Magnetosphere
A magnetosphere is formed when a stream of charged particles, such as the solar wind, interacts with and is deflected by the magnetic field of a planet or similar body. Earth is surrounded by a magnetosphere, as are the other planets with intrinsic magnetic fields: Mercury, Jupiter, Saturn, Uranus, and Neptune. Jupiter's moon Ganymede has a small magnetosphere, but it is situated entirely within the magnetosphere of Jupiter, leading to complex interactions. The ionospheres of weakly magnetized planets such as Venus and Mars set up currents that partially deflect the solar wind flow, but do not have magnetospheres, per se. The magnetosphere is caused by the movement of electrical currents in the outer core of the earth. The outer core is of a liquid state while the inner core is of a solid state due to the immense amount of pressure it experiences. The Magnetosphere is nothing but the magnetic field that prevents the solar winds, or highly energetic particles that come from the sun's corona from completely depriving the earth of its oxygen. If the magnetosphere did not exist, then Earth would not be able to sustain life.
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