Human Missions to Mars: Enabling Technologies for Exploring the Red Planet

Preface
What´s New in Third Edition?
Contents
List of Figures
List of Tables
Chapter 1: Why Explore Mars?
1.1 Introduction
1.2 Robotic Exploration - The Establishment View
1.3 The Curmudgeons´ View on the Search for Life on Mars
1.4 Why Send Humans to Mars? - The Enthusiasts´ View
1.5 Sending Humans to Mars - The Skeptic´s View
References
Chapter 2: Planning Space Campaigns and Missions
2.1 Architectures
2.2 Campaigns
2.3 Planning Space Missions
2.4 A Mission as a Sequence of Steps
2.5 Mars Mission Architectures
2.6 System Engineers
References
Chapter 3: 60+ Years of Humans to Mars Mission Planning
3.1 von Braun´s Vision
3.2 Earliest NASA Concepts
3.2.1 First Studies
3.2.2 Studies in the Early 1960s
3.2.3 Nuclear Rocket Development
3.3 The Boeing Study of 1968
3.4 Early Mars Planning Exterior to NASA
3.4.1 The Planetary Society and the SAIC Analysis
3.4.2 The Case for Mars II
3.5 NASA in the Late 1980s
3.5.1 LANL
3.5.2 Sally Ride Study
3.5.3 SAIC
3.5.4 Office of Exploration Case Studies (1988)
3.5.5 Office of Exploration Case Studies (1989)
3.5.6 The Space Exploration Initiative and its Successors
3.5.7 LANL
3.6 Independent Studies of the 1990s
3.6.1 The Soviets
3.6.2 Mars Direct
3.6.3 The Mars Society Mission
3.7 The Pre-DRM Era
3.8 NASA Design Reference Missions 1993-2007
3.8.1 Design Reference Mission-1 (DRM-1)
3.8.2 Design Reference Mission-3 (DRM-3)
3.8.3 Mass Comparisons: DRM-3 and DRM-1
3.8.4 ISRU System for DRM-3
3.8.5 Design Reference Mission-4 (DRM-4)
3.8.6 Dual Landers Mission
3.8.7 Design Reference Architecture-5 (DRA-5)
3.8.8 Exploration Strategy Workshop (2006)
3.9 Other Mars Mission Concepts
3.9.1 TeamVision Approach to Space Exploration
3.9.2 The MIT Study
3.9.3 ESA Concurrent Design Facility Study (2003)
3.9.4 HERRO Missions to Mars Using Telerobotic Surface Exploration from Orbit
3.9.5 Boeing in the Twenty-First Century
3.9.6 Free Return Missions
3.9.7 Short Stay vs. Long Stay Missions
3.9.8 Architectures Based on Flyby and Free Return Trajectories
3.9.9 VASIMR Human Mission to Mars (2011)
3.9.10 Fast Nuclear Mission (2013)
3.9.11 Mars Base Camp (2016)
3.9.12 Crewed Mars Options Using Nuclear Electric Propulsion
3.9.13 NTP Missions Analysis by Aerojet Rocketdyne
3.9.14 IAA Study 2011-2015
3.9.15 Phobos Mission
3.9.16 24-Day Mars Surface Stay
3.9.17 Austere Human Mission to Mars
3.10 Twenty-First Century NASA Activities
3.10.1 NASA Activity 2009-2015
3.10.2 Feasibility of Human Mission to Mars by 2033
3.10.3 NASA Mars Study Capability Team 2017-2018
3.10.4 NASA Plan for Human Mars Exploration 2021
3.10.5 NASA Plan for Human Mars Missions (2022)
3.10.5.1 Introduction
3.10.5.2 Overview of Mission
3.10.5.3 Mission Subsystems
3.10.5.4 Summary: NASA Plans for Mars in the 2020s
3.11 Crew Size and Crew Function
3.11.1 Crew Size and Makeup
3.11.1.1 Introduction
3.11.1.2 Review of Some Studies on Crew Size
3.11.1.3 Crew Size in Proposed Human Missions to Mars
