GPS May Falter When Solar Winds Blow
The satellite-based Global Positioning System was seriously disrupted in December 2006 by a solar storm, experts reported on Wednesday. The unexpected solar radio burst on Dec. 6 affected nearly all GPS receivers on the lighted half of Earth, according to the National Weather Service.
04/05/07 10:28 AM PT
A December 2006 geomagnetic storm from the sun wreaked havoc on the Global Positioning System (GPS), a satellite-based navigational system used widely by the U.S. military, scientists and civilians, researchers reported Wednesday.
The solar storm interfered with a variety of technologies including wireless communications networks.
The GPS is used in everyday applications from flying airplanes to transferring money to helping drivers navigate cars.
"Our increasingly technologically dependent society is becoming increasingly vulnerable to space weather," David L. Johnson, director of the National Weather Service (NWS), said.
The unexpected solar radio burst on Dec. 6 affected nearly all GPS receivers on the lighted half of Earth, according to the NWS.
Solar flares have been known to knock out satellites and even electricity grids, but the strength of this outburst surprised researchers.
"This reading is more than 10 times the previous record and calls into question scientists' assumptions of the extent to which the sun can interfere with GPS and wireless communications," Dale Gary, a professor and chair of the department of physics at New Jersey Institute of Technology, told TechNewsWorld.
Reports of significant events worldwide were still being reported as late as yesterday afternoon, Gary said.
"The solar flare created radio bursts that traveled to the Earth, covering a broad frequency range, affecting GPS and other navigational systems," he noted.
Because of a computer software failure, initial research reports in the U.S. downplayed the outbursts, according to Gary.
Protecting the GPS system from the sun would be very costly and difficult given the sometimes unpredictable nature of solar explosions, according to Gary.
One possible way to shield the system would be to alter all GPS antennas to screen out solar signals, he said. Another possible solution: replace all the GPS satellites with ones that broadcast a stronger signal.
"The problem now is you cannot shield from something that is the same frequency," said Gary.
Solar activity rises and falls in 11-year cycles with the next peak expected in 2011, but the Earth can expect significant solar disruptions beginning in 2009, he concluded.