Solar storm brings spectacular aurora to parts of United States

Residents in Colorado, Georgia, Virginia, and Arkansas were treated to an unusual celestial display Monday night.

A solar storm hit the earth Monday afternoon, pushing shimmering solar auroras to places where they might be visible to more people.

A blast of magnetic plasma shot out of the sun at a speed far faster than usual, The National Oceanic and Atmospheric Administration said, causing the biggest solar storm the earth has seen definitely since March, but potentially since September 2005.

Auroras, more commonly called Northern Lights, are usually only seen at very high latitudes, but since Monday have been observed in the United States as far south as states like Georgia, Colorado, Virginia, and Arkansas, according to spaceweather.com, a website written by Dr. Tony Phillips of Science@NASA.

The solar storm, NOAA space weather physicist Doug Biesecker said, had not done any reported damage as of Monday, but probably caused current fluctuations in GPS and the electrical grid. He said the storm could last for more than a day.

Joe Kunches, director of space weather services at Atmospheric and Space Technology Research Associates, wrote in the Washington Post that those hoping to spot the lights should track a metric called the K-Index.

“The larger the K-Index, the farther south the aurora is dipping,” Mr. Kunches said, adding that mid-Atlantic states should look for an index of at least 8 – a threshold that is higher for southern states, and lower for northern states.

This report includes material from the Associated Press.