The Mars 2020 Perseverance rover landing site is located within Jezero crater, a  $\sim50~\mbox{km}$ diameter impact crater interpreted to be a Noachian-aged lake basin inside the western edge of the Isidis impact structure. Jezero hosts remnants of a fluvial delta, inlet and outlet valleys, and infill deposits containing diverse carbonate, mafic, and hydrated minerals. Prior to the launch of the Mars 2020 mission, members of the Science Team collaborated to produce a photogeologic map of the Perseverance landing site in Jezero crater. Mapping was performed at a 1:5000 digital map scale using a 25 cm/pixel High Resolution Imaging Science Experiment (HiRISE) orthoimage mosaic base map and a 1 m/pixel HiRISE stereo digital terrain model. Mapped bedrock and surficial units were distinguished by differences in relative brightness, tone, topography, surface texture, and apparent roughness. Mapped bedrock units are generally consistent with those identified in previously published mapping efforts, but this study’s map includes the distribution of surficial deposits and sub-units of the Jezero delta at a higher level of detail than previous studies. This study considers four possible unit correlations to explain the relative age relationships of major units within the map area. Unit correlations include previously published interpretations as well as those that consider more complex interfingering relationships and alternative relative age relationships. The photogeologic map presented here is the foundation for scientific hypothesis development and strategic planning for Perseverance’s exploration of Jezero crater.

By the time of the 2022 IAC, NASA's Mars2020 Perseverance rover will have spent 18 months on the surface of Mars, during which time the MOXIE experiment (Mars OXygen ISRU Experiment) will have produced oxygen at night and in the day during both the annual maximum and minimum atmospheric density periods, as well as at many other times during the year. MOXIE is the first demonstration of the use of indigenous resources (ISRU = In Situ Resource Utilization) on the surface of another planet. This paper will present a summary of what MOXIE has accomplished, how its performance on Mars has changed with time, and plans for the future. The paper will also present results from an optimization study of a human-scale MOXIE-type system capable of providing the oxidizer for a 6–person Mars Ascent Vehicle. As an experiment carried inside the rover, MOXIE had to satisfy many constraints that would not apply to an independent, full-scale system. Other potential oxygen-producing technologies should be compared to the optimized human-scale system results summarized in this paper rather than to a simple linear scaling of the mass, power consumption, and oxygen production rate of MOXIE.

The Mars Oxygen ISRU Experiment (MOXIE) is an instrument onboard NASA’s Perseverance rover. On April 20th, 2021, MOXIE generated oxygen on Mars from the carbon dioxide present in the Martian atmosphere, demonstrating, for the first time, in-situ resource utilization (ISRU) on the surface of another celestial body. Learnings from MOXIE on Mars have aided in the design of a scaled-up version of MOXIE. Oxygen generated from this scaled-up system would be used as propellant in a Mars Ascent Vehicle that would enable the crew to return to Earth once their mission was complete, as well as in life support systems. Failure of any of its subsystems would result in a loss of mission due to the inability of the crew to return to Earth. Accordingly, risk analysis is one of the most crucial steps in the design of the scaled-up MOXIE that must be completed and understood before building and launching the system to Mars. The intent of this paper is to present a comprehensive, quantitative analysis of the operational risks associated with this Mars ISRU plant. We then present an approach to optimize the reliability of each subsystem using a modified probabilistic risk assessment and heuristics-based optimization algorithm.

This study modeled the performance of a full-scale Mars in situ resource utilization (ISRU) system to produce 30 metric tons of liquid O-2, operated for 14 months at half-hourly intervals as the Mars environment changes diurnally and seasonally. We considered various control options, with particular emphasis on power requirements and required cell voltages. Mars temperature and pressure data at half-hour intervals were obtained from the Mars Perseverance team. The full-scale Mars ISRU system included a mechanical compressor, high-temperature electrolysis of Martian CO2, and a liquefier to produce liquid oxygen. The key factors were (a) maintaining cell voltage well below the Nernst potential for carbon formation from CO and (b) tracking the maximum power, as well as the range of power required, at each half-hourly junction across the 14-month run for each control option. The most favorable control option involved adjusting the compressor revolutions per minute at each half-hour to produce a quasi-steady state of oxygen production in the electrolysis and the liquefaction systems, resulting in the most benign electrolysis settings, the lowest maximum power, and the narrowest range of required power. Other approaches where the compressor was run at a steady state and the oxygen production rate varied with time led to higher electrolysis voltage, higher maximum power, and a wider range of power. This study provides guidance on the optimum operating conditions and power requirements of a Mars ISRU system to produce 30 metric tons of liquid oxygen in 14 months of operation.

