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POSITION PAPER

Human Health and Performance for Long-Duration Spacefl ight

Ad Hoc Committee of Members of the Association and the Society of NASA Flight Surgeons

AD HOC COMMITTEE 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 SOCIETY OF NASA FLIGHT SURGEONS . Human health and bounds of our planet, with extended missions to the 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 ; 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 ” program initi- and studies to answer questions about how the 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 , 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 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 death. in interplanetary fl ight may be the effects of 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 put forth a Outposts on the lunar surface will be several days O Vision for Space Exploration, setting a long-term away from , and both medical personnel and direction for the return of humans to the Moon, followed by robotic and human . 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 . These are summarized in the andria, VA. following: DOI: 10.3357/ASEM.2314.2008

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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. This is acceptable risk factors for diseases which cannot be effectively because the countermeasures are not to be used in the treated during the missions. Chronic diseases for which general population. They are considered to be experi- medication is required on a regular basis might be dis- mental (off label use), yet they will be taken and used by qualifying as they would affect the total volume of the informed subjects. Safety and effi cacy will be tested, but medical care system adversely. Genetic factors, which on smaller numbers of subjects and in analog environ- predispose crewmembers to disease, must be taken into ments as well as in space. consideration. This is currently undefi ned, but is ex- Due to the limitations placed on such testing, there pected to become more important in the future as re- will be a necessity to accept countermeasures that, at the search in this area is rapidly progressing. time, are not fully developed, and thus are neither as

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effi cient nor effi cacious as might otherwise be possible. make radiation therapy, nuclear reactors, and other haz- It is expected that the countermeasure effectiveness ardous environments on Earth safer. will be routinely monitored on lunar and Mars expedi- Artifi cial gravity countermeasures: Exposure of the tion missions to insure maximum benefi t to the crew- crew to “ artifi cial gravity, ” that approximates Earth- member. This will also permit continued refi nement normal gravity loads, via centrifugation in a rotating of the various countermeasure modalities. Thus, the spacecraft has been suggested repeatedly as a “ universal complete countermeasure development will actually be countermeasure ” against deconditioning in micrograv- deferred into the operational setting, with expected re- ity. Such an approach has profound and extensive engi- sulting impacts on mission resources and countermea- neering implications, and current mission scenarios do sure improvements. not incorporate it. Furthermore, the proposed benefi ts Countermeasure testing will be limited because of are unproven. However, it is worth the effort to deter- practical, and perhaps unavoidable, decisions made in mine whether artifi cial gravity “ works, ” what g levels the early years after the pronouncement of the Vision for are necessary, and what rotation velocities are acceptable. Space Exploration. The requirement to develop a crew- Such a determination will provide both fundamental carrying spacecraft as a replacement for the Space Shut- knowledge of biological processes and a valuable insur- tle, in parallel with continued and Interna- ance policy against unacceptable risks from exposure to tional Space Station operations, all without a signifi cant . We endorse ground-based and, if possi- increase in overall NASA funding, necessitate other por- ble, space-borne studies of animals in a centrifuge large tions of the NASA’s program— including space life sci- enough to provide continuous exposure to a variety