First Full Mapping of Near-Earth Plasma Transport Achieved, Thanks to the Van Allen Probes

Maps are developed to best describe what surrounds us. That is true on the ground, and it is also true in space. To detail traffic in space, we must know both the magnetic field and the electric field: how strong are they? In what direction are they pointing? But unlike the magnetic field, the electric field is very difficult to measure, especially close to Earth! Using data from the Van Allen Probe satellites, we managed to make the first ever comprehensive observations of plasma transport due to the electric field close to Earth. This is a technical feat that allows us to test our 50 year old theories, at last!