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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 469 records · Page 26
All sourcesNASA NTRSDOE OSTI
NASA NTRS1998

Processing Glass Fiber from Moon/Mars Resources

Processing of Lunar/Mars raw materials into usable structural and thermal components for use on a Lunar/Mars base will be essential for human habitation. One such component will be glass fiber which can be used in a number of applications. Glass fiber has been produced from two lunar soil simulants. These two materials simulate lunar mare and lunar highlands soil compositions. Short fibers containing recrystallized areas were produced from the as-received simulants. Doping the highland simulant with 8 weight percent boria yielded a material which could be spun continuously. The effects of lunar gravity on glass fiber formation were studied utilizing NASA's KC 135 aircraft. Gravity was found to play a role in crystallization and final fiber diameter.

Tucker, Dennis S.↗
DOE OSTI2023

Assessing the Behavior of Moderately Volatile Elements on the Moon in Order to Constrain Processes of Magmatic Evolution and Planetary Accretion

Heterogeneous isotopic compositions of Zn and Ga in lunar basalts and highlands rocks indicate that secondary processing affected the stable isotopic composition of major lunar reservoirs. It follows that these fractionating processes must be identified and characterized in order to make robust estimates for the isotopic composition of the mare basalt source regions or the bulk silicate Moon (BSM). Contrary to previous assertions (e.g., Kato & Moynier, 2017), MVEs such as Zn and Ga do not behave similarly on the Moon, in line with differences in their chemical behavior and volatility. There is clear evidence that impact reworking fractionates zinc isotopes but, in addition, zinc isotopes are also highly sensitive to the formation of Ti-bearing oxides such as ilmenite. In contrast, gallium is far less susceptible to volatile reworking, but its isotopic composition is fractionated during incorporation into plagioclase (Wimpenny et al., 2022; Render et al., 2023). Based on these findings we conclude that current isotopic compositions of Zn and Ga in lunar rocks, such as those measured for the mare basalt suite, are unlikely to be representative of the bulk Moon when it accreted. As such, estimates for the MVE isotopic composition of the BSM derived from mare basalts may not be accurate, which may have implications for the incorporation of these data into dynamical models of the Moon’s formation. In the following, we discuss the main findings from this project in more detail, focusing on the behaviour of zinc and gallium isotopic systematics in lunar rocks and the processes that control their isotopic fractionation on the Moon.

58 GEOSCIENCES↗
NASA NTRS1983

Bibliography

A bibliography of articles entered into the data base at the Lunar and Planetary Institute Library from November 1982 through January 1983 is presented. An abstract of each article is given. The subjects covered by the articles include: the motion of the moon and dynamics of the earth-moon system: shape and gravity field of the moon; the physical structure of the moon, its thermal and stress history; the morphology of the lunar surface, the origin and stratigraphy of lunar formations, and mapping of the moon; the chemical composition of the moon, lunar petrology, mineralogy, and crystallography; electromagnetic properties of the moon; the planets; and other objects, including asteroids, comets, meteorites, and cosmic dust.

Kopal, Z.↗
NASA NTRS1992

Basaltic impact melts in the Apollo collections: How many impacts and which events are recorded?

Many of the rocks in the Apollo collections from the lunar highlands are impact melt breccias of basaltic bulk composition. They are known by a variety of names including low-K Fra Mauro basalt, VHA basalt, and basaltic impact melts. These rocks have been studied to understand the compositional nature of the lunar crust, to decipher the processes of large body impact, and to comprehend the record of impact bombardment of the Moon. Study of terrestrial craters has led to a model for impact melt generation whereby target lithologies are totally melted during impact. The impact melt makes up a few percent of the total volume of crater material; superheated silicate liquids of the impact melt have extremely low viscosities and mix intimately. This mixing thoroughly homogenizes the melt chemically during the excavation of the crater. Colder, unmelted debris is overridden by the melt sheet as the crater cavity grows. Incorporation of these cold clasts rapidly chills the melt, with zones of greater and lesser amounts of clasts being primarily responsible for modestly differing thermal regimes. The net effect of this process is the production of a suite of rocks that have extreme chemical homogeneity, but wide petrographic diversity. Strict application of this model to the petrogenesis of basaltic impact melts from the Moon has some fairly significant consequences for how we interpret early lunar history. The consequences are briefly discussed.

Spudis, Paul D.↗
NASA NTRS1992

Glass fiber processing for the Moon/Mars program: Center director's discretionary fund final report

Glass fiber has been produced from two lunar soil simulants. These two materials simulate lunar mare soil and lunar highland soil compositions, respectively. Short fibers containing recrystallized areas were produced from the as-received simulants. Doping the highland simulant with 8 weight percent B2-O3 yielded a material which could be spun continuously. The effects of lunar gravity on glass fiber formation were studied utilizing NASA's KC-135 aircraft. Gravity was found to play a major role in final fiber diameter.

