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Sample records for lunar surface due

  1. Photometric Lunar Surface Reconstruction

    Science.gov (United States)

    Nefian, Ara V.; Alexandrov, Oleg; Morattlo, Zachary; Kim, Taemin; Beyer, Ross A.

    2013-01-01

    Accurate photometric reconstruction of the Lunar surface is important in the context of upcoming NASA robotic missions to the Moon and in giving a more accurate understanding of the Lunar soil composition. This paper describes a novel approach for joint estimation of Lunar albedo, camera exposure time, and photometric parameters that utilizes an accurate Lunar-Lambertian reflectance model and previously derived Lunar topography of the area visualized during the Apollo missions. The method introduced here is used in creating the largest Lunar albedo map (16% of the Lunar surface) at the resolution of 10 meters/pixel.

  2. Dielectric properties of lunar surface

    Science.gov (United States)

    Yushkova, O. V.; Kibardina, I. N.

    2017-03-01

    Measurements of the dielectric characteristics of lunar soil samples are analyzed in the context of dielectric theory. It has been shown that the real component of the dielectric permittivity and the loss tangent of rocks greatly depend on the frequency of the interacting electromagnetic field and the soil temperature. It follows from the analysis that one should take into account diurnal variations in the lunar surface temperature when interpreting the radar-sounding results, especially for the gigahertz radio range.

  3. Lunar surface engineering properties experiment definition

    Science.gov (United States)

    Mitchell, J. K.; Goodman, R. E.; Hurlbut, F. C.; Houston, W. N.; Willis, D. R.; Witherspoon, P. A.; Hovland, H. J.

    1971-01-01

    Research on the mechanics of lunar soils and on developing probes to determine the properties of lunar surface materials is summarized. The areas of investigation include the following: soil simulation, soil property determination using an impact penetrometer, soil stabilization using urethane foam or phenolic resin, effects of rolling boulders down lunar slopes, design of borehole jack and its use in determining failure mechanisms and properties of rocks, and development of a permeability probe for measuring fluid flow through porous lunar surface materials.

  4. Methane Lunar Surface Thermal Control Test

    Science.gov (United States)

    Plachta, David W.; Sutherlin, Steven G.; Johnson, Wesley L.; Feller, Jeffrey R.; Jurns, John M.

    2012-01-01

    NASA is considering propulsion system concepts for future missions including human return to the lunar surface. Studies have identified cryogenic methane (LCH4) and oxygen (LO2) as a desirable propellant combination for the lunar surface ascent propulsion system, and they point to a surface stay requirement of 180 days. To meet this requirement, a test article was prepared with state-of-the-art insulation and tested in simulated lunar mission environments at NASA GRC. The primary goals were to validate design and models of the key thermal control technologies to store unvented methane for long durations, with a low-density high-performing Multi-layer Insulation (MLI) system to protect the propellant tanks from the environmental heat of low Earth orbit (LEO), Earth to Moon transit, lunar surface, and with the LCH4 initially densified. The data and accompanying analysis shows this storage design would have fallen well short of the unvented 180 day storage requirement, due to the MLI density being much higher than intended, its substructure collapse, and blanket separation during depressurization. Despite the performance issue, insight into analytical models and MLI construction was gained. Such modeling is important for the effective design of flight vehicle concepts, such as in-space cryogenic depots or in-space cryogenic propulsion stages.

  5. Apollo Missions to the Lunar Surface

    Science.gov (United States)

    Graff, Paige V.

    2018-01-01

    Six Apollo missions to the Moon, from 1969-1972, enabled astronauts to collect and bring lunar rocks and materials from the lunar surface to Earth. Apollo lunar samples are curated by NASA Astromaterials at the NASA Johnson Space Center in Houston, TX. Samples continue to be studied and provide clues about our early Solar System. Learn more and view collected samples at: https://curator.jsc.nasa.gov/lunar.

  6. Lunar surface fission power supplies: Radiation issues

    International Nuclear Information System (INIS)

    Houts, M.G.; Lee, S.K.

    1994-01-01

    A lunar space fission power supply shield that uses a combination of lunar regolith and materials brought from earth may be optimal for early lunar outposts and bases. This type of shield can be designed such that the fission power supply does not have to be moved from its landing configuration, minimizing handling and required equipment on the lunar surface. Mechanisms for removing heat from the lunar regolith are built into the shield, and can be tested on earth. Regolith activation is greatly reduced compared with a shield that uses only regolith, and it is possible to keep the thermal conditions of the fission power supply close to these seen in free space. For a well designed shield, the additional mass required to be brought fro earth should be less than 1000 kg. Detailed radiation transport calculations confirm the feasibility of such a shield

  7. Lunar surface fission power supplies: Radiation issues

    International Nuclear Information System (INIS)

    Houts, M.G.; Lee, S.K.

    1994-01-01

    A lunar space fission power supply shield that uses a combination of lunar regolith and materials brought from earth may be optimal for early lunar outposts and bases. This type of shield can be designed such that the fission power supply does not have to be moved from its landing configuration, minimizing handling and required equipment on the lunar surface. Mechanisms for removing heat from the lunar regolith are built into the shield, and can be tested on earth. Regolith activation is greatly reduced compared with a shield that uses only regolith, and it is possible to keep the thermal conditions of the fission power supply close to those seen in free space. For a well designed shield, the additional mass required to be brought from earth should be less than 1,000 kg. Detailed radiation transport calculations confirm the feasibility of such a shield

  8. Visibility of lunar surface features - Apollo 14 orbital observations and lunar landing.

    Science.gov (United States)

    Ziedman, K.

    1972-01-01

    Description of an in-flight visibility test conducted during the Apollo 14 mission for the purpose of validating and extending the mathematical visibility models used previously in the course of the Apollo program to examine the constraints on descent operations imposed by lunar visibility limitations. Following a background review of the effects on mission planning of the visibility limitations due to downsun lunar surface detail 'washout' and a discussion of the visibility prediction techniques previously used for studying lunar visibility problems, the visibility test rationale and procedures are defined and the test results presented. The results appear to confirm the validity of the visibility prediction techniques employed in lunar visibility problem studies. These results provide also a basis for improving the accuracy of the prediction techniques by appropriate modifications.

  9. Life Sciences Implications of Lunar Surface Operations

    Science.gov (United States)

    Chappell, Steven P.; Norcross, Jason R.; Abercromby, Andrew F.; Gernhardt, Michael L.

    2010-01-01

    The purpose of this report is to document preliminary, predicted, life sciences implications of expected operational concepts for lunar surface extravehicular activity (EVA). Algorithms developed through simulation and testing in lunar analog environments were used to predict crew metabolic rates and ground reaction forces experienced during lunar EVA. Subsequently, the total metabolic energy consumption, the daily bone load stimulus, total oxygen needed, and other variables were calculated and provided to Human Research Program and Exploration Systems Mission Directorate stakeholders. To provide context to the modeling, the report includes an overview of some scenarios that have been considered. Concise descriptions of the analog testing and development of the algorithms are also provided. This document may be updated to remain current with evolving lunar or other planetary surface operations, assumptions and concepts, and to provide additional data and analyses collected during the ongoing analog research program.

  10. Lunar atmosphere. How surface composition and meteoroid impacts mediate sodium and potassium in the lunar exosphere.

    Science.gov (United States)

    Colaprete, A; Sarantos, M; Wooden, D H; Stubbs, T J; Cook, A M; Shirley, M

    2016-01-15

    Despite being trace constituents of the lunar exosphere, sodium and potassium are the most readily observed species due to their bright line emission. Measurements of these species by the Ultraviolet and Visible Spectrometer (UVS) on the Lunar Atmosphere and Dust Environment Explorer (LADEE) have revealed unambiguous temporal and spatial variations indicative of a strong role for meteoroid bombardment and surface composition in determining the composition and local time dependence of the Moon's exosphere. Observations show distinct lunar day (monthly) cycles for both species as well as an annual cycle for sodium. The first continuous measurements for potassium show a more repeatable variation across lunations and an enhancement over KREEP (Potassium Rare Earth Elements and Phosphorus) surface regions, revealing a strong dependence on surface composition. Copyright © 2016, American Association for the Advancement of Science.

  11. Petrologic Characteristics of the Lunar Surface.

    Science.gov (United States)

    Wang, Xianmin; Pedrycz, Witold

    2015-11-27

    Petrologic analysis of the lunar surface is critical for determining lunar formation and evolution. Here, we report the first global petrologic map that includes the five most important lunar lithological units: the Ferroan Anorthositic (FAN) Unit, the Magnesian Suite (MS) Unit, the Alkali Suite (AS) Unit, the KREEP Basalt (KB) Unit and the Mare Basalt (MB) Unit. Based on the petrologic map and focusing on four long-debated and important issues related to lunar formation and evolution, we draw the following conclusions from the new insights into the global distribution of the five petrologic units: (1) there may be no petrogenetic relationship between MS rocks and KB; (2) there may be no petrogenetic link between MS and AS rocks; (3) the exposure of the KREEP component on the lunar surface is likely not a result of MB volcanism but is instead mainly associated with the combined action of plutonic intrusion, KREEP volcanism and celestial collision; (4) the impact size of the South Pole-Aitken basin is constrained, i.e., the basin has been excavated through the whole crust to exhume a vast majority of lower-crustal material and a very limited mantle components to the lunar surface.

  12. Modelling of Lunar Dust and Electrical Field for Future Lunar Surface Measurements

    Science.gov (United States)

    Lin, Yunlong

    Modelling of the lunar dust and electrical field is important to future human and robotic activities on the surface of the moon. Apollo astronauts had witnessed the maintaining of micron- and millimeter sized moon dust up to meters level while walked on the surface of the moon. The characterizations of the moon dust would enhance not only the scientific understanding of the history of the moon but also the future technology development for the surface operations on the moon. It has been proposed that the maintaining and/or settlement of the small-sized dry dust are related to the size and weight of the dust particles, the level of the surface electrical fields on the moon, and the impaction and interaction between lunar regolith and the solar particles. The moon dust distributions and settlements obviously affected the safety of long term operations of future lunar facilities. For the modelling of the lunar dust and the electrical field, we analyzed the imaging of the legs of the moon lander, the cover and the footwear of the space suits, and the envelope of the lunar mobiles, and estimated the size and charges associated with the small moon dust particles, the gravity and charging effects to them along with the lunar surface environment. We also did numerical simulation of the surface electrical fields due to the impaction of the solar winds in several conditions. The results showed that the maintaining of meters height of the micron size of moon dust is well related to the electrical field and the solar angle variations, as expected. These results could be verified and validated through future on site and/or remote sensing measurements and observations of the moon dust and the surface electrical field.

  13. Lunar surface exploration using mobile robots

    Science.gov (United States)

    Nishida, Shin-Ichiro; Wakabayashi, Sachiko

    2012-06-01

    A lunar exploration architecture study is being carried out by space agencies. JAXA is carrying out research and development of a mobile robot (rover) to be deployed on the lunar surface for exploration and outpost construction. The main target areas for outpost construction and lunar exploration are mountainous zones. The moon's surface is covered by regolith. Achieving a steady traversal of such irregular terrain constitutes the major technical problem for rovers. A newly developed lightweight crawler mechanism can effectively traverse such irregular terrain because of its low contact force with the ground. This fact was determined on the basis of the mass and expected payload of the rover. This paper describes a plan for Japanese lunar surface exploration using mobile robots, and presents the results of testing and analysis needed in their development. This paper also gives an overview of the lunar exploration robot to be deployed in the SELENE follow-on mission, and the composition of its mobility, navigation, and control systems.

  14. Lower-Cost, Relocatable Lunar Polar Lander and Lunar Surface Sample Return Probes

    Science.gov (United States)

    Amato, G. Michael; Garvin, James B.; Burt, I. Joseph; Karpati, Gabe

    2011-01-01

    Key science and exploration objectives of lunar robotic precursor missions can be achieved with the Lunar Explorer (LEx) low-cost, robotic surface mission concept described herein. Selected elements of the LEx concept can also be used to create a lunar surface sample return mission that we have called Boomerang

  15. Astronaut Neil Armstrong participates in lunar surface siumlation training

    Science.gov (United States)

    1969-01-01

    Suited Astronaut Neil A. Armstrong, wearing an Extravehicular Mobility Unit, participates in lunar surface simulation training on April 18, 1969, in bldg 9, Manned Spacecraft Center (MSC). Armstrong is the prime crew commander of the Apollo 11 lunar landing mission. Here, he simulates scooping up a lunar surface sample.

  16. Spectroscopic observations of the Moon at the lunar surface

    Science.gov (United States)

    Wu, Yunzhao; Hapke, Bruce

    2018-02-01

    The Moon's reflectance spectrum records many of its important properties. However, prior to Chang'E-3 (CE-3), no spectra had previously been measured on the lunar surface. Here we show the in situ reflectance spectra of the Moon acquired on the lunar surface by the Visible-Near Infrared Spectrometer (VNIS) onboard the CE-3 rover. The VNIS detected thermal radiation from the lunar regolith, though with much shorter wavelength range than typical thermal radiometer. The measured temperatures are higher than expected from theoretical model, indicating low thermal inertia of the lunar soil and the effects of grain facet on soil temperature in submillimeter scale. The in situ spectra also reveal that 1) brightness changes visible from orbit are related to the reduction in maturity due to the removal of the fine and weathered particles by the lander's rocket exhaust, not the smoothing of the surface and 2) the spectra of the uppermost soil detected by remote sensing exhibit substantial differences with that immediately beneath, which has important implications for the remote compositional analysis. The reflectance spectra measured by VNIS not only reveal the thermal, compositional, and space-weathering properties of the Moon but also provide a means for the calibration of optical instruments that view the surface remotely.

  17. Remote compositional mapping of lunar titanium and surface maturity

    Science.gov (United States)

    Johnson, J. R.; Larson, S. M.; Singer, Robert B.

    1991-01-01

    Lunar ilmenite (FeTiO3) is a potential resource capable of providing oxygen for life support and spacecraft propellant for future lunar bases. Estimates of TiO2 content in mature mare soils can be made using an empirical relation between the 400/500 nm reflectance ratio and TiO2 wt percent. A TiO2 abundance map was constructed for the entire near-side lunar maria accurate to + or - 2 wt percent TiO2 using CCD images obtained at the Tumamoc Hill 0.5 m telescope in Tucson, employing bandpass filters centered at 400 and 560 nm. Highest TiO2 regions in the maria are located in western Mare Tranquillitatis. Greater contrast differences between regions on the lunar surface can be obtained using 400/730 nm ratio images. The relation might well be refined to accommodate this possibly more sensitive indicator of TiO2 content. Another potential lunar resource is solar wind-implanted He-3 which may be used as a fuel for fusion reactors. Relative soil maturity, as determined by agglutinate content, can be estimated from 950/560 nm ration images. Immature soils appear darker in this ratio since such soils contain abundant pyroxene grains which cause strong absorption centered near 950 nm due Fe(2+) crystal field transitions. A positive correlation exists between the amount of He-3 and TiO2 content in lunar soils, suggesting that regions high in TiO2 should also be high in He-3. Reflectance spectrophotometry in the region 320 to 870 nm was also obtained for several regions. Below about 340 nm, these spectra show variations in relative reflectance that are caused by as yet unassigned near-UV absorptions due to compositional differences.

  18. Astronaut Neil Armstrong participates in lunar surface simulation training

    Science.gov (United States)

    1969-01-01

    Astronaut Neil A. Armstrong, wearing an Extravehicular Mobility Unit (EMU), participates in lunar surface simulation training on April 18, 1969 in bldg 9, Manned Spacecraft Center. Armstrong is the prime crew commander of the Apollo 11 lunar landing mission. Here, he is standing on Lunar Module mockup foot pad preparing to ascend steps.

  19. Distribution of iron and titanium on the lunar surface from lunar prospector gamma ray spectra

    International Nuclear Information System (INIS)

    Prettyman, T.H.; Feldman, W.C.; Lawrence, David J.; Elphic, R.C.; Gasnault, O.M.; Maurice, S.; Moore, K.R.; Binder, A.B.

    2001-01-01

    Gamma ray pulse height spectra acquired by the Lunar Prospector (LP) Gamma-Ray Spectrometer (GRS) contain information on the abundance of major elements in the lunar surface, including O, Si, Ti, Al, Fe, Mg, Ca, K, and Th. With the exception of Th and K, prompt gamma rays produced by cosmic ray interactions with surface materials are used to determine elemental abundance. Most of these gamma rays are produced by inelastic scattering of fast neutrons and by neutron capture. The production of neutron-induced gamma rays reaches a maximum deep below the surface (e.g. ∼140 g/cm 2 for inelastic scattering and ∼50 g/cm 2 for capture). Consequently, gamma rays sense the bulk composition of lunar materials, in contrast to optical methods (e.g. Clementine Spectral Reflectance (CSR)), which only sample the top few microns. Because most of the gamma rays are produced deep beneath the surface, few escape unscattered and the continuum of scattered gamma rays dominates the spectrum. In addition, due to the resolution of the spectrometer, there are few well-isolated peaks and peak fitting algorithms must be used to deconvolve the spectrum in order to determine the contribution of individual elements.

  20. Lunar rock surfaces as detectors of solar processes

    International Nuclear Information System (INIS)

    Hartung, J.B.; Hunter College, New York, NY)

    1980-01-01

    Lunar rock surfaces exposed at or just below the lunar surface are considered as detectors of the solar wind, solar flares and solar-derived magnetic fields through their interactions with galactic cosmic rays. The degradation of the solar detector capabilities of lunar surface rocks by meteoroid impact erosion, accreta deposition, loose dust, and sputtering, amorphous layer formation and accelerated diffusion due to solar particles and illumination is discussed, and it is noted that the complex interactions of factors affecting the outer micron of exposed surface material has so far prevented the development of a satisfactory model for a particle detector on the submicron scale. Methods for the determination of surface exposure ages based on the accumulation of light solar wind noble gases, Fe and Mg, impact craters, solar flare tracks, and cosmogenic Kr isotopes are examined, and the systematic variations in the ages determined by the various clocks are discussed. It is concluded that a means of obtaining satisfactory quantitative rate or flux data has not yet been established

  1. Scalable Lunar Surface Networks and Adaptive Orbit Access, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Innovative network architecture, protocols, and algorithms are proposed for both lunar surface networks and orbit access networks. Firstly, an overlaying...

  2. A radiation analysis of lunar surface habitats

    International Nuclear Information System (INIS)

    De Angelis, G.; Wilson, J.W.; Tripathi, R.K.; Clowdsley, M.S.; Nealy, J.E.

    2003-01-01

    An analysis is performed on the radiation environment found on the surface of the Moon, and applied to different possible lunar base mission scenarios. An optimization technique has been used to minimize the astronaut radiation exposure and at the same time control the effect of shielding, in terms of mass addition and material choice, as a mission cost driver. The optimization process performs minimization of mass along all phases of a mission scenario, considered in terms of time frame, equipment, location, crew characteristics and performance required, radiation exposure annual and career limit constraints (those proposed in NCRP 132), and implementation of the ALARA principle. In the lunar environment manned habitats are to host future crews involved in the construction and/or in the utilization of moon based infrastructure. Three different kinds of lunar missions are considered in the analysis, Moon Base Construction Phase, during which astronauts are on the surface just to build an outpost for future resident crews, Moon Base Outpost Phase, during which astronaut crews are resident but continuing exploration and installation activities, and Moon Base Routine Phase, with shifting resident crews. In each scenario various kinds of habitats, from very simple shelters to more complex bases, are considered in detail (e.g. shape, thickness, materials, etc) with considerations of various shielding strategies. The results for all scenarios clearly showed that the direct exposure to the space environment like in transfers and EVAs phases gives the most of the dose, with the proposed shielded habitats and shelters giving quite a good protection from radiation. Operational constraints on hardware and scenarios have all been considered by the optimization techniques. Within the limits of this preliminary analysis, the three Moon Base related mission scenarios are perfectly feasible from the astronaut radiation safety point of view with the currently adopted and proposed

  3. Lunar Surface Systems Supportability Technology Development Roadmap

    Science.gov (United States)

    Oeftering, Richard C.; Struk, Peter M.; Green, Jennifer L.; Chau, Savio N.; Curell, Philip C.; Dempsey, Cathy A.; Patterson, Linda P.; Robbins, William; Steele, Michael A.; DAnnunzio, Anthony; hide

    2011-01-01

    The Lunar Surface Systems Supportability Technology Development Roadmap is a guide for developing the technologies needed to enable the supportable, sustainable, and affordable exploration of the Moon and other destinations beyond Earth. Supportability is defined in terms of space maintenance, repair, and related logistics. This report considers the supportability lessons learned from NASA and the Department of Defense. Lunar Outpost supportability needs are summarized, and a supportability technology strategy is established to make the transition from high logistics dependence to logistics independence. This strategy will enable flight crews to act effectively to respond to problems and exploit opportunities in an environment of extreme resource scarcity and isolation. The supportability roadmap defines the general technology selection criteria. Technologies are organized into three categories: diagnostics, test, and verification; maintenance and repair; and scavenge and recycle. Furthermore, "embedded technologies" and "process technologies" are used to designate distinct technology types with different development cycles. The roadmap examines the current technology readiness level and lays out a four-phase incremental development schedule with selection decision gates. The supportability technology roadmap is intended to develop technologies with the widest possible capability and utility while minimizing the impact on crew time and training and remaining within the time and cost constraints of the program.

  4. Automated Hybrid Microwave Heating for Lunar Surface Solidification, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR project addresses the need for a system that will provide automated lunar surface stabilization via hybrid microwave heating. Surface stabilization is...

  5. Scalable Lunar Surface Networks and Adaptive Orbit Access, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Based on our proposed innovations and accomplished work in Phase I, we will focus on developing the new MAC protocol and hybrid routing protocol for lunar surface...

  6. Development of a Modified Vacuum Cleaner for Lunar Surface Systems

    Science.gov (United States)

    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

  7. Lunar Surface Potential Increases during Terrestrial Bow Shock Traversals

    Science.gov (United States)

    Collier, Michael R.; Stubbs, Timothy J.; Hills, H. Kent; Halekas, Jasper; Farrell, William M.; Delory, Greg T.; Espley, Jared; Freeman, John W.; Vondrak, Richard R.; Kasper, Justin

    2009-01-01

    Since the Apollo era the electric potential of the Moon has been a subject of interest and debate. Deployed by three Apollo missions, Apollo 12, Apollo 14 and Apollo 15, the Suprathermal Ion Detector Experiment (SIDE) determined the sunlit lunar surface potential to be about +10 Volts using the energy spectra of lunar ionospheric thermal ions accelerated toward the Moon. We present an analysis of Apollo 14 SIDE "resonance" events that indicate the lunar surface potential increases when the Moon traverses the dawn bow shock. By analyzing Wind spacecraft crossings of the terrestrial bow shock at approximately this location and employing current balancing models of the lunar surface, we suggest causes for the increasing potential. Determining the origin of this phenomenon will improve our ability to predict the lunar surface potential in support of human exploration as well as provide models for the behavior of other airless bodies when they traverse similar features such as interplanetary shocks, both of which are goals of the NASA Lunar Science Institute's Dynamic Response of the Environment At the Moon (DREAM) team.

  8. Study on Alternative Cargo Launch Options from the Lunar Surface

    Energy Technology Data Exchange (ETDEWEB)

    Cheryl A. Blomberg; Zamir A. Zulkefli; Spencer W. Rich; Steven D. Howe

    2013-07-01

    In the future, there will be a need for constant cargo launches from Earth to Mars in order to build, and then sustain, a Martian base. Currently, chemical rockets are used for space launches. These are expensive and heavy due to the amount of necessary propellant. Nuclear thermal rockets (NTRs) are the next step in rocket design. Another alternative is to create a launcher on the lunar surface that uses magnetic levitation to launch cargo to Mars in order to minimize the amount of necessary propellant per mission. This paper investigates using nuclear power for six different cargo launching alternatives, as well as the orbital mechanics involved in launching cargo to a Martian base from the moon. Each alternative is compared to the other alternative launchers, as well as compared to using an NTR instead. This comparison is done on the basis of mass that must be shipped from Earth, the amount of necessary propellant, and the number of equivalent NTR launches. Of the options, a lunar coil launcher had a ship mass that is 12.7% less than the next best option and 17 NTR equivalent launches, making it the best of the presented six options.

  9. Lunar dusty plasma: A result of interaction of the solar wind flux and ultraviolet radiation with the lunar surface

    International Nuclear Information System (INIS)

    Lisin, E A; Tarakanov, V P; Petrov, O F; Popel, S I

    2015-01-01

    One of the main problems of future missions to the Moon is associated with lunar dust. Solar wind flux and ultraviolet radiation interact with the lunar surface. As a result, there is a substantial surface change and a near-surface plasma sheath. Dust particles from the lunar regolith, which turned in this plasma because of any mechanical processes, can levitate above the surface, forming dust clouds. In preparing of the space experiments “Luna-Glob” and “Luna-Resource” particle-in-cell calculations of the near-surface plasma sheath parameters are carried out. Here we present some new results of particle-in-cell simulation of the plasma sheath formed near the surface of the moon as a result of interaction of the solar wind and ultraviolet radiation with the lunar surface. The conditions of charging and stable levitation of dust particles in plasma above the lunar surface are also considered. (paper)

  10. Hydrogen and fluorine in the surfaces of lunar samples

    International Nuclear Information System (INIS)

    Leich, D.A.; Goldberg, R.H.; Burnett, D.S.; Tombrello, T.A.

    1974-04-01

    The resonant nuclear reaction F-19 (p, alpha gamma)O-16 was used to perform depth sensitive analyses for both fluorine and hydrogen in lunar samples. The resonance at 0.83 MeV (center-of-mass) in this reaction was applied to the measurement of the distribution of trapped solar protons in lunar samples to depths of about 1 / 2 micrometer. These results are interpreted in terms of terrestrial H 2 O surface contamination and a redistribution of the implanted solar H which has been influenced by heavy radiation damage in the surface region. Results are also presented for an experiment to test the penetration of H 2 O into laboratory glass samples which have been irradiated with O-16 to simulate the radiation damaged surfaces of lunar glasses. Fluorine determinations were performed in a 1 pm surface layer on lunar samples using the same F-19(alpha gamma)O-16 resonance. The data are discussed from the standpoint of lunar fluorine and Teflon contamination. (U.S.)

  11. Data Analysis Techniques for a Lunar Surface Navigation System Testbed

    Science.gov (United States)

    Chelmins, David; Sands, O. Scott; Swank, Aaron

    2011-01-01

    NASA is interested in finding new methods of surface navigation to allow astronauts to navigate on the lunar surface. In support of the Vision for Space Exploration, the NASA Glenn Research Center developed the Lunar Extra-Vehicular Activity Crewmember Location Determination System and performed testing at the Desert Research and Technology Studies event in 2009. A significant amount of sensor data was recorded during nine tests performed with six test subjects. This paper provides the procedure, formulas, and techniques for data analysis, as well as commentary on applications.

  12. Lunar Surface Electric Potential Changes Associated with Traversals through the Earth's Foreshock

    Science.gov (United States)

    Collier, Michael R.; Hills, H. Kent; Stubbs, Timothy J.; Halekas, Jasper S.; Delory, Gregory T.; Espley, Jared; Farrell, William M.; Freeman, John W.; Vondrak, Richard

    2011-01-01

    We report an analysis of one year of Suprathermal Ion Detector Experiment (SIDE) Total Ion Detector (TID) resonance events observed between January 1972 and January 1973. The study includes only those events during which upstream solar wind conditions were readily available. The analysis shows that these events are associated with lunar traversals through the dawn flank of the terrestrial magnetospheric bow shock. We propose that the events result from an increase in lunar surface electric potential effected by secondary electron emission due to primary electrons in the Earth's foreshock region (although primary ions may play a role as well). This work establishes (1) the lunar surface potential changes as the Moon moves through the terrestrial bow shock, (2) the lunar surface achieves potentials in the upstream foreshock region that differ from those in the downstream magnetosheath region, (3) these differences can be explained by the presence of energetic electron beams in the upstream foreshock region and (4) if this explanation is correct, the location of the Moon with respect to the terrestrial bow shock influences lunar surface potential.

  13. Mossbauer analysis of Luna 16 lunar surface material

    Science.gov (United States)

    Nady, D. L.; Cher, L.; Kulcsar, K.

    1974-01-01

    Samples of Apollo 11 lunar surface material were studied by the Mossbauer effect. Owing to the small number of other resonant isotopes, all measurements were made with Fe-57 nuclei. The principal constituents of the material were as follows: Iron containing silicates (olivine, pyroxene, and so on), ilmenite (FeTiO3), and metallic iron.

  14. Advanced construction management for lunar base construction - Surface operations planner

    Science.gov (United States)

    Kehoe, Robert P.

    1992-01-01

    The study proposes a conceptual solution and lays the framework for developing a new, sophisticated and intelligent tool for a lunar base construction crew to use. This concept integrates expert systems for critical decision making, virtual reality for training, logistics and laydown optimization, automated productivity measurements, and an advanced scheduling tool to form a unique new planning tool. The concept features extensive use of computers and expert systems software to support the actual work, while allowing the crew to control the project from the lunar surface. Consideration is given to a logistics data base, laydown area management, flexible critical progress scheduler, video simulation of assembly tasks, and assembly information and tracking documentation.

  15. Reference reactor module for NASA's lunar surface fission power system

    International Nuclear Information System (INIS)

    Poston, David I.; Kapernick, Richard J.; Dixon, David D.; Werner, James; Qualls, Louis; Radel, Ross

    2009-01-01

    Surface fission power systems on the Moon and Mars may provide the first US application of fission reactor technology in space since 1965. The Affordable Fission Surface Power System (AFSPS) study was completed by NASA/DOE to determine the cost of a modest performance, low-technical risk surface power system. The AFSPS concept is now being further developed within the Fission Surface Power (FSP) Project, which is a near-term technology program to demonstrate system-level TRL-6 by 2013. This paper describes the reference FSP reactor module concept, which is designed to provide a net power of 40 kWe for 8 years on the lunar surface; note, the system has been designed with technologies that are fully compatible with a Martian surface application. The reactor concept uses stainless-steel based. UO 2 -fueled, pumped-NaK fission reactor coupled to free-piston Stirling converters. The reactor shielding approach utilizes both in-situ and launched shielding to keep the dose to astronauts much lower than the natural background radiation on the lunar surface. The ultimate goal of this work is to provide a 'workhorse' power system that NASA can utilize in near-term and future Lunar and Martian mission architectures, with the eventual capability to evolve to very high power, low mass systems, for either surface, deep space, and/or orbital missions.

  16. Surface chemistry of selected lunar regions

    International Nuclear Information System (INIS)

    Bielefeld, M.J.; Reedy, R.C.; Metzger, A.E.; Trombka, J.I.; Arnold, J.R.

    1976-01-01

    A completely new analysis has been carried out on the data from the Apollo 15 and 16 γ ray spectrometer experiments. The components of the continuum background have been estimated. The elements Th, K, Fe and Mg give useful results; results for Ti are significant only for a few high Ti regions. Errors are given, and the results are checked by other methods. Concentrations are reported for about sixty lunar regions; the ground track has been subdivided in various ways. The borders of the maria seem well-defined chemically, while the distribution of KREEP is broad. This wide distribution requires emplacement of KREEP before the era of mare formation. Its high concentration in western mare soils seems to require major vertical mixing

  17. A program of data synthesis from the ALSEP/CPLEE ALSEP/SIDE, and Explorer 35 magnetometer to investigate lunar terminator and nightside particle fluxes and surface interactions. Final technical report

    International Nuclear Information System (INIS)

    Reasoner, D.L.

    1976-01-01

    Lunar nightside electron fluxes were studied with the aid of the ALSEP/CPLEE and other instruments. The flux events were shown to be due to (a) electrons propagating upstream from the earth's bow shock, (b) electrons thermalized and scattered to the lunar surface by disturbances along the boundary of the lunar solarwind cavity, and (c) solar wind electrons scattered to the lunar surface by lunar limb shocks and/or compressional disturbances. These electrons were identified as a cause of the high night surface negative potentials observed in tha ALSEP/SIDE ion data. A study was also made of the shadowing of magnetotail plasma sheet electrons by interactions between the lunar body and the ambient magnetic field and by interactions between charged particles and lunar remnant magnetic fields. These shadowing effects were shown to modify lunar surface and near-lunar potential distributions. (Author)

  18. Distillation Designs for the Lunar Surface

    Science.gov (United States)

    Boul, Peter J.; Lange,Kevin E.; Conger, Bruce; Anderson, Molly

    2010-01-01

    Gravity-based distillation methods may be applied to the purification of wastewater on the lunar base. These solutions to water processing are robust physical separation techniques, which may be more advantageous than many other techniques for their simplicity in design and operation. The two techniques can be used in conjunction with each other to obtain high purity water. The components and feed compositions for modeling waste water streams are presented in conjunction with the Aspen property system for traditional stage distillation. While the individual components for each of the waste streams will vary naturally within certain bounds, an analog model for waste water processing is suggested based on typical concentration ranges for these components. Target purity levels for recycled water are determined for each individual component based on NASA s required maximum contaminant levels for potable water Optimum parameters such as reflux ratio, feed stage location, and processing rates are determined with respect to the power consumption of the process. Multistage distillation is evaluated for components in wastewater to determine the minimum number of stages necessary for each of 65 components in humidity condensate and urine wastewater mixed streams.

  19. Gardening process of lunar surface layer inferred from the galactic cosmic-ray exposure ages of lunar samples

    International Nuclear Information System (INIS)

    Iriyama, Jun; Honda, Masatake.

    1979-01-01

    From the cosmic-ray exposure age data, (time scale 10 7 - 10 8 years), of the lunar surface materials, we discuss the gardening process of the lunar surface layer caused by the meteoroid impact cratering. At steady state, it is calculated that, in the region within 10 - 50 m of the surface, a mixing rate of 10 -4 to 10 -5 mm/yr is necessary to match the exposure ages. Observed exposure ages of the lunar samples could be explained by the gardening effect calculated using a crater formation rate which is slightly modified from the current crater population data. (author)

  20. Scalable Lunar Surface Networks and Adaptive Orbit Access

    Science.gov (United States)

    Wang, Xudong

    2015-01-01

    Teranovi Technologies, Inc., has developed innovative network architecture, protocols, and algorithms for both lunar surface and orbit access networks. A key component of the overall architecture is a medium access control (MAC) protocol that includes a novel mechanism of overlaying time division multiple access (TDMA) and carrier sense multiple access with collision avoidance (CSMA/CA), ensuring scalable throughput and quality of service. The new MAC protocol is compatible with legacy Institute of Electrical and Electronics Engineers (IEEE) 802.11 networks. Advanced features include efficiency power management, adaptive channel width adjustment, and error control capability. A hybrid routing protocol combines the advantages of ad hoc on-demand distance vector (AODV) routing and disruption/delay-tolerant network (DTN) routing. Performance is significantly better than AODV or DTN and will be particularly effective for wireless networks with intermittent links, such as lunar and planetary surface networks and orbit access networks.

  1. Engineering design constraints of the lunar surface environment

    Science.gov (United States)

    Morrison, D. A.

    1992-01-01

    Living and working on the lunar surface will be difficult. Design of habitats, machines, tools, and operational scenarios in order to allow maximum flexibility in human activity will require paying attention to certain constraints imposed by conditions at the surface and the characteristics of lunar material. Primary design drivers for habitat, crew health and safety, and crew equipment are: ionizing radiation, the meteoroid flux, and the thermal environment. Secondary constraints for engineering derive from: the physical and chemical properties of lunar surface materials, rock distributions and regolith thicknesses, topography, electromagnetic properties, and seismicity. Protection from ionizing radiation is essential for crew health and safety. The total dose acquired by a crew member will be the sum of the dose acquired during EVA time (when shielding will be least) plus the dose acquired during time spent in the habitat (when shielding will be maximum). Minimizing the dose acquired in the habitat extends the time allowable for EVA's before a dose limit is reached. Habitat shielding is enabling, and higher precision in predicting secondary fluxes produced in shielding material would be desirable. Means for minimizing dose during a solar flare event while on extended EVA will be essential. Early warning of the onset of flare activity (at least a half-hour is feasible) will dictate the time available to take mitigating steps. Warning capability affects design of rovers (or rover tools) and site layout. Uncertainty in solar flare timing is a design constraint that points to the need for quickly accessible or constructible safe havens.

  2. A Lunar Surface System Supportability Technology Development Roadmap

    Science.gov (United States)

    Oeftering, Richard C.; Struk, Peter M.; Taleghani, barmac K.

    2011-01-01

    This paper discusses the establishment of a Supportability Technology Development Roadmap as a guide for developing capabilities intended to allow NASA s Constellation program to enable a supportable, sustainable and affordable exploration of the Moon and Mars. Presented is a discussion of supportability, in terms of space facility maintenance, repair and related logistics and a comparison of how lunar outpost supportability differs from the International Space Station. Supportability lessons learned from NASA and Department of Defense experience and their impact on a future lunar outpost is discussed. A supportability concept for future missions to the Moon and Mars that involves a transition from a highly logistics dependent to a logistically independent operation is discussed. Lunar outpost supportability capability needs are summarized and a supportability technology development strategy is established. The resulting Lunar Surface Systems Supportability Strategy defines general criteria that will be used to select technologies that will enable future flight crews to act effectively to respond to problems and exploit opportunities in an environment of extreme resource scarcity and isolation. This strategy also introduces the concept of exploiting flight hardware as a supportability resource. The technology roadmap involves development of three mutually supporting technology categories, Diagnostics Test and Verification, Maintenance and Repair, and Scavenging and Recycling. The technology roadmap establishes two distinct technology types, "Embedded" and "Process" technologies, with different implementation and thus different criteria and development approaches. The supportability technology roadmap addresses the technology readiness level, and estimated development schedule for technology groups that includes down-selection decision gates that correlate with the lunar program milestones. The resulting supportability technology roadmap is intended to develop a set

  3. Lunar Phases and Emergency Department Visits for Renal Colic Due to Ureteral Calculus.

    Science.gov (United States)

    Yang, Andy W; Johnson, Justin D; Fronczak, Carolyn M; LaGrange, Chad A

    2016-01-01

    Urolithiasis affects an estimated 5% of the population and the lifetime risk of passing a stone in the urinary tract is estimated to be 8-10%. Urinary calculus formation is highly variable and while certain risk factors such as age, gender, seasonality, anatomic abnormality, and metabolic diseases have been identified, not much is known regarding the association of environmental factors such as lunar phases on renal colic. We conducted a retrospective study to test the hypothesis that full moon phase is an environmental factor associated for increased emergency department (ED) visits for renal colic due to ureteral calculus. We analyzed 559 renal colic diagnoses by the ED at the University of Nebraska Medical Center in a 24-month period and compared them with corresponding lunar phases as well as supermoon events. The lunar phases were defined as full moon ± two days, new moon ± two days, and the days in-between as normal days according to the lunar calendar. Supermoon event dates were obtained from NASA. 90 cases (16.1%) were diagnosed during full moon phase, 89 cases (15.9%) were diagnosed during new moon phase, and 380 cases (68.0%) were diagnosed during normal days. The incidence of renal colic showed no statistically significant association with lunar phases or supermoon events. In this retrospective longitudinal study with adequate power, neither full moon phase nor supermoon event exhibited an association with increased renal colic diagnoses due to ureteral calculus by the ED at the University of Nebraska Medical Center.

  4. Low-frequency Radio Observatory on the Lunar Surface (LROLS)

    Science.gov (United States)

    MacDowall, Robert; Network for Exploration and Space Science (NESS)

    2018-06-01

    A radio observatory on the lunar surface will provide the capability to image solar radio bursts and other sources. Radio burst imaging will improve understanding of radio burst mechanisms, particle acceleration, and space weather. Low-frequency observations (less than ~20 MHz) must be made from space, because lower frequencies are blocked by Earth’s ionosphere. Solar radio observations do not mandate an observatory on the farside of the Moon, although such a location would permit study of less intense solar bursts because the Moon occults the terrestrial radio frequency interference. The components of the lunar radio observatory array are: the antenna system consisting of 10 – 100 antennas distributed over a square kilometer or more; the system to transfer the radio signals from the antennas to the central processing unit; electronics to digitize the signals and possibly to calculate correlations; storage for the data until it is down-linked to Earth. Such transmission requires amplification and a high-gain antenna system or possibly laser comm. For observatories on the lunar farside a satellite or other intermediate transfer system is required to direct the signal to Earth. On the ground, the aperture synthesis analysis is completed to display the radio image as a function of time. Other requirements for lunar surface systems include the power supply, utilizing solar arrays with batteries to maintain the system at adequate thermal levels during the lunar night. An alternative would be a radioisotope thermoelectric generator requiring less mass. The individual antennas might be designed with their own solar arrays and electronics to transmit data to the central processing unit, but surviving lunar night would be a challenge. Harnesses for power and data transfer from the central processing unit to the antennas are an alternative, but a harness-based system complicates deployment. The concept of placing the antennas and harnesses on rolls of polyimide and

  5. Interplanetary and lunar surface SP-100 nuclear power applications

    International Nuclear Information System (INIS)

    Josloff, A.T.; Shepard, N.F.; Smith, M.; Stephen, J.D.

    1992-01-01

    This paper describes how the SP-100 Space Reactor Power System (SRPS) can be tailored to meet the specific requirements for a lunar surface power system to meet the needs of the consolidation and utilization phases outlined in the 90-day NASA SEI study report. This same basic power system can also be configured to obtain the low specific masses needed to enable robotic interplanetary science missions employing Nuclear Electric Propulsion (NEP). In both cases it is shown that the SP-100 SRPS can meet the specific requirements. For interplanetary NEP missions, performance upgrades currently being developed in the area of light weight radiators and improved thermoelectric material are assumed to be technology ready in the year 2000 time frame. For lunar applications, some system rearrangement and enclosure of critical components are necessary modifications to the present baseline design

  6. Multi-Beam Surface Lidar for Lunar and Planetary Mapping

    Science.gov (United States)

    Bufton, Jack L.; Garvin, James B.

    1998-01-01

    Surface lidar techniques are now being demonstrated in low Earth orbit with a single beam of pulsed laser radiation at 1064 nm that profiles the vertical structure of Earth surface landforms along the nadir track of a spacecraft. In addition, a profiling laser altimeter, called MOLA, is operating in elliptical Martian orbit and returning surface topography data. These instruments form the basis for suggesting an improved lidar instrument that employs multiple beams for extension of sensor capabilities toward the goal of true, 3-dimensional mapping of the Moon or other similar planetary surfaces. In general the lidar waveform acquired with digitization of a laser echo can be used for laser distance measurement (i.e. range-to-the-surface) by time-of-flight measurement and for surface slope and shape measurements by examining the detailed lidar waveform. This is particularly effective when the intended target is the lunar surface or another planetary body free of any atmosphere. The width of the distorted return pulse is a first order measure of the surface incidence angle, a combination of surface slope and laser beam pointing. Assuming an independent and absolute (with respect to inertial space) measurement of laser beam pointing on the spacecraft, it is possible to derive a surface slope with-respect-to the mean planetary surface or its equipotential gravity surface. Higher-order laser pulse distortions can be interpreted in terms of the vertical relief of the surface or reflectivity variations within the area of the laser beam footprint on the surface.

  7. Evaluation of Surface Modification as a Lunar Dust Mitigation Strategy for Thermal Control Surfaces

    Science.gov (United States)

    Gaier, James R.; Waters, Deborah L.; Misconin, Robert M.; Banks, Bruce A.; Crowder, Mark

    2011-01-01

    Three surface treatments were evaluated for their ability to lower the adhesion between lunar simulant dust and AZ93, AlFEP, and AgFEP thermal control surfaces under simulated lunar conditions. Samples were dusted in situ and exposed to a standardized puff of nitrogen gas. Thermal performance before dusting, after dusting, and after part of the dust was removed by the puff of gas, were compared to perform the assessment. None of the surface treatments was found to significantly affect the adhesion of lunar simulants to AZ93 thermal control paint. Oxygen ion beam texturing also did not lower the adhesion of lunar simulant dust to AlFEP or AgFEP. But a workfunction matching coating and a proprietary Ball Aerospace surface treatment were both found to significantly lower the adhesion of lunar simulants to AlFEP and AgFEP. Based on these results, it is recommended that all these two techniques be further explored as dust mitigation coatings for AlFEP and AgFEP thermal control surfaces.

  8. A Survey of Ballistic Transfers to the Lunar Surface

    Science.gov (United States)

    Anderson, Rodney L.; Parker, Jeffrey S.

    2011-01-01

    In this study techniques are developed which allow an analysis of a range of different types of transfer trajectories from the Earth to the lunar surface. Trajectories ranging from those obtained using the invariant manifolds of unstable orbits to those derived from collision orbits are analyzed. These techniques allow the computation of trajectories encompassing low-energy trajectories as well as more direct transfers. The range of possible trajectory options is summarized, and a broad range of trajectories that exist as a result of the Sun's influence are computed and analyzed. The results are then classified by type, and trades between different measures of cost are discussed.

  9. Lunar Phases and Emergency Department Visits for Renal Colic Due to Ureteral Calculus.

    Directory of Open Access Journals (Sweden)

    Andy W Yang

    Full Text Available Urolithiasis affects an estimated 5% of the population and the lifetime risk of passing a stone in the urinary tract is estimated to be 8-10%. Urinary calculus formation is highly variable and while certain risk factors such as age, gender, seasonality, anatomic abnormality, and metabolic diseases have been identified, not much is known regarding the association of environmental factors such as lunar phases on renal colic. We conducted a retrospective study to test the hypothesis that full moon phase is an environmental factor associated for increased emergency department (ED visits for renal colic due to ureteral calculus.We analyzed 559 renal colic diagnoses by the ED at the University of Nebraska Medical Center in a 24-month period and compared them with corresponding lunar phases as well as supermoon events. The lunar phases were defined as full moon ± two days, new moon ± two days, and the days in-between as normal days according to the lunar calendar. Supermoon event dates were obtained from NASA.90 cases (16.1% were diagnosed during full moon phase, 89 cases (15.9% were diagnosed during new moon phase, and 380 cases (68.0% were diagnosed during normal days. The incidence of renal colic showed no statistically significant association with lunar phases or supermoon events.In this retrospective longitudinal study with adequate power, neither full moon phase nor supermoon event exhibited an association with increased renal colic diagnoses due to ureteral calculus by the ED at the University of Nebraska Medical Center.

  10. Impact of Water Recovery from Wastes on the Lunar Surface Mission Water Balance

    Science.gov (United States)

    Fisher, John W.; Hogan, John Andrew; Wignarajah, Kanapathipi; Pace, Gregory S.

    2010-01-01

    Future extended lunar surface missions will require extensive recovery of resources to reduce mission costs and enable self-sufficiency. Water is of particular importance due to its potential use for human consumption and hygiene, general cleaning, clothes washing, radiation shielding, cooling for extravehicular activity suits, and oxygen and hydrogen production. Various water sources are inherently present or are generated in lunar surface missions, and subject to recovery. They include: initial water stores, water contained in food, human and other solid wastes, wastewaters and associated brines, ISRU water, and scavenging from residual propellant in landers. This paper presents the results of an analysis of the contribution of water recovery from life support wastes on the overall water balance for lunar surface missions. Water in human wastes, metabolic activity and survival needs are well characterized and dependable figures are available. A detailed life support waste model was developed that summarizes the composition of life support wastes and their water content. Waste processing technologies were reviewed for their potential to recover that water. The recoverable water in waste is a significant contribution to the overall water balance. The value of this contribution is discussed in the context of the other major sources and loses of water. Combined with other analyses these results provide guidance for research and technology development and down-selection.

  11. Benefits of Using a Mars Forward Strategy for Lunar Surface Systems

    Science.gov (United States)

    Mulqueen, Jack; Griffin, Brand; Smitherman, David; Maples, Dauphne

    2009-01-01

    This paper identifies potential risk reduction, cost savings and programmatic procurement benefits of a Mars Forward Lunar Surface System architecture that provides commonality or evolutionary development paths for lunar surface system elements applicable to Mars surface systems. The objective of this paper is to identify the potential benefits for incorporating a Mars Forward development strategy into the planned Project Constellation Lunar Surface System Architecture. The benefits include cost savings, technology readiness, and design validation of systems that would be applicable to lunar and Mars surface systems. The paper presents a survey of previous lunar and Mars surface systems design concepts and provides an assessment of previous conclusions concerning those systems in light of the current Project Constellation Exploration Architectures. The operational requirements for current Project Constellation lunar and Mars surface system elements are compared and evaluated to identify the potential risk reduction strategies that build on lunar surface systems to reduce the technical and programmatic risks for Mars exploration. Risk reduction for rapidly evolving technologies is achieved through systematic evolution of technologies and components based on Moore's Law superimposed on the typical NASA systems engineering project development "V-cycle" described in NASA NPR 7120.5. Risk reduction for established or slowly evolving technologies is achieved through a process called the Mars-Ready Platform strategy in which incremental improvements lead from the initial lunar surface system components to Mars-Ready technologies. The potential programmatic benefits of the Mars Forward strategy are provided in terms of the transition from the lunar exploration campaign to the Mars exploration campaign. By utilizing a sequential combined procurement strategy for lunar and Mars exploration surface systems, the overall budget wedges for exploration systems are reduced and the

  12. Landing Site Selection and Surface Traverse Planning using the Lunar Mapping & Modeling Portal

    Science.gov (United States)

    Law, E.; Chang, G.; Bui, B.; Sadaqathullah, S.; Kim, R.; Dodge, K.; Malhotra, S.

    2013-12-01

    Introduction: The Lunar Mapping and Modeling Portal (LMMP), is a web-based Portal and a suite of interactive visualization and analysis tools for users to access mapped lunar data products (including image mosaics, digital elevation models, etc.) from past and current lunar missions (e.g., Lunar Reconnaissance Orbiter, Apollo, etc.), and to perform in-depth analyses to support lunar surface mission planning and system design for future lunar exploration and science missions. It has been widely used by many scientists mission planners, as well as educators and public outreach (e.g., Google Lunar XPRICE teams, RESOLVE project, museums etc.) This year, LMMP was used by the Lunar and Planetary Institute (LPI)'s Lunar Exploration internship program to perform lighting analysis and local hazard assessments, such as, slope, surface roughness and crater/boulder distribution to research landing sites and surface pathfinding and traversal. Our talk will include an overview of LMMP, a demonstration of the tools as well as a summary of the LPI Lunar Exploration summer interns' experience in using those tools.

  13. Autonomous Utility Connector for Lunar Surface Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Lunar dust has been identified as a significant and present challenge in future exploration missions. The interlocking, angular nature of Lunar dust and its broad...

  14. Lightweight Bulldozer Attachment for Construction and Excavation on the Lunar Surface

    Science.gov (United States)

    Mueller, Robert; Wilkinson, R. Allen; Gallo, Christopher A.; Nick, Andrew J.; Schuler, Jason M.; King, Robert H.

    2009-01-01

    A lightweight bulldozer blade prototype has been designed and built to be used as an excavation implement in conjunction with the NASA Chariot lunar mobility platform prototype. The combined system was then used in a variety of field tests in order to characterize structural loads, excavation performance and learn about the operational behavior of lunar excavation in geotechnical lunar simulants. The purpose of this effort was to evaluate the feasibility of lunar excavation for site preparation at a planned NASA lunar outpost. Once the feasibility has been determined then the technology will become available as a candidate element in the NASA Lunar Surface Systems Architecture. In addition to NASA experimental testing of the LANCE blade, NASA engineers completed analytical work on the expected draft forces using classical soil mechanics methods. The Colorado School of Mines (CSM) team utilized finite element analysis (FEA) to study the interaction between the cutting edge of the LANCE blade and the surface of soil. FEA was also used to examine various load cases and their effect on the lightweight structure of the LANCE blade. Overall it has been determined that a lunar bulldozer blade is a viable technology for lunar outpost site preparation, but further work is required to characterize the behavior in 1/6th G and actual lunar regolith in a vacuum lunar environment.

  15. The Design of Two Nano-Rovers for Lunar Surface Exploration in the Context of the Google Lunar X Prize

    Science.gov (United States)

    Gill, E.; Honfi Camilo, L.; Kuystermans, P.; Maas, A. S. B. B.; Buutfeld, B. A. M.; van der Pols, R. H.

    2008-09-01

    This paper summarizes a study performed by ten students at the Delft University of Technology on a lunar exploration vehicle suited for competing in the Google Lunar X Prize1. The design philosophy aimed at a quick and simple design process, to comply with the mission constraints. This is achieved by using conventional technology and performing the mission with two identical rovers, increasing reliability and simplicity of systems. Both rovers are however capable of operating independently. The required subsystems have been designed for survival and operation on the lunar surface for an estimated mission lifetime of five days. This preliminary study shows that it is possible for two nano-rovers to perform the basic exploration tasks. The mission has been devised such that after launch the rovers endure a 160 hour voyage to the Moon after which they will land on Sinus Medii with a dedicated lunar transfer/lander vehicle. The mission outline itself has the two nano-rovers travelling in the same direction, moving simultaneously. This mission characteristic allows a quick take-over of the required tasks by the second rover in case of one rover breakdown. The main structure of the rovers will consist of Aluminium 2219 T851, due to its good thermal properties and high hardness. Because of the small dimensions of the rovers, the vehicles will use rigid caterpillar tracks as locomotion system. The track systems are sealed from lunar dust using closed track to prevent interference with the mechanisms. This also prevents any damage to the electronics inside the tracks. For the movement speed a velocity of 0.055 m/s has been determined. This is about 90% of the maximum rover velocity, allowing direct control from Earth. The rovers are operated by a direct control loop, involving the mission control center. In order to direct the rovers safely, a continuous video link with the Earth is necessary to assess its immediate surroundings. Two forward pointing navigational cameras

  16. Evidence for Surface Water Ice in the Lunar Polar Regions Using Reflectance Measurements from the Lunar Orbiter Laser Altimeter and Temperature Measurements from the Diviner Lunar Radiometer Experiment

    Science.gov (United States)

    Fisher, Elizabeth A.; Lucey, Paul G.; Lemelin, Myriam; Greenhagen, Benjamin T.; Siegler, Matthew A.; Mazarico, Erwan; Aharonson, Oded; Williams, Jean-Pierre; Hayne, Paul O.; Neumann, Gregory A.; hide

    2017-01-01

    We find that the reflectance of the lunar surface within 5 deg of latitude of theSouth Pole increases rapidly with decreasing temperature, near approximately 110K, behavior consistent with the presence of surface water ice. The North polar region does not show this behavior, nor do South polar surfaces at latitudes more than 5 deg from the pole. This South pole reflectance anomaly persists when analysis is limited to surfaces with slopes less than 10 deg to eliminate false detection due to the brightening effect of mass wasting, and also when the very bright south polar crater Shackleton is excluded from the analysis. We also find that south polar regions of permanent shadow that have been reported to be generally brighter at 1064 nm do not show anomalous reflectance when their annual maximum surface temperatures are too high to preserve water ice. This distinction is not observed at the North Pole. The reflectance excursion on surfaces with maximum temperatures below 110K is superimposed on a general trend of increasing reflectance with decreasing maximum temperature that is present throughout the polar regions in the north and south; we attribute this trend to a temperature or illumination-dependent space weathering effect (e.g. Hemingway et al. 2015). We also find a sudden increase in reflectance with decreasing temperature superimposed on the general trend at 200K and possibly at 300K. This may indicate the presence of other volatiles such as sulfur or organics. We identified and mapped surfaces with reflectances so high as to be unlikely to be part of an ice-free population. In this south we find a similar distribution found by Hayne et al. 2015 based on UV properties. In the north a cluster of pixels near that pole may represent a limited frost exposure.

  17. Evidence for surface water ice in the lunar polar regions using reflectance measurements from the Lunar Orbiter Laser Altimeter and temperature measurements from the Diviner Lunar Radiometer Experiment

    Science.gov (United States)

    Fisher, Elizabeth A.; Lucey, Paul G.; Lemelin, Myriam; Greenhagen, Benjamin T.; Siegler, Matthew A.; Mazarico, Erwan; Aharonson, Oded; Williams, Jean-Pierre; Hayne, Paul O.; Neumann, Gregory A.; Paige, David A.; Smith, David E.; Zuber, Maria T.

    2017-08-01

    We find that the reflectance of the lunar surface within 5° of latitude of the South Pole increases rapidly with decreasing temperature, near ∼110 K, behavior consistent with the presence of surface water ice. The North polar region does not show this behavior, nor do South polar surfaces at latitudes more than 5° from the pole. This South pole reflectance anomaly persists when analysis is limited to surfaces with slopes less than 10° to eliminate false detection due to the brightening effect of mass wasting, and also when the very bright south polar crater Shackleton is excluded from the analysis. We also find that south polar regions of permanent shadow that have been reported to be generally brighter at 1064 nm do not show anomalous reflectance when their annual maximum surface temperatures are too high to preserve water ice. This distinction is not observed at the North Pole. The reflectance excursion on surfaces with maximum temperatures below 110 K is superimposed on a general trend of increasing reflectance with decreasing maximum temperature that is present throughout the polar regions in the north and south; we attribute this trend to a temperature or illumination-dependent space weathering effect (e.g. Hemingway et al., 2015). We also find a sudden increase in reflectance with decreasing temperature superimposed on the general trend at 200 K and possibly at 300 K. This may indicate the presence of other volatiles such as sulfur or organics. We identified and mapped surfaces with reflectances so high as to be unlikely to be part of an ice-free population. In this south we find a similar distribution found by Hayne et al. (2015) based on UV properties. In the north a cluster of pixels near that pole may represent a limited frost exposure.

  18. Specific heats of lunar surface materials from 90 to 350 degrees Kelvin

    Science.gov (United States)

    Robie, R.A.; Hemingway, B.S.; Wilson, W.H.

    1970-01-01

    The specific heats of lunar samples 10057 and 10084 returned by the Apollo 11 mission have been measured between 90 and 350 degrees Kelvin by use of an adiabatic calorimeter. The samples are representative of type A vesicular basalt-like rocks and of finely divided lunar soil. The specific heat of these materials changes smoothly from about 0.06 calorie per gram per degree at 90 degrees Kelvin to about 0.2 calorie per gram per degree at 350 degrees Kelvin. The thermal parameter ??=(k??C)-1/2 for the lunar surface will accordingly vary by a factor of about 2 between lunar noon and midnight.

  19. Electron content near the lunar surface using dual-frequency VLBI tracking data in a single lunar orbiter mission

    International Nuclear Information System (INIS)

    Wang, Zhen; Wang, Na; Ping, Jin-Song

    2015-01-01

    In VLBI observations of Vstar, a subsatellite of the Japanese lunar mission SELENE, there were opportunities for lunar grazing occultation when Vstar was very close to the limb of the Moon. This kind of chance made it possible to probe the thin plasma layer above the Moon's surface as a meaningful by-product of VLBI, by using the radio occultation method with coherent radio waves from the S/X bands. The dual-frequency measurements were carried out at Earth-based VLBI stations. In the line-of-sight direction between the satellite and the ground-based tracking station where VLBI measurements were made, the effects of the terrestrial ionosphere, interplanetary plasma and the thin lunar ionosphere mixed together in the combined observables of dual-frequency Doppler shift and phase shift. To separate the variation of the ionospheric total electron content (TEC) near the surface of the Moon from the mixed signal, the influences of the terrestrial ionosphere and interplanetary plasma have been removed by using an extrapolation method based on a short-term trend. The lunar TEC is estimated from the dual-frequency observation for Vstar from UT 22:18 to UT 22:20 on 2008 June 28 at several tracking stations. The TEC results obtained from VLBI sites are identical, however, they are not as remarkable as the result obtained at the Usuda deep space tracking station. (paper)

  20. Development of a Lunar Surface Architecture Using the Deep Space Gateway

    Science.gov (United States)

    Corrigan, A. M.; Kitmanyen, V. A.; Prakash, A.

    2018-02-01

    Prior to sending crews to Mars, the ability to perform activities intended for martian missions must first be thoroughly tested and successfully demonstrated in a similar environment. This paper outlines a lunar surface architecture to meet this goal.

  1. Alteration of Lunar Rock Surfaces through Interaction with the Space Environment

    Science.gov (United States)

    Frushour, A. M.; Noble, S. K; Christoffersen, R.; Keller, L P.

    2014-01-01

    Space weathering occurs on all ex-posed surfaces of lunar rocks, as well as on the surfaces of smaller grains in the lunar regolith. Space weather-ing alters these exposed surfaces primarily through the action of solar wind ions and micrometeorite impact processes. On lunar rocks specifically, the alteration products produced by space weathering form surface coatings known as patina. Patinas can have spectral reflectance properties different than the underlying rock. An understanding of patina composition and thickness is therefore important for interpreting re-motely sensed data from airless solar system bodies. The purpose of this study is to try to understand the physical and chemical properties of patina by expanding the number of patinas known and characterized in the lunar rock sample collection.

  2. Autonomous Utility Connector for Lunar Surface Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Lunar dust has been identified as a significant and present challenge in future exploration missions. Significant development is called for in the area of devices...

  3. Deep Space Gateway Support of Lunar Surface Ops and Tele-Operational Transfer of Surface Assets to the Next Landing Site

    Science.gov (United States)

    Kring, D. A.

    2018-02-01

    The Deep Space Gateway can support astronauts on the lunar surface, providing them a departure and returning rendezvous point, a communication relay from the lunar farside to Earth, and a transfer point to Orion for return to Earth.

  4. PHOTOMETRIC STEREO SHAPE-AND-ALBEDO-FROM-SHADING FOR PIXEL-LEVEL RESOLUTION LUNAR SURFACE RECONSTRUCTION

    Directory of Open Access Journals (Sweden)

    W. C. Liu

    2017-07-01

    Full Text Available Shape and Albedo from Shading (SAfS techniques recover pixel-wise surface details based on the relationship between terrain slopes, illumination and imaging geometry, and the energy response (i.e., image intensity captured by the sensing system. Multiple images with different illumination geometries (i.e., photometric stereo can provide better SAfS surface reconstruction due to the increase in observations. Photometric stereo SAfS is suitable for detailed surface reconstruction of the Moon and other extra-terrestrial bodies due to the availability of photometric stereo and the less complex surface reflecting properties (i.e., albedo of the target bodies as compared to the Earth. Considering only one photometric stereo pair (i.e., two images, pixel-variant albedo is still a major obstacle to satisfactory reconstruction and it needs to be regulated by the SAfS algorithm. The illumination directional difference between the two images also becomes an important factor affecting the reconstruction quality. This paper presents a photometric stereo SAfS algorithm for pixel-level resolution lunar surface reconstruction. The algorithm includes a hierarchical optimization architecture for handling pixel-variant albedo and improving performance. With the use of Lunar Reconnaissance Orbiter Camera - Narrow Angle Camera (LROC NAC photometric stereo images, the reconstructed topography (i.e., the DEM is compared with the DEM produced independently by photogrammetric methods. This paper also addresses the effect of illumination directional difference in between one photometric stereo pair on the reconstruction quality of the proposed algorithm by both mathematical and experimental analysis. In this case, LROC NAC images under multiple illumination directions are utilized by the proposed algorithm for experimental comparison. The mathematical derivation suggests an illumination azimuthal difference of 90 degrees between two images is recommended to achieve

  5. Ground Simulations of Near-Surface Plasma Field and Charging at the Lunar Terminator

    Science.gov (United States)

    Polansky, J.; Ding, N.; Wang, J.; Craven, P.; Schneider, T.; Vaughn, J.

    2012-12-01

    Charging in the lunar terminator region is the most complex and is still not well understood. In this region, the surface potential is sensitively influenced by both solar illumination and plasma flow. The combined effects from localized shadow generated by low sun elevation angles and localized wake generated by plasma flow over the rugged terrain can generate strongly differentially charged surfaces. Few models currently exist that can accurately resolve the combined effects of plasma flow and solar illumination over realistic lunar terminator topographies. This paper presents an experimental investigation of lunar surface charging at the terminator region in simulated plasma environments in a vacuum chamber. The solar wind plasma flow is simulated using an electron bombardment gridded Argon ion source. An electrostatic Langmuir probe, nude Faraday probes, a floating emissive probe, and retarding potential analyzer are used to quantify the plasma flow field. Surface potentials of both conducting and dielectric materials immersed in the plasma flow are measured with a Trek surface potential probe. The conducting material surface potential will simultaneously be measured with a high impedance voltmeter to calibrate the Trek probe. Measurement results will be presented for flat surfaces and objects-on-surface for various angles of attack of the plasma flow. The implications on the generation of localized plasma wake and surface charging at the lunar terminator will be discussed. (This research is supported by the NASA Lunar Advanced Science and Exploration Research program.)

  6. A thermal control system for long-term survival of scientific instruments on lunar surface.

    Science.gov (United States)

    Ogawa, K; Iijima, Y; Sakatani, N; Otake, H; Tanaka, S

    2014-03-01

    A thermal control system is being developed for scientific instruments placed on the lunar surface. This thermal control system, Lunar Mission Survival Module (MSM), was designed for scientific instruments that are planned to be operated for over a year in the future Japanese lunar landing mission SELENE-2. For the long-term operations, the lunar surface is a severe environment because the soil (regolith) temperature varies widely from nighttime -200 degC to daytime 100 degC approximately in which space electronics can hardly survive. The MSM has a tent of multi-layered insulators and performs a "regolith mound". Temperature of internal devices is less variable just like in the lunar underground layers. The insulators retain heat in the regolith soil in the daylight, and it can keep the device warm in the night. We conducted the concept design of the lunar survival module, and estimated its potential by a thermal mathematical model on the assumption of using a lunar seismometer designed for SELENE-2. Thermal vacuum tests were also conducted by using a thermal evaluation model in order to estimate the validity of some thermal parameters assumed in the computed thermal model. The numerical and experimental results indicated a sufficient survivability potential of the concept of our thermal control system.

  7. A thermal control system for long-term survival of scientific instruments on lunar surface

    International Nuclear Information System (INIS)

    Ogawa, K.; Iijima, Y.; Tanaka, S.; Sakatani, N.; Otake, H.

    2014-01-01

    A thermal control system is being developed for scientific instruments placed on the lunar surface. This thermal control system, Lunar Mission Survival Module (MSM), was designed for scientific instruments that are planned to be operated for over a year in the future Japanese lunar landing mission SELENE-2. For the long-term operations, the lunar surface is a severe environment because the soil (regolith) temperature varies widely from nighttime −200 degC to daytime 100 degC approximately in which space electronics can hardly survive. The MSM has a tent of multi-layered insulators and performs a “regolith mound”. Temperature of internal devices is less variable just like in the lunar underground layers. The insulators retain heat in the regolith soil in the daylight, and it can keep the device warm in the night. We conducted the concept design of the lunar survival module, and estimated its potential by a thermal mathematical model on the assumption of using a lunar seismometer designed for SELENE-2. Thermal vacuum tests were also conducted by using a thermal evaluation model in order to estimate the validity of some thermal parameters assumed in the computed thermal model. The numerical and experimental results indicated a sufficient survivability potential of the concept of our thermal control system

  8. A thermal control system for long-term survival of scientific instruments on lunar surface

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, K., E-mail: ogawa@astrobio.k.u-tokyo.ac.jp [Department of Complexity Science and Engineering, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba (Japan); Iijima, Y.; Tanaka, S. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo, Sagamihara, Kanagawa (Japan); Sakatani, N. [The Graduate University for Advanced Studies, Shonan Village, Hayama, Kanagawa (Japan); Otake, H. [JAXA Space Exploration Center, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo, Sagamihara, Kanagawa (Japan)

    2014-03-15

    A thermal control system is being developed for scientific instruments placed on the lunar surface. This thermal control system, Lunar Mission Survival Module (MSM), was designed for scientific instruments that are planned to be operated for over a year in the future Japanese lunar landing mission SELENE-2. For the long-term operations, the lunar surface is a severe environment because the soil (regolith) temperature varies widely from nighttime −200 degC to daytime 100 degC approximately in which space electronics can hardly survive. The MSM has a tent of multi-layered insulators and performs a “regolith mound”. Temperature of internal devices is less variable just like in the lunar underground layers. The insulators retain heat in the regolith soil in the daylight, and it can keep the device warm in the night. We conducted the concept design of the lunar survival module, and estimated its potential by a thermal mathematical model on the assumption of using a lunar seismometer designed for SELENE-2. Thermal vacuum tests were also conducted by using a thermal evaluation model in order to estimate the validity of some thermal parameters assumed in the computed thermal model. The numerical and experimental results indicated a sufficient survivability potential of the concept of our thermal control system.

  9. Battery and Fuel Cell Development Goals for the Lunar Surface and Lander

    Science.gov (United States)

    Mercer, Carolyn R.

