Sample records for regolith

  1. The Role of Breccia Lenses in Regolith Generation From the Formation of Small, Simple Craters: Application to the Apollo 15 Landing Site

    NASA Astrophysics Data System (ADS)

    Hirabayashi, M.; Howl, B. A.; Fassett, C. I.; Soderblom, J. M.; Minton, D. A.; Melosh, H. J.

    2018-02-01

    Impact cratering is likely a primary agent of regolith generation on airless bodies. Regolith production via impact cratering has long been a key topic of study since the Apollo era. The evolution of regolith due to impact cratering, however, is not well understood. A better formulation is needed to help quantify the formation mechanism and timescale of regolith evolution. Here we propose an analytically derived stochastic model that describes the evolution of regolith generated by small, simple craters. We account for ejecta blanketing as well as regolith infilling of the transient crater cavity. Our results show that the regolith infilling plays a key role in producing regolith. Our model demonstrates that because of the stochastic nature of impact cratering, the regolith thickness varies laterally, which is consistent with earlier work. We apply this analytical model to the regolith evolution at the Apollo 15 site. The regolith thickness is computed considering the observed crater size-frequency distribution of small, simple lunar craters (< 381 m in radius for ejecta blanketing and <100 m in radius for the regolith infilling). Allowing for some amount of regolith coming from the outside of the area, our result is consistent with an empirical result from the Apollo 15 seismic experiment. Finally, we find that the timescale of regolith growth is longer than that of crater equilibrium, implying that even if crater equilibrium is observed on a cratered surface, it is likely that the regolith thickness is still evolving due to additional impact craters.

  2. Analysis of Lunar Highland Regolith Samples From Apollo 16 Drive Core 64001/2 and Lunar Regolith Simulants - an Expanding Comparative Database

    NASA Technical Reports Server (NTRS)

    Schrader, Christian M.; Rickman, Doug; Stoeser, Douglas; Wentworth, Susan; McKay, Dave S.; Botha, Pieter; Butcher, Alan R.; Horsch, Hanna E.; Benedictus, Aukje; Gottlieb, Paul

    2008-01-01

    This slide presentation reviews the work to analyze the lunar highland regolith samples that came from the Apollo 16 core sample 64001/2 and simulants of lunar regolith, and build a comparative database. The work is part of a larger effort to compile an internally consistent database on lunar regolith (Apollo Samples) and lunar regolith simulants. This is in support of a future lunar outpost. The work is to characterize existing lunar regolith and simulants in terms of particle type, particle size distribution, particle shape distribution, bulk density, and other compositional characteristics, and to evaluate the regolith simulants by the same properties in comparison to the Apollo sample lunar regolith.

  3. Going Steady: Using multiple isotopes to test the steady-state assumption at the Susquehanna Shale Hills Critical Zone Observatory (Invited)

    NASA Astrophysics Data System (ADS)

    West, N.; Kirby, E.; Ma, L.; Bierman, P. R.

    2013-12-01

    Regolith-mantled hillslopes are ubiquitous features of most temperate landscapes, and their morphology reflects the climatically, biologically, and tectonically mediated interplay between regolith production and downslope transport. Despite intensive research, few studies have quantified both of these mass fluxes in the same field site. Here, we exploit two isotopic systems to quantify regolith production and transport within the Susquehanna Shale Hills Critical Zone Observatory (SSHO), in central Pennsylvania. We present an analysis of 131 meteoric 10Be measurements from regolith and bedrock to quantify rates of regolith transport, and compare these data with previously determined regolith production rates, measured using uranium-series isotopes. Regolith flux inferred from meteoric 10Be varies linearly with topographic gradient (determined from high-resolution LiDAR-based topography) along the upper portions of hillslopes in and adjacent to SSHO. However, regolith flux appears to depend on the product of gradient and regolith depth where regolith is thick, near the base of hillslopes. Meteoric 10Be inventories along 4 ridgetops within and adjacent to the SSHO indicate regolith residence times ranging from ~ 9 - 15 ky, similar to residence times inferred from U-series isotopes (6.7 × 3 ky - 15 × 8 ky). Similarly, the downslope flux of regolith (~ 500 - 1,000 m2/My) nearly balances production (850 × 22 m2/My - 960 × 530 m2/My). The combination of our results with U-series derived regolith production rates implies that regolith production and erosion rates along ridgecrests in the SSHO may be approaching steady state conditions over the Holocene.

  4. Counterflow Regolith Heat Exchanger

    NASA Technical Reports Server (NTRS)

    Zubrin, Robert; Jonscher, Peter

    2013-01-01

    A problem exists in reducing the total heating power required to extract oxygen from lunar regolith. All such processes require heating a great deal of soil, and the heat energy is wasted if it cannot be recycled from processed material back into new material. The counterflow regolith heat exchanger (CoRHE) is a device that transfers heat from hot regolith to cold regolith. The CoRHE is essentially a tube-in-tube heat exchanger with internal and external augers attached to the inner rotating tube to move the regolith. Hot regolith in the outer tube is moved in one direction by a right-hand - ed auger, and the cool regolith in the inner tube is moved in the opposite direction by a left-handed auger attached to the inside of the rotating tube. In this counterflow arrangement, a large fraction of the heat from the expended regolith is transferred to the new regolith. The spent regolith leaves the heat exchanger close to the temperature of the cold new regolith, and the new regolith is pre-heated close to the initial temperature of the spent regolith. Using the CoRHE can reduce the heating requirement of a lunar ISRU system by 80%, reducing the total power consumption by a factor of two. The unique feature of this system is that it allows for counterflow heat exchange to occur between solids, instead of liquids or gases, as is commonly done. In addition, in variants of this concept, the hydrogen reduction can be made to occur within the counterflow heat exchanger itself, enabling a simplified lunar ISRU (in situ resource utilization) system with excellent energy economy and continuous nonbatch mode operation.

  5. Constraining Regolith Production on a Hillslope Over Long Timescales: Interpreting In Situ 10Be Concentrations on an Evolving Landscape

    NASA Astrophysics Data System (ADS)

    Foster, M. A.; Anderson, R. S.; Duehnforth, M.; Kelly, P. J.

    2011-12-01

    In situ produced 10Be cosmogenic radionuclide (CRN) concentrations provide geomorphologists with a quantitative tool to calculate regolith production rates in a variety of landscapes. However, the power of CRN dating is limited by the care with which these hard-earned numbers are interpreted. As rock is exhumed through the weathered zone, it accumulates in situ produced CRNs. Most studies assume a steady-state condition to calculate regolith production rates from 10Be concentrations obtained from rock at the base of mobile regolith; ignoring decay, the regolith production rate becomes simply Poe-H/z*/[10Be]. Although the balance of regolith production and the spatial pattern of divergence required to maintain steady regolith thickness is valid in some landscapes, steady-state is unlikely on hillslopes where time scales for generating soils are longer than climatic cycles. We report in situ 10Be concentrations to calculate production rates for mobile regolith in 8 soil pits along north- and south-facing slopes in Gordon Gulch, an intensively studied catchment in the Boulder Creek CZO. Gordon Gulch hillslopes exhibit variable regolith and saprolite thicknesses over gneissic and granitic parent rock; mean regolith thickness is 0.65 m. Local denudation rates in nearby catchments are 25 ± 8 m/Ma (Dethier and Lazarus, 2006). The mean residence time of mobile regolith in Gordon Gulch catchment is therefore 20-45 ka; less than half of this time is spent in Holocene climatic conditions. Although Gordon Gulch presently has mean annual temperature (MAT) ~4°C, it was likely at least 6°C cooler during the Last Glacial Maximum, meaning that periglacial conditions likely dominated. We therefore anticipate that parent rock could be more rapidly damaged by increased frost-cracking, and regolith transport be enhanced by increased frost-heave; thus steady-state conditions cannot be assumed over this timescale. To develop strategies for interpretation of 10Be, we employ a 1D numerical hillslope model in which regolith thickness and 10Be concentration are tracked at all hillslope positions. 10Be concentration in rock immediately subjacent to the regolith is updated both by decay and by production at a rate governed by the instantaneous regolith thickness (e.g. Riggins et al., 2011). Vertically averaged 10Be concentration in the regolith is updated by vertically averaged production rate, decay, addition from rock released at the base of the regolith, and advection of regolith. The resulting field of 10Be in bedrock at the regolith interface, from which one deduces long term average regolith production rates, varies both in time and in space. Our model indicates that regolith thickness fluctuates by tens of percent from the average condition over the timescale of glacial-interglacial cycles. The resulting shifts in 10Be concentrations at the base of regolith are of similar magnitude, with greater shifts of 10Be concentrations in regolith. We will employ this model tuned to the Gordon Gulch sites to interpret measured 10Be concentrations.

  6. Luna 24 regolith breccias: A possible source of the fine size material of the Luna 24 regolith

    NASA Technical Reports Server (NTRS)

    Rode, O. D.; Lindstrom, M. M.

    1994-01-01

    The regolith breccias from the Luna 24 core were analyzed. The Luna 24 regolith is a mixture of fine and coarse grain materials. The comparable analysis of the grain size distributions, the modal and chemical compositions of the breccias, and the regolith from the same levels show that the friable slightly litificated breccia with a friable fine grain matrix may be a source of fine grain material of the Luna 24 present day regolith.

  7. [Possibility of exacerbation of allergy by lunar regolith].

    PubMed

    Horie, Masanori; Kambara, Tatsunori; Kuroda, Etsushi; Miki, Takeo; Honma, Yoshiyuki; Aoki, Shigeru; Morimoto, Yasuo

    2012-09-01

    Japan, U.S.A. and other foreign space agencies have plans for the construction of a lunar base and long-term stay of astronauts on the moon. The surface of the moon is covered by a thick layer of soil that includes fine particles called "lunar regolith", which is formed by meteorite impact and space weathering. Risk assessment of particulate matter on the moon is important for astronauts working in microgravity on the moon. However, there are few investigations about the biological influences of lunar regolith. Especially, there is no investigation about allergic activity to lunar regolith. The main chemical components of lunar regolith are SiO2, Al2O3, CaO, FeO, etc. Of particular interest, approximately 50% of lunar regolith consists of SiO2. There is a report that the astronauts felt hay fever-like symptoms from the inhalation of the lunar regolith. Yellow sand, whose chemical components are similar to lunar regolith, enhances allergenic reactions, suggesting the possibility that lunar regolith has an adjuvant-like activity. Although intraperitoneal administration of lunar regolith with ovalbumin to mouse did not show enhancement of allergenic reactions, further evaluation of lunar regolith's potential to exacerbate the effects of allergies is essential for development of the moon.

  8. A potpourrie of regolith breccias: ``New'' samples from the Apollo 14, 16, and 17 landing sites

    NASA Astrophysics Data System (ADS)

    Jerde, Eric A.; Warren, Paul H.; Morris, Richard V.; Heiken, Grant H.; Vaniman, David T.

    1987-09-01

    Forty suspected regolith breccias from the Apollo 14, 16, and 17 landing sites were studied as part of a search for regolith samples exotic to the small traverse areas associated with these missions, as well as a general effort to constrain the nature and origins of regolith breccias. Of these 40 samples, 31 are indeed regolith breccias. Regolith breccias from Apollo 14 exhibit much greater compositional diversity than their soil (sensu stricto) counterparts: 14004,55 displays incompatible element concentrations about 1.4× those found in typical Apollo 14 regolith, while 14315 is radically different in many respects (higher Al, lower Mg and Fe, lower incompatible elements) from all other Apollo 14 regolith materials, and hence probably exotic to the Apollo 14 traverse area. Application of ``mixing'' models to Apollo 14 regolith materials suggests that whereas ``normal'' Apollo 14 regolith contains only slightly more ferroan anorthosite (FA) than alkali anorthosite (AA) and far more KREEP than FA and AA combined, 14315 contains more FA than KREEP and roughly 10 times more FA than AA. Three ``new'' regolith breccias from Apollo 16 bring to 20 the total number of regolith breccias that have been analyzed for Mg and Fe from the site. The molar Mg/)Mg+Fe) (or mg*) ratios of lunar regolith breccias are of great interest, because lunar meteorite ALH81005 has a much higher mg* than two other lunar meteoritic regolith breccias (Y791197 and Y82192/3), even though these three samples are remarkably similar in all other compositional respects. A bimodality in mg* among Apollo 16 regolith breccias may result from: (1) statistical scattering among the small number of samples, (2) a tendency for older regolith breccias from this site to be compositionally distinct form their younger counterparts, or (3) differences between the Cayley and Descartes Formations. Among 10 samples from Apollo 17, all but one proved to be typical Apollo 17 regolith breccias. However, 72504,10 is >99% pure pyroclastic glass, compositionally identical to the Apollo 1 orange galss (74220), even though 72504,10 was obtained at a location over 4 km from Shorty Crater where 74220 was obtained. The nearly pure concentration of 74220-identical glass spherules in 72504-10 attests to the widespread distribution of these distinctive deposits.

  9. Characterization of Apollo Regolith by X-Ray and Electron Microbeam Techniques: An Analog for Future Sample Return Missions

    NASA Technical Reports Server (NTRS)

    Zeigler, Ryan A.

    2015-01-01

    The Apollo missions collected 382 kg of rock and regolith from the Moon; approximately 1/3 of the sample mass collected was regolith. Lunar regolith consists of well mixed rocks, minerals, and glasses less than 1-centimeter n size. The majority of most surface regolith samples were sieved into less than 1, 1-2, 2-4, and 4-10- millimiter size fractions; a portion of most samples was re-served unsieved. The initial characterization and classification of most Apollo regolith particles was done primarily by binocular microscopy. Optical classification of regolith is difficult because (1) the finest fraction of the regolith coats and obscures the textures of the larger particles, and (b) not all lithologies or minerals are uniquely identifiable optically. In recent years, we have begun to use more modern x-ray beam techniques [1-3], coupled with high resolution 3D optical imaging techniques [4] to characterize Apollo and meteorite samples as part of the curation process. These techniques, particularly in concert with SEM imaging of less than 1-millimeter regolith grain mounts, allow for the rapid characterization of the components within a regolith.

  10. Effect of Metamorphic Foliation on Regolith Thickness, Catalina Critical Zone Observatory, Arizona

    NASA Astrophysics Data System (ADS)

    Leone, J. D.; Holbrook, W. S.; Chorover, J.; Carr, B.

    2016-12-01

    Terrestrial life is sustained by nutrients and water held in soil and weathered rock, which are components of the Earth's critical zone, referred to as regolith. The thickness of regolith in the near-surface is thought to be influenced by factors such as climate, topographic stress, erosion and lithology. Our study has two aims: to determine the effect of metamorphic foliation on regolith thickness and to test an environmental model, Effective Energy Mass Transfer (EEMT), within a zero-order basin (ZOB) in the Santa Catalina Mountains. Seismic refraction and electrical resistivity data show a stark contrast in physical properties, and inferred regolith thickness, on north- versus south-facing slopes: north-facing slopes are characterized by higher seismic velocities and higher resistivities, consistent with thin regolith, while south-facing slopes show lower resistivities and velocities, indicative of deeper and more extensive weathering. This contrast is exactly the opposite of that expected from most climatic models, including the EEMT model, which predicts deeper regolith on north-facing slopes. Instead, regolith thickness appears to be controlled by metamorphic foliation: we observed a general, positive correlation between interpreted regolith thickness and foliation dip within heavily foliated lithologies and no correlation in weakly foliated lithologies. We hypothesize that hydraulic conductivity controls weathering here: where foliation is parallel to the surface topography, regolith is thin, but where foliation pierces the surface topography at a substantial angle, regolith is thick. The effect of foliation is much larger than that expected from environmental models: regolith thickness varies by a factor of 4 (2.5 m vs. 10 m). These results suggest that metamorphic foliation, and perhaps by extension sedimentary layering, plays a key role in determining regolith thickness and must be accounted for in models of critical zone development.

  11. Formation Ages of the Apollo 16 Regolith Breccias: Implications for Accessing the Bombardment History of the Moon

    NASA Technical Reports Server (NTRS)

    Joy, K. H.; Kring, D. A.; Bogard, D. D.; Zolensky, M. E.; McKay, D. S.

    2010-01-01

    Regolith breccias are lithified samples of the regolith that have been fused together by impact shock and thermal metamorphism. In lunar regolith samples, the ratio of trapped 40Ar/36Ar is a useful indicator of antiquity and can be used to model the closure age/lifithication event of the regolith (i.e. the apparent time when Ar became trapped [1]), thus providing an important insight into specific times when that regolith was interacting with the the dynamic inner solar system space environment [2-4].

  12. Workshop on Past and Present Solar Radiation: The Record in Meteoritic and Lunar Regolith Material

    NASA Technical Reports Server (NTRS)

    Pepin, R. O. (Compiler); Mckay, D. S. (Compiler)

    1986-01-01

    The principal question addressed in the workshop was the extent to which asteroidal and lunar regoliths have collected and preserved, in meteoritic regolith breccias and in lunar soils and regolith breccias, a record of the flux, energy, and compositional history of the solar wind and solar flares. Six central discussion topics were identified. They are: (1)Trapped solar wind and flare gases, tracks, and micrometeorite pits in regolith components; (2)Comparison between lunar regolith breccias, meteoritic regolith breccias, and the lunar soil; (3)The special role of regolith breccias and the challenge of dating their times of compaction; (4)Implications of the data for the flux and compositional history of solar particle emission, composition, and physical mechanisms in the solar source regions, and the composition of the early nebula; (5)How and to what extent have records of incident radiation been altered in various types of grains; (6)Future research directions

  13. Mining for helium: Site selection and evaluation

    NASA Technical Reports Server (NTRS)

    Cameron, Eugene N.

    1988-01-01

    Part of the University of Wisconsin study of the feasibility of recovering He-3 from the moon is selection and evaluation of potential mining sites. Selection and evaluation are based primarily on salient findings by investigators: (1) Regoliths from areas underlain by highland materials contain less than 20 wppm He; (2) Regoliths of certain maria or parts of maria also contain less than 20 wppm He, but mare regoliths at the Apollo 11 and 17 sites contain 25 to 49 wppm He; (3) The helium content of a regolith is a function of its composition; and (4) Helium is concentrated in the -50 micron size fractions of regoliths. In site selection, the concern is with the compositions of lunar regoliths, in particular with their titanium contents. It is widely accepted that compositions of mare regoliths are controlled by the nature of the underlying basalts from which the regoliths are largely derived. The distribution and extent of the three groups of basalts and the regoliths derived from them are the first basis for site selection and evaluation. Other considerations are briefly discussed.

  14. Grain rims on ilmenite in the lunar regolith: Comparison to vapor deposits on regolith silicates

    NASA Technical Reports Server (NTRS)

    Christoffersen, R.; Mckay, D. S.; Keller, L. P.

    1994-01-01

    In efforts to understand regolith evolution on airless bodies, increasing attention is now being payed to those processes and events that alter or 'weather' the surfaces of regolith grains. This attention has developed partly out of the ongoing need to optimize models of planetary reflectance spectra and the growing recognition that diverse types of grain coatings and surface alterations occur which can strongly influence mineral reflectance properties. In addition to their implications for optical properties, surface features on regolith grains have provided useful clues to the basic thermal, chemical, and radiation history of regoliths.

  15. Extant and Extinct Lunar Regolith Simulants: Modal Analyses of NU-LHT-1M and -2m, OB-1, JSC-1, JSC-1A and -1AF,FJS-1, and MLS-1

    NASA Technical Reports Server (NTRS)

    Schrader, Christian; Rickman, Doug; McLemore, Carole; Fikes, John; Wilson, Stephen; Stoeser, Doug; Butcher, Alan; Botha, Pieter

    2008-01-01

    This work is part of a larger effort to compile an internally consistent database on lunar regolith (Apollo samples) and lunar regolith simulants. Characterize existing lunar regolith and simulants in terms of: a) Particle type; b) Particle size distribution; c) Particle shape distribution; d) Bulk density; and e) Other compositional characteristics. Evaluate regolith simulants (Figure of Merit) by above properties by comparison to lunar regolith (Apollo sample) This presentation covers new data on lunar simulants.

  16. Impact cratering and regolith dynamics. [on moon

    NASA Technical Reports Server (NTRS)

    Hoerz, F.

    1977-01-01

    The most recent models concerning mechanical aspects of lunar regolith dynamics related to impact cratering use probabilistic approaches to account for the randomness of the meteorite environment in both space and time. Accordingly the absolute regolith thickness is strictly a function of total bombardment intensity and absolute regolith growth rate in nonlinear through geologic time. Regoliths of increasing median thickness will have larger and larger proportions of more and more deep seated materials. An especially active zone of reworking on the lunar surface of about 1 mm depth has been established. With increasing depth, the probability of excavation and regolith turnover decreases very rapidly. Thus small scale stratigraphy - observable in lunar core materials - is perfectly compatible with regolith gardening, though it is also demonstrated that any such stratigraphy does not necessarily present a complete record of the regolith's depositional history. At present, the lifetimes of exposed lunar rocks against comminution by impact processes can be modeled; it appears that catastrophic rupture dominates over single particle abrasion.

  17. Where fast weathering creates thin regolith and slow weathering creates thick regolith

    USGS Publications Warehouse

    Bazilevskaya, Ekaterina; Lebedeva, Marina; Pavich, Milan J.; Brantley, Susan L.; Rother, Gernot; Parkinson, Dilworth Y.; Cole, David

    2013-01-01

    Weathering disaggregates rock into regolith – the fractured or granular earth material that sustains life on the continental land surface. Here, we investigate what controls the depth of regolith formed on ridges of two rock compositions with similar initial porosities in Virginia (USA). A priori, we predicted that the regolith on diabase would be thicker than on granite because the dominant mineral (feldspar) in the diabase weathers faster than its granitic counterpart. However, weathering advanced 20 deeper into the granite than the diabase. The 20 -thicker regolith is attributed mainly to connected micron-sized pores, microfractures formed around oxidizing biotite at 20 m depth, and the lower iron (Fe) content in the felsic rock. Such porosity allows pervasive advection and deep oxidation in the granite. These observations may explain why regolith worldwide is thicker on felsic compared to mafic rock under similar conditions. To understand regolith formation will require better understanding of such deep oxidation reactions and how they impact fluid flow during weathering.

  18. Regolith on Super Fast Rotators

    NASA Astrophysics Data System (ADS)

    Sanchez Lana, Diego Paul; Scheeres, Daniel J.

    2017-10-01

    The current understanding of small asteroids in the Solar System is that they are gravitational aggregates held together by gravitational, cohesive and adhesive forces. Results from the Hayabusa mission to Itokawa along with in situ, thermal and radar observations of asteroids have shown that they can be covered in a size distribution of grains that spans from microns to tens of meters. Before the Hayabusa mission, it was generally thought that smaller asteroids would likely be “regolith-free,” due to impact seismic shaking removing the loose covering. Given the regolith-rich surface of that body, it is now an open question whether even smaller bodies, down to a few meters in size, could also retain regolith covering. The question is especially compelling for the small-fast rotators, whose surface centripetal accelerations exceed their gravitational attraction. When the physical theory of cohesion is considered, it becomes possible for small-fast rotators to retain regolith.We use a Soft-Sphere discrete element method (SSDEM) code to simulate a longitudinal slice of a spherical monolith covered by cohesive regolith. The simulations are carried out in the body frame. Tensile strength is varied to span the observed strength of asteroids and spin rate is elevated in small steps until the majority of regolith is removed from the surface. The simulations show that under an increasing spin rate (such as due to the YORP effect), the regolith covering on an otherwise monolithic asteroid is preferentially lost across certain regions of the body. In general, regolith from the mid latitudes is the first to fail at high spin rates. This failure happens either by regolith flowing towards the equator or by detachment of large coherent chunks of material depending on the tensile strength of the regolith. Regolith from the equator region fails next, usually by the detachment of large pieces. Regolith from the poles stays in place unless the spin rates are extremely high. With these results we derive a scaling law that can be used to determine whether observed small asteroids could retain surface regolith of a given size. The implications of this for the interpretation of spectral observations of small asteroids are discussed.

  19. A drilling tool design and in situ identification of planetary regolith mechanical parameters

    NASA Astrophysics Data System (ADS)

    Zhang, Weiwei; Jiang, Shengyuan; Ji, Jie; Tang, Dewei

    2018-05-01

    The physical and mechanical properties as well as the heat flux of regolith are critical evidence in the study of planetary origin and evolution. Moreover, the mechanical properties of planetary regolith have great value for guiding future human planetary activities. For planetary subsurface exploration, an inchworm boring robot (IBR) has been proposed to penetrate the regolith, and the mechanical properties of the regolith are expected to be simultaneously investigated during the penetration process using the drilling tool on the IBR. This paper provides a preliminary study of an in situ method for measuring planetary regolith mechanical parameters using a drilling tool on a test bed. A conical-screw drilling tool was designed, and its drilling load characteristics were experimentally analyzed. Based on the drilling tool-regolith interaction model, two identification methods for determining the planetary regolith bearing and shearing parameters are proposed. The bearing and shearing parameters of lunar regolith simulant were successfully determined according to the pressure-sinkage tests and shear tests conducted on the test bed. The effects of the operating parameters on the identification results were also analyzed. The results indicate a feasible scheme for future planetary subsurface exploration.

  20. Unravelling regolith material types using Mg/Al and K/Al plot to support field regolith identification in the savannah regions of NW Ghana, West Africa

    NASA Astrophysics Data System (ADS)

    Arhin, Emmanuel; Zango, Saeed M.

    2015-12-01

    The XRF analytical method was used to measure the weight % of the major oxides in regolith samples. The metal weight % of Mg, K and Al were calculated from their oxides and were normalised relative to immobile Al calculated from its oxide. The plot of Mg/Al and K/Al identified the regolith of the study area to consist of 137 transported clays, 4 ferruginous sediments or ferricrete, 2 lateritic duricrust and 4 saprolites. Surface regolith that had undergone secondary transformation and shows compositional overlaps were 4 transported clays with Fe-oxide impregnation may be referred to as nodular laterite and 5 ferruginous saprolites. The variable regolith materials features identified from the 154 samples enabled the characterisation and identification of the different sample materials because an overprint of bedrock geochemistry is reflected in the regolith. Plot of Mg/Al and K/Al highlighted the compositional variability of the regolith samples and refute the notion of the homogeneity of all the sampled materials in the area. The study thus recognized Mg/Al versus K/Al plots to be used in supporting field identification of regolith mapping units particularly in complex regolith terrains of savannah regions of Ghana and in similar areas where geochemical exploration surveys are being carried out under cover.

  1. Evaluation of geophysical properties of the lunar regolith for the design of precursor scientific missions for the space exploration initiative

    NASA Technical Reports Server (NTRS)

    Morgan, Paul

    1990-01-01

    The following topics are addressed: (1) the frequency of encountering boulders that represent hazards to lunar operations; (2) the ease of lunar soil excavation; (3) the use of explosives in excavation operation; (4) the trafficability of the regolith; (5) problems encountered in mining (probably strip mining) of the regolith; (6) the stable angle(s) of repose in excavation of the regolith; (7) the layering to be encountered in the subsurface; (8) knowledge of the regolith site and the possibility of its general application to any site on the lunar surface; (9) the data needed to characterize a site for a lunar base; (10) the influence of regolith properties on the design of geophysical experiments from the lunar base; and (11) terrestrial analogues for the geophysical properties of the lunar regolith.

  2. Concentrations of Volatiles in the Lunar Regolith

    NASA Technical Reports Server (NTRS)

    Taylor, Jeff; Taylor, Larry; Duke, Mike

    2007-01-01

    To set lower and upper limits on the overall amounts and types of volatiles released during heating of polar regolith, we examined the data for equatorial lunar regolith and for the compositions of comets. The purpose, specifically, was to answer these questions: 1. Upper/Lower limits and 'best guess' for total amount of volatiles (by weight %) released from lunar regolith up to 150C 2. Upper/Lower limit and 'best guess' for composition of the volatiles released from the lunar regolith by weight %

  3. Asteroid Icy Regolith Excavation and Volatile Capture Project

    NASA Technical Reports Server (NTRS)

    Zeitlin, Nancy; Mantovani, James; Swanger, Adam; Townsend, Ivan

    2015-01-01

    Icy regolith simulants will be produced in a relevant vacuum environment using various minerals, including hydrated minerals, that are found in C-type meteorites and in other types of planetary regolith. This will allow us to characterize the mechanical strength of the icy regolith as a function of ice content using penetration, excavation, and sample capture devices. The results of this study will benefit engineers in designing efficient regolith excavators and ISRU processing systems for future exploration missions to asteroids and other planetary bodies.

  4. Regolith thermal energy storage for lunar nighttime power

    NASA Technical Reports Server (NTRS)

    Tillotson, Brian

    1992-01-01

    A scheme for providing nighttime electric power to a lunar base is described. This scheme stores thermal energy in a pile of regolith. Any such scheme must somehow improve on the poor thermal conductivity of lunar regolith in vacuum. Two previous schemes accomplish this by casting or melting the regolith. The scheme described here wraps the regolith in a gas-tight bag and introduces a light gas to enhance thermal conductivity. This allows the system to be assembled with less energy and equipment than schemes which require melting of regolith. A point design based on the new scheme is presented. Its mass from Earth compares favorably with the mass of a regenerative fuel cell of equal capacity.

  5. An investigation of the thermal shock resistance of lunar regolith and the recovery of hydrogen from lunar soil heated using microwave radiation

    NASA Technical Reports Server (NTRS)

    Meek, T. T.

    1991-01-01

    The objective is to develop a better understanding of the thermal shock properties of lunar regolith sintered using 2.45 GHz electromagnetic radiation and to do a preliminary study into the recovery of bound hydrogen in lunar soil heated using 2.45 GHz radiation. During the first phase of this work, lunar simulant material was used to test whether or not microhardness data could be used to infer thermal shock resistance and later actual lunar regolith was used. Results are included on the lunar regolith since this is of primary concern and not the simulant results. They were similar, however. The second phase investigated the recovery of hydrogen from lunar regolith and results indicate that microwave heating of lunar regolith may be a good method for recovery of bound gases in the regolith.

  6. Planetary Regolith Delivery Systems for ISRU

    NASA Technical Reports Server (NTRS)

    Mantovani, James G.; Townsend, Ivan I., III

    2012-01-01

    The challenges associated with collecting regolith on a planetary surface and delivering it to an in-situ resource utilization system differ significantly from similar activities conducted on Earth. Since system maintenance on a planetary body can be difficult or impossible to do, high reliability and service life are expected of a regolith delivery system. Mission costs impose upper limits on power and mass. The regolith delivery system must provide a leak-tight interface between the near-vacuum planetary surface and the pressurized ISRU system. Regolith delivery in amounts ranging from a few grams to tens of kilograms may be required. Finally, the spent regolith must be removed from the ISRU chamber and returned to the planetary environment via dust tolerant valves capable of operating and sealing over a large temperature range. This paper will describe pneumatic and auger regolith transfer systems that have already been field tested for ISRU, and discuss other systems that await future field testing.

  7. Field Testing of a Pneumatic Regolith Feed System During a 2010 ISRU Field Campaign on Mauna Kea, Hawaii

    NASA Technical Reports Server (NTRS)

    Craft, Jack; Zacny, Kris; Chu, Philip; Wilson, Jack; Santoro, Chris; Carlson, Lee; Maksymuk, Michael; Townsend, Ivan I.; Mueller, Robert P.; Mantovani, James G.

    2010-01-01

    Lunar In Situ Resource Utilization (ISRU) consists of a number of tasks starting with mining of lunar regolith, followed by the transfer of regolith to an oxygen extraction reactor and finally processing the regolith and storing of extracted oxygen. The transfer of regolith from the regolith hopper at the ground level to an oxygen extraction reactor many feet above the surface could be accomplished in different ways, including using a mechanical auger, bucket ladder system or a pneumatic system. The latter system is commonly used on earth when moving granular materials since it offers high reliability and simplicity of operation. In this paper, we describe a pneumatic regolith feed system, delivering feedstock to a Carbothermal reactor and lessons learned from deploying the system during the 2010 ISRU field campaign on the Mauna Kea, Hawaii.

  8. Mars - The regolith-atmosphere-cap system and climate change

    NASA Technical Reports Server (NTRS)

    Fanale, F. P.; Salvail, J. R.; Banerdt, W. B.; Saunders, R. S.

    1982-01-01

    A model is derived for the prediction of the Martian regolith-atmosphere-cap CO2 regime's behavior, as well as for the description of the roly of the regime in climate change, through descriptions of the time-temperature histories of 90 regolith 'chunks' on a latitude-depth grid. The influence of differences in regolith adsorption laws for basalt and clay, and the influence of variations in regolith depth with (1) latitude, (2) regolith thermal diffusivity, and (3) total exchangeable CO2 inventory on predicted variations in atmospheric pressure and cap mass, are examined. It is found that the atmosphere acts as a low capacity conduit between two reservoirs through which 10-100 times the current atmospheric mass of CO2 flows. The exchange between the reservoirs is driven by obliquity variations, with the polar cap the dominant CO2 sink at low obliquity and the regolith dominating at high obliquity.

  9. Lunar Resource Utilization: Development of a Reactor for Volatile Extraction from Regolith

    NASA Technical Reports Server (NTRS)

    Kleinhenz, Julie E.; Sacksteder, Kurt R.; Nayagam, Vedha

    2007-01-01

    The extraction and processing of planetary resources into useful products, known as In- Situ Resource Utilization (ISRU), will have a profound impact on the future of planetary exploration. One such effort is the RESOLVE (Regolith and Environment Science, Oxygen and Lunar Volatiles Extraction) Project, which aims to extract and quantify these resources. As part of the first Engineering Breadboard Unit, the Regolith Volatiles Characterization (RVC) reactor was designed and built at the NASA Glenn Research Center. By heating and agitating the lunar regolith, loosely bound volatiles, such as hydrogen and water, are released and stored in the reactor for later analysis and collection. Intended for operation on a robotic rover, the reactor features a lightweight, compact design, easy loading and unloading of the regolith, and uniform heating of the regolith by means of vibrofluidization. The reactor performance was demonstrated using regolith simulant, JSC1, with favorable results.

  10. The regolith portion of the lunar meteorite Sayh al Uhaymir 169

    NASA Astrophysics Data System (ADS)

    Al-Kathiri, A.; Gnos, E.; Hofmann, B. A.

    Sayh al Uhaymir (SaU) 169 is a composite lunar meteorite from Oman that consists of polymict regolith breccia (8.44 ppm Th), adhering to impact-melt breccia (IMB; 32.7 ppm Th). In this contribution we consider the regolith breccia portion of SaU 169, and demonstrate that it is composed of two generations representing two formation stages, labeled II and III. The regolith breccia also contains the following clasts: Ti-poor to Ti-rich basalts, gabbros to granulites, and incorporated regolith breccias. The average SaU 169 regolith breccia bulk composition lies within the range of Apollo 12 and 14 soil and regolith breccias, with the closest correspondence being with that of Apollo 14, but Sc contents indicate a higher portion of mare basalts. This is supported by relations between Sm-Al2O3, FeO-Cr2O3-TiO2, Sm/Eu and Th-K2O. The composition can best be modeled as a mixture of high-K KREEP, mare basalt and norite/troctolite, consistent with the rareness of anorthositic rocks. The largest KREEP breccia clast in the regolith is identical in its chemical composition and total REE content to the incompatible trace-element (ITE)- rich high-K KREEP rocks of the Apollo 14 landing site, pointing to a similar source. In contrast to Apollo 14 soil, SaU 169 IMB and SaU 169 KREEP breccia clast, the SaU 169 regolith is not depleted in K/Th, indicating a low contribution of high-Th IMB such as the SaU 169 main lithology in the regolith. The data presented here indicate the SaU 169 regolith breccia is from the lunar front side, and has a strong Procellarum KREEP Terrane signature.

  11. Additive Construction using Basalt Regolith Fines

    NASA Technical Reports Server (NTRS)

    Mueller, Robert P.; Sibille, Laurent; Hintze, Paul E.; Lippitt, Thomas C.; Mantovani, James G.; Nugent, Matthew W.; Townsend, Ivan I.

    2014-01-01

    Planetary surfaces are often covered in regolith (crushed rock), whose geologic origin is largely basalt. The lunar surface is made of small-particulate regolith and areas of boulders located in the vicinity of craters. Regolith composition also varies with location, reflecting the local bedrock geology and the nature and efficiency of the micrometeorite-impact processes. In the lowland mare areas (suitable for habitation), the regolith is composed of small granules (20 - 100 microns average size) of mare basalt and volcanic glass. Impacting micrometeorites may cause local melting, and the formation of larger glassy particles, and this regolith may contain 10-80% glass. Studies of lunar regolith are traditionally conducted with lunar regolith simulant (reconstructed soil with compositions patterned after the lunar samples returned by Apollo). The NASA Kennedy Space Center (KSC) Granular Mechanics & Regolith Operations (GMRO) lab has identified a low fidelity but economical geo-technical simulant designated as Black Point-1 (BP-1). It was found at the site of the Arizona Desert Research and Technology Studies (RATS) analog field test site at the Black Point lava flow in adjacent basalt quarry spoil mounds. This paper summarizes activities at KSC regarding the utilization of BP-1 basalt regolith and comparative work with lunar basalt simulant JSC-1A as a building material for robotic additive construction of large structures. In an effort to reduce the import or in-situ fabrication of binder additives, we focused this work on in-situ processing of regolith for construction in a single-step process after its excavation. High-temperature melting of regolith involves techniques used in glassmaking and casting (with melts of lower density and higher viscosity than those of metals), producing basaltic glass with high durability and low abrasive wear. Most Lunar simulants melt at temperatures above 1100 C, although melt processing of terrestrial regolith at 1500 C is not uncommon. These temperatures are achievable by laser heating or by using solar concentrators. Similar to volcanic magma, the cooling rate determines the crystallite size - slower cooling develops larger crystals, and rapid quenching can result in fully amorphous glass.

  12. Regolith thickness over Sinus Iridum: Results from morphology and size-frequency distribution of small impact craters

    NASA Astrophysics Data System (ADS)

    Fa, Wenzhe; Liu, Tiantian; Zhu, Meng-Hua; Haruyama, Junichi

    2014-08-01

    High-resolution optical images returned from recent lunar missions provide a new chance for estimation of lunar regolith thickness using morphology and the size-frequency distribution of small impact craters. In this study, regolith thickness over the Sinus Iridum region is estimated using Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Cameras (NACs) images. A revised relationship between crater geometry and regolith thickness is proposed based on old experimental data that takes into considering the effect of the illumination angle of the images. In total, 227 high-resolution LROC NAC images are used, and 378,556 impact craters with diameters from 4.2 to 249.8 m are counted, and their morphologies are identified. Our results show that 50% of the Sinus Iridum region has a regolith thickness between 5.1 and 10.7 m, and the mean and median regolith thicknesses are 8.5 and 8.0 m, respectively. There are substantial regional variations in the regolith thickness, with its median value varying from 2.6 to 12.0 m for most regions. Local variations of regolith thickness are found to be correlated with the lunar surface age: the older the surface, the greater the thickness. In addition, sporadically distributed impact ejecta and crater rays are associated with relatively larger regolith thickness, which might result from excavation and transport of materials during the formation of the secondaries of Copernican-aged craters. Our estimated regolith thickness can help with future analysis of Chang'E-3 lunar penetrating radar echoes and studies of the subsurface stratigraphic structure of the Moon.

  13. Analysis of Thermal and Reaction Times for Hydrogen Reduction of Lunar Regolith

    NASA Technical Reports Server (NTRS)

    Hegde, U.; Balasubramaniam, R.; Gokoglu, S.

    2008-01-01

    System analysis of oxygen production by hydrogen reduction of lunar regolith has shown the importance of the relative time scales for regolith heating and chemical reaction to overall performance. These values determine the sizing and power requirements of the system and also impact the number and operational phasing of reaction chambers. In this paper, a Nusselt number correlation analysis is performed to determine the heat transfer rates and regolith heat up times in a fluidized bed reactor heated by a central heating element (e.g., a resistively heated rod, or a solar concentrator heat pipe). A coupled chemical and transport model has also been developed for the chemical reduction of regolith by a continuous flow of hydrogen. The regolith conversion occurs on the surfaces of and within the regolith particles. Several important quantities are identified as a result of the above analyses. Reactor scale parameters include the void fraction (i.e., the fraction of the reactor volume not occupied by the regolith particles) and the residence time of hydrogen in the reactor. Particle scale quantities include the particle Reynolds number, the Archimedes number, and the time needed for hydrogen to diffuse into the pores of the regolith particles. The analysis is used to determine the heat up and reaction times and its application to NASA s oxygen production system modeling tool is noted.

  14. Analysis of Thermal and Reaction Times for Hydrogen Reduction of Lunar Regolith

    NASA Technical Reports Server (NTRS)

    Hegde, U.; Balasubramaniam, R.; Gokoglu, S.

    2009-01-01

    System analysis of oxygen production by hydrogen reduction of lunar regolith has shown the importance of the relative time scales for regolith heating and chemical reaction to overall performance. These values determine the sizing and power requirements of the system and also impact the number and operational phasing of reaction chambers. In this paper, a Nusselt number correlation analysis is performed to determine the heat transfer rates and regolith heat up times in a fluidized bed reactor heated by a central heating element (e.g., a resistively heated rod, or a solar concentrator heat pipe). A coupled chemical and transport model has also been developed for the chemical reduction of regolith by a continuous flow of hydrogen. The regolith conversion occurs on the surfaces of and within the regolith particles. Several important quantities are identified as a result of the above analyses. Reactor scale parameters include the void fraction (i.e., the fraction of the reactor volume not occupied by the regolith particles) and the residence time of hydrogen in the reactor. Particle scale quantities include the particle Reynolds number, the Archimedes number, and the time needed for hydrogen to diffuse into the pores of the regolith particles. The analysis is used to determine the heat up and reaction times and its application to NASA s oxygen production system modeling tool is noted.

  15. Analysis of lunar regolith thermal energy storage

    NASA Technical Reports Server (NTRS)

    Colozza, Anthony J.

    1991-01-01

    The concept of using lunar regolith as a thermal energy storage medium was evaluated. The concept was examined by mathematically modeling the absorption and transfer of heat by the lunar regolith. Regolith thermal and physical properties were established through various sources as functions of temperature. Two cases were considered: a semi-infinite, constant temperature, cylindrical heat source embedded in a continuum of lunar regolith and a spherically shaped molten zone of lunar regolith set with an initial temperature profile. The cylindrical analysis was performed in order to examine the amount of energy which can be stored in the regolith during the day. At night, the cylinder acted as a perfect insulator. This cycling was performed until a steady state situation was reached in the surrounding regolith. It was determined that a cycling steady state occurs after approximately 15 day/night cycles. Results were obtained for cylinders of various diameters. The spherical molten zone analysis was performed to establish the amount of thermal energy, within the regolith, necessary to maintain some molten material throughout a nighttime period. This surrounding temperature profile was modeled after the cycling steady state temperature profile established by the cylindrical analysis. It was determined that a molten sphere diameter of 4.76 m is needed to maintain a core temperature near the low end of the melting temperature range throughout one nighttime period.

  16. Development and Validation of a Model for Hydrogen Reduction of JSC-1A

    NASA Technical Reports Server (NTRS)

    Hegde, U.; Balasubramaniam, R.; Gokoglu, S.

    2009-01-01

    Hydrogen reduction of lunar regolith has been proposed as a viable technology for oxygen production on the moon. Hydrogen reduces FeO present in the lunar regolith to form metallic iron and water. The water may be electrolyzed to recycle the hydrogen and produce oxygen. Depending upon the regolith composition, FeO may be bound to TiO2 as ilmenite or it may be dispersed in glassy substrates. Some testing of hydrogen reduction has been conducted with Apollo-returned lunar regolith samples. However, due to the restricted amount of lunar material available for testing, detailed understanding and modeling of the reduction process in regolith have not yet been developed. As a step in this direction, hydrogen reduction studies have been carried out in more detail with lunar regolith simulants such as JSC-1A by NASA and other organizations. While JSC-1A has some similarities with lunar regolith, it does not duplicate the wide variety of regolith types on the moon, for example, it contains almost no ilmenite. Nonetheless, it is a good starting point for developing an understanding of the hydrogen reduction process with regolith-like material. In this paper, a model utilizing a shrinking core formulation coupled with the reactor flow is described and validated against experimental data on hydrogen reduction of JSC-1A.

  17. The 2010 Field Demonstration of the Solar Carbothermal Reduction of Regolith to Produce Oxygen

    NASA Technical Reports Server (NTRS)

    Muscatello, Anthony; Gustafson, Robert (Bob)

    2010-01-01

    This slide presentation reviews a demonstration of the use of solar carbothermal reduction processing of regolith to produce oxygen and silicon from silica. A contractor developed the Carbothermal Regolith Reduction Module to demonstrate the extraction of oxygen from lunar regolith simulant using concentrated solar energy at a site that has similar terrain to the moon and Mars.

  18. Implications of Geology for Construction

    NASA Technical Reports Server (NTRS)

    Rickman, Doug

    2009-01-01

    The surface of the Moon is covered in regolith, which is NOT soil! The regolith is shattered igneous rock plus glass. The particles are unsorted, unweathered and not abraided. Modeling of the regolith at the level of individual particles will be very problematic. Modeling of the regolith, if successful for one area, will be successful for most other areas if variation in particle size is addressed.

  19. The 2010 Field Demonstration of the Solar Carbothermal Reduction of Regolith to Produce Oxygen

    NASA Technical Reports Server (NTRS)

    Gustafson, R. J.; White, B. C.; Fidler, M. J.; Muscatello, Anthony C.

    2010-01-01

    The Moon and other space exploration destinations are comprised of a variety of oxygen-bearing minerals, providing a virtually unlimited quantity of raw material which can be processed to produce oxygen. One attractive method to extract oxygen from the regolith is the carbothermal reduction process, which is not sensitive to variations in the mineral composition of the regolith. It also creates other valuable resources within the processed regolith, such as iron and silicon metals. Using funding from NASA, ORBITEC recently built and tested the Carbothermal Regolith Reduction Module to process lunar regolith simulants using concentrated solar energy. This paper summarizes the experimental test results obtained during a demonstration of the system at a lunar analog test site on the Mauna Kea volcano on Hawaii in February 2010.

  20. Monte Carlo calculations of lunar regolith thickness distributions.

    NASA Technical Reports Server (NTRS)

    Oberbeck, V. R.; Quaide, W. L.; Mahan, M.; Paulson, J.

    1973-01-01

    It is pointed out that none of the existing models of lunar regolith evolution take into account the relationship between regolith thickness, crater shape, and volume of debris ejected. The results of a Monte Carlo computer simulation of regolith evolution are presented. The simulation was designed to consider the full effect of the buffering regolith through calculation of the amount of debris produced by any given crater as a function of the amount of debris present at the site of the crater at the time of crater formation. The method is essentially an improved version of the Oberbeck and Quaide (1968) model.

  1. Strong Evidence of Variable Micro-meteor Flux from Apollo 17 Samples Obtained at Shorty Crater and on the Light Mantle Avalanche at Taurus-Littrow

    NASA Astrophysics Data System (ADS)

    Schmitt, H. H.; Petro, N. E.

    2017-12-01

    Light-gray regolith overlying the orange and black pyroclastic ash (Schmitt, 2017) at Shorty Crater protected the ash from incorporation into surrounding basaltic regolith for 3.5 billion years (Tera and Wasserburg, 1976; Saito and Alexander, 1979). Inspection of LROC images indicate this regolith probably came from a 350 m diameter, degraded impact crater (Fitzgibbon Crater), about 1 km NNE of Shorty. This regolith was derived largely from basalt and spread over the ash deposit about 24 Myr (Eugster, et al., 1979, corrected for post-Shorty exposure) after the last ash eruption. Maturity indexes for light gray regolith samples 74441 and 74461 are about 8 (Morris, 1978) and agglutinate concentrations are 8% and 7.7% (Heiken and McKay, 1974), respectively. These values are inconsistent with the exposure and cycling of the light-gray regolith during 3.5 billion years in the lunar surface impact environment (i.e., the time between ash deposition and the light mantle avalanche). If agglutinate content and Is/FeO indexes largely reflect the cumulative effect of micro-meteor impacts, as generally concluded, the light-gray regolith formed in an environment with significantly less micro-meteor flux than that which has prevailed more recently. 14-18% of fragile, ropy glass in the light-gray regolith, as compared with <1% in presently exposed Taurus-Littrow regoliths, also is consistent with low micro-meteor flux during development. The high recent micro-meteor flux appears to have existed for at least for the last 75 million years (Schmitt, et al., 2017), the estimated time using LROC-based crater frequency analysis (van der Bogert, et al., 2012) since the light mantle avalanche of South Massif regolith covered the light-gray regolith. New regolith on the light mantle appears to be developing a higher concentration of agglutinates and a higher maturity index relative to regolith in deeper portions of the unit. Light mantle avalanche samples 73141 (subsurface) and 73121 (near surface), have agglutinates at 32% and 42% and Is/FeO indexes of 48 and 78, respectively. This difference further supports the hypothesis of a highly variable micro-meteor flux throughout lunar history, with its current flux being significantly higher than for some period both prior to and subsequent to 3.5 Ga.

  2. [Evaluation of Cellular Effects Caused by Lunar Regolith Simulant Including Fine Particles].

    PubMed

    Horie, Masanori; Miki, Takeo; Honma, Yoshiyuki; Aoki, Shigeru; Morimoto, Yasuo

    2015-06-01

    The National Aeronautics and Space Administration has announced a plan to establish a manned colony on the surface of the moon, and our country, Japan, has declared its participation. The surface of the moon is covered with soil called lunar regolith, which includes fine particles. It is possible that humans will inhale lunar regolith if it is brought into the spaceship. Therefore, an evaluation of the pulmonary effects caused by lunar regolith is important for exploration of the moon. In the present study, we examine the cellular effects of lunar regolith simulant, whose components are similar to those of lunar regolith. We focused on the chemical component and particle size in particular. The regolith simulant was fractionated to < 10 μm, < 25 μm and 10-25 μm by gravitational sedimentation in suspensions. We also examined the cellular effects of fine regolith simulant whose primary particle size is 5.10 μm. These regolith simulants were applied to human lung carcinoma A549 cells at concentrations of 0.1 and 1.0 mg/ml. Cytotoxicity, oxidative stress and immune response were examined after 24 h exposure. Cell membrane damage, mitochondrial dysfunction and induction of Interleukin-8 (IL-8) were observed at the concentration of 1.0 mg/ml. The cellular effects of the regolith simulant at the concentration of 0.1 mg/ml were small, as compared with crystalline silica as a positive control. Secretion of IL-1β and tumor necrosis factor-α (TNF-α) was observed at the concentration of 1.0 mg/ml, but induction of gene expression was not observed at 24 h after exposure. Induction of cellular oxidative stress was small. Although the cellular effects tended to be stronger in the < 10 μm particles, there was no remarkable difference. These results suggest that the chemical components and particle size have little relationship to the cellular effects of lunar regolith simulant such as cell membrane damage, induction of oxidative stress and proinflammatory effect.

  3. Lunar Regolith Simulant Feed System for a Hydrogen Reduction Reactor System

    NASA Technical Reports Server (NTRS)

    Mueller, R. P.; Townsend, Ivan I., III

    2009-01-01

    One of the goals of In-Situ Resource Utilization (ISRU) on the moon is to produce oxygen from the lunar regolith which is present in the form of Ilmenite (FeTi03) and other compounds. A reliable and attainable method of extracting some of the oxygen from the lunar regolith is to use the hydrogen reduction process in a hot reactor to create water vapor which is then condensed and electrolyzed to obtain oxygen for use as a consumable. One challenge for a production system is to reliably acquire the regolith with an excavator hauler mobility platform and then introduce it into the reactor inlet tube which is raised from the surface and above the reactor itself. After the reaction, the hot regolith (-1000 C) must be expelled from the reactor for disposal by the excavator hauler mobility system. In addition, the reactor regolith inlet and outlet tubes must be sealed by valves during the reaction in order to allow collection of the water vapor by the chemical processing sub-system. These valves must be able to handle abrasive regolith passing through them as well as the heat conduction from the hot reactor. In 2008, NASA has designed and field tested a hydrogen reduction system called ROxygen in order to demonstrate the feasibility of extracting oxygen from lunar regolith. The field test was performed with volcanic ash known as Tephra on Mauna Kea volcano on the Big Island of Hawai'i. The tephra has similar properties to lunar regolith, so that it is regarded as a good simulant for the hydrogen reduction process. This paper will discuss the design, fabrication, operation, test results and lessons learned with the ROxygen regolith feed system as tested on Mauna Kea in November 2008.

  4. Nonlinear Spectral Mixture Modeling to Estimate Water-Ice Abundance of Martian Regolith

    NASA Astrophysics Data System (ADS)

    Gyalay, Szilard; Chu, Kathryn; Zeev Noe Dobrea, Eldar

    2017-10-01

    We present a novel technique to estimate the abundance of water-ice in the Martian permafrost using Phoenix Surface Stereo Imager multispectral data. In previous work, Cull et al. (2010) estimated the abundance of water-ice in trenches dug by the Mars Phoenix lander by modeling the spectra of the icy regolith using the radiative transfer methods described in Hapke (2008) with optical constants for Mauna Kea palagonite (Clancy et al., 1995) as a substitute for unknown Martian regolith optical constants. Our technique, which uses the radiative transfer methods described in Shkuratov et al. (1999), seeks to eliminate the uncertainty that stems from not knowing the composition of the Martian regolith by using observations of the Martian soil before and after the water-ice has sublimated away. We use observations of the desiccated regolith sample to estimate its complex index of refraction from its spectrum. This removes any a priori assumptions of Martian regolith composition, limiting our free parameters to the estimated real index of refraction of the dry regolith at one specific wavelength, ice grain size, and regolith porosity. We can then model mixtures of regolith and water-ice, fitting to the original icy spectrum to estimate the ice abundance. To constrain the uncertainties in this technique, we performed laboratory measurements of the spectra of known mixtures of water-ice and dry soils as well as those of soils after desiccation with controlled viewing geometries. Finally, we applied the technique to Phoenix Surface Stereo Imager observations and estimated water-ice abundances consistent with pore-fill in the near-surface ice. This abundance is consistent with atmospheric diffusion, which has implications to our understanding of the history of water-ice on Mars and the role of the regolith at high latitudes as a reservoir of atmospheric H2O.

  5. Pneumatic Planetary Regolith Feed System for In-Situ Resource Utilization

    NASA Technical Reports Server (NTRS)

    Mantovani, James G.; Mueller, Robert P.; Townsend, Ivan I.; Craft, Jack; Zacny, Kris

    2010-01-01

    The NASA In-situ Resource Utilization (ISRU) project requires a regolith feed system that can transfer lunar regolith several meters vertically into a chemical reactor for oxygen production on the moon.

  6. Origin and evolution of the lunar regolith; Proceedings of the Symposium, Houston, Tex., November 13-15, 1974

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The papers consider the origin and evolution of the lunar regolith utilizing data obtained during American and Soviet manned and unmanned lunar missions as well as surface and orbital observations, photography, sample collections, and experimental studies. Topics include the transport and emplacement of crater and basin deposits, development of the mare regolith, the shallow lunar structure as determined from the passive seismic experiment, horizontal transport of the regolith, the origin of the exotic component and KREEP-rich materials, the influx of interplanetary materials onto the moon, stratification in the lunar regolith, catastrophic rupture of lunar rocks, cosmic-ray exposure ages of surface features, breccia formation by sintering and crystallization, evolution of the lunar soil, and effects of maturation on the reflectance of the regolith. Individual items are announced in this issue.

  7. Development of a Reactor Model for Chemical Conversion of Lunar Regolith

    NASA Technical Reports Server (NTRS)

    Hegde, U.; Balasubramaniam, R.; Gokoglu, S.

    2009-01-01

    Lunar regolith will be used for a variety of purposes such as oxygen and propellant production and manufacture of various materials. The design and development of chemical conversion reactors for processing lunar regolith will require an understanding of the coupling among the chemical, mass and energy transport processes occurring at the length and time scales of the overall reactor with those occurring at the corresponding scales of the regolith particles. To this end, a coupled transport model is developed using, as an example, the reduction of ilmenite-containing regolith by a continuous flow of hydrogen in a flow-through reactor. The ilmenite conversion occurs on the surface and within the regolith particles. As the ilmenite reduction proceeds, the hydrogen in the reactor is consumed, and this, in turn, affects the conversion rate of the ilmenite in the particles. Several important quantities are identified as a result of the analysis. Reactor scale parameters include the void fraction (i.e., the fraction of the reactor volume not occupied by the regolith particles) and the residence time of hydrogen in the reactor. Particle scale quantities include the time for hydrogen to diffuse into the pores of the regolith particles and the chemical reaction time. The paper investigates the relationships between these quantities and their impact on the regolith conversion. Application of the model to various chemical reactor types, such as fluidized-bed, packed-bed, and rotary-bed configurations, are discussed.

  8. Development of a Reactor Model for Chemical Conversion of Lunar Regolith

    NASA Technical Reports Server (NTRS)

    Hedge, uday; Balasubramaniam, R.; Gokoglu, S.

    2007-01-01

    Lunar regolith will be used for a variety of purposes such as oxygen and propellant production and manufacture of various materials. The design and development of chemical conversion reactors for processing lunar regolith will require an understanding of the coupling among the chemical, mass and energy transport processes occurring at the length and time scales of the overall reactor with those occurring at the corresponding scales of the regolith particles. To this end, a coupled transport model is developed using, as an example, the reduction of ilmenite-containing regolith by a continuous flow of hydrogen in a flow-through reactor. The ilmenite conversion occurs on the surface and within the regolith particles. As the ilmenite reduction proceeds, the hydrogen in the reactor is consumed, and this, in turn, affects the conversion rate of the ilmenite in the particles. Several important quantities are identified as a result of the analysis. Reactor scale parameters include the void fraction (i.e., the fraction of the reactor volume not occupied by the regolith particles) and the residence time of hydrogen in the reactor. Particle scale quantities include the time for hydrogen to diffuse into the pores of the regolith particles and the chemical reaction time. The paper investigates the relationships between these quantities and their impact on the regolith conversion. Application of the model to various chemical reactor types, such as fluidized-bed, packed-bed, and rotary-bed configurations, are discussed.

  9. Parameters and structure of lunar regolith in Chang'E-3 landing area from lunar penetrating radar (LPR) data

    NASA Astrophysics Data System (ADS)

    Dong, Zehua; Fang, Guangyou; Ji, Yicai; Gao, Yunze; Wu, Chao; Zhang, Xiaojuan

    2017-01-01

    Chang'E-3 (CE-3) landed in the northwest Mare Imbrium, a region that has not been explored before. Yutu rover that released by CE-3 lander carried the first lunar surface penetrating radar (LPR) for exploring lunar regolith thickness and subsurface shallow geological structures. In this paper, based on the LPR data and the Panoramic Camera (PC) data, we first calculate the lunar surface regolith parameters in CE-3 landing area including its permittivity, density, conductivity and FeO + TiO2 content. LPR data provides a higher spatial resolution and more accuracy for the lunar regolith parameters comparing to other remote sensing techniques, such as orbit radar sounder and microwave sensing or earth-based powerful radar. We also derived the regolith thickness and its weathered rate with much better accuracy in the landing area. The results indicate that the regolith growth rate is much faster than previous estimation, the regolith parameters are not uniform even in such a small study area and the thickness and growth rate of lunar regolith here are different from other areas in Mare Imbrium. We infer that the main reason should be geological deformation that caused by multiple impacts of meteorites in different sizes.

  10. RASSOR Demonstration in Regolith Bin

    NASA Image and Video Library

    2016-09-29

    An integrated test of the MARCO POLO/Mars Pathfinder in-situ resource utilization, or ISRU, system takes place at NASA’s Kennedy Space Center in Florida. A mockup of MARCO POLO, an ISRU propellant production technology demonstration simulated mission, is tested in a regolith bin with RASSOR 2.0, the Regolith Advanced Surface Systems Operations Robot. On the surface of Mars, mining robots like RASSOR will dig down into the regolith and take the material to a processing plant where usable elements such as hydrogen, oxygen and water can be extracted for life support systems. Regolith also shows promise for both construction and creating elements for rocket fuel.

  11. To the problem about the origin of lunar maria and continents (Moessbauer investigations)

    NASA Technical Reports Server (NTRS)

    Malysheva, T. V.

    1977-01-01

    A comparative study of Mossbauer spectra of regolith returned by the Luna 16 and Luna 20 spacecraft is presented. The Mossbauer spectra of the mare regolith differs significantly for all fractions from the spectra for the same fractions of continental regolith. The total quantity of iron is 1.85 times greater in the mare regolith. There is 2.4 times less olivine in the mare region than in the continental region. The pyroxene component of the mare regolith is less homogeneous in composition (contains more augite and glass) and is present in larger quantities. Ilmenite was found only in the mare regolith. In the continental region, the predominant titanium-containing phase is ulvospinel. The mare regolith contains more metallic iron, which is more finely dispersed and contains less nickel. Troilite is found in the maria region. Based on these differences, it is concluded that the formation of continental rocks occurred at an earlier stage of crystallization from the melt and at higher temperatures and higher partial pressures of oxygen. The mare basalts crystallized from a more reduced magma, apparently in a later process.

  12. A Parametric Sizing Model for Molten Regolith Electrolysis Reactors to Produce Oxygen from Lunar Regolith

    NASA Technical Reports Server (NTRS)

    Schreiner, Samuel S.; Dominguez, Jesus A.; Sibille, Laurent; Hoffman, Jeffrey A.

    2015-01-01

    We present a parametric sizing model for a Molten Electrolysis Reactor that produces oxygen and molten metals from lunar regolith. The model has a foundation of regolith material properties validated using data from Apollo samples and simulants. A multiphysics simulation of an MRE reactor is developed and leveraged to generate a vast database of reactor performance and design trends. A novel design methodology is created which utilizes this database to parametrically design an MRE reactor that 1) can sustain the required mass of molten regolith, current, and operating temperature to meet the desired oxygen production level, 2) can operate for long durations via joule heated, cold wall operation in which molten regolith does not touch the reactor side walls, 3) can support a range of electrode separations to enable operational flexibility. Mass, power, and performance estimates for an MRE reactor are presented for a range of oxygen production levels. The effects of several design variables are explored, including operating temperature, regolith type/composition, batch time, and the degree of operational flexibility.

  13. Lithological influences on contemporary and long-term regolith weathering at the Luquillo Critical Zone Observatory

    USGS Publications Warehouse

    Buss, Heather L.; Lara, Maria Chapela; Moore, Oliver; Kurtz, Andrew C.; Schulz, Marjorie S.; White, Arthur F.

    2017-01-01

    Lithologic differences give rise to the differential weatherability of the Earth’s surface and globally variable silicate weathering fluxes, which provide an important negative feedback on climate over geologic timescales. To isolate the influence of lithology on weathering rates and mechanisms, we compare two nearby catchments in the Luquillo Critical Zone Observatory in Puerto Rico, which have similar climate history, relief and vegetation, but differ in bedrock lithology. Regolith and pore water samples with depth were collected from two ridgetops and at three sites along a slope transect in the volcaniclastic Bisley catchment and compared to existing data from the granitic Río Icacos catchment. The depth variations of solid-state and pore water chemistry and quantitative mineralogy were used to calculate mass transfer (tau) and weathering solute profiles, which in turn were used to determine weathering mechanisms and to estimate weathering rates.Regolith formed on both lithologies is highly leached of most labile elements, although Mg and K are less depleted in the granitic than in the volcaniclastic profiles, reflecting residual biotite in the granitic regolith not present in the volcaniclastics. Profiles of both lithologies that terminate at bedrock corestones are less weathered at depth, near the rock-regolith interfaces. Mg fluxes in the volcaniclastics derive primarily from dissolution of chlorite near the rock-regolith interface and from dissolution of illite and secondary phases in the upper regolith, whereas in the granitic profile, Mg and K fluxes derive from biotite dissolution. Long-term mineral dissolution rates and weathering fluxes were determined by integrating mass losses over the thickness of solid-state weathering fronts, and are therefore averages over the timescale of regolith development. Resulting long-term dissolution rates for minerals in the volcaniclastic regolith include chlorite: 8.9 × 10−14 mol m−2 s−1, illite: 2.1 × 10−14 mol m−2 s−1 and kaolinite: 4.0 × 10−14 mol m−2 s−1. Long-term weathering fluxes are several orders of magnitude lower in the granitic regolith than in the volcaniclastic, despite higher abundances of several elements in the granitic regolith. Contemporary weathering fluxes were determined from net (rain-corrected) solute profiles and thus represent rates over the residence time of water in the regolith. Contemporary weathering fluxes within the granitic regolith are similar to the long-term fluxes. In contrast, the long-term fluxes are faster than the contemporary fluxes in the volcaniclastic regolith. Contemporary fluxes in the granitic regolith are generally also slightly faster than in the volcaniclastic. The differences in weathering fluxes over space and time between these two watersheds indicate significant lithologic control of chemical weathering mechanisms and rates.

  14. Pneumatic Regolith Transfer Systems for In Situ Resource Utilization

    NASA Technical Reports Server (NTRS)

    Mueller, R. P.; Townsend, I. I.; Mantovani, J. G.; Zacny, Kris A.; Craft, Jack

    2010-01-01

    This slide presentation reviews the testing of a pneumatic system for transfering regolith, to be used for In Situ Resource Utilization (ISRU). Using both the simulated microgravity of parabolic flight and ground testing, the tests demonstrated that lunar regolith can be conveyed pneumatically into a simulated ISRU oxygen production plant reactor. The ground testing also demonstrated that the regolith can be expelled from the ISRU reactor for disposal or for other resource processing.

  15. Regolith Depth, Mobility, and Variability on Vesta from Dawn's Low Altitude Mapping Orbit

    NASA Technical Reports Server (NTRS)

    Denevi, B. W.; Coman, E. I.; Blewett, D. T.; Mittlefehldt, D. W.; Buczkowski, D. L.; Combe, J.-P.; De Sanctis, M. C.; Jaumann, R.; Li, J.-Y.; Marchi, S.; hide

    2012-01-01

    Regolith, the fragmental debris layer formed from impact events of all sizes, covers the surface of all asteroids imaged by spacecraft to date. Here we use Framing Camera (FC) images [1] acquired by the Dawn spacecraft [2] from its low-altitude mapping orbit (LAMO) of 210 km (pixel scales of 20 m) to characterize regolith depth, variability, and mobility on Vesta, and to locate areas of especially thin regolith and exposures of competent material. These results will help to evaluate how the surface of this differentiated asteroid has evolved over time, and provide key contextual information for understanding the origin and degree of mixing of the surficial materials for which compositions are estimated [3,4] and the causes of the relative spectral immaturity of the surface [5]. Vestan regolith samples, in the form of howardite meteorites, can be studied in the laboratory to provide complementary constraints on the regolith process [6].

  16. Pneumatic Regolith Transfer Systems for In-Situ Resource Utilization

    NASA Technical Reports Server (NTRS)

    Mueller, Robert P.; Townsend, Ivan I., III; Mantovani, James G.

    2010-01-01

    One aspect of In-Situ Resource Utilization (lSRU) in a lunar environment is to extract oxygen and other elements from the minerals that make up the lunar regolith. Typical ISRU oxygen production processes include but are not limited to hydrogen reduction, carbothermal and molten oxide electrolysis. All of these processes require the transfer of regolith from a supply hopper into a reactor for chemical reaction processing, and the subsequent extraction of the reacted regolith from the reactor. This paper will discuss recent activities in the NASA ISRU project involved with developing pneumatic conveying methods to achieve lunar regolith simulant transfer under I-g and 1/6-g gravitational environments. Examples will be given of hardware that has been developed and tested by NASA on reduced gravity flights. Lessons learned and details of pneumatic regolith transfer systems will be examined as well as the relative performance in a 1/6th G environment

  17. Regolith production rates calculated with uranium-series isotopes at Susquehanna/Shale Hills Critical Zone Observatory

    NASA Astrophysics Data System (ADS)

    Ma, Lin; Chabaux, Francois; Pelt, Eric; Blaes, Estelle; Jin, Lixin; Brantley, Susan

    2010-08-01

    In the Critical Zone where rocks and life interact, bedrock equilibrates to Earth surface conditions, transforming to regolith. The factors that control the rates and mechanisms of formation of regolith, defined here as material that can be augered, are still not fully understood. To quantify regolith formation rates on shale lithology, we measured uranium-series (U-series) isotopes ( 238U, 234U, and 230Th) in three weathering profiles along a planar hillslope at the Susquehanna/Shale Hills Observatory (SSHO) in central Pennsylvania. All regolith samples show significant U-series disequilibrium: ( 234U/ 238U) and ( 230Th/ 238U) activity ratios range from 0.934 to 1.072 and from 0.903 to 1.096, respectively. These values display depth trends that are consistent with fractionation of U-series isotopes during chemical weathering and element transport, i.e., the relative mobility decreases in the order 234U > 238U > 230Th. The activity ratios observed in the regolith samples are explained by i) loss of U-series isotopes during water-rock interactions and ii) re-deposition of U-series isotopes downslope. Loss of U and Th initiates in the meter-thick zone of "bedrock" that cannot be augered but that nonetheless consists of up to 40% clay/silt/sand inferred to have lost K, Mg, Al, and Fe. Apparent equivalent regolith production rates calculated with these isotopes for these profiles decrease exponentially from 45 m/Myr to 17 m/Myr, with increasing regolith thickness from the ridge top to the valley floor. With increasing distance from the ridge top toward the valley, apparent equivalent regolith residence times increase from 7 kyr to 40 kyr. Given that the SSHO experienced peri-glacial climate ˜ 15 kyr ago and has a catchment-wide averaged erosion rate of ˜ 15 m/Myr as inferred from cosmogenic 10Be, we conclude that the hillslope retains regolith formed before the peri-glacial period and is not at geomorphologic steady state. Both chemical weathering reactions of clay minerals and translocation of fine particles/colloids are shown to contribute to mass loss of U and Th from the regolith, consistent with major element data at SSHO. This research documents a case study where U-series isotopes are used to constrain the time scales of chemical weathering and regolith production rates. Regolith production rates at the SSHO should be useful as a reference value for future work at other weathering localities.

  18. Thermal conductivity of lunar regolith simulant JSC-1A under vacuum

    NASA Astrophysics Data System (ADS)

    Sakatani, Naoya; Ogawa, Kazunori; Arakawa, Masahiko; Tanaka, Satoshi

    2018-07-01

    Many air-less planetary bodies, including the Moon, asteroids, and comets, are covered by regolith. The thermal conductivity of the regolith is an essential parameter controlling the surface temperature variation. A thermal conductivity model applicable to natural soils as well as planetary surface regolith is required to analyze infrared remote sensing data. In this study, we investigated the temperature and compressional stress dependence of the thermal conductivity of the lunar regolith simulant JSC-1A, and the temperature dependence of sieved JSC-1A samples under vacuum conditions. We confirmed that a series of the experimental data for JSC-1A are fitted well by our analytical model of the thermal conductivity (Sakatani et al., 2017). Comparison with the calibration data of the sieved samples with those for original JSC-1A indicates that the thermal conductivity of natural samples with a wide grain size distribution can be modeled as mono-sized grains with a volumetric median size. The calibrated model can be used to estimate the volumetric median grain size from infrared remote sensing data. Our experiments and the calibrated model indicates that uncompressed JSC-1A has similar thermal conductivity to lunar top-surface materials, but the lunar subsurface thermal conductivity cannot be explained only by the effects of the density and self-weighted compressional stress. We infer that the nature of the lunar subsurface regolith grains is much different from JSC-1A and lunar top-surface regolith, and/or the lunar subsurface regolith is over-consolidated and the compressional stress higher than the hydrostatic pressure is stored in the lunar regolith layer.

  19. Characterizing the Physical and Thermal Properties of Planetary Regolith at Low Temperatures

    NASA Technical Reports Server (NTRS)

    Mantovani, James G.; Swanger, Adam; Townsend, Ivan I., III; Sibille, Laurent; Galloway, Gregory

    2014-01-01

    The success or failure of in-situ resource utilization for planetary surface exploration-whether for science, colonization, or commercialization-relies heavily on the design and implementation of systems that can effectively process planetary regolith and exploit its potential benefits. In most cases, this challenge necessarily includes the characterization of regolith properties at low temperatures (cryogenic). None of the nearby solar system destinations of interest, such as the moon, Mars and asteroids, possess a sufficient atmosphere to sustain the consistently "high" surface temperatures found on Earth. Therefore, they can experience permanent cryogenic temperatures or dramatic cyclical changes in surface temperature. Characterization of physical properties (e.g., specific heat, thermal and electrical conductivity) over the entire temperature profile is important when planning a mission to a planetary surface; however, the impact on mechanical properties due to the introduction of icy deposits must also be explored in order to devise effective and robust excavation technologies. The Granular Mechanics and Regolith Operations Laboratory and the Cryogenics Test Laboratory at NASA Kennedy Space Center are developing technologies and experimental methods to address these challenges and to aid in the characterization of the physical and mechanical properties of regolith at cryogenic temperatures. This paper will review the current state of knowledge concerning planetary regolith at low temperature, including that of icy regolith, and describe efforts to manipulate icy regolith through novel penetration and excavation techniques.

  20. REE enrichment in granite-derived regolith deposits of the southeast United States: Prospective source rocks and accumulation processes

    USGS Publications Warehouse

    Foley, Nora K.; Ayuso, Robert A.; Simandl, G.J.; Neetz, M.

    2015-01-01

    The Southeastern United States contains numerous anorogenic, or A-type, granites, which constitute promising source rocks for REE-enriched ion adsorption clay deposits due to their inherently high concentrations of REE. These granites have undergone a long history of chemical weathering, resulting in thick granite-derived regoliths, akin to those of South China, which supply virtually all heavy REE and Y, and a significant portion of light REE to global markets. Detailed comparisons of granite regolith profiles formed on the Stewartsville and Striped Rock plutons, and the Robertson River batholith (Virginia) indicate that REE are mobile and can attain grades comparable to those of deposits currently mined in China. A REE-enriched parent, either A-type or I-type (highly fractionated igneous type) granite, is thought to be critical for generating the high concentrations of REE in regolith profiles. One prominent feature we recognize in many granites and mineralized regoliths is the tetrad behaviour displayed in REE chondrite-normalized patterns. Tetrad patterns in granite and regolith result from processes that promote the redistribution, enrichment, and fractionation of REE, such as late- to post- magmatic alteration of granite and silicate hydrolysis in the regolith. Thus, REE patterns showing tetrad effects may be a key for discriminating highly prospective source rocks and regoliths with potential for REE ion adsorption clay deposits.

  1. Spatial Patterns between Regolith Thickness and Forest Productivity in the Southern Sierra CZO

    NASA Astrophysics Data System (ADS)

    Ferrell, R. M.; Ferrell, D. F.; Hartsough, P. C.; O'Geen, T. T.

    2015-12-01

    Soil in conjunction with underlying weathered bedrock make up what is referred to as regolith, which can be thought of as the substrate that actively contributes water and nutrients to above ground biomass. As a result, regolith thickness is an important regulating factor of forest health and drought tolerance in the Sierra Nevada. Our project examined the relationships between landscape position, regolith thickness, and tree productivity within a sub watershed of the Southern Sierra Critical Zone Observatory. We hypothesized that tree productivity will increase with increasing regolith thickness. Data was collected in the summer of 2015 at sixty-five sites within a 522-ha watershed averaging 1180m in elevation with a MAP of 80cm and a MAT of 11C. Sites were randomly selected from a grid and then stratified in the field to capture representative samples from different landscape positions. Regolith was sampled using a hand auger with attachable extensions. At each site we augered to hard bedrock or a maximum depth of 7.56 m, which ever was shallower. Biomass measurements were made for all conifer species (DBH>20cm) within a 10m radius of the primary auger hole. Tree age was measured from a representative tree for all species in the plots. Preliminary findings suggest that there is a weak correlation between landscape position/slope and regolith thickness, likely due to differences in lithology. It also appears that terrain shape can result in conflicting outcomes: 1. It can focus water to promote physical and chemical weathering and thick regolith; or, 2. water focusing can result in landscape scouring, removing soil and weathered bedrock to create shallow regolith. Productivity appears to be a function of regolith thickness, effective precipitation and landscape position. Water collecting areas in the lower watershed are shallow to bedrock, but typically receive high amounts of effective precipitation resulting in greater tree productivity. Moreover, thick regolith in uplands also supports high productivity. Future work will explore the application of terrain attributes computed from DEMs to characterize the contributions of terrain and effective precipitation. As climate change continues it will become increasingly important for land managers to evaluate forest health, productivity and drought tolerance.

  2. Helium mining on the Moon: Site selection and evaluation

    NASA Technical Reports Server (NTRS)

    Cameron, Eugene N.

    1992-01-01

    The feasibility of recovering helium (He) from the Moon as a source of fusion energy on Earth is currently being studied at the University of Wisconsin. Part of this study is selection and evaluation of potential sites for lunar He mining. Selection and evaluation of potential mining sites are based on four salient findings by various investigators of lunar samples: (1) Regoliths from areas underlain by highland materials contain less than 20 wppm He; (2) Certain maria regoliths contain less than 20 wppm He, but other contain 25 to 49 wppm; (3) The He content of a mare regolith is a function of its composition; regoliths rich in Ti are relatively rich in He; and (4) He is concentrated in the less than 100-micron size fractions of regoliths. The first three findings suggest that maria are the most promising mining sites, specifically, those that have high-Ti regoliths. Information on the regional distribution and extent of high-Ti regoliths comes mainly from two sources: direct sampling by various Apollo and Luna missions, and remote sensing by gamma-ray spectroscopy and Earth-based measurements of lunar spectral reflectance. Sampling provides essential control on calibration and interpretation of data from remote sensing. These data indicate that Mare Tranquillitatis is the principal area of high-Ti regolith of the eastern nearside, but large areas of high-Ti regolith are indicated in the Imbrium and Procellarum regions. Recovery of significant amounts of He-3 will require mining billions of tonnes of regolith. Large individual areas suitable for mining must therefore be delineated. The concentration of He in the finer size fractions and considerations of ease of mining mean that mining areas must be as free as possible of sizable craters and blocks of rock. Pending additional lunar missions, information regarding these features must be obtained from lunar photographs, photogeologic maps, and radar surveys. The present study is decidedly preliminary; available information is much to limited to permit even a close approach to final evaluations. As a prelude to recovery of He from the Moon, systematic exploration and sampling of high-Ti regoliths should therefore have a high priority in future lunar missions.

  3. The Regolith of 4 Vesta: Perspectives from Howardite Meteorites and Dawn Mission Observations

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, David W.; Blewett, David T.; Denevi, Brett W.; DeSanctis, M. C.; Jaumann, Ralf; Keller, H. Uwe; Nathues, Andreas; Pieters, Carle M.; Raymond, C. A.; Zuber, Maria T.

    2011-01-01

    4 Vesta is the largest asteroid with a basaltic surface, the only surviving differentiated asteroid recording igneous processes from the earliest phase of solar system history. The Dawn spacecraft is in orbit about Vesta pursuing a campaign of high resolution imaging and visible and infrared spectrometry of the surface; compositional mapping by gamma-ray and neutron spectrometry will follow. Vesta is heavily cratered with a surface covered by impact debris, a regolith. One important goal of the Dawn mission is to develop an understanding of regolith processes that are affecting this surface debris. Regolith characteristics are a record of interaction with the environment (e.g., impactors, dust, solar wind, galactic cosmic-rays) and give evidence of surface processes (down-gravity movement, etc.). Regolith mineralogy and composition reflect the local bedrock, with influences from regional and global mixing. Understanding regolith processes will aid in determining the lithology of underlying crust. Vesta is most likely the parent asteroid of the howardite, eucrite and diogenite meteorites. Eucrites are intrusive and extrusive mafic rocks composed mostly of ferroan low-Ca clinopyroxene and calcic plagioclase, while diogenites are cumulate magnesian orthopyroxenites. Magmatism occurred within a few million years of the formation of the solar system and then ceased. Impacts into the igneous crust produced the howardites - polymict breccias composed of mineral and lithic debris derived mostly from eucrites and diogenites. Some howardites are true regolith breccias formed by lithification of extensively impact-gardened surface debris. However, howardites have a number of significant petrologic and compositional differences from mature lunar regolith breccias and soils reflecting the different environment around Vesta compared to that at 1 AU. The most significant differences are the higher impactor flux with a lower mean impact velocity and the lower gravity. As a result, regolith processes on Vesta differ in detail from those on the Moon. Laboratory study of howardites and orbital investigation of Vesta will allow for development of robust models of regolith formation on hand sample to multi-kilometer scales.

  4. The Reduction of Lunar Regolith by Carbothermal Processing Using Methane

    NASA Technical Reports Server (NTRS)

    Balasubramaniam, R.; Hegde, U.; Gokoglu, S.

    2010-01-01

    The processing of lunar regolith for the production of oxygen is a key component of the In-Situ Resource Utilization plans Currently being developed by NASA. In the carbothermal process, a portion of the surface of the regolith in a container is heated by exposure to a heat source so that a small zone of molten regolith is established. A continuous flow of methane is maintained over the molten regolith zone. In this paper, we discuss the development of a chemical conversion model of the carbothermal process to predict the rate of production of carbon monoxide. Our model is based on a mechanism where methane pyrolyzes when it comes in contact with the surface of the hot molten regolith to form solid carbon and hydrogen gas. Carbon is deposited on the surface of the melt, and hydrogen is released into the gas stream above the melt surface. We assume that the deposited carbon mixes in the molten regolith and reacts with metal oxides in a reduction reaction by which gaseous carbon monoxide is liberated. Carbon monoxide bubbles through the melt and is released into the gas stream. It is further processed downstream to ultimately produce oxygen.