Exploration of space has always held a certain fascination for humankind. Stepping foot on the Moon may have been the achievement of the century, and sending humans to Mars will be even more challenging and exciting. To achieve self-sufficiency off the Earth, humans will need a steady supply of food while also maintaining adequate mental health. We propose here a closed-loop ecosystem that accomplishes both while being feasible to transport, construct, and maintain on Mars. The resulting design, MarsGarden, is capable of providing a crew of four astronauts with all their dietary needs and also acting as a place of relaxation and restoration. MarsGarden is a scalable architecture that can be adapted to many deep space environments, or can be implemented on Earth as an agricultural solution for areas with land scarcity or extreme environments.

NASA is in the processes of evaluating various architectures that may support human missions to Mars. A multitude of concepts are being traded and associated sensitivities are being analyzed. Among these trades, several options for Mars Ascent Vehicle (MAV) propellant supply are being considered. Due to mass constraints on the Mars descent system and the in-space transportation system, landing a fully fueled MAV, that can launch humans from the surface of Mars, presents significant integrated architecture challenges. Consequently, MAV propellant must either be pre-positioned and transferred across the surface robotically or made on the surface via In-Situ Resource Utilization (ISRU) techniques. In each case, there are implications to the number of architecture elements, total system mass, power requirements, complexity of operations, and required technology developments. An analysis that compares an ISRU point solution to a similar point solution that pre-positions and transfers propellant is detailed.

The Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE) is a technology demonstration on the NASA Mars 2020 Perseverance rover. MOXIE is capable of producing 6-10 g/h of oxygen via solid oxide electrolysis of atmospheric carbon dioxide. The Mars 2020 mission has allocated MOXIE a minimum of ten oxygen-producing runs, each with approximately 1 h of oxygen production. Before landing, operations were planned to meet MOXIE's five success criteria. Run structure, constraints, and thorough definition and validation processes were defined. Before producing oxygen for the first time, several checkouts were planned to verify functionality of MOXIE's major subsystems. MOXIE's first oxygen-producing run was planned to produce up to 6 g/h of oxygen for approximately 1 h and measure a conservative range of current and voltage at two inlet mass flow rates. The remaining oxygen-producing runs were planned to measure performance using the largest permissible range of current, voltage and inlet mass flow rate for a wide range of atmospheric densities. Runs were designed to be flexible, allowing modification as operational knowledge accumulates throughout the mission. Validation of runs using models and hardware has demonstrated that MOXIE is ready for surface operations.

MOXIE [Mars Oxygen In Situ Resource Utilization (ISRU) Experiment] is the first demonstration of ISRU on another planet, producing oxygen by solid oxide electrolysis of carbon dioxide in the martian atmosphere. A scaled-up MOXIE would contribute to sustainable human exploration of Mars by producing on-site the tens of tons of oxygen required for a rocket to transport astronauts off the surface of Mars, instead of having to launch hundreds of tons of material from Earth's surface to transport the required oxygen to Mars. MOXIE has produced oxygen seven times between landing in February 2021 and the end of 2021 and will continue to demonstrate oxygen production during night and day throughout all martian seasons. This paper reviews what MOXIE has accomplished and the implications for larger-scale oxygen-producing systems.