3.11.1.4 Psychological Aspects
3.11.1.5 Earth Simulations and Analogs
3.11.1.6 Summary
References
Chapter 4: Getting There and Back
4.1 Impulsive Propulsion Systems
4.1.1 Impulsive Propellant Requirements for Space Transits
4.1.2 The Rocket Equation
4.1.3 Dry Mass of Rockets
4.2 Impulsive Trajectory Analysis
4.2.1 Rocket Science 101
4.2.1.1 Constants of Motion
4.2.1.2 Energy of an Orbit
4.2.1.3 Measured Values for the Sun, Earth, and Mars
4.2.1.4 Escaping the Influence of a Planet
4.2.1.5 Earth and Mars Solar Orbit Velocities
4.2.1.6 Hohmann Transfer to Mars
4.2.1.7 Earth and Mars Low Orbit Velocities
4.2.1.8 Earth Escape
4.2.1.9 Mars Orbit Insertion - Part 1
4.2.1.10 Summary of Transfers to and from Hohmann Orbit
4.2.1.11 Orbital Period
4.2.1.12 Mars Orbit Insertion - Part 2
4.2.1.13 Summary
4.2.2 Mars Mission Duration and Propulsion Requirements
4.2.3 More Realistic Models
4.3 Earth to Low Earth Orbit
4.4 Departing from LEO
4.4.1 The Δv Requirement
4.4.2 Mass Sent Toward Mars
4.4.3 Nuclear Thermal Propulsion for TMI
4.4.4 Solar Electric Propulsion for Orbit Raising
4.5 Mars Orbit Insertion
4.6 Ascent from the Mars Surface
4.6.1 Propellant Mass/Payload Mass
4.7 Trans-Earth Injection from Mars Orbit
4.8 Earth Orbit Insertion
4.9 Gear Ratios
4.9.1 Introduction
4.9.2 Gear Ratio Calculations
4.9.3 Gear Ratio for Earth Departure
4.10 LEO to Mars Orbit
4.11 LEO to the Mars Surface
4.12 IMLEO for Mars Missions
4.12.1 Chemical Propulsion and Aeroassist
4.12.2 Use of Nuclear Thermal Propulsion
4.12.3 Use of ISRU
4.13 Mars Missions Utilizing Nuclear Thermal Propulsion
4.13.1 Nuclear Thermal Propulsion
4.13.2 Borowski et al.
4.13.3 One-Year Short Stay Mission
4.13.4 Aerojet Mars Missions Utilizing NTP
4.14 Chemical Propulsion vs. Nuclear Propulsion
4.15 Mars Missions Utilizing Solar Electric Propulsion
References
Chapter 5: Critical Mars Mission Elements
5.1 Environmental Control and Life Support Consumables
5.1.1 Consumable Requirements (Without Recyling)
5.1.2 Use of Recycling Systems - As of 2015
5.1.3 Use of Recycling Systems - Update 2022
5.1.3.1 2022 Update
5.1.3.2 Open and Closed Life Support Systems
5.1.4 ECLSS Summary
5.2 Radiation Effects and Shielding Requirements
5.2.1 Radiation Sources
5.2.2 Definitions and Units
5.2.3 Radiation Effects on Humans and Allowable Dose
5.2.4 Radiation in Space
5.2.5 Radiation Levels in Mars Missions
5.2.6 Radiation Summary
5.3 Effects of Microgravity
5.3.1 Introduction to Generic Effects of Zero g
5.3.2 Reviews of Low-g Effects
5.3.3 Artificial Gravity
5.3.4 NASA Plans for Low-g Effects
5.4 Human Factors in Confined Space
5.5 Abort Options and Mission Safety
5.5.1 Abort Options and Mission Safety in ESAS Lunar Missions
5.5.2 Abort Options in Mars Missions
5.5.2.1 NASA Missions
5.5.2.2 The Mars Society Mission
5.5.2.3 Abort Options Conclusions
5.5.3 Acceptable Risk
5.6 Habitats
5.6.1 Habitat Design and Human Factors
5.6.2 Terrestrial Analogs of Mars Habitats
5.6.3 DRM-1 Habitats
5.6.4 DRM-3 Habitats
