1

Introduction

Every age has its dreams, its symbols of romance. Past generations were moved by the graceful power of the great windjammers, by the distant whistle of locomotives pounding through the night, by the caravans leaving on the Golden Road to Samarkand, by quinqueremes of Nineveh from distant Ophir.…Our grandchildren will likewise have their inspiration—among the equatorial stars. They will be able to look up at the night sky and watch the stately procession of the Ports of Earth—the strange new harbors where the ships of space make their planetfalls and their departures.

Sir Arthur C. Clarke, The Promise of Space, 1968, p. 125

From the dawn of oral and recorded history, as enshrined in the words of Homer and Herodotus, humans have pursued the unknown. Exploration undertaken in the name of adventure and scientific innovations, new trade markets, geopolitical dominance, and the advancement of human civilization has led to the discovery of distant lands and new ideas that challenge accepted beliefs and perceived limitations. Naval and land exploration have connected remote cultures and civilizations, generated new sources of wealth, expanded scientific and technological knowledge and capabilities, and promoted an exchange of ideas that has revolutionized long-held beliefs about the world.

The last half of the 20th century welcomed an era of great potential for discovery. In 1961, Soviet cosmonaut Yuri Gagarin became the first



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1 Introduction Every age has its dreams, its symbols of romance. Past gen- erations were moved by the graceful power of the great windjammers, by the distant whistle of locomotives pounding through the night, by the caravans leaving on the Golden Road to Samarkand, by quinqueremes of Nineveh from dis- tant Ophir.…Our grandchildren will likewise have their in- spiration—among the equatorial stars. They will be able to look up at the night sky and watch the stately procession of the Ports of Earth—the strange new harbors where the ships of space make their planetfalls and their departures. —Sir Arthur C. Clarke, The Promise of Space, 1968, p. 125 From the dawn of oral and recorded history, as enshrined in the words of Homer and Herodotus, humans have pursued the unknown. Ex- ploration undertaken in the name of adventure and scientific innovations, new trade markets, geopolitical dominance, and the advancement of hu- man civilization has led to the discovery of distant lands and new ideas that challenge accepted beliefs and perceived limitations. Naval and land exploration have connected remote cultures and civilizations, generated new sources of wealth, expanded scientific and technological knowledge and capabilities, and promoted an exchange of ideas that has revolution- ized long-held beliefs about the world. The last half of the 20th century welcomed an era of great potential for discovery. In 1961, Soviet cosmonaut Yuri Gagarin became the first 13

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14 LONG DURATION AND EXPLORATION SPACEFLIGHT human in space (NASA, 2014c), once again expanding humanity’s per- ception of the possible. Later that year, U.S. astronaut Alan Shepard be- came the first American to fly into space and, in 1962, John Glenn made history as the first U.S. astronaut to orbit Earth (Garber and Launius, 2005). Since those monumental firsts, astronauts have walked on the Moon; launched, retrieved, and repaired various satellites (e.g., the Hub- ble Space Telescope); conducted thousands of scientific and engineering research experiments; and assembled and resupplied the International Space Station (ISS) (NRC, 2011). Investment in space exploration has led to cutting-edge aerospace technology, weather satellites and climate modeling, communication and navigation satellites, new and transforma- tional medical technologies, and a greater understanding of the effects of space on human physiology (Dick and Cowing, 2004). However, these achievements have come at great cost. Exploration, especially in relatively new environments, involves some known risks and a wider range of unknown risk, which jeopardize the safety of explorers and their teams as well as the mission. For exam- ple, during the Age of Discovery (15th to 17th centuries), unprecedented naval explorations often required extended voyages during which crews experienced hardship, deprivation, and disease (Harrison, 2013). The dynamic and unpredictable conditions of extreme environments, often complicated by a lack of available resources and equipment failures, have taken countless lives over many centuries (e.g., Solomon, 2001; Davis, 2011). In the context of space exploration, more than 20 U.S. astronauts have died during, and in preparation for, spaceflight (NASA, 2014a). But past failures, as well as successes, provide opportu- nities to critically examine, anticipate, and mitigate similar risks to future explorers. As modern explorers continue to push the limits of human endurance in even more remote and inhospitable environments, risks to individuals and other interested parties will also change, raising new questions about risk tolerance limits and thresholds of acceptable risk for both individuals and society. Responsible decision making will call for a careful articula- tion of the values that shape the balance our society strikes between the quest for discovery and avoidance of harm.

