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NASA NTRS2007

Cyanobacteria for Human Habitation beyond Earth

In light of the President s Moon/Mars initiative, lunar exploration has once again become a priority for NASA. In order to establish permanent bases on the Moon and proceed with human exploration of Mars, two key problems will be addressed: first, the production of O2 and second, the production of methane (CH4). While O2 is required for life support systems (LSS), both liquid O2 and CH4 are needed as an oxidizer and a propellant, respectively for the Lunar Surface Access Module (LSAM) and the Crew Exploration Vehicle (CEV). Unlike previous propulsion systems, the new CEV will use liquid oxygen (LO2) as an oxidizer and liquid methane (LCH4) as a propellant. Existing technology (e.g. hydrogen reduction) for the production of liquid oxygen from lunar regolith is very energy intensive and requires high temperature reactors. We propose an alternative approach using iron-tolerant cyanobacteria. We have found that iron-tolerant cyanobacteria (IT CB) are capable of etching iron-bearing minerals, which may lead to bonds breaking between Fe and O of common lunar mare basalt Fe-oxides including ilmenite, pseudobrookite, ferropseudobrookite, and armalcolite with the subsequent release of both Fe, Ti and oxygen as byproducts. We also propose to use CB biomass for CH4 production as carbon stock and a propellant. Both processes can be accomplished in an energy and cost effective manner because sunlight will be used as an energy source and allows the reactions at ambient temperatures between 10-60 C. Current evaluations include assessing the thermodynamics of such biogenic reactions using a variety of nutrients and atmospheric parameters, as well as assessing the rates and species variation effects of the driving reactions.

Brown, Igor↗

NASA NTRS2014

The Oxygen and Volatile Extraction Node (OVEN) Subsystem for Resource Prospector

The OVEN (Oxygen and Volatile Extraction Node) Subsystem is part of the RESOLVE (Regolith and Environment Science & Oxygen and Lunar Volatile Extraction) Payload, whose main objective is to verify the presence of water and other volatiles on the lunar surface. The RESOLVE payload is scheduled to fly to the moon as part of the Resource Prospector (RP) in 2019. The OVEN Subsystem accepts regolith (soil) and evolves the volatiles contained in the sample by heating the segment to a temperature of at least 150oC for volatile analysis and as high as 900oC for hydrogen reduction. In general, a regolith segment is deposited into a crucible; the crucible is heated and evolved gases flow to a gas analyzer.

Paz, Aaron↗

NASA NTRSDate not supplied

Degradation of Yttria-Stabilized Zirconia in Molten Regolith Electrolysis Applications

The generation of oxygen from lunar resources is an enabling technology to support a sustained human presence on the lunar surface. Molten regolith electrolysis is a promising process for directly electrolyzing lunar regolith, which is primarily a mixture of oxide minerals. During electrolysis, metallic products (Fe, Si) are formed at the cathode and oxygen is produced at the anode. In order to perform electrolysis, the regolith must be molten to enable ionic transport of metallic cations and oxygen anions, requiring an operating temperature of 1600C. Common refractory oxide materials, such as Al2O3 and MgO, undergo rapid degradation due to the high operating temperature and contact with the corrosive molten regolith. This work investigates yttria-stabilized zirconia (YSZ) for molten regolith electrolysis applications. Corrosion studies are presented to elucidate the degradation mechanism of YSZ powders and crucibles exposed to lunar regolith simulants at 1600C. Two regolith simulants are used to represent regolith from the lunar maria (JSC-1A) and the lunar highlands (LHS-1). Degradation of YSZ in contact with regolith simulants is evaluated using SEM/EDS, XRD, and EBSD. Furthermore, a modified molten regolith electrolysis reactor is presented utilizing YSZ at the anode to enable facile collection of oxygen produced during electrolysis.

