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Origin and Mineralogy of Lunar Meteorites. a Study for Lunar Mining and Resources Exploitation

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Origin and Mineralogy of Lunar Meteorites. a Study for Lunar Mining and Resources Exploitation Master in Aerospace Engineering Esther Mas Sanz Origin and mineralogy of Lunar meteorites. A study for lunar mining and resources exploitation Master’s Final Degree Project - Report Director: Dr. Josep M. Trigo-Rodríguez (CSIC-IEEC) Tutor: Dr. Miquel Sureda Anfres (UPC) Course: 2019-2020, Spring Semester Delivery date: 22nd June, 2020 [This page intentionally left blank] Acknowledgements I want to express my gratitude to the director of my Master Thesis, Dr. Josep M. Trigo- Rodríguez, for his support throughout the project and particularly, during the difficult situation we all have lived under the pandemic of covid-19. Despite the limitations this project has been possible, perhaps not as complete as firstly imagined but still, robust and rewarding. Likewise, I thank Dr.Miquel Sureda for promptly solving all of my doubts and the ESEIAAT administration for rapidly adapting the course to the new circumstances. I also appreciate the effort of my family and beloved ones, for making these hard times easier to bear and for their unconditional support. Finally, my most sincere gratitude for all of those who, during the coronavirus crisis, have taken care of the most vulnerable and those who have ensured that the gears of society kept working. Thank you all. Abstract In recent years the Moon has become once again the target for many of the most ambitious space projects. Our satellite is expected to provide a permanent base by 2030s and open new possibilities for deep-space exploration and the conquest of Mars. During this decade it is paramount to expand our knowledge on lunar surface mineralogy, chemistry and geology; to prospect it and lay the foundations for the future exploitation of its resources. Lunar achondrites provide interesting information about the main rock-forming minerals of the Moon. These rocks were excavated and delivered to Earth by continuous collisions going on the surface of our satellite. Unfortunately we do not know the exact region of origin of these rocks, so the information provided is only partial. This Master Thesis will study the physico-chemical properties of Lunar meteorites, and will also study the main dynamic pathways followed by Lunar meteorites reaching planet Earth. I declare that, the work in this Master Thesis is completely my own work, no part of this Master Thesis is taken from other people’s work without giving them credit, all references have been clearly cited, I understand that an infringement of this declaration leaves me subject to the foreseen disciplinary actions by Universitat Politècnica de Catalunya - BarcelonaTECH. Student Name: Signature: Date: Esther Mas Sanz 22nd June, 2020 Title of the Thesis: Origin and mineralogy of Lunar meteorites. A study for lunar mining and resources exploitation. Lunar Meteorites: Origin and Mineralogy CONTENTS Contents List of Figures iii List of Tablesv 1 Introduction4 1.1 The Moon, our closest neighbour ....................... 4 1.1.1 A New Race to the Moon: Lunar Mining ............... 6 1.2 Meteoritics .................................... 8 1.2.1 Meteorite classification ......................... 9 1.2.2 Differentiated Meteorites: Achondrites . 10 1.3 Lunar Meteorites ................................ 11 1.3.1 Lunaites Classification ......................... 12 1.3.2 Recovery Locations ........................... 14 1.4 Lunar Geochemistry .............................. 15 1.4.1 Inorganic constituents in Lunar Soil . 17 1.5 Lunar Ejecta .................................. 20 1.5.1 CREAs ................................. 20 I Mineralogy Study 23 2 Chemical and mineralogical characterization of lunar achondrites 23 2.1 SEM+EDX ................................... 23 2.1.1 Solver for Mineral Proportions ..................... 24 3 Lunar Meteorite Samples 27 3.1 JaH 838 ..................................... 27 3.1.1 SEM/EDX Microscopy Results .................... 29 i Lunar Meteorites: Origin and Mineralogy CONTENTS 3.2 Dho 1084 .................................... 33 3.2.1 SEM/EDX Microscopy Results .................... 34 3.3 NWA 11444 ................................... 37 3.3.1 SEM/EDX Microscopy Results .................... 38 3.4 Results Summary ................................ 45 3.5 Conclusions ................................... 47 II Orbital Dynamics Study 49 4 Introduction 49 4.1 Software and Databases ............................ 49 4.2 Previous Works ................................. 50 5 Simulations of Lunar Ejecta 51 5.1 Short transfers ................................. 54 5.1.1 Variation of launch direction ...................... 54 5.1.2 Variation of Ejection Angle ...................... 