This thesis presents the results of a research program characterizing a soil simulant called Fillite, which is composed of alumino-silicate hollow microspheres harvested from the pulverized fuel ash of coal-fired power plants. Fillite is available in large quantities at a reasonable cost and it is chemically inert. Fillite has been selected by the National Aeronautics and Space Administration (NASA) Glenn Research Center to simulate high-sinkage/high-slip environment in a large test bed such as the ones encountered by the Spirit rover on Mars in 2009 when it became entrapped in a pocket of soft, loose regolith on Mars. The terms high-sinkage and high-slip used here describe the interaction of soils with typical rover wheels. High-sinkage refers to a wheel sinking with little to no applied force while high-slip refers to a spinning wheel with minimal traction. Standard material properties (density, specific gravity, compression index, Young's modulus, and Poisson's ratio) of Fillite were determined from a series of laboratory tests conducted in general accordance with ASTM standards. Tests were also performed to determine some less standard material properties of Fillite such as the small strain shear wave velocity, maximum shear modulus, and several pressure-sinkage parameters for use in pressure-sinkage models. The experiments include an extensive series of triaxial compression tests, bender element tests, and normal and shear bevameter tests. The unit weight of Fillite on Earth ranges between 3.9 and 4.8 kN/m3, which is similar to that of Martian regolith (about 3.7 - 5.6 kN/m3) on Mars and close to the range of the unit weight of lunar regolith (about 1.4 - 2.9 kN/m3) on the Moon. The data presented here support that Fillite has many physical and mechanical properties that are similar to what is known about Martian regolith. These properties are also comparable to lunar regolith. Fillite is quite dilatant; its peak and critical angles of internal friction are smaller than those of most other simulants. Smaller shear strength, coupled with much smaller bulk unit weight as compared to other simulants, results in smaller bearing and shearing resistances allowing for better simulation of the intended high-sinkage, high-slip behavior for rover mobility studies. The results of the normal bevameter tests were used to determine parameters for two models available in the literature - the Bekker model and the New Model of Mobility (N2M) model. These parameters were then used to predict the sinkage of a Spirit rover wheel if the rover were to be used on Fillite. The predicted sinkage of a Spirit rover wheel in Fillite was 84% of the wheel diameter, which was within the observed sinkage of 50 to 90% of the wheel diameter of the Spirit rover on Mars. Shear bevameter tests were also performed on Fillite to assess the shear stresses and shear deformations imparted by wheels under torsional loads. The results compared well to the estimated shear stresses and deformations of Martian soil caused by the wheels of the Spirit rover. When compared to other simulants (e.g. GRC-1), the pressure-sinkage and shear stress-shear deformation behaviors of Fillite confirm that Fillite is more suitable for high-sinkage and high-slip rover studies than other typical simulants derived from natural terrestrial soils and rocks.

"The National Aeronautics and Space Administration (NASA) plans to send a human exploration team to Mars within the next 25 years. In support of this effort Hamilton Standard Space Systems International (HSSSI), current manufacturers of the Space Shuttle spacesuit, began exploring alternative solutions for supporting an astronaut during a Martian surface exploration. A design concept was developed by HSSSI to integrate a minimally equipped Martian spacesuit with a robotic support cart capable of providing life support assistance, communications, and independent navigational functions. To promote NASA's visionary efforts and increase university relations, HSSSI partnered with Worcester Polytechnic Institute (WPI) to develop a proof-of-concept robotic support cart system, FIDOE - Fully Independent Delivery of Expendables. As a proof-of-concept system, the primary goal of this project was to demonstrate the feasibility of current technologies utilized by FIDOE's communication and controls system for future Martian surface explorations. The primary objective of this project was to procure selected commercial-off-the-shelf components and configure these components into a functional robotic support cart. The design constraints for this project, in addition to the constraints imposed by the Martian environment and HSSSI's Martian spacesuit, were a one-year time frame and a $20,000 budget for component procurement. This project was also constrained by the protocols defined by the NASA demonstration test environment. The final design configuration comprised of 37 major commercial off-the-shelf components and three individual software packages that integrated together to provide FIDOE's communications and control capabilities. Power distribution was internally handled through a combination of a main power source and dedicated power supplies. FIDOE also provided a stowage area for handling assisted life support systems and geological equipment. The proof-of-concept FIDOE system proved that the current technologies represented by the selected components are feasible applications for a Mars effort. Specifically, the FIDOE system demonstrated that the chosen technologies can be integrated to perform assisted life support and independent functions. While some technologies represented by the proof-of-concept system may not adequately address the robustness issues pertaining to the Mars effort, e.g., voice recognition and power management, technology trends indicate that these forms of technology will soon become viable solutions to assisting an astronaut on a Martian surface exploration."

