Better Predictions of Space Weather

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Kaiser says that because satellites depend on microelectronics, they are very sensitive to small changes in current and voltage. Magnetic disturbances from CMEs can wipe out satellite computers' memory. Luhmann says severe CMEs can actually shift the Earth's magnetic field, leaving satellites orbiting above the equator outside the field.

Satellites orbiting in interplanetary space, outside the Earth's protection, get a high dose of radiation during a CME; their solar panels are usually degraded. Kaiser cites a two-week period in 2003, called the Halloween storms, during which 20 CMEs, including some of the biggest ever recorded, damaged "almost every spacecraft."

Solar storms can also affect the transmission of radio waves through the ionosphere, which can corrupt GPS signals. Kaiser says the oil industry is very interested in space weather prediction because it relies on GPS to guide offshore drilling. "If there's a solar storm in process...their GPS could be off," he says. CMEs can also cut off airplanes' radio contact when flying over the poles, as many long international flights do. When CMEs are predicted, airlines must reroute on short notice.

With warnings further in advance, says Kaiser, satellite operators "could power down or standby [their satellites]. It's like turning off the TV during a lightening storm."