The benefits gained from pursuing these strategies will be not only a reduction by a factor of 2 or more in the uncertainty in estimates of the risk of late effects for crew members exposed to radiation in space, but also greater understanding of CNS and other effects about which little is currently known. These benefits will result in a narrowing of the scope of the types and designs of shielding that need to be considered for crew protection, and thus should result in a significant cost savings. The liability of following these strategies is that the time required to complete them may delay a decision on shielding design and consideration of any near-term (within 25 years) launch dates if suitable resources are not made available to complete the research expeditiously.
Since these research strategies are narrowly focused and based entirely on current understanding of space radiation issues, there is also no guarantee that this approach will necessarily address all of the significant radiation hazards for crews of deep-space missions. Utilizing a wider range of radiation and biological models could lead to recognition of previously unappreciated hazards for those crews and reveal useful new avenues of research.
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