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Suggested Citation:"Front Matter." National Research Council. 2000. Radiation and the International Space Station: Recommendations to Reduce Risk. Washington, DC: The National Academies Press. doi: 10.17226/9725.
×

Radiation and the International Space Station

Recommendations to Reduce Risk

Committee on Solar and Space Physics

Committee on Solar-Terrestrial Research

Space Studies Board

Board on Atmospheric Sciences and Climate

Commission on Physical Sciences, Mathematics, and Applications

Commission on Geosciences, Environment, and Resources

National Research Council

NATIONAL ACADEMY PRESS
Washington, D.C.

Suggested Citation:"Front Matter." National Research Council. 2000. Radiation and the International Space Station: Recommendations to Reduce Risk. Washington, DC: The National Academies Press. doi: 10.17226/9725.
×

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

Support for this project was provided by Contract NASW 96013 between the National Academy of Sciences and the National Aeronautics and Space Administration. Any opinions, findings, conclusions, or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the sponsor.

Cover: Ground track of ISS orbits superposed on a globe along with polar cap areas (shown in yellow), where multimega-electron volt solar energetic particles penetrated to low altitudes during an SPE in November 1997. (Image courtesy of R.A. Leske, R.A. Mewaldt, E.C. Stone, and T.T. von Rosenvinge, “Geomagnetic Cutoff Variations During Solar Energetic Particle Events—Implications for the Space Station,” Proceedings of the 25th International Cosmic Ray Conference, 2, Space Research Unit, Department of Physics, Potchefstroom University for Christian Higher Education, South Africa, 1997, p. 381.)

International Standard Book Number 0-309-06885-1

Copies of this report are available free of charge from:

Space Studies Board

National Research Council

2101 Constitution Avenue, NW

Washington, DC 20418

Copyright 2000 by the National Academy of Sciences. All rights reserved.

Printed in the United States of America

Suggested Citation:"Front Matter." National Research Council. 2000. Radiation and the International Space Station: Recommendations to Reduce Risk. Washington, DC: The National Academies Press. doi: 10.17226/9725.
×

THE NATIONAL ACADEMIES

National Academy of Sciences

National Academy of Engineering

Institute of Medicine

National Research Council

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 M. 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 M. Alberts and Dr. William A. Wulf are chairman and vice chairman, respectively, of the National Research Council.

Suggested Citation:"Front Matter." National Research Council. 2000. Radiation and the International Space Station: Recommendations to Reduce Risk. Washington, DC: The National Academies Press. doi: 10.17226/9725.
×

COMMITTEE ON SOLAR AND SPACE PHYSICS

GEORGE L. SISCOE,

Boston University,

Chair

CHARLES W. CARLSON,

University of California, Berkeley

ROBERT L. CAROVILLANO,

Boston College

TAMAS I. GOMBOSI,

University of Michigan

RAYMOND A. GREENWALD,

Applied Physics Laboratory

JUDITH T. KARPEN,

Naval Research Laboratory

GLENN M. MASON,

University of Maryland

MARGARET A. SHEA,

Air Force Research Laboratory

KEITH T. STRONG,

Lockheed Palo Alto Research Center

RICHARD A. WOLF,

Rice University

ARTHUR CHARO, Senior Program Officer

RONALD TURNER, Consultant

CARMELA J. CHAMBERLAIN, Senior Project Assistant (through March 1999)

THERESA M. FISHER, Senior Project Assistant (from April 1999)

Suggested Citation:"Front Matter." National Research Council. 2000. Radiation and the International Space Station: Recommendations to Reduce Risk. Washington, DC: The National Academies Press. doi: 10.17226/9725.
×

COMMITTEE ON SOLAR-TERRESTRIAL RESEARCH

MICHAEL C. KELLEY,

Cornell University,

Chair

MAURA E. HAGEN,

National Center for Atmospheric Research

MARY K. HUDSON,

Dartmouth College

NORMAN F. NESS,

Bartol Research Institute

THOMAS F. TASCIONE,

Sterling Software

ELBERT (JOE) FRIDAY, JR., Director,

Board on Atmospheric Sciences and Climate

TENECIA A. BROWN, Senior Project Assistant

Suggested Citation:"Front Matter." National Research Council. 2000. Radiation and the International Space Station: Recommendations to Reduce Risk. Washington, DC: The National Academies Press. doi: 10.17226/9725.
×

