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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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