Beyond Earth atmosphere, natural space radiation from Galactic Cosmic Rays and Solar Energetic Protons (SEPs) represents a significant hazard to both manned and robotic missions. For lunar settlements, protecting astronauts from SEPs is a key safety issue that needs to be addressed by identifying appropriate shielding materials. This paper investigates the interaction of SEPs with the lunar regolith, and quantifies the effectiveness of the regolith as a biological shield for a human habitat, compared to aluminum, presently the standard shielding material. Also calculated is the shielding thickness to reduce the dose in the habitat to those recommended by International Radiation Protection Committee and by NASA for operation on the international space station. The present calculations are for the most energetic solar event of February 1956, which included high energy protons up to 1000 MeV. Results show that the lunar regolith is as effective as aluminum for shielding lunar outposts. A large thickness of the regolith would be needed to reduce the dose in the habitat from high energy protons below the 30 days flight crew limit of 25 Rem (or 250 mSv) and significantly more shielding would be needed to reduce the dose down to the limit for radiation workers of 5 Rem (or 50 mSv).
Regolith Biological Shield for a Lunar Outpost from High Energy Solar Protons
SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM‐STAIF 2008: 12th Conference on Thermophysics Applications in Microgravity; 1st Symposium on Space Resource Utilization; 25th Symposium on Space Nuclear Power and Propulsion; 6th Conference on Human/Robotic Technology and the Vision for Space Exploration; 6th Symposium on Space Colonization; 5th Symposium on New Frontiers and Future Concept ; 2008 ; Albuquerque (New Mexico)
AIP Conference Proceedings ; 969 , 1 ; 474-483
2008-01-21
10 pages
Conference paper
Electronic Resource
English
A Sustainable Regolith-Based Water Recovery Concept for the Lunar Outpost
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