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there's a planet in our galaxy that

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scientists are really excited about in

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fact it's the closest earth-sized planet

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outside our solar system it's probably

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rocky and could have liquid water

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flowing on its surface an essential

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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

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to get to proxima centauri b it would

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take a spacecraft over 75 000 years to

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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

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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

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can't see and you can't get to

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this supercomputer is tasked with

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running sophisticated climate models to

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predict earth's future climate it's loud

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you can feel air rushing by you can feel

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a hum in the room it feels powerful it's

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one of the most powerful supercomputers

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in the world

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and now it might be scientists only hope

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for discovering whether any of these

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newly discovered planets could possibly

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last year a team at nasa goddard

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institute for space studies in new york

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city decided to investigate further

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what happens when you take a possibly

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rocky planet situated in its solar

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system's habitable zone and simulate

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hypothetical climates based on the only

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planet we know of with life

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earth

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we only know basic details about proxima

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centauri b its size

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mass distance from its star and the type

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of star it orbits and that's it

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right out of the gate proxima b has some

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problems

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it's 20 times closer to its star proxima

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this means that it's likely

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gravitationally locked to it just like

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the moon is gravitationally locked to

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the earth

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as a result one side of proxima b always

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faces its sun's intense radiation while

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the other freezes in the darkness of

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space

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but slap on a hypothetical atmosphere on

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the planet and fill it with an ocean and

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[Music]

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here's where this gets interesting

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we're looking at the side of proxima

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centauri b that's facing its star so

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it's the warmer side

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in the simulation the modelers gave the

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planet a global ocean

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the ocean circulates heat around the

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planet through ocean currents that are

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produced by the planet's rotation just

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as we see on earth

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the ocean current actually carries warm

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water to the side of the planet without

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starlight and up towards the poles

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this creates a characteristic pattern of

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ice-covered ocean similar to our own

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north pole versus ice-free ocean

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a pattern we would see on any rotating

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ocean-covered planet

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in this simulation modelers use earth's

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continents as a stand-in to predict what

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would happen if most of the land was on

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the side of the planet facing away from

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its star

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how much land might be covered in ice

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and how might ocean currents interact

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with land masses when transferring heat

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[Music]

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conversely if most of the continents

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face the warmth of its star

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how much incoming radiation would

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actually be absorbed by the ocean and

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how could this affect the planet's

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so those are some of the tricks we play

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we give it different kinds of

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atmospheres and see how the planet

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responds the climate response to that

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because we really want the planet to be

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in in what we call the habitable zone

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where it would have liquid water on its

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scientists are finding these exoplanets

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could actually have ingredients to

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support life under a range of surprising

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conditions compared to earth

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is it possible that our notions of what

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make a planet suitable for life are too

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limiting

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had alien civilizations pointed their

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telescopes towards earth billions of

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years ago expecting to find a blue

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planet swimming in oxygen they would

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have found a much different world we

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definitely look at earth through time we

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might try different topographies

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different land sea masks for example

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you know the topography we have today on

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earth is not the topography earth had

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250 million years ago

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with money and time both limited

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resources scientists are looking for the

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most promising planets to point their

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observatories at

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proxima centauri b may offer a blueprint