Feasibility Study on Handling Lunar Regolith Using Magnetic Force

Abstract

Lunar regolith is magnetic due to the nanophase iron trapped in the surface rim of the regolith. Therefore, technologies are being developed to capture and transport regolith using magnetic force for future in situ resource utilization on the Moon. However, the lack of detailed data on the magnetic properties of regolith hinders the development of efficient regolith handling technologies. Hence, in this study, we conducted experiments to determine the magnetic permeability that would enable the capture and transport of regolith utilizing the magnetic force. A magnetic capture and transport system that utilizes a coil gun principle was developed for this purpose. In addition, we assessed the feasibility of magnetic capture and transport in the low-gravity and vacuum environment of the lunar surface by numerical simulations using the discrete element method. We predicted that the relative magnetic permeability must be higher than approximately 2.0 for magnetic handling of regolith on Earth. However, the magnetic transport of regolith was possible in the lunar environment, even if the magnetic permeability of the lunar regolith was as low as 1.3.