    2008-01-01

    NASA is planning a return to the moon and requires advances in energy storage technology for its planned lunar lander and lunar outpost. This presentation describes NASA s overall mission goals and technical goals for batteries and fuel cells to support the mission. Goals are given for secondary batteries for the lander s ascent stage and suits for extravehicular activity on the lunar surface, and for fuel cells for the lander s descent stage and regenerative fuel cells for outpost power. An overall approach to meeting these goals is also presented.

  10. Application of automation and robotics to lunar surface human exploration operations

    Science.gov (United States)

    Woodcock, Gordon R.; Sherwood, Brent; Buddington, Patricia A.; Bares, Leona C.; Folsom, Rolfe; Mah, Robert; Lousma, Jack

    1990-01-01

    Major results of a study applying automation and robotics to lunar surface base buildup and operations concepts are reported. The study developed a reference base scenario with specific goals, equipment concepts, robot concepts, activity schedules and buildup manifests. It examined crew roles, contingency cases and system reliability, and proposed a set of technologies appropriate and necessary for effective lunar operations. This paper refers readers to four companion papers for quantitative details where appropriate.

  11. Yet Another Lunar Surface Geologic Exploration Architecture Concept (What, Again?): A Senior Field Geologist's Integrated View

    Science.gov (United States)

    Eppler, D. B.

    2015-01-01

    Lunar surface geological exploration should be founded on a number of key elements that are seemingly disparate, but which can form an integrated operational concept when properly conceived and deployed. If lunar surface geological exploration is to be useful, this integration of key elements needs to be undertaken throughout the development of both mission hardware, training and operational concepts. These elements include the concept of mission class, crew makeup and training, surface mobility assets that are matched with mission class, and field tools and IT assets that make data collection, sharing and archiving transparent to the surface crew.

  12. Determination of lunar surface ages from crater frequency–size ...

    Indian Academy of Sciences (India)

    and the images from Apollo missions have been calibrated from the lunar soil samples from Apollo and Luna landing sites (Head 1976; Neukum et al. 1975). ... Table 1 shows the ages as derived for the craters with errors. Mare Humorum is believed to be made up of six ring structures of 210, 340, 425, 570 and 1195km.

  13. PDS Lunar Data Node Restoration of Apollo In-Situ Surface Data

    Science.gov (United States)

    Williams, David R.; Hills, H. Kent; Guinness, Edward A.; Lowman, Paul D.; Taylor, Patrick T.

    2010-01-01

    The Apollo missions between 1969 and 1972 deployed scientific instruments on the Moon's surface which made in-situ measurements of the lunar environment. Apollo II had the short-term Early Apollo Surface Experiments Package (EASEP) and Apollos 12, 14, 15, 16, and 17 each set up an Apollo Lunar Surface Experiments Package (ALSEP). Each ALSEP package contained a different suite of instruments which took measurements and radioed the results back to Earth over periods from 5 to 7 years until they were turned off on 30 September 1977. To this day the ALSEP data remain the only long-term in-situ information on the Moon's surface environment. The Lunar Data Node (LDN) has been formed under the auspices of the Planetary Data System (PDS) Geosciences Node to put relevant, scientifically important Apollo data into accessible digital form for use by researchers and mission planners. We will report on progress made since last year and plans for future data restorations.

  14. Effect of Space Radiation Processing on Lunar Soil Surface Chemistry: X-Ray Photoelectron Spectroscopy Studies

    Science.gov (United States)

    Dukes, C.; Loeffler, M.J.; Baragiola, R.; Christoffersen, R.; Keller, J.

    2009-01-01

    Current understanding of the chemistry and microstructure of the surfaces of lunar soil grains is dominated by a reference frame derived mainly from electron microscopy observations [e.g. 1,2]. These studies have shown that the outermost 10-100 nm of grain surfaces in mature lunar soil finest fractions have been modified by the combined effects of solar wind exposure, surface deposition of vapors and accretion of impact melt products [1,2]. These processes produce surface-correlated nanophase Feo, host grain amorphization, formation of surface patinas and other complex changes [1,2]. What is less well understood is how these changes are reflected directly at the surface, defined as the outermost 1-5 atomic monolayers, a region not easily chemically characterized by TEM. We are currently employing X-ray Photoelectron Spectroscopy (XPS) to study the surface chemistry of lunar soil samples that have been previously studied by TEM. This work includes modification of the grain surfaces by in situ irradiation with ions at solar wind energies to better understand how irradiated surfaces in lunar grains change their chemistry once exposed to ambient conditions on earth.

  15. Plume Impingement to the Lunar Surface: A Challenging Problem for DSMC

    Science.gov (United States)

    Lumpkin, Forrest; Marichalar, Jermiah; Piplica, Anthony

    2007-01-01

    The President's Vision for Space Exploration calls for the return of human exploration of the Moon. The plans are ambitious and call for the creation of a lunar outpost. Lunar Landers will therefore be required to land near predeployed hardware, and the dust storm created by the Lunar Lander's plume impingement to the lunar surface presents a hazard. Knowledge of the number density, size distribution, and velocity of the grains in the dust cloud entrained into the flow is needing to develop mitigation strategies. An initial step to acquire such knowledge is simulating the associated plume impingement flow field. The following paper presents results from a loosely coupled continuum flow solver/Direct Simulation Monte Carlo (DSMC) technique for simulating the plume impingement of the Apollo Lunar module on the lunar surface. These cases were chosen for initial study to allow for comparison with available Apollo video. The relatively high engine thrust and the desire to simulate interesting cases near touchdown result in flow that is nearly entirely continuum. The DSMC region of the flow field was simulated using NASA's DSMC Analysis Code (DAC) and must begin upstream of the impingement shock for the loosely coupled technique to succeed. It was therefore impossible to achieve mean free path resolution with a reasonable number of molecules (say 100 million) as is shown. In order to mitigate accuracy and performance issues when using such large cells, advanced techniques such as collision limiting and nearest neighbor collisions were employed. The final paper will assess the benefits and shortcomings of such techniques. In addition, the effects of plume orientation, plume altitude, and lunar topography, such as craters, on the flow field, the surface pressure distribution, and the surface shear stress distribution are presented.

  16. Surface erosion and sedimentation caused by ejecta from the lunar crater Tycho

    Science.gov (United States)

    Shkuratov, Y.; Basilevsky, A.; Kaydash, V.; Ivanov, B.; Korokhin, V.; Videen, G.

    2018-02-01

    We use Kaguya MI images acquired at wavelengths 415, 750, and 950 nm to map TiO2 and FeO content and the parameter of optical maturity OMAT in lunar regions Lubiniezky E and Taurus-Littrow with a spatial resolution of 20 m using the Lucey method [Lucey et al., JGR 2000, 105. 20,297]. We show that some ejecta from large craters, such as Tycho and Copernicus may cause lunar surface erosion, transportation of the eroded material and its sedimentation. The traces of the erosion resemble wind tails observed on Earth, Mars, and Venus, although the Moon has no atmosphere. The highland material of the local topographic prominences could be mobilized by Tycho's granolometrically fine ejecta and caused by its transportation along the ejecta way to adjacent mare areas and subsequent deposition. The tails of mobilized material reveal lower abundances of Ti and Fe than the surrounding mare surface. We have concluded that high-Ti streaks also seen in the Lubiniezky E site, which show unusual combinations of the TiO2 and FeO content on the correlation diagram, could be the result of erosion by Tycho's ejecta too. In these locations, Tycho's material did not form a consolidated deposit, but resulted in erosion of the mare surface material that became intermixed, consequently, diluting the ejecta. The Taurus-Littrow did provide evidence of the mechanical effect of Tycho's ejecta on the local landforms (landslide, secondary craters) and do not show the compositional signature of Tycho's ejecta probably due to intermixing with local materials and dilution.

  17. Lunar surface remanent magnetic fields detected by the electron reflection method

    Science.gov (United States)

    Lin, R. P.; Anderson, K. A.; Bush, R.; Mcguire, R. E.; Mccoy, J. E.

    1976-01-01

    We present maps of the lunar surface remanent magnetic fields detected by the electron reflection method. These maps provide substantial coverage of the latitude band from 30 N southward to 30 S with a resolution of about 40 km and a sensitivity of about 0.2 gamma at the lunar surface. Regions of remanent magnetization are observed ranging in size from the resolution limit of 1.25 deg to above approximately 60 deg. The largest contiguous region fills the Big Backside Basin where it is intersected by the spacecraft orbital tracks. Preliminary analyses of the maps show that the source regions of lunar limb compressions correspond to regions of strong surface magnetism, and that there does not appear to be sharply discontinuous magnetization at the edges of maria. We also analyze the electron reflection observations to obtain information on the direction and distribution of magnetization in the Van de Graaff anomaly region.

  18. Lunar and planetary surface conditions advances in space science and technology

    CERN Document Server

    Weil, Nicholas A

    1965-01-01

    Lunar and Planetary Surface Conditions considers the inferential knowledge concerning the surfaces of the Moon and the planetary companions in the Solar System. The information presented in this four-chapter book is based on remote observations and measurements from the vantage point of Earth and on the results obtained from accelerated space program of the United States and U.S.S.R. Chapter 1 presents the prevalent hypotheses on the origin and age of the Solar System, followed by a brief description of the methods and feasibility of information acquisition concerning lunar and planetary data,

  19. LUNAR SURFACE AND DUST GRAIN POTENTIALS DURING THE EARTH’S MAGNETOSPHERE CROSSING

    Energy Technology Data Exchange (ETDEWEB)

    Vaverka, J.; Richterová, I.; Pavlu, J.; Šafránková, J.; Němeček, Z., E-mail: jana.safrankova@mff.cuni.cz [Department of Surface and Plasma Science, Faculty of Mathematics and Physics, Charles University in Prague, V Holešovičkách 2, 180 00 Prague (Czech Republic)

    2016-07-10

    Interaction between the lunar surface and the solar UV radiation and surrounding plasma environment leads to its charging by different processes like photoemission, collection of charged particles, or secondary electron emission (SEE). Whereas the photoemission depends only on the angle between the surface and direction to the Sun and varies only slowly, plasma parameters can change rapidly as the Moon orbits around the Earth. This paper presents numerical simulations of one Moon pass through the magnetospheric tail including the real plasma parameters measured by THEMIS as an input. The calculations are concentrated on different charges of the lunar surface itself and a dust grain lifted above this surface. Our estimations show that (1) the SEE leads to a positive charging of parts of the lunar surface even in the magnetosphere, where a high negative potential is expected; (2) the SEE is generally more important for isolated dust grains than for the lunar surface covered by these grains; and (3) the time constant of charging of dust grains depends on their diameter being of the order of hours for sub-micrometer grains. In view of these results, we discuss the conditions under which and the areas where a levitation of the lifted dust grains could be observed.

  20. A Basic LEGO Reactor Design for the Provision of Lunar Surface Power

    International Nuclear Information System (INIS)

    John Darrell Bess

    2008-01-01

    A final design has been established for a basic Lunar Evolutionary Growth-Optimized (LEGO) Reactor using current and near-term technologies. The LEGO Reactor is a modular, fast-fission, heatpipe-cooled, clustered-reactor system for lunar-surface power generation. The reactor is divided into subcritical units that can be safely launched with lunar shipments from Earth, and then emplaced directly into holes drilled into the lunar regolith to form a critical reactor assembly. The regolith would not just provide radiation shielding, but serve as neutron-reflector material as well. The reactor subunits are to be manufactured using proven and tested materials for use in radiation environments, such as uranium-dioxide fuel, stainless-steel cladding and structural support, and liquid-sodium heatpipes. The LEGO Reactor system promotes reliability, safety, and ease of manufacture and testing at the cost of an increase in launch mass per overall rated power level and a reduction in neutron economy when compared to a single-reactor system. A single unshielded LEGO Reactor subunit has an estimated mass of approximately 448 kg and provides approximately 5 kWe. The overall envelope for a single subunit with fully extended radiator panels has a height of 8.77 m and a diameter of 0.50 m. Six subunits could provide sufficient power generation throughout the initial stages of establishing a lunar outpost. Portions of the reactor may be neutronically decoupled to allow for reduced power production during unmanned periods of base operations. During later stages of lunar-base development, additional subunits may be emplaced and coupled into the existing LEGO Reactor network, subject to lunar base power demand. Improvements in reactor control methods, fuel form and matrix, shielding, as well as power conversion and heat rejection techniques can help generate an even more competitive LEGO Reactor design. Further modifications in the design could provide power generative opportunities for

  1. Evaluation of Sulfur 'Concrete' for Use as a Construction Material on the Lunar Surface

    Science.gov (United States)

    Grugel, R. N.

    2008-01-01

    Combining molten sulfur with any number of aggregate materials forms, when solid, a mixture having attributes similar, if not better, to conventional water-based concrete. As a result the use of sulfur "concrete" on Earth is well established, particularly in corrosive environments. Consequently, discovery of troilite (FeS) on the lunar surface prompted numerous scenarios about its reduction to elemental sulfur for use, in combination with lunar regolith, as a potential construction material; not requiring water, a precious resource, for its manufacture is an obvious advantage. However, little is known about the viability of sulfur concrete in an environment typified by extreme temperatures and essentially no atmosphere. The experimental work presented here evaluates the response of pure sulfur and sulfur concrete subjected to laboratory conditions that approach those expected on the lunar surface, the results suggesting a narrow window of application.

  2. Delay/Disruption Tolerant Networks (DTN): Testing and Demonstration for Lunar Surface Applications

    Science.gov (United States)

    2009-01-01

    This slide presentation reviews the testing of the Delay/Disruption Tolerant Network (DTN) designed for use with Lunar Surface applications. This is being done through the DTN experimental Network (DEN), that permit access and testing by other NASA centers, DTN team members and protocol developers. The objective of this work is to demonstrate DTN for high return applications in lunar scenarios, provide DEN connectivity with analogs of Constellation elements, emulators, and other resources from DTN Team Members, serve as a wireless communications staging ground for remote analog excursions and enable testing of detailed communication scenarios and evaluation of network performance. Three scenarios for DTN on the Lunar surface are reviewed: Motion imagery, Voice and sensor telemetry, and Navigation telemetry.

  3. AN INTEGRATED PHOTOGRAMMETRIC AND PHOTOCLINOMETRIC APPROACH FOR PIXEL-RESOLUTION 3D MODELLING OF LUNAR SURFACE

    Directory of Open Access Journals (Sweden)

    W. C. Liu

    2018-04-01

    Full Text Available High-resolution 3D modelling of lunar surface is important for lunar scientific research and exploration missions. Photogrammetry is known for 3D mapping and modelling from a pair of stereo images based on dense image matching. However dense matching may fail in poorly textured areas and in situations when the image pair has large illumination differences. As a result, the actual achievable spatial resolution of the 3D model from photogrammetry is limited by the performance of dense image matching. On the other hand, photoclinometry (i.e., shape from shading is characterised by its ability to recover pixel-wise surface shapes based on image intensity and imaging conditions such as illumination and viewing directions. More robust shape reconstruction through photoclinometry can be achieved by incorporating images acquired under different illumination conditions (i.e., photometric stereo. Introducing photoclinometry into photogrammetric processing can therefore effectively increase the achievable resolution of the mapping result while maintaining its overall accuracy. This research presents an integrated photogrammetric and photoclinometric approach for pixel-resolution 3D modelling of the lunar surface. First, photoclinometry is interacted with stereo image matching to create robust and spatially well distributed dense conjugate points. Then, based on the 3D point cloud derived from photogrammetric processing of the dense conjugate points, photoclinometry is further introduced to derive the 3D positions of the unmatched points and to refine the final point cloud. The approach is able to produce one 3D point for each image pixel within the overlapping area of the stereo pair so that to obtain pixel-resolution 3D models. Experiments using the Lunar Reconnaissance Orbiter Camera - Narrow Angle Camera (LROC NAC images show the superior performances of the approach compared with traditional photogrammetric technique. The results and findings from this

  4. SiGe Based Low Temperature Electronics for Lunar Surface Applications

    Science.gov (United States)

    Mojarradi, Mohammad M.; Kolawa, Elizabeth; Blalock, Benjamin; Cressler, John

    2012-01-01

    The temperature at the permanently shadowed regions of the moon's surface is approximately -240 C. Other areas of the lunar surface experience temperatures that vary between 120 C and -180 C during the day and night respectively. To protect against the large temperature variations of the moon surface, traditional electronics used in lunar robotics systems are placed inside a thermally controlled housing which is bulky, consumes power and adds complexity to the integration and test. SiGe Based electronics have the capability to operate over wide temperature range like that of the lunar surface. Deploying low temperature SiGe electronics in a lander platform can minimize the need for the central thermal protection system and enable the development of a new generation of landers and mobility platforms with highly efficient distributed architecture. For the past five years a team consisting of NASA, university and industry researchers has been examining the low temperature and wide temperature characteristic of SiGe based transistors for developing electronics for wide temperature needs of NASA environments such as the Moon, Titan, Mars and Europa. This presentation reports on the status of the development of wide temperature SiGe based electronics for the landers and lunar surface mobility systems.

  5. Lunar ash flows - Isothermal approximation.

    Science.gov (United States)

    Pai, S. I.; Hsieh, T.; O'Keefe, J. A.

    1972-01-01

    Suggestion of the ash flow mechanism as one of the major processes required to account for some features of lunar soil. First the observational background and the gardening hypothesis are reviewed, and the shortcomings of the gardening hypothesis are shown. Then a general description of the lunar ash flow is given, and a simple mathematical model of the isothermal lunar ash flow is worked out with numerical examples to show the differences between the lunar and the terrestrial ash flow. The important parameters of the ash flow process are isolated and analyzed. It appears that the lunar surface layer in the maria is not a residual mantle rock (regolith) but a series of ash flows due, at least in part, to great meteorite impacts. The possibility of a volcanic contribution is not excluded. Some further analytic research on lunar ash flows is recommended.

  6. Reference reactor module for NASA's lunar surface fission power system

    Energy Technology Data Exchange (ETDEWEB)

    Poston, David I [Los Alamos National Laboratory; Kapernick, Richard J [Los Alamos National Laboratory; Dixon, David D [Los Alamos National Laboratory; Werner, James [INL; Qualls, Louis [ORNL; Radel, Ross [SNL

    2009-01-01

    Surface fission power systems on the Moon and Mars may provide the first US application of fission reactor technology in space since 1965. The Affordable Fission Surface Power System (AFSPS) study was completed by NASA/DOE to determine the cost of a modest performance, low-technical risk surface power system. The AFSPS concept is now being further developed within the Fission Surface Power (FSP) Project, which is a near-term technology program to demonstrate system-level TRL-6 by 2013. This paper describes the reference FSP reactor module concept, which is designed to provide a net power of 40 kWe for 8 years on the lunar surface; note, the system has been designed with technologies that are fully compatible with a Martian surface application. The reactor concept uses stainless-steel based. UO{sub 2}-fueled, pumped-NaK fission reactor coupled to free-piston Stirling converters. The reactor shielding approach utilizes both in-situ and launched shielding to keep the dose to astronauts much lower than the natural background radiation on the lunar surface. The ultimate goal of this work is to provide a 'workhorse' power system that NASA can utilize in near-term and future Lunar and Martian mission architectures, with the eventual capability to evolve to very high power, low mass systems, for either surface, deep space, and/or orbital missions.

  7. Distillation and Air Stripping Designs for the Lunar Surface

    Science.gov (United States)

    Boul, Peter J.; Lange, Kevin E.; Conger, Bruce; Anderson, Molly

    2009-01-01

    Air stripping and distillation are two different gravity-based methods, which may be applied to the purification of wastewater on the lunar base. These gravity-based solutions to water processing are robust physical separation techniques, which may be advantageous to many other techniques for their simplicity in design and operation. The two techniques can be used in conjunction with each other to obtain high purity water. The components and feed compositions for modeling waste water streams are presented in conjunction with the Aspen property system for traditional stage distillation models and air stripping models. While the individual components for each of the waste streams will vary naturally within certain bounds, an analog model for waste water processing is suggested based on typical concentration ranges for these components. Target purity levels for the for recycled water are determined for each individual component based on NASA s required maximum contaminant levels for potable water Distillation processes are modeled separately and in tandem with air stripping to demonstrate the potential effectiveness and utility of these methods in recycling wastewater on the Moon. Optimum parameters such as reflux ratio, feed stage location, and processing rates are determined with respect to the power consumption of the process. Multistage distillation is evaluated for components in wastewater to determine the minimum number of stages necessary for each of 65 components in humidity condensate and urine wastewater mixed streams. Components of the wastewater streams are ranked by Henry s Law Constant and the suitability of air stripping in the purification of wastewater in terms of component removal is evaluated. Scaling factors for distillation and air stripping columns are presented to account for the difference in the lunar gravitation environment. Commercially available distillation and air stripping units which are considered suitable for Exploration Life Support

  8. Widespread distribution of OH/H2O on the lunar surface inferred from spectral data.

    Science.gov (United States)

    Bandfield, Joshua L; Poston, Michael J; Klima, Rachel L; Edwards, Christopher S

    2018-01-01

    Remote sensing data from lunar orbiters have revealed spectral features consistent with the presence of OH or H 2 O on the lunar surface. Analyses of data from the Moon Mineralogy Mapper spectrometer onboard the Chandryaan-1 spacecraft have suggested that OH/H 2 O is recycled on diurnal timescales and persists only at high latitudes. However, the spatial distribution and temporal variability of the OH/H 2 O, as well as its source, remain uncertain. Here we incorporate a physics-based thermal correction into analysis of reflectance spectra from the Moon Mineralogy Mapper and find that prominent absorption features consistent with OH/H 2 O can be present at all latitudes, local times, and surface types examined. This suggests the widespread presence of OH/H 2 O on the lunar surface without significant diurnal migration. We suggest that the spectra are consistent with the production of OH in space weathered materials by the solar wind implantation of H + and formation of OH at crystal defect sites, as opposed to H 2 O sourced from the lunar interior. Regardless of the specific composition or formation mechanism, we conclude that OH/H 2 O can be present on the Moon under thermal conditions more wide-ranging than previously recognized.

  9. Contributions of solar-wind induced potential sputtering to the lunar surface erosion rate and it's exosphere

    Science.gov (United States)

    Alnussirat, S. T.; Barghouty, A. F.; Edmunson, J. E.; Sabra, M. S.; Rickman, D. L.

    2018-04-01

    Sputtering of lunar regolith by solar-wind protons and heavy ions with kinetic energies of about 1 keV/amu is an important erosive process that affects the lunar surface and exosphere. It plays an important role in changing the chemical composition and thickness of the surface layer, and in introducing material into the exosphere. Kinetic sputtering is well modeled and understood, but understanding of mechanisms of potential sputtering has lagged behind. In this study we differentiate the contributions of potential sputtering from the standard (kinetic) sputtering in changing the chemical composition and erosion rate of the lunar surface. Also we study the contribution of potential sputtering in developing the lunar exosphere. Our results show that potential sputtering enhances the total characteristic sputtering erosion rate by about 44%, and reduces sputtering time scales by the same amount. Potential sputtering also introduces more material into the lunar exosphere.

  10. Modeling Solar-Wind Heavy-Ions' Potential Sputtering of Lunar KREEP Surface

    Science.gov (United States)

    Barghouty, A. F.; Meyer, F. W.; Harris, R. P.; Adams, J. H., Jr.

    2012-01-01

    Recent laboratory data suggest that potential sputtering may be an important weathering mechanism that can affect the composition of both the lunar surface and its tenuous exosphere; its role and implications, however, remain unclear. Using a relatively simple kinetic model, we will demonstrate that solar-wind heavy ions induced sputtering of KREEP surfaces is critical in establishing the timescale of the overall solar-wind sputtering process of the lunar surface. We will also also show that potential sputtering leads to a more pronounced and significant differentiation between depleted and enriched surface elements. We briefly discuss the impacts of enhanced sputtering on the composition of the regolith and the exosphere, as well as of solar-wind sputtering as a source of hydrogen and water on the moon.

  11. Fully Printed, Flexible, Phased Array Antenna for Lunar Surface Communication

    Science.gov (United States)

    Subbaraman, Harish; Hen, Ray T.; Lu, Xuejun; Chen, Maggie Yihong

    2013-01-01

    NASAs future exploration missions focus on the manned exploration of the Moon, Mars, and beyond, which will rely heavily on the development of a reliable communications infrastructure from planetary surface-to-surface, surface-to-orbit, and back to Earth. Flexible antennas are highly desired in many scenarios. Active phased array antennas (active PAAs) with distributed control and processing electronics at the surface of an antenna aperture offer numerous advantages for radar communications. Large-area active PAAs on flexible substrates are of particular interest in NASA s space radars due to their efficient inflatable package that can be rolled up during transportation and deployed in space. Such an inflatable package significantly reduces stowage volume and mass. Because of these performance and packaging advantages, large-area inflatable active PAAs are highly desired in NASA s surface-to-orbit and surface-to-relay communications. To address the issues of flexible electronics, a room-temperature printing process of active phased-array antennas on a flexible Kapton substrate was developed. Field effect transistors (FETs) based on carbon nanotubes (CNTs), with many unique physical properties, were successfully proved feasible for the PAA system. This innovation is a new type of fully inkjet-printable, two-dimensional, high-frequency PAA on a flexible substrate at room temperature. The designed electronic circuit components, such as the FET switches in the phase shifter, metal interconnection lines, microstrip transmission lines, etc., are all printed using a special inkjet printer. Using the developed technology, entire 1x4, 2x2, and 4x4 PAA systems were developed, packaged, and demonstrated at 5.3 GHz. Several key solutions are addressed in this work to solve the fabrication issues. The source/drain contact is developed using droplets of silver ink printed on the source/drain areas prior to applying CNT thin-film. The wet silver ink droplets allow the silver to

  12. Lunar Meteorites: A Global Geochemical Dataset

    Science.gov (United States)

    Zeigler, R. A.; Joy, K. H.; Arai, T.; Gross, J.; Korotev, R. L.; McCubbin, F. M.

    2017-01-01

    To date, the world's meteorite collections contain over 260 lunar meteorite stones representing at least 120 different lunar meteorites. Additionally, there are 20-30 as yet unnamed stones currently in the process of being classified. Collectively these lunar meteorites likely represent 40-50 distinct sampling locations from random locations on the Moon. Although the exact provenance of each individual lunar meteorite is unknown, collectively the lunar meteorites represent the best global average of the lunar crust. The Apollo sites are all within or near the Procellarum KREEP Terrane (PKT), thus lithologies from the PKT are overrepresented in the Apollo sample suite. Nearly all of the lithologies present in the Apollo sample suite are found within the lunar meteorites (high-Ti basalts are a notable exception), and the lunar meteorites contain several lithologies not present in the Apollo sample suite (e.g., magnesian anorthosite). This chapter will not be a sample-by-sample summary of each individual lunar meteorite. Rather, the chapter will summarize the different types of lunar meteorites and their relative abundances, comparing and contrasting the lunar meteorite sample suite with the Apollo sample suite. This chapter will act as one of the introductory chapters to the volume, introducing lunar samples in general and setting the stage for more detailed discussions in later more specialized chapters. The chapter will begin with a description of how lunar meteorites are ejected from the Moon, how deep samples are being excavated from, what the likely pairing relationships are among the lunar meteorite samples, and how the lunar meteorites can help to constrain the impactor flux in the inner solar system. There will be a discussion of the biases inherent to the lunar meteorite sample suite in terms of underrepresented lithologies or regions of the Moon, and an examination of the contamination and limitations of lunar meteorites due to terrestrial weathering. The

  13. Stair-Step Particle Flux Spectra on the Lunar Surface: Evidence for Nonmonotonic Potentials?

    Science.gov (United States)

    Collier, Michael R.; Newheart, Anastasia; Poppe, Andrew R.; Hills, H. Kent; Farrell, William M.

    2016-01-01

    We present examples of unusual "stair-step" differential flux spectra observed by the Apollo 14 Suprathermal Ion Detector Experiment on the lunar dayside surface in Earth's magnetotail. These spectra exhibit a relatively constant differential flux below some cutoff energy and then drop off precipitously, by about an order of magnitude or more, at higher energies. We propose that these spectra result from photoions accelerated on the lunar dayside by nonmonotonic potentials (i.e.,potentials that do not decay to zero monotonically) and present a model for the expected differential flux. The energy of the cutoff and the magnitude of the differential flux are related to the properties of the local space environment and are consistent with the observed flux spectra. If this interpretation is correct, these surface-based ion observations provide a unique perspective that both complements and enhances the conclusions obtained by remote-sensing orbiter observations on the Moon's exospheric and electrostatic properties.

  14. Feasibility Analysis of Liquefying Oxygen Generated from Water Electrolysis Units on Lunar Surface

    Science.gov (United States)

    Jeng, Frank F.

    2009-01-01

    Concepts for liquefying oxygen (O2) generated from water electrolysis subsystems on the Lunar surface were explored. Concepts for O2 liquefaction units capable of generating 1.38 lb/hr (0.63 kg/hr) liquid oxygen (LOX) were developed. Heat and mass balance calculations for the liquefaction concepts were conducted. Stream properties, duties of radiators, heat exchangers and compressors for the selected concepts were calculated and compared.

  15. Lunar Riometry

    Science.gov (United States)

    Lazio, J.; Jones, D. L.; MacDowall, R. J.; Burns, J. O.; Kasper, J. C.

    2011-12-01

    The lunar exosphere is the exemplar of a plasma near the surface of an airless body. Exposed to both the solar and interstellar radiation fields, the lunar exosphere is mostly ionized, and enduring questions regarding its properties include its density and vertical extent and its behavior over time, including modification by landers. Relative ionospheric measurements (riometry) are based on the simple physical principle that electromagnetic waves cannot propagate through a partially or fully ionized medium below the plasma frequency, and riometers have been deployed on the Earth in numerous remote and hostile environments. A multi-frequency riometer on the lunar surface would be able to monitor, in situ, the peak plasma density of the lunar exosphere over time. We describe a concept for a riometer implemented as a secondary science payload on future lunar landers, such as those recommended in the recent Planetary Sciences Decadal Survey report. While the prime mission of such a riometer would be probing the lunar exosphere, our concept would also be capable to measuring the properties of nanometer- to micron-scale dust. The LUNAR consortium is funded by the NASA Lunar Science Institute to investigate concepts for astrophysical observatories on the Moon. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA.

  16. Dependence of Lunar Surface Charging on Solar Wind Plasma Conditions and Solar Irradiation

    Science.gov (United States)

    Stubbs, T. J.; Farrell, W. M.; Halekas, J. S.; Burchill, J. K.; Collier, M. R.; Zimmerman, M. I.; Vondrak, R. R.; Delory, G. T.; Pfaff, R. F.

    2014-01-01

    The surface of the Moon is electrically charged by exposure to solar radiation on its dayside, as well as by the continuous flux of charged particles from the various plasma environments that surround it. An electric potential develops between the lunar surface and ambient plasma, which manifests itself in a near-surface plasma sheath with a scale height of order the Debye length. This study investigates surface charging on the lunar dayside and near-terminator regions in the solar wind, for which the dominant current sources are usually from the pohotoemission of electrons, J(sub p), and the collection of plasma electrons J(sub e) and ions J(sub i). These currents are dependent on the following six parameters: plasma concentration n(sub 0), electron temperature T(sub e), ion temperature T(sub i), bulk flow velocity V, photoemission current at normal incidence J(sub P0), and photo electron temperature T(sub p). Using a numerical model, derived from a set of eleven basic assumptions, the influence of these six parameters on surface charging - characterized by the equilibrium surface potential, Debye length, and surface electric field - is investigated as a function of solar zenith angle. Overall, T(sub e) is the most important parameter, especially near the terminator, while J(sub P0) and T(sub p) dominate over most of the dayside.

  17. A New Moonquake Catalog from Apollo 17 Seismic Data II: Lunar Surface Gravimeter: Implications of Expanding the Passive Seismic Array

    Science.gov (United States)

    Phillips, D.; Dimech, J. L.; Weber, R. C.

    2017-12-01

    Apollo 17's Lunar Surface Gravimeter (LSG) was deployed on the Moon in 1972, and was originally intended to detect gravitational waves as a confirmation of Einstein's general theory of relativity. Due to a design problem, the instrument did not function as intended. However, remotely-issued reconfiguration commands permitted the instrument to act effectively as a passive seismometer. LSG recorded continuously until Sept. 1977, when all surface data recording was terminated. Because the instrument did not meet its primary science objective, little effort was made to archive the data. Most of it was eventually lost, with the exception of data spanning the period March 1976 until Sept. 1977, and a recent investigation demonstrated that LSG data do contain moonquake signals (Kawamura et al., 2015). The addition of useable seismic data at the Apollo 17 site has important implications for event location schemes, which improve with increasing data coverage. All previous seismic event location attempts were limited to the four stations deployed at the Apollo 12, 14, 15, and 16 sites. Apollo 17 extends the functional aperture of the seismic array significantly to the east, permitting more accurate moonquake locations and improved probing of the lunar interior. Using the standard location technique of linearized arrival time inversion through a known velocity model, Kawamura et al. (2015) used moonquake signals detected in the LSG data to refine location estimates for 49 deep moonquake clusters, and constrained new locations for five previously un-located clusters. Recent efforts of the Apollo Lunar Surface Experiments Package Data Recovery Focus Group have recovered some of the previously lost LSG data, spanning the time period April 2, 1975 to June 30, 1975. In this study, we expand Kawamura's analysis to the newly recovered data, which contain over 200 known seismic signals, including deep moonquakes, shallow moonquakes, and meteorite impacts. We have completed initial

  18. Radar studies of the planets. [radar measurements of lunar surface, Mars, Mercury, and Venus

    Science.gov (United States)

    Ingalls, R. P.; Pettengill, G. H.; Rogers, A. E. E.; Sebring, P. B. (Editor); Shapiro, I. I.

    1974-01-01

    The radar measurements phase of the lunar studies involving reflectivity and topographic mapping of the visible lunar surface was ended in December 1972, but studies of the data and production of maps have continued. This work was supported by Manned Spacecraft Center, Houston. Topographic mapping of the equatorial regions of Mars has been carried out during the period of each opposition since that of 1967. The method comprised extended precise traveling time measurements to a small area centered on the subradar point. As measurements continued, planetary motions caused this point to sweep out extensive areas in both latitude and longitude permitting the development of a fairly extensive topographical map in the equatorial region. Radar observations of Mercury and Venus have also been made over the past few years. Refinements of planetary motions, reflectivity maps and determinations of rotation rates have resulted.

  19. Path Loss Prediction Over the Lunar Surface Utilizing a Modified Longley-Rice Irregular Terrain Model

    Science.gov (United States)

    Foore, Larry; Ida, Nathan

    2007-01-01

    This study introduces the use of a modified Longley-Rice irregular terrain model and digital elevation data representative of an analogue lunar site for the prediction of RF path loss over the lunar surface. The results are validated by theoretical models and past Apollo studies. The model is used to approximate the path loss deviation from theoretical attenuation over a reflecting sphere. Analysis of the simulation results provides statistics on the fade depths for frequencies of interest, and correspondingly a method for determining the maximum range of communications for various coverage confidence intervals. Communication system engineers and mission planners are provided a link margin and path loss policy for communication frequencies of interest.

  20. Design and characterization of a low cost CubeSat multi-band optical receiver to map water ice on the lunar surface for the Lunar Flashlight mission

    Science.gov (United States)

    Vinckier, Quentin; Crabtree, Karlton; Paine, Christopher G.; Hayne, Paul O.; Sellar, Glenn R.

    2017-08-01

    Lunar Flashlight is an innovative NASA CubeSat mission dedicated to mapping water ice in the permanently shadowed regions of the Moon, which may act as cold traps for volatiles. To this end, a multi-band reflectometer will be sent to orbit the Moon. This instrument consists of an optical receiver aligned with four lasers, each of which emits sequentially at a different wavelength in the near-infrared between 1 μm and 2 μm. The receiver measures the laser light reflected from the lunar surface; continuum/absorption band ratios are then analyzed to quantify water ice in the illuminated spot. Here, we present the current state of the optical receiver design. To optimize the optical signal-to-noise ratio, we have designed the receiver so as to maximize the laser signal collected, while minimizing the stray light reaching the detector from solarilluminated areas of the lunar surface outside the field-of-view, taking into account the complex lunar topography. Characterization plans are also discussed. This highly mass- and volume-constrained mission will demonstrate several firsts, including being one of the first CubeSats performing science measurements beyond low Earth orbit.

  1. Orbital Disturbance Analysis due to the Lunar Gravitational Potential and Deviation Minimization through the Trajectory Control in Closed Loop

    International Nuclear Information System (INIS)

    Gonçalves, L D; Rocco, E M; De Moraes, R V

    2013-01-01

    A study evaluating the influence due to the lunar gravitational potential, modeled by spherical harmonics, on the gravity acceleration is accomplished according to the model presented in Konopliv (2001). This model provides the components x, y and z for the gravity acceleration at each moment of time along the artificial satellite orbit and it enables to consider the spherical harmonic degree and order up to100. Through a comparison between the gravity acceleration from a central field and the gravity acceleration provided by Konopliv's model, it is obtained the disturbing velocity increment applied to the vehicle. Then, through the inverse problem, the Keplerian elements of perturbed orbit of the satellite are calculated allowing the orbital motion analysis. Transfer maneuvers and orbital correction of lunar satellites are simulated considering the disturbance due to non-uniform gravitational potential of the Moon, utilizing continuous thrust and trajectory control in closed loop. The simulations are performed using the Spacecraft Trajectory Simulator-STRS, Rocco (2008), which evaluate the behavior of the orbital elements, fuel consumption and thrust applied to the satellite over the time

  2. Kaguya observations of the lunar wake in the terrestrial foreshock: Surface potential change by bow-shock reflected ions

    Science.gov (United States)

    Nishino, Masaki N.; Harada, Yuki; Saito, Yoshifumi; Tsunakawa, Hideo; Takahashi, Futoshi; Yokota, Shoichiro; Matsushima, Masaki; Shibuya, Hidetoshi; Shimizu, Hisayoshi

    2017-09-01

    There forms a tenuous region called the wake behind the Moon in the solar wind, and plasma entry/refilling into the wake is a fundamental problem of the lunar plasma science. High-energy ions and electrons in the foreshock of the Earth's magnetosphere were detected at the lunar surface in the Apollo era, but their effects on the lunar night-side environment have never been studied. Here we show the first observation of bow-shock reflected protons by Kaguya (SELENE) spacecraft in orbit around the Moon, confirming that solar wind plasma reflected at the terrestrial bow shock can easily access the deepest lunar wake when the Moon stays in the foreshock (We name this mechanism 'type-3 entry'). In a continuous type-3 event, low-energy electron beams from the lunar night-side surface are not obvious even though the spacecraft location is magnetically connected to the lunar surface. On the other hand, in an intermittent type-3 entry event, the kinetic energy of upward-going field-aligned electron beams decreases from ∼ 80 eV to ∼ 20 eV or electron beams disappear as the bow-shock reflected ions come accompanied by enhanced downward electrons. According to theoretical treatment based on electric current balance at the lunar surface including secondary electron emission by incident electron and ion impact, we deduce that incident ions would be accompanied by a few to several times higher flux of an incident electron flux, which well fits observed downward fluxes. We conclude that impact by the bow-shock reflected ions and electrons raises the electrostatic potential of the lunar night-side surface.

  3. The evolution of impact basins - Viscous relaxation of topographic relief. [for lunar surface modeling

    Science.gov (United States)

    Solomon, S. C.; Comer, R. P.; Head, J. W.

    1982-01-01

    A topographic profile of the young large lunar basin, Orientale, is presented in order to examine the effects of viscous relaxation on basin topography. Analytical models for viscous flow are considered, showing a wavelength-dependence of time constants for viscous decay on the decrease in viscosity with depth and on the extent of the isostatic compensation of the initial topography. Lunar rheological models which are developed include a half-space model for uniform Newtonian viscosity, density, and gravitational acceleration, a layer over inviscid half space model with material inviscid over geological time scales, and a layer with isostatic compensation where a uniformly viscous layer overlies an inviscid half space of higher density. Greater roughness is concluded, and has been observed, on the moon's dark side due to continued lower temperatures since the time of heavy bombardment.

  4. Kalman filter application to mitigate the errors in the trajectory simulations due to the lunar gravitational model uncertainty

    International Nuclear Information System (INIS)

    Gonçalves, L D; Rocco, E M; De Moraes, R V; Kuga, H K

    2015-01-01

    This paper aims to simulate part of the orbital trajectory of Lunar Prospector mission to analyze the relevance of using a Kalman filter to estimate the trajectory. For this study it is considered the disturbance due to the lunar gravitational potential using one of the most recent models, the LP100K model, which is based on spherical harmonics, and considers the maximum degree and order up to the value 100. In order to simplify the expression of the gravitational potential and, consequently, to reduce the computational effort required in the simulation, in some cases, lower values for degree and order are used. Following this aim, it is made an analysis of the inserted error in the simulations when using such values of degree and order to propagate the spacecraft trajectory and control. This analysis was done using the standard deviation that characterizes the uncertainty for each one of the values of the degree and order used in LP100K model for the satellite orbit. With knowledge of the uncertainty of the gravity model adopted, lunar orbital trajectory simulations may be accomplished considering these values of uncertainty. Furthermore, it was also used a Kalman filter, where is considered the sensor's uncertainty that defines the satellite position at each step of the simulation and the uncertainty of the model, by means of the characteristic variance of the truncated gravity model. Thus, this procedure represents an effort to approximate the results obtained using lower values for the degree and order of the spherical harmonics, to the results that would be attained if the maximum accuracy of the model LP100K were adopted. Also a comparison is made between the error in the satellite position in the situation in which the Kalman filter is used and the situation in which the filter is not used. The data for the comparison were obtained from the standard deviation in the velocity increment of the space vehicle. (paper)

  5. Climatic change due to land surface alterations

    Energy Technology Data Exchange (ETDEWEB)

    Franchito, S.H.; Rao, V.B.

    1992-01-01

    A primitive equations global zonally averaged climate model is developed. The model includes biofeedback mechanisms. For the Northern Hemisphere the parameterization of biofeedback mechanisms is similar to that used by Gutman et al. For the Southern Hemisphere new parameterizations are derived. The model simulates reasonably well the mean annual zonally averaged climate and geobotanic zones. Deforestation, desertification, and irrigation experiments are performed. In the case of deforestation and desertification there is a reduction in the surface net radiation, evaporation, and precipitation and an increase in the surface temperature. In the case of irrigation experiment opposite changes occurred. In all the cases considered the changes in evapotranspiration overcome the effect of surface albedo modification. In all the experiments changes are smaller in the Southern Hemisphere.

  6. Multi-rover navigation on the lunar surface

    Science.gov (United States)

    Dabrowski, Borys; Banaszkiewicz, Marek

    2008-07-01

    The paper presents a method of determination an accurate position of a target (rover, immobile sensor, astronaut) on surface of the Moon or other celestial body devoid of navigation infrastructure (like Global Positioning System), by using a group of self-calibrating rovers, which serves as mobile reference points. The rovers are equipped with low-precision clocks synchronized by external broadcasting signal, to measure the moments of receiving radio signals sent by localized target. Based on the registered times, distances between transmitter and receivers installed on beacons are calculated. Each rover determines and corrects its own absolute position and orientation by using odometry navigation and measurements of relative distances and angles to other mobile reference points. Accuracy of navigation has been improved by the use of a calibration algorithm based on the extended Kalman filter, which uses internal encoder readings as inputs and relative measurements of distances and orientations between beacons as feedback information. The key idea in obtaining reliable values of absolute position and orientation of beacons is to first calibrate one of the rovers, using the remaining ones as reference points and then allow the whole group to move together and calibrate all the rovers in-motion. We consider a number of cases, in which basic modeling parameters such as terrain roughness, formation size and shape as well as availability of distance and angle measurements are varied.

  7. Lunar magnetism

    Science.gov (United States)

    Hood, L. L.; Sonett, C. P.; Srnka, L. J.

    1984-01-01

    Aspects of lunar paleomagnetic and electromagnetic sounding results which appear inconsistent with the hypothesis that an ancient core dynamo was the dominant source of the observed crustal magnetism are discussed. Evidence is summarized involving a correlation between observed magnetic anomalies and ejecta blankets from impact events which indicates the possible importance of local mechanisms involving meteoroid impact processes in generating strong magnetic fields at the lunar surface. A reply is given to the latter argument which also presents recent evidence of a lunar iron core.

  8. Assessment of Scheduling and Plan Execution of Apollo 14 Lunar Surface Operations

    Science.gov (United States)

    Marquez, Jessica J.

    2010-01-01

    Although over forty years have passed since first landing on the Moon, there is not yet a comprehensive, quantitative assessment of Apollo extravehicular activities (EVAs). Quantitatively evaluating lunar EVAs will provide a better understanding of the challenges involved with surface operations. This first evaluation of a surface EVA centers on comparing the planned and the as-ran timeline, specifically collecting data on discrepancies between durations that were estimated versus executed. Differences were summarized by task categories in order to gain insight as to the type of surface operation activities that were most challenging. One Apollo 14 EVA was assessed utilizing the described methodology. Selected metrics and task categorizations were effective, and limitations to this process were identified.

  9. Observation of the lunar surface by GRS in KAGUYA (SELENE). To solve mystery of moon and manned landing

    International Nuclear Information System (INIS)

    Hasebe, Nobuyuki; Kobayashi, Shingo

    2009-01-01

    The researches, resources and environment of the moon are reported. The main results such as the magma ocean hypothesis by the Apollo program, the lunar map by Clementine probe and the concentration of Th in the moon by Lunar Prospector probe are explained. B.L. Jolliff et al. proposed the moon consisted of three areas such as the Procellarum KREEP Terrane (PKT), South-Pole Aitken Terrane (SPAT) and Feldspathic Highland Terrane (FHT). The radiations on the lunar surface contain the galactic cosmic ray, solar particle event, second particles produced by interaction between the high energy particles and the materials on the lunar surface, and natural radioactivity from U, Th and K. The gamma ray spectrum on the lunar surface observed by Kaguya gamma ray spectrometer (KGRS) showed the very sharp spectrum of O, Mg, Al, Si, Ca, K, Ti, Fe, Th and U. The distribution of Th in PKT, SPAT and FHT was shown. The outline of KGRS, the energy resolutions of many kinds of gamma ray spectrometers, and the gamma ray energies of main elements are illustrated. (S.Y.)

  10. On the Search for the Amino Acids on the Lunar Surface as it Relates to Other Extraterrestrial Bodies

    Science.gov (United States)

    Hoover, Richard B.; Kolb, Vera M.

    2009-01-01

    The early search for the amino acids on the lunar surface fines indicated such a low amount of the amino acids that it was deemed insignifi cant. While the later studies seemed to depart in some ways from the earlier results, they were not pursued. In this paper we critically ev aluate the results from the Apollo missions from the new perspective with considerations of the sensitivity of the instrumentation availabl e at the time. We discuss the possible relevance of the lunar results to the findings of the amino acids on the surfaces of other extraterrestrial bodies, such as Mars.

  11. Dual-purpose self-deliverable lunar surface PV electrical power system

    Science.gov (United States)

    Arnold, Jack H.; Harris, David W.; Cross, Eldon R.; Flood, Dennis J.

    1991-01-01

    A safe haven and work supported PV power systems on the lunar surface will likely be required by NASA in support of the manned outpost scheduled for the post-2000 lunar/Mars exploration and colonization initiative. Initial system modeling and computer analysis shows that the concept is workable and contains no major high risk technology issues which cannot be resolved in the circa 2000 to 2025 timeframe. A specific selection of the best suited type of electric thruster has not been done; the initial modeling was done using an ion thruster, but Rocketdyne must also evaluate arc and resisto-jets before a final design can be formulated. As a general observation, it appears that such a system can deliver itself to the Moon using many system elements that must be transported as dead payload mass in more conventional delivery modes. It further appears that a larger power system providing a much higher safe haven power level is feasible if this delivery system is implemented, perhaps even sufficient to permit resource prospecting and/or lab experimentation. The concept permits growth and can be expanded to include cargo transport such as habitat and working modules. In short, the combined payload could be manned soon after landing and checkout. NASA has expended substantial resources in the development of electric propulsion concepts and hardware that can be applied to a lunar transport system such as described herein. In short, the paper may represent a viable mission on which previous investments play an invaluable role. A more comprehensive technical paper which embodies second generation analysis and system size will be prepared for near-term presentation.

  12. Lunar heat-flow experiment

    Science.gov (United States)

    Langseth, M. G.

    1977-01-01

    The principal components of the experiment were probes, each with twelve thermometers of exceptional accuracy and stability, that recorded temperature variations at the surface and in the regolith down to 2.5 m. The Apollo 15 experiment and the Apollo 17 probes recorded lunar surface and subsurface temperatures. These data provided a unique and valuable history of the interaction of solar energy with lunar surface and the effects of heat flowing from the deep interior out through the surface of the moon. The interpretation of these data resulted in a clearer definition of the thermal and mechanical properties of the upper two meters of lunar regolith, direct measurements of the gradient in mean temperature due to heat flow from the interior and a determination of the heat flow at the Apollo 15 and Apollo 17 sites.

  13. Hybrid Heat Pipes for Lunar and Martian Surface and High Heat Flux Space Applications

    Science.gov (United States)

    Ababneh, Mohammed T.; Tarau, Calin; Anderson, William G.; Farmer, Jeffery T.; Alvarez-Hernandez, Angel R.

    2016-01-01

    Novel hybrid wick heat pipes are developed to operate against gravity on planetary surfaces, operate in space carrying power over long distances and act as thermosyphons on the planetary surface for Lunar and Martian landers and rovers. These hybrid heat pipes will be capable of operating at the higher heat flux requirements expected in NASA's future spacecraft and on the next generation of polar rovers and equatorial landers. In addition, the sintered evaporator wicks mitigate the start-up problems in vertical gravity aided heat pipes because of large number of nucleation sites in wicks which will allow easy boiling initiation. ACT, NASA Marshall Space Flight Center, and NASA Johnson Space Center, are working together on the Advanced Passive Thermal experiment (APTx) to test and validate the operation of a hybrid wick VCHP with warm reservoir and HiK"TM" plates in microgravity environment on the ISS.

  14. Mass loading of the Earth's magnetosphere by micron size lunar ejecta. 1: Ejecta production and orbital dynamics in cislunar space

    Science.gov (United States)

    Alexander, W. M.; Tanner, W. G.; Anz, P. D.; Chen, A. L.

    1986-01-01

    Particulate matter possessing lunar escape velocity sufficient to enhance the cislunar meteroid flux was investigated. While the interplanetary flux was extensively studied, lunar ejecta created by the impact of this material on the lunar surface is only now being studied. Two recently reported flux models are employed to calculate the total mass impacting the lunar surface due to sporadic meteor flux. There is ample evidence to support the contention that the sporadic interplanetary meteoroid flux enhances the meteroid flux of cislunar space through the creation of micron and submicron lunar ejecta with lunar escape velocity.

  15. Design and Testing of a Prototype Lunar or Planetary Surface Landing Research Vehicle (LPSLRV)

    Science.gov (United States)

    Murphy, Gloria A.

    2010-01-01

    This handbook describes a two-semester senior design course sponsored by the NASA Office of Education, the Exploration Systems Mission Directorate (ESMD), and the NASA Space Grant Consortium. The course was developed and implemented by the Mechanical and Aerospace Engineering Department (MAE) at Utah State University. The course final outcome is a packaged senior design course that can be readily incorporated into the instructional curriculum at universities across the country. The course materials adhere to the standards of the Accreditation Board for Engineering and Technology (ABET), and is constructed to be relevant to key research areas identified by ESMD. The design project challenged students to apply systems engineering concepts to define research and training requirements for a terrestrial-based lunar landing simulator. This project developed a flying prototype for a Lunar or Planetary Surface Landing Research Vehicle (LPSRV). Per NASA specifications the concept accounts for reduced lunar gravity, and allows the terminal stage of lunar descent to be flown either by remote pilot or autonomously. This free-flying platform was designed to be sufficiently-flexible to allow both sensor evaluation and pilot training. This handbook outlines the course materials, describes the systems engineering processes developed to facilitate design fabrication, integration, and testing. This handbook presents sufficient details of the final design configuration to allow an independent group to reproduce the design. The design evolution and details regarding the verification testing used to characterize the system are presented in a separate project final design report. Details of the experimental apparatus used for system characterization may be found in Appendix F, G, and I of that report. A brief summary of the ground testing and systems verification is also included in Appendix A of this report. Details of the flight tests will be documented in a separate flight test

  16. Analysis of Stationary, Photovoltaic-based Surface Power System Designs at the Lunar South Pole

    Science.gov (United States)

    Freeh, Joshua E.

    2009-01-01

    Combinations of solar arrays and either batteries or regenerative fuel cells are analyzed for a surface power system module at the lunar south pole. The systems are required to produce 5 kW of net electrical power in sunlight and 2 kW of net electrical power during lunar night periods for a 10-year period between 2020 and 2030. Systems-level models for energy conservation, performance, degradation, and mass are used to compare to various systems. The sensitivities of important and/or uncertain variables including battery specific energy, fuel cell operating voltage, and DC-DC converter efficiency are compared to better understand the system. Switching unit efficiency, battery specific energy, and fuel cell operating voltage appear to be important system-level variables for this system. With reasonably sized solar arrays, the regenerative fuel cell system has significantly lower mass than the battery system based on the requirements and assumptions made herein. The total operational time is estimated at about 10,000 hours in battery discharge/fuel cell mode and about 4,000 and 8,000 hours for the battery charge and electrolyzer modes, respectively. The estimated number of significant depth-of-discharge cycles for either energy storage system is less than 100 for the 10-year period.

  17. A comparison of two systems for lunar surface remote and mobile power applications

    International Nuclear Information System (INIS)

    Determan, W.R.; Otting, W.D.; Hunt, M.E.

    1993-01-01

    The free piston Stirling engine (FPSE) is now being developed by Mechanical Technology Incorporated (MTI) and NASA-LeRC for space power applications. Some conceptualizations of an isotope powered FPSE have been proposed. The performance characteristics of the proposed 2.5-kWe Stirling Isotope Power (STIP) system were developed for lunar surface remote and mobile applications. The Stirling system configuration uses a nonredundant power conversion system coupled to an annular heat source assembly (HSA) using an array of sodium heat pipes which transfer energy from the annular general-purpose heat source (GPHS) stack within the HSA to the Stirling heater head. The Stirling engine uses a dual-opposed piston design with heater head coupling. The engine coolers are connected to a single-pumped coolant loop, which rejects the cycle's waste heat to a radiator. Quantitative information, such as mass, area, and efficiency, are reported for the system. The results of a qualitative evaluation of the proposed STIP system against the desirable attributes of a lunar-based isotope power system are presented. Alternate configurations are also presented

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

    Science.gov (United States)

    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.

  19. A Study of an Optical Lunar Surface Communications Network with High Bandwidth Direct to Earth Link

    Science.gov (United States)

    Wilson, K.; Biswas, A.; Schoolcraft, J.

    2011-01-01

    Analyzed optical DTE (direct to earth) and lunar relay satellite link analyses, greater than 200 Mbps downlink to 1-m Earth receiver and greater than 1 Mbps uplink achieved with mobile 5-cm lunar transceiver, greater than 1Gbps downlink and greater than 10 Mpbs uplink achieved with 10-cm stationary lunar transceiver, MITLL (MIT Lincoln Laboratory) 2013 LLCD (Lunar Laser Communications Demonstration) plans to demonstrate 622 Mbps downlink with 20 Mbps uplink between lunar orbiter and ground station; Identified top five technology challenges to deploying lunar optical network, Performed preliminary experiments on two of challenges: (i) lunar dust removal and (ii)DTN over optical carrier, Exploring opportunities to evaluate DTN (delay-tolerant networking) over optical link in a multi-node network e.g. Desert RATS.

  20. A Study of Parallels Between Antarctica South Pole Traverse Equipment and Lunar/Mars Surface Systems

    Science.gov (United States)

    Mueller, Robert P.; Hoffman, Stephen, J.; Thur, Paul

    2010-01-01

    The parallels between an actual Antarctica South Pole re-supply traverse conducted by the National Science Foundation (NSF) Office of Polar Programs in 2009 have been studied with respect to the latest mission architecture concepts being generated by the United States National Aeronautics and Space Administration (NASA) for lunar and Mars surface systems scenarios. The challenges faced by both endeavors are similar since they must both deliver equipment and supplies to support operations in an extreme environment with little margin for error in order to be successful. By carefully and closely monitoring the manifesting and operational support equipment lists which will enable this South Pole traverse, functional areas have been identified. The equipment required to support these functions will be listed with relevant properties such as mass, volume, spare parts and maintenance schedules. This equipment will be compared to space systems currently in use and projected to be required to support equivalent and parallel functions in Lunar and Mars missions in order to provide a level of realistic benchmarking. Space operations have historically required significant amounts of support equipment and tools to operate and maintain the space systems that are the primary focus of the mission. By gaining insight and expertise in Antarctic South Pole traverses, space missions can use the experience gained over the last half century of Antarctic operations in order to design for operations, maintenance, dual use, robustness and safety which will result in a more cost effective, user friendly, and lower risk surface system on the Moon and Mars. It is anticipated that the U.S Antarctic Program (USAP) will also realize benefits for this interaction with NASA in at least two areas: an understanding of how NASA plans and carries out its missions and possible improved efficiency through factors such as weight savings, alternative technologies, or modifications in training and

  1. An Evidence-based Approach to Developing a Management Strategy for Medical Contingencies on the Lunar Surface: The NASA/Haughton-Mars Project (HMP) 2006 Lunar Medical Contingency Simulation at Devon Island

    Science.gov (United States)

    Scheuring, R. A.; Jones, J. A.; Lee, P.; Comtois, J. M.; Chappell, S.; Rafiq, A.; Braham, S.; Hodgson, E.; Sullivan, P.; Wilkinson, N.; hide

    2007-01-01

    The lunar architecture for future sortie and outpost missions will require humans to serve on the lunar surface considerably longer than the Apollo moon missions. Although the Apollo crewmembers sustained few injuries during their brief lunar surface activity, injuries did occur and are a concern for the longer lunar stays. Interestingly, lunar medical contingency plans were not developed during Apollo. In order to develop an evidence-base for handling a medical contingency on the lunar surface, a simulation using the moon-Mars analog environment at Devon Island, Nunavut, high Canadian Arctic was conducted. Objectives of this study included developing an effective management strategy for dealing with an incapacitated crewmember on the lunar surface, establishing audio/visual and biomedical data connectivity to multiple centers, testing rescue/extraction hardware and procedures, and evaluating in suit increased oxygen consumption. Methods: A review of the Apollo lunar surface activities and personal communications with Apollo lunar crewmembers provided the knowledge base of plausible scenarios that could potentially injure an astronaut during a lunar extravehicular activity (EVA). Objectives were established to demonstrate stabilization and transfer of an injured crewmember and communication with ground controllers at multiple mission control centers. Results: The project objectives were successfully achieved during the simulation. Among these objectives were extraction from a sloped terrain by a two-member crew in a 1 g analog environment, establishing real-time communication to multiple centers, providing biomedical data to flight controllers and crewmembers, and establishing a medical diagnosis and treatment plan from a remote site. Discussion: The simulation provided evidence for the types of equipment and methods for performing extraction of an injured crewmember from a sloped terrain. Additionally, the necessary communications infrastructure to connect

  2. SECONDARY EMISSION FROM NON-SPHERICAL DUST GRAINS WITH ROUGH SURFACES: APPLICATION TO LUNAR DUST

    International Nuclear Information System (INIS)

    Richterová, I.; Němeček, Z.; Beránek, M.; Šafránková, J.; Pavlů, J.

    2012-01-01

    Electrons impinging on a target can release secondary electrons and/or they can be scattered out of the target. It is well established that the number of escaping electrons per primary electron depends on the target composition and dimensions, the energy, and incidence angle of the primary electrons, but there are suggestions that the target's shape and surface roughness also influence the secondary emission. We present a further modification of the model of secondary electron emission from dust grains which is applied to non-spherical grains and grains with defined surface roughness. It is shown that the non-spherical grains give rise to a larger secondary electron yield, whereas the surface roughness leads to a decrease in the yield. Moreover, these effects can be distinguished: the shape effect is prominent for high primary energies, whereas the surface roughness predominantly affects the yield at the low-energy range. The calculations use the Lunar Highlands Type NU-LHT-2M simulant as a grain material and the results are compared with previously published laboratory and in situ measurements.

  3. Cross-calibration of Medium Resolution Earth Observing Satellites by Using EO-1 Hyperion-derived Spectral Surface Reflectance from "Lunar Cal Sites"

    Science.gov (United States)

    Ungar, S.

    2017-12-01

    Over the past 3 years, the Earth Observing-one (EO-1) Hyperion imaging spectrometer was used to slowly scan the lunar surface at a rate which results in up to 32X oversampling to effectively increase the SNR. Several strategies, including comparison against the USGS RObotic Lunar Observatory (ROLO) mode,l are being employed to estimate the absolute and relative accuracy of the measurement set. There is an existing need to resolve discrepancies as high as 10% between ROLO and solar based calibration of current NASA EOS assets. Although the EO-1 mission was decommissioned at the end of March 2017, the development of a well-characterized exoatmospheric spectral radiometric database, for a range of lunar phase angles surrounding the fully illuminated moon, continues. Initial studies include a comprehensive analysis of the existing 17-year collection of more than 200 monthly lunar acquisitions. Specific lunar surface areas, such as a lunar mare, are being characterized as potential "lunar calibration sites" in terms of their radiometric stability in the presence of lunar nutation and libration. Site specific Hyperion-derived lunar spectral reflectance are being compared against spectrographic measurements made during the Apollo program. Techniques developed through this activity can be employed by future high-quality orbiting imaging spectrometers (such as HyspIRI and EnMap) to further refine calibration accuracies. These techniques will enable the consistent cross calibration of existing and future earth observing systems (spectral and multi-spectral) including those that do not have lunar viewing capability. When direct lunar viewing is not an option for an earth observing asset, orbiting imaging spectrometers can serve as transfer radiometers relating that asset's sensor response to lunar values through near contemporaneous observations of well characterized stable CEOS test sites. Analysis of this dataset will lead to the development of strategies to ensure more

  4. Evaluation of IEEE 802.11g and 802.16 for Lunar Surface Exploration Missions Using MACHETE Simulations

    Science.gov (United States)

    Segui, John; Jennings, Esther; Vyas, Hemali

    2009-01-01

    In this paper, we investigated the suitability of terrestrial wireless networking technologies for lunar surface exploration missions. Specifically, the scenario we considered consisted of two teams of collaborating astronauts, one base station and one rover, where the base station and the rover have the capability of acting as relays. We focused on the evaluation of IEEE 802.11g and IEEE 802.16 protocols, simulating homogeneous 802.11g network, homogeneous 802.16 network, and heterogeneous network using both 802.11g and 802.16. A mix of traffic flows were simulated, including telemetry, caution and warning, voice, command and file transfer. Each traffic type had its own distribution profile, data volume, and priority. We analyzed the loss and delay trade-offs of these wireless protocols with various link-layer options. We observed that 802.16 network managed the channel better than an 802.11g network due to controlled infrastructure and centralized scheduling. However, due to the centralized scheduling, 802.16 also had a longer delay. The heterogeneous (hybrid) of 802.11/802.16 achieved a better balance of performance in terms of data loss and delay compared to using 802.11 or 802.16 alone.

  5. Lunar Flashlight and Other Lunar Cubesats

    Science.gov (United States)

    Cohen, Barbara

    2017-01-01

    Water is a human-exploitable resource. Lunar Flashlight is a Cubesat mission to detect and map lunar surface ice in permanently-shadowed regions of the lunar south pole. EM-1 will carry 13 Cubesat-class missions to further smallsat science and exploration capabilities; much room to infuse LEO cubesat methodology, models, and technology. Exploring the value of concurrent measurements to measure dynamical processes of water sources and sinks.

  6. Lunar Navigation Architecture Design Considerations

    Science.gov (United States)

    D'Souza, Christopher; Getchius, Joel; Holt, Greg; Moreau, Michael

    2009-01-01

    The NASA Constellation Program is aiming to establish a long-term presence on the lunar surface. The Constellation elements (Orion, Altair, Earth Departure Stage, and Ares launch vehicles) will require a lunar navigation architecture for navigation state updates during lunar-class missions. Orion in particular has baselined earth-based ground direct tracking as the primary source for much of its absolute navigation needs. However, due to the uncertainty in the lunar navigation architecture, the Orion program has had to make certain assumptions on the capabilities of such architectures in order to adequately scale the vehicle design trade space. The following paper outlines lunar navigation requirements, the Orion program assumptions, and the impacts of these assumptions to the lunar navigation architecture design. The selection of potential sites was based upon geometric baselines, logistical feasibility, redundancy, and abort support capability. Simulated navigation covariances mapped to entry interface flightpath- angle uncertainties were used to evaluate knowledge errors. A minimum ground station architecture was identified consisting of Goldstone, Madrid, Canberra, Santiago, Hartebeeshoek, Dongora, Hawaii, Guam, and Ascension Island (or the geometric equivalent).

  7. Lunar and Planetary Science XXXV: Moon and Mercury

    Science.gov (United States)

    2004-01-01

    The session" Moon and Mercury" included the following reports:Helium Production of Prompt Neutrinos on the Moon; Vapor Deposition and Solar Wind Implantation on Lunar Soil-Grain Surfaces as Comparable Processes; A New Lunar Geologic Mapping Program; Physical Backgrounds to Measure Instantaneous Spin Components of Terrestrial Planets from Earth with Arcsecond Accuracy; Preliminary Findings of a Study of the Lunar Global Megaregolith; Maps Characterizing the Lunar Regolith Maturity; Probable Model of Anomalies in the Polar Regions of Mercury; Parameters of the Maximum of Positive Polarization of the Moon; Database Structure Development for Space Surveying Results by Moon -Zond Program; CM2-type Micrometeoritic Lunar Winds During the Late Heavy Bombardment; A Comparison of Textural and Chemical Features of Spinel Within Lunar Mare Basalts; The Reiner Gamma Formation as Characterized by Earth-based Photometry at Large Phase Angles; The Significance of the Geometries of Linear Graben for the Widths of Shallow Dike Intrusions on the Moon; Lunar Prospector Data, Surface Roughness and IR Thermal Emission of the Moon; The Influence of a Magma Ocean on the Lunar Global Stress Field Due to Tidal Interaction Between the Earth and Moon; Variations of the Mercurian Photometric Relief; A Model of Positive Polarization of Regolith; Ground Truth and Lunar Global Thorium Map Calibration: Are We There Yet?;and Space Weathering of Apollo 16 Sample 62255: Lunar Rocks as Witness Plates for Deciphering Regolith Formation Processes.

  8. Asymmetric Early Crust-Building Magmatism on the Lunar Nearside Due to KREEP-Induced Melting Point Depression

    Science.gov (United States)

    Elardo, S. M.; Shearer, C. K.; McCuddin, F. M.

    2018-01-01

    The lunar magnesian-suite, or Mg-suite, is a series of ancient plutonic rocks from the lunar crust with ages and compositions indicating that they represent crust-building magmatism occurring immediately after the end of magma ocean crystallization. Samples of the Mg-suite were found at every Apollo landing site except 11 and ubiquitously have geochemical characteristics indicating the involvement of KREEP in their petrogenesis. This observation has led to the suggestion that the presence of the KREEP reservoir under the lunar nearside was responsible for this episode of crust building. The lack of any readily identifiable Mg-suite rocks in meteoritic regolith breccias sourced from outside the Procellarum KREEP Terrane (PKT) seemingly supports this interpretation.

  9. A Brief Survey of Media Access Control, Data Link Layer, and Protocol Technologies for Lunar Surface Communications

    Science.gov (United States)

    Wallett, Thomas M.

    2009-01-01

    This paper surveys and describes some of the existing media access control and data link layer technologies for possible application in lunar surface communications and the advanced wideband Direct Sequence Code Division Multiple Access (DSCDMA) conceptual systems utilizing phased-array technology that will evolve in the next decade. Time Domain Multiple Access (TDMA) and Code Division Multiple Access (CDMA) are standard Media Access Control (MAC) techniques that can be incorporated into lunar surface communications architectures. Another novel hybrid technique that is recently being developed for use with smart antenna technology combines the advantages of CDMA with those of TDMA. The relatively new and sundry wireless LAN data link layer protocols that are continually under development offer distinct advantages for lunar surface applications over the legacy protocols which are not wireless. Also several communication transport and routing protocols can be chosen with characteristics commensurate with smart antenna systems to provide spacecraft communications for links exhibiting high capacity on the surface of the Moon. The proper choices depend on the specific communication requirements.