Kevin Yu↗

NASA NTRS2011

NASA Lunabotics Mining Competition for Universities: Results and Lessons Learned

Space Mining for resources such as water ice, and regolith, which contain many elements in the form of metals, minerals, volatiles and other compounds, is a necessary step in Space Resource Utilization. One of the primary goals is to extract propellants from the regolith such as oxygen and hydrogen which could then be used for in-space transportation. In addition, the space mining system can be used for various construction tasks that can benefit human and robotic exploration as well as scientific investigations based on the exposed topography. The National Aeronautics & Space Administration (NASA) Lunabotics Mining Competition is a university-level competition designed to engage and retain students in science, technology, engineering and mathematics (STEM). NASA will directly benefit from the competition by encouraging the development of innovative lunar excavation concepts from universities which may result in clever ideas and solutions which could be applied to an actual lunar excavation device or payload. The challenge is for students to design and build a remote controlled or autonomous excavator, called a lunabot, that can collect and deposit a minimum of 10 kilograms of lunar simulant within 15 minutes. The complexities of the challenge include the abrasive characteristics of the lunar simulant, the weight and size limitations of the lunabot, and the ability to control the lunabot from a remote control center. This paper will present the results of the first and second annual Lunabotics Mining Competitions held in May 2010 and May 2011. In 2010, 22 United States (US) universities competed, and in May 2011 the competition was opened to international participation, with 46 Universities expected to attend. There are 12 international teams and 34 US teams. This combined total directly inspired an estimated 544 university students. More students and the public were engaged via internet broadcasting and social networking media. The various designs will be cataloged and categorized to provide information to future Lunabotics mining robot designers and competitors. It is also expected to be of value for actual future space missions, as knowledge is gained from testing many innovative prototypes in simulated lunar regolith.

Mueller, Robert P.↗

NASA NTRS2012

Lunabotics Mining Competition: Inspiration through Accomplishment

Space Mining for resources such as water ice, and regolith, which contain many elements in the form of metals, minerals, volatiles and other compounds, is a necessary step in Space Resource Utilization. One of the primary goals is to extract propellants from the regolith such as oxygen and hydrogen which could then be used for in-space transportation. In addition, the space mining system can be used for various construction tasks that can benefit human and robotic exploration as well as scientific investigations based on the exposed topography. The National Aeronautics & Space Administration (NASA) Lunabotics Mining Competition is a university-level competition designed to engage and retain students in science, technology, engineering and mathematics (STEM). NASA will directly benefit from the competition by encouraging the development of innovative lunar excavation concepts from universities which may result in clever ideas and solutions which could be applied to an actual lunar excavation device or payload. The challenge is for students to design and build a remote controlled or autonomous excavator, called a lunabot, that can collect and deposit a minimum of 10 kilograms of lunar simulant within 15 minutes. The complexities of the challenge include the abrasive characteristics of the lunar simulant, the weight and size limitations of the lunabot, and the ability to control the lunabot from a remote control center or operate autonomously. This paper will present an update of the results and lessons learned during the first and second annual Lunabotics Mining Competitions held in May 2010 and May 2011. It will also preview the 2012 competition with a review of the revised rules. In 2010,22 United States (US) universities competed, and in May 2011 the competition was opened to international participation. In 2011, 36 teams actually competed from 26 USA states and 4 foreign countries (India, Bangladesh, Colombia and Canada). This combined total directly inspired an estimated 653 university students. In 2012 more students and the public will be engaged via internet broadcasting and social networking media. The various designs will be cataloged and categorized to provide information to future Lunabotics mining robot designers and competitors. It is also expected to be of value for actual future space missions, as knowledge is gained from testing many innovative prototypes in simulated lunar regolith.

Mueller, Robert P.↗

NASA NTRS2009

Lunar Oxygen Production and Metals Extraction Using Ionic Liquids

Initial results indicate that ionic liquids are promising media for the extraction of oxygen from lunar regolith. IL acid systems can solubilize regolith and produce water with high efficiency. IL electrolytes are effective for water electrolysis, and the spent IL acid media are capable of regeneration.