SPACE STUDIES BOARD

CLAUDE R. CANIZARES,

Massachusetts Institute of Technology,

Chair

MARK R. ABBOTT,

Oregon State University

FRAN BAGENAL,

University of Colorado

DANIEL N. BAKER,

University of Colorado

ROBERT E. CLELAND,

University of Washington

GERARD W. ELVERUM, JR.,

TRW Space and Technology Group*

MARILYN L. FOGEL,

Carnegie Institution of Washington

BILL GREEN,

Former Member, U.S. House of Representatives

JOHN H. HOPPS, JR.,

Morehouse College

CHRIS J. JOHANNSEN,

Purdue University

ANDREW H. KNOLL,

Harvard University*

RICHARD G. KRON,

University of Chicago

JONATHAN I. LUNINE,

University of Arizona

ROBERTA BALSTAD MILLER,

CIESIN-Columbia University

GARY J. OLSEN,

University of Illinois, Urbana-Champaign

MARY JANE OSBORN,

University of Connecticut Health Center

GEORGE A. PAULIKAS,

The Aerospace Corporation

JOYCE E. PENNER,

University of Michigan

THOMAS A. PRINCE,

California Institute of Technology

PEDRO L. RUSTAN, JR.,

Ellipso, Inc.

GEORGE L. SISCOE,

Boston University

EUGENE B. SKOLNIKOFF,

Massachusetts Institute of Technology

MITCHELL SOGIN,

Marine Biological Laboratory

NORMAN E. THAGARD,

Florida State University

ALAN M. TITLE,

Lockheed Martin Advanced Technology Center

RAYMOND VISKANTA,

Purdue University

PETER VOORHEES,

Northwestern University

JOHN A. WOOD,

Harvard-Smithsonian Center for Astrophysics

JOSEPH K. ALEXANDER, Director

*  

 Former member.

Suggested Citation:"Front Matter." National Research Council. 2000. Radiation and the International Space Station: Recommendations to Reduce Risk. Washington, DC: The National Academies Press. doi: 10.17226/9725.
×

BOARD ON ATMOSPHERIC SCIENCES AND CLIMATE

ERIC J. BARRON,

Pennsylvania State University,

Co-chair

JAMES R. MAHONEY,

International Technology Corporation,

Co-chair

SUSAN K. AVERY,

University of Colorado

LANCE F. BOSART,

State University of New York at Albany

MARVIN A. GELLER,

State University of New York at Stony Brook

DONALD M. HUNTEN,

University of Arizona*

JOHN IMBRIE,

International Technology Corporation*

CHARLES E. KOLB,

Aerodyne Research, Inc.

THOMAS J. LENNON, Brig. Gen. USAF (ret.),

WSI Corp.*

ROGER A. PIELKE, JR.,

National Center for Atmospheric Research

ROBERT T. RYAN,

WRC-TV

MARK R. SCHOEBERL,

NASA Goddard Space Flight Center

JOANNE SIMPSON,

NASA Goddard Space Flight Center

NIEN DAK SZE,

Atmospheric and Environmental Research, Inc.

ROBERT WELLER,

Woods Hole Oceanographic Institution

ERIC F. WOOD,

Princeton University

ELBERT (JOE) FRIDAY, JR., Director

*  

 Former member.

Page viii Cite
Suggested Citation:"Front Matter." National Research Council. 2000. Radiation and the International Space Station: Recommendations to Reduce Risk. Washington, DC: The National Academies Press. doi: 10.17226/9725.
×

COMMISSION ON PHYSICAL SCIENCES, MATHEMATICS, AND APPLICATIONS

PETER M. BANKS,

Veridian ERIM International, Inc.,

Co-chair

W. CARL LINEBERGER,

University of Colorado,

Co-chair

WILLIAM F. BALLHAUS, JR.,

Lockheed Martin Corp.

SHIRLEY CHIANG,

University of California at Davis

MARSHALL H. COHEN,

California Institute of Technology

RONALD G. DOUGLAS,

Texas A&M University

SAMUEL H. FULLER,

Analog Devices, Inc.

