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Sample records for lunar crust sir

  1. Chronology of early lunar crust

    International Nuclear Information System (INIS)

    Dasch, E.J.; Nyquist, L.E.; Ryder, G.

    1988-01-01

    The chronology of lunar rocks is summarized. The oldest pristine (i.e., lacking meteoritic contamination of admixed components) lunar rock, recently dated with Sm-Nd by Lugmair, is a ferroan anorthosite, with an age of 4.44 + 0.02 Ga. Ages of Mg-suite rocks (4.1 to 4.5 Ga) have large uncertainties, so that age differences between lunar plutonic rock suites cannot yet be resolved. Most mare basalts crystallized between 3.1 and 3.9 Ga. The vast bulk of the lunar crust, therefore, formed before the oldest preserved terrestrial rocks. If the Moon accreted at 4.56 Ga, then 120 Ma may have elapsed before lunar crust was formed

  2. 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

  3. The Stratigraphy and Evolution of the Lunar Crust

    Science.gov (United States)

    McCallum, I. Stewart

    1998-01-01

    Reconstruction of stratigraphic relationships in the ancient lunar crust has proved to be a formidable task. The intense bombardment during the first 700 m.y. of lunar history has severely perturbed the original stratigraphy and destroyed the primary textures of all but a few nonmare rocks. However, a knowledge of the crustal stratigraphy as it existed prior to the cataclysmic bombardment about 3.9 Ga is essential to test the major models proposed for crustal origin, i.e., crystal fractionation in a global magmasphere or serial magmatism in a large number of smaller bodies. Despite the large difference in scale implicit in these two models, both require an efficient separation of plagioclase and mafic minerals to form the anorthositic crust and the mafic mantle. Despite the havoc wreaked by the large body impactors, these same impact processes have brought to the lunar surface crystalline samples derived from at least the upper half of the lunar crust, thereby providing an opportunity to reconstruct the stratigraphy in areas sampled by the Apollo missions. As noted, ejecta from the large multiring basins are dominantly, or even exclusively, of crustal origin. Given the most recent determinations of crustal thicknesses, this implies an upper limit to the depth of excavation of about 60 km. Of all the lunar samples studied, a small set has been recognized as "pristine", and within this pristine group, a small fraction have retained some vestiges of primary features formed during the earliest stages of crystallization or recrystallization prior to 4.0 Ga. We have examined a number of these samples that have retained some record of primary crystallization to deduce thermal histories from an analysis of structural, textural, and compositional features in minerals from these samples. Specifically, by quantitative modeling of (1) the growth rate and development of compositional profiles of exsolution lamellae in pyroxenes and (2) the rate of Fe-Mg ordering in

  4. 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.

  5. Crystallization Age and Impact Resetting of Ancient Lunar Crust from the Descartes Terrane

    Science.gov (United States)

    Norman, M. D.; Borg, L. E.; Nyquist, L. E.; Bogard, D. D.

    2002-01-01

    Lunar ferroan anorthosites (FANs) are relics of an ancient, primary feldspathic crust that is widely believed to have crystallized from a global magma ocean. Compositions and ages of FANs provide fundamental information about the origin and magmatic evolution of the Moon, while the petrology and thermal history of lunar FANs illustrate the structure and impact history of the lunar crust. Here we report petrologic, geochemical, and isotopic (Nd-Sr-Ar) studies of a ferroan noritic anorthosite clast from lunar breccia 67215 to improve our understanding of the composition, age, and thermal history of the Moon.

  6. Asymmetric Post-Magma Ocean Crust-Building on the Lunar Nearside

    Science.gov (United States)

    Elardo, S. M.; Laneuville, M.; McCubbin, F. M.; Shearer, C. K.

    2018-05-01

    Our experiments show that the KREEP reservoir on the lunar nearside reduces the melting temperature of Mg-suite source rocks, leading to asymmetric crust-building magmatism independent of any contribution from radiogenic heating.

  7. Osmium isotope and highly siderophile element systematics of the lunar crust

    Science.gov (United States)

    Day, J.M.D.; Walker, R.J.; James, O.B.; Puchtel, I.S.

    2010-01-01

    Coupled 187Os/188Os and highly siderophile element (HSE: Os, Ir, Ru, Pt, Pd, and Re) abundance data are reported for pristine lunar crustal rocks 60025, 62255, 65315 (ferroan anorthosites, FAN) and 76535, 78235, 77215 and a norite clast in 15455 (magnesian-suite rocks, MGS). Osmium isotopes permit more refined discrimination than previously possible of samples that have been contaminated by meteoritic additions and the new results show that some rocks, previously identified as pristine, contain meteorite-derived HSE. Low HSE abundances in FAN and MGS rocks are consistent with derivation from a strongly HSE-depleted lunar mantle. At the time of formation, the lunar floatation crust, represented by FAN, had 1.4 ?? 0.3 pg g- 1 Os, 1.5 ?? 0.6 pg g- 1 Ir, 6.8 ?? 2.7 pg g- 1 Ru, 16 ?? 15 pg g- 1 Pt, 33 ?? 30 pg g- 1 Pd and 0.29 ?? 0.10 pg g- 1 Re (??? 0.00002 ?? CI) and Re/Os ratios that were modestly elevated (187Re/188Os = 0.6 to 1.7) relative to CI chondrites. MGS samples are, on average, characterised by more elevated HSE abundances (??? 0.00007 ?? CI) compared with FAN. This either reflects contrasting mantle-source HSE characteristics of FAN and MGS rocks, or different mantle-crust HSE fractionation behaviour during production of these lithologies. Previous studies of lunar impact-melt rocks have identified possible elevated Ru and Pd in lunar crustal target rocks. The new results provide no supporting evidence for such enrichments. If maximum estimates for HSE in the lunar mantle are compared with FAN and MGS averages, crust-mantle concentration ratios (D-values) must be ??? 0.3. Such D-values are broadly similar to those estimated for partitioning between the terrestrial crust and upper mantle, with the notable exception of Re. Given the presumably completely different mode of origin for the primary lunar floatation crust and tertiary terrestrial continental crust, the potential similarities in crust-mantle HSE partitioning for the Earth and Moon are somewhat

  8. 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

  9. Small-scale density variations in the lunar crust revealed by GRAIL

    Science.gov (United States)

    Jansen, J. C.; Andrews-Hanna, J. C.; Li, Y.; Lucey, P. G.; Taylor, G. J.; Goossens, S.; Lemoine, F. G.; Mazarico, E.; Head, J. W.; Milbury, C.; Kiefer, W. S.; Soderblom, J. M.; Zuber, M. T.

    2017-07-01

    Data from the Gravity Recovery and Interior Laboratory (GRAIL) mission have revealed that ∼98% of the power of the gravity signal of the Moon at high spherical harmonic degrees correlates with the topography. The remaining 2% of the signal, which cannot be explained by topography, contains information about density variations within the crust. These high-degree Bouguer gravity anomalies are likely caused by small-scale (10‧s of km) shallow density variations. Here we use gravity inversions to model the small-scale three-dimensional variations in the density of the lunar crust. Inversion results from three non-descript areas yield shallow density variations in the range of 100-200 kg/m3. Three end-member scenarios of variations in porosity, intrusions into the crust, and variations in bulk crustal composition were tested as possible sources of the density variations. We find that the density anomalies can be caused entirely by changes in porosity. Characteristics of density anomalies in the South Pole-Aitken basin also support porosity as a primary source of these variations. Mafic intrusions into the crust could explain many, but not all of the anomalies. Additionally, variations in crustal composition revealed by spectral data could only explain a small fraction of the density anomalies. Nevertheless, all three sources of density variations likely contribute. Collectively, results from this study of GRAIL gravity data, combined with other studies of remote sensing data and lunar samples, show that the lunar crust exhibits variations in density by ± 10% over scales ranging from centimeters to 100‧s of kilometers.

  10. Small-Scale Density Variations in the Lunar Crust Revealed by GRAIL

    Science.gov (United States)

    Jansen, J. C.; Andrews-Hanna, J. C.; Li, Y.; Lucey, P. G.; Taylor, G. J.; Goossens, S.; Lemoine, F. G.; Mazarico, E.; Head, J. W., III; Milbury, C.; hide

    2017-01-01

    Data from the Gravity Recovery and Interior Laboratory (GRAIL) mission have revealed that approximately 98 percent of the power of the gravity signal of the Moon at high spherical harmonic degrees correlates with the topography. The remaining 2 percent of the signal, which cannot be explained by topography, contains information about density variations within the crust. These high-degree Bouguer gravity anomalies are likely caused by small-scale (10's of km) shallow density variations. Here we use gravity inversions to model the small-scale three-dimensional variations in the density of the lunar crust. Inversion results from three non-descript areas yield shallow density variations in the range of 100-200 kg/m3. Three end-member scenarios of variations in porosity, intrusions into the crust, and variations in bulk crustal composition were tested as possible sources of the density variations. We find that the density anomalies can be caused entirely by changes in porosity. Characteristics of density anomalies in the South Pole-Aitken basin also support porosity as a primary source of these variations. Mafic intrusions into the crust could explain many, but not all of the anomalies. Additionally, variations in crustal composition revealed by spectral data could only explain a small fraction of the density anomalies. Nevertheless, all three sources of density variations likely contribute. Collectively, results from this study of GRAIL gravity data, combined with other studies of remote sensing data and lunar samples, show that the lunar crust exhibits variations in density by plus or minus 10 percent over scales ranging from centimeters to 100’s of kilometers.

  11. Spinel-rich lithologies in the lunar highland crust: Linking lunar samples, crystallization experiments and remote sensing

    Science.gov (United States)

    Gross, J.; Treiman, A. H.

    2012-12-01

    The discovery of areas rich in (Mg,Fe)-Al spinel on the rims and central peaks of lunar impact basins (by the M3 mapping spectrometer on Chandrayaan-1) has revived the old puzzle of the origin of lunar spinel. (Mg,Fe)-Al spinel is rare but widespread in lunar highlands rocks, and thus might be an important component of the lunar crust [1-3]. However, the origin of this spinel is not clear. Lunar (Mg,Fe)-Al spinel could have formed (1) during 'normal' basalt petrogenesis at high pressure; (2) during low-pressure crystallization of melts rich in olivine and plagioclase components, e.g. impact-melted lunar troctolite; or (3) formed at low pressure during assimilation of anorthosite into picritic magma; thus, lunar spinel-rich areas represent old (pre-impact) intrusions of magma. In the absence of spinel-rich samples from the Moon, however, these ideas have been highly speculative. Here we describe a rock fragment from lunar meteorite ALHA 81005 that we recently reported [4] that not only contains spinel, but is the first spinel-rich lunar sample described. This fragment contains ~30% (Mg,Fe)Al spinel and is so fine grained that it reasonably could represent a larger rock body. However, the fragment is so rich in spinel that it could not have formed by melting a peridotitic mantle or a basaltic lunar crust. The clast's small grain size and its apparent disequilibrium between spinel and pyroxene suggest fairly rapid crystallization at low pressure. It could have formed as a spinel cumulate from an impact melt of troctolitic composition; or from a picritic magma that assimilated crustal anorthosite on its margins. The latter mechanism is preferred because it explains the petrographic and chemical features of our clast, and is consistent with the regional setting of the Moscoviense spinel deposit [4]. To better understand the origin and formation history(s) of spinel-rich rocks, we also performed liquidus/crystallization experiments at low-pressure as analogues for impact

  12. Can Fractional Crystallization of a Lunar Magma Ocean Produce the Lunar Crust?

    Science.gov (United States)

    Rapp, Jennifer F.; Draper, David S.

    2013-01-01

    New techniques enable the study of Apollo samples and lunar meteorites in unprecedented detail, and recent orbital spectral data reveal more about the lunar farside than ever before, raising new questions about the supposed simplicity of lunar geology. Nevertheless, crystallization of a global-scale magma ocean remains the best model to account for known lunar lithologies. Crystallization of a lunar magma ocean (LMO) is modeled to proceed by two end-member processes - fractional crystallization from (mostly) the bottom up, or initial equilibrium crystallization as the magma is vigorously convecting and crystals remain entrained, followed by crystal settling and a final period of fractional crystallization [1]. Physical models of magma viscosity and convection at this scale suggest that both processes are possible. We have been carrying out high-fidelity experimental simulations of LMO crystallization using two bulk compositions that can be regarded as end-members in the likely relevant range: Taylor Whole Moon (TWM) [2] and Lunar Primitive Upper Mantle (LPUM) [3]. TWM is enriched in refractory elements by 1.5 times relative to Earth, whereas LPUM is similar to the terrestrial primitive upper mantle, with adjustments made for the depletion of volatile alkalis observed on the Moon. Here we extend our earlier equilibrium-crystallization experiments [4] with runs simulating full fractional crystallization

  13. Lunar evolution: is there a global radioactive crust on the moon

    International Nuclear Information System (INIS)

    Murthy, V.R.

    1977-01-01

    Chemical and isotopic analyses of various grainsize fractions of lunar soils show the presence of an 'exotic component' in practically all lunar soils. The patterns of enrichments in the grain-size fractions and the Sr-isotopic data show that the regolith evolution displays the combined effects of comminution of local rock types and addition of the exotic component. The chemical characteristics of this exotic component as deduced from the chemical and isotopic data in soils from Apollo 11, 12, 15 and 16 uniformly point to compositions similar to the material from Fra Mauro region collected in the Apollo 14 mission. There is a strong correlation between the amount of exotic component in a soil and its distance from the Fra Mauro region. It is suggested that the exotic component represents trace element enriched material from the Imbrium-Procellarum region, which was surficially deposited during Imbrium excavation and re-exposed from under the mare-lavas in subsequent cratering events. Surficial transport processes have distributed these materials widely over the lunar surface. There appears no need to invoke a global radioactive crust on the Moon nor of 'hot spots' distributed over the entire surface of the Moon to explain the ubiquitous presence of this component in lunar regolith, nor is there a compelling reason at present to postulate a global melting process for the generation of highly differentiated materials such as 'kreep' and the exotic component. (author)

  14. The granulite suite: Impact melts and metamorphic breccias of the early lunar crust

    Science.gov (United States)

    Cushing, J. A.; Taylor, G. J.; Norman, M. D.; Keil, K.

    1993-03-01

    The granulite suite consists of two major types of rocks. One is coarse-grained and poikilitic with many euhedral crystals of olivine and plagioclase. These characteristics indicate crystallization from a melt; the poikilitic granulites are impact melt breccias. The other group is finer-grained and granoblastic, with numerous triple junctions; the granoblastic granulites are metamorphic rocks. Compositional groups identified by Lindstrom and Lindstrom contain both textural types. Two pyroxene thermometry indicates that both groups equilibrated at 1000 to 1150 C. Calculations suggest that the granoblastic group, which has an average grain size of about 80 microns, was annealed for less than 6 x 10 exp 4 y at 1000 C, and for less than 2500 y at 1150 C. Similar equilibration temperatures suggest that both groups were physically associated after impact events produced the poikilitic melts. Granulitic impactites hold important information about the pre-Nectarian bombardment history of the Moon, and the composition and thermal evolution of the early lunar crust. Granulitic impactites are widely considered to be an important rock type in the lunar crust, but how they formed is poorly understood. Metal compositions and elevated concentrations of meteoritic siderophile elements suggest that most lunar granulites are impact breccias. Their occurrence as clasts in approximately 3.9 Ga breccias, and Ar-(40-39) ages greater than or = 4.2 Ga for some granulites show that they represent a component of the lunar crust which formed prior to the Nectarian cataclysm. Petrographic characteristics of lunar granulites indicate at least two endmember textural variants which apparently formed in fundamentally different ways. One type has granoblastic textures consisting of equant, polygonal to rounded grains, and abundant triple junctions with small dispersions around 120 degrees indicating a close approach to textural equilibrium. As suggested by many authors, granoblastic granulites

  15. 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.

  16. A survey of lunar rock types and comparison of the crusts of earth and moon

    Science.gov (United States)

    Wood, J. A.

    1977-01-01

    The principal known types of lunar rocks are briefly reviewed, and their chemical relationships discussed. In the suite of low-KREEP highland rocks, Fe/(Fe + Mg) in the normative mafic minerals increases and the albite content of normative plagio-clase decreases as the total amount of normative plagioclase increases, the opposite of the trend predicted by the Bowen reaction principle. The distribution of compositions of rocks from terrestrial layered mafic intrusives is substantially different: here the analyses fall in several discrete clusters (anorthositic rocks, norites, granophyres and ferrogabbros, ultramafics), and the chemical trends noted above are not reproduced. It is suggested that the observed trends in lunar highland rocks could be produced by crystal fractionation in a deep global surface magma system if (1) plagiociase tended to float, upon crystallization, and (2) the magma was kept agitated and well mixed (probably by thermal convection) until crystallization was far advanced and relatively little residual liquid was left. After the crustal system solidified, but before extensive cooling had developed a thick, strong lithosphere, mantle convection was able to draw portions of the lunar anorthositic crust down into the mantle.

  17. Lunar mare volcanism - Stratigraphy, eruption conditions, and the evolution of secondary crusts

    Science.gov (United States)

    Head, James W., III; Wilson, Lionel

    1992-01-01

    Recent developments in the geological analysis of lunar mare volcanism are reviewed. Analysis of returned samples and photogeological and remote sensing studies shows that mare volcanism began prior to the end of heavy bombardment (the period of cryptomare formation), in pre-Nectarian times, and continued until the Copernical Period, the total duration approaching 3.5-4 Ga. Stratigraphic analysis shows that the flux was not constant, but peaked in early lunar history, during the Imbrian Period. Average volcanic output rate during this period was about 0.01 cu cm/a. Volcanic landforms indicate that many eruptions were of high volume and long duration. Some eruptions associated with sinuous rills may have lasted a year and emplaced 1000 cu km of lava, representing the equivalent in one year of about 70,000 yr at the average flux. The occurrence of farside maria within craters whose diameter is generally near to or less than the thickness of the crust may be accounted for by the difference between local and regional compensation.

  18. A Low Viscosity Lunar Magma Ocean Forms a Stratified Anorthitic Flotation Crust With Mafic Poor and Rich Units: Lunar Magma Ocean Viscosity

    Energy Technology Data Exchange (ETDEWEB)

    Dygert, Nick [Department of Geological Sciences, Jackson School of Geosciences, University of Texas at Austin, Austin TX USA; Planetary Geosciences Institute, Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, Knoxville TN USA; Lin, Jung-Fu [Department of Geological Sciences, Jackson School of Geosciences, University of Texas at Austin, Austin TX USA; Marshall, Edward W. [Department of Geological Sciences, Jackson School of Geosciences, University of Texas at Austin, Austin TX USA; Kono, Yoshio [HPCAT, Geophysical Laboratory, Carnegie Institution of Washington, Argonne IL USA; Gardner, James E. [Department of Geological Sciences, Jackson School of Geosciences, University of Texas at Austin, Austin TX USA

    2017-11-21

    Much of the lunar crust is monomineralic, comprising >98% plagioclase. The prevailing model argues the crust accumulated as plagioclase floated to the surface of a solidifying lunar magma ocean (LMO). Whether >98% pure anorthosites can form in a flotation scenario is debated. An important determinant of the efficiency of plagioclase fractionation is the viscosity of the LMO liquid, which was unconstrained. Here we present results from new experiments conducted on a late LMO-relevant ferrobasaltic melt. The liquid has an exceptionally low viscosity of 0.22 $+0.11\\atop{-0.19}$to 1.45 $+0.46\\atop{-0.82}$ Pa s at experimental conditions (1,300–1,600°C; 0.1–4.4 GPa) and can be modeled by an Arrhenius relation. Extrapolating to LMO-relevant temperatures, our analysis suggests a low viscosity LMO would form a stratified flotation crust, with the oldest units containing a mafic component and with very pure younger units. Old, impure crust may have been buried by lower crustal diapirs of pure anorthosite in a serial magmatism scenario.

  19. Fragments of ancient lunar crust: Ferroan noritic anorthosites from the descartes region of the Moon

    Science.gov (United States)

    Norman, M. D.; Alibert, C.; Mcculloch, M. T.

    1993-01-01

    Noritic anorthosite clasts from breccia 67016 have bulk compositions similar to that of the upper crust of the Moon and petrogenetic affinities with pristine ferroan anorthosites. Rb-Sr and Sm-Nd isotopic compositions of mineral separates from one of these clasts suggest very old (greater than or = 4.4 Ga) ages, but interpretation of these data is complicated by the multi-stage history of the clasts which involved magmatic crystallization, brecciation, subsolidus recrystallization, and sulfide metasomatism. These clasts record some of the earliest events on the Moon, including early crust formation, accretionary bombardment, and degassing of the lunar interior. Modal analyses of these clasts show they are now composed of about 70 percent plagioclase, 28 percent pyroxene, 2 percent troilite, and minor amounts of ilmenite and chromite. No metallic iron, phosphates, or other trace phases were observed. Olivine is very rare, occurring only as relicts within secondary troilite+pyroxene intergrowths which may reflect reaction of olivine with sulfurous vapors. PIXE proton microprobe analyses of the sulfides show that the metasomatism was accompanied by enrichments of Cu, Zn, Ni, Se, and Sb. The clasts have been only mildly shocked since the observed texture was established. Major and minor element mineral compositions are very homogeneous and strikingly similar to those of pristine ferroan anorthosites. Pyroxene compositions indicate equilibration temperatures of 850-900 C. Except for the sulfide and chalcophile element metasomatism, these clasts appear to be essentially monomict and probably represent a noritic member of the ferroan anorthosite suite. Their low Ni contents and Ni/Co ratios are consistent with the interpretation of these clasts as igneous rocks which have escaped mixing with meteoritic material.

  20. Scientific objectives and selection of targets for the SMART-1 Infrared Spectrometer (SIR)

    Science.gov (United States)

    Basilevsky, A. T.; Keller, H. U.; Nathues, A.; Mall, U.; Hiesinger, H.; Rosiek, M.

    2004-12-01

    The European SMART-1 mission to the Moon, primarily a testbed for innovative technologies, was launched in September 2003 and will reach the Moon in 2005. On board are several scientific instruments, including the point-spectrometer SMART-1 Infrared Spectrometer (SIR). Taking into account the capabilities of the SMART-1 mission and the SIR instrument in particular, as well as the open questions in lunar science, a selection of targets for SIR observations has been compiled. SIR can address at least five topics: (1) Surface/regolith processes; (2) Lunar volcanism; (3) Lunar crust structure; (4) Search for spectral signatures of ices at the lunar poles; and (5) Ground truth and study of geometric effects on the spectral shape. For each topic we will discuss specific observation modes, necessary to achieve our scientific goals. The majority of SIR targets will be observed in the nadir-tracking mode. More than 100 targets, which require off-nadir pointing and off-nadir tracking, are planned. It is expected that results of SIR observations will significantly increase our understanding of the Moon. Since the exact arrival date and the orbital parameters of the SMART-1 spacecraft are not known yet, a more detailed planning of the scientific observations will follow in the near future.

  1. Feldspathic Meteorites MIL 090034 and 090070: Late Additions to the Lunar Crust

    Science.gov (United States)

    Nyquist, L. E.; Shirai, N.; Yamaguchi, A.; Shih, C.-Y.; Park, J.; Ebihara, M.

    2016-01-01

    Our studies of the Miller Range lunar meteorites MIL 090034, 090036, and 090070 show them to be a diverse suite of rocks from the lunar highlands hereafter referred to as MIL 34, MIL 36, and MIL 70, resp. MIL34 and MIL70, the focus of this work, are crystalline melt breccias. Plagioclase compositions in both peak sharply around An96-97. Mg numbers of olivine vary from 58-65 with a few higher values. MIL36 is a regolith breccia. MIL 34 and MIL 70 have some of the highest Al2O3 abundances of lunar highland meteorites, indicating that they have among the largest modal abundances of plagioclase for lunar meteorites. They have lower Sc and Cr abundances than nearly all lunar highland meteorites except Dho 081, Dho 489 and Dho 733. MIL34 and MIL70 also have similar cosmic ray exposure (CRE) ages of approximately 1-2 Ma indicating they are launch paired. (MIL36 has a larger CRE age approximately greater than 70 Ma). Park et al. found a variation in Ar-Ar ages among subsamples of MIL 34 and MIL70, but preferred ages of 3500+/-110 Ma for the "Dark" phase of MIL 34 anorthite and 3520+/-30 Ma for the "Light" phase of MIL70. Bouvier et al. reported a Pb-Pb age of 3894+/-39 Ma for a feldspathic clast of MIL 34 and a similar age for a melt lithology. Here we reexamine the Rb-Sr and Sm-Nd isotopic data, which show complexities qualitatively consistent with those of the Ar-Ar and Pb-Pb data. The Sm-Nd data in particular suggest that the feldspathic compositions of MIL 34 and MIL 70 formed during initial lunar geochemical differentiation, and REE modeling suggests a relatively late-stage formation.

  2. Lava flooding of ancient planetary crusts: geometry, thickness, and volumes of flooded lunar impact basins

    International Nuclear Information System (INIS)

    Head, J.W.

    1982-01-01

    Estimates of lava volumes on planetary surfaces provide important data on the lava flooding history and thermal evolution of a planet. Lack of information concerning the configuration of the topography prior to volcanic flooding requires the use of a variety of techniques to estimate lava thicknesses and volumes. A technique is described and developed which provides volume estimates by artificially flooding unflooded lunar topography characteristic of certain geological environments, and tracking the area covered, lava thicknesses, and lava volumes. Comparisons of map patterns of incompletely buried topography in these artificially flooded areas are then made to lava-flooded topography on the Moon in order to estimate the actual lava volumes. This technique is applied to two areas related to lunar impact basins; the relatively unflooded Orientale basin, and the Archimedes-Apennine Bench region of the Imbrium basin. (Auth.)

  3. Experimental Simulations of Lunar Magma Ocean Crystallization: The Plot (But Not the Crust) Thickens

    Science.gov (United States)

    Draper, D. S.; Rapp, J. F.; Elardo, S. M.; Shearer, C. K., Jr.; Neal, C. R.

    2016-01-01

    Numerical models of differentiation of a global-scale lunar magma ocean (LMO) have raised as many questions as they have answered. Recent orbital missions and sample studies have provided new context for a large range of lithologies, from the comparatively magnesian "purest anorthosite" reported by to Si-rich domes and spinel-rich clasts with widespread areal distributions. In addition, the GRAIL mission provided strong constraints on lunar crustal density and average thickness. Can this increasingly complex geology be accounted for via the formation and evolution of the LMO? We have in recent years been conducting extensive sets of petrologic experiments designed to fully simulate LMO crystallization, which had not been attempted previously. Here we review the key results from these experiments, which show that LMO differentiation is more complex than initial models suggested. Several important features expected from LMO crystallization models have yet to be reproduced experimentally; combined modelling and experimental work by our group is ongoing.

  4. The Role of KREEP in the Production of Mg-Suite Magmas and Its Influence on the Extent of Mg-Suite Magmatism in the Lunar Crust

    Science.gov (United States)

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

    2017-01-01

    The lunar magnesian-suite, or Mg-suite, is a series of ancient plutonic rocks from the lunar crust. They have received a considerable amount of attention from lunar scientists since their discovery for three primary reasons: 1) their ages and geochemistry indicate they represent pristine magmatic samples that crystallized very soon after the formation of the Moon; 2) their ages often overlap with ages of the ferroan anorthosite (FAN) crust; and 3) planetary-scale processes are needed in formation models to account for their unique geochemical features. Taken as a whole, the Mg-suite samples, as magmatic cumulate rocks, approximate a fractional crystallization sequence in the low-pressure forsterite-anorthite-silica system, and thus these samples are generally thought to be derived from layered mafic intrusions which crystallized very slowly from magmas that intruded the anorthositic crust. However, no direct linkages have been established between different Mg-suite samples based either on field relationships or geochemistry.The model for the origin of the Mg-suite, which best fits the limited available data, is one where Mg-suite magmas form from melting of a hybrid cumulate package consisting of deep mantle dunite, crustal anorthosite, and KREEP (potassium-rare earth elements-phosphorus) at the base of the crust under the Procellarum KREEP Terrane (PKT). In this model, these three LMO (Lunar Magma Ocean) cumulate components are brought into close proximity by the cumulate overturn process. Deep mantle dunitic cumulates with an Mg number of approximately 90 rise to the base of the anorthositic crust due to their buoyancy relative to colder, more dense Fe- and Ti-rich cumulates. This hybridized source rock melts to form Mg-suite magmas, saturated in Mg-rich olivine and anorthitic plagioclase, that have a substantial KREEP component.

  5. The lunar crust - A product of heterogeneous accretion or differentiation of a homogeneous moon

    Science.gov (United States)

    Brett, R.

    1973-01-01

    The outer portion of the moon (including the aluminum-rich crust and the source regions of mare basalts) was either accreted heterogeneously or was the product of widespread differentiation of an originally homogeneous source. Existing evidence for and against each of these two models is reviewed. It is concluded that the accretionary model presents more problems than it solves, and the model involving differentiation of an originally homogeneous moon is considered to be more plausible. A hypothesis for the formation of mare basalts is advanced.

  6. Rb-Sr, Sm-Nd and Lu-Hf isotope systematics of the lunar Mg-suite: the age of the lunar crust and its relation to the time of Moon formation.

    Science.gov (United States)

    Carlson, Richard W; Borg, Lars E; Gaffney, Amy M; Boyet, Maud

    2014-09-13

    New Rb-Sr, (146,147)Sm-(142,143)Nd and Lu-Hf isotopic analyses of Mg-suite lunar crustal rocks 67667, 76335, 77215 and 78238, including an internal isochron for norite 77215, were undertaken to better define the time and duration of lunar crust formation and the history of the source materials of the Mg-suite. Isochron ages determined in this study for 77215 are: Rb-Sr=4450±270 Ma, (147)Sm-(143)Nd=4283±23 Ma and Lu-Hf=4421±68 Ma. The data define an initial (146)Sm/(144)Sm ratio of 0.00193±0.00092 corresponding to ages between 4348 and 4413 Ma depending on the half-life and initial abundance used for (146)Sm. The initial Nd and Hf isotopic compositions of all samples indicate a source region with slight enrichment in the incompatible elements in accord with previous suggestions that the Mg-suite crustal rocks contain a component of KREEP. The Sm/Nd-(142)Nd/(144)Nd correlation shown by both ferroan anorthosite and Mg-suite rocks is coincident with the trend defined by mare and KREEP basalts, the slope of which corresponds to ages between 4.35 and 4.45 Ga. These data, along with similar ages for various early Earth differentiation events, are in accord with the model of lunar formation via giant impact into Earth at ca 4.4 Ga. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  7. Global Characteristics of Porosity and Density Stratification Within the Lunar Crust from GRAIL Gravity and Lunar Orbiter Laser Altimeter Topography Data

    Science.gov (United States)

    Han, Shin-Chan; Schmerr, Nicholas; Neumann, Gregory; Holmes, Simon

    2014-01-01

    The Gravity Recovery and Interior Laboratory (GRAIL) mission is providing unprecedentedly high-resolution gravity data. The gravity signal in relation to topography decreases from 100 km to 30 km wavelength, equivalent to a uniform crustal density of 2450 kg/cu m that is 100 kg/cu m smaller than the density required at 100 km. To explain such frequency-dependent behavior, we introduce rock compaction models under lithostatic pressure that yield radially stratified porosity (and thus density) and examine the depth extent of porosity. Our modeling and analysis support the assertion that the crustal density must vary from surface to deep crust by up to 500 kg/cu m. We found that the surface density of mega regolith is around 2400 kg/cu m with an initial porosity of 10-20%, and this porosity is eliminated at 10-20 km depth due to lithostatic overburden pressure. Our stratified density models provide improved fits to both GRAIL primary and extended mission data.

  8. Sir John Meurig Thomas.

    Science.gov (United States)

    Thomas, John Meurig

    2013-10-11

    "My greatest achievement has been to combine being a teacher, a researcher, and a popularizer of science for over 50 years. My worst nightmare is to find myself dumbstruck when I am about to give a lecture …︁" This and more about Sir John Meurig Thomas can be found on page 10938. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Whither Sir William?

    Directory of Open Access Journals (Sweden)

    Stephen J. Greenberg, MSLS, PhD

    2017-04-01

    Full Text Available There are times when something is simply so familiar that we can no longer see it at all. It can be a story, or a concept, or even a flesh-and-blood person. Familiarity breeds not only contempt, but a kind of invisibility as well. For too many of us, such is the case with Sir William Osler. In his time (1849–1919, many considered him to be one of the greatest practitioners, teachers, and writers ever in the field of medicine. He was instrumental in the founding of the Medical Library Association (MLA and was elected its second president.

  10. Sir Isaac Newton

    Directory of Open Access Journals (Sweden)

    E. A. Venter

    1964-03-01

    Full Text Available Die geweldige oplewing van die Christelike wetenskaps- gedagte in ons geeslose tyd, is ongetwyfeld ’n haas onverklaar- bare verskynsel. Dwarsdeur die eeue het Christene ook wetenskap beoefen saam met ongelowiges, maar dit was eers in ons leeftyd dat die principia van die Christelike religie ook vrugbaar gemaak is vir die wetenskapsbeoefening. In hierdie verband sal die name van Dooyeweerd, Vollenhoven, Stoker e.a. steeds met eer vermeld word. Natuurlik het belydende Christene ook voorheen wel deeglik saamgewerk aan die gebou van die wetenskap. Die intieme verband tussen religie, wysbegeerte en wetenskaps­ beoefening is toe egter nog nie suiwer ingesien nie. Uit hier­ die tydperk dateer die arbeid van sir Isaac Newton.

  11. 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

  12. 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...

  13. 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.

  14. Bullialdus - Strengthening the case for lunar plutons

    Science.gov (United States)

    Pieters, Carle M.

    1991-01-01

    Although many craters expose materials of a composition different from that of the local surroundings, Bullialdus has excavated material representing three distinct stratigraphic zones that occur in the upper 6 km of crust, the top two of which are gabbroic and the deepest of which is noritic. This three-component stratigraphy at Bullialdus provides strong evidence that the lunar crust includes pockets of compositionally layered material reminiscent of mafic layered plutons. When combined with previous information on the compositional diversity at other large craters, these remote analyses obtained in a geologic context substantially strengthen the hypothesis suggested from lunar samples that plutons play an integral role in lunar crustal evolution.

  15. Sir Karl Popper and Education

    Science.gov (United States)

    McNamara, D. R.

    1978-01-01

    Sir Karl Popper is one of England's most distinguished contemporary philosophers and it is surprising that his thought has not permeated and informed educational discussion. This paper suggests that educationists have much to learn from Karl Popper's writings and explores ways in which his ideas can illuminate and advance discussion about…

  16. Geim, Prof. Sir Andre Konstantin

    Indian Academy of Sciences (India)

    Fellow Profile. Elected: 2015 Honorary. Geim, Prof. Sir Andre Konstantin FRS. Date of birth: 21 October 1958. Address: Royal Society Research Professor, University of Manchester, Oxford Road, Manchester M13 9PL, UK Contact: Office: (+44-161) 275 4120. Email: geim@manchester.ac.uk. YouTube; Twitter; Facebook ...

  17. Thomas, Prof. Sir John Meurig

    Indian Academy of Sciences (India)

    Thomas, Prof. Sir John Meurig FRS. Date of birth: 15 December 1932. Address: Department of Materials Science and, Metallurgy, New Museums Site, 27, Babbage ... Theory Of Evolution. Posted on 23 January 2018. Joint Statement by the Three Science Academies of India on the teaching of the theory of evolution more.

  18. Experimental Fractional Crystallization of the Lunar Magma Ocean

    Science.gov (United States)

    Rapp, J. F.; Draper, D. S.

    2012-01-01

    The current paradigm for lunar evolution is of crystallization of a global scale magma ocean, giving rise to the anorthositic crust and mafic cumulate interior. It is thought that all other lunar rocks have arisen from this differentiated interior. However, until recently this paradigm has remained untested experimentally. Presented here are the first experimental results of fractional crystallization of a Lunar Magma Ocean (LMO) using the Taylor Whole Moon (TWM) bulk lunar composition [1].

  19. King, Prof. Sir David Anthony

    Indian Academy of Sciences (India)

    Elected: 1998 Honorary. King, Prof. Sir David Anthony Sc.D., FRS. Date of birth: 12 August 1939. Address: Chief Scientific Adivser & Head, Office of Science and Innovation, London SW1H 0ET, U.K.. Contact: Office: (+44-020) 7215 3821. Fax: (+44-020) 7215 0314. Email: mpst.king@dti.gsi.gov.uk, dak10@cus.cam.ac.uk.

  20. REE Partitioning in Lunar Minerals

    Science.gov (United States)

    Rapp, J. F.; Lapen, T. J.; Draper, D. S.

    2015-01-01

    Rare earth elements (REE) are an extremely useful tool in modeling lunar magmatic processes. Here we present the first experimentally derived plagioclase/melt partition coefficients in lunar compositions covering the entire suite of REE. Positive europium anomalies are ubiquitous in the plagioclase-rich rocks of the lunar highlands, and complementary negative Eu anomalies are found in most lunar basalts. These features are taken as evidence of a large-scale differentiation event, with crystallization of a global-scale lunar magma ocean (LMO) resulting in a plagioclase flotation crust and a mafic lunar interior from which mare basalts were subsequently derived. However, the extent of the Eu anomaly in lunar rocks is variable. Fagan and Neal [1] reported highly anorthitic plagioclase grains in lunar impact melt rock 60635,19 that displayed negative Eu anomalies as well as the more usual positive anomalies. Indeed some grains in the sample are reported to display both positive and negative anomalies. Judging from cathodoluminescence images, these anomalies do not appear to be associated with crystal overgrowths or zones.

  1. 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

  2. Contraction or expansion of the Moon's crust during magma ocean freezing?

    Science.gov (United States)

    Elkins-Tanton, Linda T; Bercovici, David

    2014-09-13

    The lack of contraction features on the Moon has been used to argue that the Moon underwent limited secular cooling, and thus had a relatively cool initial state. A cool early state in turn limits the depth of the lunar magma ocean. Recent GRAIL gravity measurements, however, suggest that dikes were emplaced in the lower crust, requiring global lunar expansion. Starting from the magma ocean state, we show that solidification of the lunar magma ocean would most likely result in expansion of the young lunar crust, and that viscous relaxation of the crust would prevent early tectonic features of contraction or expansion from being recorded permanently. The most likely process for creating the expansion recorded by the dikes is melting during cumulate overturn of the newly solidified lunar mantle. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  3. 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.

  4. Pristine Igneous Rocks and the Genesis of Early Planetary Crusts

    Science.gov (United States)

    Warren, Paul H.; Lindstrom, David (Technical Monitor)

    2002-01-01

    Our studies are highly interdisciplinary, but are focused on the processes and products of early planetary and asteroidal differentiation, especially the genesis of the ancient lunar crust. The compositional diversity that we explore is the residue of process diversity, which has strong relevance for comparative planetology.

  5. 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.

  6. 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.

  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. 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...

  9. 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...

  10. Tectonic geomorphology of the Andes with SIR-A and SIR-B

    Science.gov (United States)

    Bloom, Arthur L.; Fielding, Eric J.

    1986-01-01

    Data takes from SIR-A and SIR-B (Shuttle Imaging Radar) crossed all of the principal geomorphic provinces of the central Andes between 17 and 34 S latitude. In conjunction with Thematic Mapping images and photographs from hand-held cameras as well as from the Large Format Camera that was flown with SIR-B, the radar images give an excellent sampling of Andean geomorphology. In particular, the radar images show new details of volcanic rocks and landforms of late Cenozoic age in the Puna, and the exhumed surfaces of tilted blocks of Precambrian crystalline basement in the Sierras Pampeanas.

  11. Biological Soil Crust Web Site

    Science.gov (United States)

    www.soilcrust.org Crust 101 Advanced Gallery References CCERS site Links Biological Soil Crusts Textbook Corrections Level of Development Index Biological soil crusts are the community of organisms , mosses, liverworts and lichens. A Field Guide to Biological Soil Crusts of Western U.S. Drylands: Common

  12. Sir Charles Scott Sherrington (1857–1952)

    Indian Academy of Sciences (India)

    Twentieth century bore witness to remarkable scientists whohave advanced our understanding of the brain. Among them,Sir Charles Scott Sherrington's ideas about the way in whichthe central nervous system operates has continuing relevanceeven today. He received honorary doctorates from twentytwouniversities and ...

  13. Sir Ronald Ross and the Malarial Parasite

    Indian Academy of Sciences (India)

    1997-08-20

    Aug 20, 1997 ... In 1857, a General in the Indian Army, Sir C C G Ross and his wife Matilda .... generally low-caste Indians who required a fee before drinking the water and ... nary demand being made upon their systems, as by fatigue, chill,.

  14. Sir Ronald Ross and the Malarial Parasite

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 7. Sir Ronald Ross and the Malarial Parasite - Discovery of its Route - From Man to Mosquito and Back. Shobhona Sharma. General Article Volume 11 Issue 7 July 2006 pp 4-13 ...

  15. Sir Charles Scott Sherrington (1857–1952)

    Indian Academy of Sciences (India)

    2016-08-26

    Aug 26, 2016 ... Twentieth century bore witness to remarkable scientists whohave advanced our understanding of the brain. Among them,Sir Charles Scott Sherrington's ideas about the way in whichthe central nervous system operates has continuing relevanceeven today. He received honorary doctorates from ...

  16. Corium crust strength measurements

    Energy Technology Data Exchange (ETDEWEB)

    Lomperski, S. [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439-4840 (United States)], E-mail: lomperski@anl.gov; Farmer, M.T. [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439-4840 (United States)], E-mail: farmer@anl.gov

    2009-11-15

    Corium strength is of interest in the context of a severe reactor accident in which molten core material melts through the reactor vessel and collects on the containment basemat. Some accident management strategies involve pouring water over the melt to solidify it and halt corium/concrete interactions. The effectiveness of this method could be influenced by the strength of the corium crust at the interface between the melt and coolant. A strong, coherent crust anchored to the containment walls could allow the yet-molten corium to fall away from the crust as it erodes the basemat, thereby thermally decoupling the melt from the coolant and sharply reducing the cooling rate. This paper presents a diverse collection of measurements of the mechanical strength of corium. The data is based on load tests of corium samples in three different contexts: (1) small blocks cut from the debris of the large-scale MACE experiments, (2) 30 cm-diameter, 75 kg ingots produced by SSWICS quench tests, and (3) high temperature crusts loaded during large-scale corium/concrete interaction (CCI) tests. In every case the corium consisted of varying proportions of UO{sub 2}, ZrO{sub 2}, and the constituents of concrete to represent a LWR melt at different stages of a molten core/concrete interaction. The collection of data was used to assess the strength and stability of an anchored, plant-scale crust. The results indicate that such a crust is likely to be too weak to support itself above the melt. It is therefore improbable that an anchored crust configuration could persist and the melt become thermally decoupled from the water layer to restrict cooling and prolong an attack of the reactor cavity concrete.

  17. Lunar Magma Ocean Crystallization: Constraints from Fractional Crystallization Experiments

    Science.gov (United States)

    Rapp, J. F.; Draper, D. S.

    2015-01-01

    The currently accepted paradigm of lunar formation is that of accretion from the ejecta of a giant impact, followed by crystallization of a global scale magma ocean. This model accounts for the formation of the anorthosite highlands crust, which is globally distributed and old, and the formation of the younger mare basalts which are derived from a source region that has experienced plagioclase extraction. Several attempts at modelling the crystallization of such a lunar magma ocean (LMO) have been made, but our ever-increasing knowledge of the lunar samples and surface have raised as many questions as these models have answered. Geodynamic models of lunar accretion suggest that shortly following accretion the bulk of the lunar mass was hot, likely at least above the solidus]. Models of LMO crystallization that assume a deep magma ocean are therefore geodynamically favorable, but they have been difficult to reconcile with a thick plagioclase-rich crust. A refractory element enriched bulk composition, a shallow magma ocean, or a combination of the two have been suggested as a way to produce enough plagioclase to account for the assumed thickness of the crust. Recently however, geophysical data from the GRAIL mission have indicated that the lunar anorthositic crust is not as thick as was initially estimated, which allows for both a deeper magma ocean and a bulk composition more similar to the terrestrial upper mantle. We report on experimental simulations of the fractional crystallization of a deep (approximately 100km) LMO with a terrestrial upper mantle-like (LPUM) bulk composition. Our experimental results will help to define the composition of the lunar crust and mantle cumulates, and allow us to consider important questions such as source regions of the mare basalts and Mg-suite, the role of mantle overturn after magma ocean crystallization and the nature of KREEP

  18. Foreword: Sir John Pendry FRS Sir John Pendry FRS

    Science.gov (United States)

    Inglesfield, John; Echenique, Pedro

    2008-07-01

    scattering is much weaker, and this allowed him to develop a method of successive approximation. The material and the calculation are cut up into a series of atomic slices, and the electronic structure solved without approximation in each slice. Being two-dimensional, this was much more manageable than a full three-dimensional calculation. Then the slices could be put together by a sort of perturbation theory to calculate the scattering current as a function of energy along each of the reciprocal lattice 'rods' allowed by the surface periodicity. John didn't just stop at having solved the problem in principle, he also developed a suite of computer codes to do the job in a routine way. He even published the code for all to use, and I believe that to the present day the calculations are still done effectively in the same way. Without the calculations, one cannot interpret the data in terms of a surface atomic structure. Effectively one is doing a computer experiment in parallel to the laboratory experiment, and one fiddles more or less systematically with the surface structure until one gets agreement between the simulations and the laboratory data. One of the things that John noticed was that the process of photoemission (UPS) from a surface is rather similar, and can be calculated in an analogous way. This suddenly became very important because the new synchrotron at Daresbury was about to become operational, pumping out billions of photons for solid state research. Sam Edwards (now Sir Sam) was head of SRC (forerunner of EPSRC) at the time and recognised the problem of interpreting all the data that the machine would provide. And after UPS would come EXAFS, and after that XANES and all the rest of the alphabet soup. With that foresight, unusual at the time, John Pendry was appointed to head the theory group at Daresbury. Previously the theoreticians had revolved around the nuclear physics accelerator, and John had to turn it completely around and refocus it, which he did

  19. 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.