  10. Lunar Dust Mitigation Screens

    Science.gov (United States)

    Knutson, Shawn; Holloway, Nancy

    With plans for the United States to return to the moon, and establish a sustainable human presence on the lunar surface many issues must be successfully overcome. Lunar dust is one of a number of issues with the potential to create a myriad of problems if not adequately addressed. Samples of dust brought back from Apollo missions show it to be soft, yet sharp and abrasive. The dust consists of a variety of morphologies including spherical, angular blocks, shards, and a number of irregular shapes. One of the main issues with lunar dust is its attraction to stick to anything it comes in contact with (i.e. astronauts, equipment, habitats, etc.). Ionized radiation from the sun strikes the moon's surface and creates an electrostatic charge on the dust. Further, the dust harbors van der Waals forces making it especially difficult to separate once it sticks to a surface. During the Apollo missions, it was discovered that trying to brush the lunar dust from spacesuits was not effective, and rubbing it caused degradation of the suit material. Further, when entering the lunar module after moonwalks, the astronauts noted that the dust was so prolific inside the cabin that they inhaled and ingested it, causing at least one of them, Harrison "Jack" Schmidt, to report irritation of the throat and lungs. It is speculated that the dust could also harm an astronaut's nervous and cardiovascular systems, especially during an extended stay. In addition to health issues, the dust can also cause problems by scouring reflective coatings off of thermal blankets, and roughening surfaces of windows and optics. Further, panels on solar cells and photovoltaics can also be compromised due to dust sticking on the surfaces. Lunar dust has the capacity to penetrate seals, interfere with connectors, as well as mechanisms on digging machines, all of which can lead to problems and failure. To address lunar dust issues, development of electrostatic screens to mitigate dust on sur-faces is currently

  11. Radiation transport of cosmic ray nuclei in lunar material and radiation doses

    International Nuclear Information System (INIS)

    Silberberg, R.; Tsao, C.H.; Adams, J.H. Jr.; Letaw, J.R.

    1985-01-01

    The radiation environment on the lunar surface is inhospitable. The permanent settlers may work ten hours per 24-hour interval for the two-week-long lunar day on the lunar surface, or 20 percent of the total time. At moderate depths below the lunar surface (less than 200 g/sq cm) the flux of secondary neutrons exceeds considerably that in the upper atmosphere of the earth, due to cosmic-ray interactions with lunar material. The annual dose equivalent due to neutrons is about 20 or 25 rem within the upper meter of the lunar surface. The dose equivalent due to gamma rays generated by nuclear interactions near the lunar surface is only on the order of 1 percent of that due to neutrons. However, gamma-ray line emission from excited nuclei and nuclear spallation products generated by cosmic rays near the lunar surface is of considerable interest: these lines permit the partial determination of lunar composition by gamma spectroscopy. 12 references

  12. Lunar Industry & Research Base Concept

    Science.gov (United States)

    Lysenko, J.; Kaliapin, M.; Osinovyy, G.

    2017-09-01

    Currently, all main space industry players, such as Europe, USA, Russia, China, etc., are looking back again at the idea of Moon exploration building there a manned lunar base. Alongside with other world spacefaring nations, Yuzhnoye State Design Office with its long-time development experience, technological and intellectual potential, organized its own conceptual work on development of the Lunar Industry & Research Base. In the frames of conceptual project "Lunar Industrial & Research Base" were formed its appearance, preliminary configuration and infrastructure at different stages of operation, trajectory and flight scheme to the Moon, as well as terms of the project's realization, and main technical characteristics of the systems under development, such as space transportation system for crew and cargo delivery to lunar surface and return to Earth, standardized designs of lunar modules, lunar surface vehicles, etc. The "Lunar Industrial & Research Base" project's preliminary risk assessment has shown a high value of its overall risk due to the lack of reliable information about the Moon, technical risks, long-term development of its elements, very high financial costs and dependence on state support. This points to the fact that it is reasonable to create such a global project in cooperation with other countries. International cooperation will expand the capabilities of any nation, reduce risks and increase the success probability of automated or manned space missions. It is necessary to create and bring into operation practical mechanisms for long-term space exploration on a global scale. One of the ways to do this is to create a multinational agency which would include both state enterprises and private companies.

  13. ANALYSES OF ROCK SURFACE COLOUR CHANGES DUE TO WEATHERING

    OpenAIRE

    GOKAY, Mehmet Kemal

    2018-01-01

    Description parameters of rock masses and minerals include their colours as well. Colours appear in daylight for surfaced rock masses are changing slightly due to weathering layers which have been covering its surface gradually. Healthy human eyes can manage to differentiate visible light spectrum to identify colours of substances including rock masses. Then visible blackish colours of magnetite minerals, reddish colours of Terra- Rosa soils, greenish colours of weathered copper ore, pure whi...

  14. ANALYSES OF ROCK SURFACE COLOUR CHANGES DUE TO WEATHERING

    OpenAIRE

    GÖKAY, Mehmet Kemal

    2018-01-01

    Description parameters of rock masses and minerals include their colours as well. Colours appear in daylight for surfaced rock masses are changing slightly due to weathering layers which have been covering its surface gradually. Healthy human eyes can manage to differentiate visible spectrum to identify the colours of substance including rock masses. Then visible blackish colours of magnetite minerals, reddish colours of Terra- Rosa soils, greenish colours of weathered copper ore, pure white ...

  15. Near-Field Spectral Effects due to Electromagnetic Surface Excitations

    OpenAIRE

    Shchegrov , Andrei ,; Joulain , Karl; Carminati , Rémi; Greffet , Jean-Jacques

    2000-01-01

    International audience; We demonstrate theoretically that the spectra of electromagnetic emission of surface systems can display remarkable differences in the near and the far zones. The spectral changes occur due to the loss of evanescent modes and are especially pronounced for systems which support surface waves. PACS numbers: 78.20. – e, 05.40. – a, 44.40. + a, 87.64.Xx Spectroscopy of electromagnetic radiation is perhaps the most powerful exploration tool employed in natural sciences: ast...

  16. A Comparison of Fission Power System Options for Lunar and Mars Surface Applications

    International Nuclear Information System (INIS)

    Mason, Lee S.

    2006-01-01

    This paper presents a comparison of reactor and power conversion design options for 50 kWe class lunar and Mars surface power applications with scaling from 25 to 200 kWe. Design concepts and integration approaches are provided for three reactor-converter combinations: gas-cooled Brayton, liquid-metal Stirling, and liquid-metal thermoelectric. The study examines the mass and performance of low temperature, stainless steel based reactors and higher temperature refractory reactors. The preferred system implementation approach uses crew-assisted assembly and in-situ radiation shielding via installation of the reactor in an excavated hole. As an alternative, self-deployable system concepts that use earth-delivered, on-board radiation shielding are evaluated. The analyses indicate that among the 50 kWe stainless steel reactor options, the liquid-metal Stirling system provides the lowest mass at about 5300 kg followed by the gas-cooled Brayton at 5700 kg and the liquid-metal thermoelectric at 8400 kg. The use of a higher temperature, refractory reactor favors the gas-cooled Brayton option with a system mass of about 4200 kg as compared to the Stirling and thermoelectric options at 4700 kg and 5600 kg, respectively. The self-deployed concepts with on-board shielding result in a factor of two system mass increase as compared to the in-situ shielded concepts

  17. In Situ Lunar Surface Measurements Via Miniature Gas Chromatography, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Exploration Analysis Group (LEAG) has placed a high priority on determining the nature, distribution and transport of volatiles on the moon. The objective...

  18. Surface Support Systems for Co-Operative and Integrated Human/Robotic Lunar Exploration

    Science.gov (United States)

    Mueller, Robert P.

    2006-01-01

    Human and robotic partnerships to realize space goals can enhance space missions and provide increases in human productivity while decreasing the hazards that the humans are exposed to. For lunar exploration, the harsh environment of the moon and the repetitive nature of the tasks involved with lunar outpost construction, maintenance and operation as well as production tasks associated with in-situ resource utilization, make it highly desirable to use robotic systems in co-operation with human activity. A human lunar outpost is functionally examined and concepts for selected human/robotic tasks are discussed in the context of a lunar outpost which will enable the presence of humans on the moon for extended periods of time.

  19. Thermal System Modeling for Lunar and Martian Surface Regenerative Fuel Cell Systems

    Science.gov (United States)

    Gilligan, Ryan Patrick; Smith, Phillip James; Jakupca, Ian Joseph; Bennett, William Raymond; Guzik, Monica Christine; Fincannon, Homer J.

    2017-01-01

    The Advanced Exploration Systems (AES) Advanced Modular Power Systems (AMPS) Project is investigating different power systems for various lunar and Martian mission concepts. The AMPS Fuel Cell (FC) team has created two system-level models to evaluate the performance of regenerative fuel cell (RFC) systems employing different fuel cell chemistries. Proton Exchange Membrane fuel cells PEMFCs contain a polymer electrolyte membrane that separates the hydrogen and oxygen cavities and conducts hydrogen cations (protons) across the cell. Solid Oxide fuel cells (SOFCs) operate at high temperatures, using a zirconia-based solid ceramic electrolyte to conduct oxygen anions across the cell. The purpose of the modeling effort is to down select one fuel cell chemistry for a more detailed design effort. Figures of merit include the system mass, volume, round trip efficiency, and electrolyzer charge power required. PEMFCs operate at around 60 degrees Celsius versus SOFCs which operate at temperatures greater than 700 degrees Celsius. Due to the drastically different operating temperatures of the two chemistries the thermal control systems (TCS) differ. The PEM TCS is less complex and is characterized by a single pump cooling loop that uses deionized water coolant and rejects heat generated by the system to the environment via a radiator. The solid oxide TCS has its own unique challenges including the requirement to reject high quality heat and to condense the steam produced in the reaction. This paper discusses the modeling of thermal control systems for an extraterrestrial RFC that utilizes either a PEM or solid oxide fuel cell.

  20. Passive seismic experiment - A summary of current status. [Apollo-initiated lunar surface station data

    Science.gov (United States)

    Latham, G. V.; Dorman, H. J.; Horvath, P.; Ibrahim, A. K.; Koyama, J.; Nakamura, Y.

    1978-01-01

    The data set obtained from the four-station Apollo seismic network including signals from approximately 11,800 events, is surveyed. Some refinement of the lunar model will result, but its gross features remain the same. Attention is given to the question of a small, molten lunar core, the answer to which remains dependent on analysis of signals from a far side impact. Seventy three sources of repeating, deep moonquakes have been identified, thirty nine of which have been accurately located. Concentrated at depths from 800 to 1000 km, the periodicities of these events have led to the hypothesis that they are generated by tidal stresses. Lunar seismic data has also indicated that the meteoroid population is ten times lower than originally determined from earth based observations. Lunar seismic activity is much lower and mountainous masses show no sign of sinking, in contrast to earth, as a result of the lunar crust being four times thicker. While much work remains to be done, significant correlation between terrestrial and lunar observations can be seen.

  1. Lunar Circular Structure Classification from Chang 'e 2 High Resolution Lunar Images with Convolutional Neural Network

    Science.gov (United States)

    Zeng, X. G.; Liu, J. J.; Zuo, W.; Chen, W. L.; Liu, Y. X.

    2018-04-01

    Circular structures are widely distributed around the lunar surface. The most typical of them could be lunar impact crater, lunar dome, et.al. In this approach, we are trying to use the Convolutional Neural Network to classify the lunar circular structures from the lunar images.

  2. 100 kWe lunar/Mars surface power utilizing the SP-100 reactor with dynamic conversion

    International Nuclear Information System (INIS)

    Harty, R.B.; Mason, L.S.

    1992-01-01

    This paper reports on an integration study which was performed coupling an SP-100 reactor with either a Brayton of Stirling power conversion subsystem. a power level of 100 kWe was selected for the study. The power system was to be compatible with both the lunar and Mars surface environment and require no site preparation. In addition, the reactor was to have integral shielding and be completely self-contained, including its own auxiliary power for start-up. Initial reliability studies were performed to determine power conversion redundancy and engine module size. For the lunar environment, the reactor and primary coolant loop would be contained in a guard vessel to protect from a loss of primary loop containment. For the Mars environment, all refractory components including the reactor, primary coolant, and power conversion components would be contained in a vacuum vessel for protection against the CO 2 environment

  3. Lunar resource base

    Science.gov (United States)

    Pulley, John; Wise, Todd K.; Roy, Claude; Richter, Phil

    A lunar base that exploits local resources to enhance the productivity of a total SEI scenario is discussed. The goals were to emphasize lunar science and to land men on Mars in 2016 using significant amounts of lunar resources. It was assumed that propulsion was chemical and the surface power was non-nuclear. Three phases of the base build-up are outlined, the robotic emplacement of the first elements is detailed and a discussion of future options is included.

  4. Effects of Crystallinity, Composition, and Texture on Hydrogen Solubility and Adsorption in Lunar Surface Materials and their Relevance to Remote Sensing

    Science.gov (United States)

    Dyar, M. D.; Hibbitts, C.; Orlando, T. M.; Poston, M.; Grieves, G. A.

    2011-12-01

    . For example, OH region absorption coefficients for forsterite and clinopyroxene are 3× higher than those for feldspar and orthopyroxene [1] and orders of magnitude different from silicate glasses. Thus bands with equal areas from different materials (e.g. anorthite vs. olivine/pyroxene/glass in lunar highlands vs. maria) do not imply equal H concentrations, further complicating the task of deriving H concentrations from remote-sensed spectra of mixed phases. Also, crystalline materials on the lunar surface are extremely rough, with an effective spherical particle size of ~ 1 μm, which means that the reflectance spectra will be dominated by H from the exterior of the grains by providing more surface area for bonding of adsorbates than on smooth surfaces, also enhancing band depth due to optical scattering. [1] Rossman, G.R. (2006) Revs. Mineral. Geochem., 62, 1-28.

  5. Lunar CATALYST

    Data.gov (United States)

    National Aeronautics and Space Administration — Lunar Cargo Transportation and Landing by Soft Touchdown (Lunar CATALYST) is a NASA initiative to encourage the development of U.S. private-sector robotic lunar...

  6. Distribution and Origin of Amino Acids in Lunar Regolith Samples

    Science.gov (United States)

    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.

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

    Science.gov (United States)

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

    2011-01-01

    Understanding the composition of Mercury's crust is key to comprehending the formation of the planet. The regolith, derived from the crustal bedrock, has been altered via a set of space weathering processes. These processes are the same set of mechanisms that work to form Mercury's exosphere, and are moderated by the local space environment and the presence of an intrinsic planetary magnetic field. The alterations need to be understood in order to determine the initial crustal compositions. The complex interrelationships between Mercury's exospheric processes, the space environment, and surface composition are examined and reviewed. The processes are examined in the context of our understanding of these same processes on the lunar and asteroid regoliths. Keywords: Mercury (planet) Space weathering Surface processes Exosphere Surface composition Space environment 3

  8. Surface and bulk MHD instabilities due to insulator coating imperfections

    International Nuclear Information System (INIS)

    Xu Zengyu; Reed, C.B.; Pan Chuanjie

    2002-01-01

    Experiments were performed using copper electrodes inserted into the wall of a perfectly insulated duct to simulate insulator coating flaking or cracking. The results show that surface electric potential U and MHD pressure drop ΔP exhibit a non-monotonic behavior with increasing V 0 , while the magnetic field B 0 is held constant. Additional experiments were also performed keeping all external experimental conditions fixed while measuring the change of U, V 0 , B 0 , and ΔP with increasing time. It was found that while all external experimental conditions were kept constant, the system changed by itself and U, V 0 and ΔP exhibited a non-monotonic behavior with increasing time. The results seem contrary to the law of ΔP∝V 0 B 0 n , but are consistent with conservation of energy, which implies that the change is due to some inherent feature of the system, or possibly instabilities, which may occur due to insulator coating imperfections

  9. Solar Wind Implantation into Lunar Regolith II: Monte Carlo Simulations of Hydrogen Retention in a Surface with Defects and the Hydrogen (H, H2) Exosphere

    Science.gov (United States)

    Tucker, O. J.; Farrell, W. M.; Killen, R. M.; Hurley, D. M.

    2018-01-01

    Recently, the near-infrared observations of the OH veneer on the lunar surface by the Moon Mineralogy Mapper (M3) have been refined to constrain the OH content to 500-750 parts per million (ppm). The observations indicate diurnal variations in OH up to 200 ppm possibly linked to warmer surface temperatures at low latitude. We examine the M3 observations using a statistical mechanics approach to model the diffusion of implanted H in the lunar regolith. We present results from Monte Carlo simulations of the diffusion of implanted solar wind H atoms and the subsequently derived H and H2 exospheres.

  10. Lunar Map Catalog

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Map Catalog includes various maps of the moon's surface, including Apollo landing sites; earthside, farside, and polar charts; photography index maps; zone...

  11. Lunar electrostatic effects and protection

    International Nuclear Information System (INIS)

    Sun, Yongwei; Yuan, Qingyun; Xiong, Jiuliang

    2013-01-01

    The space environment and features on the moon surface are factors in strong electrostatic electrification. Static electricity will be produced in upon friction between lunar soil and detectors or astronauts on the lunar surface. Lunar electrostatic environment effects from lunar exploration equipment are very harmful. Lunar dust with electrostatic charge may enter the equipment or even cover the instruments. It can affect the normal performance of moon detectors. Owing to the huge environmental differences between the moon and the earth, the electrostatic protection technology on the earth can not be applied. In this paper, we review the electrostatic characteristics of lunar dust, its effects on aerospace equipment and moon static elimination technologies. It was concluded that the effect of charged lunar dust on detectors and astronauts should be completely researched as soon as possible.

  12. Experimental Investigation of Space Radiation Processing in Lunar Soil Ilmenite: Combining Perspectives from Surface Science and Transmission Electron Microscopy

    Science.gov (United States)

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

    2010-01-01

    Energetic ions mostly from the solar wind play a major role in lunar space weathering because they contribute structural and chemical changes to the space-exposed surfaces of lunar regolith grains. In mature mare soils, ilmenite (FeTiO3) grains in the finest size fraction have been shown in transmission electron microscope (TEM) studies to exhibit key differences in their response to space radiation processing relative to silicates [1,2,3]. In ilmenite, solar ion radiation alters host grain outer margins to produce 10-100 nm thick layers that are microstructurally complex, but dominantly crystalline compared to the amorphous radiation-processed rims on silicates [1,2,3]. Spatially well-resolved analytical TEM measurements also show nm-scale compositional and chemical state changes in these layers [1,3]. These include shifts in Fe/Ti ratio from strong surface Fe-enrichment (Fe/Ti >> 1), to Fe depletion (Fe/Ti < 1) at 40-50 nm below the grain surface [1,3]. These compositional changes are not observed in the radiation-processed rims on silicates [4]. Several mechanism(s) to explain the overall relations in the ilmenite grain rims by radiation processing and/or additional space weathering processes were proposed by [1], and remain under current consideration [3]. A key issue has concerned the ability of ion radiation processing alone to produce some of the deeper- penetrating compositional changes. In order to provide some experimental constraints on these questions, we have performed a combined X-ray photoelectron spectroscopy (XPS) and field-emission scanning transmission electron (FE-STEM) study of experimentally ion-irradiated ilmenite. A key feature of this work is the combination of analytical techniques sensitive to changes in the irradiated samples at depth scales going from the immediate surface (approx.5 nm; XPS), to deeper in the grain interior (5-100 nm; FE-STEM).

  13. Lunar surface engineering properties experiment definition. Volume 2: Mechanics of rolling sphere-soil slope interaction

    Science.gov (United States)

    Hovland, H. J.; Mitchell, J. K.

    1971-01-01

    The soil deformation mode under the action of a rolling sphere (boulder) was determined, and a theory based on actual soil failure mechanism was developed which provides a remote reconnaissance technique for study of soil conditions using boulder track observations. The failure mechanism was investigated by using models and by testing an instrumented spherical wheel. The wheel was specifically designed to measure contact pressure, but it also provided information on the failure mechanism. Further tests included rolling some 200 spheres down sand slopes. Films were taken of the rolling spheres, and the tracks were measured. Implications of the results and reevaluation of the lunar boulder tracks are discussed.

  14. Lunar Surface Scenarios: Habitation and Life Support Systems for a Pressurized Rover

    Science.gov (United States)

    Anderson, Molly; Hanford, Anthony; Howard, Robert; Toups, Larry

    2006-01-01

    Pressurized rovers will be a critical component of successful lunar exploration to enable safe investigation of sites distant from the outpost location. A pressurized rover is a complex system with the same functions as any other crewed vehicle. Designs for a pressurized rover need to take into account significant constraints, a multitude of tasks to be performed inside and out, and the complexity of life support systems to support the crew. In future studies, pressurized rovers should be given the same level of consideration as any other vehicle occupied by the crew.

  15. View of the Lunar Module 'Orion' and Lunar Roving Vehicle during first EVA

    Science.gov (United States)

    1972-01-01

    A view of the Lunar Module (LM) 'Orion' and Lunar Roving Vehicle (LRV), as photographed by Astronaut Charles M. Duke Jr., lunar module pilot, during the first Apollo 16 extravehicular activity (EVA-1) at the Descates landing site. Astronaut John W. Young, commander, can be seen directly behind the LRV. The lunar surface feature in the left background is Stone Mountain.

  16. Effects of illumination differences on photometric stereo shape-and-albedo-from-shading for precision lunar surface reconstruction

    Science.gov (United States)

    Chung Liu, Wai; Wu, Bo; Wöhler, Christian

    2018-02-01

    Photoclinometric surface reconstruction techniques such as Shape-from-Shading (SfS) and Shape-and-Albedo-from-Shading (SAfS) retrieve topographic information of a surface on the basis of the reflectance information embedded in the image intensity of each pixel. SfS or SAfS techniques have been utilized to generate pixel-resolution digital elevation models (DEMs) of the Moon and other planetary bodies. Photometric stereo SAfS analyzes images under multiple illumination conditions to improve the robustness of reconstruction. In this case, the directional difference in illumination between the images is likely to affect the quality of the reconstruction result. In this study, we quantitatively investigate the effects of illumination differences on photometric stereo SAfS. Firstly, an algorithm for photometric stereo SAfS is developed, and then, an error model is derived to analyze the relationships between the azimuthal and zenith angles of illumination of the images and the reconstruction qualities. The developed algorithm and error model were verified with high-resolution images collected by the Narrow Angle Camera (NAC) of the Lunar Reconnaissance Orbiter Camera (LROC). Experimental analyses reveal that (1) the resulting error in photometric stereo SAfS depends on both the azimuthal and the zenith angles of illumination as well as the general intensity of the images and (2) the predictions from the proposed error model are consistent with the actual slope errors obtained by photometric stereo SAfS using the LROC NAC images. The proposed error model enriches the theory of photometric stereo SAfS and is of significance for optimized lunar surface reconstruction based on SAfS techniques.

  17. The Lunar Dust Environment

    Science.gov (United States)

    Szalay, Jamey Robert

    Planetary bodies throughout the solar system are continually bombarded by dust particles, largely originating from cometary activities and asteroidal collisions. Surfaces of bodies with thick atmospheres, such as Venus, Earth, Mars and Titan are mostly protected from incoming dust impacts as these particles ablate in their atmospheres as 'shooting stars'. However, the majority of bodies in the solar system have no appreciable atmosphere and their surfaces are directly exposed to the flux of high speed dust grains. Impacts onto solid surfaces in space generate charged and neutral gas clouds, as well as solid secondary ejecta dust particles. Gravitationally bound ejecta clouds forming dust exospheres were recognized by in situ dust instruments around the icy moons of Jupiter and Saturn, and had not yet been observed near bodies with refractory regolith surfaces before NASA's Lunar Dust and Environment Explorer (LADEE) mission. In this thesis, we first present the measurements taken by the Lunar Dust Explorer (LDEX), aboard LADEE, which discovered a permanently present, asymmetric dust cloud surrounding the Moon. The global characteristics of the lunar dust cloud are discussed as a function of a variety of variables such as altitude, solar longitude, local time, and lunar phase. These results are compared with models for lunar dust cloud generation. Second, we present an analysis of the groupings of impacts measured by LDEX, which represent detections of dense ejecta plumes above the lunar surface. These measurements are put in the context of understanding the response of the lunar surface to meteoroid bombardment and how to use other airless bodies in the solar system as detectors for their local meteoroid environment. Third, we present the first in-situ dust measurements taken over the lunar sunrise terminator. Having found no excess of small grains in this region, we discuss its implications for the putative population of electrostatically lofted dust.

  18. Lunar neutron source function

    International Nuclear Information System (INIS)

    Kornblum, J.J.

    1974-01-01

    The search for a quantitative neutron source function for the lunar surface region is justified because it contributes to our understanding of the history of the lunar surface and of nuclear process occurring on the moon since its formation. A knowledge of the neutron source function and neutron flux distribution is important for the interpretation of many experimental measurements. This dissertation uses the available pertinent experimental measurements together with theoretical calculations to obtain an estimate of the lunar neutron source function below 15 MeV. Based upon reasonable assumptions a lunar neutron source function having adjustable parameters is assumed for neutrons below 15 MeV. The lunar neutron source function is composed of several components resulting from the action of cosmic rays with lunar material. A comparison with previous neutron calculations is made and significant differences are discussed. Application of the results to the problem of lunar soil histories is examined using the statistical model for soil development proposed by Fireman. The conclusion is drawn that the moon is losing mass

  19. Lunar transportation system

    Science.gov (United States)

    1993-07-01

    The University Space Research Association (USRA) requested the University of Minnesota Spacecraft Design Team to design a lunar transportation infrastructure. This task was a year long design effort culminating in a complete conceptual design and presentation at Johnson Space Center. The mission objective of the design group was to design a system of vehicles to bring a habitation module, cargo, and crew to the lunar surface from LEO and return either or both crew and cargo safely to LEO while emphasizing component commonality, reusability, and cost effectiveness. During the course of the design, the lunar transportation system (LTS) has taken on many forms. The final design of the system is composed of two vehicles, a lunar transfer vehicle (LTV) and a lunar excursion vehicle (LEV). The LTV serves as an efficient orbital transfer vehicle between the earth and the moon while the LEV carries crew and cargo to the lunar surface. Presented in the report are the mission analysis, systems layout, orbital mechanics, propulsion systems, structural and thermal analysis, and crew systems, avionics, and power systems for this lunar transportation concept.

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

    Science.gov (United States)

    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

  1. Lunar remote sensing and measurements

    Science.gov (United States)

    Moore, H.J.; Boyce, J.M.; Schaber, G.G.; Scott, D.H.

    1980-01-01

    , and the lunar dipole field was revised to no more than 6x 10 19 gauss. High-resolution mapping of fields of weak remanent magnetism (to 0.1 gamma) was made possible by the Apollo plasma and energetic-particle experiment. Although the causes of remanent magnetism are poorly understood, correlations with geologic units suggest the results may ultimately have farreaching significance to lunar history. Maria are much less structured by strong surface magnetic anomalies than the highlands. The strongest anomalies are associated with ejecta of farside basins, plains materials filling pre-Imbrian craters, and other old Imbrian to pre-Imbrian units. The high remanent fields could be due to cooling of ejecta units in an ancient magnetic field, lunar regolith maturity, extensive reworking and disruption of a magnetized layer, or simply surface roughness. Orbital geochemical experiments have shown that lunar high lands have larger Al: Si ratios and smaller Mg: Si ratios than maria. These two ratios are inversely related on a regional basis. With the exception of fresh craters, albedo and Al : Si ratios vary directly, showing that compositional differences as well as exposure of fresh materials are responsible for high albedos. Statistically treated data show that geologic contacts and compositional boundaries are concentric and can be roughly matched. Some craters on mare material have penetrated the mare fill, bringing highland-type materials to the surface. Natural radioactivity from thorium, potassium, and uranium is inversely correlated with elevation. Mare regions are enriched in iron, titanium, and magnesium relative to the highlands. Orbital bistatic-radar results provide estimates of surface roughness at two scale lengths (about 30 m and 250 m), which agree with visual estimates of roughness. The dielectric constant of the lunar surface, where sampled, is uniform to 13-cm radar and near 3. Slope frequency distributions measured by the radar vary and

  2. Lunar Polar Cold Traps: Spatial Distribution and Temperatures

    Science.gov (United States)

    Paige, David A.; Siegler, M.; Lawrence, D. J.

    2006-09-01

    We have developed a ray-tracing and radiosity model that can accurately calculate lunar surface and subsurface temperatures for arbitrary topography. Using available digital elevation models for the lunar north and south polar regions derived from Clementine laser altimeter and image data, as well as ground-based radar data, we have calculated lunar surface and subsurface temperatures at 2 km resolution that include full effects of indirect solar and infrared radiation due to topography. We compare our thermal model results with maps of epithermal neutron flux measured by Lunar Prospector. When we use the ray tracing and thermal model to account for the effects of temperature and topography on the neutron measurements, our results show that the majority of the moon's polar cold traps are not filled with water ice.

  3. Lunar near-surface shear wave velocities at the Apollo landing sites as inferred from spectral amplitude ratios

    Science.gov (United States)

    Horvath, P.; Latham, G. V.; Nakamura, Y.; Dorman, H. J.

    1980-01-01

    The horizontal-to-vertical amplitude ratios of the long-period seismograms are reexamined to determine the shear wave velocity distributions at the Apollo 12, 14, 15, and 16 lunar landing sites. Average spectral ratios, computed from a number of impact signals, were compared with spectral ratios calculated for the fundamental mode Rayleigh waves in media consisting of homogeneous, isotropic, horizontal layers. The shear velocities of the best fitting models at the different sites resemble each other and differ from the average for all sites by not more than 20% except for the bottom layer at station 14. The shear velocities increase from 40 m/s at the surface to about 400 m/s at depths between 95 and 160 m at the various sites. Within this depth range the velocity-depth functions are well represented by two piecewise linear segments, although the presence of first-order discontinuities cannot be ruled out.

  4. Enhancement of surface magnetism due to bulk bond dilution

    International Nuclear Information System (INIS)

    Tsallis, C.; Sarmento, E.F.; Albuquerque, E.L. de

    1985-01-01

    Within a renormalization group scheme, the phase diagram of a semi-infinite simple cubic Ising ferromagnet is discussed, with arbitrary surface and bulk coupling constants, and including possible dilution of the bulk bonds. It is obtained that dilution makes easier the appearance of surface magnetism in the absence of bulk magnetism. (Author) [pt

  5. Investigations of surface characterization of silicone rubber due to ...

    Indian Academy of Sciences (India)

    Unknown

    †Department of Polymer Technology, Crescent Engineering College, Chennai 600 048, India. Abstract. In the present work, tracking ... Silicone rubber; surface degradation; tracking; WAXD; TG–DTA. 1. Introduction. Power transmission at ... mena in polymer insulators under d.c. voltages. Hence the tracking phenomena ...

  6. Trapped surfaces due to concentration of gravitational radiation

    International Nuclear Information System (INIS)

    Beig, R.; O Murchadha, N.

    1991-01-01

    Sequences of global, asympotically flat solutions to the time-symmetric initial value constraints of general relativity in vacuo are constructed which develop outer trapped surfaces for large values of the argument. Thus all such configurations must gravitationally collapse. A new proof of the positivity of mass in the strong-field regime is also found. (Authors) 22 refs

  7. Bacterial Cell Surface Damage Due to Centrifugal Compaction

    NARCIS (Netherlands)

    Peterson, Brandon W.; Sharma, Prashant K.; van der Mei, Henny C.; Busscher, Henk J.

    Centrifugal damage has been known to alter bacterial cell surface properties and interior structures, including DNA. Very few studies exist on bacterial damage caused by centrifugation because of the difficulty in relating centrifugation speed and container geometry to the damage caused. Here, we

  8. Petrology of lunar rocks and implication to lunar evolution

    Science.gov (United States)

    Ridley, W. I.

    1976-01-01

    Recent advances in lunar petrology, based on studies of lunar rock samples available through the Apollo program, are reviewed. Samples of bedrock from both maria and terra have been collected where micrometeorite impact penetrated the regolith and brought bedrock to the surface, but no in situ cores have been taken. Lunar petrogenesis and lunar thermal history supported by studies of the rock sample are discussed and a tentative evolutionary scenario is constructed. Mare basalts, terra assemblages of breccias, soils, rocks, and regolith are subjected to elemental analysis, mineralogical analysis, trace content analysis, with studies of texture, ages and isotopic composition. Probable sources of mare basalts are indicated.

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

    International Nuclear Information System (INIS)

    Meyer, Fred W.; Harris, Peter R.; Taylor, C.N.; Meyer, Harry M. III; Barghouty, N.; Adams, J. Jr.

    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 higher 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.

  10. Development of surface relief on polycrystalline metals due to sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Voitsenya, V.S. [IPP NSC KIPT, 61108 Kharkov (Ukraine); Balden, M. [Max-Planck-Institut für Plasmaphysik, EURATOM Association, Garching (Germany); Bardamid, A.F. [Taras Shevchenko National University, 01033 Kiev (Ukraine); Bondarenko, V.N. [IPP NSC KIPT, 61108 Kharkov (Ukraine); Davis, J.W., E-mail: jwdavis@starfire.utias.utoronto.ca [University of Toronto Institute for Aerospace Studies, 4925 Dufferin St., Toronto, ON, Canada M3H5T6 (Canada); Konovalov, V.G.; Ryzhkov, I.V.; Skoryk, O.O.; Solodovchenko, S.I. [IPP NSC KIPT, 61108 Kharkov (Ukraine); Zhang-jian, Zhou [University of Science and Technology Beijing, Beijing 100 083 (China)

    2013-05-01

    The characteristics of surface microrelief that appear in sputtering experiments with polycrystalline metals of various grain sizes have been studied. Specimens with grain sizes varying from 30–70 nm in the case of crystallized amorphous alloys, to 1–3 μm for technical tungsten grade and 10–100 μm for recrystallized tungsten were investigated. A model is proposed for the development of roughness on polycrystalline metals which is based on the dependence of sputtering rate on crystal orientation. The results of the modeling are in good agreement with experiments showing that the length scale of roughness is much larger than the grain size.

  11. Air Stripping Designs and Reactive Water Purification Processes for the Lunar Surface

    Science.gov (United States)

    Boul, Peter J.; Lange, Kevin; Conger, Bruce; Anderson, Molly

    2010-01-01

    Air stripping designs are considered to reduce the presence of volatile organic compounds in the purified water. Components of the wastewater streams are ranked by Henry's Law Constant and the suitability of air stripping in the purification of wastewater in terms of component removal is evaluated. Distillation processes are modeled in tandem with air stripping to demonstrate the potential effectiveness and utility of these methods in recycling wastewater on the Moon. Scaling factors for distillation and air stripping columns are presented to account for the difference in the lunar gravitation environment. Commercially available distillation and air stripping units which are considered suitable for Exploration Life Support are presented. The advantages to the various designs are summarized with respect to water purity levels, power consumption, and processing rates. An evaluation of reactive distillation and air stripping is presented with regards to the reduction of volatile organic compounds in the contaminated water and air. Among the methods presented, an architecture is presented for the evaluation of the simultaneous oxidation of organics in air and water. These and other designs are presented in light of potential improvements in power consumptions and air and water purities for architectures which include catalytic activity integrated into the water processor. In particular, catalytic oxidation of organics may be useful as a tool to remove contaminants that more traditional distillation and/or air stripping columns may not remove. A review of the current leading edge at the commercial level and at the research frontier in catalytically active materials is presented. Themes and directions from the engineering developments in catalyst design are presented conceptually in light of developments in the nanoscale chemistry of a variety of catalyst materials.

  12. Rover exploration on the lunar surface; a science proposal for SELENE-B mission

    Science.gov (United States)

    Sasaki, S.; Kubota, T.; Akiyama, H.; Hirata, N.; Kunii, Y.; Matsumoto, K.; Okada, T.; Otake, M.; Saiki, K.; Sugihara, T.

    LUNARSURFACE:ASCIENCES. Sasaki (1), T. Kubota (2) , H. Akiyama (1) , N. Hirata (3), Y. Kunii (4), K. Matsumoto (5), T. Okada (2), M. Otake (3), K. Saiki (6), T. Sugihara (3) (1) Department of Earth and Planetary Science, Univ. Tokyo, (2) Institute of Space and Astronautical Sciences, (3) National Space Development Agency of Japan, (4) Department of Electrical and Electronic Engineering, Chuo Univ., (5) National Aerospace Laboratory of Japan, (6) Research Institute of Materials and Resources, Akita Univ. sho@eps.s.u -tokyo.ac.jp/Fax:+81-3-5841-4569 A new lunar landing mission (SELENE-B) is now in consideration in Japan. Scientific investigation plans using a rover are proposed. To clarify the origin and evolution of the moon, the early crustal formation and later mare volcanic processes are still unveiled. We proposed two geological investigation plans: exploration of a crater central peak to discover subsurface materials and exploration of dome-cone structures on young mare region. We propose multi-band macro/micro camera using AOTF, X-ray spectrometer/diffractometer and gamma ray spectrometer. Since observation of rock fragments in brecciaed rocks is necessary, the rover should have cutting or scraping mechanism of rocks. In our current scenario, landing should be performed about 500m from the main target (foot of a crater central peak or a cone/dome). After the spectral survey by multi-band camera on the lander, the rover should be deployed for geological investigation. The rover should make a short (a few tens meter) round trip at first, then it should perform traverse observation toward the main target. Some technological investigations on SELENE-B project will be also presented.

  13. Lunar horticulture.

    Science.gov (United States)

    Walkinshaw, C. H.

    1971-01-01

    Discussion of the role that lunar horticulture may fulfill in helping establish the life support system of an earth-independent lunar colony. Such a system is expected to be a hybrid between systems which depend on lunar horticulture and those which depend upon the chemical reclamation of metabolic waste and its resynthesis into nutrients and water. The feasibility of this approach has been established at several laboratories. Plants grow well under reduced pressures and with oxygen concentrations of less than 1% of the total pressure. The carbon dioxide collected from the lunar base personnel should provide sufficient gas pressure (approx. 100 mm Hg) for growing the plants.

  14. Laser-powered lunar base

    International Nuclear Information System (INIS)

    Costen, R.; Humes, D.H.; Walker, G.H.; Williams, M.D.; Deyoung, R.J.

    1989-01-01

    The objective was to compare a nuclear reactor-driven Sterling engine lunar base power source to a laser-to-electric converter with orbiting laser power station, each providing 1 MW of electricity to the lunar base. The comparison was made on the basis of total mass required in low-Earth-orbit for each system. This total mass includes transportation mass required to place systems in low-lunar orbit or on the lunar surface. The nuclear reactor with Sterling engines is considered the reference mission for lunar base power and is described first. The details of the laser-to-electric converter and mass are discussed. The next two solar-driven high-power laser concepts, the diode array laser or the iodine laser system, are discussed with associated masses in low-lunar-orbit. Finally, the payoff for laser-power beaming is summarized

  15. Development of Additive Construction Technologies for Application to Development of Lunar/Martian Surface Structures Using In-Situ Materials

    Science.gov (United States)

    Werkheiser, Niki J.; Fiske, Michael R.; Edmunson, Jennifer E.; Khoshnevis, Berokh

    2015-01-01

    For long-duration missions on other planetary bodies, the use of in situ materials will become increasingly critical. As human presence on these bodies expands, so must the breadth of the structures required to accommodate them including habitats, laboratories, berms, radiation shielding for natural radiation and surface reactors, garages, solar storm shelters, greenhouses, etc. Planetary surface structure manufacturing and assembly technologies that incorporate in situ resources provide options for autonomous, affordable, pre-positioned environments with radiation shielding features and protection from micrometeorites, exhaust plume debris, and other hazards. The ability to use in-situ materials to construct these structures will provide a benefit in the reduction of up-mass that would otherwise make long-term Moon or Mars structures cost prohibitive. The ability to fabricate structures in situ brings with it the ability to repair these structures, which allows for the self-sufficiency and sustainability necessary for long-duration habitation. Previously, under the auspices of the MSFC In-Situ Fabrication and Repair (ISFR) project and more recently, under the jointly-managed MSFC/KSC Additive Construction with Mobile Emplacement (ACME) project, the MSFC Surface Structures Group has been developing materials and construction technologies to support future planetary habitats with in-situ resources. One such additive construction technology is known as Contour Crafting. This paper presents the results to date of these efforts, including development of novel nozzle concepts for advanced layer deposition using this process. Conceived initially for rapid development of cementitious structures on Earth, it also lends itself exceptionally well to the automated fabrication of planetary surface structures using minimally processed regolith as aggregate, and binders developed from in situ materials as well. This process has been used successfully in the fabrication of

  16. Impact on surface water quality due to coke oven effluents

    International Nuclear Information System (INIS)

    Ghose, M.K.; Roy, S.

    1994-01-01

    Large quantities of water are used for the quenching of hot coke and also for washing the gas produced from the coke ovens. Liquid effluents thus generated are highly polluted and are being discharged into the river Damodar without proper treatment. Four coke plants of Bharat Coking Coal Ltd.(BCCL) have been surveyed for characterization and to assess the impact on surface water quality. About 175-200 kilolitres of waste water is being generated per day by each of the coke plants. The concentration of CO, BOD, COD, TSS, phenol and cyanide in each of the coke plants were found to exceed the limits specified by pollution control board. Ammonia, oil and grease and TDS were found to be 19.33 mg/l, 7.81 mg/l, 1027.75 mg/l respectively. Types of samples collected, sampling frequencies, sample preservation and the results obtained have been discussed. (author). 6 refs., 1 tab., 1 fig

  17. Basic radio interferometry for future lunar missions

    NARCIS (Netherlands)

    Aminaei, Amin; Klein Wolt, Marc; Chen, Linjie; Bronzwaer, Thomas; Pourshaghaghi, Hamid Reza; Bentum, Marinus Jan; Falcke, Heino

    2014-01-01

    In light of presently considered lunar missions, we investigate the feasibility of the basic radio interferometry (RIF) for lunar missions. We discuss the deployment of two-element radio interferometer on the Moon surface. With the first antenna element is envisaged to be placed on the lunar lander,

  18. Lunar remnant magnetic field mapping from orbital observations of mirrored electrons

    Energy Technology Data Exchange (ETDEWEB)

    McCoy, J E [National Aeronautics and Space Administration, Houston, Tex. (USA). Johnson Space Center; Anderson, K A; Lin, R P; Howe, H C; McGuire, R E [California Univ., Berkeley (USA). Space Sciences Lab.

    1975-09-01

    Areas of lunar surface magnetic field are observed to ''mirror'' low energy electrons present in the normal lunar space environment. The ambient electrons provide, in effect, a probe along the ambient magnetic field lines down to the lunar surface for remote sensing of the presence of surface fields. Use of the on-board vector magnetometer measurements of the ambient magnetic field orientation allows accurate projection of such mapping onto the lunar surface. Preliminary maps of the lunar surface magnetic areas underlying the orbit of the ''Particles and Fields Satellite deployed from Apollo 16'' have been generated, obtaining 40% coverage from partial data to demonstrate feasibility of the technique. These maps reveal many previously unreported areas of surface magnetism. The method is sensitive to fields of less than 0.1..gamma.. at the surface. The surface field regions observed are generally due to sources smaller than 10-50km in size, although many individual regions are often so close together as to give much larger regions of effectively continuous mirroring. Absence of consistent mirroring by any global field places an upper limit on the size of any net lunar dipole moment of less than 10/sup 10/..gamma..km/sup 3/. Much additional information regarding the magnetic regions can be obtained by correlated analysis of both the electron return and vector magnetometer measurements at orbital altitude, the two techniques providing each other with directly complimentary measurements at the satellite and along the ambient field lines to the surface.

  19. Lunar cement

    Science.gov (United States)

    Agosto, William N.

    1992-01-01

    With the exception of water, the major oxide constituents of terrestrial cements are present at all nine lunar sites from which samples have been returned. However, with the exception of relatively rare cristobalite, the lunar oxides are not present as individual phases but are combined in silicates and in mixed oxides. Lime (CaO) is most abundant on the Moon in the plagioclase (CaAl2Si2O8) of highland anorthosites. It may be possible to enrich the lime content of anorthite to levels like those of Portland cement by pyrolyzing it with lunar-derived phosphate. The phosphate consumed in such a reaction can be regenerated by reacting the phosphorus product with lunar augite pyroxenes at elevated temperatures. Other possible sources of lunar phosphate and other oxides are discussed.

  20. Smart Multifunction Antenna for Lunar/Planetary Surface Network, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA is planning a series of human and robotic missions to explore the Moon and later Mars. According to NASA SBIR topic O1.10, surface networks are needed for these...

  1. Composition of lunar noble gases traped 2.5 AE and 3.5 AE ago

    International Nuclear Information System (INIS)

    Eugster, O.

    1986-01-01

    The times when the soils 74001 and 73261 were exposed on the lunar surface were determined by the U-235 - Xe-136 dating method. The isotopic composition of the trapped noble gases in these two soils is compared with that of the surface correlated noble gases in the young soils 12001 and in the present day solar wind. The surface correlated trapped gases are a mixture of implanted solar wind particles and retrapped lunar atmospheric gases. The observed changes are interpreted as a result of decreasing outgassing of radiogenic Ar-40 and perhaps He-4 and of fissiogenic Xe from the lunar crust. The old soils probably also contain surface correlated Kr-80 and Kr-82 produced by secondary cosmic ray neutron capture of adsorbed or retrapped bromine. To some extent the isotopic composition of the trapped gases in old lunar soil may also have been altered due to diffusion loss from material of low retentivity

  2. A new moonquake catalog from Apollo 17 seismic data I: Lunar Seismic Profiling Experiment: Thermal moonquakes and implications for surface processes

    Science.gov (United States)

    Weber, R. C.; Dimech, J. L.; Phillips, D.; Molaro, J.; Schmerr, N. C.

    2017-12-01

    Apollo 17's Lunar Seismic Profiling Experiment's (LSPE) primary objective was to constrain the near-surface velocity structure at the landing site using active sources detected by a 100 m-wide triangular geophone array. The experiment was later operated in "listening mode," and early studies of these data revealed the presence of thermal moonquakes - short-duration seismic events associated with terminator crossings. However, the full data set has never been systematically analyzed for natural seismic signal content. In this study, we analyze 8 months of continuous LSPE data using an automated event detection technique that has previously successfully been applied to the Apollo 16 Passive Seismic Experiment data. We detected 50,000 thermal moonquakes from three distinct event templates, representing impulsive, intermediate, and emergent onset of seismic energy, which we interpret as reflecting their relative distance from the array. Impulsive events occur largely at sunrise, possibly representing the thermal "pinging" of the nearby lunar lander, while emergent events occur at sunset, possibly representing cracking or slumping in more distant surface rocks and regolith. Preliminary application of an iterative event location algorithm to a subset of the impulsive waveforms supports this interpretation. We also perform 3D modeling of the lunar surface to explore the relative contribution of the lander, known rocks and surrounding topography to the thermal state of the regolith in the vicinity of the Apollo 17 landing site over the course of the lunar diurnal cycle. Further development of both this model and the event location algorithm may permit definitive discrimination between different types of local diurnal events e.g. lander noise, thermally-induced rock breakdown, or fault creep on the nearby Lee-Lincoln scarp. These results could place important constraints on both the contribution of seismicity to regolith production, and the age of young lobate scarps.

  3. Man-Made Debris In and From Lunar Orbit

    Science.gov (United States)

    Johnson, Nicholas L.; McKay, Gordon A. (Technical Monitor)

    1999-01-01

    During 1966-1976, as part of the first phase of lunar exploration, 29 manned and robotic missions placed more than 40 objects into lunar orbit. Whereas several vehicles later successfully landed on the Moon and/or returned to Earth, others were either abandoned in orbit or intentionally sent to their destruction on the lunar surface. The former now constitute a small population of lunar orbital debris; the latter, including four Lunar Orbiters and four Lunar Module ascent stages, have contributed to nearly 50 lunar sites of man's refuse. Other lunar satellites are known or suspected of having fallen from orbit. Unlike Earth satellite orbital decays and deorbits, lunar satellites impact the lunar surface unscathed by atmospheric burning or melting. Fragmentations of lunar satellites, which would produce clouds of numerous orbital debris, have not yet been detected. The return to lunar orbit in the 1990's by the Hagoromo, Hiten, Clementine, and Lunar Prospector spacecraft and plans for increased lunar exploration early in the 21st century, raise questions of how best to minimize and to dispose of lunar orbital debris. Some of the lessons learned from more than 40 years of Earth orbit exploitation can be applied to the lunar orbital environment. For the near-term, perhaps the most important of these is postmission passivation. Unique solutions, e.g., lunar equatorial dumps, may also prove attractive. However, as with Earth satellites, debris mitigation measures are most effectively adopted early in the concept and design phase, and prevention is less costly than remediation.

  4. Pulmonary and Systemic Immune Response to Chronic Lunar Dust Inhalation

    Science.gov (United States)

    Crucian, Brian; Quiriarte, Heather; Nelman, Mayra; Lam, Chiu-wing; James, John T.; Sams, Clarence

    2014-01-01

    Background: Due to millennia of meteorite impact with virtually no erosive effects, the surface of the Moon is covered by a layer of ultra-fine, reactive Lunar dust. Very little is known regarding the toxicity of Lunar dust on human physiology. Given the size and electrostatic characteristics of Lunar dust, countermeasures to ensure non-exposure of astronauts will be difficult. To ensure astronaut safety during any future prolonged Lunar missions, it is necessary to establish the effect of chronic pulmonary Lunar dust exposure on all physiological systems. Methods: This study assessed the toxicity of airborne lunar dust exposure in rats on pulmonary and system immune system parameters. Rats were exposed to 0, 20.8, or 60.8 mg/m3 of lunar dust (6h/d; 5d/wk) for up to 13 weeks. Sacrifices occurred after exposure durations of 1day, 7 days, 4 weeks and 13 weeks post-exposure, when both blood and lung lavage fluid were collected for analysis. Lavage and blood assays included leukocyte distribution by flow cytometry, electron/fluorescent microscopy, and cytokine concentration. Cytokine production profiles following mitogenic stimulation were performed on whole blood only. Results: Untreated lavage fluid was comprised primarily of pulmonary macrophages. Lunar dust inhalation resulted in an influx of neutrophils and lymphocytes. Although the percentage of lymphocytes increased, the T cell CD4:CD8 ratio was unchanged. Cytokine analysis of the lavage fluid showed increased levels of IL-1b and TNFa. These alterations generally persisted through the 13 week sampling. Blood analysis showed few systemic effects from the lunar dust inhalation. By week 4, the peripheral granulocyte percentage was elevated in the treated rats. Plasma cytokine levels were unchanged in all treated rats compared to controls. Peripheral blood analysis showed an increased granulocyte percentage and altered cytokine production profiles consisting of increased in IL-1b and IL-6, and decreased IL-2

  5. M3 spectral analysis of lunar swirls and the link between optical maturation and surface hydroxyl formation at magnetic anomalies

    Science.gov (United States)

    Kramer, G.Y.; Besse, S.; Dhingra, D.; Nettles, J.; Klima, R.; Garrick-Bethell, I.; Clark, Roger N.; Combe, J.-P.; Head, J. W.; Taylor, L.A.; Pieters, C.M.; Boardman, J.; McCord, T.B.

    2011-01-01

    We examined the lunar swirls using data from the Moon Mineralogy Mapper (M3). The improved spectral and spatial resolution of M3 over previous spectral imaging data facilitates distinction of subtle spectral differences, and provides new information about the nature of these enigmatic features. We characterized spectral features of the swirls, interswirl regions (dark lanes), and surrounding terrain for each of three focus regions: Reiner Gamma, Gerasimovich, and Mare Ingenii. We used Principle Component Analysis to identify spectrally distinct surfaces at each focus region, and characterize the spectral features that distinguish them. We compared spectra from small, recent impact craters with the mature soils into which they penetrated to examine differences in maturation trends on- and off-swirl. Fresh, on-swirl crater spectra are higher albedo, exhibit a wider range in albedos and have well-preserved mafic absorption features compared with fresh off-swirl craters. Albedoand mafic absorptions are still evident in undisturbed, on-swirl surface soils, suggesting the maturation process is retarded. The spectral continuum is more concave compared with off-swirl spectra; a result of the limited spectral reddening being mostly constrained to wavelengths less than ∼1500 nm. Off-swirl spectra show very little reddening or change in continuum shape across the entire M3 spectral range. Off-swirl spectra are dark, have attenuated absorption features, and the narrow range in off-swirl albedos suggests off-swirl regions mature rapidly. Spectral parameter maps depicting the relative OH surface abundance for each of our three swirl focus regions were created using the depth of the hydroxyl absorption feature at 2.82 μm. For each of the studied regions, the 2.82 μm absorption feature is significantly weaker on-swirl than off-swirl, indicating the swirls are depleted in OH relative to their surroundings. The spectral characteristics of the swirls and adjacent terrains

  6. Global silicate mineralogy of the Moon from the Diviner lunar radiometer.

    Science.gov (United States)

    Greenhagen, Benjamin T; Lucey, Paul G; Wyatt, Michael B; Glotch, Timothy D; Allen, Carlton C; Arnold, Jessica A; Bandfield, Joshua L; Bowles, Neil E; Donaldson Hanna, Kerri L; Hayne, Paul O; Song, Eugenie; Thomas, Ian R; Paige, David A

    2010-09-17

    We obtained direct global measurements of the lunar surface using multispectral thermal emission mapping with the Lunar Reconnaissance Orbiter Diviner Lunar Radiometer Experiment. Most lunar terrains have spectral signatures that are consistent with known lunar anorthosite and basalt compositions. However, the data have also revealed the presence of highly evolved, silica-rich lunar soils in kilometer-scale and larger exposures, expanded the compositional range of the anorthosites that dominate the lunar crust, and shown that pristine lunar mantle is not exposed at the lunar surface at the kilometer scale. Together, these observations provide compelling evidence that the Moon is a complex body that has experienced a diverse set of igneous processes.

  7. Integration of Apollo Lunar Sample Data into Google Moon

    Science.gov (United States)

    Dawson, Melissa D.; Todd, Nancy S.; Lofgren, Gary

    2010-01-01

    The Google Moon Apollo Lunar Sample Data Integration project is a continuation of the Apollo 15 Google Moon Add-On project, which provides a scientific and educational tool for the study of the Moon and its geologic features. The main goal of this project is to provide a user-friendly interface for an interactive and educational outreach and learning tool for the Apollo missions. Specifically, this project?s focus is the dissemination of information about the lunar samples collected during the Apollo missions by providing any additional information needed to enhance the Apollo mission data on Google Moon. Apollo missions 15 and 16 were chosen to be completed first due to the availability of digitized lunar sample photographs and the amount of media associated with these missions. The user will be able to learn about the lunar samples collected in these Apollo missions, as well as see videos, pictures, and 360 degree panoramas of the lunar surface depicting the lunar samples in their natural state, following collection and during processing at NASA. Once completed, these interactive data layers will be submitted for inclusion into the Apollo 15 and 16 missions on Google Moon.

  8. Mineralogical and chemical properties of the lunar regolith

    Science.gov (United States)

    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.

  9. Lunar Plants

    Data.gov (United States)

    National Aeronautics and Space Administration — We present an open design for a first plant growth module on the Moon (LPX). The primary science goal of lunar habitat is to investigate germination and initial...

  10. Lunar Flashlight

    Data.gov (United States)

    National Aeronautics and Space Administration — Lunar Flashlight (LF) is an innovative cubesat mission sponsored by NASA’s Advanced Exploration Systems (AES) division to be launched on the Space Launch System...

  11. The MELiSSA GreenMOSS Study: Preliminary Design Considerations for a Greenhouse Module on the Lunar Surface

    Science.gov (United States)

    Lobascio, Cesare; Paille, Christel; Lamantea, Matteo Maria; Boscheri, Giorgio; Rossetti, Vittorio

    Extended human presence on an extraterrestrial planetary surface will be made possible by the development of life support systems affordable in the long term. The key elements to support the goal will be the maximization of closure of air and water cycles, as well as the development of cost-effective and reliable hardware, including a careful strategic effort toward reduction of spare parts and consumables. Regenerative life support systems likely represent the final step toward long term sustainability of a space crew, allowing in situ food production and regeneration of organic waste. Referring to the MELiSSA loop, a key element for food production is the Higher Plant Compartment. The paper focuses on the preliminary design of a Greenhouse at the lunar South Pole, as performed within the “Greenhouse Module for Space System” (GreenMOSS) study, under a contract from the European Space Agency. The greenhouse is in support to a relatively small crew for provision of an energetic food complement. Resources necessary for the greenhouse such as water, carbon dioxide and nitrogen are assumed available, as required. The relevant mass and energy balances for incoming resources should be part of future studies, and should help integrate this element with the interfacing MELISSA compartments. Net oxygen production and harvested crop biomass from the greenhouse system will be quantified. This work presents the results of the two major trade-offs performed as part of this study: artificial vs natural illumination and monocrop vs multicrop solutions. Comparisons among possible design solutions were driven by the ALiSSE metric as far as practicable within this preliminary stage, considering mass and power parameters. Finally, the paper presents the mission duration threshold for determining the convenience of the designed solution with respect to other resources provision strategies

  12. The search for Ar in the lunar atmosphere using the Lunar Reconnaissance Orbiter's LAMP instrument.

    Science.gov (United States)

    Cook, J. C.; Stern, S. A.; Feldman, P. D.; Gladstone, R.; Retherford, K. D.; Greathouse, T. K.; Grava, C.

    2014-12-01

    The Apollo 17 mass spectrometer, LACE, first measured mass 40 particles in the lunar atmosphere, and over a nine-month period, detected variations correlated with the lunar day (Hoffman et al., 1973, LPSC, 4, 2865). LACE detected a high particle density at dusk (0.6-1.0x104 cm-3), decreasing through the lunar night to a few hundred cm-3, then increasing rapidly before dawn to levels 2-4 times greater than at dusk. No daytime measurements were made due to instrument saturation. Given the LACE measurements' periodic nature, and the Ar abundance in lunar regolith samples (Kaiser, 1972, EPSL, 13, 387), it was concluded that mass 40 was likely due to Ar. Benna et al. (2014, LPSC, 45, 1535) recently reported that the Neutral Mass Spectrometer (NMS) aboard LADEE also detected Ar (mass 40) with similar diurnal profiles. We report on UV spectra of the lunar atmosphere as obtained by the Lunar Reconnaissance Orbiter (LRO). Aboard LRO is the UV-spectrograph, LAMP (Lyman Alpha Mapping Project), spanning the spectral range 575 to 1965 Å. LAMP is typically oriented toward the surface and has been mapping the Moon since September 2009. LAMP also observes the tenuous lunar atmosphere when the surface is in darkness, but the atmospheric column below LRO is illuminated. We have previously used nadir oriented twilight observations to examine the sparse lunar atmosphere (Feldman et al., 2012, Icarus, 221, 854; Cook et al., 2013, Icarus, 225, 681; Stern et al., 2013, Icarus, 226, 1210; Cook & Stern 2014, Icarus, 236, 48). In Cook et al., 2013, we reported an upper limit for Ar of 2.3x104 cm-3. Since then, we have collected additional data and refined our search method by focusing on the regions (near equator) and local times (dawn and dusk) where Ar has been reported previously. We have carefully considered effective area calibration and g-factor accuracies and find these to be unlikely explanations for the order of magnitude differences. We will report new results, which provide much

  13. Modification of Roberts' Theory for Rocket Exhaust Plumes Eroding Lunar Soil

    Science.gov (United States)

    Metzger, Philip T.; Lane, John E.; Immer, Christopher D.

    2008-01-01

    Roberts' model of lunar soil erosion beneath a landing rocket has been updated in several ways to predict the effects of future lunar landings. The model predicts, among other things, the number of divots that would result on surrounding hardware due to the impact of high velocity particulates, the amount and depth of surface material removed, the volume of ejected soil, its velocity, and the distance the particles travel on the Moon. The results are compared against measured results from the Apollo program and predictions are made for mitigating the spray around a future lunar outpost.

  14. Potassium Rankine cycle power conversion systems for lunar-Mars surface power

    International Nuclear Information System (INIS)

    Holcomb, R.S.

    1992-01-01

    The potassium Rankine cycle has good potential for application to nuclear power systems for surface power on the moon and Mars. A substantial effort on the development of the power conversion system was carried out in the 1960's which demonstrated successful operation of components made of stainless steel at moderate temperatures. This technology could be applied in the near term to produce a 360 kW(e) power system by coupling a stainless steel power conversion system to the SP-100 reactor. Improved performance could be realized in later systems by utilizing niobium or tantalum refractory metal alloys in the reactor and power conversion system. The design characteristics and estimated mass of power systems for each of three technology levels are presented in the paper

  15. Lunar Regolith Particle Shape Analysis

    Science.gov (United States)

    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.

  16. Simulation of the «COSMONAUT-ROBOT» System Interaction on the Lunar Surface Based on Methods of Machine Vision and Computer Graphics

    Science.gov (United States)

    Kryuchkov, B. I.; Usov, V. M.; Chertopolokhov, V. A.; Ronzhin, A. L.; Karpov, A. A.

    2017-05-01

    Extravehicular activity (EVA) on the lunar surface, necessary for the future exploration of the Moon, involves extensive use of robots. One of the factors of safe EVA is a proper interaction between cosmonauts and robots in extreme environments. This requires a simple and natural man-machine interface, e.g. multimodal contactless interface based on recognition of gestures and cosmonaut's poses. When travelling in the "Follow Me" mode (master/slave), a robot uses onboard tools for tracking cosmonaut's position and movements, and on the basis of these data builds its itinerary. The interaction in the system "cosmonaut-robot" on the lunar surface is significantly different from that on the Earth surface. For example, a man, dressed in a space suit, has limited fine motor skills. In addition, EVA is quite tiring for the cosmonauts, and a tired human being less accurately performs movements and often makes mistakes. All this leads to new requirements for the convenient use of the man-machine interface designed for EVA. To improve the reliability and stability of human-robot communication it is necessary to provide options for duplicating commands at the task stages and gesture recognition. New tools and techniques for space missions must be examined at the first stage of works in laboratory conditions, and then in field tests (proof tests at the site of application). The article analyzes the methods of detection and tracking of movements and gesture recognition of the cosmonaut during EVA, which can be used for the design of human-machine interface. A scenario for testing these methods by constructing a virtual environment simulating EVA on the lunar surface is proposed. Simulation involves environment visualization and modeling of the use of the "vision" of the robot to track a moving cosmonaut dressed in a spacesuit.

  17. Quantifying the changes of soil surface microroughness due to rainfall impact on a smooth surface

    Directory of Open Access Journals (Sweden)

    B. K. B. Abban

    2017-09-01

    Full Text Available This study examines the rainfall-induced change in soil microroughness of a bare smooth soil surface in an agricultural field. The majority of soil microroughness studies have focused on surface roughness on the order of ∼ 5–50 mm and have reported a decay of soil surface roughness with rainfall. However, there is quantitative evidence from a few studies suggesting that surfaces with microroughness less than 5 mm may undergo an increase in roughness when subject to rainfall action. The focus herein is on initial microroughness length scales on the order of 2 mm, a low roughness condition observed seasonally in some landscapes under bare conditions and chosen to systematically examine the increasing roughness phenomenon. Three rainfall intensities of 30, 60, and 75 mm h−1 are applied to a smoothened bed surface in a field plot via a rainfall simulator. Soil surface microroughness is recorded via a surface-profile laser scanner. Several indices are utilized to quantify the soil surface microroughness, namely the random roughness (RR index, the crossover length, the variance scale from the Markov–Gaussian model, and the limiting difference. Findings show a consistent increase in roughness under the action of rainfall, with an overall agreement between all indices in terms of trend and magnitude. Although this study is limited to a narrow range of rainfall and soil conditions, the results suggest that the outcome of the interaction between rainfall and a soil surface can be different for smooth and rough surfaces and thus warrant the need for a better understanding of this interaction.

  18. Endogenous Lunar Volatiles

    Science.gov (United States)

    McCubbin, F. M.; Liu, Y.; Barnes, J. J.; Boyce, J. W.; Day, J. M. D.; Elardo, S. M.; Hui, H.; Magna, T.; Ni, P.; Tartese, R.; hide

    2017-01-01

    The chapter will begin with an introduction that defines magmatic volatiles (e.g., H, F, Cl, S) versus geochemical volatiles (e.g., K, Rb, Zn). We will discuss our approach of understanding both types of volatiles in lunar samples and lay the ground work for how we will determine the overall volatile budget of the Moon. We will then discuss the importance of endogenous volatiles in shaping the "Newer Views of the Moon", specifically how endogenous volatiles feed forward into processes such as the origin of the Moon, magmatic differentiation, volcanism, and secondary processes during surface and crustal interactions. After the introduction, we will include a re-view/synthesis on the current state of 1) apatite compositions (volatile abundances and isotopic compositions); 2) nominally anhydrous mineral phases (moderately to highly volatile); 3) volatile (moderately to highly volatile) abundances in and isotopic compositions of lunar pyroclastic glass beads; 4) volatile (moderately to highly volatile) abundances in and isotopic compositions of lunar basalts; 5) volatile (moderately to highly volatile) abundances in and isotopic compositions of melt inclusions; and finally 6) experimental constraints on mineral-melt partitioning of moderately to highly volatile elements under lunar conditions. We anticipate that each section will summarize results since 2007 and focus on new results published since the 2015 Am Min review paper on lunar volatiles [9]. The next section will discuss how to use sample abundances of volatiles to understand the source region and potential caveats in estimating source abundances of volatiles. The following section will include our best estimates of volatile abundances and isotopic compositions (where permitted by available data) for each volatile element of interest in a number of important lunar reservoirs, including the crust, mantle, KREEP, and bulk Moon. The final section of the chapter will focus upon future work, outstanding questions

  19. Lunar magma transport phenomena

    Science.gov (United States)

    Spera, Frank J.

    1992-01-01

    An outline of magma transport theory relevant to the evolution of a possible Lunar Magma Ocean and the origin and transport history of the later phase of mare basaltic volcanism is presented. A simple model is proposed to evaluate the extent of fractionation as magma traverses the cold lunar lithosphere. If Apollo green glasses are primitive and have not undergone significant fractionation en route to the surface, then mean ascent rates of 10 m/s and cracks of widths greater than 40 m are indicated. Lunar tephra and vesiculated basalts suggest that a volatile component plays a role in eruption dynamics. The predominant vapor species appear to be CO CO2, and COS. Near the lunar surface, the vapor fraction expands enormously and vapor internal energy is converted to mixture kinetic energy with the concomitant high-speed ejection of vapor and pyroclasts to form lunary fire fountain deposits such as the Apollo 17 orange and black glasses and Apollo 15 green glass.

  20. Sodium Atoms in the Lunar Exotail: Observed Velocity and Spatial Distributions

    Science.gov (United States)

    Line, Michael R.; Mierkiewicz, E. J.; Oliversen, R. J.; Wilson, J. K.; Haffner, L. M.; Roesler, F. L.

    2011-01-01

    The lunar sodium tail extends long distances due to radiation pressure on sodium atoms in the lunar exosphere. Our earlier observations determined the average radial velocity of sodium atoms moving down the lunar tail beyond Earth along the Sun-Moon-Earth line (i.e., the anti-lunar point) to be 12.4 km/s. Here we use the Wisconsin H-alpha Mapper to obtain the first kinematically resolved maps of the intensity and velocity distribution of this emission over a 15 x times 15 deg region on the sky near the anti-lunar point. We present both spatially and spectrally resolved observations obtained over four nights around new moon in October 2007. The spatial distribution of the sodium atoms is elongated along the ecliptic with the location of the peak intensity drifting 3 degrees east along the ecliptic per night. Preliminary modeling results suggest that the spatial and velocity distributions in the sodium exotail are sensitive to the near surface lunar sodium velocity distribution and that observations of this sort along with detailed modeling offer new opportunities to describe the time history of lunar surface sputtering over several days.

  1. NASA Lunar Base Wireless System Propagation Analysis

    Science.gov (United States)

    Hwu, Shian U.; Upanavage, Matthew; Sham, Catherine C.

