©Planeterrella
The polar light simulator

Demonstration

Other configurations

There are a large number of possible configurations with the Planeterrella.
Everything is mobile : the electric duct can move on its axis and on its stem, the poles of the spheres can move up and down like the foot of an umbrella, we can naturally change the locations of the sphères, the gas pressure and the intensity of the electric current can change. Soon, the spheres will also rotate around their geographical axis and electromagnet will allow to change the magnetic field intensities. (...)

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Uranus

Can we use the Planeterrella to make predictions ? Perhaps ...
The plane in which the planets revolve around the Sun is called the ecliptic plane. The planets have also their own rotation around a geographical axis. The Earth rotates in about 24 hours on itself. Often, the rotation axis is tilted from the vertical perpendicular to the ecliptic, creating a seasonal phenomenon. This angle is called the inclination. Its value is about 23.3 degrees in the case of the Earth. Mercury is not (...)

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Magnetopause

This observation is difficult to perform with Planeterrella I, easier with Planeterrella II and since November 2012, very easy with Planeterrella III. In the first case, one must indeed use a strong power supply, tens of milli-amperes (warning ! One must be very careful with such intensities). In the second case, it suffices to approach the spheres as they are now mobile. We can even see – maybe for the first time in the world – the birth of a magnetosphere and a bow shock! To make this (...)

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Stellar jets like

This is a new configuration possible with the Planeterrella. Here, the large sphere is a star, and we are increasing the pressure in the gas chamber to more than 100 Pa. We are in the presence of a highly magnetized star with a dense atmosphere (for a stellar corona). Under this pressure, we had an expanding solar wind. But above this limit, this corona narrows to focus around magnetic poles in stellar jets. The Debye area is clearly visible close to the star, but more spectacular, a cone (...)

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Van Allen

What is observed here has been little or not at all observed by K. Birkeland. The ease of modern equipment to change configurations is one reason: it took at least three weeks to Birkeland to proceed to a change that takes less than half an hour today ! But the flexibility of the Planeterrella mounting is the major reason.
In this configuration, the large sphere is a planet, which receives its stellar wind either from the electric nozzle or from the smaller sphere (which in this case is (...)

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Stellar ring current

We are here in the world of Birkeland who also largely observed this configuration, and wrote several scientific papers. Unfortunately, Birkeland has not given the correct interpretation: he claimed to have demonstrated the origin of the rings of Saturn. The astronomers argued against this interpretation, arguing that Saturn does not produce electricity, and that the rings had been clearly identified as rocks and ice. But K. Birkeland refused this vision of things. He concluded that most of (...)

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Presentation

A star is a stellar object that emits energy in the form of radiation and electrical particles (electrons and ions). The wind of particles is called the « stellar wind » and, in the case of the Sun, the « solar wind ». In our experiment, we can connect either an electric duct (ie a simple metal tube), and / or one or two spheres to the négative pole of our generator (which is nothing more than a big electric battery, producing continuous current). In the description of the experiment, we call "a (...)

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Pictures

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Movies

Here are some movies with the Planeterrella. While following the links here after, you can view 4 very didactic videos presenting for the first the phenomenon of the polar lights, for the second the original experiment of Birkeland, the third is a discovery of the manipulation of Planeterrella of Jean Lilensten and finally, the last presents some simulations of dawns realized using Planeterrella.
Le phénomène des aurores polaires Le phénomène des aurores polaires (...)

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Coronal holes

We now leave the world of Birkeland. The large sphere is connected to the négative pole of the generator and emits electricity. It thus becomes a star. The small sphere, or eventually the nozzle is connected to the positive electric pole of the generator and represents is a planet.
If the small sphere is a planet, the auroral ovals are clearly visible.
We concentrate on our star. The electrons are emitted over the whole surface, but are repelled from the magnetic poles themselves. Away (...)

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Aurora ovals

We are in the world of Birkeland. He also widely observed this configuration, from which he published numerous scientific articles. This is with these observations that he demonstrated the mechanism of the polar lights. He came to William Thomson [1824-1907] (not to be confused with JJ Thomson [1856-1940], the physicist who had discovered the electron in 1897). But Thomson did not believe Birkeland’s theory: "where electrons exit, there must also be protons. Where are they? ". Soon, Thomson (...)

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Institut de Planétologie et d'Astrophysique de Grenoble (IPAG)