  20. Sumoylation of Sir2 differentially regulates transcriptional silencing in yeast.

    Science.gov (United States)

    Hannan, Abdul; Abraham, Neethu Maria; Goyal, Siddharth; Jamir, Imlitoshi; Priyakumar, U Deva; Mishra, Krishnaveni

    2015-12-02

    Silent information regulator 2 (Sir2), the founding member of the conserved sirtuin family of NAD(+)-dependent histone deacetylase, regulates several physiological processes including genome stability, gene silencing, metabolism and life span in yeast. Within the nucleus, Sir2 is associated with telomere clusters in the nuclear periphery and rDNA in the nucleolus and regulates gene silencing at these genomic sites. How distribution of Sir2 between telomere and rDNA is regulated is not known. Here we show that Sir2 is sumoylated and this modification modulates the intra-nuclear distribution of Sir2. We identify Siz2 as the key SUMO ligase and show that multiple lysines in Sir2 are subject to this sumoylation activity. Mutating K215 alone counteracts the inhibitory effect of Siz2 on telomeric silencing. SUMO modification of Sir2 impairs interaction with Sir4 but not Net1 and, furthermore, SUMO modified Sir2 shows predominant nucleolar localization. Our findings demonstrate that sumoylation of Sir2 modulates distribution between telomeres and rDNA and this is likely to have implications for Sir2 function in other loci as well. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  1. SIR - small is safe [in reactor design

    International Nuclear Information System (INIS)

    Hayns, M.

    1989-01-01

    A joint USA-UK venture has been initiated to design a small nuclear reactor which offers low capital cost, greater flexibility and a potentially lower environmental impact. Called Safe Integral Reactor (SIR), the lead unit could be built in the United Kingdom Atomic Energy Authority's (UKAEA's) Winfrith site if the design is accepted by the UK Nuclear Installations Inspectorate (NII). This article describes the 320 MWe reactor unit that is the basis of the design being developed. (author)

  2. 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.

  3. Rare Earth Element Partitioning in Lunar Minerals: An Experimental Study

    Science.gov (United States)

    McIntosh, E. C.; Rapp, J. F.; Draper, D. S.

    2016-01-01

    The partitioning behavior of rare earth elements (REE) between minerals and melts is widely used to interpret the petrogenesis and geologic context of terrestrial and extra-terrestrial samples. REE are important tools for modelling the evolution of the lunar interior. The ubiquitous negative Eu anomaly in lunar basalts is one of the main lines of evidence to support the lunar magma ocean (LMO) hypothesis, by which the plagioclase-rich lunar highlands were formed as a flotation crust during differentiation of a global-scale magma ocean. The separation of plagioclase from the mafic cumulates is thought to be the source of the Eu depletion, as Eu is very compatible in plagioclase. Lunar basalts and volcanic glasses are commonly depleted in light REEs (LREE), and more enriched in heavy REEs (HREE). However, there is very little experimental data available on REE partitioning between lunar minerals and melts. In order to interpret the source of these distinctive REE patterns, and to model lunar petrogenetic processes, REE partition coefficients (D) between lunar minerals and melts are needed at conditions relevant to lunar processes. New data on D(sub REE) for plagioclase, and pyroxenes are now available, but there is limited available data for olivine/melt D(sub REE), particularly at pressures higher than 1 bar, and in Fe-rich and reduced compositions - all conditions relevant to the lunar mantle. Based on terrestrial data, REE are highly incompatible in olivine (i.e. D much less than 1), however olivine is the predominant mineral in the lunar interior, so it is important to understand whether it is capable of storing even small amounts of REE, and how the REEs might be fractionatied, in order to understand the trace element budget of the lunar interior. This abstract presents results from high-pressure and temperature experiments investigating REE partitioning between olivine and melt in a composition relevant to lunar magmatism.

  4. 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

  5. The mitochondrial SIR2 related protein 2 (SIR2RP2 impacts Leishmania donovani growth and infectivity.

    Directory of Open Access Journals (Sweden)

    Nimisha Mittal

    2017-05-01

    Full Text Available Leishmania donovani, a protozoan parasite is the major causative agent of visceral leishmaniasis. Increased toxicity and resistance to the existing repertoire of drugs has been reported. Hence, an urgent need exists for identifying newer drugs and drug targets. Previous reports have shown sirtuins (Silent Information Regulator from kinetoplastids as promising drug targets. Leishmania species code for three SIR2 (Silent Information Regulator related proteins. Here, we for the first time report the functional characterization of SIR2 related protein 2 (SIR2RP2 of L. donovani.Recombinant L. donovani SIR2RP2 was expressed in E. coli and purified. The enzymatic functions of SIR2RP2 were determined. The subcellular localization of LdSIR2RP2 was done by constructing C-terminal GFP-tagged full-length LdSIR2RP2. Deletion mutants of LdSIR2RP2 were generated in Leishmania by double targeted gene replacement methodology. These null mutants were tested for their proliferation, virulence, cell cycle defects, mitochondrial functioning and sensitivity to known SIR2 inhibitors.Our data suggests that LdSIR2RP2 possesses NAD+-dependent ADP-ribosyltransferase activity. However, NAD+-dependent deacetylase and desuccinylase activities were not detected. The protein localises to the mitochondrion of the promastigotes. Gene deletion studies showed that ΔLdSIR2RP2 null mutants had restrictive growth phenotype associated with accumulation of cells in the G2/M phase and compromised mitochondrial functioning. The null mutants had attenuated infectivity. Deletion of LdSIR2RP2 resulted in increased sensitivity of the parasites to the known SIR2 inhibitors. The sirtuin inhibitors inhibited the ADP-ribosyltransferase activity of recombinant LdSIR2RP2. In conclusion, sirtuins could be used as potential new drug targets for visceral leishmaniasis.

  6. 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.

  7. "Cet obscur objet du Désir"

    Directory of Open Access Journals (Sweden)

    Reto Melchior

    1996-09-01

    Full Text Available Luis Bunuel’s last film is based on Pierre Louÿs’ La Femme et le Pantin. This now forgotten bestseller, published in 1898, is drawn from Goya s painting El Pelele, in which four women are playing with a male puppet. In Pierre Louÿs’ novel this scene is inverted so that one woman with two faces plays with four men. In Cet Obscur Objet du Désir this “femme fatale” is interpreted by two actresses. The concentric structure of the film puts focus on a scene of being excluded from knowing. The technique of continually interrupting the flash-back sequences frustrates the audience because of its exclusion from the “real” course of events and gives rise to doubts whether the male protagonist tells the truth about his love-affair or whether he satisfies the curiosity of the audience by telling them Pierre Louÿs’ novel as his own story. This ambiguous art of narration mirrors Bunuel’s claim that the main topic of Cet Obscur Objet du Désir is frustration.

  8. In Situ Chemical Characterization of Mineral Phases in Lunar Granulite Meteorite Northwest Africa 5744

    Science.gov (United States)

    Kent, J. J.; Brandon, A. D.; Lapen, T. J.; Peslier, A. H.; Irving, A. J.; Coleff, D. M.

    2012-01-01

    Northwest Africa (NWA) 5744 meteorite is a granulitic and troctolitic lunar breccia which may represent nearly pristine lunar crust (Fig. 1). NWA 5744 is unusually magnesian compared to other lunar breccias, with bulk [Mg/(Mg+Fe)] 0.79 [1, 2]. Inspection shows impactor content is likely to be very minor, with low Ni content and a lack of metal grains. Some terrestrial contamination is present, evidenced by calcite within cracks. NWA 5744 has notably low concentrations of incompatible trace elements (ITEs) [2]. The goal of this study is to attempt to classify this lunar granulite through analyses of in situ phases.

  9. 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.

  10. [Sir Francis Galton: the father of eugenics].

    Science.gov (United States)

    Aubert-Marson, Dominique

    2009-01-01

    Not only was Sir Francis Galton a famous geographer and statistician, he also invented "eugenics" in 1883. Eugenics, defined as the science of improving racial stock, was developed from a new heredity theory, conceived by Galton himself, and from the evolution theory of Charles Darwin, transposed to human society by Herbert Spencer. Galton's eugenics was a program to artificially produce a better human race through regulating marriage and thus procreation. Galton put particular emphasis on "positive eugenics", aimed at encouraging the physically and mentally superior members of the population to choose partners with similar traits. In 1904, he presented his ideas in front of a vast audience of physicians and scientists in London. His widely-publicized lecture served as the starting point for the development of eugenics groups in Europe and the United States during the first half of the 20th century.

  11. 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....

  12. 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.

  13. 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.

  14. Physics of Neutron Star Crusts

    Directory of Open Access Journals (Sweden)

    Chamel Nicolas

    2008-12-01

    Full Text Available The physics of neutron star crusts is vast, involving many different research fields, from nuclear and condensed matter physics to general relativity. This review summarizes the progress, which has been achieved over the last few years, in modeling neutron star crusts, both at the microscopic and macroscopic levels. The confrontation of these theoretical models with observations is also briefly discussed.

  15. The magma ocean as an impediment to lunar plate tectonics

    Science.gov (United States)

    Warren, Paul H.

    1993-01-01

    The primary impediment to plate tectonics on the moon was probably the great thickness of its crust and particularly its high crust/lithosphere thickness ratio. This in turn can be attributed to the preponderance of low-density feldspar over all other Al-compatible phases in the lunar interior. During the magma ocean epoch, the moon's crust/lithosphere thickness ratio was at the maximum theoretical value, approximately 1, and it remained high for a long time afterwards. A few large regions of thin crust were produced by basin-scale cratering approximately contemporaneous with the demise of the magma ocean. However, these regions probably also tend to have uncommonly thin lithosphere, since they were directly heated and indirectly enriched in K, Th, and U by the same cratering process. Thus, plate tectonics on the moon in the form of systematic lithosphere subduction was impeded by the magma ocean.

  16. 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.

  17. Sir Victor Horsley: pioneer craniopharyngioma surgeon.

    Science.gov (United States)

    Pascual, José M; Prieto, Ruth; Mazzarello, Paolo

    2015-07-01

    Sir Victor Horsley (1857-1916) is considered to be the pioneer of pituitary surgery. He is known to have performed the first surgical operation on the pituitary gland in 1889, and in 1906 he stated that he had operated on 10 patients with pituitary tumors. He did not publish the details of these procedures nor did he provide evidence of the pathology of the pituitary lesions operated on. Four of the patients underwent surgery at the National Hospital for Neurology and Neurosurgery (Queen Square, London), and the records of those cases were recently retrieved and analyzed by members of the hospital staff. The remaining cases corresponded to private operations whose records were presumably kept in Horsley's personal notebooks, most of which have been lost. In this paper, the authors have investigated the only scientific monograph providing a complete account of the pituitary surgeries that Horsley performed in his private practice, La Patologia Chirurgica dell'Ipofisi (Surgical Pathology of the Hypophysis), written in 1911 by Giovanni Verga, Italian assistant professor of anatomy at the University of Pavia. They have traced the life and work of this little-known physician who contributed to the preservation of Horsley's legacy in pituitary surgery. Within Verga's pituitary treatise, a full transcription of Horsley's notes is provided for 10 pituitary cases, including the patients' clinical symptoms, surgical techniques employed, intraoperative findings, and the outcome of surgery. The descriptions of the topographical and macroscopic features of two of the lesions correspond unmistakably to the features of craniopharyngiomas, one of the squamous-papillary type and one of the adamantinomatous type. The former lesion was found on necropsy after the patient's sudden death following a temporal osteoplastic craniectomy. Surgical removal of the lesion in the latter case, with the assumed nature of an adamantinomatous craniopharyngioma, was successful. According to the

  18. Moon 101: Introducing Students to Lunar Science and Exploration

    Science.gov (United States)

    Shaner, A. J.; Shipp, S. S.; Allen, J. S.; Kring, D. A.

    2011-12-01

    Moon 101 is designed with the purpose of familiarizing students with lunar geology and exploration. Armed with guiding questions, students read articles covering various lunar science topics and browse images from past and current lunar missions to familiarize themselves with available lunar data sets. Moon 101 was originally created for high school students preparing to conduct open-inquiry, lunar research. Most high school students' knowledge of lunar science is limited to lunar phases and tides, and their knowledge of lunar exploration is close to non-existent. Moon 101 provides a summary of the state of knowledge of the Moon's formation and evolution, and the exploration that has helped inform the lunar science community. Though designed for high school students, Moon 101 is highly appropriate for the undergraduate classroom, especially at the introductory level where resources for teaching lunar science are scarce. Moon 101 is comprised of two sections covering lunar science (formation and geologic evolution of the Moon) and one section covering lunar exploration. Students read information on the formation and geologic evolution of the Moon from sources such as the Planetary Science Research Discoveries (PSRD) website and the USGS professional paper A Geologic History of the Moon by Wilhelms. While these resources are not peer-reviewed journals, the information is presented at a level more advanced than articles from newspapers and popular science magazines. This ensures that the language is accessible to students who do not have a strong lunar/planetary science background, or a strong science background in general. Formation readings include information on older and current formation hypotheses, including the Giant Impact Hypothesis, the Magma Ocean hypothesis, and the age of the lunar crust. Lunar evolution articles describe ideas such as the Late Heavy Bombardment and geologic processes such as volcanism and impact cratering. After reading the articles

  19. First measurement of 153Sm in the SIR

    International Nuclear Information System (INIS)

    Michotte, C.; Ratel, G.; Lucas, L.

    1999-01-01

    In June 1998, the NIST sent to the International Reference System (SIR) a solution of 153 Sm standardized in a 4π ionization chamber. As this radionuclide had not previously been measured in the SIR, the resulting equivalent activity A e,NIST is compared with the value calculated from the efficiency curve of the SIR. However, problems occurred owing to the presence of 154 Eu and 156 Eu impurities in the solution. The manner in which the final equivalent activity value for this solution of 153 Sm has been deduced is described in this report. (authors)

  20. 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.

  1. Sir William Mitchell (1925-2002)

    CERN Multimedia

    2002-01-01

    Sir William (Bill) Mitchell, former President of the CERN Council, died on 30th October 2002 at the age of 77. Mitchell was professor of Physics at Oxford University from 1978 to 1989, having previously been Professor of Physics, Dean of Science and Deputy Vice-Chancellor at Reading University. From 1985 to 1990 he was Chairman of the UK's Science and Engineering Research Council (SERC), which at the time was the funding agency for the UK's participation in the CERN programme. As Chairman, Mitchell was one of the UK representatives on the CERN Council, and in 1991 he was elected President, a position he held for three years. This was a difficult period for CERN. Financial problems were being faced in many member states, notably in Germany as a result of unification. This led to calls for reductions in the CERN budget and, more significantly, to requests for delays in consderation of future programmes. On the other hand for the future of CERN and the progress of elementary particle physics, it was necessary...

  2. One day, Sir, you may tax it

    CERN Multimedia

    2011-01-01

    “One day, Sir, you may tax it”… Those are the words I used to get the audience's attention during my talk at the World Economic Forum’s annual meeting in Davos, where I was invited to speak about the science agenda in 2011. For those of you who don’t know the quote, it was Michael Faraday’s response to William Gladstone when asked to comment on the utility of his blue-sky research into the newfangled phenomenon of electricity.   So what does a 19th century English scientist have to do with the science agenda today? A great deal, I would contend. Faraday was doing basic science, but he had the foresight to realise that through applied research his findings could one day be developed into something taxable – as it turned out, electric light. Faraday had a sense of the potential of his blue-sky research, but he also appreciated that basic science alone is not enough. This was my key message in Davos. Governments often speak of ...

  3. Lunar impact basins and crustal heterogeneity: New western limb and far side data from galileo

    Science.gov (United States)

    Belton, M.J.S.; Head, J. W.; Pieters, C.M.; Greeley, R.; McEwen, A.S.; Neukum, G.; Klaasen, K.P.; Anger, C.D.; Carr, M.H.; Chapman, C.R.; Davies, M.E.; Fanale, F.P.; Gierasch, P.J.; Greenberg, R.; Ingersoll, A.P.; Johnson, T.; Paczkowski, B.; Pilcher, C.B.; Veverka, J.

    1992-01-01

    Multispectral images of the lunar western limb and far side obtained from Galileo reveal the compositional nature of several prominent lunar features and provide new information on lunar evolution. The data reveal that the ejecta from the Orientale impact basin (900 kilometers in diameter) lying outside the Cordillera Mountains was excavated from the crust, not the mantle, and covers pre-Orientale terrain that consisted of both highland materials and relatively large expanses of ancient mare basalts. The inside of the far side South Pole-Aitken basin (>2000 kilometers in diameter) has low albedo, red color, and a relatively high abundance of iron- and magnesium-rich materials. These features suggest that the impact may have penetrated into the deep crust or lunar mantle or that the basin contains ancient mare basalts that were later covered by highlands ejecta.

  4. 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.

  5. Sir Robert Sidney’s Poems Revisited: the alternative sequence

    OpenAIRE

    Relvas, Maria de Jesus C.

    1997-01-01

    The essay approaches the lyric sequence written by Sir Robert Sidney (1563-1626) in the Elizabethan age, by mainly exploring its unique formal structure, which encloses an alternative sequence formed by a re-numbering of several poems.

  6. Validation of the Spanish SIRS with monolingual Hispanic outpatients.

    Science.gov (United States)

    Correa, Amor A; Rogers, Richard; Hoersting, Raquel

    2010-09-01

    Psychologists are faced with formidable challenges in making their assessment methods relevant to growing numbers of Hispanic clients for whom English is not the primary or preferred language. Among other clinical issues, the determination of malingering has profound consequences for clients. In this investigation, we evaluated a Spanish translation of the Structured Interview of Reported Symptoms (SIRS; Rogers, Bagby, & Dickens, 1992) with 80 Spanish-speaking Hispanic American outpatients. Using a between-subjects simulation design, the Spanish SIRS was found to produce reliable results with small standard errors of measurement. Regarding validity, very large effect sizes (mean Cohen's d= 2.00) were observed between feigners and honest responders for the SIRS primary scales. We consider the potential role of the Spanish SIRS with reference to Spanish translations for other assessment instruments.

  7. Development of Immunopathobiogenesis on SIRS-Sepsis

    Directory of Open Access Journals (Sweden)

    A Guntur Hermawan

    2009-04-01

    Full Text Available Over the past decade, sepsis has been diagnosed according to consensus guidelines established in 1991 as an infection in addition to the symptoms of systemic inflammatory response syndrome (SIRS. In addition to the previous criteria, the 2001 conference added several new diagnostic criteria for sepsis. Of particular interest was the inclusion of the biomarkers procalcitonin (PCT and C-reactive protein (CRP, despite the overall conclusion that it was premature to use biomarkers for sepsis diagnosis. The primary recommendation of the panel was the implementation of the Predisposition, insult Infection, Response, and Organ dysfunction (PIRO.The immune system has traditionally been devided into innate and adaptive components, each of which has a different role and function in defending the host against infectious agents. Stimulation of different TLRs induces distinct patterns of gene expression, which not only leads to the activation of innate immunity but also increasing evidence supports an additional critical role for TLRs in orchestrating the development of adaptive immune responses. The superantigens are able to induce toxic shock syndrome and can sometimes cause multiple organ failure via adaptive immune system. The superantigenic activity of the bacterial exotoxins can be attributed to their ability to cross-link major histocompatibility complex class II molecules on antigen-presenting cells outside the peptide groove with T-cell receptors to form a trimolecular complex. This trimolecular interaction leads to uncontrolled release of a number of proinflammatory cytokines. Proinflammatory cytokines especially IFN-γ and TNF-α, the key cytokines causing toxic shock syndrome. KEYWORDS: sepsis, innate immunity, adaptive.

  8. 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

  9. Automated Endmember Selection for Nonlinear Unmixing of Lunar Spectra

    Science.gov (United States)

    Felder, M. P.; Grumpe, A.; Wöhler, C.; Mall, U.

    2013-09-01

    An important aspect of the analysis of remotely sensed lunar reflectance spectra is their decomposition into intimately mixed constituents. While some methods rely on unmixing of the observed reflectance spectra [1] or on the identification of minerals by extracting the depths and positions of mineral-specific absorption troughs [2, 3], these approaches do not allow for an automated selection of the (a priori unknown) endmembers from a large set of possible constituents. In this study, a non-linear spectral unmixing approach combined with an automated endmember selection scheme is proposed. This method is applied to reflectance spectra of the SIR-2 point spectrometer [4] carried by the Chandrayaan-1 spacecraft.

  10. Collisional stripping of planetary crusts

    Science.gov (United States)

    Carter, Philip J.; Leinhardt, Zoë M.; Elliott, Tim; Stewart, Sarah T.; Walter, Michael J.

    2018-02-01

    Geochemical studies of planetary accretion and evolution have invoked various degrees of collisional erosion to explain differences in bulk composition between planets and chondrites. Here we undertake a full, dynamical evaluation of 'crustal stripping' during accretion and its key geochemical consequences. Crusts are expected to contain a significant fraction of planetary budgets of incompatible elements, which include the major heat producing nuclides. We present smoothed particle hydrodynamics simulations of collisions between differentiated rocky planetesimals and planetary embryos. We find that the crust is preferentially lost relative to the mantle during impacts, and we have developed a scaling law based on these simulations that approximates the mass of crust that remains in the largest remnant. Using this scaling law and a recent set of N-body simulations of terrestrial planet formation, we have estimated the maximum effect of crustal stripping on incompatible element abundances during the accretion of planetary embryos. We find that on average approximately one third of the initial crust is stripped from embryos as they accrete, which leads to a reduction of ∼20% in the budgets of the heat producing elements if the stripped crust does not reaccrete. Erosion of crusts can lead to non-chondritic ratios of incompatible elements, but the magnitude of this effect depends sensitively on the details of the crust-forming melting process on the planetesimals. The Lu/Hf system is fractionated for a wide range of crustal formation scenarios. Using eucrites (the products of planetesimal silicate melting, thought to represent the crust of Vesta) as a guide to the Lu/Hf of planetesimal crust partially lost during accretion, we predict the Earth could evolve to a superchondritic 176Hf/177Hf (3-5 parts per ten thousand) at present day. Such values are in keeping with compositional estimates of the bulk Earth. Stripping of planetary crusts during accretion can lead to

  11. 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.

  12. 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.

  13. 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. .

  14. Lymphocyte integrin expression differences between SIRS and sepsis patients.

    Science.gov (United States)

    Heffernan, D S; Monaghan, S F; Ayala, Alfred

    2017-11-01

    Systemic Inflammatory Response Syndrome (SIRS) and sepsis remain leading causes of death. Despite many similarities, the two entities are very distinct clinically and immunologically. T-Lymphocytes play a key pivotal role in the pathogenesis and ultimately outcome following both SIRS and sepsis. Integrins are essential in the trafficking and migration of lymphocytes. They also serve vital roles in efficient wound healing and clearance of infections. Here, we investigate whether integrin expression, specifically β1 (CD29) and β2 (CD18), are disrupted in SIRS and sepsis, and assess differences in integrin expression between these two critically ill clinical categories. T-Lymphocytes were isolated from whole blood collected from ICU patients exhibiting SIRS or sepsis. Samples were analyzed for CD18 (β2) and CD29 (β1) on CD3 + T cells through flow cytometry. Septic patients were stratified into either exclusively abdominal or non-abdominal sources of sepsis. CD18 was almost ubiquitously expressed on CD3 + T cells irrespective of clinical condition. However, CD29 (β1 integrin) was lowest in SIRS patients (20.4% of CD3 + T cells) when compared with either septic patients (35.5%) or healthy volunteers (54.1%). Furthermore, there was evidence of compartmentalization in septic patients, where abdominal sources had a greater percentage of CD3 + CD29 + T cells (41.7%) when compared with those with non-abdominal sources (29.5%). Distinct differences in T-cell integrin expression exists between patients in SIRS versus sepsis, as well as relative to the source of sepsis. Further work is needed to understand cause and effect relative to the progression from SIRS into sepsis.

  15. 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

  16. Palaeomagnetism and the continental crust

    Energy Technology Data Exchange (ETDEWEB)

    Piper, J.D.A.

    1987-01-01

    This book is an introduction to palaeomagnetism offering treatment of theory and practice. It analyzes the palaeomagnetic record over the whole of geological time, from the Archaean to the Cenozoic, and goes on to examine the impact of past geometries and movements of the continental crust at each geological stage. Topics covered include theory of rock and mineral magnetism, field and laboratory methods, growth and consolidation of the continental crust in Archaean and Proterozoic times, Palaeozoic palaeomagnetism and the formation of Pangaea, the geomagnetic fields, continental movements, configurations and mantle convection.

  17. 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 ...

  18. 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.

  19. SIR-2 Data Normalization and Integration with M3 Data

    Science.gov (United States)

    Grumpe, A.; Felder, M. P.; Wöhler, C.; Mall, U.

    2013-09-01

    The point spectrometer SIR-2 on Chandrayaan-1 provided radiance spectra integrated over circular footprints of 200 m diameter in the wavelength range 934-2410.8 nm in 256 channels [1]. To analyze SIR-2 reflectance spectra in their spatial context, a coregistration to Chandrayaan-1 M³ hyperspectral images [2] as well as a correction for topography and thermal emission are inevitable. The thermal and topographic correction procedure is based on the surface temperature and a digital elevation model (DEM) inferred from M³ data. The corrected reflectance spectra are then normalized to a standard illumination and viewing geometry.

  20. Statistics of Magnetar Crusts Magnetoemission

    Directory of Open Access Journals (Sweden)

    Kondratyev V. N.

    2016-01-01

    Full Text Available Soft repeating gamma-ray (SGR bursts are considered as magnetoemission of crusts of magnetars (ultranamagnetized neutron stars. It is shown that all the SGR burst observations can be described and systematized within randomly jumping interacting moments model including quantum fluctuations and internuclear magnetic interaction in an inhomogeneous crusty nuclear matter.

  1. Hyper-Spectral Imager in visible and near-infrared band for lunar ...

    Indian Academy of Sciences (India)

    India's first lunar mission, Chandrayaan-1, will have a Hyper-Spectral Imager in the visible and near-infrared spectral ... mapping of the Moon's crust in a large number of spectral channels. The planned .... In-flight verification may be done.

  2. 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

  3. 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.

  4. 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.

  5. On the Shoulders of Sir Isaac Newton and Arthur Storer

    Science.gov (United States)

    Martin, Helen E.; Evans-Gondo, Bonita

    2013-01-01

    Helen E. Martin, the author of this article, is a retired National Board Certified Teacher who has been researching Sir Isaac Newton's unpublished manuscripts for over three decades. While researching the work of Newton, a teacher she was mentoring asked for some hands-on activities to study planetary motion. The description of the activity…

  6. Sir William Jenner (1815-1898) and Queen Victoria.

    Science.gov (United States)

    Seddon, David; Queen Victoria

    2004-08-01

    This biographical note outlines the work of Sir William Jenner (1815-1898), court physician 1861-93 and President of the Royal College of Physicians 1881-8. He was the first to distinguish between typhoid and typhus both clinically and pathologically.

  7. Investigating The Travelling Wave Solution For an SIR Endemic ...

    African Journals Online (AJOL)

    This paper presents the travelling wave solution for an SIR endemic disease model with no disease related death when the spatial spread of the susceptible is not negligible. In this case the disease is driven by both the susceptible and the infective classes. The population is open since the disease is habitually prevalent in ...

  8. Buffels (Wes), Elsies, Sir Lowry's pass, Steenbras and Buffels (Oos)

    CSIR Research Space (South Africa)

    Heinecken, TJE

    1982-06-01

    Full Text Available This report is a synthesis of all available information on five of the smaller rivers discharging in to False bay combined as a single volume. The rivers dealt with are the Buffels (Wes), Elsies, Sir Lowry' Pass, Steenbras and Buffels (Oos). False...

  9. Sir John and Lady Rita Cornforth: a distinguished chemical partnership.

    Science.gov (United States)

    Purchase, Rupert; Hanson, James R

    2015-01-01

    This review describes the life of Sir John Cornforth AC CBE FRS, who was awarded the Nobel Prize for Chemistry in 1975. It covers his early life in Australia, his work in Oxford, the National Institute for Medical Research, the Milstead Laboratory of Chemical Enzymology and the University of Sussex, together with the contributions made by his wife, Lady Rita Cornforth.

  10. Science and controversy a biography of Sir Norman Lockyer

    CERN Document Server

    Meadows, A

    2008-01-01

    Sir Norman Lockyer left Nature, the world''s leading scientific journal, as his lasting memorial. But his life, and controversial theories, are an important part of science history. His ideas were at the forefront of public debate, and ranged from brilliant to perverse. This entertaining book is a fascinating insight into his eventful life

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

    Science.gov (United States)

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

    2015-12-01

    Fragmentation and overturn of lunar surface materials produces a layer of regolith, which increases in thickness through time. Experiments on the lunar surface during the Apollo era, combined with remote sensing, found that the upper 10's of cm of regolith exhibit a rapid increase in density and thermal conductivity with depth. This is interpreted to be the signature of impact gardening, which operates most rapidly in the uppermost layers. Gravity data from the GRAIL mission showed that impacts have also extensively fractured the deeper crust. The breakdown and mixing of crustal materials is therefore a central process to lunar evolution and must be understood in order to interpret compositional information from remote sensing and sample analysis. Recently, thermal infrared data from the Lunar Reconnaissance Orbiter (LRO) Diviner radiometer were used to provide the first remote observational constraints on the rate of ejecta breakdown around craters L., Campbell, B. A., Allen, C. C., Carter, L. M., & Paige, D. A. (2014). Constraints on the recent rate of lunar ejecta breakdown and implications for crater ages. Geology, 42(12), 1059-1062.

  12. The Lunar Magma Ocean: Sharpening the Focus on Process and Composition

    Science.gov (United States)

    Rapp, J. F.; Draper, D. S.

    2014-01-01

    The currently accepted model for the formation of the lunar anorthositic crust is by flotation from a crystallizing lunar magma ocean (LMO) shortly following lunar accretion. Anorthositic crust is globally distributed and old, whereas the mare basalts are younger and derived from a source region that has experienced plagioclase extraction. Several attempts at modelling such a crystallization sequence have been made [e.g. 1, 2], but our ever-increasing knowledge of the lunar samples and surface have raised as many questions as these models have answered. This abstract presents results from our ongoing ex-periments simulating LMO crystallization and address-ing a range of variables. We investigate two bulk com-positions, which span most of the range of suggested lunar bulk compositions, from the refractory element enriched Taylor Whole Moon (TWM) [3] to the more Earth-like Lunar Primitive Upper Mantle (LPUM) [4]. We also investigate two potential crystallization mod-els: Fully fractional, where crystallizing phases are separated from the magma as they form and sink (or float in the case of plagioclase) throughout magma ocean solidification; and a two-step process suggested by [1, 5] with an initial stage of equilibrium crystalliza-tion, where crystals remain entrained in the magma before the crystal burden increases viscosity enough that convection slows and the crystals settle, followed by fractional crystallization. Here we consider the frac-tional crystallization part of this process; the equilibri-um cumulates having been determined by [6].

  13. Physics of the earth crust

    International Nuclear Information System (INIS)

    Lauterbach, R.

    1977-01-01

    This book deals in 12 chapters, amongst other things, with the subjects: Structure of the crust and the upper earth mantle, geology and geophysics of sea beds, satellite and aero-methods of geophysics, state of the art of geothermal research, geophysical potential fields and their anomalies, applied seismology, electrical methods of geophysics, geophysics in engineering and rock engineering, borehole geophysics, petrophysics, and geochemistry. (RW) [de

  14. 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...

  15. 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...

  16. 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.

  17. 33 CFR 147.817 - Sir Douglas Morpeth Tension Leg Platform safety zone.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Sir Douglas Morpeth Tension Leg... HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.817 Sir Douglas Morpeth Tension Leg Platform safety zone. (a) Description. The Sir Douglas Morpeth Tension Leg Platform (Morpeth...

  18. 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.

  19. 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.

  20. Regulating repression: roles for the sir4 N-terminus in linker DNA protection and stabilization of epigenetic states.

    Directory of Open Access Journals (Sweden)

    Stephanie Kueng

    Full Text Available Silent information regulator proteins Sir2, Sir3, and Sir4 form a heterotrimeric complex that represses transcription at subtelomeric regions and homothallic mating type (HM loci in budding yeast. We have performed a detailed biochemical and genetic analysis of the largest Sir protein, Sir4. The N-terminal half of Sir4 is dispensable for SIR-mediated repression of HM loci in vivo, except in strains that lack Yku70 or have weak silencer elements. For HM silencing in these cells, the C-terminal domain (Sir4C, residues 747-1,358 must be complemented with an N-terminal domain (Sir4N; residues 1-270, expressed either independently or as a fusion with Sir4C. Nonetheless, recombinant Sir4C can form a complex with Sir2 and Sir3 in vitro, is catalytically active, and has sedimentation properties similar to a full-length Sir4-containing SIR complex. Sir4C-containing SIR complexes bind nucleosomal arrays and protect linker DNA from nucleolytic digestion, but less effectively than wild-type SIR complexes. Consistently, full-length Sir4 is required for the complete repression of subtelomeric genes. Supporting the notion that the Sir4 N-terminus is a regulatory domain, we find it extensively phosphorylated on cyclin-dependent kinase consensus sites, some being hyperphosphorylated during mitosis. Mutation of two major phosphoacceptor sites (S63 and S84 derepresses natural subtelomeric genes when combined with a serendipitous mutation (P2A, which alone can enhance the stability of either the repressed or active state. The triple mutation confers resistance to rapamycin-induced stress and a loss of subtelomeric repression. We conclude that the Sir4 N-terminus plays two roles in SIR-mediated silencing: it contributes to epigenetic repression by stabilizing the SIR-mediated protection of linker DNA; and, as a target of phosphorylation, it can destabilize silencing in a regulated manner.

  1. 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

  2. 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

  3. Sir Karl Popper and his philosophy of physics

    Science.gov (United States)

    Jammer, Max

    1991-12-01

    The eminent mathematical physicist Sir Hermann Bondi once said: “There is no more to science than its method, and there is no more to its method than Popper has said.” Indeed, many regard Sir Karl Raimund Popper the greatest philosopher of science in our generation. Much of what Popper “has said” refers to physics, but physicists, generally speaking, have little knowledge of what he has said. True, Popper's philosophy of science and, in particular, his realistic interpretation of quantum mechanics deviates considerably from the generally accepted doctrine. But as Popper, rightly I think, points out, it is precisely the proliferation of divergent theories which promotes the growth of scientific knowledge; it would be a danger for physics if physicists were dogmatically tied to a single theory or would not test their theory against alternatives. It is for this purpose that, on the occasion of the nonagenarian celebration of Popper's birthday, the present essay has been written.

  4. The susceptible-infected-recovered (SIR) model for viral marketing

    Science.gov (United States)

    Ismail, Siti Suhaila; Akil, Ku Azlina Ku; Chulan, Majdah; Sharif, Noorzila

    2017-11-01

    Viral marketing is a marketing strategy utilizes social media to spread information about a product or services provided. It is the most powerful way to share information in a short amount of time. The objective of this study is to investigate the dynamic of viral marketing within a time duration in the point of view of mathematics. This study used the epidemiological model known as Susceptible-Infected-Recovered (SIR). The model consists of a system of three differential equations with three state variables namely susceptible (S), infected (I) and recovered (R). It considers a case of SIR model with demography. Numerical experiments have been performed. The results show that viral marketing reaches its peak within two days. The online messages shared will become higher if the initial number of the infected individual has been increased.

  5. Stability analysis of the Euler discretization for SIR epidemic model

    International Nuclear Information System (INIS)

    Suryanto, Agus

    2014-01-01

    In this paper we consider a discrete SIR epidemic model obtained by the Euler method. For that discrete model, existence of disease free equilibrium and endemic equilibrium is established. Sufficient conditions on the local asymptotical stability of both disease free equilibrium and endemic equilibrium are also derived. It is found that the local asymptotical stability of the existing equilibrium is achieved only for a small time step size h. If h is further increased and passes the critical value, then both equilibriums will lose their stability. Our numerical simulations show that a complex dynamical behavior such as bifurcation or chaos phenomenon will appear for relatively large h. Both analytical and numerical results show that the discrete SIR model has a richer dynamical behavior than its continuous counterpart

  6. The Systemic Inflammatory Response Syndrome (SIRS in acutely hospitalised medical patients: a cohort study

    Directory of Open Access Journals (Sweden)

    Storgaard Merete

    2009-12-01

    Full Text Available Abstract Background Sepsis is an infection which has evoked a systemic inflammatory response. Clinically, the Systemic Inflammatory Response Syndrome (SIRS is identified by two or more symptoms including fever or hypothermia, tachycardia, tachypnoea and change in blood leucocyte count. The relationship between SIRS symptoms and morbidity and mortality in medical emergency ward patients is unknown. Methods We conducted a prospective cohort study of the frequency of SIRS and its relationship to sepsis and death among acutely hospitalised medical patients. In 437 consecutive patients, SIRS status, blood pressure, infection and comorbidity on admission was registered together with 28-day mortality. Results A hundred and fifty-four patients (35% had SIRS on admission, 211 patients (48% had no SIRS, and 72 patients (16% had insufficient data to evaluate their SIRS status. SIRS patients were 2.2 times more frequently infected, with 66/154 SIRS patients versus 41/211 non-SIRS patients: p Conclusion We found SIRS status on admission to be moderately associated with infection and strongly related to 28-day mortality.

  7. LROC Advances in Lunar Science

    Science.gov (United States)

    Robinson, M. S.

    2012-12-01

    Since entering orbit in 2009 the Lunar Reconnaissance Orbiter Camera (LROC) has acquired over 700,000 Wide Angle Camera (WAC) and Narrow Angle Camera (NAC) images of the Moon. This new image collection is fueling research into the origin and evolution of the Moon. NAC images revealed a volcanic complex 35 x 25 km (60N, 100E), between Compton and Belkovich craters (CB). The CB terrain sports volcanic domes and irregular depressed areas (caldera-like collapses). The volcanic complex corresponds to an area of high-silica content (Diviner) and high Th (Lunar Prospector). A low density of impact craters on the CB complex indicates a relatively young age. The LROC team mapped over 150 volcanic domes and 90 volcanic cones in the Marius Hills (MH), many of which were not previously identified. Morphology and compositional estimates (Diviner) indicate that MH domes are silica poor, and are products of low-effusion mare lavas. Impact melt deposits are observed with Copernican impact craters (>10 km) on exterior ejecta, the rim, inner wall, and crater floors. Preserved impact melt flow deposits are observed around small craters (25 km diam.), and estimated melt volumes exceed predictions. At these diameters the amount of melt predicted is small, and melt that is produced is expected to be ejected from the crater. However, we observe well-defined impact melt deposits on the floor of highland craters down to 200 m diameter. A globally distributed population of previously undetected contractional structures were discovered. Their crisp appearance and associated impact crater populations show that they are young landforms (features place bounds on the amount of global radial contraction and the level of compressional stress in the crust. WAC temporal coverage of the poles allowed quantification of highly illuminated regions, including one site that remains lit for 94% of a year (longest eclipse period of 43 hours). Targeted NAC images provide higher resolution characterization of

  8. 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.

  9. 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.

  10. SirT1 regulates energy metabolism and response to caloric restriction in mice.

    Directory of Open Access Journals (Sweden)

    Gino Boily

    Full Text Available The yeast sir2 gene and its orthologues in Drosophila and C. elegans have well-established roles in lifespan determination and response to caloric restriction. We have studied mice carrying two null alleles for SirT1, the mammalian orthologue of sir2, and found that these animals inefficiently utilize ingested food. These mice are hypermetabolic, contain inefficient liver mitochondria, and have elevated rates of lipid oxidation. When challenged with a 40% reduction in caloric intake, normal mice maintained their metabolic rate and increased their physical activity while the metabolic rate of SirT1-null mice dropped and their activity did not increase. Moreover, CR did not extend lifespan of SirT1-null mice. Thus, SirT1 is an important regulator of energy metabolism and, like its orthologues from simpler eukaryotes, the SirT1 protein appears to be required for a normal response to caloric restriction.

  11. Stability and bifurcation analysis in a delayed SIR model

    International Nuclear Information System (INIS)

    Jiang Zhichao; Wei Junjie

    2008-01-01

    In this paper, a time-delayed SIR model with a nonlinear incidence rate is considered. The existence of Hopf bifurcations at the endemic equilibrium is established by analyzing the distribution of the characteristic values. A explicit algorithm for determining the direction of the Hopf bifurcation and the stability of the bifurcating periodic solutions are derived by using the normal form and the center manifold theory. Numerical simulations to support the analytical conclusions are carried out

  12. [Sir Harold Ridley--the creator of modern cataract surgery].

    Science.gov (United States)

    Obuchowska, Iwona; Mariak, Zofia

    2005-01-01

    In February 2000, the worldwide ophthalmology community celebrated the 50th anniversary of one of the twentieth century's most important innovations in eye care--the implantation of the first intraocular lens after cataract extraction by Sir Harold Ridley. It was the initiation of a golden age for the development of ophthalmology, especially cataract surgery. In our paper we would like to remember this outstanding English ophthalmologist and his great invention.

  13. Development of SIR-C Ground Calibration Equipment

    Science.gov (United States)

    Freeman, A.; Azeem, M.; Haub, D.; Sarabandi, K.

    1993-01-01

    SIR-C/X-SAR is currently scheduled for launch in April 1994. SIR-C is an L-Band and C-Band, multi-polarization spaceborne SAR system developed by NASA/JPL. X- SAR is an X-Band SAR system developed by DARA/ASI. One of the problems involved in calibrating the SIR-C instrument is to make sure that the horizontal (H) and vertical (V) polarized beams are aligned in the azimuth direction, i.e.. that they are pointing in the same direction. This is important if the polarimetric performance specifications for the system are to be met. To solve this problem, we have designed and built a prototype of a low-cost ground receiver capable of recording received power from two antennas, one H-polarized, the other V-polarized. The two signals are mixed to audio then recorded on the left and right stereo channels of a standard audio cassette player. The audio cassette recording can then be played back directly into a Macintosh computer, where it is digitized. Analysis of.

  14. 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.

  15. 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.

  16. Investigation of lunar crustal structure and isostasy. Final technical report

    International Nuclear Information System (INIS)

    Thurber, C.H.

    1987-07-01

    The lunar mascon basins have strongly free air gravity anomalies, generally exceeding 100 milligals at an elevation of 100 km. The source of the anomalies is a combination of mantle uplift beneath the impact basins and subsequent infilling by high-density mare basalts. The relative contribution of these two components is still somewhat uncertain, although it is generally accepted that the amount of mantle uplift greatly exceeds the thickness of the basalts. Extensive studies have been carried out of the crustal structure of mare basins, based on gravity data, and their tectonic evolution, based on compressive and extensional tectonic features. The present study endeavored to develop a unified, self-consistent model of the lunar crust and lithosphere incorporating both gravity and tectonic constraints

  17. 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.

  18. 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.

  19. 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

  20. 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.)

  1. 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.

  2. 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

  3. 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

  4. An SIRS model with a nonlinear incidence rate

    International Nuclear Information System (INIS)

    Jin Yu; Wang, Wendi; Xiao Shiwu

    2007-01-01

    The global dynamics of an SIRS model with a nonlinear incidence rate is investigated. We establish a threshold for a disease to be extinct or endemic, analyze the existence and asymptotic stability of equilibria, and verify the existence of bistable states, i.e., a stable disease free equilibrium and a stable endemic equilibrium or a stable limit cycle. In particular, we find that the model admits stability switches as a parameter changes. We also investigate the backward bifurcation, the Hopf bifurcation and Bogdanov-Takens bifurcation and obtain the Hopf bifurcation criteria and Bogdanov-Takens bifurcation curves, which are important for making strategies for controlling a disease

  5. Sir Winston Churchill: treatment for pneumonia in 1943 and 1944.

    Science.gov (United States)

    Vale, J A; Scadding, J W

    2017-12-01

    This paper reviews Churchill's illnesses in February 1943 and August/September 1944 when he developed pneumonia; on the first occasion this followed a cold and sore throat. Churchill was managed at home by Sir Charles Wilson (later Lord Moran) with the assistance of two nurses and the expert advice of Dr Geoffrey Marshall, Brigadier Lionel Whitby and Colonel Robert Drew. A sulphonamide (sulphathiazole on the first occasion) was prescribed for both illnesses. Churchill recovered, and despite his illnesses continued to direct the affairs of State from his bed. On the second occasion, Churchill's illness was not made public.

  6. Sir Rudolf Peierls Selected private and scientific correspondence

    CERN Document Server

    Lee, Sabine

    2007-01-01

    This edition of the private and scientific correspondence of Sir Rudolf Peierls gives a unique insight into the life and work of one of the greatest theoretical physicists of the 20th century. Rudolf Peierls' scientific work contributed to the early developments in quantum mechanics, and he is well known and much appreciated for his contributions to various disciplines, including solid state physics, nuclear physics, and particle physics. As an enthusiastic and devoted teacher, he passed on his knowledge and understanding and inspired the work of collaborators and students alike. As an effecti

  7. Sir Ronald A. Fisher and the International Biometric Society.

    Science.gov (United States)

    Billard, Lynne

    2014-06-01

    The year 2012 marks the 50th anniversary of the death of Sir Ronald A. Fisher, one of the two Fathers of Statistics and a Founder of the International Biometric Society (the "Society"). To celebrate the extraordinary genius of Fisher and the far-sighted vision of Fisher and Chester Bliss in organizing and promoting the formation of the Society, this article looks at the origins and growth of the Society, some of the key players and events, and especially the roles played by Fisher himself as the First President. A fresh look at Fisher, the man rather than the scientific genius is also presented. © 2014, The International Biometric Society.

  8. 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

  9. Effect of thicker oceanic crust in the Archaean on the growth of continental crust through time

    International Nuclear Information System (INIS)

    Wilks, M.E.