    2007-01-01

    There have been many radio wave propagation studies using both experimental and theoretical techniques over the recent years. However, most of studies have been in support of commercial cellular phone wireless applications. The signal frequencies are mostly at the commercial cellular and Personal Communications Service bands. The antenna configurations are mostly one on a high tower and one near the ground to simulate communications between a cellular base station and a mobile unit. There are great interests in wireless communication and sensor systems for NASA lunar missions because of the emerging importance of establishing permanent lunar human exploration bases. Because of the specific lunar terrain geometries and RF frequencies of interest to the NASA missions, much of the published literature for the commercial cellular and PCS bands of 900 and 1800 MHz may not be directly applicable to the lunar base wireless system and environment. There are various communication and sensor configurations required to support all elements of a lunar base. For example, the communications between astronauts, between astronauts and the lunar vehicles, between lunar vehicles and satellites on the lunar orbits. There are also various wireless sensor systems among scientific, experimental sensors and data collection ground stations. This presentation illustrates the propagation analysis of the lunar wireless communication and sensor systems taking into account the three dimensional terrain multipath effects. It is observed that the propagation characteristics are significantly affected by the presence of the lunar terrain. The obtained results indicate the lunar surface material, terrain geometry and antenna location are the important factors affecting the propagation characteristics of the lunar wireless systems. The path loss can be much more severe than the free space propagation and is greatly affected by the antenna height, surface material and operating frequency. The

  2. The enigma of lunar magnetism

    Science.gov (United States)

    Hood, L. L.

    1981-01-01

    Current understandings of the nature and probable origin of lunar magnetism are surveyed. Results of examinations of returned lunar samples are discussed which reveal the main carrier of the observed natural remanent magnetization to be iron, occasionally alloyed with nickel and cobalt, but do not distinguish between thermoremanent and shock remanent origins, and surface magnetometer data is presented, which indicates small-scale magnetic fields with a wide range of field intensities implying localized, near-surface sources. A detailed examination is presented of orbital magnetometer and charged particle data concerning the geologic nature and origin of magnetic anomaly sources and the directional properties of the magnetization, which exhibit a random distribution except for a depletion in the north-south direction. A lunar magnetization survey with global coverage provided by a polar orbiting satellite is suggested as a means of placing stronger constraints on the origin of lunar crustal magnetization.

  3. Lunar Topography: Results from the Lunar Orbiter Laser Altimeter

    Science.gov (United States)

    Neumann, Gregory; Smith, David E.; Zuber, Maria T.; Mazarico, Erwan

    2012-01-01

    The Lunar Orbiter Laser Altimeter (LOLA) onboard the Lunar Reconnaissance Orbiter (LRO) has been operating nearly continuously since July 2009, accumulating over 6 billion measurements from more than 2 billion in-orbit laser shots. LRO's near-polar orbit results in very high data density in the immediate vicinity of the lunar poles, with full coverage at the equator from more than 12000 orbital tracks averaging less than 1 km in spacing at the equator. LRO has obtained a global geodetic model of the lunar topography with 50-meter horizontal and 1-m radial accuracy in a lunar center-of-mass coordinate system, with profiles of topography at 20-m horizontal resolution, and 0.1-m vertical precision. LOLA also provides measurements of reflectivity and surface roughness down to its 5-m laser spot size. With these data LOLA has measured the shape of all lunar craters 20 km and larger. In the proposed extended mission commencing late in 2012, LOLA will concentrate observations in the Southern Hemisphere, improving the density of the polar coverage to nearly 10-m pixel resolution and accuracy to better than 20 m total position error. Uses for these data include mission planning and targeting, illumination studies, geodetic control of images, as well as lunar geology and geophysics. Further improvements in geodetic accuracy are anticipated from the use of re ned gravity fields after the successful completion of the Gravity Recovery and Interior Laboratory (GRAIL) mission in 2012.

  4. Prospective Ukrainian lunar orbiter mission

    Science.gov (United States)

    Shkuratov, Y.; Litvinenko, L.; Shulga, V.; Yatskiv, Y.; Kislyuk, V.

    Ukraine has launch vehicles that are able to deliver about 300 kg to the lunar orbit. Future Ukrainian lunar program may propose a polar orbiter. This orbiter should fill principal information gaps in our knowledge about the Moon after Clementine and Lunar Prospector missions and the future missions, like Smart-1, Lunar-A, and Selene. We consider that this can be provided by radar studies of the Moon with supporting optical polarimetric observations from lunar polar orbit. These experiments allow one to better understand global structure of the lunar surface in a wide range of scales, from microns to kilometers. We propose three instruments for the prospective lunar orbiter. They are: a synthetic aperture imaging radar (SAR), ground-penetrating radar (GPR), and imaging polarimeter (IP). The main purpose of SAR is to study with high resolution (50 m) the permanently shadowed sites in the lunar polar regions. These sites are cold traps for volatiles, and have a potential of resource utilization. Possible presence of water ice in the regolith in the sites makes them interesting for permanent manned bases on the Moon. Radar imaging and mapping of other interesting regions could be also planned. Multi-frequencies multi-polarization soun d ing of the lunar surface with GPR can provide information about internal structure of the lunar surface from meters to several hundred meters deep. GPR can be used for measuring the megaregolith layer properties, detection of cryptomaria, and studies of internal structure of the largest craters. IP will be a CCD camera with an additional suite of polarizers. Modest spatial resolution (100 m) should provide a total coverage or a large portion of the lunar surface in oblique viewing basically at large phase angles. Polarization degree at large (>90°) phase angles bears information about characteristic size of the regolith particles. Additional radiophysical experiments are considered with the use of the SAR system, e.g., bistatic radar

  5. Magmatic intrusions in the lunar crust

    Science.gov (United States)

    Michaut, C.; Thorey, C.

    2015-10-01

    The lunar highlands are very old, with ages covering a timespan between 4.5 to 4.2 Gyr, and probably formed by flotation of light plagioclase minerals on top of the lunar magma ocean. The lunar crust provides thus an invaluable evidence of the geological and magmatic processes occurring in the first times of the terrestrial planets history. According to the last estimates from the GRAIL mission, the lunar primary crust is particularly light and relatively thick [1] This low-density crust acted as a barrier for the dense primary mantle melts. This is particularly evident in the fact that subsequent mare basalts erupted primarily within large impact basin: at least part of the crust must have been removed for the magma to reach the surface. However, the trajectory of the magma from the mantle to the surface is unknown. Using a model of magma emplacement below an elastic overlying layer with a flexural wavelength Λ, we characterize the surface deformations induced by the presence of shallow magmatic intrusions. We demonstrate that, depending on its size, the intrusion can show two different shapes: a bell shape when its radius is smaller than 4 times Λ or a flat top with small bended edges if its radius is larger than 4 times Λ[2]. These characteristic shapes for the intrusion result in characteristic deformations at the surface that also depend on the topography of the layer overlying the intrusion [3].Using this model we provide evidence of the presence of intrusions within the crust of the Moon as surface deformations in the form of low-slope lunar domes and floor-fractured craters. All these geological features have morphologies consistent with models of magma spreading at depth and deforming an overlying elastic layer. Further more,at floor-fractured craters, the deformation is contained within the crater interior, suggesting that the overpressure at the origin of magma ascent and intrusion was less than the pressure due to the weight of the crust removed by

  6. Dusty plasma in the region of the lunar terminator

    Energy Technology Data Exchange (ETDEWEB)

    Popel, S. I., E-mail: popel@iki.rssi.ru; Zelenyi, L. M. [Russian Academy of Sciences, Space Research Institute (Russian Federation); Atamaniuk, B. [Polish Academy of Sciences, Space Research Center (Poland)

    2016-05-15

    Dusty plasma in the region of the lunar terminator is considered. It is shown that, in this region, a structure resembling a plasma sheath forms near the lunar surface. This sheath creates a potential barrier, due to which electrons over the illuminated part of the Moon are confined by electrostatic forces. The width of the sheath-like structure is on the order of the ion Debye length. In this structure, significant (about several hundred V/m) electric fields arise, which lift charged micron-size dust grains to heights of several tens of centimeters. The suggested effect may be used to explain the glow observed by the Surveyor spacecraft over the lunar terminator.

  7. Isopleths of surface air concentration and surface air kerma rate due to a radioactive cloud released from a stack (3)

    International Nuclear Information System (INIS)

    Tachibana, Haruo; Kikuchi, Masamitsu; Sekita, Tsutomu; Yamaguchi, Takenori

    2004-06-01

    This report is a revised edition of 'Isopleths of Surface Air Concentration and Surface Air Absorbed Dose Rate due to a Radioactive Cloud Released from a Stack(II) '(JAERI-M 90-206) and based on the revised Nuclear Safety Guidelines reflected the ICRP1990 Recommendation. Characteristics of this report are the use of Air Karma Rate (Gy/h) instead of Air Absorbed Dose Rate (Gy/h), and the record of isopleths of surface air concentration and surface air karma rate on CD-ROM. These recorded data on CD-ROM can be printed out on paper and/or pasted on digital map by personal computer. (author)

  8. Ergodization of magnetic surfaces due to finite beta effect in a helical system

    International Nuclear Information System (INIS)

    Hayashi, Takaya.

    1989-04-01

    Breaking of magnetic surfaces due to finite beta effect in a l=2 heliotron/torsatron configuration is studied by using a newly developed three dimensional equilibrium code. Breaking can be suppressed by a larger aspect ratio configuration, shaping of magnetic surface (inward shift or prolate shape), pitch modulation of helical coils, or pressure profile control. (author)

  9. Quality factor due to roughness scattering of shear horizontal surface acoustic waves in nanoresonators

    NARCIS (Netherlands)

    Palasantzas, G.

    2008-01-01

    In this work we study the quality factor associated with dissipation due to scattering of shear horizontal surface acoustic waves by random self-affine roughness. It is shown that the quality factor is strongly influenced by both the surface roughness exponent H and the roughness amplitude w to

  10. Thermodynamics of lunar ilmenite reduction

    Science.gov (United States)

    Altenberg, B. H.; Franklin, H. A.; Jones, C. H.

    1993-01-01

    With the prospect of returning to the moon, the development of a lunar occupation would fulfill one of the goals of the Space Exploration Initiative (SEI) of the late 1980's. Processing lunar resources into useful products, such as liquid oxygen for fuel and life support, would be one of many aspects of an active lunar base. ilmenite (FeTiO3) is found on the lunar surface and can be used as a feed stock to produce oxygen. Understanding the various ilmenite-reduction reactions elucidates many processing options. Defining the thermodynamic chemical behavior at equilibrium under various conditions of temperature and pressures can be helpful in specifying optimal operating conditions. Differences between a previous theoretical analysis and experimentally determined results has sparked interest in trying to understand the effect of operating pressure on the hydrogen-reduction-of-ilmenite reaction. Various aspects of this reduction reaction are discussed.

  11. Design and Construction of Manned Lunar Base

    Science.gov (United States)

    Li, Zhijie

    2016-07-01

    Building manned lunar base is one of the core aims of human lunar exploration project, which is also an important way to carry out the exploitation and utilization of lunar in situ resources. The most important part of manned lunar base is the design and construction of living habitation and many factors should be considered including science objective and site selection. Through investigating and research, the scientific goals of manned lunar base should be status and characteristics ascertainment of lunar available in situ resources, then developing necessary scientific experiments and utilization of lunar in situ resources by using special environment conditions of lunar surface. The site selection strategy of manned lunar base should rely on scientific goals according to special lunar surface environment and engineering capacity constraints, meanwhile, consulting the landing sites of foreign unmanned and manned lunar exploration, and choosing different typical regions of lunar surface and analyzing the landform and physiognomy, reachability, thermal environment, sunlight condition, micro meteoroids protection and utilization of in situ resources, after these steps, a logical lunar living habitation site should be confirmed. This paper brings out and compares three kinds of configurations with fabricating processes of manned lunar base, including rigid module, flexible and construction module manned lunar base. 1.The rigid habitation module is usually made by metal materials. The design and fabrication may consult the experience of space station, hence with mature technique. Because this configuration cannot be folded or deployed, which not only afford limit working and living room for astronauts, but also needs repetitious cargo transit between earth and moon for lunar base extending. 2. The flexible module habitation can be folded in fairing while launching. When deploying on moon, the configuration can be inflatable or mechanically-deployed, which means under

  12. Charged-particle track analysis, thermoluminescence and microcratering studies of lunar samples

    International Nuclear Information System (INIS)

    Durrani, S.A.

    1977-01-01

    Studies of lunar samples (from both Apollo and Luna missions) have been carried out, using track analysis and thermoluminescence (t.l.) techniques, with a view to shedding light on the radiation and temperature histories of the Moon. In addition, microcraters in lunar glasses have been studied in order to elucidate the cosmic-dust impact history of the lunar regolith. In tracks studies, the topics discussed include the stabilizing effect of the thermal annealing of fossil tracks due to the lunar temperature cycle; the 'radiation annealing' of fresh heavy-ion tracks by large doses of protons (to simulate the effect of lunar radiation-damage on track registration); and correction factors for the anisotropic etching of crystals which are required in reconstructing the exposure history of lunar grains. An abundance ratio of ca. (1.1 + 0.3) x 10 -3 has been obtained, by the differential annealing technique, for the nuclei beyond the iron group to those within that group in the cosmic rays incident on the Moon. The natural t.l. of lunar samples has been used to estimate their effective storage temperature and mean depth below the surface. The results of the study of natural and artificially produced microcraters have been studied. (author)

  13. Lunar Core and Tides

    Science.gov (United States)

    Williams, J. G.; Boggs, D. H.; Ratcliff, J. T.

    2004-01-01

    Variations in rotation and orientation of the Moon are sensitive to solid-body tidal dissipation, dissipation due to relative motion at the fluid-core/solid-mantle boundary, and tidal Love number k2 [1,2]. There is weaker sensitivity to flattening of the core-mantle boundary (CMB) [2,3,4] and fluid core moment of inertia [1]. Accurate Lunar Laser Ranging (LLR) measurements of the distance from observatories on the Earth to four retroreflector arrays on the Moon are sensitive to lunar rotation and orientation variations and tidal displacements. Past solutions using the LLR data have given results for dissipation due to solid-body tides and fluid core [1] plus Love number [1-5]. Detection of CMB flattening, which in the past has been marginal but improving [3,4,5], now seems significant. Direct detection of the core moment has not yet been achieved.

  14. Feasibility of lunar Helium-3 mining

    Science.gov (United States)

    Kleinschneider, Andreas; Van Overstraeten, Dmitry; Van der Reijnst, Roy; Van Hoorn, Niels; Lamers, Marvin; Hubert, Laurent; Dijk, Bert; Blangé, Joey; Hogeveen, Joel; De Boer, Lennaert; Noomen, Ron

    With fossil fuels running out and global energy demand increasing, the need for alternative energy sources is apparent. Nuclear fusion using Helium-3 may be a solution. Helium-3 is a rare isotope on Earth, but it is abundant on the Moon. Throughout the space community lunar Helium-3 is often cited as a major reason to return to the Moon. Despite the potential of lunar Helium-3 mining, little research has been conducted on a full end-to-end mission. This abstract presents the results of a feasibility study conducted by students from Delft University of Technology. The goal of the study was to assess whether a continuous end-to-end mission to mine Helium-3 on the Moon and return it to Earth is a viable option for the future energy market. The set requirements for the representative end-to-end mission were to provide 10% of the global energy demand in the year 2040. The mission elements have been selected with multiple trade-offs among both conservative and novel concepts. A mission architecture with multiple decoupled elements for each transportation segment (LEO, transfer, lunar surface) was found to be the best option. It was found that the most critical element is the lunar mining operation itself. To supply 10% of the global energy demand in 2040, 200 tons of Helium-3 would be required per year. The resulting regolith mining rate would be 630 tons per second, based on an optimistic concentration of 20 ppb Helium-3 in lunar regolith. Between 1,700 to 2,000 Helium-3 mining vehicles would be required, if using University of Wisconsin’s Mark III miner. The required heating power, if mining both day and night, would add up to 39 GW. The resulting power system mass for the lunar operations would be in the order of 60,000 to 200,000 tons. A fleet of three lunar ascent/descent vehicles and 22 continuous-thrust vehicles for orbit transfer would be required. The costs of the mission elements have been spread out over expected lifetimes. The resulting profits from Helium

  15. INTERNAL STRUCTURE OF ASTEROIDS HAVING SURFACE SHEDDING DUE TO ROTATIONAL INSTABILITY

    Energy Technology Data Exchange (ETDEWEB)

    Hirabayashi, Masatoshi [Research Associate, Colorado Center for Astrodynamics Research, Aerospace Engineering Sciences, University of Colorado Boulder (United States); Sánchez, Diego Paul [Senior Research Associate, Colorado Center for Astrodynamics Research, Aerospace Engineering Sciences, University of Colorado Boulder (United States); Scheeres, Daniel J., E-mail: masatoshi.hirabayashi@colorado.edu [Richard Seebass Chair, Professor, Colorado Center for Astrodynamics Research, Aerospace Engineering Sciences, University of Colorado Boulder (United States)

    2015-07-20

    Surface shedding of an asteroid is a failure mode where surface materials fly off due to strong centrifugal forces beyond the critical spin period, while the internal structure does not deform significantly. This paper proposes a possible structure of an asteroid interior that leads to surface shedding due to rapid rotation rates. A rubble pile asteroid is modeled as a spheroid composed of a surface shell and a concentric internal core, the entire assembly called the test body. The test body is assumed to be uniformly rotating around a constant rotation axis. We also assume that while the bulk density and the friction angle are constant, the cohesion of the surface shell is different from that of the internal core. First, developing an analytical model based on limit analysis, we provide the upper and lower bounds for the actual surface shedding condition. Second, we use a Soft-sphere Discrete Element Method (SSDEM) to study dynamical deformation of the test body due to a quasi-static spin-up. In this paper we show the consistency of both approaches. Additionally, the SSDEM simulations show that the initial failure always occurs locally and not globally. In addition, as the core becomes larger, the size of lofted components becomes smaller. These results imply that if there is a strong core in a progenitor body, surface shedding is the most likely failure mode.

  16. INTERNAL STRUCTURE OF ASTEROIDS HAVING SURFACE SHEDDING DUE TO ROTATIONAL INSTABILITY

    International Nuclear Information System (INIS)

    Hirabayashi, Masatoshi; Sánchez, Diego Paul; Scheeres, Daniel J.

    2015-01-01

    Surface shedding of an asteroid is a failure mode where surface materials fly off due to strong centrifugal forces beyond the critical spin period, while the internal structure does not deform significantly. This paper proposes a possible structure of an asteroid interior that leads to surface shedding due to rapid rotation rates. A rubble pile asteroid is modeled as a spheroid composed of a surface shell and a concentric internal core, the entire assembly called the test body. The test body is assumed to be uniformly rotating around a constant rotation axis. We also assume that while the bulk density and the friction angle are constant, the cohesion of the surface shell is different from that of the internal core. First, developing an analytical model based on limit analysis, we provide the upper and lower bounds for the actual surface shedding condition. Second, we use a Soft-sphere Discrete Element Method (SSDEM) to study dynamical deformation of the test body due to a quasi-static spin-up. In this paper we show the consistency of both approaches. Additionally, the SSDEM simulations show that the initial failure always occurs locally and not globally. In addition, as the core becomes larger, the size of lofted components becomes smaller. These results imply that if there is a strong core in a progenitor body, surface shedding is the most likely failure mode

  17. Surface and Internal Waves due to a Moving Load on a Very Large Floating Structure

    Directory of Open Access Journals (Sweden)

    Taro Kakinuma

    2012-01-01

    Full Text Available Interaction of surface/internal water waves with a floating platform is discussed with nonlinearity of fluid motion and flexibility of oscillating structure. The set of governing equations based on a variational principle is applied to a one- or two-layer fluid interacting with a horizontally very large and elastic thin plate floating on the water surface. Calculation results of surface displacements are compared with the existing experimental data, where a tsunami, in terms of a solitary wave, propagates across one-layer water with a floating thin plate. We also simulate surface and internal waves due to a point load, such as an airplane, moving on a very large floating structure in shallow water. The wave height of the surface or internal mode is amplified when the velocity of moving point load is equal to the surface- or internal-mode celerity, respectively.

  18. Ancient Bombardment of the Inner Solar System: Reinvestigation of the "Fingerprints" of Different Impactor Populations on the Lunar Surface

    Science.gov (United States)

    Orgel, Csilla; Michael, Gregory; Fassett, Caleb I.; van der Bogert, Carolyn H.; Riedel, Christian; Kneissl, Thomas; Hiesinger, Harald

    2018-03-01

    The lunar cratering record provides valuable information about the late accretion history of the inner solar system. However, our understanding of the origin, rate, and timing of the impacting projectiles is far from complete. To learn more about these projectiles, we can examine crater size-frequency distributions (CSFDs) on the Moon. Here we reinvestigate the crater populations of 30 lunar basins (≥ 300 km) using the buffered nonsparseness correction technique, which takes crater obliteration into account, thus providing more accurate measurements for the frequencies of smaller crater sizes. Moreover, we revisit the stratigraphic relationships of basins based on N(20) crater frequencies, absolute model ages, and observation data. The buffered nonsparseness correction-corrected CSFDs of individual basins, particularly at smaller crater diameters are shifted upward. Contrary to previous studies, the shapes of the summed CSFDs of Pre-Nectarian (excluding South Pole-Aitken Basin), Nectarian (including Nectaris), and Imbrian (including Imbrium) basins show no statistically significant differences and thus provide no evidence for a change of impactor population.

  19. Lunar nitrogen: Secular variation or mixing?

    International Nuclear Information System (INIS)

    Norris, S.J.; Wright, I.P.; Pillinger, C.T.

    1986-01-01

    The two current models to explain the nearly 40% variation of the lunar nitrogen isotopic composition are: (1) secular variation of solar wind nitrogen; and (2) a two component mixing model having a constant, heavy solar wind admixed with varying amounts of indigenous light lunar N (LLN). Both models are needed to explain the step pyrolysis extraction profile. The secular variation model proposes that the low temperature release is modern day solar wind implanted into grain surfaces, the 900 C to 1100 C release is from grain surfaces which were once exposed to the ancient solar wind but which are now trapped inside agglutinates, and the >1100 C release as spallogenic N produced by cosmic rays. The mixing model ascribes the components to solar wind, indigenous lunar N and spallogenic N respectively. An extension of either interpretation is that the light N seen in lunar breccias or deep drill cores represent conditions when more N-14 was available to the lunar surface

  20. Lunar domes properties and formation processes

    CERN Document Server

    Lena, Raffaello; Phillips, Jim; Chiocchetta, Maria Teresa

    2013-01-01

    Lunar domes are structures of volcanic origin which are usually difficult to observe due to their low heights. The Lunar Domes Handbook is a reference work on these elusive features. It provides a collection of images for a large number of lunar domes, including telescopic images acquired with advanced but still moderately intricate amateur equipment as well as recent orbital spacecraft images. Different methods for determining the morphometric properties of lunar domes (diameter, height, flank slope, edifice volume) from image data or orbital topographic data are discussed. Additionally, multispectral and hyperspectral image data are examined, providing insights into the composition of the dome material. Several classification schemes for lunar domes are described, including an approach based on the determined morphometric quantities and spectral analyses. Furthermore, the book provides a description of geophysical models of lunar domes, which yield information about the properties of the lava from which the...

  1. Design of guidance laws for lunar pinpoint soft landing

    NARCIS (Netherlands)

    Guo, J.; Han, C.

    2009-01-01

    Future lunar missions ask for the capability to perform precise Guidance, Navigation and Control (GNC) to the selected landing sites on the lunar surface. This paper studies the guidance issues for the lunar pinpoint soft landing problem. The primary contribution of this paper is the design of

  2. Surface changes of poly-L-lactic acid due to annealing

    Science.gov (United States)

    Juřík, P.; Michaljaničová, I.; Slepička, P.; Kolskáa, Z.; Švorčík, V.

    2017-11-01

    Surface modifications are very important part of both current cutting-edge research and modern manufacturing. Our research is focused on poly-L-lactic acid, which is biocompatible and biodegradable polymer that offers applications in modern medicine. We observed morphological changes of the surface of metalized samples due to annealing and studied effect of modifications on total surface area and pore surface and volume. We observed that annealing of non-metalized samples had most pronounced effect up to the 70°C, after which all observed parameters dropped significantly. Metallization has changed behaviour of the samples significantly and resulted in generally lower surface area and porosity when compared to non-metalized samples.

  3. A new type of surface acoustic waves in solids due to nonlinear elasticity

    International Nuclear Information System (INIS)

    Mozhaev, V.G.

    1988-12-01

    It is shown that in nonlinear elastic semi-infinite medium possessing a property of self focusing of shear waves, besides bulk non-linear shear waves, new surface acoustic waves exist, localization of which near the boundary is entirely due to nonlinear effects. (author). 8 refs

  4. Surface potential at a ferroelectric grain due to asymmetric screening of depolarization fields

    Energy Technology Data Exchange (ETDEWEB)

    Genenko, Yuri A., E-mail: genenko@mm.tu-darmstadt.de; Hirsch, Ofer [Technische Universität Darmstadt, Darmstadt (Germany); Erhart, Paul [Chalmers University of Technology, Gothenburg (Sweden)

    2014-03-14

    Nonlinear screening of electric depolarization fields, generated by a stripe domain structure in a ferroelectric grain of a polycrystalline material, is studied within a semiconductor model of ferroelectrics. It is shown that the maximum strength of local depolarization fields is rather determined by the electronic band gap than by the spontaneous polarization magnitude. Furthermore, field screening due to electronic band bending and due to presence of intrinsic defects leads to asymmetric space charge regions near the grain boundary, which produce an effective dipole layer at the surface of the grain. This results in the formation of a potential difference between the grain surface and its interior of the order of 1 V, which can be of either sign depending on defect transition levels and concentrations. Exemplary acceptor doping of BaTiO{sub 3} is shown to allow tuning of the said surface potential in the region between 0.1 and 1.3 V.

  5. Dust particles investigation for future Russian lunar missions.

    Science.gov (United States)

    Dolnikov, Gennady; Horanyi, Mihaly; Esposito, Francesca; Zakharov, Alexander; Popel, Sergey; Afonin, Valeri; Borisov, Nikolay; Seran, Elena; Godefroy, Michel; Shashkova, Inna; Kuznetsov, Ilya; Lyash, Andrey; Vorobyova, Elena; Petrov, Oleg; Lisin, Evgeny

    emission. Dust analyzer instrument PmL for future Russian lender missons intends for investigation the dynamics of dusty plasma near lunar surface. PmL consist of three blocks: Impact Sensor and two Electric Field Sensors. Dust Experiment goals are: 1) Impact sensor to investigate the dynamics of dust particles near the lunar surface (speed, charge, mass, vectors of a fluxes) a) high speed micrometeorites b) secondary particles after micrometeorites soil bombardment c) levitating dust particles due to electrostatic fields PmL instrument will measure dust particle impulses. In laboratory tests we used - min impulse so as 7•10-11 N•c, by SiO2 dust particles, 20-40 µm with velocity about 0,5 -2,5 m/c, dispersion 0.3, and - max impulse was 10-6 N•c with possibility increased it by particles Pb-Sn 0,7 mm with velocity 1 m/c, dispersion ±0.3. Also Impact Sensor will measure the charge of dust particle as far as 10-15 C ( 1000 electrons). In case the charge and impulse of a dust particle are measured we can obtain velocity and mass of them. 2) Electric field Sensor will measure the value and dynamics of the electric fields the lunar surface. Two Electric Field Sensors both are measured the concentration and temperature of charged particles (electrons, ions, dust particles). Uncertainty of measurements is 10%. Electric Field Sensors contain of Lengmure probe. Using Lengmure probe to dark and light Moon surface we can obtain the energy spectra photoelectrons in different period of time. PmL instrument is developing, working out and manufacturing in IKI. Simultaneously with the PmL dust instrument to study lunar dust it would be very important to use an onboard TV system adjusted for imaging physical properties of dust on the lunar surface (adhesion, albedo, porosity, etc), and to collect dust particles samples from the lunar surface to return these samples to the Earth for measure a number of physic-chemical properties of the lunar dust, e.g. a quantum yield of

  6. Anomalous surface behavior of hydrated guanidinium ions due to ion pairing

    Science.gov (United States)

    Ekholm, Victor; Vazdar, Mario; Mason, Philip E.; Bialik, Erik; Walz, Marie-Madeleine; Öhrwall, Gunnar; Werner, Josephina; Rubensson, Jan-Erik; Jungwirth, Pavel; Björneholm, Olle

    2018-04-01

    Surface affinity of aqueous guanidinium chloride (GdmCl) is compared to that of aqueous tetrapropylammonium chloride (TPACl) upon addition of sodium chloride (NaCl) or disodium sulfate (Na2SO4). The experimental results have been acquired using the surface sensitive technique X-ray photoelectron spectroscopy on a liquid jet. Molecular dynamics simulations have been used to produce radial distribution functions and surface density plots. The surface affinities of both TPA+ and Gdm+ increase upon adding NaCl to the solution. With the addition of Na2SO4, the surface affinity of TPA+ increases, while that of Gdm+ decreases. From the results of MD simulations it is seen that Gdm+ and SO4 2 - ions form pairs. This finding can be used to explain the decreased surface affinity of Gdm+ when co-dissolved with SO4 2 - ions. Since SO4 2 - ions avoid the surface due to the double charge and strong water interaction, the Gdm+-SO4 2 - ion pair resides deeper in the solutions' bulk than the Gdm+ ions. Since TPA+ does not form ion pairs with SO4 2 -, the TPA+ ions are instead enriched at the surface.

  7. Optimal Lunar Landing Trajectory Design for Hybrid Engine

    OpenAIRE

    Cho, Dong-Hyun; Kim, Donghoon; Leeghim, Henzeh

    2015-01-01

    The lunar landing stage is usually divided into two parts: deorbit burn and powered descent phases. The optimal lunar landing problem is likely to be transformed to the trajectory design problem on the powered descent phase by using continuous thrusters. The optimal lunar landing trajectories in general have variety in shape, and the lunar lander frequently increases its altitude at the initial time to obtain enough time to reduce the horizontal velocity. Due to the increment in the altitude,...

  8. Precision Lunar Laser Ranging For Lunar and Gravitational Science

    Science.gov (United States)

    Merkowitz, S. M.; Arnold, D.; Dabney, P. W.; Livas, J. C.; McGarry, J. F.; Neumann, G. A.; Zagwodzki, T. W.

    2008-01-01

    Laser ranging to retroreflector arrays placed on the lunar surface by the Apollo astronauts and the Soviet Lunar missions over the past 39 years have dramatically increased our understanding of gravitational physics along with Earth and Moon geophysics, geodesy, and dynamics. Significant advances in these areas will require placing modern retroreflectors and/or active laser ranging systems at new locations on the lunar surface. Ranging to new locations will enable better measurements of the lunar librations, aiding in our understanding of the interior structure of the moon. More precise range measurements will allow us to study effects that are too small to be observed by the current capabilities as well as enabling more stringent tests of Einstein's theory of General Relativity. Setting up retroreflectors was a key part of the Apollo missions so it is natural to ask if future lunar missions should include them as well. The Apollo retroreflectors are still being used today, and nearly 40 years of ranging data has been invaluable for scientific as well as other studies such as orbital dynamics. However, the available retroreflectors all lie within 26 degrees latitude of the equator, and the most useful ones within 24 degrees longitude of the sub-earth meridian. This clustering weakens their geometrical strength.

  9. Lunar feldspathic meteorites: Constraints on the geology of the lunar highlands, and the origin of the lunar crust

    Science.gov (United States)

    Gross, Juliane; Treiman, Allan H.; Mercer, Celestine N.

    2014-02-01

    The composition of the lunar crust provides clues about the processes that formed it and hence contains information on the origin and evolution of the Moon. Current understanding of lunar evolution is built on the Lunar Magma Ocean hypothesis that early in its history, the Moon was wholly or mostly molten. This hypothesis is based on analyses of Apollo samples of ferroan anorthosites (>90% plagioclase; molar Mg/(Mg+Fe)=Mg#Moon's surface, and remote sensing data, show that ferroan anorthosites are not globally distributed and that the Apollo highland samples, used as a basis for the model, are influenced by ejecta from the Imbrium basin. In this study we evaluate anorthosites from all currently available adequately described lunar highland meteorites, representing a more widespread sampling of the lunar highlands than Apollo samples alone, and find that ∼80% of them are significantly more magnesian than Apollo ferroan anorthosites. Interestingly, Luna mission anorthosites, collected outside the continuous Imbrium ejecta, are also highly magnesian. If the lunar highland crust consists dominantly of magnesian anorthosites, as suggested by their abundance in samples sourced outside Imbrium ejecta, a reevaluation of the Lunar Magma Ocean model is a sensible step forward in the endeavor to understand lunar evolution. Our results demonstrate that lunar anorthosites are more similar in their chemical trends and mineral abundance to terrestrial massif anorthosites than to anorthosites predicted in a Lunar Magma Ocean. This analysis does not invalidate the idea of a Lunar Magma Ocean, which seems a necessity under the giant impact hypothesis for the origin of the moon. However, it does indicate that most rocks now seen at the Moon's surface are not primary products of a magma ocean alone, but are products of more complex crustal processes.

  10. Lunar Dust and Lunar Simulant Activation, Monitoring, Solution and Cellular Toxicity Properties

    Science.gov (United States)

    Wallace, William; Jeevarajan, A. S.

    2009-01-01

    During the Apollo missions, many undesirable situations were encountered that must be mitigated prior to returning humans to the moon. Lunar dust (that part of the lunar regolith less than 20 microns in diameter) was found to produce several problems with mechanical equipment and could have conceivably produced harmful physiological effects for the astronauts. For instance, the abrasive nature of the dust was found to cause malfunctions of various joints and seals of the spacecraft and suits. Additionally, though efforts were made to exclude lunar dust from the cabin of the lunar module, a significant amount of material nonetheless found its way inside. With the loss of gravity correlated with ascent from the lunar surface, much of the finer fraction of this dust began to float and was inhaled by the astronauts. The short visits tothe Moon during Apollo lessened exposure to the dust, but the plan for future lunar stays of up to six months demands that methods be developed to minimize the risk of dust inhalation. The guidelines for what constitutes "safe" exposure will guide the development of engineering controls aimed at preventing the presence of dust in the lunar habitat. This work has shown the effects of grinding on the activation level of lunar dust, the changes in dissolution properties of lunar simulant, and the production of cytokines by cellular systems. Grinding of lunar dust leads to the production of radicals in solution and increased dissolution of lunar simulant in buffers of different pH. Additionally, ground lunar simulant has been shown to promote the production of IL-6 and IL-8, pro-inflammatory cytokines, by alveolar epithelial cells. These results provide evidence of the need for further studies on these materials prior to returning to the lunar surface.

  11. Numerical Simulations of the Lunar Penetrating Radar and Investigations of the Geological Structures of the Lunar Regolith Layer at the Chang’E 3 Landing Site

    OpenAIRE

    Ding, Chunyu; Su, Yan; Xing, Shuguo; Dai, Shun; Xiao, Yuan; Feng, Jianqing; Liu, Danqing; Li, Chunlai

    2017-01-01

    In the process of lunar exploration, and specifically when studying lunar surface structure and thickness, the established lunar regolith model is usually a uniform and ideal structural model, which is not well-suited to describe the real structure of the lunar regolith layer. The present study aims to explain the geological structural information contained in the channel 2 LPR (lunar penetrating radar) data. In this paper, the random medium theory and Apollo drilling core data are used to co...

  12. The Age of Lunar South Circumpolar Craters Haworth, Shoemaker, Faustini, and Shackleton: Implications for Regional Geology, Surface Processes, and Volatile Sequestration

    Science.gov (United States)

    Tye, A. R.; Fassett, C. I.; Head, J. W.; Mazarico, E.; Basilevsky, A. T.; Neumann, G. A.; Smith, D. E.; Zuber, M. T.

    2015-01-01

    The interiors of the lunar south circumpolar craters Haworth, Shoemaker, Faustini, and Shackleton contain permanently shadowed regions (PSRs) and have been interpreted to contain sequestered volatiles including water ice. Altimetry data from the Lunar Orbiter Laser Altimeter (LOLA) onboard the Lunar Reconnaissance Orbiter provide a new means of examining the permanently shadowed interiors of these craters in unprecedented detail. In this study, we used extremely high-resolution gridded LOLA data of Haworth, Shoemaker, Faustini, and Shackleton to determine the size-frequency distributions and the spatial density of craters superposing their rims, inner slopes, and floors. Based on their population of superposed D greater than or equal to 2 km craters, Haworth, Shoemaker, and Faustini have pre-Nectarian formation ages. Shackleton is interpreted as having a Late Imbrian age on the basis of craters with diameter D greater than or equal to 0.5 km superposed on its rim. The local density of craters with sub-km diameters across our study area is strongly dependent on slope; because of its steep interior slopes, the lifetime of craters on the interior of Shackleton is limited. The slope-dependence of the small crater population implies that the population in this size range is controlled primarily by the rate at which craters are destroyed. This is consistent with the hypothesis that crater removal and resurfacing is a result of slopedependent processes such as diffusive mass wasting and seismic shaking, linked to micrometeorite and meteorite bombardment. Epithermal neutron flux data and UV albedo data show that these circumpolar PSRs, particularly Shoemaker, may have approximately 1-2% water ice by mass in their highly porous surface regolith, and that Shoemaker may have approximately 5% or more water ice by mass in the near subsurface. The ancient formation ages of Shoemaker, Faustini and Haworth, and the Late Imbrian (approximately 3.5 Ga) crater retention ages of their

  13. The Lunar Orbiter Laser Altimeter (LOLA) on NASA's Lunar Reconnaissance Orbiter (LRO) mission

    Science.gov (United States)

    Riris, H.; Cavanaugh, J.; Sun, X.; Liiva, P.; Rodriguez, M.; Neuman, G.

    2017-11-01

    The Lunar Orbiter Laser Altimeter (LOLA) instrument [1-3] on NASA's Lunar Reconnaissance Orbiter (LRO) mission, launched on June 18th, 2009, from Kennedy Space Center, Florida, will provide a precise global lunar topographic map using laser altimetry. LOLA will assist in the selection of landing sites on the Moon for future robotic and human exploration missions and will attempt to detect the presence of water ice on or near the surface, which is one of the objectives of NASA's Exploration Program. Our present knowledge of the topography of the Moon is inadequate for determining safe landing areas for NASA's future lunar exploration missions. Only those locations, surveyed by the Apollo missions, are known with enough detail. Knowledge of the position and characteristics of the topographic features on the scale of a lunar lander are crucial for selecting safe landing sites. Our present knowledge of the rest of the lunar surface is at approximately 1 km kilometer level and in many areas, such as the lunar far side, is on the order of many kilometers. LOLA aims to rectify that and provide a precise map of the lunar surface on both the far and near side of the moon. LOLA uses short (6 ns) pulses from a single laser through a Diffractive Optical Element (DOE) to produce a five-beam pattern that illuminates the lunar surface. For each beam, LOLA measures the time of flight (range), pulse spreading (surface roughness), and transmit/return energy (surface reflectance). LOLA will produce a high-resolution global topographic model and global geodetic framework that enables precise targeting, safe landing, and surface mobility to carry out exploratory activities. In addition, it will characterize the polar illumination environment, and image permanently shadowed regions of the lunar surface to identify possible locations of surface ice crystals in shadowed polar craters.

  14. New Age for Lunar Exploration

    Science.gov (United States)

    Taylor, G. J.; Martel, L. M. V.

    2018-04-01

    Lunar-focused research and plans to return to the lunar surface for science and exploration have reemerged since the Space Policy Directive-1 of December 11, 2017 amended the National Space Policy to include the following, "Lead an innovative and sustainable program of exploration with commercial and international partners to enable human expansion across the solar system and to bring back to Earth new knowledge and opportunities. Beginning with missions beyond low-Earth orbit, the United States will lead the return of humans to the Moon for long-term exploration and utilization, followed by human missions to Mars and other destinations." In response to this revision, NASA proposes a Lunar Exploration and Discovery Program in the U.S. fiscal year 2019 Budget Request. It supports NASA's interests in commercial and international partnerships in Low-Earth Orbit (LEO), long-term exploration in Cislunar space beyond LEO, and research and exploration conducted on the Moon to inform future crewed missions, even to destinations beyond the Moon. (Cislunar refers to the volume of space between LEO and the Moon's orbital distance.) The lunar campaign strengthens the integration of human and robotic activities on the lunar surface with NASA's science, technology, and exploration goals.

  15. Transient thermal stresses in an orthotropic finite rectangular plate due to arbitrary surface heat-generations

    International Nuclear Information System (INIS)

    Sugano, Y.

    1980-01-01

    The transient thermal stresses in an orthotropic finite rectangular plate due to arbitrary surface heat-generations on two edges are studied by means of the Airy stress function. The purposes of this paper are to present a method of determing the transient thermal stresses in an orthographic rectangular plate with four edges of distinct thermal boundary condition of the third kind which exactly satisfy the traction-free conditions of shear stress over all boundaries including four corners of the plate, and to consider the effects of the anisotropies of material properties and the convective heat transfer on the upper and lower surfaces on the thermal stress distribution. (orig.)

  16. The Lunar Potential Determination Using Apollo-Era Data and Modern Measurements and Models

    Science.gov (United States)

    Collier, Michael R.; Farrell, William M.; Espley, Jared; Webb, Phillip; Stubbs, Timothy J.; Webb, Phillip; Hills, H. Kent; Delory, Greg

    2008-01-01

    Since the Apollo era the electric potential of the Moon has been a subject of interest and debate. Deployed by three Apollo missions, Apollo 12, Apollo 14 and Apollo 15, the Suprathermal Ion Detector Experiment (SIDE) determined the sunlit lunar surface potential to be about +10 Volts using the energy spectra of lunar ionospheric thermal ions accelerated toward the Moon. More recently, the Lunar Prospector (LP) Electron Reflectometer used electron distributions to infer negative lunar surface potentials, primarily in shadow. We will present initial results from a study to combine lunar surface potential measurements from both SIDE and the LP/Electron Reflectometer to calibrate an advanced model of lunar surface charging which includes effects from the plasma environment, photoemission, secondaries ejected by ion impact onto the lunar surface, and the lunar wake created downstream by the solar wind-lunar interaction.

  17. Optimal Lunar Landing Trajectory Design for Hybrid Engine

    Directory of Open Access Journals (Sweden)

    Dong-Hyun Cho

    2015-01-01

    Full Text Available The lunar landing stage is usually divided into two parts: deorbit burn and powered descent phases. The optimal lunar landing problem is likely to be transformed to the trajectory design problem on the powered descent phase by using continuous thrusters. The optimal lunar landing trajectories in general have variety in shape, and the lunar lander frequently increases its altitude at the initial time to obtain enough time to reduce the horizontal velocity. Due to the increment in the altitude, the lunar lander requires more fuel for lunar landing missions. In this work, a hybrid engine for the lunar landing mission is introduced, and an optimal lunar landing strategy for the hybrid engine is suggested. For this approach, it is assumed that the lunar lander retrofired the impulsive thruster to reduce the horizontal velocity rapidly at the initiated time on the powered descent phase. Then, the lunar lander reduced the total velocity and altitude for the lunar landing by using the continuous thruster. In contradistinction to other formal optimal lunar landing problems, the initial horizontal velocity and mass are not fixed at the start time. The initial free optimal control theory is applied, and the optimal initial value and lunar landing trajectory are obtained by simulation studies.

  18. Lunar floor-fractured craters: Modes of dike and sill emplacement and implications of gas production and intrusion cooling on surface morphology and structure

    Science.gov (United States)

    Wilson, Lionel; Head, James W.

    2018-05-01

    Lunar floor-fractured craters (FFCs) represent the surface manifestation of a class of shallow crustal intrusions in which magma-filled cracks (dikes) rising to the surface from great depth encounter contrasts in host rock lithology (breccia lens, rigid solidified melt sheet) and intrude laterally to form a sill, laccolith or bysmalith, thereby uplifting and deforming the crater floor. Recent developments in the knowledge of lunar crustal thickness and density structure have enabled important revisions to models of the generation, ascent and eruption of magma, and new knowledge about the presence and behavior of magmatic volatiles has provided additional perspectives on shallow intrusion processes in FFCs. We use these new data to assess the processes that occur during dike and sill emplacement with particular emphasis on tracking the fate and migration of volatiles and their relation to candidate venting processes. FFCs result when dikes are capable of intruding close to the surface, but fail to erupt because of the substructure of their host impact craters, and instead intrude laterally after encountering a boundary where an increase in ductility (base of breccia lens) or rigidity (base of solidified melt sheet) occurs. Magma in dikes approaching the lunar surface experiences increasingly lower overburden pressures: this enhances CO gas formation and brings the magma into the realm of the low pressure release of H2O and sulfur compounds, both factors adding volatiles to those already collected in the rising low-pressure part of the dike tip. High magma rise velocity is driven by the positive buoyancy of the magma in the part of the dike remaining in the mantle. The dike tip overshoots the interface and the consequent excess pressure at the interface drives the horizontal flow of magma to form the intrusion and raise the crater floor. If sill intrusion were controlled by the physical properties at the base of the melt sheet, dikes would be required to approach to

  19. Nonlinear radiation of waves at combination frequencies due to radiation-surface wave interaction in plasmas

    International Nuclear Information System (INIS)

    El Naggar, I.A.; Hussein, A.M.; Khalil, Sh.M.

    1992-09-01

    Electromagnetic waves radiated with combination frequencies from a semi-bounded plasma due to nonlinear interaction of radiation with surface wave (both of P-polarization) has been investigated. Waves are radiated both into vacuum and plasma are found to be P-polarized. We take into consideration the continuity at the plasma boundary of the tangential components of the electric field of the waves. The case of normal incidence of radiation and rarefield plasma layer is also studied. (author). 7 refs

  20. Assessment of surface and subsurface ground disturbance due to underground mining

    International Nuclear Information System (INIS)

    Khair, A.W.

    1994-01-01

    This paper presents highlights of the research carried out at West Virginia University in order to assess surface and subsurface ground disturbance due to longwall mining. Extensive instrumentation and measurements have been made over three longwall mines in northern West Virginia during a three-year period. Various monitoring techniques including full profile borehole extensometer, full profile borehole inclinometers, time domain reflectometry, sonic reflection technique, a unique mechanical grouting method, photographic and visual observations, standard surveying, and water-level measurements were utilized. The paper's emphasis is first on surface ground movement and its impact on integrity of surface ground and structures and second on type and magnitude of subsurface ground movements associated with mine geometry and geology. A subsidence prediction model based on implementation of both mechanisms of ground movement around the excavation and the geologic and geotechnical properties of the rock/coal surrounding the excavation has been developed. 8 refs., 14 figs., 1 tab

  1. Spacesuit Integrated Carbon Nanotube Dust Mitigation System for Lunar Exploration

    Science.gov (United States)

    Manyapu, Kavya Kamal

    Lunar dust proved to be troublesome during the Apollo missions. The lunar dust comprises of fine particles, with electric charges imparted by solar winds and ultraviolet radiation. As such, it adheres readily, and easily penetrates through smallest crevices into mechanisms. During Apollo missions, the powdery dust substantially degraded the performance of spacesuits by abrading suit fabric and clogging seals. Dust also degraded other critical equipment such as rovers, thermal control and optical surfaces, solar arrays, and was thus shown to be a major issue for surface operations. Even inside the lunar module, Apollo astronauts were exposed to this dust when they removed their dust coated spacesuits. This historical evidence from the Apollo missions has compelled NASA to identify dust mitigation as a critical path. This important environmental challenge must be overcome prior to sending humans back to the lunar surface and potentially to other surfaces such as Mars and asteroids with dusty environments. Several concepts were successfully investigated by the international research community for preventing deposition of lunar dust on rigid surfaces (ex: solar cells, thermal radiators). However, applying these technologies for flexible surfaces and specifically to spacesuits has remained an open challenge, due to the complexity of the suit design, geometry, and dynamics. The research presented in this dissertation brings original contribution through the development and demonstration of the SPacesuit Integrated Carbon nanotube Dust Ejection/Removal (SPIcDER) system to protect spacesuits and other flexible surfaces from lunar dust. SPIcDER leverages the Electrodynamic Dust Shield (EDS) concept developed at NASA for use on solar cells. For the SPIcDER research, the EDS concept is customized for application on spacesuits and flexible surfaces utilizing novel materials and specialized design techniques. Furthermore, the performance of the active SPIcDER system is enhanced

  2. Methodology for estimation of time-dependent surface heat flux due to cryogen spray cooling.

    Science.gov (United States)

    Tunnell, James W; Torres, Jorge H; Anvari, Bahman

    2002-01-01

    Cryogen spray cooling (CSC) is an effective technique to protect the epidermis during cutaneous laser therapies. Spraying a cryogen onto the skin surface creates a time-varying heat flux, effectively cooling the skin during and following the cryogen spurt. In previous studies mathematical models were developed to predict the human skin temperature profiles during the cryogen spraying time. However, no studies have accounted for the additional cooling due to residual cryogen left on the skin surface following the spurt termination. We formulate and solve an inverse heat conduction (IHC) problem to predict the time-varying surface heat flux both during and following a cryogen spurt. The IHC formulation uses measured temperature profiles from within a medium to estimate the surface heat flux. We implement a one-dimensional sequential function specification method (SFSM) to estimate the surface heat flux from internal temperatures measured within an in vitro model in response to a cryogen spurt. Solution accuracy and experimental errors are examined using simulated temperature data. Heat flux following spurt termination appears substantial; however, it is less than that during the spraying time. The estimated time-varying heat flux can subsequently be used in forward heat conduction models to estimate temperature profiles in skin during and following a cryogen spurt and predict appropriate timing for onset of the laser pulse.

  3. Tritium surface loading due to contamination of rainwater from atmospheric release at NAPS

    International Nuclear Information System (INIS)

    Sharma, L.N.; Dube, B.; Varakhedkar, V.K.

    2001-01-01

    Annual tritium (HTO) surface loading has been measured and calculated for the year 1998-99 within 0.8 km distance from 145m high stack of Narora Atomic Power Station (NAPS) at eight locations in different directions. The technique for measured values consists of the summation of product of tritium concentration (Bq/l) in daily rainfall samples and daily rainfall (mm) whereas that for calculated values having the use of prevailing meteorological conditions and average tritium release rate during a year. The ratios of measured and calculated values of tritium surface loading during the years 1998-99 are found to be in the range of 0.18 to 6.97. Tritium surface loading studies at NAPS reveal that a fraction 1.7E-03 of total annual tritium released through stack gets deposited on the surface due to washout / rainout of plume within 0.8 km radial distance from stack. The range of deposition velocity, V w (m.s - 1 ) i.e the ratio of annual tritium surface loading W(Bq.m - 2 . s - 1 ) and annual mean tritium concentration in air, χo(Bq.m - 3) at three locations for the years 1998-99 is found to be 5.59E-04 to 5.99E-03 ms - 1 . The average value for wet deposition velocity V bar w for NAPS site is estimated as 2.92E-03 m.s - 1. (author)

  4. Building an Economical and Sustainable Lunar Infrastructure to Enable Lunar Industrialization

    Science.gov (United States)

    Zuniga, Allison F.; Turner, Mark; Rasky, Daniel; Loucks, Mike; Carrico, John; Policastri, Daniel

    2017-01-01

    A new concept study was initiated to examine the architecture needed to gradually develop an economical, evolvable and sustainable lunar infrastructure using a public/private partnerships approach. This approach would establish partnership agreements between NASA and industry teams to develop a lunar infrastructure system that would be mutually beneficial. This approach would also require NASA and its industry partners to share costs in the development phase and then transfer operation of these infrastructure services back to its industry owners in the execution phase. These infrastructure services may include but are not limited to the following: lunar cargo transportation, power stations, communication towers and satellites, autonomous rover operations, landing pads and resource extraction operations. The public/private partnerships approach used in this study leveraged best practices from NASA's Commercial Orbital Transportation Services (COTS) program which introduced an innovative and economical approach for partnering with industry to develop commercial cargo services to the International Space Station. This program was planned together with the ISS Commercial Resupply Services (CRS) contracts which was responsible for initiating commercial cargo delivery services to the ISS for the first time. The public/private partnerships approach undertaken in the COTS program proved to be very successful in dramatically reducing development costs for these ISS cargo delivery services as well as substantially reducing operational costs. To continue on this successful path towards installing economical infrastructure services for LEO and beyond, this new study, named Lunar COTS (Commercial Operations and Transport Services), was conducted to examine extending the NASA COTS model to cis-lunar space and the lunar surface. The goals of the Lunar COTS concept are to: 1) develop and demonstrate affordable and commercial cis-lunar and surface capabilities, such as lunar cargo

  5. APOLLO 10 ASTRONAUT ENTERS LUNAR MODULE SIMULATOR

    Science.gov (United States)

    1969-01-01

    Apollo 10 lunar module pilot Eugene A. Cernan prepares to enter the lunar module simulator at the Flight Crew Training Building at the NASA Spaceport. Cernan, Apollo 10 commander Thomas P. Stafford and John W. Young, command module pilot, are to be launched May 18 on the Apollo 10 mission, a dress rehearsal for a lunar landing later this summer. Cernan and Stafford are to detach the lunar module and drop to within 10 miles of the moon's surface before rejoining Young in the command/service module. Looking on as Cernan puts on his soft helmet is Snoopy, the lovable cartoon mutt whose name will be the lunar module code name during the Apollo 10 flight. The command/service module is to bear the code name Charlie Brown.

  6. Burn Delay Analysis of the Lunar Orbit Insertion for Korea Pathfinder Lunar Orbiter

    Science.gov (United States)

    Bae, Jonghee; Song, Young-Joo; Kim, Young-Rok; Kim, Bangyeop

    2017-12-01

    The first Korea lunar orbiter, Korea Pathfinder Lunar Orbiter (KPLO), has been in development since 2016. After launch, the KPLO will execute several maneuvers to enter into the lunar mission orbit, and will then perform lunar science missions for one year. Among these maneuvers, the lunar orbit insertion (LOI) is the most critical maneuver because the KPLO will experience an extreme velocity change in the presence of the Moon’s gravitational pull. However, the lunar orbiter may have a delayed LOI burn during operation due to hardware limitations and telemetry delays. This delayed burn could occur in different captured lunar orbits; in the worst case, the KPLO could fly away from the Moon. Therefore, in this study, the burn delay for the first LOI maneuver is analyzed to successfully enter the desired lunar orbit. Numerical simulations are performed to evaluate the difference between the desired and delayed lunar orbits due to a burn delay in the LOI maneuver. Based on this analysis, critical factors in the LOI maneuver, the periselene altitude and orbit period, are significantly changed and an additional delta-V in the second LOI maneuver is required as the delay burn interval increases to 10 min from the planned maneuver epoch.

  7. Electrostatic Power Generation from Negatively Charged, Simulated Lunar Regolith

    Science.gov (United States)

    Choi, Sang H.; King, Glen C.; Kim, Hyun-Jung; Park, Yeonjoon

    2010-01-01

    Research was conducted to develop an electrostatic power generator for future lunar missions that facilitate the utilization of lunar resources. The lunar surface is known to be negatively charged from the constant bombardment of electrons and protons from the solar wind. The resulting negative electrostatic charge on the dust particles, in the lunar vacuum, causes them to repel each other minimizing the potential. The result is a layer of suspended dust about one meter above the lunar surface. This phenomenon was observed by both Clementine and Surveyor spacecrafts. During the Apollo 17 lunar landing, the charged dust was a major hindrance, as it was attracted to the astronauts' spacesuits, equipment, and the lunar buggies. The dust accumulated on the spacesuits caused reduced visibility for the astronauts, and was unavoidably transported inside the spacecraft where it caused breathing irritation [1]. In the lunar vacuum, the maximum charge on the particles can be extremely high. An article in the journal "Nature", titled "Moon too static for astronauts?" (Feb 2, 2007) estimates that the lunar surface is charged with up to several thousand volts [2]. The electrostatic power generator was devised to alleviate the hazardous effects of negatively charged lunar soil by neutralizing the charged particles through capacitive coupling and thereby simultaneously harnessing power through electric charging [3]. The amount of power generated or collected is dependent on the areal coverage of the device and hovering speed over the lunar soil surface. A thin-film array of capacitors can be continuously charged and sequentially discharged using a time-differentiated trigger discharge process to produce a pulse train of discharge for DC mode output. By controlling the pulse interval, the DC mode power can be modulated for powering devices and equipment. In conjunction with a power storage system, the electrostatic power generator can be a power source for a lunar rover or other

  8. Estimation of Surface Deformation due to Pasni Earthquake Using SAR Interferometry

    Science.gov (United States)

    Ali, M.; Shahzad, M. I.; Nazeer, M.; Kazmi, J. H.

    2018-04-01

    Earthquake cause ground deformation in sedimented surface areas like Pasni and that is a hazard. Such earthquake induced ground displacements can seriously damage building structures. On 7 February 2017, an earthquake with 6.3 magnitudes strike near to Pasni. We have successfully distinguished widely spread ground displacements for the Pasni earthquake by using InSAR-based analysis with Sentinel-1 satellite C-band data. The maps of surface displacement field resulting from the earthquake are generated. Sentinel-1 Wide Swath data acquired from 9 December 2016 to 28 February 2017 was used to generate displacement map. The interferogram revealed the area of deformation. The comparison map of interferometric vertical displacement in different time period was treated as an evidence of deformation caused by earthquake. Profile graphs of interferogram were created to estimate the vertical displacement range and trend. Pasni lies in strong earthquake magnitude effected area. The major surface deformation areas are divided into different zones based on significance of deformation. The average displacement in Pasni is estimated about 250 mm. Maximum pasni area is uplifted by earthquake and maximum uplifting occurs was about 1200 mm. Some of areas was subsidized like the areas near to shoreline and maximum subsidence was estimated about 1500 mm. Pasni is facing many problems due to increasing sea water intrusion under prevailing climatic change where land deformation due to a strong earthquake can augment its vulnerability.

  9. Damping of surface waves due to oil emulsions in application to ocean remote sensing

    Science.gov (United States)

    Sergievskaya, I.; Ermakov, S.; Lazareva, T.; Lavrova, O.

    2017-10-01

    Applications of different radar and optical methods for detection of oil pollutions based on the effect of damping of short wind waves by surface films have been extensively studied last decades. The main problem here is poor knowledge of physical characteristics of oil films, in particular, emulsified oil layers (EOL). The latter are ranged up to 70% of all pollutants. Physical characteristics of EOL which are responsible for wave damping and respectively for possibilities of their remote sensing depend on conditions of emulsification processes, e.g., mixing due to wave breaking, on percentage of water in the oil, etc. and are not well studied by now. In this paper results of laboratory studies of damping of gravity-capillary waves due to EOL on water are presented and compared to oil layers (OL). A laboratory method used previously for monomolecular films and OL, and based on measuring the damping coefficient and wavelength of parametrically generated standing waves has been applied for determination of EOL characteristics. Investigations of characteristics of crude oil, oil emulsions and crude OL and EOL have been carried out in a wide range of surface wave frequencies (from 10 to 25 Hz) and OL and EOL film thickness (from hundredths of millimeter to a few millimeters. The selected frequency range corresponds to Bragg waves for microwave, X- to Ka-band radars typically used for ocean remote sensing. An effect of enhanced wave damping due to EOL compared to non emulsified crude OL is revealed.

  10. Increased dose near the skin due to electromagnetic surface beacon transponder.

    Science.gov (United States)

    Ahn, Kang-Hyun; Manger, Ryan; Halpern, Howard J; Aydogan, Bulent

    2015-05-08

    The purpose of this study was to evaluate the increased dose near the skin from an electromagnetic surface beacon transponder, which is used for localization and tracking organ motion. The bolus effect due to the copper coil surface beacon was evaluated with radiographic film measurements and Monte Carlo simulations. Various beam incidence angles were evaluated for both 6 MV and 18 MV experimentally. We performed simulations using a general-purpose Monte Carlo code MCNPX (Monte Carlo N-Particle) to supplement the experimental data. We modeled the surface beacon geometry using the actual mass of the glass vial and copper coil placed in its L-shaped polyethylene terephthalate tubing casing. Film dosimetry measured factors of 2.2 and 3.0 enhancement in the surface dose for normally incident 6 MV and 18 MV beams, respectively. Although surface dose further increased with incidence angle, the relative contribution from the bolus effect was reduced at the oblique incidence. The enhancement factors were 1.5 and 1.8 for 6 MV and 18 MV, respectively, at an incidence angle of 60°. Monte Carlo simulation confirmed the experimental results and indicated that the epidermal skin dose can reach approximately 50% of the dose at dmax at normal incidence. The overall effect could be acceptable considering the skin dose enhancement is confined to a small area (~ 1 cm2), and can be further reduced by using an opposite beam technique. Further clinical studies are justified in order to study the dosimetric benefit versus possible cosmetic effects of the surface beacon. One such clinical situation would be intact breast radiation therapy, especially large-breasted women.

  11. Tritium surface loading due to contamination of rainwater from atmospheric release at NAPS (2011)

    International Nuclear Information System (INIS)

    Gautam, Y.P.; Sharma, Saivajay; Rao, K.S.; Singh, Bhikam; Kumar, Avinash; Ravi, P.M.

    2012-01-01

    Annual tritium (HTO) surface loading has been measured and calculated for the year 2011 within 0.8 km distance from 145 m high stack of Narora Atomic Power Station (NAPS) at eight locations in different directions. The technique for measured values consists of the summation of product of tritium concentration (Bq/l) in daily rainfall samples and daily rainfall (mm). Tritium surface loading studies at NAPS reveal that a fraction 1.01E-03 of total annual tritium released through stack gets deposited on the surface due to washout/rainout of plume within 0.8 km radial distance from stack. The range of deposition velocity, Vw (m.s -1 ) i.e., the ratio of annual tritium surface loading W (Bq. m -2 .s -1 ) and annual mean tritium concentration in air, c 0 (Bq.m -3 ) at three locations for the years 2011 is found to be 6.12E-04 to 2.89E-03. The average value for wet deposition velocity V w for NAPS site is estimated as 3.17E-03 m.s -1 . (author)

  12. Investigations of surface-tension effects due to small-scale complex boundaries

    Science.gov (United States)

    Feng, Jiansheng

    In this Ph.D. dissertation, we have investigated some important surface-tension phenomena including capillarity, wetting, and wicking. We mainly focus on the geometric aspects of these problems, and to learn about how structures affect properties. . In the first project (Chapter 2), we used numerical simulations and experiments to study the meniscus of a fluid confined in capillaries with complicated cross-sectional geometries. In the simulations, we computed the three-dimensional shapes of the menisci formed in polygonal and star-shaped capillaries with sharp or rounded corners. Height variations across the menisci were used to quantify the effect of surface tension. Analytical solutions were derived for all the cases where the cross-sectional geometry was a regular polygon or a regular star-shape. Power indices that characterize the effects of corner rounding were extracted from simulation results. These findings can serve as guide for fabrications of unconventional three-dimensional structures in Capillary Force Lithography experiments. Experimental demonstrations of the working principle was also performed. Although quantitative matching between simulation and experimental results was not achieved due to the limitation of material properties, clear qualitative trends were observed and interesting three-dimensional nano-structures were produced. A second project (Chapter 3) focused on developing techniques to produce three-dimensional hierarchically structured superhydrophobic surfaces with high aspect ratios. We experimented with two different high-throughput electron-beam-lithography processes featuring single and dual electron-beam exposures. After a surface modification procedure with a hydrophobic silane, the structured surfaces exhibited two distinct superhydrophobic behaviors---high and low adhesion. While both types of superhydrophobic surfaces exhibited very high (approximately 160° water advancing contact angles, the water receding contact angles on

  13. Summary of the results from the lunar orbiter laser altimeter after seven years in lunar orbit

    Science.gov (United States)

    Smith, David E.; Zuber, Maria T.; Neumann, Gregory A.; Mazarico, Erwan; Lemoine, Frank G.; Head, James W., III; Lucey, Paul G.; Aharonson, Oded; Robinson, Mark S.; Sun, Xiaoli; Torrence, Mark H.; Barker, Michael K.; Oberst, Juergen; Duxbury, Thomas C.; Mao, Dandan; Barnouin, Olivier S.; Jha, Kopal; Rowlands, David D.; Goossens, Sander; Baker, David; Bauer, Sven; Gläser, Philipp; Lemelin, Myriam; Rosenburg, Margaret; Sori, Michael M.; Whitten, Jennifer; Mcclanahan, Timothy

    2017-02-01

    In June 2009 the Lunar Reconnaissance Orbiter (LRO) spacecraft was launched to the Moon. The payload consists of 7 science instruments selected to characterize sites for future robotic and human missions. Among them, the Lunar Orbiter Laser Altimeter (LOLA) was designed to obtain altimetry, surface roughness, and reflectance measurements. The primary phase of lunar exploration lasted one year, following a 3-month commissioning phase. On completion of its exploration objectives, the LRO mission transitioned to a science mission. After 7 years in lunar orbit, the LOLA instrument continues to map the lunar surface. The LOLA dataset is one of the foundational datasets acquired by the various LRO instruments. LOLA provided a high-accuracy global geodetic reference frame to which past, present and future lunar observations can be referenced. It also obtained high-resolution and accurate global topography that were used to determine regions in permanent shadow at the lunar poles. LOLA further contributed to the study of polar volatiles through its unique measurement of surface brightness at zero phase, which revealed anomalies in several polar craters that may indicate the presence of water ice. In this paper, we describe the many LOLA accomplishments to date and its contribution to lunar and planetary science.

  14. Summary of the Results from the Lunar Orbiter Laser Altimeter after Seven Years in Lunar Orbit

    Science.gov (United States)

    Smith, David E.; Zuber, Maria T.; Neumann, Gregory A.; Mazarico, Erwan; Lemoine, Frank G.; Head, James W., III; Lucey, Paul G.; Aharonson, Oded; Robinson, Mark S.; Sun, Xiaoli; hide

    2016-01-01

    In June 2009 the Lunar Reconnaissance Orbiter (LRO) spacecraft was launched to the Moon. The payload consists of 7 science instruments selected to characterize sites for future robotic and human missions. Among them, the Lunar Orbiter Laser Altimeter (LOLA) was designed to obtain altimetry, surface roughness, and reflectance measurements. The primary phase of lunar exploration lasted one year, following a 3-month commissioning phase. On completion of its exploration objectives, the LRO mission transitioned to a science mission. After 7 years in lunar orbit, the LOLA instrument continues to map the lunar surface. The LOLA dataset is one of the foundational datasets acquired by the various LRO instruments. LOLA provided a high-accuracy global geodetic reference frame to which past, present and future lunar observations can be referenced. It also obtained high-resolution and accurate global topography that were used to determine regions in permanent shadow at the lunar poles. LOLA further contributed to the study of polar volatiles through its unique measurement of surface brightness at zero phase, which revealed anomalies in several polar craters that may indicate the presence of water ice. In this paper, we describe the many LOLA accomplishments to date and its contribution to lunar and planetary science.

  15. On The Development of Additive Construction Technologies for Application to Development of Lunar/Martian Surface Structures Using In-Situ Materials

    Science.gov (United States)

    Werkheiser, Niki; Fiske, Michael; Edmunson, Jennifer; Khoshnevis, Behrokh

    2015-01-01

    For long-duration missions on other planetary bodies, the use of in-situ materials will become increasingly critical. As man's presence on these bodies expands, so must the breadth of the structures required to accommodate them including habitats, laboratories, berms, radiation shielding for natural radiation and surface reactors, garages, solar storm shelters, greenhouses, etc. Planetary surface structure manufacturing and assembly technologies that incorporate in-situ resources provide options for autonomous, affordable, pre-positioned environments with radiation shielding features and protection from micrometeorites, exhaust plume debris, and other hazards. This is important because gamma and particle radiation constitute a serious but reducible threat to long-term survival of human beings, electronics, and other materials in space environments. Also, it is anticipated that surface structures will constitute the primary mass element of lunar or Martian launch requirements. The ability to use in-situ materials to construct these structures will provide a benefit in the reduction of up-mass that would otherwise make long-term Moon or Mars structures cost prohibitive. The ability to fabricate structures in situ brings with it the ability to repair these structures, which allows for self-sufficiency necessary for long-duration habitation. Previously, under the auspices of the MSFC In Situ Fabrication and Repair (ISFR) project and more recently, under the joint MSFC/KSC Additive Construction with Mobile Emplacement (ACME) project, the MSFC Surface Structures Group has been developing materials and construction technologies to support future planetary habitats with in situ resources. One such technology, known as Contour Crafting (additive construction), is shown in Figure 1, along with a typical structure fabricated using this technology. This paper will present the results to date of these efforts, including development of novel nozzle concepts for advanced layer

  16. LADEE LUNAR DUST EXPERIMENT

    Data.gov (United States)

    National Aeronautics and Space Administration — This archive bundle includes data taken by the Lunar Dust Experiment (LDEX) instrument aboard the Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft....

