POSITION PAPER Human Health and Performance for Long-Duration Spacefl ight Ad Hoc Committee of Members of the Space Medicine Association and the Society of NASA Flight Surgeons A D H OC C OMMITTEE OF M EMBERS OF THE S PACE M EDICINE A SSOCIA- 1. Fulfi ll our human nature to explore the unknown beyond the TION AND THE S OCIETY OF NASA F LIGHT S URGEONS . Human health and bounds of our planet, with extended missions to the Moon pro- performance for long-duration spacefl ight. Aviat Space Environ Med viding the operational training ground for future planetary out- 2008; 79:629 – 35. posts such as Mars; Future long-duration spacefl ights are now being planned to the Moon 2. Establish a permanent Moon outpost to conduct experiments and Mars as a part of the “ Vision for Space Exploration ” program initi- and studies to answer questions about how the solar system was ated by NASA in 2004. This report describes the design reference mis- formed and is evolving. The Moon, devoid of any atmosphere, is sions for the International Space Station, Lunar Base, and eventually a an ideal site for such astronomical observations and research Mars Expedition. There is a need to develop more stringent prefl ight and the necessary fi rst step for the development of a planetary medical screening for crewmembers to minimize risk factors for diseases outpost; which cannot be effectively treated in fl ight. Since funding for space life 3. Develop commercial operations such as mineral mining and mi- sciences research and development has been eliminated to fund pro- crogravity materials development; gram development, these missions will be enabled by countermeasures 4. Improve international cooperation among nations and inspire much like those currently in use aboard the International Space Station. the commonality of cultures; Artifi cial gravity using centrifugation in a rotating spacecraft has been 5. Inspire young people to pursue careers in science and engineer- suggested repeatedly as a “ universal countermeasure ” against decon- ing; and ditioning in microgravity and could be an option if other countermea- 6. Eventually extend the settlement of humankind and preserve sures are found to be ineffective. However, the greatest medical unknown our species from extinction due to a catastrophic asteroid event or eventual sun death. in interplanetary fl ight may be the effects of radiation exposure. In addi- tion, a Mars expedition would lead to a far greater level of isolation and Carrying out this vision will challenge the medical pro- psychological stress than any space mission attempted previously; be- cause of this, psychiatric decompensation remains a risk. Historically, fession to protect the human crewmembers from the mortality and morbidity related to illness and injury have accounted for hostile environments of interplanetary space and the more failures and delays in new exploration than have defective trans- surfaces of the Moon and Mars, and to provide the best portation systems. The medical care system on a future Mars expedition medical care possible on these remote journeys. will need to be autonomous and self-suffi cient due to the extremely long separation from defi nitive medical care. This capability could be ex- Future design reference missions (DRMs) for the step- panded by the presence of a physician in the crew and including simple, wise exploration of space are listed in Table I with target low-technology surgical capability. dates. These DRMs will require remote space outposts on the International Space Station (ISS), Lunar, and Mars Outposts and illustrate the daunting tasks ahead. N JANUARY 14, 2004, the United States put forth a Outposts on the lunar surface will be several days O Vision for Space Exploration, setting a long-term away from Earth, and both medical personnel and direction for the return of humans to the Moon, followed by robotic and human exploration of Mars. This vision is bold and forward-looking, yet practical This Position Paper was adopted by the Aerospace Medical Associa- tion. The following members of the Space Medicine Association and and responsible – one that explores answers to long- the Society of NASA Flight Surgeons contributed to this report: Drs. standing questions of importance to society, develops Denise L. Baisden, Gary E. Beven, Mark R. Campbell, John B. Charles, revolutionary technologies and capabilities, fosters Joseph P. Dervay, Estrella Foster, Gary W. Gray, Douglas R. Hamilton, Dwight A. Holland, Richard T. Jennings, Smith L. Johnston, Jeffrey A. international cooperation and scientifi c exchange for Jones, Joseph P. Kerwin, James Locke, James D. Polk, Philip J. Scarpa, the future, while maintaining good stewardship of Walter Sipes, Jan Stepanek, and James T. Webb. taxpayer dollars. The specifi c reasons for taking the This Position Paper is intended to update the membership of the necessary steps of extended microgravity stays on the Aerospace Medical Association on the current plans for