abstract: Impact craters are ubiquitous throughout the Solar System, formed by one of the principal processes responsible for surface modification of terrestrial planets and solid bodies (i.e., asteroids, icy moons). The impact cratering process is well studied, particularly on the Moon and Mercury, where the results remain uncomplicated by atmospheric effects, plate tectonics, or interactions with water and ices. Crater measurements, used to determine relative and absolute ages for geologic units by relating the cumulative crater frequency per unit area to radiometrically-determined ages from returned samples, are sensitive to the solar incidence angle of images used for counts. Earlier work is quantitatively improved by investigating this important effect and showing that absolute model ages are most accurately determined using images with incidence angles between 65&deg; and 80&deg;, and equilibrium crater diameter estimates are most accurate at ~80&deg; incidence angle. A statistical method is developed using crater size-frequencies to distinguish lunar mare age units in the absence of spectral differences. Applied to the Moon, the resulting areal crater densities confidently identify expansive units with >300&ndash;500 my age differences, distinguish non-obvious secondaries, and determine that an area >1&times;104 km2 provides statistically robust crater measurements. This areal crater density method is also applied to the spectrally-homogeneous volcanic northern smooth plains (NSP) on Mercury. Although crater counts and observations of embayed craters indicate that the NSP experienced at least two resurfacing episodes, no observable age units are observed using areal crater density measurements, so smooth plains emplacement occurred over a relatively short timescale (<500 my). For the first time, the distribution of impact melt on Mercury and the Moon are compared at high resolution. Mercurian craters with diameters &ge;30 km have a greater areal extent of interior melt deposits than similarly sized lunar craters, a result consistent with melt-generation model predictions. The effects of shaking on compositional sorting within a granular regolith are experimentally tested, demonstrating the possibility of mechanical segregation of particles in the lunar regolith. These results provide at least one explanation toward understanding the inconsistencies between lunar remote sensing datasets and are important for future spacecraft sample return missions. / Dissertation/Thesis / Ph.D. Geological Sciences 2013

Cette thèse présente Lion, un système de navigation utilisant des informations visuelles et inertielles pour l’atterrissage planétaire de précision. Lion est conçu pour voler au-dessus de n’importe quel type de terrain, plat ou accidenté, et ne fait pas d’hypothèse sur sa topographie. Faire un atterrir un véhicule d’exploration planétaire autonome à moins de 100 mètres d’un objectif cartographié est un défi pour la navigation. Les approches basées vision tentent d’apparrier des détails 2D détectés dans une image avec des amers 3D cartographiés pour atteindre la précision requise. Lion utilise de façon serrée des mesures venant d’un nouvel algorithme d’appariement imagecarteafin de mettre à jour l’état d’un filtre de Kalman étendu intégrant des données inertielles. Le traitement d’image utilise les prédictions d’état et de covariance du filtre dans le but de déterminer les régions et échelles d’extraction dans l’image où trouver des amers non-ambigus. Le traitement local par amer de l’échelle image permet d’améliorer de façon significative la répétabilité de leur détection entre l’image de descente et l’image orbitale de référence. Nous avons également conçu un banc d’essai matériel appelé Visilab pour évaluer Lion dans des conditions représentatives d’une mission lunaire. L’observabilité des performances de navigation absolue dans Visilab est évaluée à l’aide d’un nouveau modèle d’erreur. Les performances du systèmes sont évaluées aux altitudes clés de la descente, en terme de précision de navigation et robustesse au changement de capteurs ou d’illumination, inclinaison de la caméra de descente, et sur différents types de relief. Lion converge jusqu’à une erreur de 4 mètres de moyenne et 47 mètres de dispersion 3 RMS à 3 kilomètres d’altitude à l’échelle. / This thesis introduces Lion, a vision-aided inertial navigation system for pinpoint planetary landing. Lion can fly over any type of terrain, whatever its topography, flat or not. Landing an autonomous spacecraft within 100 meters of a mapped target is a navigation challenge in planetary exploration. Vision-based approaches attemptto pair 2D features detected in camera images with 3D mapped landmarks to reach the required precision. Lion tightly uses measurements from a novel image-tomapmatcher in order to update the state of an extended Kalman filter propagated with inertial data. The image processing uses the state and covariance predictionsfrom the filter to determine the regions and extraction scales in which to search for non-ambiguous landmarks in the image. The individual image scale managementprocess per landmark greatly improves the repeatability rate between the map and descent images. We also designed a lunar-representative optical test bench called Visilab to test Lion on. The observability of absolute navigation performances in Visilab is evaluated with a novel error budget model. Finally, the system performances areevaluated at the key altitudes of a lunar landing, in terms of accuracy and robustness to sensor or illumination changes, off-nadir camera angle, and non-planar topography. We demonstrate error convergence down to a mean of 4 meters and a 3-RMS dispersion of 47 meters at 3 kilometers of altitude in hardware conditions at scale.

