Aurora Borealis is another name for the Northern Lights (Aurora Australis for the Southern Lights). It is caused by energetic charged particles which originate from the sun. In the upper atmosphere, the particles interact with the atoms and molecules in the atmosphere, creating ionization and the emission of light, with a wavelength (color) depending on the ionization energy. Different atoms cause different colors of aurora, red and green (from Oxygen and Nitrogen) being the most prevalent. Aurora usually looks like curtains of red, green, blue or purple light, and can be an awe-inspiring view.
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