Marone, Matthew↗

NASA NTRS2010

Potential Lunar In-Situ Resource Utilization Experiments and Mission Scenarios

The extraction and use of resources on the Moon, known as In-Situ Resource Utilization (ISRU), can potentially reduce the cost and risk of human lunar exploration while also increasing science achieved. By not having to bring all of the shielding and mission consumables from Earth and being able to make products on the Moon, missions may require less mass to accomplish the same objectives, carry more science equipment, go to more sites of exploration, and/or provide options to recover from failures not possible with delivery of spares and consumables from Earth alone. The concept of lunar ISRU has been considered and studied for decades, and scientists and engineers were theorizing and even testing concepts for how to extract oxygen from lunar soil even before the Apollo 11 mission to the Moon. There are four main areas where ISRU can significantly impact how human missions to the Moon will be performed: mission consumable production, civil engineering and construction, energy production, storage, and transfer, and manufacturing and repair. The area that has the greatest impact on mission mass, hardware design and selection, and mission architecture is mission consumable production, in particular, the ability to make propellants, life support consumables, and fuel cell reagents. Mission consumable production allows for refueling and reuse of spacecraft, increasing power production and storage, and increased capabilities and failure tolerance for crew life support. The other three areas allow for decreased mission risk due to radiation and plume damage, alternative power systems, and failure recover capabilities while also enabling infrastructure growth over Earth delivered assets. However, while lunar ISRU has significant potential for mass, cost, and risk reduction for human lunar missions, it has never been demonstrated before in space. To demonstrate that ISRU can meet mission needs and to increase confidence in incorporating ISRU capabilities into mission architectures, terrestrial laboratory and analog field testing along with robotic precursor missions are required. A stepwise approach with international collaboration is recommended. The first step is to understand the resources available through orbital and surface exploration missions. Resources of particular interest are hydrogen, hydroxyl, water, and other polar volatile resources recently measured by Chandrayaan, Lunar Reconnaissance Orbiter (LRO), and the Lunar Crater Observation and Sensing Satellite (LCROSS). The second step is to demonstrate critical aspects of ISRU systems to prove ISRU is feasible under lunar environmental and resource conditions (ex. subscale oxygen extraction from regolith). The third step is to perform integrated missions with ISRU and other connected systems, such as power, consumable storage, surface mobility, and life support at a relevant mission scale to demonstrate ISRU capabilities as well as the critical interfaces with other exploration systems. If possible, the mission should demonstrate the use of ISRU products (ex. in a rocket engine or fuel cell). This dress rehearsal mission would be the final step before full implementation of ISRU into human missions, and may be performed during human lunar exploration activities. This stepwise approach is the most conservative approach, and may only be possible with international cooperation due to the limited number of robotic missions each nation/space agency can perform within their budget.

Sanders, Gerald B.↗

NASA NTRS2010

The In-Situ Resource Utilization Project Under the New Exploration Enterprise

The In Situ Resource Utilization Project under the Exploration Technology Development Program has been investing in technologies to produce Oxygen from the regolith of the moon for the last few years. Much of this work was demonstrated in a lunar analog field demonstration in February of 2010. This paper will provide an overview of the key technologies demonstrated at the field demonstration will be discussed a long with the changes expected in the ISRU project as a result of the new vision for Space Exploration proposed by the President and enacted by the Congress in the NASA Authorization Act of2010.

Larson, William E.↗

NASA NTRS2011

High Temperature Microwave Dielectric Properties of JSC-1AC Lunar Simulant

Microwave heating has many potential lunar applications including sintering regolith for lunar surface stabilization and heating regolith for various oxygen production reactors. The microwave properties of lunar simulants must be understood so this technology can be applied to lunar operations. Dielectric properties at microwave frequencies for a common lunar simulant, JSC-1AC, were measured up to 1100 C, which is approximately the melting point. The experimentally determined dielectric properties included real and imaginary permittivity (epsilon', epsilon"), loss tangent (tan delta), and half-power depth, the di stance at which a material absorbs 50% of incident microwave energy. Measurements at 2.45 GHz revealed tan delta of JSC-1A increases from 0.02 at 25 C to 0.31 at 110 C. The corresponding half-power depth decreases from a peak of 286 mm at 110 C, to 13 mm at 1100 C. These data indicate that JSC-1AC becomes more absorbing, and thus a better microwave heater as temperature increases. A half-power depth maximum at 100-200 C presents a barrier to direct microwave heating at low temperatures. Microwave heating experiments confirm the sluggish heating effect of weak absorption below 200 C, and increasingly strong absorption above 200 C, leading to rapid heating and melting of JSC-1AC.