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INTRODUCTION 15 SCOPE OF WORK The United States formally launched efforts to engage in “aeronauti- cal and space activities” in 1958, when Congress passed the National Aeronautics and Space Act, establishing the civilian-controlled NASA.1 NASA’s charge expanded the scope of federally supported aeronautical research,2 to include “the problems of flight within and outside the Earth’s atmosphere,” excepting activities related to weapon systems, na- tional security, and military activities.3 Specifically, Congress directed NASA to engage in activities “devoted to peaceful purposes for the bene- fit of all mankind” with specific objectives, including (1) The expansion of human knowledge of phenomena in the at- mosphere and space; (2) The improvement of the usefulness, performance, speed, safe- ty, and efficiency of aeronautical and space vehicles; (3) The development and operation of vehicles capable of carrying instruments, equipment, supplies, and living organisms through space; (4) The establishment of long-range studies of the potential bene- fits to be gained from, the opportunities for, and the problems involved in the utilization of aeronautical and space activities for peaceful and scientific purposes; (5) The preservation of the role of the United States as a leader in aeronautical and space science and technology and in the ap- plication thereof to the conduct of peaceful activities within and outside the atmosphere; (6) The making available to agencies directly concerned with the national defense of discoveries that have military value or sig- nificance, and the furnishing by such agencies, to the civilian agency established to direct and control nonmilitary aeronauti- cal and space activities, of information as to discoveries which have value or significance to that agency; 1 The National Aeronautics and Space Act of 1958, P.L. 85-568 (July 29, 1958). 2 The National Advisory Committee on Aeronautics, NASA’s predecessor, was found- ed to “supervise and direct the scientific study of the problems of flight, with a view to their practical solution, and to determine the problems which should be experimentally attacked, and to discuss their solution and their application to practical questions” (The Naval Appropriations Act of 1916, P.L. 63-271, [March 3, 1915]). 3 The National Aeronautics and Space Act of 1958, P.L. 85-568 (July 29, 1958).

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16 LONG DURATION AND EXPLORATION SPACEFLIGHT (7) Cooperation by the United States with other nations and groups of nations in work done pursuant to this Act and in the peaceful application of the results, thereof; and (8) The most effective utilization of the scientific and engineering resources of the United States, with close cooperation among all interested agencies of the United States in order to avoid unnecessary duplication of effort, facilities, and equipment.4 These objectives have played an integral role in shaping NASA’s history and vision, and are important considerations when exploring the ethics defining health standards in human spaceflight.5 NASA is charged with designing and implementing space missions, which pose high risks to human health and safety, and with risk assessment and management. This broad governance structure provides opportunities to design feed- back loops that can translate data and experience into improved risk management strategies, but it can also lead to perceived and actual con- flicts of interest that have important ethical implications, as discussed later in this report. Moreover, important shifts in human space exploration continue to redefine the sphere in which space travel occurs. NASA’s human space- flight program has grown from a one-man launch to an ongoing space presence aboard the ISS, involving men and women from more than a dozen nations (NASA, 2013c). The Moon, once a short-term destination, is now considered by some as a possible permanent base for human ac- tivity (Duke et al., 1985; Angelo, 2009; Duke, 2013; NASA, 2014b). The U.S. government has articulated visions that include a foreseeable human presence on the Moon (once again) and on Mars’ surface.6,7 Long dura- tion and exploration spaceflights involving humans appear to be on the immediate horizon (NASA, 2004; Bolden, 2013; Norwood and Tahu, 4 Congress has since expanded NASA’s objectives to include additional responsibili- ties, such as the “preservation of the United States preeminent position in aeronautics and space through research and technology development related to associated manufacturing processes” (National and Commercial Space Programs, P.L. 111-314 [December 18, 2010]). 5 This report does not review the history of NASA or the U.S. space program, but nu- merous texts are available (e.g., Garber and Launius, 2005; Dick, 2008, 2010; Logsdon and Launius, 2008). 6 National Aeronautics and Space Administration Authorization Act of 2005, P.L. 109- 155 (December 30, 2005). 7 National Aeronautics and Space Administration Authorization Act of 2008, P.L. 110- 422 (October 15, 2008).

