THE GREAT GEOMAGNETIC STORM OF MAY 1921: 100 years ago today, the biggest solar storm of the 20th century struck Earth. Buildings caught fire, telephone lines burned out, and auroras were sighted from ships at sea crossing the equator. What would happen if such a storm struck today? Get the answers @ Spaceweather.com.
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Above: Newspaper headlines from May 15, 1921 (New York Times, Brooklyn Daily Eagle, Buffalo Courier)