    1988-01-01

    Present crustal evolution models fail to account for the generation of the large volume of continental crust in the required time intervals. All Archaean plate tectonic models, whether invoking faster spreading rates, similar to today's spreading rates, or longer ridge lengths, essentially propose that continental crust has grown by island arc accretion due to the subduction of oceanic crust. The petrological differences that characterize the Archaean from later terrains result from the subduction of hotter oceanic crust into a hotter mantle. If the oceanic crust was appreciably thicker in the Archaean, as geothermal models would indicate, this thicker crust is surely going to have an effect on tectonic processes. A more valid approach is to compare the possible styles of convergence of thick oceanic crust with modern convergence zones. The best modern analog occurs where thick continental crust is colliding with thick continental crust. Oceanic crustal collision on the scale of the present-day Himalayan continental collision zone may have been a frequent occurrence in the Archaean, resulting in extensive partial melting of the hydrous underthrust oceanic crust to produce voluminous tonalite melts, leaving a depleted stabilized basic residuum. Present-day island arc accretion may not have been the dominant mechanism for the growth of the early Archaean crust

  10. SIR-ZEE: plataforma tecnológica para el desarrollo local SIR-ZEE: technology platform for local development

    Directory of Open Access Journals (Sweden)

    Marlen Treviño Villalobos

    2012-11-01

    Full Text Available El Sistema de Información Regional de la Zona Económica Especial (SIR-ZEE nació en Costa Rica aproximadamente en 1998, cuando se concibió la idea de crear un sistema informático para recopilar, gestionar y ofrecer temáticas generadas en forma digital por diferentes entidades públicas y privadas. En el 2008, con los fondos del Programa de Regionalización Interuniversitaria del Consejo Nacional de Rectores, se aprobó la iniciativa SIR-ZEE, Plataforma Tecnológica para el Desarrollo Local, que buscó fortalecer las capacidades productivas y las capacidades de gobernabilidad en la Región Huetar Norte mediante el acceso a la información oportuna y relevante para el desarrollo económico local. Este artículo tiene como objetivo mostrar no solo la relevancia de un sistema de información en la planificación del desarrollo local, sino también que, en la actualidad, el SIR-ZEE se está convirtiendo en una ventaja competitiva para la Región Huetar Norte, ya que facilita el proceso de toma decisiones. Los principales resultados obtenidos al final de la iniciativa fueron una propuesta metodológica para la elaboración de planes estratégicos de desarrollo local en la Región Huetar Norte, la sensibilización de los actores locales sobre la participación ciudadana en las diferentes fases de la planificación, un diagnóstico territorial con el valor agregado de contar con la información georreferenciada y disponible en un sitio web, y avances en la elaboración del Plan estratégico de desarrollo local.The Regional Information System of the Special Economic Zone (SIR-ZEE was born about the year 1998 as a computer system to collect, manage and offer thematic generated in digital format by different public and private entities. In 2008, with the funds of Interuniversity Regionalization Program the National Council of Rectors approved the initiative SIR- ZEE: Platform Technology for Local Development which sought to strengthen productive

  11. A Novel Method of SIR Measurement for Power Control in CDMA Systems

    International Nuclear Information System (INIS)

    Yu, J; Wu, S B; He, J Z

    2006-01-01

    CDMA is interference limited multiple access system. Power control is an effective way to reduce co-channel interference and solve the near-far problem. Consequently, it can improve the system capacity, and make higher data rate possible. CDMA2000 employs fast closed-loop power control in reverse link to combat channel fading, and the estimation of signal to interference ratio (SIR) is required for closed-loop power control. Transmitting power is adjusted by comparing the SIR estimation with SIR target. So, it is crucial to measure the SIR of received signal accurately. Traditional measurement methods mostly depend on pilot signal strongly, when the pilots are few, there is a greater error brought to the measurement of SIR. In this paper, we discuss the SIR measurement of the received signal under the fewer pilots condition (especially only one pilot symbol) and present a novel SIR measurement method. According to the simulation, the numerical results indicate that the SIR measured by the proposed method is more accurate than the SIR measured by conventional method under fewer pilots condition

  12. Sir Victor Horsley (1857-1916): pioneer of neurological surgery.

    Science.gov (United States)

    Tan, Tze-Ching; Black, Peter McL

    2002-03-01

    Immortalized in surgical history for the introduction of "antiseptic wax," Sir Victor Horsley played a pivotal role in shaping the face of standard neurosurgical practice. His contributions include the first laminectomy for spinal neoplasm, the first carotid ligation for cerebral aneurysm, the curved skin flap, the transcranial approach to the pituitary gland, intradural division of the trigeminal nerve root for trigeminal neuralgia, and surface marking of the cerebral cortex. A tireless scientist, he was a significant player in discovering the cure for myxedema, the eradication of rabies from England, and the invention of the Horsley-Clarke stereotactic frame. As a pathologist, Horsley performed research on bacteria and edema and founded the Journal of Pathology. Horsley's kindness, humility, and generous spirit endeared him to patients, colleagues, and students. Born to privilege, he was nonetheless dedicated to improving the lot of the common man and directed his efforts toward the suffrage of women, medical reform, and free health care for the working class. Knighted in 1902 for his many contributions to medicine, Sir Victor met an untimely death during World War I from heat stroke at the age of 59. An iconoclast of keen intellect, unlimited energy, and consummate skill, his life and work justify his epitaph as a "pioneer of neurological surgery."

  13. Sir William Osler's speech at Troy: a Trojan horse?

    Science.gov (United States)

    Moran, Michael E

    2012-01-01

    Troy, New York, is a city of 55,000 people in upstate New York located along the Hudson River. A city of surprisingly rich cultural heritage, it was the home of New York state's first hospital outside New York City. The 50th anniversary celebration of Troy's hospital brought William Osler to the city as the keynote speaker. This speech, delivered on November 28, 1900, is one of Sir William's less well known addresses. Osler began his comments with Sir Thomas More's Utopia and talked at length about the hospital, its obligations, the influences it has upon the community, and the role of physicians and surgeons. He broached one of his old saws, the salary of attending physicians and their needed role in hospital management. His words were published in the diamond jubilee's records, but the hospital did not outlive its prominent guest professor, and it closed its doors in 1914. Just like the great historical city of Troy, New York's own Troy was on the brink of decline, and its hospital would be the first fatality. Therefore, it is almost prescient that the words of Osler, taken into historical context juxtaposed against the socioeconomic forces at work, are akin to the Greek's offering of a wooden edifice to end the Trojan War.

  14. 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.

  15. 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

  16. 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.

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. 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.

  5. Lunar Science from and for Planet Earth

    Science.gov (United States)

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

    2008-09-01

    in the inner solar system and the environment under which early life was able to survive. We learned that the long-lived heat producing elements are concentrated on the lunar nearside and a major geologic event must have occurred very early during the evolution of the crust and mantle to accomplish this. We learned that significant volatile deposits occur at both lunar poles and may have resulted in water ice in their permanently shadowed regions. The embers then fire from this small influx of new information and understanding in the 1990s set the stage for the next generation of lunar exploration. International Lunar Exploration: The Golden Age In 2003 ESA launched what was to become a highly successful technology demonstration mission to the Moon, SMART-1. This small pathfinder has now been followed by some of the most sophisticated remote sensing robotic missions ever sent to the Moon. The SELENE/KAGUYA mission from JAXA and the Chang'E mission from China were launched in 2007 and are successfully returning remarkable data to Earth with unprecedented resolution and detail. The Chandrayaan-1 mission of ISRO with a complement of modern Indian as well foreign instruments is set to launch in 2008. The LRO/LCROSS pair of NASA will be next, followed by NASA's GRAIL geophysics mission in 2010. It is fitting that Earth's neighbour, which harbours so many secrets about our own origins and place in the universe, is now being explored independently by a virtual armada originating from space-faring nations across the Earth. The opportunities for peaceful coordination and cooperation abound, both at the personal scientist-to-scientist level as well as at the national policy level. The next 50 years of exploration of the Earth-Moon system will be truly remarkable with the new foundation of knowledge brought forth by this golden age of lunar exploration.

  6. 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.

  7. 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

  8. 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.

  9. Are Ferroan Anorthosites Direct Products of the Lunar Magma Ocean?

    Science.gov (United States)

    Neal, C. R.; Draper, D. S.

    2016-01-01

    According to Lunar Magma Ocean (LMO) theory, lunar samples that fall into the ferroan anorthosite (FAN) category represent the only samples we have of of the primordial crust of the Moon. Modeling indicates that plagioclase crystallizes after >70% LMO crystallization and formed a flotation crust, depending upon starting composition. The FAN group of highlands materials has been subdivided into mafic-magnesian, mafic-ferroan, anorthositic- sodic, and anorthositic-ferroan, although it is not clear how these subgroups are related. Recent radiogenic isotope work has suggested the range in FAN ages and isotopic systematics are inconsistent with formation of all FANs from the LMO. While an insulating lid could have theoretically extend the life of the LMO to explain the range of the published ages, are the FAN compositions consistent with crystallization from the LMO? As part of a funded Emerging Worlds proposal (NNX15AH76G), we examine this question through analysis of FAN samples. We compare the results with various LMO crystallization models, including those that incorporate the influence of garnet.

  10. Performance evaluation of lunar penetrating radar onboard the rover of CE-3 probe based on results from ground experiments

    Science.gov (United States)

    Zhang, Hong-Bo; Zheng, Lei; Su, Yan; Fang, Guang-You; Zhou, Bin; Feng, Jian-Qing; Xing, Shu-Guo; Dai, Shun; Li, Jun-Duo; Ji, Yi-Cai; Gao, Yun-Ze; Xiao, Yuan; Li, Chun-Lai

    2014-12-01

    Lunar Penetrating Radar (LPR) onboard the rover that is part of the Chang'e-3 (CE-3) mission was firstly utilized to obtain in situ measurements about geological structure on the lunar surface and the thickness of the lunar regolith, which are key elements for studying the evolutional history of lunar crust. Because penetration depth and resolution of LPR are related to the scientific objectives of this mission, a series of ground-based experiments using LPR was carried out, and results of the experimental data were obtained in a glacial area located in the northwest region of China. The results show that the penetration depth of the first channel antenna used for LPR is over 79 m with a resolution of 2.8 m, and that for the second channel antenna is over 50.8 m with a resolution of 17.1 cm.

  11. Performance evaluation of lunar penetrating radar onboard the rover of CE-3 probe based on results from ground experiments

    International Nuclear Information System (INIS)

    Zhang Hong-Bo; Zheng Lei; Su Yan; Feng Jian-Qing; Xing Shu-Guo; Dai Shun; Li Jun-Duo; Xiao Yuan; Li Chun-Lai; Fang Guang-You; Zhou Bin; Ji Yi-Cai; Gao Yun-Ze

    2014-01-01

    Lunar Penetrating Radar (LPR) onboard the rover that is part of the Chang'e-3 (CE-3) mission was firstly utilized to obtain in situ measurements about geological structure on the lunar surface and the thickness of the lunar regolith, which are key elements for studying the evolutional history of lunar crust. Because penetration depth and resolution of LPR are related to the scientific objectives of this mission, a series of ground-based experiments using LPR was carried out, and results of the experimental data were obtained in a glacial area located in the northwest region of China. The results show that the penetration depth of the first channel antenna used for LPR is over 79 m with a resolution of 2.8 m, and that for the second channel antenna is over 50.8 m with a resolution of 17.1 cm

  12. A Multi-Decadal Sample Return Campaign Will Advance Lunar and Solar System Science and Exploration by 2050

    Science.gov (United States)

    Neal, C. R.; Lawrence, S. J.

    2017-01-01

    There have been 11 missions to the Moon this century, 10 of which have been orbital, from 5 different space agencies. China became the third country to successfully soft-land on the Moon in 2013, and the second to successfully remotely operate a rover on the lunar surface. We now have significant global datasets that, coupled with the 1990s Clementine and Lunar Prospector missions, show that the sample collection is not representative of the lithologies present on the Moon. The M3 data from the Indian Chandrayaan-1 mission have identified lithologies that are not present/under-represented in the sample collection. LRO datasets show that volcanism could be as young as 100 Ma and that significant felsic complexes exist within the lunar crust. A multi-decadal sample return campaign is the next logical step in advancing our understanding of lunar origin and evolution and Solar System processes.

  13. 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

  14. Permanence for a Delayed Nonautonomous SIR Epidemic Model with Density-Dependent Birth Rate

    Directory of Open Access Journals (Sweden)

    Li Yingke

    2011-01-01

    Full Text Available Based on some well-known SIR models, a revised nonautonomous SIR epidemic model with distributed delay and density-dependent birth rate was considered. Applying some classical analysis techniques for ordinary differential equations and the method proposed by Wang (2002, the threshold value for the permanence and extinction of the model was obtained.

  15. Analytical, Experimental, and Modelling Studies of Lunar and Terrestrial Rocks

    Science.gov (United States)

    Haskin, Larry A.

    1997-01-01

    The goal of our research has been to understand the paths and the processes of planetary evolution that produced planetary surface materials as we find them. Most of our work has been on lunar materials and processes. We have done studies that obtain geological knowledge from detailed examination of regolith materials and we have reported implications for future sample-collecting and on-surface robotic sensing missions. Our approach has been to study a suite of materials that we have chosen in order to answer specific geologic questions. We continue this work under NAG5-4172. The foundation of our work has been the study of materials with precise chemical and petrographic analyses, emphasizing analysis for trace chemical elements. We have used quantitative models as tests to account for the chemical compositions and mineralogical properties of the materials in terms of regolith processes and igneous processes. We have done experiments as needed to provide values for geochemical parameters used in the models. Our models take explicitly into account the physical as well as the chemical processes that produced or modified the materials. Our approach to planetary geoscience owes much to our experience in terrestrial geoscience, where samples can be collected in field context and sampling sites revisited if necessary. Through studies of terrestrial analog materials, we have tested our ideas about the origins of lunar materials. We have been mainly concerned with the materials of the lunar highland regolith, their properties, their modes of origin, their provenance, and how to extrapolate from their characteristics to learn about the origin and evolution of the Moon's early igneous crust. From this work a modified model for the Moon's structure and evolution is emerging, one of globally asymmetric differentiation of the crust and mantle to produce a crust consisting mainly of ferroan and magnesian igneous rocks containing on average 70-80% plagioclase, with a large

  16. K-Ca and Rb-Sr Dating of Lunar Granite 14321 Revisited

    Science.gov (United States)

    Simon, Justin I.; Shih, C.-Y.; Nyquist, L. E.

    2011-01-01

    K-Ca and Rb-Sr age determinations were made for a bulk feldspar-rich portion of an Apollo rock fragment of the pristine lunar granite clast (14321,1062), an acid-leached split of the sample, and the leachate. K-Ca and Rb-Sr data were also obtained for a whole rock sample of Apollo ferroan anorthosite (FAN, 15415). The recent detection [1] of widespread intermediate composition plagioclase indicates that the generation of a diversity of evolved lunar magmas maybe more common and therefore more important to our understanding of crust formation than previously believed. Our new data strengthen the K-Ca and Rb-Sr internal isochrons of the well-studied Apollo sample 14321 [2], which along with a renewed effort to study evolved lunar magmas will provide an improved understanding of the petrogenetic history of evolved rocks on the Moon.

  17. The Moon is a Planet Too: Lunar Science and Robotic Exploration

    Science.gov (United States)

    Cohen, Barbara A.

    2009-01-01

    This slide presentation reviews some of what is known about the moon, and draws parallels between the moon and any other terrestrial planet. The Moon is a cornerstone for all rocky planets The Moon is a terrestrial body, formed and evolved similarly to Earth, Mars, Mercury, Venus, and large asteroids The Moon is a differentiated body, with a layered internal structure (crust, mantle, and core) The Moon is a cratered body, preserving a record of bombardment history in the inner solar system The Moon is an active body, experiencing moonquakes, releasing primordial heat, conducting electricity, sustaining bombardment, and trapping volatile molecules Lunar robotic missions provide early science return to obtain important science and engineering objectives, rebuild a lunar science community, and keep our eyes on the Moon. These lunar missions, both past and future are reviewed.

  18. Lunar bulk chemical composition: a post-Gravity Recovery and Interior Laboratory reassessment.

    Science.gov (United States)

    Taylor, G Jeffrey; Wieczorek, Mark A

    2014-09-13

    New estimates of the thickness of the lunar highlands crust based on data from the Gravity Recovery and Interior Laboratory mission, allow us to reassess the abundances of refractory elements in the Moon. Previous estimates of the Moon fall into two distinct groups: earthlike and a 50% enrichment in the Moon compared with the Earth. Revised crustal thicknesses and compositional information from remote sensing and lunar samples indicate that the crust contributes 1.13-1.85 wt% Al2O3 to the bulk Moon abundance. Mare basalt Al2O3 concentrations (8-10 wt%) and Al2O3 partitioning behaviour between melt and pyroxene during partial melting indicate mantle Al2O3 concentration in the range 1.3-3.1 wt%, depending on the relative amounts of pyroxene and olivine. Using crustal and mantle mass fractions, we show that that the Moon and the Earth most likely have the same (within 20%) concentrations of refractory elements. This allows us to use correlations between pairs of refractory and volatile elements to confirm that lunar abundances of moderately volatile elements such as K, Rb and Cs are depleted by 75% in the Moon compared with the Earth and that highly volatile elements, such as Tl and Cd, are depleted by 99%. The earthlike refractory abundances and depleted volatile abundances are strong constraints on lunar formation processes. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  19. Diversity of basaltic lunar volcanism associated with buried impact structures: Implications for intrusive and extrusive events

    Science.gov (United States)

    Zhang, F.; Zhu, M.-H.; Bugiolacchi, R.; Huang, Q.; Osinski, G. R.; Xiao, L.; Zou, Y. L.

    2018-06-01

    Relatively denser basalt infilling and the upward displacement of the crust-mantle interface are thought to be contributing factors for the quasi-circular mass anomalies for buried impact craters in the lunar maria. Imagery and gravity observations from the Lunar Reconnaissance Orbiter (LRO) and dual Gravity Recovery and Interior Laboratory (GRAIL) missions have identified 10 partially or fully buried impact structures where diversity of observable basaltic mare volcanism exists. With a detailed investigation of the characteristics of associated volcanic landforms, we describe their spatial distribution relationship with respect to the subsurface tectonic structure of complex impact craters and propose possible models for the igneous processes which may take advantage of crater-related zones of weakness and enable magmas to reach the surface. We conclude that the lunar crust, having been fractured and reworked extensively by cratering, facilitates substance and energy exchange between different lunar systems, an effect modulated by tectonic activities both at global and regional scales. In addition, we propose that the intrusion-caused contribution to gravity anomalies should be considered in future studies, although this is commonly obscured by other physical factors such as mantle uplift and basalt load.

  20. Magnetic Signature of the Lunar South Pole-Aitken Basin: Character, Origin, and Age

    Science.gov (United States)

    Purucker, Michael E.; Head, James W., III; Wilson, Lionel

    2012-01-01

    A new magnetic map of the Moon, based on Lunar Prospector (LP) magnetometer observations, sheds light on the origin of the South Pole-Aitken Basin (SPA), the largest and oldest of the recognized lunar basins. A set of WNW-trending linear to arcuate magnetic features, evident in both the radial and scalar observations, covers much of a 1000 km wide region centered on the NW portion of SPA. The source bodies are not at the surface because the magnetic features show no first-order correspondence to any surface topographic or structural feature. Patchy mare basalts of possible late Imbrianage are emplaced within SPA and are inferred to have been emplaced through dikes, directly from mantle sources. We infer that the magnetic features represent dike swarms that served as feeders for these mare basalts, as evident from the location of the Thomson/ Mare Ingenii, Van de Graaff, and Leeuwenhoek mare basalts on the two largest magnetic features in the region. Modeling suggests that the dike zone is between 25 and 50 km wide at the surface, and dike magnetization contrasts are in the range of 0.2 A/m. We theorize that the basaltic dikes were emplaced in the lunar crust when a long-lived dynamo was active. Based on pressure, temperature, and stress conditions prevalent in the lunar crust, dikes are expected to be a dominantly subsurface phenomenon, consistent with the observations reported here.

  1. Dynamical Analysis of SIR Epidemic Models with Distributed Delay

    Directory of Open Access Journals (Sweden)

    Wencai Zhao

    2013-01-01

    Full Text Available SIR epidemic models with distributed delay are proposed. Firstly, the dynamical behaviors of the model without vaccination are studied. Using the Jacobian matrix, the stability of the equilibrium points of the system without vaccination is analyzed. The basic reproduction number R is got. In order to study the important role of vaccination to prevent diseases, the model with distributed delay under impulsive vaccination is formulated. And the sufficient conditions of globally asymptotic stability of “infection-free” periodic solution and the permanence of the model are obtained by using Floquet’s theorem, small-amplitude perturbation skills, and comparison theorem. Lastly, numerical simulation is presented to illustrate our main conclusions that vaccination has significant effects on the dynamical behaviors of the model. The results can provide effective tactic basis for the practical infectious disease prevention.

  2. Sir Robert Ball: Victorian Astronomer and Lecturer par excellence

    Science.gov (United States)

    Jones, R. I. G.

    2005-12-01

    Between 1875 and 1910 Sir Robert Stawell Ball gave an estimated 2,500 lectures in towns and cities all over the British Isles and abroad. This paper traces his lecturing career from its beginnings in Ireland to the triumphs of the Royal Institution, and on lecture tours in the United States of America. After a period in mathematics and mechanics, he became a populariser of science, especially astronomy, and found fame and fortune among the working classes and the aristocracy. What motivated him to tireless travels is uncertain, but it might have been that it was rewarding, financially and to his reputation. Whatever his motives, contemporary accounts are clear that BallÕs lectures were extremely popular and well-received.

  3. Microstrip Cross-coupled Interdigital SIR Based Bandpass Filter

    Directory of Open Access Journals (Sweden)

    R. K. Maharjan

    2012-09-01

    Full Text Available A simple and compact 4.9 GHz bandpass filter for C-band applications is proposed. This paper presents a novel microstrip cross-coupled interdigital half-wavelength stepped impedance resonator (SIR based bandpass filter (BPF.The designed structure is similar to that of a combination of two parallel interdigital capacitors. The scattering parameters of the structure are measured using vector network analyzer (VNA. The self generated capacitive and inductive reactances within the interdigital resonators exhibited in a resonance frequency of 4.9 GHz. The resonant frequency and bandwidth of the capacitive cross-coupled resonator is directly optimized from the physical arrangement of the resonators. The measured insertion loss (S21 and return loss (S11 were 0.3 dB and 28 dB, respectively, at resonance frequency which were almost close to the simulation results.

  4. Vaccination strategies for SIR vector-transmitted diseases.

    Science.gov (United States)

    Cruz-Pacheco, Gustavo; Esteva, Lourdes; Vargas, Cristobal

    2014-08-01

    Vector-borne diseases are one of the major public health problems in the world with the fastest spreading rate. Control measures have been focused on vector control, with poor results in most cases. Vaccines should help to reduce the diseases incidence, but vaccination strategies should also be defined. In this work, we propose a vector-transmitted SIR disease model with age-structured population subject to a vaccination program. We find an expression for the age-dependent basic reproductive number R(0), and we show that the disease-free equilibrium is locally stable for R(0) ≤ 1, and a unique endemic equilibrium exists for R(0) > 1. We apply the theoretical results to public data to evaluate vaccination strategies, immunization levels, and optimal age of vaccination for dengue disease.

  5. SIR (Safe Integral Reactor) - reducing size can reduce cost

    International Nuclear Information System (INIS)

    Hayns, M.R.

    1991-01-01

    Traditional engineering economics have favoured the advantages of larger size as a means of reducing specific capital costs and hence unit generating costs. For large and small plants utilising the same concept, e.g. a small four-loop PWR vs a large four-loop PWR with the same number of components, economies of scale are well established. If, however, a smaller plant is sized to take advantage of features which are only feasible at smaller outputs, is of simpler design, with the advantage taken of the simplified design to produce the most cost-effective layout, and incorporates fewer, more easily replaceable components with minimal assembly on site, it is possible to produce a plant which is competitive with larger plant of more traditional design. When 'system' effects, such as better matching of installed capacity to the growth in demand and the fact that a smaller total capacity will be needed to meet a given demand with a specified level of confidence, are taken into account, it can be shown that a utility's overall cash-flow position can be improved with lower associated absolute financial risks. The UK/US Safe Integral Reactor (SIR) is an integral pressurized water reactor in the 300-400 MW(e) range which utilises conventional water reactor technology in a way not feasible at the very large, sizes of recent years. The SIR concept is briefly explained and its technical and economic advantages in terms of simplicity, construction, maintenance, availability, decommissioning, safety and siting described. The results of system analyses which demonstrate the overall financial advantages to a utility are presented. (author)

  6. Digging Deep: Is Lunar Mantle Excavated Around the Imbrium Basin?

    Science.gov (United States)

    Klima, R. L.; Bretzfelder, J.; Buczkowski, D.; Ernst, C. M.; Greenhagen, B. T.; Petro, N. E.; Shusterman, M. L.

    2017-12-01

    The Moon has experienced over a dozen impacts resulting in basins large enough to have excavated mantle material. With many of those basins concentrated on the lunar near side, and extensive regolith mixing since the lunar magma ocean crystallized, one might expect that some mantle material would have been found among the lunar samples on Earth. However, so far, no mantle clasts have been definitively identified in lunar samples [1]. From orbit, a number of olivine-bearing localities, potentially sourced from the mantle, have been identified around impact basins [2]. Based on analysis of near-infrared (NIR) and imaging data, [3] suggest that roughly 60% of these sites represent olivine from the mantle. If this is the case and the blocks are coherent and not extensively mixed into the regolith, these deposits should be ultramafic, containing olivine and/or pyroxenes and little to no plagioclase. In the mid-infrared, they would thus exhibit Christiansen features at wavelengths in excess of 8.5 μm, which has not been observed in global studies using the Diviner Lunar Radiometer [4]. We present an integrated study of the massifs surrounding the Imbrium basin, which, at over 1000 km wide, is large enough to have penetrated through the lunar crust and into the mantle. These massifs are clearly associated with the Imbrium basin-forming impact, but existing geological maps do not distinguish between whether they are likely ejecta or rather uplifted from beneath the surface during crustal rebound [5]. We examine these massifs using vis, NIR and Mid IR data to determine the relationships between and the bulk mineralogy of local lithologies. NIR data suggest that the massifs contain exposures of four dominant minerals: olivine, Mg-rich orthopyroxene, a second low-Ca pyroxene, and anorthite. Mid IR results suggest that though many of these massifs are plagioclase-rich, portions of some may be significantly more mafic. We will present our growing mineralogical map of the

  7. Return to the far side of planet Moore! rambling through observations, friendships and antics of sir Patrick Moore

    CERN Document Server

    Mobberley, Martin

    2015-01-01

    The result of an exhaustive study of Sir Patrick Moore’s observations of the Moon and planets for more than 60 years, this book is a fantastic companion to the extremely popular, “It Came From Outer Space Wearing an RAF Blazer!” written by the same author.  Moore recorded his telescopic observations in his logbooks, which are reproduced and described here in detail, along with his sketches and notes. In this light, the author discusses the factors that caused Moore to switch from lunar observing to planetary and variable star observing.  He has also included personal recollections and humorous anecdotes from Moore’s friends and acquaintances, as well as a look at his best loved books. Further chapters describe Moore’s foreign travels and correspondence with those back home. Lastly, the author has not neglected a few of Moore’s most memorable television and radio appearances, which are examined along with a close up of what it was like to visit Moore’s beloved home of Farthings in Selsey. Essen...

  8. 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.

  9. Transdomes sampling of lower and middle crust

    Science.gov (United States)

    Teyssier, C. P.; Whitney, D. L.; Roger, F.; Rey, P. F.

    2015-12-01

    Migmatite transdomes are formed by lateral and upward flow of partially molten crust in transtension zones (pull-apart structures). In order to understand the flow leading to this type of domes, 3D numerical models were set-up to simulate the general case of an extensional domain located between two strike-slip faults (pull-apart or dilational bridge). Results show that upper crust extension induces flow of the deep, low-viscosity crust, with rapid upward movement of transdome material when extension becomes localized. At this point a rolling hinge detachment allows rapid removal of upper crust. The internal structure of transdomes includes a subvertical high strain zone located beneath the zone of localized upper crust extension; this shear zone separates two elongate subdomes of foliation that show refolded/sheath folds. Lineation tends to be oriented dominantly subhorizontal when the amount of strike-slip motion is greater than the amount of upward flow of dome rocks. Models also predict nearly isothermal decompression of transdome material and rapid transfer of ~50 km deep rocks to the near surface. These model results are compared to the structural and metamorphic history of several transdomes, and in particular the Variscan Montagne Noire dome (French Massif Central) that consists of two domes separated by a complex high strain zone. The Montagne Noire dome contains ~315 Ma eclogite bodies (U-Pb zircon age) that record 1.4 GPa peak pressure. The eclogite bodies are wrapped in highly sheared migmatite that yield 314-310 Ma monazite ages interpreted as the metamorphism and deformation age. Based on these relations we conclude that the Montagne Noire transdome developed a channel of partially molten crust that likely entrained eclogite bodies from the deep crust (~50 km) before ascending to the near-surface. One implication of this work is that the flowing crust was deeply seated in the orogen although it remained a poor recorder of peak pressure of metamorphism

  10. 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.

  11. NASA Lunar Impact Monitoring

    Science.gov (United States)

    Suggs, Robert M.; Moser, D. E.

    2015-01-01

    The MSFC lunar impact monitoring program began in 2006 in support of environment definition for the Constellation (return to Moon) program. Work continued by the Meteoroid Environment Office after Constellation cancellation. Over 330 impacts have been recorded. A paper published in Icarus reported on the first 5 years of observations and 126 calibrated flashes. Icarus: http://www.sciencedirect.com/science/article/pii/S0019103514002243; ArXiv: http://arxiv.org/abs/1404.6458 A NASA Technical Memorandum on flash locations is in press

  12. Lunar architecture and urbanism

    Science.gov (United States)

    Sherwood, Brent

    1992-01-01

    Human civilization and architecture have defined each other for over 5000 years on Earth. Even in the novel environment of space, persistent issues of human urbanism will eclipse, within a historically short time, the technical challenges of space settlement that dominate our current view. By adding modern topics in space engineering, planetology, life support, human factors, material invention, and conservation to their already renaissance array of expertise, urban designers can responsibly apply ancient, proven standards to the exciting new opportunities afforded by space. Inescapable facts about the Moon set real boundaries within which tenable lunar urbanism and its component architecture must eventually develop.

  13. Hydrogen Distribution in the Lunar Polar Regions

    Science.gov (United States)

    Sanin, A. B.; Mitrofanov, I. G.; Litvak, M. L.; Bakhtin, B. N.; Bodnarik, J. G.; Boynton, W. V.; Chin, G.; Evans, L. G.; Harshmann, K.; Fedosov, F.; hide

    2016-01-01

    We present a method of conversion of the lunar neutron counting rate measured by the Lunar Reconnaissance Orbiter (LRO) Lunar Exploration Neutron Detector (LEND) instrument collimated neutron detectors, to water equivalent hydrogen (WEH) in the top approximately 1 m layer of lunar regolith. Polar maps of the Moon’s inferred hydrogen abundance are presented and discussed.

  14. 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.

  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. Nicotinamide clearance by Pnc1 directly regulates Sir2-mediated silencing and longevity.

    Science.gov (United States)

    Gallo, Christopher M; Smith, Daniel L; Smith, Jeffrey S

    2004-02-01

    The Saccharomyces cerevisiae Sir2 protein is an NAD(+)-dependent histone deacetylase (HDAC) that functions in transcriptional silencing and longevity. The NAD(+) salvage pathway protein, Npt1, regulates Sir2-mediated processes by maintaining a sufficiently high intracellular NAD(+) concentration. However, another NAD(+) salvage pathway component, Pnc1, modulates silencing independently of the NAD(+) concentration. Nicotinamide (NAM) is a by-product of the Sir2 deacetylase reaction and is a natural Sir2 inhibitor. Pnc1 is a nicotinamidase that converts NAM to nicotinic acid. Here we show that recombinant Pnc1 stimulates Sir2 HDAC activity in vitro by preventing the accumulation of NAM produced by Sir2. In vivo, telomeric, rDNA, and HM silencing are differentially sensitive to inhibition by NAM. Furthermore, PNC1 overexpression suppresses the inhibitory effect of exogenously added NAM on silencing, life span, and Hst1-mediated transcriptional repression. Finally, we show that stress suppresses the inhibitory effect of NAM through the induction of PNC1 expression. Pnc1, therefore, positively regulates Sir2-mediated silencing and longevity by preventing the accumulation of intracellular NAM during times of stress.

  17. 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

  18. DaMaSCUS-CRUST: Dark Matter Simulation Code for Underground Scatterings - Crust Edition

    Science.gov (United States)

    Emken, Timon; Kouvaris, Chris

    2018-03-01

    DaMaSCUS-CRUST determines the critical cross-section for strongly interacting DM for various direct detection experiments systematically and precisely using Monte Carlo simulations of DM trajectories inside the Earth's crust, atmosphere, or any kind of shielding. Above a critical dark matter-nucleus scattering cross section, any terrestrial direct detection experiment loses sensitivity to dark matter, since the Earth crust, atmosphere, and potential shielding layers start to block off the dark matter particles. This critical cross section is commonly determined by describing the average energy loss of the dark matter particles analytically. However, this treatment overestimates the stopping power of the Earth crust; therefore, the obtained bounds should be considered as conservative. DaMaSCUS-CRUST is a modified version of DaMaSCUS (ascl:1706.003) that accounts for shielding effects and returns a precise exclusion band.

  19. Lunar Exploration Missions Since 2006

    Science.gov (United States)

    Lawrence, S. J. (Editor); Gaddis, L. R.; Joy, K. H.; Petro, N. E.

    2017-01-01

    The announcement of the Vision for Space Exploration in 2004 sparked a resurgence in lunar missions worldwide. Since the publication of the first "New Views of the Moon" volume, as of 2017 there have been 11 science-focused missions to the Moon. Each of these missions explored different aspects of the Moon's geology, environment, and resource potential. The results from this flotilla of missions have revolutionized lunar science, and resulted in a profoundly new emerging understanding of the Moon. The New Views of the Moon II initiative itself, which is designed to engage the large and vibrant lunar science community to integrate the results of these missions into new consensus viewpoints, is a direct outcome of this impressive array of missions. The "Lunar Exploration Missions Since 2006" chapter will "set the stage" for the rest of the volume, introducing the planetary community at large to the diverse array of missions that have explored the Moon in the last decade. Content: This chapter will encompass the following missions: Kaguya; ARTEMIS (Acceleration, Reconnection, Turbulence, and Electrodynamics of the Moon’s Interaction with the Sun); Chang’e-1; Chandrayaan-1; Moon Impact Probe; Lunar Reconnaissance Orbiter (LRO); Lunar Crater Observation Sensing Satellite (LCROSS); Chang’e-2; Gravity Recovery and Interior Laboratory (GRAIL); Lunar Atmosphere and Dust Environment Explorer (LADEE); Chang’e-3.

  20. SirR, a Novel Iron-Dependent Repressor in Staphylococcus epidermidis

    Science.gov (United States)

    Hill, Philip J.; Cockayne, Alan; Landers, Patrick; Morrissey, Julie A.; Sims, Catriona M.; Williams, Paul

    1998-01-01

    In Staphylococcus epidermidis and Staphylococcus aureus, a number of cell wall- and cytoplasmic membrane-associated lipoproteins are induced in response to iron starvation. To gain insights into the molecular basis of iron-dependent gene regulation in the staphylococci, we sequenced the DNA upstream of the 3-kb S. epidermidis sitABC operon, which Northern blot analysis indicates is transcriptionally regulated by the growth medium iron content. We identified two DNA sequences which are homologous to elements of the Corynebacterium diphtheriae DtxR regulon, which controls, in response to iron stress, for example, production of diphtheria toxin, siderophore, and a heme oxygenase. Upstream of the sitABC operon and divergently transcribed lies a 645-bp open reading frame (ORF), which codes for a polypeptide of approximately 25 kDa with homology to the DtxR family of metal-dependent repressor proteins. This ORF has been designated SirR (staphylococcal iron regulator repressor). Within the sitABC promoter/operator region, we also located a region of dyad symmetry overlapping the transcriptional start of sitABC which shows high homology to the DtxR operator consensus sequence, suggesting that this region, termed the Sir box, is the SirR-binding site. The SirR protein was overexpressed, purified, and used in DNA mobility shift assays; SirR retarded the migration of a synthetic oligonucleotide based on the Sir box in a metal (Fe2+ or Mn2+)-dependent manner, providing confirmatory evidence that this motif is the SirR-binding site. Furthermore, Southern blot analysis of staphylococcal chromosomal DNA with the synthetic Sir box as a probe confirmed that there are at least five Sir boxes in the S. epidermidis genome and at least three in the genome of S. aureus, suggesting that SirR controls the expression of multiple target genes. Using a monospecific polyclonal antibody raised against SirR to probe Western blots of whole-cell lysates of S. aureus, S. carnosus, S. epidermidis

  1. Tests of the lunar hypothesis

    Science.gov (United States)

    Taylor, S. R.

    1984-01-01

    The concept that the Moon was fissioned from the Earth after core separation is the most readily testable hypothesis of lunar origin, since direct comparisons of lunar and terrestrial compositions can be made. Differences found in such comparisons introduce so many ad hoc adjustments to the fission hypothesis that it becomes untestable. Further constraints may be obtained from attempting to date the volatile-refractory element fractionation. The combination of chemical and isotopic problems suggests that the fission hypothesis is no longer viable, and separate terrestrial and lunar accretion from a population of fractionated precursor planetesimals provides a more reasonable explanation.

  2. Development of a lunar infrastructure

    Science.gov (United States)

    Burke, J. D.

    1988-01-01

    The problem of building an infrastructure on the moon is discussed, assuming that earth-to-moon and moon-to-earth transport will be available. The sequence of events which would occur in the process of building an infrastructure is examined. The human needs which must be met on a lunar base are discussed, including minimal life support, quality of life, and growth stages. The technology available to meet these needs is reviewed and further research in fields related to a lunar base, such as the study of the moon's polar regions and the limits of lunar agriculture, is recommended.

  3. Crust formation in drying colloidal suspensions

    KAUST Repository

    Style, R. W.

    2010-06-30

    During the drying of colloidal suspensions, the desiccation process causes the suspension near the air interface to consolidate into a connected porous matrix or crust. Fluid transport in the porous medium is governed by Darcy\\'s law and the equations of poroelasticity, while the equations of colloid physics govern processes in the suspension. We derive new equations describing this process, including unique boundary conditions coupling the two regions, yielding a moving-boundary model of the concentration and stress profiles during drying. A solution is found for the steady-state growth of a nedimensional crust during constant evaporation rate from the surface. The solution is used to demonstrate the importance of the system boundary conditions on stress profiles and diffusivity in a drying crust. © 2011 The Royal Society.

  4. Year 3 LUNAR Annual Report to the NASA Lunar Science Institute

    OpenAIRE

    Burns, Jack; Lazio, Joseph

    2012-01-01

    The Lunar University Network for Astrophysics Research (LUNAR) is a team of researchers and students at leading universities, NASA centers, and federal research laboratories undertaking investigations aimed at using the Moon as a platform for space science. LUNAR research includes Lunar Interior Physics & Gravitation using Lunar Laser Ranging (LLR), Low Frequency Cosmology and Astrophysics (LFCA), Planetary Science and the Lunar Ionosphere, Radio Heliophysics, and Exploration Science. The LUN...

  5. Moonage Daydream: Reassessing the Simple Model for Lunar Magma Ocean Crystallization

    Science.gov (United States)

    Rapp, J. F.; Draper, D. S.

    2016-01-01

    Details of the differentiation of a global-scale lunar magma ocean (LMO) remain enigmatic, as the Moon is not simply composed of highlands anorthosite and a suite of mare basalts as inferred from early studies. Results from recent orbital missions, and the increasingly detailed study of lunar samples, have revealed a much larger range of lithologies, from relatively MgO-rich and "purest anorthosite" discovered on the lunar far side by the M3 instrument on Chandraayan-1 to more exotic lithologies such as Si-rich domes and spinel-rich clasts distributed globally. To understand this increasingly complex geology, we must understand the initial formation and evolution of the LMO, and the composition of the cumulates this differentiation could have produced. Several attempts at modelling such a crystallization sequence have been made, and have raised as many questions as they have answered. We present results from our ongoing experimental simulations of magma ocean crystallization, investigating two end-member bulk compositions (TWM and LPUM) under fully fractional crystallization conditions. These simulations represent melting of the entire silicate portion of the Moon, as an end-member starting point from which to begin assessing the evolution of the lunar interior and formation of the lunar crust.

  6. [Sir Arthur Conan Doyle, Sherlock Holmes and infectious diseases].

    Science.gov (United States)

    Ledermann D, Walter

    2010-10-01

    Besides a pleasant author of best sellers, Sir Arthur Conan Doyle was a medical doctor, writing excellent short stories about the exercise of his profession in England. However, even he mentions The British Medical Journal and The Lancet in the Sherlock Holmes's stories, when in the plot introduces infectious diseases, Conan Doyle ignores important discoveries in the field of tetanus. Anyway, the appearing of infectious diseases in the adventures of the detective are rare: one mention of tetanus, another of leprosy and- the most analyzed in medical literature a case of murder by inoculation of bacteria, probably the agent of melioidosis. Also he makes his hero discovers the toxic actions of a medusa and a transplant of solid organ. Little for a physician and less for an author who also wrote science fiction: it seems that the history of the great medical discoveries at the end of nineteenth century and beginning of the twentieth has passed by his side.., and he just couldn't see it.

  7. Italian Society of Rheumatology (SIR recommendations for performing arthrocentesis

    Directory of Open Access Journals (Sweden)

    A. Spadaro

    2011-09-01

    Full Text Available Joint fluid aspiration, or arthrocentesis, is one of the most useful and commonly performed procedures for the diagnosis and treatment of rheumatic diseases, but to date no definite guidelines have been published. For this reason, a group of experts of the Italian Society of Rheumatology (SIR produced evidence based recommendations for performing arthrocentesis. Among them, the most relevant are: a arthrocentesis is necessary when synovial effusion of unknown origin is present, especially if septic or crystal arthritis is suspected; b the patient should be clearly informed of the benefits and risks of the procedure in order to give an informed consent; c ultrasonography should be used to facilitate arthrocentesis in difficult joints; d fluid evacuation often has a therapeutic effect and facilitates the success of the following intraarticular injection; e careful skin disinfection and the use of sterile, disposable material is mandatory for avoiding septic complications. Disposable, non sterile gloves should always be used by the operator, mainly for his own protection; f contraindications are the presence of skin lesions or infections in the area of the puncture; g the patient’s anticoagulant treatment is not a contraindication, providing the therapeutic range is not exceeded; h joint rest after arthrocentesis is not indicated. Several of these recommendations were based on experts’ opinion rather than on published evidence which is scanty.

  8. Hafnium isotope stratigraphy of ferromanganese crusts

    Science.gov (United States)

    Lee; Halliday; Hein; Burton; Christensen; Gunther

    1999-08-13

    A Cenozoic record of hafnium isotopic compositions of central Pacific deep water has been obtained from two ferromanganese crusts. The crusts are separated by more than 3000 kilometers but display similar secular variations. Significant fluctuations in hafnium isotopic composition occurred in the Eocene and Oligocene, possibly related to direct advection from the Indian and Atlantic oceans. Hafnium isotopic compositions have remained approximately uniform for the past 20 million years, probably reflecting increased isolation of the central Pacific. The mechanisms responsible for the increase in (87)Sr/(86)Sr in seawater through the Cenozoic apparently had no effect on central Pacific deep-water hafnium.

  9. Lunar Reconnaissance Orbiter Lunar Workshops for Educators, Year 1 Report

    Science.gov (United States)

    Jones, A. P.; Hsu, B. C.; Bleacher, L.; Shaner, A. J.; Dalton, H.

    2011-12-01

    This past summer, the Lunar Reconnaissance Orbiter (LRO) sponsored a series of weeklong professional development workshops designed to educate and inspire grade 6-12 science teachers: the Lunar Workshops for Educators. Participants learned about lunar science and exploration, gained tools to help address common student misconceptions about the Moon, heard some of the latest research results from LRO scientists, worked with LRO data, and learned how to bring these data to their students using hands-on activities aligned with grade 6-12 National Science Education Standards and Benchmarks. Where possible, the workshops also included tours of science facilities or field trips intended to help the teachers better understand mission operations or geologic processes relevant to the Moon. The workshops were very successful. Participants demonstrated an improved understanding of lunar science concepts in post-workshop assessments (as compared to identical pre-assessments) and a greater understanding of how to access and productively share data from LRO with their students and provide them with authentic research experiences. Participant feedback on workshop surveys was also enthusiastically positive. 5 additional Lunar Workshops for Educators will be held around the country in the summer of 2012. For more information and to register, visit http://lunar.gsfc.nasa.gov/lwe/index.html.

  10. Early lunar magnetism

    Science.gov (United States)

    Banerjee, S. K.; Mellema, J. P.

    1976-01-01

    A new method (Shaw, 1974) for investigating paleointensity (the ancient magnetic field) was applied to three subsamples of a single, 1-m homogeneous clast from a recrystallized boulder of lunar breccia. Several dating methods established 4 billion years as the age of boulder assembly. Results indicate that the strength of the ambient magnetic field at the Taurus-Littrow region of the moon was about 0.4 oersted at 4 billion years ago. Values as high as 1.2 oersted have been reported (Collison et al., 1973). The required fields are approximately 10,000 times greater than present interplanetary or solar flare fields. It is suggested that this large field could have arisen from a pre-main sequence T-Tauri sun.

  11. Electrochemistry of lunar rocks

    Science.gov (United States)

    Lindstrom, D. J.; Haskin, L. A.

    1979-01-01

    Electrolysis of silicate melts has been shown to be an effective means of producing metals from common silicate materials. No fluxing agents need be added to the melts. From solution in melts of diopside (CaMgSi2O6) composition, the elements Si, Ti, Ni, and Fe have been reduced to their metallic states. Platinum is a satisfactory anode material, but other cathode materials are needed. Electrolysis of compositional analogs of lunar rocks initially produces iron metal at the cathode and oxygen gas at the anode. Utilizing mainly heat and electricity which are readily available from sunlight, direct electrolysis is capable of producing useful metals from common feedstocks without the need for expendable chemicals. This simple process and the products obtained from it deserve further study for use in materials processing in space.

