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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