Human Exploration of Mars Design Reference Architecture 5.0 Addendum

406 Pages·2009·32.47 MB·English

NASA/SP–2009–566-ADD

Human Exploration of Mars
Design Reference Architecture 5.0

Addendum

Mars Architecture Steering Group
NASA Headquarters

Bret G. Drake, editor
NASA Johnson Space Center, Houston, Texas

July 2009
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NASA/SP–2009–566-ADD

Human Exploration of Mars
Design Reference Architecture 5.0

Addendum

Mars Architecture Steering Group
NASA Headquarters

Bret G. Drake, editor
NASA Johnson Space Center, Houston, Texas

July 2009
FOREWORD

This report serves as an Addendum to NASA/SP–2009–566, “Human Exploration of Mars Design Reference
Architecture 5.0.” The data and descriptions contained within this Addendum provide additional detail and analyses
conducted in the development of DRA 5.0. NASA/SP-2009-566 serves as the primary document describing DRA 5.0,
including potential areas where discrepancies exist with this Addendum. The individuals listed in the appendix
assisted in the generation of the concepts as well as the descriptions, images, and data described in this report. Specific
contributions to this document were provided by Dave Beaty, Stan Borowski, Bob Cataldo, John Charles, Cassie
Conley, Doug Craig, John Elliot, Chad Edwards, Walt Engelund, Dean Eppler, Stewart Feldman, Jim Garvin, Steve
Hoffman, Jeff Jones, Frank Jordan, Sheri Klug, Joel Levine, Jack Mulqueen, Gary Noreen, Hoppy Price, Shawn
Quinn, Jerry Sanders, Jim Schier, Lisa Simonsen, George Tahu, and Abhi Tripathi.

Bret G. Drake

Available from:

NASA Center for AeroSpace Information National Technical Information Service
7115 Standard Drive 5285 Port Royal Road
Hanover, MD 21076-1320 Springfield, VA 22161
Phone: [phone] or 703-605-6000
Fax: [phone]

This report is also available in electronic form at http://ston.jsc.nasa.gov/collections/TRS/
Mars Design Reference Architecture 5.0 – Addendum
CONTENTS

1 Introduction ........................................................................................................................... 1
1.1 Background and Purpose ...................................................................................................... 1
1.2 Mars Architecture Working Group ....................................................................................... 1
1.3 History of the Design Reference Architecture ...................................................................... 3
1.3.1 Office of Exploration case studies (1988)............................................................................. 4
1.3.2 Office of Exploration case studies (1989)............................................................................. 4
1.3.3 NASA 90-Day Study (1989) ................................................................................................. 5
1.3.4 The U.S. at the threshold – “The Synthesis Group” (1991) .................................................. 5
1.3.5 Mars Exploration Design Reference Missions (1994–1999) ................................................ 6
1.3.6 Decadal Planning Team/NASA Exploration Team (2000–2001) ......................................... 6
1.3.7 Integrated Space Plan (2002–2003) ...................................................................................... 7
1.3.8 Exploration Systems Mission Directorate (2004) ................................................................. 7
1.3.9 Exploration Systems Architecture Study (2005) ................................................................... 8

