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Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×

Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies

Framework for Decision Making

Task Group on Sample Return from Small Solar System Bodies

Space Studies Board

Commission on Physical Sciences, Mathematics, and Applications

National Research Council

NATIONAL ACADEMY PRESS
Washington, D.C. 1998

Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×

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 task group responsible for the report were chosen for their special competences and with regard for appropriate balance.

The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance 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. Bruce Alberts 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. William A. Wulf 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 purposes of furthering knowledge and advising the federal government. Functioning in accordance 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 engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Bruce Alberts and Dr. William A. Wulf are chairman and vice chairman, respectively, of the National Research Council.

This study was supported by Contract No. NASW-96013 between the National Academy of Sciences and the National Aeronautics and Space Administration. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the organizations or agencies that provided support for this project.

Library of Congress Catalog Card Number 98-85797

International Standard Book Number 0-309-06136-9

Cover design by Penny Margolskee. Comet photo courtesy of Dennis di Cicco. Asteroid and Europa images courtesy of NASA/JPL/Caltech.

Additional copies of this report are available from:
National Academy Press
2101 Constitution Ave., NW Box 285 Washington DC 20055 800-624-6242 202-334-3313 (in the Washington metropolitan area) http://www.nap.edu

Copyright © 1998 by the National Academy of Sciences. All rights reserved.

Printed in the United States of America

Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×

TASK GROUP ON SAMPLE RETURN FROM SMALL SOLAR SYSTEM BODIES

LESLIE ORGEL,

Salk Institute for Biological Studies,

Chair

MICHAEL A'HEARN,

University of Maryland

JEFFREY BADA,

University of California, San Diego

JOHN BAROSS,

University of Washington

CLARK CHAPMAN,

Southwest Research Institute

MICHAEL DRAKE,

University of Arizona

JOHN KERRIDGE,

University of California, San Diego

MARGARET S. RACE,

SETI Institute

MITCHELL SOGIN,

Marine Biological Laboratory, Woods Hole

STEVEN SQUYRES,

Cornell University

JOSEPH L. ZELIBOR, JR., Study Director

JACQUELINE ALLEN, Project Assistant

Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×

SPACE STUDIES BOARD

CLAUDE R. CANIZARES,

Massachusetts Institute of Technology,

Chair

MARK R. ABBOTT,

Oregon State University

DANIEL N. BAKER,

University of Colorado

LAWRENCE BOGORAD,

Harvard University

DONALD E. BROWNLEE,

University of Washington

GERARD W. ELVERUM, JR.,

TRW Space and Technology Group

ANTHONY W. ENGLAND,

University of Michigan

MARILYN L. FOGEL,

Carnegie Institution of Washington

RONALD GREELEY,

Arizona State University

BILL GREEN, former member,

U.S. House of Representatives

ANDREW H. KNOLL,

Harvard University

ROBERTA BALSTAD MILLER,

CIESIN

BERRIEN MOORE III,

University of New Hampshire

MARY JANE OSBORN,

University of Connecticut Health Center

SIMON OSTRACH,

Case Western Reserve University

MORTON B. PANISH,

AT&T Bell Laboratories (retired)

CARLÉ M. PIETERS,

Brown University

THOMAS A. PRINCE,

California Institute of Technology

PEDRO L. RUSTAN, JR.,

U.S. Air Force (retired)

JOHN A. SIMPSON,

Enrico Fermi Institute

GEORGE L. SISCOE,

Boston University

EDWARD M. STOLPER,

California Institute of Technology

RAYMOND VISKANTA,

Purdue University

ROBERT E. WILLIAMS,

Space Telescope Science Institute

MARC S. ALLEN, Director (through December 12, 1997)

JOSEPH K. ALEXANDER, Director (as of February 17, 1998)

Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×

COMMISSION ON PHYSICAL SCIENCES, MATHEMATICS, AND APPLICATIONS

ROBERT J. HERMANN,

United Technologies Corporation,

Co-chair

W. CARL LINEBERGER,

University of Colorado,

Co-chair

PETER M. BANKS,

ERIM International, Inc.

WILLIAM BROWDER,

Princeton University

LAWRENCE D. BROWN,

University of Pennsylvania

RONALD G. DOUGLAS,

Texas A&M University

JOHN E. ESTES,

University of California at Santa Barbara

MARTHA P. HAYNES,

Cornell University

L. LOUIS HEGEDUS,

Elf Atochem North America, Inc.

JOHN E. HOPCROFT,

Cornell University

CAROL M. JANTZEN,

Westinghouse Savannah River Company

PAUL G. KAMINSKI,

Technovation, Inc.

