Origins, Worlds, and Life
A Decadal Strategy for Planetary Science and Astrobiology 2023–2032
Committee on the Planetary Science and Astrobiology Decadal Survey
Space Studies Board
Division on Engineering and Physical Sciences
A Consensus Study Report of
THE NATIONAL ACADEMIES PRESS
Washington, DC
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This study is based on work supported by Contract No. NNH17CB02B/NNH17CB01T with the National Aeronautics and Space Administration and Grant No. 2040016 with the National Science Foundation. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any agency or organization that provided support for the project.
International Standard Book Number-13: 978-0-309-47578-5
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Images: Foreground waves: Conrad Ziebland; protoplanetary disk: ESO/L. Calçada; Saturn: NASA; Earth: ESA/OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA/Gordan Ugarković; magma ocean world: ESA/Hubble, M. Kornmesser; comet: NASA/ESA/Hubble Heritage Team (STScI-AURA); hydrothermal vent: MARUM–Zentrum für Marine Umweltwissenschaften, Universität Bremen; starfield: ESO/S. Brunier.
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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2023. Origins, Worlds, and Life: A Decadal Strategy for Planetary Science and Astrobiology 2023–2032. Washington, DC: The National Academies Press. https://doi.org/10.17226/26522.
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COMMITTEE ON THE PLANETARY SCIENCE AND ASTROBIOLOGY DECADAL SURVEY
Steering Group
ROBIN M. CANUP, NAS,1 Southwest Research Institute, Co-Chair
PHILIP R. CHRISTENSEN, Arizona State University, Co-Chair
MAHZARIN R. BANAJI, NAS, Harvard University
STEVEN J. BATTEL, NAE,2 Battel Engineering
LARS E. BORG, Lawrence Livermore National Laboratory
ATHENA COUSTENIS, National Centre for Scientific Research, Paris Observatory
JAMES H. CROCKER, NAE, Lockheed Martin Space Systems Company
BRETT W. DENEVI, Johns Hopkins University Applied Physics Laboratory
BETHANY L. EHLMANN, California Institute of Technology
LARRY W. ESPOSITO, University of Colorado Boulder
ORLANDO FIGUEROA, Orlando Leadership Enterprise
JOHN M. GRUNSFELD, Endless Frontier Associates
JULIE HUBER, Woods Hole Oceanographic Institution
KRISHAN KHURANA, University of California, Los Angeles
WILLIAM B. McKINNON, Washington University in St. Louis
FRANCIS NIMMO, NAS, University of California, Santa Cruz
CAROL RAYMOND, Jet Propulsion Laboratory
BARBARA SHERWOOD LOLLAR, NAS/NAE, University of Toronto
AMY SIMON, NASA Goddard Space Flight Center
Panel on Giant Planet Systems
JONATHAN I. LUNINE, NAS, Cornell University, Chair
AMY SIMON, NASA Goddard Space Flight Center, Vice Chair
FRANCES BAGENAL, NAS, University of Colorado Boulder
RICHARD W. DISSLY, Ball Aerospace and Technologies Corporation
LEIGH N. FLETCHER, University of Leicester
TRISTAN GUILLOT, Nice Observatory
MATTHEW HEDMAN, University of Idaho
RAVIT HELLED, University of Zurich
KATHLEEN E. MANDT, Johns Hopkins University Applied Physics Laboratory
ALYSSA RHODEN, Southwest Research Institute
PAUL M. SCHENK, Lunar and Planetary Institute
MICHAEL H. WONG, SETI Institute
Panel on Mars
VICTORIA E. HAMILTON, Southwest Research Institute, Chair
