximus Centuri and the other side is in constant darkness. Dayside temperatures here are hot, anywhere from 40° C to 100°. That's up
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to 212 F. And the night side, well, this side is too cold with lows close to -50° C. But smart you, you did your research and you landed in the planet's terminator zone. That's the area between constant day and never ending night. And it's balmy. Your thermometer reads at 15° C. That's 60 Fahrenheit. Great start. Now, as you begin to explore the planet, the ground is crunching beneath your feet. The wind is blowing dust in the air, but you're not worried. You've
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got a pressurized suit to keep you alive. Unfortunately, the atmosphere here is unbreathable. There's way too much carbon dioxide and almost no oxygen. Take your helmet off and it's game over. Now, you have to plan for a shelter. You see, the thing about red dwarf stars like the one you're facing, Proxima Centuri, is that they're violent and can send massive bursts of X-rays and ultraviolet radiation your way at any time. Setting up a solar storm shelter will be your first order of business.
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After one week, your crew has set up a basic habitat and shoveled a ton of soil. You've covered up the habitat with some of this soil to provide extra insulation. This is where you'll sleep, eat, and survive for the next few weeks. For power, you've set up wind turbines, making good use of Proxima Bee's breeze. If you hear a flare alarm, run to the radiation bunker you dug out in the ground. Here, you'll be safe until the star calms down.
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All right. By the end of the first month, you'll have built a second hub and you'll have a little greenhouse going. You'll be able to grow potatoes, algae, maybe even kale. It's not exactly gourmet, but it's enough to sustain you at first. Now, the first couple of months here would be a lot of engineering and strict rationing, but soon you'd be able to venture a little further and really start exploring the planet. And you'd get to be the one to name the first features.
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Twilight Spires, Echo Crater, Flatline Ridge. That last one is for Chase, He Who Dies in Space.
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And by the end of year 1, you'd finally be settled on this planet. You'd have everything you need to live here comfortably, more or less. You'd have a living quarters, a lab, a power grid, a radiation shelter, and the greenhouse. Your menu would expand beyond kale and potatoes to maybe something a little more tasty. Your outpost may be ugly, dusty, and constantly threatened by intense solar flares, but it works. You've made it. You live in a ribbon of twilight between
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fire and ice. One step too far in either direction, and you die. But you stay. You still couldn't take your helmet off or your space suit. The air here is still, as I said, unbreathable, but you're here for the long term. #planet goals. [Music] Okay, now after 10,000 years, your settlement has really made it. It's grown and evolved, and there are people everywhere. The people living here have spent centuries making use of oxygen generators that converted carbon dioxide
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into oxygen and have made the atmosphere breathable, at least for short periods of time. They still have to worry about humongous solar flares, but with bunkers all around the habitat, they've got it under control. Unfortunately, your generation of settlers has also been severely irdiated by the star. As much as you tried to avoid it, the radiation still affects the population. That's why you mostly stay in the habitat rather than go out and explore the planet further.
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Eventually, humans would outgrow the habitat and outgrow the terminator zone. They'd have to adjust to living in extreme cold or unbearable heat. And it's not the kind of life they pictured when they signed up to come here. Now, while Proxima B is largely a success, let's explore other worlds, too, like Trappist 1E.
