Northern Lights

[Anca]

An aurora is a natural light display in the sky (from the Latin word aurora, "sunrise" or the Roman goddess of dawn), predominantly seen in the high latitude (Arctic and Antarctic) regions. The name ‘auroras’ is now more commonly used for the linguistic plural ‘aurorae’of ‘aurora’, so is adopted throughout the main text of this article. Modern style guides recommend that the names of meteorological phenomena, such as aurora borealis, be uncapitalized. Auroras are caused by charged particles, mainly electrons and protons, entering the atmosphere from above causing ionisation and excitation of atmospheric constituents, and consequent optical emissions. Incident protons also produce emissions, and convert to hydrogen atoms by gaining an electron from the atmosphere.

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