BETHANY L. EHLMANN, California Institute of Technology, Vice Chair
WILLIAM B. BRINCKERHOFF, NASA Goddard Space Flight Center
TRACY K.P. GREGG, University of Buffalo
JASPER S. HALEKAS, University of Iowa
JOHN “JACK” W. HOLT, University of Arizona
JOEL HUROWITZ, Stony Brook University
___________________
1 Member, National Academy of Sciences.
2 Member, National Academy of Engineering.
BRUCE M. JAKOSKY, University of Colorado Boulder
MICHAEL MANGA, NAS, University of California, Berkeley
HARRY Y. MCSWEEN, NAS, University of Tennessee
CLAIRE E. NEWMAN, Aeolis Research
ALEJANDRO M. SAN MARTIN, NAE, Jet Propulsion Laboratory
KIRSTEN L. SIEBACH, Rice University
AMY WILLIAMS, University of Florida
ROBIN D. WORDSWORTH, Harvard University
Panel on Mercury and the Moon
TIMOTHY L. GROVE, NAS, Massachusetts Institute of Technology, Chair
BRETT W. DENEVI, Johns Hopkins University Applied Physics Laboratory, Vice Chair
JAMES DAY, University of California, San Diego
ALEXANDER J. EVANS, Brown University
SARAH FAGENTS, University of Hawaii at Manoa
WILLIAM M. FARRELL, NASA Goddard Space Flight Center
CALEB I. FASSETT, NASA Marshall Space Flight Center
JENNIFER L. HELDMANN, NASA Ames Research Center
MASATOSHI HIRABAYASHI, Auburn University
JAMES TUTTLE KEANE, Jet Propulsion Laboratory
FRANCIS MCCUBBIN, NASA Johnson Space Center
MIKI NAKAJIMA, University of Rochester
MARK P. SAUNDERS, Independent Consultant
SONIA M. TIKOO-SCHANTZ, Stanford University
Panel on Ocean Worlds and Dwarf Planets
ALEXANDER G. HAYES, Cornell University, Chair
FRANCIS NIMMO, NAS, University of California, Santa Cruz, Vice Chair
MORGAN L. CABLE, Jet Propulsion Laboratory
ALFONSO DAVILA, NASA Ames Research Center
GLEN FOUNTAIN, Johns Hopkins University Applied Physics Laboratory
CHRISTOPHER R. GERMAN, Woods Hole Oceanographic Institution
CHRISTOPHER R. GLEIN, Southwest Research Institute
CANDICE HANSEN, Planetary Science Institute
EMILY S. MARTIN, National Air and Space Museum, Smithsonian Institution
MARC NEVEU, University of Maryland
CAROL S. PATY, University of Oregon
LYNNAE C. QUICK, NASA Goddard Space Flight Center
JASON M. SODERBLOM, Massachusetts Institute of Technology
KRISTA M. SODERLUND, University of Texas Institute for Geophysics
Panel on Small Solar System Bodies
NANCY L. CHABOT, Johns Hopkins University Applied Physics Laboratory, Chair
CAROL RAYMOND, Jet Propulsion Laboratory, Vice Chair
PAUL A. ABELL, NASA Johnson Space Center
WILLIAM F. BOTTKE, Southwest Research Institute
HAROLD C. CONNOLLY, JR., Rowan University
THOMAS D. JONES, Association of Space Explorers
STEFANIE N. MILAM, NASA Goddard Space Flight Center
EDGARD G. RIVERA-VALENTÍN, Lunar and Planetary Institute
DANIEL J. SCHEERES, NAE, University of Colorado Boulder
RHONDA STROUD, Naval Research Laboratory
MEGAN BRUCK SYAL, Lawrence Livermore National Laboratory
MYRIAM TELUS, University of California, Santa Cruz
AUDREY THIROUIN, Lowell Observatory
CHAD TRUJILLO, Northern Arizona University
BENJAMIN P. WEISS, Massachusetts Institute of Technology
Panel on Venus
PAUL K. BYRNE, Washington University in St. Louis, Chair
LARRY W. ESPOSITO, University of Colorado, Vice Chair
GIADA N. ARNEY, NASA Goddard Space Flight Center
AMANDA S. BRECHT, NASA Ames Research Center
THOMAS E. CRAVENS, University of Kansas