  12. A relatively reduced Hadean continental crust

    Science.gov (United States)

    Yang, Xiaozhi; Gaillard, Fabrice; Scaillet, Bruno

    2014-05-01

    Among the physical and chemical parameters used to characterize the Earth, oxidation state, as reflected by its prevailing oxygen fugacity (fO2), is a particularly important one. It controls many physicochemical properties and geological processes of the Earth's different reservoirs, and affects the partitioning of elements between coexisting phases and the speciation of degassed volatiles in melts. In the past decades, numerous studies have been conducted to document the evolution of mantle and atmospheric oxidation state with time and in particular the possible transition from an early reduced state to the present oxidized conditions. So far, it has been established that the oxidation state of the uppermost mantle is within ±2 log units of the quartz-fayalite-magnetite (QFM) buffer, probably back to ~4.4 billion years ago (Ga) based on trace-elements studies of mantle-derived komatiites, kimberlites, basalts, volcanics and zircons, and that the O2 levels of atmosphere were initially low and rose markedly ~2.3 Ga known as the Great Oxidation Event (GOE), progressively reaching its present oxidation state of ~10 log units above QFM. In contrast, the secular evolution of oxidation state of the continental crust, an important boundary separating the underlying upper mantle from the surrounding atmosphere and buffering the exchanges and interactions between the Earth's interior and exterior, has rarely been addressed, although the presence of evolved crustal materials on the Earth can be traced back to ~4.4 Ga, e.g. by detrital zircons. Zircon is a common accessory mineral in nature, occurring in a wide variety of igneous, sedimentary and metamorphic rocks, and is almost ubiquitous in crustal rocks. The physical and chemical durability of zircons makes them widely used in geochemical studies in terms of trace-elements, isotopes, ages and melt/mineral inclusions; in particular, zircons are persistent under most crustal conditions and can survive many secondary

  13. Google Moon Lunar Mapping Data

    Data.gov (United States)

    National Aeronautics and Space Administration — A collection of lunar maps and charts. This tool is an exciting new way to explore the story of the Apollo missions, still the only time mankind has set foot on...

  14. First oxygen from lunar basalt

    Science.gov (United States)

    Gibson, M. A.; Knudsen, C. W.; Brueneman, D. J.; Kanamori, H.; Ness, R. O.; Sharp, L. L.; Brekke, D. W.; Allen, C. C.; Morris, R. V.; Keller, L. P.

    1993-01-01

    The Carbotek/Shimizu process to produce oxygen from lunar soils has been successfully demonstrated on actual lunar samples in laboratory facilities at Carbotek with Shimizu funding and support. Apollo sample 70035 containing approximately 25 percent ilmenite (FeTiO3) was used in seven separate reactions with hydrogen varying temperature and pressure: FeTiO3 + H2 yields Fe + TiO2 + H2O. The experiments gave extremely encouraging results as all ilmenite was reduced in every experiment. The lunar ilmenite was found to be about twice as reactive as terrestrial ilmenite samples. Analytical techniques of the lunar and terrestrial ilmenite experiments performed by NASA Johnson Space Center include iron Mossbauer spectroscopy (FeMS), optical microscopy, SEM, TEM, and XRD. The Energy and Environmental Research Center at the University of North Dakota performed three SEM techniques (point count method, morphology determination, elemental mapping), XRD, and optical microscopy.

  15. 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.

  16. 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.

  17. Lunar Health Monitor, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — During the Phase II Lunar Health Monitor program, Orbital Research will develop a second generation wearable sensor suite for astronaut physiologic monitoring. The...

  18. 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

  19. Sir James Paget: Paget's disease of the nipple, Paget's disease of bone.

    Science.gov (United States)

    Ellis, Harold

    2013-04-01

    Sir James Paget was one of the 'great' Victorians. Eminent as a surgeon, pathologist and teacher, his nobility of character and application to his work made him a leader in his profession in that age of great men.

  20. SIR-A views our environment An Experiment in the Batu Angkal Area, West Kalimantan, Indonesia

    Directory of Open Access Journals (Sweden)

    Sutanto .

    2013-07-01

    Factors affecting the ease of identification are. mainly tonal contrast, shape, size, surface roughness, direction in relation to the illumination, and dielectric constant. Due to the future availability of SIR-B image of Kalimantan, further study is recommended.

  1. Identifying settlements on the SIR-B images of Rimbobujang and the surrounding areas, Sumatra, Indonesia

    Directory of Open Access Journals (Sweden)

    Sutanto .

    2013-07-01

    SIR-B image proves to be a reasonably good tool to identify rural settlement in an open area, especially for that with high density of houses. Its use to identify towns and cities is more recommended.

  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. The magnetization of the lunar crust as deduced from orbital surveys

    Science.gov (United States)

    Hood, L. L.; Russell, C. T.; Coleman, P. J., Jr.

    1978-01-01

    A two-dimensional magnetic anomaly map of a region of intense crustal magnetization near Van de Graaff crater has been constructed from Apollo 15 and 16 subsatellite vector magnetometer observations. The mapping method used limits coverage to relatively low altitudes (65-80 km) over the Van de Graaff region along the Apollo 15 track and over the central far side highlands along the Apollo 16 track; a simple differencing technique was used to remove external noise contributions. An approximate inversion of this map using a surface plate model for source region geometry has revealed at least four different sources. No correlation between the lateral locations of these source regions and surface morphology was found; the directions of magnetization seem to be unrelated except for a strong north-south depletion. A rough antipodal correlation of the two most strongly magnetized regions yet mapped on the moon with the Imbrium and Orientale basins gives mild support to the ejecta deposit hypothesis suggested by Strangway et al. (1973) for formation of anomaly source regions.

  4. SIR JOHN CRAWFORD MEMORIAL ADDRESS: Agriculture: The challenges of the 21st century

    OpenAIRE

    Beddington, Sir John

    2012-01-01

    The Sir John Crawford Memorial Address has been presented since 1985, in honour of the distinguished Australian civil servant, educator and agriculturalist in whose name the Crawford Fund was established. Sir John Crawford was a remarkable Australian who contributed at the highest levels, and was a passionate supporter of international agricultural research for development. This talk draws attention to four current and interrelated trends that suggest the world will be rather different by 202...

  5. 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).

  6. Dew formation and activity of biological crusts

    NARCIS (Netherlands)

    Veste, M.; Heusinkveld, B.G.; Berkowicz, S.M.; Breckle, S.W.; Littmann, T.; Jacobs, A.F.G.

    2008-01-01

    Biological soil crusts are prominent in many drylands and can be found in diverse parts of the globe including the Atacama desert, Chile, the Namib desert, Namibia, the Succulent-Karoo desert, South Africa, and the Negev desert, Israel. Because precipitation can be negligible in deserts ¿ the

  7. Crust-mantle contribution to Andean magmatism

    International Nuclear Information System (INIS)

    Ruiz, J; Hildreth, W; Chesley, J

    2001-01-01

    There has long been great interest in quantifying the contributions of the continental crust to continental arc magmas, such as those of the Andes using osmium isotopes (Alves et al., 1999; Borg et al., 2000; Brandon et al., 1996; McInnes et al., 1999). In general, Andean volcanic rocks of all compositions show relatively low Sr-isotope ratios and positive to mildly negative epsilon Nd values. Nonetheless, in the Southern Volcanic Zone of central Chile, basalt-andesite-dacite volcanoes along the Quaternary volcanic front were shown (by Hildreth and Moorbath, 1988) to have latitudinally systematic chemical variations, as well as a monotonic increase in 87Sr/Sr86 from ca. 0.7035 to 0.7055 and a decrease in epsilon Nd values from ca. +3 to -1. The isotopic variations correlate with basement elevation of the volcanic edifices and with Bouguer gravity anomalies, both of which are thought to reflect along-arc variations in thickness and average age of the underlying crust. Volcanoes with the most evolved isotopic signatures were fed through the thickest crust. Correlation of chemical and isotopic variations with crustal thickness was interpreted to be caused by Melting (of deep-crustal host rocks), Assimilation, Storage, and Homogenization (MASH) of mantle-derived magmas in long-lived lower-crustal reservoirs beneath each center prior to eruption. We have now determined Os-isotope ratios for a sample suite from these volcanoes (33-36 S lat.), representing a range of crustal thickness from ca. 60-35 km. The samples range in MgO from ca. 8-4% and in SiO2 from 51-57%. The most evolved eruptive products occur above the thickest crust and have 87Sr/86Sr ratios of 0.7054 and epsilon Nd values of -1.5. The 187Os/188Os ratios correlate with the other isotopic systems and with crustal thickness. Volcanoes on the thinnest crust have 187Os/188Os ratios of 0.18-0.21. Those on the thickest crust have 187Os/188Os ratios as high as 0.64. All the Os values are much too radiogenic to

  8. Occupational exposure following Yttrium-90 microspheres SIR therapy

    International Nuclear Information System (INIS)

    Fontaine, P.; Boirie, G.; Dieudonne, A.; Leguludec, D.; Lebtahi, R.; Ben Reguiga, M.

    2015-01-01

    Full text of publication follows. Introduction: Selective Internal Radiation Therapy (SIRT) is a promising technique for solid hepatic neoplasms treatment. SIRT consists in implanting radioactive microspheres (RMS) in targeted hepatic lesions via femoral artery. Two RMS-Therapsheres [glass-microspheres/TSR] and Sir-Spheres [resin-spheres/SSR]- are marketed in the European market, both radiolabeled with Yttrium-90. The objective of this study is to assess occupational exposure for nuclear medicine, radiology and clinical staff involved in Y 90 -RMS preparation and implantation. Materials and methods: The study was conducted on 20 patients treated for Hepato-Cellular Carcinoma: 10 treated with TSR and 10 with SSR. Dose rate (DR, mSv/h) or absorbed doses (mSv) measurements were made during all steps of TSR and SSR handling: sources receipt and unpacking, preparation, transport to radiology, implantation, and patient care. Measurements were made with portable ionization chamber(Babyline/Nardeux), spectrometer(FieldSpect/Aries), digital dosimeter (NED/Unfors) and operational dosimeter (Mk2/Siemens). Values were expressed as mean±SD. Results: patients received of 1.8 GBq to 3.1 GBq of TSR and 0.55 GBq to 2.4 GBq of SSR. TSR were delivered ready-to-use with the prescribed activity. For SSR only one activity was commercially available and shipped (3 GBq at calibration-time)requiring a preparation step to adjust needed activity. DR measured during RMS was 1723 ± 157 μSv/h SSR and 1189 ± 92 μSv/h for TSR. When preparing spheres in radiopharmacy, fingers and whole body doses were respectively 8326 ± 2360 μSv and 12.3 ± 5,2 μSv for Sir-Spheres vs. 33.5 ± 7.8 μSv and 1.1 ± 0.3 μSv for TSR. DR in contact with carrying case during RMS transfer to radiology were 299 ± 102 μSv/h for SSR and 5.3 ± 1.2 μSv/h for TSR. During RMS infusion, radiologist's finger doses were limited to 3.6 ± 1 μSv for SSR and 0.7± 0.3 μSv for TSR. Finally, following RMS

  9. Molybdenum Cycling During Crust Formation and Destruction

    Science.gov (United States)

    Greaney, A. T.; Rudnick, R. L.

    2016-12-01

    Molybdenum geochemistry has become an important tool for tracking the redox state of the early atmosphere and oceans as well as the emergence and sustainability of Mo-cofactored enzymes. However, in order for Mo to be enriched in the oceans, it must first be weathered out of the crust. Sulfides that weather in the presence of atmospheric O2have historically been deemed the predominant crustal source of Mo. Here, we test this assumption by determining the mineralogical hosts of Mo in Archean, Proterozoic, and Phanerozoic upper crustal rocks, using LA-ICP-MS. We also investigate Mo behavior during igneous differentiation and continental crust formation. We find that molybdenite, MoS2, is a weatherable sulfide source of Mo, but common igneous sulfides are not because their Mo concentrations are too low. However, molybdenite is uncommon in the upper continental crust. By contrast, volcanic glass is much more abundant and is a significant weatherable source of Mo that readily breaks down to release oxidized, soluble Mo whether or not atmospheric O2is present. Other common crustal mineral hosts of Mo are Ti-bearing phases like titanite, ilmenite, magnetite, and rutile that are resistant to weathering. Significant Mo depletion (relative to Ce and Pr) is observed in nearly every granitic rock analyzed in our study, but is not observed in OIB or MORB (Jenner and O'Neill, 2012). There are two possible reasons for this: 1) Mo is removed from cooling plutons during fluid expulsion, or 2) Mo is fractionated during igneous differentiation. The first scenario is a likely explanation given the solubility of oxidized Mo. However, correlations between Mo/Ce and Nb/La in several plutonic suites suggest a fractionating phase like rutile may sequester Mo in the lower crust. Additionally, a correlation between Mo/Ce and inferred tectonic setting (enrichments observed in rift-related plutons) suggest an overall tectonic influence on the availability of Mo in the upper crust.

  10. Deep Crustal Melting and the Survival of Continental Crust

    Science.gov (United States)

    Whitney, D.; Teyssier, C. P.; Rey, P. F.; Korchinski, M.

    2017-12-01

    Plate convergence involving continental lithosphere leads to crustal melting, which ultimately stabilizes the crust because it drives rapid upward flow of hot deep crust, followed by rapid cooling at shallow levels. Collision drives partial melting during crustal thickening (at 40-75 km) and/or continental subduction (at 75-100 km). These depths are not typically exceeded by crustal rocks that are exhumed in each setting because partial melting significantly decreases viscosity, facilitating upward flow of deep crust. Results from numerical models and nature indicate that deep crust moves laterally and then vertically, crystallizing at depths as shallow as 2 km. Deep crust flows en masse, without significant segregation of melt into magmatic bodies, over 10s of kms of vertical transport. This is a major mechanism by which deep crust is exhumed and is therefore a significant process of heat and mass transfer in continental evolution. The result of vertical flow of deep, partially molten crust is a migmatite dome. When lithosphere is under extension or transtension, the deep crust is solicited by faulting of the brittle upper crust, and the flow of deep crust in migmatite domes traverses nearly the entire thickness of orogenic crust in Recognition of the importance of migmatite (gneiss) domes as archives of orogenic deep crust is applicable to determining the chemical and physical properties of continental crust, as well as mechanisms and timescales of crustal differentiation.

  11. The Mafic Lower Crust of Neoproterozoic age beneath Western Arabia: Implications for Understanding African Lower Crust

    Science.gov (United States)

    Stern, R. J.; Mooney, W. D.

    2011-12-01

    We review evidence that the lower crust of Arabia - and by implication, that beneath much of Africa was formed at the same time as the upper crust, rather than being a product of Cenozoic magmatic underplating. Arabia is a recent orphan of Africa, separated by opening of the Red Sea ~20 Ma, so our understanding of its lower crust provides insights into that of Africa. Arabian Shield (exposed in W. Arabia) is mostly Neoproterozoic (880-540 Ma) reflecting a 300-million year process of continental crustal growth due to amalgamated juvenile magmatic arcs welded together by granitoid intrusions that make up as much as 50% of the Shield's surface. Seismic refraction studies of SW Arabia (Mooney et al., 1985) reveal two layers, each ~20 km thick, separated by a well-defined Conrad discontinuity. The upper crust has average Vp ~6.3 km/sec whereas the lower crust has average Vp ~7.0 km/sec, corresponding to a granitic upper crust and gabbroic lower crust. Neogene (<30 ma) lava fields in Arabia (harrats) extend over 2500 km, from Yemen to Syria. Many of these lavas contain xenoliths, providing a remarkable glimpse of the lower-crustal and upper-mantle lithosphere beneath W. Arabia. Lower crustal xenoliths brought up in 8 harrats in Saudi Arabia, Jordan, and Syria are mostly 2-pyroxene granulites of igneous (gabbroic, anorthositic, and dioritic) origin. They contain plagioclase, orthopyroxene, and clinopyroxene, and a few contain garnet and rare amphibole and yield mineral-equilibrium temperatures of 700-900°C. Pyroxene-rich and plagioclase-rich suites have mean Al2O3 contents of 13% and 19%, respectively: otherwise the two groups have similar elemental compositions, with ~50% SiO2 and ~1% TiO2, with low K2O (<0.5%) and Na2O (1-3%). Both groups show tholeiitic affinities, unrelated to their alkali basalt hosts. Mean pyroxene-rich and plagioclase-rich suites show distinct mean MgO contents (11% vs. 7%), Mg# (67 vs. 55), and contents of compatible elements Ni (169 vs. 66 ppm

  12. Lunar Quest in Second Life, Lunar Exploration Island, Phase II

    Science.gov (United States)

    Ireton, F. M.; Day, B. H.; Mitchell, B.; Hsu, B. C.

    2010-12-01

    Linden Lab’s Second Life is a virtual 3D metaverse created by users. At any one time there may be 40,000-50,000 users on line. Users develop a persona and are seen on screen as a human figure or avatar. Avatars move through Second Life by walking, flying, or teleporting. Users form communities or groups of mutual interest such as music, computer graphics, and education. These groups communicate via e-mail, voice, and text within Second Life. Information on downloading the Second Life browser and joining can be found on the Second Life website: www.secondlife.com. This poster details Phase II in the development of Lunar Exploration Island (LEI) located in Second Life. Phase I LEI highlighted NASA’s LRO/LCROSS mission. Avatars enter LEI via teleportation arriving at a hall of flight housing interactive exhibits on the LRO/ LCROSS missions including full size models of the two spacecraft and launch vehicle. Storyboards with information about the missions interpret the exhibits while links to external websites provide further information on the mission, both spacecraft’s instrument suites, and related EPO. Other lunar related activities such as My Moon and NLSI EPO programs. A special exhibit was designed for International Observe the Moon Night activities with links to websites for further information. The sim includes several sites for meetings, a conference stage to host talks, and a screen for viewing NASATV coverage of mission and other televised events. In Phase II exhibits are updated to reflect on-going lunar exploration highlights, discoveries, and future missions. A new section of LEI has been developed to showcase NASA’s Lunar Quest program. A new exhibit hall with Lunar Quest information has been designed and is being populated with Lunar Quest information, spacecraft models (LADEE is in place) and kiosks. A two stage interactive demonstration illustrates lunar phases with static and 3-D stations. As NASA’s Lunar Quest program matures further

  13. 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.

  14. 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.

  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. Petrologic Constraints on Iceland's Lower Crust

    Science.gov (United States)

    Kelley, D. F.; Leftwich, T. E.; Barton, M.

    2005-05-01

    Iceland is an area of relatively thick ocean crust that straddles the spreading MAR. Iceland was created by seafloor spreading originating about 55 Ma above abnormally hot mantle. The high temperatures resulted in greater melt volumes that enhanced crustal thickening. Geophysical investigations provide fundamental insight on crustal features, but results are contradictory. Early seismic, magneto-telluric, and resistivity studies predicted thin crust with partial melt regions at depths of 10-15 km beneath the neovolcanic zones. Reinterpretations based on recent seismic studies suggest thicker and cooler crust. These studies have shown magma lenses at shallow depths beneath volcanic centers, but cannot confirm their presence in the lower crust. Knowledge of the depth of magma chambers is critical to constrain the geothermal gradients in Icelandic crust and to resolve discrepancies in interpretation of geophysical data. Analyses of glasses in Icelandic lavas erupted from 11 volcanic centers throughout the rift zones have been compiled. The pressures of equilibration of these liquids with ol, high-Ca pyx, and plag were estimated qualitatively from projections into the pseudoternary system Ol-Di-Qtz. The results (ca. 0.6 GPa) indicate crystallization in magma chambers located at about 20 km depth. Equilibrium pressures also have been calculated quantitatively. These results (0.6±0.2 GPa) indicate magma chambers at 19.8±6.5 km depth beneath the volcanic centers. Magma chamber at these depths are located in the lower crust inferring that it must be relatively warm. Geothermal gradients have been calculated using the depths of the sourcing magma chambers and any shallow seismically detected magma chambers at each location. An average crustal composition has been calculated from the compiled geochemical data and was used to calculate density variations and seismic velocities along the geotherms. The distribution of sample locations in this study provides sufficient data

  17. Two lunar global asymmetries

    Science.gov (United States)

    Hartung, J. B.

    1984-01-01

    The Moon's center of mass is displaced from its center of figure about 2 km in a roughly earthward direction. Most maria are on the side of the Moon which faces the Earth. It is assumed that the Moon was initially spherically symmetric. The emplacement of mare basalts transfers mass which produces most of the observed center of mass displacement toward the Earth. The cause of the asymmetric distribution of lunar maria was examined. The Moon is in a spin orbit coupled relationship with the Earth and the effect of the Earth's gravity on the Moon is asymmetric. The earth-facing side of the Moon is a gravitational favored location for the extrusion of mare basalt magma in the same way that the topographically lower floor of a large impact basin is a gravitationally favored location. This asymmetric effect increases inversely with the fourth power of the Earth Moon distance. The history of the Earth-Moon system includes: formation of the Moon by accretion processes in a heliocentric orbit ner that of the Earth; a gravitational encounter with the Earth about 4 billion years ago resulting in capture of the Moon into a geocentric orbit and heating of the Moon through dissipation of energy related to tides raised during close approaches to the Earth(5) to produce mare basalt magma; and evolution of the Moon's orbit to its present position, slowly at first to accommodate more than 500 million years during which magmas were extruded.

  18. Characteristics and management options of crusting soils in a ...

    African Journals Online (AJOL)

    ... to control the crusting. The relationship between crust thickness and soil physical and chemical properties and management practices were assessed using stepwise regression analysis. Soil crusting was largely related to soil aggregation, infiltration, fine sand fraction, cotton monocropping and crop residue incorporation.

  19. Influence of substrate rocks on Fe-Mn crust composition

    Science.gov (United States)

    Hein, J.R.; Morgan, C.L.

    1999-01-01

    Principal Component and other statistical analyses of chemical and mineralogical data of Fe-Mn oxyhydroxide crusts and their underlying rock substrates in the central Pacific indicate that substrate rocks do not influence crust composition. Two ridges near Johnston Atoll were dredged repetitively and up to seven substrate rock types were recovered from small areas of similar water depths. Crusts were analyzed mineralogically and chemically for 24 elements, and substrates were analyzed mineralogically and chemically for the 10 major oxides. Compositions of crusts on phosphatized substrates are distinctly different from crusts on substrates containing no phosphorite. However, that relationship only indicates that the episodes of phosphatization that mineralized the substrate rocks also mineralized the crusts that grew on them. A two-fold increase in copper contents in crusts that grew on phosphatized clastic substrate rocks, relative to crusts on other substrate rock types, is also associated with phosphatization and must have resulted from chemical reorganization during diagenesis. Phosphatized crusts show increases in Sr, Zn, Ca, Ba, Cu, Ce, V, and Mo contents and decreases in Fe, Si, and As contents relative to non-phosphatized crusts. Our statistical results support previous studies which show that crust compositions reflect predominantly direct precipitation from seawater (hydrogenetic), and to lesser extents reflect detrital input and diagenetic replacement of parts of the older crust generation by carbonate fluorapatite.

  20. Permeability of crust is key to crispness retention

    NARCIS (Netherlands)

    Hirte, A.; Hamer, R.J.; Meinders, M.B.J.; Primo-Martin, C.

    2010-01-01

    Bread loses crispness rapidly after baking because water originating from the wet crumb accumulates in the dry crust. This water accumulation might be increased by the dense and low permeable character of the bread crust. Our objective was to investigate the influence of permeability of the crust on

  1. New Processing of Spaceborne Imaging Radar-C (SIR-C) Data

    Science.gov (United States)

    Meyer, F. J.; Gracheva, V.; Arko, S. A.; Labelle-Hamer, A. L.

    2017-12-01

    The Spaceborne Imaging Radar-C (SIR-C) was a radar system, which successfully operated on two separate shuttle missions in April and October 1994. During these two missions, a total of 143 hours of radar data were recorded. SIR-C was the first multifrequency and polarimetric spaceborne radar system, operating in dual frequency (L- and C- band) and with quad-polarization. SIR-C had a variety of different operating modes, which are innovative even from today's point of view. Depending on the mode, it was possible to acquire data with different polarizations and carrier frequency combinations. Additionally, different swaths and bandwidths could be used during the data collection and it was possible to receive data with two antennas in the along-track direction.The United States Geological Survey (USGS) distributes the synthetic aperture radar (SAR) images as single-look complex (SLC) and multi-look complex (MLC) products. Unfortunately, since June 2005 the SIR-C processor has been inoperable and not repairable. All acquired SLC and MLC images were processed with a course resolution of 100 m with the goal of generating a quick look. These images are however not well suited for scientific analysis. Only a small percentage of the acquired data has been processed as full resolution SAR images and the unprocessed high resolution data cannot be processed any more at the moment.At the Alaska Satellite Facility (ASF) a new processor was developed to process binary SIR-C data to full resolution SAR images. ASF is planning to process the entire recoverable SIR-C archive to full resolution SLCs, MLCs and high resolution geocoded image products. ASF will make these products available to the science community through their existing data archiving and distribution system.The final paper will describe the new processor and analyze the challenges of reprocessing the SIR-C data.

  2. 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.

  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. 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.

  5. Lunar power systems. Final report

    International Nuclear Information System (INIS)

    1986-12-01

    The findings of a study on the feasibility of several methods of providing electrical power for a permanently manned lunar base are provided. Two fundamentally different methods for lunar electrical power generation are considered. One is the use of a small nuclear reactor and the other is the conversion of solar energy to electricity. The baseline goal was to initially provide 300 kW of power with growth capability to one megawatt and eventually to 10 megawatts. A detailed, day by day scenario for the establishment, build-up, and operational activity of the lunar base is presented. Also presented is a conceptual approach to a supporting transportation system which identifies the number, type, and deployment of transportation vehicles required to support the base. An approach to the use of solar cells in the lunar environment was developed. There are a number of heat engines which are applicable to solar/electric conversions, and these are examined. Several approaches to energy storage which were used by the electric power utilities were examined and those which could be used at a lunar base were identified

  6. Density Sorting During the Evolution of Continental Crust

    Science.gov (United States)

    Kelemen, P. B.; Behn, M. D.; Hacker, B. R.

    2015-12-01

    We consider two settings - in addition to "delamination" of arc lower crust - in which dense, mafic eclogites founder into the convecting mantle while buoyant, felsic lithologies accumulate at the base of evolving continental crust. Arc processes play a central role in generating continental crust, but it remains uncertain how basaltic arc crust is transformed to andesitic continental crust. Dense, SiO2-poor products of fractionation may founder from the base of arc crust by "delamination", but lower arc crust after delamination has significantly different trace elements compared to lower continental crust (LCC). In an alternative model, buoyant magmatic rocks generated at arcs are first subducted, mainly via subduction erosion. Upon heating, these buoyant lithologies ascend through the mantle wedge or along a subduction channel, and are "relaminated" at
the base of overlying crust (e.g., Hacker et al EPSL 11, AREPS 15). Average buoyant lavas and plutons
for the Aleutians, Izu-Bonin-Marianas, Kohistan and Talkeetna arcs fall within the range of estimated LCC major and trace elements. Relamination is more efficient in generating continental crust than delamination. Himalayan cross-sections show Indian crust thrust beneath Tibetan crust, with no intervening mantle. There is a horizontal Moho at ca 80 km depth, extending from thickened Indian crust, across the region where Tibetan crust overlies Indian crust, into thickened Tibetan crust. About half the subducted Indian crust is present, whereas the other half is missing. Data (Vp/Vs; Miocene lavas formed by interaction of continental crust with mantle; xenolith thermometry) indicate 1000°C or more from ca 50 km depth to the Moho since the Miocene. We build on earlier studies (LePichon et al Tectonics 92, T'phys 97; Schulte-Pelkum et al Nature 05; Monsalve et al JGR 08) to advance the hypothesis that rapid growth of garnet occurs at 70-80 km and 1000°C within subducting Indian crust. Dense eclogites founder

  7. Eocene deep crust at Ama Drime, Tibet

    DEFF Research Database (Denmark)

    Kellett, Dawn; Cottle, John; Smit, Matthijs Arjen

    2014-01-01

    Granulitized eclogite-facies rocks exposed in the Ama Drime Massif, south Tibet, were dated by Lu-Hf garnet geochronology. Garnet from the three samples analyzed yielded Lu-Hf ages of 37.5 ± 0.8 Ma, 36.0 ± 1.9 Ma, and 33.9 ± 0.8 Ma. Eclogitic garnet growth is estimated at ca. 38 Ma, the oldest age...... burial and exhumation of a cold subducted slab. The rocks instead resulted from crustal thickening during the early stages of continental collision, and resided in the lower-middle crust for >20 m.y. before they were exhumed and reheated. These new data provide solid evidence for the Indian crust having...

  8. Outer crust of nonaccreting cold neutron stars

    International Nuclear Information System (INIS)

    Ruester, Stefan B.; Hempel, Matthias; Schaffner-Bielich, Juergen

    2006-01-01

    The properties of the outer crust of nonaccreting cold neutron stars are studied by using modern nuclear data and theoretical mass tables, updating in particular the classic work of Baym, Pethick, and Sutherland. Experimental data from the atomic mass table from Audi, Wapstra, and Thibault of 2003 are used and a thorough comparison of many modern theoretical nuclear models, both relativistic and nonrelativistic, is performed for the first time. In addition, the influences of pairing and deformation are investigated. State-of-the-art theoretical nuclear mass tables are compared to check their differences concerning the neutron drip line, magic neutron numbers, the equation of state, and the sequence of neutron-rich nuclei up to the drip line in the outer crust of nonaccreting cold neutron stars

  9. 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,

  10. Status and Future of Lunar Geoscience.

    Science.gov (United States)

    1986

    A review of the status, progress, and future direction of lunar research is presented in this report from the lunar geoscience working group of the National Aeronautics and Space Administration. Information is synthesized and presented in four major sections. These include: (1) an introduction (stating the reasons for lunar study and identifying…

  11. Nanophase Fe0 in lunar soils

    Indian Academy of Sciences (India)

    globules that occur in the rinds of many soil grains and in the ... tinitic glass is a quenched product of silicate melts, also produced by micrometeorite impacts on lunar soils ..... stand impact processes and their products. ... cules at night; the earth's atmosphere by con- .... deep lunar interior from an inversion of lunar free oscil-.

  12. Formation of continental crust by intrusive magmatism

    Science.gov (United States)

    Rozel, A. B.; Golabek, G. J.; Jain, C.; Tackley, P. J.; Gerya, T.

    2017-09-01

    How were the continents formed in the Earth? No global numerical simulation of our planet ever managed to generate continental material self-consistently. In the present study, we show that the latest developments of the convection code StagYY enable to estimate how to produce the early continents, more than 3 billion years ago. In our models, melting of pyrolitic rocks generates a basaltic melt and leaves behind a depleted solid residue (a harzburgite). The melt generated in the mantle is transported to the surface. Only basaltic rocks melting again can generate continental crust. Should the basaltic melt always reach the open air and cool down? Should the melt be intruded warm in the pre-existing crust? The present study shows that both processes have to be considered to produce continents. Indeed, granitoids can only be created in a tight window of pressure-temperature. If all basalt is quickly cooled by surface volcanism, the lithosphere will be too cold. If all basalt is intruded warm below the crust then the lithosphere will be too warm. The key is to have both volcanism and plutonism (intrusive magmatism) to reach the optimal temperature and form massive volumes of continental material.

  13. Lunar Cube Transfer Trajectory Options

    Science.gov (United States)

    Folta, David; Dichmann, Donald James; Clark, Pamela E.; Haapala, Amanda; Howell, Kathleen

    2015-01-01

    Numerous Earth-Moon trajectory and lunar orbit options are available for Cubesat missions. Given the limited Cubesat injection infrastructure, transfer trajectories are contingent upon the modification of an initial condition of the injected or deployed orbit. Additionally, these transfers can be restricted by the selection or designs of Cubesat subsystems such as propulsion or communication. Nonetheless, many trajectory options can b e considered which have a wide range of transfer duration, fuel requirements, and final destinations. Our investigation of potential trajectories highlights several options including deployment from low Earth orbit (LEO) geostationary transfer orbits (GTO) and higher energy direct lunar transfer and the use of longer duration Earth-Moon dynamical systems. For missions with an intended lunar orbit, much of the design process is spent optimizing a ballistic capture while other science locations such as Sun-Earth libration or heliocentric orbits may simply require a reduced Delta-V imparted at a convenient location along the trajectory.

  14. Lunar Rotation, Orientation and Science

    Science.gov (United States)

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

    2004-12-01

    The Moon is the most familiar example of the many satellites that exhibit synchronous rotation. For the Moon there is Lunar Laser Ranging measurements of tides and three-dimensional rotation variations plus supporting theoretical understanding of both effects. Compared to uniform rotation and precession the lunar rotational variations are up to 1 km, while tidal variations are about 0.1 m. Analysis of the lunar variations in pole direction and rotation about the pole gives moment of inertia differences, third-degree gravity harmonics, tidal Love number k2, tidal dissipation Q vs. frequency, dissipation at the fluid-core/solid-mantle boundary, and emerging evidence for an oblate boundary. The last two indicate a fluid core, but a solid inner core is not ruled out. Four retroreflectors provide very accurate positions on the Moon. The experience with the Moon is a starting point for exploring the tides, rotation and orientation of the other synchronous bodies of the solar system.

  15. 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.

  16. Verification of the linearity of the new SIR using sources of 64Cu and 99mTc

    International Nuclear Information System (INIS)

    Michotte, Carine

    2012-02-01

    The linearity of the new SIR electronics has been verified by looking for deviations from the exponential decay for several 64 Cu and 99m Tc sources. Data analyses are compared with the half-life used as a fixed or free parameter. It is concluded that no significant non-linearity is observed in the new SIR. For comparison, the same method has been applied to analyse existing data from the original SIR. (author)

  17. Proceedings of the 40th Lunar and Planetary Science Conference

    Science.gov (United States)

    2009-01-01

    The 40th Lunar and Planetary Science Conference included sessions on: Phoenix: Exploration of the Martian Arctic; Origin and Early Evolution of the Moon; Comet Wild 2: Mineralogy and More; Astrobiology: Meteorites, Microbes, Hydrous Habitats, and Irradiated Ices; Phoenix: Soil, Chemistry, and Habitability; Planetary Differentiation; Presolar Grains: Structures and Origins; SPECIAL SESSION: Venus Atmosphere: Venus Express and Future Missions; Mars Polar Caps: Past and Present; SPECIAL SESSION: Lunar Missions: Results from Kaguya, Chang'e-1, and Chandrayaan-1, Part I; 5 Early Nebula Processes and Models; SPECIAL SESSION: Icy Satellites of Jupiter and Saturn: Cosmic Gymnasts; Mars: Ground Ice and Climate Change; SPECIAL SESSION: Lunar Missions: Results from Kaguya, Chang'e-1, and Chandrayaan-1, Part II; Chondrite Parent-Body Processes; SPECIAL SESSION: Icy Satellites of Jupiter and Saturn: Salubrious Surfaces; SNC Meteorites; Ancient Martian Crust: Primary Mineralogy and Aqueous Alteration; SPECIAL SESSION: Messenger at Mercury: A Global Perspective on the Innermost Planet; CAIs and Chondrules: Records of Early Solar System Processes; Small Bodies: Shapes of Things to Come; Sulfur on Mars: Rocks, Soils, and Cycling Processes; Mercury: Evolution and Tectonics; Venus Geology, Volcanism, Tectonics, and Resurfacing; Asteroid-Meteorite Connections; Impacts I: Models and Experiments; Solar Wind and Genesis: Measurements and Interpretation; Mars: Aqueous Processes; Magmatic Volatiles and Eruptive Conditions of Lunar Basalts; Comparative Planetology; Interstellar Matter: Origins and Relationships; Impacts II: Craters and Ejecta Mars: Tectonics and Dynamics; Mars Analogs I: Geological; Exploring the Diversity of Lunar Lithologies with Sample Analyses and Remote Sensing; Chondrite Accretion and Early History; Science Instruments for the Mars Science Lander; . Martian Gullies: Morphology and Origins; Mars: Dunes, Dust, and Wind; Mars: Volcanism; Early Solar System Chronology

  18. Serum inflammatory markers in the elderly: are they useful in differentiating sepsis from SIRS?

    Directory of Open Access Journals (Sweden)

    Mahshid Talebi-Taher

    2014-06-01

    Full Text Available Differentiating sepsis from other noninfectious causes of systemic inflammation is often difficult in the elderly. The aim of this study was to evaluate the ability of C-reactive protein (CRP, Erythrocyte Sedimentation Rate (ESR, procalcitonin (PCT, and Interleukin-6 (IL-6 to identify elderly patients with sepsis. In this single center prospective observational study, we included all consecutive elderly patients admitted with suspected sepsis and systemic inflammatory response syndrome (SIRS in an emergency department. Blood samples for measuring CRP, PCT, IL-6, ESR and white blood cells (WBC count were taken at first day of admission. Sensitivity, specificity, positive and negative predictive values were calculated for each inflammatory markers being studied. A total of 150 elderly patients aged 65 and older, 50 with sepsis and 50 with SIRS, and fifty individuals in a normal health status were included. CRP exhibited the greatest sensitivity (98% and negative predictive value (98.6% and performed best in differentiating patients with sepsis from those with SIRS. In a receiver operating characteristic curve analysis, IL-6 performed best in distinguishing between SIRS and the control group (AUC 0.75, 95% CI. On the other hand, both CRP and ESR appeared to be a more accurate diagnostic parameter for differentiating sepsis from SIRS among elderly patients.

  19. Constitutive Relation of Engineering Material Based on SIR Model and HAM

    Directory of Open Access Journals (Sweden)

    Haoxiang He

    2014-01-01

    Full Text Available As an epidemic mathematical model, the SIR model represents the transition of the Susceptible, Infected, and Recovered. The profound implication of the SIR model is viewed as the propagation and dynamic evolutionary process of the different internal components and the characteristics in a complex system subject to external effect. The uniaxial stress-strain curve of engineering material represents the basic constitutive relation, which also represents the damage propagation in the units of the damaged member. Hence, a novel dynamic stress-strain model is established based on the SIR model. The analytical solution and the approximate solution for the proposed model are represented according to the homotopy analysis method (HAM, and the relationship of the solution and the size effect and the strain rate is discussed. In addition, an experiment on the size effect of confined concrete is carried out and the solution of SIR model is suitable for simulation. The results show that the mechanical mechanism of the parameters of the uniaxial stress-strain model proposed in this paper reflects the actual characteristics of the materials. The solution of the SIR model can fully and accurately show the change of the mechanical performance and the influence of the size effect and the strain rate.

  20. SIRS score on admission and initial concentration of IL-6 as severe acute pancreatitis outcome predictors.

    Science.gov (United States)

    Gregoric, Pavle; Pavle, Gregoric; Sijacki, Ana; Ana, Sijacki; Stankovic, Sanja; Sanja, Stankovic; Radenkovic, Dejan; Dejan, Radenkovic; Ivancevic, Nenad; Nenad, Ivancevic; Karamarkovic, Aleksandar; Aleksandar, Karamarkovic; Popovic, Nada; Nada, Popovic; Karadzic, Borivoje; Borivoje, Karadzic; Stijak, Lazar; Stefanovic, Branislav; Branislav, Stefanovic; Milosevic, Zoran; Zoran, Milosević; Bajec, Djordje; Djordje, Bajec

    2010-01-01

    Early recognition of severe form of acute pancreatitis is important because these patients need more agressive diagnostic and therapeutical approach an can develope systemic complications such as: sepsis, coagulopathy, Acute Lung Injury (ALI), Acute Respiratory Distress Syndrome (ARDS), Multiple Organ Dysfunction Syndrome (MODS), Multiple Organ Failure (MOF). To determine role of the combination of Systemic Inflammatory Response Syndrome (SIRS) score and serum Interleukin-6 (IL-6) level on admission as predictor of illness severity and outcome of Severe Acute Pancreatitis (SAP). We evaluated 234 patients with first onset of SAP appears in last twenty four hours. A total of 77 (33%) patients died. SIRS score and serum IL-6 concentration were measured in first hour after admission. In 105 patients with SIRS score 3 and higher, initial measured IL-6 levels were significantly higher than in the group of remaining 129 patients (72 +/- 67 pg/mL, vs 18 +/- 15 pg/mL). All nonsurvivals were in the first group, with SIRS score 3 and 4 and initial IL-6 concentration 113 +/- 27 pg/mL. The values of C-reactive Protein (CRP) measured after 48h, Acute Physiology and Chronic Health Evaluation (APACHE II) score on admission and Ranson score showed the similar correlation, but serum amylase level did not correlate significantly with Ranson score, IL-6 concentration and APACHE II score. The combination of SIRS score on admission and IL-6 serum concentration can be early, predictor of illness severity and outcome in SAP.

  1. Lunar Base Heat Pump

    Science.gov (United States)

    Walker, D.; Fischbach, D.; Tetreault, R.

    1996-01-01

    The objective of this project was to investigate the feasibility of constructing a heat pump suitable for use as a heat rejection device in applications such as a lunar base. In this situation, direct heat rejection through the use of radiators is not possible at a temperature suitable for lde support systems. Initial analysis of a heat pump of this type called for a temperature lift of approximately 378 deg. K, which is considerably higher than is commonly called for in HVAC and refrigeration applications where heat pumps are most often employed. Also because of the variation of the rejection temperature (from 100 to 381 deg. K), extreme flexibility in the configuration and operation of the heat pump is required. A three-stage compression cycle using a refrigerant such as CFC-11 or HCFC-123 was formulated with operation possible with one, two or three stages of compression. Also, to meet the redundancy requirements, compression was divided up over multiple compressors in each stage. A control scheme was devised that allowed these multiple compressors to be operated as required so that the heat pump could perform with variable heat loads and rejection conditions. A prototype heat pump was designed and constructed to investigate the key elements of the high-lift heat pump concept. Control software was written and implemented in the prototype to allow fully automatic operation. The heat pump was capable of operation over a wide range of rejection temperatures and cooling loads, while maintaining cooling water temperature well within the required specification of 40 deg. C +/- 1.7 deg. C. This performance was verified through testing.

  2. 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

  3. SirT1—A Sensor for Monitoring Self-Renewal and Aging Process in Retinal Stem Cells

    Directory of Open Access Journals (Sweden)

    Chi-Hsien Peng

    2010-06-01

    Full Text Available Retinal stem cells bear potency of proliferation, self-renewal, and differentiation into many retinal cells. Utilizing appropriate sensors one can effectively detect the self-renewal and aging process abilities. Silencing information regulator (SirT1, a member of the sirtuin family, is a NAD-dependent histone deacetylase and an essential mediator for longevity in normal cells by calorie restriction. We firstly investigate the SirT1 mRNA expression in retinal stem cells from rats and 19 human eyes of different ages. Results revealed that SirT1 expression was significantly decreased in in vivo aged eyes, associated with poor self-renewal abilities. Additionally, SirT1 mRNA levels were dose-dependently increased in resveratrol- treated retinal stem cells. The expression of SirT1 on oxidative stress-induced damage was significantly decreased, negatively correlated with the level of intracellular reactive oxygen species production. Treatment with resveratrol could effectively further reduce oxidative stress induced by H2O2 treatment in retinal stem cells. Importantly, the anti-oxidant effects of resveratrol in H2O2-treated retinal stem cells were significantly abolished by knockdown of SirT1 expression (sh-SirT1. SirT1 expression provides a feasible sensor in assessing self-renewal and aging process in retinal stem cells. Resveratrol can prevent reactive oxygen species-induced damages via increased retinal SirT1 expression.

  4. Uses for lunar crawler transporters

    Science.gov (United States)

    Kaden, Richard A.

    This article discusses state-of-the-art crawler transporters and expresses the need for additional research and development for lunar crawlers. The thrust of the paper illustrates how the basic crawler technology has progressed to a point where extremely large modules can be shop fabricated and move to some distant location at a considerable savings. Also, extremely heavy loads may be lifted by large crawler cranes and placed in designed locations. The Transi-Lift Crawler crane with its traveling counterweight is an attractive concept for lunar construction.

  5. Building lunar roads - An overview

    Science.gov (United States)

    Rutledge, Bennett

    The problems involved in constructing lunar roads are explored. The main challenges are airlessness, low gravity, and solar effects, especially temperature extremes. Also involved are the expense of delivering equipment and material to the job site (especially for bridges and other structures), obtaining skilled labor, and providing maintenance. The lunar road will most likely be gravel, but with the size of the material closer to cobblestone to reduce scattering. They will probably be very winding, even on the flats, and feature numerous bridges and some cuts. This traffic will be mostly automatic or teleoperated cargo carriers with a handful of shirtsleeve-pressurized 'passenger cars' large enough to live in for several days.

  6. Mg-spinel lithology: A new rock type on the lunar farside

    Science.gov (United States)

    Pieters, C.M.; Besse, S.; Boardman, J.; Buratti, B.; Cheek, L.; Clark, R.N.; Combe, J.-P.; Dhingra, D.; Goswami, J.N.; Green, R.O.; Head, J.W.; Isaacson, P.; Klima, R.; Kramer, G.; Lundeen, S.; Malaret, E.; McCord, T.; Mustard, J.; Nettles, J.; Petro, N.; Runyon, C.; Staid, M.; Sunshine, J.; Taylor, L.A.; Thaisen, K.; Tompkins, S.; Whitten, J.

    2011-01-01

    High-resolution compositional data from Moon Mineralogy Mapper (M 3) for the Moscoviense region on the lunar farside reveal three unusual, but distinctive, rock types along the inner basin ring. These are designated "OOS" since they are dominated by high concentrations of orthopyroxene, olivine, and Mg-rich spinel, respectively. The OOS occur as small areas, each a few kilometers in size, that are widely separated within the highly feldspathic setting of the basin rim. Although the abundance of plagioclase is not well constrained within the OOS, the mafic mineral content is exceptionally high, and two of the rock types could approach pyroxenite and harzburgite in composition. The third is a new rock type identified on the Moon that is dominated by Mg-rich spinel with no other mafic minerals detectable (lunar crust; they may thus be near contemporaneous with crustal products from the cooling magma ocean. Copyright ?? 2011 by the American Geophysical Union.

