That means "a whole host of things" could follow, he said.
North American utilities are monitoring for abnormalities on their grids and have contingency plans, said Kimberly Mielcarek, spokeswoman for the North American Electric Reliability Corporation, a consortium of electricity grid operators.
In 1989, a strong solar storm knocked out the power grid in Quebec, causing 6 million people to lose power.
Solar storms can also make global positioning systems less accurate and cause GPS outages.
The storm could trigger communication problems and additional radiation around the north and south poles — a risk that will probably force airlines to reroute flights. Some already have done so, Kunches said.
Satellites could be affected, too. NASA spokesman Rob Navias said the space agency isn't taking any extra precautions to protect astronauts on the International Space Station from added radiation.
NOAA Space Weather Prediction Center: www.swpc.noaa.gov
NASA on solar flare: http://www.nasa.gov/mission_pages/sunearth/news/News030712-X1.5.html
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