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The atmosphere of the Sun (corona) is the place of the departure of a plasma flow (electrically neutral mixture of ions and free electrons) linked to magnetic fields, which is known as the solar wind. Due to the Sunís rotation, this jet ends up assuming a spiral archimedean shape, which extends until a distance of 7000 million km (beyond the orbit of Pluto).


The solar magnetic field, under the shape of an archimedean spiral (The New Solar System - 3rd edition)



The solar wind ends up merging with the interstellar environment and losing its identity at a distance of 15 000 million km from the Sun, 100 times higher than the one that separates the latter from the Earth (the heliopause). Beyond the heliopause it may eventually be possible to detect interstellar winds, proceeding from far more distant sources, holding different velocities, compositions and directions.


Planetary Magnetic Fields

The magnetic fields of the planets are stretched by the solar wind, producing magnetic tails that extend through millions of kilometres. Some particles of the solar wind, captured by the planetary magnetic fields (of the inner and the outer region), rain over the planetary atmospheres producing what we know as "polar aurorae", resulting from the reactions with the gases that are present at the upper atmospheres.


Polar aurora, in Australia (Craig Richardson)



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