  7. Iron Abundances in Lunar Impact Basin Melt Sheets From Orbital Magnetic Field Data

    Science.gov (United States)

    Oliveira, Joana S.; Wieczorek, Mark A.; Kletetschka, Gunther

    2017-12-01

    Magnetic field data acquired from orbit shows that the Moon possesses many magnetic anomalies. Though most of these are not associated with known geologic structures, some are found within large impact basins within the interior peak ring. The primary magnetic carrier in lunar rocks is metallic iron, but indigenous lunar rocks are metal poor and cannot account easily for the observed field strengths. The projectiles that formed the largest impact basins must have contained a significant quantity of metallic iron, and a portion of this iron would have been retained on the Moon's surface within the impact melt sheet. Here we use orbital magnetic field data to invert for the magnetization within large impact basins using the assumption that the crust is unidirectionally magnetized. We develop a technique based on laboratory thermoremanent magnetization acquisition to quantify the relationship between the strength of the magnetic field at the time the rock cooled and the abundance of metal in the rock. If we assume that the magnetized portion of the impact melt sheet is 1 km thick, we find average abundances of metallic iron ranging from 0.11% to 0.45 wt %, with an uncertainty of a factor of about 3. This abundance is consistent with the metallic iron abundances in sampled lunar impact melts and the abundance of projectile contamination in terrestrial impact melts. These results help constrain the composition of the projectile, the impact process, and the time evolution of the lunar dynamo.

  8. Lunar phases and crisis center telephone calls.

    Science.gov (United States)

    Wilson, J E; Tobacyk, J J

    1990-02-01

    The lunar hypothesis, that is, the notion that lunar phases can directly affect human behavior, was tested by time-series analysis of 4,575 crisis center telephone calls (all calls recorded for a 6-month interval). As expected, the lunar hypothesis was not supported. The 28-day lunar cycle accounted for less than 1% of the variance of the frequency of crisis center calls. Also, as hypothesized from an attribution theory framework, crisis center workers reported significantly greater belief in lunar effects than a non-crisis-center-worker comparison group.

  9. What is a lunar standstill III?

    Directory of Open Access Journals (Sweden)

    Lionel Duke Sims

    2016-12-01

    Full Text Available Prehistoric monument alignments on lunar standstills are currently understood for horizon range, perturbation event, crossover event, eclipse prediction, solstice full Moon and the solarisation of the dark Moon. The first five models are found to fail the criteria of archaeoastronomy field methods. The final model of lunar-solar conflation draws upon all the observed components of lunar standstills – solarised reverse phased sidereal Moons culminating in solstice dark Moons in a roughly nine-year alternating cycle between major and minor standstills. This lunar-solar conflation model is a syncretic overlay upon an antecedent Palaeolithic template for lunar scheduled rituals and amenable to transformation.

  10. Lunar heat flow: Regional prospective of the Apollo landing sites

    Science.gov (United States)

    Siegler, M. A.; Smrekar, S. E.

    2014-01-01

    reexamine the Apollo Heat Flow Experiment in light of new orbital data. Using three-dimensional thermal conduction models, we examine effects of crustal thickness, density, and radiogenic abundance on measured heat flow values at the Apollo 15 and 17 sites. These models show the importance of regional context on heat flux measurements. We find that measured heat flux can be greatly altered by deep subsurface radiogenic content and crustal density. However, total crustal thickness and the presence of a near-surface radiogenic-rich ejecta provide less leverage, representing only minor (<1.5 mW m-2) perturbations on surface heat flux. Using models of the crust implied by Gravity Recovery and Interior Laboratory results, we found that a roughly 9-13 mW m-2 mantle heat flux best approximate the observed heat flux. This equates to a total mantle heat production of 2.8-4.1 × 1011 W. These heat flow values could imply that the lunar interior is slightly less radiogenic than the Earth's mantle, perhaps implying that a considerable fraction of terrestrial mantle material was incorporated at the time of formation. These results may also imply that heat flux at the crust-mantle boundary beneath the Procellarum potassium, rare earth element, and phosphorus (KREEP) Terrane (PKT) is anomalously elevated compared to the rest of the Moon. These results also suggest that a limited KREEP-rich layer exists beneath the PKT crust. If a subcrustal KREEP-rich layer extends below the Apollo 17 landing site, required mantle heat flux can drop to roughly 7 mW m-2, underlining the need for future heat flux measurements outside of the radiogenic-rich PKT region.

  11. Using Lunar Impact Basin Relaxation to Test Impact Flux Models

    Science.gov (United States)

    Nimmo, F.; Conrad, J. W.; Neumann, G. A.; Kamata, S.; Fassett, C.

    2017-12-01

    Gravity data obtained by the GRAIL mission [1] has constrained the number and distribution of lunar impact basins [2]. We analyzed crater densities for newly-proposed basins to assign relative ages. The extent to which a basin is relaxed is calculated using GRAIL-derived crustal thickness models [3] by comparing the mantle uplift under basins to the surrounding region. With our catalog we can investigate the distribution of basin properties through relative time. We identify a relaxation state transition (RT) around the pre-Nectarian 4 relative age group for basins with diameters > 450 km, similar to previous results using a pre-GRAIL basin catalog [4]. This RT likely signals a change in the global thermal state of the crust, representing the time at which the lunar moho temperature fell below 1400 K [4]. This transition happens 50-100 million years (Myr) after the lunar magma ocean (LMO) solidifies [4]. Based on models and inferences of LMO solidification [5, 6] the RT is expected to occur at 4.25-4.50 Ga, depending on the rate of cooling once a crustal lid has formed [5] and the amount of tidal heating in the early crust [6]. Monotonically declining impact flux models, such as [7] and [8] predict a younger RT; 4.07-4.08 and 4.24-4.27 Ga respectively. A scaled-down version of [8] can fit the RT but fails to match the observed number of younger, unrelaxed basins. Models that invoke a later transient increase in impact flux can reproduce the inferred RT time; for instance, the model of [9] gives a RT age of 4.43-4.46 Ga. This model matches the number of younger basins and implies that basin preservation started at 4.49 Ga, likely before the LMO completely solidified. [1] Zuber M.T. et al. (2013) Science, 339, 668-671. [2] Neumann G.A. et al. (2015) Science Advances, 1, e1500852. [3] Wieczorek M.A. (2013) Science, 339, 671-675. [4] Kamata S. et al. (2015) Icarus, 250, 492-504. [5] Elkins-Tanton L.T. et al. (2011) Earth Planet. Sci. Lett., 304, 326-336. [6] Meyer, J

  12. BOREAS RSS-15 SIR-C and Landsat TM Biomass and Landcover Maps of the NSA

    Science.gov (United States)

    Hall, Forrest G. (Editor); Nickeson, Jaime (Editor); Ranson, K. Jon

    2000-01-01

    As part of BOREAS, the RSS-15 team conducted an investigation using SIR-C, X-SAR, and Landsat TM data for estimating total above-ground dry biomass for the SSA and NSA modeling grids and component biomass for the SSA. Relationships of backscatter to total biomass and total biomass to foliage, branch, and bole biomass were used to estimate biomass density across the landscape. The procedure involved image classification with SAR and Landsat TM data and development of simple mapping techniques using combinations of SAR channels. For the SSA, the SIR-C data used were acquired on 06-Oct-1994, and the Landsat TM data used were acquired on 02-Sep-1995. The maps of the NSA were developed from SIR-C data acquired on 13-Apr-1994. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

  13. Mechanical properties of lunar regolith and lunar soil simulant

    Science.gov (United States)

    Perkins, Steven W.

    1989-01-01

    Through the Surveyor 3 and 7, and Apollo 11-17 missions a knowledge of the mechanical properties of Lunar regolith were gained. These properties, including material cohesion, friction, in-situ density, grain-size distribution and shape, and porosity, were determined by indirect means of trenching, penetration, and vane shear testing. Several of these properties were shown to be significantly different from those of terrestrial soils, such as an interlocking cohesion and tensile strength formed in the absence of moisture and particle cementation. To characterize the strength and deformation properties of Lunar regolith experiments have been conducted on a lunar soil simulant at various initial densities, fabric arrangements, and composition. These experiments included conventional triaxial compression and extension, direct tension, and combined tension-shear. Experiments have been conducted at low levels of effective confining stress. External conditions such as membrane induced confining stresses, end platten friction and material self weight have been shown to have a dramatic effect on the strength properties at low levels of confining stress. The solution has been to treat these external conditions and the specimen as a full-fledged boundary value problem rather than the idealized elemental cube of mechanics. Centrifuge modeling allows for the study of Lunar soil-structure interaction problems. In recent years centrifuge modeling has become an important tool for modeling processes that are dominated by gravity and for verifying analysis procedures and studying deformation and failure modes. Centrifuge modeling is well established for terrestrial enginering and applies equally as well to Lunar engineering. A brief review of the experiments is presented in graphic and outline form.

  14. A Tale of Two Earths: Reconciling the Lunar and Terrestrial Hadean Records

    OpenAIRE

    Boehnke, Patrick

    2016-01-01

    Studying early Earth history is complicated by the fact that the rock record doesn’t extend past 4 Ga and our only record for the Hadean (>4 Ga) comes to us from detrital zircons from the Jack Hills in Western Australia. The Hadean zircon record extends back to almost 4.4 Ga and has revealed that the early Earth may have had liquid water, a felsic crust, plate boundary interactions, and possibly a biosphere. On the other hand, analyses of lunar and meteoritic samples are used to argue for a...

  15. Comparison of QSOFA score and SIRS criteria as screening mechanisms for emergency department sepsis.

    Science.gov (United States)

    Haydar, Samir; Spanier, Matthew; Weems, Patricia; Wood, Samantha; Strout, Tania

    2017-11-01

    The Quick Sequential [Sepsis-related] Organ Failure Assessment (qSOFA) score has been shown to accurately predict mortality in septic patients and is part of recently proposed diagnostic criteria for sepsis. We sought to ascertain the sensitive of the score in diagnosing sepsis, as well as the diagnostic timeliness of the score when compared to traditional systemic inflammatory response syndrome (SIRS) criteria in a population of emergency department (ED) patients treated in the ED, admitted, and subsequently discharged with a diagnosis of sepsis. Electronic health records of 200 patients who were treated for suspected sepsis in our ED and ultimately discharged from our hospital with a diagnosis of sepsis were randomly selected for review from a population of adult ED patients (N=1880). Data extracted included the presence of SIRS criteria and the qSOFA score as well as time required to meet said criteria. In this cohort, 94.5% met SIRS criteria while in the ED whereas only 58.3% met qSOFA. The mean time from arrival to SIRS documentation was 47.1min (95% CI: 36.5-57.8) compared to 84.0min (95% CI: 62.2-105.8) for qSOFA. The median ED "door" to positive SIRS criteria was 12min and 29min for qSOFA. Although qSOFA may be valuable in predicting sepsis-related mortality, it performed poorly as a screening tool for identifying sepsis in the ED. As the time to meet qSOFA criteria was significantly longer than for SIRS, relying on qSOFA alone may delay initiation of evidence-based interventions known to improve sepsis-related outcomes. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. 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

  17. Concept of Lunar Energy Park

    Science.gov (United States)

    Niino, Masayuki; Kisara, Katsuto; Chen, Lidong

    1993-10-01

    This paper presents a new concept of energy supply system named Lunar Energy Park (LEP) as one of the next-generation clean energy sources. In this concept, electricity is generated by nuclear power plants built on the moon and then transmitted to receiving stations on the earth by laser beam through transporting systems situated in geostationary orbit. The lunar nuclear power plants use a high-efficiency composite energy conversion system consisting of thermionic and thermoelectric generators to change nuclear thermal energy into electricity directly. The nuclear resources are considered to be available from the moon, and nuclear fuel transport from earth to moon is not necessary. Because direct energy conversion systems are employed, the lunar nuclear plants can be operated and controlled by robots and are maintenance-free, and so will cause no pollution to humans. The key technologies for LEP include improvements of conversion efficiency of both thermionic and thermoelectric converters, and developments of laser-beam power transmission technology as well. The details, including the construction of lunar nuclear plants, energy conversion and energy transmission systems, as well as the research plan strategies for this concept are reviewed.

  18. Lunar and Planetary Science XXXII

    Science.gov (United States)

    2001-01-01

    This CD-ROM publication contains the extended abstracts that were accepted for presentation at the 32nd Lunar and Planetary Science Conference held at Houston, TX, March 12-16, 2001. The papers are presented in PDF format and are indexed by author, keyword, meteorite, program and samples for quick reference.

  19. Delineation of major geologic structures in Turkey using SIR-B data

    Science.gov (United States)

    Toksoz, M. N.; Pettengill, G. H.; Ford, P.; Gulen, L.

    1984-01-01

    Shuttle Imaging Radar-B (SIR-B) images of well mapped segments of major faults, such as the North Anatolian Fault (NAF) and East Anatolian Fault (EAF) will be studied to identify the prominent signatures that characterize the fault zones for those specific regions. The information will be used to delineate the unmapped fault zones in areas with similar geological and geomorphological properties. The data obtained from SIR-B images will be compared and correlated with the LANDSAT thematic mapper and seismicity alignments based on well constrained earthquake epicenters.

  20. 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

  1. 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

  2. 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.

  3. Assessing the shock state of the lunar highlands: Implications for the petrogenesis and chronology of crustal anorthosites.

    Science.gov (United States)

    Pernet-Fisher, J F; Joy, K H; Martin, D J P; Donaldson Hanna, K L

    2017-07-19

    Our understanding of the formation and evolution of the primary lunar crust is based on geochemical systematics from the lunar ferroan anorthosite (FAN) suite. Recently, much effort has been made to understand this suite's petrologic history to constrain the timing of crystallisation and to interpret FAN chemical diversity. We investigate the shock histories of lunar anorthosites by combining Optical Microscope (OM) 'cold' cathodoluminescence (CL)-imaging and Fourier Transform Infrared (FTIR) spectroscopy analyses. In the first combined study of its kind, this study demonstrates that over ~4.5 Ga of impact processing, plagioclase is on average weakly shocked (30 GPa; maskelynite) are uncommon. To investigate how plagioclase trace-element systematics are affected by moderate to weak shock (~5 to 30 GPa) we couple REE+Y abundances with FTIR analyses for FAN clasts from lunar meteorite Northwest Africa (NWA) 2995. We observe weak correlations between plagioclase shock state and some REE+Y systematics (e.g., La/Y and Sm/Nd ratios). This observation could prove significant to our understanding of how crystallisation ages are evaluated (e.g., plagioclase-whole rock Sm-Nd isochrons) and for what trace-elements can be used to differentiate between lunar lithologies and assess magma source compositional differences.

  4. 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

  5. Report from International Lunar Exploration Working Group (ILEWG) to COSPAR

    Science.gov (United States)

    Foing, Bernard H.

    We refer to COSPAR and ILEWG ICEUM and lunar conferences and declarations [1-18]. We discuss how lunar missions SMART-1, Kaguya, Chang'E1&2, Chandrayaan-1, LCROSS, LRO, GRAIL, LADEE, Chang'E3 and upcoming missions contribute to lunar exploration objectives & roadmap. We present the GLUC/ICEUM11 declaration and give a report on ongoing relevant ILEWG community activities, with focus on: “1. Science and exploration - World-wide access to raw and derived (geophysical units) data products using consistent formats and coordinate systems will maximize return on investment. We call to develop and implement plans for generation, validation, and release of these data products. Data should be made available for scientific analysis and supporting the development and planning of future missions - There are still Outstanding Questions: Structure and composition of crust, mantle, and core and implications for the origin and evolution of the Earth-Moon system; Timing, origin, and consequences of late heavy bombardment; Impact processes and regolith evolution; Nature and origin of volatile emplacement; Implications for resource utilization. These questions require international cooperation and sharing of results in order to be answered in a cost-effective manner - Ground truth information on the lunar far side is missing and needed to address many important scientific questions, e.g. with a sample return from South Pole-Aitken Basin - Knowledge of the interior is poor relative to the surface, and is needed to address a number of key questions, e.g. with International Lunar Network for seismometry and other geophysical measurements - Lunar missions will be driven by exploration, resource utilization, and science; we should consider minimum science payload for every mission, e.g., landers and rovers should carry instruments to determine surface composition and mineralogy - It is felt important to have a shared database about previous missions available for free, so as to provide

  6. Lunar remote sensing and measurements

    Science.gov (United States)

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

    1980-01-01

    Remote sensing and measurements of the Moon from Apollo orbiting spacecraft and Earth form a basis for extrapolation of Apollo surface data to regions of the Moon where manned and unmanned spacecraft have not been and may be used to discover target regions for future lunar exploration which will produce the highest scientific yields. Orbital remote sensing and measurements discussed include (1) relative ages and inferred absolute ages, (2) gravity, (3) magnetism, (4) chemical composition, and (5) reflection of radar waves (bistatic). Earth-based remote sensing and measurements discussed include (1) reflection of sunlight, (2) reflection and scattering of radar waves, and (3) infrared eclipse temperatures. Photographs from the Apollo missions, Lunar Orbiters, and other sources provide a fundamental source of data on the geology and topography of the Moon and a basis for comparing, correlating, and testing the remote sensing and measurements. Relative ages obtained from crater statistics and then empirically correlated with absolute ages indicate that significant lunar volcanism continued to 2.5 b.y. (billion years) ago-some 600 m.y. (million years) after the youngest volcanic rocks sampled by Apollo-and that intensive bombardment of the Moon occurred in the interval of 3.84 to 3.9 b.y. ago. Estimated fluxes of crater-producing objects during the last 50 m.y. agree fairly well with fluxes measured by the Apollo passive seismic stations. Gravity measurements obtained by observing orbiting spacecraft reveal that mare basins have mass concentrations and that the volume of material ejected from the Orientale basin is near 2 to 5 million km 3 depending on whether there has or has not been isostatic compensation, little or none of which has occurred since 3.84 b.y. ago. Isostatic compensation may have occurred in some of the old large lunar basins, but more data are needed to prove it. Steady fields of remanent magnetism were detected by the Apollo 15 and 16 subsatellites

  7. Growth of the continental crust: a planetary-mantle perspective

    International Nuclear Information System (INIS)

    Warren, P.H.

    1988-01-01

    The lack of earth rocks older than about 3.8 Ga is frequently interpreted as evidence that the earth formed little or no subduction-resistant continental crust during the first 700 My of its history. Such models obviously imply that the pre-3.8 Ga earth was covered entirely or almost entirely by smoothly subducting oceanic crust. On the other hand, the thermal regime of the early earth probably tended to cause the oceanic crust at this time to be comparatively thin and comparatively mafic. The present earth is covered by about 50 percent oceanic crust, averaging about 7 km in thickness, and 41 percent continental crust, averaging roughly 40 km in thickness. Thus continentless-early-earth models would seem to imply a total mass of crust less than 1/3 that of the present day earth. Possible explanations are examined

  8. Kinetics of the crust thickness development of bread during baking.

    Science.gov (United States)

    Soleimani Pour-Damanab, Alireza; Jafary, A; Rafiee, Sh

    2014-11-01

    The development of crust thickness of bread during baking is an important aspect of bread quality and shelf-life. Computer vision system was used for measuring the crust thickness via colorimetric properties of bread surface during baking process. Crust thickness had a negative and positive relationship with Lightness (L (*) ) and total color change (E (*) ) of bread surface, respectively. A linear negative trend was found between crust thickness and moisture ratio of bread samples. A simple mathematical model was proposed to predict the development of crust thickness of bread during baking, where the crust thickness was depended on moisture ratio that was described by the Page moisture losing model. The independent variables of the model were baking conditions, i.e. oven temperature and air velocity, and baking time. Consequently, the proposed model had well prediction ability, as the mean absolute estimation error of the model was 7.93 %.

  9. 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

  10. The Lunar Magma Ocean (LMO) Paradigm Versus the Realities of Lunar Anorthosites

    Science.gov (United States)

    Treiman, A. H.; Gross, J.

    2018-05-01

    The paradigm of the Lunar Magma Ocean (LMO) is inconsistent with much chemical and compositional data on lunar anorthosites. The paradigm of serial anorthosite diapirism is more consistent, though not a panacea.

  11. Threshold Dynamics of a Stochastic SIR Model with Vertical Transmission and Vaccination

    OpenAIRE

    Miao, Anqi; Zhang, Jian; Zhang, Tongqian; Pradeep, B. G. Sampath Aruna

    2017-01-01

    A stochastic SIR model with vertical transmission and vaccination is proposed and investigated in this paper. The threshold dynamics are explored when the noise is small. The conditions for the extinction or persistence of infectious diseases are deduced. Our results show that large noise can lead to the extinction of infectious diseases which is conducive to epidemic diseases control.

  12. The Threshold of a Stochastic SIRS Model with Vertical Transmission and Saturated Incidence

    Directory of Open Access Journals (Sweden)

    Chunjuan Zhu

    2017-01-01

    Full Text Available The threshold of a stochastic SIRS model with vertical transmission and saturated incidence is investigated. If the noise is small, it is shown that the threshold of the stochastic system determines the extinction and persistence of the epidemic. In addition, we find that if the noise is large, the epidemic still prevails. Finally, numerical simulations are given to illustrate the results.

  13. Threshold Dynamics of a Stochastic SIR Model with Vertical Transmission and Vaccination

    Directory of Open Access Journals (Sweden)

    Anqi Miao

    2017-01-01

    Full Text Available A stochastic SIR model with vertical transmission and vaccination is proposed and investigated in this paper. The threshold dynamics are explored when the noise is small. The conditions for the extinction or persistence of infectious diseases are deduced. Our results show that large noise can lead to the extinction of infectious diseases which is conducive to epidemic diseases control.

  14. Lyapunov functions and global stability for SIR and SEIR models with age-dependent susceptibility

    KAUST Repository

    Korobeinikov, Andrei; Melnik, Andrey V.

    2013-01-01

    We consider global asymptotic properties for the SIR and SEIR age structured models for infectious diseases where the susceptibility depends on the age. Using the direct Lyapunov method with Volterra type Lyapunov functions, we establish conditions for the global stability of a unique endemic steady state and the infection-free steady state.

  15. A Possible Source For Sir Thomas More’s ‘Mountainish Inhumanity’

    NARCIS (Netherlands)

    Steenbergh, Kristine

    2017-01-01

    Shakespeare’s authorship of a scene in Sir Thomas More has been established as highly probable on the basis of an analysis of the handwriting, vocabulary, and collocations stylistics. His addition to the play was long believed to have been written soon after publication of the original play, in

  16. Mammalian Sir2 homolog SIRT3 regulates global mitochondrial lysine acetylation

    DEFF Research Database (Denmark)

    Lombard, David B; Alt, Frederick W; Cheng, Hwei-Ling

    2007-01-01

    Homologs of the Saccharomyces cerevisiae Sir2 protein, sirtuins, promote longevity in many organisms. Studies of the sirtuin SIRT3 have so far been limited to cell culture systems. Here, we investigate the localization and function of SIRT3 in vivo. We show that endogenous mouse SIRT3 is a solubl...

  17. Application of Homotopy Perturbation and Variational Iteration Methods to SIR Epidemic Model

    DEFF Research Database (Denmark)

    Ghotbi, Abdoul R.; Barari, Amin; Omidvar, M.

    2011-01-01

    effective strategy against childhood diseases, the development of the framework that would predict the optimal vaccine coverage level needed to prevent the spread of diseases is crucial. The SIR model is a standard compartmental model that has been used to describe many epidemiological diseases...

  18. 90Sr content in 90Y-labeled SIR-spheres and Zevalin.

    Science.gov (United States)

    Metyko, John; Erwin, William; Poston, John; Jimenez, Sandra

    2014-11-01

    Three different 90Y internally administered radionuclide therapies are currently used in both standard-of-care and clinical trial procedures atMD Anderson Cancer Center. TheraSphere and SIR-Spheres therapies utilize 90Y-labeled microspheres, while Zevalin is an 90Y-labeled radioimmunotherapeutic agent. Several publications have indicated radionuclidic impurities resulting from 90Y production methods. The 90Y in SIR-Spheres and Zevalin are produced from a 90Sr/90Y generator, which leaves measurable quantities of 90Sr in the final product. TheraSphere 90Y is produced in a nuclear reactor which results in a large number of impurities, most notably 88Y and 91Y. Product information sheets reference these impurities with specific limits given. These limits represent a tiny fraction of the total product activity, and in the case of TheraSphere and SIR-Spheres gamma-emitting impurities, this has been verified in the literature. An analysis of 90Sr impurities in SIR-Spheres and Zevalin is presented in this paper. Impurity quantities were found to be within the vendors’ documented limits.

  19. Geologic Mapping of the Lunar South Pole, Quadrangle LQ-30: Volcanic History and Stratigraphy of Schroedinger Basin

    Science.gov (United States)

    Mest, S. C.; Berman, D. C.; Petro, N. E.

    2009-01-01

    In this study we use recent images and topographic data to map the geology and geomorphology of the lunar South Pole quadrangle (LQ-30) at 1:2.5M scale [1-4] in accordance with the Lunar Geologic Mapping Program. Mapping of LQ-30 began during Mest's postdoctoral appointment and has continued under the PG&G Program, from which funding became available in February 2009. Preliminary map-ping and analyses have been done using base materials compiled by Mest, but properly mosaicked and spatially registered base materials are being compiled by the USGS and should be received by the end of June 2009. The overall objective of this research is to constrain the geologic evolution of the lunar South Pole (LQ-30: 60deg -90deg S, 0deg - +/-180deg ) with specific emphasis on evaluation of a) the regional effects of basin formation on the structure and composition of the crust and b) the spatial distribution of ejecta, in particular resulting from formation of the South Pole-Aitken (SPA) basin and other large basins. Key scientific objectives include: 1) Constraining the geologic history of the lunar South Pole and examining the spatial and temporal variability of geologic processes within the map area. 2) Constraining the vertical and lateral structure of the lunar regolith and crust, assessing the distribution of impact-generated materials, and determining the timing and effects of major basin-forming impacts on crustal structure and stratigraphy in the map area. And 3) assessing the distribution of resources (e.g., H, Fe, Th) and their relationships with surface materials.

  20. C. elegans SIRT6/7 homolog SIR-2.4 promotes DAF-16 relocalization and function during stress.

    Science.gov (United States)

    Chiang, Wei-Chung; Tishkoff, Daniel X; Yang, Bo; Wilson-Grady, Joshua; Yu, Xiaokun; Mazer, Travis; Eckersdorff, Mark; Gygi, Steven P; Lombard, David B; Hsu, Ao-Lin

    2012-09-01

    FoxO transcription factors and sirtuin family deacetylases regulate diverse biological processes, including stress responses and longevity. Here we show that the Caenorhabditis elegans sirtuin SIR-2.4--homolog of mammalian SIRT6 and SIRT7 proteins--promotes DAF-16-dependent transcription and stress-induced DAF-16 nuclear localization. SIR-2.4 is required for resistance to multiple stressors: heat shock, oxidative insult, and proteotoxicity. By contrast, SIR-2.4 is largely dispensable for DAF-16 nuclear localization and function in response to reduced insulin/IGF-1-like signaling. Although acetylation is known to regulate localization and activity of mammalian FoxO proteins, this modification has not been previously described on DAF-16. We find that DAF-16 is hyperacetylated in sir-2.4 mutants. Conversely, DAF-16 is acetylated by the acetyltransferase CBP-1, and DAF-16 is hypoacetylated and constitutively nuclear in response to cbp-1 inhibition. Surprisingly, a SIR-2.4 catalytic mutant efficiently rescues the DAF-16 localization defect in sir-2.4 null animals. Acetylation of DAF-16 by CBP-1 in vitro is inhibited by either wild-type or mutant SIR-2.4, suggesting that SIR-2.4 regulates DAF-16 acetylation indirectly, by preventing CBP-1-mediated acetylation under stress conditions. Taken together, our results identify SIR-2.4 as a critical regulator of DAF-16 specifically in the context of stress responses. Furthermore, they reveal a novel role for acetylation, modulated by the antagonistic activities of CBP-1 and SIR-2.4, in modulating DAF-16 localization and function.

  1. Crust formation and its effect on the molten pool coolability

    Energy Technology Data Exchange (ETDEWEB)

    Park, R.J.; Lee, S.J.; Sim, S.K. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1995-09-01

    Experimental and analytical studies of the crust formation and its effect on the molten pool coolability have been performed to examine the crust formation process as a function of boundary temperatures as well as to investigate heat transfer characteristics between molten pool and overlying water in order to evaluate coolability of the molten pool. The experimental test results have shown that the surface temperature of the bottom plate is a dominant parameter in the crust formation process of the molten pool. It is also found that the crust thickness of the case with direct coolant injection into the molten pool is greater than that of the case with a heat exchanger. Increasing mass flow rate of direct coolant injection to the molten pool does not affect the temperature of molten pool after the crust has been formed in the molten pool because the crust behaves as a thermal barrier. The Nusselt number between the molten pool and the coolant of the case with no crust formation is greater than that of the case with crust formation. The results of FLOW-3D analyses have shown that the temperature distribution contributes to the crust formation process due to Rayleigh-Benard natural convection flow.

  2. Biological Soil Crusts: Webs of Life in the Desert

    Science.gov (United States)

    Belnap, Jayne

    2001-01-01

    Although the soil surface may look like dirt to you, it is full of living organisms that are a vital part of desert ecosystems. This veneer of life is called a biological soil crust. These crusts are found throughout the world, from hot deserts to polar regions. Crusts generally cover all soil spaces not occupied by green plants. In many areas, they comprise over 70% of the living ground cover and are key in reducing erosion, increasing water retention, and increasing soil fertility. In most dry regions, these crusts are dominated by cyanobacteria (previously called blue-green algae), which are one of the oldest known life forms. Communities of soil crusts also include lichens, mosses, microfungi, bacteria, and green algae. These living organisms and their by-products create a continuous crust on the soil surface. The general color, surface appearance, and amount of coverage of these crusts vary depending on climate and disturbance patterns. Immature crusts are generally flat and the color of the soil, which makes them difficult to distinguish from bare ground. Mature crusts, in contrast, are usually bumpy and dark-colored due to the presence of lichens, mosses, and high densities of cyanobacteria and other organisms.

  3. 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...

  4. First results from the Mojave Volatiles Prospector (MVP) Field Campaign, a Lunar Polar Rover Mission Analog

    Science.gov (United States)

    Heldmann, J. L.; Colaprete, A.; Cook, A.; Deans, M. C.; Elphic, R. C.; Lim, D. S. S.; Skok, J. R.

    2014-12-01

    The Mojave Volatiles Prospector (MVP) project is a science-driven field program with the goal to produce critical knowledge for conducting robotic exploration of the Moon. MVP will feed science, payload, and operational lessons learned to the development of a real-time, short-duration lunar polar volatiles prospecting mission. MVP achieves these goals through a simulated lunar rover mission to investigate the composition and distribution of surface and subsurface volatiles in a natural and a priori unknown environment within the Mojave Desert, improving our understanding of how to find, characterize, and access volatiles on the Moon. The MVP field site is the Mojave Desert, selected for its low, naturally occurring water abundance. The Mojave typically has on the order of 2-6% water, making it a suitable lunar analog for this field test. MVP uses the Near Infrared and Visible Spectrometer Subsystem (NIRVSS), Neutron Spectrometer Subsystem (NSS), and a downward facing GroundCam camera on the KREX-2 rover to investigate the relationship between the distribution of volatiles and soil crust variation. Through this investigation, we mature robotic in situ instruments and concepts of instrument operations, improve ground software tools for real time science, and carry out publishable research on the water cycle and its connection to geomorphology and mineralogy in desert environments. A lunar polar rover mission is unlike prior space missions and requires a new concept of operations. The rover must navigate 3-5 km of terrain and examine multiple sites in in just ~6 days. Operational decisions must be made in real time, requiring constant situational awareness, data analysis and rapid turnaround decision support tools. This presentation will focus on the first science results and operational architecture findings from the MVP field deployment relevant to a lunar polar rover mission.

  5. 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

  6. SIRS Digues 2.0: A Cooperative Software For Levees Management

    Directory of Open Access Journals (Sweden)

    Moins Isabelle

    2016-01-01

    Full Text Available SIRS Digues is a computing tool that makes informations on levees more durable and accessible in order to enhance their management. The first version of the software, which was IRSTEA’s initiative, was deployed in 2004. The second version was released in 2015. This article aims at pointing out the innovative aspects of this last version. They concern thematic and functionalities, computing technics and architecture, and last but not least, the business model chosen in order to build a long lasting software. The software’s kernel is sketched to propose a general description of levees: it focuses on description of the levees and linked objects, on disorders that affects them, on works... Most of these topics were already broached by the first version. The kernel of the version 2 may be extended using optional thematic modules. These modules concern: vegetation monitoring, reporting (in coherence with current French regulatory requirements, riverbanks, riverbed... Main functionnalities perfomed by SIRS Digues V1 and V2 are : data structuring and centralisation, quick access to relevant data, reporting and mapping, etc. SIRS Digues 2.0 updates and improves already existing functionalities of the first version. SIRS Digues V2 relies on an documentoriented NoSQL database, CouchDB, and on geospatial libraries, Geotoolkit and Apache-SIS. SIRS Digues V2 was released with a copyleft license. Copyrights belong to the French levees managers’ society, “France Digues”, which acts as a cooperative. Members put their heads together in order to gather their financial capacities and fund software development. France Digues has got the technical and thematic expertise and supply various services to the members. This business model aims to ensure accessibility, durability and adaptability of the software.

  7. CHIC - Coupling Habitability, Interior and Crust

    Science.gov (United States)

    Noack, Lena; Labbe, Francois; Boiveau, Thomas; Rivoldini, Attilio; Van Hoolst, Tim

    2014-05-01

    We present a new code developed for simulating convection in terrestrial planets and icy moons. The code CHIC is written in Fortran and employs the finite volume method and finite difference method for solving energy, mass and momentum equations in either silicate or icy mantles. The code uses either Cartesian (2D and 3D box) or spherical coordinates (2D cylinder or annulus). It furthermore contains a 1D parametrised model to obtain temperature profiles in specific regions, for example in the iron core or in the silicate mantle (solving only the energy equation). The 2D/3D convection model uses the same input parameters as the 1D model, which allows for comparison of the different models and adaptation of the 1D model, if needed. The code has already been benchmarked for the following aspects: - viscosity-dependent rheology (Blankenbach et al., 1989) - pseudo-plastic deformation (Tosi et al., in preparation phase) - subduction mechanism and plastic deformation (Quinquis et al., in preparation phase) New features that are currently developed and benchmarked include: - compressibility (following King et al., 2009 and Leng and Zhong, 2008) - different melt modules (Plesa et al., in preparation phase) - freezing of an inner core (comparison with GAIA code, Huettig and Stemmer, 2008) - build-up of oceanic and continental crust (Noack et al., in preparation phase) The code represents a useful tool to couple the interior with the surface of a planet (e.g. via build-up and erosion of crust) and it's atmosphere (via outgassing on the one hand and subduction of hydrated crust and carbonates back into the mantle). It will be applied to investigate several factors that might influence the habitability of a terrestrial planet, and will also be used to simulate icy bodies with high-pressure ice phases. References: Blankenbach et al. (1989). A benchmark comparison for mantle convection codes. GJI 98, 23-38. Huettig and Stemmer (2008). Finite volume discretization for dynamic

  8. 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

  9. 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

  10. Energy for lunar resource exploitation

    Science.gov (United States)

    Glaser, Peter E.

    1992-02-01

    Humanity stands at the threshold of exploiting the known lunar resources that have opened up with the access to space. America's role in the future exploitation of space, and specifically of lunar resources, may well determine the level of achievement in technology development and global economic competition. Space activities during the coming decades will significantly influence the events on Earth. The 'shifting of history's tectonic plates' is a process that will be hastened by the increasingly insistent demands for higher living standards of the exponentially growing global population. Key to the achievement of a peaceful world in the 21st century, will be the development of a mix of energy resources at a societally acceptable and affordable cost within a realistic planning horizon. This must be the theme for the globally applicable energy sources that are compatible with the Earth's ecology. It is in this context that lunar resources development should be a primary goal for science missions to the Moon, and for establishing an expanding human presence. The economic viability and commercial business potential of mining, extracting, manufacturing, and transporting lunar resource based materials to Earth, Earth orbits, and to undertake macroengineering projects on the Moon remains to be demonstrated. These extensive activities will be supportive of the realization of the potential of space energy sources for use on Earth. These may include generating electricity for use on Earth based on beaming power from Earth orbits and from the Moon to the Earth, and for the production of helium 3 as a fuel for advanced fusion reactors.

  11. Production of Synthetic Lunar Simulants, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Zybek Advanced Products has proven the ability to produce industrial quantities of lunar simulant materials, including glass, agglutinate and melt breccias. These...

  12. Development of a lunar infrastructure

    Science.gov (United States)

    Burke, J. D.

    If humans are to reside continuously and productively on the Moon, they must be surrounded and supported there by an infrastructure having some attributes of the support systems that have made advanced civilization possible on Earth. Building this lunar infrastructure will, in a sense, be an investment. Creating it will require large resources from Earth, but once it exists it can do much to limit the further demands of a lunar base for Earthside support. What is needed for a viable lunar infrastructure? This question can be approached from two directions. The first is to examine history, which is essentially a record of growing information structures among humans on Earth (tribes, agriculture, specialization of work, education, ethics, arts and sciences, cities and states, technology). The second approach is much less secure but may provide useful insights: it is to examine the minimal needs of a small human community - not just for physical survival but for a stable existence with a net product output. This paper presents a summary, based on present knowledge of the Moon and of the likely functions of a human community there, of some of these infrastructure requirements, and also discusses possible ways to proceed toward meeting early infrastructure needs.

  13. Crusted Scabies in the Burned Patient

    DEFF Research Database (Denmark)

    Berg, Jais Oliver; Alsbjørn, Bjarne

    2011-01-01

    ; and 3) to design a treatment strategy for future patients. Case analysis and literature review were performed. The index patient had undiagnosed crusted scabies (sive Scabies norvegica) with the ensuing mite hyperinfestation when admitted to the department with minor acute dermal burns. Conservative...... healing and autograft healing were impaired because of the condition. Successful treatment of the burns was only accomplished secondarily to scabicide treatment. An outbreak of scabies among staff members indirectly led to diagnosis. CS is ubiquitous, and diagnosis may be difficult. This is the first...... report of a burned patient with CS in the English language literature. CS is also highly contagious and may lead to a nosocomial outbreak. Furthermore, CS seems to have a detrimental impact on the burned patient's course of treatment. A scabicide treatment is necessary to guarantee successful treatment...

  14. Crusting susceptibility in some allic Colombian soils

    International Nuclear Information System (INIS)

    Arias, Dora M; Madero E E; Amezquita E

    2001-01-01

    Many lab methods were used: dry and water soil aggregates stability, instability index and erosion index and their results were related with soil characteristics like texture, Fe and Al oxides and organic matter. Soil samples collected within 0-2.5 and 2.5-5 cm of the soil surface came from terrains with many kinds of both forest and savanna intervened systems. Those results were analyzed like a completely randomized designed. It was found that significative changes in oxides content could increase soil-crusting susceptibility unless soil humus was up to was up to 4%. In this sense, pastures or its rotation with rice and leguminous offer a best alternative for intervening these natural systems. Intensive land husbandry or monocultures with low stubble soil incorporation caused an increase in physical instability at the top of soil. Dry soil stability test and instability index were most adequate for these soils

  15. Moho vs crust-mantle boundary: Evolution of an idea

    Science.gov (United States)

    O'Reilly, Suzanne Y.; Griffin, W. L.

    2013-12-01

    The concept that the Mohorovicic Discontinuity (Moho) does not necessarily coincide with the base of the continental crust as defined by rock-type compositions was introduced in the early 1980s. This had an important impact on understanding the nature of the crust-mantle boundary using information from seismology and from deep-seated samples brought to the surface as xenoliths in magmas, or as tectonic terranes. The use of empirically-constrained P-T estimates to plot the locus of temperature vs depth for xenoliths defined a variety of geotherms depending on tectonic environment. The xenolith geotherms provided a framework for constructing lithological sections through the deep lithosphere, and revealed that the crust-mantle boundary in off-craton regions commonly is transitional over a depth range of about 5-20 km. Early seismic-reflection data showed common layering near the Moho, correlating with the petrological observation of multiple episodes of basaltic intrusion around the crust-mantle boundary. Developments in seismology, petrophysics and experimental petrology have refined interpretation of lithospheric domains. The expansion of in situ geochronology (especially zircon U-Pb ages and Hf-isotopes; Os isotopes of mantle sulfides) has defined tectonic events that affected whole crust-mantle sections, and revealed that the crust-mantle boundary can change in depth through time. However, the nature of the crust-mantle boundary in cratonic regions remains enigmatic, mainly due to lack of key xenoliths or exposed sections. The observation that the Moho may lie significantly deeper than the crust-mantle boundary has important implications for modeling the volume of the crust. Mapping the crust using seismic techniques alone, without consideration of the petrological problems, may lead to an overestimation of crustal thickness by 15-30%. This will propagate to large uncertainties in the calculation of elemental mass balances relevant to crust-formation processes

  16. SirT1 confers hypoxia-induced radioresistance via the modulation of c-Myc stabilization on hepatoma cells

    International Nuclear Information System (INIS)

    Xie Yuexia; Zhang Jianghong; Shao Chunlin; Xu Yanwu

    2012-01-01

    Intratumoral hypoxia is an important contributory factor to tumor cell resistance to radiotherapy. SirT1, a nicotinamide adenine dinucleotide (NAD + )-dependent histone/protein deacetylase, has been linked to the decrease of radiation-induced DNA damage and seems to be critical for cancer therapy. The purpose of this study was to investigate the role of SirT1 in hypoxia-induced radiation response on hepatoma cells. It was found that the administration with resveratrol, a putative SirT1 activator, enhanced the resistance of HepG2 cells against radiation-induced DNA damage of MN formation under hypoxia condition; while nicotinamide, a well-known SirT1 inhibitor, sensitized this radiation damage. Nevertheless, pretreatment of cells with 10058-F4, a specific inhibitor of c-Myc, almost eliminated the nicotinamide-induced radiosensitive effect. Further studies revealed that resveratrol inhibited c-Myc protein accumulation via up-regulation of SirT1 expression and deacetylase activity, and this loss of c-Myc protein was abolished by inhibiting its degradation in the presence of MG132, a potent inhibitor of proteasome. In contrast, nicotinamide attenuated c-Myc protein degradation induced by radiation under hypoxia through inhibition of SirT1 deacetylase activity. Our findings suggest that SirT1 could serve as a novel potent target of radiation-induced DNA damage and thus as a potential strategy to advance the efficiency of radiation therapy in hepatoma entities. (author)

  17. Spatial dynamic of mobile dunes, soil crusting and Yobe's bank ...

    African Journals Online (AJOL)

    In the fluvio-deltaic area of Kadzell, the soil crusting and the Yobe River retreat remain the major damages. The crusting area has been multiplied by more than two while the lateral migration of the Yobe bank reached near of 3 m.yr-1. This study highlights the key role of man in the process of degradation related to climate ...

  18. Soil Characteristics of Crusted outside and Subcanopy Areas of four ...

    African Journals Online (AJOL)

    The results on compaction, salinity, pH, water holding capacity, respiration and organic carbon supported the model. The crust:shrub ratio is crucial for the functioning and sustained productivity of the system. Keywords: Soil characteristics; shrub subcanopy; crust; sink-source, Negev desert [IJARD Vol.3 2002: 162-170] ...

  19. Growth of the continental crust: constraints from radiogenic isotope geochemistry

    International Nuclear Information System (INIS)

    Taylor, P.N.

    1988-01-01

    Most models for evolution of continental crust are expressed in the form of a diagram illustrating the cumulative crustal mass (normalized relative to the present crustal mass) as a function of time. Thus, geochronological data inevitably play a major role in either constructing or testing crustal growth models. For all models, determining the start-time for effective crustal accretion is of vital importance. To this end, the continuing search for, and reliable characterization of, the most ancient crustal rock-units remains a worthy enterprise. Another important role for geochronology and radiogenic isotope geochemistry is to assess the status of major geological events as period either of new crust generation or of reworking of earlier formed continental crust. For age characterization of major geological provinces, using the critieria outined, the mass (or volume) of crust surviving to the present day should be determinable as a function of crust formation age. More recent developments, however, appear to set severe limitations on recycling of crust, at least by the process of sediment subduction. In modeling crustal growth without recycling, valuable constaints on growth rate variations through time can be provided if variations in the average age of the continental crust can be monitored through geological history. The question of the average age of the exposed continental crust was addressed by determining Sm-Nd crustal residence model ages (T-CR) for fine-grained sediment loads of many of the world's major rivers

  20. Increasing cotton stand establishment in soils prone to soil crusting

    Science.gov (United States)

    Many factors can contribute to poor cotton stand establishment, and cotton is notorious for its weak seedling vigor. Soil crusting can be a major factor hindering cotton seedling emergence in many of the cotton production regions of the US and the world. Crusting is mainly an issue in silty soils ...

  1. Magnetic field effects on the crust structure of neutron stars

    Science.gov (United States)

    Franzon, B.; Negreiros, R.; Schramm, S.

    2017-12-01

    We study the effects of high magnetic fields on the structure and on the geometry of the crust in neutron stars. We find that the crust geometry is substantially modified by the magnetic field inside the star. We build stationary and axis-symmetric magnetized stellar models by using well-known equations of state to describe the neutron star crust, namely, the Skyrme model for the inner crust and the Baym-Pethick-Sutherland equation of state for the outer crust. We show that the magnetic field has a dual role, contributing to the crust deformation via the electromagnetic interaction (manifested in this case as the Lorentz force) and by contributing to curvature due to the energy stored in it. We also study a direct consequence of the crust deformation due to the magnetic field: the thermal relaxation time. This quantity, which is of great importance to the thermal evolution of neutron stars, is sensitive to the crust properties, and, as such, we show that it may be strongly affected by the magnetic field.

