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Scientific Prerequisites for the Human Exploration of Space

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^ ~ ~ `. bcle-< ]c Visited for the Human Explorudon of Space CommUtcc on Human [~plor~ion Space Studios Board Commission on Pbysica1 Scicncos, Hathomadcs, and Applicabons Nabona1 Rcscarcb CouncH NATIONAL ACADEMY PRESS Washington, Day. 1993

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NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance. This report has been reviewed by a group other than the authors according to procedures approved by a Report Review Committee consisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the further- ance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Frank Press is president of the National Academy of Sciences. The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Robert M. White is president of the National Academy of Engineering. The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Kenneth I. Shine is president of the Institute of Medicine. The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy's pur- poses of furthering knowledge and advising the federal government. Functioning in accor- dance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engi- neering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Frank Press and Dr. Robert M. White are chairman and vice chairman, respectively, of the National Research Council. Support for this project was provided by Contract NASW 4627 between the National Academy of Sciences and the National Aeronautics and Space Administration. Cover: Mars mosaic image courtesy of Alfred McEwen of the U.S. Geological Survey, Flagstaff, Arizona. Lunar crescent image courtesy of Dennis di Cicco. Cover design by Penny Margolskee. Copies of this report are available from Space Studies Board National Research Council 2101 Constitution Avenue, N.W. Washington, D.C. 20418 Printed in the United States of America

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COMMITTEE ON HUMAN EXPLORATION NOEL W. HINNERS, Martin Marietta Civil Space and Communications Company, Chair RICHARD L. GARWIN, IBM T.J. Watson Research Center LOUIS J. LANZEROTTI, AT&T Bell Laboratories ELLIOTT C. LEVINTHAL, Stanford University WILLIAM J. MERRELL, JR., Texas A&M University ROBERT H. MOSER, University of New Mexico GEORGE DRIVER NELSON, University of Washington SALLY K. RIDE,* California Space Institute Staff DAVID H. SMITH, Executive Secretary BOYCE N. AGNEW, Administrative Assistant *Former committee member who participated in writing this report. iii

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SPACE STUDIES BOARD LOUIS J. LANZEROTTI, AT&T Bell Laboratories, Chair JOSEPH A. BURNS, Cornell University ANDREA K. DUPREE,* Harvard-Smithsonian Center for Astrophysics JOHN A. DUTTON, Pennsylvania State University LARRY ESPOSITO,* University of Colorado JAMES P. FERRIS, Rensselaer Polytechnic Institute HERBERT FRIEDMAN, Naval Research Laboratory RICHARD L. GARWIN,* IBM T.J. Watson Research Center RICCARDO GIACCONI, European Southern Observatory NOEL W. HINNERS, Martin Marietta Civil Space and Communications Company JAMES R. HOUCK,* Cornell University DAVID A. LANDGREBE, Purdue University ROBERT A. LAUDISE, AT&T Bell Laboratories RICHARD S. LINDZEN, Massachusetts Institute of Technology JOHN H. McELROY, University of Texas, Arlington WILLIAM J. MERRELL, JR., Texas A&M University RICHARD K. MOORE,* University of Kansas ROBERT H. MOSER, University of New Mexico NORMAN F. NESS, University of Delaware MARCIA NEUGEBAUER, Jet Propulsion Laboratory MARK SETTLE, ARCO Oil Company WILLIAM A. SIRIGNANO, University of California, Irvine FRED W. TUREK, Northwestern University ARTHUR B.C. WALKER, Stanford University MARC S. ALLEN, Director *Term ended during 1992. in