Rock glaciers play a significant role in the alpine debris transport system. For practical and engineering considerations, identifying the internal structure and its relationship to surface characteristics is significant in terms of how a rock glacier settles during periods of melting, and the mode of deformation. A better understanding of these factors is important for engineers, engineering geologists and geomorphologists who must make prudent evaluations of rock glaciers as potential sites for human development and uses. It is equally important for evaluating potential stores for water on other planets such as Mars. Ground penetrating radar (GPR) shows that the internal structure of a lobate rock glacier located in the San Juan Mountains of southwest Colorado consists of continuous to semi-continuous horizontal layers of ice-supersaturated sediments and coarse blocky rockslide debris which likely formed through catastrophic episodes of rockfall from the cirque headwall. Folds in the uppermost layers correspond to the surface expression of ridges and furrows, indicating that compressive stresses originating in the steep accumulation zone are transmitted downslope through the rock glacier. The rock glacier is a composite feature that formed by a process involving the development and overlap of discrete flow lobes that have overridden older glacial moraine and protalus rampart materials. The latter materials have been incorporated into the present flow structure of the rock glacier. The discovery of rock glacier-like features on Mars suggests the presence of flowing, or once-flowing ice-rock mixtures. These landforms, which include lobate debris aprons, concentric crater fill and lineated valley fill, hold significant promise as reservoirs of stored water ice that could be used as fuel sources for human exploration of Mars and provide a frozen record of the climatic history of the planet. To this end, the rock glacier in this study was used as a surrogate for similar Martian landforms. Liquid water, found to be abundant in this rock glacier, occurs within a network of interconnected channels that permeate throughout the landform. In terms of water storage within Martian analogs, consideration must include the possibility that some water ice may be stored in relatively pure form within lenses and vein networks that are supplied by seasonal frost accumulation and/or water influx from below.

Continental and submarine hydrothermal systems are commonly found around the world. Similar systems that sustain water or other fluids are also likely to exist in planetary bodies throughout the solar system. Also, terrestrial submarine systems have been suggested as the locations of the first life on Earth and may, therefore, provide indications of where to find life on other planetary bodies. The study of these systems is vital to the understanding of planetary heat transfer, chemical cycling, and biological processes; hence hydrothermal processes play a fundamental role in planetary evolution. In this thesis, three particular types of hydrothermal systems are investigated through the development of mathematical models: (1) terrestrial low-temperature diffuse flows at mid-oceanic ridges (MORs), (2) submarine near-axis convection on Earth, and (3) convection driven by magmatic intrusives on Mars. Model set-ups for all systems include a two-dimensional space with a vertical, hot wall, maintained at constant temperature, located adjacent to a water-saturated porous medium at a lower temperature. By assuming that convection occurs vigorously and within a thin layer next to the hot wall, boundary layer theory is applicable. The models provide steady-state, single-phase estimates of the total heat and mass transfer rates in each scenario over permeability ranges of 10^-14 m² to 10^-10 m² for the submarine systems and 10^-14 m² to 10^-8 m² for the Martian systems. Heat output results derived from the boundary layer model suggest that diffuse flow on MORs contributes 50% or less of heat output to the ridge system, which falls at the low end of observations. For the near-axis model, results found that heat transfer in the hydrothermal boundary layer was greater than the input from steady state generation of the oceanic crust by seafloor spreading. This suggests that the size of the mushy zone evolves with time. Heat output and fluid flux calculations for Martian systems show that fluid outflow adjacent to a single intrusion is too small to generate observed Martian surface features in a reasonable length of time.