KANDIS-LEA JESSUP, Southwest Research Institute
JAMES F. KASTING, NAS, The Pennsylvania State University
SCOTT D. KING, Virginia Polytechnic Institute and State University
BERNARD MARTY, Université de Lorraine
THOMAS NAVARRO, University of California, Los Angeles
JOSEPH G. O’ROURKE, Arizona State University
JENNIFER M. ROCCA, Jet Propulsion Laboratory
ALISON R. SANTOS, Wesleyan University
JENNIFER L. WHITTEN, Tulane University
Staff
DAVID H. SMITH, Senior Program Officer, Space Studies Board, Study Director
DWAYNE A. DAY, Senior Program Officer, Aeronautics and Space Engineering Board
DANIEL NAGASAWA, Program Officer, Space Studies Board
JORDYN WHITE, Program Officer, Committee on National Statistics
CARL-GUSTAV ANDERSON, Associate Program Officer, Board on Mathematical Sciences and Analytics
MIA BROWN, Research Associate, Space Studies Board
MEGAN A. CHAMBERLAIN, Senior Program Assistant, Space Studies Board
GAYBRIELLE HOLBERT, Program Assistant, Space Studies Board
DIONNA ALI, Associate Program Officer, Intelligence Community Studies Board
ELI NASS, Research Assistant, Division on Engineering and Physical Sciences
KATHERINE DZURILLA, Temporary Research Assistant, Space Studies Board
LUCIA ILLIARI, Temporary Research Assistant, Space Studies Board
JEAN DE BECDELIEVRE, Christine C. Mirzayan Science and Technology Policy Fellow (2021)
JACOB N.H. ABRAHAMS, Lloyd V. Berkner Space Policy Intern (2021)
TARINI KONCHADY, Lloyd V. Berkner Space Policy Intern (2021)
DYLAN PITTS, Lloyd V. Berkner Space Policy Intern (2023)
COLLEEN N. HARTMAN, Director, Space Studies Board
SPACE STUDIES BOARD
MARGARET G. KIVELSON, NAS, University of California, Los Angeles, Chair
GREGORY P. ASNER, NAS, Carnegie Institution for Science
ADAM BURROWS, NAS, Princeton University
JAMES H. CROCKER, NAE, Lockheed Martin Space Systems Company (retired)
JEFF DOZIER, University of California, Santa Barbara
M. DARBY DYAR, Mount Holyoke College
ANTONIO L. ELIAS, NAE, Orbital ATK (retired)
VICTORIA E. HAMILTON, Southwest Research Institute
DENNIS P. LETTENMAIER, NAE, University of California, Los Angeles
ROSALY M. LOPES, Jet Propulsion Laboratory
STEPHEN J. MACKWELL, American Institute of Physics
DAVID J. MCCOMAS, Princeton University
LARRY J. PAXTON, Johns Hopkins University
ELIOT QUATAERT, University of California, Berkeley
MARK SAUNDERS, Independent Consultant
BARBARA SHERWOOD LOLLAR, NAS/NAE, University of Toronto
HOWARD SINGER, National Oceanic and Atmospheric Administration
ERIKA B. WAGNER, Blue Origin
PAUL D. WOOSTER, Space Exploration Technologies
EDWARD L. WRIGHT, NAS, University of California, Los Angeles
Staff
COLLEEN N. HARTMAN, Director
CARMELA J. CHAMBERLAIN, Administrative Coordinator
TANJA PILZAK, Manager, Program Operations
CELESTE A. NAYLOR, Information Management Associate
MARGARET KNEMEYER, Financial Officer
Preface
The Planetary Science Division (PSD) of NASA’s Science Mission Directorate (SMD) is the primary source of funding for planetary science, astrobiology, and planetary defense activities in the United States. In addition, the National Science Foundation (NSF) provides modest, but highly important, support for a variety of supporting ground-based activities, most notably access to world-class, ground-based optical and radio telescopes.
