Geoscience and a Lunar Base: A Comprehensive Plan for Lunar Exploration

This document represents the proceedings of the Workshop on Geoscience from a Lunar Base. It describes a comprehensive plan for the geologic exploration of the Moon. The document begins by explaining the scientific importance of studying the Moon and outlines the many unsolved problems in lunar science. Subsequent chapters detail different, complementary approaches to geologic studies: global surveys, including orbiting spacecraft such as Lunar Observer and installation of a global geophysical network; reconnaissance sample return mission, by either automated rovers or landers, or by piloted forays; detailed field studies, which involve astronauts and teleoperated robotic field geologists. The document then develops a flexible scenario for exploration and sketches the technological developments needed to carry out the exploration scenario

Local integrands for the five-point amplitude in planar N=4 SYM up to five loops

Integrands for colour ordered scattering amplitudes in planar N=4 SYM are dual to those of correlation functions of the energy-momentum multiplet of the theory. The construction can relate amplitudes with different numbers of legs. By graph theory methods the integrand of the four-point function of energy-momentum multiplets has been constructed up to six loops in previous work. In this article we extend this analysis to seven loops and use it to construct the full integrand of the five-point amplitude up to five loops, and in the parity even sector to six loops. All results, both parity even and parity odd, are obtained in a concise local form in dual momentum space and can be displayed efficiently through graphs. We have verified agreement with other local formulae both in terms of supertwistors and scalar momentum integrals as well as BCJ forms where those exist in the literature, i.e. up to three loops. Finally we note that the four-point correlation function can be extracted directly from the four-point amplitude and so this uncovers a direct link from four- to five-point amplitudes.Comment: 29 pages LaTeX, 8 figure

Lithologies contributing to the clast population in Apollo 17 LKFM basaltic impact melts

LKFM basaltic impact melts are abundant among Apollo lunar samples, especially those from Apollo 15, 16, and 17. They are generally basaltic in composition, but are found exclusively as impact melts. They seem to be related to basins and so could represent the composition of the lower lunar crust. They contain lithic clasts that cannot be mixed in any proportion to produce the composition of the melt matrix; components rich in transition elements (Ti, Cr, Sc) and REE are not considered. To search for the mysterious cryptic component, we previously investigated the mineral clast population in two Apollo 14 LKFM basaltic impact melts, 15445 and 15455. The cryptic component was not present in the mineral clast assemblage of these breccias either, but some olivine and pyroxene grains appeared to be from lithologies not represented among identified igneous rocks from the lunar highlands. In addition, none of the mineral clasts could be unambiguously assigned to a ferroan anorthosite source. We have now extended this study to Apollo 17, starting with two LKFM impact melt breccias (76295 and 76315) from the Apollo 17 station 6 boulder. The results from the study are presented

Experimental measurement of focused wave group and solitary wave overtopping

Prediction of individual wave overtopping events is important in assessing danger to life and property, but data are sparse and hydrodynamic understanding is lacking. Laboratory-scale waves of three distinct types were generated at the Coastal Research Facility to model extreme waves overtopping a trapezoidal embankment. These comprised wave groups of compact form, wave groups embedded in a background wave field, and a solitary wave. The inshore wave propagation was measured and the time variation of overtopping rate estimated. The total volume overtopped was measured directly. The experiments provide well-defined data without uncertainty due to the effect of reflection on the incident wave train. The dependence of overtopping on a range of wave shapes is thus determined and the influence of wave-wave interactions on overtopping assessed. It was found that extreme overtopping may arise from focused waves with deep troughs rather than large crests. Furthermore, overtopping waves can be generated from small wave packets without affecting the applicability of results to cases in which there are surrounding waves. Finally, overtopping from a solitary wave is comparable with overtopping from focused wave groups of the same amplitude. © 2011 Copyright International Association for Hydro-Environment Engineering and Research

Gauge Invariant Effective Stress-Energy Tensors for Gravitational Waves

It is shown that if a generalized definition of gauge invariance is used, gauge invariant effective stress-energy tensors for gravitational waves and other gravitational perturbations can be defined in a much larger variety of circumstances than has previously been possible. In particular it is no longer necessary to average the stress-energy tensor over a region of spacetime which is larger in scale than the wavelengths of the waves and it is no longer necessary to restrict attention to high frequency gravitational waves.Comment: 11 pages, RevTe

Texas Citrus Mature Orchard Production Costs and Returns--Years 8 to 10+.

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Distributions of the perceptual switches associated with viewing ambiguous stimuli

The ambiguous Necker cube stimulus appears to switch between two alternative perspectives, 'cube-up' and 'cube-down', such that the inter-switch interval gives percept duration. Percept frequency, plotted as a function of duration, is modelled by a gamma distribution, and the model fit is improved by discarding arbitrarily durations greater than three standard deviations above the mean (Borsellino et al, 1972 Kybernetik 10 139 - 144). Alternatively, good fits can be achieved by discarding the 'dead period' at the beginning of the distribution that represents the observer's decision time between a switch and the subsequent response with a key press that signals the switch (Martin, 1967 Papers in Psychology 1 2). Twenty-nine naïve observers recorded switches between cube-up and cube-down percepts. During a total observation period of 10 min, observers recorded up to 300 switches. We found that the best fits were generated with the gamma distribution when the 'dead period' was discarded. Arbitrary trimming of the tail, three standard deviations above the mean, had little impact on goodness-of-fit. This suggests that (i) the perceptual changes can be adequately modelled as a simple stochastic process, and (ii) the modelling is improved by accounting for the decision time between switch and response

Texas Citrus Mature Orchard Production Costs and Returns--Years 8 to 10+.

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Texas Citrus Orchard Establishment Costs.

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