Allan, Shawn M.↗

NASA NTRS2011

Solar Panel Integration as an Alternate Power Source on Centaur 2 (SPIAPS)

The dream of exploration has inspired thousands throughout time. Space exploration, in particular, has taken the past century by storm and caused a great advance in technology. In this project, a retractable solar panel array will be developed for use on the Centaur 2 Rover. Energy generated by the solar panels will go to power the Centaur 2 Robot (C2) or Regolith & Environment Science & Oxygen & Lunar Volatile Extraction (RESOLVE) payload, an in-situ resource utilization project. Such payload is designed to drill into lunar and Martian terrain as well as be able to conduct other geological testing; RESOLVE is slated for testing in 2012. Ultimately, this project will fit into NASA s larger goal of deep space exploration as well as long term presence outside Earth s orbit.

Gebara, Christine A.↗

NASA NTRS2011

Development and Demonstration of Sustainable Surface Infrastructure for Moon/Mars Exploration

For long-term human exploration of the Moon and Mars to be practical, affordable, and sustainable, future missions must be able to identify and utilize resources at the site of exploration. The ability to characterize, extract, processes, and separate products from local material, known as In-Situ Resource Utilization (ISRU), can provide significant reductions in launch mass, logistics, and development costs while reducing risk through increased mission flexibility and protection as well as increased mission capabilities in the areas of power and transportation. Making mission critical consumables like propellants, fuel cell reagents and life support gases, as well as in-situ crew/hardware protection and energy storage capabilities can significantly enhance robotic and human science and exploration missions, however other mission systems need to be designed to interface with and utilize these in-situ developed products and services from the start or the benefits will be minimized or eliminated. This requires a level of surface and transportation system development coordination not typically utilized during early technology and system development activities. An approach being utilized by the US National Aeronautics and Space Administration and the Canadian Space Agency has been to utilize joint analogue field demonstrations to focus technology development activities to demonstrate and integrate new and potentially game changing. mission critical capabilities that would enable an affordable and sustainable surface infrastructure for lunar and Mars robotic and human exploration. Two analogue field tests performed in November 2008 and February 2010 demonstrated first generation capabilities for lunar resource prospecting, exploration site preparation, and oxygen extraction from regolith while initiating integration with mobility, science, fuel cell power, and propulsion disciplines. A third analogue field test currently planned for June 2012 will continue and expand the fidelity and integration of these surface exploration and infrastructure capabilities while adding Mars exploration technologies, improving remote operations and control of hardware, and promoting the use of common software, interfaces, & standards for control and operation for surface exploration and science. The next field test will also attempt to include greater involvement by industry, academia, and other countries/space agencies. This paper will provide an overview of the development and demonstration approach utilized to date, the results of the previous two ISRU-focused field analogue tests in Hawaii, and the current objectives and plans for the 3rd international Hawaii analogue field test.

Sanders, Gerald B.↗

NASA NTRS2015

Space Resource Utilization: Technologies and Potential Synergism with Terrestrial Mining

Space Resources and Their Uses: The idea of using resources in space to support human exploration and settlement or for economic development and profit beyond the surface of Earth has been proposed and discussed for decades. Work on developing a method to extract oxygen from lunar regolith started even before humans set foot on the Moon for the first time. The use of space resources, commonly referred to as In Situ Resource Utilization (ISRU), involves the processes and operations to harness and utilize resources in space (both natural and discarded) to create products for subsequent use. Potential space resources include water, solar wind implanted volatiles (hydrogen, helium, carbon, nitrogen, etc.), vast quantities of metals and minerals in extraterrestrial soils, atmospheric constituents, unlimited solar energy, regions of permanent light and darkness, the vacuum and zero-gravity of space itself, trash and waste from human crew activities, and discarded hardware that has completed its primary purpose. ISRU covers a wide variety of concepts, technical disciplines, technologies, and processes. When considering all aspects of ISRU, there are 5 main areas that are relevant to human space exploration and the commercialization of space: 1. Resource Characterization and Mapping, 2. In Situ Consumables Production, 3. Civil Engineering and Construction, 4. In Situ Energy Production and Storage, and 5. In Situ Manufacturing.