The allocation of resources within and among spacecraft missions, supporting research activities, and technology development is determined to a major extent via a relatively mature strategic planning process that relies heavily on inputs from the scientific community to establish the scientific basis and direction for its space-science flight- and ground-research programs and technology development activities.
The primary sources of this guidance are the independent scientific analyses and recommendations provided by reports of the National Academies of Sciences, Engineering, and Medicine (e.g., by the Space Studies Board [SSB] and its committees) and, to a lesser extent, by parallel inputs coming from community-based, but NASA-organized, analysis/assessment groups (e.g., the Mars Exploration Program Analysis Group and the Outer Planets Assessment Group). The science strategies developed by the SSB and the analysis/assessment groups form input to subsequent program development activities conducted by the FACA-chartered NASA Advisory Council and its associated committees (e.g., NASA’s Planetary Science Advisory Committee).
The SSB’s primary vehicles for the provision of strategic advice to NASA are the space science decadal surveys. The National Academies decadal surveys are widely recognized among policymakers and program managers as key resources in determining where a field of research is and where it is headed. Indeed, the decadal survey process has proved so useful that Section 1104 of the NASA Authorization Act of 2008 requires that the NASA “Administrator shall enter into agreements on a periodic basis with the National Academies for independent assessments, also known as decadal surveys, to take stock of the status and opportunities for Earth and space science discipline fields and aeronautics research and to recommend priorities for research and programmatic areas over the next decade.”
The most recent effort for planetary science and astrobiology resulted in the publication of Vision and Voyages for Planetary Science in the Decade 2013–2022 in 2011. While it is generally regarded that Vision and Voyages was especially successful in its outcomes—as witnessed by the facts that the survey’s top two large-class mission priorities are both under development and that PSD’s annual budget has doubled over the past decade—a new survey is needed to address the challenges of the coming decade.
Following informal requests in the early months of 2019 from the director of PSD, the SSB and its Committee on Astrobiology and Planetary Science (CAPS) began the task of defining the specific actions and issues that
needed to be address in a new decadal survey. CAPS’s activities culminated in the convening of a decadal survey organizing meeting, held at the California Institute of Technology’s Keck Institute for Space Studies in September 2019. Negotiations between NASA and the SSB continued through the final months of 2019 and eventually settled on a statement of task calling for a decadal survey that provided a clear exposition of the following:1
- An overview of planetary science, astrobiology, and planetary defense: what they are, why they are compelling undertakings, and the relationship between space- and ground-based research.
- A broad survey of the current state of knowledge of the solar system.
- The most compelling science questions, goals, and challenges that should motivate future strategy in planetary science, astrobiology, and planetary defense.
- A coherent and consistent traceability of recommended research and missions to objectives and goals.
- A comprehensive research strategy to advance the frontiers of planetary science, astrobiology, and planetary defense during the period 2023–2032 that will include identifying, recommending, and ranking the highest priority research activities (research activities include any project, facility, experiment, mission, or research program of sufficient scope to be identified separately in the final report). For each activity, consideration should be given to the scientific case, international and private landscape, timing, cost category and cost risk, as well as technical readiness, technical risk, lifetime, and opportunities for partnerships. The strategy should be balanced by consideration of large, medium, and small research activities for both ground and space.
- Recommendations for decision rules, where appropriate, for the comprehensive research strategy that can accommodate significant but reasonable deviations in the projected budget or changes in urgency precipitated by new discoveries or technological developments.
- An awareness of the science and space mission plans and priorities of NASA human space exploration programs and potential foreign and U.S. agency partners reflected in the comprehensive research strategy and identification of opportunities for cooperation, as appropriate.
- The opportunities for collaborative research that are relevant to science priorities among SMD’s four science divisions (for example, comparative planetology approaches to exoplanet or astrobiology research); between NASA SMD and the other NASA mission directorates; between NASA and the NSF; between NASA and other U.S. government entities; between NASA and private sector organizations; and between NASA and its international partners.
- The state of the profession, including issues of diversity, inclusion, equity, and accessibility; the creation of safe workspaces; and recommended policies and practices to improve the state of the profession. Where possible, provide specific, actionable, and practical recommendations to the agencies and community to address these areas.
In response to this request, the National Academies established the Committee on the Planetary Science and Astrobiology Decadal Survey (hereafter, the “survey committee” or the “committee”) consisting of a 19-member steering group and 78 additional experts organized into six topical panels. The co-chairs of the survey committee were appointed in May 2020, and the members of the panels were identified and appointed in the subsequent spring and summer months.
The steering group held its first meeting on September 30, 2020, and held its 22nd and final meeting on November 2, 2021. The six panels each held at least 20 meetings during the period October 2020 to September 2021. Notably, each and every single meeting was held virtually because of the ongoing COVID-19 pandemic. The work of the survey committee can be divided into three distinct phases: the last 3 months of 2020, the first 9 months of 2021, and late summer/early autumn of 2021.
In phase one, the steering group deliberated on and defined the key science questions around which the report would be structured. In parallel, the panels ingested and assessed candidate missions already studied, and identified additional concepts deemed worthy of study. Phase one ended with the development of two key items: first, a cross-survey consensus that the most appropriate key questions had been identified, and second, the prioritization
___________________
1 See Appendix A for the letter requesting this study, the full text of the statement of task, and additional, nonbinding guidelines.
by the steering group of 10 new mission concepts worthy of additional study. These 10 new concepts were subsequently forwarded to NASA for detailed study. To ensure that the panels would perform their initial task in an expeditious manner, they were organized and appointed so that each would have responsibility for different portions of the solar system—that is, Mercury and the Moon, Venus, Mars, giant planet systems, ocean worlds and dwarf planets, and small solar system bodies.
During the second phase, the panels worked with mission-design teams at the Jet Propulsion Laboratory, NASA Goddard Space Flight Center, and at the Johns Hopkins University Applied Physics Laboratory to develop the 10 new mission concepts. In parallel, a series of approximately 20 informal, cross-survey writing groups—each consisting of 5–10 members from the steering group and the panels—were established to create the initial drafts of the chapters in this report devoted to the key science questions and to programmatic issues such as the state of the profession, research and analysis, and technology development. Once the additional mission studies were completed, their sponsoring panels performed a comparative assessment of the degree to which the new concepts and other proposed and studied missions could address the survey’s key science questions. This phase of the survey ended with the completion of the initial drafts of 20 of this report’s 23 chapters and the prioritization by the steering group of 17 mission concepts (some new and some old) for detailed technical risk and cost evaluation (TRACE) by the Aerospace Corporation.
Phase three involved the scheduling of some 20 survey-wide “summit meetings,” during which the text produced by each writing group was subjected to intense comment, review, and subsequent revision. In parallel, the steering group assessed the results of the TRACE analyses, selected the most promising ones, prioritized them, and, thus, established the survey’s list of recommended mission activities for the coming decade. In addition, the steering group worked with the leaders of each writing group to integrate the draft text of the various chapters into a self-consistent and coherent program of activities for the next decade. The final task performed was the drafting by the steering group of the summary and the chapter describing the recommended program of activities for the period 2023–2032.
Final sections of the report were drafted, assembled, and integrated in October and November 2021. The text was sent to external reviewers in December, was revised between January and February 2022, was formally approved for release by the National Academies on March 24, 2022, and was publicly unveiled on April 19, 2022.
The work of the committee was made easier thanks to the important help given by individuals too numerous to list—indeed, printing just the names of those individuals who made public presentations to the survey committee would require two full pages of text—at a variety of public and private organizations, who made presentations at committee meetings, drafted white papers, and participated in mission studies. Important contributions were also made by the TRACE team at the Aerospace Corporation, led by Russell Persinger, Justin Yoshida, and Mark Barrera. Last, the survey committee thanks Kellie Mendelow for her invaluable record keeping, file management, and editorial assistance.