JERRY P. GOLLUB,

Haverford College

MICHAEL F. GOODCHILD,

University of California at Santa Barbara

MARTHA P. HAYNES,

Cornell University

WESLEY T. HUNTRESS, JR.,

Carnegie Institution

CAROL M. JANTZEN,

Westinghouse Savannah River Company

PAUL G. KAMINSKI,

Technovation, Inc.

KENNETH H. KELLER,

University of Minnesota

JOHN R. KREICK,

Sanders, a Lockheed Martin Company (ret.)

MARSHA I. LESTER,

University of Pennsylvania

DUSA M. McDUFF,

State University of New York at Stony Brook

JANET L. NORWOOD, U.S. Commissioner of Labor Statistics (ret.)

M. ELISABETH PATÉ-CORNELL,

Stanford University

NICHOLAS P. SAMIOS,

Brookhaven National Laboratory

ROBERT J. SPINRAD,

Xerox PARC (ret.)

NORMAN METZGER, Executive Director (through July 1999)

MYRON F. UMAN, Acting Executive Director (from August 1999)

Suggested Citation:"Front Matter." National Research Council. 2000. Radiation and the International Space Station: Recommendations to Reduce Risk. Washington, DC: The National Academies Press. doi: 10.17226/9725.
×

COMMISSION ON GEOSCIENCES, ENVIRONMENT, AND RESOURCES

GEORGE M. HORNBERGER,

University of Virginia,

Chair

RICHARD A. CONWAY,

Union Carbide Corporation (ret.)

THOMAS E. GRAEDEL,

Yale University

THOMAS J. GRAFF,

Environmental Defense Fund

EUGENIA KALNAY,

University of Maryland

DEBRA KNOPMAN,

Progressive Policy Institute

KAI N. LEE,

Williams College

RICHARD A. MESERVE,

Covington & Burling

RADM. JOHN B. MOONEY, JR., USN (ret.),

J. Brad Mooney Associates, Ltd.

HUGH C. MORRIS,

El Dorado Gold Corporation, Vancouver, British Columbia

H. RONALD PULLIAM,

University of Georgia

MILTON RUSSELL,

University of Tennessee

THOMAS C. SCHELLING,

University of Maryland

ANDREW R. SOLOW,

Woods Hole Oceanographic Institution

VICTORIA J. TSCHINKEL,

Landers and Parsons

E-AN ZEN,

University of Maryland

MARY LOU ZOBACK,

U.S. Geological Survey

ROBERT M. HAMILTON, Executive Director

Suggested Citation:"Front Matter." National Research Council. 2000. Radiation and the International Space Station: Recommendations to Reduce Risk. Washington, DC: The National Academies Press. doi: 10.17226/9725.
×
This page in the original is blank.
Suggested Citation:"Front Matter." National Research Council. 2000. Radiation and the International Space Station: Recommendations to Reduce Risk. Washington, DC: The National Academies Press. doi: 10.17226/9725.
×

Foreword

A major objective of the International Space Station is learning how to cope with the inherent risks of human spaceflight—how to live and work in space for extended periods. The construction of the station itself provides the first opportunity for doing so.

Prominent among the challenges associated with ISS construction is the large amount of time that astronauts will be spending doing extravehicular activity (EVA), or ''space walks." EVAs from the space shuttle have been extraordinarily successful, most notably the on-orbit repair of the Hubble Space Telescope. But the number of hours of EVA for ISS construction exceeds that of the Hubble repair mission by orders of magnitude. Furthermore, the ISS orbit has nearly twice the inclination to Earth's equator as Hubble's orbit, so it spends part of every 90-minute circumnavigation at high latitudes, where Earth's magnetic field is less effective at shielding impinging radiation. This means that astronauts sweeping through these regions will be considerably more vulnerable to dangerous doses of energetic particles from a sudden solar eruption.