  5. The Reduction of Lunar Regolith by Carbothermal Processing Using Methane

    NASA Technical Reports Server (NTRS)

    Balasubramaniam, R.; Gokoglu, S. A.; Hegde, U.

    2010-01-01

    The processing of lunar regolith for the production of oxygen is a key component of the In-Situ Resource Utilization plans currently being developed by NASA. In the carbothermal process, a portion of the surface of the regolith in a container is heated by exposure to a heat source so that a small zone of molten regolith is established. A continuous flow of methane is maintained over the molten regolith zone. In this paper, we discuss the development of a chemical conversion model of the carbothermal process to predict the rate of production of carbon monoxide. Our model is based on a mechanism where methane pyrolyzes when it comes in contact with the surface of the hot molten regolith to form solid carbon and hydrogen gas. Carbon is deposited on the surface of the melt, and hydrogen is released into the gas stream above the melt surface. We assume that the deposited carbon mixes in the molten regolith and reacts with metal oxides in a reduction reaction by which gaseous carbon monoxide is liberated. Carbon monoxide bubbles through the melt and is released into the gas stream. It is further processed downstream to ultimately produce oxygen.

  6. 3D Additive Construction with Regolith for Surface Systems

    NASA Technical Reports Server (NTRS)

    Mueller, Robert P.

    2014-01-01

    Planetary surface exploration on Asteroids, the Moon, Mars and Martian Moons will require the stabilization of loose, fine, dusty regolith to avoid the effects of vertical lander rocket plume impingement, to keep abrasive and harmful dust from getting lofted and for dust free operations. In addition, the same regolith stabilization process can be used for 3 Dimensional ( 3D) printing, additive construction techniques by repeating the 2D stabilization in many vertical layers. This will allow in-situ construction with regolith so that materials will not have to be transported from Earth. Recent work in the NASA Kennedy Space Center (KSC) Surface Systems Office (NE-S) Swamp Works and at the University of Southern California (USC) under two NASA Innovative Advanced Concept (NIAC) awards have shown promising results with regolith (crushed basalt rock) materials for in-situ heat shields, bricks, landing/launch pads, berms, roads, and other structures that could be fabricated using regolith that is sintered or mixed with a polymer binder. The technical goals and objectives of this project are to prove the feasibility of 3D printing additive construction using planetary regolith simulants and to show that they have structural integrity and practical applications in space exploration.

  7. Reference Images from Thin Sections of Lunar Regolith

    NASA Technical Reports Server (NTRS)

    Rickman Doug; Edmunson, Jennifer

    2013-01-01

    The specialist literature about the lunar regolith is massive. It is also highly focused on specific topics and effectively impenetrable to most non-geologists. Both characteristics of the literature present substantial hurdles to scientists and engineers interested in the regolith In the author's experience it neither surprising or unusual to find serious misconceptions about lunar-type materials outside of the lunar research community. Education of professionals who are non-geologists but interested in the regolith is impeded by a lack of some basic resources. One asset that has been missing is simply detailed images of the regolith "soil". While a few websites offer imagery of specific features, these are of course selected to illustrate specific features. It is almost impossible for a non-specialist to reason from these what "normal" or "typical" regolith looks like. Further, access to lunar material is highly restricted. And as publications rarely do not provide other than highly focused and narrowly tailored data, there is little potential for workers without personal access to sample to do any work with lunar material. To address both problems the authors have begun to make high resolution optical micrographs of entire thin sections of lunar regolith.

  8. Thermal convection in the porous methane-soaked regolith of Titan

    NASA Astrophysics Data System (ADS)

    Czechowski, L. C.; Kossacki, K. J.

    Radar images of Titan surface taken by the Cassini Radar RADAR and Cassini Visual Infrared Mapping Spectrometer VIMS on board of Cassini spacecraft as well as images taken by Descent Imager Spectral Radiometer DISR on board of Huygens lander do not indicate the presence of methane lakes It suggests that the atmospheric methane is supplied from subsurface sources If the whole regolith is highly porous large volume of liquid methane can be stored beneath the surface This hypothesis was discussed in the last decade by several authors It is possible that the regolith was episodically out-gassed Tobie G 37th DPS abstr 53 08 However methane could continuously diffuse to the atmosphere Kossacki K J and Lorenz R 1996 In the present paper we consider convection of liquid methane in the porous methane-soaked regolith Two dimensional numerical model of such convection is developed and applied to simulate processes in the Titan s regolith Basic conditions for the existence of the convection is determined as a function of the regolith layer s thickness its permeability temperature gradient etc We also discuss the role of convection in the process of the exchange of gas beetwen the regolith and Titan s atmosphere

  9. Insights into Regolith Evolution from TEM Studies of Space Weathering of Itokawa Particles

    NASA Technical Reports Server (NTRS)

    Berger, Eve L.; Keller, Lindsay P.

    2015-01-01

    Exposure to solar wind irradiation and micrometeorite impacts alter the properties of regolith materials exposed on airless bodies. However, estimates of space weathering rates for asteroid regoliths span many orders of magnitude. Timescales for space weathering processes on airless bodies can be anchored by analyzing surface samples returned by JAXA's Hayabusa mission to asteroid 25143 Itokawa. Constraints on timescales of solar flare particle track accumulation and formation of solar wind produced ion-damaged rims yield information on regolith dynamics.

  10. RASSOR Mobility

    NASA Image and Video Library

    2017-04-12

    RASSOR 2.0, a mining robot in work for the moon or Mars, shows off its dexterity in the Regolith Bin at Kennedy Space Center. RASSOR stands for Regolith Advanced Surface Systems Operations Robot. On the surface of Mars, mining robots like RASSOR will dig down into the regolith and take the material to a processing plant where usable elements such as hydrogen, oxygen and water can be extracted for life support systems. Regolith also shows promise for both construction and creating elements for rocket fuel.

  11. Exploring Regolith Depth and Cycling on Mars

    NASA Astrophysics Data System (ADS)

    Fassett, C.; Needham, D. H.; Watters, W. A.; Hundal, C.

    2017-12-01

    Regolith or loose sediment is ubiquitous on the surface of Mars, but our understanding of how this fragmental layer forms and evolves with time is limited. In particular, how regolith thickness varies spatially on Mars is not well known. A common perspective is to start from the canonical model for lunar regolith, which is not unreasonable, given that both Mars and the Moon are heavily cratered surfaces. However, this lunar-like paradigm is not supported by observations of Mars from recent missions. On Mars, bedrock exposures are more common and bedrock is generally closer to the surface than on the Moon, and the processes modifying the regolith differ substantially on the two bodies. Moreover, boulders on the Moon have much shorter lifetimes than on Mars, so boulders are much less common on the lunar surface. The sediment transport processes infilling craters differs dramatically on these two bodies as well. On Mars, fine-grained sediment is efficiently transported (advectively) by wind and trapped in craters rapidly after they form. Lateral transport of lunar regolith is comparatively inefficient and dominated by slow impact-driven (diffusive) transport of regolith. The goal of this contribution is to discuss observational constraints on Mars' regolith depth, and to place observations into a model for Mars landform evolution and regolith cycle. Our operating hypothesis is that the inter-crater surface on Mars is comparatively starved of fine-grained sediment (compared to the Moon), because transport and trapping of fines in craters out-competes physical weathering. Moreover, thick sedimentary bodies on Mars often get (weakly) cemented and lithified due to interactions with fluids, even in the most recent, Amazonian epoch. This is consistent with what is observed at the MER and MSL landing sites and what is known from the SNC meteorites.

  12. NASA Lunar Regolith Simulant Program

    NASA Technical Reports Server (NTRS)

    Edmunson, J.; Betts, W.; Rickman, D.; McLemore, C.; Fikes, J.; Stoeser, D.; Wilson, S.; Schrader, C.

    2010-01-01

    Lunar regolith simulant production is absolutely critical to returning man to the Moon. Regolith simulant is used to test hardware exposed to the lunar surface environment, simulate health risks to astronauts, practice in situ resource utilization (ISRU) techniques, and evaluate dust mitigation strategies. Lunar regolith simulant design, production process, and management is a cooperative venture between members of the NASA Marshall Space Flight Center (MSFC) and the U.S. Geological Survey (USGS). The MSFC simulant team is a satellite of the Dust group based at Glenn Research Center. The goals of the cooperative group are to (1) reproduce characteristics of lunar regolith using simulants, (2) produce simulants as cheaply as possible, (3) produce simulants in the amount needed, and (4) produce simulants to meet users? schedules.

  13. The Strata-1 Regolith Dynamics Experiment: Class 1E Science on ISS

    NASA Technical Reports Server (NTRS)

    Fries, Marc; Graham, Lee; John, Kristen

    2016-01-01

    The Strata-1 experiment studies the evolution of small body regolith through long-duration exposure of simulant materials to the microgravity environment on the International Space Station (ISS). This study will record segregation and mechanical dynamics of regolith simulants in a microgravity and vibration environment similar to that experienced by regolith on small Solar System bodies. Strata-1 will help us understand regolith dynamics and will inform design and procedures for landing and setting anchors, safely sampling and moving material on asteroidal surfaces, processing large volumes of material for in situ resource utilization (ISRU) purposes, and, in general, predicting the behavior of large and small particles on disturbed asteroid surfaces. This experiment is providing new insights into small body surface evolution.

  14. Lunar Regolith Characterization for Simulant Design and Evaluation using Figure of Merit Algorithms

    NASA Technical Reports Server (NTRS)

    Schrader, Christian M.; Rickman, Douglas L.; Melemore, Carole A.; Fikes, John C.; Stoeser, Douglas B.; Wentworth, Susan J.; McKay, David S.

    2009-01-01

    NASA's Marshall Space Flight Center (MSFC), in conjunction with the United States Geological Survey (USGS) and aided by personnel from the Astromaterials Research and Exploration Science group at Johnson Space Center (ARES-JSC), is implementing a new data acquisition strategy to support the development and evaluation of lunar regolith simulants. The first analyses of lunar regolith samples by the simulant group were carried out in early 2008 on samples from Apollo 16 core 64001/64002. The results of these analyses are combined with data compiled from the literature to generate a reference composition and particle size distribution (PSD)) for lunar highlands regolith. In this paper we present the specifics of particle type composition and PSD for this reference composition. Furthermore. we use Figure-of-Merit (FoM) routines to measure the characteristics of a number of lunar regolith simulants against this reference composition. The lunar highlands regolith reference composition and the FoM results are presented to guide simulant producers and simulant users in their research and development processes.

  15. Impact comminution of glasses: Implications for lunar regolith evolution

    NASA Technical Reports Server (NTRS)

    Cintala, Mark J.; Smith, Sheila; Hoerz, Friedrich

    1993-01-01

    Glasses are important parts of every lunar regolith sample, whether in the form of indigenous melts such as mesostasis or pyroclastics, or as quenched impact melts. The modal proportions of agglutinitic impact melts alone can exceed 50 percent for some mature regoliths, and glasses are commonly the most dominant single component of lunar soils. They therefore participate in and possibly affect all evolutionary processes to which regoliths are subjected, such as comminution and attendant chemical fractionation as a function of grain size, the retention of solar-wind products, the production of superparamagnetic iron, and others. Because they are such an integral part of lunar regoliths, a more complete understanding of regolith evolution must include the role played by these vitreous components. This contribution examines the comminution behavior of a variety of glasses and a fine-grained basalt under conditions of repetitive impact, and compares this behavior to those of crystalline components, such as lithic fragments and major rock-forming minerals.

  16. Global variations in regolith properties on asteroid Vesta from Dawn's low-altitude mapping orbit

    NASA Astrophysics Data System (ADS)

    Denevi, Brett W.; Beck, Andrew W.; Coman, Ecaterina I.; Thomson, Bradley J.; Ammannito, Eleonora; Blewett, David T.; Sunshine, Jessica M.; de Sanctis, Maria Cristina; Li, Jian-Yang; Marchi, Simone; Mittlefehldt, David W.; Petro, Noah E.; Raymond, Carol A.; Russell, Christopher T.

    2016-12-01

    We investigate the depth, variability, and history of regolith on asteroid Vesta using data from the Dawn spacecraft. High-resolution (15-20 m pixel-1) Framing Camera images are used to assess the presence of morphologic indicators of a shallow regolith, including the presence of blocks in crater ejecta, spur-and-gully-type features in crater walls, and the retention of small (<300 m) impact craters. Such features reveal that the broad, regional heterogeneities observed on Vesta in terms of albedo and surface composition extend to the physical properties of the upper 1 km of the surface. Regions of thin regolith are found within the Rheasilvia basin and at equatorial latitudes from 0-90°E and 260-360°E. Craters in these areas that appear to excavate material from beneath the regolith have more diogenitic (Rheasilvia, 0-90°E) and cumulate eucrite (260-360°E) compositions. A region of especially thick regolith, where depths generally exceed 1 km, is found from 100-240°E and corresponds to heavily cratered, low-albedo surface with a basaltic eucrite composition enriched in carbonaceous chondrite material. The presence of a thick regolith in this area supports the idea that this is an ancient terrain that has accumulated a larger component of exogenic debris. We find evidence for the gardening of crater ejecta toward more howarditic compositions, consistent with regolith mixing being the dominant form of "weathering" on Vesta.

  17. Carbothermal Processing of Lunar Regolith Using Methane

    NASA Technical Reports Server (NTRS)

    Balasubramaniam, R.; Hegde, U.; Gokoglu, S.

    2009-01-01

    The processing of lunar regolith for the production of oxygen is a key component of the In-Situ Resource Utilization plans currently being developed by NASA. Among various candidate processes, the modeling of oxygen production by hydrogen reduction, molten salt electrolysis, and carbothermal processing are presently being pursued. In the carbothermal process, a portion of the surface of the regolith in a container is heated by exposure to a heat source such as a laser beam or a concentrated solar heat flux, so that a small zone of molten regolith is established. The molten zone is surrounded by solid regolith particles that are poor conductors of heat. A continuous flow of methane is maintained over the molten regolith zone. Our model is based on a mechanism where methane pyrolyzes when it comes in contact with the surface of the hot molten regolith to form solid carbon and hydrogen gas. Carbon is deposited on the surface of the melt, and hydrogen is released into the gas stream above the melt surface. We assume that the deposited carbon mixes in the molten regolith and reacts with metal oxides in a reduction reaction by which gaseous carbon monoxide is liberated. Carbon monoxide bubbles through the melt and is released into the gas stream. Oxygen is produced subsequently by (catalytically) processing the carbon monoxide downstream. In this paper, we discuss the development of a chemical conversion model of the carbothermal process to predict the rate of production of carbon monoxide.

  18. Carbothermal Processing of Lunar Regolith Using Methane

    NASA Technical Reports Server (NTRS)

    Balasubramaniam, R.; Hegde, U.; Gokoglu, S.

    2008-01-01

    The processing of lunar regolith for the production of oxygen is a key component of the In-Situ Resource Utilization plans currently being developed by NASA. Among various candidate processes, the modeling of oxygen production by hydrogen reduction, molten salt electrolysis, and carbothermal processing are presently being pursued. In the carbothermal process, a portion of the surface of the regolith in a container is heated by exposure to a heat source such as a laser beam or a concentrated solar heat flux, so that a small zone of molten regolith is established. The molten zone is surrounded by solid regolith particles that are poor conductors of heat. A continuous flow of methane is maintained over the molten regolith zone. Our model is based on a mechanism where methane pyrolyzes when it comes in contact with the surface of the hot molten regolith to form solid carbon and hydrogen gas. Carbon is deposited on the surface of the melt, and hydrogen is released into the gas stream above the melt surface. We assume that the deposited carbon mixes in the molten regolith and reacts with metal oxides in a reduction reaction by which gaseous carbon monoxide is liberated. Carbon monoxide bubbles through the melt and is released into the gas stream. Oxygen is produced subsequently by (catalytically) processing the carbon monoxide downstream. In this paper, we discuss the development of a chemical conversion model of the carbothermal process to predict the rate of production of carbon monoxide.

  19. SSERVI Analog Regolith Simulant Testbed Facility

    NASA Astrophysics Data System (ADS)

    Minafra, J.; Schmidt, G. K.

    2016-12-01

    SSERVI's goals include supporting planetary researchers within NASA, other government agencies; private sector and hardware developers; competitors in focused prize design competitions; and academic sector researchers. The SSERVI Analog Regolith Simulant Testbed provides opportunities for research scientists and engineers to study the effects of regolith analog testbed research in the planetary exploration field. This capability is essential to help to understand the basic effects of continued long-term exposure to a simulated analog test environment. The current facility houses approximately eight tons of JSC-1A lunar regolith simulant in a test bin consisting of a 4 meter by 4 meter area. SSERVI provides a bridge between several groups, joining together researchers from: 1) scientific and exploration communities, 2) multiple disciplines across a wide range of planetary sciences, and 3) domestic and international communities and partnerships. This testbed provides a means of consolidating the tasks of acquisition, storage and safety mitigation in handling large quantities of regolith simulant Facility hardware and environment testing scenarios include, but are not limited to the following; Lunar surface mobility, Dust exposure and mitigation, Regolith handling and excavation, Solar-like illumination, Lunar surface compaction profile, Lofted dust, Mechanical properties of lunar regolith, and Surface features (i.e. grades and rocks) Numerous benefits vary from easy access to a controlled analog regolith simulant testbed, and planetary exploration activities at NASA Research Park, to academia and expanded commercial opportunities in California's Silicon Valley, as well as public outreach and education opportunities.

  20. Investigation of Orthopyroxene Diversity in Howardite Meteorites

    NASA Technical Reports Server (NTRS)

    Johnson, Kristin N.; Herrin, J. S.; Mittlefehldt, D. W.

    2011-01-01

    The howardite, eucrite and diogenite (HED) family of meteorites is considered to originate from the asteroid 4-Vesta [1]. Howardites are polymict breccias made mostly of diogenitic and eucritic debris [2], and have recently been divided into two types: regolithic and fragmental [3]. Regolithic howardites have higher noble gas contents due to solar wind exposure, have a greater abundance of impact-produced glass, are richer in siderophile elements, e.g. Ni, and may preferentially have a mixing ratio of eucrite to diogenite of approx.2:1 [3]. The hypothesis is that these characteristics are a result of originating from an ancient, well-mixed regolith [3]. Fragmental howardites, by contract, show less evidence of regolithic processing and are suggested to have originated in more recently formed impact ejecta [3]. Our work aims to evaluate this hypothesis. We have examined the compositional variations of orthopyroxene (diogenite) clasts within eight howardites. We posited that because regolithic howardites sampled a wider range of the asteroid surface, they would contain orthopyroxene fragments with wider ranges in incompatible element contents than would fragmental howardites that sampled fewer diogenitic source rocks. One purpose of developing an additional method to differentiate regolithic and fragmental howardites is to aid in interpretation of data expected from the Dawn mission to 4-Vesta. The Dawn analyses will be of the regolith layers, making an understanding of regolithic meteorites and the processes by which they were formed an important constraint on understanding Dawn data.

  1. Vacuum Pyrolysis and Related ISRU Techniques

    NASA Technical Reports Server (NTRS)

    Cardiff, Eric H.; Pomeroy, Brian R.; Banks, Ian S.; Benz, Alexis

    2007-01-01

    A number of ISRU-related techniques have been developed at NASA Goddard Space Flight Center. The focus of the team has been on development of the vacuum pyrolysis technique for the production of oxygen from the lunar regolith. However, a number of related techniques have also been developed, including solar concentration, solar heating of regolith, resistive heating of regolith, sintering, regolith boiling, process modeling, parts manufacturing, and instrumentation development. An initial prototype system was developed to vaporize regolith simulants using a approx. l square meter Fresnel lens. This system was successfully used to vaporize quantities of approx. lg, and both mass spectroscopy of the gasses produced and Scanning Electron Microscopy (SEM) of the slag were done to show that oxygen was produced. Subsequent tests have demonstrated the use of a larger system With a 3.8m diameter reflective mirror to vaporize the regolith. These results and modeling of the vacuum pyrolysis reaction have indicated that the vaporization of the oxides in the regolith will occur at lower temperature for stronger vacuums. The chemical modeling was validated by testing of a resistive heating system that vaporized quantities of approx. 10g of MLS-1A. This system was also used to demonstrate the sintering of regolith simulants at reduced temperatures in high vacuum. This reduction in the required temperature prompted the development of a small-scale resistive heating system for application as a scientific instrument as well as a proof-of principle experiment for oxygen production.

  2. Towards a Regolith Maturity Index for Howardites

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, David W.; Cartwright, J. A.; Herrin, J. S.; Johnson, K. N.

    2011-01-01

    The Dawn spacecraft has just arrived at asteroid 4 Vesta, parent of the howardite, eucrite and diogenite (HED) meteorites [1], to begin a yearlong surface study from orbit [2]. As Dawn will view a debris-covered surface, understanding the formation and mixing processes for the debris layer will strongly aid surface data interpretations. Howardites are polymict breccias mainly composed of clasts derived from basaltic (eucritic) and orthopy-roxenitic (diogenitic) parent materials [3]. Some howardites are poorly reworked (fragmental howardites) whilst others have been extensively gardened in an active regolith (regolithic howardites) [4]. The latter may represent an ancient, well-mixed regolith, whilst the former may be from more recent ejecta deposits [4]. Due to environmental differences, regolith development on Vesta differs in detail from that on the Moon [4-6]. We have been developing petrological criteria to apply to howardite thin sections to determine their relative regolithic maturity, which we are fine-tuning with comparison to noble gas data [7, 8]. Whilst we previously emphasized the abundance of reworked clasts (fragmental and impact-melt breccia clasts), this is an imperfect criterion: one howardite with abundant re-worked clasts (EET 99408) shows no evidence of solar wind Ne (SW-Ne), yet, two of our alleged fragmental howardites have clear SW-Ne signatures (LEW 85313, MET 00423) [7, 8]. We are now investigating the diversity in minor and trace element contents of low-Ca pyroxene clasts in howardites as a measure of regolith grade, and will begin analyses of such grains within reworked clasts. Our hypothesis is that regolithic howardites (and the breccia clasts they contain) will show greater diversity because they sampled more diverse diogenitic plutons than fragmental howardites, which formed from ejecta from only a few impacts [e.g. 4]. Our initial LA-ICP-MS work showed ranges in trace element diversity in low-Ca pyroxenes (estimated from the standard error of the mean of analyses), where those howardites considered of medium to high regolithic grade showed greater diversity [9]. Our EMPA results (from a larger howardite suite) show an overall greater diversity in our putative medium to high regolithic grade howardites, though there are exceptions. The greatest diversity is found for paired howardites GRO 95574 and GRO 95581, which were not considered regolithic in our initial study. We will continue investigating avenues to determine regolith maturity in thin section, factoring in bulk rock compositional data, and will coordinate these studies with noble gas results.

  3. A TOF-SIMS Investigation of the Volatile Inventory of Lithic and Mineral Clasts in Lunar Regolith Samples

    NASA Astrophysics Data System (ADS)

    Tartèse, R.; Lyon, I. C.

    2017-07-01

    The lunar regolith offers a key record to characterise the transfer of volatiles across the solar system for the past 4.5 billion years. We tackle this issue by investigating the volatile inventory of lunar regolith samples using TOF-SIMS.

  4. The Nature of C Asteroid Regolith from Meteorite Observations

    NASA Technical Reports Server (NTRS)

    Zolensky, M.; Mikouchi, T.; Hagiya, K.; Ohsumi, K.; Komatsu, M.; Jenniskens, P.; Le, L.; Yin, Q.-Z; Kebukawa, Y.; Fries, M.

    2013-01-01

    Regolith from C (and related) asteroid bodies are a focus of the current missions Dawn at Ceres, Hayabusa 2 and OSIRIS REx. An asteroid as large as Ceres is expected to be covered by a mature regolith, and as Hayabusa demonstrated, flat and therefore engineeringly-safe ponded deposits will probably be the sampling sites for both Hayabusa 2 and OSIRIS REx. Here we examine what we have learned about the mineralogy of fine-grained asteroid regolith from recent meteorite studies and the examination of the samples harvested from asteroid Itokawa by Hayabusa.

  5. Rethinking of the regolith transport on airless bodies in the Solar system

    NASA Astrophysics Data System (ADS)

    Hsu, S.; Wang, X.; Seiss, M.; Schwan, J.; Sternovsky, Z.; Horanyi, M.

    2016-12-01

    Recent laboratory experiments provided important constraints on the characteristics of electrostatic dust transport on airless bodies. The proposed "patched charging model" illustrates how regolith particles acquire grain charges much higher than expected to drive the surface dust movements, including rotation and hopping of individual regolith particle as well as the overall smoothing of the regolith surface observed in the experiments. Here we apply the experimental results to re-examine the regolith transport on the airless bodies in the Solar systems, including both observation (e.g., dust ponds on Eros) and theoretical aspects (e.g., electrostatic dust levitation). We will also discuss the observational criteria and implications to be expected from current and future missions, such as Asteroid Redirect Mission, Cassini, Hayabusa 2, and OSIRIS-Rex.

  6. Thermal fatigue as the origin of regolith on small asteroids.

    PubMed

    Delbo, Marco; Libourel, Guy; Wilkerson, Justin; Murdoch, Naomi; Michel, Patrick; Ramesh, K T; Ganino, Clément; Verati, Chrystele; Marchi, Simone

    2014-04-10

    Space missions and thermal infrared observations have shown that small asteroids (kilometre-sized or smaller) are covered by a layer of centimetre-sized or smaller particles, which constitute the regolith. Regolith generation has traditionally been attributed to the fall back of impact ejecta and by the break-up of boulders by micrometeoroid impact. Laboratory experiments and impact models, however, show that crater ejecta velocities are typically greater than several tens of centimetres per second, which corresponds to the gravitational escape velocity of kilometre-sized asteroids. Therefore, impact debris cannot be the main source of regolith on small asteroids. Here we report that thermal fatigue, a mechanism of rock weathering and fragmentation with no subsequent ejection, is the dominant process governing regolith generation on small asteroids. We find that thermal fragmentation induced by the diurnal temperature variations breaks up rocks larger than a few centimetres more quickly than do micrometeoroid impacts. Because thermal fragmentation is independent of asteroid size, this process can also contribute to regolith production on larger asteroids. Production of fresh regolith originating in thermal fatigue fragmentation may be an important process for the rejuvenation of the surfaces of near-Earth asteroids, and may explain the observed lack of low-perihelion, carbonaceous, near-Earth asteroids.

  7. VAPoR - Volatile Analysis by Pyrolysis of Regolith - an Instrument for In Situ Detection of Water, Noble Gases, and Organics on the Moon

    NASA Technical Reports Server (NTRS)

    ten Kate, I. L.; Cardiff, E. H.; Feng, S. H.; Holmes, V.; Malespin, C.; Stern, J. G.; Swindle, T. D.; Glavin, D. P.

    2010-01-01

    We present the Volatile Analysis by Pyrolysis of Regolith (VAPoR) instrument design and demonstrate the validity of an in situ pyrolysis mass spectrometer for evolved gas analyses of lunar and planetary regolith samples. In situ evolved gas analyses of the lunar regolith have not yet been carried out and no atmospheric or evolved gas measurements have been made at the lunar poles. VAPoR is designed to do both kinds of measurements, is currently under development at NASA's Goddard Space Flight Center, and will be able to heat powdered regolith samples or rock drill fines up to 1400 C in vacuo. To validate the instrument concept, evolved gas species released from different planetary analogs were determined as a function of temperature using a laboratory breadboard. Evolved gas measurements of an Apollo 16 regolith sample and a fragment of the carbonaceous meteorite Murchison were made by VAPoR and our results compared with existing data. The results imply that in situ evolved gas measurements of the lunar regolith at the polar regions by VAPoR will be a very powerful tool for identifying water and other volatile signatures of lunar or exogenous origin as potential resources for future human exploration.

  8. A new parameterization of regolith formation and the response time of weathering front propagation to climate and tectonic forcing

    NASA Astrophysics Data System (ADS)

    Braun, Jean

    2017-04-01

    The thickness of the regolith remains one of the most difficult elements of the critical zone to predict or quantify. The regolith hosts a substantial proportion of the world's freshwater reservoir and its shape and physical properties control the hydrology of most river catchments, which is essential to the development and evolution of many eco-systems. The base of the regolith is controlled by the propagation of a weathering front through a range of chemical and physical processes, such as primary mineral dissolution, frost cracking or fracturing helped by topographic stress. We have recently parameterize the evolution of the weathering front under the relatively well accepted assumption that the rate of weathering front propagation, Ḃ, is directly proportional to the velocity of the fluid circulating within the regolith v, i.e. Ḃ = Fv. This approach is justified in most situations where chemical dissolution of highly soluble minerals is thought to dominate the transformation of bedrock into regolith. Under this assumption, the thickness of the regolith reaches a steady-state under the combined effects of weathering front propagation at its base and surface erosion, and the distribution of the regolith is controlled by two dimensionless numbers. The first : Ω = FKS/˙ɛ depends on the surface slope, S, and the steady-state erosion rate, ˙ɛ, through the hydraulic conductivity K and F ; the second: Γ = KS2/P depends on the surface slope and the mean precipitation rate, P . Ω controls the mean thickness of the regolith layer and needs to be larger than unity (i.e. ɛ˙ < FKS) for the regolith layer to exists. We have also shown that Ω is the ratio between the erosional response time of the system LS/ɛ˙ and the weathering response time of the system LF/K implying that where regolith is present at the Earth surface and erosional steady-state, i.e. between uplift and surface erosion, has been reached, the regolith thickness must have reached steady-state as well. On the other hand, Γ controls the shape of the regolith layer and, more precisely, whether it thickens towards the top (Γ > 1) or towards the base (Γ < 1) of topographic features. Our simple parameterization therefore explains why the regolith is thickest on top of hills in tectonically active areas, i.e. where slopes are elevated, and more uniformly distributed or even thickest near base level in tectonically quiescent areas, i.e. in anorogenic areas such as in most continental interiors. These fundamental results have now been expanded to more realistic two-dimensional numerical simulations in which drainage density is dynamically determined by the onset of surface flow, i.e. where the water table intersects the topographic surface. In this way, the length scale of water table connectivity, L, which controls the value of all of the system response times (erosional, weathering and hydraulic) is determined in a self-consistent manner which allows us to predict more accurately the range of responses of the system to tectonic and climatic changes at a variety of forcing periods.

  9. Water Retention in Mature and Immature Lunar Regolith

    NASA Astrophysics Data System (ADS)

    Flom, A. J.; Kramer, G. Y.; Combe, J. P.

    2017-12-01

    The study of water and hydroxyl (HOH/OH) in lunar regolith and how it is retained has important implications for understanding how the Solar System and the Moon were formed. As a "hydration" phenomenon, understanding the process may provide a vital resource in space exploration. This study looks at how the amount of surface HOH/OH changes over time (eons) in lunar regolith. This is done by comparing the spectral absorption feature in the 3 micron area in Moon Mineralogy Mapper (M3) data [1]. This area of the spectrum is affected by thermal emission and it is known that the initial M3 correction for this is was not sufficient. To correct for this, a new thermal correction has been done on the data using a surface roughness model. With this correction, the 3 micron area spectral absorption feature between mature regolith (that has been exposed to weathering processes on the surface) against immature regolith (in fresh crater ejecta which has been mostly unaffected by these processes) [2]. It is commonly believed that HOH/OH is being formed due to hydrogen atoms from the solar wind interacting with oxygen in lunar minerals. There are a couple competing hypotheses about the process that dominates retaining this HOH/OH once it forms. The first suggests that the exposed oxygen atoms on freshly fractured mineral surfaces facilitate adsorption of protons. Alternately, a second proposes that HOH/OH is trapped in vesicles in the glassy parts of more mature regolith. The first hypothesis would lead to the mature regolith having a weaker HOH/OH absorption than immature regolith, because its weathered glassy coating would prevent it from capturing hydrogen atoms as efficiently. The second hypothesis would lead to the mature regolith having a stronger absorption because the glassy component of the regolith increases with maturity, and therefore so do the vesicles in that glassy coating. This study looks at fresh craters across Crisium, South Pole Aitken, and Reiner Gamma in order to identify a trend across many different terrains and compare these two hypotheses. References [1] Pieters, C. M. et al. (2009) Science 326 [2] Kramer, G.Y. and Combe, J-P. (2016) LPSC 47

  10. Low Force Penetration of Icy Regolith

    NASA Technical Reports Server (NTRS)

    Mantovani, J. G.; Galloway, G. M.; Zacny, K.

    2016-01-01

    A percussive cone penetrometer measures the strength of granular material by using percussion to deliver mechanical energy into the material. A percussive cone penetrometer was used in this study to penetrate a regolith ice mixture by breaking up ice and decompacting the regolith. As compared to a static cone penetrometer, percussion allows low reaction forces to push a penetrometer probe tip more easily into dry regolith in a low gravity environment from a planetary surface rover or a landed spacecraft. A percussive cone penetrates icy regolith at ice concentrations that a static cone cannot penetrate. In this study, the percussive penetrator was able to penetrate material under 65 N of down-force which could not be penetrated using a static cone under full body weight. This paper discusses using a percussive cone penetrometer to discern changes in the concentration of water-ice in a mixture of lunar regolith simulant and ice to a depth of one meter. The rate of penetration was found to be a function of the ice content and was not significantly affected by the down-force. The test results demonstrate that this method may be ideal for a small platform in a reduced gravity environment. However, there are some cases where the system may not be able to penetrate the icy regolith, and there is some risk of the probe tip becoming stuck so that it cannot be retracted. It is also shown that a percussive cone penetrometer could be used to prospect for water ice in regolith at concentrations as high as 8 by weight.

  11. Characterising and modelling regolith stratigraphy using multiple geophysical techniques

    NASA Astrophysics Data System (ADS)

    Thomas, M.; Cremasco, D.; Fotheringham, T.; Hatch, M. A.; Triantifillis, J.; Wilford, J.

    2013-12-01

    Regolith is the weathered, typically mineral-rich layer from fresh bedrock to land surface. It encompasses soil (A, E and B horizons) that has undergone pedogenesis. Below is the weathered C horizon that retains at least some of the original rocky fabric and structure. At the base of this is the lower regolith boundary of continuous hard bedrock (the R horizon). Regolith may be absent, e.g. at rocky outcrops, or may be many 10's of metres deep. Comparatively little is known about regolith, and critical questions remain regarding composition and characteristics - especially deeper where the challenge of collecting reliable data increases with depth. In Australia research is underway to characterise and map regolith using consistent methods at scales ranging from local (e.g. hillslope) to continental scales. These efforts are driven by many research needs, including Critical Zone modelling and simulation. Pilot research in South Australia using digitally-based environmental correlation techniques modelled the depth to bedrock to 9 m for an upland area of 128 000 ha. One finding was the inability to reliably model local scale depth variations over horizontal distances of 2 - 3 m and vertical distances of 1 - 2 m. The need to better characterise variations in regolith to strengthen models at these fine scales was discussed. Addressing this need, we describe high intensity, ground-based multi-sensor geophysical profiling of three hillslope transects in different regolith-landscape settings to characterise fine resolution (i.e. < 1 m) regolith stratigraphy. The geophysics included: ground penetrating radar collected at a number of frequencies; multiple frequency, multiple coil electromagnetic induction; and high resolution resistivity. These were accompanied by georeferenced, closely spaced deep cores to 9 m - or to core refusal. The intact cores were sub-sampled to standard depths and analysed for regolith properties to compile core datasets consisting of: water content; texture; electrical conductivity; and weathered state. After preprocessing (filtering, geo-registration, depth correction, etc.) each geophysical profile was evaluated by matching the core data. Applying traditional geophysical techniques, the best profiles were inverted using the core data creating two-dimensional (2-D) stratigraphic regolith models for each transect, and evaluated using independent validation. Next, in a test of an alternative method borrowed from digital soil mapping, the best preprocessed geophysical profiles were co-registered and stratigraphic models for each property created using multivariate environmental correlation. After independent validation, the qualities of the latest models were compared to the traditionally derived 2-D inverted models. Finally, the best overall stratigraphic models were used in conjunction with local environmental data (e.g. geology, geochemistry, terrain, soils) to create conceptual regolith hillslope models for each transect highlighting important features and processes, e.g. morphology, hydropedology and weathering characteristics. Results are presented with recommendations regarding the use of geophysics in modelling regolith stratigraphy at fine scales.

  12. Dynamic loading and release in Johnson Space Center Lunar regolith simulant

    NASA Astrophysics Data System (ADS)

    Plesko, C. S.; Jensen, B. J.; Wescott, B. L.; Skinner McKee, T. E.

    2011-10-01

    The behavior of regolith under dynamic loading is important for the study of planetary evolution, impact cratering, and other topics. Here we present the initial results of explosively driven flier plate experiments and numerical models of compaction and release in samples of the JSC-1A Lunar regolith simulant.

  13. Regolith Advanced Surface Systems Operations Robot Excavator

    NASA Technical Reports Server (NTRS)

    Mueller, Robert P.; Smith, Jonathan D.; Ebert, Thomas; Cox, Rachel; Rahmatian, Laila; Wood, James; Schuler, Jason; Nick, Andrew

    2013-01-01

    The Regolith Advanced Surface Systems Operations Robot (RASSOR) excavator robot is a teleoperated mobility platform with a space regolith excavation capability. This more compact, lightweight design (<50 kg) has counterrotating bucket drums, which results in a net-zero reaction horizontal force due to the self-cancellation of the symmetrical, equal but opposing, digging forces.

  14. Experimental determination of in situ utilization of lunar regolith for thermal energy storage

    NASA Technical Reports Server (NTRS)

    Richter, Scott W.

    1992-01-01

    A Lunar Thermal Energy from Regolith (LUTHER) experiment has been designed and fabricated at the NASA Lewis Research Center to determine the feasibility of using lunar soil as thermal energy storage media. The experimental apparatus includes an alumina ceramic canister which contains simulated lunar regolith, a heater, nine heat shields, a heat transfer cold jacket, and 19 type-B platinum rhodium thermocouples. The simulated lunar regolith is a basalt that closely resembles the lunar basalt returned to earth by the Apollo missions. The experiment will test the effects of vacuum, particle size, and density on the thermophysical properties of the regolith, which include melt temperature, specific heat thermal conductivity, and latent heat of storage. Two separate tests, using two different heaters, will be performed to study the effect of heating the system using radiative and conductive heat transfer. A finite differencing SINDA model was developed at NASA Lewis Research Center to predict the performance of the LUTHER experiment. The code will predict the effects of vacuum, particle size, and density has on the heat transfer to the simulated regolith.

  15. Apollo 16 regolith breccias and soils - Recorders of exotic component addition to the Descartes region of the moon

    NASA Technical Reports Server (NTRS)

    Simon, S. B.; Papike, J. J.; Laul, J. C.; Hughes, S. S.; Schmitt, R. A.

    1988-01-01

    Using the subdivision of Apollo 16 regolith breccias into ancient (about 4 Gyr) and younger samples (McKay et al., 1986), with the present-day soils as a third sample, a petrologic and chemical determination of regolith evolution and exotic component addition at the A-16 site was performed. The modal petrologies and mineral and chemical compositions of the regolith breccias in the region are presented. It is shown that the early regolith was composed of fragments of plutonic rocks, impact melt rocks, and minerals and impact glasses. It is found that KREEP lithologies and impact melts formed early in lunar history. The mare components, mainly orange high-TiO2 glass and green low-TiO2 glass, were added to the site after formation of the ancient breccias and prior to the formation of young breccias. The major change in the regolith since the formation of the young breccias is an increase in maturity represented by the formation of fused soil particles with prolonged exposure to micrometeorite impacts.

  16. Chemical composition of crystalline rock fragments from Luna 16 and Luna 20 fines

    NASA Technical Reports Server (NTRS)

    Cimbalnikova, A.; Palivcova, M.; Frana, J.; Mastalka, A.

    1977-01-01

    The chemical composition (bulk, rare earth, and trace elements) of the Luna 16 mare regolith and luna 20 highland regolith is discussed. The rock samples considered are 14 basaltic rock fragments (Luna 16) and 13 rock fragments of the ANT suite (Luna 20). On the basis of bulk composition, two types of basaltic rocks have been differentiated and defined in the Luna 16 regolith: mare basalts (fundamental crystalline rocks of Mare Fecunditatis) and high-alumina basalts. The bulk analyses of rock fragments of the ANT suite also enabled distinction of two rock types: anorthositic norites and troctolites and/or spinal-troctolites (the most abundant crystalline rocks of the highland region, the landing site of luna 20), and anorthosites. The chemical compositions of Luna 16 and Luna 20 regolith samples are compared. Differences in the chemistry of the Luna 16 mare regolith and that of mare basalts are discussed. The chemical affinity between the Luna 20 highland regolith and (a) anorthositic norites and (b) troctolites and/or spinel-troctolites has been ascertained.

  17. Sustainable Human Presence on the Moon using In Situ Resources

    NASA Technical Reports Server (NTRS)

    McLemore, Carol A.; Fikes, John C.; McCarley, Kevin S.; Darby, Charles A.; Curreri, Peter A.; Kennedy, James P.; Good, James E.; Gilley, Scott D.

    2008-01-01

    New capabilities, technologies and infrastructure must be developed to enable a sustained human presence on the moon and beyond. The key to having this permanent presence is the utilization of in situ resources. To this end, NASA is investigating how in situ resources can be utilized to improve mission success by reducing up-mass, improving safety, reducing risk, and bringing down costs for the overall mission. To ensure that this capability is available when needed, technology development is required now. NASA/Marshall Space Flight Center (MSFC) is supporting this endeavor, along with other NASA centers, by exploring how lunar regolith can be mined for uses such as construction, life support, propulsion, power, and fabrication. Efforts at MSFC include development of lunar regolith simulant for hardware testing and development, extraction of oxygen and other materials from the lunar regolith, production of parts and tools on the moon from local materials or from provisioned feedstocks, and capabilities to show that produced parts are "ready for use". This paper discusses the lunar regolith, how the regolith is being replicated in the development of simulants and possible uses of the regolith.

  18. Regolith evolution in the laboratory - Scaling dissimilar comminution experiments

    NASA Technical Reports Server (NTRS)

    Cintala, Mark J.; Horz, Friedrich

    1990-01-01

    Repeated impacts into fragmental targets simulating unconsolidated debris on planetary surfaces have provided empirical insight into the evolution of planetary regoliths. The techniques of dimensional analysis have been employed to quantify and examine the relationships between the more important variables in the evolution of these experimental regoliths. Application of this method to the results of 10 experimental series shows that the quantity of comminuted target mass is directly proportional to (1) the number of impacts, (2) the diameter of the projectile, (3) the mean size of the crystals, (4) the mean grain size of the evolving regolith, (5) the total target mass, (6) the impactor density, and (7) the ratio of the impact velocity to the velocity of sound in the target rock. The comminuted mass is inversely proportional to the density of the target rock and the sorting of the regolith.

  19. Regolith-Derived Heat Shield for Planetary Body Entry and Descent System with In Situ Fabrication

    NASA Technical Reports Server (NTRS)

    Hogue, Michael D.; Mueller, Robert P.; Rasky, Daniel J.; Hintze, Paul E.; Sibille, Laurent

    2011-01-01

    In this paper we will discuss a new mass-efficient and innovative way of protecting high-mass spacecraft during planetary Entry, Descent & Landing (EDL). Heat shields fabricated in situ can provide a thermal-protection system (TPS) for spacecraft that routinely enter a planetary atmosphere. By fabricating the heat shield with space resources from regolith materials available on moons and asteroids, it is possible to avoid launching the heat-shield mass from Earth. Three regolith processing and manufacturing methods will be discussed: 1) oxygen & metal extraction ISRU processes produce glassy melts enriched in alumina and titania, processed to obtain variable density, high melting point and heat-resistance; 2) compression and sintering of the regolith yield low density materials; 3) in-situ derived high-temperature polymers are created to bind regolith particles together, with a lower energy budget.

  20. Regolith-Derived Heat Shield for Planetary Body Entry and Descent System with In Situ Fabrication

    NASA Technical Reports Server (NTRS)

    Hogue, Michael D.; Mueller, Robert P.; Rasky, Daniel; Hintze, Paul; Sibille, Laurent

    2012-01-01

    In this paper we will discuss a new mass-efficient and innovative way of protecting high-mass spacecraft during planetary Entry, Descent & Landing (EDL). Heat shields fabricated in situ can provide a thermal-protection system (TPS) for spacecraft that routinely enter a planetary atmosphere. By fabricating the heat shield with space resources from regolith materials available on moons and asteroids, it is possible to avoid launching the heat-shield mass from Earth. Two regolith processing and manufacturing methods will be discussed: 1) Compression and sintering of the regolith to yield low density materials; 2) Formulations of a High-temperature silicone RTV (Room Temperature Vulcanizing) compound are used to bind regolith particles together. The overall positive results of torch flame impingement tests and plasma arc jet testing on the resulting samples will also be discussed.

  1. A New Kinetic Simulation Model with Self-Consistent Calculation of Regolith Layer Charging for Moon-Plasma Interactions

    NASA Astrophysics Data System (ADS)

    Han, D.; Wang, J.

    2015-12-01

    The moon-plasma interactions and the resulting surface charging have been subjects of extensive recent investigations. While many particle-in-cell (PIC) based simulation models have been developed, all existing PIC simulation models treat the surface of the Moon as a boundary condition to the plasma flow. In such models, the surface of the Moon is typically limited to simple geometry configurations, the surface floating potential is calculated from a simplified current balance condition, and the electric field inside the regolith layer cannot be resolved. This paper presents a new full particle PIC model to simulate local scale plasma flow and surface charging. A major feature of this new model is that the surface is treated as an "interface" between two mediums rather than a boundary, and the simulation domain includes not only the plasma but also the regolith layer and the bedrock underneath it. There are no limitations on the surface shape. An immersed-finite-element field solver is applied which calculates the regolith surface floating potential and the electric field inside the regolith layer directly from local charge deposition. The material property of the regolith layer is also explicitly included in simulation. This new model is capable of providing a self-consistent solution to the plasma flow field, lunar surface charging, the electric field inside the regolith layer and the bedrock for realistic surface terrain. This new model is applied to simulate lunar surface-plasma interactions and surface charging under various ambient plasma conditions. The focus is on the lunar terminator region, where the combined effects from the low sun elevation angle and the localized plasma wake generated by plasma flow over a rugged terrain can generate strongly differentially charged surfaces and complex dust dynamics. We discuss the effects of the regolith properties and regolith layer charging on the plasma flow field, dust levitation, and dust transport.

  2. Low-Energy Impacts onto Lunar Regolith Simulant

    NASA Astrophysics Data System (ADS)

    Seward, Laura M.; Colwell, J.; Mellon, M.; Stemm, B.

    2012-10-01

    Low-Energy Impacts onto Lunar Regolith Simulant Laura M. Seward1, Joshua E. Colwell1, Michael T. Mellon2, and Bradley A. Stemm1, 1Department of Physics, University of Central Florida, Orlando, Florida, 2Southwest Research Institute, Boulder, Colorado. Impacts and cratering in space play important roles in the formation and evolution of planetary bodies. Low-velocity impacts and disturbances to planetary regolith are also a consequence of manned and robotic exploration of planetary bodies such as the Moon, Mars, and asteroids. We are conducting a program of laboratory experiments to study low-velocity impacts of 1 to 5 m/s into JSC-1 lunar regolith simulant, JSC-Mars-1 Martian regolith simulant, and silica targets under 1 g. We use direct measurement of ejecta mass and high-resolution video tracking of ejecta particle trajectories to derive ejecta mass velocity distributions. Additionally, we conduct similar experiments under microgravity conditions in a laboratory drop tower and on parabolic aircraft with velocities as low as 10 cm/s. We wish to characterize and understand the collision parameters that control the outcome of low-velocity impacts into regolith, including impact velocity, impactor mass, target shape and size distribution, regolith depth, target relative density, and crater depth, and to experimentally determine the functional dependencies of the outcomes of low-velocity collisions (ejecta mass and ejecta velocities) on the controlling parameters of the collision. We present results from our ongoing study showing the positive correlation between impact energy and ejecta mass. The total ejecta mass is also dependent on the packing density (porosity) of the regolith. We find that ejecta mass velocity fits a power-law or broken power-law distribution. Our goal is to understand the physics of ejecta production and regolith compaction in low-energy impacts and experimentally validate predictive models for dust flow and deposition. We will present our results from one-g and microgravity impact experiments.

  3. Regolith-geology mapping with support vector machine: A case study over weathered Ni-bearing peridotites, New Caledonia

    NASA Astrophysics Data System (ADS)

    De Boissieu, Florian; Sevin, Brice; Cudahy, Thomas; Mangeas, Morgan; Chevrel, Stéphane; Ong, Cindy; Rodger, Andrew; Maurizot, Pierre; Laukamp, Carsten; Lau, Ian; Touraivane, Touraivane; Cluzel, Dominique; Despinoy, Marc

    2018-02-01

    Accurate maps of Earth's geology, especially its regolith, are required for managing the sustainable exploration and development of mineral resources. This paper shows how airborne imaging hyperspectral data collected over weathered peridotite rocks in vegetated, mountainous terrane in New Caledonia were processed using a combination of methods to generate a regolith-geology map that could be used for more efficiently targeting Ni exploration. The image processing combined two usual methods, which are spectral feature extraction and support vector machine (SVM). This rationale being the spectral features extraction can rapidly reduce data complexity by both targeting only the diagnostic mineral absorptions and masking those pixels complicated by vegetation, cloud and deep shade. SVM is a supervised classification method able to generate an optimal non-linear classifier with these features that generalises well even with limited training data. Key minerals targeted are serpentine, which is considered as an indicator for hydrolysed peridotitic rock, and iron oxy-hydroxides (hematite and goethite), which are considered as diagnostic of laterite development. The final classified regolith map was assessed against interpreted regolith field sites, which yielded approximately 70% similarity for all unit types, as well as against a regolith-geology map interpreted using traditional datasets (not hyperspectral imagery). Importantly, the hyperspectral derived mineral map provided much greater detail enabling a more precise understanding of the regolith-geological architecture where there are exposed soils and rocks.

  4. Long-Range Transhorizon Lunar Surface Radio Wave Propagation in the Presence of a Regolith and a Sparse Exospheric Plasma

    NASA Technical Reports Server (NTRS)

    Manning, Robert M.

    2008-01-01

    Long-range, over-the-horizon (transhorizon) radio wave propagation is considered for the case of the Moon. In the event that relay satellites are not available or otherwise unwarranted for use, transhorizon communication provides for a contingency or backup option for non line-of-sight lunar surface exploration scenarios. Two potential low-frequency propagation mechanisms characteristic of the lunar landscape are the lunar regolith and the photoelectron induced plasma exosphere enveloping the Moon. Although it was hoped that the regolith would provide for a spherical waveguide which could support a trapped surface wave phenomena, it is found that, in most cases, the regolith is deleterious to long range radio wave propagation. However, the presence of the plasma of the lunar exosphere supports wave propagation and, in fact, surpasses the attenuation of the regolith. Given the models of the regolith and exosphere adopted here, it is recommended that a frequency of 1 MHz be considered for low rate data transmission along the lunar surface. It is also recommended that further research be done to capture the descriptive physics of the regolith and the exospheric plasma so that a more complete model can be obtained. This comprehensive theoretical study is based entirely on first principles and the mathematical techniques needed are developed as required; it is self-contained and should not require the use of outside resources for its understanding.

  5. Regolith Advanced Surface Systems Operations Robot (RASSOR)

    NASA Technical Reports Server (NTRS)

    Mueller, Robert P.; Smith, Jonathan D.; Cox, Rachel E.; Schuler, Jason M.; Ebert, Tom; Nick, Andrew J.

    2012-01-01

    Regolith is abundant on extra-terrestrial surfaces and is the source of many resources such as oxygen, hydrogen, titanium, aluminum, iron, silica and other valuable materials, which can be used to make rocket propellant, consumables for life support, radiation protection barrier shields, landing pads, blast protection berms, roads, habitats and other structures and devices. Recent data from the Moon also indicates that there are substantial deposits of water ice in permanently shadowed crater regions and possibly under an over burden of regolith. The key to being able to use this regolith and acquire the resources, is being able to manipulate it with robotic excavation and hauling machinery that can survive and operate in these very extreme extra-terrestrial surface environments. In addition, the reduced gravity on the Moon, Mars, comets and asteroids poses a significant challenge in that the necessary reaction force for digging cannot be provided by the robot's weight as is typically done on Earth. Space transportation is expensive and limited in capacity, so small, lightweight payloads are desirable, which means large traditional excavation machines are not a viable option. A novel, compact and lightweight excavation robot prototype for manipulating, excavating, acquiring, hauling and dumping regolith on extra-terrestrial surfaces has been developed and tested. Lessons learned and test results will be presented including digging in a variety of lunar regolith simulant conditions including frozen regolith mixed with water ice.

  6. Deep dielectric charging of the lunar regolith within permanently shadowed regions

    NASA Astrophysics Data System (ADS)

    Jordan, A.; Stubbs, T. J.; Joyce, C. J.; Schwadron, N.; Smith, S. S.; Spence, H.; Wilson, J. K.

    2013-12-01

    Galactic cosmic rays (GCRs) and solar energetic particles (SEPs) can penetrate within the lunar regolith, causing deep dielectric charging. The discharging timescale depends on the regolith's electrical conductivity and permittivity. In permanently shadowed regions (PSRs) near the lunar poles, this timescale is on the order of a lunation (~20 days). To estimate the resulting electric fields within the regolith, we develop a data-driven, one-dimensional, time-dependent model. For model inputs, we use GCR data from the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) on board the Lunar Reconnaissance Orbiter (LRO) and SEP data from the Electron, Proton, and Alpha Monitor (EPAM) on the Advanced Composition Explorer (ACE). We find that, during the recent solar minimum, GCRs create persistent electric fields up to 700 V/m. We also find that large SEP events create sporadic but strong fields (>10^6 V/m) that may induce dielectric breakdown. Meteoritic gardening limits the amount of time the regolith can spend close enough to the surface to be charged by SEPs, and we find that the gardened regolith within PSRs has likely experienced >10^6 breakdown-inducing events. Since dielectric breakdown typically creates cracks along the boundaries of changes in dielectric constant, we predict repeated breakdown to have fragmented a fraction of the regolith within PSRs into its mineralogical components.

  7. Rock fragment distributions and regolith evolution in the Ouachita Mountains, Arkansas, USA

    Treesearch

    Jonathan D. Phillips; Ken Luckow; Daniel A. Marion; Kristin R. Adams

    2005-01-01

    Rock fragments in the regolith are a persistent property that reflects the combined influences of geologic controls, erosion, deposition, bioturbation, and weathering. The distribution of rock fragments in regoliths of the Ouachita Mountains, Arkansas, shows that sandstone fragments are common in all layers, even if sandstone is absent in parent material. Shale and...

  8. Tantalo-Niobate from the Apollo-17 Regolith

    NASA Astrophysics Data System (ADS)

    Mokhov, A. V.; Kartashov, P. M.; Rybchuk, A. P.; Gornostaeva, T. A.; Bogatikov, O. A.

    2018-01-01

    Particles of tantalo-niobate of the ferrotantalite-manganotantalite series are discovered for the first time in two lunar regolith fragments delivered by the Apollo-17 mission. Allochtonous and autochtonous mineralization that accompanies tantalo-niobate in the regolith is described. An attempt is made to explain the formation of tantalite in anorthosites of the continental region of the Moon.

  9. The Regolith of 4 Vesta - Inferences from Howardites

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, D. W.; Herrin, J. S.; Cartwright, J. A.

    2011-01-01

    Asteroid 4 Vesta is quite likely the parent asteroid of the howardite, eucrite and diogenite meteorites - the HED clan. Eucrites and diogenites are the products of igneous processes; the former are basaltic composition rocks from flows, and shallow and deep intrusive bodies, whilst the latter are cumulate orthopyroxenites thought to have formed deep in the crust. Impact processes have excavated these materials and mixed them into a suite of polymict breccias. Howardites are polymict breccias composed mostly of clasts and mineral fragments of eucritic and diogenitic parentage, with neither end-member comprising more than 90% of the rock. Early work interpreted howardites as representing the lithified regolith of their parent asteroid. Recently, howardites have been divided into two subtypes; fragmental howardites, being a type of non-regolithic polymict breccia, and regolithic howardites, being lithified remnants of the active regolith of 4 Vesta. We are in the thralls of a collaborative investigation of the record of impact mixing contained within howardites, which includes studies of their mineralogy, petrology, bulk rock compositions, and bulk rock and clast noble gas contents. One goal of our investigation is to test the hypothesis that some howardites represent breccias formed from an ancient, well-mixed regolith on Vesta. Another is to use our results to further understand regolith processing on differentiated asteroids as compared to what has been learned from the Moon. We have made petrographic observations and electron microprobe analyses on 21 howardites and 3 polymict eucrites. We have done bulk rock analyses using X-ray fluorescence spectrometry and are completing inductively coupled plasma mass spectrometry analyses. Here, we discuss our petrologic and bulk compositional results in the context of regolith formation. Companion presentations describe the noble gas results and compositional studies of low-Ca pyroxene clasts.

  10. Composition and petrology of HED polymict breccias: The regolith of (4) Vesta

    NASA Astrophysics Data System (ADS)

    Mittlefehldt, David W.; Herrin, Jason S.; Quinn, Julie E.; Mertzman, Stanley A.; Cartwright, Julia A.; Mertzman, Karen R.; Peng, Zhan X.

    2013-11-01

    We have done petrologic and compositional studies on a suite of polymict eucrites and howardites to better understand regolith processes on their parent asteroid, which we accept is (4) Vesta. Taking into account noble gas results from companion studies, we interpret five howardites to represent breccias assembled from the true regolith: Elephant Moraine (EET) 87513, Grosvenor Mountains (GRO) 95535, GRO 95602, Lewis Cliff (LEW) 85313, and Meteorite Hills (MET) 00423. We suggest that EET 87503 is paired with EET 87513, and thus is also regolithic. Pecora Escarpment (PCA) 02066 is dominated by melt-matrix clasts, which may have been formed from true regolith by impact melting. These meteorites display a range in eucrite:diogenite mixing ratio from 55:45 to 76:24. There is no correlation between degree of regolith character and Ni content. The Ni contents of howardite, eucrite, and diogenites (HEDs) are mostly controlled by the distribution of coarse chondritic clasts and metal grains, which in some cases resulted from individual, low-velocity accretion events, rather than extensive regolith gardening. Trace element compositions indicate that the mafic component of HED polymict breccias is mostly basalt similar to main-group eucrites; Stannern-trend basaltic debris is less common. Pyroxene compositions show that some trace element-rich howardites contain abundant debris from evolved basalts, and that cumulate gabbro debris is present in some breccias. The scale of heterogeneity varies considerably; regolithic howardite EET 87513 is more homogeneous than fragmental howardite Queen Alexandra Range (QUE) 97001. Individual samples of a given howardite can have different compositions even at roughly 5 g masses, indicating that obtaining representative meteorite compositions requires multiple or large samples.

  11. Experimental Determination of in Situ Utilization of Lunar Regolith for Thermal Energy Storage

    NASA Technical Reports Server (NTRS)

    Richter, Scott W.

    1993-01-01

    A Lunar Thermal Energy from Regolith (LUTHER) experiment has been designed and fabricated at the NASA Lewis Research Center to determine the feasibility of using lunar soil as thermal energy storage media. The experimental apparatus includes an alumina ceramic canister (25.4 cm diameter by 45.7 cm length) which contains simulated lunar regolith, a heater (either radiative or conductive), 9 heat shields, a heat transfer cold jacket, and 19 type B platinum rhodium thermocouples. The simulated lunar regolith is a basalt, mined and processed by the University of Minnesota, that closely resembles the lunar basalt returned to earth by the Apollo missions. The experiment will test the effects of vacuum, particle size, and density on the thermophysical properties of the regolith. The properties include melt temperature (range), specific heat, thermal conductivity, and latent heat of storage. Two separate tests, using two different heaters, will be performed to study the effect of heating the system using radiative and conductive heat transfer. The physical characteristics of the melt pattern, material compatibility of the molten regolith, and the volatile gas emission will be investigated by heating a portion of the lunar regolith to its melting temperature (1435 K) in a 10(exp -4) pascal vacuum chamber, equipped with a gas spectrum analyzer. A finite differencing SINDA model was developed at NASA Lewis Research Center to predict the performance of the LUTHER experiment. The analytical results of the code will be compared with the experimental data generated by the LUTHER experiment. The code will predict the effects of vacuum, particle size, and density has on the heat transfer to the simulated regolith.

  12. Simulation of the lunar surface emission and inversion of the lunar regolith thickness using fusion of optical and microwave remote sensing data

    NASA Astrophysics Data System (ADS)

    Jin, Y.-Q.

    begin table htbp begin center begin tabular p 442pt hline A correspondence of the lunar regolith layer thickness to the lunar digital elevation mapping DEM is presented to construct the global distribution of lunar regolith layer thickness Based on some measurements the physical temperature distribution over the lunar surface is proposed Albedo of the lunar nearside at the wavelengths 0 42 0 65 0 75 0 95 mu m from the telescopic observation is employed to construct the spatial distribution of the FeO TiO 2 on the lunar regolith layer A statistic relationship between the DEM and FeO TiO 2 content of the lunar nearside is then extended to construction of FeO TiO 2 content of the lunar farside Thus the dielectric permittivity of global lunar regolith layer can be determined par Based on all theses conditions brightness temperature of the lunar regolith layer in passive microwave remote sensing which is planned for China s Chang-E lunar project is numerically simulated by a parallel layer model using the fluctuation dissipation theorem par Furthermore taking these simulations as observations an inversion method of the lunar regolith layer thickness is developed by using three- or two-channels brightness temperatures When the FeO TiO 2 content is low and the four channels brightness temperatures in Chang-E project are well distinguishable the regolith layer thickness and physical temperature of the underlying lunar rocky media can be inverted by the three-channels approach When the FeO TiO 2 content is so high that the

  13. Model for radon diffusion through the lunar regolith.

    NASA Technical Reports Server (NTRS)

    Friesen, L. J.; Heymann, D.

    1972-01-01

    Description of a model for radon diffusion through the lunar regolith in which the atom migrates by random walk. The regolith is represented by a system of randomly oriented baffles in which the mean distance which the atom travels between two collisions takes on the role of a mean free path. The effective mean time between two collisions depends on two entities: the actual mean time-of-flight and the mean sticking time on grain surfaces for one collision. The latter depends strongly on the temperature and the heat of adsorption of radon on regolith materials. Both the mean free path as well as the heat of adsorption are either poorly known or unknown for the lunar regolith; hence these quantities are treated as free parameters. Because of the greatly different mean lifetimes against radioactive decay of Rn219, Rn220, and Rn222, the regolith acts as a powerful 'filter' for these species. Rn222 escape is significant (32%) even for a mean free path of 1 micron, a heat of adsorption of 7.0 kcal/mole and a regolith depth of 4 m. Calculations of radon escape from a 4 m thick regolith, using mean free paths of 1, 10, and 80 microns and heats of adsorption of 4.0, 5.2, and 7.0 kcal/mole show that the Rn222/Rn220 escape ratio can be as small as 7.7 and as large as, or larger than 47. The small value of 7.7 is of particular interest, because it is nearly equal to the escape ratio inferred by Turkevich et al. (1970) from their Surveyor 5 results.

  14. The Evolution and Development of the Lunar Regolith and Implications for Lunar Surface Operations and Construction

    NASA Technical Reports Server (NTRS)

    McKay, David

    2009-01-01

    The lunar regolith consists of about 90% submillimeter particles traditionally termed lunar soil. The remainder consists of larger particles ranging up to boulder size rocks. At the lower size end, soil particles in the 10s of nanometer sizes are present in all soil samples. Lunar regolith overlies bedrock which consists of either lava flows in mare regions or impact-produced megaregolith in highland regions. Lunar regolith has been produced over billions of years by a combination of breaking and communition of bedrock by meteorite bombardment coupled with a variety of complex space weathering processes including solar wind implantation, solar flare and cosmic ray bombardment with attendant radiation damage, melting, vaporization, and vapor condensation driven by impact, and gardening and turnover of the resultant soil. Lunar regolith is poorly sorted compared to most terrestrial soils, and has interesting engineering properties including strong grain adhesion, over-compacted soil density, an abundance of agglutinates with sharp corners, and a variety of properties related to soil maturity. The NASA program has supported a variety of engineering test research projects, the production of bricks by solar or microwave sintering, the production of concrete, the in situ sintering and glazing of regolith by microwave, and the extraction of useful resources such as oxygen, hydrogen, iron, aluminum, silicon and other products. Future requirements for a lunar surface base or outpost will include construction of protective berms, construction of paved roadways, construction of shelters, movement and emplacement of regolith for radiation shielding and thermal control, and extraction of useful products. One early need is for light weight but powerful digging, trenching, and regolith-moving equipment.

  15. Evaluations of lunar regolith simulants

    NASA Astrophysics Data System (ADS)

    Taylor, Lawrence A.; Pieters, Carle M.; Britt, Daniel

    2016-07-01

    Apollo lunar regolith samples are not available in quantity for engineering studies with In-Situ Resource Utilization (ISRU). Therefore, with expectation of a return to the Moon, dozens of regolith (soil) simulants have been developed, to some extent a result of inefficient distribution of NASA-sanctioned simulants. In this paper, we review many of these simulants, with evaluations of their short-comings. In 2010, the NAC-PSS committee instructed the Lunar Exploration Advisory Group (LEAG) and CAPTEM (the NASA committee recommending on the appropriations of Apollo samples) to report on the status of lunar regolith simulants. This report is reviewed here-in, along with a list of the plethora of lunar regolith simulants and references. In addition, and importantly, a special, unique Apollo 17 soil sample (70050) discussed, which has many of the properties sought for ISRU studies, should be available in reasonable amounts for ISRU studies.

  16. Considerations Concerning the Development and Testing of In-situ Materials for Martian Exploration

    NASA Technical Reports Server (NTRS)

    Kim, M.-H. Y.; Heilbronn, L.; Thibeault, S. A.; Simonsen, L. C.; Wilson, J. W.; Chang, K.; Kiefer, R. L.; Maahs, H. G.

    2000-01-01

    Natural Martian surface materials are evaluated for their potential use as radiation shields for manned Mars missions. The modified radiation fluences behind various kinds of Martian rocks and regolith are determined by solving the Boltzmann equation using NASA Langley s HZETRN code along with the 1977 Solar Minimum galactic cosmic ray environmental model. To make structural shielding composite materials from constituents of the Mars atmosphere and from Martian regolith for Martian surface habitats, schemes for synthesizing polyimide from the Mars atmosphere and for processing Martian regolith/polyimide composites are proposed. Theoretical predictions of the shielding properties of these composites are computed to assess their shielding effectiveness. Adding high-performance polymer binders to Martian regolith to enhance structural properties enhances the shielding properties of these composites because of the added hydrogenous constituents. Laboratory testing of regolith simulant/polyimide composites is planned to validate this prediction.

  17. Production of Oxygen from Lunar Regolith using Molten Oxide Electrolysis

    NASA Technical Reports Server (NTRS)

    Sibille, Laurent; Sadoway, Donald R.; Sirk, Aislinn; Tripathy, Prabhat; Melendez, Orlando; Standish, Evan; Dominquez, Jesus A.; Stefanescu, Doru M.; Curreri, Peter A.; Poizeau, Sophie

    2009-01-01

    This slide presentation reviews the possible use of molten oxide electrolysis to extract oxygen from the Lunar Regolith. The presentation asserts that molten regolith electrolysis has advanced to be a useful method for production of oxygen and metals in situ on the Moon. The work has demonstrated an 8 hour batch of electrolysis at 5 amps using Iridium inert anodes.

  18. Lithologic Diversity in Lunar Regolith: Lessons for Future Lunar Exploration Strategies with Application to South Pole-Aitken Basin

    NASA Technical Reports Server (NTRS)

    Jolliff, B. L.; Haskin, L. A.; Gillis, J. J.; Korotev, R. L.; Zeigler, R. A.

    2002-01-01

    Diversity of rock fragments in individual regolith samples from Apollo sites and inferred regolith stratigraphy from large craters and basins in the South Pole-Aitken region are used to assess the value of a single-point sample from the SPA basin. Additional information is contained in the original extended abstract.

  19. Measuring the Shock Stage of Asteroid Regolith Grains by Electron Back-Scattered Diffraction

    NASA Technical Reports Server (NTRS)

    Zolensky, Michael; Martinez, James; Sitzman, Scott; Mikouchi, Takashi; Hagiya, Kenji; Ohsumi, Kazumasa; Terada, Yasuko; Yagi, Naoto; Komatsu, Mutsumi; Ozawa, Hikaru; hide

    2018-01-01

    We have been analyzing Itokawa samples in order to definitively establish the degree of shock experienced by the regolith of asteroid Itokawa, and to devise a bridge between shock determinations by standard light optical petrography, crystal structures as determined by electron and X-ray diffraction. These techniques would then be available for samples returned from other asteroid regoliths.

  20. Comparison of Martian Meteorites and Martian Regolith as Shield Materials for Galactic Cosmic Rays

    NASA Technical Reports Server (NTRS)

    Kim, Myung-Hee Y.; Thibeault, Sheila A.; Simonsen, Lisa C.; Wilson, John W.

    1998-01-01

    Theoretical calculations of radiation attenuation due to energetic galactic cosmic rays behind Martian rock and Martian regolith material have been made to compare their utilization as shields for advanced manned missions to Mars because the detailed chemical signature of Mars is distinctly different from Earth. The modified radiation fields behind the Martian rocks and the soil model were generated by solving the Boltzmann equation using a HZETRN system with the 1977 Solar Minimum environmental model. For the comparison of the attenuation characteristics, dose and dose equivalent are calculated for the five different subgroups of Martian rocks and the Martian regolith. The results indicate that changes in composition of subgroups of Martian rocks have negligible effects on the overall shielding properties because of the similarity of their constituents. The differences for dose and dose equivalent of these materials relative to those of Martian regolith are within 0.5 and 1 percent, respectively. Therefore, the analysis of Martian habitat construction options using in situ materials according to the Martian regolith model composition is reasonably accurate. Adding an epoxy to Martian regolith, which changes the major constituents of the material, enhances shielding properties because of the added hydrogenous constituents.

  1. The Rate of Dielectric Breakdown Weathering of Lunar Regolith in Permanently Shadowed Regions

    NASA Technical Reports Server (NTRS)

    Jordan, A. P.; Stubbs, T. J.; Wilson, J. K.; Schwadron, N. A.; Spence, H. E.

    2016-01-01

    Large solar energetic particle events may cause dielectric breakdown in the upper 1 mm of regolith in permanently shadowed regions (PSRs). We estimate how the resulting breakdown weathering compares to meteoroid impact weathering. Although the SEP event rates measured by the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) on the Lunar Reconnaissance Orbiter (LRO) are too low for breakdown to have significantly affected the regolith over the duration of the LRO mission, regolith gardened by meteoroid impacts has been exposed to SEPs for approx.10(exp 6 yr. Therefore, we estimate that breakdown weathering's production rate of vapor and melt in the coldest PSRs is up to 1.8-3. 5 ×10(exp -7) kg/sq m/yr, which is comparable to that produced by meteoroid impacts. Thus, in PSRs, up to 10-25% of the regolith may have been melted or vaporized by dielectric breakdown. Breakdown weathering could also be consistent with observations of the increased porosity ("fairy castles") of PSR regolith. We also show that it is con- ceivable that breakdown-weathered material is present in Apollo soil samples. Consequently, breakdown weathering could be an important process within PSRs, and it warrants further investigation.

  2. The rate of dielectric breakdown weathering of lunar regolith in permanently shadowed regions

    NASA Astrophysics Data System (ADS)

    Jordan, A. P.; Stubbs, T. J.; Wilson, J. K.; Schwadron, N. A.; Spence, H. E.

    2017-02-01

    Large solar energetic particle events may cause dielectric breakdown in the upper 1 mm of regolith in permanently shadowed regions (PSRs). We estimate how the resulting breakdown weathering compares to meteoroid impact weathering. Although the SEP event rates measured by the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) on the Lunar Reconnaissance Orbiter (LRO) are too low for breakdown to have significantly affected the regolith over the duration of the LRO mission, regolith gardened by meteoroid impacts has been exposed to SEPs for ∼106 yr. Therefore, we estimate that breakdown weathering's production rate of vapor and melt in the coldest PSRs is up to 1.8 - 3.5 ×10-7 kg m-2 yr-1 , which is comparable to that produced by meteoroid impacts. Thus, in PSRs, up to 10-25% of the regolith may have been melted or vaporized by dielectric breakdown. Breakdown weathering could also be consistent with observations of the increased porosity ("fairy castles") of PSR regolith. We also show that it is conceivable that breakdown-weathered material is present in Apollo soil samples. Consequently, breakdown weathering could be an important process within PSRs, and it warrants further investigation.

  3. Geographic information system datasets of regolith-thickness data, regolith-thickness contours, raster-based regolith thickness, and aquifer-test and specific-capacity data for the Lost Creek Designated Ground Water Basin, Weld, Adams, and Arapahoe Counties, Colorado

    USGS Publications Warehouse

    Arnold, L. Rick

    2010-01-01

    These datasets were compiled in support of U.S. Geological Survey Scientific-Investigations Report 2010-5082-Hydrogeology and Steady-State Numerical Simulation of Groundwater Flow in the Lost Creek Designated Ground Water Basin, Weld, Adams, and Arapahoe Counties, Colorado. The datasets were developed by the U.S. Geological Survey in cooperation with the Lost Creek Ground Water Management District and the Colorado Geological Survey. The four datasets are described as follows and methods used to develop the datasets are further described in Scientific-Investigations Report 2010-5082: (1) ds507_regolith_data: This point dataset contains geologic information concerning regolith (unconsolidated sediment) thickness and top-of-bedrock altitude at selected well and test-hole locations in and near the Lost Creek Designated Ground Water Basin, Weld, Adams, and Arapahoe Counties, Colorado. Data were compiled from published reports, consultant reports, and from lithologic logs of wells and test holes on file with the U.S. Geological Survey Colorado Water Science Center and the Colorado Division of Water Resources. (2) ds507_regthick_contours: This dataset consists of contours showing generalized lines of equal regolith thickness overlying bedrock in the Lost Creek Designated Ground Water Basin, Weld, Adams, and Arapahoe Counties, Colorado. Regolith thickness was contoured manually on the basis of information provided in the dataset ds507_regolith_data. (3) ds507_regthick_grid: This dataset consists of raster-based generalized thickness of regolith overlying bedrock in the Lost Creek Designated Ground Water Basin, Weld, Adams, and Arapahoe Counties, Colorado. Regolith thickness in this dataset was derived from contours presented in the dataset ds507_regthick_contours. (4) ds507_welltest_data: This point dataset contains estimates of aquifer transmissivity and hydraulic conductivity at selected well locations in the Lost Creek Designated Ground Water Basin, Weld, Adams, and Arapahoe Counties, Colorado. This dataset also contains hydrologic information used to estimate transmissivity from specific capacity at selected well locations. Data were compiled from published reports, consultant reports, and from well-test records on file with the U.S. Geological Survey Colorado Water Science Center and the Colorado Division of Water Resources.

  4. Optimization of Martian regolith and ultra-high molecular weight polyethylene composites for radiation shielding and habitat structures

    NASA Astrophysics Data System (ADS)

    Wilkins, Richard; Gersey, Brad; Baburaj, Abhijit; Barnett, Milan; Zhou, Xianren

    2012-07-01

    In preparation for long duration missions to the moon, Mars or, even near earth asteroids, one challenge, amongst many others, that the space program faces is shielding against space radiation. It is difficult to effectively shield all sources of space radiation because of the broad range of types and high energies found in space, so the most important goal is to minimize the damaging effects that may occur to humans and electronics during long duration space flight. For a long duration planetary habitat, a shielding option is to use in situ resources such as the native regolith. A possible way to utilize regolith on a planet is to combine it with a binder to form a structural material that also exhibits desirable shielding properties. In our studies, we explore Martian regolith and ultra-high molecular weight polyethylene (UHMWPE) composites. We selected UHMWPE as the binder in our composites due to its high hydrogen content; a desirable characteristic for shielding materials in a space environment. Our initial work has focused on the process of developing the right ratio of simulated Martian regolith and UHMWPE to yield the best results in material endurance and strength, while retaining good shielding characteristics. Another factor in our optimization process is to determine the composite ratio that minimizes the amount of ex situ UHMWPE while retaining desirable structural and shielding properties. This consideration seeks to minimize mission weight and costs. Mechanical properties such as tensile strength of the Martian regolith/UHMWPE composite as a function of its grain size, processing parameters, and different temperature variations used are discussed. The radiation shielding effectiveness of loose mixtures of Martian regolith/ UHMWPE is evaluated using a 200 MeV proton beam and a tissue equivalent proportional counter. Preliminary results show that composites with an 80/20 ratio percent weight of regolith to UHMWPE can be fabricated with potentially useful structural strength. I n addition, Martian regolith, while not as efficient as polyethylene at reducing proton energy as a function of shield thickness, compares well with polyethylene at shielding the 200 MeV protons. These preliminary results indicate that native Martian regolith has promising properties as a habitat material for future human missions. Future work studying the shielding effectiveness and radiation tolerance will also be discussed.

  5. Ceramics for Molten Materials Containment, Transfer and Handling on the Lunar Surface

    NASA Technical Reports Server (NTRS)

    Standish, Evan; Stefanescu, Doru M.; Curreri, Peter A.

    2009-01-01

    As part of a project on Molten Materials Transfer and Handling on the Lunar Surface, molten materials containment samples of various ceramics were tested to determine their performance in contact with a melt of lunar regolith simulant. The test temperature was 1600 C with contact times ranging from 0 to 12 hours. Regolith simulant was pressed into cylinders with the approximate dimensions of 1.25 dia x 1.25cm height and then melted on ceramic substrates. The regolith-ceramic interface was examined after processing to determine the melt/ceramic interaction. It was found that the molten regolith wetted all oxide ceramics tested extremely well which resulted in chemical reaction between the materials in each case. Alumina substrates were identified which withstood contact at the operating temperature of a molten regolith electrolysis cell (1600 C) for eight hours with little interaction or deformation. This represents an improvement over alumina grades currently in use and will provide a lifetime adequate for electrolysis experiments lasting 24 hours or more. Two types of non-oxide ceramics were also tested. It was found that they interacted to a limited degree with the melt resulting in little corrosion. These ceramics, Sic and BN, were not wetted as well as the oxides by the melt, and so remain possible materials for molten regolith handling. Tests wing longer holding periods and larger volumes of regolith are necessary to determine the ultimate performance of the tested ceramics.

  6. Thermophysical Property Models for Lunar Regolith

    NASA Technical Reports Server (NTRS)

    Schreiner, Samuel S.; Dominguez, Jesus A.; Sibille, Laurent; Hoffman, Jeffrey A.

    2015-01-01

    We present a set of models for a wide range of lunar regolith material properties. Data from the literature are t with regression models for the following regolith properties: composition, density, specific heat, thermal conductivity, electrical conductivity, optical absorption length, and latent heat of melting/fusion. These models contain both temperature and composition dependencies so that they can be tailored for a range of applications. These models can enable more consistent, informed analysis and design of lunar regolith processing hardware. Furthermore, these models can be utilized to further inform lunar geological simulations. In addition to regression models for each material property, the raw data is also presented to allow for further interpretation and fitting as necessary.

  7. Space Weathering of Itokawa Particles: Implications for Regolith Evolution

    NASA Technical Reports Server (NTRS)

    Berger, Eve L.; Keller, Lindsay P.

    2015-01-01

    Space weathering processes such as solar wind irradiation and micrometeorite impacts are known to alter the the properties of regolith materials exposed on airless bodies. The rates of space weathering processes however, are poorly constrained for asteroid regoliths, with recent estimates ranging over many orders of magnitude. The return of surface samples by JAXA's Hayabusa mission to asteroid 25143 Itokawa, and their laboratory analysis provides "ground truth" to anchor the timescales for space weathering processes on airless bodies. Here, we use the effects of solar wind irradiation and the accumulation of solar flare tracks recorded in Itokawa grains to constrain the rates of space weathering and yield information about regolith dynamics on these timescales.

  8. Signatures of Volatiles in the Lunar Proton Albedo

    NASA Technical Reports Server (NTRS)

    Schwadron, N. A.; Wilson, J. K.; Looper, M. D.; Jordan, A. P.; Spence, H. E.; Blake, J. B.; Case, A. W.; Iwata, Y.; Kasper, J. C.; Farrell, W. M.; hide

    2015-01-01

    We find evidence for hydrated material in the lunar regolith using "albedo protons" measured with the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) on the Lunar Reconnaissance Orbiter (LRO). Fluxes of these albedo protons, which are emitted from the regolith due to steady bombardment by high energy radiation (Galactic Cosmic Rays), are observed to peak near the poles, and are inconsistent with the latitude trends of heavy element enrichment (e.g., enhanced Fe abundance). The latitudinal distribution of albedo protons anti-correlates with that of epithermal or high energy neutrons. The high latitude enhancement may be due to the conversion of upward directed secondary neutrons from the lunar regolith into tertiary protons due to neutron-proton collisions in hydrated regolith that is more prevalent near the poles. The CRaTER instrument may thus provide important measurements of volatile distributions within regolith at the Moon and potentially, with similar sensors and observations, at other bodies within the Solar System.

  9. In quest of lunar regolith breccias of exotic provenance - A uniquely anorthositic sample from the Fra Mauro (Apollo 14) highlands

    NASA Technical Reports Server (NTRS)

    Jerde, Eric A.; Warren, Paul H.; Morris, Richard V.

