HLS-UG-001 BASELINE RELEASE National Aeronautics and EFFECTIVE DATE: JANUARY 04, 2021 Space Administration HUMAN LANDING SYSTEM LUNAR THERMAL ANALYSIS GUIDEBOOK Publicly Available: Release to Public Websites Requires Approval of Chief, Office of Primary Responsibility, and approval via the Scientific and Technical Information (STI) process, if applicable The electronic version is the official approved document. Verify this is the correct version before use. Human Landing System Lunar Thermal Analysis Guidebook January 2021 Revision: Baseline Release Document No: HLS-UG-01 Effective Date: January 04, 2021 Page: 1 of 147 Title: Human Landing System Lunar Thermal Analysis Guidebook REVISION AND HISTORY PAGE Revision Change Effective Description No. No. Date - HLS- Baseline Release (Reference HCB.07.01.2020) 01/04/2021 C0064 The electronic version is the official approved document. Verify this is the correct version before use. Human Landing System Lunar Thermal Analysis Guidebook January 2021 Revision: Baseline Release Document No: HLS-UG-01 Effective Date: January 04, 2021 Page: 2 of 147 Title: Human Landing System Lunar Thermal Analysis Guidebook TABLE OF CONTENTS SECTION PAGE 1.0 INTRODUCTION ................................................................................................. 10 PURPOSE ........................................................................................................... 10 SCOPE ................................................................................................................ 10 CHANGE AUTHORITY/RESPONSIBILITY .......................................................... 10 2.0 DOCUMENTS ..................................................................................................... 10 APPLICABLE DOCUMENTS ............................................................................... 10 3.0 THE EARTH’S MOON ......................................................................................... 11 PHYSICAL CHARACTERISTICS ........................................................................ 12 ORBIT ................................................................................................................. 13 4.0 LUNAR SPACE THERMAL ENVIRONMENTS .................................................... 16 SOLAR CONSTANT ............................................................................................ 16 ALBEDO .............................................................................................................. 16 LUNAR LONG-WAVE RADIANCE ...................................................................... 16 Analytical Expressions .......................................................................... 16 Latitude/Longitude Tables of Lunar Surface Flux and/or Temperature .. 18 SOLAR ECLIPSE DURATIONS .......................................................................... 20 Low Lunar Orbit .................................................................................... 20 Near-Rectilinear Halo Orbit ................................................................... 21 5.0 LUNAR SURFACE THERMAL ENVIRONMENTS ............................................... 21 SURFACE FEATURES ....................................................................................... 21 Crater Size Distribution/Topography ..................................................... 22 Boulders/Rocks ..................................................................................... 22 LRO Diviner Digital Surface Data .......................................................... 23 SURFACE TEMPERATURE ............................................................................... 23 LRO Diviner Digital Temperature Data Maps ........................................ 23 Analytical Expressions (Steady State Approximation) ........................... 25 SUBSURFACE TEMPERATURE ........................................................................ 26 Apollo and Derived LRO Measurements ............................................... 27 GROUND HEAT FLOW ....................................................................................... 28 6.0 THERMO-PHYSICAL PROPERTIES OF LUNAR REGOLITH ............................. 29 The electronic version is the official approved document. Verify this is the correct version before use. Human Landing System Lunar Thermal Analysis Guidebook January 2021 Revision: Baseline Release Document No: HLS-UG-01 Effective Date: January 04, 2021 Page: 3 of 147 Title: Human Landing System Lunar Thermal Analysis Guidebook BULK THERMAL CONDUCTIVITY...................................................................... 29 SPECIFIC HEAT ................................................................................................. 32 BULK DENSITY................................................................................................... 32 THERMAL DIFFUSIVITY ..................................................................................... 33 7.0 OPTICAL PROPERTIES OF LUNAR REGOLITH ............................................... 36 SOLAR ABSORPTIVITY/ALBEDO ...................................................................... 37 INFRARED EMITTANCE ..................................................................................... 43 LIGHT SCATTER/SPECULARITY OF LUNAR REGOLITH ................................. 43 8.0 LUNAR ORBIT MODELING GUIDELINES/APPROACHES ................................. 44 NEAR RECTILINEAR HALO ORBIT (NRHO) ...................................................... 44 Description ............................................................................................ 44 Modeling Approach ............................................................................... 45 LOW LUNAR ORBIT (LLO) ................................................................................. 47 Description ............................................................................................ 47 Modeling Approach ............................................................................... 47 DESCENT/ASCENT ............................................................................................ 48 Description ............................................................................................ 48 Modeling Approach ............................................................................... 48 9.0 LUNAR SURFACE MODELING GUIDELINES/APPROACHES ........................... 55 MODELING THE GROUND-PLANE SOLAR ENVIRONMENT ............................ 56 Traditional Orbit Definition .................................................................... 58 Orbit Vector List .................................................................................... 59 Solar Elevation Angle............................................................................ 64 SUBSURFACE MODELING ................................................................................ 68 Approach .............................................................................................. 68 Boundary Conditions............................................................................. 69 Discretization ........................................................................................ 70 Initial Conditions Cyclic Steady State .................................................... 70 SELECTING TERRAIN SIZE ............................................................................... 74 Sizing Ground Plane ............................................................................. 74 Shadowing by Terrain Features ............................................................ 85 SIMPLIFIED TERRAIN MODELING .................................................................... 88 Far Field Boundary Conditions and Lunar Curvature ............................ 88 The electronic version is the official approved document. Verify this is the correct version before use. Human Landing System Lunar Thermal Analysis Guidebook January 2021 Revision: Baseline Release Document No: HLS-UG-01 Effective Date: January 04, 2021 Page: 4 of 147 Title: Human Landing System Lunar Thermal Analysis Guidebook Simplified Flat Plane Comparison to DSNE .......................................... 89 Far Field Terrain Modeling .................................................................... 93 DETAILED TERRAIN MODELING ...................................................................... 95 Accessing, importing and utilizing LRO digital Lunar Surface Data ....... 95 MODELING EXAMPLE...................................................................................... 104 Comparison to LRO Diviner Temperature Data ................................... 104 10.0 ACCOUNTING FOR LUNAR DUST IMPACTS .................................................. 105 11.0 SPECIAL CONSIDERATIONS FOR PSRS ....................................................... 109 EARTH SHINE .................................................................................................. 109 LUNAR SURFACE TEMPERATURE FOR COLD CASE ANALYSIS ................. 112 12.0 REFERENCES .................................................................................................. 112 APPENDIX A ACRONYMS AND ABBREVIATIONS AND GLOSSARY OF TERMS ........... 118 APPENDIX B OPEN WORK ................................................................................................ 122 APPENDIX C EXAMPLE MODELS/CASE STUDIES ........................................................... 123 APPENDIX D DERIVATIONS .............................................................................................