Electric Thruster Modeling And Its Influence On Spacecraft Charging In Varied Plasma Environments

Abstract

As spacecraft travel through space, they encounter various charged particles, including ambient ions, electrons, photoelectrons, and secondary electrons. These particles, collected and emitted by the spacecraft, cause it to accumulate a positive or negative voltage to maintain current equilibrium. However, excessive charging can lead to hazardous surface charging from electrons and ions with energies below 10-100 keV, and deep dielectric charging from electrons with energies above 100 keV, resulting in discharges that pose significant operational challenges. Another source of charging occurs during electric thruster operation, where Charge Exchange (CEX) ions and thruster electrons interact with the spacecraft surface and solar panels, raising scientific and operational concerns. Additionally, the findings apply to electric propulsion missions in interplanetary exploration missions that utilize Hall-effect or ion thrusters. Thus, the thesis aims to investigate the effects of electric thruster-induced charging on spacecraft potential under varying ambient plasma and solar photon conditions, comparing scenarios with and without thruster operation. The main research question is whether the spacecraft’s negative charging induced by electric thrusters varies with changing ambient plasma and solar-photon flux conditions and whether ambient plasma particles and solar photons amplify or alleviate negative charging.