    1990-01-01

    Bulk compositions of 21 Apollo regolith breccias were determined using an INAA procedure modified from that of Kallemeyn et al. (1989). With one major exception, namely, the 14076,1 sample, the regolith breccias analyzed were found to be not significantly different from the surfaces from which they were collected. In contrast, the 14076,1 sample from the Fra Mauro (Apollo 14) region is a highly anorthositic regolith breccia from a site where anorthosites are extremely scarce. The sample's composition resembles soils from the Descartes (Apollo 16) highlands. However, the low statistical probability for long-distance horizontal transport by impact cratering, together with the relatively high contents of imcompatible elements in 14076,1 suggest that this regolith breccia originated within a few hundred kilometers of the Apollo 14 site. Its compositional resemblance to ferroan anorthosite strengthens the hypothesis that ferroan anorthosite originated as the flotation crust of a global magmasphere.

  10. Toward a Suite of Standard Lunar Regolith Simulants for NASA's Lunar Missions: Recommendations of the 2005 Workshop of Lunar Regolith Simulant Materials

    NASA Technical Reports Server (NTRS)

    Schlagheck, R. A.; Sibille, L.; Carpenter, P.

    2005-01-01

    As NASA turns its exploration ambitions towards the Moon once again, the research and development of new technologies for lunar operations face the challenge of meeting the milestones of a fast-pace schedule, reminiscent of the 1960's Apollo program. While the lunar samples returned by the Apollo and Luna missions have revealed much about the Moon, these priceless materials exist in too scarce quantities to be used for technology development and testing. The need for mineral materials chosen to simulate the characteristics of lunar regoliths is a pressing issue that is being addressed today through the collaboration of scientists, engineers and NASA program managers. The issue of reproducing the properties of lunar regolith for research and technology development purposes was addressed by the recently held Workshop on Lunar Regolith Simulant Materials at Marshall Space Flight Center. The conclusions from the workshop and considerations concerning the feasibility (both technical and programmatic) of producing such materials will be presented here.

  11. Lunar Regolith Excavation Student Competition Design

    NASA Technical Reports Server (NTRS)

    Nething, Julia

    2009-01-01

    The Surface Systems team is working to learn about lunar regolith and how we can use it as a source of air, water, and fuel for spacecrafts. However, excavation of this valuable regolith is difficult because the robot has to conform to many specifications (mass limit, efficiency level, etc.). NASA has therefore decided to include college students and companies in the search to create the best robot by making it into a competition.

  12. Challenges in Characterizing Low-Temperature Regolith Properties

    NASA Technical Reports Server (NTRS)

    Swanger, Adam Michael; Mantovani, James G.

    2014-01-01

    The success or failure of in-situ resource utilization for planetary surface exploration--be it for scientific, colonization or commercialization purposes--relies heavily on the ability to design and implement systems which effectively process the associated regolith and exploit its benefits. In most cases this challenge necessarily includes the characterization of low-temperature (cryogenic) properties; as many celestial destinations of interest, such as the moon, Mars and asteroids, have little or no atmosphere to help sustain the consistently "high" surface temperatures seen on planets such as Earth, and therefore can experience permanent cryogenic temperatures or dramatic cyclical changes. Characterization of physical properties (such as specific heat, thermal and electrical conductivity, etc.) over the entire temperature profile is undoubtedly an important piece of the puzzle; however, the impact on mechanical properties due to the introduction of icy deposit must also be explored in order to devise effective and robust excavation technologies. Currently the Granular Mechanics and Regolith Operations Lab and the Cryogenics Test Lab at NASA Kennedy Space Center are developing technologies and experimental methods to address these challenges and aid in the characterization of physical and mechanical properties of regolith at cryogenic temperatures. This presentation will review the current state of knowledge concerning lunar regolith at low temperature including that of icy regolith.

  13. Consortium study of the unusual H chondrite regolith breccia, Noblesville

    NASA Technical Reports Server (NTRS)

    Lipschutz, Michael E.; Wolf, Stephen F.; Vogt, Stephan; Michlovich, Edward; Lindstrom, Marilyn M.; Zolensky, Michael E.; Mittlefehldt, David W.; Satterwhite, Cecilia; Schultz, Ludolf; Loeken, Thomas

    1993-01-01

    The Noblesville meteorite is a genomict, regolith breccia (H6 clasts in H4 matrix). Moessbauer analysis confirms that Noblesville is unusually fresh, not surprising in view of its recovery immediately after its fall. It resembles 'normal' H4-6 chondrites in its chemical composition and induced thermoluminescence (TL) levels. Thus, at least in its contents of volatile trace elements, Noblesville differs from other H chondrite, class A regolith breccias. Noblesville's small pre-atmospheric mass and fall near solar maximum and/or its peculiar orbit (with perihelion less than 0.8 AU as shown by natural TL intensity) may partly explain its levels of cosmogenic radionuclides. Its cosmic ray exposure age of about 44 Ma is long, is equalled or exceeded by less than 3 percent of all H chondrites, and also differs from the 33 +/- 3 Ma mean exposure age peak of other H chondrite regolith breccias. While Noblesville is now among the chondritic regolithic breccias richest in solar gases, elemental ratios indicate some loss, especially of He, perhaps by impacts in the regolith that heated individual grains. While general shock-loading levels in Noblesville did not exceed 4 GPa, individual clasts record shock levels of 5-10 GPa, doubtless acquired prior to lithification of the whole-rock meteoroid.

  14. Lunar regolith thickness determination from 3D morphology of small fresh craters

    NASA Astrophysics Data System (ADS)

    Di, Kaichang; Sun, Shujuan; Yue, Zongyu; Liu, Bin

    2016-03-01

    The lunar regolith can provide critical information about the Moon and the space environment. In the study of lunar regolith, thickness is one of its most important parameters because of the significance in estimating the relative geologic age and the quantities of solar wind implanted volatiles. In this research, an improved morphological method for determining the lunar regolith thickness is proposed by directly measuring the distance from the lunar ground surface to the floor (flat-bottomed and central-mound craters) or bench (concentric craters) of indicative small fresh craters. The pre-impact ground surface is first modeled with crater edge points through plane fitting, avoiding crater ejecta. Then the lunar regolith thickness is calculated as the distance between the modeled ground surface and the crater floor or bench. The method has been verified at the landing sites of Chang'E-3 rover with high-resolution stereo images from Chang'E-2 orbiter, and the landing sites of Apollo 11, 12, 14, 15, 16, and 17 missions with high-resolution Lunar Reconnaissance Orbiter DEM data. All the results are in good agreement with results from in-situ measurements, demonstrating the reliability of the proposed method. This method can be applied to estimate lunar regolith thickness where high-precision topographic data is available.

  15. Microwave Permittivity and Permeability Measurement on Lunar Soils

    NASA Technical Reports Server (NTRS)

    Barmatz, Martin; Steinfeld, David; Begley, Shelley B.; Winterhalter, Daniel; Allen, Carlton

    2011-01-01

    There has been interest in finding ways to process the lunar regolith since the early analyses of lunar samples returned from the Apollo moon missions. This fact has led to proposals for using microwaves to perform in-situ processing of the lunar soil to support future colonization of the moon. More recently, there has been speculation that the excellent microwave absorption of lunar soil came from the nanophase iron content in the regolith. The motivation for the present study was to begin obtaining a more fundamental understanding of the dielectric and magnetic properties of the regolith at microwave frequencies. A major objective of this study was to obtain information that would help answer the question about whether nanophase iron plays a major role in heating lunar soils. These new measurements over a wide frequency range can also determine the magnitude of the dielectric and magnetic absorption and if there are any resonant features that could be used to enhance processing of the regolith in the future. In addition, these microwave measurements would be useful in confirming that new simulants being developed, particularly those containing nanophase iron, would have the correct composition to simulate the lunar regolith. The results of this study suggest that nanophase iron does not play a major role in heating lunar regolith.

  16. The Strata-1 experiment on small body regolith segregation

    NASA Astrophysics Data System (ADS)

    Fries, Marc; Abell, Paul; Brisset, Julie; Britt, Daniel; Colwell, Joshua; Dove, Adrienne; Durda, Dan; Graham, Lee; Hartzell, Christine; Hrovat, Kenneth; John, Kristen; Karrer, Dakotah; Leonard, Matthew; Love, Stanley; Morgan, Joseph; Poppin, Jayme; Rodriguez, Vincent; Sánchez-Lana, Paul; Scheeres, Dan; Whizin, Akbar

    2018-01-01

    The Strata-1 experiment studies the mixing and segregation dynamics of regolith on small bodies by exposing a suite of regolith simulants to the microgravity environment aboard the International Space Station (ISS) for one year. This will improve our understanding of regolith dynamics and properties on small asteroids, and may assist in interpreting analyses of samples from missions to small bodies such as OSIRIS-REx, Hayabusa-1 and -2, and future missions to small bodies. The Strata-1 experiment consists of four evacuated tubes partially filled with regolith simulants. The simulants are chosen to represent models of regolith covering a range of complexity and tailored to inform and improve computational studies. The four tubes are regularly imaged while moving in response to the ambient vibrational environment using dedicated cameras. The imagery is then downlinked to the Strata-1 science team about every two months. Analyses performed on the imagery includes evaluating the extent of the segregation of Strata-1 samples and comparing the observations to computational models. After Strata-1's return to Earth, x-ray tomography and optical microscopy will be used to study the post-flight simulant distribution. Strata-1 is also a pathfinder for the new "1E" ISS payload class, which is intended to simplify and accelerate emplacement of experiments on board ISS.

  17. Simulating regolith ejecta due to gas impingement

    NASA Astrophysics Data System (ADS)

    Chambers, Wesley Allen; Metzger, Philip; Dove, Adrienne; Britt, Daniel

    2016-10-01

    Space missions operating at or near the surface of a planet or small body must consider possible gas-regolith interactions, as they can cause hazardous effects or, conversely, be employed to accomplish mission goals. They are also directly related to a body's surface properties; thus understanding these interactions could provide an additional tool to analyze mission data. The Python Regolith Interaction Calculator (PyRIC), built upon a computational technique developed in the Apollo era, was used to assess interactions between rocket exhaust and an asteroid's surface. It focused specifically on threshold conditions for causing regolith ejecta. To improve this model, and learn more about the underlying physics, we have begun ground-based experiments studying the interaction between gas impingement and regolith simulant. Compressed air, initially standing in for rocket exhaust, is directed through a rocket nozzle at a bed of simulant. We assess the qualitative behavior of various simulants when subjected to a known maximum surface pressure, both in atmosphere and in a chamber initially at vacuum. These behaviors are compared to prior computational results, and possible flow patterns are inferred. Our future work will continue these experiments in microgravity through the use of a drop tower. These will use several simulant types and various pressure levels to observe the effects gas flow can have on target surfaces. Combining this with a characterization of the surface pressure distribution, tighter bounds can be set on the cohesive threshold necessary to maintain regolith integrity. This will aid the characterization of actual regolith distributions, as well as informing the surface operation phase of mission design.

  18. The Lunar Regolith

    NASA Technical Reports Server (NTRS)

    Noble, Sarah

    2009-01-01

    A thick layer of regolith, fragmental and unconsolidated rock material, covers the entire lunar surface. This layer is the result of the continuous impact of meteoroids large and small and the steady bombardment of charged particles from the sun and stars. The regolith is generally about 4-5 m thick in mare regions and 10-15 m in highland areas (McKay et al., 1991) and contains all sizes of material from large boulders to sub-micron dust particles. Below the regolith is a region of large blocks of material, large-scale ejecta and brecciated bedrock, often referred to as the "megaregolith". Lunar soil is a term often used interchangeably with regolith, however, soil is defined as the subcentimeter fraction of the regolith (in practice though, soil generally refers to the submillimeter fraction of the regolith). Lunar dust has been defined in many ways by different researchers, but generally refers to only the very finest fractions of the soil, less than approx.10 or 20 microns. Lunar soil can be a misleading term, as lunar "soil" bears little in common with terrestrial soils. Lunar soil contains no organic matter and is not formed through biologic or chemical means as terrestrial soils are, but strictly through mechanical comminution from meteoroids and interaction with the solar wind and other energetic particles. Lunar soils are also not exposed to the wind and water that shapes the Earth. As a consequence, in contrast to terrestrial soils, lunar soils are not sorted in any way, by size, shape, or chemistry. Finally, without wind and water to wear down the edges, lunar soil grains tend to be sharp with fresh fractured surfaces.

  19. Development of the mare regolith: some model considerations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Quaide, W.; Oberbeck, V.

    1975-05-01

    Mare regolith is fragmental debris of variable thickness that lies upon fractured bedrock. Its origin by impact comminution of primarily local basaltic rocks is widely accepted, but the consequences of such an origin are not appreciated fully. This investigation uses results obtained in an earlier Monte Carlo study by Oberbeck et al. (1973) to shed light on those consequences by evaluating regolith growth and mixing as a function of time. Results reported are for average cases and must be used with caution. The study demonstrates that regolith growth is self regulated and has the same trend and nearly the samemore » terminal growth rates whatever the history of bombardment: rapid initial accumulation followed by diminishing rates of growth. Mixing and all other processes investigated are growth regulated. Mixing increases as growth slows, but never to the extent that the regolith is homogenized. Because the average regolith is never homogenized, products of growth regulated processes are preserved in the stratigraphy. Differences in material properties are to be expected in vertical sections of the regolith, therefore, this model is not sufficiently refined to permit prediction of all possible trends. It does indicate, however, that deeper levels contain thinner depositional units, lesser quantities of meteoritic and exotic components, and more debris derived from shallow levels in the mare basalts than material in near surface layers. Additionally, neutron fluence production is regulated by the growth process, but because rates of growth do not differ much over the last aeon, whatever the total age or early bombardment history, values of surface fluence may be similar in many areas whatever their age. (NL)« less

  20. Evolution and Transport of Water in the Upper Regolith of Mars

    NASA Technical Reports Server (NTRS)

    Hudson, T. L.; Aharonson, O.; Schorghofer, N.; Hecht, M. H.; Bridges, N. T.; Green, J. R.

    2003-01-01

    Long standing theoretical predictions [1-3], as well as recent spacecraft observations [4] indicate that large quantities of ice is present in the high latitudes upper decimeters to meters of the Martian regolith. At shallower depths and warmer locations small amounts of H2O, either adsorbed or free, may be present transiently. An understanding of the evolution of water based on theoretical and experimental considerations of the processes operating at the Martian environment is required. In particular, the porosity, diffusivity, and permeability of soils and their effect on water vapor transport under Mars-like conditions have been estimated, but experimental validation of such models is lacking. Goal: Three related mechanisms may affect water transport in the upper Martian regolith. 1) diffusion along a concentration gradient under isobaric conditions, 2) diffusion along a thermal gradient, which may give rise to a concentration gradient as ice sublimes or molecules desorb from the regolith, and 3) hydraulic flow, or mass motion in response to a pressure gradient. Our combined theoretical and experimental investigation seeks to disentangle these mechanisms and determine which process(es) are dominant in the upper regolith over various timescales. A detailed one-dimensional model of the upper regolith is being created which incorporates water adsorption/ desorption, condensation, porosity, diffusivity, and permeability effects. Certain factors such as diffusivity are difficult to determine theoretically due to the wide range of intrinsic grain properties such as particle sizes, shapes, packing densities, and emergent properties such as tortuosity. An experiment is being designed which will allow us to more accurately determine diffusivity, permeability, and water desorption isotherms for regolith simulants.

  1. SSERVI Analog Regolith Simulant Testbed Facility

    NASA Astrophysics Data System (ADS)

    Minafra, Joseph; Schmidt, Gregory; Bailey, Brad; Gibbs, Kristina

    2016-10-01

    The Solar System Exploration Research Virtual Institute (SSERVI) at NASA's Ames Research Center in California's Silicon Valley was founded in 2013 to act as a virtual institute that provides interdisciplinary research centered on the goals of its supporting directorates: NASA Science Mission Directorate (SMD) and the Human Exploration & Operations Mission Directorate (HEOMD).Primary research goals of the Institute revolve around the integration of science and exploration to gain knowledge required for the future of human space exploration beyond low Earth orbit. SSERVI intends to leverage existing JSC1A regolith simulant resources into the creation of a regolith simulant testbed facility. The purpose of this testbed concept is to provide the planetary exploration community with a readily available capability to test hardware and conduct research in a large simulant environment.SSERVI's goals include supporting planetary researchers within NASA, other government agencies; private sector and hardware developers; competitors in focused prize design competitions; and academic sector researchers.SSERVI provides opportunities for research scientists and engineers to study the effects of regolith analog testbed research in the planetary exploration field. This capability is essential to help to understand the basic effects of continued long-term exposure to a simulated analog test environment.The current facility houses approximately eight tons of JSC-1A lunar regolith simulant in a test bin consisting of a 4 meter by 4 meter area, including dust mitigation and safety oversight.Facility hardware and environment testing scenarios could include, Lunar surface mobility, Dust exposure and mitigation, Regolith handling and excavation, Solar-like illumination, Lunar surface compaction profile, Lofted dust, Mechanical properties of lunar regolith, Surface features (i.e. grades and rocks)Numerous benefits vary from easy access to a controlled analog regolith simulant testbed, and planetary exploration activities at NASA Research Park, to academia and expanded commercial opportunities, as well as public outreach and education opportunities.

  2. LUNAR OUTGASSING, TRANSIENT PHENOMENA, AND THE RETURN TO THE MOON. II. PREDICTIONS AND TESTS FOR OUTGASSING/REGOLITH INTERACTIONS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Crotts, Arlin P. S.; Hummels, Cameron

    2009-12-20

    We follow Paper I with predictions of how gas leaking through the lunar surface could influence the regolith, as might be observed via optical transient lunar phenomena (TLPs) and related effects. We touch on several processes, but concentrate on low and high flow rate extremes, which are perhaps the most likely. We model explosive outgassing for the smallest gas overpressure at the regolith base that releases the regolith plug above it. This disturbance's timescale and affected area are consistent with observed TLPs; we also discuss other effects. For slow flow, escape through the regolith is prolonged by low diffusivity. Water,more » found recently in deep magma samples, is unique among candidate volatiles, capable of freezing between the regolith base and surface, especially near the lunar poles. For major outgassing sites, we consider the possible accumulation of water ice. Over geological time, ice accumulation can evolve downward through the regolith. Depending on gases additional to water, regolith diffusivity might be suppressed chemically, blocking seepage and forcing the ice zone to expand to larger areas, up to km{sup 2} scales, again, particularly at high latitudes. We propose an empirical path forward, wherein current and forthcoming technologies provide controlled, sensitive probes of outgassing. The optical transient/outgassing connection, addressed via Earth-based remote sensing, suggests imaging and/or spectroscopy, but aspects of lunar outgassing might be more covert, as indicated above. TLPs betray some outgassing, but does outgassing necessarily produce TLPs? We also suggest more intrusive techniques from radar to in situ probes. Understanding lunar volatiles seems promising in terms of resource exploitation for human exploration of the Moon and beyond, and offers interesting scientific goals in its own right. Many of these approaches should be practiced in a pristine lunar atmosphere, before significant confusing signals likely to be produced upon humans returning to the Moon.« less

  3. Lunar Outgassing, Transient Phenomena, and the Return to the Moon. II. Predictions and Tests for Outgassing/Regolith Interactions

    NASA Astrophysics Data System (ADS)

    Crotts, Arlin P. S.; Hummels, Cameron

    2009-12-01

    We follow Paper I with predictions of how gas leaking through the lunar surface could influence the regolith, as might be observed via optical transient lunar phenomena (TLPs) and related effects. We touch on several processes, but concentrate on low and high flow rate extremes, which are perhaps the most likely. We model explosive outgassing for the smallest gas overpressure at the regolith base that releases the regolith plug above it. This disturbance's timescale and affected area are consistent with observed TLPs; we also discuss other effects. For slow flow, escape through the regolith is prolonged by low diffusivity. Water, found recently in deep magma samples, is unique among candidate volatiles, capable of freezing between the regolith base and surface, especially near the lunar poles. For major outgassing sites, we consider the possible accumulation of water ice. Over geological time, ice accumulation can evolve downward through the regolith. Depending on gases additional to water, regolith diffusivity might be suppressed chemically, blocking seepage and forcing the ice zone to expand to larger areas, up to km2 scales, again, particularly at high latitudes. We propose an empirical path forward, wherein current and forthcoming technologies provide controlled, sensitive probes of outgassing. The optical transient/outgassing connection, addressed via Earth-based remote sensing, suggests imaging and/or spectroscopy, but aspects of lunar outgassing might be more covert, as indicated above. TLPs betray some outgassing, but does outgassing necessarily produce TLPs? We also suggest more intrusive techniques from radar to in situ probes. Understanding lunar volatiles seems promising in terms of resource exploitation for human exploration of the Moon and beyond, and offers interesting scientific goals in its own right. Many of these approaches should be practiced in a pristine lunar atmosphere, before significant confusing signals likely to be produced upon humans returning to the Moon.

  4. Evaluating the effect of lithology on porosity development in ridgetops in the Appalachian Piedmont

    NASA Astrophysics Data System (ADS)

    Marcon, V.; Gu, X.; Fisher, B.; Brantley, S. L.

    2016-12-01

    Together, chemical and physical processes transform fresh bedrock into friable weathered material. Even in systems where lithology, tectonic history, and climatic history are all known, it is challenging to predict the depth of weathering because the mechanisms that control the rate of regolith formation are not understood. In the Appalachian Piedmont, where rates of regolith formation and erosion are thought to be in a rough steady state, the depth of weathering varies with lithology. The Piedmont provides a controlled natural environment to isolate the effects of lithology on weathering processes so we can start to understand the mechanisms that initiate and drive weathering. Weathering is deepest over feldspathic rocks (schist/granite) with regolith 20-30m thick and thinnest over mafic and ultramafic rocks (diabase/serpentinite) with regolith <5m thick (Pavich et al., 1989). We are exploring both chemical and physical controls on weathering. For example, when regolith thickness is plotted versus fracture toughness of each lithology, regolith thickness generally increases with decreasing fracture toughness. However, serpentinite, a rheologically weak rock, does not follow this trend with thin soils. To understand this observation, physical weathering parameters (porosity, connectivity, and surface area) were evaluated using neutron scattering on Piedmont rocks at different degrees of weathering. Samples of both weathered diabase and serpentinite are dominated by small pores (<0.1micron), whereas pores in schist are characteristically larger (1-10microns). As serpentinite weathers, porosity is created by serpentinization reactions and lost from collapse during weathering. Serpentinite consists of easily weathered hydrous minerals with little quartz. Comparatively, rocks with more quartz (e.g. schist) have a supportive skeleton as the rock weathers. This quartz skeleton could prevent the collapse of pores and result in isovolumetric weathering. Non-isovolumetric weathering limits infiltration of reactive fluids deeper into the rock, minimizing regolith formation in serpentinite due to its lack of a quartz skeleton. Given this, fracture toughness may be an important parameter to consider in terms of predicting regolith thickness.

  5. Modeling of Melt Growth During Carbothermal Processing of Lunar Regolith

    NASA Technical Reports Server (NTRS)

    Balasubramaniam, R.; Gokoglu S.; Hegde, U.

    2012-01-01

    The carbothermal processing of lunar regolith has been proposed as a means to produce carbon monoxide and ultimately oxygen to support human exploration of the moon. In this process, gaseous methane is pyrolyzed as it flows over the hot surface of a molten zone of lunar regolith and is converted to carbon and hydrogen. Carbon gets deposited on the surface of the melt, and mixes and reacts with the metal oxides in it to produce carbon monoxide that bubbles out of the melt. Carbon monoxide is further processed in other reactors downstream to ultimately produce oxygen. The amount of oxygen produced crucially depends on the amount of regolith that is molten. In this paper we develop a model of the heat transfer in carbothermal processing. Regolith in a suitable container is heated by a heat flux at its surface such as by continuously shining a beam of solar energy or a laser on it. The regolith on the surface absorbs the energy and its temperature rises until it attains the melting point. The energy from the heat flux is then used for the latent heat necessary to change phase from solid to liquid, after which the temperature continues to rise. Thus a small melt pool appears under the heated zone shortly after the heat flux is turned on. As time progresses, the pool absorbs more heat and supplies the energy required to melt more of the regolith, and the size of the molten zone increases. Ultimately, a steady-state is achieved when the heat flux absorbed by the melt is balanced by radiative losses from the surface. In this paper, we model the melting and the growth of the melt zone with time in a bed of regolith when a portion of its surface is subjected to a constant heat flux. The heat flux is assumed to impinge on a circular area. Our model is based on an axisymmetric three-dimensional variation of the temperature field in the domain. Heat transfer occurs only by conduction, and effects of convective heat transport are assumed negligible. Radiative heat loss from the surface of the melt and the regolith to the surroundings is permitted. We perform numerical computations to determine the shape and the mass of the melt at steady state and its time evolution. We first neglect the volume change upon melting, and subsequently perform calculations including it. Predictions from our model are compared to test data to determine the effective thermal conductivities of the regolith and the melt that are compatible with the data

  6. A granulometry and secondary mineral fingerprint of chemical weathering in periglacial landscapes and its application to blockfield origins

    NASA Astrophysics Data System (ADS)

    Goodfellow, Bradley W.

    2012-12-01

    A review of published literature was undertaken to determine if there was a fingerprint of chemical weathering in regoliths subjected to periglacial conditions during their formation. If present, this fingerprint would be applied to the question of when blockfields in periglacial landscapes were initiated. These blocky diamicts are usually considered to represent remnants of regoliths that were chemically weathered under a warm, Neogene climate and therefore indicate surfaces that have undergone only a few metres to a few 10s of metres of erosion during the Quaternary. Based on a comparison of clay and silt abundances and secondary mineral assemblages from blockfields, other regoliths in periglacial settings, and regoliths from non-periglacial settings, a fingerprint of chemical weathering in periglacial landscapes was identified. A mobile regolith origin under, at least seasonal, periglacial conditions is indicated where clay(%) ≤ 0.5*silt(%) + 8 across a sample batch. This contrasts with a mobile regolith origin under non-periglacial conditions, which is indicated where clay(%) ≥ 0.5*silt(%) - 6 across a sample batch with clay(%) ≥ 0.5*silt(%) + 8 in at least one sample. A range of secondary minerals, which frequently includes interstratified minerals and indicates high local variability in leaching conditions, is also commonly present in regoliths exposed to periglacial conditions during their formation. Clay/silt ratios display a threshold response to temperature, related to the freezing point of water, but there is little response to precipitation or regolith residence time. Lithology controls clay and silt abundances, which increase from felsic, through intermediate, to mafic compositions, but does not control clay/silt ratios. Use of a sedigraph or Coulter Counter to determine regolith granulometry systematically indicates lower clay abundances and intra-site variability than use of a pipette or hydrometer. In contrast to clay/silt ratios, secondary mineral assemblages vary according to regolith residence time, temperature, and/or precipitation. A microsystems model is invoked as a conceptual framework in which to interpret the concurrent formation of the observed secondary mineral ranges. According to the fingerprint of chemical weathering in periglacial landscapes, there is generally no evidence of blockfield origins under warm Neogene climates. Nearly all blockfields appear to be a product of Quaternary physical and chemical weathering. A more dominant role for periglacial processes in further bevelling elevated, low relief, non-glacial surface remnants in otherwise glacially eroded landscapes is therefore indicated.

  7. Experimental Testing and Modeling of a Pneumatic Regolith Delivery System for ISRU

    NASA Technical Reports Server (NTRS)

    Santiago-Maldonado, Edgardo; Dominquez, Jesus A.; Mantovani, James G.

    2011-01-01

    Excavating and transporting planetary regolith are examples of surface activities that may occur during a future space exploration mission to a planetary body. Regolith, whether it is collected on the Moon, Mars or even an asteroid, consists of granular minerals, some of which have been identified to be viable resources that can be mined and processed chemically to extract useful by-products, such as oxygen, water, and various metals and metal alloys. Even the depleted "waste" material from such chemical processes may be utilized later in the construction of landing pads and protective structures at the site of a planetary base. One reason for excavating and conveying planetary regolith is to deliver raw regolith material to in-situ resource utilization (ISRU) systems. The goal of ISRU is to provide expendable supplies and materials at the planetary destination, if possible. An in-situ capability of producing mission-critical substances such as oxygen will help to extend the mission and its success, and will greatly lower the overall cost of a mission by either eliminating, or significantly reducing, the need to transport the same expendable materials from the Earth. In order to support the goals and objectives of present and future ISRU projects, NASA seeks technology advancements in the areas of regolith conveying. Such systems must be effective, efficient and provide reliable performance over long durations while being exposed to the harsh environments found on planetary surfaces. These conditions include contact with very abrasive regolith particulates, exposure to high vacuum or dry (partial) atmospheres, wide variations in temperature, reduced gravity, and exposure to space radiation. Regolith conveying techniques that combine reduced failure modes and low energy consumption with high material transfer rates will provide significant value for future space exploration missions to the surfaces of the moon, Mars and asteroids. Pneumatic regolith conveying has demonstrated itself to be a viable delivery system through testing under terrestrial and reduced gravity conditions in recent years. Modeling and experimental testing have been conducted at NASA Kennedy Space Center to study and advance pneumatic planetary regolith delivery systems in support of NASA's ISRU project. The goal of this work is to use the model to predict solid-gas flow patterns in reduced gravity environments for ISRU inlet gas line allowing the eductor inlet gas flow to vary and depend on the flow pattern developed at the eductor as inferred by the experimental observations.

  8. Regolith-Derived Heat Shield for Planetary Body Entry and Descent System with In-Situ Fabrication

    NASA Technical Reports Server (NTRS)

    Hogue, Michael D.; Mueller, Robert P.; Sibille, Laurent; Hintze, Paul E.; Rasky, Daniel J.

    2012-01-01

    High-mass planetary surface access is one of NASA's Grand Challenges involving entry, descent, and landing (EDL). Heat shields fabricated in-situ can provide a thermal protection system for spacecraft that routinely enter a planetary atmosphere. Fabricating the heat shield from extraterrestrial regolith will avoid the costs of launching the heat shield mass from Earth. This project will investigate three methods to fabricate heat shield using extraterrestrial regolith.

  9. Investigating the Sources and Timing of Projectiles Striking the Lunar Surface

    NASA Technical Reports Server (NTRS)

    Joy, K. H.; Kring, D. A.; Zolensky, M. E.; McKay, D. S.; Ross, D. K.

    2011-01-01

    The lunar surface is exposed to bombardment by asteroids, comets, and debris from them. Surviving fragments of those projectiles in the lunar regolith provide a direct measure of the sources of exogenous material delivered to the Moon. Con-straining the temporal flux of their delivery will directly address key questions about the bombardment history of the inner Solar System. Regolith breccias, which are consolidated samples of the lunar regolith, were closed to further impact processing at the time they were assembled into rocks [1]. They are, therefore, time capsules of impact bombardment at different times through lunar history. Here we investigate the impact archive preserved in the Apollo 16 regolith breccias and compare this record to evidence of projectile species in other lunar samples.

  10. Fractionation of nitrogen isotopic on Mars: The role of the regolith as a buffer

    NASA Technical Reports Server (NTRS)

    Zent, A. P.; Quinn, R. C.; Jakosky, B. M.

    1994-01-01

    We have measured the adsorption of molecular nitrogen (N2) on palagonite, and modeled the adsorbed nitrogen inventory on the martian regolith. We were motivated by the fact that models of isotopic evolution predict stronger N2 fractionation than reported by Viking. Possible scenarios for reconciling models with the observation include a heavy CO2 atmosphere early in the planet's history, continued outgassing of N2 throughout the history of Mars, or a substantial adsorbed inventory. In this paper we investigate the plausibility of the last explanation. We find that the regolith reservoir of adsorbed N2 is inadequate by itself to buffer the atmospheric isotopic composition, but may play a role depending on the total regolith surface area available.

  11. First Demonstration on Direct Laser Fabrication of Lunar Regolith Parts

    NASA Technical Reports Server (NTRS)

    Balla, Vamsi Krishna; Roberson, Luke B.; OConnor, Gregory W. O.; Trigwell, Stephen; Bose, Susmita; Bandyopadhyay, Amit

    2010-01-01

    Establishment of a lunar or Martian outpost necessitates the development of methods to utilize in situ mineral resources for various construction and resource extraction applications. Fabrication technologies are critical for habitat structure development, as well as repair and replacement of tools and parts at the outpost. Herein we report the direct fabrication of lunar regolith simulant parts, in freeform environment, using lasers. We show that raw lunar regolith can be processed at laser energy levels as a low as 2.12 J mm-2 resulting in nanocrystalline and/or amorphous microstructures. Potential applications of laser based fabrication technologies to make useful regolith parts for various applications including load bearing composite structures, radiation shielding, and solar cell substrates is described.

  12. Inert gases in Sea of Fertility regolith

    NASA Technical Reports Server (NTRS)

    Vinogradov, A. P.; Zadorozhnyy, I. K.

    1974-01-01

    The content and isotopic composition were studied of inert gases -- He, Ne, Ar, Kr, and Xe -- in samples of lunar regolith returned by the Luna 16 automatic station. The samples were taken from depths of about 12 and 30 cm. The high concentrations of inert gases exceed by several orders their concentrations observed in ordinary stony meteorites. The gases in lunar regolith were a complex mixture of gases of different origins: Solar, cosmogenic, radiogenic, and so on. Solar wind gases predominated, distributed in the thin surficial layer of the regolith grains. The concentrations of these gases in the surficial layer is several cubic centimeters per gram. The isotopic composition of the inert gases of solar origin approaches their composition measured in gas-rich meteorites.

  13. Contact Electrification of Regolith Particles and Chloride Electrolysis: Synthesis of Perchlorates on Mars.

    PubMed

    Tennakone, K

    2016-10-01

    Contact electrification of chloride-impregnated martian regolith particles due to eolian agitation and moisture condensation on coalesced oppositely charged grains may lead to spontaneous electrolysis that generates hypochlorite, chlorite, chlorate, and perchlorate with a concomitant reduction of water to hydrogen. This process is not curtailed even if moisture condenses as ice because chloride ionizes on the surface of ice. Limitations dictated by potentials needed for electrolysis and breakdown electric fields enable estimation of the required regolith grain size. The estimated dimension turns out to be of the same order of magnitude as the expected median size of martian regolith, and a simple calculation yields the optimum rate of perchlorate production. Key Words: Mars oxidants-Perchlorate-Dust electrification-Electrolysis. Astrobiology 16, 811-816.

  14. Chemical characteristics and origin of H chondrite regolith breccias

    NASA Technical Reports Server (NTRS)

    Lipschutz, M. E.; Biswas, S.; Mcsween, H. Y., Jr.

    1983-01-01

    Petrologic data and contents of Ag, Bi, Cd, Co, Cs, Ga, In, Rb, Se, Te, Tl and Zn-trace elements spanning the volatility/mobility range-in light and dark portions of H chondrite regolith breccias and L chondrite fragmental breccias are reported. The chemical/petrologic characteristics of H chondrite regolith breccias differ from those of nonbrecciated chondrites or fragmental breccias. Petrologic characteristics and at least some trace element contents of H chondrite regolith breccias reflect primary processes; contents of the most volatile/mobile elements may reflect either primary or secondary processing, possibly within layered H chondrite parent object(s). Chemical/petrologic differences existed in different regions of the parent(s). Regoligh formation and gardening and meteoroid compaction were not so severe as to alter compositions markedly.

  15. Statistical models of lunar rocks and regolith

    NASA Technical Reports Server (NTRS)

    Marcus, A. H.

    1973-01-01

    The mathematical, statistical, and computational approaches used in the investigation of the interrelationship of lunar fragmental material, regolith, lunar rocks, and lunar craters are described. The first two phases of the work explored the sensitivity of the production model of fragmental material to mathematical assumptions, and then completed earlier studies on the survival of lunar surface rocks with respect to competing processes. The third phase combined earlier work into a detailed statistical analysis and probabilistic model of regolith formation by lithologically distinct layers, interpreted as modified crater ejecta blankets. The fourth phase of the work dealt with problems encountered in combining the results of the entire project into a comprehensive, multipurpose computer simulation model for the craters and regolith. Highlights of each phase of research are given.

  16. Thickness and character of regolith on mountain slopes in the vicinity of Mountain Lake, Virginia, as indicated by seismic refraction, and implications for hillslope evolution

    NASA Astrophysics Data System (ADS)

    Mills, Hugh H.

    1990-06-01

    Seismic refraction was used to determine the variation in thickness and seismic velocities of regolith on boulder-mantled mountain flanks underlain by shale in the Valley and Ridge province near Mountain Lake, southwestern Virginia. Emphasis was on cross-slope variations, particularly the difference between dells (hollows) and noses. Four types of material were distinguished on the basis of seismic velocity. Soil material within 1-2 m of the ground surface affected by pedogenesis had a velocity generally less than 400 m/s. Unconsolidated bouldery colluvium, up to 6 m thick, had a velocity of about 400-800 m/s. Old, weathered and consolidated colluvium had a velocity of 800-2000 m/s. Bedrock residuum and highly weathered bedrock showed similar velocities, however, so that all material in this range was collectively termed "weathered regolith." Its thickness exceeded 30 m in places. Relatively unweathered bedrock showed velocities of at least 2000 m/s. On average, seismic profiles showed regolith thicknesses in excess of 10 m, the greater part being residuum or weathered bedrock. This finding contrasts with one study near the glacial border in Pennsylvania, which showed that colluvium generally directly overlies bedrock. This difference may reflect less-intense Pleistocene periglacial erosion in Virginia than in Pennsylvania. Topography generally was not a good predictor of regolith thickness. Hollows showed greater thicknesses of ypung colluvium than did noses, but dells and noses showed little difference in total regolith thickness. Both dells and noses showed great variation in regolith thickness. The largest systematic difference was found between dell floors (or parts thereof) that seemed to be undergoing long-term downcutting and those that appeared to be relict features no longer associated with active drainageways. The former were underlain by a mean of 5.5 m of weathered regolith, whereas the latter were underlain by a mean of 14.0 m, indicative of a greater depth of weathering and therefore a greater antiquity. On three noses, closely spaced seismic profiles were used to demonstrate asymmetric distribution of regolith thickness in a direction transverse to nose axes. Findings are compatible with the concept that noses and dells on the boulder-mantled mountain slopes undergo topographic inversion during long-term retreat of the mountain front.

  17. Archway for Radiation and Micrometeorite Occurrence Resistance

    NASA Technical Reports Server (NTRS)

    Giersch, Louis R.

    2012-01-01

    The environmental conditions of the Moon require mitigation if a long-term human presence is to be achieved for extended periods of time. Radiation, micrometeoroid impacts, high-velocity debris, and thermal cycling represent threats to crew, equipment, and facilities. For decades, local regolith has been suggested as a candidate material to use in the construction of protective barriers. A thickness of roughly 3m is sufficient protection from both direct and secondary radiation from cosmic rays and solar protons; this thickness is sufficient to reduce radiation exposure even during solar flares. NASA has previously identified a need for innovations that will support lunar habitats using lightweight structures because the reduction of structural mass translates directly into additional up and down mass capability that would facilitate additional logistics capacity and increased science return for all mission phases. The development of non-pressurized primary structures that have synergy with the development of pressurized structures is also of interest. The use of indigenous or in situ materials is also a well-known and active area of research that could drastically improve the practicality of human exploration beyond low-Earth orbit. The Archway for Radiation and Micrometeorite Occurrence Resistance (ARMOR) concept is a new, multifunctional structure that acts as radiation shielding and micrometeorite impact shielding for long-duration lunar surface protection of humans and equipment. ARMOR uses a combination of native regolith and a deployed membrane jacket to yield a multifunctional structure. ARMOR is a robust and modular system that can be autonomously assembled on-site prior to the first human surface arrival. The system provides protection by holding a sufficiently thick (3 m) archshaped shell of local regolith around a central cavity. The regolith is held in shape by an arch-shaped jacket made of strong but deployable material. No regolith processing is required. During the regolith filling process, an inflatable structure under the arch supports the mass of the regolith, but once regolith filling is complete the catenary arch formed by the regolith and the jacket becomes self-supporting and the inflatable can be deflated and removed. When complete, habitat modules and equipment can be moved into the protected cavity under the arch. ARMOR is a nearterm system that would provide a reliable and robust lightweight structure technology to support large lunar habitats, drastically lower launch mass, and improve efficient volume use, reducing launch costs.

  18. Study of Electro-Cyclonic Filtration and Pneumatic Transfer of Lunar Regolith Simulants under 1/6-g and 1-g Gravity Conditions

    NASA Technical Reports Server (NTRS)

    Mantovani, James G.; Townsend, Ivan I.; Mueller, Robert P.

    2009-01-01

    NASA has built a prototype oxygen production plant to process the lunar regolith using the hydrogen reduction chemical process. This plant is known as "ROxygen - making oxygen from moon rocks". The ROxygen regolith transfer team has identified the flow and transfer characteristics of lunar regolith simulant to be a concern for lunar oxygen production efforts. It is important to ISRU lunar exploration efforts to develop hardware designs that can demonstrate the ability to flow and transfer a given mass of regolith simulant to a desired vertical height under lunar gravity conditions in order to introduce it into a reactor. We will present results obtained under both 1/6-g and 1-g gravity conditions for a system that can pneumatically convey 16.5 kg of lunar regolith simulant (NU-LHT-2M, Mauna Kea Tephra, and JSC-1A) from a flat-bottom supply hopper to a simulated ISRU reactor (dual-chambered receiving hopper) where the granular material is separated from the convey gas (air) using a series of cyclone separators, one of which is an electrically enhanced cyclone separator (electrocyclone). The results of our study include (1) the mass flow rate as a function of input air pressure for lunar regolith simulants that are conveyed pneumatically as a dusty gas in a vertical direction against gravity under lunar gravity conditions (for NU-LHT-2M and Mauna Kea Tephra), and under earth gravity conditions (for NU-LHT-2M, Mauna Kea Tephra and JSC-1A), and (2) the efficiency of the cyclone/electrocyclone filtration system in separating the convey gas (air) from the granular particulates as a function of particle size.

  19. Mars Gardens in the University - Red Thumbs: Growing Vegetables in Martian regolith simulant.

    NASA Astrophysics Data System (ADS)

    Guinan, Edward Francis

    2018-01-01

    Over the next few decades NASA and private enterprise missions plan to send manned missions to Mars with the ultimate aim to establish a permanent human presence on this planet. For a self-sustaining colony on Mars it will be necessary to provide food by growing plants in sheltered greenhouses on the Martian surface. As part of an undergraduate student project in Astrobiology at Villanova University, experiments are being carried out, testing how various plants grow in Martian regolith. A wide sample of plants are being grown and tested in Mars regolith simulant commercially available from The Martian Garden (TheMartian Garden.com). This Mars regolith simulant is based on Mojave Mars Simulant (MMS) developed by NASA and JPL for the Mars Phoenix mission. The MMS is based on the Mojave Saddleback basalt similar that used by JPL/NASA. Additional reagents were added to this iron rich basalt to bring the chemical content close to actual Mars regolith. The MMS used is an approximately 90% similar to regolith found on the surface of Mars - excluding poisonous perchlorates commonly found on actual Mars surface.The students have selected various vegetables and herbs to grow and test. These include carrots, spinach, dandelions, kale, soy beans, peas, onions, garlic and of course potatoes and sweet potatoes. Plants were tested in various growing conditions, using different fertilizers, and varying light conditions and compared with identical “control plants” grown in Earth soil / humus. The results of the project will be discussed from an education view point as well as from usefulness for fundamental research.We thank The Martian Garden for providing Martian regolith simulant at education discounted prices.

  20. Loss of oxygen, silicon, sulfur, and potassium from the lunar regolith

    NASA Technical Reports Server (NTRS)

    Clayton, R. N.; Mayeda, T. K.; Hurd, J. M.

    1974-01-01

    The processes of formation and maturation of lunar soils lead to enrichments in the heavy stable isotopes of oxygen, silicon, sulfur, and potassium. The isotopic enrichment implies substantial losses of these elements from the moon. Vaporization by micrometeorite impact and by ion sputtering have removed at least 1% of the mass of the regolith. The losses of sulfur and potassium amount to at least 20-30% of their original abundance in the regolith.

  1. Lunar regolith stratigraphy analysis based on the simulation of lunar penetrating radar signals

    NASA Astrophysics Data System (ADS)

    Lai, Jialong; Xu, Yi; Zhang, Xiaoping; Tang, Zesheng

    2017-11-01

    The thickness of lunar regolith is an important index of evaluating the quantity of lunar resources such as 3He and relative geologic ages. Lunar penetrating radar (LPR) experiment of Chang'E-3 mission provided an opportunity of in situ lunar subsurface structure measurement in the northern mare imbrium area. However, prior work on analyzing LPR data obtained quite different conclusions of lunar regolith structure mainly because of the missing of clear interface reflectors in radar image. In this paper, we utilized finite-difference time-domain (FDTD) method and three models of regolith structures with different rock density, number of layers, shapes of interfaces, and etc. to simulate the LPR signals for the interpretation of radar image. The simulation results demonstrate that the scattering signals caused by numerous buried rocks in the regolith can mask the horizontal reflectors, and the die-out of radar echo does not indicate the bottom of lunar regolith layer and data processing such as migration method could recover some of the subsurface information but also result in fake signals. Based on analysis of simulation results, we conclude that LPR results uncover the subsurface layered structure containing the rework zone with multiple ejecta blankets of small crater, the ejecta blanket of Chang'E-3 crater, and the transition zone and estimate the thickness of the detected layer is about 3.25 m.

  2. Space Environmental Erosion of Polar Icy Regolith

    NASA Technical Reports Server (NTRS)

    Farrell, William M.; Killen, R. M.; Vondrak, R. R.; Hurley, D. M.; Stubbs, T. J.; Delory, G. T.; Halekas, J. S.; Zimmerman, M. I.

    2011-01-01

    While regions at the floors of permanently shadowed polar craters are isolated from direct sunlight, these regions are still exposed to the harsh space environment, including the interplanetary Lyman-a background, meteoric impacts, and obstacle-affected solar wind. We demonstrate that each of these processes can act to erode the polar icy regolith located at or near the surface along the crater floor. The Lyman-a background can remove/erode the icy-regolith via photon stimulated desorption [1], meteoric impacts can vaporize the regolith [2], and redirected solar wind ions can sputter the ice-regolith mix [3]. As an example we shall examine in detail the inflow of solar wind ions and electrons into polar craters, One might expect such ions to flow horizontally over the crater top (see Figure). However, we find that plasma ambipolar processes act to deflect passing ions into the craters [3]. We examine this plasma process and determine the ion flux as a function of position across a notional crater floor. We demonstrate that inflowing solar wind ions can indeed create sputtering along the crater floor, effectively eroding the surface. Erosion time scales rrom sputtering will be presented. We shall also consider the effect of impact vaporization on buried icy-regolith regions. There will also be a discussion of solar wind electrons that enter into the PSR, demonstrating that these also have the ability rree surface-bound atoms via electron stimulated desorption processes [l].

  3. Assessing the elements mobility through the regolith and their potential as tracers for hydrological processes

    NASA Astrophysics Data System (ADS)

    Moragues-Quiroga, Cristina; Hissler, Christophe; Chabaux, François; Legout, Arnaud; Stille, Peter

    2017-04-01

    Regoliths encompass different materials from the fresh bedrock to the top of the organic horizons. The regolith is a major component of the critical zone where fluxes of water, energy, solutes and matter occur. Therefore, its bio-physico-chemical properties drastically impact the water that percolates and/or stores in its different parts (organic and mineral soil horizons, and weathered and fractured bedrock). In order to better understand the critical zone functioning, we propose to assess the interaction between chemical elements from the regolith matrix and water during drainage infiltration. For this, we focus firstly on the potential mobility of different groups of major and trace elements according to a leaching experiment made on 10 different layers of a 7.5 m depth slate regolith, which covers a large part of the Rhenish Massif. Secondly, we carried out Sr-Nd-Pb-U-Th isotope analyses for 5 of these samples in both the untreated and leached samples. Given the specific chemical and mineralogical composition of each sampled material, our approach enables to trace the origin of major and trace elements and eventually assess their mobility. The results deliver valuable information on exchange processes at the water-mineral interface in the different zones of the regolith, which could improve the selection of tracers for the study of hydrological processes.

  4. Geochemical comparison of impact glasses from lunar meteorites ALHA81005 and MAC88105 and Apollo 16 regolith 64001

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Delano, J.W.

    1991-11-01

    Most glasses that occur in lunar highland regolith are quenched droplets of impact melt. The chemical compositions of these glasses are equivalent, in the absence of volatile losses, to the original target materials. The compositional range of impact glasses in a regolith reflects the chemical diversity that existed throughout the region up to the time of system closure (e.g., breccia formation). Since these glasses are a product of widespread and random sampling, both in terms of space and time, they can be used for geochemical exploration of the Moon. The major-element compositions of impact glasses occurring in three samples ofmore » lunar feldspathic regolith (ALHA81005; MAC88105; Apollo 16 64001) have been determined by electron microprobe. The glass populations among these three unrelated samples are compositionally distinct. While most of the impact glasses within each of these three samples are compositionally similar to the regolith in which they are found, up to 40% of the impact glasses are different. Some of the compositionally exotic glasses were ballistically transported from other areas of the Moon and thereby provide information about the compositional range of regoliths that exist elsewhere. Since the geological setting of the Apollo 16 region is well known compared to the source areas of the lunar meteorites, the Apollo 16 glasses provide a ground truth for interpretations.« less

  5. Evolution of Regolith Feed Systems for Lunar ISRU 02 Production Plants

    NASA Technical Reports Server (NTRS)

    Mueller, Robert P.; Townsend, Ivan I., III; Mantovani, James G.; Metzger, Philip T.

    2010-01-01

    The In-Situ Resource Utilization (ISRU) project of the NASA Constellation Program, Exploration Technology Development Program (ETDP) has been engaged in the design and testing of various Lunar ISRU O2 production plant prototypes that can extract chemically bound oxygen from the minerals in the lunar regolith. This work demands that lunar regolith (or simulants) shall be introduced into the O2 production plant from a holding bin or hopper and subsequently expelled from the ISRU O2 production plant for disposal. This sub-system is called the Regolith Feed System (RFS) which exists in a variety of configurations depending on the O2 production plant oxygen being used (e.g. Hydrogen Reduction, Carbothermal, Molten Oxide Electrolysis). Each configuration may use a different technology and in addition it is desirable to have heat recuperation from the spent hot regolith as an integral part of the RFS. This paper addresses the various RFS and heat recuperation technologies and system configurations that have been developed under the NASA ISRU project since 2007. In addition current design solutions and lessons learned from reduced gravity flight testing will be discussed.

  6. Photomosaics of the cathodoluminescence of 60 sections of meteorites and lunar samples

    USGS Publications Warehouse

    Akridge, D.G.; Akridge, J.M.C.; Batchelor, J.D.; Benoit, P.H.; Brewer, J.; DeHart, J.M.; Keck, B.D.; Jie, L.; Meier, A.; Penrose, M.; Schneider, D.M.; Sears, D.W.G.; Symes, S.J.K.; Yanhong, Z.

    2004-01-01

    Cathodoluminescence (CL) petrography provides a means of observing petrographic and compositional properties of geological samples not readily observable by other techniques. We report the low-magnification CL images of 60 sections of extraterrestrial materials. The images we report include ordinary chondrites (including type 3 ordinary chondrites and gas-rich regolith breccias), enstatite chondrites, CO chondrites and a CM chondrite, eucrites and a howardite, lunar highland regolith breccias, and lunar soils. The CL images show how primitive materials respond to parent body metamorphism, how the metamorphic history of EL chondrites differs from that of EH chondrites, how dark matrix and light clasts of regolith breccias relate to each other, how metamorphism affects eucrites, the texture of lunar regolith breccias and the distribution of crystallized lunar spherules ("lunar chondrules"), and how regolith working affects the mineral properties of lunar soils. More particularly, we argue that such images are a rich source of new information on the nature and history of these materials and that our efforts to date are a small fraction of what can be done. Copyright 2004 by the American Geophysical Union.

  7. Conceptual design of equipment to excavate and transport regolith from the lunar maria

    NASA Technical Reports Server (NTRS)

    Detwiler, Mark; Foong, Chee Seng; Stocklin, Catherine

    1990-01-01

    NASA hopes to have a manned lunar outpost completed by 2005. In order to establish the base, regolith must be excavated from the lunar surface. Regolith will be used as a source for life-supporting elements and as radiation shielding for the lunar outpost. The design team from the University of Texas at Austin designed excavation and transportation equipment for initial operations of the lunar base. The design team also characterized the elements to be found in the regolith and determined the power required to excavate regolith. The characterization of the soil was based on a literature review of lunar geography. Power requirements for excavation were developed by adapting terrestrial equations for excavation power requirements and adapting them to lunar soil conditions. The design of the excavation and transportation equipment was broken into three functions: loosing, collecting, and transporting. A scarifier was selected to loosen, a bucket was selected to collect, and a load-haul system was selected to transport. The functions are powered by a modular fuel cell powered vehicle that provides power for motion of the equipment.

  8. Analysis of Water Extraction From Lunar Regolith

    NASA Technical Reports Server (NTRS)

    Hegde, U.; Balasubramaniam, R.; Gokoglu, S.

    2012-01-01

    Distribution of water concentration on the Moon is currently an area of active research. Recent studies suggest the presence of ice particles, and perhaps even ice blocks and ice-cemented regolith on the Moon. Thermal extraction of the in-situ water is an attractive means of sa tisfying water requirements for a lunar mission. In this paper, a model is presented to analyze the processes occurring during the heat-up of icy regolith and extraction of the evolved water vapor. The wet regolith is assumed to be present in an initially evacuated and sealed cell which is subsequently heated. The first step of the analysis invol ves calculating the gradual increase of vapor pressure in the closed cell as the temperature is raised. Then, in the second step, the cell is evacuated to low pressure (e.g., vacuum), allowing the water vapor to leave the cell and be captured. The parameters affecting water vap or pressure build-up and evacuation for the purpose of extracting water from lunar regolith are discussed in the paper. Some comparisons wi th available experimental measurements are also made.

  9. "Solar-Wind-Rich" Howardite: True Regolith vs. CM-Implanted Components

    NASA Technical Reports Server (NTRS)

    Cartwright, Julia A.; Mittlefehldt, D. W.; Herrin, J. S.; Hermann, S.; Ott, U.

    2011-01-01

    Howardite, eucrite and diogenite meteorites (collectively HED) likely originate from asteroid 4-Vesta [1], one of two asteroids targeted by NASA s Dawn mission. Many howardites (polymict breccias of E and D material) contain "regolithic" features, including impact-melt clasts, fragmental breccia clasts, and carbonaceous chondrite fragments. True regolithic nature can be determined through noble gas analysis, as Solar Wind (SW) is implanted into the upper-most surfaces of solar system bodies. Whilst previous work [2] suggested that high siderophile element contents (e.g. Ni of 300-1200 g/g) were regolith indicators, we found no obvious correlation between SW and these indicators in our initial howardite noble gas analyses [3]. We observed CM-like fragments in a number of our howardites, whose textures suggest late addition to the breccia assemblage [4]. As typical CMs contain mixtures of SW (in matrix) and planetary (in clasts) components [5], we investigate the dominance of such components in SW-rich howardites. This will help deter-mine the extent of implanted SW in HED grains vs. SW and planetary gases from CM fragments, and allow better understanding of regolith processes

  10. Nature of the H chondrite parent body regolith - Evidence from the Dimmitt breccia

    NASA Technical Reports Server (NTRS)

    Rubin, A. E.; Scott, E. R. D.; Taylor, G. J.; Keil, K.; Allen, J. S. B.; Mayeda, T. K.; Clayton, R. N.; Bogard, D. D.

    1983-01-01

    Meteorite regolith breccias are clastic rocks which formed by lithification of fragmental regolith material that once resided at the surface of a meteorite parent body. A study is reported of the matrix and 21 clasts of various sizes (0.2-24 mm) in the Dimmitt H chondrite regolith breccia using petrographic and electron microprobe techniques. In addition, oxygen isotope studies of three clasts and instrumental neutron activation analysis (INAA) and Ar-39/Ar-40 age dating of one clast are reported. The Dimmitt meteorite was found about 1942 near Dimmitt, Texas. Attention is given to analytical procedures, the clastic matrix, equilibrated clasts, poikilitic melt-rock clast, clasts of different chondrite groups, graphite-magnetite aggregates, the origin of exotic clasts, and the complexity of parent body surfaces processes.

  11. Construction with Regolith

    NASA Technical Reports Server (NTRS)

    Mueller, Robert P.

    2017-01-01

    CLASS node of SSERVI at FSI, The Technology and Future of In-Situ Resource Utilization (ISRU): ACapstone Graduate Seminar Orlando, FL. This seminar will discuss the use of regolith and robotics in extra terrestrialconstruction.

  12. Figure of Merit Characteristics Compared to Engineering Parameters

    NASA Technical Reports Server (NTRS)

    Rickman, Doug L.; Schrader, Christian M.

    2008-01-01

    Current NASA lunar architecture calls for permanent human habitation of the moon by the year 2020. Due to the expense of delivering materials into orbit, technologies are being developed to use lunar regolith for building and as a material resource for fabrication, oxygen production, and other needs. Additionally, constant exposure to the finest size fraction of lunar regolith may present hazards to human health. Towards developing these technologies and mitigating hazards, lunar regolith simulants are becoming an increasingly important part of the development paradigm.

  13. Beneficiation of lunar rocks and regolith - Concepts and difficulties

    NASA Technical Reports Server (NTRS)

    Taylor, Lawrence A.; Mckay, David S.

    1992-01-01

    Some of the inherent differences between lunar rocks and the finer portion of the regolith, the soil, are discussed. A brief outline of the formation of lunar soil is presented. Beneficiation of rocks vs regolith for the production of an ilmenite feedstock is addressed in particular, but the concepts and principles considered are applicable to other situations as well. The overall systems design must take the range of available feedstocks into account. Decisions on design that will influence feedstock requirements must be made.

  14. Mars Simulant Development for In-Situ Resource Utilization (ISRU) Applications

    NASA Technical Reports Server (NTRS)

    Ming, Doug

    2016-01-01

    Current design reference missions for the Evolvable Mars Campaign (EMC) call for the use of in-situ resources to enable human missions to the surface of Mars. One potential resource is water extracted from the Martian regolith. Current Mars' soil analogs (JSC Mars-1) have 5-10 times more water than typical regolith on Mars. Therefore, there is a critical need to develop Mars simulants to be used in ISRU applications that mimic the chemical, mineralogical, and physical properties of the Martian regolith.

  15. Regolith-Derived Heat Shield for Planetary Body Entry and Descent System with In-Situ Fabrication

    NASA Technical Reports Server (NTRS)

    Hogue, Michael D.; Mueller, Robert P.; Sibille, Laurent; Hintze, Paul E.; Rasky, Daniel J.

    2012-01-01

    High-mass planetary surface access is one of NASA's Grand Challenges involving entry, descent, and landing (EDL). Heat shields fabricated in-situ can provide a thermal protection system for spacecraft that routinely enter a planetary atmosphere. Fabricating the heat shield from extraterrestrial regolith will avoid the costs of launching the heat shield mass from Earth. This project investigated three methods to fabricate heat shield using extraterrestrial regolith and performed preliminary work on mission architectures.

  16. 75 FR 65673 - Notice of Information Collection

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-26

    ... purpose of this survey is to assimilate lunar regolith stimulant requirements as well as Apollo sample.... III. Data Title: Lunar Regolith & Stimulant Users' Survey for the In Situ Resource Utilization Web...

  17. 75 FR 53349 - Notice of Information Collection

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-31

    ... purpose of this survey is to assimilate lunar regolith stimulant requirements as well as Apollo sample.... III. Data Title: Lunar Regolith & Stimulant Users' Survey for the In Situ Resource Utilization Web...

  18. Lunar regolith and structure mechanics

    NASA Technical Reports Server (NTRS)

    Barnes, Frank; Ko, Hon-Yim; Sture, Stein; Carter, Tyrone R.; Evenson, Kraig A.; Nathan, Mark P.; Perkins, Steve W.

    1991-01-01

    The topics are presented in viewgraph form and include the following: modeling of regolith-structure interaction in extraterrestrial constructed facilities; densification of lunar soil simulant; and vibration assisted penetration of lunar soil simulant.

  19. PlanetVac: Sample Return with a Puff of Gas

    NASA Astrophysics Data System (ADS)

    Zacny, K.; Mueller, R.; Betts, B. H.

    2014-12-01

    PlanetVac is a regolith sample acquisition mission concept that uses compressed gas to blow material from the surface up a pneumatic tube and directly into a sample return container. The PlanetVac sampling device is built into the lander legs to eliminate cost and complexity associated with robotic arms and scoops. The pneumatic system can effectively capture fine and coarse regolith, including small pebbles. It is well suited for landed missions to Mars, asteroids, or the Moon. Because of the low pressures on all those bodies, the technique is extremely efficient. If losses are kept to minimum, 1 gram of compressed gas could efficiently lift 6000 grams of soil. To demonstrate this approach, the PlanetVac lander with four legs and two sampling tubes has been designed, integrated, and tested. Vacuum chamber testing was performed using two well-known planetary regolith simulants: Mars Mojave Simulant (MMS) and lunar regolith simulant JSC-1A. One of the two sampling systems was connected to a mockup of an earth return rocket while the second sampling system was connected to a lander deck mounted instrument (clear box for easy viewing). The tests included a drop from a height of approximately 50 cm onto the bed of regolith, deployment of sampling tubes into the regolith, pneumatic acquisition of sample into an instrument (sample container) and the rocket, and the launch of the rocket. The demonstration has been successful and can be viewed here: https://www.youtube.com/watch?v=DjJXvtQk6no. In most of the tests, 20 grams or more of sample was delivered to the 'instrument' and approximately 5 grams of regolith was delivered into a sampling chamber within the rocket. The gas lifting efficiency was calculated to be approximately 1000:1; that is 1 gram of gas lofted 1000 grams of regolith. Efficiencies in lower gravity environments are expected to be much higher. This successful, simple and lightweight sample capture demonstration paves the way to using such sampling system on either NASA or commercial landers to the Moon, Asteroids, comets, or Mars.

  20. Understanding the hydrologic and geochemical control of regolith formation on shale in a hilly landscape

    NASA Astrophysics Data System (ADS)

    Xiao, D.; Brantley, S.; Li, L.

    2017-12-01

    Chemical weathering transforms rock to soil and determine soil texture, bedrock depth, and soil hydrological properties. At the Shale Hills watershed in central Pennsylvania, field evidence indicated that the regolith depth, hydrologic processes, and chemical depletion are different at the two aspects. Current regolith formation models considering reactive transport processes have a limitation in coupling complex and evolving hydrodynamic conditions. We hypothesize that deeper regolith forms when more water flushes dissolved mass out of the system. The hypothesis is tested by developing a two-dimensional regolith formation model at the hillslope scale using measured mineral composition and hydrologic properties at Shale Hills using CrunchFlow. A 2-D hillslope domain was setup to simulate hydrogeochemical processes at north and south aspects and to understand the evolution of hydrodynamics, rock properties, and extent of chemical reactions. The bedrock has the primary minerals of quartz, illite, chlorite, calcite, and pyrite; goethite and kaolinite precipitated as secondary minerals. The permeability, mass transfer, and groundwater table depth were constrained by field measurement. We implemented different recharge rates on north and south aspects based on the annually averaged fluxes from a current reanalysis using a hydrologic model. The simulation started from a homogeneous bedrock composition at 10,000 years ago. After 10,000 years' weathering, the south facing aspect with small recharge rate has a shallower soil and regolith. The simulation output indicates the formation of a shallow and a deep groundwater, based on the formation of lateral flow that connects to the stream. One is at the interface between high permeability soil zone and low permeability regolith zone, forming a relatively high-velocity perched groundwater layer. The remnant water infiltrates into the deeper low permeability zone and forms the regional groundwater layer. Because of high permeability in perched layer on north facing aspect, the remnant water in regional groundwater layer leads to shallower water table depth on north facing aspect. The model will be used to understand the role fractures, climate, and mineral compositions in affecting regolith formation.

  1. Sulfate deposition in subsurface regolith in Gusev crater, Mars

    USGS Publications Warehouse

    Wang, A.; Haskin, L.A.; Squyres, S. W.; Jolliff, B.L.; Crumpler, L.; Gellert, Ralf; Schroder, C.; Herkenhoff, K.; Hurowitz, J.; Tosca, N.J.; Farrand, W. H.; Anderson, R.; Knudson, A.T.

    2006-01-01

    Excavating into the shallow Martian subsurface has the potential to expose stratigraphic layers and mature regolith, which may hold a record of more ancient aqueous interactions than those expected under current Martian surface conditions. During the Spirit rover's exploration of Gusev crater, rover wheels were used to dig three trenches into the subsurface regolith down to 6-11 cm depth: Road Cut, the Big Hole, and The Boroughs. A high oxidation state of Fe and high concentrations of Mg, S, Cl, and Br were found in the subsurface regolith within the two trenches on the plains, between the Bonneville crater and the foot of Columbia Hills. Data analyses on the basis of geochemistry and mineralogy observations suggest the deposition of sulfate minerals within the subsurface regolith, mainly Mg-sulfates accompanied by minor Ca-sulfates and perhaps Fe-sulfates. An increase of Fe2O3, an excess of SiO2, and a minor decrease in the olivine proportion relative to surface materials are also inferred. Three hypotheses are proposed to explain the geochemical trends observed in trenches: (1) multiple episodes of acidic fluid infiltration, accompanied by in situ interaction with igneous minerals and salt deposition; (2) an open hydrologic system characterized by ion transportation in the fluid, subsequent evaporation of the fluid, and salt deposition; and (3) emplacement and mixing of impact ejecta of variable composition. While all three may have plausibly contributed to the current state of the subsurface regolith, the geochemical data are most consistent with ion transportation by fluids and salt deposition as a result of open-system hydrologic behavior. Although sulfates make up >20 wt.% of the regolith in the wall of The Boroughs trench, a higher hydrated sulfate than kieserite within The Boroughs or a greater abundance of sulfates elsewhere than is seen in The Boroughs wall regolith would be needed to hold the structural water indicated by the water-equivalent hydrogen concentration observed by the Gamma-Ray Spectrometer on Odyssey in the Gusev region. Copyright 2006 by the American Geophysical Union.

  2. A Combined XRD/XRF Instrument for Lunar Resource Assessment

    NASA Technical Reports Server (NTRS)

    Vaniman, D. T.; Bish, D. L.; Chipera, S. J.; Blacic, J. D.

    1992-01-01

    Robotic surface missions to the Moon should be capable of measuring mineral as well as chemical abundances in regolith samples. Although much is already known about the lunar regolith, our data are far from comprehensive. Most of the regolith samples returned to Earth for analysis had lost the upper surface, or it was intermixed with deeper regolith. This upper surface is the part of the regolith most recently exposed to the solar wind; as such it will be important to resource assessment. In addition, it may be far easier to mine and process the uppermost few centimeters of regolith over a broad area than to engage in deep excavation of a smaller area. The most direct means of analyzing the regolith surface will be by studies in situ. In addition, the analysis of the impact-origin regolith surfaces, the Fe-rich glasses of mare pyroclastic deposits, are of resource interest, but are inadequately known; none of the extensive surface-exposed pyroclastic deposits of the Moon have been systematically sampled, although we know something about such deposits from the Apollo 17 site. Because of the potential importance of pyroclastic deposits, methods to quantify glass as well as mineral abundances will be important to resource evaluation. Combined x ray diffraction (XRD) and x ray fluorescence (XRF) analysis will address many resource characterization problems on the Moon. XRF methods are valuable for obtaining full major-element abundances with high precision. Such data, collected in parallel with quantitative mineralogy, permit unambiguous determination of both mineral and chemical abundances where concentrations are high enough to be of resource grade. Collection of both XRD and XRF data from a single sample provides simultaneous chemical and mineralogic information. These data can be used to correlate quantitative chemistry and mineralogy as a set of simultaneous linear equations, the solution of which can lead to full characterization of the sample. The use of Rietveld methods for XRD data analysis can provide a powerful tool for quantitative mineralogy and for obtaining crystallographic data on complex minerals.

  3. A new mechanism for the formation of regolith on asteroids

    NASA Astrophysics Data System (ADS)

    Delbo, Marco; Libourel, Guy; Wilkerson, Justin; Murdoch, Naomi; Michel, Patrick; Ramesh, Kt; Ganino, Clement; Verati, Chrystele; Marchi, Simone

    2014-11-01

    The soil of asteroids, like that of the Moon, and other rocky, airless bodies in the Solar System, is made of a layer of pebbles, sand, and dust called regolith.Previous works suggested that the regolith on asteroids is made from material ejected from impacts and re-accumulated on the surface and from surface rocks that are broken down by micrometeoroid impacts. However, this regolith formation process has problems to explain the regolith on km-sized and smaller asteroids: it is known that impact fragments can reach escape velocities and breaks free from the gravitational forces of these small asteroids, indicating the impact mechanism is not the dominant process for regolith creation. Other studies also reveal that there is too much regolith on small asteroids’ surfaces to have been deposited there solely by impacts over the millions of years of asteroids’ evolution.We proposed that another process is capable of gently breaking rocks at the surface of asteroids: thermal fatigue by temperature cycling. As asteroids spin about their rotation axes, their surfaces go in and out of shadow resulting in large surface temperature variations. The rapid heating and cooling creates thermal expansion and contraction in the asteroid material, initiating cracking and propagating existing cracks. As the process is repeated over and over, the crack damage increases with time, leading eventually to rock fragmentation (and production of new regolith).To study this process, in the laboratory, we subjected meteorites, used as asteroid material analogs, to 37 days of thermal cycles similar to those occurring on asteroids. We measured cracks widening at an average rate of 0.5 mm/y. Some fragments were also produced, indicating meteorite fragmentation. To scale our results to asteroid lifetime, we incorporated our measurements into a fracture model and we deduced that thermal cycling is more efficient than micrometeorite bombardment at fragmenting rock over millions of years on asteroids (see Delbo et al. 2014. Nature 508, 233-236).This work was supported by the French Agence National de la Recherche (ANR) SHOCKS,

  4. Radiation Shielding of Lunar Regolith/Polyethylene Composites and Lunar Regolith/Water Mixtures

    NASA Technical Reports Server (NTRS)

    Johnson, Quincy F.; Gersey, Brad; Wilkins, Richard; Zhou, Jianren

    2011-01-01

    Space radiation is a complex mixed field of ionizing radiation that can pose hazardous risks to sophisticated electronics and humans. Mission planning for lunar exploration and long duration habitat construction will face tremendous challenges of shielding against various types of space radiation in an attempt to minimize the detrimental effects it may have on materials, electronics, and humans. In late 2009, the Lunar Crater Observation and Sensing Satellite (LCROSS) discovered that water content in lunar regolith found in certain areas on the moon can be up to 5.6 +/-2.8 weight percent (wt%) [A. Colaprete, et. al., Science, Vol. 330, 463 (2010). ]. In this work, shielding studies were performed utilizing ultra high molecular weight polyethylene (UHMWPE) and aluminum, both being standard space shielding materials, simulated lunar regolith/ polyethylene composites, and simulated lunar regolith mixed with UHMWPE particles and water. Based on the LCROSS findings, radiation shielding experiments were conducted to test for shielding efficiency of regolith/UHMWPE/water mixtures with various percentages of water to compare relative shielding characteristics of these materials. One set of radiation studies were performed using the proton synchrotron at the Loma Linda Medical University where high energy protons similar to those found on the surface of the moon can be generated. A similar experimental protocol was also used at a high energy spalation neutron source at Los Alamos Neutron Science Center (LANSCE). These experiments studied the shielding efficiency against secondary neutrons, another major component of space radiation field. In both the proton and neutron studies, shielding efficiency was determined by utilizing a tissue equivalent proportional counter (TEPC) behind various thicknesses of shielding composite panels or mixture materials. Preliminary results from these studies indicated that adding 2 wt% water to regolith particles could increase shielding of the regolith materials by about 6%. The findings may be utilized to extend the possibilities of potential candidate materials for lunar habitat structures, will potentially impact the design criteria of future human bases on the moon, and provide some guidelines for future space mission planning with respect to radiation exposure and risks posed on astronauts.

  5. Multiphysics Modeling for Dimensional Analysis of a Self-Heated Molten Regolith Electrolysis Reactor for Oxygen and Metals Production on the Moon and Mars

    NASA Technical Reports Server (NTRS)

    Dominguez, Jesus A.; Sibille, Laurent

    2010-01-01

    The technology of direct electrolysis of molten lunar regolith to produce oxygen and molten metal alloys has progressed greatly in the last few years. The development of long-lasting inert anodes and cathode designs as well as techniques for the removal of molten products from the reactor has been demonstrated. The containment of chemically aggressive oxide and metal melts is very difficult at the operating temperatures ca 1600 C. Containing the molten oxides in a regolith shell can solve this technical issue and can be achieved by designing a self-heating reactor in which the electrolytic currents generate enough Joule heat to create a molten bath. In a first phase, a thermal analysis model was built to study the formation of a melt of lunar basaltic regolith irradiated by a focused solar beam This mode of heating was selected because it relies on radiative heat transfer, which is the dominant mode of transfer of energy in melts at 1600 C. Knowing and setting the Gaussian-type heat flux from the concentrated solar beam and the phase and temperature dependent thermal properties, the model predicts the dimensions and temperature profile of the melt. A validation of the model is presented in this paper through the experimental formation of a spherical cap melt realized by others. The Orbitec/PSI experimental setup uses an 3.6-cm diameter concentrated solar beam to create a hemispheric melt in a bed of lunar regolith simulant contained in a large pot. Upon cooling, the dimensions of the vitrified melt are measured to validate the thermal model. In a second phase, the model is augmented by multiphysics components to compute the passage of electrical currents between electrodes inserted in the molten regolith. The current through the melt generates Joule heating due to the high resistivity of the medium and this energy is transferred into the melt by conduction, convection and primarily by radiation. The model faces challenges in two major areas, the change of phase as temperature increases, and the dominance of radiative heat flux as heat transfer mechanism within the melt the change of phase concerns the regolith itself which is present in states ranging from a fine grain regolith with low thermal conductivity and low density to a vitrified melt with much higher thermal conductivity, and higher density. As the regolith is heated, it starts to soften around 1300 C the melt iS very viscous and evolving gas bubbles out in thick, lava-like fashion. By 1600 C the regolith is completely melted and the viscosity is low The second challenge resides in the proper modeling of the radiative heat flux requiring the addition of the computing-demanding radiative-heat-transfer function to the general heat transfer equation. The model Includes temperature-dependent properties (density, thermal conductivity, heat capacity, and viscosity, and absorption coefficients) and solves the radiative heat flux equation assuming gray (fine grains) and semi-transparent (melt) media and using an absorption coefficient spectral found in the literature for terrestrial minerals similar in composition to those of lunar regolith simulant

  6. Xe-126 Excesses: Monoisotopic Anomalies in Regolith Samples?

    NASA Technical Reports Server (NTRS)

    Mathew, K. J.; Marti, K.; Levskii, L. K.

    2003-01-01

    We present new Xe isotopic signatures of Pesyanoe regolith samples which document excesses of 126Xe and we explore the possibility that it formed by low-energy reactions on transient Te-rich coatings.

  7. Lunar Regolith Figures of Merit

    NASA Technical Reports Server (NTRS)

    Rickman, Doug; Scjrader. Cjrostoam; Jpe (zer. Jams); Fourroux, Kathy

    2009-01-01

    This viewgraph presentation reviews the lunar regolith figures of merit. The contents include: 1) A quick review of Figures-of-Merit (FoM); 2) Software Implementation of FoM Algorithms; and 3) Demonstration of the Software.

  8. On the sputter alteration of regoliths of outer solar system bodies

    NASA Technical Reports Server (NTRS)

    Hapke, B.

    1986-01-01

    The present theoretical and experimental consideration of processes that are expected to occur when the porous regoliths on outer solar system bodies lacking atmospheres are subjected to energetic ion bombardment indicates that porosity reduces the effective sputtering yield of a soil by more than an order of magnitude. Between 90 and 97 percent of the sputtered atoms are trapped within the regolith and subjected to differential desorption fractionation, which emerges as the most important path for the alteration of chemical and optical properties in sputtered regoliths. Sputtered porous mixtures of water, ammonia and methane frosts suffer a loss of H, and surface reactions of C, N, and O that should yield complex hydrocarbons and carbohydrates; such reactions may have played a role in the formation of carbonaceous chondrites' matrix material prior to agglomeration.

  9. Seasonal carbon dioxide exchange between the regolith and atmosphere of Mars - Experimental and theoretical studies

    NASA Technical Reports Server (NTRS)

    Fanale, F. P.; Salvail, J. R.; Banerdt, W. B.; Saunders, R. S.; Johansen, L. A.

    1982-01-01

    CO2 penetration rate measurements have been made through basalt-clay soils under conditions simulating the penetration of the cap-induced seasonal CO2 pressure wave through the topmost regolith of Mars, and results suggest that existing theoretical models for the diffusion of a gas through a porous and highly adsorbing medium may be used to assess the importance of the Martian seasonal regolith-atmosphere CO2 exchange. The maximum effect of thermally driven exchange between the topmost seasonally (thermally) affected regolith and the atmosphere shows that, while this may be of greater importance than the isothermal exchange, the thermally driven exchange would be recognizable only if the pressure wave from CO2 exchanged at high latitudes did not propagate atmospherically faster than the rate at which the exchange itself occurred. This is an unreasonable assumption.

  10. Near-term lander experiments for growing plants on Mars: requirements for information on chemical and physical properties of Mars regolith.

    PubMed

    Schuerger, Andrew C; Ming, Douglas W; Newsom, Horton E; Ferl, Robert J; McKay, Christopher P

    2002-01-01

    In order to support humans for long-duration missions to Mars, bioregenerative Advanced Life Support (ALS) systems have been proposed that would use higher plants as the primary candidates for photosynthesis. Hydroponic technologies have been suggested as the primary method of plant production in ALS systems, but the use of Mars regolith as a plant growth medium may have several advantages over hydroponic systems. The advantages for using Mars regolith include the likely bioavailability of plant-essential ions, mechanical support for plants, and easy access of the material once on the surface. We propose that plant biology experiments must be included in near-term Mars lander missions in order to begin defining the optimum approach for growing plants on Mars. Second, we discuss a range of soil chemistry and soil physics tests that must be conducted prior to, or in concert with, a plant biology experiment in order to properly interpret the results of plant growth studies in Mars regolith. The recommended chemical tests include measurements on soil pH, electrical conductivity and soluble salts, redox potential, bioavailability of essential plant nutrients, and bioavailability of phytotoxic elements. In addition, a future plant growth experiment should include procedures for determining the buffering and leaching requirements of Mars regolith prior to planting. Soil physical tests useful for plant biology studies in Mars regolith include bulk density, particle size distribution, porosity, water retention, and hydraulic conductivity.

  11. The extraordinary radar echoes from Europa, Ganymede, and Callisto: A geological perspective

    USGS Publications Warehouse

    Ostro, S.J.; Shoemaker, E.M.

    1990-01-01

    This outline of plausible geologic explanations for the icy Galilean satellites' radar properties takes into consideration electromagnetic scattering models for the echoes, available empirical and theoretical information about regolith formation, and ice physics. The strange radar signatures arise because (1) ice is electrically different from silicates and/or (2) icy regoliths contain bulk-density (and hence refractive-index) structures absent within silicate regoliths. Ice's relatively high radar-frequency transparency compared with that of silicates permits longer photon path lengths, deeper radar sounding, and a greater number of scattering events. Consequently, scattering mechanisms that cannot contribute significantly to lunar echoes can dominate icy-satellite echoes. Possible phenomena unique to icy regoliths include (1) smoothing out of discontinuities between solid ejecta fragments and more porous surroundings under the action of thermal annealing to form refraction-scattering (RS) "lenses" and (2) formation of density enhancements in the shape of crater floors that result in RS and/or total internal reflection (TIR). In either case, high-order multiple scattering is more likely to be responsible for the echoes than low-order scattering. Radar/radio observations can constrain the order of the scattering and the scale of the structures responsible for the echoes but might not determine whether TIR or RS dominates the scattering. Multiwavelength investigations of the degree of correlation between radar properties and geologic terrain type should prove most useful, because inter- and intrasatellite variations in radar properties probably correspond to variations in ice purity, regolith thickness, and regolith thermal history and age. ?? 1990.

  12. CONCEPTUAL DESIGN OF A LUNAR REGOLITH CLUSTERED-REACTOR SYSTEM

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    John Darrell Bess

    2009-06-01

    It is proposed that a fast-fission, heatpipe-cooled, lunar-surface power reactor system be divided into subcritical units that could be launched safely without the incorporation of additional spectral shift absorbers or other complex means of control. The reactor subunits are to be emplaced directly into the lunar regolith utilizing the regolith not just for shielding but as the reflector material to increase the neutron economy of the system. While a single subunit cannot achieve criticality by itself, coordinated placement of additional subunits will provide a critical reactor system for lunar surface power generation. A lunar regolith clustered-reactor system promotes reliability, safety,more » and ease of manufacture and testing at the cost of a slight increase in launch mass per rated power level and an overall reduction in neutron economy when compared to a single-reactor system. Additional subunits may be launched with future missions to increase the cluster size and power according to desired lunar base power demand and lifetime. The results address the potential uncertainties associated with the lunar regolith material and emplacement of the subunit systems. Physical distance between subunits within the clustered emplacement exhibits the most significant feedback regarding changes in overall system reactivity. Narrow, deep holes will be the most effective in reducing axial neutron leakage from the core. The variation in iron concentration in the lunar regolith can directly influence the overall system reactivity although its effects are less than the more dominant factors of subunit emplacement.« less

  13. The Lunar Regolith as a Remote Sensing Target for the Lunar Reconnaissance Orbiter (LRO)

    NASA Technical Reports Server (NTRS)

    Mendell, Wendell W.