  17. Endogenous Lunar Volatiles

    Science.gov (United States)

    McCubbin, F. M.; Liu, Y.; Barnes, J. J.; Anand, M.; Boyce, J. W.; Burney, D.; Day, J. M. D.; Elardo, S. M.; Hui, H.; Klima, R. L.; Magna, T.; Ni, P.; Steenstra, E.; Tartèse, R.; Vander Kaaden, K. E.

    2018-04-01

    This abstract discusses numerous outstanding questions on the topic of endogenous lunar volatiles that will need to be addressed in the coming years. Although substantial insights into endogenous lunar volatiles have been gained, more work remains.

  18. Critical Robotic Lunar Missions

    Science.gov (United States)

    Plescia, J. B.

    2018-04-01

    Perhaps the most critical missions to understanding lunar history are in situ dating and network missions. These would constrain the volcanic and thermal history and interior structure. These data would better constrain lunar evolution models.

  19. Respiratory Toxicity of Lunar Highland Dust

    Science.gov (United States)

    James, John T.; Lam, Chiu-wing; Wallace, William T.

    2009-01-01

    Lunar dust exposures occurred during the Apollo missions while the crew was on the lunar surface and especially when microgravity conditions were attained during rendezvous in lunar orbit. Crews reported that the dust was irritating to the eyes and in some cases respiratory symptoms were elicited. NASA s vision for lunar exploration includes stays of 6 months on the lunar surface hence the health effects of periodic exposure to lunar dust need to be assessed. NASA has performed this assessment with a series of in vitro and in vivo tests on authentic lunar dust. Our approach is to "calibrate" the intrinsic toxicity of lunar dust by comparison to a nontoxic dust (TiO2) and a highly toxic dust (quartz) using intratrachael instillation of the dusts in mice. A battery of indices of toxicity is assessed at various time points after the instillations. Cultures of selected cells are exposed to test dusts to assess the adverse effects on the cells. Finally, chemical systems are used to assess the nature of the reactivity of various dusts and to determine the persistence of reactivity under various environmental conditions that are relevant to a space habitat. Similar systems are used to assess the dissolution of the dust. From these studies we will be able to set a defensible inhalation exposure standard for aged dust and predict whether we need a separate standard for reactive dust. Presently-available data suggest that aged lunar highland dust is slightly toxic, that it can adversely affect cultured cells, and that the surface reactivity induced by grinding the dust persists for a few hours after activation.

  20. Lunar Dust Separation for Toxicology Studies

    Science.gov (United States)

    Cooper, Bonnie L.; McKay, D. S.; Riofrio, L. M.; Taylor, L. A.; Gonzalex, C. P.

    2010-01-01

    During the Apollo missions, crewmembers were briefly exposed to dust in the lunar module, brought in after extravehicular activity. When the lunar ascent module returned to micro-gravity, the dust that had settled on the floor now floated into the air, causing eye discomfort and occasional respiratory symptoms. Because our goal is to set an exposure standard for 6 months of episodic exposure to lunar dust for crew on the lunar surface, these brief exposures of a few days are not conclusive. Based on experience with industrial minerals such as sandblasting quartz, an exposure of several months may cause serious damage, while a short exposure may cause none. The detailed characteristics of sub-micrometer lunar dust are only poorly known, and this is the size range of particles that are of greatest concern. We have developed a method for extracting respirable dust (<2.5 micron) from Apollo lunar soils. This method meets stringent requirements that the soil must be kept dry, exposed only to pure nitrogen, and must conserve and recover the maximum amount of both respirable dust and coarser soil. In addition, we have developed a method for grinding coarser lunar soil to produce sufficient respirable soil for animal toxicity testing while preserving the freshly exposed grain surfaces in a pristine state.

  1. Assessment of damage to the desert surfaces of Kuwait due to the Gulf War

    International Nuclear Information System (INIS)

    El-Baz, F.; Al-Ajmi, D.

    1993-01-01

    This is a preliminary report on a joint research project by Boston University and the Kuwait Institute for Scientific Research that commenced in April 1992. The project aim is to establish the extent and nature of environmental damage to the desert surface and coastal zone of Kuwait due to the Gulf War and its aftermath. Change detection image enhancement techniques were employed to enhance environmental change by comparison of Landsat Thematic Mapper images obtained before the wars and after the cessation of the oil and well fires. Higher resolution SPOT images were also utilized to evaluate the nature of the environmental damage to specific areas. The most prominent changes were due to: (1) the deposition of oil and course-grained soot on the desert surface as a result of ''oil rain'' from the plume that emanated from the oil well fires; (2) the formation of hundreds of oil lakes, from oil seepage at the damaged oil well heads; (3) the mobilization of sand and dust and (4) the pollution of segments of the coastal zone by the deposition of oil from several oil spills. Interpretation of satellite image data are checked in the field to confirm the observations, and to assess the nature of the damage. Final results will be utilized in establishing the needs for remedial action to counteract the harmful effects of the various types of damage to the environment of Kuwait

  2. Surface structural damage study in cortical bone due to medical drilling.

    Science.gov (United States)

    Tavera R, Cesar G; De la Torre-I, Manuel H; Flores-M, Jorge M; Hernandez M, Ma Del Socorro; Mendoza-Santoyo, Fernando; Briones-R, Manuel de J; Sanchez-P, Jorge

    2017-05-01

    A bone's fracture could be produced by an excessive, repetitive, or sudden load. A regular medical practice to heal it is to fix it in two possible ways: external immobilization, using a ferule, or an internal fixation, using a prosthetic device commonly attached to the bone by means of surgical screws. The bone's volume loss due to this drilling modifies its structure either in the presence or absence of a fracture. To observe the bone's surface behavior caused by the drilling effects, a digital holographic interferometer is used to analyze the displacement surface's variations in nonfractured post-mortem porcine femoral bones. Several nondrilled post-mortem bones are compressed and compared to a set of post-mortem bones with a different number of cortical drillings. During each compression test, a series of digital interferometric holograms were recorded using a high-speed CMOS camera. The results are presented as pseudo 3D mesh displacement maps for comparisons in the physiological range of load (30 and 50 lbs) and beyond (100, 200, and 400 lbs). The high resolution of the optical phase gives a better understanding about the bone's microstructural modifications. Finally, a relationship between compression load and bone volume loss due to the drilling was observed. The results prove that digital holographic interferometry is a viable technique to study the conditions that avoid the surgical screw from loosening in medical procedures of this kind.

  3. Study on applicability of numerical simulation to evaluation of gas entrainment due to free surface vortex

    International Nuclear Information System (INIS)

    Ito, Kei; Kunugi, Tomoaki; Ohshima, Hiroyuki

    2008-01-01

    An onset condition of gas entrainment (GE) due to free surface vortex has been studied to establish a design of sodium-cooled fast reactor with a higher coolant velocity than conventional designs. Numerous investigations have been conducted experimentally and theoretically; however, the universal onset condition of the GE has not been determined yet due to the nonlinear characteristics of the GE. Recently, we have been studying numerical simulation methods as a promising method to evaluate GE, instead of the reliable but costly real-scale tests. In this paper, the applicability of the numerical simulation methods to the evaluation of the GE is discussed. For the purpose, a quasi-steady vortex in a cylindrical tank and a wake vortex (unsteady vortex) in a rectangular channel were numerically simulated using the volume-of-fluid type two-phase flow calculation method. The simulated velocity distributions and free surface shapes of the quasi-steady vortex showed good (not perfect, however) agreements with experimental results when a fine mesh subdivision and a high-order discretization scheme were employed. The unsteady behavior of the wake vortex was also simulated with high accuracy. Although the onset condition of the GE was slightly underestimated in the simulation results, the applicability of the numerical simulation methods to the GE evaluation was confirmed. (author)

  4. A completely automatic operation type super-safe fast reactor, RAPID. Its application to dispersion source on lunar and earth surfaces

    International Nuclear Information System (INIS)

    Kanbe, Mitsuru; Tsunoda, Hirokazu; Mishima, Kaichiro; Kawasaki, Akira; Iwamura, Takamichi

    2002-01-01

    At a viewpoint of flexible measures to future electric power demands, expectation onto a small-scale reactor for dispersion source is increasing gradually. This is thought to increase its importance not only for a source at proximity of its market in advanced nations but also for the one in developing nations. A study on development of the completely automatic operation type super-safe fast reactor, RAPID (refueling by all pins integrated design) has been carried out as a part of the nuclear energy basic research promoting system under three years project since 1999 by a trust of the Japan Atomic Energy Research Institute to a group of the Central Research Institute of Electric Power Industry (CRIEPI) and so on. As the reactor is a lithium cooled fast reactor with 200 Kw of electric output supposing to use at lunar surface, it can be applied to a super-small scale nuclear reactor on the earth, and has feasibility to become a new option of future nuclear power generation. On the other hand, CRIEPI has investigated on various types of fast reactors (RAPID series) for fast reactor for dispersion source on the earth. Here was introduced on such super-safe fast reactors at a center of RAPID-L. (G.K.)

  5. Hints of supernova debris deposition on the lunar surface: {sup 60}Fe and {sup 53}Mn measurements by means of accelerator mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Fimiani, Leticia; Faestermann, Thomas; Gomez Guzman, Jose Manuel; Hain, Karin; Korschinek, Gunther; Ludwig, Peter [Physik Department, Technische Universitaet Muenchen, Garching (Germany); Herzog, Gregory; Ligon, Bret; Park, Jisun [Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ (United States); Rugel, Georg [Forschungszentrum Dresden Rossendorf, Dresden (Germany)

    2013-07-01

    The enhanced concentration of {sup 60}Fe in a deep ocean ferro-manganese crust about (2.1±0.4) Myr old (Fitoussi et al., PRL 101, 121101 (2008)), suggests that one or more supernova (SN) explosions occurred in the vicinity of the Solar System. That observation was only possible with the ultra sensitive Accelerator Mass Spectrometry (AMS) technique at the Maier-Leibnitz-Laboratorium in Munich, where we are able to measure concentrations of {sup 60}Fe/Fe down to a level of 10{sup -16}. Because of its lacking atmosphere and negligible sedimentation rate, the Lunar surface is an excellent quantitative reservoir for SN debris. We searched for live {sup 60}Fe and {sup 53}Mn in samples from 3 Apollo missions. {sup 53}Mn is, similar as {sup 26}Al and {sup 60}Fe, a tool to trace nucleosynthesis activities. It is formed primarily during the explosive silicon-burning of the inner shells of SNe via {sup 53}Fe which β-decays to {sup 53}Mn with an 8.51 min half-life. Samples where we found an enhanced {sup 60}Fe concentration showed also an enhancement of {sup 53}Mn. If confirmed, this could be the first detection of live {sup 53}Mn originating from nucleosynthesis.

  6. Structural and surface changes in glassy carbon due to strontium implantation and heat treatment

    Science.gov (United States)

    Odutemowo, O. S.; Malherbe, J. B.; Prinsloo, L. C.; Njoroge, E. G.; Erasmus, R.; Wendler, E.; Undisz, A.; Rettenmayr, M.

    2018-01-01

    There are still questions around the microstructure of glassy carbon (GC), like the observation of the micropores. These were proposed to explain the low density of GC. This paper explains the effect of ion bombardment (200 keV Sr+, 1 × 1016 Sr+/cm2 at RT) on the microstructure of GC. TEM and AFM show that micropores in pristine GC are destroyed leading to densification of GC from 1.42 g/cm3 to 2.03 g/cm3. The amorphisation of glassy carbon was also not complete with graphitic strands embedded within the GC. These were relatively few, as Raman analysis showed that the Sr implantation resulted in a typical amorphous Raman spectrum. Annealing of the sample at 900 °C only resulted in a slight recovery of the GC structure. AFM and SEM analysis showed that the surface of the sample became rougher after Sr implantation. The roughness increased after the sample was annealed at 600 °C due to segregation of Sr towards the surface of the GC. SEM measurements of a sample with both implanted and un-implanted edges after annealing at 900 °C, showed that the high temperature heat treatment did not affect the surface topography of un-irradiated GC.

  7. Robust design optimization method for centrifugal impellers under surface roughness uncertainties due to blade fouling

    Science.gov (United States)

    Ju, Yaping; Zhang, Chuhua

    2016-03-01

    Blade fouling has been proved to be a great threat to compressor performance in operating stage. The current researches on fouling-induced performance degradations of centrifugal compressors are based mainly on simplified roughness models without taking into account the realistic factors such as spatial non-uniformity and randomness of the fouling-induced surface roughness. Moreover, little attention has been paid to the robust design optimization of centrifugal compressor impellers with considerations of blade fouling. In this paper, a multi-objective robust design optimization method is developed for centrifugal impellers under surface roughness uncertainties due to blade fouling. A three-dimensional surface roughness map is proposed to describe the nonuniformity and randomness of realistic fouling accumulations on blades. To lower computational cost in robust design optimization, the support vector regression (SVR) metamodel is combined with the Monte Carlo simulation (MCS) method to conduct the uncertainty analysis of fouled impeller performance. The analyzed results show that the critical fouled region associated with impeller performance degradations lies at the leading edge of blade tip. The SVR metamodel has been proved to be an efficient and accurate means in the detection of impeller performance variations caused by roughness uncertainties. After design optimization, the robust optimal design is found to be more efficient and less sensitive to fouling uncertainties while maintaining good impeller performance in the clean condition. This research proposes a systematic design optimization method for centrifugal compressors with considerations of blade fouling, providing a practical guidance to the design of advanced centrifugal compressors.

  8. The Current Status of the Japanese Penetrator Mission: LUNAR-A

    Science.gov (United States)

    Tanaka, S.; Shiraishi, H.; Fujimura, A.; Hayakawa, H.

    The scientific objective of the LUNAR-A, Japanese Penetrator Mission, is to explore the lunar interior by seismic and heat-flow experiments. Two penetrators containing two seismometers (horizontal and vertical components) and heat-flow probes will be deployed from a spacecraft onto the lunar surface, one on the nearside and the other on the farside of the moon. The final impact velocity of the penetrator will be about 300m/sec; it will encounter a shock of about 8000 G at impact on the lunar surface. According to numerous experimental impact tests using model penetrators and a lunar regolith analog target, each penetrator is predicted to penetrate to a depth of 1 to 3 m. The data obtained by the penetrators will be transmitted to the earth station via the LUNAR-A mother spacecraft orbiting at an altitude of about 200 km. The penetrator is a missile-shaped instrument carrier, which is about 14cm in diameter, 75cm in length, and about 14kg in weight without attitude control system. It contains a two-component seismometer and heat flow probes together with other supporting instruments such as a tilt meter and an accelerometer. The seismic observations are expected to provide key data on the size of the lunar core, as well as data on deep lunar mantle structure. The heat flow measurements at two penetrator deployment sites will also provide important data on the thermal structure and bulk concentrations of heat-generating elements in the Moon. These data will provide much stronger geophysical constraints on the origin and evolution of the Moon than has been obtained so far. The LUNAR-A spacecraft was supposed to be launched in the summer of 2004, but it was postponed due to the necessity of a replacement of the valves used in the RCS propulsion system of the spacecraft, following a recall issued by the manufacturer who found a malfunction of similar valves. Then, the technological review boards by ISAS and JAXA recommended that both the more robustness of the

  9. Real-Time Science Operations to Support a Lunar Polar Volatiles Rover Mission

    Science.gov (United States)

    Heldmann, Jennifer L.; Colaprete, Anthony; Elphic, Richard C.; Mattes, Greg; Ennico, Kimberly; Fritzler, Erin; Marinova, Margarita M.; McMurray, Robert; Morse, Stephanie; Roush, Ted L.; hide

    2014-01-01

    Future human exploration of the Moon will likely rely on in situ resource utilization (ISRU) to enable long duration lunar missions. Prior to utilizing ISRU on the Moon, the natural resources (in this case lunar volatiles) must be identified and characterized, and ISRU demonstrated on the lunar surface. To enable future uses of ISRU, NASA and the CSA are developing a lunar rover payload that can (1) locate near subsurface volatiles, (2) excavate and analyze samples of the volatile-bearing regolith, and (3) demonstrate the form, extractability and usefulness of the materials. Such investigations are important both for ISRU purposes and for understanding the scientific nature of these intriguing lunar volatile deposits. Temperature models and orbital data suggest near surface volatile concentrations may exist at briefly lit lunar polar locations outside persistently shadowed regions. A lunar rover could be remotely operated at some of these locations for the approx. 2-14 days of expected sunlight at relatively low cost. Due to the limited operational time available, both science and rover operations decisions must be made in real time, requiring immediate situational awareness, data analysis, and decision support tools. Given these constraints, such a mission requires a new concept of operations. In this paper we outline the results and lessons learned from an analog field campaign in July 2012 which tested operations for a lunar polar rover concept. A rover was operated in the analog environment of Hawaii by an off-site Flight Control Center, a rover navigation center in Canada, a Science Backroom at NASA Ames Research Center in California, and support teams at NASA Johnson Space Center in Texas and NASA Kennedy Space Center in Florida. We find that this type of mission requires highly efficient, real time, remotely operated rover operations to enable low cost, scientifically relevant exploration of the distribution and nature of lunar polar volatiles. The field

  10. Review of lunar telescope studies at MSFC

    Science.gov (United States)

    Hilchey, John D.; Nein, Max E.

    1993-09-01

    In the near future astronomers can take advantage of the lunar surface as the new 'high ground' from which to study the universe. Optical telescopes placed and operated on the lunar surface would be successors to NASA's Great Observatories. Four telescopes, ranging in aperture from a 16-m, IR/Vis/UV observatory down to a 1-m, UV 'transit' instrument, have been studied by the Lunar Telescope Working Group and the LUTE (lunar telescope ultraviolet experiment) Task Team of the Marshall Space Flight Center (MSFC). This paper presents conceptual designs of the telescopes, provides descriptions of the telescope subsystem options selected for each concept, and outlines the potential evolution of their science capabilities.

  11. Lunar architecture

    Science.gov (United States)

    Malek, Shahin

    The climatic conditions of Earth and human trends for discover the space, make these questions that how we can design a camp on the moon as a base for traveling in space or how we can live on that condition and what kind of camp we can have on the moon?!The first step in this way was creating the International Space Station on earth's orbit. (International Space Station, 2001) Settlement on moon was proposed since knowledge about it growth. Regarding to new technologies, architects parallel to engineers are trying to design and invent new ways for human settlement on moon because of its suitable conditions. Proposed habitats range from the actual spacecraft lander or their used fuel tanks, to inflatable modules of various shapes. Due to the researches until now, the first requirement for the living on other planets is water existence for human breath and fuel and after that we need to solve air pressure and gravity difference. (Colonization of the Moon, 2004) The Goal of this research is to answer to the question which is designing a camp on the Moon. But for this goal, there is need to think and study more about the subject and its factors. With qualitative and comparative methodology, the conditions of the Earth and the Moon will be comparing in different categories such as nature, human and design. I think that after water discovery, with using local materials and appropriate building design which can be on surface or underground, along with new sciences, we can plan for long period living on Moon. The important point is to consider Function, Form and Structure together in designing on the Moon. References: Colonization of the Moon. (2004). Retrieved December 14, 2009, from Wikipedia: http://en.wikipedia.org/wiki/Colonizationo ft heM oonStructure, InternationalSpaceStation.(2001).Retrie http : //en.wikipedia.org/wiki/InternationalS paceS tation

  12. Study of Plume Impingement Effects in the Lunar Lander Environment

    Science.gov (United States)

    Marichalar, Jeremiah; Prisbell, A.; Lumpkin, F.; LeBeau, G.

    2010-01-01

    Plume impingement effects from the descent and ascent engine firings of the Lunar Lander were analyzed in support of the Lunar Architecture Team under the Constellation Program. The descent stage analysis was performed to obtain shear and pressure forces on the lunar surface as well as velocity and density profiles in the flow field in an effort to understand lunar soil erosion and ejected soil impact damage which was analyzed as part of a separate study. A CFD/DSMC decoupled methodology was used with the Bird continuum breakdown parameter to distinguish the continuum flow from the rarefied flow. The ascent stage analysis was performed to ascertain the forces and moments acting on the Lunar Lander Ascent Module due to the firing of the main engine on take-off. The Reacting and Multiphase Program (RAMP) method of characteristics (MOC) code was used to model the continuum region of the nozzle plume, and the Direct Simulation Monte Carlo (DSMC) Analysis Code (DAC) was used to model the impingement results in the rarefied region. The ascent module (AM) was analyzed for various pitch and yaw rotations and for various heights in relation to the descent module (DM). For the ascent stage analysis, the plume inflow boundary was located near the nozzle exit plane in a region where the flow number density was large enough to make the DSMC solution computationally expensive. Therefore, a scaling coefficient was used to make the DSMC solution more computationally manageable. An analysis of the effectiveness of this scaling technique was performed by investigating various scaling parameters for a single height and rotation of the AM. Because the inflow boundary was near the nozzle exit plane, another analysis was performed investigating three different inflow contours to determine the effects of the flow expansion around the nozzle lip on the final plume impingement results.

  13. Walking Wheel Design for Lunar Rove-Rand and Its Application Simulation Based on Virtual Lunar Environment

    Directory of Open Access Journals (Sweden)

    Zhao Yibing

    2014-05-01

    Full Text Available The lunar rover design is the key problem of planet exploration. It is extraordinarily important for researchers to fully understand the lunar terrain and propose the reasonable lunar rover. In this paper, one new type of walking wheel modeled on impeller is presented based on vehicle terramechanics. The passive earth pressure of soil mechanics put forward by C. A. Coulomb is employed to obtain the wheel traction force. Some kinematics simulations are conducted for lunar rover model. Besides, this paper presents how to model lunar landing terrain containing typical statistic characteristic including craters and boulders; then, the second step is to construct basal lunar surface by using Brown Fractal Motion and the next is to add craters and boulders by means of known diameter algorithm and Random-create Diameter Algorithm. By means of importing 2D plain of lunar surface into UG, 3D parasolid is modeled and finally imported to ADAMS, which is available for lunar rover kinematics and dynamics simulation. Lastly, based on power spectrum curve of lunar terrain, the spectral characteristic of three different lunar terrain roughness is educed by using reverse engineering algorithm. Simulation results demonstrated the frequency of vibration mechanics properties of different roughness surfaces.

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

    Science.gov (United States)

    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.

  15. Lunar and Planetary Geology

    Science.gov (United States)

    Basilevsky, Alexander T.

    2018-05-01

    Lunar and planetary geology can be described using examples such as the geology of Earth (as the reference case) and geologies of the Earth's satellite the Moon; the planets Mercury, Mars and Venus; the satellite of Saturn Enceladus; the small stony asteroid Eros; and the nucleus of the comet 67P Churyumov-Gerasimenko. Each body considered is illustrated by its global view, with information given as to its position in the solar system, size, surface, environment including gravity acceleration and properties of its atmosphere if it is present, typical landforms and processes forming them, materials composing these landforms, information on internal structure of the body, stages of its geologic evolution in the form of stratigraphic scale, and estimates of the absolute ages of the stratigraphic units. Information about one body may be applied to another body and this, in particular, has led to the discovery of the existence of heavy "meteoritic" bombardment in the early history of the solar system, which should also significantly affect Earth. It has been shown that volcanism and large-scale tectonics may have not only been an internal source of energy in the form of radiogenic decay of potassium, uranium and thorium, but also an external source in the form of gravity tugging caused by attractions of the neighboring bodies. The knowledge gained by lunar and planetary geology is important for planning and managing space missions and for the practical exploration of other bodies of the solar system and establishing manned outposts on them.

  16. Characterizing the Lunar Particulate Atmosphere with the Autonomous Lunar Dust Observer (ALDO)

    Science.gov (United States)

    Grund, C. J.; Colwell, J. A.

    2008-07-01

    Photoelectric effects and solar wind charge the lunar surface, levitating particles. ALDO maps suspended dust in 3D using lidar. Phenomenology and instrument modeling, applications, projected performance and concepts of operation are discussed.

  17. Building an Economical and Sustainable Lunar Infrastructure to Enable Lunar Science and Space Commerce

    Science.gov (United States)

    Zuniga, Allison; Turner, Mark; Rasky, Dan

    2017-01-01

    A new concept study was initiated to examine the framework needed to gradually develop an economical and sustainable lunar infrastructure using a public private partnerships approach. This approach would establish partnership agreements between NASA and industry teams to develop cis-lunar and surface capabilities for mutual benefit while sharing cost and risk in the development phase and then allowing for transfer of operation of these infrastructure services back to its industry owners in the execution phase. These infrastructure services may include but are not limited to the following: lunar cargo transportation, power stations, energy storage devices, communication relay satellites, local communication towers, and surface mobility operations.

  18. Mechanical effects associated with surface loading of dry rock due to glaciation

    International Nuclear Information System (INIS)

    Wahi, K.K.; Hunter, R.L.

    1985-01-01

    Many scenarios of interest for a repository in the Pasco Basin begin with glaciation. Loading and unloading of joints and fractures due to the weight of ice sheets could affect the hydrologic properties of the host rock and surrounding units. Scoping calculations performed using two-dimensional numerical models with simplifying assumptions predict stress changes and uplift or subsidence caused by an advancing glacier. The magnitudes of surface uplift and subsidence predicted by the study agree well with previous independent predictions. Peak stress unloading near the repository horizon is a small fraction of the ambient stress. Any resultant aperture increase is likewise small. Based on the results of this study, mechanical loading caused by a glacier is expected to have a minimal effect on rock permeability, assuming that the excess compressive loads do not crush the rock. 13 refs., 3 figs., 1 tab

  19. International lunar observatory / power station: from Hawaii to the Moon

    Science.gov (United States)

    Durst, S.

    Astronomy's great advantages from the Moon are well known - stable surface, diffuse atmosphere, long cool nights (14 days), low gravity, far side radio frequency silence. A large variety of astronomical instruments and observations are possible - radio, optical and infrared telescopes and interferometers; interferometry for ultra- violet to sub -millimeter wavelengths and for very long baselines, including Earth- Moon VLBI; X-ray, gamma-ray, cosmic ray and neutrino detection; very low frequency radio observation; and more. Unparalleled advantages of lunar observatories for SETI, as well as for local surveillance, Earth observation, and detection of Earth approaching objects add significant utility to lunar astronomy's superlatives. At least nine major conferences in the USA since 1984 and many elsewhere, as well as ILEWG, IAF, IAA, LEDA and other organizations' astronomy-from-the-Moon research indicate a lunar observatory / power station, robotic at first, will be one of the first mission elements for a permanent lunar base. An international lunar observatory will be a transcending enterprise, highly principled, indispensable, soundly and broadly based, and far- seeing. Via Astra - From Hawaii to the Moon: The astronomy and scie nce communities, national space agencies and aerospace consortia, commercial travel and tourist enterprises and those aspiring to advance humanity's best qualities, such as Aloha, will recognize Hawaii in the 21st century as a new major support area and pan- Pacific port of embarkation to space, the Moon and beyond. Astronomical conditions and facilities on Hawaii's Mauna Kea provide experience for construction and operation of observatories on the Moon. Remote and centrally isolated, with diffuse atmosphere, sub-zero temperature and limited working mobility, the Mauna Kea complex atop the 4,206 meter summit of the largest mountain on the planet hosts the greatest collection of large astronomical telescopes on Earth. Lunar, extraterrestrial

  20. Astronaut Neil Armstrong participates in simulation of moon's surface

    Science.gov (United States)

    1969-01-01

    Astronaut Neil A. Armstrong, wearing an Extravehicular Mobility Unit, deploys a lunar surface television camera during lunar surface simulation training in bldg 9, Manned Spacecraft Center. Armstrong is the prime crew commander of the Apollo 11 lunar landing mission.

  1. Multi-state autonomous drilling for lunar exploration

    Directory of Open Access Journals (Sweden)

    Chen Chongbin

    2016-10-01

    Full Text Available Due to the lack of information of subsurface lunar regolith stratification which varies along depth, the drilling device may encounter lunar soil and lunar rock randomly in the drilling process. To meet the load safety requirements of unmanned sampling mission under limited orbital resources, the control strategy of autonomous drilling should adapt to the indeterminable lunar environments. Based on the analysis of two types of typical drilling media (i.e., lunar soil and lunar rock, this paper proposes a multi-state control strategy for autonomous lunar drilling. To represent the working circumstances in the lunar subsurface and reduce the complexity of the control algorithm, lunar drilling process was categorized into three drilling states: the interface detection, initiation of drilling parameters for recognition and drilling medium recognition. Support vector machine (SVM and continuous wavelet transform were employed for the online recognition of drilling media and interface, respectively. Finite state machine was utilized to control the transition among different drilling states. To verify the effectiveness of the multi-state control strategy, drilling experiments were implemented with multi-layered drilling media constructed by lunar soil simulant and lunar rock simulant. The results reveal that the multi-state control method is capable of detecting drilling state variation and adjusting drilling parameters timely under vibration interferences. The multi-state control method provides a feasible reference for the control of extraterrestrial autonomous drilling.

  2. Temperature dependent surface modification of molybdenum due to low energy He+ ion irradiation

    International Nuclear Information System (INIS)

    Tripathi, J.K.; Novakowski, T.J.; Joseph, G.; Linke, J.; Hassanein, A.

    2015-01-01

    In this paper, we report on the temperature dependent surface modifications in molybdenum (Mo) samples due to 100 eV He + ion irradiation in extreme conditions as a potential candidate to plasma-facing components in fusion devices alternative to tungsten. The Mo samples were irradiated at normal incidence, using an ion fluence of 2.6 × 10 24 ions m −2 (with a flux of 7.2 × 10 20 ions m −2 s −1 ). Surface modifications have been studied using high-resolution field emission scanning electron-(SEM) and atomic force (AFM) microscopy. At 773 K target temperature homogeneous evolution of molybdenum nanograins on the entire Mo surface were observed. However, at 823 K target temperature appearance of nano-pores and pin-holes nearby the grain boundaries, and Mo fuzz in patches were observed. The fuzz density increases significantly with target temperatures and continued until 973 K. However, at target temperatures beyond 973 K, counterintuitively, a sequential reduction in the fuzz density has been seen till 1073 K temperatures. At 1173 K and above temperatures, only molybdenum nano structures were observed. Our temperature dependent studies confirm a clear temperature widow, 823–1073 K, for Mo fuzz formation. Ex-situ high resolution X-ray photoelectron spectroscopy studies on Mo fuzzy samples show the evidence of MoO 3 3d doublets. This elucidates that almost all the Mo fuzz were oxidized during open air exposure and are thick enough as well. Likewise the microscopy studies, the optical reflectivity measurements also show a sequential reduction in the reflectivity values (i.e., enhancement in the fuzz density) up to 973 K and after then a sequential enhancement in the reflectivity values (i.e., reduction in the fuzz density) with target temperatures. This is in well agreement with microscopy studies where we observed clear temperature window for Mo fuzz growth

  3. Integrated lunar materials manufacturing process

    Science.gov (United States)

    Gibson, Michael A. (Inventor); Knudsen, Christian W. (Inventor)

    1990-01-01

    A manufacturing plant and process for production of oxygen on the moon uses lunar minerals as feed and a minimum of earth-imported, process materials. Lunar feed stocks are hydrogen-reducible minerals, ilmenite and lunar agglutinates occurring in numerous, explored locations mixed with other minerals in the pulverized surface layer of lunar soil known as regolith. Ilmenite (FeTiO.sub.3) and agglutinates contain ferrous (Fe.sup.+2) iron reducible by hydrogen to yield H.sub.2 O and metallic Fe at about 700.degree.-1,200.degree. C. The H.sub.2 O is electrolyzed in gas phase to yield H.sub.2 for recycle and O.sub.2 for storage and use. Hydrogen losses to lunar vacuum are minimized, with no net hydrogen (or any other earth-derived reagent) consumption except for small leaks. Feed minerals are surface-mined by front shovels and transported in trucks to the processing area. The machines are manned or robotic. Ilmenite and agglutinates occur mixed with silicate minerals which are not hydrogen-reducible at 700.degree.-1,200.degree. C. and consequently are separated and concentrated before feeding to the oxygen generation process. Solids rejected from the separation step and reduced solids from the oxygen process are returned to the mine area. The plant is powered by nuclear or solar power generators. Vapor-phase water electrolysis, a staged, countercurrent, fluidized bed reduction reactor and a radio-frequency-driven ceramic gas heater are used to improve thermal efficiency.

  4. Understanding the Lunar System Architecture Design Space

    Science.gov (United States)

    Arney, Dale C.; Wilhite, Alan W.; Reeves, David M.

    2013-01-01

    Based on the flexible path strategy and the desire of the international community, the lunar surface remains a destination for future human exploration. This paper explores options within the lunar system architecture design space, identifying performance requirements placed on the propulsive system that performs Earth departure within that architecture based on existing and/or near-term capabilities. The lander crew module and ascent stage propellant mass fraction are primary drivers for feasibility in multiple lander configurations. As the aggregation location moves further out of the lunar gravity well, the lunar lander is required to perform larger burns, increasing the sensitivity to these two factors. Adding an orbit transfer stage to a two-stage lunar lander and using a large storable stage for braking with a one-stage lunar lander enable higher aggregation locations than Low Lunar Orbit. Finally, while using larger vehicles enables a larger feasible design space, there are still feasible scenarios that use three launches of smaller vehicles.

  5. Our Lunar Destiny: Creating a Lunar Economy

    Science.gov (United States)

    Rohwer, Christopher J.

    2000-01-01

    "Our Lunar Destiny: Creating a Lunar Economy" supports a vision of people moving freely and economically between the earth and the Moon in an expansive space and lunar economy. It makes the economic case for the creation of a lunar space economy and projects the business plan that will make the venture an economic success. In addition, this paper argues that this vision can be created and sustained only by private enterprise and the legal right of private property in space and on the Moon. Finally, this paper advocates the use of lunar land grants as the key to unleashing the needed capital and the economic power of private enterprise in the creation of a 21st century lunar space economy. It is clear that the history of our United States economic system proves the value of private property rights in the creation of any new economy. It also teaches us that the successful development of new frontiers-those that provide economic opportunity for freedom-loving people-are frontiers that encourage, respect and protect the possession of private property and the fruits of labor and industry. Any new 21st century space and lunar economy should therefore be founded on this same principle.

  6. Isopleths of surface concentration and surface exposure rate due to a radioactive cloud released from a stack

    International Nuclear Information System (INIS)

    Kobayashi, Hideo; Yabuta, Hajimu; Katagiri, Hiroshi; Obata, Kazuichi; Kokubu, Morinobu

    1982-03-01

    Various calculations are made to estimate the distributions of concentration and γ-exposure rate due to a radioactive cloud released from a point source to the atmosphere. In this report, the isopleths of concentration and γ-exposure rate which were calculated are given in graphs to enable rapid prediction of the influence of released radioactive material in the emergency situation. Recently there are facilities which are equipped with a system to display the calculation results on CRT; but such practice is rather rare. By placing the calculated isopleths of reduction scale 1/25000 or 1/50000 on the usual map, any facilities without the CRT system can readily estimate the influence of an accidental release. The graphs of isopleths are given with the release height (11 values of 0 to 200 m at about 20 m intervals) and the atmospheric stability (6 classes) as parameters. Calculations of γ-exposure rates were made using the computer code GAMPUL developed by T. Hayashi and T. Shiraishi. In the calculation of radioactive concentrations and γ-exposure rates, the vertical diffusion depths, σsub(z), exceeding 1000 m are taken to be 1000 m according to the Meteorological Guide for the Safety Analysis of Power Reactor (J.AEC). The comparison between with and without this limitation in σsub(z) is made in the case of downwind axial surface distributions. (author)

  7. Calibration of VIIRS F1 Sensor Fire Detection Band Using lunar Observations

    Science.gov (United States)

    McIntire, Jeff; Efremova, Boryana; Xiong, Xiaoxiong

    2012-01-01

    Visible Infrared Imager Radiometer Suite (VIIRS) Fight 1 (Fl) sensor includes a fire detection band at roughly 4 microns. This spectral band has two gain states; fire detection occurs in the low gain state above approximately 345 K. The thermal bands normally utilize an on-board blackbody to provide on-orbit calibration. However, as the maximum temperature of this blackbody is 315 K, the low gain state of the 4 micron band cannot be calibrated in the same manner as the rest of the thermal bands. Regular observations of the moon provide an alternative calibration source. The lunar surface temperature has been recently mapped by the DIVINER sensor on the LRO platform. The periodic on-board high gain calibration along with the DIVINER surface temperatures was used to determine the emissivity and solar reflectance of the lunar surface at 4 microns; these factors and the lunar data are then used to fit the low gain calibration coefficients of the 4 micron band. Furthermore, the emissivity of the lunar surface is well known near 8.5 microns due to the Christiansen feature (an emissivity maximum associated with Si-O stretching vibrations) and the solar reflectance is negligible. Thus, the 8.5 micron band is used for relative calibration with the 4 micron band to de-trend any temporal variations. In addition, the remaining thermal bands are analyzed in a similar fashion, with both calculated emissivities and solar reflectances produced.

  8. Lunar Atmosphere Probe Station: A Proof-of-Concept Instrument Package for Monitoring the Lunar Atmosphere

    Science.gov (United States)

    Lazio, J.; Jones, D. L.; MacDowall, R. J.; Stewart, K. P.; Burns, J. O.; Farrell, W. M.; Giersch, L.; O'Dwyer, I. J.; Hicks, B. C.; Polisensky, E. J.; Hartman, J. M.; Nesnas, I.; Weiler, K.; Kasper, J. C.

    2013-12-01

    The lunar exosphere is the exemplar of a plasma near the surface of an airless body. Exposed to both the solar and interstellar radiation fields, the lunar exosphere is mostly ionized, and enduring questions regarding its properties include its density and vertical extent, the extent of contributions from volatile outgassing from the Moon, and its behavior over time, including response to the solar wind and modification by landers. Relative ionospheric measurements (riometry) are based on the simple physical principle that electromagnetic waves cannot propagate through a partially or fully ionized medium below the plasma frequency, and riometers have been deployed on the Earth in numerous remote and hostile environments. A multi-frequency riometer on the lunar surface would be able to monitor, *in situ*, the vertical extent of the lunar exosphere over time. We provide an update on a concept for a riometer implemented as a secondary science payload on future lunar landers, such as those recommended in the recent Planetary Sciences Decadal Survey report or commercial ventures. The instrument concept is simple, consisting of an antenna implemented as a metal deposited on polyimide film and receiver. We illustrate various deployment mechanisms and performance of a prototype in increasing lunar analog conditions. While the prime mission of such a riometer would be probing the lunar exosphere, our concept would also be capable to measuring the properties of dust impactors. The Lunar University Network for Astrophysical Research consortium is funded by the NASA Lunar Science Institute to investigate concepts for astrophysical observatories on the Moon. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. Artist's impression of the Lunar Atmosphere Probe Station.

  9. Active Solid State Dosimetry for Lunar EVA

    Science.gov (United States)

    Wrbanek, John D.; Fralick, Gustave C.; Wrbanek, Susan Y.; Chen, Liang-Yu.

    2006-01-01

    The primary threat to astronauts from space radiation is high-energy charged particles, such as electrons, protons, alpha and heavier particles, originating from galactic cosmic radiation (GCR), solar particle events (SPEs) and trapped radiation belts in Earth orbit. There is also the added threat of secondary neutrons generated as the space radiation interacts with atmosphere, soil and structural materials.[1] For Lunar exploration missions, the habitats and transfer vehicles are expected to provide shielding from standard background radiation. Unfortunately, the Lunar Extravehicular Activity (EVA) suit is not expected to afford such shielding. Astronauts need to be aware of potentially hazardous conditions in their immediate area on EVA before a health and hardware risk arises. These conditions would include fluctuations of the local radiation field due to changes in the space radiation field and unknown variations in the local surface composition. Should undue exposure occur, knowledge of the dynamic intensity conditions during the exposure will allow more precise diagnostic assessment of the potential health risk to the exposed individual.[2

  10. Lunar Science from and for Planet Earth

    Science.gov (United States)

    Pieters, M. C.; Hiesinger, H.; Head, J. W., III

    2008-09-01

    Our Moon Every person on Earth is familiar with the Moon. Every resident with nominal eyesight on each continent has seen this near-by planetary body with their own eyes countless times. Those fortunate enough to have binoculars or access to a telescope have explored the craters, valleys, domes, and plains across the lunar surface as changing lighting conditions highlight the mysteries of this marvellously foreign landscape. Schoolchildren learn that the daily rhythm and flow of tides along the coastlines of our oceans are due to the interaction of the Earth and the Moon. This continuous direct and personal link is but one of the many reasons lunar science is fundamental to humanity. The Earth-Moon System In the context of space exploration, our understanding of the Earth-Moon system has grown enormously. The Moon has become the cornerstone for most aspects of planetary science that relate to the terrestrial (rocky) planets. The scientific context for exploration of the Moon is presented in a recent report by a subcommittee of the Space Studies Board of the National Research Council [free from the website: http://books.nap.edu/catalog.php?record_id=11954]. Figure 1 captures the interwoven themes surrounding lunar science recognized and discussed in that report. In particular, it is now recognized that the Earth and the Moon have been intimately linked in their early history. Although they subsequently took very different evolutionary paths, the Moon provides a unique and valuable window both into processes that occurred during the first 600 Million years of solar system evolution (planetary differentiation and the heavy bombardment record) as well as the (ultimately dangerous) impact record of more recent times. This additional role of the Moon as keystone is because the Earth and the Moon share the same environment at 1 AU, but only the Moon retains a continuous record of cosmic events. An Initial Bloom of Exploration and Drought The space age celebrated its 50th

  11. Lunar Penetrating Radar onboard the Chang'e-3 mission

    Science.gov (United States)

    Fang, Guang-You; Zhou, Bin; Ji, Yi-Cai; Zhang, Qun-Ying; Shen, Shao-Xiang; Li, Yu-Xi; Guan, Hong-Fei; Tang, Chuan-Jun; Gao, Yun-Ze; Lu, Wei; Ye, Sheng-Bo; Han, Hai-Dong; Zheng, Jin; Wang, Shu-Zhi

    2014-12-01

    Lunar Penetrating Radar (LPR) is one of the important scientific instruments onboard the Chang'e-3 spacecraft. Its scientific goals are the mapping of lunar regolith and detection of subsurface geologic structures. This paper describes the goals of the mission, as well as the basic principles, design, composition and achievements of the LPR. Finally, experiments on a glacier and the lunar surface are analyzed.

  12. Development of a Compact, Deep-Penetrating Heat Flow Instrument for Lunar Landers: In-Situ Thermal Conductivity System

    Science.gov (United States)

    Nagihara, S.; Zacny, K.; Hedlund, M.; Taylor, P. T.

    2012-01-01

    Geothermal heat flow is obtained as a product of the geothermal gradient and the thermal conductivity of the vertical soil/rock/regolith interval penetrated by the instrument. Heat flow measurements are a high priority for the geophysical network missions to the Moon recommended by the latest Decadal Survey and previously the International Lunar Network. One of the difficulties associated with lunar heat flow measurement on a robotic mission is that it requires excavation of a relatively deep (approx 3 m) hole in order to avoid the long-term temporal changes in lunar surface thermal environment affecting the subsurface temperature measurements. Such changes may be due to the 18.6-year-cylcle lunar precession, or may be initiated by presence of the lander itself. Therefore, a key science requirement for heat flow instruments for future lunar missions is to penetrate 3 m into the regolith and to measure both thermal gradient and thermal conductivity. Engineering requirements are that the instrument itself has minimal impact on the subsurface thermal regime and that it must be a low-mass and low-power system like any other science instrumentation on planetary landers. It would be very difficult to meet the engineering requirements, if the instrument utilizes a long (> 3 m) probe driven into the ground by a rotary or percussive drill. Here we report progress in our efforts to develop a new, compact lunar heat flow instrumentation that meets all of these science and engineering requirements.

  13. Strength and compressibility of returned lunar soil.

    Science.gov (United States)

    Carrier, W. D., III; Bromwell, L. G.; Martin, R. T.

    1972-01-01

    Two oedometer and three direct shear tests have been performed in vacuum on a 200 g sample of lunar soil from Apollo 12 (12001, 119). The compressibility data have been used to calculate bulk density and shear wave velocity versus depth on the lunar surface. The shear wave velocity was found to increase approximately with the one-fourth power of the depth, and the results suggest that the Apollo 14 Active Seismic Experiment may not have detected the Fra Mauro formation at a depth of 8.5 m, but only naturally consolidated lunar soil. The shear data indicate that the strength of the lunar soil sample is about 65% that of a ground basalt simulant at the same void ratio.

  14. Measurement of the lunar neutron density profile

    International Nuclear Information System (INIS)

    Woolum, D.S.; Burnett, D.S.; Furst, M.; Weiss, J.R.

    1975-01-01

    An in situ measurement of the lunar neutron density from 20 to 400 g cm -2 depth below the lunar surface was made by the Apollo 17 Lunar Neutron Probe Experiment (LNPE) using particle tracks produced by the 10 B (n,α) 7 Li reaction. Both the absolute magnitude and the depth profile of the neutron density are in good agreement with theoretical calculations by Lingenfelter, Canfield, and Hampel. However, relatively small deviations between experiment and theory in the effect of Cd absorption on the neutron density and in the relative 149 Sm to 157 Gd capture rates reported previously (Russ et al., 1972) imply that the true lunar 157 Gd capture rate is about one half of that calculated theoretically. (Auth.)

  15. Pressurized Lunar Rover (PLR)

    Science.gov (United States)

    Creel, Kenneth; Frampton, Jeffrey; Honaker, David; McClure, Kerry; Zeinali, Mazyar; Bhardwaj, Manoj; Bulsara, Vatsal; Kokan, David; Shariff, Shaun; Svarverud, Eric

    The objective of this project was to design a manned pressurized lunar rover (PLR) for long-range transportation and for exploration of the lunar surface. The vehicle must be capable of operating on a 14-day mission, traveling within a radius of 500 km during a lunar day or within a 50-km radius during a lunar night. The vehicle must accommodate a nominal crew of four, support two 28-hour EVA's, and in case of emergency, support a crew of six when near the lunar base. A nominal speed of ten km/hr and capability of towing a trailer with a mass of two mt are required. Two preliminary designs have been developed by two independent student teams. The PLR 1 design proposes a seven meter long cylindrical main vehicle and a trailer which houses the power and heat rejection systems. The main vehicle carries the astronauts, life support systems, navigation and communication systems, lighting, robotic arms, tools, and equipment for exploratory experiments. The rover uses a simple mobility system with six wheels on the main vehicle and two on the trailer. The nonpressurized trailer contains a modular radioisotope thermoelectric generator (RTG) supplying 6.5 kW continuous power. A secondary energy storage for short-term peak power needs is provided by a bank of lithium-sulfur dioxide batteries. The life support system is partly a regenerative system with air and hygiene water being recycled. A layer of water inside the composite shell surrounds the command center allowing the center to be used as a safe haven during solar flares. The PLR 1 has a total mass of 6197 kg. It has a top speed of 18 km/hr and is capable of towing three metric tons, in addition to the RTG trailer. The PLR 2 configuration consists of two four-meter diameter, cylindrical hulls which are passively connected by a flexible passageway, resulting in the overall vehicle length of 11 m. The vehicle is driven by eight independently suspended wheels. The dual-cylinder concept allows articulated as well as double

  16. Lunar dust transport and potential interactions with power system components

    International Nuclear Information System (INIS)

    Katzan, C.M.; Edwards, J.L.

    1991-11-01

    The lunar surface is covered by a thick blanket of fine dust. This dust may be readily suspended from the surface and transported by a variety of mechanisms. As a consequence, lunar dust can accumulate on sensitive power components, such as photovoltaic arrays and radiator surfaces, reducing their performance. In addition to natural mechanisms, human activities on the Moon will disturb significant amounts of lunar dust. Of all the mechanisms identified, the most serious is rocket launch and landing. The return of components from the Surveyor III provided a rare opportunity to observe the effects of the nearby landing of the Apollo 12 lunar module. The evidence proved that significant dust accumulation occurred on the Surveyor at a distance of 155 m. From available information on particle suspension and transport mechanisms, a series of models was developed to predict dust accumulation as a function of distance from the lunar module. The accumulation distribution was extrapolated to a future lunar lander scenario. These models indicate that accumulation is expected to be substantial even as far as 2 km from the landing site. Estimates of the performance penalties associated with lunar dust coverage on radiators and photovoltaic arrays are presented. Because of the lunar dust adhesive and cohesive properties, the most practical dust defensive strategy appears to be the protection of sensitive components from the arrival of lunar dust by location, orientation, or barriers

  17. Lunar dust transport and potential interactions with power system components

    Energy Technology Data Exchange (ETDEWEB)

    Katzan, C.M.; Edwards, J.L.

    1991-11-01

    The lunar surface is covered by a thick blanket of fine dust. This dust may be readily suspended from the surface and transported by a variety of mechanisms. As a consequence, lunar dust can accumulate on sensitive power components, such as photovoltaic arrays and radiator surfaces, reducing their performance. In addition to natural mechanisms, human activities on the Moon will disturb significant amounts of lunar dust. Of all the mechanisms identified, the most serious is rocket launch and landing. The return of components from the Surveyor III provided a rare opportunity to observe the effects of the nearby landing of the Apollo 12 lunar module. The evidence proved that significant dust accumulation occurred on the Surveyor at a distance of 155 m. From available information on particle suspension and transport mechanisms, a series of models was developed to predict dust accumulation as a function of distance from the lunar module. The accumulation distribution was extrapolated to a future lunar lander scenario. These models indicate that accumulation is expected to be substantial even as far as 2 km from the landing site. Estimates of the performance penalties associated with lunar dust coverage on radiators and photovoltaic arrays are presented. Because of the lunar dust adhesive and cohesive properties, the most practical dust defensive strategy appears to be the protection of sensitive components from the arrival of lunar dust by location, orientation, or barriers.

  18. Erosive Wear Characterization of Materials for Lunar Construction

    Science.gov (United States)

    Mpagazehe, Jeremiah N.; Street, Kenneth W., Jr.; Delgado, Irebert R.; Higgs, C. Fred, III

    2012-01-01

    NASA s Apollo missions revealed that exhaust from the retrorockets of landing spacecraft may act to significantly accelerate lunar dust on the surface of the Moon. A recent study by Immer et al. (C. Immer, P.T. Metzger, P.E. Hintze, A. Nick, and R. Horan, Apollo 12 Lunar Module exhaust plume impingement on Lunar Surveyor III, Icarus, Vol. 211, pp. 1089-1102, 2011) investigated coupons returned to Earth from the Surveyor III lunar probe which were subjected to lunar dust impingement by the Apollo 12 Lunar Module landing. Their study revealed that even with indirect impingement, the spacecraft sustained erosive damage from the fast-moving lunar dust particles. In this work, results are presented from a series of erosive wear experiments performed on 6061 Aluminum using the JSC-1AF lunar dust simulant. Optical profilometry was used to investigate the surface after the erosion process. It was found that even short durations of lunar dust simulant impacting at low velocities produced substantial changes in the surface.

  19. Magnetic Sorting of the Regolith on the Moon: Lunar Swirls

    Science.gov (United States)

    Pieters, C. M.; Garrick-Bethell, I.; Hemingway, D.

    2014-12-01

    All of the mysterious albedo features on the Moon called "lunar swirls" are associated with magnetic anomalies, but not all magnetic anomalies are associated with lunar swirls [1]. It is often hypothesized that the albedo markings are tied to immature regolith on the surface, perhaps due to magnetic shielding of the solar wind and prevention of normal space weathering of the soil. Although interaction of the solar wind with the surface at swirls is indeed affected by the local magnetic field [2], this does not appear to result in immature soils on the surface. Calibrated spectra from the Moon Mineralogy Mapper [M3] (in image format) demonstrate that the high albedo markings for swirls are simply not consistent with immature regolith as is now understood from detailed analyses of lunar samples [eg 3]. However, M3 data show that the high albedo features of swirls are distinct and quite different from normal soils (in both the highlands and the mare). They allexhibit a flatter continuum across the near-infrared, but the actual band strength of ferrous minerals shows little (if any) deviation [4]. Recent analyses of magnetic field direction at swirls [5] mimic the observed albedo patterns (horizontal surface fields in bright areas, vertical surface fields in dark lanes). When coupled with the optical properties of magnetic separates of lunar soils [6] and our knowledge that the magnetic component of the soil results from space weathering [3,6], we propose a new and very simple explanation for these enigmatic albedo markings: the lunar swirls result from magnetic sorting of a well developed regolith. With time, normal gardening of the soil over a magnetic anomaly causes some of the dark magnetic component of the soil to be gradually removed from regions (high albedo areas) and accumulated in others (dark lanes). We are modeling predicted sorting rates using realistic rates of dust production. If this mechanism is tenable, only the origin of these magnetic anomalies

  20. Orbital studies of lunar magnetism

    Science.gov (United States)

    Mcleod, M. G.; Coleman, P. J., Jr.

    1982-01-01

    Limitations of present lunar magnetic maps are considered. Optimal processing of satellite derived magnetic anomaly data is also considered. Studies of coastal and core geomagnetism are discussed. Lunar remanent and induced lunar magnetization are included.

  1. Electrodynamic Dust Shield for Lunar/ISS Experiment

    Data.gov (United States)

    National Aeronautics and Space Administration — The Electrostatics and Surface Physics Laboratory at Kennedy Space Center is developing a dust mitigation experiment and testing it on the lunar surface and on the...

  2. Perspectives on Lunar Helium-3

    Science.gov (United States)

    Schmitt, Harrison H.

    1999-01-01

    Global demand for energy will likely increase by a factor of six or eight by the mid-point of the 21st Century due to a combination of population increase, new energy intensive technologies, and aspirations for improved standards of living in the less-developed world (1). Lunar helium-3 (3He), with a resource base in the Tranquillitatis titanium-rich lunar maria (2,3) of at least 10,000 tonnes (4), represents one potential energy source to meet this rapidly escalating demand. The energy equivalent value of 3He delivered to operating fusion power plants on Earth would be about 3 billion per tonne relative to today's coal which supplies most of the approximately 90 billion domestic electrical power market (5). These numbers illustrate the magnitude of the business opportunity. The results from the Lunar Prospector neutron spectrometer (6) suggests that 3He also may be concentrated at the lunar poles along with solar wind hydrogen (7). Mining, extraction, processing, and transportation of helium to Earth requires new innovations in engineering but no known new engineering concepts (1). By-products of lunar 3He extraction, largely hydrogen, oxygen, and water, have large potential markets in space and ultimately will add to the economic attractiveness of this business opportunity (5). Inertial electrostatic confinement (IEC) fusion technology appears to be the most attractive and least capital intensive approach to terrestrial fusion power plants (8). Heavy lift launch costs comprise the largest cost uncertainty facing initial business planning, however, many factors, particularly long term production contracts, promise to lower these costs into the range of 1-2000 per kilogram versus about 70,000 per kilogram fully burdened for the Apollo Saturn V rocket (1). A private enterprise approach to developing lunar 3He and terrestrial IEC fusion power would be the most expeditious means of realizing this unique opportunity (9). In spite of the large, long-term potential

  3. Lunar plant biology--a review of the Apollo era.

    Science.gov (United States)

    Ferl, Robert J; Paul, Anna-Lisa

    2010-04-01

    Recent plans for human return to the Moon have significantly elevated scientific interest in the lunar environment with emphasis on the science to be done in preparation for the return and while on the lunar surface. Since the return to the Moon is envisioned as a dedicated and potentially longer-term commitment to lunar exploration, questions of the lunar environment and particularly its impact on biology and biological systems have become a significant part of the lunar science discussion. Plants are integral to the discussion of biology on the Moon. Plants are envisioned as important components of advanced habitats and fundamental components of advanced life-support systems. Moreover, plants are sophisticated multicellular eukaryotic life-forms with highly orchestrated developmental processes, well-characterized signal transduction pathways, and exceedingly fine-tuned responses to their environments. Therefore, plants represent key test organisms for understanding the biological impact of the lunar environment on terrestrial life-forms. Indeed, plants were among the initial and primary organisms that were exposed to returned lunar regolith from the Apollo lunar missions. This review discusses the original experiments involving plants in association with the Apollo samples, with the intent of understanding those studies within the context of the first lunar exploration program and drawing from those experiments the data to inform the studies critical within the next lunar exploration science agenda.

  4. Lunar and interplanetary trajectories

    CERN Document Server

    Biesbroek, Robin

    2016-01-01

    This book provides readers with a clear description of the types of lunar and interplanetary trajectories, and how they influence satellite-system design. The description follows an engineering rather than a mathematical approach and includes many examples of lunar trajectories, based on real missions. It helps readers gain an understanding of the driving subsystems of interplanetary and lunar satellites. The tables and graphs showing features of trajectories make the book easy to understand. .

  5. Lunar Radio Telescopes: A Staged Approach for Lunar Science, Heliophysics, Astrobiology, Cosmology, and Exploration

    Science.gov (United States)

    Lazio, Joseph; Bowman, Judd D.; Burns, Jack O.; Farrell, W. M.; Jones, D. L.; Kasper, J. C.; MacDowall, R. J.; Stewart, K. P.; Weiler, K.

    2012-01-01

    Observations with radio telescopes address key problems in cosmology, astrobiology, heliophysics, and planetary science including the first light in the Universe (Cosmic Dawn), magnetic fields of extrasolar planets, particle acceleration mechanisms, and the lunar ionosphere. The Moon is a unique science platform because it allows access to radio frequencies that do not penetrate the Earth's ionosphere and because its far side is shielded from intense terrestrial emissions. The instrument packages and infrastructure needed for radio telescopes can be transported and deployed as part of Exploration activities, and the resulting science measurements may inform Exploration (e.g., measurements of lunar surface charging). An illustrative roadmap for the staged deployment of lunar radio telescopes

  6. Surface erosion of fusion reactor components due to radiation blistering and neutron sputtering

    International Nuclear Information System (INIS)

    Das, S.K.; Kaminsky, M.

    1975-01-01

    Radiation blistering and neutron sputtering can lead to the surface erosion of fusion reactor components exposed to plasma radiations. Recent studies of methods to reduce the surface erosion caused by these processes are discussed

  7. Cis-Lunar Base Camp

    Science.gov (United States)

    Merrill, Raymond G.; Goodliff, Kandyce E.; Mazanek, Daniel D.; Reeves, John D., Jr.

    2012-01-01

    Historically, when mounting expeditions into uncharted territories, explorers have established strategically positioned base camps to pre-position required equipment and consumables. These base camps are secure, safe positions from which expeditions can depart when conditions are favorable, at which technology and operations can be tested and validated, and facilitate timely access to more robust facilities in the event of an emergency. For human exploration missions into deep space, cis-lunar space is well suited to serve as such a base camp. The outer regions of cis-lunar space, such as the Earth-Moon Lagrange points, lie near the edge of Earth s gravity well, allowing equipment and consumables to be aggregated with easy access to deep space and to the lunar surface, as well as more distant destinations, such as near-Earth Asteroids (NEAs) and Mars and its moons. Several approaches to utilizing a cis-lunar base camp for sustainable human exploration, as well as some possible future applications are identified. The primary objective of the analysis presented in this paper is to identify options, show the macro trends, and provide information that can be used as a basis for more detailed mission development. Compared within are the high-level performance and cost of 15 preliminary cis-lunar exploration campaigns that establish the capability to conduct crewed missions of up to one year in duration, and then aggregate mass in cis-lunar space to facilitate an expedition from Cis-Lunar Base Camp. Launch vehicles, chemical propulsion stages, and electric propulsion stages are discussed and parametric sizing values are used to create architectures of in-space transportation elements that extend the existing in-space supply chain to cis-lunar space. The transportation options to cis-lunar space assessed vary in efficiency by almost 50%; from 0.16 to 0.68 kg of cargo in cis-lunar space for every kilogram of mass in Low Earth Orbit (LEO). For the 15 cases, 5-year campaign

  8. Lunar Soil Erosion Physics for Landing Rockets on the Moon

    Science.gov (United States)

    Clegg, Ryan N.; Metzger, Philip T.; Huff, Stephen; Roberson, Luke B.

    2008-01-01

    To develop a lunar outpost, we must understand the blowing of soil during launch and landing of the new Altair Lander. For example, the Apollo 12 Lunar Module landed approximately 165 meters from the deactivated Surveyor Ill spacecraft, scouring its surfaces and creating numerous tiny pits. Based on simulations and video analysis from the Apollo missions, blowing lunar soil particles have velocities up to 2000 m/s at low ejection angles relative to the horizon, reach an apogee higher than the orbiting Command and Service Module, and travel nearly the circumference of the Moon [1-3]. The low ejection angle and high velocity are concerns for the lunar outpost.

  9. Lunar Reconnaissance Orbiter Lunar Workshops for Educators

    Science.gov (United States)

    Jones, A. P.; Hsu, B. C.; Hessen, K.; Bleacher, L.

    2012-12-01

    The Lunar Workshops for Educators (LWEs) are a series of weeklong professional development workshops, accompanied by quarterly follow-up sessions, designed to educate and inspire grade 6-12 science teachers, sponsored by the Lunar Reconnaissance Orbiter (LRO). Participants learn about lunar science and exploration, gain tools to help address common student misconceptions about the Moon, find out about the latest research results from LRO scientists, work with data from LRO and other lunar missions, and learn how to bring these data to their students using hands-on activities aligned with grade 6-12 National Science Education Standards and Benchmarks and through authentic research experiences. LWEs are held around the country, primarily in locations underserved with respect to NASA workshops. Where possible, workshops also include tours of science facilities or field trips intended to help participants better understand mission operations or geologic processes relevant to the Moon. Scientist and engineer involvement is a central tenant of the LWEs. LRO scientists and engineers, as well as scientists working on other lunar missions, present their research or activities to the workshop participants and answer questions about lunar science and exploration. This interaction with the scientists and engineers is consistently ranked by the LWE participants as one of the most interesting and inspiring components of the workshops. Evaluation results from the 2010 and 2011 workshops, as well as preliminary analysis of survey responses from 2012 participants, demonstrated an improved understanding of lunar science concepts among LWE participants in post-workshop assessments (as compared to identical pre-assessments) and a greater understanding of how to access and effectively share LRO data with students. Teachers reported increased confidence in helping students conduct research using lunar data, and learned about programs that would allow their students to make authentic

  10. Estimation of Apollo lunar dust transport using optical extinction measurements

    OpenAIRE

    Lane, John E.; Metzger, Philip T.

    2015-01-01

    A technique to estimate mass erosion rate of surface soil during landing of the Apollo Lunar Module (LM) and total mass ejected due to the rocket plume interaction is proposed and tested. The erosion rate is proportional to the product of the second moment of the lofted particle size distribution N(D), and third moment of the normalized soil size distribution S(D), divided by the integral of S(D)D^2/v(D), where D is particle diameter and v(D) is the vertical component of particle velocity. Th...

  11. On a lunar space elevator

    Science.gov (United States)

    Lemke, E. H.

    We consider a space elevator system for lunar surface access that consists of a space station in circumlunar orbit, a cable reaching down to some meters above the surface and a magnetically levitated vehicle driven by a linear motor. It accelerates the load to be lifted to the speed of the cable end. Loads to be delivered are either put on the vehicle and slowed down by it or they are slowed down by a sand braking technique in a mare terrain. It is technically possible to operate this transport system nearly without fuel supply from Earth. We calculate various steel cable dimensions for a static stress maximum of 1/5th of the tensile strength. The process of takeover is considered in detail. Five ways of eliminating the adverse large cable elongation due to the load are described. The touchdown process and behaviour of the cable after disconnection are analysed. The positive difference between the speed of the load at takeover and cable end can excite a large inplane swing motion. We propose to damp it by a dissipative pulley that hangs in a loop of wire leading to the ends of two beams mounted on the space station tangentially to the orbit, the pulley's core being connected with the load. Roll librations are damped by energy losses in the elastic beams; damping can be reinforced by viscous beam elements and/or controlled out-of-plane motions of the beams. We argue in favour of the possibility of fast deployment. The problems of vehicle vibrations and agglutination at sand braking blades are underlined and their combined experimental investigation is suggested.

  12. Sound velocity and compressibility for lunar rocks 17 and 46 and for glass spheres from the lunar soil.

    Science.gov (United States)

    Schreiber, E; Anderson, O L; Sogat, N; Warren, N; Scholz, C

    1970-01-30

    Four experiments on lunar materials are reported: (i) resonance on glass spheres from the soil; (ii) compressibility of rock 10017; (iii) sound velocities of rocks 10046 and 10017; (iv) sound velocity of the lunar fines. The data overlap and are mutually consistent. The glass beads and rock 10017 have mechanical properties which correspond to terrestrial materials. Results of (iv) are consistent with low seismic travel times in the lunar maria. Results of analysis of the microbreccia (10046) agreed with the soil during the first pressure cycle, but after overpressure the rock changed, and it then resembled rock 10017. Three models of the lunar surface were constructed giving density and velocity profiles.

  13. Overview of lunar detection of ultra-high energy particles and new plans for the SKA

    NARCIS (Netherlands)

    James, Clancy W.; Alvarez-Muñiz, Jaime; Bray, Justin D.; Buitink, Stijn; Dagkesamanskii, Rustam D.; Ekers, Ronald D.; Falcke, Heino; Gayley, Ken; Huege, Tim; Mevius, Maaijke; Mutel, Rob; Scholten, Olaf; Spencer, Ralph; ter Veen, Sander; Winchen, Tobias

    2017-01-01

    The lunar technique is a method for maximising the collection area for ultra-high-energy (UHE) cosmic ray and neutrino searches. The method uses either ground-based radio telescopes or lunar orbiters to search for Askaryan emission from particles cascading near the lunar surface. While experiments

  14. Apollo 12, A New Vista for Lunar Science.

    Science.gov (United States)

    National Aeronautics and Space Administration, Washington, DC.

    Man's second lunar landing, Apollo 12, provided a wealth of scientific information about the moon. The deployment of the magnetometer, seismometer, and ionosphere detector, and other activities on the lunar surface are described. A number of color photographs show the astronauts setting up equipment on the moon as well as close-ups of the lunar…

  15. Moonraker and Tetris: Japanese Microrovers for Lunar Cave Exploration

    Science.gov (United States)

    Yoshida, K.; Britton, N.; Walker, J.; Shimizu, T.; Tanaka, T.; Hakamada, T.

    2015-10-01

    A Japanese team HAKUTO is developing a robotic system for exploration of Lunar lava tubes. Motivated by Google Lunar XPRIZE that requires 500 m travel on any surface of Moon, but the team plans to go down into a skylight in Lacus Mortis.

  16. Amplification of Surface-Enhanced Raman Scattering Due to Substrate-Mediated Localized Surface Plasmons in Gold Nanodimers

    KAUST Repository

    Yue, Weisheng; Wang, Zhihong; Whittaker, John; Lopez-royo, Francisco; Yang, Yang; Zayats, Anatoly

    2017-01-01

    that significant improvement in a SERS signal can be achieved with substrates combining localized surface plasmon resonances and a nonresonant plasmonic substrate. By introducing a continuous gold (Au) film underneath Au nanodimers antenna arrays, an over 10-fold

  17. CERN-derived analysis of lunar radiation backgrounds

    Science.gov (United States)

    Wilson, Thomas L.; Svoboda, Robert

    1993-01-01

    The Moon produces radiation which background-limits scientific experiments there. Early analyses of these backgrounds have either failed to take into consideration the effect of charm in particle physics (because they pre-dated its discovery), or have used branching ratios which are no longer strictly valid (due to new accelerator data). We are presently investigating an analytical program for deriving muon and neutrino spectra generated by the Moon, converting an existing CERN computer program known as GEANT which does the same for the Earth. In so doing, this will (1) determine an accurate prompt neutrino spectrum produced by the lunar surface; (2) determine the lunar subsurface particle flux; (3) determine the consequence of charm production physics upon the lunar background radiation environment; and (4) provide an analytical tool for the NASA astrophysics community with which to begin an assessment of the Moon as a scientific laboratory versus its particle radiation environment. This will be done on a recurring basis with the latest experimental results of the particle data groups at Earth-based high-energy accelerators, in particular with the latest branching ratios for charmed meson decay. This will be accomplished for the first time as a full 3-dimensional simulation.

  18. Estimation of Apollo Lunar Dust Transport using Optical Extinction Measurements

    Science.gov (United States)

    Lane, John E.; Metzger, Philip T.

    2015-04-01

    A technique to estimate mass erosion rate of surface soil during landing of the Apollo Lunar Module (LM) and total mass ejected due to the rocket plume interaction is proposed and tested. The erosion rate is proportional to the product of the second moment of the lofted particle size distribution N(D), and third moment of the normalized soil size distribution S(D), divided by the integral of S(D)ṡD2/v(D), where D is particle diameter and v(D) is the vertical component of particle velocity. The second moment of N(D) is estimated by optical extinction analysis of the Apollo cockpit video. Because of the similarity between mass erosion rate of soil as measured by optical extinction and rainfall rate as measured by radar reflectivity, traditional NWS radar/rainfall correlation methodology can be applied to the lunar soil case where various S(D) models are assumed corresponding to specific lunar sites.

