WEBVTT FILE 1 00:00:00.020 --> 00:00:04.070 I'm Glyn Collinson from NASA's Goddard Space Flight Center 2 00:00:04.090 --> 00:00:08.270 and I'm here today to tell you about the electric wind of Venus. So 3 00:00:08.290 --> 00:00:12.590 Venus is cool. Venus is awesome. Venus is in many ways 4 00:00:12.610 --> 00:00:16.790 one of the most Earth-like planets that we know of. One of the 5 00:00:16.810 --> 00:00:20.830 the key ways that it's different is that it's very very dry. 6 00:00:20.850 --> 00:00:24.900 With temperatures on the surface of 460 degrees 7 00:00:24.920 --> 00:00:29.090 Centigrade whatever that is in Fahrenheit. You would never expect there to be 8 00:00:29.110 --> 00:00:33.370 liquid oceans on the surface. That kind of temperature would only boils off 9 00:00:33.390 --> 00:00:37.450 that water into steam. But the atmosphere of Venus is incredibly dry 10 00:00:37.470 --> 00:00:41.540 so where did the steam go? So t talk about 11 00:00:41.560 --> 00:00:45.680 how we remove something from a planet, we're going to have to talk about two forces 12 00:00:45.700 --> 00:00:49.890 of nature. Firstly force of gravity. Gravity is the thing which is 13 00:00:49.910 --> 00:00:53.950 holding you down to the planet. But if you think about it, it is also what is 14 00:00:53.970 --> 00:00:58.120 holding the atmosphere down onto the planet as well. If I want to remove 15 00:00:58.140 --> 00:01:02.310 some of the oxygen from the planet, we have to overcome 16 00:01:02.330 --> 00:01:06.450 overcome that gravity. So to do that, I want to talk about the electric force. 17 00:01:06.470 --> 00:01:10.630 It's the thing which your device is using right now to pump electricity 18 00:01:10.650 --> 00:01:14.850 around its wires. It's pushing the electrons around the circuits. And what we think 19 00:01:14.870 --> 00:01:18.890 can happen is that the electric force can help push on the ions 20 00:01:18.910 --> 00:01:22.930 in the upper parts of the atmosphere push them off and up into space. 21 00:01:22.950 --> 00:01:26.980 So just as every planet has a gravity field, we think 22 00:01:27.000 --> 00:01:31.110 that every planet has a weak electric field. We went looking for 23 00:01:31.130 --> 00:01:35.240 Venus' electric field and boy-oh-boy did we find it. It turns 24 00:01:35.260 --> 00:01:39.420 out that Venus' electric field is at least five to ten times stronger than at Earth. 25 00:01:39.440 --> 00:01:43.470 It's a monster of a force. It can rip heavy things 26 00:01:43.490 --> 00:01:47.500 like oxygen straight out of the upper atmosphere and send them kicking and 27 00:01:47.520 --> 00:01:51.760 screaming off into space. This really changes the way we thing about 28 00:01:51.780 --> 00:01:55.950 planets because it turns out planets can lose 29 00:01:55.970 --> 00:02:00.000 heavy things like oxygen to space entirely 30 00:02:00.020 --> 00:02:04.100 through electrical forces in their ionospheres. This is something that is really 31 00:02:04.120 --> 00:02:08.290 important if we want to go looking for exoplanets or habitable planets around 32 00:02:08.310 --> 00:02:12.350 other stars. It is no good having conditions perfect for an 33 00:02:12.370 --> 00:02:16.510 ocean and an atmosphere where you might want to breath if some invisible force is going 34 00:02:16.530 --> 00:02:20.580 to come along a rip it all off into space. Only understanding 35 00:02:20.600 --> 00:02:39.339 how atmospheres evolve can we understand how we got here.