of g ences research and development— to bear the sacrifi ce. levels. We also endorse human experiments on a short- The deferred research and development would have in- radius centrifuge, both on the ground and in a space- cluded a larger suite of more effi cient and effective craft. Eventually, prolonged habitation on the Moon will physiological countermeasures. These countermeasures expose to 1/6 th of Earth’s surface gravity for especially include those which might have developed weeks or even months, permitting detailed study of hu- from the low technical readiness level (TRL) activities man physiological responses to extended exposure to and which might have borne fruit in later years had they an additional gravitational environment (the two others not been preferentially targeted for reduction or elimina- being Earth’s surface gravity and weightlessness). It is tion. Thus, NASA’s Lunar Outposts and eventual Mars important to endorse provisions to acquire this knowl- missions will most likely be enabled by countermeasures edge on the Moon during the course of lunar missions, and protocols not fundamentally different from those to benefi t future planetary surface architecture planning currently in use aboard the International Space Station. and design of future deep-space vehicles. The eliminated research would have investigated the physiological mechanisms underlying the potentially deleterious changes observed in crewmembers during In-Flight Medical Care long-duration spacefl ight. The study of these physiologic Medical care arrangements on the lunar surface for the adaptive mechanisms of spacefl ight would have created longer duration Lunar Base missions should include the the opportunity to devise risk mitigation measures that presence of a physician; and on a Mars expedition mis- could have served to maintain, restore, or enhance phys- sion, depending on crew size, having two physicians iologic function of the crew. In the absence of either his- should be seriously considered and surgical training torical or contemporary insights into the mechanisms of should be mandatory. As complete a suite of monitoring these deleterious changes, mission designers are forced and diagnostic equipment as technology can provide to make decisions for future operational support based should be onboard. This capability should provide for on imprecise and incomplete knowledge. thorough periodic evaluations of crew health and will Radiation: The greatest medical unknown in interplan- double as experiment equipment. This mission will be etary fl ight may be the quality, intensity, and effects of one of great medical signifi cance, and should be planned radiation. A radiation shelter can afford protection to yield a comprehensive set of medical data. The benefi ts against occasional solar fl ares. However, sheltering of increasing the capability of the medical care system are against extremely energetic “ galactic cosmic radiation” obvious. The risks of not having enough capability in- may be impossible and even harmful, due to the biologi- clude mission abort, not being able to accomplish the cal effects of a large number of secondary particles gen- goals of the mission, and in-fl ight morbidity and mortal- erated by interaction of a few energetic primary (such as ity. There are also risks as the capabilities (hardware and Galactic Cosmic Radiation or GCR) particles with the crew training) are increased as they will affect other as- atoms in the shielding. NASA and its international part- pects of the mission. The volume, weight, power require- ners have embarked upon an aggressive program of re- ments, and crew training time are all severely limited. search and measurement to characterize this radiation Any additional capability in one area (the medical care more accurately, and to estimate better its threat to hu- system) will require decreased capability in another area. man health. Physicians, physicists, and materials experts Our clinical experience in space at this time is very will work together to reduce the risk for space explora- limited and a surgical procedure has never been re- tion, with the prospect that improved knowledge and quired or performed during spacefl ight. However, there understanding of shielding techniques will also help to will be a rapid increase in both crew size and mission