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This exoplanet is 40 light years away from our galactic residence, and it's only slightly smaller than Earth. Trappist 1E orbits an ultra cool red dwarf star called Trappist 1 and it has six other Earth-sized neighbors, though only three are in the stars habitable zone. Luckily, Trappist 1E is in the Goldilock zone. That means it could have liquid water on its surface. And now you're about to step onto this alien surface and make it your new home. [Music] Okay, you've finally touched down on
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Trappist 1E, the most Earthlike of all the planets in the neighborhood. This alien rock will give you hope. As you step onto its soil, you'll see all six other Trappist planets the way you see the moon from Earth. You'll also notice the dim sun hanging low in the sky. Not the dim sum, the dim sun. That's Trappist one. This star is barely 9% the mass of our sun and it glows hundreds of times fainter. On Trappist 1E, you'll live in an eternal sunset. As you walk,
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the slightly weaker gravity would make your movements feel oddly graceful. Gravity here is about 90% of Earth's gravity. Now, just like on Proxima Centuri B, the best place to land here is the Terminator zone. That's right. Trappist 1E is also tidily locked to its star and you don't want to boil on its hot day side or freeze on its frigid night side. The temperature in the Terminator zone might be brisk but not unbearable. Just a few degrees above 0° C, 32 F. You take
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a deep breath inside your pressurized suit and you get ready to do some work. Your first priority is to establish life support and safety. The atmosphere on Trappist 1E could be breathable, but you still keep your helmet on. You'd need to test the air for toxins and harmful microbes first. [Music] Now, Trappist 1E has one thing Proxima Centtory B does not. Water. With an oxygen-rich atmosphere, water, gorgeous views, and a never-ending sunset, this planet is a pretty good contender for
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Earth 2.0. Your team has now confirmed the air is breathable, but you don't want to risk it. Not yet. You didn't travel all this way from Earth just to die on this rock. You'll set up your main habitat near a water source. Your crew will deploy a water extraction system to filter the water. You'll also set up a greenhouse module and start growing plants for food. But the dim light from the star isn't enough to give your plants the energy they need. So, you'll rig up some
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LED lights above your greens. Kale is still on the menu. Just like on Proxima Centtory B, you're going to need a radiation shelter. Yeah, this star, it spews out violent bursts of radiation, and you never know when to expect them. After your first month on this planet, you'll be pretty confident that you could make it work here. I mean, what choice do you have? It's not like you could turn back and travel the 40 light years back to Earth. Your camp is growing. You now have a larger radiation
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shielded habitat and a nuclear power source. And here's a relief. The atmosphere is safe. So is the environment. If the air or soil had toxic chemistry, you would have seen the effects by now. Instead, you've discovered that Trappist 1E has near Earthlike conditions. I mean, apart from the unpredictable and violent solar flares. Luckily, most of those are happening on the day side. So, as long as you don't venture too far from the Terminator zone, you'll be fine. You'll
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be doing a lot of science, further testing the air, soil, and water for chemical composition, and potentially even some microbial alien life. Yeah, you might not be the first settler on this world. You'd even start taking off your helmet. It's still risky, but Trappist onee seems safe for now.
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A century has gone by and now the human population has grown to several hundred people. Your settlement is now self-sufficient. Over the decades, more ships arrived from Earth. The new arrivals brought fresh supplies, more settlers, and updated equipment. With these advancements, Trappist 1e now has multiple settlements spread across the planet. Once again, you succeeded on an alien world, but there's still that issue of solar flares and radiation. While Trappist one might not be so bad
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for life, it's still not perfect. And there are so many other alien worlds out there. Don't settle on this one just yet. While we're imagining ways to make distant exoplanets habitable, we need to remember that millions of people still don't have clean water down here on Earth. not for drinking, cooking, or even in hospitals. And that's not a what if hypothetical. That's real life for one in 10 people on this planet. The good news, well, we can work together to
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change that. We at What If are proud to join Team Water, a global creator-led campaign started by Mr. Beast and Mark Robber to bring clean water to 2 million people for decades to come. This is happening right now and we have to move fast. Our goal is to raise $40 million by August 31st. Creators worldwide are teaming up to bring their communities together and make it happen. And you can help, too. Just $1 can provide someone with the clean water they need for an
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entire year. And I'm not just talking about handing out water bottles. We're talking about building real lasting systems like solar powered pumps, water piped into schools and homes, and rainwater harvesting solutions that communities can run themselves. If you're inspired to make a difference right here on Earth, well, head to teamwater.org and donate. Use #team water and let's make history together. Okay, now that we're helping out our own planet, let's see what else we can do
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with the exoplanets we find out there. This world ahead, that's K218b. [Music]
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K218b is one of the most exciting exoplanets ever discovered. It lies just 120 lighty years away and orbits within the habitable zone of a red dwarf star. This world is about 2 and 1/2 times the size of Earth and has about 8 and 1/2 times as much mass. The hope is it's a super Earth covered in oceans. The worst case scenario, it's a mini Neptune. It likely has a thick hydrogen-rich atmosphere. Good for trapping heat. Terrible for breathing. But here's the exciting part. Scientists have detected
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methane, carbon dioxide, and even dimethyl sulfide, a chemical that's produced by marine life here on Earth. That could be a major clue that we're not alone. If you were to settle on K218b, you wouldn't land on solid ground because, well, there might not be any. And if there is, the volcanoes and quakes might make it too unstable. Anyway, so what do you do? Well, you build a floating habitat. And no, I'm not talking about a habitat on the water. I'm talking about one hovering just
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above the cloud tops. An alien cloud city. You'd need shielding from intense radiation, sturdy structures to resist weather, and a way to extract water and nutrients from the atmosphere or the ocean. It'll be dangerous and you might fail, but at least you'd try something new and exciting. All right, let's look at another potentially habitable world. Kepler 186F.