The composition is scored for the following instruments: 2 flutes, 2 oboes, 2 clarinets, 2 bassoons and a large percussion section requiring 7 performers. Beneath the Dancing Moon is a programmatic piece in one movement form composed of 5 continuous sections. It depicts a night scene when the elves begin to dance beneath the moon. Later, the moaning ghosts from the dark forest and the witches with brooms come to join them. They dance furiously until the moon disappears, the sea stops dead and all the dancers suddenly vanish. The approximate performance time is 17 minutes.

In the present work, the abnormal glow discharge at atmospheric pressure was generated in the nitrogen-methane (1 to 5 %) gaseous mixtures related to the atmosphere of Titan. The discharge itself was monitored by optical emission spectrometry that confirmed presence of active nitrogen species and various radicals formed from methane. Besides them, the CN spectral bands were observed. Intensities of all light emitting species were studied in the dependence on applied power and composition of nitrogen-methane mixture. The rotational temperature of about 2000 K was calculated from the second positive nitrogen system. The vibrational temperature also obtained from neutral nitrogen molecule increased nearly directly with methane from 3000 K (1 % CH4) to 3600 K (5 % CH4). In the contrary, vibrational temperature obtained from nitrogen molecular ion decreased with methane in the gaseous mixture and increased with applied discharge power from 3700 K to 4200 K. The same trend showed the vibrational temperature calculated from violet system of CN with value from 4600 K to 5800 K. The stable discharge products were analysed by proton transfer time of flight mass spectrometry of the exhausting gas. Presence of many aliphatic and some aromatic hydrocarbons was confirmed as well as quite a lot of amino and cyano compounds. Increasing concentrations of methane have produced more substances with higher molecular weight and less simple substances that were likely to be consumed on more complex substances. Their relative intensities were determined under the same conditions as optical emission spectra were collected.

With the growth of human interest in the Lunar region, methods of enabling Lunar access including surface and Low Lunar Orbit (LLO) from periodic orbit in the Lunar region is becoming more important. The current investigation explores the Lunar access capabilities of these periodic orbits. Impact trajectories originating from the 9:2 Lunar Synodic Resonant (LSR) Near Rectilinear Halo Orbit (NRHO) are determined through explicit propagation and mapping of initial conditions formed by applying small maneuvers at locations across the orbit. These trajectories yielding desirable Lunar impact final conditions are then used to converge impacting transfers from the NRHO to Shackleton crater near the Lunar south pole. The stability of periodic orbits in the Lunar region is analyzed through application of a stability index and time constant. The Lunar access capabilities of the Lunar region periodic orbits found to be sufficiently unstable are then analyzed through impact and periapse maps. Using the impact data, candidate periodic orbits are incorporated in the the NRHO to Shackleton crater mission design to control mission geometry. Finally, the periapse map data is used to determine periodic orbits with desirable apse conditions that are then used to design NRHO to LLO transfer trajectories.

Planetary science is often limited to only surface observations of planets requiring the development of modeling techniques to infer information about the planet’s interior. This work outlines three separate scientific problems that arose from planetary surface observations, the methodology utilized to explain the formation of these observation, and what we learned about the planet’s interior by solving these problems. Chapter 1 discusses why lunar mascon basins (impact basins associated with a central freeair gravity positive) form for only a limited range of basin diameters. Modeling the full formation of South-Pole Aitken (SPA) basin using a sequential two-code (hydrocode and Finite Element Model) shows that due to SPA’s great size (long wavelength) and the high geothermal gradient of the Moon at impact, the basin’s relaxation process was controlled by isostatic adjustment with minimal influence from lithospheric rigidity or membrane stresses. Additionally, the modeling shows that the Moon was hot and weak at impact. Chapter 2 addresses why there is a lack of olivine abundance on Mars around large impact basins, and the formation of the megabreccia that is associated with an orthopyroxene signature in the circum-Isidis Planitia region. Hydrocode modeling of the excavation of the Isidis forming impact shows the impact was more than capable of excavating mantle material and reproducing the observed megabreccia. This coupled with the lack of olivine signature indicates that the Martian upper mantle is orthopyroxene-rich. Chapter 3 covers the investigation into why the nitrogen ice sheet on Pluto, Sputnik Planitia, is the youngest observed terrain and why the surface is divided into irregular polygons about 20– 30 kilometers in diameter. The utilization of a new parameterized convection model enables the computation of the Rayleigh number of the nitrogen ice and shows that the nitrogen ice is vigorously convecting, making Rayleigh–Bénard convection the most likely explanation for these polygons (Trowbridge et al., 2016). Additionally, the diameter of Sputnik Planitia’s polygons and the dimensions of its ‘floating mountains’ of water ice suggest that its nitrogen ice is about five to ten kilometers thick (Trowbridge et al., 2016). The estimated convection velocity of 1.5 centimeters a year indicates a surface age of only around a million years (Trowbridge et al., 2016). The accumulation of this work is three chapters that use three separate techniques to further understand three separate planets.