This putative radiation danger prompted the present study. It applies what we have learned from past investigations of solar emanations and their effects on Earth's magnetosphere to assess the risk and find ways to minimize it. The study estimates that the likelihood of having a potentially dangerous solar event during an EVA is indeed very high. It also recommends steps that can be taken immediately, and over the next several years, to provide adequate warning so that the astronauts can be directed to take protective cover inside the ISS or shuttle. The near-term actions include programmatic and operational ways to take advantage of the multiagency assets that currently monitor and forecast space weather, and ways to improve the in situ measurements and the predictive power of current models.

The radiation risk is real, but it is also very susceptible to management. That there have been no known overexposures to date is due partly to such good management. Now it is time to revise the protocols and practices of the past to encompass the new challenges of ISS construction and permanent habitation to ensure that this good record continues in the future.

Claude R. Canizares, Chair

Space Studies Board

Suggested Citation:"Front Matter." National Research Council. 2000. Radiation and the International Space Station: Recommendations to Reduce Risk. Washington, DC: The National Academies Press. doi: 10.17226/9725.
×
This page in the original is blank.
Page xiii Cite
Suggested Citation:"Front Matter." National Research Council. 2000. Radiation and the International Space Station: Recommendations to Reduce Risk. Washington, DC: The National Academies Press. doi: 10.17226/9725.
×

Acknowledgments

Preparing this report would not have been possible without the help of the many individuals who provided the Committee on Solar and Space Physics and the Committee on Solar-Terrestrial Research (CSSP/CSTR) with presentations, consultations, and written materials. The committees are especially grateful to the following individuals: for information on the probability of a solar particle event (SPE) coinciding with an International Space Station (ISS) construction mission, Ronald Turner (ANSER Corporation); for information on the properties of penetrating radiation and on the latitudinal cutoff of SPE particles, Don Smart (Air Force Research Laboratory, ret.); for information on the properties and measurements of highly relativistic electrons in the outer radiation belt, Herbert Kroehl (NOAA's National Geophysics Data Center) and Bernard Blake (Aerospace Corporation); for information pertaining to NOAA's Space Environment Center (SEC), Gary Heckman (NOAA-SEC); for information on matters pertaining to mission operations at Johnson Space Center (JSC) and on radiation data taken on Mir and the shuttles, Michael Golightly and Gautam Badhwar (both at JSC); and for information pertaining to radiation risk management during the Apollo era (the SPAN program), Donald Robbins, Alva Hardy, and Rod Rose (all at JSC during the Apollo era).

In addition, CSSP/CSTR wishes to acknowledge the following individuals for informative presentations and interviews at its meetings: for a flight director's perspective, Paul Hill (JSC); for a flight surgeon's perspective, Jeff Jones (JSC); for an astronaut's perspective, Norman Thagard (Florida State University); for information on radiation effects on biological materials and organisms and on research programs pertaining to these, Walter Schimmerling (NASA headquarters), Richard Setlow (Brookhaven National Laboratory), R.J. Michael Fry (Oak Ridge National Laboratory), and Larry Townsend (University of Tennessee); and for information on radiation effects on other than biological materials and on NASA's Space Environment Effects program at Marshall Space Flight Center, Dana Brewer (NASA headquarters) and Janet Barth (Goddard Space Flight Center). The report has also benefited from inputs by members of the National Research Council's Committee on Space Biology and Medicine, which is chaired by Mary J. Osborn; from the Space Studies Board, especially Fran Bagenal; and from Margaret Kivelson, liaison from the Commission on Physical Sciences, Mathematics and Applications to the Space Studies Board.

This report has been reviewed by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the Report Review Committee of the National Research Council (NRC). 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

Suggested Citation:"Front Matter." National Research Council. 2000. Radiation and the International Space Station: Recommendations to Reduce Risk. Washington, DC: The National Academies Press. doi: 10.17226/9725.
×

standards for objectivity, evidence, and responsiveness to the study charge. The contents of the review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. CSSP/CSTR wishes to thank the following individuals for their participation in the review of this report: J. Bernard Blake, the Aerospace Corporation; Joan Feynman, Jet Propulsion Laboratory; R.J. Michael Fry, Oak Ridge National Laboratory; John Grunsfeld, NASA Johnson Space Center; Louis J. Lanzerotti, Lucent Technologies; Edward T. Lu, NASA Johnson Space Center; Frank B. McDonald, University of Maryland; and Donald J. Williams, Johns Hopkins University Applied Physics Laboratory.