Aviation, Space, and Environmental Medicine x Vol. 79, No. 6 x June 2008 631 SPACEFLIGHT & HUMAN HEALTH—SMA & SNFS duration with the exploration class missions to follow, reach defi nitive medical care is only 24 to 36 h for the In- and with it the likelihood of surgical events will increase. ternational Space Station, but is 4 to 7 d for a Lunar Base Current weight and volume restrictions on spacecraft and over 9 mo for a Mars expedition. severely limit the availability of surgical and anesthetic The minimal capabilities for the International Space equipment to cover all but the most likely situations. Station, Lunar outpost, and Mars mission are listed in Due to limits on crew size and capabilities, it is currently Table II . not possible to have crew medical offi cers with the nec- The paradigm for the surgical component of the med- essary intensive training to handle major surgical proce- ical care system for long-duration fl ight is not a highly dures. A signifi cant surgical event will greatly impact technological system (such as robotic surgery with the mission and require a large amount of resources in stored memory), ultra sophisticated hardware, or surgi- order to be treated successfully. cal procedures which require specialized training. In- Historically, mortality and morbidity related to illness stead, the paradigm is more likely to resemble the surgi- and injury have accounted for more failures and delays cal care of the 1960s. It was not uncommon then for a in expeditions and new exploration than have defective general practitioner to perform an appendectomy, a cho- transportation systems. There are numerous ways in lecystectomy, or even more advanced surgical proce- which the environment of a long-duration spacefl ight dures. The Crew Medical Offi cer will need to be skilled such as a Mars expedition will affect the ability to pro- in many areas and yet also be as surgically capable as vide medical and surgical care. These include long com- the common family doctor of the past (in the 1960 era, munication delays (8 to 56 min depending on the orbital these physicians commonly performed open abdominal confi guration of the Earth and Mars), limited medical cases). The experience onboard the International Space care resources, the abnormal pathophysiology of space- Station has shown that hardware will need to be simple fl ight, limited crew training and experience, radiation and reliable, or at least easily repairable. Advanced tech- exposure, operating in an enclosed environment, and nology hardware that has a high failure rate or a low long defi nitive medical care times. The medical care sys- rate of maintainability will be a liability. It is very hard tem on a future Mars expedition will need to be very au- to break a hemostat, a scalpel, or a pair of scissors. tonomous and self-suffi cient due to the extremely long There will be an increased emphasis on converting sur- separation from defi nitive medical care. The time to gical conditions to medical illness. Examples include dis-

TABLE II. PROJECTED MEDICAL CAPABILITIES FOR AND BEYOND.

