Radiation and the International Space Station : recommendations to reduce risk

EXECUTIVE SUMMARY 1 1 SCOPING THE PROBLEM7 1.1 Radiation in Space, 7 1.2 Space Weather Context, 10 1.3 Metrics of Radiation Risk, 11 1.4 Radiation and the International Space Station, 12 1.5 Issues in Managing Radiation Risk During ISS Construction, 18 1.6 The Apollo Experience, 19 1.7 Summary and Recommendation, 20 1.8 Notes and References, 21 2 SOLAR PARTICLE EVENTS AND THE INTERNATIONAL SPACE STATION24 2.1 Background to an Assessment of SPE Impacts on ISS Construction, 24 2.2 Probability of SPE Impact on ISS Construction, 25 2.3 Correlation Between SPEs and Size of the SPE Zone, 27 2.4 Summary and Recommendation, 30 2.5 Notes and References, 30 3 RELATIVISTIC ELECTRONS AND THE INTERNATIONAL SPACE STATION32 3.1 Outer Belt Electrons, 32 3.2 Monitoring Outer Belt Electrons, 33 3.3 Predictability of Radiation Belt Electrons at Low Altitude, 34 3.4 Assessment of Hazards Faced by Astronauts During ISS Construction, 35 3.5 Operational Strategy, 36 3.6 Summary and Recommendations, 37 3.7 Notes and References, 38 Copyright © National Academy of Sciences. All rights reserved. Radiation and the International Space Station: Recommendations to Reduce Risk http://www.nap.edu/catalog/9725.html xvi CONTENTS 4 SPACECRAFT SOURCES OF OPERATIONAL RADIATION DATA39 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 CONNECTIONS45 5.1 Institutional Factors Limiting Interagency Ability to Provide Better Information for Operational Radiation Risk Assessments, 45 5.2 Recommendations, 47 6 INTRA-NASA CONNECTIONS48 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 REDUCTION59 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 MEMBERS70 D ACRONYMS AND ABBREVIATIONS74