2 Goals and Objectives ............................................................................................................ 9
2.1 Goals ..................................................................................................................................... 9
2.1.1 Taxonomy ............................................................................................................................. 9
2.2 Mars Planetary Science Objectives (Goals I–III) ................................................................. 10
2.2.1 Introduction ........................................................................................................................... 10
2.2.2 The unique attributes of humans in scientific exploration .................................................... 10
2.2.3 Scientific objectives for Mars in the future ........................................................................... 10
2.2.4 Significance of the variation in martian geology in space and time ..................................... 12
2.2.5 Introduction to human science reference missions ............................................................... 13
2.2.5.1 Human science reference missions: geology ........................................................................ 14
2.2.5.2 Human science reference missions: geophysics ................................................................... 18
2.2.5.3 Human science reference missions: atmosphere/climate ..................................................... 22
2.2.5.4 Nominal deep drilling polar reference mission .................................................................... 27
2.2.5.5 Human science reference missions: biology/life ................................................................... 28
2.3 The Search for Extant Life .................................................................................................... 29
2.4 The Search for Past Life ....................................................................................................... 29
2.5 Human Science Reference Mission to Address Biological Goals: Centauri Montes ............ 29
2.5.1 Some summary implications for Goals I–III ......................................................................... 31
2.5.2 Conclusion ............................................................................................................................ 32
2.6 Objectives Related to Preparation for Sustained Human Presence (Goal IV+) .................. 33
2.6.1 Introduction ........................................................................................................................... 33
2.6.2 Ground rules and assumptions for later sustained human presence ...................................... 33
2.6.3 Study process ........................................................................................................................ 33
2.6.4 Major Goal IV+ objectives decomposition ........................................................................... 34
2.6.5 Study findings ....................................................................................................................... 34
2.6.5.1 Projected Mars exploration objectives for human missions one through three ................... 34
2.6.5.2 Recommendation based on Goal IV+ objectives .................................................................. 35
2.7 Objectives Related to Other Classes of Science (Goal V) ..................................................... 36
2.7.1 Heliophysics .......................................................................................................................... 36
2.7.1.1 Understanding the fundamental processes that control Mars’ space environment .............. 37
2.7.1.2 Understanding the influence of planetary magnetic fields ................................................... 37
2.7.1.3 Maximizing safety and productivity for human explorers ..................................................... 38
2.7.1.4 Reference investigation measurements for Heliophysics at Mars ........................................ 39
2.7.2 Astrophysics on Mars ........................................................................................................... 39
2.7.2.1 Laser ranging ........................................................................................................................ 40
2.7.2.2 Martian laser ranging science .............................................................................................. 40