MOXIE is a technology demonstration that addresses the Mars 2020 (Perseverance) objective of preparing for future human exploration by demonstrating In Situ Resource Utilization (ISRU) in the form of dissociating atmospheric CO2 into O2. The primary goals of the MOXIE project are to verify and validate the technology of Mars ISRU as a springboard for the future, and to establish achievable performance requirements and design approaches that will lead to a full-scale ISRU system based on MOXIE technology. MOXIE has three top-level requirements: to be capable of producing at least 6 g/hr of oxygen in the context of the Mars 2020 mission (assuming atmospheric intake at 5 Torr, typical of Jezero Crater, and $0~^{\circ}\text{C}$ , typical of the rover interior); to produce oxygen with $>98\%$ purity; and to meet these first two requirements for at least 10 operational cycles after delivery. Since MOXIE is expected to operate in all seasons and at all times of day and night on Mars, these requirements are intended to be satisfied under worst-case environmental conditions, including during a dust storm, if possible.

The manned exploration of Mars is a demanding goal, requiring a large amount of resources. Among them, oxygen is without doubt pivotal since it is needed for the crew to breathe and for the Mars Ascent Vehicle to fuel the return journey to the Earth. In light of this, In-Situ Resource Utilization (ISRU) practices become useful. We know that carbon dioxide constitutes about 96% of Martian atmosphere and it is the candidate for oxygen extraction through a Solid Oxide Electrolysis reaction. The Mars Oxygen ISRU Experiment (MOXIE) demonstrator proved this concept on board of the Perseverance Rover in April 2021. A full-scale device suitable for a human mission, called L-MOXIE, will be more than 200 times larger. In this work, we evaluate the power requirements of L-MOXIE through process simulations obtaining a consumption of 22.8 kW. This result suggests a thorough redesign of the power generation system. To perform this design activity, we employ a forcing technique based on C-K theory pillars to broaden the spectrum of options retrieved from the literature review. The degrees of freedom are design variables associated with the power generation technology, the power transmission system and the power storage system while the constraints are set forth by the Martian environment, the oxygen handling and storage requirements, and the overall system safety and maintenance requirements. From the partial solutions, we build a morphological chart, and three concepts are then generated based on nuclear, grounded solar, and orbiting photovoltaic Power Generation System. We performed a Multi-Attribute Utility Analysis (MAUA) to assess them, and the nuclear and grounded solar concepts proved more attractive than the orbiting photovoltaic concept. These results are intended to support future activities such as a feasibility analysis and a multi-objective optimization for the nuclear and grounded solar concept.

The Mars Oxygen ISRU Experiment (MOXIE) is an instrument traveling to Mars onboard NASA's Perseverance rover. It will demonstrate, for the first time ever, in-situ resource utilization (ISRU) on the surface of another celestial body. MOXIE will utilize the carbon dioxide atmosphere of Mars to create oxygen as a demonstration of a planned larger mission. The instrument itself will produce oxygen at roughly 0.5 percent of the scale that would be necessary to support a human mission to Mars. A scaled-up version of MOXIE would be sent to Mars twenty-six months ahead of the first human mission and would aim to produce approximately 3 kg/hr of oxygen while in operation. This production rate would fully fuel the oxidizer portion of a Mars Ascent Vehicle prior to the first crew landing on Mars, which would enable that crew to return to Earth. This is a key capability to reduce mission risk by providing a safe return option on Mars prior to the crew arriving. Additionally, the system could provide oxygen for life support systems and habitation pressure. The intent of this paper is to describe a model that has been created to optimize the design of this scaled ISRU plant. It takes lessons learned from the MOXIE project and combines them with parameters and constraints of a planned human mission to systematically identify optimal design solutions. The extensibility of MOXIE is formulated through a multiobjective optimization problem for early-stage conceptual design. The objective functions minimize the power and mass required to build this ISRU system by changing operating conditions and system architecture while satisfying a set of constraints. The subsystems modeled for this problem include carbon dioxide acquisition and compression (CAC) to compress the Mars atmosphere, solid oxide electrolysis (SOE) to produce oxygen from carbon dioxide, and liquefaction to prepare the oxygen for storage. Additionally, the power, electronics, and heat exchange systems are simulated to capture gas transfer and control mechanisms. The model is built in MATLAB and uses Simulink as a framework. Results from this multiobjective optimization study and an analysis on the scalability of the MOXIE instrument show that an ISRU system that produces 22,717 kg of oxygen over 14 months would have a mass of 7,512 kg and a power requirement of 19,526 W. These results provide NASA and other agencies with an optimized design of a scaled ISRU system and its potential to reduce cost and risk as they prepare for a human mission to Mars.

