Utilisation of Moon Regolith for Radiation Protection and Thermal Insulation in Permanent Lunar Habitats

Abstract

In the context of a sustainable long-term human presence on the Moon, solutions for habitat radiation and thermal protection with regolith are investigated. Regolith compression is studied to choose the optimal density-thickness combination in terms of radiation shielding and thermal insulation. The applied strategy is to protect the whole habitat from the hazards of galactic cosmic rays and design a dedicated shelter area for protection during solar particle events, which eventually may be a lava tube. Simulations using NASA’s OLTARIS tool show that the effective dose equivalent decreases significantly when a multilayer structure mainly constituted of regolith and other available materials is used instead of pure regolith. The computerised anatomical female model is considered here because future missions will be mixed crews, and, generally, more sex-specific data are required in the field of radiation protection and human spaceflight. This study shows that if reasonably achievable radioprotection conditions are met, mixed crews can stay safely on the lunar surface. Compressed regolith demonstrates a significant efficiency in thermal insulation, requiring little energy management to keep a comfortable temperature inside the habitat. For a more complete picture of the outpost, the radiation protection of lunar rovers and extravehicular mobility units is considered.

A Survey on Extraterrestrial Habitation Structures with a Focus on Energy-Saving 3D Printing Techniques

“…The regolith found on the Moon and Mars can be applied in both raw and synthesized forms. The raw regolith can be used as a shield layer to protect the outposts from meteoroid impacts, solar radiation [110], and temperature fluctuations. It can also be directly deposited on the outpost and covered with membranes for guaranteeing the stability of the walls.…”

Self-deploying amorphous metal origami structures for environmental protection of lunar payloads

“…Once the scoop was empty, it was refilled and regolith was again deposited from a height of approximately 5 cm above the previous layer of regolith. Prior work in the literature has estimated that a mass per area of 25–30 g/cm 2 of lunar regolith would suffice to reduce the radiation levels for acceptable human exposure, 25–27 this value was used as a first order approximation for the required thickness of regolith for the lunar deployable structure. The required thickness of lunar regolith ( h ) is dependent on the regolith density ( ρ ), and related to the mass per area ( ρ A ) by the equation:…”

Recent Advances and Challenges in Polymer-Based Materials for Space Radiation Shielding

“…The inelastic collisions of neutrons and GCR ions with target atoms in pour hydrogen materials as Al increases the neutrons flux as the shield thicknesses rise. According to the literature, the in situ resource utilization (ISRU) strategy could reduce neutron damage by fabricating composite materials with Martian and lunar RG [98,99]. Zaccardi et al [100] performed simulations about the shielding power of ultrahigh-molecular-weight PE (UHMWPE) composites.…”