Managing Space Radiation Risk in the New Era of Space Exploration (2008)

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A Statement of Task Based on mission requirements (e.g., specific mission architecture and total radiation dose limits) provided by NASA, the committee will evaluate the radiation shielding requirements for lunar missions and recommend a strategic plan for developing the necessary radiation mitigation capabilities to enable the planned lunar architecture. Specifically the committee will: 1. Review current knowledge of radiation environments on the lunar and Mars surfaces, including radiation types, sources, levels, periodicities, and factors that enhance or mitigate levels. Critical knowledge gaps, if any, will be identified. 2. Assess and identify critical knowledge gaps in the current understanding of the level and type of radiation health risks posed to astronauts during various surface activities—ranging from habitation in the CEV to extended exploration sorties and longer stays in exploration outposts—expected for the lunar and martian environments. 3. Review current and projected radiation shielding approaches and capabilities, as well as other exposure mitigation strategies feasible in the lunar and Mars surface environments. 4. Recommend a comprehensive strategy for mitigating the radiation risks to astronauts during lunar surface missions to levels consistent with NASA’s radiation exposure guidelines. The strategy will: — e consistent with NASA’s current timeline for lunar sortie and outpost habitation plans, B — ecommend research to resolve critical knowledge gaps regarding the lunar radiation environment and R risks, — ecommend a research and technology investment strategy that enables development of the necessary R shielding capabilities. 5. The study will provide recommendations on what technology investments (e.g., multifunctional materials, localized shielding, and in situ materials) NASA should be making in preparation for lunar missions, and recom- mend development timelines to ensure NASA has the appropriate level of shielding in place to meet the planned schedules. In developing this strategy for lunar missions, the committee will also consider the likely radiation mitigation needs of future Mars missions and give higher priority to research and development alternatives that will enhance NASA’s ability to eventually meet those future needs. “Critical knowledge gaps” are defined as gaps that prevent the development of any risk mitigation strategy capable of fulfilling mission needs while meeting reasonable criteria (e.g., cost, schedule and effectiveness). 103