Astrophysics (index)about


(light produced by atmosphere and solar wind)

An aurora is electromagnetic radiation (notably visible light) produced by interactions between a planet's atmosphere and a stellar wind,

Earth's atmosphere is protected from the solar wind by the Van Allen belts, and auroras are normally confined to regions near the poles, but solar events increasing the wind can overcome blocking effect, resulting in auroras further from the poles.

When the solar wind (electrons, protons and heavier ions) strikes the upper atmosphere, collisions excite and ionize molecules in the atmosphere, and EMR is produced by this process and subsequent electron relaxation and recombination.

(EMR,Earth,solar wind)

Referenced by:
magnetic reconnection