Tucker, D. S.↗
NASA NTRS2014

Early Results from the Lunar Atmosphere and Dust Environment Explorer (LADEE)

On 6 September, 2013, a near-perfect launch of the first Minotaur V rocket successfully carried NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) into a high-eccentricity geocentric orbit. After 30 days of phasing, LADEE arrived at the Moon on 6 October, 2013. LADEE's science objectives are twofold: (1) Determine the composition of the lunar atmosphere, investigate processes controlling its distribution and variability, including sources, sinks, and surface interactions; (2) Characterize the lunar exospheric dust environment, measure its spatial and temporal variability, and effects on the lunar atmosphere, if any. After a successful commissioning phase, the three science instruments have made systematic observations of the lunar dust and exospheric environment. These include initial observations of argon, neon and helium exospheres, and their diurnal variations; the lunar micrometeoroid impact ejecta cloud and its variations; spatial and temporal variations of the sodium exosphere; and the search for sunlight extinction caused by dust. LADEE also made observations of the effects of the Chang'e 3 landing on 14 December 2013.

lunar exospheric environment↗
NASA NTRS2016

An Examination of LADEE UVS Spectral Variability Associated with the Geminid Meteor Shower

The Lunar Atmosphere and Dust Environment Explorer (LADEE) was an orbital lunar science mission designed to address the goals of the 2003 National Research Council decadal survey, the Lunar Exploration Analysis Group Roadmap, and the “Scientific Context for Exploration of the Moon” (SCEM) report, and has been recommended for execution by the 2011 Planetary Missions Decadal Survey. The LADEE mission goal was to determine the composition of the lunar atmosphere and investigate the processes that control its distribution and variability, including sources, sinks, and surface interactions. LADEE monitored variations in known gasses, such as sodium, potassium, argon and helium, and searched for other, as-yet-undetected gasses of both lunar and extralunar origin. LADEE also examined whether dust is present in the lunar exosphere, and revealed the processes that contribute to its sources and variability. LADEE launched September 6, 2013, entered lunar orbit on October 6, 2013 and operated until April 17, 2014. Examined here are spectral variability at around the time of the Geminid meteor shower (at around December 13-14, 2014). UVS made standard limb observations at the Sunrise and Sunset terminators, as well as observation looking anti-sun on the dark side of the moon (the so called “Sodium-Tail” observation type). The before, during and after spectra are compared to look for variability in line emissions.

Ultraviolet and Visible Spectrometer (UVS)↗
NASA NTRS1976

The relation of metal composition to rock type for clasts in Apollo 16 soils

The moderately magnetic fractions of soils from a bright ray of South Ray Crater and from the continuous ejecta of North Ray Crater are described. The clasts in these fractions are classified as agglutinate, ANT melt rocks, glassy melt rocks, and ANT hornfels/breccia. Determinations are made of the Ni-Co and P contents of single-phase metal grains in the clasts. It is found that most of these grains have compositions in the meteoritic range and that the compositions tend to cluster at about 6% Ni. A significant amount of Fe-rich metal is also detected in some clasts along with a clear P-enrichment in metal from one soil sample. Meteoritic contamination of lunar metal having compositions in or close to the meteoritic range is considered. A model involving nine separate factors is proposed as an explanation of the observed metal compositions.

Hewins, R. H.↗
NASA NTRSDate not supplied

Influence of the Space Environment on Geopolymer Lunar Concrete

NASA is set to embark on the next era of human space exploration on the Artemis program. An eventual goal of the program is to maintain a human presence on the lunar surface. With such a goal comes the challenge of providing durable infrastructure that is suitable for the Moon and utilizes in-situ resources. Bringing materials form Earth poses a financial burden and increased safety concern. The composition of the lunar soil makes it advantageous to create a geopolymer concrete material. The lunar regolith can be used in the as found condition on the lunar surface and most of the mixing solution can be extracted form the regolith. It is envisioned than any concrete infrastructure would make use of additive manufacturing techniques with a temporary controlled environment enclosure to mitigate the harsh lunar conditions. Data is needed to benchmark how the material behaves once exposed to such an extreme environment so structural failures are mitigated.

Peter J. Collins↗
NASA NTRS2012

Predicting the Sources and Formation Mechanisms of Evolved Lunar Crust by Linking K/Ca Ratios of Lunar Granites to Analogous Terrestrial Igneous Rocks

Although silicic rocks (i.e. granites and rhyolites) comprise a minor component of the sampled portion of the lunar crust, recent remote sensing studies [e.g., 1-4] indicate that several un-sampled regions of the Moon have significantly higher concentrations of silicic material (also high in [K], [U], and [Th]) than sampled regions. Within these areas are morphological features that are best explained by the existence of chemically evolved volcanic rocks. Observations of silicic domes [e.g., 1-5] suggest that sizable networks of silicic melt were present during crust formation. Isotopic data indicate that silicic melts were generated over a prolonged timespan from 4.3 to 3.9 Ga [e.g., 6-8]. The protracted age range and broad distribution of silicic rocks on the Moon indicate that their petrogenesis was an important mechanism for secondary crust formation. Understanding the origin and evolution of such silicic magmas is critical to determining the composition of the lunar crustal highlands and will help to distinguish between opposing ideas for the Moon's bulk composition and differentiation. The two main hypotheses for generating silicic melts on Earth are fractional crystallization or partial melting. On the Moon silicic melts are thought to have been generated during extreme fractional crystallization involving end-stage silicate liquid immiscibility (SLI) [e.g. 9, 10]. However, SLI cannot account for the production of significant volumes of silicic melt and its wide distribution, as reported by the remote global surveys [1, 2, 3]. In addition, experimental and natural products of SLI show that U and Th, which are abundant in the lunar granites and seen in the remote sensing data of the domes, are preferentially partitioned into the depolymerized ferrobasaltic magma and not the silicic portion [11, 12]. If SLI is not the mechanism that generated silicic magmas on the Moon then alternative processes such as fractional crystallization (only crystal-liquid separation) or partial melting should be considered as viable possibilities to be tested.