Advanced Life Support Capabilities Time to Defi nitive Medical Care Crew Medical Offi cer Training Low Earth Orbit (LEO) / ISS 24 h Specialized Restraint Systems Trained EMT ( , 100 h training) IV/IM Medications Oral & Endotracheal Airway / Cricothyroidotomy Automated Pneumatic Ventilator BP Monitoring Pulse Oximetry

Ultrasonography (Abdominal, Cardiac, Thoracic) Paramedic Level (2) Informatics/Telemedicine Limited Hyperbaric Treatment Defi brillator with External Cardiac Pacing ECG Monitoring Modifi ed ACLS & ATLS Protocols Minor Surgical Care

Lunar Base Missions / Stable Lagrangian Platforms Days to weeks LEO / ISS , plus augmented supplies: Physician & Paramedic or More sustainable ACLS and ATLS Paramedic & Paramedic with Advanced Training Hyperbaric Chamber Advanced Diagnostic Tools Diagnostic Imaging (?) Radiation Shelter

Mars Expeditionary Missions 9 to 30 mo Lunar, plus augmented supplies and Physician (limited surgical capability) stand-alone capabilities: & Paramedic IV Fluids, Antibiotics, and Nutrition Limited Surgical Intervention Banked or Synthetic Blood / Banked Bone Marrow Informatics/Expert Systems/Clinical Decision-Support Tools Radiographic / MRI Diagnostic Imaging Recuperation and Convalescence Capabilities Radiation Shelter

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solving urinary or biliary calculi, percutaneously draining Such communication challenges will also mandate the fl uid collections (such as an intra-abdominal abscess), existence of an autonomous method of psychological/ treating an ectopic pregnancy with Methotrexate, and psychiatric self assessment and diagnosis for disorders treating malignancies (such as breast cancer) nonsurgi- of mood, anxiety, thought, cognition, and level of fa- cally until return to Earth. Prophylactic surgery (cholecys- tigue. A comprehensive battery of self-administered or tectomy or appendectomy) will be considered, but repre- crew medical offi cer- (CMO) administered psychologi- sent preventing specifi c diseases of low incidence instead cal diagnostic tests will be required. The results of providing for general medical/surgical capabilities. may then be sent to the crew surgeon and the ground The requirement to limit mass, volume, power, and consultant psychiatrist/psychologist for review and rec- onboard medical expertise will be judiciously traded off ommended therapeutic response. In this regard, the with the need for comprehensive medical and surgical CMO will require a much greater level of training in be- care capability including the need for operative inter- havioral medicine issues than is currently required for vention. A system with more surgical capability than has Low Earth Orbit (LEO) missions. A computer- delivered, been present in past space medical care systems will be interactive, self-guided psychotherapy tool to aide in the necessary due to the increased risk and the need to re- treatment of depression, anxiety, and interpersonal con- duce mission and health impact. This capability may be fl ict would also be highly benefi cial. Antarctica, provided through a mixture of traditional resources and the ISS, and long-duration lunar missions would pro- some newer innovative technologies currently in vide venues for the testing of such a psychological treat- development such as “ smart ” medical systems, medical ment tool. informatics, telemedicine, imaging, monitoring, artifi cial A 2.5-yr Mars expedition would lead to a far greater blood, and the miniaturization of laparoscopic equip- level of isolation and psychological stress than any space ment. Virtual reality refresher training for surgical proce- mission attempted previously. Because of this, a risk of dures is also not far away. Of most importance, the surgi- psychiatric decompensation would remain despite the cal capability of any medical care system ultimately will most careful genetic and personality screening. If a seri- be limited by the surgical capability and training of the ous psychiatric disorder were to develop during the crew medical offi cer. When and if a surgical procedure is mission, there would be no realistic opportunity for performed, then the same variable will occur as in con- evacuation. As a consequence, there would need to be ventional surgery concerning the innate surgical skills of an ample range of medications to treat psychiatric disor- the operator. An operator with poor surgical skills on the ders. Such medications would need to be effective in ground will have poor surgical skills in space. emergency and chronic psychiatric conditions, includ- ing severe mood, anxiety, and psychotic disorders. The choice of psychiatric medications for such a mission will Behavioral Health require a great deal of forethought and the mission CMO Providing adequate behavioral health services to as- would require signifi cant education in their use. tronauts on a long-duration lunar or Mars mission will require NASA psychiatrists and psychologists with ex- tensive experience working with astronauts and their Safe Passage families during the missions. Such personnel will re- This paper has summarized this panel’s views on the quire an in-depth knowledge and familiarity with the Vision’s principal challenges to space medicine. The fol- expedition crew and their family members, as well as a lowing compilation of critical technologies and capabil- true working knowledge of all aspects of the mission ities were identifi ed by a NASA life sciences technology pertaining to the spacefl ight environment, habitability, working group and the Institute of Medicine and listed sleep/wake schedules, workload, medical support ca- in the book, “ Safe Passage: Care for Explora- pabilities, and risks. tion Missions ” (Ball HR, Evans CH, eds. Washington, Regular private communication with crewmembers DC: National Academies Press, 2001). The approaches to will be required throughout the mission. During the ini- meeting them lies in the will and funding of the U.S. tial and very late stages of a Mars mission, private psy- Congress and other governments and the implementa- chological conferences (PPC) can be held using audio and tion by NASA and its international partners. Specifi cally visual communication in real time. However, most of the the critical life science technologies and capabilities mission will occur at such a distance that the communica- needed in the areas of medical screening risk mitigation, tion delay would make this impossible. PPC’s will then life support and habitability design, and microgravity need to occur via e-mail or perhaps through recorded countermeasures and health care are listed below. video response to a written query or a standard interview questionnaire. Such a barrier will render the interpersonal 1) Space Radiation Modeling human interaction and give-and-take of any needed • A space simulation/visualization system for assessing counseling or psychotherapy useless and will make psy- developing radiation conditions chological assessment and potential treatment far more • Model(s) to describe the dynamic behavior of the trapped radia- diffi cult. A long-duration lunar expedition would be an tion belts • Model(s) of the geomagnetic cutoff, including diurnal, seasonal, excellent test-bed for the monitoring and communication and activity dependence challenges of a Mars expedition mission. • Technologies for quantitative assessment of radiation risks

