Radiation belt storm probes: Resolving fundamental physics with practical consequences

The fundamental processes that energize, transport, and cause the loss of charged particles operate throughout the universe at locations as diverse as magnetized planets, the solar wind, our Sun, and other stars. The same processes operate within our immediate environment, the Earth's radiation belts. The Radiation Belt Storm Probes (RBSP) mission will provide coordinated two-spacecraft observations to obtain understanding of these fundamental processes controlling the dynamic variability of the near-Earth radiation environment. In this paper we discuss some of the profound mysteries of the radiation belt physics that will be addressed by RBSP and briefly describe the mission and its goals. ► Physical mechanisms of acceleration and loss or radiation belt particles remain a mystery. ► NASA RBSP mission will provide physical understanding of radiation belt variability. ► RBSP consists of two spacecraft which will resolve spatial and temporal variability of the belt. ► RBSP instrument payload provides unprecedented set of particle and field measurements.