Conceptual Verification of Lunar Long-Duration Method by Using High-Heat-Storage-Capability of Regolith

This paper proposes a lunar long-duration method that uses a characteristic of a very low thermal conductivity of lunar regolith. The principle of this method is to put a heater in at the desired depth of the regolith and heat up the regolith layer during lunar daytime. Because of the very low thermal conductivity of regolith, stored heat in regolith propagates gradually and raises the surface temperature during the cold lunar night. By this method, a lunar lander will be kept warm passively during a cold lunar night. A temporospatially small-scale experimental apparatus that simulates the lunar surface environment was fabricated and the feasibility of a passive thermal control method with no electrical power during lunar nighttime was evaluated. The effectiveness of the proposed method was analytically evaluated by considering the relation between experimental result and actual lunar environment.