Magnetosphere of Jupiter

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I would like to write about one of my most favourite topics: the Jupiter's magnetosphere. Jupiter is really significant planet in our solar system. It is the fifth planet from the Sun and the largest in the solar system. The magnetosphere is the cavity created in the solar wind by the magnetic field of the planet. Also the magnetosphere is the largest and most powerful from all planetary magnetospheres in our solar system.

To show different sizes and how huge is the Jupiter's magnetosphere I like to show the following sketch. Let's start from the planet Mercury on top left panel and going to the top right to the Earth's magnetosphere. Then let's continue down right to the planet Saturn and then let's finish on the bottom left panel of the planet Jupiter.


For the magnetized planets, those with intrinsic magnetic fields, the obstacle to the solar wind is the planetary magnetic field and the size of the magnetosphere is governed by the relative strengths of the magnetic field and the solar wind at the planet.

From Wiki: sketch

Lila line represents the border of the magnetosphere. The outer border called bow shock is the first structure where the solar wind interacts with the magnetosphere and the solar wind is decelerated and deflected from the original direction around the magnetosphere. Unlike the Earth's magnetosphere the solar wind plasma and Jupiter's magnetosphere plasma are fully separated, which shows that the dynamics within the magnetosphere is driven differently than in case of the Earth's magnetosphere.  

The volcanically active moon Io is a strong source of plasma loading Jupiter's magnetosphere with about 1000 kg of new material per second. Io emits sulfur dioxide. Major amount of it is dissociated into atoms and ionized by the solar UV radion, producing ions of sulfur and oxygen, which escape the atmosphere of Io and form thick and relatively cool ring of plasma, called the Io plasma torus. The temperature inside the torus is about 10 to 100 eV, compared to the temperature of the particles of Jupiter's radion belts about 10 keV. The plasma in the torus is co-rotating with Jupiter.  


Jupiter has bright and persistent auroras around both poles. Unlike the Earth's auroras, which depend on the solar activity, Jupiter's auroras are permanent, only their intensity is varying. Jupiter's auroras consist of three parts: the main ovals, the footprints of moons (where Io is the most dominant), and transient polar emissions within the main oval.




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