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3 Architectural Assessments .................................................................................................... 42
3.1 Figures of Merit, Ground Rules, and Assumptions ............................................................... 43
3.1.1 Figures of merit ..................................................................................................................... 43
3.1.2 Ground rules and assumptions .............................................................................................. 45
3.2 Initial Architecture Assessments: Trade Tree Trimming ...................................................... 48
3.3 Mission Type ......................................................................................................................... 49
3.3.1 Trajectory options ................................................................................................................. 49
3.3.2 Mission design strategy ......................................................................................................... 52
3.3.3 All-up vs. pre-deploy ............................................................................................................ 52
3.3.4 Addressing key risks ............................................................................................................. 55
3.3.5 Close perihelion passage considerations ............................................................................... 55
3.3.6 Total interplanetary propulsion requirement considerations ................................................. 56
3.3.7 Total mission duration considerations .................................................................................. 57
3.3.8 Mars vicinitiy operational considerations ............................................................................. 58
3.3.8.1 Mars capture and rendezvous ............................................................................................... 58
3.3.8.2 Landing ................................................................................................................................. 59
3.3.8.3 Crew acclimation .................................................................................................................. 59
3.3.8.4 Mars orbit departure............................................................................................................. 59
3.3.8.5 Mission type comparison ...................................................................................................... 59
3.3.9 Mission sequence for the Opposition Class (short-stay) mission ......................................... 59
3.3.10 Mission sequence for the Conjunction Class (long-stay) mission ........................................ 61
3.3.11 Mission-type special considerations: science goals and objectives ...................................... 63
3.3.11.1 Opposition Class missions (short-stay): scientific position .................................................. 64
3.3.11.2 Conjunction Class missions (long-stay): scientific position ................................................. 64
3.3.12 Mission-type special considerations: human health and performance .................................. 64
3.3.12.1 Radiation risk: comparison of short- and long-surface-stay missions ................................. 66
3.3.12.2 Zero-g countermeasures ....................................................................................................... 74
3.3.12.3 Medical care and environmental health ............................................................................... 76
3.3.12.4 Human factors ....................................................................................................................... 77
3.3.13 Long-/short-mission mass comparison ................................................................................. 78
3.3.14 Long/short risk comparison .................................................................................................. 80
3.3.15 Long/short cost comparison .................................................................................................. 80
3.3.16 Long/short mission recommendation .................................................................................... 81
3.4 Mars Cargo Deployment (All-up vs. Pre-deploy) ................................................................. 82
3.4.1 Pre-deployed cargo mission option ....................................................................................... 82
3.4.2 All-up mission option ........................................................................................................... 83
3.4.3 Cargo deployment advantages and disadvantages ................................................................ 84
3.4.3.1 Advantages of the pre-deploy mission option ....................................................................... 84
3.4.3.2 Disadvantages of the pre-deploy mission option .................................................................. 84
3.4.3.3 Advantages of the all-up mission option ............................................................................... 84
3.4.3.4 Disadvantages of the all-up mission option .......................................................................... 85
3.4.4 Cargo deployment options assessments ................................................................................ 85
3.4.5 Cargo deployment recommendation ..................................................................................... 88
3.5 Mars Orbit Capture Method (Propulsive vs. Aerocapture) .................................................. 88
3.6 Mars Ascent Propellant (In-situ Resource Utilization) ......................................................... 100
3.6.1 Introduction ........................................................................................................................... 100
3.6.2 In-situ resource utilization operational concept .................................................................... 101
3.6.3 In-situ resource utilization and aborts: an emphasis on abort to the surface ......................... 102
3.6.4 Key findings .......................................................................................................................... 103
3.6.5 In-situ resource utilization trades performed ........................................................................ 103
3.6.5.1 Ground rules and assumptions ............................................................................................. 104
3.6.5.2 Mission consumables, resources, and Earth feedstock required .......................................... 104
3.6.5.3 Mars atmosphere-based options ........................................................................................... 105
3.6.5.4 Investigation Mars surface water-based options .................................................................. 107
3.6.5.5 Mars atmosphere and water-based options .......................................................................... 108
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3.6.6 Nuclear vs. solar power for Mars in-situ resource utilization ............................................... 109
3.6.7 In-situ resource utilization trade study results ...................................................................... 110
3.6.8 Parametric sizing of Mars ascent vehicle .............................................................................. 113
3.6.9 In-situ resource utilization costing ........................................................................................ 115
3.6.10 In-situ resource utilization risk considerations ..................................................................... 116
3.6.11 In-situ resource utilization conclusions and future work ...................................................... 117
3.7 Mars Surface Power ............................................................................................................. 119
3.7.1 Power requirements .............................................................................................................. 119
3.7.1.1 In-situ resource utilization phase .......................................................................................... 119
3.7.1.2 Crewed phase ........................................................................................................................ 119
3.7.2 Power profiles ....................................................................................................................... 120
3.7.3 Power system concepts ......................................................................................................... 121
3.7.3.1 Solar power system concept .................................................................................................. 121
3.7.3.2 Fission surface power system ............................................................................................... 122
3.7.3.3 Large-scale radioisotope power system ................................................................................ 122
3.7.4 Implementation considerations ............................................................................................. 123
3.7.4.1 Dust deposition ..................................................................................................................... 123
3.7.4.2 Dust storms ........................................................................................................................... 123
3.7.4.3 Deployment ........................................................................................................................... 124
3.7.4.4 Latitude constraints .............................................................................................................. 124
3.7.4.5 Operational restrictions ........................................................................................................ 124
3.7.5 Surface power recommendations .......................................................................................... 125
3.8 Planetary Protection ............................................................................................................. 126
3.8.1 Basis for planetary protection policy .................................................................................... 126
3.8.2 Planetary protection for human missions .............................................................................. 127
3.8.3 Considerations for planetary protection implementation ...................................................... 128
3.8.4 Operational constraints for human missions to Mars ............................................................ 129
3.8.5 Guidelines for practical implementation ............................................................................... 129
3.8.6 Responding to off-nominal events ........................................................................................ 130
3.8.7 Summary ............................................................................................................................... 131