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INTRODUCTION 17 2013), and discussions about sending humans to an asteroid and Mars have stimulated debate about the fiscal and ethical limits of spaceflight. Contemporary space exploration is also an increasingly cooperative effort. Commercial and international collaborations propel efforts to in- stitute a sustained human presence deeper into the solar system. Multiple companies are developing their own space vehicles and business plans (NASA, 2013b). With the retirement of the Space Shuttle Program, NASA has had to rely on other governments and space agencies, and will, in the future, rely on the commercial sector to provide low Earth orbit (LEO)8 transportation for its astronauts to NASA-supported facilities in space (NASA, 2013d). Increased collaboration has also led to challenges associated with harmonizing regulations and policies, including those that govern health risks to astronauts. Within NASA, the Human Exploration and Operations Mission Di- rectorate provides “leadership and management of NASA space opera- tions related to human exploration in and beyond [LEO]” as well as “NASA space operations related to Launch Services, Space Transporta- tion, and Space Communications in support of both human and robotic exploration programs” (NASA, 2013a). Recognizing that the acceptance of increased levels of risk brings with it a profound responsibility to min- imize and mitigate risks to the greatest extent feasible (Bolden, 2013), NASA has implemented a comprehensive risk management policy, as described in Chapter 2, which informs the conception, development, and execution of NASA programs and projects (NASA, 2011a). This policy includes consideration of the risks and benefits of specific human space- flight missions. One of NASA’s primary risk management activities includes devel- oping and enforcing health standards to provide a “healthy and safe envi- ronment for crewmembers, and to provide health and medical programs for crewmembers during all phases of space flight” (NASA, 2007, p. 8). The health standards examined in this report are specified in Volumes 1 and 2 of the NASA Spaceflight Human System Standards (NASA, 2007, 2011b). The committee uses the shorter term “health standards” to refer to this set of standards throughout this report. NASA’s health standards include preflight, inflight, and postflight health issues and fall into three categories: fitness-for-duty standards, space-permissible exposure limits, and permissible outcome limits (NASA, 2007). 8 LEO is the orbit above Earth’s surface at altitudes between 100 miles (160 km) and approximately 1,240 miles (2,000 km) (National Geographic, 2014).

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18 LONG DURATION AND EXPLORATION SPACEFLIGHT The degree to which NASA astronauts and facilities can take part in collaborative space-exploration activities is governed, in part, by the health standards adopted to protect individual astronauts from the ad- verse health effects of spaceflight. Long duration and exploration space- flights will involve increased exposures of crews to known risks, as well as to a wide range of risks that are poorly characterized and, perhaps, unforeseeable. “Despite superficial similarities to other space missions and analogues, the extended durations and astronomical distances in- volved in lunar and [M]artian missions will make these activities far more difficult and dangerous” (Stuster, 1996, p. 3). As NASA and Congress continue to discuss the next generation of NASA’s missions and the U.S. role in international space efforts, it is important to understand the ethical factors that drive decision making surrounding health standards and mission design for NASA activities. Committee Charge Despite the known and unknown health risks, some individuals would undoubtedly agree to serve on exploration and long duration spaceflights. According to the Institute of Medicine (IOM) report Safe Passage: Astronaut Care for Exploration Missions, “the opportunity to travel in space is highly desired by those in the astronaut corps[, and] although long-duration space missions will involve substantial hazards, there are likely to be many who will gladly accept the risk in exchange for the unique opportunity to leave the bounds of Earth’s orbit” (IOM, 2001, p. 179). Given uncertainties about health and safety risks facing astronauts during extended stays on the ISS or on exploration missions to an asteroid or Mars, NASA asked the IOM to examine the ethics and policy principles that should guide decision making about health stand- ards for long duration and exploration class missions “when existing health standards cannot be fully met” or adequate standards cannot be developed based on existing evidence (see Box 1-1). Based on this lan- guage from its task, the committee decided to use the phrase “fails to meet” or variants of this phrase to indicate when conditions or uncertain- ties related to spaceflights either may or will subject astronauts to higher levels of risk than those allowed by existing health standards. To respond to the statement of task (see Box 1-1), the IOM convened a 15-member Committee on Ethics Principles and Guidelines for Health Standards for Long Duration and Exploration Spaceflights (“the commit- tee”), which included experts in ethics, spaceflight and aerospace medi-