    2009-01-01

    Of the 6 instruments and one technology demonstration aboard the LRO, only CRaTER does not measure some kind of interaction of particles with the lunar regolith. LEND detects neutron fluence that contains information about the number density of protons in the upper regolith. To infer the presence of protons, the PI must assume a model that characterizes the surface as a collection of atoms. Thus, LEND does not sense the regolith as a structure. LROC, LOLA, and LAMP sense reflected photons whose wavelength is much shorter than the median particle size in the regolith. The photons interact with electrons, either in atomic shells or in chemical bonds. These interactions occur within a nanometer or so of the surface of a particle. Thus, the particles are macroscopic objects and models of the reflection process invoke ray-tracing optics. DIVINER senses photons that have been emitted by surface particles through thermal phonon processes. The wavelengths detected by the instrument are of the same order as the median particle size, and the photons contain information on particle dimensions as well as the molecular bonds in the constituent compounds. The Mini-RF synthetic aperture radar generates and detects photons of a few centimeters wavelength that interact with the regolith as a dielectric, the dielectric properties of the particulate component being described through effective medium theory. However, the interaction with rocks (macroscopic objects of interest to geologists) can be characterized using Fresnel or Mie models of electromagnetic properties.

  14. Near-term lander experiments for growing plants on Mars: requirements for information on chemical and physical properties of Mars regolith

    NASA Technical Reports Server (NTRS)

    Schuerger, Andrew C.; Ming, Douglas W.; Newsom, Horton E.; Ferl, Robert J.; McKay, Christopher P.

    2002-01-01

    In order to support humans for long-duration missions to Mars, bioregenerative Advanced Life Support (ALS) systems have been proposed that would use higher plants as the primary candidates for photosynthesis. Hydroponic technologies have been suggested as the primary method of plant production in ALS systems, but the use of Mars regolith as a plant growth medium may have several advantages over hydroponic systems. The advantages for using Mars regolith include the likely bioavailability of plant-essential ions, mechanical support for plants, and easy access of the material once on the surface. We propose that plant biology experiments must be included in near-term Mars lander missions in order to begin defining the optimum approach for growing plants on Mars. Second, we discuss a range of soil chemistry and soil physics tests that must be conducted prior to, or in concert with, a plant biology experiment in order to properly interpret the results of plant growth studies in Mars regolith. The recommended chemical tests include measurements on soil pH, electrical conductivity and soluble salts, redox potential, bioavailability of essential plant nutrients, and bioavailability of phytotoxic elements. In addition, a future plant growth experiment should include procedures for determining the buffering and leaching requirements of Mars regolith prior to planting. Soil physical tests useful for plant biology studies in Mars regolith include bulk density, particle size distribution, porosity, water retention, and hydraulic conductivity.

  15. Regolith Formation Rates and Evolution from the Diviner Lunar Radiometer

    NASA Astrophysics Data System (ADS)

    Hayne, P. O.; Ghent, R. R.; Bandfield, J. L.; Vasavada, A. R.; Williams, J. P.; Siegler, M. A.; Lucey, P. G.; Greenhagen, B. T.; Elder, C. M.; Paige, D. A.

    2015-12-01

    Fragmentation and overturn of lunar surface materials produces a layer of regolith, which increases in thickness through time. Experiments on the lunar surface during the Apollo era, combined with remote sensing, found that the upper 10's of cm of regolith exhibit a rapid increase in density and thermal conductivity with depth. This is interpreted to be the signature of impact gardening, which operates most rapidly in the uppermost layers. Gravity data from the GRAIL mission showed that impacts have also extensively fractured the deeper crust. The breakdown and mixing of crustal materials is therefore a central process to lunar evolution and must be understood in order to interpret compositional information from remote sensing and sample analysis. Recently, thermal infrared data from the Lunar Reconnaissance Orbiter (LRO) Diviner radiometer were used to provide the first remote observational constraints on the rate of ejecta breakdown around craters < 1 Ga (Ghent et al., 2014). Here, we use nighttime regolith temperatures derived from Diviner data to constrain regolith thermal inertia, thickness, and spatial variability. Applied to models, these new data help improve understanding of regolith formation on a variety of geologic units. We will also discuss several anomalous features that merit further investigation. Reference: Ghent, R. R., Hayne, P. O., Bandfield, J. L., Campbell, B. A., Allen, C. C., Carter, L. M., & Paige, D. A. (2014). Constraints on the recent rate of lunar ejecta breakdown and implications for crater ages. Geology, 42(12), 1059-1062.

  16. Identification of Martian Regolith Sulfur Components in Shergottites Using Sulfur K Xanes and Fe/S Ratios

    NASA Technical Reports Server (NTRS)

    Sutton, S. R.; Ross, D. K.; Rao, M. N.; Nyquist, L. E.

    2014-01-01

    Based on isotopic anomalies in Kr and Sm, Sr-isotopes, S-isotopes, XANES results on S-speciation, Fe/S ratios in sulfide immiscible melts [5], and major element correlations with S determined in impact glasses in EET79001 Lith A & Lith B and Tissint, we have provided very strong evidence for the occurrence of a Martian regolith component in some impact melt glasses in shergottites. Using REE measurements by LA-ICP-MS in shergottite impact glasses, Barrat and co-workers have recently reported conflicting conclusions about the occurrence of Martian regolith components: (a) Positive evidence was reported for a Tissint impact melt, but (b) Negative evidence for impact melt in EET79001 and another impact melt in Tissint. Here, we address some specific issues related to sulfur speciation and their relevance to identifying Martian regolith components in impact glasses in EET79001 and Tissint using sulfur K XANES and Fe/S ratios in sulfide immiscible melts. XANES and FE-SEM measurements in approx. 5 micron size individual sulfur blebs in EET79001 and Tissint glasses are carried out by us using sub-micron size beams, whereas Barrat and coworkers used approx. 90 micron size laser spots for LA- ICP-MS to determine REE abundances in bulk samples of the impact melt glasses. We contend that Martian regolith components in some shergottite impact glasses are present locally, and that studying impact melts in various shergottites can give evidence both for and against regolith components because of sample heterogeneity.

  17. The Shawmere anorthosite and OB-1 as lunar highland regolith simulants

    NASA Astrophysics Data System (ADS)

    Battler, Melissa M.; Spray, John G.

    2009-12-01

    Anorthosite constitutes a major component of the lunar crust and comprises an important, if not dominant, ingredient of the lunar regolith. Given the need for highland regolith simulants in preparation for lunar surface engineering activities, we have selected an appropriate terrestrial anorthosite and performed crushing trials to generate a particle size distribution comparable to Apollo 16 regolith sample 64 500. The root simulant is derived from a granoblastic facies of the Archean Shawmere Complex of the Kapuskasing Structural Zone of Ontario, Canada. The Shawmere exhibits minimal retrogression, is homogeneous and has an average plagioclase composition of An 78 (bytownite). Previous industrial interest in this calcic anorthosite has resulted in quarrying operations, which provide ease of extraction and access for potential large-scale simulant production. A derivative of the Shawmere involves the addition of olivine slag, crushed to yield a particle size distribution similar to that of the agglutinate and glass components of the Apollo sample. This simulant is referred to as OB-1. The Shawmere and OB-1 regolith simulants are lunar highland analogues, conceived to produce geotechnical properties of benefit to designing and testing drilling, excavation and construction equipment for future lunar surface operations.

  18. Non-equilibrium freezing of water-ice in sandy basaltic regoliths and implications for fluidized debris flows on Mars

    NASA Technical Reports Server (NTRS)

    Gooding, J. L.

    1987-01-01

    Many geomorphic features on Mars were attributed to Earth-analogous, cold-climate processes involving movement of water or ice lubricated debris. Clearly, knowledge of the behavior of water in regolith materials under Martian conditions is essential to understanding the postulated geomorphic processes. Experiments were performed with sand-sized samples of natural basaltic regoliths in order to further elucidate how water/regolith interactions depend upon grain size and mineralogy. The data reveal important contrasts with data for clay-mineral substrates and suggest that the microphysics of water/mineral interactions might affect Martian geomorphic processes in ways that are not fully appreciated. Sand and silt sized fractions of two soils from the summit of Mauna Kea were used as Mars-analogous regolith materials. Temperatures were measured for water/ice phase transitions as wet slurries of individual soil fractions which were cooled or heated at controlled rates under a carbon dioxide atmosphere. Freezing and melting of ice was studied as a function of water/soil mass ratio, soil particle size, and thermal-cycle rate. Comparison tests were done under the same conditions with U.S. Geological Survey standard rock powders.

  19. Martian regolith geochemistry and sampling techniques

    NASA Technical Reports Server (NTRS)

    Clark, B. C.

    1988-01-01

    Laboratory study of samples of the intermediate and fine-grained regolith, including duricrust peds, is a fundamental prerequisite for understanding the types of physical and chemical weathering processes on Mars. The extraordinary importance of such samples is their relevance to understanding past changes in climate, availability (and possible physical state) of water, eolian forces, the thermal and chemical influences of volcanic and impact processes, and the inventory and fates of Martian volatiles. Fortunately, this regolith material appears to be ubiquitous over the Martian surface, and should be available at many different landing sites. Viking data has been interpreted to indicate a smectite-rich regolith material, implying extensive weathering involving aqueous activity and geochemical alteration. An all-igneous source of the Martian fines has also been proposed. The X-ray fluorescence measurement data set can now be fully explained in terms of a simple two-component model. The first component is silicate, having strong geochemical similarities with Shergottites, but not other SNC meteorites. The second component is salt. Variations in these components could produce silicate and salt-rich beds, the latter being of high potential importance for microenvironments in which liquid water (brines) could exist. It therefore would be desirable to scan the surface of the regolith for such prospects.

  20. Martian regolith geochemistry and sampling techniques

    NASA Astrophysics Data System (ADS)

    Clark, B. C.

    Laboratory study of samples of the intermediate and fine-grained regolith, including duricrust peds, is a fundamental prerequisite for understanding the types of physical and chemical weathering processes on Mars. The extraordinary importance of such samples is their relevance to understanding past changes in climate, availability (and possible physical state) of water, eolian forces, the thermal and chemical influences of volcanic and impact processes, and the inventory and fates of Martian volatiles. Fortunately, this regolith material appears to be ubiquitous over the Martian surface, and should be available at many different landing sites. Viking data has been interpreted to indicate a smectite-rich regolith material, implying extensive weathering involving aqueous activity and geochemical alteration. An all-igneous source of the Martian fines has also been proposed. The X-ray fluorescence measurement data set can now be fully explained in terms of a simple two-component model. The first component is silicate, having strong geochemical similarities with Shergottites, but not other SNC meteorites. The second component is salt. Variations in these components could produce silicate and salt-rich beds, the latter being of high potential importance for microenvironments in which liquid water (brines) could exist. It therefore would be desirable to scan the surface of the regolith for such prospects.

  1. Lunar Proton Albedo Anomalies: Soil, Surveyors, and Statistics

    NASA Astrophysics Data System (ADS)

    Wilson, J. K.; Schwadron, N.; Spence, H. E.; Case, A. W.; Golightly, M. J.; Jordan, A.; Looper, M. D.; Petro, N. E.; Robinson, M. S.; Stubbs, T. J.; Zeitlin, C. J.; Blake, J. B.; Kasper, J. C.; Mazur, J. E.; Smith, S. S.; Townsend, L. W.

    2014-12-01

    Since the launch of LRO in 2009, the CRaTER instrument has been mapping albedo protons (~100 MeV) from the Moon. These protons are produced by nuclear spallation, a consequence of galactic cosmic ray (GCR) bombardment of the lunar regolith. Just as spalled neutrons and gamma rays reveal elemental abundances in the lunar regolith, albedo protons may be a complimentary method for mapping compositional variations. We presently find that the lunar maria have an average proton yield 0.9% ±0.3% higher than the average yield in the highlands; this is consistent with neutron data that is sensitive to the regolith's average atomic weight. We also see cases where two or more adjacent pixels (15° × 15°) have significantly anomalous yields above or below the mean. These include two high-yielding regions in the maria, and three low-yielding regions in the far-side highlands. Some of the regions could be artifacts of Poisson noise, but for completeness we consider possible effects from compositional anomalies in the lunar regolith, including pyroclastic flows, antipodes of fresh craters, and so-called "red spots". We also consider man-made landers and crash sites that may have brought elements not normally found in the lunar regolith.

  2. MarsVac: Pneumatic Sampling System for Planetary Exploration

    NASA Astrophysics Data System (ADS)

    Zacny, K.; Mungas, G.; Chu, P.; Craft, J.; Davis, K.

    2008-12-01

    We are proposing a Mars Sample Return scheme whereby a sample of regolith is acquired directly into a Mars Ascent Vehicle using a pneumatic system. Unlike prior developments that used suction to collect fines, the proposed system uses positive pressure to move the regolith. We envisage 3 pneumatic tubes to be embedded inside the 3 legs of the lander. Upon landing, the legs will burry themselves into the regolith and the tubes will fill up with regolith. With one puff of gas, the regolith can be lifted into a sampling chamber onboard of the Mars Ascent Vehicle. An additional chamber can be opened to acquire atmospheric gas and dust. The entire MSR will require 1) an actuator to open/close sampling chamber and 2) a valve to open gas cylinder. In the most recent study related to lunar excavation and funded under the NASA SBIR program we have shown that it is possible lift over 3000 grams of soil with only 1 gram of gas at 1atm. Tests conducted under Mars atmospheric pressure conditions (5 torr). In September of 2008, we will be performing tests at 1/6thg (Moon) and 1/3g (Mars) to determine mass lifting efficiencies in reduced gravities.

  3. Optical effects of regolith processes on S asteroids as simulated by laser impulse alteration of ordinary chondrite

    NASA Technical Reports Server (NTRS)

    Moroz, L. V.; Fisenko, A. V.; Semjonova, L. F.; Pieters, C. M.

    1993-01-01

    The spectral properties of some powdered chondrites and minerals altered by Isser impulse are studied in order to estimate possible optical effects of regolith processes (micrometeoritic bombardment). Gradual reduction of overall reflectance and spectral contrast, the increase of continuum slope, the increase of spectrally derived olivine/pyroxene ratio and Fs content of orthopyroxene with increasing alteration degree show that regolith processes could affect optical properties of surface material more heavily than has been previously appreciated. Ordinary chondrites (OC's) are known to account for 80 percent of observed meteorite falls, but so far no main belt parent bodies have been identified for these meteorites. S-asteroids resemble OC's spectrally, but are characterized by a steeper red continuum unlike that of OC's and their spectrally derived mineralogies are far outside OC range. Attempts were made to explain the spectral mismatch between OC's and S asteroids by some process, which alters optical properties of uppermost regolith. However, the spectral studies of shocked (black) OC's, gas-rich OC's, melted OC's and synthetic metal-rich regoliths derived from OC's demonstrate that such altered OC materials darken, but do not redden.

  4. Impact-induced thermal effects in the lunar and Mercurian regoliths

    NASA Technical Reports Server (NTRS)

    Cintala, Mark J.

    1992-01-01

    Thermal effects of micrometeoroid impact into the regoliths of the moon and Mercury, and some comparisons between the regoliths of the two bodies are presented. The impact calculations used to estimate the volumes of melt and vapor produced in the regoliths of the two bodies are described. An overview of the process of impact metamorphism in a modeled regolith target is presented, in which the roles played by impact velocity and target temperature in determining the quantities of melt and vapor are evaluated. The model impact process and fluxes are combined to estimate the production rates for impact melt and vapor on the two bodies, and the results are compared with those of previous studies. It is concluded that the rates of impact melting and vaporization on Mercury are much greater than on the moon. In a given period of time, a factor of 14 times more melt and 20 times more vapor are produced on Mercury than on the moon. A 'typical' Mercurian microcratering event produces 2.6 times more melt than its lunar counterpart; the flux calculated for Mercury is 5.5 times higher than it is at the moon.

  5. Decameter-Scale Regolith Textures on Mercury

    NASA Astrophysics Data System (ADS)

    Kreslavsky, M. A.; Zharkova, A. Yu.; Head, J. W.

    2018-05-01

    Like on the Moon, regolith gardening smooths the surface. Small craters are in equilibrium. “Elephant hide“ typical on the lunar slopes is infrequent on Mercury. Finely Textured Slope Patches have no analog on the Moon.

  6. Zinnia Germination and Lunar Soil Amendment

    NASA Technical Reports Server (NTRS)

    Reese, Laura

    2017-01-01

    Germination testing was performed to determine the best method for germinating zinnias. This method will be used to attempt to germinate the zinnia seeds produced in space. It was found that seed shape may be critically important in determining whether a seed will germinate or not. The ability of compost and worm castings to remediate lunar regolith simulant for plant growth was tested. It was found that neither treatment effectively improves plant growth in lunar regolith simulant. A potential method of improving lunar regolith simulant by mixing it with arcillite was discovered.

  7. Resource Production on the Moon

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.

    2014-01-01

    A self-sustaining settlement on the moon, or on other airless bodies such as asteroids, will require the ability to refine desired raw materials from available resources, such as lunar or asteroidal regolith. This work will focus on the example case of pro-duction from lunar regolith. The same process sequences could be used at other locations. Stony asteroids typically have regolith similar to that of the moon, and refining of asteroidal material could use the same techniques, adapted for microgravity. Likewise, Martian rock and soil could also be processed by the techniques discussed here.

  8. Diurnal Temperature Regime in the Regolith Surface Layer of the Lagado Planitia Region on Phobos: Model Predictions for Different Seasons

    NASA Astrophysics Data System (ADS)

    Kuzmin, R. O.; Zabalueva, E. V.

    2018-03-01

    The paper contains the data on the thermal and physical characteristic of the surface regolith of the Martian satellite Phobos obtained from the spaceborne remote sensing (with the Mariner 9, Viking, and Mars Global Surveyor orbiters and the Phobos-2 spacecraft) and the results of the numerical modeling of the thermal regime in the surface regolith (on diurnal and seasonal scales) performed for the prospective landing site in the Lagado Planitia region located in the anti-Martian hemisphere of Phobos.

  9. Determining the Water Ice Content of Martian Regolith by Nonlinear Spectral Mixture Modeling

    NASA Technical Reports Server (NTRS)

    Gyalay, S.; Noe Dobrea, E. Z.

    2015-01-01

    In the search for evidence of life, Icebreaker will drill in to the Martian ice-rich regolith to collect samples, which will then be analyzed by an array of instruments designed to identify biomarkers. In addition, drilling into the subsurface will provide the opportunity to assess the vertical distribution of ice to a depth of 1 meter. The purpose of this particular project was to understand the uncertainties involved in the use of the imaging system to constrain the water ice content in regolith samples.

  10. Dehydroxylated clay silicates on Mars: Riddles about the Martian regolith solved with ferrian saponites

    NASA Technical Reports Server (NTRS)

    Burns, Roger G.

    1992-01-01

    Clay silicates, resulting from the chemical weathering of volcanic glasses and basaltic rocks of Mars, are generally believed to be major constituents of the martian regolith and atmospheric dust. Because little attention has been given to the role, if any, of Mg-bearing clay silicates on the martian surface, the crystal chemistry, stability, and reactivity of Mg-Fe smectites are examined. Partially dehydroxylated ferrian saponites are suggested to be major constituents of the surface of Mars, regulating several properties of the regolith.

  11. Constraining Lunar Cold Spot Properties Using Eclipse and Twilight Temperature Behavior

    NASA Astrophysics Data System (ADS)

    Powell, T. M.; Greenhagen, B. T.; Hayne, P. O.; Bandfield, J. L.

    2016-12-01

    Thermal mapping of the nighttime lunar surface by the Diviner instrument on the Lunar Reconnaissance Orbiter (LRO) has revealed anomalous "cold spot" regions surrounding young impact craters. These regions typically show 5-10K lower nighttime temperatures than background regolith. Previous modeling has shown that cold spot regions can be explained by a "fluffing-up" of the top centimeters of regolith, resulting in a layer of lower-density, highly-insulating material (Bandfield et al., 2014). The thickness of this layer is characterized by the H-parameter, which describes the rate of density increase with depth (Vasavada et al., 2012). Contrary to expectations, new Diviner and ground-based telescopic data have revealed that these cold spot regions remain warmer than typical lunar regolith during eclipses and for a short twilight period at the beginning of lunar night (Hayne et al., 2015). These events act on much shorter timescales than the full diurnal day-night cycle, and the surface temperature response is sensitive to the properties of the top few millimeters of regolith. Thermal modeling in this study shows that this behavior can be explained by a profile with higher surface density and higher H-parameter relative to typical regolith. This results in a relative increase in thermal inertia in the top few millimeters of regolith, but decreased thermal inertia at centimeter depth scales. Best-fit surface density and H-parameter values are consistent with the temperature behavior observed during diurnal night as well as early twilight and eclipse scenarios. We interpret this behavior to indicate the presence of small rocks at the surface deposited by granular flow mixing during cold spot formation. This study also shows that eclipse and twilight data can be used as an important constraint in determining the thermophysical properties of lunar regolith. References: Bandfield, et al. (2014), Icarus, 231, 221-231. Hayne, et al. (2015), In Lunar and Planetary Science Conference (Vol. 46, p. 1997). Vasavada, et al. (2012), J. Geophys. Res., 117(E12).

  12. Shallow structure of the InSight 2018 landing site in Elysium Planitia, Mars, from ambient vibration Rayleigh wave ellipticity: A modeling study

    NASA Astrophysics Data System (ADS)

    Knapmeyer-Endrun, B.; Golombek, M.; Ohrnberger, M. M.

    2016-12-01

    The SEIS (Seismic Experiment for Interior Structure) instrument onboard NASA's InSight mission, scheduled to land in November 2018, will be the first seismometer directly deployed on the surface of Mars. From studies on both the Earth and the Moon, it is well known that site amplification in low-velocity sediments, e.g. regolith, on top of more competent rocks has a strong influence on seismic signals, but can also be used to constrain the subsurface structure. Based on orbital data, lab measurements and terrestrial analogues, we construct a model of the shallow sub-surface at the landing site in western Elysium Planitia and simulate the ambient vibration wavefield. We show how Rayleigh wave ellipticity can be extracted from these data and inverted for shallow structure. Using reasonable variations in regolith properties, we do not expect any influence of site resonances on teleseismic quakes recorded by InSight, but recordings of local events will likely be affected. We find that higher mode ellipticity information might be extracted from the data, significantly reducing uncertainties in the inversion. Though the data are most sensitive to properties of the upper-most layer and show a strong trade-off between layer depth and velocity, it is possible to estimate the velocity and thickness of the sub-regolith layer and distinguish between different models by using reasonable constraints on regolith properties. Model parameters are best constrained if either higher mode data can be used or additional constraints on regolith properties, e.g. from analysis of hammer strokes of the HP3 heat flow probe or orbital mapping of regolith thickness from the onset diameter of rocky ejecta craters, are available. In addition, Rayleigh wave ellipticity can differentiate between models with a constant regolith velocity and models with increasing velocity with depth. We also discuss the influence of lander and leveling system mechanical noise on the identification of site resonances.

  13. Near Surface Stratigraphy and Regolith Production in Southwestern Elysium Planitia, Mars: Implications for Hesperian-Amazonian Terrains and the InSight Lander Mission

    NASA Astrophysics Data System (ADS)

    Warner, N. H.; Golombek, M. P.; Sweeney, J.; Fergason, R.; Kirk, R.; Schwartz, C.

    2017-10-01

    The presence of rocks in the ejecta of craters at the InSight landing site in southwestern Elysium Planitia indicates a strong, rock-producing unit at depth. A finer regolith above is inferred by the lack of rocks in the ejecta of 10-m-scale craters. This regolith should be penetrable by the mole of the Heat Flow and Physical Properties Package (HP3). An analysis of the size-frequency distribution (SFD) of 7988 rocky ejecta craters (RECs) across four candidate landing ellipses reveals that all craters >200 m in diameter and {<}750 ± 30 Ma in age have boulder-sized rocks in their ejecta. The frequency of RECs however decreases significantly below this diameter (D), represented by a roll-off in the SFD slope. At 30 m < D < 200 m, the slope of the cumulative SFD declines to near zero at D < 30 m. Surface modification, resolution limits, or human counting error cannot account for the magnitude of this roll-off. Rather, a significant population of <200 m diameter fresh non-rocky ejecta craters (NRECs) here indicates the presence of a relatively fine-grained regolith that prevents smaller craters from excavating the strong rock-producing unit. Depth to excavation relationships and the REC size thresholds indicate the region is capped by a regolith that is almost everywhere 3 m thick but may be as thick as 12 to 18 m. The lower bound of the thickness range is independently confirmed by the depth to the inner crater in concentric or nested craters. The data indicate that 85% of the InSight landing region is covered by a regolith that is at least 3 m thick. The probability of encountering rockier material at depths >3 m by the HP3 however increases significantly due to the increase in boulder-size rocks in the lower regolith column, near the interface of the bedrock.

  14. A Review of Lunar Regolith Excavation Robotic Device Prototypes

    NASA Technical Reports Server (NTRS)

    Mueller, Robert P.; Van Susante, Paul J.

    2011-01-01

    The excavation of lunar regolith is desirable for use as a feedstock for oxygen production processes as well as civil engineering purposes and for the fabrication of parts and structures. This is known as In-Situ Resource Utilization (ISRU). More recently, there has been mounting evidence that water ice exists at the poles of the Moon, buried in the regolith where thermally stable conditions exist. This means that regolith excavation will be required to mine the water ice which is believed to be. mixed in with the regolith, or bonded to it. The mined water ice can then be electrolyzed to produce hydrogen and oxygen propellants which could form the basis of a cis-lunar transportation system using in-situ derived propellants. In 2007, the National Aeronautics & Space Administration (NASA) sponsored a Lunar Regolith Excavation Competition as part of its Centennial Challenges program, The competition was not won and it was held again in 2008 and 2009, when it was won by a university team. A $500,000 prize was awarded to the winning team by NASA. In 2010, NASA continued the competition as a spinoff of the Centennial Challenges, which is restricted to university participation only. This competition is known as the "Lunabotics Mining Competition" and is hosted by NASA at Kennedy Space Center. Twenty three American university teams competed in the 2010 Lunabotics Mining Competition. The competition was held again in May 2011 with over 60 teams registered, including international participation. The competition will be held again in May 2012 at Kennedy Space Center in Florida. . This paper contains a thorough review of the various regolith eX,cavation robotic device prototypes that competed in these NASA competitions, and will. classify the machines and their methods of excavation to document the variety of ideas that were spawned and built to compete at these events. It is hoped that documentation of these robots will serve to help future robotic excavation designers and provide a historical reference for future lunar mining machine endeavors.

  15. Howardite Noble Gases as Indicators of Asteroid Surface Processing

    NASA Technical Reports Server (NTRS)

    Cartwright, J. A.; Mittlefehldt, D. W.; Herrin, J. S.; Ott, U.

    2011-01-01

    The HED (Howardite, Eucrite and Diogenite) group meteorites likely or iginate from the Asteroid 4 Vesta - one of two asteroid targets of NA SA's Dawn mission. Whilst Howardites are polymict breccias of eucriti c and diogenitic material that often contain "regolithic" petrologica l features, neither their exact regolithic nature nor their formation processes are well defined. As the Solar Wind (SW) noble gas compon ent is implanted onto surfaces of solar system bodies, noble gas anal yses of Howardites provides a key indicator of regolithic origin. In addition to SW, previous work by suggested that restricted Ni (300-12 00 micro g/g) and Al2O3 (8-9 wt%) contents may indicate an ancient we ll-mixed regolith. Our research combines petrological, compositional and noble gas analyses to help improve understanding of asteroid reg olith formation processes, which will play an intergral part in the i nterpretation of Dawn mission data. Following compositional and petrological analyses, we developed a regolith grading scheme for our sampl e set of 30 Howardites and polymict Eucrites. In order to test the r egolith indicators suggested by, our 8 selected samples exhibited a r ange of Ni, Al2O3 contents and regolithic grades. Noble gas analyses were performed using furnace stepheating on our MAP 215-50 noble gas mass spectrometer. Of our 8 howardites, only 3 showed evidence of SW noble gases (e.g approaching Ne-20/Ne-22 approximately equals 13.75, Ne-21/Ne-22 approximately equals 0.033). As these samples display low regolithic grades and a range of Ni and Al2O3 contents, so far we are unable to find any correlation between these indicators and "regolit hic" origin. These results have a number of implications for both Ho wardite and Vesta formation, and may suggest complex surface stratigr aphies and surface-gardening processes.

  16. Supercritical Carbon Dioxide Extraction of Coronene in the Presence of Perchlorate for In Situ Chemical Analysis of Martian Regolith.

    PubMed

    McCaig, Heather C; Stockton, Amanda; Crilly, Candice; Chung, Shirley; Kanik, Isik; Lin, Ying; Zhong, Fang

    2016-09-01

    The analysis of the organic compounds present in the martian regolith is essential for understanding the history and habitability of Mars, as well as studying the signs of possible extant or extinct life. To date, pyrolysis, the only technique that has been used to extract organic compounds from the martian regolith, has not enabled the detection of unaltered native martian organics. The elevated temperatures required for pyrolysis extraction can cause native martian organics to react with perchlorate salts in the regolith and possibly result in the chlorohydrocarbons that have been detected by in situ instruments. Supercritical carbon dioxide (SCCO2) extraction is an alternative to pyrolysis that may be capable of delivering unaltered native organic species to an in situ detector. In this study, we report the SCCO2 extraction of unaltered coronene, a representative polycyclic aromatic hydrocarbon (PAH), from martian regolith simulants, in the presence of 3 parts per thousand (ppth) sodium perchlorate. PAHs are a class of nonpolar molecules of astrobiological interest and are delivered to the martian surface by meteoritic infall. We also determined that the extraction efficiency of coronene was unaffected by the presence of perchlorate on the regolith simulant, and that no sodium perchlorate was extracted by SCCO2. This indicates that SCCO2 extraction can provide de-salted samples that could be directly delivered to a variety of in situ detectors. SCCO2 was also used to extract trace native fluorescent organic compounds from the martian regolith simulant JSC Mars-1, providing further evidence that SCCO2 extraction may provide an alternative to pyrolysis to enable the delivery of unaltered native organic compounds to an in situ detector on a future Mars rover. Biomarkers-Carbon dioxide-In situ measurement-Mars-Search for Mars' organics. Astrobiology 16, 703-714.

  17. Thermophysical properties of lunar impact ejecta and their evolution through time

    NASA Astrophysics Data System (ADS)

    Ghent, R. R.; Bandfield, J.; Hayne, P. O.; Tai Udovicic, C.; Carter, L. M.; Paige, D. A.

    2016-12-01

    On the Moon, impact cratering has occurred continuously over the past 4 billion years, and has a profound effect on all aspects of lunar geology. Large impacts excavate large blocks from beneath the regolith, and impacts of sub-cm sized objects rupture and sandblast large ejected fragments and turn them into regolith. The regolith, in turn, is space weathered and aged by the impact of micrometeorites, together with exposure to solar wind. The state of impact-related materials at any given site can thus be interpreted in the context of relative or absolute age, and can provide information about the rates of geological processes. Here, we report on observations of the thermophysical properties of lunar impact ejecta from the Lunar Reconnaissance Orbiter Diviner thermal radiometer. Nighttime thermal IR data are sensitive to the abundance of meter-scale rocks at the surface, and to variations in the density structure of the upper meter of the regolith. Comparison of these thermal observations with those from radar instruments allows us to distinguish between large ejecta at the surface and those buried or suspended in the upper 10 m of regolith, and thus to examine the evolution of these two ejecta populations ejecta through time. We have previously found that the surface ejecta rocks associated with large craters break down at a quantifiable rate, and that rocky surface ejecta disappear completely in 1.5 Gyr. Here, we show that rocks buried within the upper m of regolith, detected by radar, can remain undisturbed by surface processes for >3 Gyr. We also investigate the thermophysical properties of radar-dark haloes, comprised of fine-grained distal ejecta, and find that they also persist for long periods (> 3 Gyr). Thus, the surface rockiness of a given ejecta deposit can be used to determine its age. Current work is focusing on exploiting the state of preservation of buried ejecta to constrain the rate of regolith overturn.

  18. Insights into Interactions of Water Ice with Regolith under Simulated Martian Conditions.

    NASA Astrophysics Data System (ADS)

    Chittenden, Julie; Chevrier, V.; Sears, D. W.; Roe, L. A.; Bryson, K.; Billingsly, L.; Hanley, J.

    2006-09-01

    In order to understand the diffusion process of water vapor through regolith, we have investigated the sublimation process of subsurface ice under varying depths of JSC Mars-1 soil simulant under martian conditions. Measurements were made at 0oC and 5.25 Torr in a CO2 atmosphere. We corrected for variations in temperature of the ice and the difference in gravity of Mars in relation to the Earth. Our results show that for depths up to 40 mm the process is mainly diffusion controlled and that for thicker regolith layers, desorption becomes the main process. After correction for the effect of desorption, we observed a decrease in sublimation rate from 0.625 ± 0.073 mm.h-1 at 5 mm of soil to 0.187 ± 0.093 mm.h-1 for 200 mm of soil. To characterize the diffusion process, we use the Farmer model (1976), which hypothesizes that the sublimation rate is equal to the diffusion coefficient divided by the soil depth. The derived diffusion coefficient from this data is 2.52 ± 0.55 mm2.h-1, or 7.0 ± 1.5 x 10-10 m2.s-1. Knowing the diffusion coefficient in the regolith, we can calculate the survival time, κ, of a layer of ice under a regolith layer which is given by τ = liceL/D, where lice is the thickness of the ice layer. Using this equation, we find that a 10 cm-thick layer of ice buried under 1 m of regolith would last for more than 4 years at 0oC. Therefore, our study indicates that the transport of water through a regolith layer is a complex multi-faceted process that is readily quantified by laboratory investigations. This is especially important in interpreting previous theoretical models and in understanding in situ observations to be performed by martian landers such as Phoenix. The W.M. Keck Foundation funded this research.

  19. Drilling Regolith: Why Is It So Difficult?

    NASA Astrophysics Data System (ADS)

    Schmitt, H. H.

    2017-10-01

    The Apollo rotary percussive drill system penetrated the lunar regolith with reasonable efficiency; however, extraction of the drill core stem proved to be very difficult on all three missions. Retractable drill stem flutes may solve this problem.

  20. Using Lunar Regolith for Organics: Plant Growth Test Using Soil Analogues

    NASA Astrophysics Data System (ADS)

    Kołodziejczyk, A.; Vos, H. C.; Harasymczuk, M.; Kraiński, M.; Foing, B. H.

    2017-05-01

    Plant development depends on environmental factors such light, humidity and temperature, seed quality, contaminations, and soil type. We study the use of lunar regolith simulants from Eifel volcanic region on the growth of plants.

  1. Workshop on Thermal Emission Spectroscopy and Analysis of Dust, Disk, and Regoliths

    NASA Technical Reports Server (NTRS)

    Sprague, Ann L. (Editor); Lynch, David K. (Editor); Sitko, Michael (Editor)

    1999-01-01

    This volume contains abstracts that have been accepted for presentation at the workshop on Thermal Emission Spectroscopy and analysis of Dust, Disks and Regoliths, held April 28-30, 1999, in Houston Texas.

  2. Brazil Nuts on Eros: Size-Sorting of Asteroid Regolith

    NASA Technical Reports Server (NTRS)

    Asphaug, E.; King, P. J.; Swift, M. R.; Merrifield, M. R.

    2001-01-01

    We consider the hypothesis that frequent cratering produces size- or compositionally-sorted asteroid regolith, affecting the structure, texture, and in extreme cases the shape of asteroids. Additional information is contained in the original extended abstract.

  3. Numerical simulations of regolith sampling processes

    NASA Astrophysics Data System (ADS)

    Schäfer, Christoph M.; Scherrer, Samuel; Buchwald, Robert; Maindl, Thomas I.; Speith, Roland; Kley, Wilhelm

    2017-07-01

    We present recent improvements in the simulation of regolith sampling processes in microgravity using the numerical particle method smooth particle hydrodynamics (SPH). We use an elastic-plastic soil constitutive model for large deformation and failure flows for dynamical behaviour of regolith. In the context of projected small body (asteroid or small moons) sample return missions, we investigate the efficiency and feasibility of a particular material sampling method: Brushes sweep material from the asteroid's surface into a collecting tray. We analyze the influence of different material parameters of regolith such as cohesion and angle of internal friction on the sampling rate. Furthermore, we study the sampling process in two environments by varying the surface gravity (Earth's and Phobos') and we apply different rotation rates for the brushes. We find good agreement of our sampling simulations on Earth with experiments and provide estimations for the influence of the material properties on the collecting rate.

  4. Sputtering of Lunar Regolith Simulant by Protons and Multicharged Heavy Ions at Solar Wind Energies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Meyer, Fred W; Harris, Peter R; Taylor, C. N.

    2011-01-01

    We report preliminary results on sputtering of a lunar regolith simulant at room temperature by singly and multiply charged solar wind ions using quadrupole and time-of-flight (TOF) mass spectrometry approaches. Sputtering of the lunar regolith by solar-wind heavy ions may be an important particle source that contributes to the composition of the lunar exosphere, and is a possible mechanism for lunar surface ageing and compositional modification. The measurements were performed in order to assess the relative sputtering efficiency of protons, which are the dominant constituent of the solar wind, and less abundant heavier multicharged solar wind constituents, which have highermore » physical sputtering yields than same-velocity protons, and whose sputtering yields may be further enhanced due to potential sputtering. Two different target preparation approaches using JSC-1A AGGL lunar regolith simulant are described and compared using SEM and XPS surface analysis.« less

  5. Modeling Joule Heating Effect on Lunar O2 Generation via Electrolytic Reduction.

    NASA Technical Reports Server (NTRS)

    Dominquez, Jesus; Poizeau, Sophie; Sibille, Laurent

    2009-01-01

    Kennedy Space Center is leading research work on lunar O2 generation via electrolytic reduction of regolith; the metal oxide present in the regolith is dissociated in oxygen anions and metal cations leading to the generation of gaseous oxygen at the anode and liquid metal at the cathode. Electrical resistance of molten regolith is high, leading to heating of the melt when electrical current is applied between the electrodes (Joule heating). The authors have developed a 3D model using a rigorous approach for two coupled physics (thermal and electrical potential) to not only study the effect of Joule heating on temperature distribution throughout the molten regolith but also to evaluate and optimize the design of the electrolytic cells. This paper presents the results of the thermal analysis performed on the model and used to validate the design of the electrolytic cell.

  6. A new experimental capability for the study of regolith surface physical properties to support science, space exploration, and in situ resource utilization (ISRU)

    NASA Astrophysics Data System (ADS)

    Dreyer, Christopher B.; Abbud-Madrid, Angel; Atkinson, Jared; Lampe, Alexander; Markley, Tasha; Williams, Hunter; McDonough, Kara; Canney, Travis; Haines, Joseph

    2018-06-01

    Many surfaces found on the Moon, asteroids, Mars, moons, and other planetary bodies are covered in a fine granular material known as regolith. Increased knowledge of the physical properties of extraterrestrial regolith surfaces will help advance the scientific knowledge of these bodies as well as the development of exploration (e.g., instrument and robotic) and in situ resource utilization (ISRU) systems. The Center for Space Resources at the Colorado School of Mines as part of the Institute for Modeling Plasma, Atmospheres, and Cosmic Dust of NASA's Solar System Exploration Research Virtual Institute has developed a novel system, called the ISRU Experimental Probe (IEP) that can support studies of dry and icy regolith from -196 to 150 °C and pressure from laboratory ambient pressure to 10-7 Torr. The IEP system and proof-of-concept results are presented in this paper.

  7. Radiation protection using Martian surface materials in human exploration of Mars

    NASA Technical Reports Server (NTRS)

    Kim, M. H.; Thibeault, S. A.; Wilson, J. W.; Heilbronn, L.; Kiefer, R. L.; Weakley, J. A.; Dueber, J. L.; Fogarty, T.; Wilkins, R.

    2001-01-01

    To develop materials for shielding astronauts from the hazards of GCR, natural Martian surface materials are considered for their potential as radiation shielding for manned Mars missions. The modified radiation fluences behind various kinds of Martian rocks and regolith are determined by solving the Boltzmann equation using NASA Langley's HZETRN code along with the 1977 Solar Minimum galactic cosmic ray environmental model. To develop structural shielding composite materials for Martian surface habitats, theoretical predictions of the shielding properties of Martian regolith/polyimide composites has been computed to assess their shielding effectiveness. Adding high-performance polymer binders to Martian regolith to enhance structural properties also enhances the shielding properties of these composites because of the added hydrogenous constituents. Heavy ion beam testing of regolith simulant/polyimide composites is planned to validate this prediction. Characterization and proton beam tests are performed to measure structural properties and to compare the shielding effects on microelectronic devices, respectively.

  8. Analysis of regolith electromagnetic scattering as constrained by high resolution Earth-based measurements of the lunar microwave emission

    NASA Technical Reports Server (NTRS)

    Keihm, S. J.

    1983-01-01

    When high resolution measurements of the phase variation of the lunar disk center brightness temperature revealed that in situ regolith electrical losses were larger than those measured on returned samples by a factor of 1.5 to 2.0 at centimeter wavelengths, the need for a refinement of the regolith model to include realistic treatment of scattering effects was identified. Two distinct scattering regimes are considered: vertial variations in dielectric constant and volume scattering due to subsurface rock fragments. Models of lunar regolith energy transport processes are now at the state for which a maximum scientific return could be realized from a lunar orbiter microwave mapping experiment. A detailed analysis, including the effects of scattering produced a set of nominal brightness temperature spectra for lunar equatorial regions, which can be used for mapping as a calibration reference for mapping variations in mineralogy and heat flow.

  9. Climatic implications of the simultaneous presence of CO2 and H2O in the Martian regolith

    NASA Technical Reports Server (NTRS)

    Zent, A. P.

    1992-01-01

    The current paradigm for quasi-periodic climate change on Mars holds that perhaps a few hundred millibars of CO2 are available for exchange between the atmosphere and regolith, and that a vast majority of that CO2 is presently absorbed into the regolith. The CO2 is partitioned between the regolith and atmosphere according to an equilibrium adsorptive relationship. If the atmospheric pressure exceeds the frost point at or near the poles, then quasi-permanent polar caps form and buffer the atmospheric pressure. This model was developed based upon laboratory studies of CO2 adsorption where no other adsorbates are present. We will conduct laboratory measurements of the simultaneous adsorption of H2O and CO2 under Mars-like conditions, and develop numerical expressions for use in climate modeling based upon our results.

  10. Joule-Heated Molten Regolith Electrolysis Reactor Concepts for Oxygen and Metals Production on the Moon and Mars

    NASA Technical Reports Server (NTRS)

    Sibille, Laurent; Dominques, Jesus A.

    2012-01-01

    The maturation of Molten Regolith Electrolysis (MRE) as a viable technology for oxygen and metals production on explored planets relies on the realization of the self-heating mode for the reactor. Joule heat generated during regolith electrolysis creates thermal energy that should be able to maintain the molten phase (similar to electrolytic Hall-Heroult process for aluminum production). Self-heating via Joule heating offers many advantages: (1) The regolith itself is the crucible material, it protects the vessel walls (2) Simplifies the engineering of the reactor (3) Reduces power consumption (no external heating) (4) Extends the longevity of the reactor. Predictive modeling is a tool chosen to perform dimensional analysis of a self-heating reactor: (1) Multiphysics modeling (COMSOL) was selected for Joule heat generation and heat transfer (2) Objective is to identify critical dimensions for first reactor prototype.

  11. Responses of chemical erosion rates to transient perturbations in physical erosion rates, and implications for relationships between chemical and physical erosion rates in regolith-mantled hillslopes

    NASA Astrophysics Data System (ADS)

    Ferrier, Ken L.; West, Nicole

    2017-09-01

    Understanding the relationship between chemical erosion rates (W) and physical erosion rates (E) is of wide interest due to their roles in driving landscape evolution, supplying nutrients to soils and streams, and modulating the global carbon cycle. Measured relationships between W and E vary around the globe, with some regions exhibiting positive correlations between W and E, some negative correlations, and others no correlation within uncertainty. Here we use a numerical model for mineral weathering in well-mixed ridgetop regolith to explore how complex W- E relationships can be generated by simple transient perturbations in E. We show that a Gaussian perturbation in E can produce positive or negative responses in W, and can result in a variety of hysteresis loops - clockwise, counterclockwise, or figure-eight - in plots of W against E. The nature of the transient response depends on the shape of the steady-state W- E relationship, which is set by regolith mineralogy, and the ratio of E to the maximum possible regolith production rate. The response time of W is controlled by the response time of soluble mineral concentrations at low E, where soluble mineral concentrations are low, and by the response time of regolith thickness at high E, where regolith thickness is low. These complex W- E relationships arise in the absence of variations in climate and lithology, which suggests that transients may account for some of the observed differences in W- E relationships among field sites, even among sites that share the same climate and lithology.

  12. High-resolution Earth-based lunar radar studies: Applications to lunar resource assessment

    NASA Technical Reports Server (NTRS)

    Stacy, N. J. S.; Campbell, D. B.

    1992-01-01

    The lunar regolith will most likely be a primary raw material for lunar base construction and resource extraction. High-resolution radar observations of the Moon provide maps of radar backscatter that have intensity variations generally controlled by the local slope, material, and structural properties of the regolith. The properties that can be measured by the radar system include the dielectric constant, density, loss tangent, and wavelength scale roughness. The radar systems currently in operation at several astronomical observatories provide the ability to image the lunar surface at spatial resolutions approaching 30 m at 3.8 cm and 12.6 cm wavelengths and approximately 500 m at 70 cm wavelength. The radar signal penetrates the lunar regolith to a depth of 10-20 wavelengths so the measured backscatter contains contributions from the vacuum-regolith interface and from wavelength-scale heterogeneities in the electrical properties of the subsurface material. The three wavelengths, which are sensitive to different scale structures and scattering volumes, provide complementary information on the regolith properties. Aims of the previous and future observations include (1) analysis of the scattering properties associated with fresh impact craters, impact crater rays, and mantled deposits; (2) analysis of high-incidence-angle observations of the lunar mare to investigate measurement of the regolith dielectric constant and hence porosity; (3) investigation of interferometric techniques using two time-delayed observations of the same site, observations that require a difference in viewing geometry less than 0.05 deg and, hence, fortuitous alignment of the Earth-Moon system when visible from Arecibo Observatory.

  13. Nanomorphology of Itokawa regolith particles: Application to space-weathering processes affecting the Itokawa asteroid

    NASA Astrophysics Data System (ADS)

    Matsumoto, Toru; Tsuchiyama, Akira; Uesugi, Kentaro; Nakano, Tsukasa; Uesugi, Masayuki; Matsuno, Junya; Nagano, Takashi; Shimada, Akira; Takeuchi, Akihisa; Suzuki, Yoshio; Nakamura, Tomoki; Nakamura, Michihiko; Gucsik, Arnold; Nagaki, Keita; Sakaiya, Tatsuhiro; Kondo, Tadashi

    2016-08-01

    The morphological properties of 26 regolith particles from asteroid Itokawa were observed using scanning electron microscopes in combination with an investigation of their three-dimensional shapes obtained through X-ray microtomography. Surface observations of a cross section of the LL5 chondrite, and of crystals of olivine and pyroxene, were also performed for comparison. Some Itokawa particles have surfaces corresponding to walls of microdruses in the LL chondrite, where concentric polygonal steps develop and euhedral or subhedral grains exist. These formed through vapor growth owing to thermal annealing, which might have been caused by thermal metamorphism or shock-induced heating in Itokawa's parent body. Most of the Itokawa particles have more or less fractured surfaces, indicating that they were formed by disaggregation, probably caused by impacts. Itokawa particles with angular and rounded edges observed in computed tomography images are associated with surfaces exhibiting clear and faint structures, respectively. These surfaces can be interpreted by invoking different degrees of abrasion after regolith formation. A possible mechanism for the abrasion process is grain migration caused by impact-driven seismic waves. Space-weathered rims with blisters are distributed heterogeneously across the Itokawa regolith particles. This heterogeneous distribution can be explained by particle motion and fracturing, combined with solar-wind irradiation of the particle surfaces. The regolith activity-including grain motion, fracturing, and abrasion-might effectively act as refreshing process of Itokawa particles against space-weathered rim formation. The space-weathering processes affecting Itokawa would have developed simultaneously with space-weathered rim formation and regolith particle refreshment.

  14. The Magnesium Mystery of the Apollo 11 Regolith

    NASA Technical Reports Server (NTRS)

    Korotev, Randy L.

    2000-01-01

    The Apollo 11 regolith is enriched in Mg compared to mixtures of local mare basalts and feldspathic highland material that accounts for other elements. Using mass-balance constraints, we cannot identify the component, but its abundance is approx. 8%.

  15. Aqueous extracts of a Mars analogue regolith that mimics the Phoenix landing site do not inhibit spore germination or growth of model spacecraft contaminants Bacillus subtilis 168 and Bacillus pumilus SAFR-032

    NASA Astrophysics Data System (ADS)

    Nicholson, Wayne L.; McCoy, Lashelle E.; Kerney, Krystal R.; Ming, Douglas W.; Golden, D. C.; Schuerger, Andrew C.

    2012-08-01

    Because Mars is a primary target for life detection and habitability assessment missions, its exploration is also by necessity a Planetary Protection issue. The recent finding of significant levels of perchlorate (ClO4-) in regolith sampled from the Phoenix landing site raises the question of its potential biotoxicity to putative indigenous martian life, microbial forward contaminants from Earth, or future human visitors. To address this issue, an analogue regolith was constructed based on regolith chemistry data from the Phoenix landing site. A Mars Aqueous Regolith Extract (MARE) was prepared from the Phoenix analogue regolith and analyzed by ion chromatography. The MARE contained (mg/L) the cations Na+ (1411 ± 181), Mg2+ (1051 ± 160), Ca2+ (832 ± 125), and K+ (261 ± 29), and the anions SO42-(5911±993), ClO4-(5316±1767), Cl(171±25) and F- (2.0 ± 0.4). Nitrogen-containing species NO3-(773±113) and NO2-(6.9±2.3) were also present as a result of regolith preparation procedures, but their relevance to Mars is at present unknown. The MARE was tested for potential toxic effects on two model spacecraft contaminants, the spore-forming bacteria Bacillus subtilis strain 168 and Bacillus pumilus strain SAFR-032. In B. subtilis, spore germination and initial vegetative growth (up to ˜5 h) was not inhibited in a rich complex medium prepared with the MARE, but growth after 5 h was significantly suppressed in medium prepared using the MARE. Both B. subtilis and B. pumilus exhibited significantly higher rates of spore germination and growth in the MARE vs. DW with no additions (likely due to endogenous spore nutrients), but germination and growth was further stimulated by addition of glucose and a combination of buffered inorganic salts (K2HPO4, KH2PO4, (NH4)2SO4, and MgSO4). The data indicate that the aqueous environment in the regolith from the Phoenix landing site containing high levels of perchlorate does not pose a significant barrier to growth of putative forward contaminants such as B. subtilis and B. pumilus under Earth laboratory conditions.

  16. Evolution of gas-rich meteorites: Clues from cosmogenic nuclides

    NASA Technical Reports Server (NTRS)

    Goswami, J. N.

    1986-01-01

    The evolution of gas-rich meteorites in general, and the setting in which the observed solar-wind, solar-flare irradiation records were imprinted in individual components of these meteorites are understood only in qualitative terms, although contrary viewpoints do exist. The regolith irradiation hypothesis, bolstered by the observations of irradiation features in lunar regolith materials, similar to those observed in gas-rich meteorites, is accepted by many workers in this field. However, a close analysis of the problem suggests that the regolith irradiation may not be the dominant mode in producing the observed precompaction irradiation features in the gas-rich meteorites.

  17. Petrology of the Cangas de Onis and nulles regolith breccias Implications for parent body history

    NASA Technical Reports Server (NTRS)

    Williams, C. V.; Rubin, A. E.; Keil, K.; San Miguel, A.

    1985-01-01

    The present study of the Cangas de Onis and Nulles H chondrite regolith breccias indicates that the minerals in the matrices and equilibrated clasts have essentially the same compositional distributions, so that much of the material in the castic matrix would have to have been derived from the impact comminution of clats. The apparently exclusive occurrence of H6 clasts in Cangas de Onis, and H4 clasts in Nulles, suggests that, at the locations where these breccias formed, the regolith predominantly consisted of H6 and H4 material, respectively.

  18. ATHLETE as a Mobile ISRU and Regolith Construction Platform

    NASA Technical Reports Server (NTRS)

    Howe, A. Scott; Wilcox, Brian; Barmatz, Martin; Voecks, Gerald

    2016-01-01

    The All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) robotic mobility platform can provide precision positioning and mobility for site preparation and regolith construction needs. ATHLETE is a multi-use platform designed to use swap-out tools and implements that can be applied to any number of tasks that need precision limb manipulation or mobility. Major capabilities include off-loading habitats, transporting surface assets, robotically assembling outposts from multiple mission manifests, and supporting science and technology objectives. This paper describes conceptual approaches for supporting NASA regolith construction research, such as additive construction, modular brick and panel factory, and mobile ISRU platform.

  19. Lunar regolith bagging system

    NASA Technical Reports Server (NTRS)

    Cannon, Reuben; Henninger, Scott; Levandoski, Mark; Perkins, Jim; Pitchon, Jack; Swats, Robin; Wessels, Roger

    1990-01-01

    A design of a lunar regolith bag and bagging system is described. The bags of regolith are to be used for construction applications on the lunar surface. The machine is designed to be used in conjunction with the lunar SKITTER currently under development. The bags for this system are 1 cu ft volume and are made from a fiberglass composite weave. The machinery is constructed mostly from a boron/aluminum composite. The machine can fill 120 bags per hour and work for 8 hours a day. The man hours to machine hours ratio to operate the machine is .5/8.

  20. Simulant Materials of Lunar Dust: Requirements and feasibility

    NASA Technical Reports Server (NTRS)

    Sibille, L.

    2005-01-01

    As NASA turns its exploration ambitions towards the Moon once again, the research and development of new technologies for lunar operations face the challenge of meeting the milestones of a fast-pace schedule, reminiscent of the 1960 s Apollo program. While the lunar samples returned by the Apollo and Luna missions have revealed much about the Moon, these priceless materials exist in too scarce quantities to be used for technology development and testing. The need for mineral materials chosen to simulate the characteristics of lunar regoliths is a pressing issue that must be addressed today through the collaboration of scientists, engineers and program managers. While the larger size fraction of the lunar regolith has been reproduced in several simulants in the past, little attention has been paid to the fines fraction, commonly refered to as lunar dust. As reported by McKay, this fraction of the lunar regolith below 20 microns can represent upto 30% by mass of the total regolith mass. The issue of reproducing the properties of these fines for research and technology development purposes was addressed by the recently held Workshop on Lunar Regolith Simulant Materials at Marshall Space Flight Center. Preliminary conclusions from the workshop and con- side-rations concerning the feasibility of producing such materials will be presented here.

  1. Asteroid Regolith Simulants: Development, Characteristics, and Testing

    NASA Astrophysics Data System (ADS)

    Britt, D. T.

    2015-12-01

    As part of a NASA Small Business Innovation Research (SBIR) award to the University of Central Florida and Deep Space Industries, we are developing a family of asteroid regolith simulants based on meteorite mineralogies but using terrestrial materials, to support NASAs exploration goals for asteroids. We are planning on developing five types of simulant based on the following meteorite types: CI-carbonaceous chondrite, CM-carbonaceous chondrite, Tagish Lake, L-ordinary chondrite, and iron. To the greatest extent reasonable (based on input costs and health/safety) we will duplicate the mineralogy, chemistry, oxidation state, hydration state, and particle size distribution found in regolith meteorites of each type. The major limitations on the fidelity of simulant will be health and safety issues for the users of the simulants. For example, much of the organic component of volatile-rich carbonaceous chondrites are in the form of Polycyclic Aromatic Hydrocarbons (PAHs). These are essentially combustion residues, possibly of complex regolith processing, with more carbon atoms than hydrogen. However, many PAHs are toxic, carcinogenic, and/or mutagenic. Several are banned in the European Union and California. This sort of material would endanger users, be impossible to distribute, and not make a useable regolith simulant. There are several reasonable, no-toxic alternatives to PAHs. We will report on the status of simulant development and the progress of our validation experiments.

  2. Martian Regolith for Plant-Based Life Support

    NASA Astrophysics Data System (ADS)

    Visscher, A. M.; Seal, C. E.; Pritchard, H. W.

    2018-04-01

    As plants could play key roles in future long-term life support systems on Mars, it is crucial to know whether in situ resources such as martian regolith are suitable for seed germination and subsequent growth of a wide variety of plant species.

  3. On the Relationship Between Site Geology and the Distribution of Surface Regolith Compositions at the Apollo Sites

    NASA Technical Reports Server (NTRS)

    Korotev, Randy L.

    2000-01-01

    Some considerations are discussed on how information on site geology can be obtained from the distribution of data points on 2-element plots of composition of lunar regolith samples collected along a traverse.

  4. Lunar Polar Environmental Testing: Regolith Simulant Conditioning

    NASA Technical Reports Server (NTRS)

    Kleinhenz, Julie

    2014-01-01

    As ISRU system development approaches flight fidelity, there is a need to test hardware in relevant environments. Extensive laboratory and field testing have involved relevant soil (lunar regolith simulants), but the current design iterations necessitate relevant pressure and temperature conditions. Including significant quantities of lunar regolith simulant in a thermal vacuum chamber poses unique challenges. These include facility operational challenges (dust tolerant hardware) and difficulty maintaining a pre-prepared soil state during pump down (consolidation state, moisture retention).For ISRU purposes, the regolith at the lunar poles will be of most interest due to the elevated water content. To test at polar conditions, the regolith simulant must be doped with water to an appropriate percentage and then chilled to cryogenic temperatures while exposed to vacuum conditions. A 1m tall, 28cm diameter bin of simulant was developed for testing these simulant preparation and drilling operations. The bin itself was wrapped with liquid nitrogen cooling loops (100K) so that the simulant bed reached an average temperature of 140K at vacuum. Post-test sampling was used to determine desiccation of the bed due to vacuum exposure. Depth dependent moisture data is presented from frozen and thawed soil samples.Following simulant only evacuation tests, drill hardware was incorporated into the vacuum chamber to test auguring techniques in the frozen soil at thermal vacuum conditions. The focus of this testing was to produce cuttings piles for a newly developed spectrometer to evaluate. This instrument, which is part of the RESOLVE program science hardware, detects water signatures from surface regolith. The drill performance, behavior of simulant during drilling, and characteristics of the cuttings piles will be offered.

  5. Angular Scattering Reflectance and Polarization Measurements of Candidate Regolith Materials Measured in the Laboratory

    NASA Astrophysics Data System (ADS)

    Nelson, Robert M.; Boryta, Mark D.; Hapke, Bruce W.; Shkuratov, Yuriy; Vandervoort, Kurt; Vides, Christina L.

    2016-10-01

    The reflectance and polarization of light reflected from a solar system object indicates the chemical and textural state of the regolith. Remote sensing data are compared to laboratory angular scattering measurements and surface properties are determined.We use a Goniometric Photopolarimeter (GPP) to make angular reflectance and polarization measurements of particulate materials that simulate planetary regoliths. The GPP employs the Helmholtz Reciprocity Principle ( 2, 1) - the incident light is linearly polarized - the intensity of the reflected component is measured. The light encounters fewer optical surfaces improving signal to noise. The lab data are physically equivalent to the astronomical data.Our reflectance and polarization phase curves of highly reflective, fine grained, media simulate the regolith of Jupiter's satellite Europa. Our lab data exhibit polarization phase curves that are very similar to reports by experienced astronomers (4). Our previous reflectance phase curve data of the same materials agree with the same astronomical observers (5). We find these materials exhibit an increase in circular polarization ratio with decreasing phase angle (3). This suggests coherent backscattering (CB) of photons in the regolith (3). Shkuratov et al.(3) report that the polarization properties of these particulate media are also consistent with the CB enhancement process (5). Our results replicate the astronomical data indicating Europa's regolith is fine-grained, high porous with void space exceeding 90%.1. Hapke, B. W. (2012). ISBN 978-0-521-88349-82. Minnaert, M. (1941).Asrophys. J., 93, 403-410.3. Nelson, R. M. et al. (1998). Icarus, 131, 223-230.4. Rosenbush, V. et al. (2015). ISBN 978-1-107-04390-9, pp 340-359.5. Shkuratov, Yu. et al. (2002) Icarus 159, 396-416.

  6. Topographic imprint on chemical weathering in deeply weathered soil-mantled landscapes (southern Brazil)

    NASA Astrophysics Data System (ADS)

    Vanacker, Veerle; Schoonejans, Jerome; Ameijeiras-Marino, Yolanda; Opfergelt, Sophie; Minella, Jean

    2017-04-01

    The regolith mantle is defined as the thin layer of unconsolidated material overlaying bedrock that contributes to shape the Earth's surface. The development of the regolith mantle in a landscape is the result of in-situ weathering, atmospheric input and downhill transport of weathering products. Bedrock weathering - the physical and chemical transformations of rock to soil - contributes to the vertical development of the regolith layer through downward propagation of the weathering front. Lateral transport of soil particles, aggregates and solutes by diffusive and concentrated particle and solute fluxes result in lateral redistribution of weathering products over the hillslope. In this study, we aim to expand the empirical basis on long-term soil evolution at the landscape scale through a detailed study of soil weathering in subtropical soils. Spatial variability in chemical mass fluxes and weathering intensity were studied along two toposequences with similar climate, lithology and vegetation but different slope morphology. This allowed us to isolate the topographic imprint on chemical weathering and soil development. The toposequences have convexo-concave slope morphology, and eight regolith profiles were analysed involving the flat upslope, steep midslope and flat toeslope part. Our data show a clear topographic imprint on soil development. Along hillslope, the chemical weathering intensity of the regolith profiles increases with distance from the crest. In contrast to the upslope positions, the soils in the basal concavities develop on in-situ and transported regolith. While the chemical weathering extent on the slope convexities (the upslope profiles) is similar for the steep and gentle toposequence, there is a clear difference in the rate of increase of the chemical weathering extent with distance from the crest. The increase of chemical weathering extent along hillslope is highest for the steep toposequence, suggesting that topography enhances soil particle, aggregate and solute fluxes.

  7. Feedbacks among O2 and CO2 in deep soil gas, oxidation of ferrous minerals, and fractures: A hypothesis for steady-state regolith thickness

    NASA Astrophysics Data System (ADS)

    Kim, Hyojin; Stinchcomb, Gary; Brantley, Susan L.

    2017-02-01

    O2 and CO2, the two essential reactants in weathering along with water and minerals, are important in deep regolith development because they diffuse to weathering fronts at depth. We monitored the dynamics of these gas concentrations in the hand-augerable zone on three ridgetops-one on granite and two on diabase-in Virginia (VA) and Pennsylvania (PA), U.S.A. and related the gas chemistry to regolith development. The VA granite and the PA diabase protoliths were more deeply weathered than the VA diabase. We attribute this to high protolith fracture density. The pO2 and pCO2 measurements of these more fractured sites displayed the characteristics of aerobic respiration year round. In contrast, the relation of pO2 versus pCO2 on the more massive VA diabase is consistent with seasonal changes in the dominant electron acceptor from O2 to Fe(III), likely regulated by the expansion/contraction of nontronite in the soil BC horizon. These observations suggest that the fracture density is a first order control on deep regolith gas chemistry. However, fractures can be present in protolith but also can be caused by oxidation of ferrous minerals. We propose that subsurface pO2 and weathering-induced fracturing can create positive feedbacks in some lithologies that cause regolith to thicken while nonetheless maintaining aerobic respiration at depth. In contrast, in the absence of weathering-induced fracturing and depletion of pO2, a negative feedback that may be modulated by soil micro-biota ultimately results in thin regolith. These feedbacks may have been important in weathering systems over much of earth's history.

  8. Tracing mineral weathering reactions in the critical zone using Mg, Ca, and Sr isotopes, Luquillo Mountains, Puerto Rico

    NASA Astrophysics Data System (ADS)

    Buss, H. L.; White, A. F.; Vivit, D.; Bullen, T. D.; Blum, A. E.; Dessert, C.; Gaillardet, J.

    2008-12-01

    Mineral weathering in the critical zone directly impacts the availability of many important soil nutrients. As part of the USGS Water Energy and Biogeochemical Budgets (WEBB) program and the Critical Zone Exploration Network, we are investigating mineral nutrient distributions and fluxes in depth profiles (to 16 m) at five sites in the Bisley 1 catchment in the Luquillo Mountains of Puerto Rico. The Bisley 1 catchment contains a thick regolith developed on marine bedded, andesitic, volcaniclastic bedrock. Pore waters were sampled as a function of depth from nested suction water samplers. Pore water chemistry was analyzed and compared to total chemistry of solid samples taken from augered cores. Mg, Ca and Sr isotope ratios were measured of the pore waters at the Institut de Physique du Globe de Paris (Mg) and at the USGS in Menlo Park, CA (Ca, Sr). The Mg isotope ratios increase with increasing depth from δ26Mg = -0.772 at the surface to - 0.267 at depth, relative to the DSM3 standard. Sr isotope ratios vary from 0.70922 to 0.71016 87Sr/86Sr, with no discernible depth trend. The regolith is highly weathered and is depleted in primary minerals (except quartz) with respect to bedrock. Volumetric strain, calculated with respect to quartz, indicates approximately 25% volume collapse occurred relative to the original volume of the bedrock. Plagioclase, chlorite, pyroxene, and amphibole weather at the bedrock-regolith interface. The regolith contains quartz, kaolinite, other clays, and iron and manganese oxides. Increasing solid and pore water Mg concentrations and δ26Mg with depth likely indicate a two step weathering process wherein high-Mg chlorite dissolves at the bedrock-regolith interface and forms Mg-containing secondary clays and oxides, which then dissolve within the regolith profile.

  9. Impact-Driven Overturn of Lunar Regolith: A Refreshed Approach

    NASA Astrophysics Data System (ADS)

    Costello, E.; Ghent, R. R.; Lucey, P. G.; Tai Udovicic, C. J.

    2016-12-01

    Meteoritic impactors churn up lunar regolith, the layer of heterogeneous grains that covers nearly the entire lunar surface to a depth of tens to hundreds of meters, and affect its geologic, petrographic and chemical makeup. An understanding of the physical characteristics of the regolith and how they change through time is fundamentally important to our ability to interpret underlying geological processes from surface observations. Characterizing impact-driven regolith overturn in particular could help us understand the lifetime of rays, ejecta blankets, and stratigraphic layering. Several probabilistic models exist that describe the meteoritic impact-driven overturn process, including that presented by Gault et. al. in their paper `Mixing of the Lunar Regolith.' We re-visit this oft-cited model, updating the constants used with more modern laboratory impact experiments and time variable meteoritic flux estimates. Further, we compare the results of Gault's model to new approaches using remote sensing datasets and Monte Carlo cratering simulations that include conditions Gault's model did not such as the erosion, seismic settling, and degradation that result from the superposition of craters. From this work we present an updated understanding of overturn as a function of time and depth. Gault et. al. showed that the upper millimeter of regolith is mixed with great frequency and the rate of turnover drops off sharply at depth. Our work elaborates on this idea, addressing the sensitivity of this result to variations in parameters including meteoritic flux, impactor mass, velocity, angle of impact and crater geometry. In addition, we use these new methods and parameters to characterize the "mixing layer," as well as those less mixed layers below in an attempt to quantitatively match the new insights on spatial variation of the change in density with depth derived by the Diviner Lunar Radiometer.

  10. On the sputter alteration of regoliths of outer solar system bodies

    NASA Technical Reports Server (NTRS)

    Hapke, Bruce

    1987-01-01

    Several processes that are expected to occur when the porous regoliths of outer solar system bodies (without atmospheres) are subjected to energetic ion bombardment are discussed. The conclusions reached in much of the literature addressing sputtering are quantitatively or qualitatively incorrect because effects of soil porosity have been neglected. It is shown theoretically and experimentally that porosity reduces the effective sputtering yield of a soil by more than an order of magnitude. Between 90 and 97% of the sputtered atoms are trapped within the regolith, where they are factionated by differential desorption. Experiments indicate that more volatile species have higher desorption probabilities. This process is the most important way in which alteration of chemical and optical properties occurs when a regolith is sputtered. When a basic silicate soil is irradiated these effects lead to sputter-deposited films enriched in metallic iron, while O, Na and K are preferentially lost. The Na and K are present in the atmosphere above the sputtered silicate in quantities much greater than their abundances in the regolith. Icy regoliths of SO2 should be enriched in elemental S and/or S2O. This prediction is supported by the probable identification of S2O and polysulfur oxide bands in the IR spectra of H-sputtered SO2 reported by Moore. When porous mixtures of water, ammonia and methane frosts are sputtered, the loss of H and surface reactions of C, N and O in the deposits should produce complex hydrocarbons and carbohydrates, some of which may be quite dark. Such reactions may have played a role in the formation of the matrix material of carbonaceous chondrites prior to agglomeration.

  11. Radon Outgassing from the Surface of Mercury Evidenced by Its Low Th/U Ratio

    NASA Astrophysics Data System (ADS)

    Meslin, P.-Y.; Peplowski, P. N.; Deprez, G.

    2018-05-01

    The low, subchondritic Th/U ratio measured by MESSENGER can be explained by the release of radon from the Hermean regolith, and the corresponding exhalation rate is significantly larger than on the Moon, possibly indicating a thicker regolith.

  12. Lunar Regolith Simulant Materials: Recommendations for Standardization, Production, and Usage

    NASA Technical Reports Server (NTRS)

    Sibille, L.; Carpenter, P.; Schlagheck, R.; French, R. A.

    2006-01-01

    Experience gained during the Apollo program demonstrated the need for extensive testing of surface systems in relevant environments, including regolith materials similar to those encountered on the lunar surface. As NASA embarks on a return to the Moon, it is clear that the current lunar sample inventory is not only insufficient to support lunar surface technology and system development, but its scientific value is too great to be consumed by destructive studies. Every effort must be made to utilize standard simulant materials, which will allow developers to reduce the cost, development, and operational risks to surface systems. The Lunar Regolith Simulant Materials Workshop held in Huntsville, AL, on January 24 26, 2005, identified the need for widely accepted standard reference lunar simulant materials to perform research and development of technologies required for lunar operations. The workshop also established a need for a common, traceable, and repeatable process regarding the standardization, characterization, and distribution of lunar simulants. This document presents recommendations for the standardization, production and usage of lunar regolith simulant materials.

  13. The micrometeoroid complex and evolution of the lunar regolith

    NASA Technical Reports Server (NTRS)

    Horz, F.; Morrison, D. A.; Gault, D. E.; Oberbeck, V. R.; Quaide, W. L.; Vedder, J. F.; Brownlee, D. E.; Hartung, J. B.

    1977-01-01

    Monte Carlo-based computer calculations, as well as analytical approaches utilizing probabilistic arguments, were applied to gain insight into the principal regolith impact processes and their resulting kinetics. Craters 10 to 1500 m in diameter are largely responsible for the overall growth of the regolith. As a consequence the regolith has to be envisioned as a complex sequence of discrete ejecta blankets. Such blankets constitute first-order discontinuities in the evolving debris layer. The micrometeoroid complex then operates intensely on these fresh ejecta blankets and accomplishes only in an uppermost layer of approximately 1-mm thickness. The absolute flux of micrometeoroids based on lunar rock analyses averaged over the past few 10 to the 6th power years is approximately an order of magnitude lower than presentday satellite fluxes; however, there is indication that the flux increased in the past 10 to the 4th power years to become compatible with the satellite data. Furthermore, there is detailed evidence that the micrometeoroid complex existed throughout geologic time.

  14. Light scattering by lunar-like particle size distributions

    NASA Technical Reports Server (NTRS)

    Goguen, Jay D.

    1991-01-01

    A fundamental input to models of light scattering from planetary regoliths is the mean phase function of the regolith particles. Using the known size distribution for typical lunar soils, the mean phase function and mean linear polarization for a regolith volume element of spherical particles of any composition were calculated from Mie theory. The two contour plots given here summarize the changes in the mean phase function and linear polarization with changes in the real part of the complex index of refraction, n - ik, for k equals 0.01, the visible wavelength 0.55 micrometers, and the particle size distribution of the typical mature lunar soil 72141. A second figure is a similar index-phase surface, except with k equals 0.1. The index-phase surfaces from this survey are a first order description of scattering by lunar-like regoliths of spherical particles of arbitrary composition. They form the basis of functions that span a large range of parameter-space.

  15. Regolith stratigraphy at the Chang'E-3 landing site as seen by lunar penetrating radar

    NASA Astrophysics Data System (ADS)

    Fa, Wenzhe; Zhu, Meng-Hua; Liu, Tiantian; Plescia, Jeffrey B.

    2015-12-01

    The Chang'E-3 lunar penetrating radar (LPR) observations at 500 MHz reveal four major stratigraphic zones from the surface to a depth of ~20 m along the survey line: a layered reworked zone (<1 m), an ejecta layer (~2-6 m), a paleoregolith layer (~4-11 m), and the underlying mare basalts. The reworked zone has two to five distinct layers and consists of surface regolith. The paleoregolith buried by the ejecta from a 500 m crater is relatively homogenous and contains only a few rocks. Population of buried rocks increases with depth to ~2 m at first, and then decreases with depth, representing a balance between initial deposition of the ejecta and later turnover of the regolith. Combining with the surface age, the LPR observations indicate a mean accumulation rate of about 5-10 m/Gyr for the surface regolith, which is at least 4-8 times larger than previous estimation.

  16. Unique View of C Asteriod Regolith from the Jbilet Winselwan CM Chondrite

    NASA Technical Reports Server (NTRS)

    Zolensky, Michael; Mikouchi, Takashi; Hagiya, Kenji; Ohsumi, Kazumasa; Komatsu, Mutsumi; Chan, Queenie H. S.; Le, Loan; Kring, David; Cato, Michael; Fagan, Amy L.; hide

    2016-01-01

    C-class asteroids frequently exhibit reflectance spectra consistent with thermally metamor-phosed carbonaceous chondrites, or a mixture of phyllosilicate-rich material along with regions where they are absent. One particularly important example appears to be asteroid 162173 Ryugu, the target of the Hayabusa 2 mission, although most spectra of Ryugu are featureless, suggesting a heterogeneous regolith. Here we explore an alternative cause of dehydration of regolith of C-class asteroids impact shock melting. Impact shock melting has been proposed to explain some mineralogical characteristics of CB chondrites, but has rarely been considered a major process for hydrous carbonaceous chondrites. Jbilet Winselwan (JW) is a very fresh CM breccia from Morocco, with intriguing characteristics. While some lithologies are typical of CM2s, other clasts show evidence of brief, though significant impact brecciation and heating. The first evidence for this came from preliminary petrographic and stable isotope studies. We contend that highly-brecciated, partially-shocked, and dehydrated lithologies like those in JW dominate C-class asteroid regolith.

  17. Benefits of Mars ISRU Regolith Water Processing: A Case Study for the NASA Evolvable Mars Campaign

    NASA Technical Reports Server (NTRS)

    Kleinhenz, Julie; Paz, Aaron; Mueller, Robert

    2016-01-01

    ISRU of Mars resources was baselined in 2009 Design Reference Architecture (DRA) 5.0, but only for Oxygen production using atmospheric CO2. The Methane (LCH4) needed for ascent propulsion of the Mars Ascent Vehicle (MAV) would need to be brought from Earth. However: Extracting water from the Martian Regolith enables the production of both Oxygen and Methane from Mars resources: Water resources could also be used for other applications including: Life support, radiation shielding, plant growth, etc. Water extraction was not baselined in DRA5.0 due to perceived difficulties and complexity in processing regolith. The NASA Evolvable Mars Campaign (EMC) requested studies to look at the quantitative benefits and trades of using Mars water ISRUPhase 1: Examined architecture scenarios for regolith water retrieval. Completed October 2015. Phase 2: Deep dive of one architecture concept to look at end-to-end system size, mass, power of a LCH4/LO2 ISRU production system

  18. Lithification opf gas-rich chondrite regolith breccias by grain boundary and localized shock melting

    NASA Technical Reports Server (NTRS)

    Bischoff, A.; Rubin, A. E.; Keil, K.; Stoeffler, D.

    1983-01-01

    The fine-grained matrices (less than 150 microns) of 14 gas-rich ordinary chondrile regolith breccias were studied in an attempt to decipher the nature of the lithification process that converted loose regolith material into consolidated breccias. It is found that there is a continuouos gradation in matrix textures from nearly completely clastic (class A) to highly cemented (class C) breccias in which the remining clasts are completely surrounded by interstitial, shock-melted material. It is concluded that this interstitial material is formed by shock melting in the porous regolith. In general, the abundances of solar-wind-implanted He-4 and Ne-20 are inversely correlated with the abundance of intenstitial, shock-melted, feldspathic material. Chondrites with the highest abundance of interstitial, melted material (class C) experienced the highest shock pressures and temperatures and suffered the most extensive degassing. It is this interstitial, feldspathic melt that lithifies and cements the breccias together; those breccias with very little interstitial melt (class A) are the most porous and least consolidated.

  19. Apollo 14 regolith breccias - Different glass populations and their potential for charting space time variations

    NASA Technical Reports Server (NTRS)

    Delano, John W.

    1988-01-01

    Apollo 14 regolith breccias (14313, 14307, 14301, 14049, 14047) have been found to have different populations of nonagglutinitic, mare-derived glasses. These variations appear to not only reflect different source regoliths but also different closure ages for these breccias. Based upon these different glass populations, 14301 is inferred to have a closure age sometime during the epoch of mare volcanism. All of the other four breccias were formed after the termination of mare volcanism with a possible age sequence from old to young of the following: 14307, 14313, 14049, 14047. Due to the relative simplicity of acquiring high-quality chemical data on large numbers of glasses by electron microprobe, mare glass populations allow: (1) classification of regolith breccias with respect to provenance and (2) estimation of their relative and absolute closure ages. The determination of (Ar-40)-(Ar-39) ages on individual glass spherules within breccias using the laser probe should in the future prove to be a promising extension of the present study.

  20. Integrated geophysical study to understand the architecture of the deep critical zone in the Luquillo Critical Zone Observatory (Puerto Rico

    NASA Astrophysics Data System (ADS)

    Comas, X.; Wright, W. J.; Hynek, S. A.; Ntarlagiannis, D.; Terry, N.; Whiting, F.; Job, M. J.; Brantley, S. L.; Fletcher, R. C.

    2016-12-01

    The Luquillo Critical Zone Observatory (CZO) in Puerto Rico is characterized by a complex system of heterogeneous fractures that participate in the formation of corestones, and influence the development of a regolith by the alteration of the bedrock at very rapid weathering rates. The spatial distribution of fractures, and its influence on regolith thickness is, however, currently not well understood. In this study, we used an array of near-surface geophysical methods, including ground penetrating radar, terrain conductivity, electrical resistivity imaging and induced polarization, OhmMapper, and shallow seismic, constrained with direct methods from previous studies. These methods were combined with stress modeling to better understand: 1) changes in regolith thickness; and 2) variation of the spatial distribution and density of fractures with topography and proximity to the knickpoint. Our observations show the potential of geophysical methods for imaging variability in regolith thickness, and agree with the result of a stress model showing increased dilation of fractures with proximity to the knickpoint.

  1. RASSOR - Regolith Advanced Surface Systems Operations Robot

    NASA Technical Reports Server (NTRS)

    Gill, Tracy R.; Mueller, Rob

    2015-01-01

    The Regolith Advanced Surface Systems Operations Robot (RASSOR) is a lightweight excavator for mining in reduced gravity. RASSOR addresses the need for a lightweight (<100 kg) robot that is able to overcome excavation reaction forces while operating in reduced gravity environments such as the moon or Mars. A nominal mission would send RASSOR to the moon to operate for five years delivering regolith feedstock to a separate chemical plant, which extracts oxygen from the regolith using H2 reduction methods. RASSOR would make 35 trips of 20 kg loads every 24 hours. With four RASSORs operating at one time, the mission would achieve 10 tonnes of oxygen per year (8 t for rocket propellant and 2 t for life support). Accessing craters in space environments may be extremely hard and harsh due to volatile resources - survival is challenging. New technologies and methods are required. RASSOR is a product of KSC Swamp Works which establishes rapid, innovative and cost effective exploration mission solutions by leveraging partnerships across NASA, industry and academia.

  2. Improved Regolith-Landform and Geological Mapping using AIRSAR Data as an Aid to Mineral Exploration in the North-Eastern Goldfields Region, Western Australia

    NASA Technical Reports Server (NTRS)

    Tapley, Ian J.

    1996-01-01

    The distinctive contribution of AIRSAR data in characterizing the regolith-landforms in a relatively vegetation free environment are discussed. AIRSAR frame processed data were initially MAF-cleaned to enhance the signal content of the data before geocoding to AMG coordinates. Colors in a three frequency single polarization combination image C-, L- P- bands, and in an enhancement of pedestal height, relate directly to the scale of surface roughness of the various regolith units Examination of the AIRSAR enhancements reveals that in mafic terrain, and to a lesser extent, in felsic terrain, AIRSAR data provides discrimination between the principle geomorphic regimes, relict, erosional and depositional. A multivariate statistical technique called an all-possible subsets calculation was used to examine the degree of polarimetric separation between selected regolith-landforms for all combinations of the nine band AIRSAR radar. An unanticipated aspect of the research was the identification on the AIRSAR imagery of previously unmapped structural features.

  3. Modeling Regolith Temperatures and Volatile Ice Processes (Invited)

    NASA Astrophysics Data System (ADS)

    Mellon, M. T.

