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There’s a planet in our galaxy that scientists are really excited about. 

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In fact, it’s the closest Earth-sized planet outside our solar system,

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it’s probably rocky, 

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and could have liquid water flowing on its surface 

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– an essential ingredient for life. 

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 There’s only one problem. 

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We can’t actually see it and it’s impossible to get to.

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To get to Proxima Centauri B, it would take a spacecraft over 75,000 years 

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to travel there with today’s technology. 

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Even powerful ground-based telescopes 

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can’t see the planet in any detail 

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mostly because it’s being drowned out by the light of its star. 

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This raises the question: 

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How do we investigate a planet that you can’t see and you can’t get too?

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This supercomputer is tasked with running sophisticated climate models 

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to predict Earth’s future climate. 

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It’s loud, you can feel air rushing by, you can feel a hum in the room

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It feels powerful. 

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It’s one of the most powerful supercomputers in the world. 

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And now, it might be scientists' only hope for

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discovering whether any of these newly discovered planets

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could possibly sustain life.

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Last year, a team at NASA Goddard Institute for Space Studies 

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in New York City decided to investigate further. 

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What happens when you take a possibly rocky planet 

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situated in its solar system’s habitable zone 

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and simulate hypothetical climates based on the

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only planet we know of with life – Earth. 

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We only know basic details about Proxima Centauri B 

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Its size, mass, distance from its star, and type of star it orbits. And that’s it. 

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Right out of the gate, Proxima B has some problems. 

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It’s 20 times closer to its star, Proxima Centauri, than Earth is to its Sun

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This means it’s likely gravitationally locked to it, 

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just like the Moon is gravitationally locked to the Earth. 

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As a result, one side of Proxima b always faces its sun’s intense radiation, 

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while the other freezes in the darkness of space.

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But slap on a hypothetical atmosphere on the planet 

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and fill it with an ocean, and Proxima B virtually comes alive. 

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Here’s where this gets interesting.

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We’re looking at the side of Proxima Centauri B that’s facing its star,

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so it’s the warmer side. 

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In this simulation, the modelers gave the planet a global ocean.  

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The ocean circulates heat around the planet through ocean currents 

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that are produced by the planet’s rotation, just as we see on Earth.

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The ocean current actually carries warm water to the side of the planet without starlight,

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and up towards the poles.  

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This creates a characteristic pattern of ice covered ocean 

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similar to our own North Pole

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versus ice-free ocean – a pattern we would see on any rotating ocean-covered planet. 

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In this simulation, modelers use Earth’s continents as a stand-in to predict 

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what would happen if most of the land was on the side of the planet 

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facing away from its star.

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How much land might be covered in ice, and how might ocean currents 

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interact with land masses when transferring heat?

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Conversely, if most of the continents faced the warmth of its star

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how much incoming radiation would actually be absorbed by the ocean, 

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and how could this affect the planet’s dayside and nightside temperatures?

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So those are some of the tricks we play. 

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We give it different kinds of atmospheres, and see how the planet responds,

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the climate responds to that because we really want the planet to be 

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in what we call the habitable zone

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where it would have liquid water on its surface.

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And so that’s the game we play.

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Scientists are finding these exoplanets could actually have

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the ingredients to support life under a range of surprising conditions compared to Earth. 

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Is it possible that our notions of what make a

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planet suitable for life are too limiting?

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Had alien civilizations pointed their telescopes toward Earth billions of years ago 

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expecting to find a blue planet swimming in oxygen,

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they would have found a much different world. 

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We definitely look at Earth through time. 

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We might try different topographies, different land sea masks. 

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For example, you know, the topography we have on Earth

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is not the topography Earth had 250 million years ago.

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With money and time both limited resources, 

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scientists are looking for the most promising planets to point their observatories at.

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Proxima Centauri B may offer a blueprint 

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for what to look for in a planet in the near future. 

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