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COMMISSION ON PHYSICAL SCIENCES, MATHEMATICS, AND APPLICATIONS RICHARD N. ZARE, Stanford University, Chair JOHN A. ARMSTRONG, IBM Corporation PETER J. BICKEL, University of California, Berkeley GEORGE F. CARRIER, Harvard University GEORGE W. CLARK, Massachusetts Institute of Technology MARYE ANNE FOX, University of Texas, Austin AVNER FRIEDMAN, University of Minnesota SUSAN L. GRAHAM, University of California, Berkeley NEAL F. LANE, Rice University ROBERT W. LUCKY, Bell Communications Research CLAIRE E. MAX, Lawrence Livermore National Laboratory CHRISTOPHER F. McKEE, University of California, Berkeley JAMES W. MITCHELL, AT&T Bell Laboratories RICHARD S. NICHOLSON, American Association for the Advancement of Science ALAN SCHRIESHEIM, Argonne National Laboratory A. RICHARD SEEBASS III, University of Colorado KENNETH G. WILSON, Ohio State University NORMAN METZGER, Executive Director v

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Preface For the past 20 years, the future directions of the U.S. program of human spaceflight have been a matter of discussion, debate, and contro- versy within and among the government, industry, the scientific commu- nity, and the public. Many advocates of human space exploration now agree that the next steps in piloted flight after Space Station Freedom in- volve returning to the Moon and, eventually, voyaging to Mars. The space science community, however, is agreed that there is no a priori scientific requirement for human exploration of the Moon and Mars. This view is reflected in Toward a New Era in Space: Realigning Policies to New Reali- ties (National Academy Press, Washington, D.C., 1988), a report prepared by the National Academy of Sciences and the National Academy of Engi- neering, which stated that "the ultimate decision to undertake further voy- ages of human exploration and to begin the process of expanding human activities into the solar system must be based on nontechnical factors." In that light it is proper to ask, then, what is a proper role for the scientific community in any program of human exploration? Well before a human exploration program is implemented, the U.S. scientific community must involve itself by providing the scientific advice and participation necessary for enabling human exploration. Then, because virtually all mission concepts for human exploration incorporate scientific research as a major goal, it is incumbent on the research community to study how it should respond to the opportunities enabled by the existence of human exploration. The time to do that is now, for it is during the vii

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vit! PREFACE conceptualization and initial development of exploration programs that the research community has its greatest opportunity to shape the relevant politi- cal, technical, and scientific decisions. Such participation is responsive to the finding enunciated in the Report of the Advisory Committee on the Future of the U.S. Space Program (U.S. Government Printing Office, Washington, D.C., 1990), that science is "the fulcrum of the entire space effort." Since its establishment in 1958, the Space Studies Board (SSB; for- merly the Space Science Board) has been the principal nongovernmental advisory body on civil space research in the United States. In this capacity, the board established the Committee on Human Exploration (CHEX) to examine many of the science and science-policy matters concerned with the return of astronauts to the Moon and eventual voyages to Mars. The Board asked CHEX to consider three major questions: 1. What scientific knowledge must be obtained as a prerequisite for prolonged human space missions? 2. What scientific opportunities might derive from prolonged human space missions? 3. What basic principles should guide the management of both the prerequisite science activities necessary to enable human exploration and the scientific activities that may be carried out in conjunction with human exploration? This report focuses on the first of these topics. Reports concerning the second and third topics are in their final stages of preparation and will be available in the near future. The Space Studies Board and CHEX concluded that the existing re- search strategies of several of its discipline committees form a solid basis for determining the scientific research necessary to enable future voyages by humans to the Moon and Mars. To establish a context for its study, however, CHEX first examined the scientific aspects of various Moon/Mars mission concepts and determined the appropriate role of science in a pro- gram of human exploration. Having laid this foundation, CHEX then evalu- ated and integrated the enabling requirements for human exploration con- tained in the strategy documents of relevant SSB committees. (The details of the individual scientific strategies and the goals of these SSB committees are, however, not repeated in this report they may be found in the original strategy documents listed in the bibliography.) These requirements were then classified according to their relevance to basic human survival and optimum mission performance. Information on the conditions necessary to maintain the well-being of humans in space was provided by the Committee on Space Biology and Medicine. Requirements for data on the properties of planetary atmospheres and surfaces and exobiology, needed for basic mission operations and sci