  2. Fkh1 and Fkh2 associate with Sir2 to control CLB2 transcription under normal and oxidative stress conditions

    Directory of Open Access Journals (Sweden)

    Christian eLinke

    2013-07-01

    Full Text Available The Forkhead box family of transcription factors is evolutionary conserved from yeast to higher eukaryotes and its members are involved in many physiological processes including metabolism, DNA repair, cell cycle, stress resistance, apoptosis and aging. In budding yeast, four Forkhead transcription factors were identified, namely Fkh1, Fkh2, Fhl1, and Hcm1, which are implicated in chromatin silencing, cell cycle regulation and stress response. These factors impinge transcriptional regulation during cell cycle progression, and histone deacetylases play an essential role in this process, e.g. the nuclear localisation of Hcm1 depends on Sir2 activity, whereas Sin3/Rpd3 silence cell cycle specific gene transcription in G2/M phase. However, a direct involvement of Sir2 in Fkh1/Fkh2-dependent regulation of target genes is at present unknown. Here, we show that Fkh1 and Fkh2 associate with Sir2 in G1 and M phase, and that Fkh1/Fkh2-mediated activation of reporter genes is antagonized by Sir2. We further report that Sir2 overexpression strongly affects cell growth in an Fkh1/Fkh2-dependent manner. In addition, Sir2 regulates the expression of the mitotic cyclin Clb2 through Fkh1/Fkh2-mediated binding to the CLB2 promoter in G1 and M phase. We finally demonstrate that Sir2 is also enriched at the CLB2 promoter under stress conditions, and that the nuclear localization of Sir2 is dependent on Fkh1 and Fkh2. Taken together, our results show a functional interplay between Fkh1/Fkh2 and Sir2 suggesting a novel mechanism of cell cycle repression. Thus, in budding yeast, not only the regulation of G2/M gene expression but also the protective response against stress could be directly coordinated by Fkh1 and Fkh2.

  3. Echo simulation of lunar penetrating radar: based on a model of inhomogeneous multilayer lunar regolith structure

    International Nuclear Information System (INIS)

    Dai Shun; Su Yan; Xiao Yuan; Feng Jian-Qing; Xing Shu-Guo; Ding Chun-Yu

    2014-01-01

    Lunar Penetrating Radar (LPR) based on the time domain Ultra-Wideband (UWB) technique onboard China's Chang'e-3 (CE-3) rover, has the goal of investigating the lunar subsurface structure and detecting the depth of lunar regolith. An inhomogeneous multi-layer microwave transfer inverse-model is established. The dielectric constant of the lunar regolith, the velocity of propagation, the reflection, refraction and transmission at interfaces, and the resolution are discussed. The model is further used to numerically simulate and analyze temporal variations in the echo obtained from the LPR attached on CE-3's rover, to reveal the location and structure of lunar regolith. The thickness of the lunar regolith is calculated by a comparison between the simulated radar B-scan images based on the model and the detected result taken from the CE-3 lunar mission. The potential scientific return from LPR echoes taken from the landing region is also discussed

  4. Echo simulation of lunar penetrating radar: based on a model of inhomogeneous multilayer lunar regolith structure

    Science.gov (United States)

    Dai, Shun; Su, Yan; Xiao, Yuan; Feng, Jian-Qing; Xing, Shu-Guo; Ding, Chun-Yu

    2014-12-01

    Lunar Penetrating Radar (LPR) based on the time domain Ultra-Wideband (UWB) technique onboard China's Chang'e-3 (CE-3) rover, has the goal of investigating the lunar subsurface structure and detecting the depth of lunar regolith. An inhomogeneous multi-layer microwave transfer inverse-model is established. The dielectric constant of the lunar regolith, the velocity of propagation, the reflection, refraction and transmission at interfaces, and the resolution are discussed. The model is further used to numerically simulate and analyze temporal variations in the echo obtained from the LPR attached on CE-3's rover, to reveal the location and structure of lunar regolith. The thickness of the lunar regolith is calculated by a comparison between the simulated radar B-scan images based on the model and the detected result taken from the CE-3 lunar mission. The potential scientific return from LPR echoes taken from the landing region is also discussed.

  5. 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.

  6. NASA Lunar and Meteorite Sample Disk Program

    Science.gov (United States)

    Foxworth, Suzanne

    2017-01-01

    The Lunar and Meteorite Sample Disk Program is designed for K-12 classroom educators who work in K-12 schools, museums, libraries, or planetariums. Educators have to be certified to borrow the Lunar and Meteorite Sample Disks by attending a NASA Certification Workshop provided by a NASA Authorized Sample Disk Certifier.

  7. Low temperature thermophysical properties of lunar soil

    Science.gov (United States)

    Cremers, C. J.

    1973-01-01

    The thermal conductivity and thermal diffusivity of lunar fines samples from the Apollo 11 and Apollo 12 missions, determined at low temperatures as a function of temperature and various densities, are reviewed. It is shown that the thermal conductivity of lunar soil is nearly the same as that of terrestrial basaltic rock under the same temperature and pressure conditions.

  8. Lunar landing and launch facilities and operations

    Science.gov (United States)

    1988-01-01

    A preliminary design of a lunar landing and launch facility for a Phase 3 lunar base is formulated. A single multipurpose vehicle for the lunar module is assumed. Three traffic levels are envisioned: 6, 12, and 24 landings/launches per year. The facility is broken down into nine major design items. A conceptual description of each of these items is included. Preliminary sizes, capacities, and/or other relevant design data for some of these items are obtained. A quonset hut tent-like structure constructed of aluminum rods and aluminized mylar panels is proposed. This structure is used to provide a constant thermal environment for the lunar modules. A structural design and thermal analysis is presented. Two independent designs for a bridge crane to unload/load heavy cargo from the lunar module are included. Preliminary investigations into cryogenic propellant storage and handling, landing/launch guidance and control, and lunar module maintenance requirements are performed. Also, an initial study into advanced concepts for application to Phase 4 or 5 lunar bases has been completed in a report on capturing, condensing, and recycling the exhaust plume from a lunar launch.

  9. Krypton and xenon in lunar fines

    Science.gov (United States)

    Basford, J. R.; Dragon, J. C.; Pepin, R. O.; Coscio, M. R., Jr.; Murthy, V. R.

    1973-01-01

    Data from grain-size separates, stepwise-heated fractions, and bulk analyses of 20 samples of fines and breccias from five lunar sites are used to define three-isotope and ordinate intercept correlations in an attempt to resolve the lunar heavy rare gas system in a statistically valid approach. Tables of concentrations and isotope compositions are given.

  10. Lunar ranging instrument for Chandrayaan-1

    Indian Academy of Sciences (India)

    ... Committee on Scientific Values · Project Lifescape · Scientific Data of Public Interest ... Lunar Laser Ranging Instrument (LLRI)proposed for the first Indian lunar ... field by precisely measuring the altitude from a polar orbit around the Moon. ... Laboratory for Electro-Optics Systems, Indian Space Research Organization ...

  11. Armstrong practices in Lunar Module simulator

    Science.gov (United States)

    1969-01-01

    Neil A. Armstrong, Commander for the Apollo 11 Moon-landing mission, practices for the historic event in a Lunar Module simulator in the Flight Crew Training building at KSC. Accompanying Armstrong on the Moon flight will be Command Module Pilot Michael Collins and Lunar Module Pilot Edwin E. Aldrin Jr.

  12. The origin of lunar mascons - Analysis of the Bouguer gravity associated with Grimaldi

    Science.gov (United States)

    Phillips, R. J.; Dvorak, J.

    1981-01-01

    Grimaldi is a relatively small multi-ringed basin located on the western limb of the moon. Spacecraft free-air gravity data reveal a mascon associated with the inner ring of this structure, and the topographic correction to the local lunar gravity field indicates a maximum Bouguer anomaly of +90 milligals at an altitude of 70 kilometers. Approximately 20% of this positive Bouguer anomaly can be attributed to the mare material lying within the inner ring of this basin. From a consideration of the Bouguer gravity and structure of large lunar craters comparable in size to the central basin of Grimaldi, it is suggested that the remaining positive Bouguer anomaly is due to a centrally uplifted plug of lunar mantle material. The uplift was caused by inward crustal collapse which also resulted in the formation of the concentric outer scarp of Grimaldi. In addition, an annulus of low density material, probably a combination of ejecta and in situ breccia, is required to fully reproduce the Bouguer gravity signature across this basin. It is proposed that Grimaldi supplies a critical test in the theory of mascon formation: crustal collapse by ring faulting and central uplift to depths of the crust-mantle boundary are requisites

  13. Timing of Crystallisation of the Lunar Magma Ocean Constrained by the Oldest Zircon

    Science.gov (United States)

    Nemchin, A.; Timms, N.; Pidgeon, R.; Geisler, T.; Reddy, S.; Meyer, C.

    2009-01-01

    The presently favoured concept for the early evolution of the Moon involves consolidation of debris from a giant impact of a Mars sized body with Earth forming a primitive Moon with a thick global layer of melt referred to as the Lunar Magma Ocean1 . It is widely accepted that many significant features observed on the Moon today are the result of crystallisation of this magma ocean. However, controversy exists over the precise timing and duration of the crystallisation process. Resolution of this problem depends on the establishment of precise and robust key crystallisation time points. We report a 4417 6 Myr old zircon in lunar breccia sample 72215,195, which provides a precisely determined younger limit for the solidification of the Lunar Magma Ocean. A model based on these data, together with the age of the Moon forming giant impact, defines an exponential time frame for crystallisation and suggests formation of anorthositic crust after about 80-85% of the magma ocean was solidified. In combination with other zircon ages the 4417 +/- 6 Myr age also suggests that the very small (less than a few per cent) residual portion of the magma ocean continued to solidify during the following 300-500 m.y.

  14. 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

  15. 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

  16. 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

  17. 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.

  18. Lunar soil as shielding against space radiation

    Energy Technology Data Exchange (ETDEWEB)

    Miller, J. [Lawrence Berkeley National Laboratory, MS 83R0101, 1 Cyclotron Road, Berkeley, CA 94720 (United States)], E-mail: miller@lbl.gov; Taylor, L. [Planetary Geosciences Institute, Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN 37996 (United States); Zeitlin, C. [Southwest Research Institute, Boulder, CO 80302 (United States); Heilbronn, L. [Department of Nuclear Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Guetersloh, S. [Department of Nuclear Engineering, Texas A and M University, College Station, TX 77843 (United States); DiGiuseppe, M. [Northrop Grumman Corporation, Bethpage, NY 11714 (United States); Iwata, Y.; Murakami, T. [National Institute of Radiological Sciences, Chiba 263-8555 (Japan)

    2009-02-15

    We have measured the radiation transport and dose reduction properties of lunar soil with respect to selected heavy ion beams with charges and energies comparable to some components of the galactic cosmic radiation (GCR), using soil samples returned by the Apollo missions and several types of synthetic soil glasses and lunar soil simulants. The suitability for shielding studies of synthetic soil and soil simulants as surrogates for lunar soil was established, and the energy deposition as a function of depth for a particular heavy ion beam passing through a new type of lunar highland simulant was measured. A fragmentation and energy loss model was used to extend the results over a range of heavy ion charges and energies, including protons at solar particle event (SPE) energies. The measurements and model calculations indicate that a modest amount of lunar soil affords substantial protection against primary GCR nuclei and SPE, with only modest residual dose from surviving charged fragments of the heavy beams.

  19. Le continent noir du désir masculin : Colet et Flaubert, encore

    OpenAIRE

    Vinken, Barbara

    2010-01-01

    Il y a peu d’échanges de lettres qui surprennent le lecteur aussi douloureusement que celui entre Louise Colet et Gustave Flaubert. Rarement, l’espoir qui sommeille au fond de tout lecteur d’une histoire d’amour heureux fut à ce point frustré.Les études de Freud – un des plus grands sceptiques en matière d’amour – sur la vie sexuelle éclairent les vicissitudes du désir amoureux masculin. Les Lettres de Flaubert à Colet sont la mise en scène dramatique d’un désir qui suit les complications du ...

  20. Determination of the Geographical Origin of All Commercial Hake Species by Stable Isotope Ratio (SIR) Analysis.

    Science.gov (United States)

    Carrera, Mónica; Gallardo, José M

    2017-02-08

    The determination of the geographical origin of food products is relevant to comply with the legal regulations of traceability, to avoid food fraud, and to guarantee food quality and safety to the consumers. For these reasons, stable isotope ratio (SIR) analysis using an isotope ratio mass spectrometry (IRMS) instrument is one of the most useful techniques for evaluating food traceability and authenticity. The present study was aimed to determine, for the first time, the geographical origin for all commercial fish species belonging to the Merlucciidae family using SIR analysis of carbon (δ 13 C) and nitrogen (δ 15 N). The specific results enabled their clear classification according to the FAO (Food and Agriculture Organization of the United Nations) fishing areas, latitude, and geographical origin in the following six different clusters: European, North African, South African, North American, South American, and Australian hake species.

  1. Mutations that Allow SIR2 Orthologs to Function in a NAD+-Depleted Environment.

    Science.gov (United States)

    Ondracek, Caitlin R; Frappier, Vincent; Ringel, Alison E; Wolberger, Cynthia; Guarente, Leonard

    2017-03-07

    Sirtuin enzymes depend on NAD + to catalyze protein deacetylation. Therefore, the lowering of NAD + during aging leads to decreased sirtuin activity and may speed up aging processes in laboratory animals and humans. In this study, we used a genetic screen to identify two mutations in the catalytic domain of yeast Sir2 that allow the enzyme to function in an NAD + -depleted environment. These mutant enzymes give rise to a significant increase of yeast replicative lifespan and increase deacetylation by the Sir2 ortholog, SIRT1, in mammalian cells. Our data suggest that these mutations increase the stability of the conserved catalytic sirtuin domain, thereby increasing the catalytic efficiency of the mutant enzymes. Our approach to identifying sirtuin mutants that permit function in NAD + -limited environments may inform the design of small molecules that can maintain sirtuin activity in aging organisms. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Sir Peter Medawar: science, creativity and the popularization of Karl Popper

    Science.gov (United States)

    Calver, Neil

    2013-01-01

    Sir Peter Medawar was respected by scientists and literati alike. It was perhaps not surprising, then, that he would choose to involve himself in the ‘two cultures’ debate of 1959 and beyond. The focus of his intervention was the philosophy of Sir Karl Popper. However, Medawar's Popper was not the guru of falsification familiar from philosophy textbooks. Medawar's distinctive interpretation of Popper treated him instead as the source of insights into the role of creativity and imagination in scientific inquiry. This paper traces the context for Medawar's adoption of Popperian philosophy, together with its application before the debate. It then examines, within the context of the debate itself, the way in which Medawar attempted to reconcile scientific inquiry with literary practice. Medawar became increasingly convinced that not only was induction epistemologically unsound, but it was also damaging to the public role of the scientist. His construction of Popperianism would, he envisaged, provide a worthy alternative for scientists’ self-image.

  3. The threshold of a stochastic delayed SIR epidemic model with temporary immunity

    Science.gov (United States)

    Liu, Qun; Chen, Qingmei; Jiang, Daqing

    2016-05-01

    This paper is concerned with the asymptotic properties of a stochastic delayed SIR epidemic model with temporary immunity. Sufficient conditions for extinction and persistence in the mean of the epidemic are established. The threshold between persistence in the mean and extinction of the epidemic is obtained. Compared with the corresponding deterministic model, the threshold affected by the white noise is smaller than the basic reproduction number R0 of the deterministic system.

  4. Traveling waves in a delayed SIR model with nonlocal dispersal and nonlinear incidence

    Science.gov (United States)

    Zhang, Shou-Peng; Yang, Yun-Rui; Zhou, Yong-Hui

    2018-01-01

    This paper is concerned with traveling waves of a delayed SIR model with nonlocal dispersal and a general nonlinear incidence. The existence and nonexistence of traveling waves of the system are established respectively by Schauder's fixed point theorem and two-sided Laplace transform. It is also shown that the spread speed c is influenced by the dispersal rate of the infected individuals and the delay τ.

  5. Global analysis of multi-strains SIS, SIR and MSIR epidemic models

    OpenAIRE

    Bichara , Derdei; Iggidr , Abderrahman; Sallet , Gauthier

    2014-01-01

    International audience; We consider SIS, SIR and MSIR models with standard mass action and varying population, with $n$ different pathogen strains of an infectious disease. We also consider the same models with vertical transmission. We prove that under generic conditions a competitive exclusion principle holds. To each strain a basic reproduction ratio can be associated. It corresponds to the case where only this strain exists. The basic reproduction ratio of the complete system is the maxim...

  6. Competitive exclusion principle for SIS and SIR models with n strains

    OpenAIRE

    Bichara , Derdei; Iggidr , Abderrahman; Sallet , Gauthier

    2012-01-01

    We consider SIS and SIR models with standard mass action and varying population, with $n$ different pathogen strains of an infectious disease. We also consider the same models with vertical transmission. We prove that under generic conditions a competitive exclusion principle holds. To each strain a basic reproduction ratio can be associated. It corresponds to the case where only this strain exists. The basic reproduction ratio of the complete system is the maximum of each individual basic re...

  7. Design of power controller in CDMA system with power and SIR error minimization

    Institute of Scientific and Technical Information of China (English)

    Shulan KONG; Huanshui ZHANG; Zhaosheng ZHANG; Hongxia WANG

    2007-01-01

    In this paper, an uplink power control problem is considered for code division multiple access (CDMA) systems. A distributed algorithm is proposed based on linear quadratic optimal control theory. The proposed scheme minimizes the sum of the power and the error of signal-to-interference ratio (SIR). A power controller is designed by constructing an optimization problem of a stochastic linear quadratic type in Krein space and solving a Kalman filter problem.

  8. Analysis of Active Lava Flows on Kilauea Volcano, Hawaii, Using SIR-C Radar Correlation Measurements

    Science.gov (United States)

    Zebker, H. A.; Rosen, P.; Hensley, S.; Mouginis-Mark, P. J.

    1995-01-01

    Precise eruption rates of active pahoehoe lava flows on Kilauea volcano, Hawaii, have been determined using spaceborne radar data acquired by the Space Shuttle Imaging Radar-C (SIR-C). Measurement of the rate of lava flow advance, and the determination of the volume of new material erupted in a given period of time, are among the most important observations that can be made when studying a volcano.

  9. Dynamic Behavior for an SIRS Model with Nonlinear Incidence Rate and Treatment

    Directory of Open Access Journals (Sweden)

    Junhong Li

    2013-01-01

    Full Text Available This paper considers an SIRS model with nonlinear incidence rate and treatment. It is assumed that susceptible and infectious individuals have constant immigration rates. We investigate the existence of equilibrium and prove the global asymptotical stable results of the endemic equilibrium. We then obtained that the model undergoes a Hopf bifurcation and existences a limit cycle. Some numerical simulations are given to illustrate the analytical results.

  10. Thermal vacuum test of space equipment: tests of SIR-2 instrument Chandrayaan-1 mission

    Science.gov (United States)

    Sitek, P.

    2008-11-01

    We describe the reasons of proceeding Thermal-Vacuum tests for space electronic. We will answer on following questions: why teams are doing TV tests, what kind of phases should be simulated, which situations are the most critical during TV tests, what kind of results should be expected, which errors can be detect. As an example, will be shown TV-test of SIR-2 instrument for Chandrayaan-1 moon mission.

  11. Milestones in plant sulfur research on sulfur-induced-resistance (SIR in Europe

    Directory of Open Access Journals (Sweden)

    Elke eBloem

    2015-01-01

    Full Text Available Until the 1970´s of the last century sulfur (S was mainly regarded as a pollutant being the main contributor of acid rain, causing forest dieback in central Europe. When Clean Air Acts came into force at the start of the 1980´s SO2 contaminations in the air were consequently reduced within the next years. S changed from an unwanted pollutant into a lacking plant nutrient in agriculture since agricultural fields were no longer fertilized indirectly by industrial pollution. S deficiency was first noticed in Brassica crops that display an especially high S demand because of its content of S-containing secondary metabolites, the glucosinolates. In Scotland, where S depositions decreased even faster than in continental Europe, an increasing disease incidence with Pyrenopeziza brassicae was observed in oilseed rape in the beginning 1990´s and the concept of sulfur-induced-resistance (SIR was developed after a relationship between the S status and the disease incidence was uncovered. Since then a lot of research was carried out to unravel the background of SIR in the metabolism of agricultural crops and to identify metabolites, enzymes and reactions, which are potentially activated by the S metabolism to combat fungal pathogens. The S status of the crop is affecting many different plant features such as color and scent of flowers, pigments in leaves, metabolite concentrations and the release of gaseous S compounds which are directly influencing the desirability of a crop for a variety of different organisms from microorganisms, over insects and slugs to the point of grazing animals.The present paper is an attempt to sum up the knowledge about the effect of the S nutritional status of agricultural crops on parameters that are directly related to their health status and by this to SIR. Milestones in SIR research are compiled, open questions are addressed and future projections were developed.

  12. Montaigne, Sir Ralph Bankes and other English readers of the Essais.

    OpenAIRE

    O'Brien, John

    2013-01-01

    This article deals with a hitherto unknown and unpublished early modern English manuscript account of Montaigne's Essais by Sir Ralph Bankes (1631?–77) of Kingston Lacy in Dorset. Bankes's account covers a range of features in Montaigne's work: crucial elements of self-portraiture such as judgement, but also his attitude to women and doctors. These characteristics are analysed and compared first with Montaigne's own pronouncements about the aspects Bankes selects and secondly with two other s...

  13. A thin, dense crust for Mercury

    Science.gov (United States)

    Sori, Michael M.

    2018-05-01

    Crustal thickness is a crucial geophysical parameter in understanding the geology and geochemistry of terrestrial planets. Recent development of mathematical techniques suggests that previous studies based on assumptions of isostasy overestimated crustal thickness on some of the solid bodies of the solar system, leading to a need to revisit those analyses. Here, I apply these techniques to Mercury. Using MESSENGER-derived elemental abundances, I calculate a map of grain density (average 2974 ± 89 kg/m3) which shows that Pratt isostasy is unlikely to be a major compensation mechanism of Mercury's topography. Assuming Airy isostasy, I find the best fit value for Mercury's mean crustal thickness is 26 ± 11 km, 25% lower than the most recently reported and previously thinnest number. Several geological implications follow from this relatively low value for crustal thickness, including showing that the largest impacts very likely excavated mantle material onto Mercury's surface. The new results also show that Mercury and the Moon have a similar proportion of their rocky silicates composing their crusts, and thus Mercury is not uniquely efficient at crustal production amongst terrestrial bodies. Higher resolution topography and gravity data, especially for the southern hemisphere, will be necessary to refine Mercury's crustal parameters further.

  14. Disease mapping based on stochastic SIR-SI model for Dengue and Chikungunya in Malaysia

    Energy Technology Data Exchange (ETDEWEB)

    Samat, N. A.; Ma' arof, S. H. Mohd Imam [Department of Mathematics, Faculty of Science and Mathematics, Universiti Pendidikan Sultan Idris, 35900 Tanjung Malim, Perak (Malaysia)

    2014-12-04

    This paper describes and demonstrates a method for relative risk estimation which is based on the stochastic SIR-SI vector-borne infectious disease transmission model specifically for Dengue and Chikungunya diseases in Malaysia. Firstly, the common compartmental model for vector-borne infectious disease transmission called the SIR-SI model (susceptible-infective-recovered for human populations; susceptible-infective for vector populations) is presented. This is followed by the explanations on the stochastic SIR-SI model which involve the Bayesian description. This stochastic model then is used in the relative risk formulation in order to obtain the posterior relative risk estimation. Then, this relative estimation model is demonstrated using Dengue and Chikungunya data of Malaysia. The viruses of these diseases are transmitted by the same type of female vector mosquito named Aedes Aegypti and Aedes Albopictus. Finally, the findings of the analysis of relative risk estimation for both Dengue and Chikungunya diseases are presented, compared and displayed in graphs and maps. The distribution from risk maps show the high and low risk area of Dengue and Chikungunya diseases occurrence. This map can be used as a tool for the prevention and control strategies for both diseases.

  15. Disease mapping based on stochastic SIR-SI model for Dengue and Chikungunya in Malaysia

    International Nuclear Information System (INIS)

    Samat, N. A.; Ma'arof, S. H. Mohd Imam

    2014-01-01

    This paper describes and demonstrates a method for relative risk estimation which is based on the stochastic SIR-SI vector-borne infectious disease transmission model specifically for Dengue and Chikungunya diseases in Malaysia. Firstly, the common compartmental model for vector-borne infectious disease transmission called the SIR-SI model (susceptible-infective-recovered for human populations; susceptible-infective for vector populations) is presented. This is followed by the explanations on the stochastic SIR-SI model which involve the Bayesian description. This stochastic model then is used in the relative risk formulation in order to obtain the posterior relative risk estimation. Then, this relative estimation model is demonstrated using Dengue and Chikungunya data of Malaysia. The viruses of these diseases are transmitted by the same type of female vector mosquito named Aedes Aegypti and Aedes Albopictus. Finally, the findings of the analysis of relative risk estimation for both Dengue and Chikungunya diseases are presented, compared and displayed in graphs and maps. The distribution from risk maps show the high and low risk area of Dengue and Chikungunya diseases occurrence. This map can be used as a tool for the prevention and control strategies for both diseases

  16. Simulation of emotional contagion using modified SIR model: A cellular automaton approach

    Science.gov (United States)

    Fu, Libi; Song, Weiguo; Lv, Wei; Lo, Siuming

    2014-07-01

    Emotion plays an important role in the decision-making of individuals in some emergency situations. The contagion of emotion may induce either normal or abnormal consolidated crowd behavior. This paper aims to simulate the dynamics of emotional contagion among crowds by modifying the epidemiological SIR model to a cellular automaton approach. This new cellular automaton model, entitled the “CA-SIRS model”, captures the dynamic process ‘susceptible-infected-recovered-susceptible', which is based on SIRS contagion in epidemiological theory. Moreover, in this new model, the process is integrated with individual movement. The simulation results of this model show that multiple waves and dynamical stability around a mean value will appear during emotion spreading. It was found that the proportion of initial infected individuals had little influence on the final stable proportion of infected population in a given system, and that infection frequency increased with an increase in the average crowd density. Our results further suggest that individual movement accelerates the spread speed of emotion and increases the stable proportion of infected population. Furthermore, decreasing the duration of an infection and the probability of reinfection can markedly reduce the number of infected individuals. It is hoped that this study will be helpful in crowd management and evacuation organization.

  17. Nicotinamide supplementation phenocopies SIR2 inactivation by modulating carbon metabolism and respiration during yeast chronological aging.

    Science.gov (United States)

    Orlandi, Ivan; Pellegrino Coppola, Damiano; Strippoli, Maurizio; Ronzulli, Rossella; Vai, Marina

    2017-01-01

    Nicotinamide (NAM), a form of vitamin B 3 , is a byproduct and noncompetitive inhibitor of the deacetylation reaction catalyzed by Sirtuins. These represent a family of evolutionarily conserved NAD + -dependent deacetylases that are well-known critical regulators of metabolism and aging and whose founding member is Sir2 of Saccharomyces cerevisiae. Here, we investigated the effects of NAM supplementation in the context of yeast chronological aging, the established model for studying aging of postmitotic quiescent mammalian cells. Our data show that NAM supplementation at the diauxic shift results in a phenocopy of chronologically aging sir2Δ cells. In fact, NAM-supplemented cells display the same chronological lifespan extension both in expired medium and extreme Calorie Restriction. Furthermore, NAM allows the cells to push their metabolism toward the same outcomes of sir2Δ cells by elevating the level of the acetylated Pck1. Both these cells have the same metabolic changes that concern not only anabolic pathways such as an increased gluconeogenesis but also respiratory activity in terms both of respiratory rate and state of respiration. In particular, they have a higher respiratory reserve capacity and a lower non-phosphorylating respiration that in concert with a low burden of superoxide anions can affect positively chronological aging. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  18. Disease mapping based on stochastic SIR-SI model for Dengue and Chikungunya in Malaysia

    Science.gov (United States)

    Samat, N. A.; Ma'arof, S. H. Mohd Imam

    2014-12-01

    This paper describes and demonstrates a method for relative risk estimation which is based on the stochastic SIR-SI vector-borne infectious disease transmission model specifically for Dengue and Chikungunya diseases in Malaysia. Firstly, the common compartmental model for vector-borne infectious disease transmission called the SIR-SI model (susceptible-infective-recovered for human populations; susceptible-infective for vector populations) is presented. This is followed by the explanations on the stochastic SIR-SI model which involve the Bayesian description. This stochastic model then is used in the relative risk formulation in order to obtain the posterior relative risk estimation. Then, this relative estimation model is demonstrated using Dengue and Chikungunya data of Malaysia. The viruses of these diseases are transmitted by the same type of female vector mosquito named Aedes Aegypti and Aedes Albopictus. Finally, the findings of the analysis of relative risk estimation for both Dengue and Chikungunya diseases are presented, compared and displayed in graphs and maps. The distribution from risk maps show the high and low risk area of Dengue and Chikungunya diseases occurrence. This map can be used as a tool for the prevention and control strategies for both diseases.

  19. Analysis of data acquired by Shuttle Imaging Radar SIR-A and Landsat Thematic Mapper over Baldwin County, Alabama

    Science.gov (United States)

    Wu, S.-T.

    1985-01-01

    Seasonally compatible data collected by SIR-A and by Landsat 4 TM over the lower coastal plain in Alabama were coregistered, forming a SIR-A/TM multichannel data set with 30 m x 30 m pixel size. Spectral signature plots and histogram analysis of the data were used to observe data characteristics. Radar returns from pine forest classes correlated highly with the tree ages, suggesting the potential utility of microwave remote sensing for forest biomass estimation. As compared with the TM-only data set, the use of SIR-A/TM data set improved classification accuracy of the seven land cover types studied. In addition, the SIR-A/TM classified data support previous finding by Engheta and Elachi (1982) that microwave data appear to be correlated with differing bottomland hardwood forest vegetation as associated with varying water regimens (i.e., wet versus dry).

  20. 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.

  1. Hoarding symptoms among psychiatric outpatients: confirmatory factor analysis and psychometric properties of the Saving Inventory – Revised (SI-R

    Directory of Open Access Journals (Sweden)

    Siau Pheng Lee

    2016-10-01

    Full Text Available Abstract Background The growing interest in problematic hoarding as an independent clinical condition has led to the development of the Saving Inventory-Revised (SI-R to assess hoarding phenomenology. The SI-R is one of the most widely used instruments to measure hoarding symptoms; however, it lacks validation in non-Western samples. Methods The current study examined the construct, convergent, and discriminant validity of the SI-R among 500 outpatients at a psychiatric hospital in Singapore. The three-factor structure solution of the SI-R was fitted in a confirmatory factor analysis. Results The final model achieved mediocre fit (χ2 = 1026.02, df = 186; RMSEA = 0.095, SRMR = 0.06; CFI = 0.86; NNFI = 0.85. Two reverse-coded items (items 2 and 4 were removed due to insufficient factor loadings, resulting in the modified 21-item SI-R (SIR-21. Our findings indicate the need to further examine the construct validity of the SI-R, particularly in non-Western samples. Nonetheless, correlations with other hoarding-related constructs, such as anxiety (Beck Anxiety Inventory and depression (Beck Depression Inventory-II, supported the convergent and discriminant validity of the SIR-21 in our sample. Conclusions Findings in our current majority Chinese sample were consistent with previous observations from other Chinese samples. Implications were discussed from a cross-cultural perspective, such as cultural emphasis on saving for future use and overlap between the concepts of discarding and acquiring in Chinese samples. Future studies should also examine differences among other ethnic groups (e.g., Malay, Indian.

  2. The Complex Stratigraphy of the Highland Crust in the Serenitatis Region of the Moon Inferred from Mineral Fragment Chemistry

    Science.gov (United States)

    Ryder, Graham; Norman, Marc D.; Taylor, G. Jeffrey

    1997-01-01

    Large impact basins are natural drill holes into the Moon, and their ejecta carries unique information about the rock types and stratigraphy of the lunar crust. We have conducted an electron microprobe study of mineral fragments in the poikilitic melt breccias collected from the Taurus Mountains at the Apollo 17 landing site. These breccias are virtually unanimously agreed to be impact melt produced in the Serenitatis impact event. They contain lithic fragments and much more abundant mineral fragments of crustal origin. We have made precise microprobe analyses of minor element abundances in fragments of olivine, pyroxene, and plagioclase to provide new information on the possible source rocks and the crustal stratigraphy in the Serenitatis region. These data were also intended to elucidate the nature of the cryptic geochemical component in breccias such as these with low-K Fra Mauro basalt compositions. We chose the finest-grained (i.e., most rapidly quenched) breccias for study, to avoid reacted and partly assimilated fragments as much as possible. Most of the mineral fragments appear to have been derived from rocks that would fall into the pristine igneous Mg-suite as represented by lithic fragments in the Apollo collection, or reasonable extensions of it. Gabbroic rocks were more abundant in the target stratigraphy than is apparent from the Apollo sample collection. Some pyroxene and plagiociase, but probably not much olivine, could be derived from feldspathic granulites, which are metamorphosed polymict breccias. Some mineral fragments are from previously unknown rocks. These include highly magnesian olivines (up to Fo(sub 94)), possibly volcanic in origin, that exacerbate the difficulty in explaining highly magnesian rocks in the lunar crust. It appears that some part of the lunar interior has an mg*(= 100 x Mg/(Mg/Fe) atomic) greater than the conventional bulk Moon value of 80-84. Other volcanic rocks, including mare basalts, and rapidly- cooled impact melt

  3. Microbial dolomite crusts from the carbonate platform off western India

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, V.P.; Kessarkar, P.M.; Krumbein, W.E.; Krajewski, K.P.; Schneider, R.J.

    Association of Sedimentologists, Sedimentology, 50, 819-830 Microbial dolomite crusts off western India 821 dolomite crusts [2 x 2·5 em to 3 x 0'5 em) and pebbles occur within these sediments. METHODS Thin sections of the crusts were studied petro graphically....E. (19S7) Holocene dolomitization Df supr

  4. 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.

  5. Visual lunar and planetary astronomy

    CERN Document Server

    Abel, Paul G

    2013-01-01

    With the advent of CCDs and webcams, the focus of amateur astronomy has to some extent shifted from science to art. The object of many amateur astronomers is now to produce “stunning images” that, although beautiful, are not intended to have scientific merit. Paul Abel has been addressing this issue by promoting visual astronomy wherever possible – at talks to astronomical societies, in articles for popular science magazines, and on BBC TV’s The Sky at Night.   Visual Lunar and Planetary Astronomy is a comprehensive modern treatment of visual lunar and planetary astronomy, showing that even in the age of space telescopes and interplanetary probes it is still possible to contribute scientifically with no more than a moderately priced commercially made astronomical telescope.   It is believed that imaging and photography is somehow more objective and more accurate than the eye, and this has led to a peculiar “crisis of faith” in the human visual system and its amazing processing power. But by anal...

  6. 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.

  7. Sir James Reid and the Death of Queen Victoria: An Early Model for End-of-Life Care.

    Science.gov (United States)

    Abrams, Robert C

    2015-12-01

    An appraisal of the last ten days of Queen Victoria's life, viewed primarily from the perspective of her personal physician, Sir James Reid, is presented. Sir James' clinical encounters with his patient and the Royal Family are examined to reveal his strategic and medical thinking and gauge his level of success in basic palliative aims. It was found that the lack of effective medical interventions, tensions within the Royal Family, the importance of his post to Sir James' professional career, and the political ramifications unavoidably connected with the illness of a head of state, all presented challenges to Reid's efforts to ease the physical and emotional pain of Queen Victoria's dying. Key features of Sir James' approach included reliance on physician-patient and physician-family relationships, emphasis on emotional support for the patient, and the careful selection of interventions for the family. In the first years of the 20th century, an era when the contemporary concepts of palliative care, hospice, and family dynamics did not exist, Sir James' management of the Queen's final illness suggested an early model for end-of-life care. By the end of Queen Victoria's life, Sir James was seen to have preserved his patient's comfort and dignity, at the same time advancing family and societal acceptance of the death of this matriarchal figure. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  8. 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.

  9. 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.

  10. Modeling Respiratory Toxicity of Authentic Lunar Dust

    Science.gov (United States)

    Santana, Patricia A.; James, John T.; Lam, Chiu-Wing

    2010-01-01

    The lunar expeditions of the Apollo operations from the 60 s and early 70 s have generated awareness about lunar dust exposures and their implication towards future lunar explorations. Critical analyses on the reports from the Apollo crew members suggest that lunar dust is a mild respiratory and ocular irritant. Currently, NASA s space toxicology group is functioning with the Lunar Airborne Dust Toxicity Assessment Group (LADTAG) and the National Institute for Occupational Safety and Health (NIOSH) to investigate and examine toxic effects to the respiratory system of rats in order to establish permissible exposure levels (PELs) for human exposure to lunar dust. In collaboration with the space toxicology group, LADTAG and NIOSH the goal of the present research is to analyze dose-response curves from rat exposures seven and twenty-eight days after intrapharyngeal instillations, and model the response using BenchMark Dose Software (BMDS) from the Environmental Protection Agency (EPA). Via this analysis, the relative toxicities of three types of Apollo 14 lunar dust samples and two control dust samples, titanium dioxide (TiO2) and quartz will be determined. This will be executed for several toxicity endpoints such as cell counts and biochemical markers in bronchoaveolar lavage fluid (BALF) harvested from the rats.

  11. Enrichment mechanisms of tellurium in ferromanganese crusts

    Science.gov (United States)

    Sakaguchi, A.; Sugiyama, T.; Usui, A.; Takahashi, Y.

    2012-04-01

    Marine ferromanganese crusts (FMCs) consist of iron (Fe) hydroxides and manganese (Mn) oxides with various minor and trace elements. Especially for tellurium (Te), which is recognized as one of the rare metals, it has been reported that this element is concentrated about 105 times in FMCs compared with earth's crust, and the host phase might be Fe (oxy)hydroxide (Hein et al., 2003). Actually, in our previous study, the high concentration of Te in very surface layers of FMCs was found from the top to halfway down of a seamount in the Pacific Ocean. However, the concentration of Te in surface layers through the seamount showed good correlation with that of Mn instead of Fe. In this study, we attempted to clarify the enrichment mechanism of Te in FMCs with some methods including X-ray absorption fine structure (XAFS) technique for synthesised /natural samples. Seventeen FMC samples were collected from the Takuyo-Daigo seamount, from 950 m (summit) to 3000 m in water depth, with hyper-dolphin (remotely operated vehicle) equipped with live video camera and manipulators. The growth rates of all FMC samples were estimated to be about 3 mm/Ma. Very surface layer (less than 1 mm) of all FMC was analyzed with XRD and XAFS to confirm the mineral composition and speciation of Te. Furthermore, to serve as an aid to clarify the adsorption mechanism of Te on FMCs, distribution coefficients (Kd) and oxidation states were determined through the adsorption experiments of Te(IV) and Te(VI) on ferrihydrite and δ-MnO2. In all the experiments, pH and ionic strength were adjusted to pH 7.5 and 0.7 M, respectively. The oxidation state of Te in water phase was determined with HPLC-ICP-MS. As for the analysis of oxidation and adsorption states on the solid phase, XAFS was employed. The major mineral composition of Fe and Mn had no significant variation through the water depth of Takuyo-Daigo seamount. The oxidation state of Te in all samples showed hexavalent, and there was no significant

  12. Bringing You the Moon: Lunar Education Efforts of the Center for Lunar Science and Education

    Science.gov (United States)

    Shaner, A. J.; Shupla, C.; Shipp, S.; Allen, J.; Kring, D. A.; Halligan, E.; LaConte, K.

    2012-01-01

    The Center for Lunar Science and Exploration (CLSE), a collaboration between the Lunar and Planetary Institute and NASA's Johnson Space Center, is one of seven member teams of the NASA Lunar Science Institute. In addition to research and exploration activities, the CLSE team is deeply invested in education and public outreach. Overarching goals of CLSE education are to strengthen the future science workforce, attract and retain students in STEM disciplines, and develop advocates for lunar exploration. The team's efforts have resulted in a variety of programs and products, including the creation of a variety of Lunar Traveling Exhibits and the High School Lunar Research Project, featured at http://www.lpi.usra.edu/nlsi/education/.

  13. The Lunar Transit Telescope (LTT) - An early lunar-based science and engineering mission

    Science.gov (United States)

    Mcgraw, John T.

    1992-01-01

    The Sentinel, the soft-landed lunar telescope of the LTT project, is described. The Sentinel is a two-meter telescope with virtually no moving parts which accomplishes an imaging survey of the sky over almost five octaves of the electromagnetic spectrum from the ultraviolet into the infrared, with an angular resolution better than 0.1 arsec/pixel. The Sentinel will incorporate innovative techniques of interest for future lunar-based telescopes and will return significant engineering data which can be incorporated into future lunar missions. The discussion covers thermal mapping of the Sentinel, measurement of the cosmic ray flux, lunar dust, micrometeoroid flux, the lunar atmosphere, and lunar regolith stability and seismic activity.

  14. Shallow Lunar Seismic Activity and the Current Stress State of the Moon

    Science.gov (United States)

    Watters, Thomas R.; Weber, Renee C.; Collins, Geoffrey C.; Johnson, Catherine L.

    2017-01-01

    A vast, global network of more than 3200 lobate thrust fault scarps has been revealed in high resolution Lunar Reconnaissance Orbiter Camera (LROC) images. The fault scarps are very young, less than 50 Ma, based on their small scale and crisp appearance, crosscutting relations with small-diameter impact craters, and rates of infilling of associated small, shallow graben and may be actively forming today. The population of young thrust fault scarps provides a window into the recent stress state of the Moon and offers insight into the origin of global lunar stresses. The distribution of orientations of the fault scarps is non-random, inconsistent with isotropic stresses from late-stage global contraction as the sole source of stress. Modeling shows that tidal stresses contribute significantly to the current stress state of the lunar crust. Tidal stresses (orbital recession and diurnal tides) superimposed on stresses from global contraction result in non-isotropic compressional stress and may produce thrust faults consistent with lobate scarp orientations. At any particular point on the lunar surface, peak compressive stress will be reached at a certain time in the diurnal cycle. Coseismic slip events on currently active thrust faults are expected to be triggered when peak stresses are reached. Analysis of the timing of the 28 the shallow moonquakes recorded by the Apollo seismic network shows that 19 indeed occur when the Moon is closer to apogee, while only 9 shallow events occur when the Moon is closer to perigee. Here we report efforts to refine the model for the current stress state of the Moon by investigating the contribution of polar wander. Progress on relocating the epicentral locations of the shallow moonquakes using an algorithm designed for sparse networks is also reported.

  15. 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.

  16. Characteristics and management options of crusting soils in a ...

    African Journals Online (AJOL)

    water infiltration and accelerated soil erosion resulting from soil crusting ... in a smallholder farming area of the Zambezi metamorphic belt in northern Zimbabwe ...... beans (Ricinus communi L.) in the northeastern region of Brazil. Soil and ...

  17. Russian Federation Snow Depth and Ice Crust Surveys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Russian Federation Snow Depth and Ice Crust Surveys, dataset DSI-9808, contains routine snow surveys that run throughout the cold season every 10 days (every five...

  18. Reduction of acrylamide content in bread crust by starch coating.

    Science.gov (United States)

    Liu, Jie; Liu, Xiaojie; Man, Yong; Liu, Yawei

    2018-01-01

    A technique of starch coating to reduce acrylamide content in bread crust was proposed. Bread was prepared in accordance with a conventional procedure and corn or potato starch coating was brushed on the surface of the fermented dough prior to baking. Corn starch coating caused a decrease in acrylamide of 66.7% and 77.1% for the outer and inner crust, respectively. The decrease caused by the potato starch coating was 68.4% and 77.4%, respectively. Starch coating reduced asparagine content significantly (43.4-82.9%; P coating, which effectively shortened the time span (4-8 min) over which acrylamide could form and accumulate. The present study demonstrates that starch coating could be a simple, effective and practical application for reducing acrylamide levels in bread crust without changing the texture and crust color of bread. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  19. Biosignatures of Hypersaline Environments (Salt Crusts) an Analog for Mars

    Science.gov (United States)

    Smith, H. D.; Duncan, A. G.; Davilla, A. F.; McKay, C. P.

    2016-05-01

    Halophilic ecosystems are models for life in extreme environments including planetary surfaces such as Mars. Our research focuses on biosignatures in a salt crusts and the detection of these biomarkers by ground and orbital assests.

  20. Strange Stars: Can Their Crust Reach the Neutron Drip Density?

    Institute of Scientific and Technical Information of China (English)

    Hai Fu; Yong-Feng Huang

    2003-01-01

    The electrostatic potential of electrons near the surface of static strange stars at zero temperature is studied within the frame of the MIT bag model. We find that for QCD parameters within rather wide ranges, if the nuclear crust on the strange star is at a density leading to neutron drip, then the electrostatic potential will be insufficient to establish an outwardly directed electric field, which is crucial for the survival of such a crust. If a minimum gap width of 200 fm is brought in as a more stringent constraint, then our calculations will completely rule out the possibility of such crusts. Therefore, our results argue against the existence of neutron-drip crusts in nature.

  1. Water sorption and transport in dry crispy bread crust

    NARCIS (Netherlands)

    Meinders, M.B.J.; Nieuwenhuijzen, van N.H.; Tromp, R.H.; Hamer, R.J.; Vliet, van T.

    2010-01-01

    Water sorption and dynamical properties of bread crust have been studied using gravimetric sorption experiments. Water uptake and loss were followed while relative humidity (RH) was stepwise in- or decreased (isotherm experiment) or varied between two adjusted values (oscillatory experiment).

  2. Formation and development of salt crusts on soil surfaces

    KAUST Repository

    Dai, Sheng; Shin, Hosung; Santamarina, Carlos

    2015-01-01

    The salt concentration gradually increases at the soil free surface when the evaporation rate exceeds the diffusive counter transport. Eventually, salt precipitates and crystals form a porous sodium chloride crust with a porosity of 0.43 ± 0.14. After detaching from soils, the salt crust still experiences water condensation and salt deliquescence at the bottom, brine transport across the crust driven by the humidity gradient, and continued air-side precipitation. This transport mechanism allows salt crust migration away from the soil surface at a rate of 5 μm/h forming salt domes above soil surfaces. The surface characteristics of mineral substrates and the evaporation rate affect the morphology and the crystal size of precipitated salt. In particular, substrate hydrophobicity and low evaporation rate suppress salt spreading.