  19. Hydrogen generation due to water splitting on Si - terminated 4H-Sic(0001) surfaces

    Science.gov (United States)

    Li, Qingfang; Li, Qiqi; Yang, Cuihong; Rao, Weifeng

    2018-02-01

    The chemical reactions of hydrogen gas generation via water splitting on Si-terminated 4H-SiC surfaces with or without C/Si vacancies were studied by using first-principles. We studied the reaction mechanisms of hydrogen generation on the 4H-SiC(0001) surface. Our calculations demonstrate that there are major rearrangements in surface when H2O approaches the SiC(0001) surface. The first H splitting from water can occur with ground-state electronic structures. The second H splitting involves an energy barrier of 0.65 eV. However, the energy barrier for two H atoms desorbing from the Si-face and forming H2 gas is 3.04 eV. In addition, it is found that C and Si vacancies can form easier in SiC(0001)surfaces than in SiC bulk and nanoribbons. The C/Si vacancies introduced can enhance photocatalytic activities. It is easier to split OH on SiC(0001) surface with vacancies compared to the case of clean SiC surface. H2 can form on the 4H-SiC(0001) surface with C and Si vacancies if the energy barriers of 1.02 and 2.28 eV are surmounted, respectively. Therefore, SiC(0001) surface with C vacancy has potential applications in photocatalytic water-splitting.

  20. Reactions of atmospheric vapors with lunar soil

    International Nuclear Information System (INIS)

    Fuller, E.L. Jr.; Agron, P.A.

    1976-03-01

    Detailed experimental data have been acquired for the hydration of the surfaces of lunar fines. Inert vapor adsorption has been employed to measure the surface properties (surface energy, surface area, porosity, etc.) and changes wrought in the hydration-dehydration processes. Plausible mechanisms have been considered and the predominant process involves hydration of the metamict metallosilicate surfaces to form a hydrated laminar structure akin to terrestrial clays. Additional credence for this interpretation is obtained by comparison to existing geochemical literature concerning terrestrial weathering of primary metallosilicates. The surface properties of the hydrated lunar fines are compared favorably to those of terrestrial clay minerals. In addition, experimental results are given to show that fresh disordered surfaces of volcanic sand react with water vapor in a manner virtually identical to the majority of the lunar fines. The results show that ion track etching and/or grain boundary attack are minor contributions in the weathering of lunar fines in the realm of our microgravimetric experimental conditions. 14 references

  1. Investigation the effects of metallic substrate surfaces due to ion-plasma treatment

    International Nuclear Information System (INIS)

    Shulaev, V.M.; Taran, V.S.; Timoshenko, A.I.; Gasilin, V.V.

    2011-01-01

    It has been found correlation between modification effects and duration of ion-plasma cleaning the substrate surface with titanium ions. Experiments were carried out using serial vacuum-arc equipment ''Bulat-6'' at the stationary mode in non-filtered titanium plasma, which contained considerable quantity of evaporated material droplets. The polished cylinder substrates (diameter and height 9,14,20 mm) have been treated. The substrates were manufactured of stainless steel 12X18H10T and non-oxygen copper M00b. The substrates surface roughness after ion-plasma treatment has been investigated with electron microscope JEOL JSM-840 and optic interference non-contact profilograph- profilometer ''Micron-alpha''. According obtained results the surface of copper and stainless steel substrates has been treated to intensive modification, i.e. substrate surface after treatment significantly differs from initial one. During final ion-plasma treatment a number of effects occur: purification from surface oxides is accompanied with metallic surface ''contamination'' by the cathode material macrodroplets, surface micromelting accompanied by roughness increase, the surface layer annealing with noticeable decrease of hardness.

  2. Time-dependent inversion of surface subsidence due to dynamic reservoir compaction

    NARCIS (Netherlands)

    Muntendam-Bos, A.G.; Kroon, I.C.; Fokker, P.A.

    2008-01-01

    We introduce a novel, time-dependent inversion scheme for resolving temporal reservoir pressure drop from surface subsidence observations (from leveling or GPS data, InSAR, tiltmeter monitoring) in a single procedure. The theory is able to accommodate both the absence of surface subsidence estimates

  3. Influence of random roughness on the adhesion between metal surfaces due to capillary condensation

    NARCIS (Netherlands)

    van Zwol, P. J.; Palasantzas, G.; De Hosson, J. Th. M.

    2007-01-01

    The capillary force was measured by atomic force microscopy between a gold coated sphere mounted on a cantilever and gold surfaces with different roughnesses. For smooth surfaces the capillary adhesive force surpasses in magnitude any dispersion, e.g., van der Waals/Casimir and/or electrostatic

  4. Far-Ultraviolet Characteristics of Lunar Swirls

    Science.gov (United States)

    Hendrix, A. R.; Greathouse, T. K.; Retherford, K. D.; Mandt, K. E.; Gladstone, G. R.; Kaufmann, D. E.; Hurley, D. M.; Feldman, P. D.; Pryor, W. R.; Bullock, M. A.; Stern, S. A.

    2015-10-01

    Lunar swirls are often described as bright sinuous regions of the Moon that appear to be relatively immature -i.e. less space-weathered than surrounding regions. Swirls are mysterious but seem to be linked to the interaction between the solar wind and the lunar magnetic anomalies (e.g., [1]). Commonly-studied swirls include Mare Ingenii (in a mare- highlands boundary region), Reiner Gamma (in a mare region), and Gerasimovich (in a highlands region). Swirls are known to be surface features: they have no expression at radar depths [2], exhibit no topography, and craters on swirls that penetrate the bright surface terrain reveal underlying dark material [3].

  5. Lunar-A

    Indian Academy of Sciences (India)

    penetrators will be transmitted to the earth station via the Lunar-A mother spacecraft orbiting at an altitude of about .... to save the power consumption of the Lunar-A penetrator .... and an origin-time versus tidal-phases correlation. (Toksoz et al ...

  6. The ESA Lunar Lander and the search for Lunar Volatiles

    Science.gov (United States)

    Morse, A. D.; Barber, S. J.; Pillinger, J. M.; Sheridan, S.; Wright, I. P.; Gibson, E. K.; Merrifield, J. A.; Waltham, N. R.; Waugh, L. J.; Pillinger, C. T.

    2011-10-01

    Following the Apollo era the moon was considered a volatile poor body. Samples collected from the Apollo missions contained only ppm levels of water formed by the interaction of the solar wind with the lunar regolith [1]. However more recent orbiter observations have indicated that water may exist as water ice in cold polar regions buried within craters at concentrations of a few wt. % [2]. Infrared images from M3 on Chandrayaan-1 have been interpreted as showing the presence of hydrated surface minerals with the ongoing hydroxyl/water process feeding cold polar traps. This has been supported by observation of ephemeral features termed "space dew" [3]. Meanwhile laboratory studies indicate that water could be present in appreciable quantities in lunar rocks [4] and could also have a cometary source [5]. The presence of sufficient quantities of volatiles could provide a resource which would simplify logistics for long term lunar missions. The European Space Agency (ESA's Directorate of Human Spaceflight and Operations) have provisionally scheduled a robotic mission to demonstrate key technologies to enable later human exploration. Planned for launch in 2018, the primary aim is for precise automated landing, with hazard avoidance, in zones which are almost constantly illuminated (e.g. at the edge of the Shackleton crater at the lunar south pole). These regions would enable the solar powered Lander to survive for long periods > 6 months, but require accurate navigation to within 200m. Although landing in an illuminated area, these regions are close to permanently shadowed volatile rich regions and the analysis of volatiles is a major science objective of the mission. The straw man payload includes provision for a Lunar Volatile and Resources Analysis Package (LVRAP). The authors have been commissioned by ESA to conduct an evaluation of possible technologies to be included in L-VRAP which can be included within the Lander payload. Scientific aims are to demonstrate the

  7. Prediction of residual stress distributions due to surface machining and welding and crack growth simulation under residual stress distribution

    International Nuclear Information System (INIS)

    Ihara, Ryohei; Katsuyama, JInya; Onizawa, Kunio; Hashimoto, Tadafumi; Mikami, Yoshiki; Mochizuki, Masahito

    2011-01-01

    Research highlights: → Residual stress distributions due to welding and machining are evaluated by XRD and FEM. → Residual stress due to machining shows higher tensile stress than welding near the surface. → Crack growth analysis is performed using calculated residual stress. → Crack growth result is affected machining rather than welding. → Machining is an important factor for crack growth. - Abstract: In nuclear power plants, stress corrosion cracking (SCC) has been observed near the weld zone of the core shroud and primary loop recirculation (PLR) pipes made of low-carbon austenitic stainless steel Type 316L. The joining process of pipes usually includes surface machining and welding. Both processes induce residual stresses, and residual stresses are thus important factors in the occurrence and propagation of SCC. In this study, the finite element method (FEM) was used to estimate residual stress distributions generated by butt welding and surface machining. The thermoelastic-plastic analysis was performed for the welding simulation, and the thermo-mechanical coupled analysis based on the Johnson-Cook material model was performed for the surface machining simulation. In addition, a crack growth analysis based on the stress intensity factor (SIF) calculation was performed using the calculated residual stress distributions that are generated by welding and surface machining. The surface machining analysis showed that tensile residual stress due to surface machining only exists approximately 0.2 mm from the machined surface, and the surface residual stress increases with cutting speed. The crack growth analysis showed that the crack depth is affected by both surface machining and welding, and the crack length is more affected by surface machining than by welding.

  8. Lunar Lava Tube Sensing

    Science.gov (United States)

    York, Cheryl Lynn; Walden, Bryce; Billings, Thomas L.; Reeder, P. Douglas

    1992-01-01

    Large (greater than 300 m diameter) lava tube caverns appear to exist on the Moon and could provide substantial safety and cost benefits for lunar bases. Over 40 m of basalt and regolith constitute the lava tube roof and would protect both construction and operations. Constant temperatures of -20 C reduce thermal stress on structures and machines. Base designs need not incorporate heavy shielding, so lightweight materials can be used and construction can be expedited. Identification and characterization of lava tube caverns can be incorporated into current precursor lunar mission plans. Some searches can even be done from Earth. Specific recommendations for lunar lava tube search and exploration are (1) an Earth-based radar interferometer, (2) an Earth-penetrating radar (EPR) orbiter, (3) kinetic penetrators for lunar lava tube confirmation, (4) a 'Moon Bat' hovering rocket vehicle, and (5) the use of other proposed landers and orbiters to help find lunar lava tubes.

  9. Lunar Global Heat Flow: Predictions and Constraints

    Science.gov (United States)

    Siegler, M.; Williams, J. P.; Paige, D. A.; Feng, J.

    2017-12-01

    The global thermal state of the Moon provides fundamental information on its bulk composition and interior evolution. The Moon is known to have a highly asymmetric surface composition [e.g. Lawrence et al., 2003] and crustal thickness [Wieczorek et al.,2012], which is suspected to result from interior asymmetries [Wieczorek and Phillips, 2000; Laneuville et al., 2013]. This is likely to cause a highly asymmetric surface heat flux, both past and present. Our understanding the thermal evolution and composition of the bulk moon therefore requires a global picture of the present lunar thermal state, well beyond our two-point Apollo era measurement. As on the on the Earth, heat flow measurements need to be taken in carefully selected locations to truly characterize the state of the planet's interior. Future surface heat flux and seismic observations will be affected by the presence of interior temperature and crustal radiogenic anomalies, so placement of such instruments is critically important for understanding the lunar interior. The unfortunate coincidence that Apollo geophysical measurements lie areas within or directly abutting the highly radiogenic, anomalously thin-crusted Procellarum region highlights the importance of location for in situ geophysical study [e.g. Siegler and Smrekar, 2014]. Here we present the results of new models of global lunar geothermal heat flux. We synthesize data from several recent missions to constrain lunar crustal composition, thickness and density to provide global predictions of the surface heat flux of the Moon. We also discuss implications from new surface heat flux constraints from the LRO Diviner Lunar Radiometer Experiment and Chang'E 2 Microwave Radiometer. We will identify areas with the highest uncertainty to provide insight on the placement of future landed geophysical missions, such as the proposed Lunar Geophysical Network, to better aim our future exploration of the Moon.

  10. Albumin receptor effect may be due to a surface-induced conformational change in albumin

    International Nuclear Information System (INIS)

    Reed, R.G.; Burrington, C.M.

    1989-01-01

    To determine whether equilibrium binding between albumin and hepatocytes involves a cell surface receptor for albumin, we incubated freshly isolated rat hepatocytes with 125 I-albumin and determined the amount of albumin associated with the cells as a function of the total albumin concentration. The resulting two-phase binding curve showed the rat albumin-hepatocyte interaction to consist of a saturable binding interaction with a dissociation constant of 1.1 microM and 2 X 10(6) sites/cell in addition to a weak, nonsaturable binding interaction. However, the saturable binding of albumin to hepatocytes did not appear to result from the presence of an albumin receptor on the cell surface; the interaction was the same for different species of albumin, for chemically modified albumins, and for fragments of albumin representing mutually exclusive domains of the molecule. The saturable binding was, instead, found to involve a subpopulation of albumin with an enhanced affinity for the cell surface. We show that this subpopulation of albumin is generated upon contact with either solid surfaces or cell surfaces and can be transferred from one surface to another. We propose that the two-phase Scatchard binding curve and the ''albumin receptor effect'' reflect two populations of albumin that bind to the cell surface with different affinities rather than one population of albumin that binds to two classes of binding sites

  11. Pavement service life extension due to asphalt surface treatment interlayer : research project capsule.

    Science.gov (United States)

    2016-07-01

    The Louisiana Department of Transportation and Development (DOTD) has been : using asphalt surface treatment (AST) interlayers over soil cement base courses : as a means to mitigate shrinkage cracks from reflecting through the asphaltic : concrete (A...

  12. Irreversible particle motion in surfactant-laden interfaces due to pressure-dependent surface viscosity

    Science.gov (United States)

    Manikantan, Harishankar; Squires, Todd M.

    2017-09-01

    The surface shear viscosity of an insoluble surfactant monolayer often depends strongly on its surface pressure. Here, we show that a particle moving within a bounded monolayer breaks the kinematic reversibility of low-Reynolds-number flows. The Lorentz reciprocal theorem allows such irreversibilities to be computed without solving the full nonlinear equations, giving the leading-order contribution of surface pressure-dependent surface viscosity. In particular, we show that a disc translating or rotating near an interfacial boundary experiences a force in the direction perpendicular to that boundary. In unbounded monolayers, coupled modes of motion can also lead to non-intuitive trajectories, which we illustrate using an interfacial analogue of the Magnus effect. This perturbative approach can be extended to more complex geometries, and to two-dimensional suspensions more generally.

  13. Influence of random roughness on the adhesion between metal surfaces due to capillary condensation

    OpenAIRE

    van Zwol, P. J.; Palasantzas, G.; De Hosson, J. Th. M.

    2007-01-01

    The capillary force was measured by atomic force microscopy between a gold coated sphere mounted on a cantilever and gold surfaces with different roughnesses. For smooth surfaces the capillary adhesive force surpasses in magnitude any dispersion, e.g., van der Waals/Casimir and/or electrostatic forces. A substantial decrease in the capillary force was observed by increasing the roughness ampltitude a few nanometers in the range of 1-10 nm. From these measurements two limits can be defined: a ...

  14. Resistivity scaling due to electron surface scattering in thin metal layers

    Science.gov (United States)

    Zhou, Tianji; Gall, Daniel

    2018-04-01

    The effect of electron surface scattering on the thickness-dependent electrical resistivity ρ of thin metal layers is investigated using nonequilibrium Green's function density functional transport simulations. Cu(001) thin films with thickness d =1 -2 nm are used as a model system, employing a random one-monolayer-high surface roughness and frozen phonons to cause surface and bulk scattering, respectively. The zero-temperature resistivity increases from 9.7 ±1.0 μ Ω cm at d =1.99 nm to 18.7 ±2.6 μ Ω cm at d =0.9 0 nm, contradicting the asymptotic T =0 prediction from the classical Fuchs-Sondheimer model. At T =9 00 K, ρ =5.8 ±0.1 μ Ω cm for bulk Cu and ρ =13.4 ±1.1 and 22.5 ±2.4 μ Ω cm for layers with d =1.99 and 0.90 nm, respectively, indicating an approximately additive phonon contribution which, however, is smaller than for bulk Cu or atomically smooth layers. The overall data indicate that the resistivity contribution from surface scattering is temperature-independent and proportional to 1 /d , suggesting that it can be described using a surface-scattering mean-free path λs for 2D transport which is channel-independent and proportional to d . Data fitting indicates λs=4 ×d for the particular simulated Cu(001) surfaces with a one-monolayer-high surface roughness. The 1 /d dependence deviates considerably from previous 1 /d2 predictions from quantum models, indicating that the small-roughness approximation in these models is not applicable to very thin (<2 nm) layers, where the surface roughness is a considerable fraction of d .

  15. Energy and Momentum Relaxation Times of 2D Electrons Due to Near Surface Deformation Potential Scattering

    Science.gov (United States)

    Pipa, Viktor; Vasko, Fedor; Mitin, Vladimir

    1997-03-01

    The low temperature energy and momentum relaxation rates of 2D electron gas placed near the free or clamped surface of a semi-infinit sample are calculated. To describe the electron-acoustic phonon interaction with allowance of the surface effect the method of elasticity theory Green functions was used. This method allows to take into account the reflection of acoustic waves from the surface and related mutual conversion of LA and TA waves. It is shown that the strength of the deformation potential scattering at low temperatures substantially depends on the mechanical conditions at the surface: relaxation rates are suppressed for the free surface while for the rigid one the rates are enhanced. The dependence of the conductivity on the distance between the 2D layer and the surface is discussed. The effect is most pronounced in the range of temperatures 2 sl pF < T < (2 hbar s_l)/d, where pF is the Fermi momentum, sl is the velocity of LA waves, d is the width of the quantum well.

  16. The Microstructure of Lunar Micrometeorite Impact Craters

    Science.gov (United States)

    Noble, S. K.; Keller, L. P.; Christoffersen, R.; Rahman, Z.

    2016-01-01

    The peak of the mass flux of impactors striking the lunar surface is made up of objects approximately 200 micrometers in diameter that erode rocks, comminute regolith grains, and produce agglutinates. The effects of these micro-scale impacts are still not fully understood. Much effort has focused on evaluating the physical and optical effects of micrometeorite impacts on lunar and meteoritic material using pulsed lasers to simulate the energy deposited into a substrate in a typical hypervelocity impact. Here we characterize the physical and chemical changes that accompany natural micrometeorite impacts into lunar rocks with long surface exposure to the space environment (12075 and 76015). Transmission electron microscope (TEM) observations were obtained from cross-sections of approximately 10-20 micrometers diameter craters that revealed important micro-structural details of micrometeorite impact processes, including the creation of npFe (sup 0) in the melt, and extensive deformation around the impact site.

  17. Surface behaviour of first-wall materials due to the synergistic effect of helium and hydrogen isotopes

    International Nuclear Information System (INIS)

    Abramov, E.; Moreno, D.; Solovioff, G.; Eliezer, D.

    1994-01-01

    Scanning electron microscopy has been used to investigate changes in surface morphology due to helium implantation and hydrogen charging. Pure polycrystalline nickel, OFHC copper and Cu-1.8Be-0.2Co (CAD 172) alloy have been studied. The influence of helium implantation parameters on blister formation and growth was investigated. Hydrogen charging (cathodic or thermal-gas) was found to lower the helium content needed for blistering and surface exfoliation. The effect of heating, carried out after hydrogen charging, was also studied. For the copper samples, hydrogen damage was produced by oxide reduction at the oxide-metal interface. This damage was found to be lower when the sputtering due to helium implantation increased. The CuBe alloy showed a greater hydrogen resistance due to the stability of the surface BeO. ((orig.))

  18. Amplification of Surface-Enhanced Raman Scattering Due to Substrate-Mediated Localized Surface Plasmons in Gold Nanodimers

    KAUST Repository

    Yue, Weisheng

    2017-03-28

    Surface-enhanced Raman scattering (SERS) is ubiquitous in chemical and biochemical sensing, imaging and identification. Maximizing SERS enhancement is a continuous effort focused on the design of appropriate SERS substrates. Here we show that significant improvement in a SERS signal can be achieved with substrates combining localized surface plasmon resonances and a nonresonant plasmonic substrate. By introducing a continuous gold (Au) film underneath Au nanodimers antenna arrays, an over 10-fold increase in SERS enhancement is demonstrated. Triangular, rectangle and disc dimers were studied, with bowtie antenna providing highest SERS enhancement. Simulations of electromagnetic field distributions of the Au nanodimers on the Au film support the observed enhancement dependences. The hybridization of localized plasmonic modes with the image modes in a metal film provides a straightforward way to improve SERS enhancement in designer SERS substrate.

  19. Inhalation Toxicity of Ground Lunar Dust Prepared from Apollo-14 Soil

    Science.gov (United States)

    James, John T.; Lam, Chiu-wing; Scully, Robert R.; Cooper, Bonnie L.

    2011-01-01

    Within the decade one or more space-faring nations intend to return humans to the moon for more in depth exploration of the lunar surface and subsurface than was conducted during the Apollo days. The lunar surface is blanketed with fine dust, much of it in the respirable size range (<10 micron). Eventually, there is likely to be a habitable base and rovers available to reach distant targets for sample acquisition. Despite designs that could minimize the entry of dust into habitats and rovers, it is reasonable to expect lunar dust to pollute both as operations progress. Apollo astronauts were exposed briefly to dust at nuisance levels, but stays of up to 6 months on the lunar surface are envisioned. Will repeated episodic exposures to lunar dust present a health hazard to those engaged in lunar exploration? Using rats exposed to lunar dust by nose-only inhalation, we set out to investigate that question.

  20. Failure of Cleaning Verification in Pharmaceutical Industry Due to Uncleanliness of Stainless Steel Surface.

    Science.gov (United States)

    Haidar Ahmad, Imad A; Blasko, Andrei

    2017-08-11

    The aim of this work is to identify the parameters that affect the recovery of pharmaceutical residues from the surface of stainless steel coupons. A series of factors were assessed, including drug product spike levels, spiking procedure, drug-excipient ratios, analyst-to-analyst variability, intraday variability, and cleaning procedure of the coupons. The lack of a well-defined procedure that consistently cleaned the coupon surface was identified as the major contributor to low and variable recoveries. Assessment of cleaning the surface of the coupons with clean-in-place solutions (CIP) gave high recovery (>90%) and reproducible results (Srel≤4%) regardless of the conditions that were assessed previously. The approach was successfully applied for cleaning verification of small molecules (MW <1,000 Da) as well as large biomolecules (MW up to 50,000 Da).

  1. The Chameleon Effect: characterization challenges due to the variability of nanoparticles and their surfaces of nanoparticles and their surfaces

    Science.gov (United States)

    Baer, Donald R.

    2018-05-01

    Nanoparticles in a variety of forms are increasing important in fundamental research, technological and medical applications, and environmental or toxicology studies. Physical and chemical drivers that lead to multiple types of particle instabilities complicate both the ability to produce, appropriately characterize, and consistently deliver well-defined particles, frequently leading to inconsistencies and conflicts in the published literature. This perspective suggests that provenance information, beyond that often recorded or reported, and application of a set of core characterization methods, including a surface sensitive technique, consistently applied at critical times can serve as tools in the effort minimize reproducibility issues.

  2. Lunar Water Resource Demonstration

    Science.gov (United States)

    Muscatello, Anthony C.

    2008-01-01

    In cooperation with the Canadian Space Agency, the Northern Centre for Advanced Technology, Inc., the Carnegie-Mellon University, JPL, and NEPTEC, NASA has undertaken the In-Situ Resource Utilization (ISRU) project called RESOLVE. This project is a ground demonstration of a system that would be sent to explore permanently shadowed polar lunar craters, drill into the regolith, determine what volatiles are present, and quantify them in addition to recovering oxygen by hydrogen reduction. The Lunar Prospector has determined these craters contain enhanced hydrogen concentrations averaging about 0.1%. If the hydrogen is in the form of water, the water concentration would be around 1%, which would translate into billions of tons of water on the Moon, a tremendous resource. The Lunar Water Resource Demonstration (LWRD) is a part of RESOLVE designed to capture lunar water and hydrogen and quantify them as a backup to gas chromatography analysis. This presentation will briefly review the design of LWRD and some of the results of testing the subsystem. RESOLVE is to be integrated with the Scarab rover from CMIJ and the whole system demonstrated on Mauna Kea on Hawaii in November 2008. The implications of lunar water for Mars exploration are two-fold: 1) RESOLVE and LWRD could be used in a similar fashion on Mars to locate and quantify water resources, and 2) electrolysis of lunar water could provide large amounts of liquid oxygen in LEO, leading to lower costs for travel to Mars, in addition to being very useful at lunar outposts.

  3. The design procedures on brick building against surface ground deformations due to mining and earthquake

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, J.; Yang, S. (China University of Mining and Technology (China))

    1992-05-01

    By analysing the effects of ground motion and deformation on surface buildings, and drawing on the experience of damages caused by the Tangshan and Chenhai earthquakes, the authors discuss the design of brick and concrete buildings which are protected against the damaging effects of both earthquakes and mining activities. 5 figs.

  4. Quantum critical fluctuations due to nested Fermi surface: The case of spinless fermions

    International Nuclear Information System (INIS)

    Schlottmann, P.

    2007-01-01

    A quantum critical point (QCP) can be obtained by tuning the critical temperature of a second-order phase transition to zero. A simple model of spinless fermions with nested Fermi surface leading to a charge density wave is considered. The QCP is obtained by tuning the nesting mismatch of the Fermi surface, which has the following consequences: (i) For the tuned QCP, the specific heat over T and the effective mass increase with the logarithm of the temperature as T is lowered. (ii) For the tuned QCP the linewidth of the quasi-particles is sublinear in T and ω. (iii) The specific heat and the linewidth display a crossover from non-Fermi liquid (∼T) to Fermi liquid (∼T 2 ) behavior with increasing nesting mismatch and decreasing temperature. (iv) For the tuned QCP, the dynamical charge susceptibility has a quasi-elastic peak with a linewidth proportional to T. (v) For non-critical Fermi vector mismatch the peak is inelastic. (vi) While the specific heat and the quasi-particle linewidth are only weakly dependent on the geometry of the nested Fermi surfaces, the momentum-dependent dynamical susceptibility is expected to be affected by the shape of the Fermi surface

  5. Lunar Gene Bank for Endangered Species

    Science.gov (United States)

    Swain, Ramakrushna

    2016-07-01

    Introduction: Before the dawn of the 22nd century, we face the huge risk of losing our genetic heritage accumulated during aeons of evolution. The losses include hundreds of vertebrates, human gene pools, hundreds of thousands of plants and over a million insect species. As we have observed, adequate conservation of habitat is unfeasible and active breeding programs cover only a handful of the many thousand species threatened. We propose cryopreservation of germplasms by constructing a cDNA library based gene bank for endangered species in the permanently shadowed polar lunar craters that would provide immunity from both natural disadvantages and humanitarian intrusions. Rationale: Under such alarming circumstances, we turned to cryopreservation as an option but over thousands of years economic depression, sabotage, conflicts, warfare or even a brief disruption to the precise cryopreservation can hamper the storage of genetic samples.When we are considering conservation it is always preferable to go for a more secure and permanent solution. It was found out that the climatic and strategic location of the lunar polar craters are adequately hospitable, remote and free of maintenance and human observation as they provide naturally cryogenic temperature, reduced gravity and vacuum environment, non-reactive surface, safety from celestial intrusion and permanent shadow which doesn't allow the temperature to fluctuate thus providing most suitable storage facilities for the germplasms. PSRs provide steady temperature of 40- 60K and immunity to earthquakes due to low seismic activity. At these sites, burial in one meter or more of the regolith will provide protection against the solar wind, solar and galactic cosmic rays and micrometeorite impact. It provides the minimum necessary barrier from human intervention and at the same time enables easy retrieval for future usage. Genetic samples of endangered species can enable restoration even after its extinction. Preserved

  6. Accumulation and circulation of gaseous radon between lunar fines

    International Nuclear Information System (INIS)

    Lambert, G.; Bristeau, P.; CEA Centre d'Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette; Le Roulley, J.C.

    1975-01-01

    During the lunar night, the temperature of the regolith upper layer is lower than the radon freezing point. Thus radon atoms coming from the interior can be trapped at the surface of the cold lunar fines. The 222 Rn daughter products, 210 Pb and 210 Po, are embedded in a very thin layer at the surface of the grains. It is therefore possible, by spectrometry, to distinguish between the continuum due to uranium, thorium (and decay products) homogeneously distributed and the narrow peak at 5.3MeV, due to an excess of 210 Pb. The mean day-and-night concentration was about 3.5x10 3 atoms of intergranular 222 Rn per g of superficial fines, corresponding to a continuous flow of 3 atoms per minute and per cm 2 of soil. To account for such a flow of radon atoms moving in a random walk from a 6 meter source depth, the pore size of the regolith should be 60μ. On the other hand, the involved changes in the isotopic composition of the radiogenic lead remain less than 1% [fr

  7. Changes in extreme regional sea surface height due to an abrupt weakening of the Atlantic meridional overturning circulation

    NARCIS (Netherlands)

    Brunnabend, S.-E.; Dijkstra, H. A.; Kliphuis, M. A.; van Werkhoven, B.J.C.; Bal, H. E.; Seinstra, F.; Maassen, J.; van Meersbergen, M.

    2014-01-01

    As an extreme scenario of dynamical sea level changes, regional sea surface height (SSH) changes that occur in the North Atlantic due to an abrupt weakening of the Atlantic meridional overturning circulation (AMOC) are simulated. Two versions of the same ocean-only model are used to study the effect

  8. A novel lunar bed rest analogue.

    Science.gov (United States)

    Cavanagh, Peter R; Rice, Andrea J; Licata, Angelo A; Kuklis, Matthew M; Novotny, Sara C; Genc, Kerim O; Englehaupt, Ricki K; Hanson, Andrea M

    2013-11-01

    Humans will eventually return to the Moon and thus there is a need for a ground-based analogue to enable the study of physiological adaptations to lunar gravity. An important unanswered question is whether or not living on the lunar surface will provide adequate loading of the musculoskeletal system to prevent or attenuate the bone loss that is seen in microgravity. Previous simulations have involved tilting subjects to an approximately 9.5 degrees angle to achieve a lunar gravity component parallel to the long-axis of the body. However, subjects in these earlier simulations were not weight-bearing, and thus these protocols did not provide an analogue for load on the musculoskeletal system. We present a novel analogue which includes the capability to simulate standing and sitting in a lunar loading environment. A bed oriented at a 9.5 degrees angle was mounted on six linear bearings and was free to travel with one degree of freedom along rails. This allowed approximately 1/6 body weight loading of the feet during standing. "Lunar" sitting was also successfully simulated. A feasibility study demonstrated that the analogue was tolerated by subjects for 6 d of continuous bed rest and that the reaction forces at the feet during periods of standing were a reasonable simulation of lunar standing. During the 6 d, mean change in the volume of the quadriceps muscles was -1.6% +/- 1.7%. The proposed analogue would appear to be an acceptable simulation of lunar gravity and deserves further exploration in studies of longer duration.

  9. Prediction of abrupt reservoir compaction and surface subsidence due to pore collapse in carbonates

    Energy Technology Data Exchange (ETDEWEB)

    Smits, R.M.M.; de Waal, A.; van Kooten, J.F.C.

    1986-01-01

    A new procedure has been developed to predict the abrupt in-situ compaction and the associated surface subsidence above high-porosity carbonate fields showing pore collapse. The approach is based on an extensive laboratory compaction study in which the effects of carbonate type, porosity, core preparation, pore saturant, horizontal to vertical stress ratio and loading rate on the pore collapse behaviour were investigated. For each carbonate type a trendline was established describing the relationship between the porosity after collapse and the vertical effective stress. This trendline concept, in combination with existing subsidence models, enables reservoir compaction and surface subsidence to be predicted on the basis of wireline porosity logs. Static and dynamic elastic constants were found to be uncorrelated during pore collapse. The position of the trendline depends strongly on carbonate type, pore saturant, loading rate and stress ratio. Therefore procedures are given to derive the correct in-situ trendline from laboratory compaction experiments.

  10. Simulation of surface profile formation in oxygen laser cutting of mild steel due to combustion cycles

    Energy Technology Data Exchange (ETDEWEB)

    Ermolaev, G V; Kovalev, O B [Khristianovich Institute of Theoretical and Applied Mechanics, Siberian Branch of Russian Academy of Sciences, Institutskaya Str 4/1, Novosibirsk, 630090 (Russian Federation)

    2009-09-21

    A physicomathematical model of cyclic iron combustion in an oxygen flow during oxygen laser cutting of metal sheets is developed. The combustion front is set into motion by focused laser radiation and a heterogeneous oxidation reaction in oxygen. The burning rate is limited by oxygen supply from the gas phase towards the metal surface, and the interface motion depends on the local temperature. A 3D numerical simulation predicts wavy structures on the metal surface; their linear sizes depend on the scanning speed of the laser beam, the thickness of the produced liquid oxide film and the parameters of the oxygen jet flow. Simulation results help in understanding the mechanism of striation formation during oxygen gas-laser cutting of mild steel and are in qualitative agreement with experimental findings.

  11. Enhancement of the thermo-optical response of silver nanoparticles due to surface plasmon resonance

    Science.gov (United States)

    Hashemi Zadeh, Sakineh; Rashidi-Huyeh, Majid; Palpant, Bruno

    2017-10-01

    Owing to their remarkable optical properties, noble metals' nanoparticles are proposed for many applications. Controlling the temperature dependence of these properties may then appear to be of great relevance. In this paper, we investigate the thermo-optical properties of silver nanoparticles. Different silver nanocolloids were prepared with different surface plasmon resonance modes. The thermo-extinction spectra of the colloidal solutions were then evaluated by measuring the extinction spectra at different temperatures. This reveals a typical peak-valley profile around each surface plasmon resonance mode. Mie theory was used to study theoretically the impact of nanoparticle size on the thermo-optical properties. The results allow us to interpret properly the experimental findings.

  12. Rupture Dynamics along Thrust Dipping Fault: Inertia Effects due to Free Surface Wave Interactions

    Science.gov (United States)

    Vilotte, J. P.; Scala, A.; Festa, G.

    2017-12-01

    We numerically investigate the dynamic interaction between free surface and up-dip, in-plane rupture propagation along thrust faults, under linear slip-weakening friction. With reference to shallow along-dip rupture propagation during large subduction earthquakes, we consider here low dip-angle fault configurations with fixed strength excess and depth-increasing initial stress. In this configuration, the rupture undergoes a break of symmetry with slip-induced normal stress perturbations triggered by the interaction with reflected waves from the free surface. We found that both body-waves - behind the crack front - and surface waves - at the crack front - can trigger inertial effects. When waves interact with the rupture before this latter reaches its asymptotic speed, the rupture can accelerate toward the asymptotic speed faster than in the unbounded symmetric case, as a result of these inertial effects. Moreover, wave interaction at the crack front also affects the slip rate generating large ground motion on the hanging wall. Imposing the same initial normal stress, frictional strength and stress drop while varying the static friction coefficient we found that the break of symmetry makes the rupture dynamics dependent on the absolute value of friction. The higher the friction the stronger the inertial effect both in terms of rupture acceleration and slip amount. When the contact condition allows the fault interface to open close to the free surface, the length of the opening zone is shown to depend on the propagation length, the initial normal stress and the static friction coefficient. These new results are shown to agree with analytical results of rupture propagation in bounded media, and open new perspectives for understanding the shallow rupture of large subduction earthquakes and tsunami sources.

  13. Frequency shifts of resonant modes of the Sun due to near-surface convective scattering

    Science.gov (United States)

    Bhattacharya, J.; Hanasoge, S. M.; Antia, H. M.

    Measurements of oscillation frequencies of the Sun and stars can provide important independent constraints on their internal structure and dynamics. Seismic models of these oscillations are used to connect structure and rotation of the star to its resonant frequencies, which are then compared with observations, the goal being that of minimizing the difference between the two. Even in the case of the Sun, for which structure models are highly tuned, observed frequencies show systematic deviations from modeled frequencies, a phenomenon referred to as the ``surface term.'' The dominant source of this systematic effect is thought to be vigorous near-surface convection, which is not well accounted for in both stellar modeling and mode-oscillation physics. Here we bring to bear the method of homogenization, applicable in the asymptotic limit of large wavelengths (in comparison to the correlation scale of convection), to characterize the effect of small-scale surface convection on resonant-mode frequencies in the Sun. We show that the full oscillation equations, in the presence of temporally stationary 3D flows, can be reduced to an effective ``quiet-Sun'' wave equation with altered sound speed, Brünt-Väisäla frequency, and Lamb frequency. We derive the modified equation and relations for the appropriate averaging of 3D flows and thermal quantities to obtain the properties of this effective medium. Using flows obtained from 3D numerical simulations of near-surface convection, we quantify their effect on solar oscillation frequencies and find that they are shifted systematically and substantially. We argue therefore that consistent interpretations of resonant frequencies must include modifications to the wave equation that effectively capture the impact of vigorous hydrodynamic convection.

  14. FREQUENCY SHIFTS OF RESONANT MODES OF THE SUN DUE TO NEAR-SURFACE CONVECTIVE SCATTERING

    International Nuclear Information System (INIS)

    Bhattacharya, J.; Hanasoge, S.; Antia, H. M.

    2015-01-01

    Measurements of oscillation frequencies of the Sun and stars can provide important independent constraints on their internal structure and dynamics. Seismic models of these oscillations are used to connect structure and rotation of the star to its resonant frequencies, which are then compared with observations, the goal being that of minimizing the difference between the two. Even in the case of the Sun, for which structure models are highly tuned, observed frequencies show systematic deviations from modeled frequencies, a phenomenon referred to as the “surface term.” The dominant source of this systematic effect is thought to be vigorous near-surface convection, which is not well accounted for in both stellar modeling and mode-oscillation physics. Here we bring to bear the method of homogenization, applicable in the asymptotic limit of large wavelengths (in comparison to the correlation scale of convection), to characterize the effect of small-scale surface convection on resonant-mode frequencies in the Sun. We show that the full oscillation equations, in the presence of temporally stationary three-dimensional (3D) flows, can be reduced to an effective “quiet-Sun” wave equation with altered sound speed, Brünt–Väisäla frequency, and Lamb frequency. We derive the modified equation and relations for the appropriate averaging of 3D flows and thermal quantities to obtain the properties of this effective medium. Using flows obtained from 3D numerical simulations of near-surface convection, we quantify their effect on solar oscillation frequencies and find that they are shifted systematically and substantially. We argue therefore that consistent interpretations of resonant frequencies must include modifications to the wave equation that effectively capture the impact of vigorous hydrodynamic convection

  15. Reflectivity reduction of retro-reflector installed in LHD due to plasma surface interaction

    International Nuclear Information System (INIS)

    Yoshida, N.; Ohtawa, Y.; Ebihara, A.; Akiyama, T.; Tokitani, M.; Ashikawa, N.; Kawahata, K.

    2008-10-01

    Optical reflectivity of the retro-reflector installed in LHD as the first mirror was reduced seriously by plasma wall interaction. In order to understand the mechanism of the reflectivity reduction, optical and material properties of the mirror surfaces have been examined extensively. It was found that the deposited impurity layers caused the serious reduction of the reflectivity. Formation of iron oxide, bulges structure and He bubbles are the major factors for the reflectivity reduction in the wide wave length range. (author)

  16. Model for the assessment of surface radionuclide 210 Pb contamination indoors due to presence of radon

    International Nuclear Information System (INIS)

    Mrdja, D.; Bikit, I.; Forkapic, S.

    2009-01-01

    The model is based on the fact that the change of indoor radon concentration, which periodically enters the room, affects only on radioactive decay and the inserted amount of radon in each impact, but not on its diffusion out, i.e. escape from the room. The aim of the model is to assess the surface contamination of the room by lead 210 Pb. (author) [sr

  17. Radiant heat evaluation of concrete: a study of the erosion of concrete due to surface heating

    International Nuclear Information System (INIS)

    Chu, T.Y.

    1978-01-01

    Experiments were carried out to investigate the erosion of concrete under high surface heat flux in connection with the core-melt/concrete interaction studies. The dominate erosion mechanism was found to be melting at the surface accompanied by chemical decomposition of the concrete beneath the melt-solid interface. The erosion process reaches a steady state after an initial transient. The steady state is characterized by an essentially constant erosion rate at the surface and a nonvarying (with respect to the moving melt interface) temperature distribution within the concrete. For the range of incident heat flux 64 W/cm 2 to 118 W/cm 2 , the corresponding steady state erosion rate varies from approximately 8 cm/hr to 23 cm/hr. A simple ablation/melting model is proposed for the erosion process. The model was found to be able to correlate all temperature responses at various depths from all tests at large times and for temperatures above approximately 250 0 C

  18. Assessment of biases in MODIS surface reflectance due to Lambertian approximation

    Energy Technology Data Exchange (ETDEWEB)

    Cook, Robert B [ORNL; SanthanaVannan, Suresh K [ORNL

    2010-08-01

    Using MODIS data and the AERONET-based Surface Reflectance Validation Network (ASRVN), this work studies errors of MODIS atmospheric correction caused by the Lambertian approximation. On one hand, this approximation greatly simplifies the radiative transfer model, reduces the size of the look-up tables, and makes operational algorithm faster. On the other hand, uncompensated atmospheric scattering caused by Lambertian model systematically biases the results. For example, for a typical bowl-shaped bidirectional reflectance distribution function (BRDF), the derived reflectance is underestimated at high solar or view zenith angles, where BRDF is high, and is overestimated at low zenith angles where BRDF is low. The magnitude of biases grows with the amount of scattering in the atmosphere, i.e., at shorter wavelengths and at higher aerosol concentration. The slope of regression of Lambertian surface reflectance vs. ASRVN bidirectional reflectance factor (BRF) is about 0.85 in the red and 0.6 in the green bands. This error propagates into the MODIS BRDF/albedo algorithm, slightly reducing the magnitude of overall reflectance and anisotropy of BRDF. This results in a small negative bias of spectral surface albedo. An assessment for the GSFC (Greenbelt, USA) validation site shows the albedo reduction by 0.004 in the near infrared, 0.005 in the red, and 0.008 in the green MODIS bands.

  19. Mineralogy and Iron Content of the Lunar Polar Regions Using the Kaguya Spectral Profiler and the Lunar Orbiter Laser Altimeter

    Science.gov (United States)

    Lemelin, M.; Lucey, P. G.; Trang, D.; Jha, K.

    2016-12-01

    The lunar polar regions are of high scientific interest, but the extreme lighting conditions have made quantitative analyses using reflectance spectra difficult; some regions are in permanent shadow, and flat surfaces are difficult to correct photometrically due to the extreme grazing incidence and low signal available. Thus, most mineral maps derived from visible and near infrared reflectance spectra have been constrained to within 50° in latitude. The mineralogy of the polar regions, or 44% of the lunar surface, is almost entirely unknown. A few studies have provided compositional analysis based on the spectral shape (where strong absorption bands were present) of lithologies dominated by one or two minerals. In this study, we take a novel approach and use strong signal and well-calibrated reflectance acquired by two different instruments, the Kaguya Spectra Profiler (SP) and the Lunar Orbiter Laser Altimeter (LOLA), in order to derive the first FeO and mineral maps of the polar regions at a spatial resolution of 1 km per pixel. We use reflectance ratios from SP and calibrated reflectance data from LOLA to derive the first polar maps of FeO, which are within 2 wt.% of the FeO measured by the Lunar Prospector Gamma-Ray spectrometer up to 85° in latitude. We then use the reflectance data from SP and Hapke radiative transfer model to compute the abundance of olivine, low-calcium pyroxene, high-calcium pyroxene and plagioclase, using FeO as a constraint. The radiative transfer model yields an error in mineral abundances of 9 wt.%. We use the mineral maps to study the composition of 27 central peaks and 5 basin rings in the polar regions, and relate their composition to their depth of origin in the lunar crust. We find that the central peaks and basin rings in Feldspathic Highlands Terrane are mostly anorthositic in composition, with modal plagioclase content ranging between 66 and 92 wt.%. The central peaks and basin rings in the South Pole-Aitken basin are noritic

  20. Infrared Lunar Laser Ranging at Calern : Impact on Lunar Dynamics

    Science.gov (United States)

    Viswanathan, Vishnu; Fienga, Agnes; Manche, Herve; Gastineau, Mickael; Courde, Clement; Torre, Jean Marie; Exertier, Pierre; Laskar, Jacques

    2017-04-01

    Introduction: Since 2015, in addition to the traditional green (532nm), infrared (1064nm) has been the preferred wavelength for lunar laser ranging at the Calern lunar laser ranging (LLR) site in France. Due to the better atmospheric transmission of IR with respect to Green, nearly 3 times the number of normal points have been obtained in IR than in Green [1]. Dataset: In our study, in addition to the historical data obtained from various other LLR sites, we include the recent IR normal points obtained from Calern over the 1 year time span (2015-2016), constituting about 4.2% of data spread over 46 years of LLR. Near even distribution of data provided by IR on both the spatial and temporal domain, helps us to improve constraints on the internal structure of the Moon modeled within the planetary ephemeris : INPOP [2]. Data reduction: IERS recommended models have been used in the data reduction software GINS (GRGS,CNES) [3]. Constraints provided by GRAIL [4], on the Lunar gravitational potential and Love numbers have been taken into account in the least-square fit procedure. Earth orientation parameters from KEOF series have been used as per a recent study [5]. Results: New estimates on the dynamical parameters of the lunar core will be presented. Acknowledgements: We thank the lunar laser ranging observers at Observatoire de la Côte d'Azur, France, McDonald Observatory, Texas, Haleakala Observatory, Hawaii, and Apache Point Observatory in New Mexico for providing LLR observations that made this study possible. The research described in this abstract was carried out at Geoazur-CNRS, France, as a part of a PhD thesis funded by Observatoire de Paris and French Ministry of Education and Research. References: [1] Clement C. et al. (2016) submitted to A&A [2] Fienga A. et al. (2015) Celest Mech Dyn Astr, 123: 325. doi:10.1007/s10569-015-9639-y [3] Viswanathan V. et al. (2015) EGU, Abstract 18, 13995 [4] Konopliv A. S. et al. (2013) J. Geophys. Res. Planets, 118, 1415

  1. Electrolyzer for NASA Lunar Regenerative Fuel Cells, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Water electrolyzer stacks are a key component of regenerative fuel cells, designed to replace batteries as a means of storing electric energy on the lunar surface....

  2. Cycles of Air Temperature According to Lunar Parallax

    Directory of Open Access Journals (Sweden)

    Isaia Ion

    2016-06-01

    Full Text Available This paper proposes to demonstrate that, on Terra’s surface, there are cycles of air’s temperature (almost perfect, which can be explained just by the lunar parallax’s cycles.

  3. Impact-Actuated Digging Tool for Lunar Excavation, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Honeybee Robotics proposes to develop a vacuum compatible, impact-actuated digging tool for the excavation of frozen and compacted regolith on the lunar surface and...

  4. Consolidated Lunar Atlas

    Data.gov (United States)

    National Aeronautics and Space Administration — The Consolidated Lunar Atlas is a collection of the best photographic images of the moon, including low-oblique photography, full-moon photography, and tabular and...

  5. Use of a Lunar Outpost for Developing Space Settlement Technologies

    Science.gov (United States)

    Purves, Lloyd R.

    2008-01-01

    The type of polar lunar outpost being considered in the NASA Vision for Space Exploration (VSE) can effectively support the development of technologies that will not only significantly enhance lunar exploration, but also enable long term crewed space missions, including space settlement. The critical technologies are: artificial gravity, radiation protection, Closed Ecological Life Support Systems (CELSS) and In-Situ Resource Utilization (ISRU). These enhance lunar exploration by extending the time an astronaut can remain on the moon and reducing the need for supplies from Earth, and they seem required for space settlement. A polar lunar outpost provides a location to perform the research and testing required to develop these technologies, as well as to determine if there are viable countermeasures that can reduce the need for Earth-surface-equivalent gravity and radiation protection on long human space missions. The types of spinning space vehicles or stations envisioned to provide artificial gravity can be implemented and tested on the lunar surface, where they can create any level of effective gravity above the 1/6 Earth gravity that naturally exists on the lunar surface. Likewise, varying degrees of radiation protection can provide a natural radiation environment on the lunar surface less than or equal to 1/2 that of open space at 1 AU. Lunar ISRU has the potential of providing most of the material needed for radiation protection, the centrifuge that provides artificial gravity; and the atmosphere, water and soil for a CELSS. Lunar ISRU both saves the cost of transporting these materials from Earth and helps define the requirements for ISRU on other planetary bodies. Biosphere II provides a reference point for estimating what is required for an initial habitat with a CELSS. Previous studies provide initial estimates of what would be required to provide such a lunar habitat with the gravity and radiation environment of the Earth s surface. While much preparatory

  6. Hyper-resistivity and electron thermal conductivity due to destroyed magnetic surfaces in axisymmetric plasma equilibria

    Energy Technology Data Exchange (ETDEWEB)

    Weening, R. H. [Department of Radiologic Sciences, Thomas Jefferson University, 901 Walnut Street, Philadelphia, Pennsylvania 19107-5233 (United States)

    2012-06-15

    In order to model the effects of small-scale current-driven magnetic fluctuations in a mean-field theoretical description of a large-scale plasma magnetic field B(x,t), a space and time dependent hyper-resistivity {Lambda}(x,t) can be incorporated into the Ohm's law for the parallel electric field E Dot-Operator B. Using Boozer coordinates, a theoretical method is presented that allows for a determination of the hyper-resistivity {Lambda}({psi}) functional dependence on the toroidal magnetic flux {psi} for arbitrary experimental steady-state Grad-Shafranov axisymmetric plasma equilibria, if values are given for the parallel plasma resistivity {eta}({psi}) and the local distribution of any auxiliary plasma current. Heat transport in regions of plasma magnetic surfaces destroyed by resistive tearing modes can then be modeled by an electron thermal conductivity k{sub e}({psi})=({epsilon}{sub 0}{sup 2}m{sub e}/e{sup 2}){Lambda}({psi}), where e and m{sub e} are the electron charge and mass, respectively, while {epsilon}{sub 0} is the permittivity of free space. An important result obtained for axisymmetric plasma equilibria is that the {psi}{psi}-component of the metric tensor of Boozer coordinates is given by the relation g{sup {psi}{psi}}({psi}){identical_to}{nabla}{psi} Dot-Operator {nabla}{psi}=[{mu}{sub 0}G({psi})][{mu}{sub 0}I({psi})]/{iota}({psi}), with {mu}{sub 0} the permeability of free space, G({psi}) the poloidal current outside a magnetic surface, I({psi}) the toroidal current inside a magnetic surface, and {iota}({psi}) the rotational transform.

  7. The Chameleon Effect: Characterization Challenges Due to the Variability of Nanoparticles and Their Surfaces

    Directory of Open Access Journals (Sweden)

    Donald R. Baer

    2018-05-01

    Full Text Available Nanoparticles in a variety of forms are increasing important in fundamental research, technological and medical applications, and environmental or toxicology studies. Physical and chemical drivers that lead to multiple types of particle instabilities complicate both the ability to produce, appropriately characterize, and consistently deliver well-defined particles, frequently leading to inconsistencies, and conflicts in the published literature. This perspective suggests that provenance information, beyond that often recorded or reported, and application of a set of core characterization methods, including a surface sensitive technique, consistently applied at critical times can serve as tools in the effort minimize reproducibility issues.

  8. The Chameleon Effect: characterization challenges due to the variability of nanoparticles and their surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Baer, Donald R.

    2018-05-07

    Nanoparticles in a variety of forms are of increasing importance in fundamental research, technological and medical applications, and environmental or toxicology studies. Physical and chemical drivers that lead to multiple types of particle instabilities complicate both the ability to produce and consistently deliver well defined particles and their appropriate characterization, frequently leading to inconsistencies and conflicts in the published literature. This perspective suggests that provenance information, beyond that often recorded or reported, and application of a set of core characterization methods, including a surface sensitive technique, consistently applied at critical times can serve as tools in the effort minimize reproducibility issues.

  9. Lunar Prospector Orbit Determination Uncertainties Using the High Resolution Lunar Gravity Models

    Science.gov (United States)

    Carranza, Eric; Konopliv, Alex; Ryne, Mark

    1999-01-01

    The Lunar Prospector (LP) mission began on January 6, 1998, when the LP spacecraft was launched from Cape Canaveral, Florida. The objectives of the mission were to determine whether water ice exists at the lunar poles, generate a global compositional map of the lunar surface, detect lunar outgassing, and improve knowledge of the lunar magnetic and gravity fields. Orbit determination of LP performed at the Jet Propulsion Laboratory (JPL) is conducted as part of the principal science investigation of the lunar gravity field. This paper will describe the JPL effort in support of the LP Gravity Investigation. This support includes high precision orbit determination, gravity model validation, and data editing. A description of the mission and its trajectory will be provided first, followed by a discussion of the orbit determination estimation procedure and models. Accuracies will be examined in terms of orbit-to-orbit solution differences, as a function of oblateness model truncation, and inclination in the plane-of-sky. Long term predictions for several gravity fields will be compared to the reconstructed orbits to demonstrate the accuracy of the orbit determination and oblateness fields developed by the Principal Gravity Investigator.

  10. Segmented Mirror Image Degradation Due to Surface Dust, Alignment and Figure

    Science.gov (United States)

    Schreur, Julian J.

    1999-01-01

    In 1996 an algorithm was developed to include the effects of surface roughness in the calculation of the point spread function of a telescope mirror. This algorithm has been extended to include the effects of alignment errors and figure errors for the individual elements, and an overall contamination by surface dust. The final algorithm builds an array for a guard-banded pupil function of a mirror that may or may not have a central hole, a central reflecting segment, or an outer ring of segments. The central hole, central reflecting segment, and outer ring may be circular or polygonal, and the outer segments may have trimmed comers. The modeled point spread functions show that x-tilt and y-tilt, or the corresponding R-tilt and theta-tilt for a segment in an outer ring, is readily apparent for maximum wavefront errors of 0.1 lambda. A similar sized piston error is also apparent, but integral wavelength piston errors are not. Severe piston error introduces a focus error of the opposite sign, so piston could be adjusted to compensate for segments with varying focal lengths. Dust affects the image principally by decreasing the Strehl ratio, or peak intensity of the image. For an eight-meter telescope a 25% coverage by dust produced a scattered light intensity of 10(exp -9) of the peak intensity, a level well below detectability.

  11. Concentrations of radioactive elements in lunar materials

    Science.gov (United States)

    Korotev, Randy L.

    1998-01-01

    As an aid to interpreting data obtained remotely on the distribution of radioactive elements on the lunar surface, average concentrations of K, U, and Th as well as Al, Fe, and Ti in different types of lunar rocks and soils are tabulated. The U/Th ratio in representative samples of lunar rocks and regolith is constant at 0.27; K/Th ratios are more variable because K and Th are carried by different mineral phases. In nonmare regoliths at the Apollo sites, the main carriers of radioactive elements are mafic (i.e., 6-8 percent Fe) impact-melt breccias created at the time of basin formation and products derived therefrom.

  12. Lunar Soil Erosion Physics for Landing Rockets on the Moon

    Science.gov (United States)

    Clegg, Ryan; Metzger, Philip; Roberson, Luke; Stephen, Huff

    2010-03-01

    To develop a lunar outpost, we must understand the blowing of soil during launch and landing of the new Altair Lander. For example, the Apollo 12 Lunar Module landed approximately 165 meters from the deactivated Surveyor III spacecraft, scouring its surfaces and creating numerous tiny pits. Based on simulations and video analysis from the Apollo missions, blowing lunar soil particles have velocities up to 2000 m/s at low ejection angles relative to the horizon, reach an apogee higher than the orbiting Command and Service Module, and travel nearly the circumference of the Moon. The low ejection angle and high velocity are concerns for the lunar outpost. As a first step in investigating this concern, we have performed a series of low-velocity impact experiments in a modified sandblasting hood using lunar soil simulant impacted upon various materials that are commonly used in spaceflight hardware. It was seen that considerable damage is inevitable and protective barriers need to be designed.

  13. "First Convention of Lunar Explorers" - Invitation to the media

    Science.gov (United States)

    2001-03-01

    The first LUNEX Convention will bring together lunar explorers from all backgrounds, including professionals, amateur space enthusiasts and interested visitors from the public. During the Convention numerous oral presentations will prompt detailed discussions on all aspects of future lunar exploration: the Moon as a geology laboratory or an astronomical platform; the knowledge of lunar geography needed to land and move on the surface; the implications of finding water-ice on the Moon and whether this might be detected by forthcoming missions; the architecture of lunar habitats; what would be needed in the future for the Moon to support life; cultural and social aspects; and the scientific motivation for returning to the Moon. The Convention will also be the main public event in 2001 at which SMART-1 is presented. SMART-1, due to be launched in 2002 will test solar electric propulsion and other innovative approaches for future deep space probes. It is the first European satellite to be sent towards the Moon. Visitors to the Palais de la Découverte will be able to view a model of SMART-1. On 9 March, at 09:00, the media is invited to hear about the LUNEX objectives and activities and to learn about the European Space Agency’s SMART-1 mission within the broader context of ESA’s Planetary Exploration Programme. Background information on LUNEX The Lunar Explorers Society (LUNEX) is an international organization created by 200 founder members in July 2000. LUNEX was founded at the end of the 4th Conference on Exploration and Utilisation of the Moon (ICEUM4), organised by ESA and the International Lunar Exploration Working Group (ILEWG). Its aim is to promote the exploration of the Moon for the benefit of humanity, bridging the gap between space agencies and the general public to promote planetary exploration and space. The Lunar Explorers Society invites all interested individuals to become members. Background information on SMART-1 SMART-1 is the first of ESA

  14. Beneficiation of lunar ilmenite

    Science.gov (United States)

    Ruiz, Joaquin

    1991-01-01

    One of the most important commodities lacking in the moon is free oxygen which is required for life and used extensively for propellent. Free oxygen, however, can be obtained by liberating it from the oxides and silicates that form the lunar rocks and regolith. Ilmenite (FeTiO3) is considered one of the leading candidates for production of oxygen because it can be reduced with a reasonable amount of energy and it is an abundant mineral in the lunar regolith and many mare basalts. In order to obtain oxygen from ilmenite, a method must be developed to beneficiate ilmenite from lunar material. Two possible techniques are electrostatic or magnetic methods. Both methods have complications because lunar ilmenite completely lacks Fe(3+). Magnetic methods were tested on eucrite meteorites, which are a good chemical simulant for low Ti mare basalts. The ilmenite yields in the experiments were always very low and the eucrite had to be crushed to xxxx. These data suggest that magnetic separation of ilmenite from fine grain lunar basalts would not be cost effective. Presently, experiments are being performed with electrostatic separators, and lunar regolith is being waited for so that simulants do not have to be employed.

  15. Lunar Sample Compendium

    Science.gov (United States)

    Meyer, Charles

    2005-01-01

    The purpose of the Lunar Sample Compendium will be to inform scientists, astronauts and the public about the various lunar samples that have been returned from the Moon. This Compendium will be organized rock by rock in the manor of a catalog, but will not be as comprehensive, nor as complete, as the various lunar sample catalogs that are available. Likewise, this Compendium will not duplicate the various excellent books and reviews on the subject of lunar samples (Cadogen 1981, Heiken et al. 1991, Papike et al. 1998, Warren 2003, Eugster 2003). However, it is thought that an online Compendium, such as this, will prove useful to scientists proposing to study individual lunar samples and should help provide backup information for lunar sample displays. This Compendium will allow easy access to the scientific literature by briefly summarizing the significant findings of each rock along with the documentation of where the detailed scientific data are to be found. In general, discussion and interpretation of the results is left to the formal reviews found in the scientific literature. An advantage of this Compendium will be that it can be updated, expanded and corrected as need be.

  16. Heterogeneity in lunar anorthosite meteorites: implications for the lunar magma ocean model.

    Science.gov (United States)

    Russell, Sara S; Joy, Katherine H; Jeffries, Teresa E; Consolmagno, Guy J; Kearsley, Anton

    2014-09-13

    The lunar magma ocean model is a well-established theory of the early evolution of the Moon. By this model, the Moon was initially largely molten and the anorthositic crust that now covers much of the lunar surface directly crystallized from this enormous magma source. We are undertaking a study of the geochemical characteristics of anorthosites from lunar meteorites to test this model. Rare earth and other element abundances have been measured in situ in relict anorthosite clasts from two feldspathic lunar meteorites: Dhofar 908 and Dhofar 081. The rare earth elements were present in abundances of approximately 0.1 to approximately 10× chondritic (CI) abundance. Every plagioclase exhibited a positive Eu-anomaly, with Eu abundances of up to approximately 20×CI. Calculations of the melt in equilibrium with anorthite show that it apparently crystallized from a magma that was unfractionated with respect to rare earth elements and ranged in abundance from 8 to 80×CI. Comparisons of our data with other lunar meteorites and Apollo samples suggest that there is notable heterogeneity in the trace element abundances of lunar anorthosites, suggesting these samples did not all crystallize from a common magma source. Compositional and isotopic data from other authors also suggest that lunar anorthosites are chemically heterogeneous and have a wide range of ages. These observations may support other models of crust formation on the Moon or suggest that there are complexities in the lunar magma ocean scenario to allow for multiple generations of anorthosite formation. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  17. Mafic Materials in Scott Crater? A Test for Lunar Reconnaissance Orbiter

    Science.gov (United States)

    Cooper, Bonnie L.

    2007-01-01

    Clementine 750 nm and multispectral ratio data, along with Lunar Orbiter and radar data, were used to study the crater Scott in the lunar south polar region. The multispectral data provide evidence for mafic materials, impact melts, anorthositic materials, and a small pyroclastic deposit. High-resolution radar data and Lunar Orbiter photography for this area show differences in color and surface texture that correspond with the locations of the hypothesized mafic and anorthositic areas on the crater floor. This region provides a test case for the upcoming Lunar Reconnaissance Orbiter. Verification of the existence of a mafic deposit at this location is relevant to future lunar resource utilization planning.

  18. Electrical conductivity of the lunar interior - Theory, error sources, and estimates

    Science.gov (United States)

    Goldstein, B. E.

    1979-01-01

    Estimates of the electrical conductivity of the lunar interior were previously obtained by comparison of magnetometer data at the lunar surface and in near lunar space. In studies based on solar wind observations, IR was assumed that fields induced in the lunar interior by time-varying external fields are confined by the solar wind within the lunar interior on the dayside and within a cylindrical plasma cavity on the nightside. In the present paper, the induced fields are calculated for a more realistic conical plasma cavity geometry.

  19. Procedure to approximately estimate the uncertainty of material ratio parameters due to inhomogeneity of surface roughness

    International Nuclear Information System (INIS)

    Hüser, Dorothee; Thomsen-Schmidt, Peter; Hüser, Jonathan; Rief, Sebastian; Seewig, Jörg

    2016-01-01

    Roughness parameters that characterize contacting surfaces with regard to friction and wear are commonly stated without uncertainties, or with an uncertainty only taking into account a very limited amount of aspects such as repeatability of reproducibility (homogeneity) of the specimen. This makes it difficult to discriminate between different values of single roughness parameters. Therefore uncertainty assessment methods are required that take all relevant aspects into account. In the literature this is rarely performed and examples specific for parameters used in friction and wear are not yet given. We propose a procedure to derive the uncertainty from a single profile employing a statistical method that is based on the statistical moments of the amplitude distribution and the autocorrelation length of the profile. To show the possibilities and the limitations of this method we compare the uncertainty derived from a single profile with that derived from a high statistics experiment. (paper)

  20. Closer look at lunar volcanism

    International Nuclear Information System (INIS)

    Vaniman, D.T.; Heiken, G.; Taylor, G.J.

    1984-01-01

    Although the American Apollo and Soviet Luna missions concentrated on mare basalt samples, major questions remain about lunar volcanism. Lunar field work will be indispensable for resolving the scientific questions about ages, compositions, and eruption processes of lunar volcanism. From a utilitarian standpoint, a better knowledge of lunar volcanism will also yield profitable returns in lunar base construction (e.g., exploitation of rille or lava-tube structures) and in access to materials such as volatile elements, pure glass, or ilmenite for lunar industry

  1. Apollo 11 Astronaut Neil Armstrong During Lunar Rock Collection Training

    Science.gov (United States)

    1969-01-01

    In this photograph, Apollo 11 astronaut Neil A. Armstrong uses a geologist's hammer in selecting rock specimens during a geological field trip to the Quitman Mountains area near the Fort Quitman ruins in far west Texas. Armstrong, alongside astronaut Edwin (Buzz) Aldrin, practiced gathering rock specimens using special lunar geological tools in preparation for the first Lunar landing. Mission was accomplished in July of the same year. Aboard the Marshall Space Fight center (MSFC) developed Saturn V launch vehicle, the Apollo 11 mission launched from The Kennedy Space Center, Florida on July 16, 1969 and safely returned to Earth on July 24, 1969. The 3-man crew aboard the flight consisted of Armstrong, commander; Aldrin, Lunar Module pilot; and a third astronaut Michael Collins, Command Module pilot. Armstrong was the first human to ever stand on the lunar surface, followed by Aldrin, while Collins remained in lunar orbit. The crew collected 47 pounds of lunar surface material which was returned to Earth for analysis. The lunar surface exploration was concluded in 2½ hours.

  2. Predicting the Blast of Lunar Soil Under a Rocket's Exhaust Jet

    Science.gov (United States)

    Diaz, Carlos J. Sanchez

    2007-01-01

    The blast of lunar soil represents a problem for the future missions planned for the moon. When the lander approached the ground during the Apollo missions, huge showers of dust particles were sent in all directions at extremely high velocities - including upwards towards the landing spacecraft. This represents a clear danger to the lander because the loss of visibility and the damage that can be produced to the vehicle itself. If there had been equipment on the ground, these showers of particles would have created a sand blasting effect over the equipment, possibly damaging optics and contaminating the equipment and depending on the size and velocity of the particles maybe even more extensive damage as the particles penetrated the outer surface of the equipment. Since the there is no air on the moon to slow down the particles, they can travel large distances at high speeds, in fact in some instances they can reach near escape velocity and go into an orbit around the moon and come all the way back to almost the same point where they were at the beginning; meaning that some of the lunar dust that came up during landing will shower back over the site. Once on the surface, the extremely fine dust had a habit of getting itself everywhere. During the Apollo missions it not only covered the astronauts' suits, but managed to work its way inside, damaging airtight joints and scratching up glass visors. The dust found its way inside the spacecraft, contaminating the floor and electronic systems inside, clogging air filters in the process. This is due to the fact that the lunar soil is extremely cohesive. The Lunar soil causes all of the same problems as sand does on Earth but unlike sand particles on Earth, which have smooth spherical shapes, the dust on the Moon is more like small particles of glass with sharper edges since there is no erosion on the lunar surface. During the Apollo missions the dust problem did not cause a big problem due to the fact of the length of

  3. SELENE - Self-Forming Extensible Lunar EVA Network, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar EVA network will exhibit a wide range of connectivity levels due to the challenging communications environment and mission dynamics. Disruption-Tolerant...

  4. COMPARATIVE STUDY OF LUNAR ROUGHNESS FROM MULTI - SOURCE DATA

    Directory of Open Access Journals (Sweden)

    Y. Lou

    2017-07-01

    Full Text Available The lunar terrain can show its collision and volcanic history. The lunar surface roughness can give a deep indication of the effects of lunar surface magma, sedimentation and uplift. This paper aims to get different information from the roughness through different data sources. Besides introducing the classical Root-mean-square height method and Morphological Surface Roughness (MSR algorithm, this paper takes the area of the Jurassic mountain uplift in the Sinus Iridum and the Plato Crater area as experimental areas. And then make the comparison and contrast of the lunar roughness derived from LRO's DEM and CE-2 DOM. The experimental results show that the roughness obtained by the traditional roughness calculation method reflect the ups and downs of the topography, while the results obtained by morphological surface roughness algorithm show the smoothness of the lunar surface. So, we can first use the surface fluctuation situation derived from RMSH to select the landing area range which ensures the lands are gentle. Then the morphological results determine whether the landing area is suitable for the detector walking and observing. The results obtained at two different scales provide a more complete evaluation system for selecting the landing site of the lunar probe.