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INTRODUCTION 19 cine, occupational health, risk assessment, law, behavioral health, and health standards. In essence, the committee’s statement of task asks which ethics principles need to be considered in questions about accepta- ble risks to humans under highly uncertain conditions, and how these principles should be applied to decisions about long duration or explora- tion spaceflights sponsored by the federal government. BOX 1-1 Statement of Task The National Aeronautics and Space Administration (NASA) is in the process of planning for exploration class missions of long duration and be- yond low Earth orbit (LEO). An ad hoc committee of the Institute of Medi- cine (IOM) will conduct a study to examine policy and ethical issues relevant to crew health standards for these missions. The committee would consider the application of existing health standards and the poten- tial development of a new set of standards for missions beyond LEO. These standards would address potential hazardous exposures and work- ing conditions that are uncertain, unknown, or that go beyond current NASA risk limits. NASA is looking in particular for a framework of ethical and policy principles that can help guide decision making associated with implementing health standards for exploration class space missions when existing standards cannot be fully met, or the level of knowledge of a given condition is sufficiently limited that an adequate standard cannot be devel- oped, for the mission. As part of its deliberations, the committee will consider and respond to options proposed by NASA, as well as offer options of its own. Given the long-term importance of this task for NASA, the committee’s report will fully detail supporting rationale for all recommendations. Questions to be considered include 1. What factors should be considered in the implementation of current health standards (which are defined in Volumes 1 and 2 of NASA Space Flight Human System Standards) in exploration class missions and the development of exploration class health standards if neces- sary? a. What ethical considerations are involved in developing and imple- menting health and safety standards for manned space exploration when the exposures and risks are uncertain, unknown, and/or when exposures and risks might exceed current standards? b. What standards of informed consent regarding the health risks of the mission are appropriate, and what are the ethical limits of in- formed consent processes in these circumstances? What princi- ples should be applied (when relevant) to communicating the uncertainty regarding health risks?

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20 LONG DURATION AND EXPLORATION SPACEFLIGHT c. What are appropriate modifiers for standards for protecting indi- viduals when there is an incomplete understanding and knowledge of the potential risks or hazardous exposures, or when exposures and risks may exceed current standards? d. Should all astronauts and spaceflight crew members be protected to the same risk level or should potential individual differences be considered? Would one standard be sufficient for the entire spaceflight crew or do known or unknown differences in risk need to be addressed to provide a uniform level of protection? 2. Are there models or examples of other situations with unknown health risks (or risks that could exceed current standards) that could inform NASA policy and, if so, how? Clear definitions of several key terms are essential to understand the scope of the committee’s task. NASA has defined “exploration” missions as “any activity outside of the radiation protection of the near-Earth magnetic field (i.e., Moon, asteroid, Mars)” and “long duration missions” as those extending beyond 30 days.9 However, to be consistent with its statement of task, the committee generally refers to exploration class missions as those beyond LEO. Missions to areas beyond LEO will in- volve radiation exposures above those consistently encountered on the ISS. In the context of the committee’s charge, these areas are conceptual- ly important because they not only help define the directive of a mission (i.e., to reach a particular destination in space), but they also define the parameters of risk exposure and the resulting impact of current health standards on a specific mission. This report focuses on the benefits of human spaceflight only to the extent that it is relevant to the identification of ethics principles and the development of a decision framework related to health standards for long duration and exploration spaceflights (see Chapters 5 and 6). The com- mittee was not tasked with drawing conclusions or making recommenda- tions about the value or advisability of future human spaceflight, the prioritization of NASA activities, or the appropriate level of funding NASA should receive to support human spaceflight activities. Moreover, this report does not examine the complexities of quantitative risk assess- ment and risk-benefit analyses, processes that should influence NASA’s decisions about long duration and exploration spaceflight. Instead, the 9 Personal communication, Richard Williams, NASA, November 19, 2013.

