On the Theory of Magnetic Storms and Aurorae

A. Chapman-Ferraro’s theory of magnetic storms is discussed. It is pointed out that the fundamental assumption about a non-magnetized beam is in conflict with cosmic ray evidence. It is further shown that there is a fundamental objection against any theory of the main phase based on a non-magnetized beam.B. The objections, which Cowling and Chapman have raised against the electric field theory, are discussed, and the discharge mechanism during a magnetic storm is analysed. When a magnetized beam enters the earth’s magnetic field, it is heated due to the compression. In the hot plasma the earth will act as a “probe” so that it gets a negative charge in relation to the plasma. As a result of ambipolar diffusion to the earth, the ionosphere in the auroral zones will be bombarded by high energy protons and electrons.It is shown that a mechanism of this type is not subject to the objections which have been raised.