bild

Northern lights. Rare burst of red northern lights, or aurora borealis, over Lake Wateree, South Carolina, USA. The aurora was triggered on 29 October 2003 during a severe geomagnetic storm produced by one of the most powerful solar flares ever recorded. A solar flare occurs when charged particles in the solar atmosphere are rapidly released as solar wind. The solar wind, channeled by the Earth's magnetic field, collides with the Earth's atmosphere at the north and south poles, causing a release of energy seen as coloured lights (aurora) in the sky. (KEYSTONE/SCIENCE PHOTO LIBRARY/JIM REED) === ===