  5. 2007 Lunar Regolith Simulant Workshop Overview

    Science.gov (United States)

    McLemore, Carole A.; Fikes, John C.; Howell, Joe T.

    2007-01-01

    The National Aeronautics and Space Administration (NASA) vision has as a cornerstone, the establishment of an Outpost on the Moon. This Lunar Outpost will eventually provide the necessary planning, technology development, and training for a manned mission to Mars in the future. As part of the overall activity, NASA is conducting Earth-based research and advancing technologies to a Technology Readiness Level (TRL) 6 maturity under the Exploration Technology Development Program that will be incorporated into the Constellation Project as well as other projects. All aspects of the Lunar environment, including the Lunar regolith and its properties, are important in understanding the long-term impacts to hardware, scientific instruments, and humans prior to returning to the Moon and living on the Moon. With the goal of reducing risk to humans and hardware and increasing mission success on the Lunar surface, it is vital that terrestrial investigations including both development and verification testing have access to Lunar-like environments. The Marshall Space Flight Center (MSFC) is supporting this endeavor by developing, characterizing, and producing Lunar simulants in addition to analyzing existing simulants for appropriate applications. A Lunar Regolith Simulant Workshop was conducted by MSFC in Huntsville, Alabama, in October 2007. The purpose of the Workshop was to bring together simulant developers, simulant users, and program and project managers from ETDP and Constellation with the goals of understanding users' simulant needs and their applications. A status of current simulant developments such as the JSC-1A (Mare Type Simulant) and the NASA/U.S. Geological Survey Lunar Highlands-Type Pilot Simulant (NU-LHT-1 M) was provided. The method for evaluating simulants, performed via Figures of Merit (FoMs) algorithms, was presented and a demonstration was provided. The four FoM properties currently being assessed are: size, shape, density, and composition. Some of the

  6. A Dual Launch Robotic and Human Lunar Mission Architecture

    Science.gov (United States)

    Jones, David L.; Mulqueen, Jack; Percy, Tom; Griffin, Brand; Smitherman, David

    2010-01-01

    This paper describes a comprehensive lunar exploration architecture developed by Marshall Space Flight Center's Advanced Concepts Office that features a science-based surface exploration strategy and a transportation architecture that uses two launches of a heavy lift launch vehicle to deliver human and robotic mission systems to the moon. The principal advantage of the dual launch lunar mission strategy is the reduced cost and risk resulting from the development of just one launch vehicle system. The dual launch lunar mission architecture may also enhance opportunities for commercial and international partnerships by using expendable launch vehicle services for robotic missions or development of surface exploration elements. Furthermore, this architecture is particularly suited to the integration of robotic and human exploration to maximize science return. For surface operations, an innovative dual-mode rover is presented that is capable of performing robotic science exploration as well as transporting human crew conducting surface exploration. The dual-mode rover can be deployed to the lunar surface to perform precursor science activities, collect samples, scout potential crew landing sites, and meet the crew at a designated landing site. With this approach, the crew is able to evaluate the robotically collected samples to select the best samples for return to Earth to maximize the scientific value. The rovers can continue robotic exploration after the crew leaves the lunar surface. The transportation system for the dual launch mission architecture uses a lunar-orbit-rendezvous strategy. Two heavy lift launch vehicles depart from Earth within a six hour period to transport the lunar lander and crew elements separately to lunar orbit. In lunar orbit, the crew transfer vehicle docks with the lander and the crew boards the lander for descent to the surface. After the surface mission, the crew returns to the orbiting transfer vehicle for the return to the Earth. This

  7. Metabolism of tritium uptake due to handling of metal surfaces exposed to tritiated hydrogen gas

    International Nuclear Information System (INIS)

    Johnson, J.R.; Peterman, B.F.

    1987-08-01

    Hairless rats were exposed to tritium by rubbing HT contaminated stainless steel planchets on them. The pattern of tritium excretion in the urine (n=4), shows the OBT (organically bound tritium) retention curve to be approximated by the sum of 2 exponential curves, one with a half-life of 0.4 days and another with a half-life of 1.4 days. The retention of HTO fit a single exponential curve with a half-life of 3.1 days. Exposed skin, unexposed skin, liver, muscle and blood (n=6) were assayed for HBO, and free HTO. Highest activity was found in the exposed skin, other organs with high activity are the unexposed skin and liver. Examination of the exposed skin showed HTO to be concentrated in the uppermost layers. The distribution of OBT was similar but was incorporated at a faster rate. The basal layer is exposed to a tritium concentration between 70-90% of that of the surface. The two macromolecule fractions with the highest amount of radioactivity were lipid and insoluble protein (mainly collagen)

  8. LOTT: A new small telescope to monitor lunar orientation parameters

    Science.gov (United States)

    Huang, Cheng-Li

    2015-08-01

    The lunar orientation (mostly libration) is so far mostly determined by lunar laser ranging (LLR), but due to the bad geometry among thelaser ray direction and the lunar reflector array, the lunar orientation parameters (LOP) are determined with precision worse than 0.1 arcsecond, especially of the components perpendicular to the direction pointing to geocenter. The LOP with such bad precision is almost nonsense for studying the lunar interior, and the error in the modeling of LOP becomes also a major error in the lunar ephemerides. Here, we propose a small optical telescope (LOTT: Lunar Orientation Trinity Telescope), with a brand-new design of tri-field of view and to be placed on the Moon, to monitor LOP and its variation. Its precision of LOP determination can be expected to be several milliarcsecond (mas) after two months observation. With this precision, LOP can then be used to derive meaningful information of the physics of the lunar interior. The concept and design of this LOTT will be introduced, and the test observation data of EOP by this principled sample machine on the earth, as well as the design of the second generation of LOTT, will be also presented.

  9. Subepithelial corneal fibrosis partially due to epithelial-mesenchymal transition of ocular surface epithelium

    Science.gov (United States)

    Kawashima, Motoko; Higa, Kazunari; Satake, Yoshiyuki; Omoto, Masahiro; Tsubota, Kazuo; Shimmura, Shigeto; Shimazaki, Jun

    2010-01-01

    Purpose To determine whether epithelial-mesenchymal transition is involved in the development of corneal subepithelial fibrosis (pannus). Methods Frozen samples of pannus tissue removed from human corneas with a diagnosis of total limbal stem cell deficiency were characterized by immunostaining for both epithelial and mesenchymal markers. We selected transformation-related protein 63 (p63) and pancytokeratin as epithelial markers and vimentin and α-smooth muscle actin (α-SMA) as mesenchymal markers. Immunostaining for β-catenin and E-cadherin was performed to determine wingless-Int (Wnt)-pathway activation. RT–PCR analysis was also performed on epithelial tissue obtained from pannus samples after dispase digestion. Results Immunohistochemistry revealed strong nuclear expression of p63 and weak intercellular expression of E-cadherin in epithelial basal cells of pannus tissue. Furthermore, translocation of β-catenin from intercellular junctions to the nucleus and cytoplasm was also observed. Double-positive cells for both p63 and α-SMA were observed in the subepithelial stroma of pannus tissue, which was supported by RT–PCR and cytospin analysis. Conclusions Epithelial-mesenchymal transition may be partially involved in the development of subepithelial corneal fibrosis due to total limbal stem cell deficiency. PMID:21179238

  10. Transient thermal stresses due to a zonal heat source moving back and forth over the surface on an infinite plate

    International Nuclear Information System (INIS)

    Sumi, N.; Hetnarski, R.B.

    1989-01-01

    A solution is given for the transient thermal stresses due to a zonal heat source moving back and forth with a constant angular frequency over the surface of an infinite elastic plate. The transient temperature distribution is obtained by using the complex Fourier and Laplace transforms, and the associated thermal stresses are obtained by means of the thermoelastic displacement potential and the Galerkin function. Graphical representations for the solution in dimensionless terms are included in this paper. (orig.)

  11. Temporal Variability of Lunar Exospheric Helium During January 2012 from LRO/LAMP

    OpenAIRE

    Feldman, Paul D.; Hurley, Dana M.; Retherford, Kurt D.; Gladstone, G. Randall; Stern, S. Alan; Pryor, Wayne; Parker, Joel Wm.; Kaufmann, David E.; Davis, Michael W.; Versteeg, Maarten; team, LAMP

    2012-01-01

    We report observations of the lunar helium exosphere made between December 29, 2011, and January 26, 2012, with the Lyman Alpha Mapping Project (LAMP) ultraviolet spectrograph on NASA's Lunar Reconnaissance Orbiter Mission (LRO). The observations were made of resonantly scattered He I 584 from illuminated atmosphere against the dark lunar surface on the dawn side of the terminator. We find no or little variation of the derived surface He density with latitude but day-to-day variations that li...

  12. Blocky craters: implications about the lunar megaregolith

    International Nuclear Information System (INIS)

    Thompson, T.W.; Roberts, W.J.; Hartmann, W.K.; Shorthill, R.W.; Zisk, S.H.

    1979-01-01

    Radar, infrared, and photogeologic properties of lunar craters have been studied to determine whether there is a systematic difference in blocky craters between the maria and terrae and whether this difference may be due to a deep megaregolith of pulverized material forming the terra surface, as opposed to a layer of semi-coherent basalt flows forming the mare surface. Some 1310 craters from about 4 to 100 km diameter have been catalogued as radar and/or infrared anomalies. In addition, a study of Apollo Orbital Photography confirmed that the radar and infrared anomalies are correlated with blocky rubble around the crater. Analysis of the radar and infrared data indicated systematic terra-mare differences. Fresh terra craters smaller than 12 km were less likely to be infrared and radar anomalies than comparable mare craters: but terra and mare craters larger than 12 km had similar infrared and radar signatures. Also, there are many terra craters which are radar bright but not infrared anomalies. The authors interpretation of these data is that while the maria are rock layers (basaltic flow units) where craters eject boulder fields, the terrae are covered by relatively pulverized megaregolith at least 2 km deep, where craters eject less rocky rubble. Blocky rubble, either in the form of actual rocks or partly consolidated blocks, contributes to the radar and infrared signatures of the crater. However, aging by impacts rapidly destroys these effects, possibly through burial by secondary debris or by disintegration of the blocks themselves, especially in terra regions. (Auth.)

  13. Positive hepatitis B surface antigen tests due to recent vaccination: a persistent problem

    Directory of Open Access Journals (Sweden)

    Rysgaard Carolyn D

    2012-09-01

    Full Text Available Abstract Background Hepatitis B virus (HBV is a common cause of viral hepatitis with significant health complications including cirrhosis and hepatocellular carcinoma. Assays for hepatitis B surface antigen (HBsAg are the most frequently used tests to detect HBV infection. Vaccination for HBV can produce transiently detectable levels of HBsAg in patients. However, the time course and duration of this effect is unclear. The objective of this retrospective study was to clarify the frequency and duration of transient HBsAg positivity following vaccination against HBV. Methods The electronic medical record at an academic tertiary care medical center was searched to identify all orders for HBsAg within a 17 month time period. Detailed chart review was performed to identify all patients who were administered HBV vaccine within 180 days prior to HBsAg testing and also to ascertain likely cause of weakly positive (grayzone results. Results During the 17 month study period, 11,719 HBsAg tests were ordered on 9,930 patients. There were 34 tests performed on 34 patients who received HBV vaccine 14 days or less prior to HBsAg testing. Of these 34 patients, 11 had grayzone results for HBsAg that could be attributed to recent vaccination. Ten of the 11 patients were renal dialysis patients who were receiving HBsAg testing as part of routine and ongoing monitoring. Beyond 14 days, there were no reactive or grayzone HBsAg tests that could be attributed to recent HBV vaccination. HBsAg results reached a peak COI two to three days following vaccination before decaying. Further analysis of all the grayzone results within the 17 month study period (43 results out of 11,719 tests revealed that only 4 of 43 were the result of true HBV infection as verified by confirmatory testing. Conclusions Our study confirms that transient HBsAg positivity can occur in patients following HBV vaccination. The results suggest this positivity is unlikely to persist beyond 14 days

  14. Lunar geophysics, geodesy, and dynamics

    Science.gov (United States)

    Williams, J. G.; Dickey, J. O.

    2002-01-01

    Experience with the dynamics and data analyses for earth and moon reveals both similarities and differences. Analysis of Lunar Laser Ranging (LLR) data provides information on the lunar orbit, rotation, solid-body tides, and retroreflector locations.

  15. The Future Lunar Flora Colony

    Science.gov (United States)

    Goel, E. G.; Guven, U. G.

    2017-10-01

    A constructional design for the primary establishment for a lunar colony using the micrometeorite rich soil is proposed. It highlights the potential of lunar regolith combined with Earth technology for water and oxygen for human outposts on the Moon.

  16. Lunar Prospecting With Chandra

    Science.gov (United States)

    2003-09-01

    Observations of the bright side of the Moon with NASA's Chandra X-ray Observatory have detected oxygen, magnesium, aluminum and silicon over a large area of the lunar surface. The abundance and distribution of those elements will help to determine how the Moon was formed. "We see X-rays from these elements directly, independent of assumptions about the mineralogy and other complications," said Jeremy Drake of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., at a press conference at the "Four Years with Chandra" symposium in Huntsville, Alabama. "We have Moon samples from the six widely-space Apollo landing sites, but remote sensing with Chandra can cover a much wider area," continued Drake. "It's the next best thing to being there, and it's very fast and cost-effective." The lunar X-rays are caused by fluorescence, a process similar to the way that light is produced in fluorescent lamps. Solar X-rays bombard the surface of the Moon, knock electrons out of the inner parts of the atoms, putting them in a highly unstable state. Almost immediately, other electrons rush to fill the gaps, and in the process convert their energy into the fluorescent X-rays seen by Chandra. According to the currently popular "giant impact" theory for the formation of the Moon, a body about the size of Mars collided with the Earth about 4.5 billion years ago. This impact flung molten debris from the mantle of both the Earth and the impactor into orbit around the Earth. Over the course of tens of millions of years, the debris stuck together to form the Moon. By measuring the amounts of aluminum and other elements over a wide area of the Moon and comparing them to the Earth's mantle, Drake and his colleagues plan to help test the giant impact hypothesis. "One early result," quipped Drake, "is that there is no evidence for large amounts of calcium, so cheese is not a major constituent of the Moon." Illustration of Earth's Geocorona Illustration of Earth's Geocorona The same

  17. Frequency hopping due to acousto-electric interaction in ZnO based surface acoustic wave oscillator

    Science.gov (United States)

    Dasgupta, Daipayan; Sreenivas, K.

    2011-08-01

    A 36 MHz surface acoustic wave delay line based oscillator has been used to study the effect of acousto-electric interaction due to photo generated charge carriers in rf sputtered ZnO film under UV illumination (λ = 365 nm, 20-100 μW/cm2). Design aspects for developing a delay line based SAW oscillator are specified. The observed linear downshift in frequency (2.2 to 19.0 kHz) with varying UV intensity (20-100 μW/cm2) is related to the fractional velocity change due to acousto-electric interaction. UV illumination level of 100 μW/cm2 leads to a characteristic frequency hopping behavior arising due to a change in the oscillation criteria, and is attributed to the complex interplay between the increased attenuation and velocity shift.

  18. Consequences of the low density of the lunar primary crust on its magmatic history (Invited)

    Science.gov (United States)

    Michaut, C.; Thorey, C.

    2013-12-01

    The lunar highlands are very old, with ages covering a timespan between 4.5 to 4.2 Gyr, and probably formed by flotation of light plagioclase minerals on top of the lunar magma ocean. The lunar crust provides thus an invaluable evidence of the geological and magmatic processes occurring in the first times of the terrestrial planets history. According to the last estimates from the GRAIL mission, the lunar primary crust is particularly light and relatively thick. This low-density crust acted as a barrier for the dense primary mantle melts. This is particularly evident in the fact that subsequent mare basalts erupted primarily within large impact basins: at least part of the crust must have been removed for the magma to reach the surface. However, the trajectory of the magma from the mantle to the surface is unknown. Here, we provide evidence of intrusions within the crust of the Moon as surface deformations in the form of low-slope lunar domes and floor-fractured craters. All these geological features have morphologies consistent with models of magma spreading at depth and deforming an overlying elastic layer. Furthermore, at floor-fractured craters, the deformation is contained within the crater interior, suggesting that the overpressure at the origin of magma ascent and intrusion was less than the pressure due to the weight of the crust removed by impact. The pressure release due to material removal by impact is significant over a depth equivalent to the crater radius. Because many of these floor-fractured craters are relatively small, i.e. less than 20 to 30 km in radius, this observation suggests that the magma at the origin of the intrusion was already stored within or just below the crust, in deeper intrusions. Thus, a large fraction of the mantle melt might have stored at depth below or within the light primary crust before reaching shallower layers. And hence, magma intrusions must have had a large influence on the thermal and geological evolution of the

  19. Manned in Situ Confirmation of Lunar Ice

    Science.gov (United States)

    Gerené, S. P. B.; Hummeling, R. W. J.; Ockels, W. J.

    A study is performed to investigate the feasibility of a manned expedition to the Moon using the European Ariane-5 launcher. The primary objective of this lunar mission is to confirm the presence of water at the South-Pole craters. It is believed that these permanently shadowed craters contain water in the form of ice. Secondary objective is to perform lunar surface science and making a first step towards a lunar outpost. Early results show that a minimum of two Ariane-5 launches is required. In this `two Ariane' scenario the first launch will bring a Lunar Landing Vehicle (LLV) into low lunar orbit. The second will launch two astronauts in a Crew Transfer Vehicle into a rendez- vous trajectory with the LLV. Arrived at the Moon, the astronauts will enter the LLV, undock from the CTV and land at the designated site located near the rim of the South-Pole Shackleton crater. The transfer strategy for both spacecraft will be the so-called direct transfer, taking about four days. At arrival the LLV will start mapping the landing site at a ground resolution of one meter. As a consequence of the polar orbit, the CTV has to arrive fourteen days later and surface operations can take about twelve days, accumulating in a total mission-duration of 36 days. 32 days for the CTV and 22 days for the LLV. In case a `two Ariane' flight does not posses sufficient capabilities also a `three Ariane' scenario is developed, in which the LLV is split-up into two stages and launched separately. These two will dock at the Moon forming a descent stage and an ascent stage. The third launch will be a CTV. During surface operations, astronauts will set up a solar power unit, install the sample retrieval system and carry out surface science. Samples of the crater floor will be retrieved by means of a probe or robot guided along a cable suspended over the crater rim. Also, this paper shows the way in which European astronauts can be brought to the Moon for other future missions, like the

  20. Optimized Radiator Geometries for Hot Lunar Thermal Environments

    Science.gov (United States)

    Ochoa, Dustin

    2013-01-01

    The optimum radiator configuration in hot lunar thermal environments is one in which the radiator is parallel to the ground and has no view to the hot lunar surface. However, typical spacecraft configurations have limited real estate available for top-mounted radiators, resulting in a desire to use the spacecraft's vertically oriented sides. Vertically oriented, flat panel radiators will have a large view factor to the lunar surface, and thus will be subjected to significant incident lunar infrared heat. Consequently, radiator fluid temperatures will need to exceed approximately 325 K (assuming standard spacecraft radiator optical properties) in order to provide positive heat rejection at lunar noon. Such temperatures are too high for crewed spacecraft applications in which a heat pump is to be avoided. A recent study of vertically oriented radiator configurations subjected to lunar noon thermal environments led to the discovery of a novel radiator concept that yielded positive heat rejection at lower fluid temperatures. This radiator configuration, called the Intense Thermal Infrared Reflector (ITIR), has exhibited superior performance to all previously analyzed concepts in terms of heat rejection in the lunar noon thermal environment. A key benefit of ITIR is the absence of louvers or other moving parts and its simple geometry (no parabolic shapes). ITIR consists of a specularly reflective shielding surface and a diffuse radiating surface joined to form a horizontally oriented V-shape (shielding surface on top). The point of intersection of these surfaces is defined by two angles, those which define the tilt of each surface with respect to the local horizontal. The optimum set of these angles is determined on a case-by-case basis. The idea assumes minimal conductive heat transfer between shielding and radiating surfaces, and a practical design would likely stack sets of these surfaces on top of one another to reduce radiator thickness.

  1. Molecular gas species in the lunar atmosphere

    International Nuclear Information System (INIS)

    Hoffman, J.H.; Hodges, R.R. Jr.

    1975-01-01

    There is good evidence for the existence of very small amounts of methane, ammonia and carbon dioxide in the very tenuous lunar atmosphere which consists primarily of the rare gases helium, neon and argon. All of these gases, except 40 Ar, originate from solar wind particles which impinge on the lunar surface and are imbedded in the surface material. Here they may form molecules before being released into the atmosphere, or may be released directly, as is the case for rare gases. Evidence for the existence of the molecular gas species is based on the pre-dawn enhancement of the mass peaks attributable to these compounds in the data from the Apollo 17 Lunar Mass Spectrometer. Methane is the most abundant molecular gas but its concentration is exceedingly low, 1 x 10 3 mol cm -3 , slightly less than 36 Ar, whereas the solar wind flux of carbon is approximately 2000 times that of 36 Ar. Several reasons are advanced for the very low concentration of methane in the lunar atmosphere

  2. Human Lunar Destiny: Past, Present, and Future

    Science.gov (United States)

    Fletcher, David

    2002-01-01

    This paper offers conceptual strategy and rationale for returning astronauts to the moon. NASA's historic Apollo program enabled humans to make the first expeditionary voyages to the moon and to gather and return samples back to the earth for further study. To continue exploration of the moon within the next ten to fifteen years, one possible mission concept for returning astronauts using existing launch vehicle infrastructure is presented. During these early lunar missions, expeditionary trips are made to geographical destinations and permanent outposts are established at the lunar south pole. As these missions continue, mining operations begin in an effort to learn how to live off the land. Over time, a burgeoning economy based on mining and scientific activity emerges with the formation of more accommodating settlements and surface infrastructure assets. As lunar activity advances, surface infrastructure assets grow and become more complex, lunar settlements and outposts are established across the globe, travel to and from the moon becomes common place, and commerce between earth and the moon develops and flourishes. Colonization and development of the moon is completed with the construction of underground cities and the establishment of a full range of political, religious, educational, and recreational institutions with a diverse population from all nations of the world. Finally, rationale for diversifying concentrations of humanity throughout earth's neighborhood and the greater solar system is presented.

  3. Surface Deformation Observed by InSAR due to Fluid Injection: a Test Study in the Central U.S.

    Science.gov (United States)

    Deng, F.; Dixon, T. H.

    2017-12-01

    The central and eastern U.S. has undergone a dramatic increase in seismicity over the past few years. Many of these recent earthquakes were likely induced by human activities, with underground fluid injection for oil and gas extraction being one of the main contributors. Surface deformation caused by fluid injection has been captured by GPS and InSAR observations in several areas. For example, surface uplift of up to 10 cm due to CO2 injection between 2007 and 2011 was measured by InSAR at an enhanced oil recovery site in west Texas. We are using Texas and Oklahoma as test areas to analyze the potential relationship between surface deformation, underground fluid injection and induced earthquakes. C-band SAR data from ENVISAT and Sentinel-1, and L-band SAR data from ALOS and ALOS-2 are used to form decade-long time series. Based on the surface deformation derived from the time series InSAR data, subsurface volume change and volumetric strain in an elastic half space are estimated. Seismic data provided by the USGS are used to analyze the spatial and temporal distribution pattern of earthquakes, and the potential link between surface deformation and induced earthquakes. The trigger mechanism will be combined with forward modeling to predict seismicity and assess related hazard for future study.

  4. {sup 53}Mn and {sup 60}Fe measurements in lunar samples by means of accelerator mass spectrometry (AMS)

    Energy Technology Data Exchange (ETDEWEB)

    Fimiani, Leticia; Faestermann, Thomas; Gomez Guzman, Jose Manuel; Hain, Karin; Korschinek, Gunther; Ludwig, Peter [Fakultaet fuer Physik, Technische Universitaet Muenchen, D-85748, Garching (Germany); Herzog, Gregory; Ligon, Bret; Park, Jisun [Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854 (United States); Knie, Klaus [GSI, Planckstrasse 1, D-64291, Darmstadt (Germany); Rugel, Georg [Fakultaet fuer Physik, Technische Universitaet Muenchen, D-85748, Garching (Germany); Forschungszentrum Dresden-Rossendorf, D-01314, Dresden (Germany)

    2012-07-01

    Cook et al, 40th LPSC 1129 (2009) reported a concentration of 14{sup +9}{sub -6} dpm {sup 60}Fe/[kg Ni] (T{sub 1/2}=2.62.10{sup 6}a) in a surface sample of the Apollo 12 12025/8 drive tube. This value is higher than the one expected due to galactic or solar cosmic ray production and may suggest the deposition of supernova debris on the lunar surface about 2 Ma ago. In order to try to reproduce this result, new measurements were made in material from the same core and position. To widen the search for supernova debris, we also analyzed four near-surface samples of lunar drive tube 15008; and one each from the skim, scoop and under-boulder samples 69921/41/61 via AMS in the Maier Leibnitz Laboratorium in Garching, Germany. The measuring technique and the preliminary results are discussed.

  5. Lunar and Vesta Web Portals

    Science.gov (United States)

    Law, E.; JPL Luna Mapping; Modeling Project Team

    2015-06-01

    The Lunar Mapping and Modeling Project offers Lunar Mapping and Modeling Portal (http://lmmp.nasa.gov) and Vesta Trek Portal (http://vestatrek.jpl.nasa.gov) providing interactive visualization and analysis tools to enable users to access mapped Lunar and Vesta data products.

  6. Lunar UV-visible-IR mapping interferometric spectrometer

    Science.gov (United States)

    Smith, W. Hayden; Haskin, L.; Korotev, R.; Arvidson, R.; Mckinnon, W.; Hapke, B.; Larson, S.; Lucey, P.

    1992-01-01

    Ultraviolet-visible-infrared mapping digital array scanned interferometers for lunar compositional surveys was developed. The research has defined a no-moving-parts, low-weight and low-power, high-throughput, and electronically adaptable digital array scanned interferometer that achieves measurement objectives encompassing and improving upon all the requirements defined by the LEXSWIG for lunar mineralogical investigation. In addition, LUMIS provides a new, important, ultraviolet spectral mapping, high-spatial-resolution line scan camera, and multispectral camera capabilities. An instrument configuration optimized for spectral mapping and imaging of the lunar surface and provide spectral results in support of the instrument design are described.

  7. Green Bank Lunar Interferometer for Neutrino Transients: GLINT

    Energy Technology Data Exchange (ETDEWEB)

    Langston, Glen I. [NRAO, P.O. Box 2, Green Bank, WV 24944 (United States)], E-mail: glangsto@nrao.edu; Bradley, Rich [NRAO, 520 Edgemont Rd, Charlottesville, VA 22901 (United States); Hankins, Tim [New Mexico Institute of Mining and Technology, 801 Leroy Place, Socorro, NM 87801 (United States); Mutel, Bob [University of Iowa, 706 Van Allen Hall, Iowa City, IA 52242 (United States)

    2009-06-01

    The Green Bank Lunar Interferometer for Neutrino Transients (GLINT) project is a wide band (0.3-2.6 GHz) interferometric radio array dedicated to observations of transient events. The target is detection of few bright (>2000Jy) short duration (few nano-second) pulses from the lunar regolith. The GLINT project has three goals: (1) Maximize detection of statistically significant pulses originating from the lunar surface. (2) Unambiguously differentiate neutrino pulses from other sources of interference. (3) Localize the direction of the incoming radio pulse resulting from neutrino interactions.

  8. Telecast of Astronauts Armstrong and Aldrin by the Lunar Module

    Science.gov (United States)

    1969-01-01

    Astronauts Neil A. Armstrong (in center) commander; and Edwin E. Aldrin Jr. (on right), lunar module pilot, are seen standing near their Lunar Module in this black and white reproduction taken from a telecast by the Apollo 11 lunar surface television camera during the Apollo 11 extravehicular activity. This picture was made from a televised image received at the Deep Space Network tracking station at Goldstone, California. President Richard M. Nixon had just spoken to the two astronauts by radio and Aldrin, a colonel in the U.S. Air Force, is saluting the president.

  9. A lunar polar expedition

    Science.gov (United States)

    Dowling, Richard; Staehle, Robert L.; Svitek, Tomas

    1992-09-01

    Advanced exploration and development in harsh environments require mastery of basic human survival skill. Expeditions into the lethal climates of Earth's polar regions offer useful lessons for tommorrow's lunar pioneers. In Arctic and Antarctic exploration, 'wintering over' was a crucial milestone. The ability to establish a supply base and survive months of polar cold and darkness made extensive travel and exploration possible. Because of the possibility of near-constant solar illumination, the lunar polar regions, unlike Earth's may offer the most hospitable site for habitation. The World Space Foundation is examining a scenario for establishing a five-person expeditionary team on the lunar north pole for one year. This paper is a status report on a point design addressing site selection, transportation, power, and life support requirements.

  10. Simulations of Water Migration in the Lunar Exosphere

    Science.gov (United States)

    Hurley, D.; Benna, M.; Mahaffy, P. R.; Elphic, R. C.; Goldstein, D. B.

    2014-12-01

    We perform modeling and analysis of water in the lunar exosphere. There were two controlled experiments of water interactions with the surface of the Moon observed by the Lunar Atmosphere and Dust Environment Explorer (LADEE) Neutral Mass Spectrometer (NMS). The Chang'e 3 landing on the Moon on 14 Dec 2013 putatively sprayed ~120 kg of water on the surface on the Moon at a mid-morning local time. Observations by LADEE near the noon meridian on six of the orbits in the 24 hours following the landing constrain the propagation of water vapor. Further, on 4 Apr 2014, LADEE's Orbital Maintenance Manuever (OMM) #21 sprayed the surface of the Moon with an estimated 0.73 kg of water in the pre-dawn sector. Observations of this maneuver and later in the day constrain the adsorption and release at dawn of adsorbed materials. Using the Chang'e 3 exhaust plume and LADEE's OMM-21 as control experiments, we set limits to the adsorption and thermalization of water with lunar regolith. This enables us to predict the efficiency of the migration of water as a delivery mechanism to the lunar poles. Then we simulate the migration of water through the lunar exosphere using the rate of sporadic inputs from meteoritic sources (Benna et al., this session). Simulations predict the amount of water adsorbed to the surface of the Moon and the effective delivery rate to the lunar polar cold traps.

  11. Remote Assessment of Lunar Resource Potential

    Science.gov (United States)

    Taylor, G. Jeffrey

    1992-01-01

    Assessing the resource potential of the lunar surface requires a well-planned program to determine the chemical and mineralogical composition of the Moon's surface at a range of scales. The exploration program must include remote sensing measurements (from both Earth's surface and lunar orbit), robotic in situ analysis of specific places, and eventually, human field work by trained geologists. Remote sensing data is discussed. Resource assessment requires some idea of what resources will be needed. Studies thus far have concentrated on oxygen and hydrogen production for propellant and life support, He-3 for export as fuel for nuclear fusion reactors, and use of bulk regolith for shielding and construction materials. The measurement requirements for assessing these resources are given and discussed briefly.

  12. High-Resolution Spectroscopic Observations of Potassium Emissions in the Lunar Exosphere

    Science.gov (United States)

    Robertson, Sarena D.; Oliversen, Ronald J.; Mierkiewicz, Edwin J.; Kuruppuaratchi, Dona Chathuni P.; Derr, Nicholas James; Gallant, Margaret A.; McFarland, Christina G.; Sarantos, Menelaos

    2018-01-01

    We investigate lunar exospheric potassium D1 emissions (7698.9646 Å) using high-resolution (R = 180,000 or 1.7 km/s) spectroscopy with our dual-etalon Fabry-Perot instrument to measure line widths and radial velocities. The Field of View (FOV) is 2 arcmins (~224 km at the mean lunar distance of 384,400 km) positioned tangent to the sunlit limb. The FOV placements are at cardinal directions from a variety of reference craters. All observations are collected at the National Solar Observatory McMath-Pierce Telescope in Kitt Peak, Arizona. The data are from several observations from 2014 through 2017 at various times of the year. Results are produced via a newly created automated data reduction using Python. Python was chosen as an open-source alternative to the previously used IDL and MATLAB scripts to decrease the cost of software licenses and maintenance. The potassium spectral line profiles provide a direct method to track exospheric effective temperatures and velocities. By monitoring the state of the potassium emissions over different lunar phases, solar activity, and the influx of meteor streams, we can constrain physical processes of sources and sinks at the lunar surface. Mechanisms that create the exosphere include photon-stimulated desorption, thermal evaporation, meteoroid impact vaporization, and ion sputtering via solar wind. In contrast, the exosphere is diminished due to the low lunar escape velocity, solar radiation pressure, and neutral gas being ionized and swept away by the interplanetary and terrestrial magnetic field. Preliminary analysis of 2017 data (January through June, excluding February) indicates an average potassium temperature of 1140 K but varying over the range of 550 K to 2000 K. Preliminary results from 2014 data depict a similar range of temperatures to that of 2017. Further analysis is expected for additional data from 2014 to later observations in 2017 that were not included in the initial set of models.

  13. 3D-Laser-Scanning Technique Applied to Bulk Density Measurements of Apollo Lunar Samples

    Science.gov (United States)

    Macke, R. J.; Kent, J. J.; Kiefer, W. S.; Britt, D. T.

    2015-01-01

    In order to better interpret gravimetric data from orbiters such as GRAIL and LRO to understand the subsurface composition and structure of the lunar crust, it is import to have a reliable database of the density and porosity of lunar materials. To this end, we have been surveying these physical properties in both lunar meteorites and Apollo lunar samples. To measure porosity, both grain density and bulk density are required. For bulk density, our group has historically utilized sub-mm bead immersion techniques extensively, though several factors have made this technique problematic for our work with Apollo samples. Samples allocated for measurement are often smaller than optimal for the technique, leading to large error bars. Also, for some samples we were required to use pure alumina beads instead of our usual glass beads. The alumina beads were subject to undesirable static effects, producing unreliable results. Other investigators have tested the use of 3d laser scanners on meteorites for measuring bulk volumes. Early work, though promising, was plagued with difficulties including poor response on dark or reflective surfaces, difficulty reproducing sharp edges, and large processing time for producing shape models. Due to progress in technology, however, laser scanners have improved considerably in recent years. We tested this technique on 27 lunar samples in the Apollo collection using a scanner at NASA Johnson Space Center. We found it to be reliable and more precise than beads, with the added benefit that it involves no direct contact with the sample, enabling the study of particularly friable samples for which bead immersion is not possible

  14. Hazard Detection Software for Lunar Landing

    Science.gov (United States)

    Huertas, Andres; Johnson, Andrew E.; Werner, Robert A.; Montgomery, James F.

    2011-01-01

    The Autonomous Landing and Hazard Avoidance Technology (ALHAT) Project is developing a system for safe and precise manned lunar landing that involves novel sensors, but also specific algorithms. ALHAT has selected imaging LIDAR (light detection and ranging) as the sensing modality for onboard hazard detection because imaging LIDARs can rapidly generate direct measurements of the lunar surface elevation from high altitude. Then, starting with the LIDAR-based Hazard Detection and Avoidance (HDA) algorithm developed for Mars Landing, JPL has developed a mature set of HDA software for the manned lunar landing problem. Landing hazards exist everywhere on the Moon, and many of the more desirable landing sites are near the most hazardous terrain, so HDA is needed to autonomously and safely land payloads over much of the lunar surface. The HDA requirements used in the ALHAT project are to detect hazards that are 0.3 m tall or higher and slopes that are 5 or greater. Steep slopes, rocks, cliffs, and gullies are all hazards for landing and, by computing the local slope and roughness in an elevation map, all of these hazards can be detected. The algorithm in this innovation is used to measure slope and roughness hazards. In addition to detecting these hazards, the HDA capability also is able to find a safe landing site free of these hazards for a lunar lander with diameter .15 m over most of the lunar surface. This software includes an implementation of the HDA algorithm, software for generating simulated lunar terrain maps for testing, hazard detection performance analysis tools, and associated documentation. The HDA software has been deployed to Langley Research Center and integrated into the POST II Monte Carlo simulation environment. The high-fidelity Monte Carlo simulations determine the required ground spacing between LIDAR samples (ground sample distances) and the noise on the LIDAR range measurement. This simulation has also been used to determine the effect of

  15. Sources and Transportation of Bulk, Low-Cost Lunar Simulant Materials

    Science.gov (United States)

    Rickman, D. L.

    2013-01-01

    Marshall Space Flight Center (MSFC) has built the Lunar Surface Testbed using 200 tons of volcanic cinder and ash from the same source used for the simulant series JSC-1. This Technical Memorandum examines the alternatives examined for transportation and source. The cost of low-cost lunar simulant is driven by the cost of transportation, which is controlled by distance and, to a lesser extent, quantity. Metabasalts in the eastern United States were evaluated due to their proximity to MSFC. Volcanic cinder deposits in New Mexico, Colorado, and Arizona were recognized as preferred sources. In addition to having fewer green, secondary minerals, they contain vesicular glass, both of which are desirable. Transportation costs were more than 90% of the total procurement costs for the simulant material.

  16. Searching for Lunar Horizon Glow With the Lunar Orbiter Laser Altimeter (LOLA)

    Science.gov (United States)

    Barker, M. K.; Mazarico, E. M.; McClanahan, T. P.; Sun, X.; Smith, D. E.; Neumann, G. A.; Zuber, M. T.; Head, J. W., III

    2017-12-01

    The dust environment of the Moon is sensitive to the interplanetary meteoroid population and dust transport processes near the lunar surface, and this affects many aspects of lunar surface science and planetary exploration. The interplanetary meteoroid population poses a significant risk to spacecraft, yet it remains one of the more uncertain constituents of the space environment. Observed and hypothesized lunar dust transport mechanisms have included impact-generated dust plumes, electrostatic levitation, and dynamic lofting. Many details of the impactor flux and impact ejection process are poorly understood, a fact highlighted by recent discrepant estimates of the regolith mixing rate. Apollo-era observations of lunar horizon glow (LHG) were interpreted as sunlight forward-scattered by exospheric dust grains levitating in the top meter above the surface or lofted to tens of kilometers in altitude. However, recent studies have placed limits on the dust density orders of magnitude less than what was originally inferred, raising new questions on the time variability of the dust environment. Motivated by the need to better understand dust transport processes and the meteoroid population, the Lunar Orbiter Laser Altimeter (LOLA) aboard the Lunar Reconnaissance Orbiter (LRO) is conducting a campaign to search for LHG with the LOLA Laser Ranging (LR) system. Advantages of this LOLA LHG search include: (1) the LOLA-LR telescope can observe arbitrarily close to the Sun at any time during the year without damaging itself or the other instruments, (2) a long temporal baseline with observations both during and outside of meteor streams, which will improve the chances of detecting LHG, and (3) a focus on altitudes methodology, and preliminary results.

  17. When did the lunar core dynamo cease?

    Science.gov (United States)

    Tikoo, S. M.; Weiss, B. P.; Shuster, D. L.; Fuller, M.

    2013-12-01

    Remanent magnetization in the lunar crust and in returned Apollo samples has long suggested that the Moon formed a metallic core and an ancient dynamo magnetic field. Recent paleomagnetic investigations of lunar samples demonstrate that the Moon had a core dynamo which produced ~30-110 μT surface fields between at least 4.2 and 3.56 billion years ago (Ga). Tikoo et al. (1) recently found that the field declined to below several μT by 3.19 Ga. However, given that even values of a few μT are at the upper end of the intensities predicted by dynamo theory for this late in lunar history, it remains uncertain when the lunar dynamo actually ceased completely. Determining this requires a young lunar rock with extraordinarily high magnetic recording fidelity. With this goal, we are conducting a new analysis of young regolith breccia 15498. Although the breccia's age is currently uncertain, the presence of Apollo 15-type mare basalt clasts provides an upper limit constraint of ~3.3 Ga, while trapped Ar data suggest a lithification age of ~1.3 Ga. In stark contrast to the multidomain character of virtually all lunar crystalline rocks, the magnetic carriers in 15498 are on average pseudo-single domain to superparamagnetic, indicating that the sample should provide high-fidelity paleointensity records. A previous alternating field (AF) and thermal demagnetization study of 15498 by Gose et al. (2) observed that the sample carries stable remanent magnetization which persists to unblocking temperatures of at least 650°C. Using a modified Thellier technique, they reported a paleointensity of 2 μT. Although this value may have been influenced by spurious remanence acquired during pretreatment with AF demagnetization, our results confirm the presence of an extremely stable (blocked to coercivities >290 mT) magnetization in the glassy matrix. We also found that this magnetization is largely unidirectional across mutually oriented subsamples. The cooling timescale of this rock (~1

  18. Detecting Volatiles Deep in the Lunar Regolith

    Science.gov (United States)

    Crotts, A.; Heggy, E.; Ciarletti, V.; Colaprete, A.; Moghaddam, M.; Siegler, M. A.

    2015-12-01

    There is increasing theoretical and empirical evidence, from the Apollo era and after, of volatiles deep in the lunar interior, in the crust and deeper, both hydrogen-rich and otherwise. This comes in the form of fire fountain samples from Apollo 15 and Apollo 17, of hydrated minerals excavated by impacts which reach the base of the lunar crust e.g., crater Bullialdus, of hydration of apatite and other minerals, as well as predictions of a water-concentrated layer along with the KREEP material at the base of the lunar crust. We discuss how the presence of these volatiles might be directly explored. In particular water vapor molecules percolating to the surface through lunar regolith might be expected to stick and freeze into the regolith, at depths of several meters depending on the regolith temperature profile, porosity and particle size distribution, quantities that are not well known beyond two meters depth. To explore these depths in the regolith we use and propose several modes of penetrating radar. We will present results using the SELENE/Kaguya's Lunar Sounding RADAR (LSR) to probe the bulk volatile dielectric and loss structure properties of the regolith in various locations, both within permanently shadowed regions (PSRs) and without, and within neutron suppression regions (NSRs) as traced by epithermal neutrons and without. We also propose installation of ground penetrating RADAR (GPR) on a roving lunar platform that should be able to probe between 0.2 and 1.6 GHz, which will provide a probe of the entire depth of the lunar regolith as well as a high-resolution (about 4 cm FWHM) probe of the upper meter or two of the lunar soil, where other probes of volatiles such as epithermal neutron absorption or drilling might be employed. We discuss predictions for what kinds of volatile density profiles might be distinguished in this way, and whether these will be detected from orbit as NSRs, whether these must be restricted to PSRs, and how these might appear in

  19. Lunar Riometry: Proof-of-Concept Instrument Package

    Science.gov (United States)

    Lazio, J.; Jones, D. L.; MacDowall, R. J.; Stewart, K.; Giersch, L.; Burns, J. O.; Farrell, W. M.; Kasper, J. C.; O'Dwyer, I.; Hartman, J.

    2012-12-01

    The lunar exosphere is the exemplar of a plasma near the surface of an airless body. Exposed to both the solar and interstellar radiation fields, the lunar exosphere is mostly ionized, and enduring questions regarding its properties include its density and vertical extent, the extent of contributions from volatile outgassing from the Moon, and its behavior over time, including response to the solar wind and modification by landers. Relative ionospheric measurements (riometry) is based on the simple physical principle that electromagnetic waves cannot propagate through a partially or fully ionized medium below the plasma frequency, and riometers have been deployed on the Earth in numerous remote and hostile environments. A multi-frequency riometer on the lunar surface would be able to monitor, in situ, the vertical extent of the lunar exosphere over time. We describe a concept for a riometer implemented as a secondary science payload on future lunar landers, such as those recommended in the recent Planetary Sciences Decadal Survey report. The instrument concept is simple, consisting of an antenna implemented as a metal deposited on polyimide film and receiver. We illustrate various deployment mechanisms and performance of a prototype in increasing lunar analog conditions. While the prime mission of such a riometer would be probing the lunar exosphere, our concept would also be capable to measuring the properties of dust impactors. The Lunar University Network for Astrophysical Research consortium is funded by the NASA Lunar Science Institute to investigate concepts for astrophysical observatories on the Moon. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA.

  20. NASA Lunar Mining and Construction Activities and Plans

    Science.gov (United States)

    Sanders, Gerald B.; Larson, William E.; Sacksteder, Kurt R.

    2009-01-01

    The Space Exploration Policy enacted by the US Congress in 2005 calls for the US National Aeronautics and Space Administration (NASA) to implement a sustained and affordable human and robotic program to explore the solar system and beyond; Extend human presence across the solar system, starting with a human return to the Moon by the year 2020, in preparation for human exploration of Mars and other destinations; Develop the innovative technologies, knowledge, and infrastructures both to explore and to support decisions about the destinations for human exploration; and Promote international and commercial participation in exploration to further U.S. scientific, security, and economic interests. In 2006, NASA released the Lunar Architecture Study, which proposed establishing a lunar Outpost on the Moon with international participation to extend human presence beyond Earth's orbit, pursue scientific activities, use the Moon to prepare for future human missions to Mars, and expand Earth s economic sphere. The establishment of sustained human presence on the Moon for science and exploration combines the design, integration, and operation challenges experienced from both the short Apollo lunar missions and the build-up and sustained crew operations of the International Space Station (ISS). Apollo experience reminds developers and mission planners that hardware must operate under extremely harsh environmental and abrasive conditions and every kilogram of mass and payload must be critical to achieve the mission s objectives due to the difficulty and cost of reaching the lunar surface. Experience from the ISS reminds developers and mission planners that integration of all hardware must be designed and planned from the start of the program, operations and evolution of capabilities on a continuous basis are important, and long-term life-cycle costs and logistical needs are equally or more important than minimizing early development and test costs. Overarching all of this is

  1. On the history of the early meteoritic bombardment of the Moon: Was there a terminal lunar cataclysm?

    Science.gov (United States)

    Michael, Greg; Basilevsky, Alexander; Neukum, Gerhard

    2018-03-01

    the considered histograms and relative probability plots not only the 3.87 Ga peak (due to Imbrium basin), but also several secondary peaks caused by the formation of other basins distributed between 3.87 and 4.25 Ga. The lunar terminal cataclysm hypothesis is in disagreement with the distribution of K-Ar ages for the highland rocks of the lunar meteorites. The population of lunar meteorites representing localities randomly distributed over the lunar surface, and thus free from the mentioned sampling bias, shows no ∼3.9 Ga peak as it should, if the cataclysm did occur. We conclude that the statistics of sample ages contradict the terminal cataclysm scenario in the bombardment of the Moon. We also see evidence for the formation of several impact basins between 3.87 and 4.25 Ga which is likewise incompatible with the hypothesis of a short interval cataclysm. There remain other basins, including the largest South Pole - Aitken, the ages of which should be determined in future studies to further clarify the impact history. Sample-return missions targeted to date several key basins need to be planned, and the continued study of lunar meteorites may also bring new details to the general view of the impact bombardment of the Moon.

  2. Robotic Lunar Lander Development Status

    Science.gov (United States)

    Ballard, Benjamin; Cohen, Barbara A.; McGee, Timothy; Reed, Cheryl

    2012-01-01

    NASA Marshall Space Flight Center and John Hopkins University Applied Physics Laboratory have developed several mission concepts to place scientific and exploration payloads ranging from 10 kg to more than 200 kg on the surface of the moon. The mission concepts all use a small versatile lander that is capable of precision landing. The results to date of the lunar lander development risk reduction activities including high pressure propulsion system testing, structure and mechanism development and testing, and long cycle time battery testing will be addressed. The most visible elements of the risk reduction program are two fully autonomous lander flight test vehicles. The first utilized a high pressure cold gas system (Cold Gas Test Article) with limited flight durations while the subsequent test vehicle, known as the Warm Gas Test Article, utilizes hydrogen peroxide propellant resulting in significantly longer flight times and the ability to more fully exercise flight sensors and algorithms. The development of the Warm Gas Test Article is a system demonstration and was designed with similarity to an actual lunar lander including energy absorbing landing legs, pulsing thrusters, and flight-like software implementation. A set of outdoor flight tests to demonstrate the initial objectives of the WGTA program was completed in Nov. 2011, and will be discussed.

  3. Experimental study of heat transfer enhancement due to the surface vibrations in a flexible double pipe heat exchanger

    Science.gov (United States)

    Hosseinian, A.; Meghdadi Isfahani, A. H.

    2018-04-01

    In this study, the heat transfer enhancement due to the surface vibration for a double pipe heat exchanger, made of PVDF, is investigated. In order to create forced vibrations (3-9 m/s2, 100 Hz) on the outer surface of the heat exchanger electro-dynamic vibrators are used. Experiments were performed at inner Reynolds numbers ranging from 2533 to 9960. The effects of volume flow rate and temperature on heat transfer performance are evaluated. Results demonstrated that heat transfer coefficient increases by increasing vibration level and mass flow rate. The most increase in heat transfer coefficient is 97% which is obtained for the highest vibration level (9 m/s2) in the experiment range.

  4. Detection of the lunar body tide by the Lunar Orbiter Laser Altimeter.

    Science.gov (United States)

    Mazarico, Erwan; Barker, Michael K; Neumann, Gregory A; Zuber, Maria T; Smith, David E

    2014-04-16

    The Lunar Orbiter Laser Altimeter instrument onboard the Lunar Reconnaissance Orbiter spacecraft collected more than 5 billion measurements in the nominal 50 km orbit over ∼10,000 orbits. The data precision, geodetic accuracy, and spatial distribution enable two-dimensional crossovers to be used to infer relative radial position corrections between tracks to better than ∼1 m. We use nearly 500,000 altimetric crossovers to separate remaining high-frequency spacecraft trajectory errors from the periodic radial surface tidal deformation. The unusual sampling of the lunar body tide from polar lunar orbit limits the size of the typical differential signal expected at ground track intersections to ∼10 cm. Nevertheless, we reliably detect the topographic tidal signal and estimate the associated Love number h 2 to be 0.0371 ± 0.0033, which is consistent with but lower than recent results from lunar laser ranging. Altimetric data are used to create radial constraints on the tidal deformationThe body tide amplitude is estimated from the crossover dataThe estimated Love number is consistent with previous estimates but more precise.

  5. TRANSIENT LUNAR PHENOMENA: REGULARITY AND REALITY

    International Nuclear Information System (INIS)

    Crotts, Arlin P. S.

    2009-01-01

    Transient lunar phenomena (TLPs) have been reported for centuries, but their nature is largely unsettled, and even their existence as a coherent phenomenon is controversial. Nonetheless, TLP data show regularities in the observations; a key question is whether this structure is imposed by processes tied to the lunar surface, or by terrestrial atmospheric or human observer effects. I interrogate an extensive catalog of TLPs to gauge how human factors determine the distribution of TLP reports. The sample is grouped according to variables which should produce differing results if determining factors involve humans, and not reflecting phenomena tied to the lunar surface. Features dependent on human factors can then be excluded. Regardless of how the sample is split, the results are similar: ∼50% of reports originate from near Aristarchus, ∼16% from Plato, ∼6% from recent, major impacts (Copernicus, Kepler, Tycho, and Aristarchus), plus several at Grimaldi. Mare Crisium produces a robust signal in some cases (however, Crisium is too large for a 'feature' as defined). TLP count consistency for these features indicates that ∼80% of these may be real. Some commonly reported sites disappear from the robust averages, including Alphonsus, Ross D, and Gassendi. These reports begin almost exclusively after 1955, when TLPs became widely known and many more (and inexperienced) observers searched for TLPs. In a companion paper, we compare the spatial distribution of robust TLP sites to transient outgassing (seen by Apollo and Lunar Prospector instruments). To a high confidence, robust TLP sites and those of lunar outgassing correlate strongly, further arguing for the reality of TLPs.

  6. Lunar base thermoelectric power station study

    Science.gov (United States)

    Determan, William; Frye, Patrick; Mondt, Jack; Fleurial, Jean-Pierre; Johnson, Ken; Stapfer, G.; Brooks, Michael D.; Heshmatpour, Ben

    2006-01-01

    Under NASA's Project Prometheus, the Nuclear Systems Program, the Jet Propulsion Laboratory, Pratt & Whitney Rocketdyne, and Teledyne Energy Systems have teamed with a number of universities, under the Segmented Thermoelectric Multicouple Converter (STMC) program, to develop the next generation of advanced thermoelectric converters for space reactor power systems. Work on the STMC converter assembly has progressed to the point where the lower temperature stage of the segmented multicouple converter assembly is ready for laboratory testing and the upper stage materials have been identified and their properties are being characterized. One aspect of the program involves mission application studies to help define the potential benefits from the use of these STMC technologies for designated NASA missions such as the lunar base power station where kilowatts of power are required to maintain a permanent manned presence on the surface of the moon. A modular 50 kWe thermoelectric power station concept was developed to address a specific set of requirements developed for this mission. Previous lunar lander concepts had proposed the use of lunar regolith as in-situ radiation shielding material for a reactor power station with a one kilometer exclusion zone radius to minimize astronaut radiation dose rate levels. In the present concept, we will examine the benefits and requirements for a hermetically-sealed reactor thermoelectric power station module suspended within a man-made lunar surface cavity. The concept appears to maximize the shielding capabilities of the lunar regolith while minimizing its handling requirements. Both thermal and nuclear radiation levels from operation of the station, at its 100-m exclusion zone radius, were evaluated and found to be acceptable. Site preparation activities are reviewed and well as transport issues for this concept. The goal of the study was to review the entire life cycle of the unit to assess its technical problems and technology

  7. The Sooner Lunar Schooner: Lunar engineering education

    Science.gov (United States)

    Miller, D. P.; Hougen, D. F.; Shirley, D.

    2003-06-01

    The Sooner Lunar Schooner is a multi-disciplinary ongoing project at the University of Oklahoma to plan, design, prototype, cost and (when funds become available) build/contract and fly a robotic mission to the Moon. The goal of the flight will be to explore a small section of the Moon; conduct a materials analysis of the materials left there by an Apollo mission thirty years earlier; and to perform a selenographic survey of areas that were too distant or considered too dangerous to be done by the Apollo crew. The goal of the Sooner Lunar Schooner Project is to improve the science and engineering educations of the hundreds of undergraduate and graduate students working on the project. The participants, while primarily from engineering and physics, will also include representatives from business, art, journalism, law and education. This project ties together numerous existing research programs at the University, and provides a framework for the creation of many new research proposals. The authors were excited and motivated by the Apollo missions to the Moon. When we asked what we could do to similarly motivate students we realized that nothing is as exciting as going to the Moon. The students seem to agree.

  8. Synthesis and Stability of Iron Nanoparticles for Lunar Environment Studies

    Science.gov (United States)

    Hung, Ching-cheh; McNatt, Jeremiah

    2009-01-01

    Simulant of lunar dust is needed when researching the lunar environment. However, unlike the true lunar dust, today s simulants do not contain nanophase iron. Two different processes have been developed to fabricate nanophase iron to be used as part of the lunar dust simulant: (1) Sequentially treating a mixture of ferric chloride, fluorinated carbon, and soda lime glass beads at about 300 C in nitrogen, at room temperature in air, and then at 1050 C in nitrogen. The product includes glass beads that are grey in color, can be attracted by a magnet, and contain alpha-iron nanoparticles (which seem to slowly lose their lattice structure in ambient air during a period of 12 months). This product may have some similarity to the lunar glassy regolith that contains Fe(sup 0). (2) Heating a mixture of carbon black and a lunar simulant (a mixed metal oxide that includes iron oxide) at 1050 C in nitrogen. This process simulates lunar dust reaction to the carbon in a micrometeorite at the time of impact. The product contains a chemically modified simulant that can be attracted by a magnet and has a surface layer whose iron concentration increased during the reaction. The iron was found to be alpha-iron and Fe3O4 nanoparticles, which appear to grow after the fabrication process, but stabilizes after 6 months of ambient air storage.

  9. The lunar thermal ice pump

    Energy Technology Data Exchange (ETDEWEB)

    Schorghofer, Norbert [Institute for Astronomy and NASA Astrobiology Institute, University of Hawaii, Honolulu, HI 96822 (United States); Aharonson, Oded, E-mail: norbert@hawaii.edu [Helen Kimmel Center for Planetary Science, Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot, 76100 (Israel)

    2014-06-20

    It has long been suggested that water ice can exist in extremely cold regions near the lunar poles, where sublimation loss is negligible. The geographic distribution of H-bearing regolith shows only a partial or ambiguous correlation with permanently shadowed areas, thus suggesting that another mechanism may contribute to locally enhancing water concentrations. We show that under suitable conditions, water molecules can be pumped down into the regolith by day-night temperature cycles, leading to an enrichment of H{sub 2}O in excess of the surface concentration. Ideal conditions for pumping are estimated and found to occur where the mean surface temperature is below 105 K and the peak surface temperature is above 120 K. These conditions complement those of the classical cold traps that are roughly defined by peak temperatures lower than 120 K. On the present-day Moon, an estimated 0.8% of the global surface area experiences such temperature variations. Typically, pumping occurs on pole-facing slopes in small areas, but within a few degrees of each pole the equator-facing slopes are preferred. Although pumping of water molecules is expected over cumulatively large areas, the absolute yield of this pump is low; at best, a few percent of the H{sub 2}O delivered to the surface could have accumulated in the near-surface layer in this way. The amount of ice increases with vapor diffusivity and is thus higher in the regolith with large pore spaces.

  10. Kickstarting a New Era of Lunar Industrialization via Campaign of Lunar COTS Missions

    Science.gov (United States)

    Zuniga, Allison F.; Turner, Mark; Rasky, Daniel; Pittman, Robert B.; Zapata, Edgar

    2016-01-01

    To support the goals of expanding our human presence and current economic sphere beyond LEO, a new plan was constructed for NASA to enter into partnerships with industry to foster and incentivize a new era of lunar industrialization. For NASA to finally be successful in achieving sustainable human exploration missions beyond LEO, lessons learned from our space history have shown that it is essential for current program planning to include affordable and economic development goals as well as address top national priorities to obtain much needed public support. In the last 58 years of NASA's existence, only Apollo's human exploration missions beyond LEO were successful since it was proclaimed to be a top national priority during the 1960's. However, the missions were not sustainable and ended abruptly in 1972 due to lack of funding and insufficient economic gain. Ever since Apollo, there have not been any human missions beyond LEO because none of the proposed program plans were economical or proclaimed a top national priority. The proposed plan outlines a new campaign of low-cost, commercial-enabled lunar COTS (Commercial Orbital Transfer Services) missions which is an update to the Lunar COTS plan previously described. The objectives of this new campaign of missions are to prospect for resources, determine the economic viability of extracting those resources and assess the value proposition of using these resources in future exploration architectures such as Mars. These missions would be accomplished in partnership with commercial industry using the wellproven COTS Program acquisition model. This model proved to be very beneficial to both NASA and its industry partners as NASA saved significantly in development and operational costs, as much as tenfold, while industry partners successfully expanded their market share and demonstrated substantial economic gain. Similar to COTS, the goals for this new initiative are 1) to develop and demonstrate cost-effective, cis-lunar

  11. Toxicity of lunar dust

    NARCIS (Netherlands)

    Linnarsson, D.; Carpenter, J.; Fubini, B.; Gerde, P.; Loftus, D.; Prisk, K.; Staufer, U.; Tranfield, E.; van Westrenen, W.

    2012-01-01

    The formation, composition and physical properties of lunar dust are incompletely characterised with regard to human health. While the physical and chemical determinants of dust toxicity for materials such as asbestos, quartz, volcanic ashes and urban particulate matter have been the focus of

  12. Lunar Phases Planisphere

    Science.gov (United States)

    Shawl, Stephen J.

    2010-01-01

    This paper describes a lunar phases planisphere with which a user can answer questions about the rising and setting times of the Moon as well as questions about where the Moon will be at a given phase and time. The article contains figures that can be photocopied to make the planisphere. (Contains 2 figures.)

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

    Science.gov (United States)

    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 lunar regolith simulant such as cell membrane damage, induction of oxidative stress and proinflammatory effect.

  14. Free Space Laser Communication Experiments from Earth to the Lunar Reconnaissance Orbiter in Lunar Orbit

    Science.gov (United States)

    Sun, Xiaoli; Skillman, David R.; Hoffman, Evan D.; Mao, Dandan; McGarry, Jan F.; Zellar, Ronald S.; Fong, Wai H; Krainak, Michael A.; Neumann, Gregory A.; Smith, David E.

    2013-01-01

    Laser communication and ranging experiments were successfully conducted from the satellite laser ranging (SLR) station at NASA Goddard Space Flight Center (GSFC) to the Lunar Reconnaissance Orbiter (LRO) in lunar orbit. The experiments used 4096-ary pulse position modulation (PPM) for the laser pulses during one-way LRO Laser Ranging (LR) operations. Reed-Solomon forward error correction codes were used to correct the PPM symbol errors due to atmosphere turbulence and pointing jitter. The signal fading was measured and the results were compared to the model.

  15. Indigenous lunar construction materials

    Science.gov (United States)

    Rogers, Wayne P.; Sture, Stein

    1991-01-01

    The utilization of local resources for the construction and operation of a lunar base can significantly reduce the cost of transporting materials and supplies from Earth. The feasibility of processing lunar regolith to form construction materials and structural components is investigated. A preliminary review of potential processing methods such as sintering, hot-pressing, liquification, and cast basalt techniques, was completed. The processing method proposed is a variation on the cast basalt technique. It involves liquification of the regolith at 1200-1300 C, casting the liquid into a form, and controlled cooling. While the process temperature is higher than that for sintering or hot-pressing (1000-1100 C), this method is expected to yield a true engineering material with low variability in properties, high strength, and the potential to form large structural components. A scenario for this processing method was integrated with a design for a representative lunar base structure and potential construction techniques. The lunar shelter design is for a modular, segmented, pressurized, hemispherical dome which could serve as habitation and laboratory space. Based on this design, estimates of requirements for power, processing equipment, and construction equipment were made. This proposed combination of material processing method, structural design, and support requirements will help to establish the feasibility of lunar base construction using indigenous materials. Future work will refine the steps of the processing method. Specific areas where more information is needed are: furnace characteristics in vacuum; heat transfer during liquification; viscosity, pouring and forming behavior of molten regolith; design of high temperature forms; heat transfer during cooling; recrystallization of basalt; and refinement of estimates of elastic moduli, compressive and tensile strength, thermal expansion coefficient, thermal conductivity, and heat capacity. The preliminary

  16. Behavior of surface residual stress in explosion hardened high manganese austenitic cast steel due to repeated impact loads

    International Nuclear Information System (INIS)

    Oda, Akira; Miyagawa, Hideaki

    1985-01-01

    Explosion hardened high manganese austenitic cast steel is being tried for rail crossing recently. From the previous studies, it became clear that high tensile residual stress was generated in the hardened surface layer by explosion and microcracks were observed. In this study, therefore, the behavior of surface residual stress in explosion hardened steel due to repeated impact loads was examined and compared with those of the original and shot peened steels. The results obtained are summarized as follows: (1) In the initial stage of the repetition of impact, high tensile surface residual stress in explosion hardened steel decreased rapidly with the repetition of impact, while those of the original and shot peened steels increased rapidly. This difference was attributed to the difference in depth of the work hardened layer in three testing materials. (2) Beyond 20 impacts the residual stress of three test specimens decreased gradually, and at more than 2000 impacts the compressive stress of about 500 MPa was produced regardless of the histories of working of testing materials. (3) The linear law in the second stage of residual stress fading was applicable to this case, and the range of the linear relationship was related to the depth of the work hardened layer of testing material. (4) From the changes in half-value breadth and peak intensity of diffraction X-ray, it was supposed that a peculiar microscopic strain exists in explosion hardened steel. (author)

  17. Lunar Penetrating Radar onboard the Chang'e-3 mission

    International Nuclear Information System (INIS)

    Fang Guang-You; Zhou Bin; Ji Yi-Cai; Zhang Qun-Ying; Shen Shao-Xiang; Li Yu-Xi; Guan Hong-Fei; Tang Chuan-Jun; Gao Yun-Ze; Lu Wei; Ye Sheng-Bo; Han Hai-Dong; Zheng Jin; Wang Shu-Zhi

    2014-01-01

    Lunar Penetrating Radar (LPR) is one of the important scientific instruments onboard the Chang'e-3 spacecraft. Its scientific goals are the mapping of lunar regolith and detection of subsurface geologic structures. This paper describes the goals of the mission, as well as the basic principles, design, composition and achievements of the LPR. Finally, experiments on a glacier and the lunar surface are analyzed

  18. Telecast of Astronauts Armstrong and Aldrin by the Lunar Module ladder

    Science.gov (United States)

    1969-01-01

    Astronauts Neil A. Armstrong (on left), commander; and Edwin E. Aldrin Jr., lunar module pilot, are seen standing by the Lunar Module ladder in this black and white reproduction taken from a telecast by the Apollo 11 lunar surface television camera during the Apollo 11 extravehicular activity. This picture was made from a televised image received at the Deep Space Network tracking station at Goldstone, California.

  19. Overturn of magma ocean ilmenite cumulate layer: Implications for lunar magmatic evolution and formation of a lunar core

    Science.gov (United States)

    Hess, P. C.; Parmentier, E. M.

    1993-01-01

    We explore a model for the chemical evolution of the lunar interior that explains the origin and evolution of lunar magmatism and possibly the existence of a lunar core. A magma ocean formed during accretion differentiates into the anorthositic crust and chemically stratified cumulate mantle. The cumulative mantle is gravitationally unstable with dense ilmenite cumulate layers overlying olivine-orthopyroxene cumulates with Fe/Mg that decreases with depth. The dense ilmenite layer sinks to the center of the moon forming the core. The remainder of the gravitationally unstable cumulate pile also overturns. Any remaining primitive lunar mantle rises to its level of neutral buoyancy in the cumulate pile. Perhaps melting of primitive lunar mantle due to this decompression results in early lunar Mg-rich magmatism. Because of its high concentration of incompatible heat producing elements, the ilmenite core heats the overlying orthopyroxene-bearing cumulates. As a conductively thickening thermal boundary layer becomes unstable, the resulting mantle plumes rise, decompress, and partially melt to generate the mare basalts. This model explains both the timing and chemical characteristics of lunar magmatism.

  20. The International Lunar Decade Declaration

    Science.gov (United States)

    Beldavs, V.; Foing, B.; Bland, D.; Crisafulli, J.

    2015-10-01

    The International Lunar Decade Declaration was discussed at the conference held November 9-13, 2014 in Hawaii "The Next Giant Leap: Leveraging Lunar Assets for Sustainable Pathways to Space" - http://2014giantleap.aerospacehawaii.info/ and accepted by a core group that forms the International Lunar Decade Working Group (ILDWG) that is seeking to make the proposed global event and decade long process a reality. The Declaration will be updated from time to time by members of the ILDWreflecting new knowledge and fresh perspectives that bear on building a global consortium with a mission to progress from lunar exploration to the transformation of the Moon into a wealth gene rating platform for the expansion of humankind into the solar system. When key organizations have endorsed the idea and joined the effort the text of the Declaration will be considered final. An earlier International Lunar Decade proposal was issued at the 8th ICEUM Conference in 2006 in Beijing together with 13 specific initiatives for lunar exploration[1,2,3]. These initiatives have been largely implemented with coordination among the different space agencies involved provided by the International Lunar Exploration Working Group[2,3]. The Second International Lunar Decade from 2015 reflects current trends towards increasing involvement of commercial firms in space, particularly seeking opportunities beyond low Earth orbit. The central vision of the International Lunar Decade is to build the foundations for a sustainable space economy through international collaboration concurrently addressing Lunar exploration and building a shared knowledge base;Policy development that enables collabo rative research and development leading to lunar mining and industrial and commercial development;Infrastructure on the Moon and in cislunar space (communications, transport, energy systems, way-stations, other) that reduces costs, lowers risks and speeds up the time to profitable operations;Enabling technologies

  1. Isotopic Evidence for Multi-stage Cosmic-ray Exposure Histories of Lunar Meteorites: Long Residence on the Moon and Short Transition to the Earth

    International Nuclear Information System (INIS)

    Hidaka, Hiroshi; Sakuma, Keisuke; Nishiizumi, Kunihiko; Yoneda, Shigekazu

    2017-01-01

    It is known that most lunar meteorites have complicated cosmic-ray exposure experiences on the Moon and in space. In this study, cosmic-ray irradiation histories of six lunar meteorites, Dhofar 489, Northwest Africa 032 (NWA 032), NWA 479, NWA 482, NWA 2995, and NWA 5000, were characterized from neutron-captured isotopic shifts of Sm and Gd, and from the abundances of long-lived cosmogenic radionuclides like 10 Be, 26 Al, 36 Cl, and 41 Ca. Sm and Gd isotopic data of all of six meteorites show significant isotopic shifts of 149 Sm– 150 Sm and 157 Gd– 158 Gd caused by accumulation of neutron capture reactions due to cosmic-ray irradiation, corresponding to the neutron fluences of (1.3–9.6) × 10 16 n cm −2 . In particular, very large Sm and Gd isotopic shifts of NWA 482 are over those of a lunar regolith 70002, having the largest isotopic shifts among the Apollo regolith samples, corresponding to cosmic-ray exposure duration over 800 million years in the lunar surface (2 π irradiation). Meanwhile, the concentrations of cosmogenic radionuclides for individual six meteorites show the short irradiation time less than one million years as their bodies in space (4 π irradiation). Our data also support the results of previous studies, revealing that most of lunar meteorites have long exposure ages at shallow depths on the Moon and short transit times from the Moon to the Earth.