  3. Yellow sorediate crusts called Caloplaca citrina in England

    Czech Academy of Sciences Publication Activity Database

    Powell, M.; Vondrák, Jan

    2012-01-01

    Roč. 2012, č. 110 (2012), s. 20-24 ISSN 0300-4562 Institutional research plan: CEZ:AV0Z60050516 Institutional support: RVO:67985939 Keywords : biodiversity * crytic species * sorediate crusts Subject RIV: EF - Botanics

  4. Breaking strain of neutron star crust and gravitational waves.

    Science.gov (United States)

    Horowitz, C J; Kadau, Kai

    2009-05-15

    Mountains on rapidly rotating neutron stars efficiently radiate gravitational waves. The maximum possible size of these mountains depends on the breaking strain of the neutron star crust. With multimillion ion molecular dynamics simulations of Coulomb solids representing the crust, we show that the breaking strain of pure single crystals is very large and that impurities, defects, and grain boundaries only modestly reduce the breaking strain to around 0.1. Because of the collective behavior of the ions during failure found in our simulations, the neutron star crust is likely very strong and can support mountains large enough so that their gravitational wave radiation could limit the spin periods of some stars and might be detectable in large-scale interferometers. Furthermore, our microscopic modeling of neutron star crust material can help analyze mechanisms relevant in magnetar giant flares and microflares.

  5. Formation and development of salt crusts on soil surfaces

    KAUST Repository

    Dai, Sheng

    2015-12-14

    The salt concentration gradually increases at the soil free surface when the evaporation rate exceeds the diffusive counter transport. Eventually, salt precipitates and crystals form a porous sodium chloride crust with a porosity of 0.43 ± 0.14. After detaching from soils, the salt crust still experiences water condensation and salt deliquescence at the bottom, brine transport across the crust driven by the humidity gradient, and continued air-side precipitation. This transport mechanism allows salt crust migration away from the soil surface at a rate of 5 μm/h forming salt domes above soil surfaces. The surface characteristics of mineral substrates and the evaporation rate affect the morphology and the crystal size of precipitated salt. In particular, substrate hydrophobicity and low evaporation rate suppress salt spreading.

  6. The origin of continental crust: Outlines of a general theory

    Science.gov (United States)

    Lowman, P. D., Jr.

    1985-01-01

    The lower continental crust, formerly very poorly understood, has recently been investigated by various geological and geophysical techniques that are beginning to yield a generally agreed on though still vague model (Lowman, 1984). As typified by at least some exposed high grade terranes, such as the Scottish Scourian complex, the lower crust in areas not affected by Phanerozoic orogeny or crustal extension appears to consist of gently dipping granulite gneisses of intermediate bulk composition, formed from partly or largely supracrustal precursors. This model, to the degree that it is correct, has important implications for early crustal genesis and the origin of continental crust in general. Most important, it implies that except for areas of major overthrusting (which may of course be considerable) normal superposition relations prevail, and that since even the oldest exposed rocks are underlain by tens of kilometers of sial, true primordial crust may still survive in the lower crustal levels (of. Phinney, 1981).

  7. The evolution of Mercury's crust: a global perspective from MESSENGER.

    Science.gov (United States)

    Denevi, Brett W; Robinson, Mark S; Solomon, Sean C; Murchie, Scott L; Blewett, David T; Domingue, Deborah L; McCoy, Timothy J; Ernst, Carolyn M; Head, James W; Watters, Thomas R; Chabot, Nancy L

    2009-05-01

    Mapping the distribution and extent of major terrain types on a planet's surface helps to constrain the origin and evolution of its crust. Together, MESSENGER and Mariner 10 observations of Mercury now provide a near-global look at the planet, revealing lateral and vertical heterogeneities in the color and thus composition of Mercury's crust. Smooth plains cover approximately 40% of the surface, and evidence for the volcanic origin of large expanses of plains suggests that a substantial portion of the crust originated volcanically. A low-reflectance, relatively blue component affects at least 15% of the surface and is concentrated in crater and basin ejecta. Its spectral characteristics and likely origin at depth are consistent with its apparent excavation from a lower crust or upper mantle enriched in iron- and titanium-bearing oxides.

  8. 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

  9. Zinnia Germination and Lunar Soil Amendment

    Science.gov (United States)

    Reese, Laura

    2017-01-01

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

  10. Adsorption of Hg on lunar samples

    International Nuclear Information System (INIS)

    Reed, G.W. Jr.; Jovanovic, S.

    1985-01-01

    Understanding the presence, migration mechanisms and trapping of indigneous gases and volatiles on the moon is the objective of this study. The rare gases Ar and Xe and highly volatile Hg 0 and Br 0 (and/or their compounds) have been determined to be present in the lunar regolith. Evidence for these elements in the moon was recently reviewed. Studies of the sorption behavior of Xe on lunar material have been carried out. We report here preliminary results of a study designed to rationalize the behavior of Hg in lunar material

  11. Polar lunar power ring: Propulsion energy resource

    Science.gov (United States)

    Galloway, Graham Scott

    1990-01-01

    A ring shaped grid of photovoltaic solar collectors encircling a lunar pole at 80 to 85 degrees latitude is proposed as the primary research, development, and construction goal for an initial lunar base. The polar Lunar Power Ring (LPR) is designed to provide continuous electrical power in ever increasing amounts as collectors are added to the ring grid. The LPR can provide electricity for any purpose indefinitely, barring a meteor strike. The associated rail infrastructure and inherently expandable power levels place the LPR as an ideal tool to power an innovative propulsion research facility or a trans-Jovian fleet. The proposed initial output range is 90 Mw to 90 Gw.

  12. Technicians work with Apollo 14 lunar sample material in Lunar Receiving Lab.

    Science.gov (United States)

    1971-01-01

    Glove handlers work with freshly opened Apollo 14 lunar sample material in modularized cabinets in the Lunar Receiving Laboratory at the Manned Spacecraft Center. The glove operator on the right starts to pour fine lunar material which he has just taken from a tote bag. This powdery sample was among the last to be revealed of the 90-odd pounds of material brought back to Earth by the Apollo 14 crewmen.

  13. Black manganese-rich crusts on a Gothic cathedral

    Science.gov (United States)

    Macholdt, Dorothea S.; Herrmann, Siegfried; Jochum, Klaus Peter; Kilcoyne, A. L. David; Laubscher, Thomas; Pfisterer, Jonas H. K.; Pöhlker, Christopher; Schwager, Beate; Weber, Bettina; Weigand, Markus; Domke, Katrin F.; Andreae, Meinrat O.

    2017-12-01

    Black manganese-rich crusts are found worldwide on the façades of historical buildings. In this study, they were studied exemplarily on the façade of the Freiburger Münster (Freiburg Minster), Germany, and measured in-situ by portable X-ray fluorescence (XRF). The XRF was calibrated to allow the conversion from apparent mass fractions to Mn surface density (Mn mass per area), to compensate for the fact that portable XRF mass fraction measurements from thin layers violate the assumption of a homogeneous measurement volume. Additionally, 200-nm femtosecond laser ablation-inductively coupled plasma-mass spectrometry (fs LA-ICP-MS) measurements, scanning transmission X-ray microscopy-near edge X-ray absorption fine structure spectroscopy (STXM-NEXAFS), Raman spectroscopy, and imaging by light microscopy were conducted to obtain further insight into the crust material, such as potential biogenic contributions, element distributions, trace element compositions, and organic functional groups. While black crusts of various types are present at many places on the minster's facade, crusts rich in Mn (with a Mn surface density >150 μg cm-2) are restricted to a maximum height of about 7 m. The only exceptions are those developed on the Renaissance-Vorhalle (Renaissance Portico) at a height of about 8 m. This part of the façade had been cleaned and treated with a silicon resin as recently as 2003. These crusts thus accumulated over a period of only 12 years. Yet, they are exceptionally Mn-rich with a surface density of 1200 μg cm-2, and therefore require an accumulation rate of about 100 μg cm-2 Mn per year. Trace element analyses support the theory that vehicle emissions are responsible for most of the Mn supply. Lead, barium, and zinc correlate with manganese, indicating that tire material, brake pads, and resuspended road dust are likely to be the element sources. Microscopic investigations show no organisms on or in the Mn-rich crusts. In contrast, Mn-free black

  14. Formation and Thermal Infrared Spectroscopy of Halite Crusts

    Science.gov (United States)

    Baldridge, A. M.; Christensen, P. R.

    2003-12-01

    Efflorescent salt crusts form as groundwater evaporates from capillary updraw of brine through sediment. Salts precipitate at the surface, coating and cementing the upper few layers of sediment. If enough brine is present to completely saturate and pond on top of the surface, halite will precipitate at the surface of the brine and settle out as layers of crystalline salt on top of the sediment. In playa environments, salts such as sulfates, carbonates and halides, and forms such crusts. In remote sensing studies of such surfaces, it is important to understand how the presence of salt crusts affects the spectral features of the surrounding sediment. This is especially true when the crusts form from a non-absorbing salt such as halite. Halite has been observed to exhibit unusual spectral properties in the thermal infrared. Specifically, granular mixtures of minerals with halite produced spectra in which the spectral features inverted form reflectivity, shifted to shorter wavelengths and the spectral contrast increased near absorption bands. However, in crusted surfaces, in which the halite cements, coats or overlays the mineral grains, the presence of halite has a different affect on the spectra. This work will examine the precipitation of halite and the formation of salt crusts for several sediment and brine mixtures. Laboratory measurements of thermal emission spectra for the crusts will be compared to previous studies for particulate mixtures of halite with minerals and well as to natural surface crusts. Detailed knowledge of such surfaces will allow for their discrimination and identification in terrestrial playa settings as well as in paleo-environments on Mars.

  15. 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.

  16. 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

  17. The origin of water in the primitive Moon as revealed by the lunar highlands samples

    Science.gov (United States)

    Barnes, Jessica J.; Tartèse, Romain; Anand, Mahesh; McCubbin, Francis M.; Franchi, Ian A.; Starkey, Natalie A.; Russell, Sara S.

    2014-03-01

    The recent discoveries of hydrogen (H) bearing species on the lunar surface and in samples derived from the lunar interior have necessitated a paradigm shift in our understanding of the water inventory of the Moon, which was previously considered to be a ‘bone-dry’ planetary body. Most sample-based studies have focused on assessing the water contents of the younger mare basalts and pyroclastic glasses, which are partial-melting products of the lunar mantle. In contrast, little attention has been paid to the inventory and source(s) of water in the lunar highlands rocks which are some of the oldest and most pristine materials available for laboratory investigations, and that have the potential to reveal the original history of water in the Earth-Moon system. Here, we report in-situ measurements of hydroxyl (OH) content and H isotopic composition of the mineral apatite from four lunar highlands samples (two norites, a troctolite, and a granite clast) collected during the Apollo missions. Apart from troctolite in which the measured OH contents in apatite are close to our analytical detection limit and its H isotopic composition appears to be severely compromised by secondary processes, we have measured up to ˜2200 ppm OH in the granite clast with a weighted average δD of ˜ -105±130‰, and up to ˜3400 ppm OH in the two norites (77215 and 78235) with weighted average δD values of -281±49‰ and -27±98‰, respectively. The apatites in the granite clast and the norites are characterised by higher OH contents than have been reported so far for highlands samples, and have H isotopic compositions similar to those of terrestrial materials and some carbonaceous chondrites, providing one of the strongest pieces of evidence yet for a common origin for water in the Earth-Moon system. In addition, the presence of water, of terrestrial affinity, in some samples of the earliest-formed lunar crust suggests that either primordial terrestrial water survived the aftermath

  18. Microbial Life of North Pacific Oceanic Crust

    Science.gov (United States)

    Schumann, G.; Koos, R.; Manz, W.; Reitner, J.

    2003-12-01

    Information on the microbiology of the deep subsurface is necessary in order to understand the factors controlling the rate and extent of the microbially catalyzed reactions that influence the geophysical properties of these environments. Drilling into 45-Ma oceanic basaltic crust in a deepwater environment during ODP Leg 200 provided a promising opportunity to explore the abundance, diversity and activity of micro-organisms. The combined use of culture-independent molecular phylogenetic analyses and enrichment culture techniques is an advantageous approach in investigating subsurface microbial ecosystems. Enrichment culture methods allow the evaluation of potential activities and functions. Microbiological investigations revealed few aerobic cultivable, in part hitherto unknown, micro-organisms in deep submarine sediments and basaltic lava flows. 16S rDNA sequencing of isolates from sediment revealed the next relatives to be members of the genera Halomonas, Pseudomonas, and Lactobacillus. Within the Pseudomonadaceae the closest relative is Acinetobacter sp., which was isolated from a deep subsurface environment. The next phylogenetical relatives within the Halomonadaceae are bacteria typically isolated from Soda lakes, which are considered as model of early life conditions. Interestingly, not only sediment bacteria could be obtained in pure culture. Aerobic strains could also be successfully isolated from the massive tholeiitic basalt layer at a depth of 76.16 mbsf (46 m below the sediment/basement contact). These particular isolates are gram-positive with low G+C content of DNA, phylogenetically affiliated to the phylum Firmicutes. The closest neighbors are e.g. a marine Bacillus isolated from the Gulf of Mexico and a low G+C gram-positive bacterium, which belongs to the microbial flora in the deepest sea mud of the Mariana Trench, isolated from a depth of 10,897 m. Based on the similarity values, the isolates represent hitherto undescribed species of the deep

  19. Lunar seismicity, structure, and tectonics

    Science.gov (United States)

    Lammlein, D. R.; Latham, G. V.; Dorman, J.; Nakamura, Y.; Ewing, M.

    1974-01-01

    Natural seismic events have been detected by the long-period seismometers at Apollo stations 16, 14, 15, and 12 at annual rates of 3300, 1700, 800, and 700, respectively, with peak activity at 13- to 14-day intervals. The data are used to describe magnitudes, source characteristics, and periodic features of lunar seismicity. In a present model, the rigid lithosphere overlies an asthenosphere of reduced rigidity in which present-day partial melting is probable. Tidal deformation presumably leads to critical stress concentrations at the base of the lithosphere, where moonquakes are found to occur. The striking tidal periodicities in the pattern of moonquake occurrence and energy release suggest that tidal energy is the dominant source of energy released as moonquakes. Thus, tidal energy is dissipated by moonquakes in the lithosphere and probably by inelastic processes in the asthenosphere.

  20. Fusion power from lunar resources

    International Nuclear Information System (INIS)

    Kulcinski, G.L.; Schmitt, H.H.

    1992-01-01

    This paper reports that the moon contains an enormous energy source in 3 He deposited by the solar wind. Fusion of only 100 kg of 3 He with deuterium in thermonuclear fusion power plants can produce > 1000 MW (electric) of electrical energy, and the lunar resource base is estimated at 1 x 10 9 kg of 3 He. This fuel can supply >1000 yr of terrestrial electrical energy demand. The methods for extracting this fuel and the other solar wind volatiles are described. Alternate uses of D- 3 He fusion in direct thrust rockets will enable more ambitious deep-space missions to be conducted. The capability of extracting hydrogen, water, nitrogen, and other carbon-containing molecules will open up the moon to a much greater level of human settlement than previously thought

  1. Radioactivity in returned lunar materials

    Science.gov (United States)

    1972-01-01

    The H-3, Ar-37, and Ar-39 radioactivities were measured at several depths in the large documented lunar rocks 14321 and 15555. The comparison of the Ar-37 activities from similar locations in rocks 12002, 14321, and 15555 gives direct measures of the amount of Ar-37 produced by the 2 November 1969 and 24 January 1971 solar flares. The tritium contents in the documented rocks decreased with increasing depths. The solar flare intensity averaged over 30 years obtained from the tritium depth dependence was approximately the same as the flare intensity averaged over 1000 years obtained from the Ar-37 measurements. Radioactivities in two Apollo 15 soil samples, H-3 in several Surveyor 3 samples, and tritium and radon weepage were also measured.

  2. Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) with Raman Imaging Applied to Lunar Meteorites.

    Science.gov (United States)

    Smith, Joseph P; Smith, Frank C; Booksh, Karl S

    2018-03-01

    Lunar meteorites provide a more random sampling of the surface of the Moon than do the returned lunar samples, and they provide valuable information to help estimate the chemical composition of the lunar crust, the lunar mantle, and the bulk Moon. As of July 2014, ∼96 lunar meteorites had been documented and ten of these are unbrecciated mare basalts. Using Raman imaging with multivariate curve resolution-alternating least squares (MCR-ALS), we investigated portions of polished thin sections of paired, unbrecciated, mare-basalt lunar meteorites that had been collected from the LaPaz Icefield (LAP) of Antarctica-LAP 02205 and LAP 04841. Polarized light microscopy displays that both meteorites are heterogeneous and consist of polydispersed sized and shaped particles of varying chemical composition. For two distinct probed areas within each meteorite, the individual chemical species and associated chemical maps were elucidated using MCR-ALS applied to Raman hyperspectral images. For LAP 02205, spatially and spectrally resolved clinopyroxene, ilmenite, substrate-adhesive epoxy, and diamond polish were observed within the probed areas. Similarly, for LAP 04841, spatially resolved chemical images with corresponding resolved Raman spectra of clinopyroxene, troilite, a high-temperature polymorph of anorthite, substrate-adhesive epoxy, and diamond polish were generated. In both LAP 02205 and LAP 04841, substrate-adhesive epoxy and diamond polish were more readily observed within fractures/veinlet features. Spectrally diverse clinopyroxenes were resolved in LAP 04841. Factors that allow these resolved clinopyroxenes to be differentiated include crystal orientation, spatially distinct chemical zoning of pyroxene crystals, and/or chemical and molecular composition. The minerals identified using this analytical methodology-clinopyroxene, anorthite, ilmenite, and troilite-are consistent with the results of previous studies of the two meteorites using electron microprobe

  3. 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.

  4. Lunar Plants Prototype for Moon Express

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of our project is to bring the first full life cycle to the moon: to demonstrate germination of plants in lunar gravity and radiation.The Moon Express...

  5. Educating the Next Generation of Lunar Scientists

    Science.gov (United States)

    Shaner, A. J.; Shipp, S. S.; Allen, J. S.; Kring, D. A.

    2010-12-01

    The Center for Lunar Science and Exploration (CLSE), a collaboration between the Lunar and Planetary Institute (LPI) and NASA’s Johnson Space Center (JSC), is one of seven member teams of the NASA Lunar Science Institute (NLSI). In addition to research and exploration activities, the CLSE team is deeply invested in education and outreach. In support of NASA’s and NLSI’s objective to train the next generation of scientists, CLSE’s High School Lunar Research Project is a conduit through which high school students can actively participate in lunar science and learn about pathways into scientific careers. The High School Lunar Research Project engages teams of high school students in authentic lunar research that envelopes them in the process of science and supports the science goals of the CLSE. Most high school students’ lack of scientific research experience leaves them without an understanding of science as a process. Because of this, each team is paired with a lunar scientist mentor responsible for guiding students through the process of conducting a scientific investigation. Before beginning their research, students undertake “Moon 101,” designed to familiarize them with lunar geology and exploration. Students read articles covering various lunar geology topics and analyze images from past and current lunar missions to become familiar with available lunar data sets. At the end of “Moon 101”, students present a characterization of the geology and chronology of features surrounding the Apollo 11 landing site. To begin their research, teams choose a research subject from a pool of topics compiled by the CLSE staff. After choosing a topic, student teams ask their own research questions, within the context of the larger question, and design their own research approach to direct their investigation. At the conclusion of their research, teams present their results and, after receiving feedback, create and present a conference style poster to a panel of

  6. Lunar Soil Particle Separator, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Soil Particle Separator (LSPS) is an innovative method to beneficiate soil prior to in-situ resource utilization (ISRU). The LSPS improves ISRU oxygen...

  7. Lunar Soil Particle Separator, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Soil Particle Separator (LSPS) is an innovative method to beneficiate soil prior to in-situ resource utilization (ISRU). The LSPS can improve ISRU oxygen...

  8. 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.

  9. Lunar Wireless Power Transfer Feasibility Study

    Energy Technology Data Exchange (ETDEWEB)

    Freid, Sheldon [National Security Technologies, LLC. (NSTec), Mercury, NV (United States); Popovic, Zoya [Univ. of Colorado, Boulder, CO (United States); Beckett, David R. [Independent Consultant; Anderson, Scott R. [Independent Consultant; Mann, Diana [Independent Consultant; Walker, Stuart [Independent Consultant

    2008-03-01

    This study examines the feasibility of a multi-kilowatt wireless radio frequency (RF) power system to transfer power between lunar base facilities. Initial analyses, show that wireless power transfer (WPT) systems can be more efficient and less expensive than traditional wired approaches for certain lunar and terrestrial applications. The study includes evaluations of the fundamental limitations of lunar WPT systems, the interrelationships of possible operational parameters, and a baseline design approach for a notionial system that could be used in the near future to power remote facilities at a lunar base. Our notional system includes state-of-the-art photovoltaics (PVs), high-efficiency microwave transmitters, low-mass large-aperture high-power transmit antennas, high-efficiency large-area rectenna receiving arrays, and reconfigurable DC combining circuitry.

  10. 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.)

  11. International Coordination of Lunar Polar Volatiles Exploration

    Science.gov (United States)

    Gruener, J. E.; Suzuki, N. H.; Carpenter, J. D.

    2015-10-01

    The International Space Exploration Coordination Group (ISECG) has established a study team to coordinate the worldwide interest in lunar polar volatiles, and in particular water ice, in an effort to stimulate cooperation and collaboration.

  12. 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.

  13. Production of Lunar Oxygen Through Vacuum Pyrolysis

    National Research Council Canada - National Science Library

    Matchett, John

    2006-01-01

    .... The vacuum pyrolysis method of oxygen production from lunar regolith presents a viable option for in situ propellant production because of its simple operation involving limited resources from earth...

  14. Learning Lunar Science Through the Selene Videogame

    Science.gov (United States)

    Reese, D. D.; Wood, C. A.

    2010-03-01

    Selene is a videogame to promote and assess learning of lunar science concepts. As players build and modify a Moon, Selene measures learning as it occurs. Selene is a model for 21st century learning and embedded assessment.

  15. 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.

  16. Modeling lunar calendar effects in taiwan

    OpenAIRE

    Jin-Lung Lin; Tian- Syh Liu

    2003-01-01

    The three most important Chinese holidays, Chinese New Year, the Dragon- boat Festival, and Mid-Autumn Holiday have dates determined by a lunar calendar and move between two solar months. Consumption, production, and other economic behavior in countries with large Chinese population including Taiwan are strongly affected by these holidays. For example, production accelerates before lunar new year, almost completely stops during the holidays and gradually rises to an average level after the ho...

  17. The influence of percutaneous nephrolithotomy on human systemic stress response, SIRS and renal function.

    Science.gov (United States)

    Shen, Pengfei; Wei, Wuran; Yang, Xiaochun; Zeng, Hao; Li, Xiong; Yang, Jie; Wang, Jia; Huang, Jiaoti

    2010-10-01

    The objective of this study is to investigate the influences of percutaneous nephrolithotomy (PNL) and open surgery nephrolithotomy on the systemic stress response, SIRS and renal function. Forty patients with kidney calculi were enrolled in the study. Twenty cases were randomized to the PNL group and the other twenty cases to the open surgery group. Levels of C-reactive protein (CRP), interleukin-6(IL-6), β(2)-microglobulin (β(2)-MG), respiration rate, heart rate, body temperature and white blood cell counts were examined. CRP and IL-6 were measured in all patients pre-operatively and on post-operative days 1, 3 and 6, respectively. There was significant difference in their pre- and post-operation levels (P PNL group and 12 cases in open surgery group; there was significant difference between the two groups (P 0.05). Urine β(2)-MG levels were also measured. There was significant difference between pre- and the first day post-PNL (P PNL (P > 0.05). There was significant difference between pre- and first and third day post-open surgery (P 0.05). There was significant difference between two groups at the first, third and sixth days (P PNL group and open surgery group to some extent. The degree of stress response of PNL is lower than that of open surgery, proving the advantages of PNL with reference to serum immunology. There were cases in both the groups with SIRS, but the degree of SIRS in PNL group was lesser than the other group. Both the groups have no obvious effect on glomerular filtration function after operation and have effect on renal tubular reabsorption in the early stage after operation; but the recovery of the PNL group is faster than the open surgery group. It is thus shown that PNL is much safer and more feasible and has lesser effect on renal function.

  18. Calorimetric studies of cryptogamic crust metabolism in response to temperature, water vapor, and liquid water

    Science.gov (United States)

    Dorothy A. Stradling; Tonya Thygerson; Bruce N. Smith; Lee D. Hansen; Richard S. Criddle; Rosemary L. Pendleton

    2001-01-01

    Cryptogamic crusts are communities composed of lichens, cyanobacteria, algae, mosses, and fungi. These integrated soil crusts are susceptible to disturbance, but if intact, appear to play a role in providing nutrients, especially nitrogen, to higher plants. It is not known how or under what conditions desert crusts can grow. Crust samples from localities on the...

  19. Effects of crust and cracks on simulated catchment discharge and soil loss

    NARCIS (Netherlands)

    Stolte, J.; Ritsema, C.J.; Roo, de A.P.J.

    1997-01-01

    Sealing, crusting and cracking of crusts of the soil surface has been observed in many parts of the world in areas with sandy, silty and loamy soils. Sealing and crust formation occurs under the influence of rain storm and drying weather. With prolonged drying, surface crusts might crack, leading to

  20. Snow and Ice Crust Changes over Northern Eurasia since 1966

    Science.gov (United States)

    Bulygina, O.; Groisman, P. Y.; Razuvaev, V.; Radionov, V.

    2009-12-01

    When temperature of snow cover reaches zero Celsius first time since its establishment, snowmelt starts. In many parts of the world this process can be lengthy. The initial amount of heat that “arrives” to the snowpack might be insufficient for complete snowmelt, during the colder nights re-freeze of the melted snow may occur (thus creating the ice crust layers), and a new cold front (or the departure of the warm front that initiated melt) can decrease temperatures below the freezing point again and stop the snowmelt completely. It well can be that first such snowmelt occurs in winter (thaw day) and for several months thereafter snowpack stays on the ground. However, even the first such melt initiates a process of snow metamorphosis on its surface changing snow albedo and generating snow crust as well as on its bottom generating ice crust. Once emerged, the crusts will not disappear until the complete snowmelt. Furthermore, these crusts have numerous pathways of impact on the wild birds and animals in the Arctic environment as well as on domesticated reindeers. In extreme cases, the crusts may kill some wild species and prevent reindeers’ migration and feeding. Ongoing warming in high latitudes created situations when in the western half of Eurasian continent days with thaw became more frequent. Keeping in mind potential detrimental impacts of winter thaws and associated with them snow/ice crust development, it is worthwhile to study directly what are the major features of snow and ice crust over Eurasia and what is their dynamics. For the purpose of this study, we employed the national snow survey data set archived at the Russian Institute for Hydrometeorological Information. The dataset has routine snow surveys run throughout the cold season each decade (during the intense snowmelt, each 5 days) at all meteorological stations of the former USSR, thereafter, in Russia since 1966. Prior to 1966 snow surveys are also available but the methodology of

  1. Distribution of Amino Acids in Lunar Regolith

    Science.gov (United States)

    Elsila, J. E.; Callahan, M. P.; Glavin, D. P.; Dworkin, J. P.; Noble, S. K.; Gibson, E. K., Jr.

    2014-01-01

    One of the most eagerly studied questions upon initial return of lunar samples was whether significant amounts of organic compounds, including amino acids, were present. Analyses during the 1970s produced only tentative and inconclusive identifications of indigenous amino acids. Those analyses were hampered by analytical difficulties including relative insensitivity to certain compounds, the inability to separate chiral enantiomers, and the lack of compound-specific isotopic measurements, which made it impossible to determine whether the detected amino acids were indigenous to the lunar samples or the results of contamination. Numerous advances have been made in instrumentation and methodology for amino acid characterization in extraterrestrial samples in the intervening years, yet the origin of amino acids in lunar regolith samples has been revisited only once for a single lunar sample, (3) and remains unclear. Here, we present initial data from the analyses of amino acid abundances in 12 lunar regolith samples. We discuss these abundances in the context of four potential amino acid sources: (1) terrestrial biological contamination; (2) contamination from lunar module (LM) exhaust; (3) derivation from solar windimplanted precursors; and (4) exogenous delivery from meteorites.

  2. Extraction of Water from Lunar Permafrost

    Science.gov (United States)

    Ethridge, Edwin C.; Kaukler, William

    2009-01-01

    Remote sensing indicates the presence of hydrogen rich regions associated with the lunar poles. The logical hypothesis is that there is cryogenically trapped water ice located in craters at the lunar poles. Some of the craters have been in permanent darkness for a billion years. The presence of water at the poles as well as other scientific advantages of a polar base, have influenced NASA plans for the lunar outpost. The lunar outpost has water and oxygen requirements on the order of 1 ton per year scaling up to as much as 5 tons per year. Microwave heating of the frozen permafrost has unique advantages for water extraction. Proof of principle experiments have successfully demonstrated that microwaves will couple to the cryogenic soil in a vacuum and the sublimed water vapor can be successfully captured on a cold trap. Dielectric property measurements of lunar soil simulant have been measured. Microwave absorption and attenuation in lunar soil simulant has been correlated with measured dielectric properties. Future work will be discussed.

  3. COMPASS Final Report: Lunar Communications Terminal (LCT)

    Science.gov (United States)

    Oleson, Steven R.; McGuire, Melissa L.

    2010-01-01

    The Lunar Communications Terminal (LCT) COllaborative Modeling and Parametric Assessment of Space Systems (COMPASS) session designed a terminal to provide communications between lunar South Pole assets, communications relay to/from these assets through an orbiting Lunar Relay Satellite (LRS) and navigation support. The design included a complete master equipment list, power requirement list, configuration design, and brief risk assessment and cost analysis. The Terminal consists of a pallet containing the communications and avionics equipment, surrounded by the thermal control system (radiator), an attached, deployable 10-m tower, upon which were mounted locally broadcasting and receiving modems and a deployable 1 m diameter Ka/S band dish which provides relay communications with the lunar relay satellites and, as a backup, Earth when it is in view. All power was assumed to come from the lunar outpost Habitat. Three LCT design options were explored: a stand-alone LCT servicing the manned outpost, an integrated LCT (into the Habitat or Lunar Lander), and a mini-LCT which provides a reduced level of communication for primarily robotic areas dealing as in situ resource utilization (ISRU) and remote science. Where possible all the designs assumed single fault tolerance. Significant mass savings were found when integrating the LCT into the Habitat or Lander but increases in costs occurred depending upon the level of man rating required for such designs.

  4. A class of stochastic delayed SIR epidemic models with generalized nonlinear incidence rate and temporary immunity

    Science.gov (United States)

    Fan, Kuangang; Zhang, Yan; Gao, Shujing; Wei, Xiang

    2017-09-01

    A class of SIR epidemic model with generalized nonlinear incidence rate is presented in this paper. Temporary immunity and stochastic perturbation are also considered. The existence and uniqueness of the global positive solution is achieved. Sufficient conditions guaranteeing the extinction and persistence of the epidemic disease are established. Moreover, the threshold behavior is discussed, and the threshold value R0 is obtained. We show that if R0 extinct with probability one, whereas if R0 > 1, then the system remains permanent in the mean.

  5. The threshold of a stochastic delayed SIR epidemic model with vaccination

    Science.gov (United States)

    Liu, Qun; Jiang, Daqing

    2016-11-01

    In this paper, we study the threshold dynamics of a stochastic delayed SIR epidemic model with vaccination. We obtain sufficient conditions for extinction and persistence in the mean of the epidemic. The threshold between persistence in the mean and extinction of the stochastic system is also obtained. Compared with the corresponding deterministic model, the threshold affected by the white noise is smaller than the basic reproduction number Rbar0 of the deterministic system. Results show that time delay has important effects on the persistence and extinction of the epidemic.

  6. Global stability of an SIR model with differential infectivity on complex networks

    Science.gov (United States)

    Yuan, Xinpeng; Wang, Fang; Xue, Yakui; Liu, Maoxing

    2018-06-01

    In this paper, an SIR model with birth and death on complex networks is analyzed, where infected individuals are divided into m groups according to their infection and contact between human is treated as a scale-free social network. We obtain the basic reproduction number R0 as well as the effects of various immunization schemes. The results indicate that the disease-free equilibrium is locally and globally asymptotically stable in some conditions, otherwise disease-free equilibrium is unstable and exists an unique endemic equilibrium that is globally asymptotically stable. Our theoretical results are confirmed by numerical simulations and a promising way for infectious diseases control is suggested.

  7. Sir Charles Bell (1774-1842) and his contributions to early neurosurgery.

    Science.gov (United States)

    Tubbs, R Shane; Riech, Sheryl; Verma, Ketan; Mortazavi, Martin M; Loukas, Marios; Benninger, Brion; Cohen-Gadol, Aaron A

    2012-03-01

    The renowned surgeon, neuroanatomist, and artist Sir Charles Bell not only impacted the lives of his peers through his creative endeavors and passion for art, but also sparked noteworthy breakthroughs in the field of neuroscience. His empathetic nature and zest for life enabled him to develop an early proclivity for patient care. As a result of his innovative findings regarding sensory and motor nerves and the anatomical makeup of the brain, he accepted some of the most prestigious awards and received an honorable reputation in society. Bell is recognized for his diligence, perseverance, and his remarkable contributions to surgery. The present review will explore his contributions to the discipline now known as neurosurgery.

  8. Dynamics analysis of SIR epidemic model with correlation coefficients and clustering coefficient in networks.

    Science.gov (United States)

    Zhang, Juping; Yang, Chan; Jin, Zhen; Li, Jia

    2018-07-14

    In this paper, the correlation coefficients between nodes in states are used as dynamic variables, and we construct SIR epidemic dynamic models with correlation coefficients by using the pair approximation method in static networks and dynamic networks, respectively. Considering the clustering coefficient of the network, we analytically investigate the existence and the local asymptotic stability of each equilibrium of these models and derive threshold values for the prevalence of diseases. Additionally, we obtain two equivalent epidemic thresholds in dynamic networks, which are compared with the results of the mean field equations. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Plume Mitigation: Soil Erosion and Lunar Prospecting Sensor Project

    Science.gov (United States)

    Metzger, Philip T.

    2014-01-01

    Demonstrate feasibility of the simplest, lowest-mass method of measuring density of a cloud of lunar soil ejected by rocket exhaust, using new math techniques with a small baseline laser/camera system. Focus is on exploring the erosion process that occurs when the exhaust plume of a lunar rocket impacts the regolith. Also, predicting the behavior of the lunar soil that would be blasted from a lunar landing/launch site shall assist in better design and protection of any future lunar settlement from scouring of structures and equipment. NASA is gathering experimental data to improve soil erosion models and understand how lunar particles enter the plume flow.

  10. Low-Energy Ballistic Transfers to Lunar Halo Orbits

    Science.gov (United States)

    Parker, Jeffrey S.

    2009-01-01

    Recent lunar missions have begun to take advantage of the benefits of low-energy ballistic transfers between the Earth and the Moon rather than implementing conventional Hohmann-like lunar transfers. Both Artemis and GRAIL plan to implement low-energy lunar transfers in the next few years. This paper explores the characteristics and potential applications of many different families of low-energy ballistic lunar transfers. The transfers presented here begin from a wide variety of different orbits at the Earth and follow several different distinct pathways to the Moon. This paper characterizes these pathways to identify desirable low-energy lunar transfers for future lunar missions.

  11. Lunar e-Library: A Research Tool Focused on the Lunar Environment

    Science.gov (United States)

    McMahan, Tracy A.; Shea, Charlotte A.; Finckenor, Miria; Ferguson, Dale

    2007-01-01

    As NASA plans and implements the Vision for Space Exploration, managers, engineers, and scientists need lunar environment information that is readily available and easily accessed. For this effort, lunar environment data was compiled from a variety of missions from Apollo to more recent remote sensing missions, such as Clementine. This valuable information comes not only in the form of measurements and images but also from the observations of astronauts who have visited the Moon and people who have designed spacecraft for lunar missions. To provide a research tool that makes the voluminous lunar data more accessible, the Space Environments and Effects (SEE) Program, managed at NASA's Marshall Space Flight Center (MSFC) in Huntsville, AL, organized the data into a DVD knowledgebase: the Lunar e-Library. This searchable collection of 1100 electronic (.PDF) documents and abstracts makes it easy to find critical technical data and lessons learned from past lunar missions and exploration studies. The SEE Program began distributing the Lunar e-Library DVD in 2006. This paper describes the Lunar e-Library development process (including a description of the databases and resources used to acquire the documents) and the contents of the DVD product, demonstrates its usefulness with focused searches, and provides information on how to obtain this free resource.

  12. 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.

  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; 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.

  14. Linking biological soil crust diversity to ecological functions

    Science.gov (United States)

    Glaser, Karin; Borchhardt, Nadine; Schulz, Karoline; Mikhailyuk, Tatiana; Baumann, Karen; Leinweber, Peter; Ulf, Karsten

    2016-04-01

    Biological soil crusts (BSCs) are an association of different microorganisms and soil particles in the top millimeters of the soil. They are formed by algae, cyanobacteria, microfungi, bacteria, bryophytes and lichens in various compositions. Our aim was to determine and compare the biodiversity of all occurring organisms in biogeographically different habitats, ranging from polar (both Arctic and Antarctic), subpolar (Scandinavia), temperate (Germany) to dry regions (Chile). The combination of microscopy and molecular techniques (next-generation sequencing) revealed highly diverse crust communities, whose composition clustered by region and correlates with habitat characteristics such as water content. The BSC biodiversity was then linked to the ecological function of the crusts. The functional role of the BSCs in the biogeochemical cycles of carbon, nitrogen and phosphorous is evaluated using an array of state of the art soil chemistry methods including Py-FIMS (pyrolysis field ionization mass spectrometry) and XANES (x-ray absorbance near edge structure). Total P as well as P fractions were quantified in all BSCs, adjacent soil underneath and comparable nearby soil of BSC-free areas revealing a remarkable accumulation of total phosphorous and a distinct pattern of P fractions in the crust. Further, we observed an indication of a different P-speciation composition in the crust compared with BSC-free soil. The data allow answering the question whether BSCs act as sink or source for these compounds, and how biodiversity controls the biogeochemical function of BSCs.

  15. Microenvironments and microscale productivity of cyanobacterial desert crusts

    Science.gov (United States)

    Garcia-Pichel, F.; Belnap, Jayne

    1996-01-01

    We used microsensors to characterize physicochemical microenvironments and photosynthesis occurring immediately after water saturation in two desert soil crusts from southeastern Utah, which were formed by the cyanobacteria Microcoleus vaginatus Gomont, Nostoc spp., and Scytonema sp. The light fields within the crusts presented steep vertical gradients in magnitude and spectral composition. Near-surface light-trapping zones were formed due to the scattering nature of the sand particles, but strong light attenuation resulted in euphotic zones only ca. 1 mm deep, which were progressively enriched in longer wavelengths with depth. Rates of gross photosynthesis (3.4a??9.4 mmol O2A?ma??2A?ha??1) and dark respiration (0.81a??3.1 mmol Oa??2A?ma??2A?ha??1) occurring within 1 to several mm from the surface were high enough to drive the formation of marked oxygen microenvironments that ranged from oxygen supersaturation to anoxia. The photosynthetic activity also resulted in localized pH values in excess of 10, 2a??3 units above the soil pH. Differences in metabolic parameters and community structure between two types of crusts were consistent with a successional pattern, which could be partially explained on the basis of the microenvironments. We discuss the significance of high metabolic rates and the formation of microenvironments for the ecology of desert crusts, as well as the advantages and limitations of microsensor-based methods for crust investigation.

  16. 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.

  17. Interpretation of Ferroan Anorthosite Ages and Implications for the Lunar Magma Ocean

    Science.gov (United States)

    Neal, C. R.; Draper, D. S.

    2017-01-01

    Ferroan Anorthosites (FANs) are considered to have purportedly crystallized directly from the lunar magma ocean (LMO) as a flotation crust. LMO modeling suggests that such anorthosites started to form only after greater than 70 percent of the LMO had crystallized. Recent age dates for FANs have questioned this hypothesis as they span too large of an age range. This means a younger age for the Moon-forming giant impact or the LMO hypothesis is flawed. However, FANs are notoriously difficult to age-date using the isochron method. We have proposed a mechanism for testing the LMO hypothesis through using plagioclase trace element abundances to calculate equilibrium liquids and compare them with LMO crystallization models. We now examine the petrography of the samples that have Sm-Nd (Samarium-Neodymium) age dates (Rb-Sr (Rubidium-Strontium) isotopic systematics may have been disturbed) and propose a relative way to age date FANs.

  18. [Sir Geoffrey Keynes 1887-1982. Surgical pioneer, medical historian, humanist].

    Science.gov (United States)

    Bergljung, Lars

    2005-01-01

    Sir Geoffrey Keynes (1887 - 1982), was a pioneer in the surgery of breast cancer and thymic deseases, n.b. in patients suffering from myastenia gravis. He strongly disapproved of the longstanding dogma of so called radical mastectomy in breast cancer, and advocated a more limited surgical approach, followed by radiation therapy. This was done more than fifty years before breastconserving surgery has become the therapy of choice and against considerable opposition from the surgical establishment of his days. He also became a pioneer in the surgical treatment of myastenia gravis by thymectomy, at a time when there was no real understanding of the pathophysiology of the disease and when considerable controversy existed as to the importance or non importance of concomitant tumour formation in the thymus. Besides being a busy surgeon Sir Geoffrey was a medical historian, writing the biography of among others William Harvey, a bibliographer with a special interest in the poet and artist William Blake and a bibliophil with a large book collection of great value to medical history.

  19. Investigating Environmentally Sustainable Transport Based on DALY weights and SIR Method

    Directory of Open Access Journals (Sweden)

    Hossein Nezamianpour Jahromi

    2012-09-01

    Full Text Available Accessibility is one of the main causes of well-being and growth in contemporary societies. Transportation is the backbone of accessibility systems that lead to the growth of economic and social networks and spatial dispersion of activities. Unfortunately, the adverse effects of transportation have a great impact on the natural and human environment. Since transportation is associated with fossil fuel combustion, it results in emissions of pollutants that cause damage to human health. To save the global eco-system, sustainable development has become an international priority. To deal with the sustainability of transportation systems is an important issue as testified by a growing number of initiatives framed to define and measure sustainability in transportation planning and infrastructure planning as well. The capability of environmental assessment as a sustainability instrument is well known. This study proposes a new approach to rank countries based on environmental sustainability development applying disability adjusted life year (DALY weights for transportation sector emissions. DALY weights consider actual impacts of pollutants on human health. By employing SIR method, a superiority and inferiority ranking method is presented for multiple criteria decision making, the sustainability ranking of a number of European countries is presented. Three various ranking methods extracted from SIR ranking method are discussed and the results and the correlation among them are demonstrated.

  20. New approaches to improve a WCDMA SIR estimator by employing different post-processing stages

    Directory of Open Access Journals (Sweden)

    Amnart Chaichoet

    2008-09-01

    Full Text Available For effective control of transmission power in WCDMA mobile systems, a good estimate of signal-to-interference ratio (SIR is needed. Conventionally, an adaptive SIR estimator employs a moving average (MA filter (Yoon et al., 2002 to encounter fading channel distortion. However, the resulting estimate seems to have high estimation error due to fluctuation in the channel variation. In this paper, an additional post-processing stage is proposed to improve the estimation accuracy by reducing the variation of the estimate. Four variations of post-processing stages, namely 1 a moving average (MA postfilter,2 an exponential moving average (EMA post-filter, 3 an IIR post-filter and 4 least-mean-squared (LMS adaptive post-filter, are proposed and their optimal performance in terms of root-mean-square error (RMSE are then compared by simulation. The results show the best comparable performance when the MA and LMS post-filter are used. However, the MA post-filter requires a lookup table of filter order for optimal performance at different channel conditions, while the LMS post-filter can be used conveniently without a lookup table.

  1. Medicinal use of earths and minerals from Hippocrates to Sir Hans Sloane and beyond.

    Science.gov (United States)

    Retsas, Spyros

    2012-12-01

    In 1931 two pharmaceutical drawers containing mineral specimens, belonging to Sir Hans Sloane, the 18th century collector, Royal Physician, President of the Royal Society and of the Royal College of Physicians of London, were found in the Department of Botany of the Natural History Museum (NHM) of London. The drawers, each divided into 49 compartments, contained a total of 107 mineral pharmaceutical specimens, some labelled as mercury or white arsenic. Their registration, identification with the Sloane Manuscript Catalogues and subsequent transfer to the Mineralogy department of the NHM where one of these drawers is now on public display, had been documented by 1935. In antiquity therapeutic empiricism attributed medicinal properties to animal products, plants and minerals, including the soil of specific geographic locations. This communication traces the medicinal use of certain earths and minerals, listed in Sir Hans Sloane's manuscript catalogues, to classical antiquity with a reference to Arsenic compounds, which in our time are finding application in the treatment of acute promyelocytic leukaemia and to Terra Lemnia, a celebrated antidote of repute spanning twenty centuries, also included in the Sloane collections.

  2. Influence of heat conductivity on the performance of RTV SIR coatings with different fillers

    Energy Technology Data Exchange (ETDEWEB)

    Siderakis, K [High Voltage Laboratory, Department of Electrical and Computer Engineering, University of Patras, GR-26110 Patras (Greece); Agoris, D [High Voltage Laboratory, Department of Electrical and Computer Engineering, University of Patras, Greece, GR-26500, Rion, Greece (Greece); Gubanski, S [High Voltage Laboratory, Department of Electric Power Engineering, Chalmers University of Technology, S-41296, Gothenburg (Sweden)

    2005-10-07

    Room temperature vulcanized silicone rubber (RTV SIR) coatings are employed in order to improve the pollution performance of high voltage ceramic insulators by imparting surface hydrophobicity. In this paper, the performance of three RTV SIR coatings containing different fillers is investigated in a salt-fog test. Alumina trihydrate (ATH) and silica are the fillers included in the formulation, aiming to increase the material endurance to the energy supplied by the surface electrical activity during periods of hydrophobicity loss. The primary action of these fillers is to increase the material heat conductivity, i.e. the amount of energy conducted to the substrate. In addition, in the case of ATH relief is also achieved due to particle decomposition. The results indicate that for the compositions commercially available, where low amounts of fillers are used, and under the conditions of the test, ATH filled coatings performed better than the silica filled ones. This is attributed to ATH decomposition which further relieves the material structure and therefore decelerates material aging.