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INTRODUCTION 21 scope of this report is limited to identifying an ethics framework upon which other data and analyses should be evaluated. In addition to reviewing NASA documents and relevant literature, the committee held two public workshops (see Appendix A for the work- shop agendas), one public teleconference, and six closed-session meet- ings over the course of 10 months to inform its deliberations. At the public workshops and open sessions, the committee solicited input about the challenges, goals, and consequences associated with health standards for long duration and exploration class missions. The committee heard from NASA experts involved in risk assessment and management for the agency, as well as a number of past and current astronauts. Throughout this study, NASA leadership and staff provided substantial cooperation, support, and responsiveness as the committee sought additional infor- mation for its deliberations. The committee also solicited input from ex- perts on the ethics of risk acceptance, decision making in the context of high-risk occupations, and federal agency health standard implementa- tion and enforcement. Related Work of the National Academies The National Research Council (NRC) and the IOM have been in- volved in providing advice to NASA about space travel and human space exploration since the late 1950s (NRC, 2013a) and have produced nu- merous studies, such as Safe Passage: Astronaut Care for Exploration Missions (IOM, 2001); Review of NASA’s Longitudinal Study of Astro- naut Health (IOM, 2004); Review of NASA’s Human Research Program Evidence Books: A Letter Report (IOM, 2008); and Managing Space Ra- diation Risk in the New Era of Space Exploration (NRC, 2008). The IOM and the NRC have also addressed risk acceptability and decision making in many other contexts (NRC, 1996, 2009), including environ- mental settings (IOM, 2013). These reports have helped inform the ap- proach recommended in the present report. The NRC is currently conducting a study examining the “long-term goals, core capabilities, and direction of the U.S. human spaceflight pro- gram” to “provide findings, rationale, prioritized recommendations, and decision rules that could enable and guide future planning for [sustaina- ble] U.S. human spaceflight exploration” (NRC, 2013b). As part of the work to address its charge, the NRC committee will consider the ration- ales for human space exploration. The committee will also describe the

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22 LONG DURATION AND EXPLORATION SPACEFLIGHT value of NASA’s human spaceflight activities in the context of national goals (NRC, 2013b) and international partnerships. REPORT STRUCTURE This report is written for a broad audience that may not be familiar with the technical aspects of NASA’s health standards or the intricacies of ethics. Chapters 2 and 3 of the report detail NASA’s risk management process in the context of current health standards and provide a few ex- amples of relevant health risks. Chapter 4 examines various roles of NASA and NASA astronauts and provides examples of regulations or policies that apply to similar activities in terrestrial environments, ex- tracting common factors that appear to influence decisions about risk acceptance. Chapter 5 recommends specific ethics principles that are rel- evant to decisions about human spaceflight. Finally, the report concludes in Chapter 6 by proposing responsibilities applicable to implementing the ethics principles and a decision framework to guide determinations about possible limits and exceptions to health standards for long duration and exploration human spaceflights. REFERENCES Angelo, J.A. 2009. Encyclopedia of space and astronomy. New York: Infobase Publishing. Bolden, C. 2013. Presentation at the first meeting of the IOM Committee on Ethics Principles and Guidelines for Health Standards for Long Duration and Exploration Spaceflights. Washington, DC, May 30. Clarke, A. C. 1968. The promise of space. New York: Harper and Row. Davis, W. 2011. Into the silence: The Great War, Mallory, and the conquest of Everest. New York: Alfred A. Knopf. Dick, S. 2008. Remembering the space age. Washington, DC: NASA. http://www.nss.org/resources/library/spacepolicy/Remembering_the_Space_ Age.pdf (accessed January 27, 2014). Dick, S. 2010. NASA’s first 50 years: Historical perspectives. http://history.nasa. gov/SP-4704.pdf (accessed January 27, 2014). Dick, S., and K. Cowing. 2004. Risk and exploration: Earth, sea and the stars. Presentation at NASA Administrator’s Symposium. Monterey, CA, September 26-29. http://history.nasa.gov/SP-4701/riskandexploration.pdf (accessed January 27, 2014).