After the end of World War II, so-called New Religious Movements (NRM) emerged as branches of the traditional religions. These NRM’s are characterized by new ways of forming belief systems and has traditions that are different from the conventional religions. The main purpose of this study was to investigate and study how the Korean founder Sun Myung Moon of the NRM, Family Federation of World Peace and Unification, depict and portray the two genders in his proclamations about human salvation. In addition, the study applied a gender theoretical framework, in order to interpret Moon’s depiction of how gender is described in relation to his doctrine of salvation. What emerge along the course of study was that the path to salvation, depicted in reverent Moon’s enunciations, was the faith in Jesus and the relationship between the man and woman. The study also illustrated that the elimination of evil, such as Satan and the ideology of communism, is the foundation to establish the Kingdom of Heaven on Earth. In conclusion, the salvation of mankind is fulfilled through reverent Moon, as the second Messiah, through the marriage and the reproduction of sinless children. In summary, reverent Moon’s proclamations in his theology, often advocate and encourage the traditional gender roles. Moreover, the theoretical framework visualizes that Moon, in his theology, is depicting a dichotomy and hierarchy among the genders and thereby embraces a conservative view of gender roles. The didactic relevance of this study is the importance to illustrate gender perspective and gender roles within the teaching of religion. That is because it may counteract stereotypical perceptions among students.

The purpose of the investigation was to map the geology of the north end of Craters of the Moon National Monument and surrounding area. A stratigraphic sequence of Late Paleozoic sedimentary and Tertiary volcanic rocks was compiles and the structures of these rocks and contact relationships with intrusions were delineated. Grade and facies of contact metamorphism were defined. The Snake River Plain basalts were also mapped. The sources of these flows were determined where possible. Preexisting structures and relationships of vents to earlier faulting were explored in ascertaining extensions of the Great Rift Zone into the Pioneer Mountains. Petrographic descriptions of the rock units were completed. Study of the economic geology was not undertaken. The interested reader is referred to Nelson (1969) for descriptions of the mineral deposits in the Lava Creek Mining District.

Houses in literature are an important signifier, and for Canadian author L.M. Montgomery, places and especially houses were deeply meaningful. This study explores the portrayal of houses and homes in a selection of L.M. Montgomery’s novels: Anne of Green Gables (1908), Anne of Avonlea (1909), Anne of the Island (1915), Anne’s House of Dreams (1917), Emily of New Moon (1923), The Blue Castle (1926), Emily Climbs (1927), Emily’s Quest (1928), A Tangled Web (1931), Pat of Silver Bush (1933), Mistress Pat (1935), Anne of Windy Willows (1936), and Jane of Lantern Hill (1937). Montgomery’s own attachment to houses and places is evident from The Selected Journals of L.M. Montgomery, Volumes 1-5 (1985-2004), Mary Rubio’s biography, Lucy Maud Montgomery: The Gift of Wings (2008) and Montgomery’s letters, My Dear Mr. M: Letters to G.B. MacMillan from L.M. Montgomery (1980). This study argues that, given Montgomery’s emphasis on the physical environment of her own life, the environment which surrounds the characters of her novels is equally important for deciphering meanings conveyed in her books. Therefore, the study attempts to ascertain what houses in Montgomery’s fiction communicate, drawing on theories of place attachment and emotional relationships with places to explain the significance of the houses in these novels and Montgomery’s depiction of them and their relation to the characters. Research on place attachment and the meaning of home helps to clarify the significance of houses in these novels. Prior analysis of Montgomery’s novels is also taken into account, as well as studies on the house in other fiction. The study shows that the houses in Montgomery’s fiction often function as a symbol for the self. They also facilitate or prevent actions or events which involve the characters, and fulfil the needs of the characters, whether these needs be physical or emotional. I use these functions as an interpretive lens through which I attempt to illuminate aspects of Montgomery’s depiction of houses in these novels as dream houses, haunted houses, houses of nostalgia or escape. Montgomery uses houses to situate the characters in her novels, both physically and emotionally. Close analysis of the passages relating to houses in these novels reveals the depth of detail, the imagery and symbolism, and Montgomery’s careful selection of words and phrases. / Dissertation (MA (English))--University of Pretoria, 2017. / English / MA (English) / Unrestricted

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20602号 / 理博第4317号 / 新制||理||1620(附属図書館) / 京都大学大学院理学研究科地球惑星科学専攻 / (主査)教授 山路 敦, 教授 山 明, 准教授 伊藤 正一 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM