Planetary Protection Considerations
for Missions to Solar System Small
Bodies

Report Series—Committee on Planetary Protection

_____

Committee on Planetary Protection

Space Studies Board

Division on Engineering and
Physical Sciences

Board on Life Sciences

Division on Earth and Life Studies

Consensus Study Report

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This study is based on work supported by Contract NNH17CB02B/NNH17CB01T 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 agency or organization that provided support for the project.

International Standard Book Number-13: 978-0-309-69372-1
International Standard Book Number-10: 0-309-69372-1
Digital Object Identifier: https://doi.org/10.17226/26714

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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2023. Planetary Protection Considerations for Missions to Small Bodies in the Solar System: Report Series—Committee on Planetary Protection. Washington, DC: The National Academies Press. https://doi.org/10.17226/26714.

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COMMITTEE ON PLANETARY PROTECTION

JOSEPH K. ALEXANDER, Alexander Space Policy Consultants, Co-Chair

AMANDA R. HENDRIX, Planetary Science Institute, Co-Chair

ANGEL ABBUD-MADRID, Colorado School of Mines

ANTHONY COLAPRETE, NASA Ames Research Center

MICHAEL J. DALY, Uniformed Services University of the Health Sciences

DAVID P. FIDLER, Council on Foreign Relations

SARAH A. GAVIT, Jet Propulsion Laboratory

ANDREW D. HORCHLER, Astrobotic Technology, Inc.

EUGENE H. LEVY, Rice University

ROBERT E. LINDBERG, JR., Independent Consultant

MARGARITA M. MARINOVA,¹ Project Kuiper

A. DEANNE ROGERS, Stony Brook University, The State University of New York

GERHARD H. SCHWEHM, European Space Agency (retired)

TRISTA J. VICK-MAJORS, Michigan Technological University

Staff

DANIEL NAGASAWA, Program Officer, Space Studies Board, Study Director

NANCY CONNELL, Senior Scientist, Board on Life Sciences

ALEXANDER BELLES, Mirzayan Science & Technology Policy Graduate Fellow, Space Studies Board

MEGAN CHAMBERLAIN, Senior Program Assistant, Space Studies Board

COLLEEN N. HARTMAN, Director, Space Studies Board and Aeronautics and Space Engineering Board

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¹ Recused from this study.

SPACE STUDIES BOARD

MARGARET G. KIVELSON (NAS), University of California, Los Angeles, Chair

JAMES H. CROCKER (NAE), Lockheed Martin Space Systems Company (retired), Vice Chair

GREGORY P. ASNER (NAS), Carnegie Institution for Science

ADAM BURROWS (NAS), Princeton University

DANIELA CALZETTI (NAS), University of Massachusetts Amherst

JEFF DOZIER, University of California, Santa Barbara

MELINDA D. DYAR, Mount Holyoke College

ANTONIO ELIAS, Orbital ATK, Inc. (retired)

VICTORIA 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

J. MARSHALL SHEPARD (NAS/NAE), University of Georgia

BARBARA SHERWOOD LOLLAR, University of Toronto

HOWARD SINGER, National Oceanic and Atmospheric Administration

HARLAN E. SPENCE, University of New Hampshire

ERIKA B. WAGNER, Blue Origin, LLC

PAUL D. WOOSTER, Space Exploration Technologies

EDWARD L. WRIGHT (NAS), University of California, Los Angeles

ENDAWOKE YIZENGAW, The Aerospace Corporation

Staff

COLLEEN N. HARTMAN, Director

TANJA PILZAK, Manager, Program Operations

CELESTE A. NAYLOR, Information Management Associate

MARGARET A. KNEMEYER, Financial Officer

RADAKA LIGHTFOOT, Financial Associate

BOARD ON LIFE SCIENCES

BARBARA A. SCHAAL (NAS), Washington University in St. Louis, Chair

A. ALONSO AGUIRRE, George Mason University

VALERIE H. BONHAM, Ropes & Gray LLP

DOMINIQUE BROSSARD, University of Wisconsin–Madison

SEAN M. DECATUR, Kenyon College

SCOTT V. EDWARDS (NAS), Harvard University

GERALD L. EPSTEIN, National Defense University

ROBERT J. FULL, University of California, Berkeley

ROBERT NEWMAN, The Aspen Institute

STEPHEN J. O’BRIEN (NAS), Nova Southeastern University

LUCILA OHNO-MACHADO (NAM), University of California, San Diego

CLAIRE POMEROY (NAM), Albert and Mary Lasker Foundation

SUSAN RUNDELL SINGER, Rollins College

DAVID R. WALT (NAE/NAM), Harvard Medical School

PHYLLIS M. WISE (NAM), University of Colorado

Staff

KAVITA BERGER, Director

FRAN SHARPLES, Advisor

JO HUSBANDS, Scholar and Senior Project Director

NANCY D. CONNELL, Senior Scientist

STEVEN MOSS, Program Officer

AUDREY THÉVENON, Program Officer

MATTHEW ANDERSON, Financial Business Partner

JESSICA DE MOUY, Senior Program Assistant

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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:

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 A. Thomas Young (NAE), Lockheed Martin Corporation (retired), and Melissa A. McGrath, SETI Institute. 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.