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INTRODUCTION 23 Duke, M. B. 2013. Lunar objectives, benefits, pathways, and strategy. Presentation at the National Research Council’s meeting of the Committee on Human Spaceflight. Washington, DC, October 21. http//sites.national academies.org/DEPS/ASEB/DEPS_069080 (accessed March 17, 2014). Duke, M. B., W.W. Mendell, and B.B. Roberts. 1985. Strategies for a permanent lunar base. In: Lunar bases and space activities of the 21st century, edited by W.W. Mendell. Houston, TX: Lunar and Planetary Institute. Pp. 57-68. Garber, S., and R. Launius. 2005. A brief history of NASA. http://history.nasa.gov/ factsheet.htm (accessed December 4, 2013). Harrison, M. 2013. Scurvy on sea and land: Political economy and natural history, c. 1780–c. 1850. Journal for Maritime Research 15(1):7-25. IOM (Institute of Medicine). 2001. Safe passage: Astronaut care for exploration missions. Washington, DC: National Academy Press. IOM. 2004. Review of NASA’s longitudinal study of astronaut health. Washington, DC: The National Academies Press. IOM. 2008. Review of NASA’s Human Research Program evidence books: A letter report. Washington, DC: The National Academies Press. IOM. 2013. Environmental decisions in the face of uncertainty. Washington, DC: The National Academies Press. Logsdon, J. M., and R. D. Launius. 2008. Exploring the unknown: Selected doc- uments in the history of the US civil space program, Volume VII. NASA SP- 2008-4407. Washington, DC: NASA. NASA (National Aeronautics and Space Administration). 2004. President Bush announces new vision for space exploration program. http://history.nasa.gov/ Bush%20SEP.htm (accessed December 31, 2013). NASA. 2007. NASA space flight human system standard. Volume 1: Crew health. NASA-STD-3001. https://standards.nasa.gov/documents/detail/ 3315622 (accessed January 27, 2014). NASA. 2011a. NASA risk management handbook. http://www.hq.nasa. gov/office/codeq/doctree/NHBK_2011_3422.pdf (accessed January 27, 2014). NASA. 2011b. NASA space flight human system standard. Volume. 2: Human factors, habitability, and environmental health. NASA-STD-3001. https://standards.nasa.gov/documents/detail/3315785 (accessed December 4, 2013). NASA. 2013a. Human exploration and operations at NASA. http://www.nasa. gov/directorates/heo/home/index.html#.UsHZEPRDsQE (accessed December 30, 2013). NASA. 2013b. Commercial space transportation. http://www.nasa.gov/ exploration/commercial (accessed December 30, 2013). NASA. 2013c. International Space Station—space station assembly—international partners and participants. http://www.nasa.gov/mission_pages/station/ structure/elements/partners.html (accessed March 11, 2014).

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24 LONG DURATION AND EXPLORATION SPACEFLIGHT NASA. 2013d. NASA’s management of the commercial crew program. http://oig.nasa.gov/audits/reports/FY14/IG-14-001.pdf (accessed December 30, 2013). NASA. 2014a. Kennedy Space Center visitor complex: Astronaut memorial. http:// www.kennedyspacecenter.com/the-experience/astronaut-memorial.aspx (acc- essed January 13, 2014). NASA. 2014b. New data about the Moon may help create lunar bases. http://sservi.nasa.gov/articles/lunar-bases (accessed March 12, 2014). NASA. 2014c. Yuri Gagarin: First man in space. http://www.nasa.gov/mission_ pages/shuttle/sts1/gagarin_anniversary.html (accessed March 12, 2014). National Geographic. 2014. Education: Atmosphere. http://education. nationalgeographic.com/education/encyclopedia/atmosphere/?ar_a=1 (access- ed February 7, 2014). Norwood, T., and G. Tahu. 2013. Proposed Mars 2020 mission: NEPA scoping meetings. Presentation at the National Enviromental Policy Act of 1969 scoping meetings. Washington, DC, September 11. NRC (National Research Council). 1996. Understanding risk: Informed deci- sions in a democratic society. Washington, DC: National Academy Press. NRC. 2008. Science and decisions: Advancing risk assessment. Washington, DC: The National Academies Press. NRC. 2011. Preparing for the high frontier: The role and training of NASA astronauts in the post-space shuttle era. Washington, DC: The National Academies Press. NRC. 2013a. About the Space Studies Board. http://sites.nationalacademies. org/SSB/ssb_052196 (accessed January 14, 2014). NRC. 2013b. Committee on Human Spaceflight statement of task. http:// sites.nationalacademies.org/DEPS/ASEB/DEPS_069080#Statement_of_Task (accessed January 14, 2014). Solomon, S. 2001. The coldest march: Scott’s fatal Antarctic expedition. New Haven, CT: Yale University Press. Stuster, J. 1996. Bold endeavors: Lessons from polar and space exploration. Annapolis, MD: Naval Institute Press.