Satellite measurements of the Earth`s magnetosphere promise better space weather forecasts
(PHYSorg.com Space & Earth)

Earth is constantly being hammered by charged particles emitted by the sun with enough power to make life on Earth almost impossible. Life is only possible because Earth`s magnetic field traps and deflects these particles, preventing the vast majority of them from ever reaching the planet`s surface. The trapped particles bounce back and forth between the North and South poles in complex, ever-changing patterns that are also influenced by intricate and shifting electric fields. When the Van Allen radiation belts in which they travel dip into the atmosphere near the poles, they create the Northern (and Southern) lights. Bursts of these particles can also damage satellites and sensitive equipment on the ground.