Long-Dura- tion Spacefl ight (specifi cally Lunar Outpost and Mars expedition). As International Space Station and then extended stays on detailed plans are dynamic and evolutionary, there was an attempt to the Moon to achieve a planetary outpost were recently concentrate on general concepts. delineated by NASA at a conference held in Houston, This manuscript was received for review in March 2008 . It was ac- TX, organized by the American Institute of Aeronau- cepted for publication in April 2008 . Reprint & Copyright © by the Aerospace Medical Association, Alex- tics and Astronautics. These are summarized in the andria, VA. following: DOI: 10.3357/ASEM.2314.2008 Aviation, Space, and Environmental Medicine x Vol. 79, No. 6 x June 2008 629 SPACEFLIGHT & HUMAN HEALTH—SMA & SNFS TABLE I. CHARACTERISTICS OF SELECTED DESIGN REFERENCE MISSIONS (DRM). 1-yr ISS Lunar Mars DRM Crew Size 2 1 46 Launch Date 2010 2018-2020 2025-2030 Mission Duration 1 yr 10-44 d 30 mo Outward Transit 2 d 3-7 d 4-6 mo On-site Duration 1 yr 4-30 d 18 mo Return Transit 2 d 3-7 d 4-6 mo 1-way Communication Lag 0 1 1.3 s 1 3-20 min g Transitions 2 4 4 Hypogravity 0 g 1/6 g for 30 d 1/3 g for 18 mo Spacecraft Internal Environment 14.7 psi 21% O2 TBD TBD EVA Schedule 0-4 per mission 2-3 per week ; 4-15 EVA per person 2-3 per week ; 180 EVA per person Deep Space Radiation Exposure ; 0 ; 6-14 d ; 8-12 mo equipment will be quite limited. But on travel to Mars, Life Support and Habitability these limitations will be multiplied; crews and their sup- Mission designers are well aware of the challenges of plies will be absent from Earth with no possibility of providing a safe, extremely reliable, and habitable envi- rapid return for many months at a time. Competition for ronment during extended space missions. Their efforts space and weight will require state-of-the-art monitor- will involve trading off these considerations with weight, ing, diagnostic, and treatment hardware, while limiting power, volume, and other operational requirements. the training needed to use it. This is the ultimate chal- One example is the pressure and composition of the at- lenge to the concept of telemedicine, which was fostered mosphere chosen. Here, the safe medical choice must by NASA, and must evolve into real-time, simulator- compete with engineering and logistics factors (e.g., leak based, onboard instruction and training. It will also rate, mass and volume of gases, fl ammability, and equip- push the envelope in the principles of preventive medi- ment cooling) and the need to protect the crew from de- cine and necessitate the development of screening tech- compression illness during EVA (extravehicular activ- niques beyond the present scope and capabilities. ities). The space medicine community must not only This paper will summarize the views of a panel of provide valid medical requirements but must work very members selected from the Space Medicine Association closely with the designers and operators as the space- (an Aerospace Medical Association constituent organi- craft are developed and tested, participating in any nec- zation) and the Society of NASA Flight Surgeons (an essary compromises. AsMA affi liate organization) on the vision’s principal challenges to space medicine and the approaches to meeting them. Specifi cally these include the critical life Microgravity Countermeasures science technologies and capabilities needed in the areas Countermeasures are under development to mitigate of medical screening risk mitigation, life support and the risks of prolonged spacefl ight on the human body. habitability design, and microgravity countermeasures Some of these countermeasures may be pharmacologi- and health care. cal, and may have side effects and/or risks of their own. In any event, residual medical risks will always remain. Pre-Mission Medical Screening The nature of such risks will vary, from short-term illness The fi rst step in the medical risk mitigation for mis- or injury, which cannot be treated during the mission, to sions to Moon and Mars will require a signifi cant effort permanent tissue and organ damage (e.g., from radia- in research and development in primary prevention tion or bone demineralization) which may result in mor- screening capabilities. There needs to be an inverse rela- bidity and mortality during the mission or later in life. tionship between access to medical care and the physi- Because of their experimental nature, space counter- cal qualifi cations demanded of explorers. In planetary measures will not have been subject to the lengthy and exploration, the rigors and unknowns of the environ- very extensive testing for safety and effi cacy that the ment amplify this relationship. Medical standards for Food and Drug Administration requires to certify al- travelers to the Moon, and most especially to Mars, most all treatments (e.g., drugs, surgical procedures, should utilize the latest screening methods to minimize etc.) for use in the general population.