Summary of Proposal***This proposal addresses physical processes in the region of near-Earth space called the magnetosphere, which is the magnetic cavity surrounding the Earth that is produced in the solar wind by the Earth's magnetic field. Increased occupation (e.g., space stations) and use (e.g., communications satellites) of near-Earth space by humans, and our increasing need for space weather information point to the necessity for understanding the behavior of the magnetosphere. Microphysical processes are studied with a view to understanding how charged particles interact with observed magnetospheric waves. A particular problem to be addressed is the generation of energetic (killer') electrons in the inner magnetosphere during disturbed conditions known as magnetic storms. These electrons can cause satellite malfunctions, and magnetic storms can disrupt power grids on Earth. The science of space weather seeks to describe the state of the space environment and to forecast severe conditions such as geomagnetic storms. Computer modeling and mathematical analysis will be used to study wave-particle interactions in space plasmas. Models will be constructed using particle and wave data from satellite-borne instruments, and the model solutions will be tested against observational data. The proposal is intended not only to advance our basic scientific knowledge of the magnetosphere, but also to advance magnetospheric physics as a predictive science and so benefit society in a broader sense.**