Experts: Solar storm put heat on GPS
CNET ^ | April 5, 2007

A solar eruption in December disrupted the Global Positioning System, a satellite-based navigational system used widely by the U.S. military, scientists and civilians, researchers reported Wednesday.

The solar flare created radio bursts that traveled to Earth, covering a broad frequency range, the researchers said, affecting GPS and other navigational systems.

Solar flares have been known to knock out satellites and even electricity grids, but the researchers said at the Space Weather Enterprise Forum in Washington that this was an unexpectedly serious new effect. "In December, we found the effect on GPS receivers were more profound and widespread than we expected," said Paul Kintner, a professor of electrical and computer engineering at Cornell University.

"Now we are concerned more severe consequences will occur during the next solar maximum," Kintner said in a statement.

Dale Gary of the New Jersey Institute of Technology said the burst created 10 times more radio noise than the previous record had.

"Measurements with NJIT's solar radio telescope confirmed that at its peak, the burst produced 20,000 times more radio emission than the entire rest of the sun. This was enough to swamp GPS receivers over the entire sunlit side of Earth," Gary said in a statement.

Forecasters from the National Oceanic & Atmospheric Administration observed two powerful solar flares on December 5 and 6 of 2006, emanating from a large cluster of sunspots.

A giant radio burst followed, causing large numbers of receivers to stop tracking the GPS signal.

"NASA wants to better understand this solar phenomenon so we can limit the adverse impacts on real-time systems," said Tony Mannucci, a supervisor at the U.S. space agency's Jet Propulsion Laboratory.

Anthea Coster of the Massachusetts Institute of Technology said the findings show that solar radio bursts can have global and instantaneous effects: "The size and timing of this burst were completely unexpected and the largest ever detected. We do not know how often we can expect solar radio bursts of this size or even larger."

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