The weather isn't limited to what's in the air any more. In fact, it never was. But the weather beyond the atmosphere didn't make much difference in the course of everyday affairs until recently.
Space weather is the interaction between the Sun and Earth's magnetic field. Magnetic storms on the Sun create bursts of energy and particles that stream through the solar system, like this one captured in 2003 by the Cassini spacecraft.
A solar storm bombards Earth's polar regions with higher-than-normal doses of radiation. That forces airlines to divert flights that normally would travel over high northern latitudes, adding hours and costing thousands of dollars in extra fuel.
Storms can also disrupt radio transmissions, and zap orbiting satellites, either knocking them off the air for a while or killing them by frying their electronics.
Especially strong storms can create electric currents all the way down to Earth's surface. These currents can overload power grids, knocking out electricity over large areas. And the biggest storms -- outbursts that the Sun produces perhaps once every few centuries -- could knock out power across entire countries.
One way to mitigate the problems of space weather is the same way to mitigate problems with Earth weather: accurate forecasts. We'll talk about that tomorrow.
Script by Damond Benningfield, Copyright 2011
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