Figure 2-1 summarizes the committee’s analysis of the BR’s proposed deliverables. An analysis of the forward work required to complete the BR risk mitigation plan reveals that 50 (27%) of the 183 proposed countermeasures and technology modifications are not yet defined. Of those that were defined, 71 (53%) are at the basic research stage of development (CRL or TRL levels 1–3), 56 (42%) are in the ground testing stage of development (CRL or TRL levels 4–6), and 6 (5%) have reached some stage of flight evaluation (CRL or TRL levels 7–9). Thus, more than half of the defined deliverables proposed in the BR rank below the stage 4 level of readiness and, thus, below the threshold for priority in bioastronautics research consideration. Included in these unranked or low-readiness areas are substantial portions of the mitigation plans on behavioral health and performance, radiation, autonomous health care, and water quality monitoring, areas that the committee finds deserving of further attention from NASA (IOM, 2005). To summarize, the state of countermeasure development significantly lags the need.
The committee finds that the majority of projected BR countermeasures, mitigations, or other deliverables are in a nascent state of readiness and are therefore unlikely to receive high-priority attention. Resources (described in Chapter 4) are unlikely to be sufficient to complete the BR mitigation plan in a time frame that enables the exploration class missions envisioned by NASA.
Establishing priorities for in-flight studies will be a significant challenge. Since NASA must address both near-term (e.g., the proposed lunar mission) and long-term (e.g., the Mars mission) objectives, the priorities for access to investigations aboard the ISS will require considerable wisdom to ensure that urgency is not confused with importance. Thus, some apparently “lower-priority” investigations may need to be manifested on the ISS earlier than others that might appear to be of higher priority. For example, studies regarding bone loss may have to take priority on the few remaining ISS flights in order to generate adequate in-flight data to support the Mars mission because countermeasures to bone loss will clearly be essential on a 30-month mission, even though that mission may be many years hence.
With the increasing likelihood that crew time, up-mass, and manning will continue to be problematic aboard the ISS, it will become increasingly important for surrogates of some sort to be used or developed to help assess the medical, nutritional, environmental, and behavioral issues that may confront astronauts who are in conditions of high stress in tight quarters for an extended period of time. The committee believes that analog environments and digital simulation will play an increasingly important role in