DENVER -- A geomagnetic storm spawned by a giant eruption of gas on the sun reached the Earth's upper atmosphere on Friday, interfering with high-frequency airline communications but causing no major problems, federal officials said.
The storm was expected to be most severe Friday, although experts said it would last for up to two weeks.
"This is not a super solar storm," said Larry Combs, a space weather forecaster with the National Oceanic and Atmospheric Administration's Space Environment Center in Boulder.
So far, the storm has interfered with airline communications and radio communications for teams on Mount Everest, Combs said. But problems were not widespread.
The storm, called a "coronal mass ejection," is a mass of solar gas that swept toward Earth at 2 million mph. The usual cycle for such a storm is every 11 years; this one was expected to hit three years ago.
"It is kind of like a snowstorm in June in Colorado," Combs said.
Combs said power companies have been notified and were taking precautions to avoid voltage problems and blackouts.
"We will be watching our transmission system very closely 24 hours a day," said Steve Roalstead, spokesman for Xcel Energy, a major Western power provider.
The storm's most visible effect will be the beautiful shimmering light displays, called auroras, that are visible to the naked eye right after dark, said Dale Gary, professor of physics at the New Jersey Institute of Technology.
On the Net:
Space Environment Center: http://www.sec.noaa.gov