SPACE NUCLEAR PROPULSION
for Human Mars Exploration
Space Nuclear Propulsion Technologies Committee
Aeronautics and Space Engineering Board
Division on Engineering and Physical Sciences
A Consensus Study Report of
THE NATIONAL ACADEMIES PRESS
Washington, DC
www.nap.edu
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This activity was supported by Contract No. NNH16CD01B/80HQTR20F0059 with the National Aeronautics and Space Administration. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.
International Standard Book Number-13: 978-0-309-68480-4
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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2021. Space Nuclear Propulsion for Human Mars Exploration. Washington, DC: The National Academies Press. https://doi.org/10.17226/25977.
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SPACE NUCLEAR PROPULSION TECHNOLOGIES COMMITTEE
ROBERT D. BRAUN, NAE,1 Jet Propulsion Laboratory, Co-Chair
ROGER M. MYERS, R. Myers Consulting, LLC, Co-Chair
SHANNON M. BRAGG-SITTON, Idaho National Laboratory
JONATHAN W. CIRTAIN, BWX Technologies, Inc.
TABITHA DODSON, Gryphon-Schafer Government Services, LLC
ALEC D. GALLIMORE, NAE, University of Michigan
JAMES H. GILLAND, Ohio Aerospace Institute
BHAVYA LAL, NASA Headquarters
PARVIZ MOIN, NAS2/NAE, Stanford University
JOSEPH A. SHOLTIS, JR., Sholtis Engineering & Safety Consulting
STEVEN J. ZINKLE, NAE, University of Tennessee, Knoxville
Staff
ALAN ANGLEMAN, Senior Program Officer, Study Director
COLLEEN N. HARTMAN, Director, Aeronautics and Space Engineering Board and Space Studies Board
GAYBRIELLE HOLBERT, Program Assistant
___________________
1 Member, National Academy of Engineering.
2 Member, National Academy of Sciences.
AERONAUTICS AND SPACE ENGINEERING BOARD
ALAN H. EPSTEIN, NAE,1 Chair, Pratt & Whitney (retired)
PAMELA A. MELROY, NAE, Melroy & Hollett Technology Partners, LLC, Vice Chair
BRIAN M. ARGROW, University of Colorado, Boulder
MEYER J. BENZAKEIN, NAE, The Ohio State University
ROBERT D. BRAUN, NAE, NASA Jet Propulsion Laboratory
EILEEN M. COLLINS, Space Presentations, LLC
EDWARD F. CRAWLEY, NAE, Massachusetts Institute of Technology
MICHAEL P. DELANEY, Boeing Commercial Airplanes
WILLIAM R. GRAY III, United States Air Force
SUSAN J. HELMS, NAE, Orbital Visions, LLC
JOHN C. KARAS, Aerospace Strategic Consulting
ILAN KROO, NAE, Stanford University
ANDREW R. LACHER, Noblis
NICHOLAS D. LAPPOS, Sikorsky, a Lockheed Martin Company
VALERIE MANNING, Airbus SAS
RICHARD MCKINNEY, RWMcKinney, LLC
PARVIZ MOIN, NAS2/NAE, Stanford University
ELLEN M. PAWLIKOWSKI, Independent Consultant
ROBIE I. SAMANTA ROY, Lockheed Martin Corporation
WANDA A. SIGUR, NAE, Independent Consultant
DAVID W. THOMPSON, NAE, Orbital ATK, Inc. (retired)
SHERRIE L. ZACHARIUS, The Aerospace Corporation (retired)
Staff
COLLEEN N. HARTMAN, Director
TANJA PILZAK, Manager, Program Operations
CELESTE A. NAYLOR, Information Management Associate
MARGARET A. KNEMEYER, Financial Officer
ANDREA REBHOLZ, Program Coordinator
RADAKA LIGHTFOOT, Financial Associate
___________________
1 Member, National Academy of Engineering.
2 Member, National Academy of Sciences.
Preface
NASA’s Space Technology Mission Directorate requested that the National Academies of Sciences, Engineering, and Medicine convene an ad hoc committee to identify primary technical and programmatic challenges, merits, and risks for developing and demonstrating space nuclear propulsion technologies of interest to future exploration missions. The particular systems of interest were specified as nuclear thermal propulsion and nuclear electric propulsion systems. The committee was also tasked with determining the key milestones, a top-level development and demonstration roadmap, and other missions that could be enabled by successful development of these systems.
The Aeronautics and Space Engineering Board of the National Academies’ Division on Engineering and Physical Sciences assembled a committee to carry out the assigned statement of task (see Appendix A). The committee members (see Appendix C) held 14 virtual meetings during 2020 and drafted this report based on inputs received during its public meetings, additional documents reviewed by the committee, and the expertise of the members. A list of all of the findings and recommendations that appear in the main body of the report can be found in Appendix B.
Robert D. Braun, Co-Chair
Roger M. Myers, Co-Chair
Space Nuclear Propulsion Technologies Committee
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Acknowledgment of Reviewers
This Consensus Study Report was reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the National Academies of Sciences, Engineering, and Medicine in making each published report as sound as possible and to ensure that it meets the institutional standards for quality, objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We thank the following individuals for their review of this report:
Douglas M. Allen, Schafer Corporation (retired),
Douglas M. Chapin, NAE,1 MPR Associates (retired),
Antonio Elias, NAE, Orbital ATK (retired),
Christopher F. McKee, NAS,2 University of California, Berkeley,
Kelsa Benensky Palomares, Analytical Mechanics Associates, Inc.,
Gerald Prudom, Consultant (retired),
Susan S. Voss, Global Nuclear Network Analysis, LLC, and
Edward L. (Ned) Wright, NAS, University of California, Los Angeles.
Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations of this report nor did they see the final draft before its release. The review of this report was overseen by William Kastenberg, NAE, University of California, Berkeley (retired), and Lester Lyles, NAE, Independent Consultant. They were responsible for making certain that an independent examination of this report was carried out in accordance with the standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content rests entirely with the authoring committee and the National Academies.
___________________
1 Member, National Academy of Engineering.
2 Member, National Academy of Sciences.
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Contents
1 INTRODUCTION AND BASELINE MISSION REQUIREMENTS
Baseline Mission to Mars: Crewed Opposition-Class Missions
Propulsion System Requirements
Technology Requirements, Risks, and Options
Testing, Modeling, and Simulation
Development and Demonstration Roadmap
Technology Requirements, Risks, and Options
Testing, Modeling, and Simulation
4 SYSTEM AND PROGRAMMATIC ISSUES
NTP and NEP Are Different Technologies
Developments Common to Both NTP and NEP Systems
Lessons Learned from the History of Developing Space Nuclear Systems
Potential for Higher Performance Space Nuclear Propulsion Systems
Surface Power Use of NEP Reactors
Synergies with National Security Missions
Synergies with Terrestrial Nuclear Systems
A Statement of Task and Additional Guidance
B Findings and Recommendations