Magnetospheric Cold Plasma Diagnostics Using High Altitude GNSS Signals

Abstract The plasmasphere is a key component of Earth's magnetosphere, regulating numerous energy transfer processes. The plasmasphere is also a cold multi‐species plasma. Tracing differences in dynamics between low and high mass cold ions is important for identifying the processes that drive plasmaspheric evolution. At the same time, measurements of cold ion fractional composition within the plasmasphere are sparse and challenging to obtain. Seeking to overcome this challenge, this work presents a novel concept for combining extreme ultraviolet (EUV) photon imaging and Global Navigation Satellite System (GNSS) pseudorange observations to measure cold ion fractional composition throughout the plasmasphere. The feasibility of this concept is demonstrated using a model plasmaspheric density structure combined with known properties of GNSS transmitters and signals. Implementation of this measurement concept on a future space mission has the potential to enable significant new progress understanding processes that drive plasmaspheric and, extension magnetospheric dynamics.