5.6.5 Dual Landers Habitat
5.6.6 SICSA Habitat Designs
5.6.7 Additional Habitat Concepts 2022
5.6.8 The Orion Crew Exploration Vehicle
5.7 Aero-Assisted Orbit Insertion and Entry, Descent and Landing
5.7.1 Introduction
5.7.2 Experience with Robotic Spacecraft
5.7.3 Entry Descent and Landing Requirements for Human Missions to Mars
5.7.3.1 Georgia Tech: Initial Results
5.7.3.2 Georgia Tech: Second Results
5.7.3.3 Georgia Tech: Third Results
5.7.3.4 EDL for Crewed Landing
5.7.3.5 Additions - 2022
5.7.4 Precision Landing
5.7.5 Development, Test and Validation Roadmaps
5.8 Vehicles
5.8.1 Mars Ascent Vehicle and Ascent from Mars
5.8.1.1 Background
5.8.1.2 Introduction
5.8.1.3 Crew Size
5.8.1.4 The Crew Capsule and the Crew
5.8.1.5 Ascent: The Polsgrove et al. 2015 Study
5.8.1.6 Ascent: Polsgrove et al. (2017)
5.8.1.7 Delft University Study
5.8.1.8 Required ISRU Production Rates for Ascent Propellants
5.8.2 Crew Transport Vehicle to and from Mars
References
Chapter 6: In Situ Utilization of Indigenous Resources
6.1 Value of ISRU
6.2 Lunar ISRU
6.2.1 Introduction
6.2.2 Ascent Propellants
6.2.3 Life Support Consumables
6.2.4 Propellants Delivered to LEO from the Moon
6.2.5 Propellants Delivered to Lunar Orbit for Descent (and Ascent)
6.2.6 Regolith for Radiation Shielding
6.2.7 Visionary Concepts
6.2.8 Lunar Resources and Processes
6.2.8.1 Oxygen from FeO in Regolith
6.2.8.2 Oxygen from Regolith Silicates
6.2.8.3 Extracting Putative Volatiles
6.2.8.4 Utilizing Polar Ice Deposits
6.2.8.5 NASA Study of Lunar ISRU Using Polar Ice
6.2.9 Cost Analysis for Lunar ISRU
6.3 Mars ISRU
6.3.1 Introduction
6.3.2 Timeline for ISRU on Mars
6.3.3 Mars ISRU Products
6.3.4 Mars ISRU Processes
6.3.4.1 Oxygen Production by Solid Oxide Electrolysis
6.3.4.2 The Reverse Water Gas Shift Process
6.3.4.3 The Sabatier/Electrolysis Process
6.3.4.4 Sabatier-Electrolysis Process Based on Indigenous Mars Water
6.3.4.5 CO2 Acquisition from the Mars Atmosphere
6.3.4.6 Absorbing Oxygen from the Atmosphere
6.3.4.7 Plasma Conversion and Membrane Separation
6.3.5 Modeling Full-Scale Mars ISRU Using CO2 Electrolysis to Produce Oxygen
6.3.5.1 Mass, Power and Run Options
6.3.5.2 Run Options
6.3.5.3 Recent NASA Analysis
6.3.6 Reduction in IMLEO from Use of ISRU in Human Mission to Mars
6.3.6.1 Introduction
6.3.6.2 Injecting the ERV into Orbit and Departing from Orbit
6.3.6.3 Ascent from Mars to Rendezvous on Orbit
6.3.6.4 Total Mass Approaching Mars and IMLEO
6.4 Fueling Mars-Bound Vehicles from Extraterrestrial Resources
6.4.1 Lunar Resources
6.4.2 Value of Lunar Water in LEO
6.4.3 Percentage of Water Mined on the Moon Transferred to LEO
6.4.3.1 Transfer Via LL1
6.4.3.2 Dependence on Junction Site
6.4.4 Near-Earth Object Resources
6.5 Lunar Ferry for Lunar Descent Propellants
6.6 Staging, Assembly and Refueling in Near-Earth Space
6.6.1 Orbiting Fuel Depots
6.6.1.1 Introduction
6.6.1.2 Propellants for Earth Departure
6.6.1.3 Propellant Depots in LEO Filled by Delivery from Earth
6.6.2 On-Orbit Staging
