WEBVTT FILE

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I'm Glyn Collinson from NASA's Goddard Space Flight Center

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and I'm here today to tell you about the electric wind of Venus. So

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Venus is cool. Venus is awesome. Venus is in many ways

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one of the most Earth-like planets that we know of. One of the

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the key ways that it's different is that it's very very dry.

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With temperatures on the surface of 460 degrees

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Centigrade  whatever that is in Fahrenheit. You would never expect there to be

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liquid oceans on the surface. That kind of temperature would only boils off

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that water into steam. But the atmosphere of Venus is incredibly dry

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so where did the steam go? So t talk about

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how we remove something from a planet, we're going to have to talk about two forces

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of nature. Firstly force of gravity. Gravity is the thing which is

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holding you down to the planet. But if you think about it, it is also what is

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holding the atmosphere down onto the planet as well. If I want to remove

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some of the oxygen from the planet, we have to overcome

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overcome that gravity. So to do that, I want to talk about the electric force.

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It's the thing which your device is using right now to pump electricity

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around its wires. It's pushing the electrons around the circuits. And what we think

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can happen is that the electric force can help push on the ions

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in the upper parts of the atmosphere push them off and up into space.

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So just as every planet has a gravity field, we think

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that every planet has a weak electric field. We went looking for

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Venus' electric field and boy-oh-boy did we find it. It turns

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out that Venus' electric field is at least five to ten times stronger than at Earth.

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It's a monster of a force. It can rip heavy things

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like oxygen straight out of the upper atmosphere and send them kicking and

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screaming off into space. This really changes the way we thing about

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planets because it turns out planets can lose

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heavy things like oxygen to space entirely

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through electrical forces in their ionospheres. This is something that is really

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important if we want to go looking for exoplanets or habitable planets around

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other stars. It is no good having conditions perfect for an

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ocean and an atmosphere where you might want to breath if some invisible force is going

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to come along a rip it all off into space. Only understanding

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how atmospheres evolve can we understand how we got here.