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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:
___________________
1 Member, National Academy of Sciences.
2 Member, National Academy of Medicine.
Although the reviewers listed above have 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 Rosaly M. Lopes, Jet Propulsion Laboratory, and Norman H. Sleep, NAS, Stanford University. 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 of the report rests entirely with the authoring committee and the National Academies.
___________________
3 Member, National Academy of Engineering.
Contents
1 INTRODUCTION TO PLANETARY SCIENCE, ASTROBIOLOGY, AND PLANETARY DEFENSE
Planetary Science and Astrobiology
The Relationship Between Ground- and Space-Based Research
Support for Planetary Science and Astrobiology
Planetary Science Decadal Surveys and Related Reports
Scientific Scope of This Report
A Guide to Reading This Report
2 TOUR OF THE SOLAR SYSTEM: A TRANSFORMATIVE DECADE OF EXPLORATION
4 QUESTION 1: EVOLUTION OF THE PROTOPLANETARY DISK
Q1.1 What Were the Initial Conditions in the Solar System?
Q1.2 How Did Distinct Reservoirs of Gas and Solids Form and Evolve in the Protoplanetary Disk?
Q1.3 What Processes Led to the Production of Planetary Building Blocks—That Is, Planetesimals?
Q1.4 How and When Did the Nebula Disperse?
Supportive Activities for Question 1
5 QUESTION 2: ACCRETION IN THE OUTER SOLAR SYSTEM
Q2.1 How Did the Giant Planets Form?
Q2.2 What Controlled the Compositions of the Material That Formed the Giant Planets?
Q2.3 How Did Satellites and Rings Form Around the Giant Planets During the Accretion Era?
Supportive Activities for Question 2
6 QUESTION 3: ORIGIN OF EARTH AND INNER SOLAR SYSTEM BODIES
Q3.1 How and When Did Asteroids and Inner Solar System Protoplanets Form?
Q3.2 Did Giant Planet Formation and Migration Shape the Formation of the Inner Solar System?
Q3.3 How Did the Earth–Moon System Form?
Q3.4 What Processes Yielded Mars, Venus, and Mercury and Their Varied Initial States?
Q3.5 How and When Did the Terrestrial Planets and Moon Differentiate?
Supportive Activities for Question 3
7 QUESTION 4: IMPACTS AND DYNAMICS
Q4.2 How Did Impact Bombardment Vary with Time and Location in the Solar System?
8 QUESTION 5: SOLID BODY INTERIORS AND SURFACES
Q5.1 How Diverse Are the Compositions and Internal Structures Within and Among Solid Bodies?
Q5.2 How Have the Interiors of Solid Bodies Evolved?
Q5.6 What Drives Active Processes Occurring in the Interiors and on the Surfaces of Solid Bodies?
Supportive Activities for Question 5
9 QUESTION 6: SOLID BODY ATMOSPHERES, EXOSPHERES, MAGNETOSPHERES, AND CLIMATE EVOLUTION
Q6.1 How Do Solid Body Atmospheres Form and What Was Their State During and Shortly After Accretion?
Q6.3 What Processes Drive the Dynamics and Energetics of Atmospheres on Solid Bodies?
Q6.4 How Do Planetary Surfaces and Interiors Influence and Interact with Their Host Atmospheres?
Q6.5 What Processes Govern Atmospheric Loss to Space?
10 QUESTION 7: GIANT PLANET STRUCTURE AND EVOLUTION
Q7.1 What Are Giant Planets Made of and How Can This Be Inferred from Their Observable Properties?
Q7.3 What Governs the Diversity of Giant Planet Climates, Circulation, and Meteorology?
