The Earth's magnetosphere, created by interaction between the solar wind and the terrestrial magnetic field, is a natural plasma laboratory which hosts a remarkable variety of physical phenomena occurring on a range of length scales from tens of Earth radii down to tens of meters. This presentation will provide a brief introduction to magnetospheric physics and some of the modeling techniques used to describe it.
One of the interesting processes in magnetospheric physics is the generation of highly energetic electrons which represent a significant danger to satellite electronics as well as to astronauts. A mechanism for producing high-energy electrons by wave acceleration will be discussed, as well as a technique allowing to use magnetospheric waves for remote sensing of the Earth's magnetosphere. The talk will conclude with a discussion of cosmic rays, another source of radiation in space, and of some of the implications of the recent solar minimum which was unusually deep and long.