6.7 Hydrogen in Space or on Mars
6.7.1 Options for Hydrogen Storage
6.7.1.1 Storage as a Cryogenic Liquid
6.7.1.2 Storage as a Dense gas at Reduced Temperature
6.7.1.3 Storage as Solid Hydrogen
6.7.1.4 Storage as Solid-Liquid Slush
6.7.1.5 Storage as Hydrogen at Its Triple Point
6.7.2 Boil-Off in a Spacecraft
6.7.2.1 Rate of Boil-off from MLI Insulated Tanks
6.7.2.2 Mass Effect of Boil-off in Space
6.7.3 Zero Boil-Off Systems
6.7.3.1 Results from 2nd Edition
6.7.3.2 Update 2022
6.7.4 Storage on Mars
6.7.5 Summary and Conclusions
References
Chapter 7: Why the NASA Approach Will Likely Fail to Send Humans to Mars for Many Decades to Come
7.1 The Moon-Mars Connection
7.1.1 Differences Between Lunar and Mars Missions
7.1.2 The Moon as a Means of Risk Reduction for Mars
7.1.3 ISRU as a Steppingstone from Moon to Mars
7.2 Characteristics of the Mars Campaign
7.3 Destination-Driven vs. Constituency-Driven Programs
7.4 Need for New Technology
7.5 NASA Technology Roadmaps
7.6 Space Science Enterprise (SSE)
7.6.1 SSE Scope of Technology
7.6.2 Lead Centers
7.6.3 SSE Technology Summary
7.7 Human Exploration Technology
7.7.1 Technology for Human Exploration at NASA
7.7.2 Dramatic Changes in the Last Decade
7.8 Future Prospects
7.8.1 Constraints
7.8.2 Clarifying Mars Mission Options
7.8.3 Fundamental Needs
7.8.3.1 Propulsion Systems
7.8.3.2 Aero-Assisted Entry, Descent and Landing
7.8.3.3 Habitats, Capsules and Pressurized Rovers
7.8.3.4 Life Support Consumables
7.8.3.5 In Situ Resource Utilization
7.8.3.6 Power Systems
7.8.3.7 Health Care
7.8.3.8 Site Selection
7.8.3.9 Precursor Missions at Mars
7.8.3.10 Mitigation of Dust Effects
7.8.3.11 Testing in Earth Orbit
7.9 Does NASA HEO Have the Needed Mentality?
7.10 Conclusions
References
Appendix A: Solar Energy on the Moon
A.1. First Approximation to Lunar Orientation
A.2. Solar Insolation on a Horizontal Surface
A.3. Solar Insolation on a Vertical Surface
A.4. Insolation on a Surface Tilted at Latitude Angle Toward the Equator
A.5. A Surface That Is Always Perpendicular to the Solar Rays
A.6. Effect of Non-ideal Lunar Orbit
A.7. Operating Temperature of Solar Arrays on the Moon
A.8. Solar Energy Systems at the Equator
A.8.1 Short-Term Systems (<354 h)
A.8.2 Long-Term Systems (>354 h)
A.9. Effects of Dust
A.10. Solar Energy Systems in Polar Areas
A.10.1 Polar Sites
A.10.2 GRC Solar Polar Study
Appendix B: Solar Energy on Mars
B.1 Solar Intensities in Current Mars Orbit
B.1.1 Introduction
B.1.2 Irradiance in a Clear Atmosphere
B.1.3 Effect of Atmosphere
B.1.3.1 The Direct Beam
B.1.3.2 Simple ``Two-Flux´´ Model of Scattering and Absorption of Sunlight in the Mars Atmosphere
B.1.3.3 Sophisticated Model of Scattering and Absorption of Sunlight in the Mars Atmosphere
B.2 Solar Intensities on a Horizontal and Tilted Surfaces
B.2.1 Nomenclature
B.2.2 Solar Intensity on a Horizontal Surface
B.3 Solar Intensities on a Fixed Tilted Surface
B.3.1 The Diffuse Component on a Tilted Surface
B.3.2 Reflection from Ground in Front of Tilted Collector