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PREFACE MIX once research, were supplied by the Committee on Planetary and Lunar Exploration. A Strategy for the Scientific Exploration of Mars (NASA, Jet Propulsion Laboratory, Pasadena, Calif., 1991), a report written by NASA's Mars Science Working Group, was consulted for additional information on the planetological and exobiological aspects of Mars precursor science. The space radiation environment, including its characterization and predictabil- ity, is the responsibility of the Committee on Solar and Space Physics and the Committee on Solar-Terrestrial Research. Advice on some technologi- cal issues was provided by the Committee on Microgravity Research. Full membership lists for these Space Studies Board discipline committees ap- pear in the appendix.

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44 SCIENTIFIC PREREQUISITES FOR THE HUMAN EXPLORATION OF SPACE 1. How to detect indigenous martian microorganisms and assess their biological activities; 2. How to recognize and analyze fossil remains of such indigenous . . microorganisms; 3. How to search for the presence of chemicals that might relate to past activities of life forms or that might relate to prebiotic chemistry; 4. Where to seek evidence for past life or prebiotic chemistry; and 5. How to detect the current, and understand the past, distribution of liquid water and ice. Beyond laboratory studies, answering these questions will involve ac- quiring a more detailed knowledge of Mars and its history. The location of ancient lake beds and of possible wind- and water-emplaced sediments will surely play a major role in selecting martian sites of interest to exobiolo- gists. The development of new organic analysis instrumentation with perhaps a 1000-fold improvement in sensitivity over the Viking mass spectrometer is likely to be needed. This needs to be coupled with a flexible "wet" chemistry input. If we are to adequately investigate the possible prehistory of biology on Mars, we need to answer whether or not there are any organic compounds of either abiogenic or biogenic origin on the surface or below the surface. Determining the ratios of different stereoisomers of amino acids will help distinguish between those of biogenic or abiogenic origin. RESOURCE UTILIZATION Long-term human exploration of Mars may require or greatly benefit from landing sites in close proximity to exploitable resources. If, for ex- ample, water needs to be acquired on Mars, it might be extracted from the air, from surface materials containing chemically bound water, or from sub- surface ice or permafrost. Which reservoir should be tapped depends on trade-offs between various extraction technologies available and detailed knowledge of the martian environment. The atmospheric abundance of water is known adequately for this purpose, but the location (particularly the depth) of subsurface ice is not. If there is a requirement to mine water at the landing site, then precur- sor flights should be designed to locate regions where subsurface ice may exist. Similarly, detailed knowledge of the local mineralogy should be obtained on precursor flights for in situ extraction of water from mined minerals. If habitation is chosen as a long-term goal of Mars exploration, then the technology necessary to locate subsurface water or permafrost will probably need to be developed.

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RESEARCH FOR MISSION OPTIMIZATION NOTES AND REFERENCES 45 1. Space Science Board, A Strategy for Space Biology and Medical Sciences for the 1980s and 1990s, National Academy Press, Washington, D.C., 1987, Chapter 4. 2. For an assessment of this problem in the context of Space Station Freedom, see Board on Environmental Studies and Toxicology, Guidelines for Developing Spacecraft Maxi- mum Allowable Concentrations for Space Station Contaminants, National Academy Press, Washington, D.C., 1992. 3. See Ref. 1, Chapter 2. 4. See Ref. 1, p. 32. 5. Mars Atmosphere Knowledge Requirements Working Group, SKI Engineering Re- quirements on Robotic Missions, Roger D. Bourke (ed.), JPLD-8465, NASA, Jet Propulsion Laboratory, Pasadena, Calif., May 1991.