KENNETH H. KELLER,

University of Minnesota

KENNETH I. KELLERMANN,

National Radio Astronomy Observatory

MARGARET G. KIVELSON,

University of California at Los Angeles

DANIEL KLEPPNER,

Massachusetts Institute of Technology

JOHN KREICK,

Sanders, a Lockheed Martin Company

MARSHA I. LESTER,

University of Pennsylvania

NICHOLAS P. SAMIOS,

Brookhaven National Laboratory

CHANG-LIN TIEN,

University of California at Berkeley

NORMAN METZGER, Executive Director

Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
This page in the original is blank.
Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×

Foreword

For the first time since the Apollo program, NASA has specific plans to bring samples to Earth from elsewhere in the solar system. The earliest mission, Stardust, is scheduled to be launched in 1999 and return approximately 7 years later with a collection of cometary and interplanetary material. Other missions in various stages of definition would gather bits from Mars, an asteroid, or the satellites of Jupiter.

Prudence demands giving proper attention to handling extraterrestrial samples so that they pose no risk to Earth's biosphere. At the same time, an unreasonable level of concern could needlessly escalate the cost of sample handling or obviate such missions altogether.

Since Mars is the place most often considered as a possible host of past or present microbial life forms and one from which samples will surely be returned within the next decade, it has received the greatest amount of attention, including a recent study by a task group of the Space Studies Board (National Research Council, 1997, Mars Sample Return: Issues and Recommendations, National Academy Press, Washington D.C.). The present report broadens the scope of consideration to encompass the other bodies in the solar system.

The report finds that the degree of caution required in handling material depends on its site of origin. To a high degree of confidence, some returned samples do not need special handling precautions. Others might be in this category, but the degree of confidence is lower. For still others, the samples should be handled with the same degree of containment as would be applied to material from Mars.

In addition, the report considers further research that would inform this issue and reduce areas of uncertainty. Learning how some of Earth's hardier microbes would fare under the extreme conditions of radiation and temperature can help increase our understanding of the sterilization processes that occur naturally in parts of the solar system.

Since NASA has plans to bring Mars rocks back to Earth within a decade, the proper procedures for handling the most suspect samples must be put in place. This report shows that the full machinery of containment will also be required for some material, but certainly not everything, collected in our neighborhood.

Claude R. Canizares, Chair

Space Studies Board

Page viii Cite
Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
This page in the original is blank.
Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×

Preface

The National Research Council's Space Studies Board provides guidance to NASA on planetary protection, which is the effort to preserve conditions for future biological and organic exploration on planets and other solar system objects and to protect Earth and its biosphere from potential extraterrestrial sources of contamination. In 1997, the Space Studies Board produced the report Mars Sample Return: Issues and Recommendations, which assessed the potential for a viable exogenous biological entity to be included in a sample returned to Earth from Mars as well as the potential for large-scale effects if such an entity were inadvertently introduced into Earth's biosphere. The report provides justification for and recommendations on procedures for the quarantine of samples returned from Mars.

Given the prospect of sample return missions from various small solar system bodies in the next decade, NASA then requested that the Board assess the potential for a living entity to be present in or on samples returned from small solar system bodies such as planetary satellites, asteroids, and comets. Guidance from the new study would extend and generalize to other solar system bodies the published advice regarding Mars.

In response to NASA's request, the Space Studies Board convened the Task Group on Sample Return from Small Solar System Bodies to assess the potential for a living entity to be present in or on samples returned from small solar system bodies by addressing the following:

  • The potential for a living entity to be contained in or on samples returned from planetary satellites or small solar system bodies, such as asteroids, comets, and meteoroids;

  • Detectable differences among small solar system bodies that would affect the above assessment;

  • Scientific investigations that need to be conducted to reduce the uncertainty in the above assessment; and

  • The potential risk posed by samples returned directly to Earth from spaceflight missions, as compared to the natural influx of material that enters Earth's atmosphere as interplanetary dust particles, meteorites, and other small impactors.

The task group met three times over an 11-month period, reviewed relevant reports, was briefed by representatives from NASA and expert researchers and practitioners on topics related to sample return, and held a workshop to obtain a wide spectrum of perspectives. The task group considered in some detail the following topics:

  1. The possibility that, at some time in the past, life originated on a body from which a sample might be taken, or that life was transported there from elsewhere in the solar system;

Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
  1. The possibility that life still exists on the body either in active or in reactivatable form; and

  2. The potential hazard to terrestrial ecosystems from extraterrestrial life if it exists in a returned sample.

The central concern addressed by the task group in this report is the possibility that samples returned to Earth from small solar bodies might harbor living entities that could harm terrestrial living organisms or disrupt their ecosystems. The primary audience for the task group's report is NASA, those who have a stake in sample return missions and planetary protection, and the public at large.