Sanders, Gerald B.↗

NASA NTRS2015

Development of the Resource Prospector Planetary Rover

The Resource Prospector (RP) is an In-‐Situ Resource Utilization (ISRU) lunar rover mission under study by NASA. RP is planned to launch in 2020 to prospect for subsurface volatiles and to extract oxygen from lunar regolith. The mission will address several of NASA's "Strategic Knowledge Gaps" for lunar exploration. The mission will also address the Global Exploration Roadmap's strategic goal of using local resources for human exploration. The distribution of lunar subsurface volatiles drives the mission requirement for mobility. The spatial distribution is hypothesized to be governed by impact cratering with the top 0.5 m being patchy at scales of 100 m. The mixing time scale increases with depth (less frequent larger impacts). Consequently, increased mobility reduces the depth requirement for sampling. The target RP traverse will extend 1 km radially from the landing site to sample craters of varying sizes. Sampling craters with different ages will reveal possible volatile emplacement history. In 1 Ga, approximately 60-70 craters of 10 m diameter form per km2. Thus, the rover will need to sample at least ten of these craters, which may require a total traverse path length of 2-‐3 km. During 2014-2015, we developed an initial prototype rover for RP. The current design is a solar powered, four-wheeled vehicle, with hub motor drive, offset four wheel steering, and active suspension. Active suspension provides capabilities including changing vehicle ride height, traversing comparatively large obstacles, and controlling load on the wheels. All-wheel steering enables the vehicle to point arbitrarily while roving, e.g., to keep the solar array pointed at the sun while in motion. The offset steering combined with active suspension improves driving in soft soil. The rover's on-board software utilizes NASA's Core Flight Software, which is a reusable flight software environment. During 2015, we completed the initial rover software build, which provides low-level hardware interfaces, basic mobility control, waypoint driving, odometry, basic error checking, and camera services. Development of the prototype rover has enabled maturation of many of the subsystems to TRL 5. During the next year, we will conduct integrated testing of concepts of operation, navigation, and remote driving tools. In addition, we will perform environmental tests including radiation (avionics), thermal and thermal/vacuum (mechanisms), and gravity offload (mobility).

robotics↗

NASA NTRSDate not supplied

Plasma for the Space Environment: An Overview of the Research at NASA's Kennedy Space Center

Human life amongst other planets requires vast technological advancements to sustain nutritional, environmental, and logistical needs. Plasma systems allow for advanced chemical processing while mitigating consumable needs or reliance on industrial infrastructure. Scientists at NASA’s Kennedy Space Center are attempting to close technology gaps with research into plasmas and their applications. Some such work includes the use of plasma for waste gasification, water activation, nutrient recovery techniques, lunar regolith reduction for oxygen extraction, and space crop production support. Here we report on the needs, success criteria, and results of plasma efforts for crewed transit and planetary habitation.

Plasma↗

NASA NTRSDate not supplied

Carbothermal Reduction Demonstration (CaRD) 22 Technology Review

The Carbothermal Reduction Demonstration project will demonstrate the ability to extract oxygen from lunar regolith using concentrated solar energy. The goal of this project is to raise the TRL of a system that can demonstrate these functions on the lunar surface. The project concludes with a ground demonstration in a relevant environment.

Aaron Paz↗

NASA NTRSDate not supplied

Update on NASA’s ISRU Development and Mission Plans for the Artemis Program

In 2017, NASA initiated the Artemis program to send astronauts back to the lunar surface, create a sustainable human lunar exploration program, and lead the first human exploration mission to the Mars surface. While much of NASA’s plans for the Artemis program currently focus on the Human Lunar Return and the ability for astronauts to explore the lunar surface for limited durations each year, the longer-term vision for the Artemis program is to enable sustained human exploration and commercial operations in cis-lunar space and the lunar surface. An important aspect of achieving this long-term vision, is to better understand and characterize the resources on the Moon and Mars and learn how to extract and use these resources. Known as In Situ Resource Utilization (ISRU), the identification, mapping, extraction, and processing of space resources has the potential to greatly reduce the cost and risk of human exploration. These are achieved by reducing what needs to be delivered from Earth and the dependency on these supplies, lowering costs through commercial operations, and expanding infrastructure for safer and more capable exploration and surface operations. To guide development of ISRU technologies and systems on the ground and demonstrate these capabilities on the Moon and Mars, the NASA Space Technology Mission Directorate (STMD) created and released the ISRU Envisioned Future Priorities (EFP) strategic plan in 2022 and updated it in 2023. While lunar ISRU technology development had already started, these publicly released strategic plans have been used to guide and prioritize technology development, and assess the progress in achieving the vision. Since the release of the ISRU EFP, there have been several significant activities/events that have occurred with respect to human lunar exploration, surface infrastructure, and ISRU. One was the release of the Artemis Architecture Definition Document Revision 1 that included ISRU as a sub-architecture. The second was the release of several STMD solicitations including the Announcement of Collaborative Opportunities (ACO) and Tipping Point (TP). The third was the release of a Request for Information for the Lunar Infrastructure Foundational Technology-1 (LIFT-1) mission with the primary objective of extracting oxygen from lunar regolith. The fourth was the release of STMD technology and capability Shortfalls, and the review, ranking by numerous stakeholders and individuals, and subsequent prioritization of the Shortfalls that will be utilized in future solicitation and development plans. This paper will provide an overview and status of on-going technology and system development activities, an update of ISRU into the Artemis campaign, an update on ISRU-related mission, and the impacts of the Shortfall prioritization.