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4 Conclusions The Committee on Human Exploration finds that a program for the exploration of the Moon and Mars by humans offers both challenges and opportunities for the participation of the scientific community. Foremost is the fact that particular, enabling scientific information is required if a Moon/ Mars program is ever to succeed in one of its prime goals, the expansion of human presence and human activity beyond Earth orbit into the solar sys- tem. This will remain the case even if a major Moon/Mars program is not initiated for 5 years or 25 years. The information that the committee deems critical is concerned largely with aspects of space biology and medicine and associated characteristics of the radiation environment. This in itself is not a new finding; recognition of the need for such information has been build- ing over the past 30 years with little progress on solutions. What is re- quired is that NASA (and other agencies involved in implementing a human exploration project) make a long-term commitment to sponsoring a rigor- ous, efficient, high-quality research program on the ground and in space. The resources required will be significant and challenge NASA to structure, market, implement, and ultimately manage an adequate plan. To enable long-duration human flight to, and operations on, the Moon and Mars, we must obtain critical relevant data. However, we must also consider ah initio that the enabling research has a purpose above and be- yond the simplistic, but prime, goal of achieving human presence and im- plied elementary survival. If a Moon/Mars program is to accomplish more than merely establishing a human presence in space, then achieving the 46

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CONCLUSIONS 47 program's yet-to-be-established specific goals and objectives demands that human performance and "pre-presence" preparation be optimized. This imperative places additional weight on the acquisition of scientific data on, for example, the distribution of potential lunar resources, details of the atmosphere of Mars, and information on the physical, chemical, and bio- logical properties of the martian surface. Science permeates all aspects of human exploration, no matter which architecture is finally selected and regardless of which set of candidate goals and objectives evolves. The involvement of the scientific community is needed to help set the goals for purely robotic missions, to analyze both scientific and engineering data, to structure appropriate tasks for humans, and to assist in the optimal integration of human and robotic activities. This pervasive requirement for scientific input mandates that the piloted spaceflight community develop a new understanding of and attention to the conduct of space science. It simultaneously requires that the scientific community interact constructively with those charged with implementation of a Moon/Mars program. In fact, success will require a technical and programmatic approach that eliminates the historical dichotomy between the "manned" and "unmanned" spaceflight programs.

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Bibliography Advisory Committee on the Future of the U.S. Space Program, Report of the Advisory Commit- tee on the Future of the U.S. Space Program, U.S. Government Printing Office, Washing- ton, D.C., 1990. Committee on Human Exploration of Space, Human Exploration of Space: A Review of NASA's 90-Day Study and Alternatives, National Academy Press, Washington, D.C., 1990. Committee on Space Policy, Toward a New Era in Space: Realigning Policies to New Reali- ties, National Academy Press, Washington, D.C., 1988. Mars Atmosphere Knowledge Requirements Working Group, SKI Engineering Requirements on Robotic Missions, Roger D. Bourke, (ed.), JPLD-8465, NASA, Jet Propulsion Labora- tory, Pasadena, Calif., May 1991. Mars Science Working Group, A Strategy for the Scientific Exploration of Mars, JPLD-8211, NASA, Jet Propulsion Laboratory, Pasadena, Calif., 1991. NASA Advisory Council, Exploring the Living Universe: A Strategy for Space Life Sciences, Report of the NASA Life Sciences Strategic Planning Study Committee, NASA, Wash- ington, D.C., 1988. NASA Advisory Council, Strategic Considerations for Support of Humans in Space and in Moon/Mars Exploration Missions, Vol. I & II, Life Sciences Research and Technology Programs, Aerospace Medicine Advisory Committee, NASA, Washington, D.C., 1992. NASA, Report of the 90-Day Study on Human Exploration of the Moon and Mars, NASA, Washington, D.C., 1989. National Commission on Space, Pioneering the Space Frontier, The Report of the National Commission on Space, Bantam Books, New York, 1986. National Council on Radiation Protection and Measurements, Guidance on Radiation Received in Space Activities, NCRP Report No. 98, National Council on Radiation Protection and Measurements, Bethesda, Maryland, 1989. Office of Exploration, Leadership and America's Future in Space, A Report to the Administra- tor by Dr. Sally K. Ride, August 1987, NASA, Washington, D.C., 1987. Office of Exploration, Beyond the Earth's Boundaries: Human Exploration of the Solar System in the 21st Century, NASA, Washington, D.C., 1988. 48