4 Design Reference Architecture 5.0 Overview ...................................................................... 132
4.1 Mission Overview .................................................................................................................. 132
4.1.1 Mars Design Reference Architecture interplanetary trajectory and mission analysis ........... 133
4.1.1.1 Methodology and assumptions .............................................................................................. 133
4.1.1.2 Cargo and crew mission profiles .......................................................................................... 134
4.1.1.3 Mission information .............................................................................................................. 134
4.1.1.4 Trajectory data ..................................................................................................................... 136
4.2 Surface Reference Mission Overview.................................................................................... 138
4.3 Mission Risk and Risk Mitigation Strategy ........................................................................... 141
4.3.1 Summary ............................................................................................................................... 141
4.3.2 Methodology ......................................................................................................................... 144
4.3.3 Risk analyses ......................................................................................................................... 145
4.3.3.1 Expert estimates .................................................................................................................... 145
4.3.3.2 Simulations ............................................................................................................................ 145
4.3.3.3 Probabilistic-risk-assessment-supported calculations .......................................................... 145
4.3.3.4 Station heritage ..................................................................................................................... 145
4.3.3.5 Shuttle heritage ..................................................................................................................... 145
4.3.4 Conclusions ........................................................................................................................... 145
4.3.4.1 Sparing/modularity/scavenging ............................................................................................ 146
4.3.4.2 Precursor activities/reliability growth implications ............................................................. 147
4.3.4.3 Maximize lunar base and International Space Station synergies ......................................... 147
4.3.5 Future work ........................................................................................................................... 148
4.4 Flight Crew ........................................................................................................................... 148
4.4.1 The role of the flight crew .................................................................................................... 148
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Mars Design Reference Architecture 5.0 – Addendum
4.4.2 Top-down functional assessment of crew size ...................................................................... 149
4.4.3 Bottom-up historical assessment of crew size....................................................................... 151
4.4.3.1 Shuttle ................................................................................................................................... 151
4.4.3.2 Mir ........................................................................................................................................ 151
4.4.3.3 International Space Station ................................................................................................... 151
4.4.4 Design Reference Architecture assumed flight crew ............................................................ 153
4.5 Mission Operations ............................................................................................................... 154
4.5.1 Mission Control Center ......................................................................................................... 154
4.5.2 Automation and maintenance ................................................................................................ 154
4.5.3 Redundancy management ..................................................................................................... 154
4.5.4 Mission planning ................................................................................................................... 155
4.5.5 Integrated vehicle health monitoring .................................................................................... 156
4.5.6 Information systems .............................................................................................................. 156
4.6 Communication and Navigation ........................................................................................... 156
4.6.1 Introduction ........................................................................................................................... 156
4.6.2 Concept of operations ........................................................................................................... 157
4.6.3 Strawman communication and navigation requirements ...................................................... 159
4.6.4 Communications trade options .............................................................................................. 160
4.6.5 Baseline communications architecture .................................................................................. 162
4.6.5.1 Overview ............................................................................................................................... 162
4.6.5.2 Spectrum utilization .............................................................................................................. 162
4.6.5.3 Mars communications terminal ............................................................................................ 163
4.6.5.4 Mars relay satellite ............................................................................................................... 163
4.6.6 Position, navigation, and time considerations ....................................................................... 167
4.6.7 Heritage and key differences from the LAT communication/navigation architecture .......... 169
4.6.8 Recommendations for future work ....................................................................................... 169