  3. Ut Pictura Poesis : dialéctica entre palabras e imagen en Sir William Sterling Maxwell

    Directory of Open Access Journals (Sweden)

    Hilary Macartney

    2002-01-01

    Full Text Available En el presente artículo se analiza la estrecha relación entre la historia del arte de Sir William Stirling Maxwell, su biblioteca y su colección artística. Este vínculo encierra la clave para la comprensión de su excepcional aportación a la historiografía del arte español. Sus diversas actividades, como historiador del arte, coleccionista de libros y cuadros, y director de ediciones privadas de libros raros, fueron todas manifestaciones de su gran fascinación por el paralelo entre la literatura y el arte, la palabra y la imagen. Tal relación se encuentra incluso en el esquema decorativo de su biblioteca.This article examines the remarkable unity between Sir William Stirling Maxwell's art history, his library and his art collection and argües that this relationship is the key to understanding his unique contribution to scholarship of Spanish art. In particular, it will be shown that his actlvities as an art historian, bibliophile, art collector and editor of prívate editions of rare books were all expressions of his fascination with the relationship between literature and art in general, and more specifically between word and image. Even the decorative scheme of his library emphasised this relationship.

  4. Filtering authentic sepsis arising in the ICU using administrative codes coupled to a SIRS screening protocol.

    Science.gov (United States)

    Sudduth, Christopher L; Overton, Elizabeth C; Lyu, Peter F; Rimawi, Ramzy H; Buchman, Timothy G

    2017-06-01

    Using administrative codes and minimal physiologic and laboratory data, we sought a high-specificity identification strategy for patients whose sepsis initially appeared during their ICU stay. We studied all patients discharged from an academic hospital between September 1, 2013 and October 31, 2014. Administrative codes and minimal physiologic and laboratory criteria were used to identify patients at high risk of developing the onset of sepsis in the ICU. Two clinicians then independently reviewed the patient record to verify that the screened-in patients appeared to become septic during their ICU admission. Clinical chart review verified sepsis in 437/466 ICU stays (93.8%). Of these 437 encounters, only 151 (34.6%) were admitted to the ICU with neither SIRS nor evidence of infection and therefore appeared to become septic during their ICU stay. Selected administrative codes coupled to SIRS criteria and applied to patients admitted to ICU can yield up to 94% authentic sepsis patients. However, only 1/3 of patients thus identified appeared to become septic during their ICU stay. Studies that depend on high-intensity monitoring for description of the time course of sepsis require clinician review and verification that sepsis initially appeared during the monitoring period. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. The optimal dynamic immunization under a controlled heterogeneous node-based SIRS model

    Science.gov (United States)

    Yang, Lu-Xing; Draief, Moez; Yang, Xiaofan

    2016-05-01

    Dynamic immunizations, under which the state of the propagation network of electronic viruses can be changed by adjusting the control measures, are regarded as an alternative to static immunizations. This paper addresses the optimal dynamical immunization under the widely accepted SIRS assumption. First, based on a controlled heterogeneous node-based SIRS model, an optimal control problem capturing the optimal dynamical immunization is formulated. Second, the existence of an optimal dynamical immunization scheme is shown, and the corresponding optimality system is derived. Next, some numerical examples are given to show that an optimal immunization strategy can be worked out by numerically solving the optimality system, from which it is found that the network topology has a complex impact on the optimal immunization strategy. Finally, the difference between a payoff and the minimum payoff is estimated in terms of the deviation of the corresponding immunization strategy from the optimal immunization strategy. The proposed optimal immunization scheme is justified, because it can achieve a low level of infections at a low cost.

  6. A mixed SIR-SIS model to contain a virus spreading through networks with two degrees

    Science.gov (United States)

    Essouifi, Mohamed; Achahbar, Abdelfattah

    Due to the fact that the “nodes” and “links” of real networks are heterogeneous, to model computer viruses prevalence throughout the Internet, we borrow the idea of the reduced scale free network which was introduced recently. The purpose of this paper is to extend the previous deterministic two subchains of Susceptible-Infected-Susceptible (SIS) model into a mixed Susceptible-Infected-Recovered and Susceptible-Infected-Susceptible (SIR-SIS) model to contain the computer virus spreading over networks with two degrees. Moreover, we develop its stochastic counterpart. Due to the high protection and security taken for hubs class, we suggest to treat it by using SIR epidemic model rather than the SIS one. The analytical study reveals that the proposed model admits a stable viral equilibrium. Thus, it is shown numerically that the mean dynamic behavior of the stochastic model is in agreement with the deterministic one. Unlike the infection densities i2 and i which both tend to a viral equilibrium for both approaches as in the previous study, i1 tends to the virus-free equilibrium. Furthermore, since a proportion of infectives are recovered, the global infection density i is minimized. Therefore, the permanent presence of viruses in the network due to the lower-degree nodes class. Many suggestions are put forward for containing viruses propagation and minimizing their damages.

  7. 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.

  8. 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.

  9. The lunar tide in sporadic E

    Directory of Open Access Journals (Sweden)

    R. J. Stening

    1999-10-01

    Full Text Available It seems that the wind shear theory is accepted for the explanation of sporadic E at mid and low latitudes. Some examples from Arecibo are displayed to show this. The effect of lunar tides should then modify the wind-shear theory in a manner that yields the observed features of the lunar tide in the critical frequency foEs and the height h'Es of the sporadic E. This is shown to imply that the phase of the lunar tide in h'Es should be the same as the phase of the lunar tide in the eastward wind and that the phase of the lunar tide in foEs is three hours later. Hourly values of foEs, f bEs (the blanketing critical frequency and h'Es from several observatories are analysed for the lunar semidiurnal tide. It is found that the phase of the tide in foEs is often about 3 hours later than for h'Es in agreement with the theory. Seasonal variations in the tide are also examined with the statistically most significant results (largest amplitudes usually occurring in summer. After reviewing the many difficulties associated with determining the lunar tide in Es, both experimentally and theoretically, the analysed phase results are compared with what might be expected from Hagan's global scale wave model. Agreement is only fair (a success rate of 69% among the cases examined but probably as good as might be expected.Key words. Ionosphere (ionosphere – atmosphere interactions – ionospheric irregularities, Meteorology and atmosphere dynamics (waves and tides

  10. Lunar transportation scenarios utilising the Space Elevator.

    Science.gov (United States)

    Engel, Kilian A

    2005-01-01

    The Space Elevator (SE) concept has begun to receive an increasing amount of attention within the space community over the past couple of years and is no longer widely dismissed as pure science fiction. In light of the renewed interest in a, possibly sustained, human presence on the Moon and the fact that transportation and logistics form the bottleneck of many conceivable lunar missions, it is interesting to investigate what role the SE could eventually play in implementing an efficient Earth to Moon transportation system. The elevator allows vehicles to ascend from Earth and be injected into a trans-lunar trajectory without the use of chemical thrusters, thus eliminating gravity loss, aerodynamic loss and the need of high thrust multistage launch systems. Such a system therefore promises substantial savings of propellant and structural mass and could greatly increase the efficiency of Earth to Moon transportation. This paper analyzes different elevator-based trans-lunar transportation scenarios and characterizes them in terms of a number of benchmark figures. The transportation scenarios include direct elevator-launched trans-lunar trajectories, elevator launched trajectories via L1 and L2, as well as launch from an Earth-based elevator and subsequent rendezvous with lunar elevators placed either on the near or on the far side of the Moon. The benchmark figures by which the different transfer options are characterized and evaluated include release radius (RR), required delta v, transfer times as well as other factors such as accessibility of different lunar latitudes, frequency of launch opportunities and mission complexity. The performances of the different lunar transfer options are compared with each other as well as with the performance of conventional mission concepts, represented by Apollo. c2005 Elsevier Ltd. All rights reserved.

  11. 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.

  12. Lunar transportation scenarios utilising the Space Elevator

    Science.gov (United States)

    Engel, Kilian A.

    2005-07-01

    The Space Elevator (SE) concept has begun to receive an increasing amount of attention within the space community over the past couple of years and is no longer widely dismissed as pure science fiction. In light of the renewed interest in a, possibly sustained, human presence on the Moon and the fact that transportation and logistics form the bottleneck of many conceivable lunar missions, it is interesting to investigate what role the SE could eventually play in implementing an efficient Earth to Moon transportation system. The elevator allows vehicles to ascend from Earth and be injected into a trans-lunar trajectory without the use of chemical thrusters, thus eliminating gravity loss, aerodynamic loss and the need of high thrust multistage launch systems. Such a system therefore promises substantial savings of propellant and structural mass and could greatly increase the efficiency of Earth to Moon transportation. This paper analyzes different elevator-based trans-lunar transportation scenarios and characterizes them in terms of a number of benchmark figures. The transportation scenarios include direct elevator-launched trans-lunar trajectories, elevator-launched trajectories via L1 and L2, as well as launch from an Earth-based elevator and subsequent rendezvous with lunar elevators placed either on the near or on the far side of the Moon. The benchmark figures by which the different transfer options are characterized and evaluated include release radius (RR), required Δv, transfer times as well as other factors such as accessibility of different lunar latitudes, frequency of launch opportunities and mission complexity. The performances of the different lunar transfer options are compared with each other as well as with the performance of conventional mission concepts, represented by Apollo.

  13. Stress analysis and scaling studies of corium crusts

    International Nuclear Information System (INIS)

    Feng, Z.; Engelstad, R.L.; Lovell, E.G.; Corradini, M.L.

    1992-01-01

    In the event of a severe accident in a LWR, water may be input to cool the molten mixture of fuel and concrete. A number of structural models are developed and used to predict whether a crust will be formed and remain stable between the melt and water. Bending stresses and membrane stresses due to pressure loadings and the temperature differential are considered in the analyses to investigate the stability of the crust as a function of the time, thickness and span. The results from parametric studies show the conditions under which a crust could develop, and how such structural models could be used to determine scaling effects and provide correlations to prototypic accident situations. (orig.)

  14. Intensive Ammonia and Methane Oxidation in Organic Liquid Manure Crusts

    DEFF Research Database (Denmark)

    Nielsen, Daniel Aagren; Nielsen, Lars Peter; Schramm, Andreas

    methane oxidizing bacteria (MOB) and are known to accumulate nitrite and nitrate, indicating the presence of ammonia oxidizers (AOB). We have surveyed six manure tanks with organic covers to investigate the prevalence of MOB and AOB and to link the potential activity with physical and chemical aspects...... characterized with respect to O2 availability by in situ profiling with electrochemical microsensors. Results show that oxygen penetration increased from few micrometers up to several centimetres with crust age. AOB and ammonium oxidation are ubiquitously present in well-developed manure crusts whereas MOB were...... also CH4 emission mitigation, an organic surface crust can be effective if populations of MOB and AOB are allowed to build up....

  15. Entrainment in the inner crust of a neutron star

    International Nuclear Information System (INIS)

    Chamel, N.

    2004-01-01

    The inner crust of a neutron star, which is composed of a solid Coulomb lattice of nuclei immersed in a neutron super-fluid, is studied from both a macroscopic and a microscopic level. In the first part, we develop a non-relativistic but 4-dimensionally covariant formulation of the hydrodynamics of a perfect fluid mixture based on a variational principle. This formalism is applied to the description of neutron star crust as 2-fluid model, a neutron super-fluid and a plasma of nuclei and electrons coupled via non dissipative entrainment effects, whose microscopic evaluation is studied in a second part. Applying mean field methods beyond the Wigner-Seitz approximation, the Bragg scattering of dripped neutrons upon crustal nuclei lead to a 'mesoscopic' effective neutron mass, which unlike the 'microscopic' effective mass, takes very large values compared to the bare mass in the middle layers of the crust. (author)

  16. Fast Radio Bursts from the Collapse of Strange Star Crusts

    Science.gov (United States)

    Zhang, Yue; Geng, Jin-Jun; Huang, Yong-Feng

    2018-05-01

    Fast radio bursts (FRBs) are transient radio sources at cosmological distances. No counterparts in other bands have been observed for non-repeating FRBs. Here we suggest the collapse of strange star (SS) crusts as a possible origin for FRBs. SSs, which are composed of almost equal numbers of u, d, and s quarks, may be encapsulated by a thin crust of normal hadronic matter. When a SS accretes matter from its environment, the crust becomes heavier and heavier. It may finally collapse, leading to the release of a large amount of magnetic energy and plenty of electron/positron pairs on a very short timescale. Electron/positron pairs in the polar cap region of the SS can be accelerated to relativistic velocities, streaming along the magnetic field lines to form a thin shell. FRBs are produced by coherent emission from these electrons when the shell is expanding. Basic characteristics of observed FRBs can be explained in our model.

  17. What can be learned about the lunar mantle from the Gravity Recovery and Interior Laboratory (GRAIL)?

    Science.gov (United States)

    Zuber, M. T.; Smith, D. E.; Asmar, S. W.; Konopliv, A. S.; Lemoine, F. G.; Melosh, J.; Neumann, G. A.; Phillips, R. J.; Solomon, S. C.; Watkins, M. M.; Wieczorek, M. A.; Williams, J. G.; Andrews-Hanna, J. C.; Garrick-Bethell, I.; Head, J. W.; Kiefer, W. S.; Matsuyama, I.; McGovern, P. J.; Nimmo, F.; Soderblom, J. M.; Taylor, J.; Weber, R. C.; Goossens, S. J.; Kruizinga, G. L.; Mazarico, E.; Park, R. S.; Yuan, D.

    2013-12-01

    The Gravity Recovery and Interior Laboratory (GRAIL), a dual-spacecraft, gravity-mapping mission that is a component of NASA's Discovery Program, has successfully concluded its Primary and Extended Missions, and is currently in the science analysis phase. In order to safely navigate the dual spacecraft at an average altitude of 22.5 km above the lunar surface during the Extended Mission phase in the fall of 2012, and to derive the greatest information from the full mission data set, the focus had been on the production of gravitational fields with the highest-possible resolution. Spherical harmonic models of the Moon's gravitational field, produced by separate software systems at the Goddard Space Flight Center and the Jet Propulsion Laboratory, now include observations from both the Primary and Extended Missions. The highest-resolution models to date are to degree and order 900, corresponding to a spatial block size of 6 km, and are ideally suited to study the structure of the Moon's crust in extraordinary detail. GRAIL has achieved all measurement objectives for the Primary Mission, enabling all science investigations to be addressed. One of these investigations is to study the lunar hemispherical asymmetry, i.e., the difference between the nearside and farside. In this study we explore the nearside and farside mantle by isolating the long-wavelength gravity field. We accomplish this objective by removing plausible short-wavelength contributions from the crust that were based on the full resolution of high-degree and -order models, and by considering constraints from crustal compositions and volumes of mare basalt deposits. We localize the power spectral contributions of the nearside and farside to constrain lateral density variations, such as those associated with melting from the source regions of the mare basalts.

  18. Phosphatization Associated Features of Ferromanganese Crusts at Lemkein Seamount, Marshall Islands

    Science.gov (United States)

    Choi, J.; Lee, I.; Park, B. K.; Kim, J.

    2014-12-01

    Old layers of ferromanganese crusts, especially in the Pacific Ocean, have been affected by phosphatization. Ferromanganese crusts on Lemkein seamount in Marshall Islands also are phosphatized (3.3 to 4.2 wt % of P concentration). Furthermore, they have characteristic features that are different from other ferromanganese crusts. These features occur near the phosphorite, which were thought to fill the pore spaces of ferromanganese crusts. Inside the features, ferromanganese crusts are botryoidally precipitated from the round-boundary. The features of the phosphatized lower crusts of Lemkein seamount are observed using microscope and SEM. Elemental compositions of the selected samples were analyzed by SEM-EDS. Based on the observation and analysis of samples, three characteristic structures are identified: (1) phosphate-filled circles, (2) tongue-shaped framboidal crust, and (3) massive framboidal crust. The phosphate-filled circles are mostly composed of phosphorite, and they include trace fossils such as foraminifera. Phosphatized ferromanganese crusts exist at the boundary of this structure. The tongue-shaped crust is connected with the lips downward, and ferromanganese crusts inside the tongue show distinct growth rim. The massive framboidal crust is located below the tongue. Ferromanganese crusts in the massive framboidal crust are enveloped by phosphate, and some of the crusts are phosphatized. Around the structures, Mn oxide phase is concentrated as a shape of corona on BSE image. All of the structures are in the phosphatized crusts that show columnar growth of ferromanganese crusts and have sub-parallel lamination. These observation and chemical analysis of the ferromanganese crusts can provide a clue of diagenetic processes during the formation of ferromanganese crusts.

  19. Quantitative measurement of Y90 brehmmstrahlung images after of Y90 Sir-Spheres implantation to assess lung shunting

    International Nuclear Information System (INIS)

    Forwood, Nicholas J.; Pocock, Nicholas; Shin, Jane; Young, Andy M; Szeto, Edwin R.

    2009-01-01

    Full text: Background: In clinical practice the dose of Y 9 0 Sir-Spheres is calculated using a pre injection of Tc 9 9 m MAA. There is however a potential difference due to the different properties of Tc 9 9 m MAA and Y 9 0 Sir-Spheres. We assessed the concordance of lung shunting of Y 9 0 Sir-Spheres estimated using Y 9 0 Bremsstrahlung imaging, compared to shunting assessed using Tc 9 9 m MAA. Methods: 15 Patients were evaluated using 150-200 MBq of Tc 9 9 m MAA injected into the hepatic artery under angiographic guidance. Whole body images were acquired using a LEAP collimator (window of 140 kEv+/-10%). The patients were subsequently treated with Y 9 0 Sir-Spheres. After microspheres injection, whole body brehmsstrahlung images were acquired using a medium energy collimator (window settings of 75 kEv +/- 20%). Tc 9 9 m MAA images were paired with their corresponding bremsstrahlung image and lung shunting in the stu ides calculated simultaneously. Each paired dataset was analyzed by 5 operators. Results: The mean lung shunting for Tc 9 9 m MAA acquisition was 3.32% (SD 2.03) which was significantly lower than the lung shunting using the Y 9 0 acquisitions: mean 16.19% (SD of 6.43). The Pearson coefficient was r = 0.62 (p 9 0 Sir-Spheres bremsstrahlung imaging is higher than that calculated by Tc 9 9 m MAA imaging. The relationship is not sufficiently strong to use bremsstahlung imaging to retrospectively quantify the lung-to-liver shunting as indicated using Tc 9 9 M AA. Further studies are underway to assess the reliability of Tc 9 9 m MAA lung uptake calculations in determining the dose of Y 9 0 Sir-Spheres.

  20. Leveraging Virtual Reality for the Benefit of Lunar Exploration

    Science.gov (United States)

    McCandless, R. S.; Burke, E. D.; McGinley, V. T.

    2017-10-01

    Virtual reality (VR) and related technologies will assist scientists with lunar exploration and public engagement. We will present the future exponential impact of VR on lunar activities over the coming decades.

  1. Lunar All-Terrain Utility Vehicle for EVA, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — ProtoInnovations, LLC proposes to develop a new type of planetary rover called a Lunar All-terrain Utility Vehicle ("Lunar ATV") to assist extra-vehicular activities...

  2. 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...

  3. USArray Imaging of Continental Crust in the Conterminous United States

    Science.gov (United States)

    Ma, Xiaofei; Lowry, Anthony R.

    2017-12-01

    The thickness and bulk composition of continental crust provide important constraints on the evolution and dynamics of continents. Crustal mineralogy and thickness both may influence gravity anomalies, topographic elevation, and lithospheric strength, but prior to the inception of EarthScope's USArray, seismic measurements of crustal thickness and properties useful for inferring lithology are sparse. Here we improve upon a previously published methodology for joint inversion of Bouguer gravity anomalies and seismic receiver functions by using parameter space stacking of cross correlations of modeled synthetic and observed receiver functions instead of standard H-κ amplitude stacking. The new method is applied to estimation of thickness and bulk seismic velocity ratio, vP/vS, of continental crust in the conterminous United States using USArray and other broadband network data. Crustal thickness variations are reasonably consistent with those found in other studies and show interesting relationships to the history of North American continental formation. Seismic velocity ratios derived in this study are more robust than in other analyses and hint at large-scale variations in composition of continental crust. To interpret the results, we model the pressure-/temperature-dependent thermodynamics of mineral formation for various crustal chemistries, with and without volatile constituents. Our results suggest that hydration lowers bulk crustal vP/vS and density and releases heat in the shallow crust but absorbs heat in the lowermost crust (where plagioclase breaks down to pyroxene and garnet resulting in higher seismic velocity). Hence, vP/vS variations may provide a useful proxy for hydration state in the crust.

  4. 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.

  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. Crust and mantle of the gulf of Mexico

    Science.gov (United States)

    Moore, G.W.

    1972-01-01

    A SEEMING paradox has puzzled investigators of the crustal structure of the Gulf of Mexico since Ewing et al.1 calculated that a unit area of the rather thick crust in the gulf contains less mass than does a combination of the crust and enough of the upper mantle to make a comparable thickness in the Atlantic Ocean. They also noted that the free-air gravity of the gulf is essentially normal and fails by a large factor to be low enough to reflect the mass difference that they calculated. We propose a solution to this problem. ?? 1972 Nature Publishing Group.

  7. Impulsive vaccination and dispersal on dynamics of an SIR epidemic model with restricting infected individuals boarding transports

    Science.gov (United States)

    Jiao, Jianjun; Cai, Shaohong; Li, Limei

    2016-05-01

    To understand the effect of impulsive vaccination and restricting infected individuals boarding transports on disease spread, we establish an SIR model with impulsive vaccination, impulsive dispersal and restricting infected individuals boarding transports. This SIR epidemic model for two regions, which are connected by transportation of non-infected individuals, portrays the evolvement of diseases. We prove that all solutions of the investigated system are uniformly ultimately bounded. We also prove that there exists globally asymptotically stable infection-free boundary periodic solution. The condition for permanence is discussed. It is concluded that the approach of impulsive vaccination and restricting infected individuals boarding transports provides reliable tactic basis for preventing disease spread.

  8. L’économie politique du désir dans le rituel et le militantisme au SriLanka

    Directory of Open Access Journals (Sweden)

    Wim Van Daele

    2013-03-01

    Full Text Available Le désir est au cœur des interactions complexes entre le développement et la religion. Cet article examine ses différentes expressions, comme étant une des préoccupations fondamentales de nombreuses religions, qui motivent à la fois le développement et les alternatives au développement. Au SriLanka, face au changement social, la forme néolibérale et mondialisée du développement est comprise et réinterprétée à travers des idiomes et des formations locales du désir. L’économie néolibérale cultive le désir et mène à un accroissement présumé de la présence des preta (fantômes affamés et avides qui se manifestent parfois au moment de la mort d’une personne. Les fantômes affamés, en tant que formations fétichisées du désir, trouvent un écho chez les consommateurs et les entrepreneurs, qui montrent unappétit insatiable vis-à-vis d’une richesse matérielle en constante croissance. Ainsi, l’apaisement ritualisé des fantômes affamés et le militantisme social de groupes tels que le Movement for National Land and Agricultural Reform (MONLAR sont clairement liés par leur préoccupation mutuelle face à l’insécurité existentielle des êtres humains et non humains, causée par un désir excessif et déséquilibré. L’action rituelle et le militantisme social divergent toutefois dans la formulation explicite de leurs préoccupations spécifiques concernant le désir. Le rituel matérialise et condense l’angoisse liée au désir, alors que le militantisme social décrit la fétichisation du désir en termes économiques, politiques et scientifiques plus abstraits.

  9. 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,...

  10. Recreating Galileo's 1609 Discovery of Lunar Mountains

    Science.gov (United States)

    Pasachoff, Jay M.; Needham, Paul S.; Wright, Ernest T.; Gingerich, Owen

    2014-11-01

    The question of exactly which lunar features persuaded Galileo that there were mountains on the moon has not yet been definitively answered; Galileo was famously more interested in the concepts rather than the topographic mapping in his drawings and the eventual engravings. Since the pioneering work of Ewen Whitaker on trying to identify which specific lunar-terminator features were those that Galileo identified as mountains on the moon in his 1609 observations reported in his Sidereus Nuncius (Venice, 1610), and since the important work on the sequence of Galileo's observations by Owen Gingerich (see "The Mystery of the Missing 2" in Galilaeana IX, 2010, in which he concludes that "the Florentine bifolium sheet [with Galileo's watercolor images] is Galileo's source for the reworked lunar diagrams in Sidereus Nuncius"), there have been advances in lunar topographical measurements that should advance the discussion. In particular, one of us (E.T.W.) at the Scientific Visualization Studio of NASA's Goddard Space Flight Center has used laser-topography from NASA's Lunar Reconnaissance Orbiter to recreate what Galileo would have seen over a sequence of dates in late November and early December 1609, and provided animations both at native resolution and at the degraded resolution that Galileo would have observed with his telescope. The Japanese Kaguya spacecraft also provides modern laser-mapped topographical maps.

  11. 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.

  12. Ocular toxicity of authentic lunar dust.

    Science.gov (United States)

    Meyers, Valerie E; Garcìa, Hector D; Monds, Kathryn; Cooper, Bonnie L; James, John T

    2012-07-20

    Dust exposure is a well-known occupational hazard for terrestrial workers and astronauts alike and will continue to be a concern as humankind pursues exploration and habitation of objects beyond Earth. Humankind's limited exploration experience with the Apollo Program indicates that exposure to dust will be unavoidable. Therefore, NASA must assess potential toxicity and recommend appropriate mitigation measures to ensure that explorers are adequately protected. Visual acuity is critical during exploration activities and operations aboard spacecraft. Therefore, the present research was performed to ascertain the ocular toxicity of authentic lunar dust. Small (mean particle diameter = 2.9 ± 1.0 μm), reactive lunar dust particles were produced by grinding bulk dust under ultrapure nitrogen conditions. Chemical reactivity and cytotoxicity testing were performed using the commercially available EpiOcularTM assay. Subsequent in vivo Draize testing utilized a larger size fraction of unground lunar dust that is more relevant to ocular exposures (particles lunar dust was minimally irritating. Minor irritation of the upper eyelids was noted at the 1-hour observation point, but these effects resolved within 24 hours. In addition, no corneal scratching was observed using fluorescein stain. Low-titanium mare lunar dust is minimally irritating to the eyes and is considered a nuisance dust for ocular exposure. No special precautions are recommended to protect against ocular exposures, but fully shielded goggles may be used if dust becomes a nuisance.

  13. Design of a lunar oxygen production plant

    Science.gov (United States)

    Radhakrishnan, Ramalingam

    1990-01-01

    To achieve permanent human presence and activity on the moon, oxygen is required for both life support and propulsion. Lunar oxygen production using resources existing on the moon will reduce or eliminate the need to transport liquid oxygen from earth. In addition, the co-products of oxygen production will provide metals, structural ceramics, and other volatile compounds. This will enable development of even greater self-sufficiency as the lunar outpost evolves. Ilmenite is the most abundant metal-oxide mineral in the lunar regolith. A process involving the reaction of ilmenite with hydrogen at 1000 C to produce water, followed by the electrolysis of this water to provide oxygen and recycle the hydrogen has been explored. The objective of this 1990 Summer Faculty Project was to design a lunar oxygen-production plant to provide 5 metric tons of liquid oxygen per year from lunar soil. The results of this study describe the size and mass of the equipment, the power needs, feedstock quantity and the engineering details of the plant.

  14. Community Report and Recommendations from International Lunar Exploration Working Group (ILEWG)

    Science.gov (United States)

    Foing, Bernard H.

    2016-07-01

    and Resource Utilisation; Infrastructure and Human aspects; Moon, Space and Society. The latest technical achievements and results of recent missions (SMART-1, Kaguya, Chang'E1, Chandrayaan-1, LCROSS and LRO) were discussed at a plenary panel and technical sessions, with the Lunar Reconnaissance Orbiter (LRO) still in operation. Chang'E1 has generated many useful results for the community. Four plenary panel sessions were conducted: 1. What are the plans? 2. New mission results; 3. From space stations and robotic precursors to lunar bases; 4. Moon, Space, Society The participants summarised their findings, discussions and recommend o continue efforts by agencies and the community on previous ICEUM recommendations, and the continuation of the ILEWG forum, technical groups activities and pilot projects. 1. Science and exploration - World-wide access to raw and derived (geophysical units) data products using consistent formats and coordinate systems will maximize return on investment. We call to develop and implement plans for generation, validation, and release of these data products. Data should be made available for scientific analysis and supporting the development and planning of future missions - There are still Outstanding Questions: Structure and composition of crust, mantle, and core and implications for the origin and evolution of the Earth-Moon system; Timing, origin, and consequences of late heavy bombardment; Impact processes and regolith evolution; Nature and origin of volatile emplacement; Implications for resource utilization. These questions require international cooperation and sharing of results in order to be answered in a cost-effective manner - Ground truth information on the lunar far side is missing and needed to address many important scientific questions, e.g. with a sample return from South Pole- Aitken Basin - Knowledge of the interior is poor relative to the surface, and is needed to address a number of key questions, e.g. with International

  15. Influence of the Choice of Lunar Gravity Model on Orbit Determination for Lunar Orbiters

    Directory of Open Access Journals (Sweden)

    Young-Rok Kim

    2018-01-01

    Full Text Available We examine the influence of the lunar gravity model on the orbit determination (OD of a lunar orbiter operating in a 100 km high, lunar polar orbit. Doppler and sequential range measurements by three Deep Space Network antennas and one Korea Deep Space Antenna were used. For measurement simulation and OD analysis, STK11 and ODTK6 were utilized. GLGM2, LP100K, LP150Q, GRAIL420A, and GRAIL660B were used for investigation of lunar gravity model selection effect. OD results were assessed by position and velocity uncertainties with error covariance and an external orbit comparison using simulated true orbit. The effect of the lunar gravity models on the long-term OD, degree and order level, measurement-acquisition condition, and lunar altitude was investigated. For efficiency verification, computational times for the five lunar gravity models were compared. Results showed that significant improvements to OD accuracy are observed by applying a GRAIL-based model; however, applying a full order and degree gravity modeling is not always the best strategy, owing to the computational burden. Consequently, we consider that OD using GRAIL660B with 70 × 70 degree and order is the most efficient strategy for mission preanalysis. This study provides useful guideline for KPLO OD analysis during nominal mission operation.

  16. Introduction of JAXA Lunar and Planetary Exploration Data Analysis Group: Landing Site Analysis for Future Lunar Polar Exploration Missions

    Science.gov (United States)

    Otake, H.; Ohtake, M.; Ishihara, Y.; Masuda, K.; Sato, H.; Inoue, H.; Yamamoto, M.; Hoshino, T.; Wakabayashi, S.; Hashimoto, T.

    2018-04-01

    JAXA established JAXA Lunar and Planetary Exploration Data Analysis Group (JLPEDA) at 2016. Our group has been analyzing lunar and planetary data for various missions. Here, we introduce one of our activities.

  17. 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

  18. The Near Side : Regional Lunar Gravity Field Determination

    NARCIS (Netherlands)

    Goossens, S.

    2005-01-01

    In the past ten years the Moon has come fully back into focus, resulting in missions such as Clementine and Lunar Prospector. Data from these missions resulted in a boost in lunar gravity field modelling. Until this date, the lunar gravity field has mainly been expressed in a global representation,

  19. Lunar Cycles, Catchability of Penaeid Shrimps and Implications for ...

    African Journals Online (AJOL)

    Keywords: Penaeidae, fishing effort, lunar phases, profitability, spatial closures. ... closures during periods of the lunar cycle with predictably low catch-per- ... each lunar phase and month using two-way ANOVA. ... shrimps, for which the CPUE declined throughout the fishing season ... (Garcia, 1988) and abundance of.

  20. Apollo 16 Lunar Module 'Orion' at the Descartes landing site

    Science.gov (United States)

    1972-01-01

    The Apollo 16 Lunar Module 'Orion' is part of the lunar scene at the Descartes landing site, as seen in the reproduction taken from a color television transmission made by the color TV camera mounted on the Lunar Roving Vehicle. Note the U.S. flag deployed on the left. This picture was made during the second Apollo 16 extravehicular activity (EVA-2).

  1. 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.

  2. 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.

  3. Lunar impact basins revealed by Gravity Recovery and Interior Laboratory measurements.

    Science.gov (United States)

    Neumann, Gregory A; Zuber, Maria T; Wieczorek, Mark A; Head, James W; Baker, David M H; Solomon, Sean C; Smith, David E; Lemoine, Frank G; Mazarico, Erwan; Sabaka, Terence J; Goossens, Sander J; Melosh, H Jay; Phillips, Roger J; Asmar, Sami W; Konopliv, Alexander S; Williams, James G; Sori, Michael M; Soderblom, Jason M; Miljković, Katarina; Andrews-Hanna, Jeffrey C; Nimmo, Francis; Kiefer, Walter S

    2015-10-01

    Observations from the Gravity Recovery and Interior Laboratory (GRAIL) mission indicate a marked change in the gravitational signature of lunar impact structures at the morphological transition, with increasing diameter, from complex craters to peak-ring basins. At crater diameters larger than ~200 km, a central positive Bouguer anomaly is seen within the innermost peak ring, and an annular negative Bouguer anomaly extends outward from this ring to the outer topographic rim crest. These observations demonstrate that basin-forming impacts remove crustal materials from within the peak ring and thicken the crust between the peak ring and the outer rim crest. A correlation between the diameter of the central Bouguer gravity high and the outer topographic ring diameter for well-preserved basins enables the identification and characterization of basins for which topographic signatures have been obscured by superposed cratering and volcanism. The GRAIL inventory of lunar basins improves upon earlier lists that differed in their totals by more than a factor of 2. The size-frequency distributions of basins on the nearside and farside hemispheres of the Moon differ substantially; the nearside hosts more basins larger than 350 km in diameter, whereas the farside has more smaller basins. Hemispherical differences in target properties, including temperature and porosity, are likely to have contributed to these different distributions. Better understanding of the factors that control basin size will help to constrain models of the original impactor population.

  4. Ion microprobe mass analysis of plagioclase from 'non-mare' lunar samples

    Science.gov (United States)

    Meyer, C., Jr.; Anderson, D. H.; Bradley, J. G.

    1974-01-01

    The ion microprobe was used to measure the composition and distribution of trace elements in lunar plagioclase, and these analyses are used as criteria in determining the possible origins of some nonmare lunar samples. The Apollo 16 samples with metaclastic texture and high-bulk trace-element contents contain plagioclase clasts with extremely low trace-element contents. These plagioclase inclusions represent unequilibrated relicts of anorthositic, noritic, or troctolitic rocks that have been intermixed as a rock flour into the KREEP-rich matrix of these samples. All of the plagioclase-rich inclusions which were analyzed in the KREEP-rich Apollo 14 breccias were found to be rich in trace elements. This does not seem to be consistent with the interpretation that the Apollo 14 samples represent a pre-Imbrium regolith, because such an ancient regolith should have contained many plagioclase clasts with low trace-element contents more typical of plagioclase from the pre-Imbrium crust. Ion-microprobe analyses for Ba and Sr in large plagioclase phenocrysts in 14310 and 68415 are consistent with the bulk compositions of these rocks and with the known distribution coefficients for these elements. The distribution coefficient for Li (basaltic liquid/plagioclase) was measured to be about 2.

  5. Crustal Stretching Style and Lower Crust Flow of the South China Sea Northern Margin

    Science.gov (United States)

    Bai, Y.; Dong, D.; Runlin, D.

    2017-12-01

    There is a controversy about crustal stretching style of the South China Sea (SCS) northern margin mainly due to considerable uncertainty of stretching factor estimation, for example, as much as 40% of upper crust extension (Walsh et al., 1991) would be lost by seismic profiles due to poor resolution. To discover and understand crustal stretching style and lower crustal flow on the whole, we map the Moho and Conrad geometries based on gravity inversion constrained by deep seismic profiles, then according to the assumption of upper and lower crust initial thickness, upper and lower crust stretching factors are estimated. According to the comparison between upper and lower crust stretching factors, the SCS northern margin could be segmented into three parts, (1) sediment basins where upper crust is stretched more than lower crust, (2) COT regions where lower crust is stretched more than upper crust, (3) other regions where the two layers have similar stretching factors. Stretching factor map shows that lower crust flow happened in both of COT and sediment basin regions where upper crust decouples with lower crust due to high temperature. Pressure contrast by sediment loading in basins and erosion in sediment-source regions will lead to lower crust flow away from sediment sink to source. Decoupled and fractured upper crust is stretched further by sediment loading and the following compensation would result in relatively thick lower crust than upper crust. In COT regions with thin sediment coverage, low-viscosity lower crust is easier to thin in extensional environment, also the lower crust tends to flow away induced by magma upwelling. Therefore, continental crust on the margin is not stretching in a constant way but varies with the tectonic setting changes. This work is supported by National Natural Science Foundation of China (Grant No. 41506055, 41476042) and Fundamental Research Funds for the Central Universities China (No.17CX02003A).

  6. 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.

  7. Lunar Reconnaissance Orbiter Camera (LROC) instrument overview

    Science.gov (United States)

    Robinson, M.S.; Brylow, S.M.; Tschimmel, M.; Humm, D.; Lawrence, S.J.; Thomas, P.C.; Denevi, B.W.; Bowman-Cisneros, E.; Zerr, J.; Ravine, M.A.; Caplinger, M.A.; Ghaemi, F.T.; Schaffner, J.A.; Malin, M.C.; Mahanti, P.; Bartels, A.; Anderson, J.; Tran, T.N.; Eliason, E.M.; McEwen, A.S.; Turtle, E.; Jolliff, B.L.; Hiesinger, H.

    2010-01-01

    The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) and Narrow Angle Cameras (NACs) are on the NASA Lunar Reconnaissance Orbiter (LRO). The WAC is a 7-color push-frame camera (100 and 400 m/pixel visible and UV, respectively), while the two NACs are monochrome narrow-angle linescan imagers (0.5 m/pixel). The primary mission of LRO is to obtain measurements of the Moon that will enable future lunar human exploration. The overarching goals of the LROC investigation include landing site identification and certification, mapping of permanently polar shadowed and sunlit regions, meter-scale mapping of polar regions, global multispectral imaging, a global morphology base map, characterization of regolith properties, and determination of current impact hazards.

  8. The Open Gateway: Lunar Exploration in 2050

    Science.gov (United States)

    Lawrence, S.; Neal, C.

    2017-01-01

    The Moon, with its fundamental science questions and abundant, potentially useful re-sources, is the most viable destination for near-term future human and robotic exploration. Given what we have learned since Apollo, the lunar frontier now presents an entirely new paradigm for planetary exploration. The Lunar Exploration Roadmap [1], which was jointly developed by engineers, planetary scientists, commercial entities, and policymakers, is the cohesive strategic plan for using the Moon and its resources to enable the exploration of all other destinations within the Solar system by leveraging incremental, affordable investments in cislunar infrastructure. Here, we summarize the Lunar Exploration Roadmap, and describe the immense benefits that will arise from its successful implementation.

  9. Tests of Gravity Using Lunar Laser Ranging

    Directory of Open Access Journals (Sweden)

    Stephen M. Merkowitz

    2010-11-01

    Full Text Available Lunar laser ranging (LLR has been a workhorse for testing general relativity over the past four decades. The three retroreflector arrays put on the Moon by the Apollo astronauts and the French built arrays on the Soviet Lunokhod rovers continue to be useful targets, and have provided the most stringent tests of the Strong Equivalence Principle and the time variation of Newton’s gravitational constant. The relatively new ranging system at the Apache Point 3.5 meter telescope now routinely makes millimeter level range measurements. Incredibly, it has taken 40 years for ground station technology to advance to the point where characteristics of the lunar retroreflectors are limiting the precision of the range measurements. In this article, we review the gravitational science and technology of lunar laser ranging and discuss prospects for the future.

  10. 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.

  11. Electrostatic Separator for Beneficiation of Lunar Soil

    Science.gov (United States)

    Quinn, Jacqueline; Arens, Ellen; Trigwell, Steve; Captain, James

    2010-01-01

    A charge separator has been constructed for use in a lunar environment that will allow for separation of minerals from lunar soil. In the present experiments, whole lunar dust as received was used. The approach taken here was that beneficiation of ores into an industrial feedstock grade may be more efficient. Refinement or enrichment of specific minerals in the soil before it is chemically processed may be more desirable as it would reduce the size and energy requirements necessary to produce the virgin material, and it may significantly reduce the process complexity. The principle is that minerals of different composition and work function will charge differently when tribocharged against different materials, and hence be separated in an electric field.

  12. Deployable structures for a human lunar base

    Science.gov (United States)

    Gruber, Petra; Häuplik, Sandra; Imhof, Barbara; Özdemir, Kürsad; Waclavicek, Rene; Perino, Maria Antoinetta

    2007-06-01

    The study Lunar exploration architecture—deployable structures for a lunar base was performed within the Alcatel Alenia Space “Lunar Exploration Architecture” study for the European Space Agency. The purpose of the study was to investigate bionic concepts applicable to deployable structures and to interpret the findings for possible implementation concepts. The study aimed at finding innovative solutions for deployment possibilities. Translating folding/unfolding principles from nature, candidate geometries were developed and researched using models, drawings and visualisations. The use of materials, joints between structural elements and construction details were investigated for these conceptual approaches. Reference scenarios were used to identify the technical and environmental conditions, which served as design drivers. Mechanical issues and the investigation of deployment processes narrowed the selection down to six chosen concepts. Their applicability was evaluated at a conceptual stage in relation to the timescale of the mission.

  13. 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

  14. 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.

  15. Enhanced radiosensitivity and radiation-induced apoptosis in glioma CD133-positive cells by knockdown of SirT1 expression

    International Nuclear Information System (INIS)

    Chang, C.-J.; Hsu, C.-C.; Yung, M.-C.; Chen, K.-Y.; Tzao Ching; Wu, W.-F.; Chou, H.-Y.; Lee, Y.-Y.; Lu, K.-H.; Chiou, S.-H.; Ma, H.-I

    2009-01-01

    CD133-expressing glioma cells play a critical role in tumor recovery after treatment and are resistant to radiotherapy. Herein, we demonstrated that glioblastoma-derived CD133-positive cells (GBM-CD133 + ) are capable of self-renewal and express high levels of embryonic stem cell genes and SirT1 compared to GBM-CD133 - cells. To evaluate the role of SirT1 in GBM-CD133 + , we used a lentiviral vector expressing shRNA to knock-down SirT1 expression (sh-SirT1) in GBM-CD133 + . Silencing of SirT1 significantly enhanced the sensitivity of GBM-CD133 + to radiation and increased the level of radiation-mediated apoptosis. Importantly, knock-down of SirT1 increased the effectiveness of radiotherapy in the inhibition of tumor growth in nude mice transplanted with GBM-CD133 + . Kaplan-Meier survival analysis indicated that the mean survival rate of GBM-CD133 + mice treated with radiotherapy was significantly improved by Sh-SirT1 as well. In sum, these results suggest that SirT1 is a potential target for increasing the sensitivity of GBM and glioblastoma-associated cancer stem cells to radiotherapy.

  16. dSir2 in the Adult Fat Body, but Not in Muscles, Regulates Life Span in a Diet-Dependent Manner

    Directory of Open Access Journals (Sweden)

    Kushal Kr. Banerjee

    2012-12-01

    Full Text Available Sir2, an evolutionarily conserved NAD+-dependent deacetylase, has been implicated as a key factor in mediating organismal life span. However, recent contradictory findings have brought into question the role of Sir2 and its orthologs in regulating organismal longevity. In this study, we report that Drosophila Sir2 (dSir2 in the adult fat body regulates longevity in a diet-dependent manner. We used inducible Gal4 drivers to knock down and overexpress dSir2 in a tissue-specific manner. A diet-dependent life span phenotype of dSir2 perturbations (both knockdown and overexpression in the fat body, but not muscles, negates the effects of background genetic mutations. In addition to providing clarity to the field, our study contrasts the ability of dSir2 in two metabolic tissues to affect longevity. We also show that dSir2 knockdown abrogates fat-body dFOXO-dependent life span extension. This report highlights the importance of the interplay between genetic factors and dietary inputs in determining organismal life spans.

  17. 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.

  18. Age and isotope evidence for the evolution of continental crust

    International Nuclear Information System (INIS)

    Moorbath, S.

    1978-01-01

    Irreversible chemical differentiation of the mantle's essentially infinite reservoir for at least the past 3800 Ma has produced new continental, sialic crust during several relatively short (ca. 100-300 Ma) episodes which were widely separated in time and may have been of global extent. During each episode (termed 'accretion-differentiation superevent'), juvenile sial underwent profound igneous, metamorphic and geochemical differentiation, resulting in thick (ca. 25-40 km), stable, compositionally gradational, largely indestructible, continental crust exhibiting close grouping of isotopic ages of rock formation, as well as mantle-type initial Sr and Pb isotopic ratios for all major constituents. Isotopic evidence suggests that within most accretion-differentiation superevents - and especially during the earlier ones - continental growth predominated over reworking of older sialic crust. Reworking of older sialic crust can occur in several types of geological environment and appears to have become more prevalent with the passage of geological time. It is usually clearly distinguishable from continental growth, by application of appropriate age and isotope data. (author)

  19. Crusted scabies in a chid with systemic lupus erythematosus

    Directory of Open Access Journals (Sweden)

    Nurimar C.F. Wanke

    1992-03-01

    Full Text Available A child with systemic lupus erythematosus who has been treated with prednisone for three years, developed crusted scabies. Scrapings from lesions revealed Sarcoptes scabiei adult mites mad eggs. The patient died with septicemia and renal failure soon after starting topical 20% sulfur. A marked improvement was observed in the cutaneous lesions.

  20. Rainfall intensity effects on crusting and mode of seedling ...

    African Journals Online (AJOL)

    Predicted changes in rainfall intensity due to climate change are likely to influence key soil health parameters, especially structural attributes and crop growth. Variations in rainfall intensity will impact crop ... and growth in these soils. Keywords: climate change, crusting, mineralogy, penetration resistance, soil organic matter ...