Elucidation of spacecraft surface wear phenomena in the plasma environment emitted by electric propulsion vehicles based on spacecraft charging analysis

Professor Takanobu Muranaka, Chukyu University, Japan, is part of a collaborative research effort to investigate and elucidate surface wear phenomena in electric propulsion spacecraft vehicles. He and his team are exploring how injected plasma emitted by these vehicles interacts with the spacecraft, leading to potential electrical and mechanical issues. For example, the ions and electrons in the plasma can collide with the spacecraft, causing wear and tear. This can compromise the spacecraft’s durability and lifespan. In order to analyse these interactions, Muranaka and the team are utilising numerical calculations. To overcome limitations associated with the analysis of spacecraft systems and plasma in space, the researchers perform analyses of objects under predetermined conditions without consideration of space or timescales. Although it isn’t possible to fully replicate space conditions in ground-based vacuum chambers, in their analyses the researchers are able to obtain important raw measurement data on physical phenomena that have not been modelled, such as parameter measurements of electrically propelled plasma plumes. Through its research, the team hopes to contribute to spacecraft design by informing design parameters such as the spacecraft shape and thruster parameters. Ultimately, the researchers are expanding and verifying numerical models and developing advanced plasma interference analysis technologies that will prove invaluable to spacecraft design. The researchers’ investigations on the Hayabusa2 spacecraft’s side-cathode ion thruster system have yielded exciting results on the ion energy distribution function (IEDF) of backflowing ions at multiple points around this thruster, expanding their findings on the significance of thruster reference potential on ion energy distribution, which is key to understanding spacecraft surface erosion.