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This rock made history. Kepler 186f was the first Earth-sized exoplanet ever discovered orbiting in the habitable zone of its star. When astronomers announced it in 2014, it became a possible Earth 2.0. That's where the good news starts. That also where it kind of ends. Kepler 186F orbits a small, cool red dwarf star called Kepler 186. The planet sits right at the outer edge of the habitable zone, which means it's not getting a lot of sunlight. To be exact,
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it receives only about 32% of the solar energy that Earth gets from the sun. Without a thick heat trapping atmosphere, it's likely a frozen world. Now, if there is water ice here, you'd need a serious thermal energy system to thaw it. And forget about using solar panels, at least not as your main power source. That red dwarf sun, it's just too faint. You'd have to rely on nuclear generators like NASA's Kilopower fishing reactors to power your base and keep it warm.
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There's also a logistics problem. Kepler 186F is the only planet in its systems habitable zone. The other known planets orbit much closer to the star and are scorched. So, if this place doesn't work out, there's no plan B nearby. And you're 500 light years from Earth. No resupply missions, no rescue ship, no turning back. And if you think 500 light years is already pushing it, well, you might not like where we're going to take you next because this next planet is 1,200 light years away.
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[Music] Kepler 62F is a super Earth exoplanet in the habitable zone of its star. The star is called Kepler 62, a K-type orange dwarf that's cooler and dimmer than our sun. The planet itself is about 1.4 times the size of Earth and it orbits much further out than Earth does. That means it receives significantly less warmth and light from Kepler 62. This would make most of Kepler 62F very, very cold, especially if it lacks a thick atmosphere. Large portions of the planet
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could be permanently frozen. But if you give this world the right atmosphere, everything changes. If Kepler 62F had an atmosphere at least three to five times thicker than Earth's that was mostly made out of carbon dioxide, well then it could trap enough heat to make parts of the planet temperate and stable. If you were setting up a settlement here, your best bet would be to pick the warmest spot on the dayside, ideally near the equator. You'd still need radiation shielding, atmospheric
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processors, and heated shelters, but you could make it work. Kepler 62F is 1,200 light years from Earth, so you're definitely not commuting back and forth. But if you're willing to terraform a little or a lot, this frozen super Earth might just have what it takes to be your future home. Okay, let's take a little break from the Kepler family and swing by a different neighborhood.
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TOI700 is a cool, quiet red dwarf star just 100 lighty years away. And guess what? It's not constantly erupting with flares trying to cook you alive. This is progress. This star hosts four planets. And the real standout is TOI700D cuz it's the only one in the habitable zone. TOI700D is about 20% larger than Earth with gravity just a tad stronger than what you're used to. And it gets about 86% of the sunlight we get back at home, which sounds pretty perfect. Where I live, I
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feel like I only get about 50% of Earth's sunlight. The only hiccup with TOI700D is that this planet is, say it with me, tidily locked to its star, which means one side is always day and the other side is always night. But you already know what to do. Yes, that's right. Head for the Terminator zone. Of course, you'll still need pressurized shelters, radiation shielding, and life support systems while you find out if the atmosphere is breathable. And while TOI700D
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seems calm on the surface, this planet comes with a few surprises. For one, we don't know what the air is made of. Could be oxygen rich and friendly, or it could be a carbon dioxide soup that melts your lungs. So, don't ditch the helmet just yet. And what if there is an atmosphere? Well, buckle up. That much heat on one side and cold on the other can create wild weather systems. Think supersonic winds howling through your camp at all hours. And then there's the water or the
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lack of it. We haven't confirmed any surface water yet. So, you'll either have to bring your own or extract trace amounts from the air if the air exists. Not sure I like TOI 700D so much. So, all these alien worlds have potential, and there are plenty more out there for you to explore and possibly settle on. As long as you know that you'll be building an entire civilization in a place where everything wants you dead. Yeah, it would be a lot of effort not to die on these worlds,
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but persevere because perishing on them wouldn't be pretty. But that's a story for another. What if?
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[Music]
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