  2. High-Fidelity Gas and Granular Flow Physics Models for Rocket Exhaust Interaction with Lunar Soil, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Soil debris liberated by spacecraft landing on the lunar surface may damage and contaminate surrounding spacecraft and habitat structures. Current numerical...

  3. Ilmenite-rich pyroclastic deposits - An ideal lunar resource

    Science.gov (United States)

    Hawke, B. R.; Clark, B.; Coombs, C. R.

    1990-01-01

    With a view of investigating possible economic benefits that a permanent lunar settlement might provide to the near-earth space infrastructures, consideration was given to the ilmenite-rich pyroclastic deposits as sources of oxygen (for use as a propellant) and He-3 (for nuclear fusion fuel). This paper demonstrates that ilmenite-rich pyroclastic deposits would be excellent sources of a wide variety of valuable elements besides O and He-3, including Fe, Ti, H2, N, C, S, Cu, Zn, Cd, Bi, and Pb. It is shown that several ilmenite-rich pyroclastic deposits of regional extent exist on the lunar surface. The suitability of regional pyroclastic deposits for lunar mining operations, construction activities, and the establishment of permanent lunar settlements is examined.

  4. CE-4 Mission and Future Journey to Lunar

    Science.gov (United States)

    Zou, Yongliao; Wang, Qin; Liu, Xiaoqun

    2016-07-01

    Chang'E-4 mission, being undertaken by phase two of China Lunar Exploration Program, represents China's first attempt to explore farside of lunar surface. Its probe includes a lander, a rover and a telecommunication relay which is scheduled to launch in around 2018. The scientific objectives of CE-4 mission will be implemented to investigate the lunar regional geological characteristics of landing and roving area, and also will make the first radio-astronomy measurements from the most radio-quiet region of near-earth space. The rover will opreate for at least 3 months, the lander for half a year, and the relay for no less than 3 years. Its scinetific instruments includes Cameras, infrared imaging spectrometer, Penetrating Radar onboard the rover in which is the same as the paylads on board the CE-3 rover, and a Dust-analyzer, a Temperature-instrument and a Wide Band Low Frequency Digital Radio Astronomical Station will be installed on board the lander. Our scientific goals of the future lunar exploration will aim at the lunar geology, resources and surface environments. A series of exploraion missions such as robotic exploration and non-manned lunar scientific station is proposed in this paper.

  5. Elemental Mercury Diffusion Processes and Concentration at the Lunar Poles

    Science.gov (United States)

    Moxley, Frederick; Killen, Rosemary M.; Hurley, Dana M.

    2011-01-01

    In 2009, the Lyman Alpha Mapping Project (LAMP) spectrograph onboard the Lunar Reconnaissance Orbiter (LRO) spacecraft made the first detection of element mercury (Hg) vapor in the lunar exosphere after the Lunar Crater Observing and Sensing Satellite (LCROSS) Centaur rocket impacted into the Cabeus crater in the southern polar region of the Moon. The lunar regolith core samples from the Apollo missions determined that Hg had a devolatilized pattern with a concentration gradient increasing with depth, in addition to a layered pattern suggesting multiple episodes of burial and volatile loss. Hg migration on the lunar surface resulted in cold trapping at the poles. We have modeled the rate at which indigenous Hg is lost from the regolith through diffusion out of lunar grains. We secondly modeled the migration of Hg vapor in the exosphere and estimated the rate of cold-trapping at the poles using a Monte Carlo technique. The Hg vapor may be lost from the exosphere via ionization, Jeans escape, or re-impact into the surface causing reabsorption.

  6. Lagrangian Trajectory Modeling of Lunar Dust Particles

    Science.gov (United States)

    Lane, John E.; Metzger, Philip T.; Immer, Christopher D.

    2008-01-01

    Apollo landing videos shot from inside the right LEM window, provide a quantitative measure of the characteristics and dynamics of the ejecta spray of lunar regolith particles beneath the Lander during the final 10 [m] or so of descent. Photogrammetry analysis gives an estimate of the thickness of the dust layer and angle of trajectory. In addition, Apollo landing video analysis divulges valuable information on the regolith ejecta interactions with lunar surface topography. For example, dense dust streaks are seen to originate at the outer rims of craters within a critical radius of the Lander during descent. The primary intent of this work was to develop a mathematical model and software implementation for the trajectory simulation of lunar dust particles acted on by gas jets originating from the nozzle of a lunar Lander, where the particle sizes typically range from 10 micron to 500 micron. The high temperature, supersonic jet of gas that is exhausted from a rocket engine can propel dust, soil, gravel, as well as small rocks to high velocities. The lunar vacuum allows ejected particles to travel great distances unimpeded, and in the case of smaller particles, escape velocities may be reached. The particle size distributions and kinetic energies of ejected particles can lead to damage to the landing spacecraft or to other hardware that has previously been deployed in the vicinity. Thus the primary motivation behind this work is to seek a better understanding for the purpose of modeling and predicting the behavior of regolith dust particle trajectories during powered rocket descent and ascent.

  7. Liquid Methane Conditioning Capabilities Developed at the NASA Glenn Research Center's Small Multi- Purpose Research Facility (SMiRF) for Accelerated Lunar Surface Storage Thermal Testing

    Science.gov (United States)

    Bamberger, Helmut H.; Robinson, R. Craig; Jurns, John M.; Grasl, Steven J.

    2011-01-01

    Glenn Research Center s Creek Road Cryogenic Complex, Small Multi-Purpose Research Facility (SMiRF) recently completed validation / checkout testing of a new liquid methane delivery system and liquid methane (LCH4) conditioning system. Facility checkout validation was conducted in preparation for a series of passive thermal control technology tests planned at SMiRF in FY10 using a flight-like propellant tank at simulated thermal environments from 140 to 350K. These tests will validate models and provide high quality data to support consideration of LCH4/LO2 propellant combination option for a lunar or planetary ascent stage.An infrastructure has been put in place which will support testing of large amounts of liquid methane at SMiRF. Extensive modifications were made to the test facility s existing liquid hydrogen system for compatibility with liquid methane. Also, a new liquid methane fluid conditioning system will enable liquid methane to be quickly densified (sub-cooled below normal boiling point) and to be quickly reheated to saturation conditions between 92 and 140 K. Fluid temperatures can be quickly adjusted to compress the overall test duration. A detailed trade study was conducted to determine an appropriate technique to liquid conditioning with regard to the SMiRF facility s existing infrastructure. In addition, a completely new roadable dewar has been procured for transportation and temporary storage of liquid methane. A new spherical, flight-representative tank has also been fabricated for integration into the vacuum chamber at SMiRF. The addition of this system to SMiRF marks the first time a large-scale liquid methane propellant test capability has been realized at Glenn.This work supports the Cryogenic Fluid Management Project being conducted under the auspices of the Exploration Technology Development Program, providing focused cryogenic fluid management technology efforts to support NASA s future robotic or human exploration missions.

  8. Sources of Sodium in the Lunar Exosphere: Modeling Using Ground-Based Observations of Sodium Emission and Spacecraft Data of the Plasma

    Science.gov (United States)

    Sarantos, Menelaos; Killen, Rosemary M.; Sharma, A. Surjalal; Slavin, James A.

    2009-01-01

    Observations of the equatorial lunar sodium emission are examined to quantify the effect of precipitating ions on source rates for the Moon's exospheric volatile species. Using a model of exospheric sodium transport under lunar gravity forces, the measured emission intensity is normalized to a constant lunar phase angle to minimize the effect of different viewing geometries. Daily averages of the solar Lyman alpha flux and ion flux are used as the input variables for photon-stimulated desorption (PSD) and ion sputtering, respectively, while impact vaporization due to the micrometeoritic influx is assumed constant. Additionally, a proxy term proportional to both the Lyman alpha and to the ion flux is introduced to assess the importance of ion-enhanced diffusion and/or chemical sputtering. The combination of particle transport and constrained regression models demonstrates that, assuming sputtering yields that are typical of protons incident on lunar soils, the primary effect of ion impact on the surface of the Moon is not direct sputtering but rather an enhancement of the PSD efficiency. It is inferred that the ion-induced effects must double the PSD efficiency for flux typical of the solar wind at 1 AU. The enhancement in relative efficiency of PSD due to the bombardment of the lunar surface by the plasma sheet ions during passages through the Earth's magnetotail is shown to be approximately two times higher than when it is due to solar wind ions. This leads to the conclusion that the priming of the surface is more efficiently carried out by the energetic plasma sheet ions.

  9. MHD Convective Flow of Jeffrey Fluid Due to a Curved Stretching Surface with Homogeneous-Heterogeneous Reactions.

    Directory of Open Access Journals (Sweden)

    Maria Imtiaz

    Full Text Available This paper looks at the flow of Jeffrey fluid due to a curved stretching sheet. Effect of homogeneous-heterogeneous reactions is considered. An electrically conducting fluid in the presence of applied magnetic field is considered. Convective boundary conditions model the heat transfer analysis. Transformation method reduces the governing nonlinear partial differential equations into the ordinary differential equations. Convergence of the obtained series solutions is explicitly discussed. Characteristics of sundry parameters on the velocity, temperature and concentration profiles are analyzed by plotting graphs. Computations for pressure, skin friction coefficient and surface heat transfer rate are presented and examined. It is noted that fluid velocity and temperature through curvature parameter are enhanced. Increasing values of Biot number correspond to the enhancement in temperature and Nusselt number.

  10. Cooling Rates of Lunar Volcanic Glass Beads

    Science.gov (United States)

    Hui, Hejiu; Hess, Kai-Uwe; Zhang, Youxue; Peslier, Anne; Lange, Rebecca; Dingwell, Donald; Neal, Clive

    2016-01-01

    It is widely accepted that the Apollo 15 green and Apollo 17 orange glass beads are of volcanic origin. The diffusion profiles of volatiles in these glass beads are believed to be due to degassing during eruption (Saal et al., 2008). The degree of degassing depends on the initial temperature and cooling rate. Therefore, the estimations of volatiles in parental magmas of lunar pyroclastic deposits depend on melt cooling rates. Furthermore, lunar glass beads may have cooled in volcanic environments on the moon. Therefore, the cooling rates may be used to assess the atmospheric condition in an early moon, when volcanic activities were common. The cooling rates of glasses can be inferred from direct heat capacity measurements on the glasses themselves (Wilding et al., 1995, 1996a,b). This method does not require knowledge of glass cooling environments and has been applied to calculate the cooling rates of natural silicate glasses formed in different terrestrial environments. We have carried out heat capacity measurements on hand-picked lunar glass beads using a Netzsch DSC 404C Pegasus differential scanning calorimeter at University of Munich. Our preliminary results suggest that the cooling rate of Apollo 17 orange glass beads may be 12 K/min, based on the correlation between temperature of the heat capacity curve peak in the glass transition range and glass cooling rate. The results imply that the parental magmas of lunar pyroclastic deposits may have contained more water initially than the early estimations (Saal et al., 2008), which used higher cooling rates, 60-180 K/min in the modeling. Furthermore, lunar volcanic glass beads could have been cooled in a hot gaseous medium released from volcanic eruptions, not during free flight. Therefore, our results may shed light on atmospheric condition in an early moon.

  11. Scientific Objectives of China Chang E 4 CE-4 Lunar Far-side Exploration Mission

    Science.gov (United States)

    Zhang, Hongbo; Zeng, Xingguo; Chen, Wangli

    2017-10-01

    China has achieved great success in the recently CE-1~CE-3 lunar missions, and in the year of 2018, China Lunar Exploration Program (CLEP) is going to launch the CE-4 mission. CE-4 satellite is the backup satellite of CE-3, so that it also consists of a Lander and a Rover. However, CE-4 is the first mission designed to detect the far side of the Moon in human lunar exploration history. So the biggest difference between CE-4 and CE-3 is that it will be equipped with a relay satellite in Earth-Moon-L2 Point for Earth-Moon Communication. And the scientific payloads carried on the Lander and Rover will also be different. It has been announced by the Chinese government that CE-4 mission will be equipped with some new international cooperated scientific payloads, such as the Low Frequency Radio Detector from Holland, Lunar Neutron and Radiation Dose Detector from Germany, Neutral Atom Detector from Sweden, and Lunar Miniature Optical Imaging Sounder from Saudi Arabia. The main scientific objective of CE-4 is to provide scientific data for lunar far side research, including: 1)general spatial environmental study of lunar far side;2)general research on the surface, shallow layer and deep layer of lunar far side;3)detection of low frequency radio on lunar far side using Low Frequency Radio Detector, which would be the first time of using such frequency band in lunar exploration history .

  12. Lunar Airborne Dust Toxicity Hazard Assessments (Invited)

    Science.gov (United States)

    Cooper, B. L.; McKay, D. S.; Taylor, L. A.; Wallace, W. T.; James, J.; Riofrio, L.; Gonzalez, C. P.

    2009-12-01

    The Lunar Airborne Dust Toxicity Assessment Group (LADTAG) is developing data to set the permissible limits for human exposure to lunar dust. This standard will guide the design of airlocks and ports for EVA, as well as the requirements for filtering and monitoring the atmosphere in habitable vehicles, rovers and other modules. LADTAG’s recommendation for permissible exposure limits will be delivered to the Constellation Program in late 2010. The current worst-case exposure limit of 0.05 mg/m3, estimated by LADTAG in 2006, reflects the concern that lunar dust may be as toxic as quartz dust. Freshly-ground quartz is known to be more toxic than un-ground quartz dust. Our research has shown that the surfaces of lunar soil grains can be more readily activated by grinding than quartz. Activation was measured by the amount of free radicals generated—activated simulants generate Reactive Oxygen Species (ROS) i.e., production of hydroxyl free radicals. Of the various influences in the lunar environment, micrometeorite bombardment probably creates the most long-lasting reactivity on the surfaces of grains, although solar wind impingement and short-wavelength UV radiation also contribute. The comminution process creates fractured surfaces with unsatisfied bonds. When these grains are inhaled and carried into the lungs, they will react with lung surfactant and cells, potentially causing tissue damage and disease. Tests on lunar simulants have shown that dissolution and leaching of metals can occur when the grains are exposed to water—the primary component of lung fluid. However, simulants may behave differently than actual lunar soils. Rodent toxicity testing will be done using the respirable fraction of actual lunar soils (particles with physical size of less than 2.5 micrometers). We are currently separating the fine material from the coarser material that comprises >95% of the mass of each soil sample. Dry sieving is not practical in this size range, so a new system

  13. ''Fast track'' lunar NTR systems assessment for NASA's first lunar outpost and its evolvability to Mars

    International Nuclear Information System (INIS)

    Borowski, S.K.; Alexander, S.W.

    1993-01-01

    Integrated systems and missions studies are presented for an evolutionary lunar-to-Mars space transportion system (STS) based on nuclear thermal rocket (NTR) technology. A ''standardized'' set of engine and stage components are identified and used in a ''building block'' fashion to configure a variety of piloted and cargo, lunar and Mars vehicles. The reference NTR characteristics include a thrust of 50 thousand pounds force (klbf), specific impulse (I sp ) of 900 seconds, and an engine thrust-to-weight ratio of 4.3. For the National Aeronautics and Space Administration's (NASA) First Lunar Outpost (FLO) mission, an expendable NTR stage powered by two such engines can deliver ∼96 metric tonnes (t) to trans-lunar injection (TLI) conditions for an initial mass in low Earth orbit (IMLEO) of ∼198 t compared to 250 t for a cryogenic chemical system. The stage liquid hydrogen (LH 2 ) tank has a diameter, length, and capacity of 10 m, 14.5 m and 66 t, respectively. By extending the stage length and LH 2 capacity to ∼20 m and 96 t, a single launch Mars cargo vehicle could deliver to an elliptical Mars parking orbit a 63 t Mars excursion vehicle (MEV) with a 45 t surface payload. Three 50 klbf engines and the two standardized LH 2 tanks developed for the lunar and Mars cargo vehicles are used to configure the vehicles supporting piloted Mars missions as early as 2010. The ''modular'' NTR vehicle approach forms the basis for an efficient STS able to handle the needs of a wide spectrum of lunar and Mars missions

  14. Theoretical aspects of the electronical devices operating due to interaction between annular electron beams and the azimuthal surface waves

    Energy Technology Data Exchange (ETDEWEB)

    Girka, V O; Girka, I O [Kharkiv State Univ. (Ukraine)

    1997-12-31

    The physical basis is discussed of electronic devices whose operation is based on the beam or dissipative instability of the azimuthal surface waves (ASW). The ASW are electromagnetic surface waves with extraordinary polarization (with field components E{sub r}, E{sub {phi}}, H{sub z}), propagating across the axial external steady magnetic field in the cylindrical metal waveguide with cold plasma filling. The ASW fields are described by Maxwell equations. To solve the problem, the authors used the Fourier method and numerical simulation of the equations obtained. The ASW excitation was examined under conditions of beam and dissipative instabilities due to the electron beam motion. The correction to ASW eigenfrequencies caused by the waveguide chamber noncircularity was also studied. ASW delaying leads to a negative frequency correction. The ASW energy can be emitted from the narrow slot in the metallic chamber of the waveguide. The optimum wavenumber range was found where the increment values are much greater than those of the ASW decrement caused by their energy radiation. (author). 2 figs., 3 refs.

  15. Film Thickness Formation in Nanoscale due to Effects of Elastohydrodynamic, Electrostatic and Surface force of Solvation and Van der Waals

    Directory of Open Access Journals (Sweden)

    M.F. Abd Al-Samieh

    2017-03-01

    Full Text Available The mechanism of oil film with a thickness in the nanoscale is discussed in this paper. A polar lubricant of propylene carbonate is used as the intervening liquid between contiguous bodies in concentrated contacts. A pressure caused by the hydrodynamic viscous action in addition to double layer electrostatic force, Van der Waals inter-molecular forces, and solvation pressure due to inter-surface forces is considered in calculating the ultrathin lubricating films. The numerical solution has been carried out, using the Newton-Raphson iteration technique, applied for the convergence of the hydrodynamic pressure. The results show that, at separations beyond about five molecular diameters of the intervening liquid, the formation of a lubricant film thickness is governed by combined effects of viscous action and surface force of an attractive Van der Waals force and a repulsive double layer force. At smaller separations below about five molecular diameters of the intervening liquid, the effect of solvation force is dominant in determining the oil film thickness

  16. Spectral Dependent Degradation of the Solar Diffuser on Suomi-NPP VIIRS Due to Surface Roughness-Induced Rayleigh Scattering

    Directory of Open Access Journals (Sweden)

    Xi Shao

    2016-03-01

    Full Text Available The Visible Infrared Imaging Radiometer Suite (VIIRS onboard Suomi National Polar Orbiting Partnership (SNPP uses a solar diffuser (SD as its radiometric calibrator for the reflective solar band calibration. The SD is made of Spectralon™ (one type of fluoropolymer and was chosen because of its controlled reflectance in the Visible/Near-Infrared/Shortwave-Infrared region and its near-Lambertian reflectance property. On-orbit changes in VIIRS SD reflectance as monitored by the Solar Diffuser Stability Monitor showed faster degradation of SD reflectance for 0.4 to 0.6 µm channels than the longer wavelength channels. Analysis of VIIRS SD reflectance data show that the spectral dependent degradation of SD reflectance in short wavelength can be explained with a SD Surface Roughness (length scale << wavelength based Rayleigh Scattering (SRRS model due to exposure to solar UV radiation and energetic particles. The characteristic length parameter of the SD surface roughness is derived from the long term reflectance data of the VIIRS SD and it changes at approximately the tens of nanometers level over the operational period of VIIRS. This estimated roughness length scale is consistent with the experimental result from radiation exposure of a fluoropolymer sample and validates the applicability of the Rayleigh scattering-based model. The model is also applicable to explaining the spectral dependent degradation of the SDs on other satellites. This novel approach allows us to better understand the physical processes of the SD degradation, and is complementary to previous mathematics based models.

  17. Reduction of transient diffusion from 1 endash 5 keV Si+ ion implantation due to surface annihilation of interstitials

    International Nuclear Information System (INIS)

    Agarwal, A.; Gossmann, H.-.; Eaglesham, D.J.; Pelaz, L.; Jacobson, D.C.; Haynes, T.E.; Erokhin, Y.E.

    1997-01-01

    The reduction of transient enhanced diffusion (TED) with reduced implantation energy has been investigated and quantified. A fixed dose of 1x10 14 cm -2 Si + was implanted at energies ranging from 0.5 to 20 keV into boron doping superlattices and enhanced diffusion of the buried boron marker layers was measured for anneals at 810, 950, and 1050 degree C. A linearly decreasing dependence of diffusivity enhancement on decreasing Si + ion range is observed at all temperatures, extrapolating to ∼1 for 0 keV. This is consistent with our expectation that at zero implantation energy there would be no excess interstitials from the implantation and hence no TED. Monte Carlo modeling and continuum simulations are used to fit the experimental data. The results are consistent with a surface recombination length for interstitials of <10 nm. The data presented here demonstrate that in the range of annealing temperatures of interest for p-n junction formation, TED is reduced at smaller ion implantation energies and that this is due to increased interstitial annihilation at the surface. copyright 1997 American Institute of Physics

  18. Numerical Simulations of the Lunar Penetrating Radar and Investigations of the Geological Structures of the Lunar Regolith Layer at the Chang’E 3 Landing Site

    Directory of Open Access Journals (Sweden)

    Chunyu Ding

    2017-01-01

    Full Text Available In the process of lunar exploration, and specifically when studying lunar surface structure and thickness, the established lunar regolith model is usually a uniform and ideal structural model, which is not well-suited to describe the real structure of the lunar regolith layer. The present study aims to explain the geological structural information contained in the channel 2 LPR (lunar penetrating radar data. In this paper, the random medium theory and Apollo drilling core data are used to construct a modeling method based on discrete heterogeneous random media, and the simulation data are processed and collected by the electromagnetic numerical method FDTD (finite-difference time domain. When comparing the LPR data with the simulated data, the heterogeneous random medium model is more consistent with the actual distribution of the media in the lunar regolith layer. It is indicated that the interior structure of the lunar regolith layer at the landing site is not a pure lunar regolith medium but rather a regolith-rock mixture, with rocks of different sizes and shapes. Finally, several reasons are given to explain the formation of the geological structures of the lunar regolith layer at the Chang’E 3 landing site, as well as the possible geological stratification structure.

  19. MODELING THE ANOMALY OF SURFACE NUMBER DENSITIES OF GALAXIES ON THE GALACTIC EXTINCTION MAP DUE TO THEIR FIR EMISSION CONTAMINATION

    Energy Technology Data Exchange (ETDEWEB)

    Kashiwagi, Toshiya; Suto, Yasushi; Taruya, Atsushi; Yahata, Kazuhiro [Department of Physics, The University of Tokyo, Tokyo 113-0033 (Japan); Kayo, Issha [Department of Physics, Toho University, Funabashi, Chiba 274-8510 (Japan); Nishimichi, Takahiro, E-mail: kashiwagi@utap.phys.s.u-tokyo.ac.jp [Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8568 (Japan)

    2015-02-01

    The most widely used Galactic extinction map is constructed assuming that the observed far-infrared (FIR) fluxes come entirely from Galactic dust. According to the earlier suggestion by Yahata et al., we consider how FIR emission of galaxies affects the SFD map. We first compute the surface number density of Sloan Digital Sky Survey (SDSS) DR7 galaxies as a function of the r-band extinction, A {sub r,} {sub SFD}. We confirm that the surface densities of those galaxies positively correlate with A {sub r,} {sub SFD} for A {sub r,} {sub SFD} < 0.1, as first discovered by Yahata et al. for SDSS DR4 galaxies. Next we construct an analytical model to compute the surface density of galaxies, taking into account the contamination of their FIR emission. We adopt a log-normal probability distribution for the ratio of 100 μm and r-band luminosities of each galaxy, y ≡ (νL){sub 100} {sub μm}/(νL) {sub r}. Then we search for the mean and rms values of y that fit the observed anomaly, using the analytical model. The required values to reproduce the anomaly are roughly consistent with those measured from the stacking analysis of SDSS galaxies. Due to the limitation of our statistical modeling, we are not yet able to remove the FIR contamination of galaxies from the extinction map. Nevertheless, the agreement with the model prediction suggests that the FIR emission of galaxies is mainly responsible for the observed anomaly. Whereas the corresponding systematic error in the Galactic extinction map is 0.1-1 mmag, it is directly correlated with galaxy clustering and thus needs to be carefully examined in precision cosmology.

  20. Alteration of the Carbon and Nitrogen Isotopic Composition in the Martian Surface Rocks Due to Cosmic Ray Exposure

    Science.gov (United States)

    Pavlov, A. A.; Pavlov, A. K.; Ostryakov, V. M.; Vasilyev, G. I.; Mahaffy, P.; Steele, A.

    2014-01-01

    C-13/C-12 and N-15/N-14 isotopic ratios are pivotal for our understanding of the Martian carbon cycle, history of the Martian atmospheric escape, and origin of the organic compounds on Mars. Here we demonstrate that the carbon and nitrogen isotopic composition of the surface rocks on Mars can be significantly altered by the continuous exposure of Martian surface to cosmic rays. Cosmic rays can effectively produce C-13 and N-15 isotopes via spallation nuclear reactions on oxygen atoms in various Martian rocks. We calculate that in the top meter of the Martian rocks, the rates of production of both C-13 and N-15 due to galactic cosmic rays (GCRs) exposure can vary within 1.5-6 atoms/cm3/s depending on rocks' depth and chemical composition. We also find that the average solar cosmic rays can produce carbon and nitrogen isotopes at a rate comparable to GCRs in the top 5-10 cm of the Martian rocks. We demonstrate that if the total carbon content in a surface Martian rock is <10 ppm, then the "light," potentially "biological" C-13/C-12 ratio would be effectively erased by cosmic rays over 3.5 billion years of exposure. We found that for the rocks with relatively short exposure ages (e.g., 100 million years), cosmogenic changes in N-15/N-14 ratio are still very significant. We also show that a short exposure to cosmic rays of Allan Hills 84001 while on Mars can explain its high-temperature heavy nitrogen isotopic composition (N-15/N-14). Applications to Martian meteorites and the current Mars Science Laboratory mission are discussed.

  1. Differential loggerhead by-catch and direct mortality due to surface longlines according to boat strata and gear type

    Directory of Open Access Journals (Sweden)

    Juan A. Camiñas

    2006-12-01

    Full Text Available Surface longline gears are used to fish different species, mainly albacore Thunnus alalunga (Bonnaterre, 1788, bluefin tuna Thunnus thynnus (Linnaeus, 1758, and swordfish Xiphias gladius Linnaeus, 1758, and are considered highly dangerous for threatened marine turtles. Loggerheads Caretta caretta (Linnaeus, 1758 can be incidentally captured by surface longlines. A number of captured individuals die during the fishing operation, which we consider direct mortality due to fishing. We analysed the relative loggerhead by-catch and direct mortality associated with each type of boat and gear from April to December during the period 1999-2004 in the Spanish surface longline fleet that fishes in the western Mediterranean Sea, an important fishing area for this fleet. We used different indices to compute the catch per unit effort (CPUE according to the number of hooks and to the number of fishing operations for each type of boat and gear. Both by-catch and direct mortality differed significantly according to the type of boat and gear. With respect to the number of hooks, boats longer than 12 m not using a roller and targeting bluefin tuna captured the highest number of loggerheads, whereas boats longer than 12 m with a roller that targeted swordfish caused the highest direct mortality. With respect to the number of fishing operations, boats longer than 12 m without a roller that targeted albacore captured the highest number of loggerheads; the highest direct mortality was caused by this type of boat and by boats longer than 12 m using a roller and targeting swordfish.

  2. International Lunar Decade Status

    Science.gov (United States)

    Beldavs, VZ; Crisafulli, J.; Dunlop, D.; Foing, B.

    2017-09-01

    The International Lunar Decade is a global decadal event designed to provide a framework for strategically directed international cooperation for permanent return to the Moon. To be launched July 20, 2019, the 50th anniversary of the giant leap for mankind marked by Neil Armstrong's first step on the Moon, the ILD launch will include events around the world to celebrate space exploration, science, and the expansion of humanity into the Solar System. The ILD framework links lunar exploration and space sciences with the development of enabling technologies, infrastructure, means of financing, laws and policies aimed at lowering the costs and risks of venturing into space. Dramatically reduced costs will broaden the range of opportunities available in space and widen access to space for more states, companies and people worldwide. The ILD is intended to bring about the efflorescence of commercial business based on space resources from the Moon, asteroids, comets and other bodies in the Solar System.

  3. Lunar Health Monitor (LHM)

    Science.gov (United States)

    Lisy, Frederick J.

    2015-01-01

    Orbital Research, Inc., has developed a low-profile, wearable sensor suite for monitoring astronaut health in both intravehicular and extravehicular activities. The Lunar Health Monitor measures respiration, body temperature, electrocardiogram (EKG) heart rate, and other cardiac functions. Orbital Research's dry recording electrode is central to the innovation and can be incorporated into garments, eliminating the need for conductive pastes, adhesives, or gels. The patented dry recording electrode has been approved by the U.S. Food and Drug Administration. The LHM is easily worn under flight gear or with civilian clothing, making the system completely versatile for applications where continuous physiological monitoring is needed. During Phase II, Orbital Research developed a second-generation LHM that allows sensor customization for specific monitoring applications and anatomical constraints. Evaluations included graded exercise tests, lunar mission task simulations, functional battery tests, and resting measures. The LHM represents the successful integration of sensors into a wearable platform to capture long-duration and ambulatory physiological markers.

  4. The Lunar Sample Compendium

    Science.gov (United States)

    Meyer, Charles

    2009-01-01

    The Lunar Sample Compendium is a succinct summary of the data obtained from 40 years of study of Apollo and Luna samples of the Moon. Basic petrographic, chemical and age information is compiled, sample-by-sample, in the form of an advanced catalog in order to provide a basic description of each sample. The LSC can be found online using Google. The initial allocation of lunar samples was done sparingly, because it was realized that scientific techniques would improve over the years and new questions would be formulated. The LSC is important because it enables scientists to select samples within the context of the work that has already been done and facilitates better review of proposed allocations. It also provides back up material for public displays, captures information found only in abstracts, grey literature and curatorial databases and serves as a ready access to the now-vast scientific literature.

  5. Lunar concrete for construction

    Science.gov (United States)

    Cullingford, Hatice S.; Keller, M. Dean

    1988-01-01

    Feasibility of using concrete for lunar-base construction has been discussed recently without relevant data for the effects of vacuum on concrete. Experimental studies performed earlier at Los Alamos have shown that concrete is stable in vacuum with no deterioration of its quality as measured by the compressive strength. Various considerations of using concrete successfully on the moon are provided in this paper along with specific conclusions from the existing data base.

  6. First lunar outpost

    Science.gov (United States)

    Andino, Aureo F.; Silva, Daniel; Ortiz, Nelson; Alvarez, Omar; Colon, Julio A.; Colon, Myrelle; Diaz, Alicia; Escobar, Xochiquetzal Y.; Garcia, Alberto; Gonzalez, Isabel C.

    1992-01-01

    Design and research efforts at the University of Puerto Rico have focused on the evaluation and refinement of the Habitability Criteria for a prolonged human presence in space during the last four years. Living quarters for a Mars mission and a third generation lunar base concept were proposed. This academic year, 1991-92, work on further refinement of the habitability criteria and design of partial gravity furniture was carried on. During the first semester, design alternatives for furniture necessary in a habitat design optimized for lunar and Martian environments were developed. Designs are based on recent research data from lunar and Mars gravity simulations, and current NASA standards. Artifacts will be submitted to NASA architects to be tested in KC-135 flights. Test findings will be submitted for incorporation in future updates to NASA habitat design standards. Second semester work was aimed at integrating these findings into the First Lunar Outpost (FLO), a mission scenario currently being considered by NASA. The mission consists of a manned return to the moon by crews of four astronauts for periods of 45 days. The major hardware components of the mission are as follows: (1) a Crew Module for the delivery of the crew and their supplies, and (2) the Habitat Module, which will arrive on the Moon unmanned. Our design efforts concentrated on this Habitat Module and on application of habitability criteria. Different geometries for the pressure vessel and their impact on the interior architecture were studied. Upon the selection of a geometry, a more detailed analysis of the interior design was performed, taking into consideration the reduced gravity, and the protection against radiation, micrometeorites, and the extreme temperature variation. A proposal for a FLO was submitted by the students, consisting essentially of a 24-feet (7.3 m.) by 35-feet (10.67 m) high vertical cylinder with work areas, crew quarters, galley, wardroom, leisure facilities, health

  7. Religion and Lunar Exploration

    Science.gov (United States)

    Pop, V.

    1969: The Eagle lands on the Moon. A moment that would not only mark the highest scientific achievement of all times, but would also have significant religious impli- cations. While the island of Bali lodges a protest at the United Nations against the US for desecrating a sacred place, Hopi Indians celebrate the fulfilment of an ancient prophecy that would reveal the "truth of the Sacred Ways". The plaque fastened to the Eagle - "We Came in Peace for All Mankind" would have contained the words "under God" as directed by the US president, if not for an assistant administrator at NASA that did not want to offend any religion. In the same time, Buzz Aldrin takes the Holy Communion on the Moon, and a Bible is left there by another Apollo mission - not long after the crew of Apollo 8 reads a passage from Genesis while circling the Moon. 1998: Navajo Indians lodge a protest with NASA for placing human ashes aboard the Lunar Prospector, as the Moon is a sacred place in their religion. Past, present and fu- ture exploration of the Moon has significant religious and spiritual implications that, while not widely known, are nonetheless important. Is lunar exploration a divine duty, or a sacrilege? This article will feature and thoroughly analyse the examples quoted above, as well as other facts, as for instance the plans of establishing lunar cemeteries - welcomed by some religions, and opposed by others.

  8. Lunar sample studies

    International Nuclear Information System (INIS)

    1977-01-01

    Lunar samples discussed and the nature of their analyses are: (1) an Apollo 15 breccia which is thoroughly analyzed as to the nature of the mature regolith from which it derived and the time and nature of the lithification process, (2) two Apollo 11 and one Apollo 12 basalts analyzed in terms of chemistry, Cross-Iddings-Pirsson-Washington norms, mineralogy, and petrography, (3) eight Apollo 17 mare basalts, also analyzed in terms of chemistry, Cross-Iddings-Pirsson-Washington norms, mineralogy, and petrography. The first seven are shown to be chemically similar although of two main textural groups; the eighth is seen to be distinct in both chemistry and mineralogy, (4) a troctolitic clast from a Fra Mauro breccia, analyzed and contrasted with other high-temperature lunar mineral assemblages. Two basaltic clasts from the same breccia are shown to have affinities with rock 14053, and (5) the uranium-thorium-lead systematics of three Apollo 16 samples are determined; serious terrestrial-lead contamination of the first two samples is attributed to bandsaw cutting in the lunar curatorial facility

  9. Modeling lunar volcanic eruptions

    Science.gov (United States)

    Housley, R. M.

    1978-01-01

    Simple physical arguments are used to show that basaltic volcanos on different planetary bodies would fountain to the same height if the mole fraction of gas in the magma scaled with the acceleration of gravity. It is suggested that the actual eruption velocities and fountain heights are controlled by the velocities of sound in the two phase gas/liquid flows. These velocities are in turn determined by the gas contents in the magma. Predicted characteristics of Hawaiian volcanos are in excellent accord with observations. Assuming that the only gas in lunar volcano is the CO which would be produced if the observed Fe metal in lunar basalts resulted from graphite reduction, lunar volcanos would fountain vigorously, but not as spectacularly as their terrestrial counterparts. The volatile trace metals, halogens, and sulfur released would be transported over the entire moon by the transient atmosphere. Orange and black glass type pyroclastic materials would be transported in sufficient amounts to produce the observed dark mantle deposits.

  10. Lunar lander stage requirements based on the Civil Needs Data Base

    Science.gov (United States)

    Mulqueen, John A.

    1992-01-01

    This paper examines the lunar lander stages that will be necessary for the future exploration and development of the Moon. Lunar lander stage sizing is discussed based on the projected lunar payloads listed in the Civil Needs Data Base. Factors that will influence the lander stage design are identified and discussed. Some of these factors are (1) lunar orbiting and lunar surface lander bases; (2) implications of direct landing trajectories and landing from a parking orbit; (3) implications of landing site and parking orbit; (4) implications of landing site and parking orbit selection; (5) the use of expendable and reusable lander stages; and (6) the descent/ascent trajectories. Data relating the lunar lander stage design requirements to each of the above factors and others are presented in parametric form. These data will provide useful design data that will be applicable to future mission model modifications and design studies.

  11. The Lunar Environment: Determining the Health Effects of Exposure to Moon Dusts

    Science.gov (United States)

    Khan-Mayberry, Noreen

    2007-01-01

    The moon's surface is covered with a thin layer of fine, charged, reactive dust capable of layer of fine, charged, reactive dust capable of capable of entering habitats and vehicle compartments, where it can result in crewmember health problems. NASA formed the Lunar Airborne Dust Toxicity Advisory Group (LADTAG) to study the effects of exposure to Lunar Dust on human health. To date, no scientifically defensible toxicological studies have been performed on lunar dusts, specifically the determination of exposure limits and their affect on human health. The multi-center LADTAG (Lunar Airborne Dust Toxicology center LADTAG (Lunar Airborne Dust Toxicology Advisory Group) was formed in response to the Office of the Chief Health and Medical Office s (OCHMO) request to develop recommendations for defining risk (OCHMO) request to develop recommendations for defining risk defining risk criteria for human lunar dust exposure.

  12. First Results from NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE)

    Science.gov (United States)

    Elphic, R. C.; Colaprete, A.; Horanyi, M.; Mahaffy, P. R.; Delory, G. T.; Noble, S. K.; Boroson, D.; Hine, B.; Salute, J.

    2013-12-01

    As of early August, 2013, the Lunar Atmosphere and Dust Environment Explorer (LADEE) mission is scheduled for launch on a Minotaur V rocket from Wallops Flight Facility during a five-day launch period that opens on Sept. 6, 2013 (early Sept. 7 UTC). LADEE will address 40 year-old mysteries of the lunar atmosphere and the question of levitated lunar dust. It will also pioneer the next generation of optical space communications. LADEE will assess the composition of the lunar atmosphere and investigate the processes that control its distribution and variability, including sources, sinks, and surface interactions. LADEE will also determine whether dust is present in the lunar exosphere, and reveal its sources and variability. These investigations are relevant to our understanding of surface boundary exospheres and dust processes occurring at many objects throughout the solar system, address questions regarding the origin and evolution of lunar volatiles, and have potential implications for future exploration activities. Following a successful launch, LADEE will enter a series of phasing orbits, which allows the spacecraft to arrive at the Moon at the proper time and phase. This approach accommodates any dispersion in the Minotaur V launch injection. LADEE's arrival at the moon depends on the launch date, but with the Sept. 6 launch date it should arrive at the Moon in early October. The spacecraft will approach the moon from its leading edge, travel behind the Moon out of sight of the Earth, and then re-emerge and execute a three-minute Lunar Orbit Insertion maneuver. This will place LADEE in an elliptical retrograde equatorial orbit with an orbital period of approximately 24 hours. A series of maneuvers is then performed to reduce the orbit to become nearly circular with a 156-mile (250-kilometer) altitude. Spacecraft checkout and science instrument commissioning will commence in early-October and will nominally span 30 days but can be extended for an additional 30

  13. Free surface flow under gravity and surface tension due to an applied pressure distribution: i Bond number greater than one-third

    Energy Technology Data Exchange (ETDEWEB)

    Maleewong, Montri; Asavanant, Jack [Chulalongkorn University, Department of Mathematics and Advanced Virtual Intelligence Computing Center, Bangkok (Thailand); Grimshaw, Roger [Loughborough University, Department of Mathematical Sciences, Loughborough (United Kingdom)

    2005-08-01

    We consider steady free surface two-dimensional flow due to a localized applied pressure distribution under the effects of both gravity and surface tension in water of constant depth, and in the presence of a uniform stream. The fluid is assumed to be inviscid and incompressible, and the flow is irrotational. The behavior of the forced nonlinear waves is characterized by three parameters: the Froude number, F, the Bond number, {tau}>1/3, and the magnitude and sign of the pressure forcing parameter {epsilon}. The fully nonlinear wave problem is solved numerically by using a boundary integral method. For small amplitude waves and F<1 but not too close to 1, linear theory gives a good prediction for the numerical solution of the nonlinear problem in the case of bifurcation from the uniform flow. As F approaches 1, the nonlinear terms need to be taken account of. In this case the forced Korteweg-de Vries equation is found to be an appropriate model to describe bifurcations from an unforced solitary wave. In general, it is found that for given values of F<1 and {tau}>1/3, there exists both elevation and depression waves. In some cases, a limiting configuration in the form of a trapped bubble occurs in the depression wave solutions. (orig.)

  14. Sources and physical processes responsible for OH/H2O in the lunar soil as revealed by the Moon Mineralogy Mapper (M3)

    Science.gov (United States)

    McCord, T.B.; Taylor, L.A.; Combe, J.-P.; Kramer, G.; Pieters, C.M.; Sunshine, J.M.; Clark, R.N.

    2011-01-01

    Analysis of two absorption features near 3 m in the lunar reflectance spectrum, observed by the orbiting M3 spectrometer and interpreted as being due to OH and H2O, is presented, and the results are used to discuss the processes producing these molecules. This analysis focuses on the dependence of the absorptions on lunar physical properties, including composition, illumination, latitude, and temperature. Solar wind proton-induced hydroxylation is proposed as the creation process, and its products could be a source for other reported types of hydrogen-rich material and water. The irregular and damaged fine-grained lunar soil seems especially adapted for trapping solar wind protons and forming OH owing to abundant dangling oxygen bonds. The M3 data reveal that the strengths of the two absorptions are correlated and widespread, and both are correlated with lunar composition but in different ways. Feldspathic material seems richer in OH. These results seem to rule out water from the lunar interior and cometary infall as major sources. There appear to be correlations of apparent band strengths with time of day and lighting conditions. However, thermal emission from the Moon reduces the apparent strengths of the M3 absorptions, and its removal is not yet completely successful. Further, many of the lunar physical properties are themselves intercorrelated, and so separating these dependencies on the absorptions is difficult, due to the incomplete M3 data set. This process should also operate on other airless silicate surfaces, such as Mercury and Vesta, which will be visited by the Dawn spacecraft in mid-2011. Copyright 2011 by the American Geophysical Union.

  15. Lunar construction/mining equipment

    Science.gov (United States)

    Ozdemir, Levent

    1990-01-01

    For centuries, mining has utilized drill and blast as the primary method of rock excavation. Although this technique has undergone significant improvements, it still remains a cyclic, labor intensive operation with inherent safety hazards. Other drawbacks include damage to the surrounding ground, creation of blast vibrations, rough excavation walls resulting in increased ventilation requirements, and the lack of selective mining ability. Perhaps the most important shortcoming of drill and blast is that it is not conducive to full implementation of automation or robotics technologies. Numerous attempts have been made in the past to automate drill and blast operations to remove personnel from the hazardous work environment. Although most of the concepts devised look promising on paper, none of them was found workable on a sustained production basis. In particular, the problem of serious damage to equipment during the blasting cycle could not be resolved regardless of the amount of charge used in excavation. Since drill and blast is not capable of meeting the requirements of a fully automated rock fragmentation method, its role is bound to gradually decrease. Mechanical excavation, in contrast, is highly suitable to automation because it is a continuous process and does not involve any explosives. Many of the basic principles and trends controlling the design of an earth-based mechanical excavator will hold in an extraterrestrial environment such as on the lunar surface. However, the economic and physical limitations for transporting materials to space will require major rethinking of these machines. In concept, then, a lunar mechanical excavator will look and perform significantly different from one designed for use here on earth. This viewgraph presentation gives an overview of such mechanical excavator systems.

  16. Interior design of the lunar outpost

    Science.gov (United States)

    Kennedy, Kriss J.

    1990-01-01

    This paper is part of an ongoing study on the interior design of a lunar outpost habitat facility. The concept presented represents the work done up to and including August 1989. This concept is part of NASA's ongoing effort to explore alternative options for planet surface systems habitation. Results of a volume analog study to determine the required pressurized volume are presented along with an internal layout of the habitat facility. The concept presented in this paper is a constructible lunar habitat that provides a living and working environment for a crew of 12. It is a 16-m diameter spherical pneumatic structure which contains 2145 cubic meters of volume. Five levels of living and working areas make up the 742 sq m of floor space. A 2-m vertical circulation shaft at the center allows for transfer of crew and equipment.

  17. Remanent magnetization stratigraphy of lunar cores

    Science.gov (United States)

    Banerjee, S. K.; Gingrich, D.; Marvin, J. A.

    1977-01-01

    Depth dependent fluctuations have been observed in the natural remanent magnetizations (NRM) of drive cores and drill strings from Apollo 16 and 17 missions. Partial demagnetization of unstable secondary magnetizations and identification of characteristic error signals from a core which is known to have been recently disturbed allow us to identify and isolate the stable NRM stratigraphy in double drive core 60010/60009 and drill strings 60002-60004. The observed magnetization fluctuations persist after normalization to take into account depth dependent variations in the carriers of stable NRM. We tentatively ascribe the stable NRM stratigraphy to instantaneous records of past magnetic fields at the lunar surface and suggest that the stable NRM stratigraphy technique could develop as a new relative time-stratigraphic tool, to be used with other physical measurements such as relative intensity of ferromagnetic resonance and charged particle track density to study the evolution of the lunar regolith.

  18. Lunar and solar daily variations of ionospheric electron content at Delhi

    International Nuclear Information System (INIS)

    Bhuyan, P.K.; Tyagi, T.R.

    1986-01-01

    Ionospheric electron content measurements obtained at Delhi during the period 1975-1980 have been analysed by the Chapman-Miller method to compute lunar and solar daily variations. The results show that the magnitude of the lunar harmonic components is about one-tenth that of the solar harmonic components. Significant seasonal and solar cycle variations were observed for both the lunar and the solar terms. The lunar semi-diurnal component, the most significant term, can be explained as due to the additional 'fountain' effect caused by the lunar semi-diurnal variation of the electric field at the equatorial region. The lunar semi-diurnal variations were found to have significant oceanic and ionospheric components. (author)

  19. Chlorine isotopic compositions of apatite in Apollo 14 rocks: Evidence for widespread vapor-phase metasomatism on the lunar nearside ∼4 billion years ago

    NARCIS (Netherlands)

    Potts, Nicola J.; Barnes, Jessica J.; Tartèse, Romain; Franchi, Ian A.; Anand, Mahesh

    2018-01-01

    Compared to most other planetary materials in the Solar System, some lunar rocks display high δ37Cl signatures. Loss of Cl in a H Cl environment has been invoked to explain the heavy signatures observed in lunar samples, either during volcanic eruptions onto the lunar surface or during large scale

  20. Lunar imaging and ionospheric calibration for the Lunar Cherenkov technique

    NARCIS (Netherlands)

    McFadden, R.; Scholten, O.; Mevius, M.

    2013-01-01

    The Lunar Cherenkov technique is a promising method for UHE neutrino and cosmic ray detection which aims to detect nanosecond radio pulses produced during particle interactions in the Lunar regolith. For low frequency experiments, such as NuMoon, the frequency dependent dispersive effect of the

  1. Lunar Impact Flash Locations from NASA's Lunar Impact Monitoring Program

    Science.gov (United States)

    Moser, D. E.; Suggs, R. M.; Kupferschmidt, L.; Feldman, J.

    2015-01-01

    Meteoroids are small, natural bodies traveling through space, fragments from comets, asteroids, and impact debris from planets. Unlike the Earth, which has an atmosphere that slows, ablates, and disintegrates most meteoroids before they reach the ground, the Moon has little-to-no atmosphere to prevent meteoroids from impacting the lunar surface. Upon impact, the meteoroid's kinetic energy is partitioned into crater excavation, seismic wave production, and the generation of a debris plume. A flash of light associated with the plume is detectable by instruments on Earth. Following the initial observation of a probable Taurid impact flash on the Moon in November 2005,1 the NASA Meteoroid Environment Office (MEO) began a routine monitoring program to observe the Moon for meteoroid impact flashes in early 2006, resulting in the observation of over 330 impacts to date. The main objective of the MEO is to characterize the meteoroid environment for application to spacecraft engineering and operations. The Lunar Impact Monitoring Program provides information about the meteoroid flux in near-Earth space in a size range-tens of grams to a few kilograms-difficult to measure with statistical significance by other means. A bright impact flash detected by the program in March 2013 brought into focus the importance of determining the impact flash location. Prior to this time, the location was estimated to the nearest half-degree by visually comparing the impact imagery to maps of the Moon. Better accuracy was not needed because meteoroid flux calculations did not require high-accuracy impact locations. But such a bright event was thought to have produced a fresh crater detectable from lunar orbit by the NASA spacecraft Lunar Reconnaissance Orbiter (LRO). The idea of linking the observation of an impact flash with its crater was an appealing one, as it would validate NASA photometric calculations and crater scaling laws developed from hypervelocity gun testing. This idea was

  2. Sandmeier model based topographic correction to lunar spectral profiler (SP) data from KAGUYA satellite.

    Science.gov (United States)

    Chen, Sheng-Bo; Wang, Jing-Ran; Guo, Peng-Ju; Wang, Ming-Chang

    2014-09-01

    The Moon may be considered as the frontier base for the deep space exploration. The spectral analysis is one of the key techniques to determine the lunar surface rock and mineral compositions. But the lunar topographic relief is more remarkable than that of the Earth. It is necessary to conduct the topographic correction for lunar spectral data before they are used to retrieve the compositions. In the present paper, a lunar Sandmeier model was proposed by considering the radiance effect from the macro and ambient topographic relief. And the reflectance correction model was also reduced based on the Sandmeier model. The Spectral Profile (SP) data from KAGUYA satellite in the Sinus Iridum quadrangle was taken as an example. And the digital elevation data from Lunar Orbiter Laser Altimeter are used to calculate the slope, aspect, incidence and emergence angles, and terrain-viewing factor for the topographic correction Thus, the lunar surface reflectance from the SP data was corrected by the proposed model after the direct component of irradiance on a horizontal surface was derived. As a result, the high spectral reflectance facing the sun is decreased and low spectral reflectance back to the sun is compensated. The statistical histogram of reflectance-corrected pixel numbers presents Gaussian distribution Therefore, the model is robust to correct lunar topographic effect and estimate lunar surface reflectance.

  3. Luna-Glob project in the context of the past and present lunar ...

    Indian Academy of Sciences (India)

    seen before. In 1962–1965 America sent several spacecrafts of the Ranger series to the Moon. A significant achievement came when Luna 9 made the first soft landing and provided a TV-panorama of the lunar surface. In 1968, Zond 5 and Zond 6 were the first lunar flyby with biological objects and safely returned to Earth.

  4. High-Resolution Spectroscopy of the Lunar Sodium Exosphere

    Science.gov (United States)

    Mierkiewicz, E. J.; Oliversen, R. J.; Roesler, F. L.; Lupie, O. L.

    2014-01-01

    We have applied high-resolution Fabry-Perot spectroscopy to the study of the lunar sodium exosphere for the study of exospheric effective temperature and velocity variations. Observing from the National Solar Observatory McMath-Pierce Telescope, we used a dual-etalon Fabry-Perot spectrometer with a resolving power of 180,000 to measure line widths and Doppler shifts of the sodium D2 (5889.95 Å) emission line. Our field of view was 360 km, and measurements were made in equatorial and polar regions from 500 km to 3500 km off the limb. Data were obtained from full moon to 3 days following full moon (waning phase) in March 2009. Measured Doppler line widths within 1100 km of the sunlit east and south lunar limbs for observations between 5 and 40 deg lunar phase imply effective temperatures ranging between 3260 +/- 190 and 1000 +/- 135 K. Preliminary line center analysis indicates velocity displacements between different locations off the lunar limb ranging between 100 and 600 m/s from the lunar rest velocity with a precision of +/-20 to +/-50 m/s depending on brightness. Based on the success of these exploratory observations, an extensive program has been initiated that is expected to constrain lunar atmospheric and surface-process modeling and help quantify source and escape mechanisms.

  5. Geochemistry of Lunar Highland Meteorites Mil, 090034, 090036 AND 090070

    Science.gov (United States)

    Shirai, N.aoki; Ebihara, M.; Sekimoto, S.; Yamaguchi, A.; Nyquist, L.; Shih, C.-Y.; Park, J.; Nagao, K.

    2012-01-01

    Apollo and Luna samples were collected from a restricted area on the near side of the Moon, while the source craters of the lunar meteorites are randomly distributed. For example, Takeda et al. [1] and Yamaguchi et al. [2] found a variety of lithic clasts in Dho 489 and Y 86032 which were not represented by Apollo samples, and some of these clasts have lower rare earth elements (REE) and FeO abundances than Apollo anorthosites, respectively. Takeda et al. [1] and Yamaguchi et al. [2] concluded that Dho 489 and Y 86032 originated from the lunar farside. Therefore, lunar meteorites provide an opportunity to study lunar surface rocks from areas not sampled by Apollo and Luna missions. Three lunar anorthitic breccias (MIL 090034, 090036 and 090070) were found on the Miller Range Ice Field in Antarctica during the 2009-2010 ANSMET season [3]. In this study, we determined elemental abudnances for MIL 090034, 090036 and 090070 by using INAA and aimed to characterize these meteorites in chemical compositions in comparison with those for other lunar meteorites and Apollo samples.

  6. The crystal structure of Haloferax volcanii proliferating cell nuclear antigen reveals unique surface charge characteristics due to halophilic adaptation

    Directory of Open Access Journals (Sweden)

    Morroll Shaun

    2009-08-01

    Full Text Available Abstract Background The high intracellular salt concentration required to maintain a halophilic lifestyle poses challenges to haloarchaeal proteins that must stay soluble, stable and functional in this extreme environment. Proliferating cell nuclear antigen (PCNA is a fundamental protein involved in maintaining genome integrity, with roles in both DNA replication and repair. To investigate the halophilic adaptation of such a key protein we have crystallised and solved the structure of Haloferax volcanii PCNA (HvPCNA to a resolution of 2.0 Å. Results The overall architecture of HvPCNA is very similar to other known PCNAs, which are highly structurally conserved. Three commonly observed adaptations in halophilic proteins are higher surface acidity, bound ions and increased numbers of intermolecular ion pairs (in oligomeric proteins. HvPCNA possesses the former two adaptations but not the latter, despite functioning as a homotrimer. Strikingly, the positive surface charge considered key to PCNA's role as a sliding clamp is dramatically reduced in the halophilic protein. Instead, bound cations within the solvation shell of HvPCNA may permit sliding along negatively charged DNA by reducing electrostatic repulsion effects. Conclusion The extent to which individual proteins adapt to halophilic conditions varies, presumably due to their diverse characteristics and roles within the cell. The number of ion pairs observed in the HvPCNA monomer-monomer interface was unexpectedly low. This may reflect the fact that the trimer is intrinsically stable over a wide range of salt concentrations and therefore additional modifications for trimer maintenance in high salt conditions are not required. Halophilic proteins frequently bind anions and cations and in HvPCNA cation binding may compensate for the remarkable reduction in positive charge in the pore region, to facilitate functional interactions with DNA. In this way, HvPCNA may harness its environment as

  7. The crystal structure of Haloferax volcanii proliferating cell nuclear antigen reveals unique surface charge characteristics due to halophilic adaptation

    Science.gov (United States)

    Winter, Jody A; Christofi, Panayiotis; Morroll, Shaun; Bunting, Karen A

    2009-01-01

    Background The high intracellular salt concentration required to maintain a halophilic lifestyle poses challenges to haloarchaeal proteins that must stay soluble, stable and functional in this extreme environment. Proliferating cell nuclear antigen (PCNA) is a fundamental protein involved in maintaining genome integrity, with roles in both DNA replication and repair. To investigate the halophilic adaptation of such a key protein we have crystallised and solved the structure of Haloferax volcanii PCNA (HvPCNA) to a resolution of 2.0 Å. Results The overall architecture of HvPCNA is very similar to other known PCNAs, which are highly structurally conserved. Three commonly observed adaptations in halophilic proteins are higher surface acidity, bound ions and increased numbers of intermolecular ion pairs (in oligomeric proteins). HvPCNA possesses the former two adaptations but not the latter, despite functioning as a homotrimer. Strikingly, the positive surface charge considered key to PCNA's role as a sliding clamp is dramatically reduced in the halophilic protein. Instead, bound cations within the solvation shell of HvPCNA may permit sliding along negatively charged DNA by reducing electrostatic repulsion effects. Conclusion The extent to which individual proteins adapt to halophilic conditions varies, presumably due to their diverse characteristics and roles within the cell. The number of ion pairs observed in the HvPCNA monomer-monomer interface was unexpectedly low. This may reflect the fact that the trimer is intrinsically stable over a wide range of salt concentrations and therefore additional modifications for trimer maintenance in high salt conditions are not required. Halophilic proteins frequently bind anions and cations and in HvPCNA cation binding may compensate for the remarkable reduction in positive charge in the pore region, to facilitate functional interactions with DNA. In this way, HvPCNA may harness its environment as opposed to simply surviving in

  8. Colour Changes on the Surface of the Rock Materials Due to UV-A and UV-B Rays

    Science.gov (United States)

    Binal, Adil; Ayderman, Aykut; Sel, Aylin

    2015-04-01

    The colour of the rocks used in the current buildings, and historical monuments is an important parameter in architecture and engineering. In addition, engineering geologists use the colour in order to identify the weathering class of rock material. The main colour of the stone, especially, are affected by the mineral size, the colour of the primary minerals and matrix material, as well as the colour of the accessory minerals. Due to atmospheric effects, changes in the outer surface colour of the rocks used as siding materials occur with over time. Factors causing the colour change are carbon dioxide (CO2), ozone (O3), sulphate (SO2, SO3) and nitrate (NOx) from the atmosphere with aerosols as well as UV rays from the sun. There is no more work in the literature on colour changes caused by UV-A and UV-B rays. In this study, the effects of ultraviolet in the colour of the surfaces of basalt, limestone, ignimbrite, travertine and sandstone have been simulated with a new experimental device in the laboratory medium. Lutron colour analyser (RGB-1002) was used for the measurements of RGB colours. Colour differences between the beginning and end of tests were determined with the standard practice for calculation of colour tolerances and colour differences from instrumentally measured colour coordinates (ASTM D2244). As a result of the experiments performed, lighten that seem on dark-grey micritic limestone (colour change ratio, CCR: 17.06) and basalt samples (CCR: 8.24) become even visually noticeable. Black and red ignimbrite samples having high porosity were presented the lower rate of colour changes. Finally, colour darkening has been observed in the light-coloured travertine (CCR: 13.8) and sandstone samples (CCR: 20.99).

  9. The Use of Numerical Modeling to Address Surface and Subsurface Water Contamination due to Fracwater Spills in Larry's Creek, Pennsylvania

    Science.gov (United States)

    Simon, C. A.; Arjmand, S.; Abad, J. D.

    2012-12-01

    Because of its relatively low carbon dioxide emissions, natural gas is considered to be more efficient and environmentally friendly than other non-renewable fuels. As a result of this, among other factors, in recent years natural gas has become one of the world's primary energy sources. In the United States, drilling to extract natural gas has substantially increased over the past few years. In the Marcellus Shale, unconventional gas is currently extracted by using two new techniques: horizontal drilling and hydraulic fracturing. Today, fracking fluids which have been applied as part of the hydraulic fracturing process to fracture the shale rock and release the gas, pose a major environmental concern. These fluids are highly contaminated with radionuclides and toxic metals and any exposure of this highly polluted water to surface water or soil could heavily contaminate the media. The area selected for the current study is the Larry's Creek, located in Lycoming County in Pennsylvania. Larry's Creek Watershed was adversely affected by coal and iron mines activities in the 19th century. Though, the water quality in this creek was considered to be good as of 2006. Recently, oil and gas drilling activities have raised concerns about the creek's water quality again. A major environmental hazard is the freshwater contamination by frac/flowback water. Drilling companies are using impoundments on site to keep fracwater, and to store and evaporate flowback water. However, these ponds may fail or leak due to construction problems and/or accidents. Close to Saladasburg, Larry's Creek's stream was observed running rich with clay in October 19, 2011. Historical measurements show very high turbidity during this period which has raised questions about water contamination by the gas industry activities in the upper stream of the watershed. An interstate watershed agency has reported spills in Wolf Run in different drilling sites in the Larry's Creek basin. The focus of this study

  10. Uncertainties in surface mass and energy flux estimates due to different eddy covariance sensors and technical set-up

    Science.gov (United States)

    Arriga, Nicola; Fratini, Gerardo; Forgione, Antonio; Tomassucci, Michele; Papale, Dario

    2010-05-01

    Eddy covariance is a well established and widely used methodology for the measurement of turbulent fluxes of mass and energy in the atmospheric boundary layer, in particular to estimate CO2/H2O and heat exchange above ecologically relevant surfaces (Aubinet 2000, Baldocchi 2003). Despite its long term application and theoretical studies, many issues are still open about the effect of different experimental set-up on final flux estimates. Open issues are the evaluation of the performances of different kind of sensors (e.g. open path vs closed path infra-red gas analysers, vertical vs horizontal mounting ultrasonic anemometers), the quantification of the impact of corresponding physical corrections to be applied to get robust flux estimates taking in account all processes concurring to the measurement (e.g. the so-called WPL term, signal attenuation due to air sampling system for closed path analyser, relative position of analyser and anemometer) and the differences between several data transmission protocols used (analogue, digital RS-232, SDM). A field experiment was designed to study these issues using several instruments among those most used within the Fluxnet community and to compare their performances under conditions supposed to be critical: rainy and cold weather conditions for open-path analysers (Burba 2008), water transport and absorption at high air relative humidity conditions for closed-path systems (Ibrom, 2007), frequency sampling limits and recorded data robustness due to different transmission protocols (RS232, SDM, USB, Ethernet) and finally the effect of the displacement between anemometer and analyser using at least two identical analysers placed at different horizontal and vertical distances from the anemometer. Aim of this experiment is to quantify the effect of several technical solutions on the final estimates of fluxes measured at a point in the space and if they represent a significant source of uncertainty for mass and energy cycle

  11. Restoration of Apollo Data by the Lunar Data Project/PDS Lunar Data Node: An Update

    Science.gov (United States)

    Williams, David R.; Hills, H. Kent; Taylor, Patrick T.; Grayzeck, Edwin J.; Guinness, Edward A.

    2016-01-01

    The Apollo 11, 12, and 14 through 17 missions orbited and landed on the Moon, carrying scientific instruments that returned data from all phases of the missions, included long-lived Apollo Lunar Surface Experiments Packages (ALSEPs) deployed by the astronauts on the lunar surface. Much of these data were never archived, and some of the archived data were on media and in formats that are outmoded, or were deposited with little or no useful documentation to aid outside users. This is particularly true of the ALSEP data returned autonomously for many years after the Apollo missions ended. The purpose of the Lunar Data Project and the Planetary Data System (PDS) Lunar Data Node is to take data collections already archived at the NASA Space Science Data Coordinated Archive (NSSDCA) and prepare them for archiving through PDS, and to locate lunar data that were never archived, bring them into NSSDCA, and then archive them through PDS. Preparing these data for archiving involves reading the data from the original media, be it magnetic tape, microfilm, microfiche, or hard-copy document, converting the outmoded, often binary, formats when necessary, putting them into a standard digital form accepted by PDS, collecting the necessary ancillary data and documentation (metadata) to ensure that the data are usable and well-described, summarizing the metadata in documentation to be included in the data set, adding other information such as references, mission and instrument descriptions, contact information, and related documentation, and packaging the results in a PDS-compliant data set. The data set is then validated and reviewed by a group of external scientists as part of the PDS final archive process. We present a status report on some of the data sets that we are processing.

  12. KOREAN LUNAR LANDER – CONCEPT STUDY FOR LANDING-SITE SELECTION FOR LUNAR RESOURCE EXPLORATION

    Directory of Open Access Journals (Sweden)

    K. J. Kim

    2016-06-01

    Full Text Available As part of the national space promotion plan and presidential national agendas South Korea’s institutes and agencies under the auspices of the Ministry of Science, Information and Communication Technology and Future Planning (MSIP are currently developing a lunar mission package expected to reach Moon in 2020. While the officially approved Korean Pathfinder Lunar Orbiter (KPLO is aimed at demonstrating technologies and monitoring the lunar environment from orbit, a lander – currently in pre-phase A – is being designed to explore the local geology with a particular focus on the detection and characterization of mineral resources. In addition to scientific and potential resource potentials, the selection of the landing-site will be partly constrained by engineering constraints imposed by payload and spacecraft layout. Given today’s accumulated volume and quality of available data returned from the Moon’s surface and from orbital observations, an identification of landing sites of potential interest and assessment of potential hazards can be more readily accomplished by generating synoptic snapshots through data integration. In order to achieve such a view on potential landing sites, higher level processing and derivation of data are required, which integrates their spatial context, with detailed topographic and geologic characterizations. We are currently assessing the possibility of using fuzzy c-means clustering algorithms as a way to perform (semi- automated terrain characterizations of interest. This paper provides information and background on the national lunar lander program, reviews existing approaches – including methods and tools – for landing site analysis and hazard assessment, and discusses concepts to detect and investigate elemental abundances from orbit and the surface. This is achieved by making use of manual, semi-automated as well as fully-automated remote-sensing methods to demonstrate the applicability of

  13. The negligible chondritic contribution in the lunar soils water.

    Science.gov (United States)

    Stephant, Alice; Robert, François

    2014-10-21

    Recent data from Apollo samples demonstrate the presence of water in the lunar interior and at the surface, challenging previous assumption that the Moon was free of water. However, the source(s) of this water remains enigmatic. The external flux of particles and solid materials that reach the surface of the airless Moon constitute a hydrogen (H) surface reservoir that can be converted to water (or OH) during proton implantation in rocks or remobilization during magmatic events. Our original goal was thus to quantify the relative contributions to this H surface reservoir. To this end, we report NanoSIMS measurements of D/H and (7)Li/(6)Li ratios on agglutinates, volcanic glasses, and plagioclase grains from the Apollo sample collection. Clear correlations emerge between cosmogenic D and (6)Li revealing that almost all D is produced by spallation reactions both on the surface and in the interior of the grains. In grain interiors, no evidence of chondritic water has been found. This observation allows us to constrain the H isotopic ratio of hypothetical juvenile lunar water to δD ≤ -550‰. On the grain surface, the hydroxyl concentrations are significant and the D/H ratios indicate that they originate from solar wind implantation. The scattering distribution of the data around the theoretical D vs. (6)Li spallation correlation is compatible with a chondritic contribution lunar surface, and (ii) the postulated chondritic lunar water is not retained in the regolith.

  14. Creating Methane from Plastics: Recycling at a Lunar Outpost

    Science.gov (United States)

    Captain, Janine; Santiago, Eddie; Wheeler, Ray; Strayer, RIchard; Garland, Jay; Parrish, Clyde

    2010-01-01

    The high cost of re-supply from Earth demands resources to be utilized to the fullest extent for exploration missions. Recycling is a key technology that maximizes the available resources by converting waste products into useful commodities. One example of this is to convert crew member waste such as plastic packaging, food scraps, and human waste, into fuel. The ability to refuel on the lunar surface would reduce the vehicle mass during launch and provide excess payload capability. The goal of this project is to determine the feasibility of recycling waste into methane on the lunar outpost by performing engineering assessments and lab demonstrations of the technology. The first goal of the project was to determine how recycling could influence lunar exploration. Table I shows an estimation of the typical dried waste stream generated each day for a crew of four. Packaging waste accounts for nearly 86% of the dry waste stream and is a significant source of carbon on the lunar surface. This is important because methane (CH4) can be used as fuel and no other source of carbon is available on the lunar surface. With the initial assessment indicating there is sufficient resources in the waste stream to provide refueling capabilities, the project was designed to examine the conversion of plastics into methane.

  15. The Kaguya Lunar Atlas The Moon in High Resolution