The task group members wish to thank those individuals who made presentations at the task group meetings, including Sherwood Chang, NASA-Ames; Christopher Chyba, University of Arizona; Ben Clark, Lockheed-Martin; John Cronin, Arizona State University; James Ferris, Rensselaer Polytechnic Institute; Marina Fomenkova, University of California, San Diego; Ted Roush, San Francisco State University; and Perry Stabekis, Lockheed-Martin. Special thanks are given to John Rummel and Michael Meyer for serving as the project's points of contact at NASA and for their presentations to the task group.

Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×

Acknowledgment of Reviewers

This report has been reviewed by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the National Research Council's (NRC's) Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the authors and the NRC in making the published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The content of the review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their participation in the review of this report:

Rita R. Colwell, University of Maryland;

Ellis Cowling, North Carolina State University;

Michael Gaffey, Rensselaer Polytechnic Institute;

Donald M. Hunten, University of Arizona;

Marsha I. Lester, University of Pennsylvania;

Harry Y. McSween, Jr., University of Tennessee;

Norman R. Pace, University of California, Berkeley;

Everett L. Shock, Washington University; and

John A. Wood, Harvard University.

Although the individuals listed above provided many constructive comments and suggestions, responsibility for the final content of this report rests solely with the authoring task group and the NRC.

Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
This page in the original is blank.
Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
   

Potential for a Living Entity to Be in or on Samples Returned from Planetary Satellites

 

35

   

Scientific Investigations to Reduce the Uncertainty in the Assessment of Planetary Satellites

 

36

   

Phobos and Deimos

 

36

   

Europa

 

36

   

Ganymede

 

37

   

Callisto

 

37

   

Summary

 

37

   

References

 

37

4

 

ASTEROIDS AND METEORITES

 

40

   

Undifferentiated, Primitive (C-Type) Asteroids

 

43

   

Undifferentiated, Metamorphosed Asteroids

 

45

   

Differentiated Asteroids

 

46

   

Potential for a Living Entity to Be in or on Samples Returned from Asteroids

 

47

   

Scientific Investigations to Reduce the Uncertainty in the Assessment of Asteroids

 

49

   

Summary

 

50

   

References

 

50

5

 

COMETS

 

52

   

Origin

 

52

   

Place of Formation

 

52

   

Nebular Processes and Accretion

 

52

   

Gravitational Scattering

 

53

   

Early Heating and Melting

 

54

   

Composition

 

55

   

Physical Characteristics

 

55

   

Chemical Composition

 

56

   

Past and Present Environmental Conditions

 

58

   

Delivery of Samples to Earth

 

59

   

Potential for a Living Entity to Be in or on Samples Returned from Comets

 

60

   

Scientific Investigations to Reduce the Uncertainty in the Assessment of Comets

 

62

   

Summary

 

62

   

References

 

63

6

 

COSMIC DUST

 

64

   

Natural Infall of Dust to Earth

 

65

   

Potential for a Living Entity to Be in or on Returned Samples of Cosmic Dust

 

66

   

Scientific Investigations to Reduce the Uncertainty in the Assessment of Cosmic Dust

 

66

   

Summary

 

67

   

References

 

67

7

 

CONSIDERING THE POTENTIAL RISKS FROM RETURNED SAMPLES

 

69

   

Likelihood of Finding and Including a Living Organism in Samples from Different Solar System Bodies

 

70

   

Anticipating the Putative Nature of Life from Small Solar System Bodies

 

71

   

Concerns About Potential Biohazards and Adverse Effects

 

71

Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
This page in the original is blank.
Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
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Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
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Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
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Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
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Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
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Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
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Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
Page R7
Page viii Cite
Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
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Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
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Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
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Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
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Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
Page R12
Page xiii Cite
Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
Page R13
Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
Page R14
Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
Page R15
Suggested Citation:"Front Matter." National Research Council. 1998. Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making. Washington, DC: The National Academies Press. doi: 10.17226/6281.
×
Page R16
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For the first time since the Apollo program, NASA and space agencies abroad have plans to bring samples to Earth from elsewhere in the solar system. There are missions in various stages of definition to gather material over the next decade from Mars, an asteroid, comets, the satellites of Jupiter, and the interplanetary dust. Some of these targets, most especially Jupiter's satellites Europa and Ganymede, now appear to have the potential for harboring living organisms.

This book considers the possibility that life may have originated or existed on a body from which a sample might be taken and the possibility that life still exists on the body either in active form or in a form that could be reactivated. It also addresses the potential hazard to terrestrial ecosystems from extraterrestrial life if it exists in a returned sample. Released at the time of the Internationl Committee on Space Research General Assembly, the book has already established the basis for plans for small body sample retruns in the international space research community.

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