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Amazing Natural Phenomena

7 of the planet's most incredible spectacles

Text by Melissa Pandika

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Photo by Gregory Constantakis/TandemStock
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Aurora borealis and aurora australis

Named after the Roman goddess of dawn, the auroras cast an alien glow over the low-latitude Arctic and Antarctic regions. In the Arctic, they're known as the aurora borealis, or the northern lights, while the Antarctic equivalent is called aurora australis, or the southern lights. The haunting display occurs when highly charged electrons from solar winds collide with Earth's atmosphere. Solar winds flow from the sun along lines of magnetic force produced by Earth's core and bounce off oxygen and nitrogen atoms when they reach its upper atmosphere. The colors produced—green, red, blue, or violet—depend on which atoms the winds strike and the altitude where they meet. The magnetic and electrical forces react with each other in shifting combinations, seen as long curtains of color dancing across the sky.


 


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