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BIBLIOGRAPHY 49 Office of Space Science and Applications, Cardiopulmonary Discipline Science Plan, Life Sciences Division, NASA, Washington, D.C., 1991. Office of Space Science and Applications, Controlled Ecological Life Support Systems (CELSS), Life Sciences Division, NASA, Washington, D.C., 1991. Office of Space Science and Applications, Developmental Biology Discipline Plan, Life Sci- ences Division, NASA, Washington, D.C., 1991. Office of Space Science and Applications, Human Factors Discipline Science Plan, Life Sci- ences Division, NASA, Washington, D.C., 1991. Office of Space Science and Applications, Musculoskeletal Discipline Science Plan, Life Sci- ences Division, NASA, Washington, D.C., 1991. Office of Space Science and Applications, Neuroscience Discipline Science Plan, Life Sci- ences Division, NASA, Washington, D.C., 1991. Office of Space Science and Applications, Regulatory Physiology Discipline Plan, Life Sci- ences Division, NASA, Washington, D.C., 1991. Office of Space Science and Applications, Space Biology Plant Program Plan, Life Sciences Division, NASA, Washington, D.C., 1991. Office of Space Science and Applications, Space Radiation Health Program Plan, Life Sci- ences Division, NASA, Washington, D.C., 1991. Office of Space Science and Applications, Space Life Sciences Strategic Plan, Life Sciences Division, NASA, Washington, D.C., 1992. Office of Technology Assessment, Exploring the Moon and Mars: Choices for the Nation, OTA-ISC-502, U.S. Government Printing Office, Washington, D.C., 1991. Space Environment Laboratory, Solar Radiation Forecasting and Research to Support the Space Exploration Initiative, NOAA Space Environment Laboratory, Boulder, Colo., 1991. Space Science Board, HZE-Particle Effects in Manned Spaceflight, National Academy of Sci- ences, Washington, D.C., 1973. Space Science Board, Post-Viking Biological Investigations of Mars, National Academy of Sciences, Washington, D.C., 1977. Space Science Board, Recommendations on Quarantine Policy for Mars, Jupiter, Saturn, Ura- nus, Neptune, and Titan, National Academy of Sciences, Washington, D.C., 1978. Space Science Board, Strategy for Exploration of the Inner Planets: 1977-1987, National Academy of Sciences, Washington, D.C., 1978. Space Science Board, Life Beyond the Earth's Environment: The Biology of Living Organisms in Space, National Academy of Sciences, Washington, D.C., 1979. Space Science Board, Origin and Evolution of Life-Implications for the Planets: A Scientific Strategy for the 1980's, National Academy of Sciences, Washington, D.C., 1981. Space Science Board, A Strategy for Space Biology and Medical Sciences for the 1980s and 1990s, National Academy Press, Washington, D.C., 1987. Space Science Board, Space Science in the Twenty-First Century: Imperatives for the Decades 1995 to 2015-Life Sciences, National Academy Press, Washington, D.C., 1988. Space Studies Board, International Cooperation for Mars Exploration and Sample Return, National Academy Press, Washington, D.C., 1990. Space Studies Board, 1990 Update to Strategy for the Exploration of the Inner Planets, Na- tional Academy Press, Washington, D.C., 1990. Space Studies Board, The Search for Life's Origins: Progress and Future Directions in Plan- etary Biology and Chemical Evolution, National Academy Press, Washington, D.C., 1990. Space Studies Board, Assessment of Programs in Space Biology and Medicine 1991, National Academy Press, Washington, D.C., 1991. Space Studies Board, Biological Contamination of Mars: Issues and Recommendations, Na- tional Academy Press, Washington, D.C., 1992. Synthesis Group, America at the Threshold, Report of the Synthesis Group on America's Space Exploration Initiative, U.S. Government Printing Office, Washington, D.C., 1991.