    2013-12-01

    Surface and subsurface temperatures are an important tool for exploring the distribution and dynamics of volatile ices on and within planetary regoliths. I will review thermal-analysis approaches and recent applications in the studies of volatile ice processes. Numerical models of regolith temperatures allow us to examine the response of ices to periodic and secular changes in heat sources such as insolation. Used in conjunction with spatially and temporally distributed remotely-sensed temperatures, numerical models can: 1) constrain the stability and dynamics of volatile ices; 2) define the partitioning between phases of ice, gas, liquid, and adsorbate; and 3) in some instances be used to probe the distribution of ice hidden from view beneath the surface. The vapor pressure of volatile ices (such as water, carbon dioxide, and methane) depends exponentially on temperature. Small changes in temperature can result in transitions between stable phases. Cyclic temperatures and the propagation of thermal waves into the subsurface can produce a strong hysteresis in the population and partitioning of various phases (such as between ice, vapor, and adsorbate) and result in bulk transport. Condensation of ice will also have a pronounced effect on the thermal properties of otherwise loose particulate regolith. Cementing grains at their contacts through ice deposition will increase the thermal conductivity, and may enhance the stability of additional ice. Likewise sintering of grains within a predominantly icy regolith will increase the thermal conductivity. Subsurface layers that result from ice redistribution can be discriminated by remote sensing when combined with numerical modeling. Applications of these techniques include modeling of seasonal carbon dioxide frosts on Mars, predicting and interpreting the subsurface ice distribution on Mars and in Antarctica, and estimating the current depth of ice-rich permafrost on Mars. Additionally, understanding cold trapping ices in regions of the regolith of airless bodies, such as Mercury and the Moon, are aided by numerical modeling of regolith temperatures. Thermally driven sublimation of volatiles (water ice on Mars and more exotic species on icy moons in the outer solar system) can result in terrain degradation and collapse.

  4. Regolith properties under trees and the biomechanical effects caused by tree root systems as recognized by electrical resistivity tomography (ERT)

    NASA Astrophysics Data System (ADS)

    Pawlik, Łukasz; Kasprzak, Marek

    2018-01-01

    Following previous findings regarding the influence of vascular plants (mainly trees) on weathering, soil production and hillslope stability, in this study, we attempted to test a hypothesis regarding significant impacts of tree root systems on soil and regolith properties. Different types of impacts from tree root system (direct and indirect) are commonly gathered under the key term of "biomechanical effects". To add to the discussion of the biomechanical effects of trees, we used a non-invasive geophysical method, electrical resistivity tomography (ERT), to investigate the profiles of four different configurations at three study sites within the Polish section of the Outer Western Carpathians. At each site, one long profile (up to 189 m) of a large section of a hillslope and three short profiles (up to 19.5 m), that is, microsites occupied by trees or their remnants, were made. Short profiles included the tree root zone of a healthy large tree, the tree stump of a decaying tree and the pit-and-mound topography formed after a tree uprooting. The resistivity of regolith and bedrock presented on the long profiles and in comparison with the short profiles through the microsites it can be seen how tree roots impact soil and regolith properties and add to the complexity of the whole soil/regolith profile. Trees change soil and regolith properties directly through root channels and moisture migration and indirectly through the uprooting of trees and the formation of pit-and-mound topography. Within tree stump microsites, the impact of tree root systems, evaluated by a resistivity model, was smaller compared to microsites with living trees or those with pit-and-mound topography but was still visible even several decades after the trees were windbroken or cut down. The ERT method is highly useful for quick evaluation of the impact of tree root systems on soils and regolith. This method, in contrast to traditional soil analyses, offers a continuous dataset for the entire microsite and at depths not normally reached by standard soil excavations. The non-invasive nature of ERT studies is especially important for protected areas as it was shown in the present study.

  5. Some things we can infer about the Moon from the Composition of the Apollo 16 Regolith

    NASA Technical Reports Server (NTRS)

    Korotev, Randy L.

    1997-01-01

    Characteristics of the regolith of Cayley plains as sampled at the Apollo 16 lunar landing site are reviewed and new compositional data are presented for samples of less than 1 mm fines ('soils') and 1-2 mm regolith particles. As a means of determining which of the many primary (igneous) and secondary (crystalline breccias) lithologic components that have been identified in the soil are volumetrically important and providing an estimate of their relative abundances, more than 3 x 10(exp 6) combinations of components representing nearly every lithology that has been observed in the Apollo 16 regolith were systematically tested to determine which combinations best account for the composition of the soils. Conclusions drawn from the modeling include the following. At the site, mature soil from the Cayley plains consists of 64.5% +/- 2.7% components representing 'prebasin' materials: anorthosites, feldspathic breccias, and a small amount (2.6% +/- 1.5% of total soil) of nonmare, mafic plutonic rocks, mostly gabbronorites. On average, these components are highly feldspathic, with average concentrations of 3l-32% Al2O3 and 2-3% FeO and a molar Mg/(Mg+Fe) ratio of O.68. The remaining 36% of the regolith is syn- and postbasin material: 28.8% +/- 2.4% mafic impact-melt breccias (MIMBS, i.e., 'LKFM' and 'VHA basalts') created at the time of basin formation, 6.0% +/- 1.4% mare-derived material (impact and volcanic glass, crystalline basalt) with an average TiO2 concentration of 2.4%, and 1% postbasin meteoritic material. The MIMBs are the principal (80-90%) carrier of incompatible trace elements (rare earths, Th, etc.) and the carrier of about one-half of the siderophile elements and elements associated with mafic mineral phases (Fe, Mg, Mn, Cr, Sc). Most (71 %) of the Fe in the present regolith derives from syn- and postbasin sources (MIMBS, mare-derived material, and meteorites). Thus, although the bulk composition of the Apollo 16 regolith is nominally that of noritic anorthosite, the noritic part (the MIMBs) and anorthositic parts (the prebasin components) are largely unrelated.

  6. The properties of the lunar regolith at Chang'e-3 landing site: A study based on LPR data

    NASA Astrophysics Data System (ADS)

    Feng, J.; Su, Y.; Xing, S.; Ding, C.; Li, C.

    2015-12-01

    In situ sampling from surface is difficult in the exploration of planets and sometimes radar sensing is a better choice. The properties of the surface material such as permittivity, density and depth can be obtained by a surface penetrating radar. The Chang'e-3 (CE-3) landed in the northern Mare Imbrium and a Lunar Penetrating Radar (LPR) is carried on the Yutu rover to detect the shallow structure of the lunar crust and the properties of the lunar regolith, which will give us a close look at the lunar subsurface. We process the radar data in a way which consist two steps: the regular preprocessing step and migration step. The preprocessing part includes zero time correction, de-wow, gain compensation, DC removal, geometric positioning. Then we combine all radar data obtained at the time the rover was moving, and use FIR filter to reduce the noise in the radar image with a pass band frequency range 200MHz-600MHz. A normal radar image is obtained after the preprocessing step. Using a nonlinear least squares fitting method, we fit the most hyperbolas in the radar image which are caused by the buried objects or rocks in the regolith and estimate the EM wave propagation velocity and the permittivity of the regolith. For there is a fixed mathematical relationship between dielectric constant and density, the density profile of the lunar regolith is also calculated. It seems that the permittivity and density at the landing site is larger than we thought before. Finally with a model of variable velocities, we apply the Kirchhoff migration method widely used in the seismology to transform the the unfocused space-time LPR image to a focused one showing the object's (most are stones) true location and size. From the migrated image, we find that the regolith depth in the landing site is smaller than previous study and the stone content rises rapidly with depth. Our study suggests that the landing site is a young region and the reworked history of the surface is short, which is consistent with crater density, showing the gradual formation of regolith by rock fracture during impact events.

  7. Obliquity variation in a Mars climate evolution model

    NASA Technical Reports Server (NTRS)

    Tyler, D.; Haberle, Robert M.

    1993-01-01

    The existence of layered terrain in both polar regions of Mars is strong evidence supporting a cyclic variation in climate. It has been suggested that periods of net deposition have alternated with periods of net erosion in creating the layered structure that is seen today. The cause for this cyclic climatic behavior is variation in the annually averaged latitudinal distribution of solar insolation in response to obliquity cycles. For Mars, obliquity variation leads to major climatological excursion due to the condensation and sublimation of the major atmospheric constituent, CO2. The atmosphere will collapse into the polar caps, or existing caps will rapidly sublimate into the atmosphere, dependent upon the polar surface heat balance and the direction of the change in obliquity. It has been argued that variations in the obliquity of Mars cause substantial departures from the current climatological values of the surface pressure and the amount of CO2 stored in both the planetary regolith and polar caps. In this new work we have modified the Haberle et al. model to incorporate variable obliquity by allowing the polar and equatorial insolation to become functions of obliquity, which we assume to vary sinusoidally in time. As obliquity varies in the model, there can be discontinuities in the time evolution of the model equilibrium values for surface pressure, regolith, and polar cap storage. The time constant, tau r, for the regolith to find equilibrium with the climate is estimated--depending on the depth, thermal conductivity, and porosity of the regolith--between 10(exp 4) and 10(exp 6) yr. Thus, using 2000-yr timesteps to move smoothly through the 0.1250 m.y. obliquity cycles, we have an atmosphere/regolith system that cannot be assumed in equilibrium. We have dealt with this problem by limiting the rate at which CO2, can move between the atmosphere and regolith, mimicking the diffusive nature and effects of the temperature and pressure waves, by setting the time rate of change of regolith storage proportional to the difference between equilibrium storage and current storage.

  8. Young Lunar Volcanic Features: How Did They Form?

    NASA Astrophysics Data System (ADS)

    Elder, Catherine; Hayne, Paul O.; Donaldson Hanna, Kerri; Bandfield, Joshua; Ghent, Rebecca; Williams, Jean-Pierre; Paige, David A.

    2016-10-01

    Irregular mare patches (IMPs) on the Moon are younger than 100 Myr [1, 2], but their formation mechanism is unknown. Previous work has suggested caldera collapse [3], explosive outgassing [2], pyroclastic eruptions [4], basaltic lava flows [1, 5], and regolith drainage into graben [6]. Here we present observations from the Lunar Reconnaissance Orbiter (LRO) Diviner thermal radiometer of the four largest IMPs. These observations suggest that the surfaces of the IMPs are on average only slightly rockier than the surrounding regolith. The nighttime cooling curves of the IMPs and the surrounding regolith do not intersect, which suggests that there is no layering in the top 5-10 cm of the IMPs. We also measure the thermal inertia (parameterized through the "H-parameter" [7]) of the IMPs. We find that the thermal inertia of Sosigenes is higher than that of the surrounding regolith (probably due to mass wasting), the thermal inertia of Cauchy-5 and Maskelyne is not significantly different from the surrounding regolith, and the thermal inertia of the largest smooth mound in Ina is significantly lower than the surrounding regolith. Only some IMPs are in topographic depressions or associated with graben, so neither caldera collapse nor drainage into graben can explain the formation of all IMPs. It is unlikely that basaltic lava flows would lead to a thermal inertia lower than that of lunar regolith. Therefore, of the formation mechanisms proposed to date, pyroclastic eruptions or another type of explosive outgassing [e.g. 2] possibly accompanied by basaltic lava flows or drainage into graben best explain the available observations of IMPs.[1] Braden, S. et al. (2014) Nature Geo 7, 787-791. [2] Schultz, P. H. et al. (2006) Nature 444, 184-186. [3] El-Baz, F. (1973) Apollo 17: Preliminary Science Report 330, 30-13. [4] Carter, L. B. et al. (2013) LPSC 44, 2146. [5] Garry, W. B. et al. (2012) JGR 117, E00H31. [6] Qiao, L. et al. (2002) LPSC 47, 2002. [7] Vasavada, A. R. et al. (2012) JGR 117, E00H18.Part of this work was performed at the Jet Propulsion Laboratory, California Institute of Technology under contract with the National Aeronautics and Space Administration.

  9. Performance of Regolith Feed Systems for Analog Field Tests of In-Situ Resource Utilization Oxygen Production Plants in Mauna Kea, Hawaii

    NASA Technical Reports Server (NTRS)

    Townsend, Ivan I.; Mueller, Robert P.; Mantovani, James G.; Zacny, Kris A.; Craft, Jack

    2010-01-01

    This paper focuses on practical aspects of mechanical auger and pneumatic regolith conveying system feeding In-Situ Resource Utilization Oxygen production plants. The subsystems of these feedstock delivery systems include an enclosed auger device, pneumatic venturi educator, jet-lift regolith transfer, innovative electro-cyclone gas-particle separation/filtration systems, and compressors capable of dealing with hot hydrogen and/or methane gas re-circulating in the system. Lessons learned from terrestrial laboratory, reduced gravity and field testing on Mauna Kea Volcano in Hawaii during NASA lunar analog field tests will be discussed and practical design tips will be presented.

  10. The Nature of C Asteroid Regolith Revealed from the Jbilet Winselwan CM Chondrite

    NASA Technical Reports Server (NTRS)

    Zolensky, Michael; Mikouchi, Takashi; Hagiya, Kenji; Ohsumi, Kazumasa; Komatsu, Mutsumi; Chan, Queenie H. S.; Le, Loan; Kring, David; Cato, Michael; Fagan, Amy L.

    2016-01-01

    C-class asteroids frequently exhibit reflectance spectra consistent with thermally metamorphosed carbonaceous chondrites, or a mixture of phyllosilicate-rich material along with regions where they are absent. One particularly important example appears to be asteroid 162173 Ryugu, the target of the Hayabusa 2 mission, although most spectra of Ryugu are featureless, suggesting a heterogeneous regolith. Here we explore an alternative cause of dehydration of regolith of C-class asteroids - impact shock melting. Impact shock melting has been proposed to ex-plain some mineralogical characteristics of CB chondrites, but has rarely been considered a major process for hydrous carbonaceous chondrites.

  11. Lunar Oxygen Production and Metals Extraction Using Ionic Liquids

    NASA Technical Reports Server (NTRS)

    Marone, Matthew; Paley, Mark Steven; Donovan, David N.; Karr, Laurel J.

    2009-01-01

    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.

  12. Optical Extinction Measurements of Dust Density in the GMRO Regolith Test Bin

    NASA Technical Reports Server (NTRS)

    Lane, J.; Mantovani, J.; Mueller, R.; Nugent, M.; Nick, A.; Schuler, J.; Townsend, I.

    2016-01-01

    A regolith simulant test bin was constructed and completed in the Granular Mechanics and Regolith Operations (GMRO) Lab in 2013. This Planetary Regolith Test Bed (PRTB) is a 64 sq m x 1 m deep test bin, is housed in a climate-controlled facility, and contains 120 MT of lunar-regolith simulant, called Black Point-1 or BP-1, from Black Point, AZ. One of the current uses of the test bin is to study the effects of difficult lighting and dust conditions on Telerobotic Perception Systems to better assess and refine regolith operations for asteroid, Mars and polar lunar missions. Low illumination and low angle of incidence lighting pose significant problems to computer vision and human perception. Levitated dust on Asteroids interferes with imaging and degrades depth perception. Dust Storms on Mars pose a significant problem. Due to these factors, the likely performance of telerobotics is poorly understood for future missions. Current space telerobotic systems are only operated in bright lighting and dust-free conditions. This technology development testing will identify: (1) the impact of degraded lighting and environmental dust on computer vision and operator perception, (2) potential methods and procedures for mitigating these impacts, (3) requirements for telerobotic perception systems for asteroid capture, Mars dust storms and lunar regolith ISRU missions. In order to solve some of the Telerobotic Perception system problems, a plume erosion sensor (PES) was developed in the Lunar Regolith Simulant Bin (LRSB), containing 2 MT of JSC-1a lunar simulant. PES is simply a laser and digital camera with a white target. Two modes of operation have been investigated: (1) single laser spot - the brightness of the spot is dependent on the optical extinction due to dust and is thus an indirect measure of particle number density, and (2) side-scatter - the camera images the laser from the side, showing beam entrance into the dust cloud and the boundary between dust and void. Both methods must assume a mean particle size in order to extract a number density. The optical extinction measurement yields the product of the 2nd moment of the particle size distribution and the extinction efficiency Qe. For particle sizes in the range of interest (greater than 1 micrometer), Qe approximately equal to 2. Scaling up of the PES single laser and camera system is underway in the PRTB, where an array of lasers penetrate a con-trolled dust cloud, illuminating multiple targets. Using high speed HD GoPro video cameras, the evolution of the dust cloud and particle size density can be studied in detail.

  13. High energy electron sintering of icy regoliths: Formation of the PacMan thermal anomalies on the icy Saturnian moons

    NASA Astrophysics Data System (ADS)

    Schaible, M. J.; Johnson, R. E.; Zhigilei, L. V.; Piqueux, S.

    2017-03-01

    The so-called 'PacMan' features on the leading hemispheres of the icy Saturnian moons of Mimas, Tethys and Dione were initially identified as anomalous optical discolorations and subsequently shown to have greater thermal inertia than the surrounding regions. The shape of these regions matches calculated deposition contours of high energy plasma electrons moving opposite to the moon's orbital direction, thus suggesting that electron interactions with the grains produce the observed anomalies. Here, descriptions of radiation-induced diffusion processes are given, and various sintering models are considered to calculate the rate of increase in the contact volume between grains in an icy regolith. Estimates of the characteristic sintering timescale, i.e. the time necessary for the thermal inertia to increase from that measured outside the anomalous regions to that within, are given for each of the moons. Since interplanetary dust particle (IDP) impact gardening and E-ring grain infall would be expected to mix the regolith and obscure the effects of high energy electrons, sintering rates are compared to rough estimates of the impact-induced resurfacing rates. Estimates of the sintering timescale determined by extrapolating laboratory measurements are below ∼0.03 Myr, while the regolith renewal timescales are larger than ∼0.1 Myr, thus indicating that irradiation by the high energy electrons should be sufficient to form stable thermal anomalies. More detailed models developed for sintering of spherical grains are able to account for the radiation-induced anomalies on Mimas and Tethys only if the regoliths on those bodies are relatively compact and composed of small (≲ 5 μm) grains or grain aggregates, and/or the grains are highly non-spherical with surface defect densities in the inter-grain contact regions that are much higher than expected for crystalline water ice grains at thermal equilibrium. These results are consistent with regolith thermal conductivity models which can only be reconciled with spacecraft observations if the contacts between grains are assumed to have much lower thermal conductance than predicted for idealized grains. The strength of the anomalies on Tethys and Dione appear to be limited by E-ring grain infall, while on Mimas IDP gardening limits the strength of the anomaly. The smaller flux of more deeply penetrating high energy (>1 MeV) electrons on Dione can account for the small thermal inertia differences measured there. Determining regolith sintering rates and the corresponding effect on thermal conductivity can, in principle, provide an independent constraint on the regolith grain geometries and exposure timescales for icy bodies.

  14. Three-Dimensional (3D) Additive Construction: Printing with Regolith

    NASA Technical Reports Server (NTRS)

    Tsoras, Alexandra

    2013-01-01

    Three dimensional (3D) printing is a new and booming topic in many realms of research and engineering technology. When it comes to space science and aerospace engineering, it can be useful in numerous ways. As humans travel deeper into space and farther from Earth, sending large quantities of needed supplies from Earth for a mission becomes astronomically expensive and less plausible. In order to reach further to new places, In Situ Resource Utilization (ISRU), a project that pushes for technologies to use materials already present in the destination's environment, is necessary. By using materials already available in space such as regolith from the Moon, Mars, or an asteroid's surface, fewer materials need to be brought into space on a launched vehicle. This allows a vehicle to be filled with more necessary supplies for a deep space mission that may not be found in space, like food and fuel. This project's main objective was to develop a 3D printer that uses regolith to "print" large structures, such as a dome, to be used as a heat shield upon a vehicle's reentry into the atmosphere or even a habitat. 3D printing is a growing technology that uses many different methods to mix, heat, and mold a material into a specific shape. In order to heat the regolith enough to stick together into a solid shape, it must be sintered at each layer of material that is laid. Sintering is a process that heats and compresses a powdered material until it fuses into a solid, which requires a lot of energy input. As an alternative, a polymer can be mixed with the regolith before or as it is sent to the 3D printer head to be placed in the specific shape. The addition of the polymer, which melts and binds at much lower temperatures than sintering temperatures, greatly decreases the required heating temperature and energy input. The main task of the project was to identify a functional material for the printer. The first step was to find a miscible. polymer/solvent solution. This solution was added to the regolith and the solvent was evaporated essentially leaving polymer-coated regolith particles. This material would be sent through the printer head and heated layer by layer to melt the polymer and bind the regolith. This method was one of many in a large goal to utilize materials in space with a custom-made 3D printer that builds dome-shaped habitats and other essential equipment for future deep space missions.

  15. Experimental Investigation of InSight HP3 Mole Interaction with Martian Regolith Simulant. Quasi-Static and Dynamic Penetration Testing

    NASA Astrophysics Data System (ADS)

    Marshall, Jason P.; Hudson, Troy L.; Andrade, José E.

    2017-10-01

    The InSight mission launches in 2018 to characterize several geophysical quantities on Mars, including the heat flow from the planetary interior. This quantity will be calculated by utilizing measurements of the thermal conductivity and the thermal gradient down to 5 meters below the Martian surface. One of the components of InSight is the Mole, which hammers into the Martian regolith to facilitate these thermal property measurements. In this paper, we experimentally investigated the effect of the Mole's penetrating action on regolith compaction and mechanical properties. Quasi-static and dynamic experiments were run with a 2D model of the 3D cylindrical mole. Force resistance data was captured with load cells. Deformation information was captured in images and analyzed using Digitial Image Correlation (DIC). Additionally, we used existing approximations of Martian regolith thermal conductivity to estimate the change in the surrounding granular material's thermal conductivity due to the Mole's penetration. We found that the Mole has the potential to cause a high degree of densification, especially if the initial granular material is relatively loose. The effect on the thermal conductivity from this densification was found to be relatively small in first-order calculations though more complete thermal models incorporating this densification should be a subject of further investigation. The results obtained provide an initial estimate of the Mole's impact on Martian regolith thermal properties.

  16. Requirements and Techniques for Developing and Measuring Simulant Materials

    NASA Technical Reports Server (NTRS)

    Rickman, Doug; Owens, Charles; Howard, Rick

    2006-01-01

    The 1989 workshop report entitled Workshop on Production and Uses of Simulated Lunar Materials and the Lunar Regolith Simulant Materials: Recommendations for Standardization, Production, and Usage, NASA Technical Publication identify and reinforced a need for a set of standards and requirements for the production and usage of the lunar simulant materials. As NASA need prepares to return to the moon, a set of requirements have been developed for simulant materials and methods to produce and measure those simulants have been defined. Addressed in the requirements document are: 1) a method for evaluating the quality of any simulant of a regolith, 2) the minimum Characteristics for simulants of lunar regolith, and 3) a method to produce lunar regolith simulants needed for NASA's exploration mission. A method to evaluate new and current simulants has also been rigorously defined through the mathematics of Figures of Merit (FoM), a concept new to simulant development. A single FoM is conceptually an algorithm defining a single characteristic of a simulant and provides a clear comparison of that characteristic for both the simulant and a reference material. Included as an intrinsic part of the algorithm is a minimum acceptable performance for the characteristic of interest. The algorithms for the FoM for Standard Lunar Regolith Simulants are also explicitly keyed to a recommended method to make lunar simulants.

  17. A Thorium-rich Mare Basalt Rock Fragment from the Apollo 12 Regolith: A Sample from a Young Procellarum Flow?

    NASA Technical Reports Server (NTRS)

    Jolliff, B. L.; Zeigler, R. A.; Korotev, R. L.; Barra, F.; Swindle, T. D.

    2005-01-01

    In this abstract, we report on the composition, mineralogy and petrography of a basaltic rock fragment, 12032,366-18, found in the Apollo 12 regolith. Age data, collected as part of an investigation by Barra et al., will be presented in detail in. Here, only the age dating result is summarized. This rock fragment garnered our attention because it is significantly enriched in incompatible elements, e.g., 7 ppm thorium, compared to other known lunar basalts. Its mineral- and trace-element chemistry set it apart from other Apollo 12 basalts and indeed from all Apollo and Luna basalts. What makes it potentially very significant is the possibility that it is a sample of a relatively young, thorium-rich basalt flow similar to those inferred to occur in the Procellarum region, especially northwestern Procellarum, on the basis of Lunar Prospector orbital data. Exploiting the lunar regolith for the diversity of rock types that have been delivered to a landing site by impact processes and correlating them to their likely site of origin using remote sensing will be an important part of future missions to the Moon. One such mission is Moonrise, which would collect regolith samples from the South Pole-Aitken Basin, concentrating thousands of rock fragments of 3-20 mm size from the regolith, and returning the samples to Earth.

  18. Dust Interactions on Small Solar System Bodies and Technology Considerations for Exploration

    NASA Technical Reports Server (NTRS)

    Kobrick, Ryan,; Hoffman, Jeffrey; Pavone, Marco; Street, Kenneth; Rickman, Douglas

    2014-01-01

    Small-bodies such as asteroids and Mars' moons Phobos and Deimos have relatively unknown regolith environments. It is hypothesized that dust preserved in the regolith on the surfaces will have similar mechanical properties to lunar dust because of similar formation processes from micrometeorite bombardment, low relative gravity for slow settling times, and virtually no weathering because there is no atmosphere. This combination of processes infers that small-body dust particles will be highly angular and retain abrasive properties. The focus of this paper uses the mission architecture and engineering design for an asteroid hopper known as Hedgehog, a spherical spacecraft with several symmetric spikes used to aid with tumbling mobility in a low gravity environment. Dust abrasion considerations are highlighted throughout the paper relating to the lead authors' previous work, but act as an example of one of many important dust or regolith physical properties that need to be considered for future exploration. Measurable regolith properties are summarized in order to identify technologies that may be useful for exploration in terms of scientific return and spacecraft design. Previous instruments are summarized in this paper that could be used on the Hedgehog. Opportunities for hardware payloads are highlighted that include low mass solutions or dualpurpose instruments that can measure regolith or dust properties. Finally, dust mitigation suggestions are made for vehicles of this mobility profile.

  19. The Thermal Electrical Conductivity Probe (TECP) for Phoenix

    NASA Technical Reports Server (NTRS)

    Zent, Aaron P.; Hecht, Michael H.; Cobos, Doug R.; Campbell, Gaylon S.; Campbell, Colin S.; Cardell, Greg; Foote, Marc C.; Wood, Stephen E.; Mehta, Manish

    2009-01-01

    The Thermal and Electrical Conductivity Probe (TECP) is a component of the Microscopy, Electrochemistry, and Conductivity Analyzer (MECA) payload on the Phoenix Lander. TECP will measure the temperature, thermal conductivity and volumetric heat capacity of the regolith. It will also detect and quantify the population of mobile H2O molecules in the regolith, if any, throughout the polar summer, by measuring the electrical conductivity of the regolith, as well as the dielectric permittivity. In the vapor phase, TECP is capable of measuring the atmospheric H2O vapor abundance, as well as augment the wind velocity measurements from the meteorology instrumentation. TECP is mounted near the end of the 2.3 m Robotic Arm, and can be placed either in the regolith material or held aloft in the atmosphere. This paper describes the development and calibration of the TECP. In addition, substantial characterization of the instrument has been conducted to identify behavioral characteristics that might affect landed surface operations. The greatest potential issue identified in characterization tests is the extraordinary sensitivity of the TECP to placement. Small gaps alter the contact between the TECP and regolith, complicating data interpretation. Testing with the Phoenix Robotic Arm identified mitigation techniques that will be implemented during flight. A flight model of the instrument was also field tested in the Antarctic Dry Valleys during the 2007-2008 International Polar year. 2

  20. Series-Bosch Technology for Oxygen Recovery During Lunar or Martian Surface Missions

    NASA Technical Reports Server (NTRS)

    Abney, Morgan B.; Mansell, J. Matthew; Rabenberg, Ellen; Stanley, Christine M.; Edmunson, Jennifer; Alleman, James E.; Chen, Kevin; Dumez, Sam

    2014-01-01

    Long-duration surface missions to the Moon or Mars will require life support systems that maximize resource recovery to minimize resupply from Earth. To address this need, NASA previously proposed a Series-Bosch (S-Bosch) oxygen recovery system, based on the Bosch process, which can theoretically recover 100% of the oxygen from metabolic carbon dioxide. Bosch processes have the added benefits of the potential to recover oxygen from atmospheric carbon dioxide and the use of regolith materials as catalysts, thereby eliminating the need for catalyst resupply from Earth. In 2012, NASA completed an initial design for an S-Bosch development test stand that incorporates two catalytic reactors in series including a Reverse Water-Gas Shift (RWGS) Reactor and a Carbon Formation Reactor (CFR). In 2013, fabrication of system components, with the exception of a CFR, and assembly of the test stand was initiated. Stand-alone testing of the RWGS reactor was completed to compare performance with design models. Continued testing of Lunar and Martian regolith simulants provided sufficient data to design a CFR intended to utilize these materials as catalysts. Finally, a study was conducted to explore the possibility of producing bricks from spent regolith catalysts. The results of initial demonstration testing of the RWGS reactor, results of continued catalyst performance testing of regolith simulants, and results of brick material properties testing are reported. Additionally, design considerations for a regolith-based CFR are discussed.

  1. Series-Bosch Technology for Oxygen Recovery During Lunar or Martian Surface Missions

    NASA Technical Reports Server (NTRS)

    Abney, Morgan B.; Mansell, James M.; Stanley, Christine; Edmunson, Jennifer; Dumez, Samuel; Chen, Kevin; Alleman, James E.

    2014-01-01

    Long-duration surface missions to the Moon or Mars will require life support systems that maximize resource recovery to minimize resupply from Earth. To address this need, NASA previously proposed a Series-Bosch (S-Bosch) oxygen recovery system, based on the Bosch process, which can theoretically recover 100% of the oxygen from metabolic carbon dioxide. Bosch processes have the added benefits of the potential to recover oxygen from atmospheric carbon dioxide and the use of regolith materials as catalysts, thereby eliminating the need for catalyst resupply from Earth. In 2012, NASA completed an initial design for an S-Bosch development test stand that incorporates two catalytic reactors in series including a Reverse Water-Gas Shift (RWGS) Reactor and a Carbon Formation Reactor (CFR). In 2013, fabrication of system components, with the exception of a CFR, and assembly of the test stand was initiated. Stand-alone testing of the RWGS reactor was completed to compare performance with design models. Continued testing of Lunar and Martian regolith simulants provided sufficient data to design a CFR intended to utilize these materials as catalysts. Finally, a study was conducted to explore the possibility of producing bricks from spend regolith catalysts. The results of initial demonstration testing of the RWGS reactor, results of continued catalyst performance testing of regolith simulants, and results of brick material properties testing are reported. Additionally, design considerations for a regolith-based CFR are discussed.

  2. Internship Tasks Associated With CIF Icy Regolith Excavation and Volatile Capture Under Vacuum Conditions

    NASA Technical Reports Server (NTRS)

    Ballesteros, Erik Nicholas

    2014-01-01

    Understanding the surface and atmosphere of Mars is critical to current and future development of exploration systems. Dealing with the Martian regolith-the top layer of soil-remains a significant challenge, and much research is still needed. Addressing this need, the Cryogenics Test Lab and Granular Mechanics and Regolith Operations Lab at NASA's Kennedy Space Center are partnering to develop an apparatus that utilizes simulated Martian regolith in an analogous atmospheric environment to gather data about how the material behaves when exposed to water vapor. Martian surface temperatures range from 128 K (-145 C) to 308 K (35 C), and the average pressure is approximately 4.5 Torr; which presents an environment where water can potentially exist in vapor, solid or liquid form. And based on prior Mars missions such as the Phoenix Lander, it is known that water-ice exists just below the surface. This test apparatus will attempt to recreate the conditions that contributed to the Martian ice deposits by exposing a sample to water vapor at low pressure and temperature; thereby forming ice inside the simulant via diffusion. From this, we can better understand the properties and behavior of the regolith, and have more knowledge concerning its ability to store water-and subsequently, how to dig up and extract that water-which will be crucial to sample gathering when the first manned Mars mission takes place.

  3. The distribution of Martian ground ice at other epochs

    NASA Technical Reports Server (NTRS)

    Mellon, M. T.; Jakosky, B. M.

    1993-01-01

    The past orbital evolution of Mars is examined in relation to changes in ice stability as well as the condensation, sublimation, and diffusion of atmospheric water in an exchange with the regolith. The Martian obliquity has undergone significant oscillations in its recent past. During periods of high obliquity, the solar energy would have been distributed such that the equatorial and midlatitude regions would have been colder that at present and the polar regions would have been warmer. Warmer polar regions would result in the sublimation of more polar cap water into the atmosphere and thus higher atmospheric water abundances. This combination of effects would have resulted in ground ice being stable globally. During periods of low obliquity the opposite would have occurred. Modeling results of the regolith thermal behavior and the molecular diffusion of water vapor within the regolith and in exchange with the atmosphere have shown significant quantities of ground ice can form at all latitudes within the top 50 cm to 1 m of the regolith during periods of high obliquity. The amount of ice that forms can be as much as the regolith pores can hold. During low obliquity most or all of this ice sublimes and diffuses away. Below this depth a longer-term stability is observed at some latitudes where ice steadily increases in concentration regardless of orbital oscillations that occur.

  4. Moessbauer Mineralogy on the Moon: The Lunar Regolith

    NASA Technical Reports Server (NTRS)

    Morris, Richard V.; Korotev, Randy L..; Shelfer, Tad D.; Klingelhoefer, Goestar

    1997-01-01

    A first-order requirement for spacecraft missions that land on solid planetary objects is instrumentation for mineralogical analyses. For purposes of providing diagnostic information about naturally-occurring materials, the element iron is particularly important because it is abundant and multivalent. Knowledge of the oxidation state of iron and its distribution among iron-bearing mineralogies tightly constrains the types of materials present and provides information about formation and modification (weathering) processes. Because Moessbauer spectroscopy is sensitive to both the valence of iron and its local chemical environment, the technique is unique in providing information about both the relative abundance of iron-bearing phases and oxidation state of the iron. The Moessbauer mineralogy of lunar regolith samples (primarily soils from the Apollo 16 and 17 missions to the Moon) were measured in the laboratory to demonstrate the strength of the technique for in situ mineralogical exploration of the Moon. The regolith samples were modeled as mixtures of five iron-bearing phases: olivine, pyroxene, glass, ilmenite, and metal. Based on differences in relative proportions of iron associated with these phases, volcanic ash regolith can be distinguished from impact-derived regolith, impact-derived soils of different geologic affinity (e.g., highlands, maria) can be distinguished on the basis of their constituent minerals, and soil maturity can be estimated. The total resonant absorption area of the Moessbauer spectrum can be used to estimate total FeO concentrations.

  5. Investigation of the flow characteristics of lunar regolith simulants under reduced gravity and vacuum on a partial-g parabolic flight

    NASA Astrophysics Data System (ADS)

    Reiss, Philipp; Hager, Philipp

    2013-04-01

    In the field of planetary and asteroid exploration missions, one of the main interests is to gain knowledge about the components of the local Regolith to understand the properties and formation of these objects and to possibly use bound elements for in-situ resource utilization (ISRU). The handling and transport of Regolith, especially within smaller scientific sampling devices and analysis instruments, is a central issue that is often underestimated. Due to its physical properties, lunar Regolith for instance has an increased risk of clogging conveying and processing devices and hence complicates the design of such systems. In most current concepts for lunar and Martian exploration missions, the excavated Regolith is fed to a storage or analysis instrument through a series of hoppers, pipes, and similar devices. This transport process is mainly affected by the flow characteristics of the Regolith, and reduced flowability or clogging could impact the success of any mission trying to handle, sample or process Regolith. As part of the Lunar In-situ Resource Experiment (LUISE), transport processes for lunar Regolith were examined. A series of experiments with representative funnel geometries were conducted on a partial-g parabolic flight under 0.38g Martian and 0.16g lunar gravity. The experiments aimed to examine key parameters for hopper designs used in sampling processes for science experiments or ISRU processes on Mars and Moon. Two different representative lunar Regolith simulants, JSC-1A and NU-LHT-2M, were used in the investigation (sample mass < 50g, grain size < 2mm). To avoid gas inclusions in the porous simulant material, the experiments were conducted under a low vacuum between 10-3 and 100kPa. 21 different funnel geometries with variable inclination angle and opening width were tested. They were designed similar to an hourglass, with two different funnels on each side. The material flow was initiated by turning the assembly upside-down. The inclination angles of the funnels varied from 55deg to 75deg in 5deg steps, both in symmetrical and asymmetrical configuration. Three opening widths were investigated, namely 8mm, 13mm, and 18mm. Although both simulant materials showed highly variable flow characteristics, a clear direct proportional dependence between flow rate and g-level was observed. With the transition to lower g-levels, the consolidation of the simulant was significantly reduced, so that in some cases the filling level of the respective hoppers raised and prevented further material flow. The cohesive character of both simulants mainly appeared at lunar gravity. Here the material flow of NU-LHT-2M occasionally came to a sudden stop or did not start at all. Steeper and wider hoppers in most cases lead to increased flow rates, whereas geometries with wider openings tended to reduce the flow continuity. Based on these results, guidelines can be established for designing conveying devices to be used for instruments on Mars or Moon.

  6. Hydrogen-Enhanced Lunar Oxygen Extraction and Storage Using Only Solar Power

    NASA Technical Reports Server (NTRS)

    Burton, rodney; King, Darren

    2013-01-01

    The innovation consists of a thermodynamic system for extracting in situ oxygen vapor from lunar regolith using a solar photovoltaic power source in a reactor, a method for thermally insulating the reactor, a method for protecting the reactor internal components from oxidation by the extracted oxygen, a method for removing unwanted chemical species produced in the reactor from the oxygen vapor, a method for passively storing the oxygen, and a method for releasing high-purity oxygen from storage for lunar use. Lunar oxygen exists in various types of minerals, mostly silicates. The energy required to extract the oxygen from the minerals is 30 to 60 MJ/kg O. Using simple heating, the extraction rate depends on temperature. The minimum temperature is approximately 2,500 K, which is at the upper end of available oven temperatures. The oxygen is released from storage in a purified state, as needed, especially if for human consumption. This method extracts oxygen from regolith by treating the problem as a closed batch cycle system. The innovation works equally well in Earth or Lunar gravity fields, at low partial pressure of oxygen, and makes use of in situ regolith for system insulation. The innovation extracts oxygen from lunar regolith using a method similar to vacuum pyrolysis, but with hydrogen cover gas added stoichiometrically to react with the oxygen as it is produced by radiatively heating regolith to 2,500 K. The hydrogen flows over and through the heating element (HE), protecting it from released oxygen. The H2 O2 heat of reaction is regeneratively recovered to assist the heating process. Lunar regolith is loaded into a large-diameter, low-height pancake reactor powered by photovoltaic cells. The reactor lid contains a 2,500 K HE that radiates downward onto the regolith to heat it and extract oxygen, and is shielded above by a multi-layer tungsten radiation shield. Hydrogen cover gas percolates through the perforated tungsten shielding and HE, preventing oxidation of the shielding and HE, and reacting with the oxygen to form water vapor. The water vapor is filtered through solid regolith to remove unwanted extraction byproducts, and then condensed to a liquid state and stored at 300 to 325 K. Conversion to usable oxygen is achieved by pumping liquid water into a high-pressure electrolyzer, storing the gaseous oxygen at high pressure for use, and diverting the hydrogen back to the reactor or to storage. The results from this design effort show that this oxygen-generating concept can be developed in an efficient system with low specific mass. Advantages include use of regolith as an oxygen source, filter, and thermal insulator. The system can be tested in Earth gravity and can be expected to operate similarly in lunar gravity. The system is scalable, either by increasing the power level and output of a standard module, or by employing multiple modules.

  7. Asteroid collisions, craters, regoliths, and lifetimes

    NASA Technical Reports Server (NTRS)

    Chapman, C. R.

    1978-01-01

    Laboratory experiments and computer modeling are used to predict the development of regoliths on all asteroids more than a few tens of kilometers in diameter, allowing for a wide range in the intrinsic strength of asteroidal surface materials. The high frequency of interasteroid collisions requires nearly all asteroids to be fragments of precursors.

  8. A Conceptual Study for the Autonomous Direct Forming of Lunar Regolith into Flexlock (Trademark) Geomats for Lunar Surface Operations

    NASA Technical Reports Server (NTRS)

    Robertson, Luke B.; Hintze, Paul; OConnor, Gregory W.

    2009-01-01

    We describe the conceptual method of an autonomously operable Direct Forming machine that would consume regolith or regolith slag to mold intimately, interlinked elements in a continuous process. The resulting product, one to three meter wide geomats, would be deployed over commonly traversed areas to isolate the astronauts and equipment from underlying dust. The porous geotextile would provide areas for dust settling, thereby mitigating dust impingement on astronaut suits or surface structures. Because of their self-supporting yet flexible structure, these geomats could be assembled into shields and buttresses to protect lunar habitants from radiation, forming a "flexoskeleton" from in situ materials.

  9. Evolution of Circular Polarization Ratio (CPR) Profiles of Kilometer-scale Craters on the Lunar Maria

    NASA Technical Reports Server (NTRS)

    King, I. R.; Fassett, C. I.; Thomson, B. J.; Minton, D. A.; Watters, W. A.

    2017-01-01

    When sufficiently large impact craters form on the Moon, rocks and unweathered materials are excavated from beneath the regolith and deposited into their blocky ejecta. This enhances the rockiness and roughness of the proximal ejecta surrounding fresh impact craters. The interior of fresh craters are typically also rough, due to blocks, breccia, and impact melt. Thus, both the interior and proximal ejecta of fresh craters are usually radar bright and have high circular polarization ratios (CPR). Beyond the proximal ejecta, radar-dark halos are observed around some fresh craters, suggesting that distal ejecta is finer-grained than background regolith. The radar signatures of craters fade with time as the regolith grows.

  10. BRDF of Salt Pan Regolith Samples

    NASA Technical Reports Server (NTRS)

    Georgiev, Georgi T.; Gatebe, Charles K.; Butler, James J.; King, Michael D.

    2008-01-01

    Laboratory Bi-directional Reflectance Distribution Function (BRDF) measurements of salt pan regolith samples are presented in this study in an effort to understand the role of spatial and spectral variability of the natural biome. The samples were obtained from Etosha Pan, Namibia (19.20 deg S, 15.93 deg E, alt. 1100 m). It is shown how the BRDF depends on the measurement geometry - incident and scatter angles and on the sample particle sizes. As a demonstration of the application of the results, airborne BRDF measurements acquires with NASA's Cloud Absorption Radiometer (CAR) over the same general site where the regolith samples were collected are compared with the laboratory results. Good agreement between laboratory measured and field measured BRDF is reported.

  11. Hydrogen Reduction of Lunar Regolith Simulants for Oxygen Production

    NASA Technical Reports Server (NTRS)

    Hegde, U.; Balasubramaniam, R.; Gokoglu, S. A.; Rogers, K.; Reddington, M.; Oryshchyn, L.

    2011-01-01

    Hydrogen reduction of the lunar regolith simulants JSC-1A and LHT-2M is investigated in this paper. Experiments conducted at NASA Johnson Space Center are described and are analyzed utilizing a previously validated model developed by the authors at NASA Glenn Research Center. The effects of regolith sintering and clumping, likely in actual production operations, on the oxygen production rate are studied. Interpretations of the obtained results on the basis of the validated model are provided and linked to increase in the effective particle size and reduction in the intra-particle species diffusion rates. Initial results on the pressure dependence of the oxygen production rate are also presented and discussed

  12. Tools for Asteroid Regolith Operations

    NASA Technical Reports Server (NTRS)

    Mueller, Robert P.; Calle, Carlos I.; Mantovani, James G.

    2013-01-01

    This RFI response is targeting Area 5. Crew Systems for Asteroid Exploration: concepts for lightweight and low volume robotic and extra-vehicular activity (EVA) systems, such as space suits, tools, translation aids, stowage containers, and other equipment.The NASA KSC Surface Systems Office, Granular Mechanics and Regolith Operations (GMRO) Lab and the Electrostatics Surface Physics Lab (ESPL) are dedicated to developing technologies for operating in regolith environments on target body surfaces. We have identified two technologies in our current portfolio that are highly relevant and useful for crews that will visit a re-directed asteroid in Cis-Lunar Space. Both technologies are at a high TRL of 56 and could be rapidly implemented in time for an ARM mission in this decade.

  13. Regolith Advanced Surface Systems Operations Robot (RASSOR) Phase 2 and Smart Autonomous Sand-Swimming Excavator

    NASA Technical Reports Server (NTRS)

    Sandy, Michael

    2015-01-01

    The Regolith Advanced Surface Systems Operations Robot (RASSOR) Phase 2 is an excavation robot for mining regolith on a planet like Mars. The robot is programmed using the Robotic Operating System (ROS) and it also uses a physical simulation program called Gazebo. This internship focused on various functions of the program in order to make it a more professional and efficient robot. During the internship another project called the Smart Autonomous Sand-Swimming Excavator was worked on. This is a robot that is designed to dig through sand and extract sample material. The intern worked on programming the Sand-Swimming robot, and designing the electrical system to power and control the robot.

  14. Lunar Regolith Particle Shape Analysis

    NASA Technical Reports Server (NTRS)

    Kiekhaefer, Rebecca; Hardy, Sandra; Rickman, Douglas; Edmunson, Jennifer

    2013-01-01

    Future engineering of structures and equipment on the lunar surface requires significant understanding of particle characteristics of the lunar regolith. Nearly all sediment characteristics are influenced by particle shape; therefore a method of quantifying particle shape is useful both in lunar and terrestrial applications. We have created a method to quantify particle shape, specifically for lunar regolith, using image processing. Photomicrographs of thin sections of lunar core material were obtained under reflected light. Three photomicrographs were analyzed using ImageJ and MATLAB. From the image analysis measurements for area, perimeter, Feret diameter, orthogonal Feret diameter, Heywood factor, aspect ratio, sieve diameter, and sieve number were recorded. Probability distribution functions were created from the measurements of Heywood factor and aspect ratio.

  15. The Osiris-Rex Mission - Sample Acquisitions Strategy and Evidence for the Nature of Regolith on Asteroid (101955) 1999 RQ36

    NASA Technical Reports Server (NTRS)

    Lauretta, D. S.; Barucci, M. A.; Bierhaus, E. B.; Brucato, J. R.; Campins, H.; Christensen, P. R.; Clark, B. C.; Connolly, H. C.; Dotto, E.; Dworkin, J. P.; hide

    2012-01-01

    NASA selected the OSIRIS-REx Asteroid Sample Return Mission as the third New Frontiers mission in May 2011 [I]. The mission name is an acronym that captures the scientific objectives: Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer. OSIRIS-REx will characterize near-Earth asteroid (101955) 1999 RQ36, which is both the most accessible carbonaceous asteroid [2,3] and one of the most potentially hazardous asteroids known [4]. The primary objective of the mission is to return a pristine sample from this bod, to advance our understanding of the generation, evolution, and maturation of regolith on small bodies.

  16. Nonequilibrium regolith thickness in the Ouachita Mountains

    Treesearch

    Jonathan D. Phillips; Daniel A. Marion; Kenneth Luckow; Kristin R. Adams

    2005-01-01

    Interpretations of regolith and soil thickness in the context of landscape evolution are typically based on the notion that thickness is controlled by the interaction of weathering rates and erosion and tuned to topography. On slideslopes of the Quachita Mountains, Arkansas, however, there is a high degree of local spatial varibilty that is largely unrelated to...

  17. Formation of Siderite in Lunar Regolith Particles During Irradiation for Instrumental Neutron Activation Analysis

    NASA Technical Reports Server (NTRS)

    Zeigler, R. A.; Haskin, L. A.; Jolliff, B. L.; Wang, A.; Korotev, R. L.

    2002-01-01

    Last year we reported on siderite in an Apollo 16 regolith particle. We ascribed this to vapor deposition on the surface of the Moon by cometary or meteorite impact. Subsequent experiments have shown the siderite to be terrestrial contamination. Additional information is contained in the original extended abstract.

  18. Quantification of Efficiency of Beneficiation of Lunar Regolith

    NASA Technical Reports Server (NTRS)

    Trigwell, Steve; Lane, John; Captain, James; Weis, Kyle; Quinn, Jacqueline; Watanabe, Fumiya

    2011-01-01

    Electrostatic beneficiation of lunar regolith is being researched at Kennedy Space Center to enhance the ilmenite concentration of the regolith for the production of oxygen in in-situ resource utilization on the lunar surface. Ilmenite enrichment of up to 200% was achieved using lunar simulants. For the most accurate quantification of the regolith particles, standard petrographic methods are typically followed, but in order to optimize the process, many hundreds of samples were generated in this study that made the standard analysis methods time prohibitive. In the current studies, X-ray photoelectron spectroscopy (XPS) and Secondary Electron microscopy/Energy Dispersive Spectroscopy (SEM/EDS) were used that could automatically, and quickly, analyze many separated fractions of lunar simulant. In order to test the accuracy of the quantification, test mixture samples of known quantities of ilmenite (2, 5, 10, and 20 wt%) in silica (pure quartz powder), were analyzed by XPS and EDS. The results showed that quantification for low concentrations of ilmenite in silica could be accurately achieved by both XPS and EDS, knowing the limitations of the techniques. 1

  19. Exchange of adsorbed H2O and CO2 between the regolith and atmosphere of Mars caused by changes in surface insolation

    NASA Technical Reports Server (NTRS)

    Fanale, F. P.; Cannon, W. A.

    1974-01-01

    Estimates have been made of the capacity of the Martian regolith to exchange adsorbed H2O and CO2 with the atmosphere-plus-cap system (APCS). These estimates are based upon measured isotherms for H2O and CO2 adsorption on pulverized basalt at low temperatures and on theoretical considerations. A unit column (1 sq cm) of regolith with a deep subsurface temperature of -77 C, considered average for the disk, will contain about 0.4 g of adsorbed CO2 and about 1 g of adsorbed H2O per meter of depth. Under favorable circumstances the top 3 cm can exchange much more H2O with the lower atmosphere each day than is necessary to produce the diurnal brightening. The process appears to be seasonally reversible. The total regolith may contain, in the adsorbed phase alone, as much as 1% of the H2O and 5% of the CO2 surface inventories expected for a hypothetical Mars that has experienced degassing as intensive as that of earth.

  20. Impact Record of a Asteroid Regolith Recorded in a Carbonaceous Chrondrite

    NASA Technical Reports Server (NTRS)

    Zolensky, Michael; Mikouchi, Takashi; Hagiya, Kenji; Ohsumi, Kazumasa; Komatsu, Mutsumi; Chan, Queenie H. S.; Le, Loan; Kring, David; Cato, Michael; Fagan, Amy L.; hide

    2017-01-01

    C-class asteroids frequently exhibit reflectance spectra consistent with thermally metamor-phosed carbonaceous chondrites [1], or a mixture of phyllosilicate-rich material along with regions where they are absent [2]. One particularly important example appears to be asteroid 162173 Ryugu, the target of the Hayabusa 2 mission [1], although most spectra of Ryugu are featureless, suggesting a heterogeneous regolith [3]. Here we explore an alternative cause of dehydration of regolith of C-class asteroids - impact shock melting. Impact shock melting has been proposed to ex-plain some mineralogical characteristics of CB chondrites [4], but has rarely been considered a major process for hydrous carbonaceous chondrites [5]. Jbilet Winselwan (JW) is a very fresh CM breccia from Morocco, with intriguing characteristics. While some lithologies are typical of CM2s (Figure 1, top), other clasts show evidence of brief, though significant impact brecciation and heating. The first evidence for this came from preliminary petrographic and stable isotope studies [6,7]. We contend that highly-brecciated, partially-shocked, and dehydrated lithologies like those in JW dominate C-class asteroid regolith.

  1. Lunar in situ resource utilization by activated thermites

    NASA Astrophysics Data System (ADS)

    Hobosyan, Mkhitar; Martirosyan, Karen

    2011-10-01

    NASA's anticipated returns to the Moon by 2020, subsequent establishment of lunar in situ resource utilization technologies are essential. The surface of Moon is covered with small eroded particles of regolith called lunar dust that adheres electro-statically to everything coming in contact with it, and is of much concern for future lunar base because of its continual mitigation. The next major concern is the protection of equipment and personnel in long term expeditions from harmful UV radiation, which can be made by constructing protective buildings. For construction of permanent structures it is highly desired to have regular shaped sintered regolith with utilization of local materials and with minimum energy consumption. In this study the concept of sintering of lunar regolith with activated thermite reactions is discussed. The thermodynamic calculations as well as the experimental procedure is provided to prove the effectiveness of activated thermites for regolith sintering using local lunar resources with a low (15 wt. %) concentration of aluminum or magnesium. The thermite method is much more energy efficient than the other sintering methods suggested in literature.

  2. Appalachian piedmont regolith: Relations of saprolite and residual soils to rock-type

    USGS Publications Warehouse

    Pavich, M.J.

    1996-01-01

    Saprolite is a major product of rock weathering on the Appalachian Piedmont from New Jersey to Alabama. On the Piedmont, it is the primary substrate from which residual soils are developed. Properties of saprolite and residual soils are highly related to their parent rocks. Studies of cores and outcrops illustrate that rock structure and mineralogy control upland regolith zonation. Saprolite develops by in situ chemical alteration of a wide variety of mafic to highly silicic rocks. Thickness of upland saprolite varies from a few meters on mafic rocks to tens of meters on silicic rocks. Saprolite thickness decreases with increasing slope and saprolite is generally thin or absent in valley bottoms. Massive residual subsoils and soils develop by physical and chemical processes that alter the upper few meters of saprolite. The fabric, texture and mineralogy of residual soils are distinctly different from underlying saprolite. The boundary between soil and saprolite is often gradual, and often a zone of low permeability. Geologic maps are useful guides to Piedmont regolith thickness and zonation. In regional design studies, geologic maps and regolith characteristics can be useful in environmental decision-making.

  3. Aiming Optimum Space Radiation Protection using Regolith.

    NASA Astrophysics Data System (ADS)

    Masuda, Daisuke; Nagamatsu, Aiko; Indo, Hiroko; Iwashita, Yoichiro; Suzuki, Hiromi; Shimazu, Toru; Yano, Sachiko; Tanigaki, Fumiaki; Ishioka, Noriaki; Mukai, Chiaki; Majima, Hideyuki J.

    Radiation protection of space radiation is very important factor in manned space activity on the moon. At the construction of lunar base, low cost radiation shielding would be achieved using regolith that exists on the surface of the moon. We studied radiation shielding ability of regolith as answer the question, how much of depth would be necessary to achieve minimum radiation protection. We estimated the shielding ability of regolith against each atomic number of space radiation particles. Using stopping power data of ICRU REPORT49 and 73, we simulated the approximate expression (function of the energy of the atomic nucleus as x and the atomic number as Z) of the stopping power for the space proton particle (nucleus of H) against silicon dioxide (SiO2), aluminum oxide (Al2O3), and iron (Fe), which are the main components of regolith. Based on the expression, we applied the manipulation to the other particles of space radiation to up to argon particle (Ar). These simulated expressions complied well the data of ICRU REPORT49 and 73 except alpha particle (nucleus of He). The simulation values of stop-ping power of ten elements from potassium to nickel those we had no data in ICRU REPORT were further simulated. Using the obtained expressions, the relationship between the radiation absorbed dose and depth of a silicon dioxide was obtained. The space radiation relative dose with every depth in the moon could be estimated by this study.

  4. A One-Piece Lunar Regolith-Bag Garage Prototype

    NASA Technical Reports Server (NTRS)

    Smithers, Gweneth A.; Nehls, Mary K.; Hovater, Mary A.; Evans, Steven W.; Miller, J. Scott; Broughton, Roy M., Jr.; Beale, David; Killinc-Balci, Fatma

    2006-01-01

    Shelter structures on the moon, even in early phases of exploration, should incorporate lunar materials as much as possible. We designed and constructed a prototype for a one-piece regolith-bag unpressurized garage concept, and, in parallel, we conducted a materials testing program to investigate six candidate fabrics to learn how they might perform in the lunar environment. In our concept, a lightweight fabric form is launched from Earth to be landed on the lunar surface and robotically filled with raw lunar regolith. In the materials testing program, regolith-bag fabric candidates included: VectranTM, NextelTM, Gore PTFE FabricTM, ZylonTM TwaronTM and NomexTM. Tensile (including post radiation exposure), fold, abrasion, and hypervelocity impact testing were performed under ambient conditions, and, within our current means, we also performed these tests under cold and elevated temperatures. In some cases, lunar simulant (JSC-1) was used in conjunction with testing. Our ambition is to continuously refine our testing to reach lunar environmental conditions to the extent possible. A series of preliminary structures were constructed during design of the final prototype. Design is based on the principles of the classic masonry arch. The prototype was constructed of KevlarTM and filled with vermiculite (fairly close to the weight of lunar regolith on the moon). The structure is free-standing, but has not yet been load tested. Our plan for the future would be to construct higher fidelty mockups with each iteration, and to conduct appropriate tests of the structure.

  5. A One-Piece Lunar Regolith-Bag Garage Prototype

    NASA Technical Reports Server (NTRS)

    Smithers, Gweneth A.; Nehls, Mary K.; Hovater, Mary A.; Evans, Steven W.; Miller, J. Scott; Broughton, Roy M.; Beale, David; Killing-Balci, Fatma

    2007-01-01

    Shelter structures on the moon, even in early phases of exploration, should incorporate lunar materials as much as possible. We designed and constructed a prototype for a one-piece regolith-bag unpressurized garage concept, and, in parallel, we conducted a materials testing program to investigate six candidate fabrics to learn how they might perform in the lunar environment. In our concept, a lightweight fabric form is launched from Earth to be landed on the lunar surface and robotically filled with raw lunar regolith. In the materials testing program, regolith-bag fabric candidates included: Vectran(TM), Nextel(TM), Gore PTFE Fabric(TM), Zylon(TM), Twaron(TM), and Nomex(TM). Tensile (including post radiation exposure), fold, abrasion, and hypervelocity impact testing were performed under ambient conditions, and, within our current means, we also performed these tests under cold and elevated temperatures. In some cases, lunar simulant (JSC-1) was used in conjunction with testing. Our ambition is to continuously refine our testing to reach lunar environmental conditions to the extent possible. A series of preliminary structures were constructed during design of the final prototype. Design is based on the principles of the classic masonry arch. The prototype was constructed of Kevlar(TM) and filled with vermiculite (fairly close to the weight of lunar regolith on the moon). The structure is free-standing, but has not yet been load tested. Our plan for the future would be to construct higher fidelity mockups with each iteration, and to conduct appropriate tests of the structure.

  6. Global Variations in Regolith Properties on Asteroid Vesta from Dawn's Low-Altitude Mapping Orbit

    NASA Technical Reports Server (NTRS)

    Denevi, Brett W.; Beck, Andrew W.; Coman, Ecaterina; Thomson, Bradley J.; Ammannito, Eleonora; Blewett, David T.; Sunshine, Jessica M.; De Sanctis, Maria Cristina; Li, Jian-Yang; Marchi, Simone; hide

    2016-01-01

    We investigate the depth, variability, and history of regolith on asteroid Vesta using data from the Dawn spacecraft. High-resolution (15-20 m pixel(sup -1)) Framing Cameraimages are used to assess the presence of morphologic indicators of a shallow regolith,including the presence of blocks in crater ejecta, spur-and-gully-type features in crater walls,and the retention of small (less than 300 m) impact craters. Such features reveal that the broad,regional heterogeneities observed on Vesta in terms of albedo and surface composition extend to the physical properties of the upper approx. 1 km of the surface. Regions of thin regolithare found within the Rheasilvia basin and at equatorial latitudes from approx. 0-90 deg. E and approx.260-360 deg. E. Craters in these areas that appear to excavate material from beneath the regolithhave more diogenitic (Rheasilvia, 090 deg. E) and cumulate eucrite (260-360 deg. E) compositions.A region of especially thick regolith, where depths generally exceed 1 km, is found from approx.100-240 deg. E and corresponds to heavily cratered, low-albedo surface with a basaltic eucritecomposition enriched in carbonaceous chondrite material. The presence of a thick regolithin this area supports the idea that this is an ancient terrain that has accumulated a larger component of exogenic debris. We find evidence for the gardening of crater ejecta towardmore howarditic compositions, consistent with regolith mixing being the dominant form of "weathering" on Vesta.

  7. RESOLVE Projects: Lunar Water Resource Demonstration and Regolith Volatile Characterization

    NASA Technical Reports Server (NTRS)

    2008-01-01

    To sustain affordable human and robotic space exploration, the ability to live off the land at the exploration site will be essential. NASA calls this ability in situ resource utilization (ISRU) and is focusing on finding ways to sustain missions first on the Moon and then on Mars. The ISRU project aims to develop capabilities to technology readiness level 6 for the Robotic Lunar Exploration Program and early human missions returning to the Moon. NASA is concentrating on three primary areas of ISRU: (1) excavating, handling, and moving lunar regolith, (2) extracting oxygen from lunar regolith, and (3) finding, characterizing, extracting, separating, and storing volatile lunar resources, especially in the permanently shadowed polar craters. To meet the challenges related to technology development for these three primary focus areas, the Regolith and Environment Science and Oxygen and Lunar Volatile Extraction (RESOLVE) project was initiated in February 2005, through funding by the Exploration Systems Mission Directorate. RESOLVE's objectives are to develop requirements and conceptual designs and to perform breadboard concept verification testing of each experiment module. The final goal is to deliver a flight prototype unit that has been tested in a relevant lunar polar environment. Here we report progress toward the third primary area creating ways to find, characterize, extract, separate, and store volatile lunar resources. The tasks include studying thermal, chemical, and electrical ways to collect such volatile resources as hydrogen, water, nitrogen, methane, and ammonia. We approached this effort through two subtasks: lunar water resource demonstration (LWRD) and regolith volatile characterization (RVC).

  8. Lunar Simulants: JSC-1 is Gone; The Need for New Standardized Root Simulants

    NASA Technical Reports Server (NTRS)

    Carter, James L.; McKay, David S.; Taylor, Lawrence A.; Carrier, W. David, III

    2004-01-01

    A workshop was held in 1991 to evaluate the status of simulated lunar regolith material and to make recommendations on future requirements and production of such material. As an outgrowth of that workshop, a group centered at Johnson Space Center (JSC) teamed with James Carter of the University of Texas at Dallas and Walter Boles of Texas A&M University to produce and distribute a new standardized lunar regolith simulant termed JSC-1. Carter supervised the field collection, shipping, processing, and initial packaging and transportation of JSC-1. Boles stored and distributed JSC-1. About 25 tons were created and distributed to the lunar science and engineer community; none is left for distribution. JSC-1 served an important role in concepts and designs for lunar base and lunar materials processing. Its chemical and physical properties were described by McKay et al., with its geotechnical properties described by Klosky et al.. While other lunar regolith simulants were produced before JSC-1, they were not standardized, and results from tests performed on them were not necessarily equivalent to test results performed on JSC-1. JSC-1 was designed to be chemically, mineralogically, and texturally similar to a mature lunar mare regolith (low titanium). The glass-rich character of JSC-1 (approx. 50%) produced quite different properties compared to other simulants that were made entirely of comminuted crystalline rock, but properties similar to lunar mare near surface regolith.

  9. ISRU 3D printing for habitats and structures on the Moon

    NASA Astrophysics Data System (ADS)

    Cowley, Aidan

    2016-07-01

    In-situ-resource utilisation (ISRU) in combination with 3D printing may evolve into a key technology for future exploration. Setting up a lunar facility could be made much simpler by using additive manufacturing techniques to build elements from local materials - this would drastically reduce mission mass requirements and act as an excellent demonstrator for ISRU on other planetary bodies. Fabricating structures and components using Lunar regolith is an area of interest for ESA, as evidenced by past successful General Studies Program (GSP) and ongoing technology development studies. In this talk we detail a number of projects looking into the behavior of Lunar regolith simulants, their compositional variants and approaches to sintering such material that are under-way involving EAC, ESTEC and DLR. We report on early studies into utilizing conventional thermal sintering approaches of simulants as well as microwave sintering of these compositions. Both techniques are candidates for developing a 3D printing methodology using Lunar regolith. It is known that the differences in microwave effects between the actual lunar soil and lunar simulants can be readily ascribed to the presence of nanophase metallic Fe, native to Lunar regolith but lacking in simulants. In compostions of simulant with increased Illmenite (FeTiO3) concentrations, we observe improved regolith response to microwave heating, and the readily achieved formation of a glassy melt in ambient atmosphere. The improved response relative to untreated simulant is likely owing to the increased Fe content in the powder mix.

  10. Building components for an outpost on the Lunar soil by means of a novel 3D printing technology

    NASA Astrophysics Data System (ADS)

    Cesaretti, Giovanni; Dini, Enrico; De Kestelier, Xavier; Colla, Valentina; Pambaguian, Laurent

    2014-01-01

    3D-printing technologies are receiving an always increasing attention in architecture, due to their potential use for direct construction of buildings and other complex structures, also of considerable dimensions, with virtually any shape. Some of these technologies rely on an agglomeration process of inert materials, e.g. sand, through a special binding liquid and this capability is of interest for the space community for its potential application to space exploration. In fact, it opens the possibility for exploiting in-situ resources for the construction of buildings in harsh spatial environments. The paper presents the results of a study aimed at assessing the concept of 3D printing technology for building habitats on the Moon using lunar soil, also called regolith. A particular patented 3D-printing technology - D-shape - has been applied, which is, among the existing rapid prototyping systems, the closest to achieving full scale construction of buildings and the physical and chemical characteristics of lunar regolith and terrestrial regolith simulants have been assessed with respect to the working principles of such technology. A novel lunar regolith simulant has also been developed, which almost exactly reproduces the characteristics of the JSC-1A simulant produced in the US. Moreover, tests in air and in vacuum have been performed to demonstrate the occurrence of the reticulation reaction with the regolith simulant. The vacuum tests also showed that evaporation or freezing of the binding liquid can be prevented through a proper injection method. The general requirements of a Moon outpost have been specified, and a preliminary design of the habitat has been developed. Based on such design, a section of the outpost wall has been selected and manufactured at full scale using the D-shape printer and regolith simulant. Test pieces have also been manufactured and their mechanical properties have been assessed.

  11. Cohesion of Mm- to Cm-Sized Asteroid Simulant Grains: An Experimental Study

    NASA Astrophysics Data System (ADS)

    Brisset, Julie; Colwell, Joshua E.; Dove, Adrienne; Jarmak, Stephanie; Anderson, Seamus

    2017-10-01

    The regolith covering the surfaces of asteroids and planetary satellites is very different from terrestrial soil particles and subject to environmental conditions very different from what is found on Earth. The loose, unconsolidated granular material has angular-shaped grains and a broad size distribution. On small and airless bodies (<10 km), the solar wind leads to a depletion of fine grains (<100µm) on the surface. Ground observations of the two asteroids currently targeted by spacecraft, Ryugu (Hayabusa-2) and Bennu (OSIRIS-REx), indicate that their surfaces could be covered in mm- to cm-sized regolith grains. As these small bodies have surface gravity levels below 10-5g, g being the Earth surface gravity, the cohesion behavior of the regolith grains will dictate the asteroid’s surface morphology and its response to impact or spacecraft contact.Previous laboratory experiments on low-velocity impacts into regolith simulant with grain sizes <250 µm have revealed a transition of the grain behavior from a gravity-dominated regime to a cohesion-dominated regime when the local gravity level reaches values below 10-3g. This is in good agreement with analytical and simulation studies for these grain sizes. From the expected grain sizes at the surfaces of Ryugu and Bennu, we have now focused on larger grain sizes ranging from mm to cm. We have carried out a series of experiments to study the cohesion behavior of such larger grains of asteroid regolith simulant. The simulant used was CI Orgueil of Deep Space Industries. Experiments included laboratory tabletop avalanching, compression and shear force measurements, as well as low-velocity impacts under microgravity.Our goal is to determine if the grain size distribution has an influence on the cohesion behavior of the regolith and if we can validate numerical simulation results with experimental measurements. We will discuss the implications of our results for sample return or landing missions to small bodies such as asteroids or Martian moons.

  12. Global Landslides on Rapidly Spinning Spheroids

    NASA Astrophysics Data System (ADS)

    Scheeres, Daniel J.; Sanchez, P.

    2013-10-01

    The angle of repose and conditions for global landslides on the surfaces of small, rapidly spinning, spheroidal asteroids are studied. Applying techniques of soil mechanics, we develop a theory for, and examples of, how regolith will fail and flow in this microgravity environment. Our motivation is to develop an understanding of the "top-shaped" class of asteroids based on analytical soil mechanics. Our analysis transforms the entire asteroid surface into a local frame where we can model it as a conventional granular pile with a surface slope, acceleration and height variations as a function of the body's spin rate, shape and density. A general finding is that the lowest point on a rapidly spinning spheroid is at the equator with the effective height of surface material monotonically increasing towards the polar regions, where the height can be larger than the physical radius of the body. We study the failure conditions of both cohesionless and cohesive regolith, and develop specific predictions of the surface profile as a function of the regolith angle of friction and the maximum spin rate experienced by the body. The theory also provides simple guidelines on what the shape may look like, although we do not analyze gravitationally self-consistent evolution of the body shape. The theory is tested with soft-sphere discrete element method granular mechanics simulations to better understand the dynamical aspects of global asteroid landslides. We find significant differences between failure conditions for cohesive and cohesionless regolith. In the case of cohesive regolith, we show that extremely small values of strength (much less than that found in lunar regolith) can stabilize a surface even at very rapid spin rates. Cohesionless surfaces, as expected, fail whenever their surface slopes exceed the angle of friction. Based on our analysis we propose that global landslides and the flow of material towards the equator on spheroidal bodies are precipitated by exogenous effects such as impact induced seismic shaking or torques during planetary flybys.

  13. Dielectric Breakdown Weathering by Solar Energetic Particles Charging Airless Bodies in the Inner Solar System

    NASA Astrophysics Data System (ADS)

    Jordan, A.; Stubbs, T. J.; Wilson, J. K.; Schwadron, N.; Spence, H. E.; Hayne, P. O.; Izenberg, N.

    2016-12-01

    Solar energetic particles (SEPs) can penetrate regoliths of airless bodies to depths of 1 mm and cause deep dielectric charging. This charging is predicted to dissipate slowly (on the order of days) in regoliths with low electrical conductivities, which could form subsurface electric fields (> 106 V/m) large enough to cause dielectric breakdown (or "sparking"). Colder regoliths are expected to have lower conductivities, so the coldest regions of airless planetary bodies can become the most deep dielectrically charged. Consequently, large SEP events may cause dielectric breakdown in these regions, possibly contributing to space weathering on airless bodies in the inner solar system. Previous work has predicted that, in permanently shadowed regions (PSRs) on the Moon, breakdown weathering may have melted and/or vaporized 10-25 wt% of the meteoritically gardened regolith, a percentage comparable to weathering by meteoroid impacts. But much of the Moon's nightside can also reach cold (<100 K) temperatures, so we now show how breakdown weathering may have affected 4-11 wt% of the gardened regolith over the entire lunar surface. We use data from the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) on the Lunar Reconnaissance Orbiter (LRO) to show two examples of SEP events that may have caused breakdown on the Moon. We also scale large SEP events to the orbit of Mars and predict the rate at which they may cause dielectric breakdown on Phobos and Deimos, whose polar regions remain <100 K during their long winters (nearly half an Earth year). On these satellites, the gardening rates are unknown, so we estimate the percentage of regolith affected in these locations as a function of gardening rate. Finally, we briefly show that dielectric breakdown may occur on asteroids that have either high obliquities or PSRs, like Vesta and Ceres, respectively. This work also emphasizes the need for laboratory experiments to inform both remote sensing observations and the analysis of samples already obtained during the Luna and Apollo missions.

  14. Thermophysical properties and modeling of minor bodies regoliths

    NASA Astrophysics Data System (ADS)

    Delbo, M.

    2017-12-01

    I will review recent studies of atmosphere-less Solar System minor bodies in the thermal infrared wavelengths (> 5 micron), which have seen major advances in the last few years thanks to the observations from space telescopes such as NASA's WISE and Spitzer, JAXA's Akari and ESA's Herschel. Analysis of these observations by means of numerical models allowed not only the determination of sizes and albedos for more than hundred-thousands asteroids, but also to infer, for several of these objects, the values of their thermal inertia. The latter is a sensitive indicator for the presence (or absence) of surface regolith, its grain size, porosity, and degree of compaction. These data confirm presence of regolith on all the studied asteroids, even on the rapidly rotating (period < 3 hours) ones. To exaplain this latter result, researchers invoked electrostatic forces to retain the regolith, which otherwise would be lost in space. Furthermore, it appears that thermal inertia inversely correlates with asteroid sizes, and directly correlates with their rotation periods. This can be explained by regolith density increasing with increasing depth below the surface, a phenomenon already noted of our moon. These findings will soon be tested with unprecedented detail by data from NASA's OSIRIS-REx sample return mission to the asteroid Bennu. OSIRIS-REx's instruments will map temperatures of the entire surface at different local times of the day (between 3:20am and 8:40pm) allowing fine sampling of the diurnal temperature curve. This will result in maps of the thermal inertia of the surface at 40 m spatial scale. On atmosphere-less bodies, thermal inertia controls the amplitude and rate of changes of temperature cycles, which can reach several tens of degrees and several degrees per minute, respectively. Laboratory experiments on materials analogs to those expected on asteroids show that these repeated temperature excursions cause stress on the materials, leading to their fragmentation and the production of fresh regolith

  15. Depth of maturity in the Moon's regolith

    NASA Astrophysics Data System (ADS)

    Denevi, B. W.; Duck, A.; Klem, S.; Ravi, S.; Robinson, M. S.; Speyerer, E. J.

    2017-12-01

    The observed maturity of the lunar surface is a function of its exposure to the weathering agents of the space environment as well as the rates of regolith gardening and overturn. Regolith exposed on the surface weathers until it is buried below material delivered to the surface by impact events; weathering resumes when it is re-exposed to the surface environment by later impacts. This cycle repeats until a mature layer of some thickness develops. The gardening rate of the upper regolith has recently been shown to be substantially higher than previously thought, and new insights on the rates of space weathering and potential variation of these rates with solar wind flux have been gained from remote sensing as well as laboratory studies. Examining the depth to which the lunar regolith is mature across a variety of locations on the Moon can provide new insight into both gardening and space weathering. Here we use images from the Lunar Reconnaissance Orbiter Camera (LROC) with pixel scales less than approximately 50 cm to examine the morphology and reflectance of impact craters in the 2- to 100-m diameter size range. Apollo core samples show substantial variation, but suggest that the upper 50 cm to >1 m of regolith is mature at the sampled sites. These depths indicate that because craters excavate to a maximum depth of 10% of the transient crater diameter, craters with diameters less than 5-10 m will typically expose only mature material and this phenomenon should be observable in LROC images. Thus, we present the results of classifying craters by both morphology and reflectance to determine the size-frequency distribution of craters that expose immature material versus those that do not. These results are then compared to observations of reflectance values for the ejecta of craters that have formed during the LRO mission. These newly formed craters span a similar range of diameters, and there is no ambiguity about post-impact weathering because they are less than a decade old.

  16. Adsorption of Water on JSC-1A Lunar Simulant Samples

    NASA Technical Reports Server (NTRS)

    Goering, John; Sah, Shweta; Burghaus, Uwe; Street, Kenneth W.

    2008-01-01

    Remote sensing probes sent to the moon in the 1990s indicated that water may exist in areas such as the bottoms of deep, permanently shadowed craters at the lunar poles, buried under regolith. Water is of paramount importance for any lunar exploration and colonization project which would require self-sustainable systems. Therefore, investigating the interaction of water with lunar regolith is pertinent to future exploration. The lunar environment can be approximated in ultra-high vacuum systems such as those used in thermal desorption spectroscopy (TDS). Questions about water dissociation, surface wetting, degree of crystallization, details of water-ice transitions, and cluster formation kinetics can be addressed by TDS. Lunar regolith specimens collected during the Apollo missions are still available though precious, so testing with simulant is required before applying to use lunar regolith samples. Hence, we used for these studies JSC-1a, mostly an aluminosilicate glass and basaltic material containing substantial amounts of plagioclase, some olivine and traces of other minerals. Objectives of this project include: 1) Manufacturing samples using as little raw material as possible, allowing the use of surface chemistry and kinetics tools to determine the feasibility of parallel studies on regolith, and 2) Characterizing the adsorption kinetics of water on the regolith simulant. This has implications for the probability of finding water on the moon and, if present, for recovery techniques. For condensed water films, complex TDS data were obtained containing multiple features, which are related to subtle rearrangements of the water adlayer. Results from JSC-1a TDS studies indicate: 1) Water dissociation on JSC-1a at low exposures, with features detected at temperatures as high as 450 K and 2) The formation of 3D water clusters and a rather porous condensed water film. It appears plausible that the sub- m sized particles act as nucleation centers.

  17. The Lunar Regolith as a Recorder of Cosmic History

    NASA Technical Reports Server (NTRS)

    Cooper, Bonnie; McKay, D.; Riofrio, L.

    2012-01-01

    The Moon can be considered a giant tape recorder containing the history of the solar system and Universe. The lunar regolith (soil) has recorded the early history of the Moon, Earth, the solar system and Universe. A major goal of future lunar exploration should be to find and play back existing fragments of that tape . By reading the lunar tape, we can uncover a record of planetary bombardment, as well as solar and stellar variability. The Moon can tell us much about our place in the Universe. The lunar regolith has likely recorded the original meteoritic bombardment of Earth and Moon, a violent cataclysm that may have peaked around 4 Gyr, and the less intense bombardment occurring since that time. This impact history is preserved on the Moon as regolith layers, ejecta layers, impact melt rocks, and ancient impact breccias. The impact history of the Earth and Moon possibly had profound effects on the origin and development of life. Decrease in meteor bombardment allowed life to develop on Earth. Life may have developed first on another body, such as Mars, then arrived via meteorite on Earth. The solar system may have experienced bursts of severe radiation from the Sun, other stars, or from unknown sources. The lunar regolith has recorded this radiation history in the form of implanted solar wind, solar flare materials and radiation damage. Lunar soil can be found sandwiched between layers of basalt or pyroclastic deposits. This filling constitutes a buried time capsule that is likely to contain well-preserved ancient regolith. Study of such samples will show us how the solar system has evolved and changed over time. The lunar tape recorder can provide detailed information on specific portions of solar and stellar variability. Data from the Moon also offers clues as to whether so-called fundamental constants have changed over time.

  18. Equatorial ground ice on Mars: Steady-state stability

    NASA Technical Reports Server (NTRS)

    Mellon, Michael T.; Jakosky, Bruce M.; Postawko, Susan E.

    1993-01-01

    Current Martian equatorial surface temperatures are too warm for water ice to exist at the surface for any appreciable length of time before subliming into the atmosphere. Subsurface temperatures are generally warmer still and, despite the presence of a diffusive barrier of porous regolith material, it has been shown by Smoluchowski, Clifford and Hillel, and Fanale et al. that buried ground ice will also sublime and be lost to the atmosphere in a relatively short time. We investigate the behavior of this subliming subsurface ice and show that it is possible for ice to maintain at a steady-state depth, where sublimation and diffusive loss to the atmosphere is balanced by resupply from beneath by diffusion and recondensation of either a deeper buried ice deposits or ground water. We examine the behavior of equatorial ground ice with a numercial time-marching molecular diffusion model. In our model we allow for diffusion of water vapor through a porous regolith, variations in diffusivity and porosity with ice content, and recondensation of sublimed water vapor. A regolith containing considerable amounts of ice can still be very porous, allowing water vapor to diffuse up from deeper within the ice layer where temperatures are warmer due to the geothermal gradient. This vapor can then recondense nearer to the surface where ice had previously sublimed and been lost to the atmosphere. As a result we find that ice deposits migrate to find a steady-state depth, which represents a balance between diffusive loss to the atmosphere through the overlying porous regolith and diffusive resupply through a porous icy regolith below. This depth depends primarily on the long-term mean surface temperature and the nature of the geothermal gradient, and is independent of the ice-free porosity and the regolith diffusivity. Only the rate of loss of ground ice depends on diffusive properties.

  19. Solar Ion Sputter Deposition in the Lunar Regolith: Experimental Simulation Using Focused-Ion Beam Techniques

    NASA Technical Reports Server (NTRS)

    Christoffersen, R.; Rahman, Z.; Keller, L. P.

    2012-01-01

    As regions of the lunar regolith undergo space weathering, their component grains develop compositionally and microstructurally complex outer coatings or "rims" ranging in thickness from a few 10 s to a few 100's of nm. Rims on grains in the finest size fractions (e.g., <20 m) of mature lunar regoliths contain optically-active concentrations of nm size metallic Fe spherules, or "nanophase Fe(sup o)" that redden and attenuate optical reflectance spectral features important in lunar remote sensing. Understanding the mechanisms for rim formation is therefore a key part of connecting the drivers of mineralogical and chemical changes in the lunar regolith with how lunar terrains are observed to become space weathered from a remotely-sensed point of view. As interpreted based on analytical transmission electron microscope (TEM) studies, rims are produced from varying relative contributions from: 1) direct solar ion irradiation effects that amorphize or otherwise modify the outer surface of the original host grain, and 2) nanoscale, layer-like, deposition of extrinsic material processed from the surrounding soil. This extrinsic/deposited material is the dominant physical host for nanophase Fe(sup o) in the rims. An important lingering uncertainty is whether this deposited material condensed from regolith components locally vaporized in micrometeorite or larger impacts, or whether it formed as solar wind ions sputtered exposed soil and re-deposited the sputtered ions on less exposed areas. Deciding which of these mechanisms is dominant, or possibility exclusive, has been hampered because there is an insufficient library of chemical and microstructural "fingerprints" to distinguish deposits produced by the two processes. Experimental sputter deposition / characterization studies relevant to rim formation have particularly lagged since the early post-Apollo experiments of Hapke and others, especially with regard to application of TEM-based characterization techniques. Here we report on a novel design for simulating solar ion sputter deposition in the lunar regolith, with characterization of the resulting sputter deposits by an array of advanced analytical TEM techniques.

