We've learned that the solar wind travels past the Earth at well over 1,000,000 miles per hour. And thanks to the Earth's magnetic field, the solar wind is stopped and deflected around the Earth so that most of it does not hit our atmosphere head on.

Ultra-violet rays from the sun ionize the upper atmosphere, creating the electrically-conducting ionosphere and a source of plasma for the magnetosphere. The energy from the solar wind enters the magnetosphere and is stored there, being released in sudden surges.

Our neighboring planet, Mars, which has little or no magnetic field, is thought to have lost much of its former oceans and atmosphere to space. This loss was caused, at least in part, by the direct impact of the solar wind on Mars' upper atmosphere. Our other close planetary neighbor, Venus, has no appreciable magnetic field, either. Venus is also thought to have lost nearly all of its water to space, in large part owing to solar wind-powered ablation.