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Appendix COMMITTEE ON SPACE BIOLOGY AND MEDICINE FRED W. TUREK, Northwestern University, Chair ROBERT M. BERNE, University of Virginia, Charlottesville PETER DEWS, Harvard Medical School R.J. MICHAEL FRY, Oak Ridge National Laboratory FRANCIS (DREW) GAFFNEY, Southwestern Medical Center, Dallas EDWARD GOETZL, University of California Medical Center, San Francisco ROBERT HELMREICH, University of Texas, Austin JAMES LACKNER, Brandeis University BARRY W. PETERSON, Northwestern University CLINTON T. RUBIN, State University of New York, Stony Brook ALAN L. SCHILLER, Mt. Sinai Medical Center TOM SCOTT, University of North Carolina, Chapel Hill WARREN SINCLAIR, National Council on Radiation Protection and Measurements WILLIAM THOMPSON, North Carolina State University, Raleigh FRED WILT, University of California, Berkeley 51

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52 SCIENTIFIC PREREQUISITES FOR THE HUMAN EXPLORATION OF SPACE COMMITTEE ON SOLAR AND SPACE PHYSICS MARCIA NEUGEBAUER, Jet Propulsion Laboratory, Co-Chair THOMAS CRAVENS, University of Kansas JONATHAN F. ORMES, Goddard Space Flight Center GEORGE K. PARKS, University of Washington DOUGLAS M. RABIN, National Optical Astronomy Observatories DAVID M. RUST, Johns Hopkins University RAYMOND J. WALKER, University of California, Los Angeles YUK L. YUNG, California Institute of Technology RONALD D. ZWICKL, National Oceanic and Atmospheric Administration COMMITTEE ON SOLAR-TERRESTRIAL RESEARCH DONALD J. WILLIAMS, Applied Physics Laboratory, Co-Chair ALAN C. CUMMINGS, California Institute of Technology GORDON EMSLIE, University of Alabama DAVID C. FRITTS, University of Colorado ROLANDO R. GARCIA, National Center for Atmospheric Research MARGARET G. KIVELSON, University of California, Los Angeles DAVID J. McCOMAS, Los Alamos National Laboratory EUGENE N. PARKER, University of Chicago JAMES F. VICKREY, SRI International NOTE: The National Research Council's Committee on Solar-Terrestrial Research (CSTR) and Committee on Solar and Space Physics (CSSP) meet jointly as a federated committee and report directly to their parent National Research Council boards, the Board on Atmospheric Science and Climate for CSTR and the Space Studies Board for CSSP.

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APPENDIX COMMITTEE ON PLANETARY AND LUNAR EXPLORATION LARRY W. ESPOSITO, University of Colorado, Chair RETA BEEBE, New Mexico State University, Las Cruces ALAN P. BOSS, Carnegie Institution of Washington ANITA L. COCHRAN, University of Texas, Austin PETER J. GIERASCH, Cornell University WILLIAM S. KURTH, University of Iowa, Iowa City LUCY-ANN McFADDEN, University of Maryland CHRISTOPHER P. McKAY, NASA Ames Research Center DUANE O. MUHLEMAN, California Institute of Technology NORMAN R. PACE, Indiana University GRAHAM RYDER, Lunar and Planetary Institute PAUL D. SPUDIS, Lunar and Planetary Institute PETER H. STONE, Massachusetts Institute of Technology GEORGE WETHERILL, Carnegie Institution of Washington RICHARD W. ZUREK, Jet Propulsion Laboratory COMMITTEE ON MICROGRAVITY RESEARCH ROBERT F. SEKERKA, Carnegie Mellon University, Chairman ROBERT A. BROWN, Massachusetts Institute of Technology FRANKLIN D. LEMKEY, United Technologies Research Center WILLIAM A. SIRIGNANO, University of California, Irvine THOMAS A. STEITZ, Howard Hughes Medical Institute 53

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