66 5.1.3 Variation of Earth-Moon-Sun configuration . 71 5.1.4 Summary of results ........................... 76 5.2 Long transfers .................................. 77 5.2.1 Case study: Meteorite Impact on the Moon . 84 5.2.2 Summary of results ........................... 92 6 Conclusions 93 7 Future Work 96 8 Planning 97 Bibliography 98 ii Lunar Meteorites: Origin and Mineralogy LIST OF FIGURES List of Figures 1.1 Representations of the Moon in prehistory and ancient cultures . 4 1.2 Apollo 17 astronaut collecting samples .................... 5 1.3 Water content on the Moon .......................... 7 1.4 Classification diagram of meteorites [72] ................... 10 1.5 Lunar meteorites recovery sites statistical analysis. Database for analysis can be found in [36] ............................... 14 1.6 Images of the Moon surface .......................... 15 1.7 Examples of geochemical bimodality of pristine non-mare rocks. 17 1.8 Images of metals on the Moon surface ..................... 18 1.9 Images of thorium (correlated to KREEP) on the Moon surface . 18 1.10 Cumulative percentage impacted with Earth . 22 2.1 Energy dispersive X-ray spectrum ....................... 24 2.2 Ternary diagram of of the composition of feldspar minerals. 25 3.1 Location of the JaH 838 meteorite ....................... 27 3.2 Mosaic of JaH 838 ............................... 29 3.3 Meteorite JaH 838 ROIs ............................ 30 3.4 Spectrum 6 JaH 838 .............................. 30 3.5 SEM/EDX mapping of JaH 838 ........................ 32 3.6 Location of the Dho 1084 meteorite ...................... 33 3.7 Mosaic of DHO 1084 .............................. 34 3.8 Meteorite DHO 1084 ROI ........................... 35 3.9 Spectrum 3 of the mapping of DHO 1084 ................... 36 3.10 Mosaic of NWA 11444 ............................. 38 3.11 ROIs of NWA 11444 .............................. 39 3.12 Spectrum 3 of the mapping of NWA 11444 (ROI 1) . 40 iii Lunar Meteorites: Origin and Mineralogy LIST OF FIGURES 3.13 Spectrum 1 of the mapping of NWA 11444, ROI 2 . 41 3.14 Spectrum 1 of the mapping of NWA 11444 (ROI 3) . 43 3.15 SEM/EDX mapping of NWA 11444 ...................... 44 5.1 Moon Launching Sites ............................. 51 5.2 Launching sites and velocities for different directions of launch and ejection angles ...................................... 52 5.3 Moon coordinates ................................ 53 5.4 Velocity vectors in mooncentric and geocentric orbits . 53 5.5 Variation of Earth impacts with launch velocity . 58 5.6 Trajectories of two particles in geocentric orbits . 59 5.7 Evolution of the meteoroid impact population . 60 5.8 Evolution of the meteoroid impact population (logarithmic scale) . 61 5.9 Launch angle of particles according to their launch site. 62 5.10 Correlation between launch site and Earth collisions with varying launch direction ..................................... 63 5.11 Correlation between launch site and Earth collisions with varying launch direction at different times. ........................... 64 5.12 Histogram of Earth Impacts as function of ejection angle and ejection velocity 67 5.13 Flat view of the four histograms for Earth Impacts as function of ejection angle and ejection velocity ........................... 67 5.14 Comparison between ejection angles ...................... 69 5.15 Launch angle of particles according to their launch site . 70 5.16 Different Earth-Moon-Sun configurations for lunar ejecta launches . 72 5.17 Earth impacts for different velocities and initial dates . 73 5.18 Minimum time for a lunar ejecta to impact with Earth (histogram) . 75 5.19 Minimum time for a lunar ejecta to impact with Earth . 75 5.20 Evolution of launch angles for long time scales. 78 5.21 Initial orbital elements. ............................. 79 5.22 Final orbital elements. ............................. 79 5.23 Semi-major axis vs. eccentricity evolution in time . 80 5.24 Lunar ejecta survivor population after 105 years. 81 iv Lunar Meteorites: Origin and Mineralogy LIST OF TABLES 5.25 Accumulated impacts % ............................ 83 5.27 Detailed map of the Moon surface. ...................... 85 5.28 Impact point and directions of launch for the lunar ejecta. 86 5.29 Distribution of lunar ejecta after 104 years. 86 5.30 Orbital elements at collision instant. ..................... 87 5.31 Orbital elements at collision instant. ..................... 88 5.32 Orbital elements evolution of M184. ...................... 89 5.33 Time evolution of the orbital elements for different ejected particles. 90 5.34 Histogram of Earth collisions. ......................... 91 8.1 Gantt Diagram. ................................. 97 List of Tables 1.1 Denomination of object and phenomena according to diameter range. See [71], [70], [72]. .................................. 9 1.2 Main mineral components found in meteorites [73].
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