Beam–Spacecraft Plasma Interaction and Charging Experiment

The use of high-power electron beams in low-density space environments could open a wealth of new opportunities in magnetospheric science and help answer several fundamental, outstanding questions. However, emitting a sufficiently high-power electron beam in a low-density plasma environment induces a charge on the spacecraft that inevitably leads to beam return. One promising solution is the use of a plasma contactor to produce a dense plasma cloud capable of emitting sufficient ion current and overcoming traditional space charge limits. Furthermore, numerical simulations predict scaling laws for spacecraft charge neutralization when operating a plasma source and electron beam simultaneously in a low-density plasma environment. Beam–Spacecraft Plasma Interaction and Charging Experiment, launched in November 2024, is presented as an investigation of this plasma contactor strategy for mitigating spacecraft charging. The data demonstrate the ability of a charge-neutral plasma source to counteract electron-beam-induced spacecraft charging in flight. This paper details the payload, concept of operations, and initial findings from the mission.