5 Transportation Systems ......................................................................................................... 170
5.1 Overview ............................................................................................................................... 170
5.2 Launch Systems: Reference Vehicle ...................................................................................... 170
5.2.1 Reference vehicle: lunar mission reference shroud .............................................................. 173
5.2.2 Mars shroud options .............................................................................................................. 174
5.2.3 Mars mission low-Earth orbit analysis .................................................................................. 178
5.2.3.1 Orbits .................................................................................................................................... 179
5.2.3.2 Shroud Options A, B, and C performance ............................................................................ 179
5.2.3.3 Mars fuel stage performance ................................................................................................ 181
5.2.3.4 Dual-use aero shroud performance ...................................................................................... 181
5.2.4 Lunar/Mars mission synergism ............................................................................................. 182
5.3 Launch Processing ................................................................................................................ 182
5.3.1 Ground operations lunar baseline ......................................................................................... 183
5.3.2 Constellation Program ground systems architecture overview ............................................. 183
5.3.2.1 Block 1 – initial capability ground system architecture ....................................................... 184
5.3.2.2 Block 2 – lunar capability ground system architecture ........................................................ 184
5.3.3 Mars campaign ground processing concepts ........................................................................ 184
5.3.3.1 Mars campaign ground operations assessment .................................................................... 184
5.3.3.2 Ares V facility and ground systems options .......................................................................... 185
5.3.3.3 Flight rate and minimum launch spacing analysis and results............................................. 187
5.3.3.4 Mars campaign ground processing concepts ....................................................................... 190
5.3.3.5 Mars campaign ground processing forward work ................................................................ 193
5.4 Interplanetary Transportation .............................................................................................. 194
5.4.1 Nuclear thermal propulsion option ....................................................................................... 194
5.4.1.1 System description and performance characteristics ........................................................... 195
5.4.1.2 Mission and transportation system ground rules and assumptions ...................................... 196
5.4.1.3 Design Reference Architecture 5.0 NTR transportation system mission description .......... 198
5.4.1.4 Cargo and crewed Mars transfer vehicle design features and characteristics ..................... 199
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5.4.1.5 Summary of findings and recommended future work ............................................................ 203
5.4.2 Chemical propulsion architecture ......................................................................................... 204
5.4.2.1 Trade tree options ................................................................................................................. 204
5.4.2.2 Chemical transportation architecture overview ................................................................... 205
5.4.2.3 Mars transit vehicle chemical propulsion elements .............................................................. 206
5.4.2.4 Low-Earth orbit assembly ..................................................................................................... 207
5.4.2.5 Mars transfer vehicle analysis ground rules and assumptions ............................................. 209
5.4.2.6 Chemical Propulsion Mars transfer vehicle analysis results ................................................ 211
5.4.2.7 Application of lunar Earth departure stage for trans-Mars injection .................................. 212
5.4.2.8 Lunar and Mars architecture subsystem commonality ......................................................... 213
5.4.2.9 Chemical propulsion vehicle analysis conclusions ............................................................... 215
5.5 Crew Exploration Vehicle/Earth Return Vehicle .................................................................. 215
5.5.1 Earth return vehicle thermal protection system requirements ............................................... 216
5.5.2 Mars Earth return – entry trajectories ................................................................................... 217
5.5.3 Derived requirements: vehicle environments ........................................................................ 217
5.5.4 Thermal protection system sizing ......................................................................................... 221
5.6 Entry, Descent, and Landing ................................................................................................ 222
5.6.1 Aeroshell structural sizing .................................................................................................... 223
5.6.2 Thermal protection system sizing ......................................................................................... 224
5.6.3 Descent stage ........................................................................................................................ 225
5.6.4 Trajectory calculations .......................................................................................................... 226
5.6.5 Conclusions and recommendations ....................................................................................... 230
5.7 Mars Transit Habitat ............................................................................................................ 230
5.8 Mars Ascent/Descent Vehicle ................................................................................................ 233
5.9 Landing Plume Effects .......................................................................................................... 234
5.9.1 Summary and recommendations ........................................................................................... 234
5.9.2 Detailed analysis ................................................................................................................... 236
5.9.2.1 Background review ............................................................................................................... 236
5.9.2.2 Martian conditions ................................................................................................................ 238
5.9.2.3 Deep cratering on Mars ........................................................................................................ 239
5.9.2.4 Martian ballistics compared to terrestrial ballistics............................................................. 240
5.9.2.5 Plume and crater model ........................................................................................................ 242
5.9.2.6 Blast zone predictions ........................................................................................................... 242
5.9.2.7 Ejecta impingements on the lander ....................................................................................... 245
5.9.2.8 Regolith stability after landing ............................................................................................. 247
5.9.2.9 Additional lander mass for mitigating plume effects ............................................................ 247
5.9.2.10 Conclusions ........................................................................................................................... 248

