I'm Glyn Collinson from NASA's Goddard Space Flight Center
and I'm here today to tell you about the electric wind of Venus. So
Venus is cool. Venus is awesome. Venus is in many ways
one of the most Earth-like planets that we know of. One of the
the key ways that it's different is that it's very very dry.
With temperatures on the surface of 460 degrees
Centigrade whatever that is in Fahrenheit. You would never expect there to be
liquid oceans on the surface. That kind of temperature would only boils off
that water into steam. But the atmosphere of Venus is incredibly dry
so where did the steam go? So t talk about
how we remove something from a planet, we're going to have to talk about two forces
of nature. Firstly force of gravity. Gravity is the thing which is
holding you down to the planet. But if you think about it, it is also what is
holding the atmosphere down onto the planet as well. If I want to remove
some of the oxygen from the planet, we have to overcome
overcome that gravity. So to do that, I want to talk about the electric force.
It's the thing which your device is using right now to pump electricity
around its wires. It's pushing the electrons around the circuits. And what we think
can happen is that the electric force can help push on the ions
in the upper parts of the atmosphere push them off and up into space.
So just as every planet has a gravity field, we think
that every planet has a weak electric field. We went looking for
Venus' electric field and boy-oh-boy did we find it. It turns
out that Venus' electric field is at least five to ten times stronger than at Earth.
It's a monster of a force. It can rip heavy things
like oxygen straight out of the upper atmosphere and send them kicking and
screaming off into space. This really changes the way we thing about
planets because it turns out planets can lose
heavy things like oxygen to space entirely
through electrical forces in their ionospheres. This is something that is really
important if we want to go looking for exoplanets or habitable planets around
other stars. It is no good having conditions perfect for an
ocean and an atmosphere where you might want to breath if some invisible force is going
to come along a rip it all off into space. Only understanding
how atmospheres evolve can we understand how we got here.