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Contents

PREFACE

EXECUTIVE SUMMARY

1 INTRODUCTION

2 SMALL BODIES: BACKGROUND AND CONSIDERATIONS

3 CRITERIA FOR PLANETARY PROTECTION CATEGORIZATION OF SMALL BODY MISSIONS

4 IMPLICATIONS OF PLANETARY PROTECTION CATEGORY I VERSUS CATEGORY II FOR SMALL BODY MISSIONS

5 PLANETARY PROTECTION, SMALL SOLAR SYSTEM BODIES, AND COMMERCIAL SPACE ACTIVITIES

APPENDIXES

A Statement of Task

B COSPAR Planetary Protection Requirements for Category I and Category II Missions

C Acronyms and Abbreviations

D Committee and Staff Biographies

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Preface

The Space Studies Board (SSB; and its predecessor, the Space Science Board) of the National Academies of Sciences, Engineering, and Medicine has been involved in shaping the U.S. planetary protection policy for 60 years. Through those years, the National Aeronautics and Space Administration (NASA) has sponsored studies through the SSB, seeking independent, scientific advice on how to craft its planetary protection policies. NASA’s policies, in turn, have formed a basis upon which the global space science community has developed consensus international planetary protection policies through the International Council for Science’s Committee on Space Research (COSPAR).

In 2016, NASA asked the SSB to perform a study on the development of planetary protection policies. The resultant report, Review and Assessment of Planetary Protection Policy Development Processes, was released in 2018, followed by a separate 2019 report of NASA’s Planetary Protection Independent Review Board.¹ Both studies concluded that there was a need for NASA to “reestablish an independent and appropriate advisory body and process to help guide formulation and implementation of planetary protection adequate to serve the best interests of the public, the NASA program, and the variety of new entrants that may become active in deep space operations in the years ahead.”² At NASA’s request, the newest discipline committee of the SSB was formed in July 2020, the Committee on Planetary Protection (CoPP), to serve as the standing forum for the discussion of planetary protection issues critical to NASA.

For the committee’s third report, NASA’s Science Mission Directorate and Office of Safety and Mission Assurance leadership requested that the CoPP draft a report discussing the planetary protection considerations for outbound missions to small bodies in the solar system. More specifically, NASA asked CoPP to consider whether identifiable populations within the solar system are so numerous or of sufficiently low scientific interest as to merit relief from planetary protection requirements in order to simplify possible future exploration and commercial ventures. Given interest in developing a robust exploration program, as discussed in the Planetary Science and Astrobiology Decadal Survey 2022,³ and in the burgeoning private space sector, this is a timely issue to address.

To gather information and discuss the issues, the CoPP met five times in 2021 and 2022, virtually during the COVID-19 pandemic, on the following dates: November 30 to 2 December 2021; January 19, 2022; February 9, 2022; March 2, 2022; and March 21–24, 2022. A completed draft of this report was assembled in April 2022.

The committee would like to thank J. Nick Benardini (NASA), Athena Coustenis (COSPAR Panel on Planetary Protection), Lori Glaze (NASA), Stefanie Milam (Small Bodies Assessment Group), Harry McSween (University of Tennessee), Daniel Britt (University of Central Florida), Clark Chapman (Southwest Research Institute [SwRI]), David Trilling (Northern Arizona University), Lori Feaga (University of Maryland), Henry Hsieh (Planetary Science Institute), William Bottke (SwRI), Cathy Olkin (SwRI), Kelvin Coleman (Federal Aviation Administration [FAA]), Jeff Parker (Advanced Space), Joel Sercel (TransAstra), Robert Jedicke (University of Hawaii), Andy Rivkin (Johns Hopkins University), Brent Buffington (Jet Propulsion Laboratory-California Institute of Technology [JPL-Caltech]), Mark Wallace (JPL-Caltech), Jason Dworkin (NASA Goddard Space Flight Center), Alexandra

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¹ National Academies of Sciences, Engineering, and Medicine (NASEM), 2020, Assessment of the Report of NASA’s Planetary Protection Independent Review Board, Washington, DC: The National Academies Press, https://doi.org/10.17226/25773.

² NASEM, 2018, Review and Assessment of Planetary Protection Policy Development Processes, Washington, DC: The National Academies Press, https://doi.org/10.17226/25172, Recommendation 3.6.

³ NASEM, 2022, 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.

Pontefract (Georgetown University), Harrison Smith (Earth-Life Science Institute), Frank Groen (NASA), Steph Earle (FAA), Tom Hammond (U.S. House of Representatives Subcommittee on Space and Aeronautics), Ezinne Uzo-Okoro (Office of Science and Technology Policy), and Pamela Whitney (U.S. House of Representatives Subcommittee on Space and Aeronautics) for their presentations to CoPP.