NASA↗

NASA NTRS2010

Field Scale Testing of RESOLVE at 2010 ISRU Analog Test

When mankind returns to the moon, there will be one aspect of the architecture that will totally change how we explore the solar system. For the first time in space exploration, we will take the initial steps towards breaking our reliance on Earth-supplied consumables by extracting resources from planetary bodies. Our first efforts in this area, known as In Situ Resource Utilization (ISRU), will be directed at extracting some of the abundant oxygen found in the lunar regolith. But the "holy grail" of lunar ISRU will be finding an exploitable source of lunar hydrogen. If we can find a source of hydrogen that can be reasonably extracted from the regolith, it would provide a foundation for true independence from Earth consumables. With in-situ hydrogen and oxygen (and/or water) we can produce many of the major consumables needed to travel to and operate on a sustainable lunar outpost. We would have water to drink, oxygen to breath, and rocket propellants and fuel cell reagents to enable extended access and operations across the moon. NASA initiated development of an experiment package named RESOLVE (Regolith & Environment Science and Oxygen & Lunar Volatile Extraction) that could be flown to the rim or into a permanently shadowed crater to answer the questions surrounding elevated hydrogen at the lunar poles.

Captain, Janine E.↗

NASA NTRS2010

Thermal Properties of Lunar Regolith Simulants

Various high temperature chemical processes have been developed to extract oxygen and metals from lunar regolith. These processes are tested using terrestrial analogues of the regolith. But all practical terrestrial analogs contain H2O and/or OH(-), the presence of which has substantial impact on important system behaviors. We have undertaken studies of lunar regolith simulants to determine the limits of the simulants to validate key components for human survivability during sustained presence on the moon. Differential Thermal Analysis (DTA) yields information on phase transitions and melting temperatures. Themo-Gravimetric Analysis (TGA) with mass spectrometric (MS) determination of evolved gas species yields chemical information on various oxygenated volatiles (water, carbon dioxide, sulfur oxides, nitrogen oxides and phosphorus oxides) and their evolution temperature profiles. The DTA and TGAMS studies included JSC-1A fine, NU-LHT-2M and its proposed feed stocks: anorthosite; dunite; HQ (high quality) glass and the norite from which HQ glass is produced. Fig 1 is a data profile for anorthosite. The DTA (Fig 1a) indicates exothermic transitions at 355 and 490 C and endothermic transitions at 970 and 1235 C. Below the 355 C transition, water (Molecular Weight, MW, 18 in Fig 1c) is lost accounting for approximately 0.1% mass loss due to water removal (Fig 1b). Just above 490 C a second type of water is lost, presumably bound in lattices of secondary minerals. Between 490 and the 970 transition other volatile oxides are lost including those of hydrogen (third water type), carbon (MW = 44), sulfur (MW = 64 and 80), nitrogen (MW 30 and 46) and possibly phosphorus (MW = 79, 95 or 142). Peaks at MW = 35 and 19 may be attributable to loss of chlorine and fluorine respectively. Negative peaks in the NO (MW = 30) and oxygen (MW = 32) MS profiles may indicate the production of NO2 (MW = 46). Because so many compounds are volatilized in this temperature range quantification of the mass loss associated with individual species is difficult. Similar information will be presented for the other materials studied in this investigation.

Street, Kenneth↗