Countering the Risks of Human Spaceflight

In January 2004, NASA outlined its human space flight exploration goals, including extended-duration lunar missions by 2015 and Mars surface exploration missions by 2030. These exploration missions will present great challenges, including the possible exposure of crew members to radiation from multiple sources, and unprecedented long-duration confinement, isolation, and exposure to microgravity. To maintain human health and performance in space, NASA must counteract the ill effects of space flight on human health, well-being, and performance.

Image right: Astronaut Edward M. (Mike) Fincke enjoys eating fresh fruit in microgravity.

The actions NASA takes to counteract these effects are countermeasures, in the form of medications, nutritional supplements, use of exercise equipment, and many others. In addition to preventing or minimizing the harmful effects of space flight, countermeasures mus.t also meet strict specifications for use in space, where resources such as storage space and crew time are extremely limited. The goal of NASA's Countermeasure Evaluation and Validation Project (CEVP) is to move countermeasure concepts forward from research activities to effective in-flight countermeasures.

Addressing the Risks

Space flight health risks are identified in the Bioastronautics Roadmap, a comprehensive document developed by NASA to guide research to reduce the risks associated with missions to the International Space Station, the Moon, and Mars. Countermeasures validated by CEVP must address risks outlined in the Bioastronautics Roadmap and ultimately reduce the number and type of these risks to improve crew health and safety.

Image right: Astronaut excercising aboard the International Space Station.

Evaluation & Validation

Countermeasure Development Continuum

All space flight countermeasures must undergo a rigorous process of evaluation in ground-based studies followed by validation in flight before being certified for use by all crew members on space missions.

Investigators associated with the National Space Biomedical Research Institute, Johnson Space Center Biomedical Research Laboratories, and other entities conduct ground-based research to develop promising countermeasure concepts. Researchers and NASA Projects, such as the Exercise Countermeasures Project and the Artificial Gravity Project, do additional tests to find out if the countermeasures are feasible and effective. The potential countermeasures are also evaluated in space flight analog studies, such as bed rest studies sponsored by the Johnson Space Center Bed Rest Project and by the International Partner countries. CEVP monitors the evaluation process to make sure that a steady stream of candidate countermeasures is available for flight testing. Finally, CEVP conducts tests on short- and long-duration space flights to validate the countermeasures to be sure they can be used effectively under space flight conditions.

CEVP uses the Integrated Testing Regimen (ITR), a standard set of biomedical tests, to evaluate the effect of candidate countermeasures on physiological systems. The ITR tests are conducted on all crew members and on all human subjects taking part in flight analog studies. ITR data collected during flight analog studies can be compared with flight crew data to determine which candidate countermeasures should be recommended for flight validation. Candidate countermeasures that are shown to be effective in supporting crew health and performance during flight validation are ready for use during space missions and can be prescribed by flight surgeons.

Putting it All Together

CEVP plays an active role in the on-going management of current countermeasures on the International Space Station (ISS), to maximize the benefit of such measures in light of changing ISS activities and schedules, and to support risk management decisions based on countermeasure data. CEVP also regularly reviews data from crew members to identify gaps in knowledge and to assess the effectiveness of current countermeasures.

With CEVP playing a role in countermeasure evolution, NASA not only improves the well-being of current crews on orbit, but also increases our ability to explore the universe beyond.