Mysteries of the Sun

Ionosphere, Thermosphere, and Mesosphere (ITM)

The ionosphere is a layer of plasma formed by the ionization of atomic oxygen and nitrogen by highly energetic ultraviolet and x-ray solar ra diation. The Ionosphere extends from the middle of the mesosphere up to the magnetosphere. This layer cycles daily as the daytime ex posure to solar radiation causes the ionization of the atoms that can extend down as far as the mesosphere. However, these upper atmospheric layers are still mostly neutral, with only one in a million particles becoming charged daily. At night, the ionosphere mostly collapses as the Sun’s radiation ceases to interact with the atoms in the thermosphere. There are still small amounts of charged atoms caused by cosmic radiation.

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