Planetary plasmas and fields



In this presentation I shall dwell on what D. G. King-Hele in his IUGG lecture on Satellite Geodesy has called ‘the unpleasant things that come from the sun with the solar wind.’ Unpleasant they can be, indeed: an astronaut in the wrong orbit through the earth's magnetosphere could be killed in a matter of days by a radiation belt overdose. A journey in a supersonic aircraft flying at stratospheric altitude along the edge of the polar cap during a big solar proton event could have drastic consequences for the passengers' future family planning. The absence of a fully developed protective magnetosphere during geomagnetic reversals in the past probably led to a variety of frightening changes in the upper atmosphere caused by the then unhindered inflow of 1,000,000°K hot solar wind plasma.