Q7.5 How Are Giant Planets Influenced by, and How Do They Interact with, Their Environment?
Supportive Activities for Question 7
11 QUESTION 8: CIRCUMPLANETARY SYSTEMS
Q8.1 How Did Circumplanetary Systems Form and Evolve over Time to Yield Different Planetary Systems?
Q8.2 How Do Tides and Other Endogenic Processes Shape Planetary Satellites?
Q8.3 What Exogenic Processes Modify the Surfaces of Bodies in Circumplanetary Systems?
Q8.4 How Do Planetary Magnetospheres Interact with Satellites with Rings, and Vice Versa?
Q8.5 How Do Rings Evolve and Coalesce into Moons?
12 QUESTION 9: INSIGHTS FROM TERRESTRIAL LIFE
13 QUESTION 10: DYNAMIC HABITABILITY
Q10.2 Where Are or Were the Solar System’s Past or Present Habitable Environments?
Q10.3 Water Availability: What Controls the Amount of Available Water on a Body over Time?
Q10.5 What Is the Availability of Nutrients and Other Inorganic Ingredients to Support Life?
Q10.6 What Controls the Energy Available for Life?
Q10.7 What Controls the Continuity or Sustainability of Habitability?
Supportive Activities for Question 10
14 QUESTION 11: SEARCH FOR LIFE ELSEWHERE
Q11.3 Life Detection: Is or Was There Life Elsewhere in the Solar System?
Q11.4 Life Characterization: What Is the Nature of Life Elsewhere, If It Exists?
Q12.1 Evolution of the Protoplanetary Disk
Q12.2 Accretion in the Outer Solar System
Q12.3 Origin of Earth and Inner Solar System Bodies
Q12.5 Solid Body Interiors and Surfaces
Q12.6 Atmosphere and Climate Evolution on Solid Bodies
Q12.7 Giant Planet Structure and Evolution
Q12.9 Insights from Terrestrial Life
Q12.11 Search for Life Elsewhere
White Papers Submitted to the Survey
The Internal Scientist Funding Model
Virtual Institutes and Research Coordination Networks
Is the R&A Portfolio Optimized for NASA’s Scientific Needs?
Trends in PSD R&A Funding and Programs Through Time
Recommended Funding for NASA Planetary R&A
The Size of the Planetary Research Community
18 PLANETARY DEFENSE: DEFENDING EARTH THROUGH APPLIED PLANETARY SCIENCE
NEO Detection, Tracking, and Characterization
NEO Modeling, Prediction, and Information Integration
NEO Deflection and Disruption Missions
International Cooperation on NEO Preparation
NEO Impact Emergency Procedures and Action Protocols
The Pivotal Role of Science in Human Exploration
Science Enabled by Human Explorers
Near-Term Human Exploration Plans, Relationship to Science, and In Situ Resource Utilization
Integrating Science into Human Exploration
Scientific and Human Exploration of Mars
A Tale of Two Orbiters: LRO and IMIM
Research Programs to Enable and Optimize Human Exploration
Role of Commercial Space and Human-Scale Vehicle Capabilities
20 INFRASTRUCTURE FOR PLANETARY SCIENCE AND EXPLORATION
Technology Development in NASA
Technologies for This Decade and Beyond
Disruptive and Game-Changing Trends in Technologies
22 RECOMMENDED PROGRAM: 2023–2032
Scientific Themes and Priority Science Questions
Ongoing Missions and Existing Programs
Discovery, New Frontiers, and Flagship Recommendations for the Decade 2023–2032
Representative Flight Programs for the Decade
Other Key Programmatic Recommendations
Preparing for the Next Decadal Survey
A Letter of Request, Statement of Task, and Other Guidance
C Technical Risk and Cost Evaluation of Priority Missions
D Missions Studied but Not Sent for TRACE
Dedication
This report is dedicated to the memory of H. Jay Melosh (1947–2020)
who had agreed to play an important role in this study.
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