6 Surface Systems .................................................................................................................... 249
6.1 Surface Habitats ................................................................................................................... 255
6.1.1 Approach ............................................................................................................................... 255
6.1.2 Three habitat options ............................................................................................................. 255
6.1.2.1 Mobile home ......................................................................................................................... 255
6.1.2.2 Commuter .............................................................................................................................. 256
6.1.2.3 Telecommuter ........................................................................................................................ 256
6.1.3 Ground rules and assumptions .............................................................................................. 256
6.1.4 Reference master equipment list ........................................................................................... 257
6.1.5 Summary mass and power .................................................................................................... 259
6.2 In-situ Consumable Production ............................................................................................ 260
6.2.1 Introduction ........................................................................................................................... 260
6.2.2 Ground rules and assumptions .............................................................................................. 260
6.2.3 In-situ resource utilization options concepts ......................................................................... 260
6.2.4 In-situ resource utilization options considered ..................................................................... 260
6.2.4.1 Atmospheric carbon dioxide-based options .......................................................................... 261
6.2.4.2 Surface water-based options ................................................................................................. 261
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Mars Design Reference Architecture 5.0 – Addendum
6.2.4.3 Atmospheric carbon dioxide and surface water-based options ............................................ 261
6.2.5 Surface designs ..................................................................................................................... 261
6.2.5.1 Approach ............................................................................................................................... 261
6.2.5.2 Results ................................................................................................................................... 261
6.2.6 Subsystem designs ................................................................................................................ 261
6.2.6.1 In-situ resource utilization plant (atmospheric acquisition and related subsystems) ........... 261
6.2.6.2 Excavation subsystems .......................................................................................................... 264
6.2.6.3 Water extraction subsystems ................................................................................................. 266
6.2.7 Exploratory transportation and campaign architecture considerations ................................. 270
6.2.7.1 Objectives and approach for campaign architectures analyses ........................................... 270
6.2.7.2 Mars in-situ resource utilization architecture model description ......................................... 270
6.2.7.3 Transportation architecture analysis results ........................................................................ 270
6.2.7.4 Assumptions for campaign analysis ...................................................................................... 270
6.2.7.5 Campaign results and conclusions ....................................................................................... 271
6.2.7.6 Future work ........................................................................................................................... 271
6.2.8 Conclusions and future work ................................................................................................ 271
6.3 Surface Power Systems ......................................................................................................... 272
6.3.1 Power systems analysis ......................................................................................................... 272
6.3.2 Background: Mars environmental factors ............................................................................. 272
6.3.3 Solar power design human mission design ........................................................................... 273
6.3.4 Power requirements summary ............................................................................................... 275
6.3.5 Pressurized rovers for the Mobile Home and the Telecommuter Options ............................ 279
6.4 Surface Mobility Systems ...................................................................................................... 281
6.4.1 Extravehicular activity design and operational guidelines .................................................... 283
6.4.2 Surface transportation: unpressurized and pressurized rovers .............................................. 284
6.4.2.1 Unpressurized rovers ............................................................................................................ 284
6.4.2.2 Pressurized rovers ................................................................................................................ 285
6.5 Science Systems ..................................................................................................................... 286

7 Key Challenges ..................................................................................................................... 287
7.1 Human Health and Performance .......................................................................................... 287
7.1.1 Radiation protection .............................................................................................................. 288
7.1.2 Reduced-gravity countermeasures ........................................................................................ 289
7.1.3 Medical care .......................................................................................................................... 290
7.1.4 Supporting human life ........................................................................................................... 290
7.1.5 Behavior, performance, and human factors .......................................................................... 292
7.1.6 Human health and performance critical challenges and technology needs summary ........... 293
7.2 Space Transportation ............................................................................................................ 294
7.2.1 Earth-to-orbit transportation ................................................................................................. 294
7.2.1.1 Potential upgrades to lunar campaign ................................................................................. 295
7.2.1.2 Potential alternative configurations ..................................................................................... 295
7.2.2 Advanced chemical propulsion ............................................................................................. 296
7.2.2.1 Liquid oxygen/liquid hydrogen propulsion ........................................................................... 296
7.2.2.2 Liquid oxygen/methane propulsion ....................................................................................... 297
7.2.3 Nuclear thermal propulsion ................................................................................................... 297
7.2.3.1 Nuclear thermal propulsion accomplishments and technology state-of-the-art ................... 298
7.2.3.2 Ground test facility options and development challenges ..................................................... 299
7.2.3.3 Key elements of nuclear thermal propulsion development schedule .................................... 300
7.2.3.4 Summary and recommendations ........................................................................................... 302
7.2.4 Electric propulsion ................................................................................................................ 302
7.2.5 Entry, descent, and landing ................................................................................................... 302
7.2.5.1 Mars entry descent and landing system technology (Engelund & Manning) ....................... 302
7.2.5.2 Forward work and requirements for Orion Block III TPS ................................................... 306
7.2.5.3 Mars human-scale aerocapture and entry, descent, and landing technology roadmap ....... 310
7.2.6 Space transportation critical challenges and technology needs summary ............................. 314
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