  20. Measurements in Vacuum of the Effect of Ilmenite on the Complex Dielectric Permittivity of Planetary Regolith Analog Materials

    NASA Astrophysics Data System (ADS)

    Boivin, A.; Hickson, D.; Cunje, A.; Tsai, C. A.; Ghent, R. R.; Daly, M. G.

    2016-12-01

    When considering radar observations of airless bodies containing regolith, the radar backscattering coefficient is dependent on both the complex permittivity and the thickness of the regolith. The complex permittivity is typically normalized by the permittivity of free space (ɛ0) and reported as the relative permittivity (ɛr = ɛr' + iɛr'', where ɛr' is the dielectric constant and ɛr'' is the loss factor). Given the backscattering coefficient and the dielectric properties of the regolith, it should be possible to determine regolith thickness. This problem has long been considered for the Moon and many measurements of either real or complex permittivity have been made on both Apollo samples and regolith analogues. Measurements thus far have either only been done at a lower frequency range (< 1GHz) than both S Band and X Band radar or did not systematically explore the relationship between complex permittivity and the mineral content. Measurements of geological materials at higher frequencies are, for example, useful for Arecibo S Band (2.38 GHz) as well as Mini-RF X Band (7.14 GHz) Lunar observations, future RIMFAX GPR data from Mars 2020 (150 MHz - 1.2 GHz), and other future radar data at higher frequencies. Systematically exploring the relationship between complex permittivity of regolith and its mineralogical content is particularly relevant for missions to asteroids, such as the OSIRIS-REx mission to (101955) Bennu, where the composition of soil is as of yet unknown. For Lunar materials the presence of the mineral ilmenite (FeTiO3), which contains equal portions FeO and TiO2, is thought to be the dominant factor to control the loss tangent (tanδ, the ratio of ɛr'' to ɛr'). As a starting point into our investigation of the effects of mineralogy on these properties, we present results of dielectric permittivity measurements using a coaxial transmission line in vacuum, which aim to determine the effects of various amounts of ilmenite on the loss tangent of powdered materials. In order to remove moisture from our samples, powders are baked at 250°C for 48hrs and are then placed in a vacuum chamber. Measurements are then made using a sweep of frequencies from 300 kHz to 8.5 GHz. Preliminary results show that ilmenite significantly influences signal attenuation, especially at high concentrations.

  1. Low Temperature (<100K) Regolith Thermal Conductivity - Preliminary Laboratory Data

    NASA Astrophysics Data System (ADS)

    Siegler, M.; Zhong, F.; Woods-Robinson, R.; Paige, D. A.

    2016-12-01

    The Diviner Lunar Radiometer, aboard the Lunar Reconnaissance Orbiter, has shown materials with in the polar cold traps of the Moon to have thermal inertias at least 1 order of magnitude than the rest of the lunar surface. This detection was unexpected, but has a potentially straight-forward explanation in solid state theory (see companion Woods-Robinson et. al. abstract). Thermal conductivity, λ, of a solid should be directly proportional to the specific heat capacity, cp, phonon mean-free path, l, and phonon velocity, v, as: λ(T)=cplvAs temperature decreases, cp also decreases, while l increases. Phonon velocity, v, is generally thought to be constant with temperature. Therefore, thermal conductivity, λ, as a function temperature, T, can be thought of as a battle between cp and l. In crystalline materials, the increase of l with decreasing T generally dominates. However, in polycrystalline materials, like are found on most planetary surfaces, the growth of l (which is fundimantally a measurement of likelihood of phonon scattering) is limited by phonon scattering off of individual grains and subgrain boundaries. In these cases, cpdominates, causing thermal conductivity to plummet at low (<100K for silicate materials) temperatures. Therefore, thermal conductivity as a function of temperature should be inherently related to crystallinity of a given material. In regolith, this solid state drop in material thermal conductivity of polycrystalline materials will act on top of a well understood, but difficult to predict, physical bottleneck of heat transfer at grain contact points. This leads to λ on the order of 10-3 Wm-1K-1 in lunar regolith. Preliminary models predict thermal conductivities on the order 10-5 to 10-4 Wm-1K-1are likely at temperatures below 50K for materials dominated by small crystals (amorphous materials such as glass). Here we report on preliminary laboratory measurements of regolith and regolith simulants down to 15K and 10-7 torr. These results are obtained through an active heated needle measurement within a 10cc samples of regolith from the Apollo 11 and 16 missions at roughly 1500g/cc densities. The samples chamber is nested within a sterling-cooled cryogenic system located at JPL. We will also show results from glass beads (an amorphous "end member") as well as lunar regolith simulants.

  2. The Mixing of Regolith on the Moon and Beyond; A Model Refreshed

    NASA Astrophysics Data System (ADS)

    Costello, E.; Ghent, R. R.; Lucey, P. G.

    2017-12-01

    Meteoritic impactors constantly mix the lunar regolith, affecting stratigraphy, the lifetime of rays and other anomalous surface features, and the burial, exposure, and break down of volatiles and rocks. In this work we revisit the pioneering regolith mixing model presented by Gault et al. (1974), with updated assumptions and input parameters. Our updates significantly widen the parameter space and allow us to explore mixing as it is driven by different impactors in different materials (e.g. radar-dark halos and melt ponds). The updated treatment of micrometeorites suggests a very high rate of processing at the immediate lunar surface, with implications for rock breakdown and regolith production on melt ponds. We find that the inclusion of secondary impacts has a very strong effect on the rate and magnitude of mixing at all depths and timescales. Our calculations are in good agreement with the timescale of reworking in the top 2-3 cm of regolith that was predicted by observations of LROC temporal pairs and by the depth profile of 26Al abundance in Apollo drill cores. Further, our calculations with secondaries included are consistent with the depth profile of in situ exposure age calculated from Is/FeO and cosmic track abundance in Apollo deep drill cores down to 50cm. The mixing we predict is also consistent with the erasure of density anomalies, or `cold spots', observed in the top decimeters of regolith by LRO Diviner, and the 1Gyr lifetime of 1-10m thick Copernican rays. This exploration of Moon's surface evolution has profound implications for our understanding of other planetary bodies. We take advantage of this computationally inexpensive analytic model and apply it to describe mixing on a variety of bodies across the solar system; including asteroids, Mercury, and Europa. We use the results of ongoing studies that describe porosity calculations and cratering laws in porous asteroid-like material to explore the reworking rate experienced by an asteroid. On Mercury, we apply this model to describe the rate at which reworking depletes water ice and calculate the maximum age of Mercury's polar ice deposits. We apply the model to Europa to understand the impact portion of its regolith evolution and provide insight into the sampling zone intended for a future Europa lander.

  3. Chemical weathering in a tropical watershed, Luquillo Mountains, Puerto Rico: I. Long-term versus short-term weathering fluxes

    USGS Publications Warehouse

    White, A.F.; Blum, A.E.; Schulz, M.S.; Vivit, D.V.; Stonestrom, David A.; Larsen, M.; Murphy, S.F.; Eberl, D.

    1998-01-01

    The pristine Rio Icacos watershed in the Luquillo Mountains in eastern Puerto Rico has the fastest documented weathering rate of silicate rocks on the Earth's surface. A regolith propagation rate of 58 m Ma-1 calculated from iso-volumetric saprolite formation from quartz diorite, is comparable to the estimated denudation rate (25-50 Ma-1) but is an order of magnitude faster than the global average weathering rate (6 Ma-1). Weathering occurs in two distinct environments; plagioclase and hornblende react at the saprock interface and biotite and quartz weather in the overlying thick saprolitic regolith. These environments produce distinctly different water chemistries, with K, Mg, and Si increasing linearly with depth in saprolite porewaters and with stream waters dominated by Ca, Na, and Si. Such differences are atypical of less intense weathering in temperate watersheds. Porewater chemistry in the shallow regolith is controlled by closed-system recycling of inorganic nutrients such as K. Long-term elemental fluxes through the regolith (e.g., Si = 1.7 ?? 10-8 moles m-2 s-1) are calculated from mass losses based on changes in porosity and chemistry between the regolith and bedrock and from the age of the regolith surface (200 Ma). Mass losses attributed to solute fluxes are determined using a step-wise infiltration model which calculates mineral inputs to the shallow and deep saprolite porewaters and to stream water. Pressure heads decrease with depth in the shallow regolith (-2.03 m H2O m-1), indicating that both increasing capillary tension and graviometric potential control porewater infiltration. Interpolation of experimental hydraulic conductivities produces an infiltration rate of 1 m yr-1 at average field moisture saturation which is comparable with LiBr tracer tests and with base discharge from the watershed. Short term weathering fluxes calculated from solute chemistries and infiltration rates (e.g., Si = 1.4 ?? 10-8 moles m-2 s-1) are compared to watershed flux rates (e.g., Si = 2.7 ?? 10-8 moles m-2 s-1). Consistency between three independently determined sets of weathering fluxes imply that possible changes in precipitation, temperature, and vegetation over the last several hundred thousand years have not significantly impacted weathering rates in the Luquillo Mountains of Puerto Rico. This has important ramifications for tropical environments and global climate change. Copyright ?? 1998 Elsevier Science Ltd.

  4. Modeling Radar Scattering by Planetary Regoliths for Varying Angles of Incidence

    NASA Astrophysics Data System (ADS)

    Prem, P.; Patterson, G. W.; Zimmerman, M. I.

    2017-12-01

    Bistatic radar observations can play an important role in characterizing the texture and composition of planetary regoliths. Multiple scattering within a closely-packed particulate medium, such as a regolith, can lead to a response referred to as the Coherent Backscatter Opposition Effect (CBOE), associated with an increase in the intensity of backscattered radiation and an increase in Circular Polarization Ratio (CPR) at small bistatic angles. The nature of the CBOE is thought to depend not only on regolith properties, but also on the angle of incidence (Mishchenko, 1992). The latter factor is of particular interest in light of recent radar observations of the Moon over a range of bistatic and incidence angles by the Mini-RF instrument (on board the Lunar Reconnaissance Orbiter), operating in bistatic mode with a ground-based transmitter at the Arecibo Observatory. These observations have led to some intriguing results that are not yet well-understood ­- for instance, the lunar South Polar crater Cabeus shows an elevated CPR at only some combinations of incidence angle/bistatic angle, a potential clue to the depth distribution of water ice at the lunar poles (Patterson et al., 2017). Our objective in this work is to develop a model for radar scattering by planetary regoliths that can assist in the interpretation of Mini-RF observations. We approach the problem by coupling the Multiple Sphere T-Matrix (MSTM) code of Mackowski and Mishchenko (2011) to a Monte Carlo radiative transfer model. The MSTM code is based on the solution of Maxwell's equations for the propagation of electromagnetic waves in the presence of a cluster of scattering/absorbing spheres, and can be used to model the scattering of radar waves by an aggregation of nominal regolith particles. The scattering properties thus obtained serve as input to the Monte Carlo model, which is used to simulate radar scattering at larger spatial scales. The Monte Carlo approach has the advantage of being able to readily accommodate varying incidence angles, as well as heterogeneities in regolith composition and properties - factors that may be of interest in both lunar and other contexts. We will report on the development and validation of the coupled MSTM-Monte Carlo model, and discuss its application to problems of interest.

  5. The opposition effect in Saturn's main rings as seen by Cassini ISS: 4. Correlations of the surge morphology with surface albedos and VIMS spectral properties

    NASA Astrophysics Data System (ADS)

    Déau, Estelle; Dones, Luke; Mishchenko, Michael I.; West, Robert A.; Helfenstein, Paul; Hedman, Matt M.; Porco, Carolyn C.

    2018-05-01

    In this paper, we continue our analysis of the saturnian ring opposition effect seen by Cassini ISS. The ring opposition effect is a peak in the rings' reflectivity caused as the directions from a spot on the rings to the observer and to the light source, respectively, converge toward zero degrees. So far, the exact origin of the ring's opposition effect is still a matter of debate. In our previous work (Déau, et al., 2013, Icarus, 226, 591-603), we compared the opposition effect morphology with the rings' optical depth and found that only the slope of the linear part of the rings' phase curves was strongly correlated with the optical depth. We interpreted this as an indication of the predominant role of interparticle shadowing at moderate phase angles (α ∼ 10-40o). More recently (Déau, 2015, Icarus, 253, 311-345), we showed that interparticle shadowing cannot explain the behavior at low phase angles (α < 1o), indirectly confirming our 2013 result. These findings led to the idea that coherent backscattering is preponderant at the smallest phase angles. Coherent backscattering depends on the microscopic scale of the regolith, and there is a growing body of evidence that regolith grain size, porosity, roughness, and composition control the opposition surge behavior for α < 1o. To test this hypothesis, we compare the opposition surge morphology to the regolith albedo and other spectral properties related to the regolith, such as water ice band depths and spectral slopes derived from Cassini VIMS data (Hedman et al., 2013, Icarus, 223, 105-130). Indeed, it has been recently proven that coherent backscattering affects the water ice band depth variations with phase angle for icy saturnian regoliths (Kolokolova et al., 2010, The Astrophysical Journal Letters, 711, L71-L74). We find that the opposition surge morphology is strongly correlated with the water ice band depth and the regolith albedo. We interpret this finding as an indication that coherent backscattering plays a role in affecting both the water ice band depths and the opposition surge at low phase angles (α < 1o). As the regolith albedo and spectral properties are related to the grain size, porosity, roughness, and composition, we try to assess which of these regolith properties are preponderant in coherent backscattering. Our study is able to narrow down the parameter space of these properties, whose values allow a good match between the angular width predicted by models of coherent backscattering and the width of the observed peak.

  6. Mercury's Weather-Beaten Surface: Understanding Mercury in the Context of Lunar and Asteroidal Space Weathering Studies

    NASA Technical Reports Server (NTRS)

    Domingue, Deborah L.; Chapman, Clark. R.; Killen, Rosemary M.; Zurbuchen, Thomas H.; Gilbert, Jason A.; Sarantos, Menelaos; Benna, Mehdi; Slavin, James A.; Schriver, David; Travnicek, Pavel M.; hide

    2014-01-01

    Mercury's regolith, derived from the crustal bedrock, has been altered by a set of space weathering processes. Before we can interpret crustal composition, it is necessary to understand the nature of these surface alterations. The processes that space weather the surface are the same as those that form Mercury's exosphere (micrometeoroid flux and solar wind interactions) and are moderated by the local space environment and the presence of a global magnetic field. To comprehend how space weathering acts on Mercury's regolith, an understanding is needed of how contributing processes act as an interactive system. As no direct information (e.g., from returned samples) is available about how the system of space weathering affects Mercury's regolith, we use as a basis for comparison the current understanding of these same processes on lunar and asteroidal regoliths as well as laboratory simulations. These comparisons suggest that Mercury's regolith is overturned more frequently (though the characteristic surface time for a grain is unknown even relative to the lunar case), more than an order of magnitude more melt and vapor per unit time and unit area is produced by impact processes than on the Moon (creating a higher glass content via grain coatings and agglutinates), the degree of surface irradiation is comparable to or greater than that on the Moon, and photon irradiation is up to an order of magnitude greater (creating amorphous grain rims, chemically reducing the upper layers of grains to produce nanometer scale particles of metallic iron, and depleting surface grains in volatile elements and alkali metals). The processes that chemically reduce the surface and produce nanometer-scale particles on Mercury are suggested to be more effective than similar processes on the Moon. Estimated abundances of nanometer-scale particles can account for Mercury's dark surface relative to that of the Moon without requiring macroscopic grains of opaque minerals. The presence of nanometer-scale particles may also account for Mercury's relatively featureless visible-near-infrared reflectance spectra. Characteristics of material returned from asteroid 25143 Itokawa demonstrate that this nanometer-scale material need not be pure iron, raising the possibility that the nanometer-scale material on Mercury may have a composition different from iron metal [such as (Fe,Mg)S]. The expected depletion of volatiles and particularly alkali metals from solar-wind interaction processes are inconsistent with the detection of sodium, potassium, and sulfur within the regolith. One plausible explanation invokes a larger fine fraction (grain size less than 45 micron) and more radiation-damaged grains than in the lunar surface material to create a regolith that is a more efficient reservoir for these volatiles. By this view the volatile elements detected are present not only within the grain structures, but also as adsorbates within the regolith and deposits on the surfaces of the regolith grains. The comparisons with findings from the Moon and asteroids provide a basis for predicting how compositional modifications induced by space weathering have affected Mercury's surface composition.

  7. Low Temperature Regolith Bricks for In-Situ Structural Material

    NASA Technical Reports Server (NTRS)

    Grossman, Kevin; Sakthivel, Tamil S.; Mantovani, James; Seal, Sudipta

    2016-01-01

    Current technology for producing in-situ structural materials on future missions to Mars or the moon relies heavily on energy-intensive sintering processes to produce solid bricks from regolith. This process requires heating the material up to temperatures in excess of 1000 C and results in solid regolith pieces with compressive strengths in the range of 14000 to 28000 psi, but are heavily dependent on the porosity of the final material and are brittle. This method is currently preferred over a low temperature cementation process to prevent consumption of precious water and other non-renewable materials. A high strength structural material with low energy requirements is still needed for future colonization of other planets. To fulfill these requirements, a nano-functionalization process has been developed to produce structural bricks from regolith simulant and shows promising mechanical strength results. Functionalization of granular silicate particles into alkoxides using a simple low temperature chemical process produces a high surface area zeolite particles that are held together via inter-particle oxygen bonding. Addition of water in the resulting zeolite particles produces a sol-gel reaction called "inorganic polymerization" which gives a strong solid material after a curing process at 60 C. The aqueous solution by-product of the reaction is currently being investigated for its reusability; an essential component of any ISRU technology. For this study, two batches of regolith bricks are synthesized from JSC-1A; the first batch from fresh solvents and chemicals, the second batch made from the water solution by-product of the first batch. This is done to determine the feasibility of recycling necessary components of the synthesis process, mainly water. Characterization including BET surface area, SEM, and EDS has been done on the regolith bricks as well as the constituent particles,. The specific surface area of 17.53 sq m/g (average) of the granular regolith material was obtained from nitrogen adsorption isotherm measurement. The size, shape and textures of regolith from SEM shows that the particles are 25-50 micrometers in size and mostly irregular in shape (Figure 1a). The elemental composition of regolith was identified from EDS analysis showed the presence of Si, Al, Fe, Na, Mg, Ca, Ti, O and C (see figure 1b). Each set of cylindrical brick samples were prepared by low energy process, and cured for 21 and 28 days, respectively to compare their compressive strength. Figure 1c, and d shows the JSC-1A brick and the compressive strength measurements. The results from the 21 day cured bricks (2 bricks) have been done and yielded an aver-age strength of 3050 psi, considerably higher than Portland cement mortars (Type IV and V). This promising technology provides the benefits of construction material similar to concrete, with a low complexity, low energy synthesis process and the likelihood of complete reusability of precious resources. Compressive strength using this method can be improved by increasing the surface area of the particles, using bi-modal particle size distribution, and adding certain additives to increase inter-particle forces.

  8. Lunabotics Mining: Evolution of ARTEMIS PRIME

    NASA Technical Reports Server (NTRS)

    Bertke, Sarah; Gries, Christine; Huff, Amanda; Logan, Brittany; Oliver, Kaitlin; Rigney, Erica; Tyree, Whitney; Young, Maegan

    2010-01-01

    This slide presentation reviews the development of Amassing Regolith with Topper Engineers eMploying Innovative Solutions (ARTEMIS) in a competition to develop robotic lunar mining capabilities. The goal of the competition was to design, build and operate a remotely controlled device that is capable of excavating, transporting and discharging lunar regolith simulant in a lunar environment over a 13 minute period.

  9. Mineralogical and chemical properties of the lunar regolith

    NASA Astrophysics Data System (ADS)

    McKay, D. S.; Ming, D. W.

    The composition of lunar regolith and its attendant properties are discussed. Tables are provided listing lunar minerals, the abundance of plagioclase feldspar, pyroxene, olivine, and ilmenite in lunar materials, typical compositions of common lunar minerals, and cumulative grain-size distribution for a large number of lunar soils. Also provided are charts on the chemistry of breccias, the chemistry of lunar glass, and the comparative chemistry of surface soils for the Apollo sites. Lunar agglutinates, constructional particles made of lithic, mineral, and glass fragments welded together by a glassy matrix containing extremely fine-grained metallic iron and formed by micrometeoric impacts at the lunar surface, are discussed. Crystalline, igneous rock fragments, breccias, and lunar glass are examined. Volatiles implanted in lunar materials and regolith maturity are also addressed.

  10. Perspective of Life Search in Martian Econiches

    NASA Astrophysics Data System (ADS)

    Demidov, N. E.

    2017-05-01

    Mars may be divided on five ecological niches according to presence and state of water: permanent polar caps, dry regolith, subpermafrost aquifers, cryopegs and ice containing regolith. Basic limiting factors for the search of life in this econiches are: absence of water (dry regolith), depth of burial (cryopegs and subpermafrost aquifers), age (ice containing permafrost and polar caps). High priority targets for the search of life on Mars are represented by permanently frozen deposits of young polar volcanoes and ash layers in polar caps. During volcanic eruptions microorganisms from subpermafrost aquifers could propagate to the surface and survive in permafrost or ice for million years, as it is known to happen on Earth. Possibility of specific lithic habitats in dry layer must also be taken into account.

  11. Mineralogical and chemical properties of the lunar regolith

    NASA Technical Reports Server (NTRS)

    Mckay, David S.; Ming, Douglas W.

    1989-01-01

    The composition of lunar regolith and its attendant properties are discussed. Tables are provided listing lunar minerals, the abundance of plagioclase feldspar, pyroxene, olivine, and ilmenite in lunar materials, typical compositions of common lunar minerals, and cumulative grain-size distribution for a large number of lunar soils. Also provided are charts on the chemistry of breccias, the chemistry of lunar glass, and the comparative chemistry of surface soils for the Apollo sites. Lunar agglutinates, constructional particles made of lithic, mineral, and glass fragments welded together by a glassy matrix containing extremely fine-grained metallic iron and formed by micrometeoric impacts at the lunar surface, are discussed. Crystalline, igneous rock fragments, breccias, and lunar glass are examined. Volatiles implanted in lunar materials and regolith maturity are also addressed.

  12. Investigation of element distributions in Luna-16 regolith

    NASA Astrophysics Data System (ADS)

    Kuznetsov, R. A.; Lure, B. G.; Minevich, V. Ia.; Stiuf, V. I.; Pankratov, V. B.

    1981-03-01

    The concentrations of 32 elements in fractions of different grain sizes in the samples of the lunar regolith brought back by Luna-16 are determined by means of neutron activation analysis. Four groups of elements are distinguished on the basis of the variations of their concentration with grain size, and concentration variations of the various elements with sample depth are also noted. Chemical leaching of the samples combined with neutron activation also reveals differences in element concentrations in the water soluble, metallic, sulphide, phosphate, rare mineral and rock phases of the samples. In particular, the rare earth elements are observed to be depleted in the regolith with respect to chondritic values, and to be concentrated in the phase extracted with 14 M HNO3.

  13. Howardites - Samples of the regolith of the eucrite parent-body: Petrology of Frankfort, Pavlovka, Yurtuk, Malvern, and ALHA 77302

    NASA Technical Reports Server (NTRS)

    Labotka, T. C.; Papike, J. J.

    1980-01-01

    Modal petrographic methods have been applied to the meteorites Frankfort, Pavlovka, Yurtuk, Malvern, and ALHA 77302, to determine some of the characteristics of the regolith of the eucrite parent body. Lithic clasts in the meteorites fall into three major groups: pyroxene + plagioclase rocks, orthopyroxenites, and fused-soil clasts. Lithic clasts make up a small proportion of the soil; mineral clasts from orthopyroxenites dominate the coarse-grained fraction; and the fine-grained fraction contains minerals from both orthopyroxenites and plagioclase + pyroxene rocks. The eucrite regolith appears to have the following characteristics: the source rocks are friable, the soils are immature, comminution is the major soil-forming process, and the soil is well mixed.

  14. Heating-Rate-Coupled Model for Hydrogen Reduction of JSC-1A

    NASA Technical Reports Server (NTRS)

    Hegde, U.; Balasubramaniam, R.; Gokoglu, S. A.

    2010-01-01

    A previously developed and validated model for hydrogen reduction of JSC-1A for a constant reaction-bed temperature is extended to account for reaction during the bed heat-up period. A quasisteady approximation is used wherein an expression is derived for a single average temperature of reaction during the heat-up process by employing an Arrhenius expression for regolith conversion. Subsequently, the regolith conversion during the heat-up period is obtained by using this representative temperature. Accounting for the reaction during heat-up provides a better estimate of the reaction time needed at the desired regolith-bed operating temperature. Implications for the efficiency of the process, as measured by the energy required per unit mass of oxygen produced, are also indicated.

  15. Multiphysics Modeling for Dimensional Analysis of a Self-Heated Molten Regolith Electrolysis Reactor for Oxygen and Metals Production on the Moon and Mars

    NASA Technical Reports Server (NTRS)

    Dominguez, Jesus; Sibille, Laurent

    2010-01-01

    The technology of direct electrolysis of molten lunar regolith to produce oxygen and molten metal alloys has progressed greatly in the last few years. The development of long-lasting inert anodes and cathode designs as well as techniques for the removal of molten products from the reactor has been demonstrated. The containment of chemically aggressive oxide and metal melts is very difficult at the operating temperatures ca. 1600 C. Containing the molten oxides in a regolith shell can solve this technical issue and can be achieved by designing a self-heating reactor in which the electrolytic currents generate enough Joule heat to create a molten bath.

  16. Problem of nature of inert gases in lunar surface material

    NASA Technical Reports Server (NTRS)

    Levskiy, L. K.

    1974-01-01

    The origin of isotopes of inert gases in lunar surface material was investigated from the standpoint of the isotopic two-component status of inert gases in the solar system. Helium and neon represent the solar wind component, while krypton and xenon are planetary gases. Type A gases are trapped by the material of the regolith in the early stages of the existence of the solar system and were brought to the lunar surface together with dust. The material of the regolith therefore cannot be considered as the product of the erosion of the crystalline rocks of the moon and in this sense are extralunar. The regolith material containing type A gases must be identified with the high temperature minerals of the carbonaceous chondrites.

  17. Lunar Regolith Excavation Competition

    NASA Technical Reports Server (NTRS)

    Liles, Cassandra

    2009-01-01

    The Lunar Regolith Excavation Competition is a new competition that needs graphics, logos, rules, as well as an arena. Although this is the first year of the competition, the competition is modeled after an existing competition, the Centennial Lunar Excavator Challenge. This competition however is aimed at college students. This makes the challenge identifying key aspects of the original competition and modeling them to fit into an easier task, and creating exciting advertisement that helps encourage participation. By using a youth focus group, young insight, as well as guiding advice from experts in the field, hopefully an arena can be designed and built, rules can be molded and created to fit, and alluring graphics can be printed to bring about a successful first year of the Lunar Regolith Excavation Competition.

  18. The Scattering Properties of Natural Terrestrial Snows versus Icy Satellite Surfaces

    NASA Technical Reports Server (NTRS)

    Domingue, Deborah; Hartman, Beth; Verbiscer, Anne

    1997-01-01

    Our comparisons of the single particle scattering behavior of terrestrial snows and icy satellite regoliths to the laboratory particle scattering measurements of McGuire and Hapke demonstrate that the differences between icy satellite regoliths and their terrestrial counterparts are due to particle structures and textures. Terrestrial snow particle structures define a region in the single particle scattering function parameter space separate from the regions defined by the McGuire and Hapke artificial laboratory particles. The particle structures and textures of the grains composing icy satellites regoliths are not simple or uniform but consist of a variety of particle structure and texture types, some of which may be a combination of the particle types investigated by McGuire and Hapke.

  19. Recycled grains in lunar soils as an additional, necessary, regolith evolution parameter

    NASA Technical Reports Server (NTRS)

    Basu, A.

    1990-01-01

    Recycled lunar soil grains are defined as those soil grains that have been a part of either regolith breccias or agglutinates; thus, mineral grains, rock fragments, older agglutinates, and volcanic glass spherules, if dislodged from an agglutinate or a regolith breccia, would all qualify as recycled grains. This paper shows that it is possible to estimate the proportion of recycled material in lunar soils. Optical data from 12 soils in the Apollo 16 core 64001/2 were collected to estimate the proportion (W) of recycled crystalline grains in each of these soils. The W values show a correspondence with other independently derived parameters and the history of the core soils, indicating that W can be used as a valid soil-evolution parameter.

  20. Rayleigh Wave Ellipticity Modeling and Inversion for Shallow Structure at the Proposed InSight Landing Site in Elysium Planitia, Mars

    NASA Astrophysics Data System (ADS)

    Knapmeyer-Endrun, Brigitte; Golombek, Matthew P.; Ohrnberger, Matthias

    2017-10-01

    The SEIS (Seismic Experiment for Interior Structure) instrument onboard the InSight mission will be the first seismometer directly deployed on the surface of Mars. From studies on the Earth and the Moon, it is well known that site amplification in low-velocity sediments on top of more competent rocks has a strong influence on seismic signals, but can also be used to constrain the subsurface structure. Here we simulate ambient vibration wavefields in a model of the shallow sub-surface at the InSight landing site in Elysium Planitia and demonstrate how the high-frequency Rayleigh wave ellipticity can be extracted from these data and inverted for shallow structure. We find that, depending on model parameters, higher mode ellipticity information can be extracted from single-station data, which significantly reduces uncertainties in inversion. Though the data are most sensitive to properties of the upper-most layer and show a strong trade-off between layer depth and velocity, it is possible to estimate the velocity and thickness of the sub-regolith layer by using reasonable constraints on regolith properties. Model parameters are best constrained if either higher mode data can be used or additional constraints on regolith properties from seismic analysis of the hammer strokes of InSight's heat flow probe HP3 are available. In addition, the Rayleigh wave ellipticity can distinguish between models with a constant regolith velocity and models with a velocity increase in the regolith, information which is difficult to obtain otherwise.

  1. Volatile Analysis by Pyrolysis of Regolith (Vapor) on the Moon using Mass Spectrometry

    NASA Technical Reports Server (NTRS)

    Glavin, D. P.; Kate, I. L. ten; Brinckerhoff, W.; Cardiff, E.; Dworkin, J. P.; Feng, S.; Getty, S.; Gorevan, S.; Harpold, D.; Jones, A. L.; hide

    2008-01-01

    The identification of lunar resources such as water is a fundamental component of the the NASA Vision for Space Exploration. The Lunar Prospector mission detected high concentrations of hydrogen at the lunar poles that may indicate the presence of water or other volatiles in the lunar regolith [1]. One explanation for the presence of enhanced hydrogen in permanently shadowed crater regions is long term trapping of water-ice delivered by comets, asteroids, and other meteoritic material that have bombarded the Moon over the last 4 billion years [2]. It is also possible that the hydrogen signal at the lunar poles is due to hydrogen implanted by the solar wind which is delayed from diffusing out of the regolith by the cold temperatures [3]. Previous measurements of the lunar atmosphere by the LACE experiment on Apollo 17, suggested the presence of cold trapped vola'tiles that were expelled by solar heating [4]. In situ composition and isotopic analyses of the lunar regolith will be required to establish the abundance, origin, and distribution of water-ice and other volatiles at the lunar poles. Volatile Analysis by Pyrolysis of Regolith (VAPoR) on the Moon using mass spectrometry is one technique that should be considered. The VAPoR pyrolysis-mass spectrometer (pyr-MS) instrument concept study was selected for funding in 2007 by the NASA Lunar Sortie Science Opportunities (LSSO) Program. VAPoR is a miniature version of the Sample Analysis at Mars (SAM) instrument suite currently being developed at NASA Goddard for the 2009 Mars Science Laboratory mission (Fig. 1).

  2. Compositional Diversity of the Vestan Regolith Derived from Howardite Compositions and Dawn VIR Spectra

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, D. W.; Ammannito, E.; Hiroi, T.; DeAngeles, S.; Moriarty, D. P.; DiIorio, T.; Pieters, C. M.; DeSanctis, M. C.

    2014-01-01

    Howardite, eucrite and diogenite meteorites likely come from asteroid 4 Vesta [1]. Howardites - physical mixtures of eucrites and diogenites - are of two subtypes: regolithic howardites were gardened in the true regolith; fragmental howardites are simple polymict breccias [2]. The Dawn spacecraft imaged the howarditic surface of Vesta with the visible and infrared mapping spectrometer (VIR) resulting in qualitative maps of the distributions of distinct diogenite-rich and eucrite-rich terranes [3, 4]. We are developing a robust basis for quantitative mapping of the distribution of lithologic types using spectra acquired on splits of well-characterized howardites [5, 6]. Spectra were measured on sample powders sieved to <75 µm in the laboratories of the Istituto di Astrofisica e Planetologia Spaziali and Brown University. Data reduction was done using the methods developed to process Dawn VIR spectra [4]. The band parameters for the 1 and 2 µm pyroxene absorption features (hereafter BI and BII) can be directly compared to Dawn VIR results. Regolithic howardites have shallower BI and BII absorptions compared to fragmental howardites with similar compositions. However, there are statistically significant correlations between Al or Ca contents and BI or BII center wavelengths regardless of howardite subtype. Diogenites are poor in Al and Ca while eucrites are rich in these elements. The laboratory spectra can thus be directly correlated with the percentage of eucrite material contained in the howardites. We are using these correlations to quantitatively map Al and Ca distributions, and thus the percentage of eucritic material, in the current regolith of Vesta.

  3. Lunar surface mining for automated acquisition of helium-3: Methods, processes, and equipment

    NASA Technical Reports Server (NTRS)

    Li, Y. T.; Wittenberg, L. J.

    1992-01-01

    In this paper, several techniques considered for mining and processing the regolith on the lunar surface are presented. These techniques have been proposed and evaluated based primarily on the following criteria: (1) mining operations should be relatively simple; (2) procedures of mineral processing should be few and relatively easy; (3) transferring tonnages of regolith on the Moon should be minimized; (4) operations outside the lunar base should be readily automated; (5) all equipment should be maintainable; and (6) economic benefit should be sufficient for commercial exploitation. The economic benefits are not addressed in this paper; however, the energy benefits have been estimated to be between 250 and 350 times the mining energy. A mobile mining scheme is proposed that meets most of the mining objectives. This concept uses a bucket-wheel excavator for excavating the regolith, several mechanical electrostatic separators for beneficiation of the regolith, a fast-moving fluidized bed reactor to heat the particles, and a palladium diffuser to separate H2 from the other solar wind gases. At the final stage of the miner, the regolith 'tailings' are deposited directly into the ditch behind the miner and cylinders of the valuable solar wind gases are transported to a central gas processing facility. During the production of He-3, large quantities of valuable H2, H2O, CO, CO2, and N2 are produced for utilization at the lunar base. For larger production of He-3 the utilization of multiple-miners is recommended rather than increasing their size. Multiple miners permit operations at more sites and provide redundancy in case of equipment failure.

  4. Lunar surface mining for automated acquisition of helium-3: Methods, processes, and equipment

    NASA Astrophysics Data System (ADS)

    Li, Y. T.; Wittenberg, L. J.

    1992-09-01

    In this paper, several techniques considered for mining and processing the regolith on the lunar surface are presented. These techniques have been proposed and evaluated based primarily on the following criteria: (1) mining operations should be relatively simple; (2) procedures of mineral processing should be few and relatively easy; (3) transferring tonnages of regolith on the Moon should be minimized; (4) operations outside the lunar base should be readily automated; (5) all equipment should be maintainable; and (6) economic benefit should be sufficient for commercial exploitation. The economic benefits are not addressed in this paper; however, the energy benefits have been estimated to be between 250 and 350 times the mining energy. A mobile mining scheme is proposed that meets most of the mining objectives. This concept uses a bucket-wheel excavator for excavating the regolith, several mechanical electrostatic separators for beneficiation of the regolith, a fast-moving fluidized bed reactor to heat the particles, and a palladium diffuser to separate H2 from the other solar wind gases. At the final stage of the miner, the regolith 'tailings' are deposited directly into the ditch behind the miner and cylinders of the valuable solar wind gases are transported to a central gas processing facility. During the production of He-3, large quantities of valuable H2, H2O, CO, CO2, and N2 are produced for utilization at the lunar base. For larger production of He-3 the utilization of multiple-miners is recommended rather than increasing their size. Multiple miners permit operations at more sites and provide redundancy in case of equipment failure.

  5. How LEND sees the water on the Moon

    NASA Astrophysics Data System (ADS)

    Sanin, Anton; Mitrofanov, Igor; Litvak, Maxim; Boynton, William; Bodnarik, Julia; Hamara, Dave; Harshman, Karl; Chin, Gordon; Evans, Larry; Livengood, Timothy; McClanahan, Timothy; Sagdeev, Roald; Starr, Richard

    2016-04-01

    The Lunar Exploration Neutron Detector (LEND) is operating on orbit around the Moon on-board the Lunar Reconnaissance Orbiter (LRO) spacecraft more than six years. LEND has been designed and manufactured to investigate presence and determine average amount of hydrogen in upper (~1 m depth) subsurface layer of the Lunar regolith with spatial resolution ~10 km from 50 km orbit and to check the hypothesis what the permanently shadowed regions (PSRs) at circumpolar regions are the main reservoirs of a large deposition of water ice on the Moon. One of most interesting and surprising LEND observations that not all large PSRs contain a detectable amount of hydrogen but there are neutron suppression regions (NSRs) with statistically significant suppression of neutron flux. The NSRs partially overlap or include PSRs in craters Cabeus, Shoemaker, Haworth (on South) and Rozhdestvensky U (on North) but significant part of their area spread out at sunlit territory. This means that hydrogen may be preserved for a long time or even accumulated at a subsurface regolith layer of sunlit areas. The majority of PSRs do not show statistically significant suppressions of neutron flux in comparison with neighbor sunlit vicinity. This implies a hypothesis what a permanent shadow is not only necessary condition for the hydrogen accumulation and preservation in the lunar subsurface. A method of water equivalent hydrogen (WEH) in top ~1 meter regolith estimation using LEND data has been developed. Maps of WEH distribution in North and South polar regions will be presented and discussed. Also, WEH estimation in case of hydrogen bearing regolith layer coverage by a dry regolith will be presented for largest NSRs.

  6. Elements of Regolith Simulant's Cost Structure

    NASA Technical Reports Server (NTRS)

    Rickman, Douglas L.

    2009-01-01

    The cost of lunar regolith simulants is much higher than many users anticipate. After all, it is nothing more than broken rock. This class will discuss the elements which make up the cost structure for simulants. It will also consider which elements can be avoided under certain circumstances and which elements might be altered by the application of additional research and development.

  7. Distribution of Quercus agrifolia mycorrhizae deep within weathered bedrock: a potential mechanism for transport of stored water

    Treesearch

    M. Bornyasz; R. Graham; M. Allen

    2002-01-01

    In southwestern California, Quercus agrifolia distribution closely matches regions of granitic regolith. High annual evapotranspiration demand and inherent shallow soil conditions lead to a dependence on a deep rooting system and an ability to access water from deep within the regolith. Most of the plant available water in weathered granitic rock is...

  8. RESOLVE: Regolith and Environment Science and Oxygen and Lunar Volatile Extraction

    NASA Technical Reports Server (NTRS)

    Quinn, Jacqueline; Baird, Scott; Colaprete, Anthony; Larson, William; Sanders, Gerald; Picard, Martin

    2011-01-01

    Regolith & Environment Science and Oxygen & Lunar Volatile Extraction (RESOLVE) is an internationally developed payload that is intended to prospect for resources on other planetary bodies. RESOLVE is a miniature drilling and chemistry plant packaged onto a medium-sized rover to collect and analyze soil for volatile components such as water or hydrogen that could be used in human exploration efforts.

  9. Primary sedimentary structures and the internal architecture of a Martian sand body in search of evidence for sand transport and deposition

    NASA Technical Reports Server (NTRS)

    Basu, Abhijit

    1988-01-01

    Lunar experiences show that unmanned sample return missions, despite limitations on sample size, can produce invaluable data to infer crustal processes, regolith processes, regolith-atmosphere/ionosphere interaction processes, etc. Drill cores provide a record of regolith evolution as well as a more complete sample of the regolith than small scoops and/or rakes. It is proposed that: (1) a hole be drilled in a sand body to obtain continuous oriented cores; a depth of about 10 m would be compatible with what we know of bed form hierarchy of terrestrial stream deposits; (2) two trenches, at right angles to each other and close to the drill-hole, be dug and the walls scraped lightly such that primary/internal sedimentary structures of the sand body become visible; (3) the walls of the trenches be made gravitationally stable by impregnation techniques; (4) acetate or other peels of a strip on each wall be taken; and (5) appropriately scaled photographs of the walls be taken at different sun-angles to ensure maximum ease of interpretation of sedimentary structures; and, to correlate these structural features with those in the core at different depth levels of the core.

  10. Solar Concentrator Demonstrator for Lunar Regolith Processing

    NASA Technical Reports Server (NTRS)

    Fikes, John C.; Howell, Joe T.; Gerrish, Harold P.; Patrick, Stephen L.

    2008-01-01

    NASA at the Marshall Space Flight Center (MSFC) is building a portable inflatable solar concentrator ground demonstrator for use in testing in-situ resource utilization (ISRU) lunar regolith processing methods. Of primary interest is the production of oxygen as a propellant oxidizer and for life support. There are various processes being proposed for the in-situ reduction of the lunar regolith, the leading processes are hydrogen reduction, carbothermal reduction and vapor phase pyrolysis. The concentrator system being built at MSFC could support demonstrations of all of these processes. The system consists of a light inflatable concentrator that will capture sunlight and focus it onto a receiver inside a vacuum chamber. Inflatable concentrators are good for space based applications due to their low weight and dense packaging at launch. The hexapod design allows the spot size to be increased to reduce the power density if needed for the process being demonstrated. In addition to the hardware development, a comprehensive simulation model is being developed and will be verified and validated using the system hardware. The model will allow for the evaluation of different lunar locations and operational scenarios for the lunar regolith processing with a high confidence in the predicted results.

  11. Plasma Processing of Lunar Regolith Simulant for Diverse Applications

    NASA Technical Reports Server (NTRS)

    Schofield, Elizabeth C.; Sen, Subhayu; O'Dell, J. Scott

    2008-01-01

    Versatile manufacturing technologies for extracting resources from the moon are needed to support future space missions. Of particular interest is the production of gases and metals from lunar resources for life support, propulsion, and in-space fabrication. Deposits made from lunar regolith could yield highly emissive coatings and near-net shaped parts for replacement or repair of critical components. Equally important is development of high fidelity lunar simulants for ground based validation of potential lunar surface operations. Described herein is an innovative plasma processing technique for insitu production of gases, metals, coatings, and deposits from lunar regolith, and synthesis of high fidelity lunar simulant from NASA issued lunar simulant JSC-1. Initial plasma reduction trials of JSC-1 lunar simulant have indicated production of metallic iron and magnesium. Evolution of carbon monoxide has been detected subsequent to reduction of the simulant using the plasma process. Plasma processing of the simulant has also resulted in glassy phases resembling the volcanic glass and agglutinates found in lunar regolith. Complete and partial glassy phase deposits have been obtained by varying the plasma process variables. Experimental techniques, product characterization, and process gas analysis will be discussed.

  12. Towards Calibrating the Vestan Regolith: Correlating the Petrology, Chemistry and Spectroscopy of Howardites

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, D. W.; Ammannito, E.; Hiroi, T.; De Angelis, S.; Di Iorio, T.; Pieters, C. M.; De Sanctis, C.

    2013-01-01

    The Dawn spacecraft carries a visible and infrared mapping spectrometer (VIR) [1] that has acquired spectra for the wavelength range 0.25-5.0 µm at various spatial resolutions covering much of the vestan surface [2]. Through comparison of VIR spectra with laboratory spectra of howardite, eucrite and diogenite meteorites, the distribution of more diogenite-rich and more eucrite-rich terranes on Vesta have been mapped [3], but these maps are qualitative in nature. The available laboratory spectra are not well-integrated with detailed sample petrology or composition limiting their utility for lithologic mapping. Importantly, howardites are now recognized to come in two subtypes, regolithic and fragmental [4]. The former are breccias assembled in part from true regolith, while the latter have had much less exposure to the space environment. We are attempting to develop a more quantitative basis for mapping the distribution of lithologic types on Vesta through acquiring laboratory spectra on splits of howardites that have been petrologically and chemically characterized [5]. Noble gas analyses have been done on some allowing identification of those howardites that have been exposed in the true regolith of Vesta [6].

  13. Lunar material resources: An overview

    NASA Technical Reports Server (NTRS)

    Carter, James L.

    1992-01-01

    The analysis of returned lunar samples and a comparison of the physical and chemical processes operating on the Moon and on the Earth provide a basis for predicting both the possible types of material resources (especially minerals and rocks) and the physical characteristics of ore deposits potentially available on the Moon. The lack of free water on the Moon eliminates the classes of ore deposits that are most exploitable on Earth; namely, (1) hydrothermal, (2) secondary mobilization and enrichment, (3) precipitation from a body of water, and (4) placer. The types of lunar materials available for exploitation are whole rocks and their contained minerals, regolith, fumarolic and vapor deposits, and nonlunar materials, including solar wind implantations. Early exploitation of lunar material resources will be primarily the use of regolith materials for bulk shielding; the extraction from regolith fines of igneous minerals such as plagioclase feldspars and ilmenite for the production of oxygen, structural metals, and water; and possibly the separation from regolith fines of solar-wind-implanted volatiles. The only element, compound, or mineral, that by itself has been identified as having the economic potential for mining, processing, and return to Earth is helium-3.

  14. New Fiber Reinforced Waterless Concrete for Extraterrestrial Structural Applications

    NASA Technical Reports Server (NTRS)

    Toutanji, H.; Tucker, D.; Ethridge, E.

    2005-01-01

    Commercial use of sulfur concrete on Earth is well established, particularly in corrosive, e.g., acid and salt, environments. Having found troilite (FeS) on the Moon raises the question of using extracted sulfur as a lunar construction mate: iii an attractive alternative to conventional concrete as it does not require water For the purpose of this paper it is assumed that lunar ore is mined, refined, and the raw sulfur processed with appropriate lunar regolith to form, for example, brick and beam elements. Glass fibers produced from regolith were used as a reinforcement to improve the mechanical properties of the sulfur concrete. Glass fibers and glass rebar were produced by melting the lunar regolith simulant. Lunar regolith stimulant was melted in a 25 cc Pt-Rh crucible in a Sybron Thermoline 46100 high temperature MoSi2 furnace at melting temperatures of 1450 to 1600G. The glass melt wets the ceramic rod and long continuous glass fibers were easily hand drawn. The glass fibers were immediately coated with a protective polymer to maintain the mechanical strength. The viability of sulfur concrete as a construction material for extraterrestrial application is presented. The mechanical properties of the glass fiber reinforced sulfur concrete were investigated.

  15. A One-Piece Lunar Regolith Bag Garage Prototype

    NASA Technical Reports Server (NTRS)

    Smithers, G. A.; Nehls, M. K.; Hovater, M. A.; Evans, S. W.; Miller, J. S.; Broughton, R. M., Jr.; Beale, D.; Kilinc-Balci, F.

    2007-01-01

    Shelter structures on the moon, even in early phases of exploration, should incorporate lunar materials as much as possible. This Technical Memorandum details the design and construction of a prototype for a one-piece regolith bag unpressurized garage concept and a materials testing program to investigate six candidate fabrics to learn how they might perform in the lunar environment. The conceptualization was that a lightweight fabric form be launched from Earth and landed on the lunar surface to be robotically filled with raw lunar regolith. Regolith bag fabric candidates included: Vectran(TM), Nextel(TM), Gore PTFE Fabric(TM), Zylon(TM), Twaron(TM), and Nomex(TM). Tensile (including post radiation exposure), fold, abrasion, and hypervelocity impact testing were performed under ambient conditions, and also performed under cold and elevated temperatures. In some cases, Johnson Space Center lunar simulant (JSC-1) was used in conjunction with testing. A series of preliminary structures was constructed during final prototype design based on the principles of the classic masonry arch. The prototype was constructed of Kevlar(TM) and filled with vermiculite. The structure is free-standing, but has not yet been load tested. Future plans would be to construct higher fidelity prototypes and to conduct appropriate tests of the structure.

  16. Telerobotic Perception During Asteroid and Mars Regolith Operations Project

    NASA Technical Reports Server (NTRS)

    Gaddis, Steven; Zeitlin, Nancy (Compiler); Mueller, Robert (Compiler)

    2015-01-01

    Current space telerobotic systems are constrained to only operating in bright light and dust-free conditions. This project will study the effects of difficult lighting and dust conditions on telerobotic perception systems to better assess and refine regolith operations on other neighboring celestial bodies. In partnership with Embry-Riddle Aeronautical University and Caterpillar, Inc., optical, LiDAR and RADAR sensing equipment will be used in performing the study. This project will create a known dust environment in the Swamp Works Granular Mechanics & Regolith Operations (GMRO) Laboratory regolith test bin to characterize the behavior of the sensing equipment in various calibrated lighting and dust conditions. It will also identify potential methods for mitigating the impacts of these undesirable conditions on the performance of the sensing equipment. Enhancing the capability of telerobotic perception systems will help improve life on earth for those working in dangerous, dusty mining conditions, as well as help advance the same technologies used for safer self-driving automobiles in various lighting and weather conditions. It will also prove to be a critical skill needed for advancing robotic and human exploration throughout our solar system, for activities such as mining on an asteroid or pioneering the first colony on Mars.

  17. Standard Lunar Regolith Simulants for Space Resource Utilization Technologies Development: Effects of Materials Choices

    NASA Technical Reports Server (NTRS)

    Sibille, Laurent; Carpenter, Paul K.

    2006-01-01

    As NASA turns its exploration ambitions towards the Moon once again, the research and development of new technologies for lunar operations face the challenge of meeting the milestones of a fastpace schedule, reminiscent of the 1960's Apollo program. While the lunar samples returned by the Apollo and Luna missions have revealed much about the Moon, these priceless materials exist in too scarce quantities to be used for technology development and testing. The need for mineral materials chosen to simulate the characteristics of lunar regoliths is a pressing issue that is being addressed today through the collaboration of scientists, engineers and NASA program managers. The issue of reproducing the properties of lunar regolith for research and technology development purposes was addressed by the recently held 2005 Workshop on Lunar Regolith Simulant Materials at Marshall Space Flight Center. The recommendation of the workshop of establishing standard simulant materials to be used in lunar technology development and testing will be discussed here with an emphasis on space resource utilization. The variety of techniques and the complexity of functional interfaces make these simulant choices critical in space resource utilization.

  18. Early Energetic Particle Irradiation of the HED Parent Body Regolith

    NASA Technical Reports Server (NTRS)

    Bogard, D. D.; Garrison, D. H.; Rao, M. N.

    1996-01-01

    Previous studies have shown that many individual grains within the dark phase of the Kapoeta howardite were irradiated with energetic particles while residing on the surface of the early HED regolith. Particle tracks in these grains vary in density by more than an order of magnitude and undoubtedly were formed by energetic heavy (Fe) ions associated with early solar flares. Early Irradiation of HED Regolith: Concentrations of excess Ne alone are not sufficient to decide between competing galactic and solar irradiation models. However, from recent studies of depth samples of oriented lunar rocks, we have shown that the cosmogenic 21-Ne/22-Ne ratio produced in feldspar differs substantially between Galactic Cosmic Radiation (GCR) and solar protons, and that this difference is exactly that predicted from cross-section data. Using Ne literature data and new isotopic data we obtained on acid-etched, separated feldspar from both the light and dark phases of Kapoeta, we derive 21-Ne/22-Ne = 0.80 for the recent GCR irradiation and 21-Ne/22-Ne = 0.68 for the early regolith irradiation. This derived ratio indicates that the early Ne production in the regolith occurred by both galactic and solar protons. If we adopt a likely one-component regolith model in which all grains were exposed to galactic protons but individual grains had variable exposure to solar protons, we estimate that this early GCR irradiation lasted for about 3-6 m.y. More complex two-component regolith models involving separate solar and galactic irradiation would permit this GCR age to be longer. Higher-energy solar protons would permit the GCR to be longer. Higher-energy solar protons would permit the GCR age to be shorter. Further, cosmogenic 126(Xe) in Kapoeta dark is no more than a factor of about 2 higher than that observed in Kapoeta light. Because 126(Xe) can only be formed by galactic protons and not solar protons, these data support a short GCR irradiation for the HED regolith. This would also be the maximum time peRiod for the solar irradiation. Various asteroidal regolith models, based on Monte Carlo modeling of impact rates as a function of size and on irradiation features of meteorites, predict surface exposure times of about 0.1 to 10 m.y., and depend on such factors as gravity, rock mechanical properties, and micrometeoroid flux. Because the depth at which solar Fe tracks are produced (is much less than 1 micrometer) is much less than the depth at which Solar Cosmic Rays (SCR) Ne is produced (about 1 cm), for a reasonably well-stirred HED regolith the "surface exposure time" for SCR 21-Ne production should be significantly longer than that for solar tracks and some other surface irradiation features. Enhanced Solar Proton Irradiation: For bulk samples of Kapoeta dark feldspar and a one-component regolith model, the derived ratio of 21-Ne/22-Ne = 0.68 implies that the early production ratio of SCR 21-Ne to GCR 21-Ne was about 0.5-1.5. This ratio is independent of any assumptions about the fraction of dark grains that are irradiated or of the variability in the degree of solar irradiation among grains. The 21-Ne SCR/GCR ratio indirectly derived from bulk Kapoeta pyroxene is somewhat larger, as is the ratio derived for simple two-component regolith models. Individual feldspar grains that were extensively solar irradiated would require even larger 21-Ne SCR/GCR production ratios. In contrast, the theoretical SCR/GCR production ratio for lunar feldspar with 0 g/CM2 shield ing is is less than or equal to 2, and the lowest ratio observed in near-surface samples of lunar anorthosites is less than or equal to 1. Considering the greater solar distance of Vesta (compared to the Moon), the likelihood that SCR 21-Ne was acquired under some shielding where production rates are lower, and the likelihood that the exposure time to galactic protons exceeded the exposure time to solar protons because of their very different penetration depths, the 21-Ne SCR/GCR production ratio on the HED parent body was probably < 0.1. The relatively large difference between the derived 21-Ne SCR/GCR ratio in Kapoeta dark feldspar and the estimated production ratio strongly indicates that the early solar irradiation involved a flux -20-50x the recent solar flux. This enhanced proton flux was probably associated with an overall greater solar activity in the first approximately 10(exp 7) to 10(exp 8) years of solar history.

  19. Magnetosphere-Regolith/Exosphere Coupling: Differences and Similarities to the Earth Magnetosphere-Ionosphere Coupling

    NASA Technical Reports Server (NTRS)

    Gjerleov, J. W.; Slavin, J. A.

    2001-01-01

    Of the three Mercury passes made by Mariner 10, the first and third went through the Mercury magnetosphere. The third encounter which occurred during northward IMF (interplanetary magnetic field) showed quiet time magnetic fields. In contrast the third encounter observed clear substorm signatures including dipolarization, field-aligned currents (FACs) and injection of energetic electrons at geosynchronous orbit. However, the determined cross-tail potential drop and the assumed height integrated conductance indicate that the FAC should be 2-50 times weaker than observed. We address this inconsistency and the fundamental problem of FAC closure whether this takes place in the regolith or in the exosphere. The current state of knowledge of the magnetosphere-exosphere/regolith coupling is addressed and similarities and differences to the Earth magnetosphere-ionosphere coupling are discussed.

  20. Compositional characteristics of some Apollo 14 clastic materials.

    NASA Technical Reports Server (NTRS)

    Lindstrom, M. M.; Duncan, A. R.; Fruchter, J. S.; Mckay, S. M.; Stoeser, J. W.; Goles, G. G.; Lindstrom, D. J.

    1972-01-01

    Eighty-two subsamples of Apollo 14 materials have been analyzed by instrumental neutron activation analysis techniques for as many as 25 elements. In many cases, it was necessary to develop new procedures to allow analyses of small specimens. Compositional relationships among Apollo 14 materials indicate that there are small but systematic differences between regolith from the valley terrain and that from Cone Crater ejecta. Fragments from 1-2 mm size fractions of regolith samples may be divided into compositional classes, and the 'soil breccias' among them are very similar to valley soils. Multicomponent linear mixing models have been used as interpretive tools in dealing with data on regolith fractions and subsamples from breccia 14321. These mixing models show systematic compositional variations with inferred age for Apollo 14 clastic materials.

  1. A coupled subsurface-boundary layer model of water on Mars

    NASA Astrophysics Data System (ADS)

    Zent, A. P.; Haberle, R. M.; Houben, H. C.; Jakosky, B. M.

    1993-02-01

    A 1D numerical model of the exchange of H2O between the atmosphere and subsurface of Mars through the PBL is employed to explore the mechanisms of H2O exchange and to elucidate the role played by the regolith in the local H2O budget. The atmospheric model includes effects of Coriolis, pressure gradient, and frictional forces for momentum: radiation, sensible heat flux, and advection for heat. It is suggested that in most cases, the flux through the Martian surface reverses twice in the course of each sol. The effects of surface albedo, thermal inertia, solar declination, atmospheric optical depth, and regolith pore structure are explored. It is proposed that higher thermal inertia forces more H2O into the atmosphere because the regolith is warmer at depth.

  2. Joule-Heated Molten Regolith Electrolysis Reactor Concepts for Oxygen and Metals Production on the Moon and Mars

    NASA Technical Reports Server (NTRS)

    Sibille, Laurent; Dominguez, Jesus A.

    2012-01-01

    The technology of direct electrolysis of molten lunar regolith to produce oxygen and molten metal alloys has progressed greatly in the last few years. The development of long-lasting inert anodes and cathode designs as well as techniques for the removal of molten products from the reactor has been demonstrated. The containment of chemically aggressive oxide and metal melts is very difficult at the operating temperatures ca. 1600 C. Containing the molten oxides in a regolith shell can solve this technical issue and can be achieved by designing a Joule-heated (sometimes called 'self-heating') reactor in which the electrolytic currents generate enough Joule heat to create a molten bath. Solutions obtained by multiphysics modeling allow the identification of the critical dimensions of concept reactors.

  3. Electrical stress and strain in lunar regolith simulants

    NASA Astrophysics Data System (ADS)

    Marshall, J.; Richard, D.; Davis, S.

    2011-11-01

    Experiments to entrain dust with electrostatic and fluid-dynamic forces result in particulate clouds of aggregates rather than individual dust grains. This is explained within the framework of Griffith-flaw theory regarding the comminution/breakage of weak solids. Physical and electrical inhomogeneities in powders are equivalent to microcracks in solids insofar as they facilitate failure at stress risers. Electrical charging of powders induces bulk sample stresses similar to mechanical stresses experienced by strong solids, depending on the nature of the charging. A powder mass therefore "breaks" into clumps rather than separating into individual dust particles. This contrasts with the expectation that electrical forces on the Moon will eject a submicron population of dust from the regolith into the exosphere. A lunar regolith will contain physical and electrostatic inhomogeneities similar to those in most charged powders.

  4. Development Issues for Lunar Regolith Simulants

    NASA Technical Reports Server (NTRS)

    Rickman, Doug; Carpenter, Paul; Sibille, Laurent; Owens, Charles; French, Raymond; McLemore, Carole

    2006-01-01

    Significant challenges and logistical issues exist for the development of standardized lunar regolith simulant (SLRS) materials for use in the development and testing of flight hardware for upcoming NASA lunar missions. A production program at Marshall Space Flight Center (MSFC) for the deployment of lunar mare basalt simulant JSC-lA is underway. Root simulants have been proposed for the development of a low-T mare basalt simulant and a high-Ca highland anorthosite simulant, as part of a framework of simulant development outlined in the 2005 Lunar Regolith Simulant Materials Workshop held at MSFC. Many of the recommendation for production and standardization of simulants have already been documented by the MSFC team. But there are a number of unanswered questions related to geology which need ta be addressed prior to the creation of the simulants.

  5. C Chondrite Clasts in H Chondrite Regolith Breccias: Something Different

    NASA Technical Reports Server (NTRS)

    Zolensky, M. E.; Fries, M.; Utas, J.; Chan, Q. H.-S.; Kebukawa, Y.; Steele, A.; Bodnar, R. J.; Ito, M.; Nakashima, D.; Greenwood, R.; hide

    2016-01-01

    Zag (H3-6) and Monahans (1998) (H5) are regolith breccias that contain 4.5 GY old halite crystals which in turn contain abundant inclusions of aqueous fluids, solids and organics [1-4]. We have previously proposed that these halites originated on a hydro-volcanically-active C-class asteroid, probably Ceres [3-7]. We have begun a detailed analysis of the included solids and organics and are re-examining the related carbonaceous (C)) chondrite clast we previously reported in Zag [5-7]. These new investigations will potentially reveal the mineralogy of asteroid Ceres. We report here on potentially identical C chondrite clasts in the H chondrite regolith breccias Tsukuba (H5-6) and Carancas (H4-5). The clast in Tsukuba was known before [8], but the Carancas clast is newly recognized.

  6. A Future Moon Mission: Curatorial Statistics on Regolith Fragments Applicable to Sample Collection by Raking

    NASA Technical Reports Server (NTRS)

    Allton, J. H.; Bevill, T. J.

    2003-01-01

    The strategy of raking rock fragments from the lunar regolith as a means of acquiring representative samples has wide support due to science return, spacecraft simplicity (reliability) and economy [3, 4, 5]. While there exists widespread agreement that raking or sieving the bulk regolith is good strategy, there is lively discussion about the minimum sample size. Advocates of consor-tium studies desire fragments large enough to support petrologic and isotopic studies. Fragments from 5 to 10 mm are thought adequate [4, 5]. Yet, Jolliff et al. [6] demonstrated use of 2-4 mm fragments as repre-sentative of larger rocks. Here we make use of cura-torial records and sample catalogs to give a different perspective on minimum sample size for a robotic sample collector.

  7. Oxygen Production from Lunar Regolith using Ionic Liquids

    NASA Technical Reports Server (NTRS)

    Paley, Mark Steven; Karr, Laurel J.; Curreri, Peter

    2009-01-01

    The objective of this work and future follow-on work is to develop a safe, efficient, and recyclable method for oxygen and/or metals extraction from lunar regolith, in support of establishing a manned lunar outpost. The approach is to solubilize the oxides that comprise lunar regolith in media consisting of ionic liquids (ILs) and/or their mixtures at temperatures at or below 300 C. Once in solution, electrolysis can either be performed in-situ to generate oxygen at the anode and hydrogen and/or metals (silicon, iron, aluminum, titanium, etc.) at the cathode. Alternatively, the water that is generated during the solubilization process can be distilled out and condensed into a separate IL and then electrolysized to produce hydrogen and oxygen. In the case of lunar regolith, this method could theoretically produce 44g oxygen per 100g of regolith. The oxygen can be used for human life support and/or as an oxidizer for rocket fuels, and the metals can be used as raw materials for construction and/or device fabrication. Moreover, the hydrogen produced can be used to re-generate the acidic medium, which can then be used to process additional regolith, thereby making the materials recyclable and limiting upmass requirements. An important advantage of IL acid systems is that they are much "greener" and safer than conventional materials used for regolith processing such as sulfuric or hydrochloric acids. They have very low vapor pressures, which means that they contain virtually no toxic and/or flammable volatile content, they are relatively non-corrosive, and they can exhibit good stability in harsh environments (extreme temperatures, hard vacuum, etc.). Furthermore, regolith processing can be achieved at lower temperatures than other processes such as molten oxide electrolysis or hydrogen reduction, thereby reducing initial power requirements. Six ILs have been synthesized and tested for their capability to dissolve lunar simulant, and for electrochemical and thermal stability. The results showed that ILs can be very efficient electrolytes; in particular IL/phosphoric-acid mixtures appear extremely promising for solubilizing lunar simulant. Results from preliminary experiments for distillation of water produced from the oxygen within the metal oxides of the simulant and the hydrogen from the acid indicates that over 75% of the oxygen from the simulant can be harvested as water at a temperature of 150 C. A method for collection of oxygen from electrolysis of the water derived from solubilizing simulant was developed by using a liquid nitrogen trap to liquefy and collect the oxygen. Although precise quantification of the liquid oxygen trapped is difficult to obtain, the amount of hydrogen and oxygen collected from electrolysis of water in this system was greater than 98%. This set-up also included a portable mass spectrometer for the identification of gases released from electrolysis cells. Regeneration of ILs through re-protonation was also demonstrated. Four sequential re-generations of an IL following solubilization of simulant showed no significant differences in amounts of simulant dissolved. Follow-on work for this project should include more studies of IL/phosphoric acid systems. Also, much more work is necessary for defining methods for electrolysis and purification of metals from regolith solubilized in ILs, and for developing a system to use the produced hydrogen to regenerate the spent IL. Finally, design and development of flight breadboard and prototype hardware is required.

  8. Space weathering of silicate regoliths with various FeO contents: New insights from laser irradiation experiments and theoretical spectral simulations

    NASA Astrophysics Data System (ADS)

    Moroz, Lyuba V.; Starukhina, Larissa V.; Rout, Surya Snata; Sasaki, Sho; Helbert, Jörn; Baither, Dietmar; Bischoff, Addi; Hiesinger, Harald

    2014-06-01

    To investigate effects of micrometeorite bombardment on optical spectra and composition of planetary and asteroid regoliths with low Fe contents, we irradiated samples of a Fe-poor plagioclase feldspar (andesine-labradorite) using a nanosecond pulsed laser. We measured reflectance spectra of irradiated and non-irradiated areas of the samples (pressed pellets) between 0.5 and 18 μm and performed SEM/EDS and TEM studies of the samples. Bulk FeO content of 0.72 wt.% in the samples is comparable, for example, to FeO content in silicates on the surface of Mercury, that was recently mapped by NASA's MESSENGER mission and will be spectrally mapped by remote sensing instruments MERTIS and SYMBIO-SYS on board the ESA BepiColombo spacecraft. We also employed theoretical spectral modeling to characterize optical alteration caused by formation of nano- and submicrometer Fe0 inclusions within space-weathered surface layers and grain rims of a Fe-poor regolith. The laser-irradiated surface layer of plagioclase reveals significant melting, while reflectance spectra show mild darkening and reddening in the visible and near-infrared (VNIR). Our spectral modeling indicates that the optical changes observed in the visible require reduction of bulk FeO (including Fe from mineral impurities found in the sample) and formation of nanophase (np) Fe0 within the glassy surface layer. A vapor deposit, if present, is optically too thin to contribute to optical modification of the investigated samples or to cause space weathering-induced optical alteration of Fe-poor regoliths in general. Due to low thickness of vapor deposits, npFe0 formation in the latter can cause darkening and reddening only for a regolith with rather high bulk Fe content. Our calculations show that only a fraction of bulk Fe is likely to be converted to npFe0 in nanosecond laser irradiation experiments and probably in natural regolith layers modified by space weathering. The previously reported differences in response of different minerals to laser irradiation, and probably to space weathering-induced heating are likely controlled by their differences in electrical conductivities and melting points. For a given mineral grain, its susceptibility to melting/vaporization is also affected by electric conductivities of adjacent grains of other minerals in the regolith. Published nanosecond laser irradiation experiments simulate optical alteration of immature regoliths, since only the uppermost surface layer of an irradiated pellet is subject to heating. According to our calculations, if regolith particles due to impact-induced turnover are mantled with npFe0-bearing rims of the same thickness, then even low contents of Fe similar to our sample or Mercury' surface can cause significant darkening and reddening, provided a melt layer, rather than a thin vapor deposit is involved into npFe0 formation. All spectral effects observed in the thermal infrared (TIR) after irradiation of our feldspar sample are likely to be associated with textural changes. We expect that mineralogical interpretation of the BepiColombo MERTIS infrared spectra of Mercury between 7 and 17 μm will be influenced mostly by textural effects (porosity, comminution) and impact glass formation rather than formation of npFe0 inclusions.

  9. The preservation of ancient solar wind particles buried beneath lunar basalt flows as determined through heat transfer modeling

    NASA Astrophysics Data System (ADS)

    Rumpf, M. E.; Fagents, S. A.; Crawford, I. A.; Joy, K. H.

    2009-12-01

    The ever-changing environment on the Earth’s surface has erased any record of the early solar system. However, the antiquity of lunar surface combined with its negligible atmosphere and magnetosphere would have created conditions favorable for the preservation of ancient solar wind particles, galactic cosmic ray particles, and material that originated on other bodies in the inner solar system. Ancient particles emplaced in the regolith and subsequently buried beneath mare lava flows may have been preserved from subsequent bombardment provided the volatiles survived heat introduced by the lava flow. Discovery and extraction of such particles will aid in the advancement of several current solar system exploration goals, including studying the record of solar wind gases and investigating ancient atmospheric compositions on Earth and other inner planets. It has been shown that different volatile species will be released from the regolith when heated to specific temperature ranges between 573 and 973 K. We have developed a finite-volume numerical model that simulates heat transfer between a mare lava flow and the underlying regolith, to predict the preservation potential of ancient particles within layered deposits in the lunar maria. Results show that a 1 m thick basalt flow initially at 1500 K will heat an underlying regolith deposit to release implanted volatile species buried to a depth of 3.7 to 28 cm beneath the regolith surface; pristine samples would be preserved beneath these depths. At the estimated regolith formation rate of ~5 mm/Ma during the peak of mare volcanism (~3.6-3.8 Ga), an exposure time exceeding 7.4 to 56 Ma would be required prior to burial by the ensuing lava flow. Heating depths and required regolith formation times scale in direct proportion to the thickness of the overlying flow. Emplacement of multiple flow units over several hundred Ma would create intercalated stacks of lavas and regolith units, which could be radiometrically dated to provide a time series of the variability in intensity and composition of the solar wind. Suitable locations include Oceanus Procellarum, which contains numerous lava units ranging in age from 3.5-1.2 Ga. Extraction of implanted volatiles of a range of ages would require drilling through perhaps tens of meters of flow units and intervening paleoregoliths, which in turn indicates the need for tens to hundreds of km surface mobility and the provision for adequate sample collection and return. Detection of suitable paleoregolith deposits would be aided by tools such as ground penetrating radar. Although it may be argued that long-range robotic rover and sample return missions could tackle this objective, we propose that the complexity of the task is most readily addressed by a sortie-class human expedition to key sites in the lunar maria.

  10. System of extraction of volatiles from soil using microwave processes

    NASA Technical Reports Server (NTRS)

    Ethridge, Edwin C. (Inventor); Kaukler, William F. (Inventor)

    2013-01-01

    A device for the extraction and collection of volatiles from soil or planetary regolith. The device utilizes core drilled holes to gain access to underlying volatiles below the surface. Microwave energy beamed into the holes penetrates through the soil or regolith to heat it, and thereby produces vapor by sublimation. The device confines and transports volatiles to a cold trap for collection.

  11. Elements of Regolith Simulant's Cost Structure--Why Rock Is NOT Cheap

    NASA Technical Reports Server (NTRS)

    Rickman, Douglas L.

    2009-01-01

    The cost of lunar regolith simulants is much higher than many users anticipate. After all, it is nothing more than broken rock. This class will discuss the elements which make up the cost structure for simulants. It will also consider which elements can be avoided under certain circumstances and which elements might be altered by the application of additional research and development.

  12. Moonshine: Diurnally varying hydration through natural distillation on the Moon, detected by the Lunar Exploration Neutron Detector (LEND).

    PubMed

    Livengood, T A; Chin, G; Sagdeev, R Z; Mitrofanov, I G; Boynton, W V; Evans, L G; Litvak, M L; McClanahan, T P; Sanin, A B; Starr, R D; Su, J J

    2015-07-15

    The Lunar Exploration Neutron Detector (LEND), on the polar-orbiting Lunar Reconnaissance Orbiter (LRO) spacecraft, has detected suppression in the Moon's naturally-occurring epithermal neutron leakage flux that is consistent with the presence of diurnally varying quantities of hydrogen in the regolith near the equator. Peak hydrogen concentration (neutron flux suppression) is on the dayside of the dawn terminator and diminishes through the dawn-to-noon sector. The minimum concentration of hydrogen is in the late afternoon and dusk sector. The chemical form of hydrogen is not determinable from these measurements, but other remote sensing methods and anticipated elemental availability suggest water molecules or hydroxyl ions. Signal-to-noise ratio at maximum contrast is 5.6 σ in each of two detector systems. Volatiles are deduced to collect in or on the cold nightside surface and distill out of the regolith after dawn as rotation exposes the surface to sunlight. Liberated volatiles migrate away from the warm subsolar region toward the nearby cold nightside surface beyond the terminator, resulting in maximum concentration at the dawn terminator. The peak concentration within the upper ~1 m of regolith is estimated to be 0.0125 ± 0.0022 weight-percent water-equivalent hydrogen (wt% WEH) at dawn, yielding an accumulation of 190 ± 30 ml recoverable water per square meter of regolith at each dawn. Volatile transport over the lunar surface in opposition to the Moon's rotation exposes molecules to solar ultraviolet radiation. The short lifetime against photolysis and permanent loss of hydrogen from the Moon requires a resupply rate that greatly exceeds anticipated delivery of hydrogen by solar wind implantation or by meteoroid impacts, suggesting that the surface inventory must be continually resupplied by release from a deep volatile inventory in the Moon. The natural distillation of water from the regolith by sunlight and its capture on the cold night surface may provide energy-efficient access to volatiles for in situ resource utilization (ISRU) by direct capture before volatiles can enter the surface, eliminating the need to actively mine regolith for volatile resource recovery.

  13. Analysis of Lunar Highland Regolith Samples from Apollo 16 Drive Core 64001/2 and Lunar Regolith Simulants - An Expanding Comparative Database

    NASA Technical Reports Server (NTRS)

    Schrader, Christian M.; Rickman, Doug; Stoeser, Doug; Wentworth, Susan J.; Botha, Pieter WSK; Butcher, Alan R.; McKay, David; Horsch, Hanna; Benedictus, Aukje; Gottlieb, Paul

    2008-01-01

    We present modal data from QEMSCAN(registered TradeMark) beam analysis of Apollo 16 samples from drive core 64001/2. The analyzed lunar samples are thin sections 64002,6019 (5.0-8.0 cm depth) and 64001,6031 (50.0-53.1 cm depth) and sieved grain mounts 64002,262 and 64001,374 from depths corresponding to the thin sections, respectively. We also analyzed lunar highland regolith simulants NU-LHT-1M, -2M, and OB-1, low-Ti mare simulants JSC-1, -lA, -1AF, and FJS-1, and high-Ti mare simulant MLS-1. The preliminary results comprise the beginning of an internally consistent database of lunar regolith and regolith simulant mineral and glass information. This database, combined with previous and concurrent studies on phase chemistry, bulk chemistry, and with data on particle shape and size distribution, will serve to guide lunar scientists and engineers in choosing simulants for their applications. These results are modal% by phase rather than by particle type, so they are not directly comparable to most previously published lunar data that report lithic fragments, monomineralic particles, agglutinates, etc. Of the highland simulants, 08-1 has an integrated modal composition closer than NU-LHT-1M to that of the 64001/2 samples, However, this and other studies show that NU-LHT-1M and -2M have minor and trace mineral (e.g., Fe-Ti oxides and phosphates) populations and mineral and glass chemistry closer to these lunar samples. The finest fractions (0-20 microns) in the sieved lunar samples are enriched in glass relative to the integrated compositions by approx.30% for 64002,262 and approx.15% for 64001,374. Plagioclase, pyroxene, and olivine are depleted in these finest fractions. This could be important to lunar dust mitigation efforts and astronaut health - none of the analyzed simulants show this trend. Contrary to previously reported modal analyses of monomineralic grains in lunar regolith, these area% modal analyses do not show a systematic increase in plagiociase/pyroxene as size fraction decreases.

  14. Experimental study on impact-induced seismic wave propagating through quartz sand simulating asteroid regolith

    NASA Astrophysics Data System (ADS)

    Matsue, Kazuma; Arakawa, Masahiko; Yasui, Minami; Matsumoto, Rie; Tsujido, Sayaka; Takano, Shota; Hasegawa, Sunao

    2015-08-01

    Introduction: Recent spacecraft surveys clarified that asteroid surfaces were covered with regolith made of boulders and pebbles such as that found on the asteroid Itokawa. It was also found that surface morphologies of asteroids formed on the regolith layer were modified. For example, the high-resolution images of the asteroid Eros revealed the evidence of the downslope movement of the regolith layer, then it could cause the degradation and the erasure of small impact crater. One possible process to explain these observations is the regolith layer collapse caused by seismic vibration after projectile impacts. The impact-induced seismic wave might be an important physical process affecting the morphology change of regolith layer on asteroid surfaces. Therefore, it is significant for us to know the relationship between the impact energy and the impact-induced seismic wave. So in this study, we carried out impact cratering experiments in order to observe the seismic wave propagating through the target far from the impact crater.Experimental method: Impact cratering experiments were conducted by using a single stage vertical gas gun set at Kobe Univ and a two-stage vertical gas gun set at ISAS. We used quartz sands with the particle diameter of 500μm, and the bulk density of 1.48g/cm3. The projectile was a ball made of polycarbonate with the diameter of 4.75mm and aluminum, titan, zirconia, stainless steel, cupper, tungsten carbide projectile with the diameter of 2mm. These projectiles were launched at the impact velocity from 0.2 to 7km/s. The target was set in a vacuum chamber evacuated below 10 Pa. We measured the seismic wave by using a piezoelectric uniaxial accelerometer.Result: The impact-induced seismic wave was measured to show a large single peak and found to attenuate with the propagation distance. The maximum acceleration of the seismic wave was recognized to have a good relationship with the normalized distance x/R, where x is the propagation distance and R is the crater radius, irrespective of the impact velocities: gmax = 160(x/R)-2.98.

  15. Development of Standardized Lunar Regolith Simulant Materials

    NASA Technical Reports Server (NTRS)

    Carpenter, P.; Sibille, L.; Meeker, G.; Wilson, S.

    2006-01-01

    Lunar exploration requires scientific and engineering studies using standardized testing procedures that ultimately support flight certification of technologies and hardware. It is necessary to anticipate the range of source materials and environmental constraints that are expected on the Moon and Mars, and to evaluate in-situ resource utilization (ISRU) coupled with testing and development. We describe here the development of standardized lunar regolith simulant (SLRS) materials that are traceable inter-laboratory standards for testing and technology development. These SLRS materials must simulate the lunar regolith in terms of physical, chemical, and mineralogical properties. A summary of these issues is contained in the 2005 Workshop on Lunar Regolith Simulant Materials [l]. Lunar mare basalt simulants MLS-1 and JSC-1 were developed in the late 1980s. MLS-1 approximates an Apollo 11 high-Ti basalt, and was produced by milling of a holocrystalline, coarse-grained intrusive gabbro (Fig. 1). JSC-1 approximates an Apollo 14 basalt with a relatively low-Ti content, and was obtained from a glassy volcanic ash (Fig. 2). Supplies of MLS-1 and JSC-1 have been exhausted and these materials are no longer available. No highland anorthosite simulant was previously developed. Upcoming lunar polar missions thus require the identification, assessment, and development of both mare and highland simulants. A lunar regolith simulant is manufactured from terrestrial components for the purpose of simulating the physical and chemical properties of the lunar regolith. Significant challenges exist in the identification of appropriate terrestrial source materials. Lunar materials formed under comparatively reducing conditions in the absence of water, and were modified by meteorite impact events. Terrestrial materials formed under more oxidizing conditions with significantly greater access to water, and were modified by a wide range of weathering processes. The composition space of lunar materials can be modeled by mixing programs utilizing a low-Ti basalt, ilmenite, KREEP component, high-Ca anorthosite, and meteoritic components. This approach has been used for genetic studies of lunar samples via chemical and modal analysis. A reduced composition space may be appropriate for simulant development, but it is necessary to determine the controlling properties that affect the physical, chemical and mineralogical components of the simulant.

  16. Moonshine: Diurnally varying hydration through natural distillation on the Moon, detected by the Lunar Exploration Neutron Detector (LEND)

    NASA Astrophysics Data System (ADS)

    Livengood, T. A.; Chin, G.; Sagdeev, R. Z.; Mitrofanov, I. G.; Boynton, W. V.; Evans, L. G.; Litvak, M. L.; McClanahan, T. P.; Sanin, A. B.; Starr, R. D.; Su, J. J.

    2015-07-01

    The Lunar Exploration Neutron Detector (LEND), on the polar-orbiting Lunar Reconnaissance Orbiter (LRO) spacecraft, has detected suppression in the Moon's naturally-occurring epithermal neutron leakage flux that is consistent with the presence of diurnally varying quantities of hydrogen in the regolith near the equator. Peak hydrogen concentration (neutron flux suppression) is on the dayside of the dawn terminator and diminishes through the dawn-to-noon sector. The minimum concentration of hydrogen is in the late afternoon and dusk sector. The chemical form of hydrogen is not determinable from these measurements, but other remote sensing methods and anticipated elemental availability suggest water molecules or hydroxyl ions. Signal-to-noise ratio at maximum contrast is 5.6σ in each of two detector systems. Volatiles are deduced to collect in or on the cold nightside surface and distill out of the regolith after dawn as rotation exposes the surface to sunlight. Liberated volatiles migrate away from the warm subsolar region toward the nearby cold nightside surface beyond the terminator, resulting in maximum concentration at the dawn terminator. The peak concentration within the upper ∼1 m of regolith is estimated to be 0.0125 ± 0.0022 weight-percent water-equivalent hydrogen (wt% WEH) at dawn, yielding an accumulation of 190 ± 30 ml recoverable water per square meter of regolith at each dawn. Volatile transport over the lunar surface in opposition to the Moon's rotation exposes molecules to solar ultraviolet radiation. The short lifetime against photolysis and permanent loss of hydrogen from the Moon requires a resupply rate that greatly exceeds anticipated delivery of hydrogen by solar wind implantation or by meteoroid impacts, suggesting that the surface inventory must be continually resupplied by release from a deep volatile inventory in the Moon. The natural distillation of water from the regolith by sunlight and its capture on the cold night surface may provide energy-efficient access to volatiles for in situ resource utilization (ISRU) by direct capture before volatiles can enter the surface, eliminating the need to actively mine regolith for volatile resource recovery.