Although the individuals listed above have provided many constructive comments and suggestions, responsibility for the final content of this report rests solely with CSSP/CSTR and the NRC.

Suggested Citation:"Front Matter." National Research Council. 2000. Radiation and the International Space Station: Recommendations to Reduce Risk. Washington, DC: The National Academies Press. doi: 10.17226/9725.
×

4

 

SPACECRAFT SOURCES OF OPERATIONAL RADIATION DATA

 

39

   

4.1 Value of Spacecraft Monitors in Support of ISS Construction

 

39

   

4.2 An Interagency Fleet of Spacecraft Monitors

 

41

   

4.3 Future Spacecraft in Support of ISS Operations

 

42

   

4.4 Summary and Recommendation

 

44

   

4.5 Notes and References

 

44

5

 

INTERAGENCY CONNECTIONS

 

45

   

5.1 Institutional Factors Limiting Interagency Ability to Provide Better Information for Operational Radiation Risk Assessments

 

45

   

5.2 Recommendations

 

47

6

 

INTRA-NASA CONNECTIONS

 

48

   

6.1 Radiation: A Concern throughout NASA

 

48

   

6.2 NASA Programs That Involve Radiation

 

49

   

6.3 Communication between Programs with an Interest in Radiation

 

50

   

6.4 Summary and Recommendation

 

51

 

 

EPILOGUE: A NOTIONAL SCENARIO FOR IMPROVED SUPPORT OF INTERNATIONAL SPACE STATION CONSTRUCTION

 

52

   

E.1 Vision of an ISS Construction Mission Supported by Reliable, Accurate Radiation Forecast Models during the Solar Maximum

 

52

   

E.2 The Way Things Ought to Work

 

52

   

E.3 The Missing Pieces

 

55

   

E.4 Timetable for Implementing the Report's Recommendations

 

55

 

 

APPENDIXES

 

 

   

A SPACE WEATHER MODELS APPLIED TO RADIATION RISK REDUCTION

 

59

   

A.1 Space Weather Models

 

59

   

A.2 Near-Earth Space Environment Models

 

61

   

A.3 Advanced Empirically Based Forecast Models of Radiation Risk Parameters

 

62

   

A.4 Observational Supplements to Model-Based Forecasts

 

62

   

A.5 National Space Weather Program

 

63

   

A.6 Summary and Findings

 

64

   

A.7 Notes and References

 

66

   

B STATEMENT OF TASK

 

68

   

C BIOGRAPHIES OF COMMITTEE MEMBERS

 

70

   

D ACRONYMS AND ABBREVIATIONS

 

74

Suggested Citation:"Front Matter." National Research Council. 2000. Radiation and the International Space Station: Recommendations to Reduce Risk. Washington, DC: The National Academies Press. doi: 10.17226/9725.
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A major objective of the International Space Station is learning how to cope with the inherent risks of human spaceflight—how to live and work in space for extended periods. The construction of the station itself provides the first opportunity for doing so. Prominent among the challenges associated with ISS construction is the large amount of time that astronauts will be spending doing extravehicular activity (EVA), or "space walks." EVAs from the space shuttle have been extraordinarily successful, most notably the on-orbit repair of the Hubble Space Telescope. But the number of hours of EVA for ISS construction exceeds that of the Hubble repair mission by orders of magnitude. Furthermore, the ISS orbit has nearly twice the inclination to Earth's equator as Hubble's orbit, so it spends part of every 90-minute circumnavigation at high latitudes, where Earth's magnetic field is less effective at shielding impinging radiation. This means that astronauts sweeping through these regions will be considerably more vulnerable to dangerous doses of energetic particles from a sudden solar eruption.

Radiation and the International Space Station estimates that the likelihood of having a potentially dangerous solar event during an EVA is indeed very high. This report recommends steps that can be taken immediately, and over the next several years, to provide adequate warning so that the astronauts can be directed to take protective cover inside the ISS or shuttle. The near-term actions include programmatic and operational ways to take advantage of the multiagency assets that currently monitor and forecast space weather, and ways to improve the in situ measurements and the predictive power of current models.

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