Page 20 - Curriculum Visions Dynamic Book

Solar wind
The magnetosphere and the auroras
The magnetosphere is a giant invisible shell beyond the Earth’s atmosphere. It reaches about ten Earth diametres in front of the Earth and several thousand Earth diametres back into space, forming a tail.
The magnetosphere does not contain
any air from the Earth, but it is where the magnetism from the Earth reaches out
into the solar wind (the flow of charged particles from the Sun). The power produced in this region is about 100 billion watts, and part of that power produces the nighttime displays called aUroras.
 Two forms of aurora seen from space.
 This cross section shows the way the magnetosphere is buffeted by the solar wind. The result is to squash the magnetosphere in the direction of the solar wind and to produce a long tail in the “lee” of the Earth.
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