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• Model(s) of the interaction of the heavy ions in galactic cosmic 7) Calcium Deposition (Stones) rays with spacecraft, planetary atmospheres, and regoliths • Improved radiation transport and shielding codes • Systems that measure the changes in calcium during spacefl ight and • Evaluation of new materials, composites, and planetary regoliths how it affects the neurosensory, cardiac, muscle, or other systems as shielding media • Countermeasures (procedures and pharmacologic/nutritional agents) that prevent ectopic calcium deposition in 99% of the population 2) Radiobiology • Models, sensors, and systems to measure and predict the effects 8) Orthostatic Tolerance of radiation upon humans • Determination of RBE (radiobiological equivalents) for neoplastic • Hardware for an integrated countermeasures program to main- transformation of human cells tain orthostatic tolerance for landing, planetary excursion, emer- • Determination of RBE for lung and mammary cancers gency, entry, egress, and postfl ight rehabilitation • Radiophysical models for neoplastic transformation • Technologies for exercise, pharmacologic agents (e.g., mineral • Method(s) of calculating probabilities of cancer induction at the corticosteroid, fl uid augmentation), fl uid therapy, neurostimula- organ level tion, compression garment • Methods for determining the human genetic effects of High LET (linear energy transfer) radiation 9) Artifi cial Gravity Countermeasures • Models of performance and quality of life impairment • Strategies for determining and evaluating potential microgravity- • Hardware to assess artifi cial gravity as a countermeasure radiation synergism • Systems to determine the most effi cient combination of g-level • Operational measures (e.g., mission planning and operations, and exposure duration for intermittent centrifuge operation safe shelters, etc.) • Systems to determine the most effective combination of radius • Chemical and biological modifi ers and radioprotectants and rotation rates for continuous centrifuge operation • Systems to verify centrifuge effectiveness in maintaining skeletal integrity, calcium metabolism, physical performance, orthostatic 3) Space Radiation Monitoring tolerance, neurosensory function, and other physiological func- • Space-based (spectrometer/dosimeter) which tions, identifying positive and negative side effects can measure neutron energies to at least 20 MeV in the presence • Systems to verify the effect of intermittent and continuous centri- of high levels of protons fuge exposure on humans at several gravity values, including • Early warning system for predicting Solar Particle Events (SPE) near 0-g, 1/6-g (lunar surface), 3/8-g (Mars), and 1 g and their size, based on the X-ray and gamma-ray spectral char- acteristics of observed solar fl ares 10) Neurosensory and Sensorimotor Function • Small, portable electronic dosimeter, which can be used in EVA suits and habitable volumes (provides dose and dose-equivalent • Ultra-lightweight binocular 3-D video eye movement monitoring rates and integrated values) • Ultra-lightweight 6-degree-of-freedom head movement monitoring • New and advanced/improved techniques and materials for pas- • Nonhead coupled visual display system sive dosimetry, including biological radiation sensors • Wide fi eld stereo head mounted display (HMD) with eye and head movement monitoring and see through capability • Dynamic visual acuity testing and analysis system; 3-D video eye 4) Skeletal Integrity movement capture and analysis software • I n fl ight, compact, light weight dual energy X-ray absorption to • Mathematical models of visual-vestibular integration and adaptation perform hip, spine, and heel bone mineral density (BMD) • Head-body tracking system measurements • Mathematical models of postural and locomotor control • Automated urine collection, measurement, and sample storage/ • Dynamic posturography system analysis equipment • Ways to evaluate the role of proprioceptive and somatosensory • Load cells in pedals for cycle ergometer and angle measurement information in sensorimotor functions for hub and pedals • Human-rated angular and linear whole-body acceleration devices • Dynamometers for hip, knee, and ankle measurements in space • Techniques for measuring orientation and perceptual disturbances • Finite element analysis methods and equipment for skeleton • Tests/devices for evaluating ability to perform mental rotation on measurements/analysis with minimal radiation (model incorpo- Earth and in space rates bone morphology and bone density) • Tests/devices for evaluating adaptive changes in spatial orienta- tion during spacefl ight • Improved prefl ight and in-fl ight adaptation to altered vestibular, 5) Physical Performance Maintenance proprioceptive and somato sensory inputs • Means to monitor the effectiveness of nutrition and pharmaco- • Means to evaluate changes in sensory-motor performance logical agents, exercise and electro-myostimulation • Sensory substitution using electrical and/or magnetic stimulation • Means to assess lean body mass, aerobic/anaerobic capacity, muscle endurance/strength, thermal regulation, neuromuscular (coordina- 11) Countermeasures for Neurosensory and tion control), and compliance in applying countermeasures Sensorimotor Disturbances 6) Environmental Physiology/Biophysics • Means for prefl ight adaptation to altered sensory inputs to reduce sensorimotor disturbances, spatial orientation and perceptual • Sensors and systems to determine the effects of pressure and disturbances, and space motion sickness changes in pressure, especially in decompression illness (DCI) • Means for infl ight maintenance of Earth gravity sensorimotor • Systems to determine the effects of temperature on the health and and perceptual function (adaptation), including a short-arm cen- performance of the crew in spacecraft and during EVA trifuge, 3-d eye-head movement monitoring system with visual • Systems to measure metabolic rates, especially during EVA, and display system, and foot pressure (somatosensory) input device to relate them to fatigue and risk of DCI • Vibrotactile orientation system/device for infl ight maintenance • Systems to measure the effects of different gas species such as ox- of spatial orientation - specifi cally during EVA ygen, water, carbon dioxide, and ionized particles • Methods of treating of DCI, such as hyperbaric therapy for DCI and hyperbaric/oxygen therapy 12) Diagnostic/Physiological Monitoring & Telemedicine • Tools for understanding how spacecraft bioelectromagnetic fi elds • Laboratory diagnostics (clinical chemistry, hematology, pathol- and nonionizing radiation affects the crew ogy, microbiology, etc.); imaging diagnostics (radiographic, mag- • In-fl ight/in-suit Doppler systems netic resonance, ultrasound, etc.) • Methods for treating decompression illness • Advanced monitoring and sensors

