EXTREME SPACE WEATHER: 20 years ago today, a powerful CME slammed into Earth's magnetosphere, sparking an extreme geomagnetic storm. Bright auroras were seen as far south as Houston, Texas, and San Diego, California. Technological systems avoided damage mainly because a second CME arrived later in the day and, ironically, turned the storm off before it could grow any stronger. Learn more about this fascinating event on Spaceweather.com.
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Above: Auroras near San Diego, California, on March 31, 2001. Photo credit: Dennis Mammana.