B.3.3 Total Intensity on a Tilted Surface
B.3.4 Rotating Tilted Surfaces
B.4 Numerical Estimates of Solar Intensities on Mars
B.4.1 Solar Energy on Horizontal Surfaces
B.4.1.1 Daily Total Insolation
B.4.1.2 Hourly Insolation Patterns on a Horizontal Surface
B.4.1.3 Total Insolation on a Horizontal Surface over a Martian Year
B.4.2 Solar Intensities on Sloped Surfaces
B.4.2.1 Fixed Slope Surfaces
B.4.2.2 Rotating Sun-Facing Tilted Planes
B.4.3 Solar Energy on Mars over the Last Million Years
B.4.3.1 Variations in the Mars Orbit
B.4.3.2 Insolation on Horizontal Surfaces over a Million Years
B.4.3.3 Insolation on Tilted Surfaces over a Million Years
B.5 Effect of Dust on Array Surfaces - Simple Models
B.5.1 Introduction
B.5.2 Optical Depth
B.5.3 Particle Size Distribution
B.5.4 Number of Dust Particles in Vertical Column
B.5.5 Rate of Settling of Dust Particles
B.5.6 Initial Rate of Obscuration
B.5.7 Longer Term Buildup of Dust
B.6 Pathfinder and MER Data on Dust Obscuration
B.7 Aeolian Removal of Dust from Surfaces
B.8 Obscuration Produced by Dust on Solar Arrays
B.8.1 JPL Experiments - 2001
B.8.2 Summary and Conclusions on Dust Obscuration
Appendix C: Water on Mars
C.1 Introduction
C.2 Background Information
C.2.1 Temperatures on Mars
C.2.2 Pressures on Mars
C.2.3 Water Vapor Concentrations on Mars
C.3 Equilibrium Models for Subsurface Ice
C.3.1 Introduction
C.3.2 Models for Stability of Subsurface Ground Ice on Mars - Current Conditions
C.3.3 Long-Term Evolution of Water on Mars
C.3.4 Effect of Mars Orbit Variations During the Past ~1 Million Years
C.3.5 Evolution of South Polar Cap
C.4 Experimental Detection of Water in Mars Subsurface by Observation from Orbit
C.4.1 Introduction to Neutron Spectroscopy
C.4.2 Data Reduction - Neutron Spectroscopy
C.4.3 Water Content Based on Uniform Regolith Model Using Neutron Spectroscopy
C.4.4 Water Content Based on a Two-Layer Regolith Model at Equatorial and Mid-Latitudes
C.4.5 Interpretation of Depth from Neutron Measurements
C.4.6 Evidence for Unusually High Hydrogen Abundances (2022)
C.4.7 Ice Exposed in Recent Impacts
C.4.8 Ice in High-Latitude Northern Craters
C.4.9 Surface Ice from IR Measurements
C.5 Comparison of Neutron Data with Physical Properties of Mars
C.5.1 Surface and Atmospheric Properties
C.5.2 Water Deposits vs. Topography at Low and Mid Latitudes
C.5.3 Seasonal Distribution of Equatorial Near-Surface Water
C.5.4 Water in the Mars Surface from IR Reflectance Spectra
C.5.5 Mineral Hydration and Adsorbed Water
C.6 The Polar Caps
C.7 Liquid Water on Mars
C.7.1 Regions Where Surface Temperature Excursions Exceed 273.2 K
C.7.2 Liquid Water Below the Surface
C.7.3 Brines
C.7.4 Imaging Indications of Recent Surface Water Flows
C.7.4.1 Gullies
C.7.4.2 Surface Streaks
C.8 Evidence from Craters
C.8.1 Introduction
C.8.2 The Work of Nadine Barlow (and Friends)
C.8.3 Other Crater Studies
C.8.4 Commentary
C.9 Summary
References
Appendix A
Appendix B
Appendix C
Glossary
Index