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• Non- or minimally-invasive monitors (ECG, BP, SpO 2, HR, T, etc.) • Technologies for 0-g/partial-g washing and drying of clothes • Implantable/injectable/ingestable biomedical sensors • Technologies for providing crew consumables such as food sup- • Telemetry to/from sensors and processing systems plies and so on, in a wide variety of emergency situations with • Autonomous/expert systems (monitoring, diagnosis, treatment, the least possible mass and surgical assistance) • Advanced technologies to repair systems without Earth support • Multimedia medical record technologies • Means for analyzing spares requirements, documenting repair • Advanced user interfaces for medical diagnosis, treatment and procedures at very low level (e.g., components rather than training (VR, haptic, etc.) boards), and developing multipurpose troubleshooting tools • Advanced computer-based medical training and simulation tech- • Improved cleaning technologies niques and systems • A method of tracking the location and status (e.g., health, func- • Robotic (autonomous) and teleoperated medical assistance systems tional state, etc.) of items (e.g., by embedding a small microchip with integral microtransmitter into every object) 13) Immune Protection • Means to determine maximal acceptable decrements of cellular 19) Food and Galley and humoral protective mechanisms, relation of the immune sys- • Shelf life extension to store a complete and acceptable diet for the tem dysfunction to the incidence of infection, cancer induction, 3 to 5 yr required by Mars mission scenarios allergy, and autoimmune disease manifestations • Advanced food packaging • Pharmacological agent(s) as a countermeasure • Means for food preparation for crew • Means to decrease “stress response;” means to improve the cur- • Reduction in waste generated (both food and packaging wastes) rent Prefl ight Health Stabilization Program • Enhancements in acceptability, palatability, and variety • In-fl ight cytometer, delayed type hypersentitivity test device ( “ skin test ” ), in-fl ight Enzyme-Linked Immunoassay (ELISA) 20) Food Development from Chamber Grown Plants system, in-fl ight blood collection and distribution system, and a cell culture and challenge system • Harvesting technologies • Processing (e.g., drying, grinding, making bread from wheat fl our) 14) Medical Intervention • Sugar and oil production compatible with manned chambers • Systems for emergency surgery and critical care • Systems for rescue, resuscitation, stabilization, and transport 21) Habitability • Fluid therapy systems, with infusion pumps, on-site production • Measurement techniques to determine personal space, time, and of sterile fl uids, nutritional support, blood and blood component privacy requirements replacement • Measurement tools to determine actual and preferred levels of • Extended (3 yr) shelf-life pharmaceuticals habitability factors such as volume and area, noise, vibration, • Medical waste management system odor, temperature, and humidity, and their relationship to crew • Advanced medical storage systems (samples, pharmaceuticals, etc.) performance and productivity in long-duration missions • Microsurgery/microtherapeutics equipment and protocols • Tools to measure personal preference for habitability factors in • Planetary surface and microgravity hyperbarics individual crewmembers • Portable (infl atable) hyperbaric chamber 22) Contingencies 15) Psychosocial Stability • Model that can continuously estimate the likelihood of potential • An integrated countermeasures program for Psychosocial critical events Stability with prefl ight training, group support, self help, phar- • Analytical model that identifi es and evaluates potential responses macologic treatment, exercise, etc. to critical events for a Decision Support System • Systems designed to measure, evaluate, and preserve psychoso- • Advanced and/or improved models of human decision making cial stability that provide assistance in predicting and resolving contingencies or critical events in human/human or human/system situations 16) Crew Productivity • Technology tools and models for determining acceptable perfor- CONCLUSIONS mance ranges for different types of tasks Planetary missions are going to be inherently risky. It • Tools for modeling complex missions with multiple participants, assessing predicted vs. actual productivity, and updating the is the task of the medical profession to estimate and ex- model status to identify potential problems or failures plain the medical risks clearly, so that NASA and all those involved can weigh them against the overall risks 17) Maintenance of Profi ciency and benefi ts of the mission and decide whether to ac- • Tools for design-time information collection/capture in develop- cept them. Thus there is no defi nite threshold short of ing training materials which we are not ready, and beyond which we are • Authoring tools optimized for computerized training for unique ready, to go to Mars. We will always be ready, if the or unusual skills or tasks • Nonintrusive technologies for monitoring individual and group risks are deemed worth taking; and we will never stop performance over time learning how to reduce them. Perhaps the biggest chal- • Advanced virtual reality systems with low power, volume, and lenge will be execution – implementing what we know mass requirements, which provide position tracking, wide fi eld- of-view head mounted displays, and haptic feedback for on- with excellence – in medical crew selection and train- board refresher training and skill monitoring ing, in countermeasures, in remote medical care. This • Authoring languages for VR training systems that incorporate er- must be done in stepwise approach, utilizing the ISS ror feedback to the user, prompting, and tools for data collection and then the Moon, toward our foreseeable goal, the and performance assessment journey to Mars.

18) Crew Accommodations ACKNOWLEDGMENTS • New methods of trash disposal which reclaim useful materials The opinions stated herein are those of the author(s) and may not while minimizing or eliminating disposal volume, such as plastic refl ect the views and positions of the National Aeronautics and Space recycling Administration.

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