NASA is interested in characterising and robotically exploring the lunar permanently shadowed regions (PSRs) in advance of Artemis crewed landings. The challenging terrain of these regions means a lander would only be able to access the rim of a PSR, limiting line-ofsight communication and sensing into the PSR. Autonomously deployed lunar tower infrastructures could provide valuable lines of sight into and around these PSRs. NASA has developed deployable composite booms for use in microgravity, and we propose an extension of those capabilities by deploying a composite boom vertically in the lunar gravity field. Services hosted by the elevated platform at the top of the boom, such as power beaming, radio repeaters, or imagers, could support the near-term operations of multiple distributed, mobile, robotic assets as well as long-term regional operations of exploration crews. The

NASA is interested in characterizing and robotically exploring the lunar permanently shadowed regions (PSRs) in advance of Artemis crewed landings. The challenging terrain of these regions means a lander would only be able to access the rim of a PSR, limiting line-of-sight communication and sensing into the PSR. Autonomously deployed lunar tower infrastructures could provide valuable lines of sight into and around these PSRs. NASA has developed deployable composite booms for use in microgravity, and we propose an extension of those capabilities by deploying a composite boom vertically in the lunar gravity field. Services hosted by the elevated platform at the top of the boom, such as power beaming, radio repeaters, or imagers, could support the near-term operations of multiple distributed, mobile, robotic assets as well as long-term regional operations of exploration crews. The Multifunctional Expandable Lunar Lightweight, Tall Tower (MELLTT) design, created by our interdisciplinary team of MIT graduate and undergraduate students in October 2019, has been selected and funded by NASA STMD and Space Grant as a finalist in the National Institute of Aerospace’s NASA BIG Idea 2020 Challenge and will be demonstrated at the virtual BIG Idea Forum in January 2021. The expected result of this work is a proof-of-concept of a TRL 4 prototype of a deployable, tall lunar tower by January 2021, setting the stage for future development along a path to flight targeting an early 2020’s lunar tower technology demonstration mission in support of the Artemis program.

The Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE) represents the first time that NASA is demonstrating In-Situ Resource Utilization (ISRU) on the surface of another planetary body. MOXIE will produce oxygen from atmospheric CO2 on Mars. It is being developed for NASA's 2020 Mars Rover and will produce greater than 99.6% pure oxygen through solid oxide electrolysis. MOXIE is roughly 0.5% of the scale that would be necessary to produce oxygen for breathing and use as a propellant for a human Mars mission. Tests are being performed on MOXIE in the laboratory at NASA's Jet Propulsion Laboratory (JPL) and the Massachusetts Institute of Technology (MIT). At the same time, a model is being developed to simulate and predict the performance of MOXIE. The ability to predict the performance of MOXIE on Mars is a critical step in preparation for surface operations. Without the ability to estimate inefficient or unsafe operating conditions, MOXIE operations on Mars run a spectrum of risk ranging from loss of efficiency to the loss of the entire mission. Therefore, to predict performance and thus avoid subjecting flight hardware to unsafe conditions, a dynamic model has been developed that simulates MOXIE's operation. Simulink, a package contained within the MATLAB programming language, was chosen as a convenient way to build this dynamic representation of MOXIE. The model is a combination of theoretical and empirical values regarding the gas flows, thermal transfers, electrochemistry, and control loops that are representative of the true MOXIE system. The results of this model have been validated against data from JPL's MOXIE testbed laboratory. This paper gives an overview of how MOXIE works and how it is modeled. MOXIE is the first instrument of its kind to leave the Earth, and the modeling of this instrument is similarly unique. As the dynamic model continues to evolve with new data, it becomes a fast and inexpensive way to test MOXIE without subjecting expensive hardware to hazardous conditions.