Mills, R. D.↗
NASA NTRS1993

Gamma ray spectrometer for Lunar Scout 2

We review the current status of the Los Alamos program to develop a high-resolution gamma-ray spectrometer for the Lunar Scout-II mission, which is the second of two Space Exploration Initiative robotic precursor missions to study the Moon. This instrument will measure gamma rays in the energy range of approximately 0.1 - 10 MeV to determine the composition of the lunar surface. The instrument is a high-purity germanium crystal surrounded by an CsI anticoincidence shield and cooled by a split Stirling cycle cryocooler. It will provide the abundance of many elements over the entire lunar surface.

Moss, C. E.↗
NASA NTRS2002

Predictions for Radiation Shielding Materials

Radiation from galactic cosmic rays (GCR) and solar particle events (SPE) is a serious hazard to humans and electronic instruments during space travel, particularly on prolonged missions outside the Earth s magnetic fields. Galactic cosmic radiation (GCR) is composed of approx. 98% nucleons and approx. 2% electrons and positrons. Although cosmic ray heavy ions are 1-2% of the fluence, these energetic heavy nuclei (HZE) contribute 50% of the long-term dose. These unusually high specific ionizations pose a significant health hazard acting as carcinogens and also causing microelectronics damage inside spacecraft and high-flying aircraft. These HZE ions are of concern for radiation protection and radiation shielding technology, because gross rearrangements and mutations and deletions in DNA are expected. Calculations have shown that HZE particles have a strong preference for interaction with light nuclei. The best shield for this radiation would be liquid hydrogen, which is totally impractical. For this reason, hydrogen-containing polymers make the most effective practical shields. Shielding is required during missions in Earth orbit and possibly for frequent flying at high altitude because of the broad GCR spectrum and during a passage into deep space and LunarMars habitation because of the protracted exposure encountered on a long space mission. An additional hazard comes from solar particle events (SPEs) which are mostly energetic protons that can produce heavy ion secondaries as well as neutrons in materials. These events occur at unpredictable times and can deliver a potentially lethal dose within several hours to an unshielded human. Radiation protection for humans requires safety in short-term missions and maintaining career exposure limits within acceptable levels on future long-term exploration missions. The selection of shield materials can alter the protection of humans by an order of magnitude. If improperly selected, shielding materials can actually increase radiation damage due to penetration properties and nuclear fragmentation. Protecting space-borne microelectronics from single event upsets (SEUs) by transmitted radiation will benefit system reliability and system design cost by using optimal shield materials. Long-term missions on the surface of the Moon or Mars will require the construction of habitats to protect humans during their stay. One approach to the construction is to make structural materials from lunar or Martian regolith using a polymeric material as a binder. The hydrogen-containing polymers are considerably more effective for radiation protection than the regolith, but the combination minimizes the amount of polymer to be transported. We have made composites of simulated lunar regolith with two different polymers, LaRC-SI, a high-performance polyimide thermoset, and polyethylene, a thermoplastic.

Kiefer, Richard L.↗
NASA NTRS1977

Lunar elemental analysis obtained from the Apollo gamma-ray and X-ray remote sensing experiment

Gamma-ray and X-ray spectrometers carried in the service modules of the Apollo 15 and Apollo 16 spacecraft were employed for compositional mapping of the lunar surface. The measurements involved the observation of the intensity and characteristic energy distribution of gamma rays and X-rays emitted from the lunar surface. A large-scale compositional map of over 10 percent of the lunar surface was obtained from an analysis of the observed spectra. The objective of the X-ray experiment was to measure the K spectral lines from Mg, Al, and Si. Spectra were obtained and the data were reduced to Al/Si and Mg/Si intensity ratios and ultimately to chemical ratios. Analyses of the results have indicated (1) that the Al/Si ratios are highest in the lunar highlands and considerably lower in the maria, and (2) that the Mg/Si concentrations generally show the opposite relationship. The objective of the gamma-ray experiment was to measure the natural and cosmic-ray-induced activity emission spectrum. At this time, the elemental abundances for Th, U, K, Fe, Ti, Si, and O have been determined over a number of major lunar regions. Regions of relatively high natural radioactivity were found in the Mare Imbrium and Oceanus Procellarum regions.

Trombka, J. I.↗