  17. Corrosion-Resistant Container for Molten-Material Processing

    NASA Technical Reports Server (NTRS)

    Stern, Theodore G.; McNaul, Eric

    2010-01-01

    In a carbothermal process, gaseous methane is passed over molten regolith, which is heated past its melting point to a temperature in excess of 1,625 C. At this temperature, materials in contact with the molten regolith (or regolith simulant) corrode and lose their structural properties. As a result, fabricating a crucible to hold the molten material and providing a method of contact heating have been problematic. Alternative containment approaches use a large crucible and limit the heat zone of the material being processed, which is inefficient because of volume and mass constraints. Alternative heating approaches use non-contact heating, such as by laser or concentrated solar energy, which can be inefficient in transferring heat and thus require higher power heat sources to accomplish processing. The innovation is a combination of materials, with a substrate material having high structural strength and stiffness and high-temperature capability, and a coating material with a high corrosion resistance and high-temperature capability. The material developed is a molybdenum substrate with an iridium coating. Creating the containment crucible or heater jacket using this material combination requires only that the molybdenum, which is easily processed by conventional methods such as milling, electric discharge machining, or forming and brazing, be fabricated into an appropriate shape, and that the iridium coating be applied to any surfaces that may come in contact with the corrosive molten material. In one engineering application, the molybdenum was fashioned into a container for a heat pipe. Since only the end of the heat pipe is used to heat the regolith, the container has a narrowing end with a nipple in which the heat pipe is snugly fit, and the external area of this nipple, which contacts the regolith to transfer heat into it, is coated with iridium. At the time of this reporting, no single material has been found that can perform the functions of this combination of materials, and other combinations of materials have not proven to be survivable to the corrosiveness of this environment. High-temperature processing of materials with similar constituencies as lunar regolith is fairly common. The carbo-thermal process is commonly used to make metallurgical-grade silicon for the semiconductor and solar-cell industries.

  18. Moonshine: Diurnally varying hydration through natural distillation on the Moon, detected by the Lunar Exploration Neutron Detector (LEND)

    PubMed Central

    Livengood, T.A.; Chin, G.; Sagdeev, R.Z.; Mitrofanov, I.G.; Boynton, W.V.; Evans, L.G.; Litvak, M.L.; McClanahan, T.P.; Sanin, A.B.; Starr, R.D.; Su, J.J.

    2016-01-01

    The Lunar Exploration Neutron Detector (LEND), on the polar-orbiting Lunar Reconnaissance Orbiter (LRO) spacecraft, has detected suppression in the Moon’s naturally-occurring epithermal neutron leakage flux that is consistent with the presence of diurnally varying quantities of hydrogen in the regolith near the equator. Peak hydrogen concentration (neutron flux suppression) is on the dayside of the dawn terminator and diminishes through the dawn-to-noon sector. The minimum concentration of hydrogen is in the late afternoon and dusk sector. The chemical form of hydrogen is not determinable from these measurements, but other remote sensing methods and anticipated elemental availability suggest water molecules or hydroxyl ions. Signal-to-noise ratio at maximum contrast is 5.6σ in each of two detector systems. Volatiles are deduced to collect in or on the cold nightside surface and distill out of the regolith after dawn as rotation exposes the surface to sunlight. Liberated volatiles migrate away from the warm subsolar region toward the nearby cold nightside surface beyond the terminator, resulting in maximum concentration at the dawn terminator. The peak concentration within the upper ~1 m of regolith is estimated to be 0.0125 ± 0.0022 weight-percent water-equivalent hydrogen (wt% WEH) at dawn, yielding an accumulation of 190 ± 30 ml recoverable water per square meter of regolith at each dawn. Volatile transport over the lunar surface in opposition to the Moon’s rotation exposes molecules to solar ultraviolet radiation. The short lifetime against photolysis and permanent loss of hydrogen from the Moon requires a resupply rate that greatly exceeds anticipated delivery of hydrogen by solar wind implantation or by meteoroid impacts, suggesting that the surface inventory must be continually resupplied by release from a deep volatile inventory in the Moon. The natural distillation of water from the regolith by sunlight and its capture on the cold night surface may provide energy-efficient access to volatiles for in situ resource utilization (ISRU) by direct capture before volatiles can enter the surface, eliminating the need to actively mine regolith for volatile resource recovery. PMID:28798496

  19. From minerals to hillslopes: Towards an integrated framework for interpreting chemical and physical erosion

    NASA Astrophysics Data System (ADS)

    Hahm, W.; Riebe, C. S.; Ferrier, K.; Kirchner, J. W.

    2011-12-01

    Traditional frameworks for conceptualizing hillslope denudation distinguish between the movement of mass in solution (chemical erosion) and mass moved via mechanical processes (physical erosion). At the hillslope scale, physical and chemical erosion rates can be quantified by combining measurements of regolith chemistry with cosmogenic nuclide concentrations in bedrock and sediment, while basin-scale rates are often inferred from riverine solute and sediment loads. These techniques integrate the effects of numerous weathering and erosion mechanisms and do not provide prima facie information about the precise nature and scale of those mechanisms. For insight into erosional process, physical erosion has been considered in terms of two limiting regimes. When physical erosion outpaces weathering front advance, regolith is mobilized downslope as soon as it is sufficiently loosened by weathering, and physical erosion rates are limited by rates of mobile regolith production. This is commonly termed weathering-limited erosion. Conversely, when weathering front advance outpaces erosion, the mobile regolith layer grows thicker over time, and physical erosion rates are limited by the efficiency of downslope transport processes. This is termed transport-limited erosion. This terminology brings the description of hillslope evolution closer to the realm of essential realism, to the extent that measurable quantities from the field can be cast in a process-based framework. An analogous process-limitation framework describes chemical erosion. In supply-limited chemical erosion, chemical weathering depletes regolith of its reactive phases during residence on a hillslope, and chemical erosion rates are limited by the supply of fresh minerals to the weathering zone. Alternatively, hillslopes may exhibit kinetic-limited chemical erosion, where physical erosion transports regolith downslope before weatherable phases are completely removed by chemical erosion. We show how supply- and kinetic-limited chemical erosion can be distinguished from one another using data from a global compilation of physical and chemical erosion rates. As a step towards understanding these rates at the level of essential realism, we explore how the hillslope-scale regimes of supply- and kinetic-limited chemical erosion relate to existing conceptual frameworks that interpret weathering rates in terms of transport- and kinetic-limitation at the mineral scale.

  20. A Miniature Mineralogical Instrument for In-Situ Characterization of Ices and Hydrous Minerals at the Lunar Poles

    NASA Technical Reports Server (NTRS)

    Sarrazin, P.; Blake, D.; Vaniman, D.; Bish, D.; Chipera, S.; Collins, S. A.

    2002-01-01

    Lunar missions over the past few years have provided new evidence that water may be present at the lunar poles in the form of cold-trapped ice deposits, thereby rekindling interest in sampling the polar regions. Robotic landers fitted with mineralogical instrumentation for in-situ analyses could provide unequivocal answers on the presence of crystalline water ice and/or hydrous minerals at the lunar poles. Data from Lunar Prospector suggest that any surface exploration of the lunar poles should include the capability to drill to depths of more than 40 cm. Limited data on the lunar geotherm indicate temperatures of approximately 245-255 K at regolith depths of 40 cm, within a range where water may exist in the liquid state as brine. A relevant terrestrial analog occurs in Antarctica, where the zeolite mineral chabazite has been found at the boundary between ice-free and ice-cemented regolith horizons, and precipitation from a regolith brine is indicated. Soluble halogens and sulfur in the lunar regolith could provide comparable brine chemistry in an analogous setting. Regolith samples collected by a drilling device could be readily analyzed by CheMin, a mineralogical instrument that combines X-ray diffraction (XRD) and X-ray fluorescence (XRF) techniques to simultaneously characterize the chemical and mineralogical compositions of granular or powdered samples. CheMin can unambiguously determine not only the presence of hydrous alteration phases such as clays or zeolites, but it can also identify the structural variants or types of clay or zeolite present (e.g., well-ordered versus poorly ordered smectite; chabazite versus phillipsite). In addition, CheMin can readily measure the abundances of key elements that may occur in lunar minerals (Na, Mg, Al, Si, K, Ca, Fe) as well as the likely constituents of lunar brines (F, Cl, S). Finally, if coring and analysis are done during the lunar night or in permanent shadow, CheMin can provide information on the chemistry and structure of any crystalline ices that might occur in the regolith samples.

  1. Near surface bulk density estimates of NEAs from radar observations and permittivity measurements of powdered geologic material

    NASA Astrophysics Data System (ADS)

    Hickson, Dylan; Boivin, Alexandre; Daly, Michael G.; Ghent, Rebecca; Nolan, Michael C.; Tait, Kimberly; Cunje, Alister; Tsai, Chun An

    2018-05-01

    The variations in near-surface properties and regolith structure of asteroids are currently not well constrained by remote sensing techniques. Radar is a useful tool for such determinations of Near-Earth Asteroids (NEAs) as the power of the reflected signal from the surface is dependent on the bulk density, ρbd, and dielectric permittivity. In this study, high precision complex permittivity measurements of powdered aluminum oxide and dunite samples are used to characterize the change in the real part of the permittivity with the bulk density of the sample. In this work, we use silica aerogel for the first time to increase the void space in the samples (and decrease the bulk density) without significantly altering the electrical properties. We fit various mixing equations to the experimental results. The Looyenga-Landau-Lifshitz mixing formula has the best fit and the Lichtenecker mixing formula, which is typically used to approximate planetary regolith, does not model the results well. We find that the Looyenga-Landau-Lifshitz formula adequately matches Lunar regolith permittivity measurements, and we incorporate it into an existing model for obtaining asteroid regolith bulk density from radar returns which is then used to estimate the bulk density in the near surface of NEA's (101955) Bennu and (25143) Itokawa. Constraints on the material properties appropriate for either asteroid give average estimates of ρbd = 1.27 ± 0.33g/cm3 for Bennu and ρbd = 1.68 ± 0.53g/cm3 for Itokawa. We conclude that our data suggest that the Looyenga-Landau-Lifshitz mixing model, in tandem with an appropriate radar scattering model, is the best method for estimating bulk densities of regoliths from radar observations of airless bodies.

  2. Some Expected Characteristics of Lunar Dust: A Geological View Applied to Engineering

    NASA Technical Reports Server (NTRS)

    Street, Kenneth W.; Schrader, Christian M.; Rickman, Doug

    2008-01-01

    Compared to the Earth the geologic nature of the lunar regolith is quite distinct. Even though similar minerals exist on the Earth and Moon, they may have very different properties due to the absence of chemical modification in the lunar environment. The engineering properties of the lunar regolith reflect aspects of the parent rock and the consequences of hypervelocity meteor bombardment. On scales relevant to machinery and chemical processing for In-Situ Resource Utilization, ISRU (such as water production), the lunar regolith compositional range is much more restricted than terrestrial material. This fact impacts predictions of properties required by design engineers for constructing equipment for lunar use. In this paper two examples will be covered. 1) Abrasion is related to hardness and hardness is a commonly measured property for both minerals and engineering materials. Although different hardness scales are routinely employed for minerals and engineering materials, a significant amount of literature is available relating the two. As one example, we will discuss how to relate hardness to abrasion for the design of lunar equipment. We also indicate how abundant the various mineral phases are and typical size distributions for lunar regolith which will impact abrasive nature. 2) Mineral characteristics that may seem trivial to the non-geologist or material scientist may have significant bearing on ISRU processing technologies. As a second example we discuss the impact of traces of F-, Cl-, and OH-, H2O, CO2, and sulfur species which can radically alter melting points and the corrosive nature of reaction products thereby significantly changing bulk chemistry and associated processing technologies. For many engineering uses, a simulant s fidelity to bulk lunar regolith chemistry may be insufficient. Therefore, simulant users need to engage in continuing dialogue with simulant developers and geoscientists.

  3. Some Expected Characteristics of Lunar Dust: A Geological View Applied to Engineering

    NASA Technical Reports Server (NTRS)

    Street, Kenneth W.; Schrader, Christian M.; Rickman, Doug

    2008-01-01

    Compared to the Earth the geologic nature of the lunar regolith is quite distinct. Even though similar minerals exist on the Earth and Moon, they may have very different properties due to the absence of chemical modification in the lunar environment. The engineering properties of the lunar regolith reflect aspects of the parent rock and the consequences of hypervelocity meteor bombardment. On scales relevant to machinery and chemical processing for In-Situ Resource Utilization, ISRU (such as water production), the lunar regolith compositional range is much more restricted than terrestrial material. This fact impacts predictions of properties required by design engineers for constructing equipment for lunar use. In this paper two examples will be covered. 1) Abrasion is related to hardness and hardness is a commonly measured property for both minerals and engineering materials. Although different hardness scales are routinely employed for minerals and engineering materials, a significant amount of literature is available relating the two. As one example, we will discuss how to relate hardness to abrasion for the design of lunar equipment. We also indicate how abundant the various mineral phases are and typical size distributions for lunar regolith which will impact abrasive nature. 2) Mineral characteristics that may seem trivial to the non-geologist or material scientist may have significant bearing on ISRU processing technologies. As a second example we discuss the impact of traces of fluoride, chloride, and hydroxide, water, carbon dioxide, and sulfur species which can radically alter melting points and the corrosive nature of reaction products thereby significantly changing bulk chemistry and associated processing technologies. For many engineering uses, a simulant's fidelity to bulk lunar regolith chemistry may be insufficient. Therefore, simulant users need to engage in continuing dialogue with simulant developers and geoscientists.

  4. A Functional Comparison of Lunar Regoliths and Their Simulants

    NASA Technical Reports Server (NTRS)

    Rickman, D.; Edmunson, J.; McLemore, C.

    2012-01-01

    Lunar regolith simulants are essential to the development of technology for human exploration of the Moon. Any equipment that will interact with the surface environment must be tested with simulant to mitigate risk. To reduce the greatest amount of risk, the simulant must replicate the lunar surface as well as possible. To quantify the similarities and differences between simulants, the Figures of Merit were developed. The Figures of Merit software compares the simulants and regolith by particle size, particle shape, density, and bulk chemistry and mineralogy; these four properties dictate the majority of the remaining characteristics of a geologic material. There are limitations to both the current Figures of Merit approach and simulants in general. The effect of particle textures is lacking in the Figures of Merit software, and research into this topic has only recently begun with applications to simulants. In addition, not all of the properties for lunar regolith are defined sufficiently for simulant reproduction or comparison; for example, the size distribution of particles greater than 1 centimeter and the makeup of particles less than 10 micrometers is not well known. For simulants, contamination by terrestrial weathering products or undesired trace phases in feedstock material is a major issue. Vapor deposited rims have not yet been created for simulants. Fortunately, previous limitations such as the lack of agglutinates in simulants have been addressed and commercial companies are now making agglutinate material for simulants. Despite some limitations, the Figures of Merit sufficiently quantify the comparison between simulants and regolith for useful application in lunar surface technology. Over time, the compilation and analysis of simulant user data will add an advantageous predictive capability to the Figures of Merit, accurately relating Figures of Merit characteristics to simulant user parameters.

  5. Boulder Distributions at Legacy Landing Sites: Assessing Regolith Production Rates and Landing Site Hazards

    NASA Technical Reports Server (NTRS)

    Watkins, R. N.; Jolliff, B. L.; Lawrence, S. J.; Hayne, P. O.; Ghent, R. R.

    2017-01-01

    Understanding how the distribution of boulders on the lunar surface changes over time is key to understanding small-scale erosion processes and the rate at which rocks become regolith. Boulders degrade over time, primarily as a result of micrometeorite bombardment so their residence time at the surface can inform the rate at which rocks become regolith or become buried within regolith. Because of the gradual degradation of exposed boulders, we expect that the boulder population around an impact crater will decrease as crater age increases. Boulder distributions around craters of varying ages are needed to understand regolith production rates, and Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) images provide one of the best tools for conducting these studies. Using NAC images to assess how the distribution of boulders varies as a function of crater age provides key constraints for boulder erosion processes. Boulders also represent a potential hazard that must be addressed in the planning of future lunar landings. A boulder under a landing leg can contribute to deck tilt, and boulders can damage spacecraft during landing. Using orbital data to characterize boulder populations at locations where landers have safely touched down (Apollo, Luna, Surveyor, Chang'e-3) provides validation for landed mission hazard avoidance planning. Additionally, counting boulders at legacy landing sites is useful because: 1) LROC has extensive coverage of these sites at high resolutions (approximately 0.5 meters per pixel). 2) Returned samples from craters at these sites have been radiometrically dated, allowing assessment of how boulder distributions vary as a function of crater age. 3) Surface photos at these sites can be used to correlate with remote sensing measurements.

  6. In situ measurement of soil moisture and pore-water pressures in an 'incipient' landslide: Lake Tutira, New Zealand.

    PubMed

    Hawke, Richard; McConchie, Jack

    2011-02-01

    The immediate cost of shallow regolith landslides in New Zealand has been estimated to exceed US$33M annually. Since the majority of these landslides occur during prolonged wet conditions, or intense rainstorms, moisture conditions are a critical control. The nature, dynamics, and character of soil moisture conditions, and the piezometric response to rainfall, have been recorded within an 'incipient' landslide for more than 5 years. The study site, on pastoral hill country within the Lake Tutira catchment in northern Hawkes Bay, is typical of large areas of New Zealand episodically affected by extensive landsliding. Detailed continuous measurements show that both the soil moisture and piezometric response within the regolith are highly storm- and site-specific. The development of positive pore pressures is infrequent; they form only during intense rainstorms, and persist for a short time. The hydraulic response of the soil is primarily a function of storm characteristics, but this response can be modified by antecedent moisture conditions, topographic position, and heterogeneity of soil properties. Stability analysis shows that most slopes in the study area are significantly steeper than can be explained by the frictional strength of the regolith. Measured hydraulic conditions also show that positive pore-water pressures alone do not trigger slope instability. A recent slope failure followed a period of extremely high antecedent moisture conditions, and occurred when maximum soil moisture conditions, though not pore-water pressures, were recorded. Increased moisture content of the regolith reduces matric tension, and therefore effective cohesion of the soil. This cohesion is critical to maintaining stability of the regolith on these slopes. Copyright © 2009 Elsevier Ltd. All rights reserved.

  7. Potential Use of In Situ Material Composites such as Regolith/Polyethylene for Shielding Space Radiation

    NASA Technical Reports Server (NTRS)

    Theriot, Corey A.; Gersey, Buddy; Bacon, Eugene; Johnson, Quincy; Zhang, Ye; Norman, Jullian; Foley, Ijette; Wilkins, Rick; Zhou, Jianren; Wu, Honglu

    2010-01-01

    NASA has an extensive program for studying materials and methods for the shielding of astronauts to reduce the effects of space radiation when on the surfaces of the Moon and Mars, especially in the use of in situ materials native to the destination reducing the expense of materials transport. The most studied material from the Moon is Lunar regolith and has been shown to be as efficient as aluminum for shielding purposes (1). The addition of hydrogenous materials such as polyethylene should increase shielding effectiveness and provide mechanical properties necessary of structural materials (2). The neutron radiation shielding effectiveness of polyethylene/regolith stimulant (JSC-1A) composites were studied using confluent human fibroblast cell cultures exposed to a beam of high-energy spallation neutrons at the 30deg-left beam line (ICE house) at the Los Alamos Neutron Science Center. At this angle, the radiation spectrum mimics the energy spectrum of secondary neutrons generated in the upper atmosphere and encountered when aboard spacecraft and high-altitude aircraft. Cell samples were exposed in series either directly to the neutron beam, within a habitat created using regolith composite blocks, or behind 25 g/sq cm of loose regolith bulk material. In another experiment, cells were also exposed in series directly to the neutron beam in T-25 flasks completely filled with either media or water up to a depth of 20 cm to test shielding effectiveness versus depth and investigate the possible influence of secondary particle generation. All samples were sent directly back to JSC for sub-culturing and micronucleus analysis. This presentation is of work performed in collaboration with the NASA sponsored Center for Radiation Engineering and Science for Space Exploration (CRESSE) at Prairie View A&M.

  8. Determining mineral weathering rates based on solid and solute weathering gradients and velocities: Application to biotite weathering in saprolites

    USGS Publications Warehouse

    White, A.F.

    2002-01-01

    Chemical weathering gradients are defined by the changes in the measured elemental concentrations in solids and pore waters with depth in soils and regoliths. An increase in the mineral weathering rate increases the change in these concentrations with depth while increases in the weathering velocity decrease the change. The solid-state weathering velocity is the rate at which the weathering front propagates through the regolith and the solute weathering velocity is equivalent to the rate of pore water infiltration. These relationships provide a unifying approach to calculating both solid and solute weathering rates from the respective ratios of the weathering velocities and gradients. Contemporary weathering rates based on solute residence times can be directly compared to long-term past weathering based on changes in regolith composition. Both rates incorporate identical parameters describing mineral abundance, stoichiometry, and surface area. Weathering gradients were used to calculate biotite weathering rates in saprolitic regoliths in the Piedmont of Northern Georgia, USA and in Luquillo Mountains of Puerto Rico. Solid-state weathering gradients for Mg and K at Panola produced reaction rates of 3 to 6 x 10-17 mol m-2 s-1 for biotite. Faster weathering rates of 1.8 to 3.6 ?? 10-16 mol m-2 s-1 are calculated based on Mg and K pore water gradients in the Rio Icacos regolith. The relative rates are in agreement with a warmer and wetter tropical climate in Puerto Rico. Both natural rates are three to six orders of magnitude slower than reported experimental rates of biotite weathering. ?? 2002 Elsevier Science B.V. All rights reserved.

  9. RESOLVE's Field Demonstration on Mauna Kea, Hawaii 2010

    NASA Technical Reports Server (NTRS)

    Captain, Janine; Quinn, Jacqueline; Moss, Thomas; Weis, Kyle

    2010-01-01

    In cooperation with the Canadian Space Agency, and the Northern Centre for Advanced Technology, Inc., NASA has undertaken the In-Situ Resource Utilization (ISRU) project called RESOLVE (Regolith and Environment Science & Oxygen and Lunar Volatile Extraction). This project is an Earth-based lunar precursor demonstration of a system that could be sent to explore permanently shadowed polar lunar craters, where it would drill into regolith, quantify the volatiles that are present, and extract oxygen by hydrogen reduction of iron oxides. The resulting water could be electrolyzed into oxygen to support exploration and hydrogen, which would be recycled through the process. The RESOLVE chemical processing system was mounted on a Canadian Space Agency mobility chasis and successfully demonstrated on Hawaii's Mauna Kea volcano in February 2010. The RESOLVE unit is the initial prototype of a robotic prospecting mission to the Moon. RESOLVE is designed to go to the poles of the Moon to "ground truth" the form and concentration of the hydrogen/water/hydroxyl that has been seen from orbit (M3, Lunar Prospector and LRO) and to test technologies to extract oxygen from the lunar regolith. RESOLVE has the ability to capture a one-meter core sample of lunar regolith and heat it to determine the volatiles that may be released and then demonstrate the production of oxygen from minerals found in the regolith. The RESOLVE project, which is led by KSC, is a multi-center and multi-organizational effort that includes representatives from KSC, JSC, GRC, the Canadian Space Agency, and the Northern Center for Advanced Technology (NORCAT). This paper details the results obtained from four days of lunar analog testing that included gas chromatograph analysis for volatile components, remote control of chemistry and drilling operations via satalite communications, and real-time water quantification using a novel capacitance measurement technique.

  10. Nanoscale Mineralogy and Composition of Experimental Regolith Agglutinates Produced under Asteroidal Impact Conditions

    NASA Technical Reports Server (NTRS)

    Christoffersen, Roy; Cintala, M. J.; Keller, L. P.; See, T. H.; Horz, F.

    2013-01-01

    On the Moon, the energetics of smaller impactors and the physical/chemical characteristics of the granular regolith target combine to form a key product of lunar space weathering: chemically reduced shock melts containing optically-active nanophase Fe metal grains (npFe0) [1]. In addition to forming the optically dark glassy matrix phase in lunar agglutinitic soil particles [1], these shock melts are becoming increasingly recognized for their contribution to optically active patina coatings on a wide range of exposed rock and grain surfaces in the lunar regolith [2]. In applying the lessons of lunar space weathering to asteroids, the potential similarities and differences in regolith-hosted shock melts on the Moon compared to those on asteroids has become a topic of increasing interest [3,4]. In a series of impact experiments performed at velocities applicable to the asteroid belt [5], Horz et al. [6] and See and Horz [7] have previously shown that repeated impacts into a gabbroic regolith analog target can produce melt-welded grain aggregates morphologically very similar to lunar agglutinates [6,7]. Although these agglutinate-like particles were extensively analyzed by electron microprobe and scanning electron microscopy (SEM) as part of the original study [7], a microstructural and compositional comparison of these aggregates to lunar soil agglutinates at sub-micron scales has yet to be made. To close this gap, we characterized a representative set of these aggregates using a JEOL 7600 field-emission scanning electron microscope (FE-SEM), and JEOL 2500SE field-emission scanning transmission electron microscope (FE-STEM) both optimized for energy dispersive X-ray spectroscopy (EDX) compositional spectrum imaging at respective analytical spatial resolutions of 0.5 to 1 micron, and 2 to 4 nm.

  11. Conceptual design of a fleet of autonomous regolith throwing devices for radiation shielding of lunar habitats

    NASA Technical Reports Server (NTRS)

    Armstrong, Karem; Mcadams, Daniel A.; Norrell, Jeffery L.

    1992-01-01

    The National Aeronautics and Space Administration (NASA) in conjunction with Universities Space Research Association (USRA) has requested that the feasibility of a fleet of regolith tossing devices designed to cover a lunar habitat for radiation protection be demonstrated. The regolith, or lunar soil, protects the lunar habitat and its inhabitants from radiation. Ideally, the device will operate autonomously in the lunar environment. To prove the feasibility of throwing regolith on the Moon, throwing solutions were compared to traditional, Earth-based methods for moving soil. Various throwing configurations were investigated. A linear throwing motion combined with a spring and motor energizing system proved a superior solution. Three different overall configurations for the lunar device are presented. A single configuration is chosen and critical parameters such as operating procedure, system volume, mass, and power are developed. The report is divided into seven main sections. First, the Introduction section gives background information, defines the project requirements and the design criteria, and presents the methodology used for the completion of this design. Next, the Preliminary Analysis section presents background information on characteristics of lunar habitats and the lunar environment. Then, the Alternate Designs section presents alternate solutions to each of the critical functions of the device. Fourth, a detailed analysis of throwing the regolith is done to demonstrate its feasibility. Then, the three overall design configurations are presented. Next, a configuration is selected and the conceptual design is expanded to include system performance characteristics, size, and mass. Finally, the Conclusions and Recommendations for Future Work section evaluates the design, outlines the next step to be taken in the design process, and suggests possible goals for future design work.

  12. Simultaneous laboratory measurements of CO2 and H2O adsorption on palagonite: Implications for the Martian climate and volatile reservoir

    NASA Technical Reports Server (NTRS)

    Zent, A. P.; Quinn, R.

    1993-01-01

    We are measuring the simultaneous adsorption of H2O and CO2 on palagonite materials in order to improve the formulation of climate models for Mars. We report on the initial co-adsorption data. Models of the Martian climate and volatile inventory indicate that the regolith serves as one of the primary reservoirs of outgassed volatiles and that it exchanges H2O and CO2 with the atmosphere in response to changes in insolation associated with astronomical cycles. Physical adsorbate must exist on the surfaces of the cold particulates that constitute the regolith, and the size of that reservoir can be assessed through laboratory measurements of adsorption on terrestrial analogs. Many studies of the independent adsorption of H2O and CO2 on Mars analog were made and appear in the literature. Empirical expressions that relate the adsorptive coverage of each gas to the temperature of the soil and partial pressure have been derived based on the laboratory data. Numerical models incorporate these adsorption isotherms into climatic models, which predict how the adsorptive coverage of the regolith and hence, the pressure of each gas in the atmosphere will vary as the planet moves through its orbit. These models suggest that the regolith holds several tens to hundreds of millibars of CO2 and that during periods of high obliquity warming of the high-latitude regolith will result in desorption of the CO2, and a consequent increase in atmospheric pressure. At lower obliquities, the caps cool and the equator warms forcing the desorption of several tens of millibars of CO2, which is trapped into quasipermanent CO2 caps.

  13. Modelling chemical depletion profiles in regolith

    USGS Publications Warehouse

    Brantley, S.L.; Bandstra, J.; Moore, J.; White, A.F.

    2008-01-01

    Chemical or mineralogical profiles in regolith display reaction fronts that document depletion of leachable elements or minerals. A generalized equation employing lumped parameters was derived to model such ubiquitously observed patterns:C = frac(C0, frac(C0 - Cx = 0, Cx = 0) exp (??ini ?? over(k, ??) ?? x) + 1)Here C, Cx = 0, and Co are the concentrations of an element at a given depth x, at the top of the reaction front, or in parent respectively. ??ini is the roughness of the dissolving mineral in the parent and k???? is a lumped kinetic parameter. This kinetic parameter is an inverse function of the porefluid advective velocity and a direct function of the dissolution rate constant times mineral surface area per unit volume regolith. This model equation fits profiles of concentration versus depth for albite in seven weathering systems and is consistent with the interpretation that the surface area (m2 mineral m- 3 bulk regolith) varies linearly with the concentration of the dissolving mineral across the front. Dissolution rate constants can be calculated from the lumped fit parameters for these profiles using observed values of weathering advance rate, the proton driving force, the geometric surface area per unit volume regolith and parent concentration of albite. These calculated values of the dissolution rate constant compare favorably to literature values. The model equation, useful for reaction fronts in both steady-state erosional and quasi-stationary non-erosional systems, incorporates the variation of reaction affinity using pH as a master variable. Use of this model equation to fit depletion fronts for soils highlights the importance of buffering of pH in the soil system. Furthermore, the equation should allow better understanding of the effects of important environmental variables on weathering rates. ?? 2008.

  14. Strong climate and tectonic control on plagioclase weathering in granitic terrain

    USGS Publications Warehouse

    Rasmussen, C.; Brantley, S.; Richter, D.D.B.; Blum, A.; Dixon, J.; White, A.F.

    2011-01-01

    Investigations to understand linkages among climate, erosion and weathering are central to quantifying landscape evolution. We approach these linkages through synthesis of regolith data for granitic terrain compiled with respect to climate, geochemistry, and denudation rates for low sloping upland profiles. Focusing on Na as a proxy for plagioclase weathering, we quantified regolith Na depletion, Na mass loss, and the relative partitioning of denudation to physical and chemical contributions. The depth and magnitude of regolith Na depletion increased continuously with increasing water availability, except for locations with mean annual temperature <5??C that exhibited little Na depletion, and locations with physical erosion rates <20gm-2yr-1 that exhibited deep and complete regolith Na depletion. Surface Na depletion also tended to decrease with increasing physical erosion. Depth-integrated Na mass loss and regolith depth were both three orders of magnitude greater in the fully depleted, low erosion rate sites relative to other locations. These locations exhibited strong erosion-limitation of Na chemical weathering rates based on correlation of Na chemical weathering rate to total Na denudation. Sodium weathering rates in cool locations with positive annual water balance were strongly correlated to total Na denudation and precipitation, and exhibited an average apparent activation energy (Ea) of 69kJmol-1 Na. The remaining water-limited locations exhibited kinetic limitation of Na weathering rates with an Ea of 136kJmol-1 Na, roughly equivalent to the sum of laboratory measures of Ea and dissolution reaction enthalpy for albite. Water availability is suggested as the dominant factor limiting rate kinetics in the water-limited systems. Together, these data demonstrate marked transitions and nonlinearity in how climate and tectonics correlate to plagioclase chemical weathering and Na mass loss. ?? 2010 Elsevier B.V.

  15. Space Plasma Ion Processing of Ilmenite in the Lunar Soil: Insights from In-Situ TEM Ion Irradiation Experiments

    NASA Technical Reports Server (NTRS)

    Christoffersen, R.; Keller, L. P.

    2007-01-01

    Space weathering on the moon and asteroids results largely from the alteration of the outer surfaces of regolith grains by the combined effects of solar ion irradiation and other processes that include deposition of impact or sputter-derived vapors. Although no longer considered the sole driver of space weathering, solar ion irradiation remains a key part of the space weathering puzzle, and quantitative data on its effects on regolith minerals are still in short supply. For the lunar regolith, previous transmission electron microscope (TEM) studies performed by ourselves and others have uncovered altered rims on ilmenite (FeTiO3) grains that point to this phase as a unique "witness plate" for unraveling nanoscale space weathering processes. Most notably, the radiation processed portions of these ilmenite rims consistently have a crystalline structure, in contrast to radiation damaged rims on regolith silicates that are characteristically amorphous. While this has tended to support informal designation of ilmenite as a "radiation resistant" regolith mineral, there are to date no experimental data that directly and quantitatively compare ilmenite s response to ion radiation relative to lunar silicates. Such data are needed because the radiation processed rims on ilmenite grains, although crystalline, are microstructurally and chemically complex, and exhibit changes linked to the formation of nanophase Fe metal, a key space weathering process. We report here the first ion radiation processing study of ilmenite performed by in-situ means using the Intermediate Voltage Electron Microscope- Tandem Irradiation facility (IVEM-Tandem) at Argonne National Laboratory. The capability of this facility for performing real time TEM observations of samples concurrent with ion irradiation makes it uniquely suited for studying the dose-dependence of amorphization and other changes in irradiated samples.

  16. Production of lunar fragmental material by meteoroid impact.

    NASA Technical Reports Server (NTRS)

    Marcus, A. H.

    1973-01-01

    The rate of production of new fragmental lunar surface material is derived theoretically on the hypothesis that such material is excavated from a bedrock layer by meteoroid impacts. An overlaying regolith effectively shields the bedrock layer from small impacts, reducing the production rate of centimeter-sized and smaller blocks by a large factor. Logarithmic production rate curves for centimeter to motor-sized blocks are nonlinear for any regolith from centimeters to tens of meters in thickness, with small blocks relatively much less frequent for thicker (older) regoliths, suggesting the possibility of a statistical reverse bedding. Modest variations in the exponents of scaling laws for crater depth-diameter ratio and maximum block-diameter to crater diameter ratio are shown to have significant effects on the production rates. The production rate increases slowly with increasing size of the largest crater affecting the region.

  17. Sulfate Deposition in Regolith Exposed in Trenches on the Plains Between the Spirit Landing Site and Columbia Hills in Gusev Crater, Mars

    NASA Technical Reports Server (NTRS)

    Wang, Alian; Haskin, L. A.; Squyres, S. W.; Arvidson, R.; Crumpler, L.; Gellert, R.; Hurowitz, J.; Schroeder, C.; Tosca, N.; Herkenhoff, K.

    2005-01-01

    During its exploration within Gusev crater between sol 01 and sol 158, the Spirit rover dug three trenches (Fig. 1) to expose the subsurface regolith [1, 2, 9]. Laguna trench (approx. 6 cm deep, approx.203 m from the rim of Bonneville crater) was dug in Laguna Hollow at the boundary of the impact ejecta from Bonneville crater and the surrounding plains. The Big Hole trench (approx. 6-7 cm deep) and The Boroughs trench (approx. 11 cm deep) were dug in the plains between the Bonneville crater and the Columbia Hills (approx.556 m and approx.1698 m from the rim of Bonneville crater respectively). The top, wall and floor regolith of the three trenches were investigated using the entire set of Athena scientific instruments [10].

  18. Evidence for Impact Shock Melting in CM and CI Chondrite Regolith Samples

    NASA Technical Reports Server (NTRS)

    Zolensky, Michael; Mikouchi, Takashi; Hagiya, Kenji; Ohsumi, Kazumasa; Komatsu, Mutsumi; Le, Loan

    2014-01-01

    C class asteroids frequently exhibit reflectance spectra consistent with thermally metamorphosed carbonaceous chondrites, or a mixture of phyllosilicate-rich material along with regions where they are absent. One particularly important example appears to be near-Earth asteroid 1999 JU3, the target of the Hayabusa II sample return mission [1], although not all spectra indicate this. In fact most spectra of 1999 JU3 are featureless, suggesting a heterogeneous regolith. Here we explore an alternative cause of dehydration of regolith of C class asteroids - impact shock melting. Impact shock melting has been proposed to explain some mineralogical characteristics of CB chondrites, but has not been considered a major process for hydrous carbonaceous chondrites. What evidence is there for significant shock melting in the very abundant CMs, or less abundant but still important CI chondrites?

  19. PROGRA2 experiment: New results for dust clouds and regoliths analogs

    NASA Astrophysics Data System (ADS)

    Hadamcik, E.; Renard, J.-B.; Levasseur-Regourd, A. C.; Worms, J.-C.

    2006-01-01

    With the PROGRA2 experience, linear polarization of scattered light is measured on various types of dust clouds lifted by microgravity, or by an air-draught. The aim is to compare the phase curves for dust analogs with those obtained in the Solar System (cometary comae, and solid particles in planetary atmospheres) by remote-sensing and in situ techniques. Measurements are also performed on layers of particles (on the ground) and compared with remote measurements on asteroidal regoliths and planetary surfaces. New phase curves have been obtained, e.g., for quartz samples, crystals, fluffy mixtures of silica and carbon blacks and a high porosity regolith analog made of micron-sized silica spheres. This work will contribute to the choice of the samples to be studied with the ICAPS experiment onboard the ISS and on the precursor experiment.

  20. Advances in Molten Oxide Electrolysis for the Production of Oxygen and Metals from Lunar Regolith

    NASA Technical Reports Server (NTRS)

    Sadoway, Donald R.; Sirk, Aislinn; Sibille, Laurent; Melendez, Orlando; Lueck, Dale; Curreri, Peter; Dominquez, Jesus; Whitlow, Jonathan

    2008-01-01

    As part of an In-Situ Resource Utilization infrastructure to sustain long term-human presence on the lunar surface, the production of oxygen and metals by electrolysis of lunar regolith has been the subject of major scrutiny. There is a reasonably large body of literature characterizing the candidate solvent electrolytes, including ionic liquids, molten salts, fluxed oxides, and pure molten regolith itself. In the light of this information and in consideration of available electrolytic technologies, the authors have determined that direct molten oxide electrolysis at temperatures of approx 1600 C is the most promising avenue for further development. Results from ongoing studies as well as those of previous workers will be presented. Topics include materials selection and testing, electrode stability, gas capture and analysis, and cell operation during feeding and tapping.

  1. An Improved Instrument for Investigating Planetary Regolith Microstructure

    NASA Technical Reports Server (NTRS)

    Nelson, R. M.; Hapke, B. W.; Smythe, W. D.; Manatt, K. S.; Eddy, J.

    2005-01-01

    The Opposition Effect (OE) is the non-linear increase in the intensity of light scattered from a surface as phase angle approaches 0 deg. It is seen in laboratory experiments and in remote sensing observations of planetary surfaces. Understanding the OE is a requirement for fitting photometric models which produce meaningful results about regolith texture. Previously we have reported measurements from the JPL long arm goniometer and we have shown that this instrument enables us to distinguish between two distinct processes which create the opposition surges, Shadow Hiding (SHOE) and Coherent Backscattering (CBOE). SHOE arises because, as phase angle approaches zero, shadows cast by regolith grains on other grains become invisible to the observer. CBOE results from constructive interference between rays traveling the same path but in opposite directions. Additional information is included in the original extended abstract.

  2. Samples from Differentiated Asteroids; Regolithic Achondrites

    NASA Technical Reports Server (NTRS)

    Herrin J. S.; Ross, A. J.; Cartwright, J. A.; Ross, D. K.; Zolensky, Michael E.; Jenniskens, P.

    2011-01-01

    Differentiated and partially differentiated asteroids preserve a glimpse of planet formation frozen in time from the early solar system and thus are attractive targets for future exploration. Samples of such asteroids arrive to Earth in the form of achondrite meteorites. Many achondrites, particularly those thought to be most representative of asteroidal regolith, contain a diverse assortment of materials both indigenous and exogenous to the original igneous parent body intermixed at microscopic scales. Remote sensing spacecraft and landers would have difficulty deciphering individual components at these spatial scales, potentially leading to confusing results. Sample return would thus be much more informative than a robotic probe. In this and a companion abstract [1] we consider two regolithic achondrite types, howardites and (polymict) ureilites, in order to evaluate what materials might occur in samples returned from surfaces of differentiated asteroids and what sampling strategies might be prudent.

  3. Lunar surface vehicle model competition

    NASA Technical Reports Server (NTRS)

    1990-01-01

    During Fall and Winter quarters, Georgia Tech's School of Mechanical Engineering students designed machines and devices related to Lunar Base construction tasks. These include joint projects with Textile Engineering students. Topics studied included lunar environment simulator via drop tower technology, lunar rated fasteners, lunar habitat shelter, design of a lunar surface trenching machine, lunar support system, lunar worksite illumination (daytime), lunar regolith bagging system, sunlight diffusing tent for lunar worksite, service apparatus for lunar launch vehicles, lunar communication/power cables and teleoperated deployment machine, lunar regolith bag collection and emplacement device, soil stabilization mat for lunar launch/landing site, lunar rated fastening systems for robotic implementation, lunar surface cable/conduit and automated deployment system, lunar regolith bagging system, and lunar rated fasteners and fastening systems. A special topics team of five Spring quarter students designed and constructed a remotely controlled crane implement for the SKITTER model.

  4. Exploring Fingerprints of the Extreme Thermoacidophile Metallosphaera sedula Grown on Synthetic Martian Regolith Materials as the Sole Energy Sources.

    PubMed

    Kölbl, Denise; Pignitter, Marc; Somoza, Veronika; Schimak, Mario P; Strbak, Oliver; Blazevic, Amir; Milojevic, Tetyana

    2017-01-01

    The biology of metal transforming microorganisms is of a fundamental and applied importance for our understanding of past and present biogeochemical processes on Earth and in the Universe. The extreme thermoacidophile Metallosphaera sedula is a metal mobilizing archaeon, which thrives in hot acid environments (optimal growth at 74°C and pH 2.0) and utilizes energy from the oxidation of reduced metal inorganic sources. These characteristics of M. sedula make it an ideal organism to further our knowledge of the biogeochemical processes of possible life on extraterrestrial planetary bodies. Exploring the viability and metal extraction capacity of M. sedula living on and interacting with synthetic extraterrestrial minerals, we show that M. sedula utilizes metals trapped in the Martian regolith simulants (JSC Mars 1A; P-MRS; S-MRS; MRS07/52) as the sole energy sources. The obtained set of microbiological and mineralogical data suggests that M. sedula actively colonizes synthetic Martian regolith materials and releases free soluble metals. The surface of bioprocessed Martian regolith simulants is analyzed for specific mineralogical fingerprints left upon M. sedula growth. The obtained results provide insights of biomining of extraterrestrial material as well as of the detection of biosignatures implementing in life search missions.

  5. Are Planetary Regolith Particles Back Scattering? Response to a Paper by M. Mishchenko

    NASA Technical Reports Server (NTRS)

    Hapke, Bruce

    1996-01-01

    In a recent paper Mishchenko asserts that soil particles are strongly forward scattering, whereas particles on the surfaces of objects in the solar system have been inferred to be back scattering. Mishchenko suggests that this apparent discrepancy is an artifact caused by using an approximate light scattering model to analyse the data, and that planetary regolith particles are actually strong forward scatterers. The purpose of the present paper is to point out the errors in Mishchenko's paper and to show from both theoretical arguments and experimental data that inhomogencous composite particles which are large compared to the wavelength of visible light, such as rock fragments and agglutinates, can be strongly back scattering and are the fundamental scatterers in media composed of them. Such particles appear to be abundant in planetary regoliths and can account for the back scattering character of the surfaces of many bodies in the solar system. If the range of phase angles covered by a data set is insufficient, serious errors in retrieving the particle scattering properties can result whether an exact or approximate scattering model is used. However, if the data set includes both large and small phase angles, approximate regolith scattering models can correctly retrieve the sign of the particle scattering asymmetry.

  6. Prospects for Dating the South Pole-Aitken Basin through Impact-Melt Rock Samples

    NASA Technical Reports Server (NTRS)

    Cohen, B. A.; Coker, R. F.; Petro, N. E.

    2016-01-01

    Much of the present debate about the ages of the nearside basins arises because of the difficulty in understanding the relationship of recovered samples to their parent basin. The Apollo breccias are from basin ejecta formations, which are ballistically-emplaced distal deposits that have mixed provenances. The Nectaris, Imbrium, and Serenitatis basins all have mare-basalt fill obscuring their original melt sheets, so geochemical ties are indirect. Though the geological processes acting to vertically and laterally mix materials into regolith are the same as at the Apollo sites, the SPA interior is a fundamentally different geologic setting than the Apollo sites. The South Pole-Aitken basin was likely filled by a large impact melt sheet, possibly differentiated into cumulate horizons. It is on this distinctive melt sheet that the regolith has formed, somewhat diluting but not erasing the prominent geochemical signature seen from orbital assets. By analogy to the Apollo 16 site, a zeroth-order expectation is that bulk samples taken from regolith within SPA will contain abundant samples gardened from the SPA melt sheet. However, questions persist as to whether the SPA melt sheet has been so extensively contaminated with foreign ejecta that a simple robotic scoop sample of such regolith would be unlikely to yield the age of the basin.

  7. The radiation history of material returned by the Soviet automatic stations Luna 16 and Luna 20, according to track studies

    NASA Technical Reports Server (NTRS)

    Kashkarov, L. L.; Genayeva, L. I.; Lavrukhina, A. K.

    1977-01-01

    Fission tracks formed by the vH (very heavy) nuclei group of solar and galactic cosmic rays have been studied in silicate minerals of the lunar regolith returned by the Luna 16 and Luna 20 unmanned spacecraft. It is shown that the material in the Luna 16 core sample, from a typical mare region of the lunar surface, has undergone stronger irradiation by cosmic rays than material returned a highland region by Luna 20. A low-irradiation component (about 10 percent of the total number of crystals) has been found in the Luna 20 core sample materials, which can possibly be attributed to material added to the main bulk of the regolith in the formation of the crater Apollonius C. From the track density distribution of crystals, as a function of depth in the regolith core sample, it follows that the process of formation of the upper layer of the regolith, both for the lunar mare and for the highland region, includes sequential layering of finely crushed crystalline matter and subsequent mixing of it by micrometeorite bombardment. A portion of the crystals with a very high track density may be a component added to the lunar surface from outer space.

  8. Microwave Extraction of Water from Lunar Regolith Simulant

    NASA Technical Reports Server (NTRS)

    Ethridge, Edwin C.; Kaukler, William

    2007-01-01

    Nearly a decade ago the DOD Clementine lunar orbital mission obtained data indicating that the permanently shaded regions at the lunar poles may have permanently frozen water in the lunar soil. Currently NASA's Robotic Lunar Exploration Program, RLEP-2, is planned to land at the lunar pole to determine if water is present. The detection and extraction of water from the permanently frozen permafrost is an important goal for NASA. Extraction of water from lunar permafrost has a high priority in the In-Situ Resource Utilization, ISRU, community for human life support and as a fuel. The use of microwave processing would permit the extraction of water without the need to dig, drill, or excavate the lunar surface. Microwave heating of regolith is potentially faster and more efficient than any other heating methods due to the very low thermal conductivity of the lunar regolith. Also, microwaves can penetrate into the soil permitting water removal from deep below the lunar surface. A cryogenic vacuum test facility was developed for evaluating the use of microwave heating and water extraction from a lunar regolith permafrost simulant. Water is obtained in a cryogenic cold trap even with soil conditions below 0 C. The results of microwave extraction of water experiments will be presented.

  9. Regolith-atmosphere exchange of water in Mars' recent past

    NASA Astrophysics Data System (ADS)

    Steele, Liam J.; Balme, Matthew R.; Lewis, Stephen R.

    2017-03-01

    We investigate the exchange of water vapour between the regolith and atmosphere of Mars, and how it varies with different orbital parameters, atmospheric dust contents and surface water ice reservoirs. This is achieved through the coupling of a global circulation model (GCM) and a regolith diffusion model. GCM simulations are performed for hundreds of Mars years, with additional one-dimensional simulations performed for 50 kyr. At obliquities ɛ =15∘ and 30°, the thermal inertia and albedo of the regolith have more control on the subsurface water distribution than changes to the eccentricity or solar longitude of perihelion. At ɛ =45∘ , atmospheric water vapour abundances become much larger, allowing stable subsurface ice to form in the tropics and mid-latitudes. The circulation of the atmosphere is important in producing the subsurface water distribution, with increased water content in various locations due to vapour transport by topographically-steered flows and stationary waves. As these circulation patterns are due to topographic features, it is likely the same regions will also experience locally large amounts of subsurface water at different epochs. The dustiness of the atmosphere plays an important role in the distribution of subsurface water, with a dusty atmosphere resulting in a wetter water cycle and increased stability of subsurface ice deposits.

  10. Modeling the expected performance of the REgolith X-ray Imaging Spectrometer (REXIS)

    NASA Astrophysics Data System (ADS)

    Inamdar, Niraj K.; Binzel, Richard P.; Hong, Jae Sub; Allen, Branden; Grindlay, Jonathan; Masterson, Rebecca A.

    2014-09-01

    OSIRIS-REx is the third spacecraft in the NASA New Frontiers Program and is planned for launch in 2016. OSIRIS-REx will orbit the near-Earth asteroid (101955) Bennu, characterize it, and return a sample of the asteroid's regolith back to Earth. The Regolith X-ray Imaging Spectrometer (REXIS) is an instrument on OSIRIS-REx designed and built by students at MIT and Harvard. The purpose of REXIS is to collect and image sun-induced fluorescent X-rays emitted by Bennu, thereby providing spectroscopic information related to the elemental makeup of the asteroid regolith and the distribution of features over its surface. Telescopic reflectance spectra suggest a CI or CM chondrite analog meteorite class for Bennu, where this primitive nature strongly motivates its study. A number of factors, however, will influence the generation, measurement, and interpretation of the X-ray spectra measured by REXIS. These include: the compositional nature and heterogeneity of Bennu, the time-variable solar state, X-ray detector characteristics, and geometric parameters for the observations. In this paper, we will explore how these variables influence the precision to which REXIS can measure Bennu's surface composition. By modeling the aforementioned factors, we place bounds on the expected performance of REXIS and its ability to ultimately place Bennu in an analog meteorite class.

  11. Laboratory experiments to investigate sublimation rates of water ice in nighttime lunar regolith

    NASA Astrophysics Data System (ADS)

    Piquette, Marcus; Horányi, Mihály; Stern, S. Alan

    2017-09-01

    The existence of water ice on the lunar surface has been a long-standing topic with implications for both lunar science and in-situ resource utilization (ISRU). Cold traps on the lunar surface may have conditions necessary to retain water ice, but no laboratory experiments have been conducted to verify modeling results. We present an experiment testing the ability to thermally control bulk samples of lunar regolith simulant mixed with water ice under vacuum in an effort to constrain sublimation rates. The simulant used was JSC-1A lunar regolith simulant developed by NASA's Johnson Space Center. Samples with varying ratios of water ice and JSC-1A regolith simulant, totally about 1 kg, were placed under vacuum and cooled to 100 K to simulate conditions in lunar cold traps. The resulting sublimation of water ice over an approximately five-day period was measured by comparing the mass of the samples before and after the experimental run. Our results indicate that water ice in lunar cold traps is stable on timescales comparable to the lunar night, and should continue to be studied as possible resources for future utilization. This experiment also gauges the efficacy of the synthetic lunar atmosphere mission (SLAM) as a low-cost water resupply mission to lunar outposts.

  12. Instrument for Analysis of Organic Compounds on Other Planets

    NASA Technical Reports Server (NTRS)

    Daulton, Riley M.; Hintze, Paul E.

    2016-01-01

    The goal of this project is to develop the Instrument for Solvent Extraction and Analysis of Extraterrestrial Bodies using In Situ Resources (ISEE). Specifically, ISEE will extract and characterize organic compounds from regolith which is found on the surface of other planets or asteroids. The techniques this instrument will use are supercritical fluid extraction (SFE) and supercritical fluid chromatography (SFC). ISEE aligns with NASA's goal to expand the frontiers of knowledge, capability, and opportunities in space in addition to supporting NASA's aim to search for life elsewhere by characterizing organic compounds. The outcome of this project will be conceptual designs of 2 components of the ISEE instrument as well as the completion of proof-of-concept extraction experiments to demonstrate the capabilities of SFE. The first conceptual design is a pressure vessel to be used for the extraction of the organic compounds from the regolith. This includes a comparison of different materials, geometry's, and a proposition of how to insert the regolith into the vessel. The second conceptual design identifies commercially available fluid pumps based on the requirements needed to generate supercritical CO2. The proof-of-concept extraction results show the percent mass lost during standard solvent extractions of regolith with organic compounds. This data will be compared to SFE results to demonstrate the capabilities of ISEE's approach.

  13. Potential of derived lunar volatiles for life support

    NASA Technical Reports Server (NTRS)

    Bula, R. J.; Wittenberg, L. J.; Tibbitts, T. W.; Kulcinski, G. L.

    1992-01-01

    The lunar regolith contains small quantities of solar wind implanted volatile compounds that have vital, basic uses for maintaining life support systems of lunar or space settlements. Recent proposals to utilize the helium-3 isotope (He-3) derived from the lunar regolith as a fuel for fusion reactors would result in the availability of large quantities of other lunar volatile compounds. The quantities obtained would provide the annual life support replacement requirements of 1150 to 23,000 inhabitants per ton of He-3 recovered, depending on the volatile compound. Utilization of the lunar volatile compounds for life support depends on the costs, in terms of materials and energy, associated with their extraction from the lunar regolith as compared to the delivery costs of these compounds from Earth resources. Considering today's conservative estimated transportation costs ($10,000 dollars per kilogram) and regolith mining costs ($5 dollars per ton), the life support replacement requirements could be more economically supplied by recovering the lunar volatile compounds than transporting these materials from Earth resources, even before He-3 will be utilized as a fusion fuel. In addition, availability of lunar volatile compounds could have a significant cost impact on maintaining the life support systems of the space station and a Mars base.

  14. Maintaining the NA atmosphere of Mercury

    NASA Astrophysics Data System (ADS)

    Killen, R. M.; Morgan, T. H.

    1993-02-01

    The possible sources of the Na atmosphere of Mercury are calculatively studied. The likely structure, composition, and temperature of the planet's upper crust is examined along with the probable flux of Na from depth by grain boundary diffusion and by Knudsen flow. The creation of fresh regolith is considered along with mechanisms for supplying Na from the surface to the exosphere. The implications of the calculations for the probable abundances in the regolith are discussed.

  15. A constraint on impact theories of chondrule formation

    NASA Technical Reports Server (NTRS)

    Kerridge, J. F.; Kieffer, S. W.

    1977-01-01

    The association between agglutinates and chondrule-like spherules, which characterizes the assemblage of impact-derived melt products in lunar regolith samples and some gas-rich achondrites, is not found in primitive chondrites. This observation suggests that impacts into a parent-body regolith are unlikely to have produced the chondrules. We believe that if chondrules were formed from impact melt, it was probably generated by jetting during particle-to-particle collisions, presumably in the nebula.

  16. Lunar Water Resource Demonstration (LWRD)

    NASA Technical Reports Server (NTRS)

    Muscatello, Anthony C.

    2009-01-01

    Lunar Water Resource Demonstration (LWRD) is part of RESOLVE (Regolith and Environment Science & Oxygen and Lunar Volatile Extraction). RESOLVE is an ISRU ground demonstration: (1) A rover to explore a permanently shadowed crater at the south or north pole of the Moon (2) Drill core samples down to 1 meter (3) Heat the core samples to 150C (4) Analyze gases and capture water and/or hydrogen evolved (5) Use hydrogen reduction to extract oxygen from regolith

  17. Analysis of the ultrafine fraction of the Apollo 14 regolith

    NASA Technical Reports Server (NTRS)

    Finkelman, R. B.

    1973-01-01

    Analyses were obtained on more than 2400 randomly selected particles from the sub-37 micron (ultrafine) fraction of ten Apollo 14 regolith samples. The analyses were conducted with an energy dispersive electron microprobe system. The semiquantitative data were used to group the particles into ten categories. The pyroxene/plagioclase and olivine/plagioclase ratios are inconsistent with those ratios in the Apollo 14 breccias and rocks. The data suggest that fragmented basalts similar to Apollo 12 olivine basalts may have made significant contributions to the ultrafine fraction of the Fra Mauro regolith. Among a number of unusual particles encountered are brown, birefringent lath-shaped grains with 60 wt % SiO2 and 34 wt % FeO(FeSi2O5) and a glass with 20 to 25 wt % CaO, 0 to 8 wt % MgO, 40 to 45 wt % Al2O3 and approximately 30 wt % SiO2.

  18. Lunar base agriculture: Soils for plant growth

    NASA Technical Reports Server (NTRS)

    Ming, Douglas W. (Editor); Henninger, Donald L. (Editor)

    1989-01-01

    This work provides information on research and experimentation concerning various aspects of food production in space and particularly on the moon. Options for human settlement of the moon and Mars and strategies for a lunar base are discussed. The lunar environment, including the mineralogical and chemical properties of lunar regolith are investigated and chemical and physical considerations for a lunar-derived soil are considered. It is noted that biological considerations for such a soil include controlled-environment crop production, both hydroponic and lunar regolith-based; microorganisms and the growth of higher plants in lunar-derived soils; and the role of microbes to condition lunar regolith for plant cultivation. Current research in the controlled ecological life support system (CELSS) project is presented in detail and future research areas, such as the growth of higher research plants in CELSS are considered. Optimum plant and microbiological considerations for lunar derived soils are examined.

  19. Lunar oxygen production by pyrolysis of regolith

    NASA Technical Reports Server (NTRS)

    Senior, Constance L.

    1991-01-01

    Oxygen represents one of the most desirable products of lunar mining and manufacturing. Among the many processes which have been proposed for oxygen production, pyrolysis stands out as one which is uncomplicated and easy to bootstrap. Pyrolysis or vapor-phase reduction involves heating regolith to temperatures sufficient to allow partial decomposition and vaporization. Some metal oxides give up oxygen upon heating, either in the gas phase to form reduced gaseous species or in the condensed phase to form a metallic phase. Based on preliminary experiments and equilibrium calculations, the temperatures needed for pyrolysis are expected to be in the range of 2000 to 2200 K, giving total gas pressures of 0.001 to 0.1 torr. Bulk regolith can be used as a feedstock without beneficiation with concentrated solar radiation supplying most of energy needed. Further, selective condensation of metal-containing species from the gas phase may yield metallic iron and silicon as byproducts.

  20. Direct detection of projectile relics from the end of the lunar basin-forming epoch.

    PubMed

    Joy, Katherine H; Zolensky, Michael E; Nagashima, Kazuhide; Huss, Gary R; Ross, D Kent; McKay, David S; Kring, David A

    2012-06-15

    The lunar surface, a key proxy for the early Earth, contains relics of asteroids and comets that have pummeled terrestrial planetary surfaces. Surviving fragments of projectiles in the lunar regolith provide a direct measure of the types and thus the sources of exogenous material delivered to the Earth-Moon system. In ancient [>3.4 billion years ago (Ga)] regolith breccias from the Apollo 16 landing site, we located mineral and lithologic relics of magnesian chondrules from chondritic impactors. These ancient impactor fragments are not nearly as diverse as those found in younger (3.4 Ga to today) regolith breccias and soils from the Moon or that presently fall as meteorites to Earth. This suggests that primitive chondritic asteroids, originating from a similar source region, were common Earth-Moon-crossing impactors during the latter stages of the basin-forming epoch.

  1. Construction and Resource Utilization Explorer (CRUX): Implementing Instrument Suite Data Fusion to Characterize Regolith Hydrogen Resources

    NASA Technical Reports Server (NTRS)

    Haldemann, Albert F. C.; Johnson, Jerome B.; Elphic, Richard C.; Boynton, William V.; Wetzel, John

    2006-01-01

    CRUX is a modular suite of geophysical and borehole instruments combined with display and decision support system (MapperDSS) tools to characterize regolith resources, surface conditions, and geotechnical properties. CRUX is a NASA-funded Technology Maturation Program effort to provide enabling technology for Lunar and Planetary Surface Operations (LPSO). The MapperDSS uses data fusion methods with CRUX instruments, and other available data and models, to provide regolith properties information needed for LPSO that cannot be determined otherwise. We demonstrate the data fusion method by showing how it might be applied to characterize the distribution and form of hydrogen using a selection of CRUX instruments: Borehole Neutron Probe and Thermal Evolved Gas Analyzer data as a function of depth help interpret Surface Neutron Probe data to generate 3D information. Secondary information from other instruments along with physical models improves the hydrogen distribution characterization, enabling information products for operational decision-making.

  2. Grain-scale supercharging and breakdown on airless regoliths

    NASA Astrophysics Data System (ADS)

    Zimmerman, M. I.; Farrell, W. M.; Hartzell, C. M.; Wang, X.; Horanyi, M.; Hurley, D. M.; Hibbitts, K.

    2016-10-01

    Interactions of the solar wind and emitted photoelectrons with airless bodies have been studied extensively. However, the details of how charged particles interact with the regolith at the scale of a single grain have remained largely uncharacterized. Recent efforts have focused upon determining total surface charge under photoemission and solar wind bombardment and the associated electric field and potential. In this work, theory and simulations are used to show that grain-grain charge differences can exceed classical sheath predictions by several orders of magnitude, sometimes reaching dielectric breakdown levels. Temperature-dependent electrical conductivity works against supercharging by allowing current to leak through individual grains; the balance between internal conduction and surface charging controls the maximum possible grain-to-grain electric field. Understanding the finer details of regolith grain charging, conductive equilibrium, and dielectric breakdown will improve future numerical studies of space weathering and dust levitation on airless bodies.

  3. Small satellites

    NASA Technical Reports Server (NTRS)

    Thomas, P.; Veverka, J.; Dermott, S.

    1986-01-01

    Satellites smaller than Mimas (r = 195 km) are distinguished by irregular overall shapes and by rough limb topography. Material properties and impact cratering dominate the shaping of these objects. Long fragmentation histories can produce a variety of internal structures, but so far there is no direct evidence that any small satellite is an equilibrium ellipsoid made up of noncohesive gravitationally bound rubble. One many bodies that orbit close to their primary the tidal and rotational components of surface gravity strongly affect the directions of local g and thereby affect the redistribution of regolith by mass wasting. Downslope movement of regolith is extensive on Deimos, and is probably effective on many other small satellites. It is shown that in some cases observed patterns of downslope mass wasting cold produce useful constraints on the satellite's mean density. The diversity of features seen in the few high-resolution images of small satellites currently available suggests that these objects have undergone complex histories of cratering, fragmentation, and regolith evolution.

  4. Optimization of Crew Shielding Requirement in Reactor-Powered Lunar Surface Missions

    NASA Technical Reports Server (NTRS)

    Barghouty, Abdulnasser F.

    2007-01-01

    On the surface of the moon -and not only during heightened solar activities- the radiation environment As such that crew protection will be required for missions lasting in excess of six months. This study focuses on estimating the optimized crew shielding requirement for lunar surface missions with a nuclear option. Simple, transport-simulation based dose-depth relations of the three (galactic, solar, and fission) radiation sources am employed in a 1-dimensional optimization scheme. The scheme is developed to estimate the total required mass of lunar-regolith separating reactor from crew. The scheme was applied to both solar maximum and minimum conditions. It is shown that savings of up to 30% in regolith mass can be realized. It is argued, however, that inherent variation and uncertainty -mainly in lunar regolith attenuation properties in addition to the radiation quality factor- can easily defeat this and similar optimization schemes.

  5. Photometric anomalies in the Apollo landing sites as seen from the Lunar Reconnaissance Orbiter

    NASA Astrophysics Data System (ADS)

    Kaydash, Vadym; Shkuratov, Yuriy; Korokhin, Viktor; Videen, Gorden

    2011-01-01

    Phase-ratio imagery is a new tool of qualitative photometric analyses of the upper layer of the lunar regolith, which allows the identification of natural surface structure anomalies and artificially altered regolith. We apply phase-ratio imagery to analyze the Apollo-14, -15, and -17 landing sites. This reveals photometric anomalies of ˜170 × 120 m size that are characterized by lower values of the phase-function steepness, indicating a smoothing of the surface microstructure caused by the engine jets of the landing modules. Other photometric anomalies characterized by higher phase-function slopes are the result of regolith loosening by astronaut boots and the wheels of the Modular Equipment Transporter and the Lunar Roving Vehicle. We also provide a possible explanation for the high brightness of the wheel tracks seen in on-surface images acquired at very large phase angles.

  6. Extraction and Capture of Water from Martian Regolith Experimental Proof-of-Concept

    NASA Technical Reports Server (NTRS)

    Linne, Diane; Kleinhenz, Julie; Bauman, Steve; Johnson, Kyle

    2016-01-01

    Mars Design Reference Architecture 5.0:Lists in-situ resource utilization (ISRU) as enabling for robust human Mars missionsLO2LCH4 ascent propulsion 25,000 kg oxygen from atmosphere for ascent and life support Atmospheric based ISRU processes less operationally complex than surface based limited concept evaluation to date and Mars surface water property and distribution uncertainty would not allow [Mars soil water processing] to be base lined at this time Limited Concept Evaluation to Date Lunar regolith O2 extraction processing experience Lunar regolith is fluidized and heated to high temperatures with H2 to produce H2O from iron-bearing minerals Mars similarity concept: Soil placed in fluidized bed reactor Heated to moderate temperatures Inert gas flow used to fluidize the bed and help with water desorption Challenges: High-temperature dusty seals Working gas requires downstream separation and recycling to reduce consumables loss Batch process heating thermally inefficient.

  7. Optimization of Crew Shielding Requirement in Reactor-Powered Lunar Surface Missions

    NASA Technical Reports Server (NTRS)

    Barghouty, A. F.

    2007-01-01

    On the surface of the moon and not only during heightened solar activities the radiation environment is such that crew protection will be required for missions lasting in excess of six months. This study focuses on estimating the optimized crew shielding requirement for lunar surface missions with a nuclear option. Simple, transport-simulation based dose-depth relations of the three radiation sources (galactic, solar, and fission) are employed in a one-dimensional optimization scheme. The scheme is developed to estimate the total required mass of lunar regolith separating reactor from crew. The scheme was applied to both solar maximum and minimum conditions. It is shown that savings of up to 30% in regolith mass can be realized. It is argued, however, that inherent variation and uncertainty mainly in lunar regolith attenuation properties in addition to the radiation quality factor can easily defeat this and similar optimization schemes.

  8. Comparison of Direct Solar Energy to Resistance Heating for Carbothermal Reduction of Regolith

    NASA Technical Reports Server (NTRS)

    Muscatello, Anthony C.; Gustafson, Robert J.

    2011-01-01

    A comparison of two methods of delivering thermal energy to regolith for the carbo thermal reduction process has been performed. The comparison concludes that electrical resistance heating is superior to direct solar energy via solar concentrators for the following reasons: (1) the resistance heating method can process approximately 12 times as much regolith using the same amount of thermal energy as the direct solar energy method because of superior thermal insulation; (2) the resistance heating method is more adaptable to nearer-term robotic exploration precursor missions because it does not require a solar concentrator system; (3) crucible-based methods are more easily adapted to separation of iron metal and glass by-products than direct solar energy because the melt can be poured directly after processing instead of being remelted; and (4) even with projected improvements in the mass of solar concentrators, projected photovoltaic system masses are expected to be even lower.

  9. Experimental Measurements of Heat Transfer through a Lunar Regolith Simulant in a Vibro-Fluidized Reactor Oven

    NASA Technical Reports Server (NTRS)

    Nayagam, Vedha; Berger, Gordon M.; Sacksteder, Kurt R.; Paz, Aaron

    2012-01-01

    Extraction of mission consumable resources such as water and oxygen from the planetary environment provides valuable reduction in launch-mass and potentially extends the mission duration. Processing of lunar regolith for resource extraction necessarily involves heating and chemical reaction of solid material with processing gases. Vibrofluidization is known to produce effective mixing and control of flow within granular media. In this study we present experimental results for vibrofluidized heat transfer in lunar regolith simulants (JSC-1 and JSC-1A) heated up to 900 C. The results show that the simulant bed height has a significant influence on the vibration induced flow field and heat transfer rates. A taller bed height leads to a two-cell circulation pattern whereas a single-cell circulation was observed for a shorter height. Lessons learned from these test results should provide insight into efficient design of future robotic missions involving In-Situ Resource Utilization.

  10. Distribution and Origin of Amino Acids in Lunar Regolith Samples

    NASA Technical Reports Server (NTRS)

    Elsila, J. E.; Callahan, M. P.; Glavin, D. P.; Dworkin, J. P.; McLain, H. L.; Noble, S. K.; Gibson, E. K., Jr.

    2015-01-01

    The existence of organic compounds on the lunar surface has been a question of interest from the Apollo era to the present. Investigations of amino acids immediately after collection of lunar samples yielded inconclusive identifications, in part due to analytical limitations including insensitivity to certain compounds, an inability to separate enantiomers, and lack of compound-specific isotopic measurements. It was not possible to determine if the detected amino acids were indigenous to the lunar samples or the result of terrestrial contamination. Recently, we presented initial data from the analysis of amino acid abundances in 12 lunar regolith samples and discussed those results in the context of four potential amino acid sources [5]. Here, we expand on our previous work, focusing on amino acid abundances and distributions in seven regolith samples and presenting the first compound-specific carbon isotopic ratios measured for amino acids in a lunar sample.

  11. Characterization and Evaluation of Lunar Regolith and Simulants

    NASA Technical Reports Server (NTRS)

    Cross, William M.; Murphy, Gloria A.

    2010-01-01

    A NASA-ESMD (National Aeronautics and Space Administration-Exploration Systems Mission Directorate) funded senior design project "Mineral Separation Technology for Lunar Regolith Simulant Production" is directed toward designing processes to produce Simulant materials as close to lunar regolith as possible. The eight undergraduate (junior and senior) students involved are taking a systems engineering design approach to identifying the most pressing concerns in simulant needs, then designing subsystems and processing strategies to meet these needs using terrestrial materials. This allows the students to, not only learn the systems engineering design process, but also, to make a significant contribution to an important NASA ESMD project. This paper will primarily be focused on the implementation aspect, particularly related to the systems engineering process, of this NASA EMSD senior design project. In addition comparison of the NASA ESMD group experience to the implementation of systems engineering practices into a group of existing design projects is given.

  12. Microwave Sinterator Freeform Additive Construction System (MS-FACS)

    NASA Technical Reports Server (NTRS)

    Howe, Alan S.; Wilcox, Brian H.; Barmatz, Martin B.; Mercury, Michael B.; Siebert, Michael A.; Rieber, Richard R.

    2013-01-01

    The harmful properties of lunar dust, such as small size, glass composition, abnormal surface area, and coatings of imbedded nanophase iron, lead to a unique coupling of the dust with microwave radiation. This coupling can be exploited for rapid sintering of lunar soil for use as a construction material that can be formed to take on an infinite number of shapes and sizes. This work describes a system concept for building structures on the lunar surface using lunar regolith (soil). This system uses the ATHLETE (All-Terrain Hex- Limbed Extra-Terrestrial Explorer) mobility system as a positioning system with a microwave print head (similar to that of a smaller-scale 3D printer). A processing system delivers the lunar regolith to the microwave print head, where the microwave print head/chamber lays down a layer of melted regolith. An arm on the ATHLETE system positions the layer depending on the desired structure.

  13. Simulations of Effects of Nanophase Iron Space Weather Products on Lunar Regolith Reflectance Spectra

    NASA Astrophysics Data System (ADS)

    Escobar-Cerezo, J.; Penttilä, A.; Kohout, T.; Muñoz, O.; Moreno, F.; Muinonen, K.

    2018-01-01

    Lunar soil spectra differ from pulverized lunar rocks spectra by reddening and darkening effects, and shallower absorption bands. These effects have been described in the past as a consequence of space weathering. In this work, we focus on the effects of nanophase iron (npFe0) inclusions on the experimental reflectance spectra of lunar regolith particles. The reflectance spectra are computed using SIRIS3, a code that combines ray optics with radiative-transfer modeling to simulate light scattering by different types of scatterers. The imaginary part of the refractive index as a function of wavelength of immature lunar soil is derived by comparison with the measured spectra of the corresponding material. Furthermore, the effect of adding nanophase iron inclusions on the reflectance spectra is studied. The computed spectra qualitatively reproduce the observed effects of space weathered lunar regolith.

  14. Grain-Scale Supercharging and Breakdown on Airless Regoliths

    NASA Technical Reports Server (NTRS)

    Zimmerman, M. I.; Farrell, W. M.; Hartzell, C.M.; Wang, X.; Horanyi, M.; Hurley, D. M.; Hibbitts, K.

    2016-01-01

    Interactions of the solar wind and emitted photoelectrons with airless bodies have been studied extensively. However, the details of how charged particles interact with the regolith at the scale of a single grain have remained largely uncharacterized. Recent efforts have focused upon determining total surface charge under photoemission and solar wind bombardment and the associated electric field and potential. In this work, theory and simulations are used to show that grain-grain charge differences can exceed classical sheath predictions by several orders of magnitude, sometimes reaching dielectric breakdown levels. Temperature-dependent electrical conductivity works against supercharging by allowing current to leak through individual grains; the balance between internal conduction and surface charging controls the maximum possible grain-to-grain electric field. Understanding the finer details of regolith grain charging, conductive equilibrium, and dielectric breakdown will improve future numerical studies of space weathering and dust levitation on airless bodies.

  15. Combustion Joining of Regolith Tiles for In-Situ Fabrication of Launch/Landing Pads on the Moon and Mars

    NASA Technical Reports Server (NTRS)

    Ferguson, Robert E.; Shafirovich, Evgeny; Mantovani, James G.

    2017-01-01

    To mitigate dust problems during launch/landing operations in lunar and Mars missions, it is desired to build solid pads on the surface. Recently, strong tiles have been fabricated from lunar regolith simulants using high-temperature sintering. The present work investigates combustion joining of these tiles through the use of exothermic intermetallic reactions. Specifically, nickel/aluminum (1:1 mole ratio) mixture was placed in a gap between the tiles sintered from JSC-1A lunar regolith simulant. Upon ignition by a laser, a self-sustained propagation of the combustion front over the mixture occurred. Joining was improved with increasing the tile thickness from 6.3 mm to 12.7 mm. The temperatures sufficient for melting the glass phase of JSC-1A were recorded for 12.7-mm tiles, which explains the observed better joining.

  16. Combustion Joining of Regolith Tiles for In-Situ Fabrication of Launch/Landing Pads on the Moon and Mars

    NASA Technical Reports Server (NTRS)

    Ferguson, Robert E.; Mantovani, James G.; Shafirovich, Evgeny

    2017-01-01

    To mitigate dust problems during launch-landing operations in lunar and Mars missions, it is desired to build solid pads on the surface. Recently, strong tiles have been fabricated from lunar regolith simulants using high-temperature sintering. The present work investigates combustion joining of these tiles through the use of exothermic intermetallic reactions. Specifically, nickel aluminum (1:1 mole ratio) mixture was placed in a gap between the tiles sintered from JSC-1A lunar regolith simulant. Upon ignition by a laser, a self-sustained propagation of the combustion front over the mixture occurred. Joining was improved with increasing the tile thickness from 6.3 mm to 12.7 mm. The temperatures sufficient for melting the glass phase of JSC-1A were recorded for 12.7-mm tiles, which explains the observed better joining.

  17. Hydrogeology of, and simulation of ground-water flow in a mantled carbonate-rock system, Cumberland Valley, Pennsylvania

    USGS Publications Warehouse

    Chichester, D.C.

    1996-01-01

    The U.S. Geological Survey conducted a study in a highly productive and complex regolith-mantled carbonate valley in the northeastern part of the Cumberland Valley, Pa., as part of its Appalachian Valleys and Piedmont Regional Aquifer-system Analysis program. The study was designed to quantify the hydrogeologic characteristics and understand the ground-water flow system of a highly productive and complex thickly mantled carbonate valley. The Cumberland Valley is characterized by complexly folded and faulted carbonate bedrock in the valley bottom, by shale and graywacke to the north, and by red-sedimentary and diabase rocks in the east-southeast. Near the southern valley hillslope, the carbonate rock is overlain by wedge-shaped deposit of regolith, up to 450 feet thick, that is composed of residual material, alluvium, and colluvium. Locally, saturated regolith is greater than 200 feet thick. Seepage-run data indicate that stream reaches, near valley walls, are losing water from the stream, through the regolith, to the ground-water system. Results of hydrograph-separation analyses indicate that base flow in stream basins dominated by regolith-mantled carbonate rock, carbonate rock, and carbonate rock and shale are 81.6, 93.0, and 67.7 percent of total streamflow, respectively. The relative high percentage for the regolith-mantled carbonate-rock basin indicates that the regolith stores precipitation and slowly, steadily releases this water to the carbonate-rock aquifer and to streams as base flow. Anomalies in water-table gradients and configuration are a result of topography and differences in the character and distribution of overburden material, permeability, rock type, and geologic structure. Most ground-water flow is local, and ground water discharges to nearby springs and streams. Regional flow is northeastward to the Susquehanna River. Average-annual water budgets were calculated for the period of record from two continuous streamflow-gaging stations. Average-annual precipitation range from 39.0 to 40.5 inches, and averages about 40 inches for the model area. Average-annual recharge, which was assumed equal to the average-annual base flow, ranged from 12 inches for the Conodoguinet Creek, and 15 inches for the Yellow Breeches Creek. The thickly-mantled carbonate system was modeled as a three- dimensional water-table aquifer. Recharge to, ground-water flow through, and discharge from the Cumberland Valley were simulated. The model was calibrated for steady-state conditions using average recharge and discharge data. Aquifer horizontal hydraulic conductivity was calculated from specific-capacity data for each geologic unit in the area. Particle-tracking analyses indicate that interbasin and intrabasin flows of groundwater occur within the Yellow Breeches Creek Basin and between the Yellow Breeches and Conodoguinet Creek Basins.

  18. On the Relationship between the Apollo 16 Ancient Regolith Breccias and Feldspathic Fragmental Breccias, and the Composition of the Prebasin Crust in the Central Highlands of the Moon

    NASA Technical Reports Server (NTRS)

    Korotev, Randy L.

    1996-01-01

    Two types of texturally and compositionally similar breccias that consist largely of fragmental debris from meteorite impacts occur at the Apollo 16 lunar site: Feldspathic fragmental breccias (FFBS) and ancient regolith breccias (ARBs). Both types of breccia are composed of a suite of mostly feldspathic components derived from the early crust of the Moon and mafic impact-melt breccias produced during the time of basin formation. The ARBs also contain components, such as agglutinates and glass spherules, indicating that the material of which they are composed occurred at the surface of the Moon as fine-grained regolith prior to lithification of the breccias. These components are absent from the FFBS, suggesting that the FFBs might be the protolith of the ARBS. However, several compositional differences exist between the two types of breccia, making any simple genetic relationship implausible. First, clasts of mafic impact-melt breccia occurring in the FFBs are of a different composition than those in the ARBS. Also the feldspathic "prebasin" components of the FFBs have a lower average Mg/Fe ratio than the corresponding components of the ARBS; the average composition of the plagiociase in the FFBs is more sodic than that of the ARBS; and there are differences in relative abundances of rare earth elements. The two breccia types also have different provenances: the FFBs occur primarily in ejecta from North Ray crater and presumably derive from the Descartes Formation, while the ARBs are restricted to the Cayley plains. Together these observations suggest that although some type of fragmental breccia may have been a precursor to the ARBS, the FFBs of North Ray crater are not a significant component of the ARBs and, by inference, the Cayley plains. The average compositions of the prebasin components of the two types of fragmental breccia are generally similar to the composition of the feldspathic lunar meteorites. With 30-31% Al203, however, they are slightly richer in plagiociase than the most feldspathic lunar meteorites (approximately 29% Al203), implying that the crust of the early central nearside of the Moon contained a higher abundance of highly feldspathic anorthosite than typical lunar highlands, as inferred from the lunar meteorites. The ancient regolith breccias, as well as the current surface regolith ofthe Cayley plains, are more mafic than (1) prebasin regoliths in the Central Highlands and (2) regions of highlands presently distant from nearside basins because they contain a high abundance (approximately 30%) of mafic impact-melt breccias produced during the time of basin formation that is absent from other regoliths.

  19. Extrapolation of space weathering processes to other small solar system bodies

    NASA Astrophysics Data System (ADS)

    Gaffey, M. J.

