The article “Utilisation of Moon Regolith for Radiation Protection and Thermal Insulation in Permanent Lunar Habitats” was published in 2021 and indexed by DOAJ; it reports simulations using NASA’s OLTARIS radiation tool comparing pure regolith shielding with multilayer structures made mainly of regolith plus other available materials.[2] The key result is that effective dose equivalent drops significantly when regolith is combined in a multilayer system rather than used alone.[2]
The technical implication is that pure regolith is not the optimal single-material shield for permanent habitats: layering regolith with complementary materials improves radiation performance and likely helps with thermal insulation as well.[1][2] For lunar habitation, this points to hybrid wall architectures rather than simple berms or thick monolithic regolith covers, because dose reduction matters directly for crew health, mission duration, and long-term infrastructure resilience.[1][2]
The Ark should treat this as a design requirement for habitat shells, not an academic curiosity: prioritize hybrid shielding stacks, benchmark them against OLTARIS-style transport models, and test configurations that combine regolith mass with hydrogen-rich or other interior liners.[2] Monitor follow-on work on optimal density-thickness combinations, because the best solution is likely a layered system tuned for both radiation attenuation and thermal control rather than maximum regolith thickness alone.[1][2]