    A diverse range of processes were invoked as the dominant factor or as important contributory factors in the modification of the optical surface and regolith of the moon. These include impact vitrification by large and small projectiles, solar wind implantation and the reduction of oxidized iron during energetic events, sputtering and crystal lattice damage by energetic cosmic rays, shock metamorphism of minerals, mixing of diverse lithologies by impacts, and contamination by external materials. These processes are also potentially important on the rocky surfaces of other small solar system bodies. For icy bodies, several additional processes are also possible, including formation of complex organic compounds from methane and ammonia-bearing ices by ultraviolet irradiation and the condensation of vapor species to form frost layers in the polar or cooler regions of objects at appropriate heliocentric distances. The lunar case, even when completely understood, will not extend in a simple linear fashion to other small rocky objects, nor will the optical surfaces of those objects all be affected to the same degree by each process. The major factors that will control the relative efficacy of a possible mechanism include the efficiency of ejecta retention and the degree to which the regolith materials experience multiple events (primarily a function of body size, escape velocity, and impactor velocities); the mean duration of typical regolith particle exposure at the optical surface and within reach of the micrometeorite, cosmic ray, solar wind, or UV fluxes (a function of the rate and scale of regolith mixing, production, and removal processes); the incident flux of solar (low energy) cosmic rays, solar wind, or UV radiation (inverse square of heliocentric distance) or of galactic (high energy) cosmic rays (slowly increasing flux with heliocentric distance); and the compositional and mineralogical nature of the surface being affected. In general, those processes that depend upon either the retention of impact ejecta or on the presence of multigenerational regoliths should be substantially less effective on smaller bodies with lower escape velocities. However, there are important exceptions to this generalization. For example, a process that involves the hypervelocity impact of small particles into a fine-grained regolith may be able to effectively retain highly shocked or melted material due to the nature of shock wave propagation in such a heterogeneous material.

  20. Extrapolation of space weathering processes to other small solar system bodies

    NASA Technical Reports Server (NTRS)

    Gaffey, M. J.

    1993-01-01

    A diverse range of processes were invoked as the dominant factor or as important contributory factors in the modification of the optical surface and regolith of the moon. These include impact vitrification by large and small projectiles, solar wind implantation and the reduction of oxidized iron during energetic events, sputtering and crystal lattice damage by energetic cosmic rays, shock metamorphism of minerals, mixing of diverse lithologies by impacts, and contamination by external materials. These processes are also potentially important on the rocky surfaces of other small solar system bodies. For icy bodies, several additional processes are also possible, including formation of complex organic compounds from methane and ammonia-bearing ices by ultraviolet irradiation and the condensation of vapor species to form frost layers in the polar or cooler regions of objects at appropriate heliocentric distances. The lunar case, even when completely understood, will not extend in a simple linear fashion to other small rocky objects, nor will the optical surfaces of those objects all be affected to the same degree by each process. The major factors that will control the relative efficacy of a possible mechanism include the efficiency of ejecta retention and the degree to which the regolith materials experience multiple events (primarily a function of body size, escape velocity, and impactor velocities); the mean duration of typical regolith particle exposure at the optical surface and within reach of the micrometeorite, cosmic ray, solar wind, or UV fluxes (a function of the rate and scale of regolith mixing, production, and removal processes); the incident flux of solar (low energy) cosmic rays, solar wind, or UV radiation (inverse square of heliocentric distance) or of galactic (high energy) cosmic rays (slowly increasing flux with heliocentric distance); and the compositional and mineralogical nature of the surface being affected. In general, those processes that depend upon either the retention of impact ejecta or on the presence of multigenerational regoliths should be substantially less effective on smaller bodies with lower escape velocities. However, there are important exceptions to this generalization. For example, a process that involves the hypervelocity impact of small particles into a fine-grained regolith may be able to effectively retain highly shocked or melted material due to the nature of shock wave propagation in such a heterogeneous material.

  1. Description and Analysis of Core Samples: The Lunar Experience

    NASA Technical Reports Server (NTRS)

    McKay, David S.; Allton, Judith H.

    1997-01-01

    Although no samples yet have been returned from a comet, extensive experience from sampling another solar system body, the Moon, does exist. While, in overall structure, composition, and physical properties the Moon bears little resemblance to what is expected for a comet, sampling the Moon has provided some basic lessons in how to do things which may be equally applicable to cometary samples. In particular, an extensive series of core samples has been taken on the Moon, and coring is the best way to sample a comet in three dimensions. Data from cores taken at 24 Apollo collection stations and 3 Luna sites have been used to provide insight into the evolution of the lunar regolith. It is now well understood that this regolith is very complex and reflects gardening (stirring of grains by micrometeorites), erosion (from impacts and solar wind sputtering), maturation (exposure on the bare lunar surface to solar winds ions and micrometeorite impacts) and comminution of coarse grains into finer grains, blanket deposition of coarse-grained layers, and other processes. All of these processes have been documented in cores. While a cometary regolith should not be expected to parallel in detail the lunar regolith, it is possible that the upper part of a cometary regolith may include textural, mineralogical, and chemical features which reflect the original accretion of the comet, including a form of gardening. Differences in relative velocities and gravitational attraction no doubt made this accretionary gardening qualitatively much different than the lunar version. Furthermore, at least some comets, depending on their orbits, have been subjected to impacts of the uppermost surface by small projectiles at some time in their history. Consequently, a more recent post-accretional gardening may have occurred. Finally, for comets which approach the sun, large scale erosion may have occurred driven by gas loss. The uppermost material of these comets may reflect some of the features of this erosional process, such as crust formation, and variations with depth might be expected. Overall, the upper few meters of a comet may be as complex in their own way as the upper few meters of the lunar regolith have proven to be, and by analogy, detailed studies of core samples containing this depth information will be needed to understand these processes and the details of the accretional history and the subsequent alteration history of comets.

  2. Nature of parent rocks, mineralization styles and ore genesis of regolith-hosted REE deposits in South China: An integrated genetic model

    NASA Astrophysics Data System (ADS)

    Li, Yan Hei Martin; Zhao, Wen Winston; Zhou, Mei-Fu

    2017-10-01

    Regolith-hosted rare earth element (REE) deposits, also called ion-adsorption or weathered crust elution-deposited REE deposits are distributed over Jiangxi, Guangdong, Fujian, Hunan, Guangxi and Yunnan provinces in South China. In general, these deposits can be categorized into the HREE-dominated type, for example the famous Zudong deposit in southern Jiangxi province and the LREE-dominated type, such as the Heling and Dingnan deposits in southern Jiangxi province. Most of these deposits form from weathering of biotite and muscovite granites, syenites, monzogranites, granodiorites, granite porphyries, and rhyolitic tuffs. The parent rocks are generally peraluminous, siliceous, alkaline and contain a variety of REE-bearing minerals. Mostly, REE patterns of regolith are inherited from the parent rocks, and therefore, characteristics of the parent rocks impose a significant control on the ore formation. Data compilation shows that autometasomatism during the latest stage of granite crystallization is likely essential in forming the HREE-enriched granites, whereas LREE-enriched granites could form through magmatic differentiation. These deposits are normally two- to three-fold, but could be up to ten-fold enrichment in REE compared to the parent granites, where the maximum enrichment usually occurs from the lower B to the upper C horizon. Ce shows different behavior with the other REEs. Strongly positive Ce anomalies commonly occur at the upper part of weathering profiles, likely due to oxidation of Ce3+ to Ce4+ and removal of Ce from soil solutions through precipitation of cerianite. Vertical pH and redox gradients in weathering crusts facilitate dissolution of REE-bearing minerals at shallow level and fixation of REE at depth through either adsorption on clay minerals or precipitation of secondary minerals. At the same time, mass removal of major elements plays an important role in concentrating REE in regolith. Combination of mass removal and eluviation-illuviation dynamics is the main mechanism for REE accumulation in weathering crusts. Favorable exogenetic factors facilitate the accumulation of REE in regolith and preservation of the ore bodies. These include quasi-equilibrium between denudation and exhumation at regional scales, local geomorphology dominated by low-lying gentle slopes, adequate rainfall, and favorable groundwater conditions. Continuous operation of such a dynamic weathering system is essential in the formation of regolith-hosted REE deposits.

  3. A Transmission Electron Microscope Investigation of Space Weathering Effects in Hayabusa Samples

    NASA Technical Reports Server (NTRS)

    Keller, Lindsay P.; Berger, Eve L.

    2014-01-01

    The Hayabusa mission to asteroid 25143 Itokawa successfully returned the first direct samples of the regolith from the surface of an asteroid. The Hayabusa samples thus present a special opportunity to directly investigate the evolution of asteroidal surfaces, from the development of the regolith to the study of the more complex effects of space weathering. Here we describe the mineralogy, microstructure and composition of three Hayabusa mission particles using transmission electron microscope (TEM) techniques

  4. Shock-treated Lunar Soil Simulant: Preliminary Assessment as a Construction Material

    NASA Technical Reports Server (NTRS)

    Boslough, Mark B.; Bernold, Leonhard E.; Horie, Yasuyuki

    1992-01-01

    In an effort to examine the feasibility of applying dynamic compaction techniques to fabricate construction materials from lunar regolith, preliminary explosive shock-loading experiments on lunar soil simulants were carried out. Analysis of our shock-treated samples suggests that binding additives, such as metallic aluminum powder, may provide the necessary characteristics to fabricate a strong and durable building material (lunar adobe) that takes advantage of a cheap base material available in abundance: lunar regolith.

  5. Preparation of a Frozen Regolith Simulant Bed for ISRU Component Testing in a Vacuum Chamber

    NASA Technical Reports Server (NTRS)

    Klenhenz, Julie; Linne, Diane

    2013-01-01

    In-Situ Resource Utilization (ISRU) systems and components have undergone extensive laboratory and field tests to expose hardware to relevant soil environments. The next step is to combine these soil environments with relevant pressure and temperature conditions. Previous testing has demonstrated how to incorporate large bins of unconsolidated lunar regolith into sufficiently sized vacuum chambers. In order to create appropriate depth dependent soil characteristics that are needed to test drilling operations for the lunar surface, the regolith simulant bed must by properly compacted and frozen. While small cryogenic simulant beds have been created for laboratory tests, this scale effort will allow testing of a full 1m drill which has been developed for a potential lunar prospector mission. Compacted bulk densities were measured at various moisture contents for GRC-3 and Chenobi regolith simulants. Vibrational compaction methods were compared with the previously used hammer compaction, or "Proctor", method. All testing was done per ASTM standard methods. A full 6.13 m3 simulant bed with 6 percent moisture by weight was prepared, compacted in layers, and frozen in a commercial freezer. Temperature and desiccation data was collected to determine logistics for preparation and transport of the simulant bed for thermal vacuum testing. Once in the vacuum facility, the simulant bed will be cryogenically frozen with liquid nitrogen. These cryogenic vacuum tests are underway, but results will not be included in this manuscript.

  6. Use of lunar regolith as a substrate for plant growth

    NASA Technical Reports Server (NTRS)

    Ming, D. W.; Henninger, D. L.

    1994-01-01

    Regenerative Life Support Systems (RLSS) will be required to regenerate air, water, and wastes, and to produce food for human consumption during long-duration missions to the Moon and Mars. It may be possible to supplement some of the materials needed for a lunar RLSS from resources on the Moon. Natural materials at the lunar surface may be used for a variety of lunar RLSS needs, including (1) soils or solid-support substrates for plant growth, (2) sources for extraction of essential, plant-growth nutrients, (3) substrates for microbial populations in the degradation of wastes, (4) sources of O2 and H2, which may be used to manufacture water, (5) feed stock materials for the synthesis of useful minerals (e.g., molecular sieves), and (6) shielding materials surrounding the outpost structure to protect humans, plants, and microorganisms from harmful radiation. Use of indigenous lunar regolith as a terrestrial-like soil for plant growth could offer a solid support substrate, buffering capacity, nutrient source/storage/retention capabilities, and should be relatively easy to maintain. The lunar regolith could, with a suitable microbial population, play a role in waste renovation; much like terrestrial waste application directly on soils. Issues associated with potentially toxic elements, pH, nutrient availability, air and fluid movement parameters, and cation exchange capacity of lunar regolith need to be addressed before lunar materials can be used effectively as soils for plant growth.

  7. Extraction of Water from Martian Regolith Simulant via Open Reactor Concept

    NASA Technical Reports Server (NTRS)

    Trunek, Andrew J.; Linne, Diane L.; Kleinhenz, Julie E.; Bauman, Steven W.

    2018-01-01

    To demonstrate proof of concept water extraction from simulated Martian regolith, an open reactor design is presented along with experimental results. The open reactor concept avoids sealing surfaces and complex moving parts. In an abrasive environment like the Martian surface, those reactor elements would be difficult to maintain and present a high probability of failure. A general lunar geotechnical simulant was modified by adding borax decahydrate (Na2B4O7·10H2O) (BDH) to mimic the 3 percent water content of hydrated salts in near surface soils on Mars. A rotating bucket wheel excavated the regolith from a source bin and deposited the material onto an inclined copper tray, which was fitted with heaters and a simple vibration system. The combination of vibration, tilt angle and heat was used to separate and expose as much regolith surface area as possible to liberate the water contained in the hydrated minerals, thereby increasing the efficiency of the system. The experiment was conducted in a vacuum system capable of maintaining a Martian like atmosphere. Evolved water vapor was directed to a condensing system using the ambient atmosphere as a sweep gas. The water vapor was condensed and measured. Processed simulant was captured in a collection bin and weighed in real time. The efficiency of the system was determined by comparing pre- and post-processing soil mass along with the volume of water captured.

  8. The Role of Planetary Dust and Regolith Mechanics in Technology Developments at NASA

    NASA Technical Reports Server (NTRS)

    Agui, Juan H.

    2011-01-01

    One of NASA's long term goals continues to be the exploration of other planets and orbital bodies in our solar system. Our sustained presence through the installation of stations or bases on these planetary surfaces will depend on developing properly designed habitation modules, mobility systems and supporting infrastructure. NASA Glenn Research Center is involved in several technology developments in support of this overarching goal. Two key developments are in the area of advanced filtration and excavation systems. The first addresses the issues posed by the accumulation of particulate matter over long duration missions and the intrusion of planetary dust into spacecraft and habitat pressurized cabins. The latter supports the operation and infrastructure of insitu resource utilization (ISRU) processes to derive consumables and construction materials from the planetary regolith. These two developments require a basic understanding of the lunar regolith at the micro (particle) to macro (bulk) level. Investigation of the relevant properties of the lunar regolith and characterization of the standard simulant materials used in. testing were important first steps in these developments. The fundamentals and operational concepts of these technologies as well as descriptions of new NASA facilities, including the Particulate Filtration Testing and the NASA Excavation and Traction Testing facilities, and their capabilities for testing and advancing these technologies will be presented. The test data also serves to validate and anchor computational simulation models.

  9. The Gulliver mission: Sample return from Deimos

    NASA Astrophysics Data System (ADS)

    Britt, D.

    The Martian moon Deimos has been accumulating material ejected from the Martian surface ever since the earliest periods of Martian history, over 4.4 Gyrs ago. Analysis of Martian ejecta, material accumulation, capture cross-section, regolith overturn, and Deimos's albedo suggest that Mars material may make up as much as 5-10% of Deimos's regolith. The Martian material on Deimos would be dominated by ejecta from the ancient crust of Mars, delivered during the Noachian Period of basin-forming impacts and heavy bombardment. Deimos is essentially a repository of samples from ancient Mars, which would include the full range of Martian crustal and upper mantle material from the early differentiation and crustal-forming epoch as well as samples from the era of high volatile flux, thick atmosphere, and possible surface water. The Gulliver Mission proposes to directly collect up to 10 kilograms of Deimos regolith and return it to Earth. This sample will contain up to 1000 grams of Martian material. Because of stochastic processes of regolith mixing over 4.4 Gyrs, the rock fragments, grains, and pebble-sized materials will likely sample the diversity of the Martian ancient surface. In addition to Martian ejecta, 90% of the Deimos sample will be spectral type D asteroidal material, thought to be highly primitive and originate in the outer asteroid belt. In essence, Gulliver represents two shortcuts, to Mars sample return and to the outer asteroid belt.

  10. Strata-1: An International Space Station Experiment into Fundamental Regolith Processes in Microgravity

    NASA Technical Reports Server (NTRS)

    Fries, M.; Abell, P.; Brisset, J.; Britt, D.; Colwell, J.; Durda, D.; Dove, A.; Graham, L.; Hartzell, C.; John, K.; hide

    2016-01-01

    The Strata-1 experiment will study the evolution of asteroidal regolith through long-duration exposure of simulant materials to the microgravity environment on the International Space Station (ISS). Many asteroids feature low bulk densities, which implies high values of porosity and a mechanical structure composed of loosely bound particles, (i.e. the "rubble pile" model), a prime example of a granular medium. Even the higher-density, mechanically coherent asteroids feature a significant surface layer of loose regolith. These bodies are subjected to a variety of forces and will evolve in response to very small perturbations such as micrometeoroid impacts, planetary flybys, and the YORP effect. Our understanding of this dynamical evolution and the inter-particle forces involved would benefit from long-term observations of granular materials exposed to small vibrations in microgravity. A detailed understanding of asteroid mechanical evolution is needed in order to predict the surface characteristics of as-of-yet unvisited bodies, to understand the larger context of samples collected by missions such as OSIRIS-REx and Hayabusa 1 and 2, and to mitigate risks for both manned and unmanned missions to asteroidal bodies. Understanding regolith dynamics will inform designs of how to land and set anchors, safely sample/move material on asteroidal surfaces, process large volumes of material for in situ resource utilization (ISRU) purposes, and, in general, predict behavior of large and small particles on disturbed asteroid surfaces.

  11. Geologic Conditions Required for the Fluvial Erosion of Titan’s Craters

    NASA Astrophysics Data System (ADS)

    Kinser, Rebeca; Neish, Catherine; Howard, Alan; Schenk, Paul; Bray, Veronica

    2015-11-01

    In comparison to other icy satellites, Titan has a small number of impact craters on its surface. This suggests that it has a young surface and/or erosional processes that remove craters from its surface. The set of geological conditions on Titan that would allow craters to become unrecognizable by orbiting spacecraft such as Cassini is unclear. Initial results suggest that not all geologic conditions would allow for complete degradation of impact craters on Titan. Using a landscape evolution model, we explored a larger parameter space to determine the conditions under which a representative 40 km crater on Titan would be eroded. We focused on varying the values of parameters such as bedrock and regolith erodibility, sediment grain size, the weathering rate of the regolith, and whether or not the regolith was saturated with liquid hydrocarbons. We found that only after changing the saturation state of the regolith mid-way through the simulation was it possible to completely erode the crater. Since there are few craters on Titan, this suggests that during Titan’s geological history there may have been varying quantities of liquid on its surface. Titan is known to have a dense atmosphere, not unlike that of the Earth, that could allow for surface liquids to vary under a changing climate. The erosion rate could then also vary as a direct result of changing climatic conditions.

  12. Technologies Enabling Scientific Exploration of Asteroids and Moons

    NASA Astrophysics Data System (ADS)

    Shaw, A.; Fulford, P.; Chappell, L.

    2016-12-01

    Scientific exploration of moons and asteroids is enabled by several key technologies that yield topographic information, allow excavation of subsurface materials, and allow delivery of higher-mass scientific payloads to moons and asteroids. These key technologies include lidar systems, robotics, and solar-electric propulsion spacecraft buses. Many of these technologies have applications for a variety of planetary targets. Lidar systems yield high-resolution shape models of asteroids and moons. These shape models can then be combined with radio science information to yield insight into density and internal structure. Further, lidar systems allow investigation of topographic surface features, large and small, which yields information on regolith properties. Robotic arms can be used for a variety of purposes, especially to support excavation, revealing subsurface material and acquiring material from depth for either in situ analysis or sample return. Robotic arms with built-in force sensors can also be used to gauge the strength of materials as a function of depth, yielding insight into regolith physical properties. Mobility systems allow scientific exploration of multiple sites, and also yield insight into regolith physical properties due to the interaction of wheels with regolith. High-power solar electric propulsion (SEP) spacecraft bus systems allow more science instruments to be included on missions given their ability to support greater payload mass. In addition, leveraging a cost-effective commercially-built SEP spacecraft bus can significantly reduce mission cost.

  13. Use of environmental tritium to characterize ground water flow systems in regolith and crystalline fractured-rock hydrogeologic settings

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stewart, L.M.; Rose, S.E.

    1993-03-01

    Environmental tritium concentrations measured in 84 ground-water, surface-water, and precipitation samples collected throughout the Piedmont and Blue Ridge physiographic provinces of northern Georgia were used in conjunction with available geological and hydrochemical data to develop general concepts of ground-water flow within a regolith and crystalline fractured-rock system. Tritium concentrations ranged from 0 tritium units (TU) in water sampled from unpumped wells completed in fractured bedrock to 34 TU in water sampled from pumped wells screened at various intervals within the overlying regolith. Tritium concentrations measured in spring discharge, streamflow, and precipitation also were within this range. The distribution of tritiummore » indicates that tritiated water is retained within the regolith and that pumping is an important mechanism for mixing water of different ages within the flow system. Simulations using an analytical mixing model were performed to estimate the degree of mixing and the residence time of ground water within the flow system. Results of the simulations compared favorably with other geological and hydrochemical data. Simulated residence times for tritiated water indicated that ground-water residence times may be greater than 37 years within the bedrock fractures, but as little as 15 years in pumped bedrock wells and streams. Estimates of ground-water ages were based on environmental tritium concentrations produced by thermonuclear bomb testing conducted during the years of 1961-1962.« less

  14. Crystal Stratigraphy of Two Basalts from Apollo 16: Unique Crystallization of Picritic Basalt 606063,10-16 and Very-Low-Titanium Basalt 65703,9-13

    NASA Technical Reports Server (NTRS)

    Donohue, P. H.; Neal, C. R.; Stevens, R. E.; Zeigler, R. A.

    2014-01-01

    A geochemical survey of Apollo 16 regolith fragments found five basaltic samples from among hundreds of 2-4 mm regolith fragments of the Apollo 16 site. These included a high-Ti vitrophyric basalt (60603,10-16) and one very-low-titanium (VLT) crystalline basalt (65703,9-13). Apollo 16 was the only highlands sample return mission distant from the maria (approx. 200 km). Identification of basaltic samples at the site not from the ancient regolith breccia indicates input of material via lateral transport by post-basin impacts. The presence of basaltic rocklets and glass at the site is not unprecedented and is required to satisfy mass-balance constraints of regolith compositions. However, preliminary characterization of olivine and plagioclase crystal size distributions indicated the sample textures were distinct from other known mare basalts, and instead had affinities to impact melt textures. Impact melt textures can appear qualitatively similar to pristine basalts, and quantitative analysis is required to distinguish between the two in thin section. The crystal stratigraphy method is a powerful tool in studying of igneous systems, utilizing geochemical analyses across minerals and textural analyses of phases. In particular, trace element signatures can aid in determining the ultimate origin of these samples and variations document subtle changes occurring during their petrogenesis.

  15. Robust and Elastic Lunar and Martian Structures from 3D-Printed Regolith Inks

    NASA Astrophysics Data System (ADS)

    Jakus, Adam E.; Koube, Katie D.; Geisendorfer, Nicholas R.; Shah, Ramille N.

    2017-03-01

    Here, we present a comprehensive approach for creating robust, elastic, designer Lunar and Martian regolith simulant (LRS and MRS, respectively) architectures using ambient condition, extrusion-based 3D-printing of regolith simulant inks. The LRS and MRS powders are characterized by distinct, highly inhomogeneous morphologies and sizes, where LRS powder particles are highly irregular and jagged and MRS powder particles are rough, but primarily rounded. The inks are synthesized via simple mixing of evaporant, surfactant, and plasticizer solvents, polylactic-co-glycolic acid (30% by solids volume), and regolith simulant powders (70% by solids volume). Both LRS and MRS inks exhibit similar rheological and 3D-printing characteristics, and can be 3D-printed at linear deposition rates of 1-150 mm/s using 300 μm to 1.4 cm-diameter nozzles. The resulting LRS and MRS 3D-printed materials exhibit similar, but distinct internal and external microstructures and material porosity (~20-40%). These microstructures contribute to the rubber-like quasi-static and cyclic mechanical properties of both materials, with young’s moduli ranging from 1.8 to 13.2 MPa and extension to failure exceeding 250% over a range of strain rates (10-1-102 min-1). Finally, we discuss the potential for LRS and MRS ink components to be reclaimed and recycled, as well as be synthesized in resource-limited, extraterrestrial environments.

  16. Differential rates of feldspar weathering in granitic regoliths

    USGS Publications Warehouse

    White, A.F.; Bullen, T.D.; Schulz, M.S.; Blum, A.E.; Huntington, T.G.; Peters, N.E.

    2001-01-01

    Differential rates of plagioclase and K-feldspar weathering commonly observed in bedrock and soil environments are examined in terms of chemical kinetic and solubility controls and hydrologic permeability. For the Panola regolith, in the Georgia Piedmont Province of southeastern United States, petrographic observations, coupled with elemental balances and 87Sr/86Sr ratios, indicate that plagioclase is being converted to kaolinite at depths > 6 m in the granitic bedrock. K-feldspar remains pristine in the bedrock but subsequently weathers to kaolinite at the overlying saprolite. In contrast, both plagioclase and K-feldspar remain stable in granitic bedrocks elsewhere in Piedmont Province, such as Davis Run, Virginia, where feldspars weather concurrently in an overlying thick saprolite sequence. Kinetic rate constants, mineral surface areas, and secondary hydraulic conductivities are fitted to feldspar losses with depth in the Panola and Davis Run regoliths using a time-depth computer spreadsheet model. The primary hydraulic conductivities, describing the rates of meteoric water penetration into the pristine granites, are assumed to be equal to the propagation rates of weathering fronts, which, based on cosmogenic isotope dating, are 7 m/106 yr for the Panola regolith and 4 m/106 yr for the Davis Run regolith. Best fits in the calculations indicate that the kinetic rate constants for plagioclase in both regoliths are factors of two to three times faster than K-feldspar, which is in agreement with experimental findings. However, the range for plagioclase and K-feldspar rates (kr = 1.5 x 10-17 to 2.8 x 10-16 mol m-2 s-1) is three to four orders of magnitude lower than for that for experimental feldspar dissolution rates and are among the slowest yet recorded for natural feldspar weathering. Such slow rates are attributed to the relatively old geomorphic ages of the Panola and Davis Run regoliths, implying that mineral surface reactivity decreases significantly with time. Differential feldspar weathering in the low-permeability Panola bedrock environment is more dependent on relative feldspar solubilities than on differences in kinetic reaction rates. Such weathering is very sensitive to primary and secondary hydraulic conductivities (qp and qs), which control both the fluid volumes passing through the regolith and the thermodynamic saturation of the feldspars. Bedrock permeability is primarily intragranular and is created by internal weathering of networks of interconnected plagioclase phenocrysts. Saprolite permeability is principally intergranular and is the result of dissolution of silicate phases during isovolumetric weathering. A secondary to primary hydraulic conductivity ratio of qs/qp = 150 in the Panola bedrock results in kinetically controlled plagioclase dissolution but thermodynamically inhibited K-feldspar reaction. This result is in accord with calculated chemical saturation states for groundwater sampled in the Panola Granite. In contrast, greater secondary conductivities in the Davis Run saprolite, qs/qp = 800, produces both kinetically controlled plagioclase and K-feldspar dissolution. Faster plagioclase reaction, leading to bedrock weathering in the Panola Granite but not at Davis Run, is attributed to a higher anorthite component of the plagioclase and a wetter and warmer climate. In addition, the Panola Granite has an abnormally high content of disseminated calcite, the dissolution of which precedes the plagioclase weathering front, thus creating additional secondary permeability. Copyright ?? 2001 Elsevier Science Ltd.

  17. Production of Oxygen from Lunar Regolith by Molten Oxide Electrolysis

    NASA Technical Reports Server (NTRS)

    Curreri, Peter A.

    2009-01-01

    This paper describes the use of the molten oxide electrolysis (MOE) process for the extraction of oxygen for life support and propellant, and silicon and metallic elements for use in fabrication on the Moon. The Moon is rich in mineral resources, but it is almost devoid of chemical reducing agents, therefore, molten oxide electrolysis is ideal for extraction, since the electron is the only practical reducing agent. MOE has several advantages over other extraction methods. First, electrolytic processing offers uncommon versatility in its insensitivity to feedstock composition. Secondly, oxide melts boast the twin key attributes of highest solubilizing capacity for regolith and lowest volatility of any candidate electrolytes. The former is critical in ensuring high productivity since cell current is limited by reactant solubility, while the latter simplifies cell design by obviating the need for a gas-tight reactor to contain evaporation losses as would be the case with a gas or liquid phase fluoride reagent operating at such high temperatures. Alternatively, MOE requires no import of consumable reagents (e.g. fluorine and carbon) as other processes do, and does not rely on interfacing multiple processes to obtain refined products. Electrolytic processing has the advantage of selectivity of reaction in the presence of a multi-component feed. Products from lunar regolith can be extracted in sequence according to the stabilities of their oxides as expressed by the values of the free energy of oxide formation (e.g. chromium, manganese, Fe, Si, Ti, Al, magnesium, and calcium). Previous work has demonstrated the viability of producing Fe and oxygen from oxide mixtures similar in composition to lunar regolith by molten oxide electrolysis (electrowinning), also called magma electrolysis having shown electrolytic extraction of Si from regolith simulant. This paper describes recent advances in demonstrating the MOE process by a joint project with participation by NASA KSC and MSFC, and Ohio State University and MIT. Progress in measuring cell efficiency for oxygen production, development of non reacting electrodes, and cell feeding and withdrawal will be discussed.

  18. High frequency thermal emission from the lunar surface and near surface temperature of the Moon from Chang’E-2 microwave radiometer

    NASA Astrophysics Data System (ADS)

    Fang, Tuo; Fa, Wenzhe

    2014-04-01

    Near surface temperature of the Moon and thermal behaviors of the lunar regolith can provide important information for constraining thermal and magmatic evolution models of the Moon and engineering constrains for in situ lunar exploration system. In this study, China’s Chang’E-2 (CE-2) microwave radiometer (MRM) data at high frequency channels are used to investigate near surface temperature of the Moon given the penetration ability of microwave into the desiccated and porous lunar regolith. Factors that affect high frequency brightness temperature (TB), such as surface slope, solar albedo and dielectric constant, are analyzed first using a revised Racca’s temperature model. Radiative transfer theory is then used to model thermal emission from a semi-infinite regolith medium, with considering dielectric constant and temperature profiles within the regolith layer. To decouple the effect of diurnal temperature variation in the uppermost lunar surface, diurnal averaged brightness temperatures at high frequency channels are used to invert mean diurnal surface and subsurface temperatures based on their bilinear profiles within the regolith layer. Our results show that, at the scale of the spatial resolution of CE-2 MRM, surface slope of crater wall varies typically from about 20° to 30°, and this causes a variation in TB about 10-15 K. Solar albedo can give rise to a TB difference of about 5-10 K between maria and highlands, whereas a ∼2-8 K difference can be compensated by the dielectric constant on the other hand. Inversion results indicate that latitude (ϕ) variations of the mean diurnal surface and subsurface temperatures follow simple rules as cos0.30ϕ and cos0.36ϕ, respectively. The inverted mean diurnal temperature profiles at the Apollo 15 and 17 landing sites are also compared with the Apollo heat flow experiment data, showing an inversion uncertainty <4 K for surface temperature and <1 K for subsurface temperature.

  19. An Analytical Model of Tribocharging in Regolith

    NASA Astrophysics Data System (ADS)

    Carter, D. P.; Hartzell, C. M.

    2015-12-01

    Nongravitational forces, including electrostatic forces and cohesion, can drive the behavior of regolith in low gravity environments such as the Moon and asteroids. Regolith is the 'skin' of solid planetary bodies: it is the outer coating that is observed by orbiters and the first material contacted by landers. Triboelectric charging, the phenomenon by which electrical charge accumulates during the collision or rubbing of two surfaces, has been found to occur in initially electrically neutral granular mixtures. Although charge transfer is often attributed to chemical differences between the different materials, charge separation has also been found to occur in mixtures containing grains of a single material, but with a variety of grain sizes. In such cases, the charge always separates according to grain size; typically the smaller grains acquire a more negative charge than the larger grains. Triboelectric charging may occur in a variety of planetary phenomena (including mass wasting and dust storms) as well as during spacecraft-surface interactions (including sample collection and wheel motion). Interactions between charged grains or with the solar wind plasma could produce regolith motion. However, a validated, predictive model of triboelectric charging between dielectric grains has not yet been developed. A model for such size-dependent charge separation will be presented, demonstrating how random collisions between initially electrically neutral grains lead to net migration of electrons toward the smaller grains. The model is applicable to a wide range of single-material granular mixtures, including those with unusual or wildly varying size distributions, and suggests a possible mechanism for the reversal of the usual size-dependent charge polarity described above. This is a significant improvement over existing charge exchange models, which are restricted to two discrete grains sizes and provide severely limited estimates for charge magnitude. We will also discuss the design of an experiment planned to test the charging estimates provided by the model presented and the potential implications for our understanding of regolith behavior.

  20. Development of a Modified Vacuum Cleaner for Lunar Surface Systems

    NASA Technical Reports Server (NTRS)

    Toon, Katherine P.; Lee, Steve A.; Edgerly, Rachel D.

    2009-01-01

    The National Aeronautics and Space Administration (NASA) mission to expand space exploration will return humans to the Moon with the goal of maintaining a long-term presence. One challenge that NASA will face returning to the Moon is managing the lunar regolith found on the Moon's surface, which will collect on extravehicular activity (EVA) suits and other equipment. Based on the Apollo experience, the issues astronauts encountered with lunar regolith included eye/lung irritation, and various hardware failures (seals, screw threads, electrical connectors and fabric contamination), which were all related to inadequate lunar regolith mitigation. A vacuum cleaner capable of detaching, transferring, and efficiently capturing lunar regolith has been proposed as a method to mitigate the lunar regolith problem in the habitable environment on lunar surface. In order to develop this vacuum, a modified "off-the-shelf" vacuum cleaner has been used to determine detachment efficiency, vacuum requirements, and optimal cleaning techniques to ensure efficient dust removal in habitable lunar surfaces, EVA spacesuits, and air exchange volume. During the initial development of the Lunar Surface System vacuum cleaner, systematic testing was performed with varying flow rates on multiple surfaces (fabrics and metallics), atmospheric (14.7 psia) and reduced pressures (10.2 and 8.3 psia), different vacuum tool attachments, and several vacuum cleaning techniques to determine the performance requirements for the vacuum cleaner. The data recorded during testing was evaluated by calculating percent removal, relative to the retained simulant on the tested surface. In addition, Scanning Electron Microscopy (SEM) imaging was used to determine particle size distribution retained on the surface. The scope of this paper is to explain the initial phase of vacuum cleaner development, including historical Apollo mission data, current state-of-the-art vacuum cleaner technology, and vacuum cleaner testing that has focused on detachment capabilities varying pressure environments.

  1. Development of a Modified Vacuum Cleaner for Lunar Surface Systems

    NASA Technical Reports Server (NTRS)

    Toon, Katherine P.; Lee, Steve A.; Edgerly, Rachel D.

    2010-01-01

    The National Aeronautics and Space Administration (NASA) mission to expand space exploration will return humans to the Moon with the goal of maintaining a long-term presence. One challenge that NASA will face returning to the Moon is managing the lunar regolith found on the Moon's surface, which will collect on extravehicular activity (EVA) suits and other equipment. Based on the Apollo experience, the issues astronauts encountered with lunar regolith included eye/lung irritation, and various hardware failures (seals, screw threads, electrical connectors and fabric contamination), which were all related to inadequate lunar regolith mitigation. A vacuum cleaner capable of detaching, transferring, and efficiently capturing lunar regolith has been proposed as a method to mitigate the lunar regolith problem in the habitable environment on lunar surface. In order to develop this vacuum, a modified "off-the-shelf' vacuum cleaner will be used to determine detachment efficiency, vacuum requirements, and optimal cleaning techniques to ensure efficient dust removal in habitable lunar surfaces, EVA spacesuits, and air exchange volume. During the initial development of the Lunar Surface System vacuum cleaner, systematic testing was performed with varying flow rates on multiple surfaces (fabrics and metallics), atmospheric (14.7 psia) and reduced pressures (10.2 and 8.3 psia), different vacuum tool attachments, and several vacuum cleaning techniques in order to determine the performance requirements for the vacuum cleaner. The data recorded during testing was evaluated by calculating particulate removal, relative to the retained simulant on the tested surface. In addition, optical microscopy was used to determine particle size distribution retained on the surface. The scope of this paper is to explain the initial phase of vacuum cleaner development, including historical Apollo mission data, current state-of-the-art vacuum cleaner technology, and vacuum cleaner testing that has focused on detachment capabilities at varying pressure environments.

  2. Global Surface Temperatures of the Moon

    NASA Astrophysics Data System (ADS)

    Williams, J. P.; Paige, D. A.; Greenhagen, B. T.; Sefton-Nash, E.

    2015-12-01

    The Diviner instrument aboard the Lunar Reconnaissance Orbiter (LRO) is providing the most comprehensive view of how regoliths on airless body store and exchange thermal energy with the space environment. Approximately a quarter trillion calibrated radiance measurements of the Moon, acquired over 5.5 years by Diviner, have been compiled into a 0.5° resolution global dataset with a 0.25 hour local time resolution. Maps generated with this dataset provide a global perspective of the surface energy balance of the Moon and reveal the complex and extreme nature of the lunar surface thermal environment. Daytime maximum temperatures are sensitive to the radiative properties of the surface and are ~387-397 K at the equator, dropping to ~95 K before sunrise. Asymmetry between the morning and afternoon temperatures is observed due to the thermal inertia of the regolith with the dusk terminator ~30 K warmer than the dawn terminator at the equator. An increase in albedo with incidence angle is required to explain the observed temperatures with latitude. At incidence angles >40° topography and surface roughness result in increasing anisothermality between spectral passbands and scatter in temperatures. Minimum temperatures reflect variations in thermophysical properties (Figure). Impact craters are found to modify regolith properties over large distances. The thermal signature of Tycho is asymmetric consistent with an oblique impact coming from the west. Some prominent crater rays are visible in the thermal data and require material with a higher thermal inertial than nominal regolith. The influence of the formation of the Orientale basin on the regolith properties is observable over a substantial portion of the western hemisphere despite its age (~3.8 Gyr), and may have contributed to mixing of highland and mare material on the southwest margin of Oceanus Procellarum where the gradient in radiative properties at the mare-highland contact are observed to be broad (~200 km).

  3. Regolith thermal property inversion in the LUNAR-A heat-flow experiment

    NASA Astrophysics Data System (ADS)

    Hagermann, A.; Tanaka, S.; Yoshida, S.; Fujimura, A.; Mizutani, H.

    2001-11-01

    In 2003, two penetrators of the LUNAR--A mission of ISAS will investigate the internal structure of the Moon by conducting seismic and heat--flow experiments. Heat-flow is the product of thermal gradient tial T / tial z, and thermal conductivity λ of the lunar regolith. For measuring the thermal conductivity (or dissusivity), each penetrator will carry five thermal property sensors, consisting of small disc heaters. The thermal response Ts(t) of the heater itself to the constant known power supply of approx. 50 mW serves as the data for the subsequent data interpretation. Horai et al. (1991) found a forward analytical solution to the problem of determining the thermal inertia λ ρ c of the regolith for constant thermal properties and a simplyfied geometry. In the inversion, the problem of deriving the unknown thermal properties of a medium from known heat sources and temperatures is an Identification Heat Conduction Problem (IDHCP), an ill--posed inverse problem. Assuming that thermal conductivity λ and heat capacity ρ c are linear functions of temperature (which is reasonable in most cases), one can apply a Kirchhoff transformation to linearize the heat conduction equation, which minimizes computing time. Then the error functional, i.e. the difference between the measured temperature response of the heater and the predicted temperature response, can be minimized, thus solving for thermal dissusivity κ = λ / (ρ c), wich will complete the set of parameters needed for a detailed description of thermal properties of the lunar regolith. Results of model calculations will be presented, in which synthetic data and calibration data are used to invert the unknown thermal diffusivity of the unknown medium by means of a modified Newton Method. Due to the ill-posedness of the problem, the number of parameters to be solved for should be limited. As the model calculations reveal, a homogeneous regolith allows for a fast and accurate inversion.

  4. Seismic Coupling of Short-Period Wind Noise Through Mars' Regolith for NASA's InSight Lander

    NASA Astrophysics Data System (ADS)

    Teanby, N. A.; Stevanović, J.; Wookey, J.; Murdoch, N.; Hurley, J.; Myhill, R.; Bowles, N. E.; Calcutt, S. B.; Pike, W. T.

    2017-10-01

    NASA's InSight lander will deploy a tripod-mounted seismometer package onto the surface of Mars in late 2018. Mars is expected to have lower seismic activity than the Earth, so minimisation of environmental seismic noise will be critical for maximising observations of seismicity and scientific return from the mission. Therefore, the seismometers will be protected by a Wind and Thermal Shield (WTS), also mounted on a tripod. Nevertheless, wind impinging on the WTS will cause vibration noise, which will be transmitted to the seismometers through the regolith (soil). Here we use a 1:1-scale model of the seismometer and WTS, combined with field testing at two analogue sites in Iceland, to determine the transfer coefficient between the two tripods and quantify the proportion of WTS vibration noise transmitted through the regolith to the seismometers. The analogue sites had median grain sizes in the range 0.3-1.0 mm, surface densities of 1.3-1.8 g cm^{-3}, and an effective regolith Young's modulus of 2.5^{+1.9}_{-1.4} MPa. At a seismic frequency of 5 Hz the measured transfer coefficients had values of 0.02-0.04 for the vertical component and 0.01-0.02 for the horizontal component. These values are 3-6 times lower than predicted by elastic theory and imply that at short periods the regolith displays significant anelastic behaviour. This will result in reduced short-period wind noise and increased signal-to-noise. We predict the noise induced by turbulent aerodynamic lift on the WTS at 5 Hz to be ˜2×10^{-10} ms^{-2} Hz^{-1/2} with a factor of 10 uncertainty. This is at least an order of magnitude lower than the InSight short-period seismometer noise floor of 10^{-8} ms^{-2} Hz^{-1/2}.

  5. An Investigation of the Mechanical Properties of Some Martian Regolith Simulants with Respect to the Surface Properties at the InSight Mission Landing Site

    NASA Astrophysics Data System (ADS)

    Delage, Pierre; Karakostas, Foivos; Dhemaied, Amine; Belmokhtar, Malik; Lognonné, Philippe; Golombek, Matt; De Laure, Emmanuel; Hurst, Ken; Dupla, Jean-Claude; Kedar, Sharon; Cui, Yu Jun; Banerdt, Bruce

    2017-10-01

    In support of the InSight mission in which two instruments (the SEIS seismometer and the HP3 heat flow probe) will interact directly with the regolith on the surface of Mars, a series of mechanical tests were conducted on three different regolith simulants to better understand the observations of the physical and mechanical parameters that will be derived from InSight. The mechanical data obtained were also compared to data on terrestrial sands. The density of the regolith strongly influences its mechanical properties, as determined from the data on terrestrial sands. The elastoplastic compression volume changes were investigated through oedometer tests that also provided estimates of possible changes in density with depth. The results of direct shear tests provided values of friction angles that were compared with that of a terrestrial sand, and an extrapolation to lower density provided a friction angle compatible with that estimated from previous observations on the surface of Mars. The importance of the contracting/dilating shear volume changes of sands on the dynamic penetration of the mole was determined, with penetration facilitated by the ˜1.3 Mg/m3 density estimated at the landing site. Seismic velocities, measured by means of piezoelectric bender elements in triaxial specimens submitted to various isotropic confining stresses, show the importance of the confining stress, with lesser influence of density changes under compression. A power law relation of velocity as a function of confining stress with an exponent of 0.3 was identified from the tests, allowing an estimate of the surface seismic velocity of 150 m/s. The effect on the seismic velocity of a 10% proportion of rock in the regolith was also studied. These data will be compared with in situ data measured by InSight after landing.

  6. Young Lunar Volcanic Features: Thermophysical Properties and Formation

    NASA Astrophysics Data System (ADS)

    Elder, C. M.; Hayne, P. O.; Donaldson Hanna, K. L.; Bandfield, J.; Ghent, R. R.; Williams, J. P.; Paige, D. A.

    2016-12-01

    Irregular Mare Patches (IMPs) are small features (100 - 5000 m) on the lunar nearside characterized by uneven terrain interspersed with topographically higher smooth terrain. Crater counting suggests that they are less than 100 Myr old [1, 2]. Several formation hypotheses have been proposed for IMPs, including: caldera collapse [3], explosive outgassing [2], lava flow inflation [4], pyroclastic eruption [5], and regolith drainage [6]. In this study, we use thermal infrared data from the Lunar Reconnaissance Orbiter (LRO) Diviner radiometer to investigate the thermophysical properties of the IMPs. We find that their average rock abundance is approximately a factor of two higher than the surrounding terrain. Comparison of Diviner data with thermal models rules out extensive competent rocks within 5-10 cm of the surface at the IMPs. We also derive the regolith thermal inertia [7] of the four largest IMPs. Sosigenes, Maskelyne, and Cauchy-5 have thermal inertias slightly higher than their surrounding terrain, likely due to the presence of small rocks surrounding nearby craters. Ina has an average thermal inertia lower than the surrounding terrain, and the only resolved smooth mound in Ina has an even lower thermal inertia which implies material that is less consolidated than typical regolith and/or contains fewer small rocks. Formation by lava flows or regolith drainage is not expected to result in material with a lower thermal inertia than pre-existing regolith, so in the case of at least Ina, some other process such as explosive outgassing or pyroclastic eruptions must have occurred. [1] Braden, S. et al. (2014) Nature Geo 7, 787-791. [2] Schultz, P. H. et al. (2006) Nature 444, 184-186. [3] El-Baz, F. (1973) Apollo 17: Preliminary Science Report 330, 30-13. [4] Garry, W. B. et al. (2012) JGR 117, E00H31. [5] Carter, L. B. et al. (2013) LPSC 44, 2146. [6] Qiao, L. et al. (2002) LPSC 47, 2002. [7] Vasavada, A. R. et al. (2012) JGR 117, E00H18.

  7. Nanoscale Compositional Relations in Lunar Rock Patina: Deciphering Sources for Patina Components on an Apollo 17 Station 6 Boulder

    NASA Technical Reports Server (NTRS)

    Christoffersen, R.; Noble, S. K.; Keller, L. P.

    2014-01-01

    Space weathering on the Moon and other airless bodies modifies the surfaces of regolith grains as well as the space-exposed surfaces of larger rocks and boulders. As space weathering witness plates, rocks and boulders are distinguished from regolith grains based on their ability to persist as physically intact substrates over longer time scales before being disaggregated by impact processes. Because lunar surfaces, including exposed rocks, quickly develop an optically thick layer of patina, it is important to understand the compositional relationship between patinas and their underlying rock substrates, particularly to support remote-sensing of rocky lunar terrains. Based on analytical TEM techniques, supported by focused ion beam (FIB) cross-sectioning, we have begun to systematize the multi-layer microstructural complexity of patinas on rock samples with a range of space exposure histories. Our on-going work has particularly focused on lunar rock 76015, both because it has a long (approx. 22 my) exposure history, and because its surface was exposed to patina development approximately 1 m off the regolith surface on a boulder in the Apollo 17 Station 6 boulder field. Potential sources for the 76015 patina therefore include impact-melted and vaporized material derived from the local rock substrate, as well as from the mix of large boulders and regolith in the Station 6 area. While similar, there are differences in the mineralogy and chemistry of the rocks and regolith at Station 6. We were interested to see if these, or other sources, could be distinguished in the average composition, as well as the compositional nanostratigraphy of the 76015 patina. To date we have acquired a total of 9 TEM FIB cross-sections from the 76015 patina, giving us reasonable confidence of being able to arrive at an integrated average for the patina major element composition based on analytical TEM methods.

  8. Plagioclase-Rich Itokawa Grains: Space Weathering, Exposure Ages, and Comparison to Lunar Soil Grains

    NASA Technical Reports Server (NTRS)

    Keller, L. P.; Berge, E.

    2017-01-01

    Regolith grains returned by the Hayabusa mission to asteroid 25143 Itokawa provide the only samples currently available to study the interaction of chondritic asteroidal material with the space weathering environment. Several studies have documented the surface alterations observed on the regolith grains, but most of these studies involved olivine because of its abundance. Here we focus on the rarer Itokawa plagioclase grains, in order to allow comparisons between Itokawa and lunar soil plagioclase grains for which an extensive data set exists.

  9. Eskolaite in the regolith of the Taurus-Littrow Valley

    NASA Astrophysics Data System (ADS)

    Mokhov, A. V.; Rybchuk, A. P.; Kartashov, P. M.; Gornostaeva, T. A.; Bogatikov, O. A.

    2017-08-01

    Eskolaite crystals were discovered in the course of Scanning Electron Microscopy (SEM) studies of the regolith sample, which was delivered from the continental area between Serenitatis and Tranquilitatis Maria during the Apollo 17 mission. The finding was compared with an analogue sampled from Mare Crisium (Luna 24 mission). A condensate-impact origin of eskolaite is assumed for both findings. It was demonstrated that the eskolaite of the Apollo 17 probe is genetically and morphologically identical to the eskolaite from the Luna 24 probes.

  10. Thermal Modeling on Planetary Regoliths

    NASA Technical Reports Server (NTRS)

    Hale, A. S.; Hapke, B.W.

    2002-01-01

    The thermal region of the spectrum is one of special interest in planetary science as it is the only region where planetary emission is significant. Studying how planetary surfaces emit in the thermal infrared can tell us about their physical makeup and chemical composition, as well as their temperature profile with depth. This abstract will discuss a model of thermal energy transfer in planetary regoliths on airless bodies which includes both conductive and radiative processes while including the time dependence of the solar input function.

  11. CO2: Adsorption on palagonite and the Martian regolith

    NASA Technical Reports Server (NTRS)

    Zent, Aaron P.; Fanale, Fraser P.; Postawko, Susan E.

    1987-01-01

    Possible scenarios for the evolution of the Martian climate are discussed. In the interest of determining an upper limit on the absorptive capacity of the Martian regolith, researchers examined the results of Fanale and Cannon (1971, 1974) for CO2 adsorption on nontronite and basalt. There appeared to be a strong proportionality between the capacity of the absorbent and its specific surface area. A model of the Martian climate is given that allows the researchers to make some estimates of exchangeable CO2 abundances.

  12. Determination of rare-earth elements in Luna 16 regolith sample by chemical spectral method

    NASA Technical Reports Server (NTRS)

    Stroganova, N. S.; Ryabukhin, V. A.; Laktinova, N. V.; Ageyeva, L. V.; Galkina, I. P.; Gatinskaya, N. G.; Yermakov, A. N.; Karyakin, A. V.

    1974-01-01

    An analysis was made of regolith from layer A of the Luna 16 sample for rare earth elements, by a chemical spectral method. Chemical and ion exchange concentrations were used to determine the content of 12 elements and Y at the level 0.001 to 0.0001 percent with 10 to 15 percent reproducibility of the emission determination. Results within the limits of reproducibility agree with data obtained by mass spectra, activation, and X-ray fluorescent methods.

  13. Asteroid, Lunar and Planetary Regolith Management A Layered Engineering Defense

    NASA Technical Reports Server (NTRS)

    Wagner, Sandra

    2014-01-01

    During missions on asteroid and lunar and planetary surfaces, space systems and crew health may be degraded by exposure to dust and dirt. Furthermore, for missions outside the Earth-Moon system, planetary protection must be considered in efforts to minimize forward and backward contamination. This paper presents an end-to-end approach to ensure system reliability, crew health, and planetary protection in regolith environments. It also recommends technology investments that would be required to implement this layered engineering defense.

  14. Surface Exposure Ages of Space-Weathered Grains from Asteroid 25143 Itokawa

    NASA Technical Reports Server (NTRS)

    Keller, L. P.; Berger, E. L.; Christoffersen, R.

    2015-01-01

    Space weathering processes such as solar wind ion irradiation and micrometeorite impacts are widely known to alter the properties of regolith materials exposed on airless bodies. The rates of space weathering processes however, are poorly constrained for asteroid regoliths, with recent estimates ranging over many orders of magnitude. The return of surface samples by JAXA's Hayabusa mission to asteroid 25143 Itokawa, and their laboratory analysis provides "ground truth" to anchor the timescales for space weathering processes on airless bodies.

  15. The record of Martian climatic history in cores and its preservation

    NASA Technical Reports Server (NTRS)

    Zent, A. P.

    1988-01-01

    Among the questions to be addressed by a Mars Sample Return Mission are the history of the Martian climate and the mechanisms that control the volatile cycles. Unfortunately, the evidence that bears most strongly on those issues lies in the volatile distribution in, and physical configuration of, a very delicate and volatile system: the uppermost Martian regolith. Some useful measurements to be made on returned samples of the regolith are identified, along with the many critical considerations in ensuring the usefulness of returned samples.

  16. Apollo 11 ilmenite revisited. [lunar resources of oxygen and water

    NASA Technical Reports Server (NTRS)

    Cameron, E. N.

    1992-01-01

    An account is given of the problems associated with beneficiation of the high-Ti regolith represented by Apollo 11's ilmenite sample. Magnetic and electrostatic separation, combined with sizing to reject all but the best fractions of the lunar regolith, will be essential; the production of high-grade ilmenite concentrates on the scale required for lunar oxygen production may still, however, be unachievable. These findings suggest that ilmenite production directly from high-Ti-content basalt may be a superior alternative.

  17. Stratigraphy of the Apollo 15 drill core

    NASA Technical Reports Server (NTRS)

    Heiken, G.; Duke, M.; Fryxell, R.; Nagle, J. S.; Scott, R.; Sellers, G. A.

    1972-01-01

    The crew of Apollo 15 collected at 242-centimeter-long core of the regolith of the moon developed on the surface of Palus Putredinis 3 deg 39 min 20 sec E, 26 deg 26 min 00 sec N. The 2.04-centimeter-diameter core, which has a mass of 1333.2 grams, consists of 42 major textural units, with thicknesses ranging from a few milliliters to 13 centimeters thick. The regolith is not homogeneous and is composed of many layers that are mostly ejecta from impact events.

  18. Systems engineering studies of lunar base construction

    NASA Technical Reports Server (NTRS)

    Morgenthaler, George W.

    1991-01-01

    Many ingenious concepts have been proposed for lunar base construction, but few systematic studies exist which relate time-consistent lunar base construction technologies and the choice of lunar base approach with the long-term SEI objectives - i.e., lunar indigenous base construction and Mars Exploration equipment development. To fill this gap, CSC has taken a two-pronged approach. First, the Center undertook basic geotechnical investigations of lunar soil, fabrication of a scale prototype of a lunar construction crane, a multi-robot construction team laboratory experiment, and a preliminary design of lunar base structures. Second, during Jun. and Jul. 1991 two lunar base construction systems engineering studies were accomplished - a 'near term lunar base' study, and a 'far-term lunar base' study. The goals of these studies were to define the major lunar base construction research problems in consistent technology/construction frameworks, and to define design requirements for construction equipment such as a lunar crane and a regolith mover. The 'near-term lunar base' study examined three different construction concepts for a lunar base comprised of pre-fabricated, pre-tested, Space Station Freedom-type modules, which would be covered with regolith shielding. Concept A used a lunar crane for unloading and transportation; concept B, a winch and cart; and concept C, a walker to move the modules from the landing site to the base site and assemble them. To evaluate the merits of each approach, calculations were made of mass efficiency measure, source mass, reliability, far-term base mass, Mars base mass, and base assembly time. The model thus established was also used to define the requirements for crane speed and regolith mover m(sup 3)/sec rates. A major problem addressed is how to 'mine' the regolith and stack it over the habitats as shielding. To identify when the cost of using indigenous lunar materials to construct the base exceeds the cost of development and delivery of the equipment for processing lunar materials, a study of construction of a candidate sintered regolith 'far term lunar base' was undertaken. A technique was devised for casting slabs of sintered (basaltic) regolith and assembling these into a hemispherical (or geodesic) dome. The major problem occurs with the inner liner. At 14.7 psi and 20 percent oxygen internal atmosphere, the entire structure is in tension, even with the regolith load. Also, another study has indicated that at 14.7 psi major resupply of air will be needed because of leakage, and astronauts may have to engage in extensive pre-breathing and post-breathing for extravehicular activity (EVA) tasks, thus detracting from useful mission work time. An alternative is to operate part of the base at, say, 5 psi and 70 percent oxygen, or to equip the astronauts with hard suits at 8.3 psi or greater. All of these choices directly influence base design and construction techniques.

  19. Lunar regolith densification

    NASA Technical Reports Server (NTRS)

    Ko, Hon-Yim; Sture, Stein

    1991-01-01

    Core tube samples of the lunar regolith obtained during the Apollo missions showed a rapid increase in the density of the regolith with depth. Various hypotheses have been proposed for the possible cause of this phenomenon, including the densification of the loose regolith material by repeated shaking from the seismic tremors which have been found to occur at regular monthly intervals when the moon and earth are closest to one another. A test bed was designed to study regolith densification. This test bed uses Minnesota Lunar Simulant (MLS) to conduct shaking experiments in the geotechnical centrifuge with an inflight shake table system. By reproducing realistic in-situ regolith properties, the experiment also serves to test penetrator concepts. The shake table system was designed and used for simulation experiments to study effects of earthquakes on terrestrial soil structures. It is mounted on a 15 g-ton geotechnical centrifuge in which the self-weight induced stresses are replicated by testing an n-th scale model in a gravity field which is n times larger than Earth's gravity. A similar concept applies when dealing with lunar prototypes, where the gravity ratio required for proper simulation of lunar gravity effects is that between the centrifugal acceleration and the lunar gravity. Records of lunar seismic tremors, or moonquakes, were obtained. While these records are being prepared for use as the input data to drive the shake table system, records from the El Centro earthquake of 1940 are being used to perform preliminary tests, using a soil container which was previously used for earthquake studies. This container has a laminar construction, with the layers free to slide on each other, so that the soil motion during the simulated earthquake will not be constrained by the otherwise rigid boundaries. The soil model is prepared by pluviating the MLS from a hopper into the laminar container to a depth of 6 in. The container is mounted on the shake table and the centrifuge is operated to generate an acceleration of 10 times Earth's gravity or 60 times the lunar gravity, thus simulating a lunar regolith thickness of 30 ft. The shake table is then operated using the scaled 'moonquake' as the input motion. One or more model moonquakes are used in each experiment, after which the soil is analyzed for its density profile with depth. This is accomplished by removing from the soil bed a column of soil contained within a thin rubber sleeve which has been previously embedded vertically in the soil during pluviation. This column of soil is transferred to a gamma ray device, in which the gamma ray transmission transversely through the soil is measured and compared with standard calibration samples. In this manner, the density profile can be determined. Preliminary results to date are encouraging, and the Center plans to study the effects of duration of shaking, intensity of the shaking motion, and the frequency of the motion.

  20. Lunar Contour Crafting: A Novel Technique for ISRU-Based Habitat Development

    NASA Technical Reports Server (NTRS)

    Khoshnevis, Behrokh; Bodiford, Melanie P.; Burks, Kevin H.; Ethridge, Ed; Tucker, Dennis; Kim, Won; Toutanji, Houssam; Fiske, Michael R.

    2004-01-01

    As the nation prepares to return to the Moon, it is apparent that the viability of long duration visits with appropriate radiation shielding/crew protection, hinges on the development of Lunar structures, preferably in advance of a manned landing, and preferably utilizing in-situ resources. Contour Crafting is a USC-patented technique for automated development of terrestrial concrete-based structures. The process is relatively fast, completely automated, and supports the incorporation of various infrastructure elements such as plumbing and electrical wiring. This paper will present a conceptual design of a Lunar Contour Crafting system designed to autonomously fabricate integrated structures on the Lunar surface using high-strength concrete based on Lunar regolith, including glass reinforcement rods or fibers fabricated from melted regolith. Design concepts will be presented, as well as results of initial tests aimed at concrete and glass production using Lunar regolith simulant. Key issues and concerns will be presented, along with design concepts for an LCC testbed to be developed at MSFC's Prototype Development Laboratory (PDL).

  1. Voxel Advanced Digital-Manufacturing for Earth and Regolith in Space Project

    NASA Technical Reports Server (NTRS)

    Zeitlin, Nancy; Mueller, Robert P.

    2015-01-01

    A voxel is a discrete three-dimensional (3D) element of material that is used to construct a larger 3D object. It is the 3D equivalent of a pixel. This project will conceptualize and study various approaches in order to develop a proof of concept 3D printing device that utilizes regolith as the material of the voxels. The goal is to develop a digital printer head capable of placing discrete self-aligning voxels in additive layers in order to fabricate small parts that can be given structural integrity through a post-printing sintering or other binding process. The quicker speeds possible with the voxel 3D printing approach along with the utilization of regolith material as the substrate will advance the use of this technology to applications for In-Situ Resource Utilization (ISRU), which is key to reducing logistics from Earth to Space, thus making long-duration human exploration missions to other celestial bodies more possible.

  2. An ISRU Propellant Production System to Fully Fuel a Mars Ascent Vehicle

    NASA Technical Reports Server (NTRS)

    Kleinhenz, Julie E.; Paz, Aaron

    2017-01-01

    In-Situ Resource Utilization (ISRU) will enable the long term presence of humans beyond low earth orbit. Since 2009, oxygen production from the Mars atmosphere has been baselined as an enabling technology for Mars human exploration by NASA. However, using water from the Martian regolith in addition to the atmospheric CO2 would enable the production of both liquid Methane and liquid Oxygen, thus fully fueling a Mars return vehicle. A case study was performed to show how ISRU can support NASA's Evolvable Mars Campaign (EMC) using methane and oxygen production from Mars resources. A model was built and used to generate mass and power estimates of an end-to-end ISRU system including excavation and extraction water from Mars regolith, processing the Mars atmosphere, and liquefying the propellants. Even using the lowest yield regolith, a full ISRU system would weigh 1.7 mT while eliminating the need to transport 30 mT of ascent propellants from earth.

  3. JSC-1: A new lunar regolith simulant

    NASA Technical Reports Server (NTRS)

    Mckay, David S.; Carter, James L.; Boles, Walter W.; Allen, Carlton C.; Allton, Judith H.

    1993-01-01

    Simulants of lunar rocks and soils with appropriate properties, although difficult to produce in some cases, will be essential to meeting the system requirements for lunar exploration. In order to address this need a new lunar regolith simulant, JSC-1, has been developed. JSC-1 is a glass-rich basaltic ash which approximates the bulk chemical composition and mineralogy of some lunar soils. It has been ground to produce a gain size distribution approximating that of lunar regolith samples. The simulant is available in large quantities (greater than 2000 lb; 907 kg). JSC-1 was produced specifically for large- and medium-scale engineering studies in support of future human activities on the Moon. Such studies include material handling, construction, excavation, and transportation. The simulant is also appropriate for research on dust control and spacesuit durability. JSC-1 can be used as a chemical or mineralogical analog to some lunar soils for resource studies such as oxygen or metal production, sintering, and radiation shielding.

  4. Silicon PV cell production on the Moon as the basis for a new architecture for space exploration

    NASA Astrophysics Data System (ADS)

    Duke, Michael B.; Ignatiev, Alex; Freundlich, Alex; Rosenberg, Sanders D.; Makel, Darby

    2001-02-01

    A method is described by which silicon photovoltaic (PV) devices can be directly deposited onto the lunar regolith using primarily lunar materials. In sequence, a robotic ``crawler'' moving at slow speed sequentially melts the top layer of regolith and deposits a conducting layer, a doped silicon, a top conducting grid, and an antireflective coating by vacuum evaporation techniques. Concentrated solar energy is utilized as the energy source. Development of this capability would significantly lower the cost of electrical energy on the Moon and would enable a range of other activities, including lower cost propellant production, human outposts with complete food-growth capabilities, and advanced materials production. Low cost energy could affect the economics of propellants in space by allowing the extraction of solar wind hydrogen from the lunar regolith. This would allow the economical export of propellants and other materials to space, first to an Earth-Moon Lagrangian Point and potentially to low Earth orbit. .

  5. Measurements of Shock Effects Recorded by Hayabusa Samples

    NASA Technical Reports Server (NTRS)

    Zolensky, Michael; Mikouchi, Takashi; Hagiya, Kenji; Ohsumi, Kazumasa; Martinez, James; Komatsu, Mutsumi; Chan, Queenie H-.S.

    2015-01-01

    We requested and have been approved for 5 Hayabusa samples in order definitively establish the degree of shock experienced by the regolith of asteroid Itokawa, and to devise a bridge between shock determinations by standard light optical petrography, crystal structures as determined by synchrotron X-ray diffraction (SXRD), and degree of crystallinity as determined by electron back-scattered diffraction (EBSD) [1,2]. As of the writing of this abstract we are awaiting the approved samples. We propose measurements of astromaterial crystal structures and regolith processes. The proposed research work will improve our understanding of how small, primitive solar system bodies formed and evolved, and improve understanding of the processes that determine the history and future of habitability of environments on other solar system bodies. The results of the proposed research will directly enrich the ongoing asteroid and comet exploration missions by NASA, JAXA and ESA, and broaden our understanding of the origin and evolution of small bodies in the early solar system, and elucidate the nature of asteroid and comet regolith.

  6. Measurements of Shock Effects Recorded by Itokawa Samples

    NASA Technical Reports Server (NTRS)

    Zolensky, Michael; Mikouchi, Takashi; Hagiya, Kenji; Ohsumi, Kazumasa; Martinez, James; Komatsu, Mutsumi; Chan, Queenie H-.S.

    2016-01-01

    We requested and have been approved for 5 Hayabusa samples in order definitively establish the degree of shock experienced by the regolith of asteroid Itokawa, and to devise a bridge between shock determinations by standard light optical petrography, crystal structures as determined by synchrotron X-ray diffraction (SXRD), and degree of crystallinity as determined by electron back-scattered diffraction (EBSD). As of the writing of this abstract we are awaiting the approved samples. We propose measurements of astromaterial crystal structures and regolith processes. The proposed research work will improve our understanding of how small, primitive solar system bodies formed and evolved, and improve understanding of the processes that determine the history and future of habitability of environments on other solar system bodies. The results of the proposed research will directly enrich the ongoing asteroid and comet exploration missions by NASA, JAXA and ESA, and broaden our understanding of the origin and evolution of small bodies in the early solar system, and elucidate the nature of asteroid and comet regolith.

  7. Evaluation of Tribocharged Electrostatic Beneficiation of Lunar Simulant in Lunar Gravity

    NASA Technical Reports Server (NTRS)

    Quinn, Jacqueline W.; Captain, Jim G.; Weis, Kyle; Santiago-Maldonado, Edgardo; Trigwell, Steve

    2011-01-01

    The lunar regolith has high concentrations of aluminum, silicon, calcium, iron, sodium, and titanium oxides. Liberation of these metals would provide necessary materials for structural and building material fabrication, spare part, machine and tool production, and construction and site preparation in-situ on the moon or other extraterrestrial body (Rao et al 1979). Ilmenite (FeTi03) is a mineral of interest on the moon as a source of iron, titanium, and oxygen (Cameron 1992, Zhao and Shadman 1993) and therefore enrichment of this mineral in the feedstock before processing would be a considerable advantage in reducing energy requirements to process regolith. Not only for construction materials, but shipping oxygen and water from earth is weight prohibitive, and so investigations into the potential production of oxygen from the oxides of lunar regolith are a major research initiative by NASA (Sibille et al. 2009, Moscatello et al. 2009). In this paper, the results of electrostatic beneficiation of two sets of lunar simulants on two different reduced gravity flight series are presented.

  8. Resources for a lunar base: Rocks, minerals, and soil of the Moon

    NASA Technical Reports Server (NTRS)

    Taylor, Lawrence A.

    1992-01-01

    The rocks and minerals of the Moon will be included among the raw materials used to construct a lunar base. The lunar regolith, the fragmental material present on the surface of the Moon, is composed mostly of disaggregated rocks and minerals, but also includes glassy fragments fused together by meteorite impacts. The finer fraction of the regolith (i.e., less than 1 cm) is informally referred to as soil. The soil is probably the most important portion of the regolith for use at a lunar base. For example, soil can be used as insulation against cosmic rays, for lunar ceramics and abodes, or for growing plants. The soil contains abundant solar-wind-implanted elements as well as various minerals, particularly oxide phases, that are of potential economic importance. For example, these components of the soil are sources of oxygen and hydrogen for rocket fuel, helium for nuclear energy, and metals such as Fe, Al, Si, and Ti.

  9. Employing ISRU Models to Improve Hardware Design

    NASA Technical Reports Server (NTRS)

    Linne, Diane L.

    2010-01-01

    An analytical model for hydrogen reduction of regolith was used to investigate the effects of several key variables on the energy and mass performance of reactors for a lunar in-situ resource utilization oxygen production plant. Reactor geometry, reaction time, number of reactors, heat recuperation, heat loss, and operating pressure were all studied to guide hardware designers who are developing future prototype reactors. The effects of heat recuperation where the incoming regolith is pre-heated by the hot spent regolith before transfer was also investigated for the first time. In general, longer reaction times per batch provide a lower overall energy, but also result in larger and heavier reactors. Three reactors with long heat-up times results in similar energy requirements as a two-reactor system with all other parameters the same. Three reactors with heat recuperation results in energy reductions of 20 to 40 percent compared to a three-reactor system with no heat recuperation. Increasing operating pressure can provide similar energy reductions as heat recuperation for the same reaction times.

  10. Some consequences of a liquid water saturated regolith in early Martian history

    NASA Technical Reports Server (NTRS)

    Fuller, A. O.; Hargraves, R. B.

    1978-01-01

    Flooding of low-lying areas of the Martian regolith may have occurred early in the planet's history when a comparatively dense primitive atmosphere existed. If this model is valid, the following are some pedogenic and mineralogical consequences to be expected. Fluctuation of the water table in response to any seasonal or longer term causes would have resulted in precipitation of ferric oxyhydroxides with the development of a vesicular duricrust (or hardpan). Disruption of such a crust by scarp undercutting or frost heaving accompanied by wind deflation of fines could account for the boulders visible on Utopia Planitia in the vicinity of the second Viking lander site. Laboratory and field evidence on earth suggests that under weakly oxidizing conditions lepidocrocite (rather than goethite) would have preferentially formed in the Martian regolith from the weathering of ferrous silicates, accompanied by montmorillonite, nontronite, and cronstedtite. Maghemite may have formed as a low-temperature dehydrate of lepidocrocite or directly from ferrous precursors.

  11. Test Before You Fly - High Fidelity Planetary Environment Simulation

    NASA Technical Reports Server (NTRS)

    Craven, Paul; Ramachandran, Narayanan; Vaughn, Jason; Schneider, Todd; Nehls, Mary

    2012-01-01

    The lunar surface environment will present many challenges to the survivability of systems developed for long duration lunar habitation and exploration of the lunar, or any other planetary, surface. Obstacles will include issues pertaining especially to the radiation environment (solar plasma and electromagnetic radiation) and lunar regolith dust. The Planetary Environments Chamber is one piece of the MSFC capability in Space Environmental Effects Test and Analysis. Comprised of many unique test systems, MSFC has the most complete set of SEE test capabilities in one location allowing examination of combined space environmental effects without transporting already degraded, potentially fragile samples over long distances between tests. With this system, the individual and combined effects of the lunar radiation and regolith environment on materials, sub-systems, and small systems developed for the lunar return can be investigated. This combined environments facility represents a unique capability to NASA, in which tests can be tailored to any one aspect of the lunar environment (radiation, temperature, vacuum, regolith) or to several of them combined in a single test.

  12. High resolution space photometry as a method to reveal structure anomalies of the lunar surface

    NASA Astrophysics Data System (ADS)

    Kaydash, V. G.; Shkuratov, Yu. G.; Korokhin, V. V.

    2015-11-01

    We have reviewed studies of disturbed primordial structure of the lunar regolith, which is caused by both artificial and natural factors. To identify such disturbances, we used orbital high resolution photometry data in conjunction with the method of phase ratios, which makes it possible to evaluate the surface roughness of the light scattering element on the scale of less than imaging resolution. In particular, this method allows the identification of soil talus; it is also an efficient way to find new craters and places of falling meteoroid streams. The reliability of the new method is proved by the photometric detection of the anomalies associated with changes in the structure of the surface layer of regolith in landing sites of manned spacecraft, i.e., where the impact of human activity on the lunar regolith is well known. The results can be used in a planning and implementation of space missions to the Moon and other atmosphereless bodies of the solar system by the space agencies

  13. Ferromagnetic resonance studies of lunar core stratigraphy

    NASA Technical Reports Server (NTRS)

    Housley, R. M.; Cirlin, E. H.; Goldberg, I. B.; Crowe, H.

    1976-01-01

    We first review the evidence which links the characteristic ferromagnetic resonance observed in lunar fines samples with agglutinatic glass produced primarily by micrometeorite impacts and present new results on Apollo 15, 16, and 17 breccias which support this link by showing that only regolith breccias contribute significantly to the characteristic FMR intensity. We then provide a calibration of the amount of Fe metal in the form of uniformly magnetized spheres required to give our observed FMR intensities and discuss the theoretical magnetic behavior to be expected of Fe spheres as a function of size. Finally, we present FMR results on samples from every 5 mm interval in the core segments 60003, 60009, and 70009. These results lead us to suggest: (1) that secondary mixing may generally be extensive during regolith deposition so that buried regolith surfaces are hard to recognize or define; and (2) that local grinding of rocks and pebbles during deposition may lead to short scale fluctuations in grain size, composition, and apparent exposure age of samples.

  14. A Survey of Geologic Resources. Chapter 11

    NASA Technical Reports Server (NTRS)

    Edmonson, Jennifer; Rickman, Doug

    2012-01-01

    This chapter focuses on the resources available from the Moon itself: regolith, geologically concentrated materials, and lunar physical features that will enable habitation and generation of power on the surface. This chapter briefly covers the formation of the Moon and thus the formation of the crust of the Moon, as well as the evolution of the regolith. The characteristics of the regolith are provided in some detail, including its mineralogy and lithology. The location of high concentrations of specific minerals or rocks is noted. Other ideal locations for in situ resource utilization technology and lunar habitation are presented. This chapter is intended to be a brief review of current knowledge, and to serve as a foundational source for further study. Each concept presented here has a wealth of literature associated with it; the reader is therefore directed to that literature with each discussion. With great interest in possible manned lunar landings and continued study of the Moon by multiple satellites, the available information changes regularly.

  15. Some Expected Mechanical Characteristics of Lunar Dust: A Geological View

    NASA Technical Reports Server (NTRS)

    Rickman, Doug; Street, Kenneth W.

    2008-01-01

    The engineering properties of the lunar regolith reflect aspects of the original parent rock and the consequences of hypervelocity meteor bombardment. Compared to the Earth the geologic nature of the lunar regolith is quite distinct. On scales relevant to machinery, heterogeneity with respect to size and composition is much higher. But the total range in composition is much more restricted. Both facts have implications for predictions of properties, such as abrasion, which will be required by design engineers for constructing equipment for lunar use. Abrasion is related to hardness and hardness is a commonly measured property for both minerals and engineering materials. Although different hardness scales are routinely employed for minerals and engineering materials, a significant amount of literature is available relating the two. In this paper we discuss how to relate hardness to abrasion for the design of lunar equipment. We also indicate how abundant the various mineral phases are and typical size distributions for lunar regolith.

  16. Volatilization and mixing in glasses of some Apollo 14 regolith breccias

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vaniman, D.T.; Heiken, G.H.

    1989-01-01

    Three unique samples can be distinguished by analysis of all glass types, including devitrified glasses, in a suite of 26 Apollo 14 regolith breccias. These unique samples include the well-studied sample 14315, which has an abundance of anorthositic gabbro glasses and devitrified glasses; 14004,77, which has no glasses other than those that match the local soil; and 14076,5, which contains no glasses similar to the local soil or to LKFM. Sample 14076,5 is clearly exotic, for it contains devitrified glasses of anorthositic composition and of a silica-volatilized (HASP) trend that stems from anorthosite; these silica-volatilized glasses contain the new mineralmore » yoshiokite. HASP glasses in this exotic sample and HASP glass spheres that stem from the Apollo 14 soil composition differ greatly from the HASP glasses at Apollo 16. The various HASP glasses can be just as useful as non-volatilized glasses in searching or major crustal or regolith lithologies. 18 refs., 2 figs., 2 tabs.« less

  17. Electrostatic Beneficiation of Lunar Regolith: Applications in In-Situ Resource Utilization

    NASA Technical Reports Server (NTRS)

    Trigwell, Steve; Captain, James; Weis, Kyle; Quinn, Jacqueline

    2011-01-01

    Upon returning to the moon, or further a field such as Mars, presents enormous challenges in sustaining life for extended periods of time far beyond the few days the astronauts experienced on the moon during the Apollo missions. A stay on Mars is envisioned to last several months, and it would be cost prohibitive to take all the requirements for such a stay from earth. Therefore, future exploration missions will be required to be self-sufficient and utilize the resources available at the mission site to sustain human occupation. Such an exercise is currently the focus of intense research at NASA under the In-situ Resource Utilization (ISRU) program. As well as oxygen and water necessary for human life, resources for providing building materials for habitats, radiation protection, and landing/launch pads are required. All these materials can be provided by the regolith present on the surface as it contains sufficient minerals and metals oxides to meet the requirements. However, before processing, it would be cost effective if the regolith could be enriched in the mineral(s) of interest. This can be achieved by electrostatic beneficiation in which tribocharged mineral particles are separated out and the feedstock enriched or depleted as required. The results of electrostatic beneficiation of lunar simulants and actual Apollo regolith, in lunar high vacuum are reported in which various degrees of efficient particle separation and mineral enrichment up to a few hundred percent were achieved.

  18. Ultrafast Phase Mapping of Thin-Sections from An Apollo 16 Drive Tube - a New Visualisation of Lunar Regolith

    NASA Technical Reports Server (NTRS)

    Botha, Pieter; Butcher, Alan R.; Horsch, Hana; Rickman, Doug; Wentworth, Susan J.; Schrader, Christian M.; Stoeser, Doug; Benedictus, Aukje; Gottlieb, Paul; McKay, David

    2008-01-01

    Polished thin-sections of samples extracted from Apollo drive tubes provide unique insights into the structure of the Moon's regolith at various landing sites. In particular, they allow the mineralogy and texture of the regolith to be studied as a function of depth. Much has been written about such thin-sections based on optical, SEM and EPMA studies, in terms of their essential petrographic features, but there has been little attempt to quantify these aspects from a spatial perspective. In this study, we report the findings of experimental analysis of two thin-sections (64002, 6019, depth range 5.0 - 8.0 cm & 64001, 6031, depth range 50.0 - 53.1 cm), from a single Apollo 16 drive tube using QEMSCAN . A key feature of the method is phase identification by ultrafast energy dispersive x-ray mapping on a pixel-by-pixel basis. By selecting pixel resolutions ranging from 1 - 5 microns, typically 8,500,000 individual measurement points can be collected on a thin-section. The results we present include false colour digital images of both thin-sections. From these images, information such as phase proportions (major, minor and trace phases), particle textures, packing densities, and particle geometries, has been quantified. Parameters such as porosity and average phase density, which are of geomechanical interest, can also be calculated automatically. This study is part of an on-going investigation into spatial variation of lunar regolith and NASA's ISRU Lunar Simulant Development Project.

  19. Heat Pipe Solar Receiver for Oxygen Production of Lunar Regolith

    NASA Astrophysics Data System (ADS)

    Hartenstine, John R.; Anderson, William G.; Walker, Kara L.; Ellis, Michael C.

    2009-03-01

    A heat pipe solar receiver operating in the 1050° C range is proposed for use in the hydrogen reduction process for the extraction of oxygen from the lunar soil. The heat pipe solar receiver is designed to accept, isothermalize and transfer solar thermal energy to reactors for oxygen production. This increases the available area for heat transfer, and increases throughput and efficiency. The heat pipe uses sodium as the working fluid, and Haynes 230 as the heat pipe envelope material. Initial design requirements have been established for the heat pipe solar receiver design based on information from the NASA In-Situ Resource Utilization (ISRU) program. Multiple heat pipe solar receiver designs were evaluated based on thermal performance, temperature uniformity, and integration with the solar concentrator and the regolith reactor(s). Two designs were selected based on these criteria: an annular heat pipe contained within the regolith reactor and an annular heat pipe with a remote location for the reactor. Additional design concepts have been developed that would use a single concentrator with a single solar receiver to supply and regulate power to multiple reactors. These designs use variable conductance or pressure controlled heat pipes for passive power distribution management between reactors. Following the design study, a demonstration heat pipe solar receiver was fabricated and tested. Test results demonstrated near uniform temperature on the outer surface of the pipe, which will ultimately be in contact with the regolith reactor.

  20. Improved Discrimination of Volcanic Complexes, Tectonic Features, and Regolith Properties in Mare Serenitatis from Earth-Based Radar Mapping

    NASA Technical Reports Server (NTRS)

    Campbell, Bruce A.; Hawke, B. Ray; Morgan, Gareth A.; Carter, Lynn M.; Campbell, Donald B.; Nolan, Michael

    2014-01-01

    Radar images at 70 cm wavelength show 4-5 dB variations in backscatter strength within regions of relatively uniform spectral reflectance properties in central and northern Mare Serenitatis, delineating features suggesting lava flow margins, channels, and superposition relationships. These backscatter differences are much less pronounced at 12.6 cm wavelength, consistent with a large component of the 70 cm echo arising from the rough or blocky transition zone between the mare regolith and the intact bedrock. Such deep probing is possible because the ilmenite content, which modulates microwave losses, of central Mare Serenitatis is generally low (2-3% by weight). Modeling of the radar returns from a buried interface shows that an average regolith thickness of 10m could lead to the observed shifts in 70 cm echo power with a change in TiO2 content from 2% to 3%. This thickness is consistent with estimates of regolith depth (10-15m) based on the smallest diameter for which fresh craters have obvious blocky ejecta. The 70 cm backscatter differences provide a view of mare flow-unit boundaries, channels, and lobes unseen by other remote sensing methods. A localized pyroclastic deposit associated with Rima Calippus is identified based on its low radar echo strength. Radar mapping also improves delineation of units for crater age dating and highlights a 250 km long, east-west trending feature in northern Mare Serenitatis that we suggest is a large graben flooded by late-stage mare flows.

Top