Jusqu’à peu, Mars était vue comme une planète à substrat crustal homogène, dominé par des basaltes à olivine. Les missions in situ ont contribué à bouleverser cette vision si simpliste. Le rover Curiosity qui sillonne le cratère d’impact de Gale formé à l’Hespérien (3.5-3.8 Ga) creusé dans des roches noachiennes (> 3.8 Ga), a ainsi découvert, grâce aux analyses LIBS (‘laser induced breakdown spectroscopy’) de l’instrument ChemCam, des roches ignées alcalines felsiques noachiennes, révélant un magmatisme primitif évolué (Sautter et al., 2016) : ce résultat est en accord avec l’identification récente de clastes ignés felsiques d’âge Noachien observés dans la brèche martienne NWA 7533 et ses paires. Une croûte primitive martienne évoluée de type ‘continentale’ aurait-elle existé ? C’est ce que suggère ce travail de par l’observation orbitale GRS de plusieurs terrains noachiens felsiques enrichis en K et Th et abondants en feldspaths. Par ailleurs, du fait de l’identification de feldspaths peu calciques dans les roches et clastes de Gale et de la brèche, il est envisagé ici que la croûte primitive martienne ait pu se former selon un modèle différent de l’océan de magma défini sur la Lune. De plus, la quantification de Li, Rb, Sr et Ba dans l’ensemble des matériaux ignés de Gale analysés par la LIBS ainsi que leurs concentrations dans les clastes ignés de la brèche, suggèrent l’existence de plusieurs réservoirs magmatiques primitifs. En parallèle, la quantification du Cu à partir des données LIBS effectuée dans cette étude, met en évidence des abondances anormalement élevées dans des roches potassiques de la région de Kimberley. Majoritairement associées à des silicates détritiques ignés, ces phases de cuivre proviendraient d’une source magmatique primitive siliceuse localisée dans le flanc Nord de Gale. Au Noachien, la circulation hydrothermale dans un magma évolué aurait formé un gisement métallifère de cuivre aux alentours du cratère. Finalement, la Terre et Mars sont géologiquement plus proches que jamais / Until recently, Mars was considered as a planet with a homogeneous crust dominated by olivine-rich basalts. This simplistic vision has been largely disrupted especially with results of recent in situ missions. In this way, the Curiosity rover that travels in Gale crater, which formed by impact during the Hesperian period (3.5-3.8 Gyr) within igneous basement rocks dated at 4.2 Gyr, discovered Noachian alkaline igneous rocks (> 3.8 Gyr) using the ChemCam LIBS instrument (‘laser induced breakdown spectroscopy’): this observation along with the recent identification of Noachian igneous felsic clasts within the breccia meteorite NWA 7533 and subsequent paired stones, revealed an evolved primitive magmatic system (Sautter et al., 2016). Would an evolved ‘continental’ primitive crust have ever existed on Mars? This is favored in this work by orbital GRS observations showing several Si-K-Th-rich Noachian terrains displaying abundant feldspars. Besides, the identification of low-Ca feldspars within the clasts of the breccia and Gale rocks, suggests that the primitive martian crust may have formed according to a model that differs from the lunar magma ocean. In addition, the LIBS quantification of Li, Rb, Sr and Ba presented in this work in igneous rocks, along with the distribution of alkali trace elements within the igneous clasts of the breccia, suggests the potential occurrence of several magmatic reservoirs. Concurrently, in the Kimberley formation, copper quantification using LIBS data, reveals anomalously elevated abundances within potassic rocks: these Cu-phases mainly associated with detrital igneous silicates, would come from a primitive felsic igneous source located in the northern rim. During the Noachian period, the hydrothermal circulation within an evolved magmatic chamber favored the formation of a Cu-bearing deposit in Gale vicinity. After all, the Earth and Mars are geologically closer than ever

This thesis focuses on the analysis of heavy noble gases (argon, krypton and xenon) and halogens (chlorine, bromine and iodine) in Martian meteorites. In the absence of a sample-return mission, Martian meteorite analysis is essential for establishing evidence for an active fluid system, evaluating the potential for life and understanding the formation and evolution of Mars. Noble gas analysis has multiple applications for Martian meteorite study, as described in this thesis. The noble gas isotopic signatures of Earth’s atmosphere, Martian atmosphere and Martian interior are sufficiently different that they can be distinguished through noble gas analysis. Analysis of bulk and mineral separates of shergottites showed that Martian atmospheric Xe was distributed evenly amongst samples, whilst terrestrially weathered samples contained elevated concentrations of terrestrial atmospheric Xe. Both atmospheric components were introduced by weathering. Shock redistribution is responsible for the distribution of Martian atmosphere into more retentive sites. Crustal contamination may be responsible for the presence or absence of detectable 129Xe from the Martian atmosphere. Halogen abundances can be determined as an extension of the Ar-Ar dating technique. As the halogen system on Earth acts as a tracer for important fluid related processes, Martian halogen abundances in meteorites may provide a tracer for the Martian fluid system. Analysis of bulk and mineral separates of nakhlites showed that halogens are distributed amongst minor phases and clear variation of Br/Cl and I/Cl ratios was observed amongst samples. Elevated I concentrations in low temperature releases of finds NWA 998 and MIL 03346 are consistent with terrestrial contamination. Analysis of Nakhla, (a meteorite fall), showed a trend of elevated Br/Cl and I/Cl ratios in crush and low temperature releases, consistent with Br/Cl ratios observed in Martian rocks, soils and weathering products. In contrast, high temperature releases had lower I/Cl and Br/Cl ratios, which are broadly comparable to the terrestrial mantle. This trend may represent mixing of hydrothermal fluids (low Br/Cl and I/Cl) and surface brines (high Br/Cl and I/Cl). An impact-induced hydrothermal system may provide a mechanism for mixing of both fluid types. The crystallisation ages of nakhlite meteorites were determined using the Ar-Ar dating technique. The apparent ages measured were similar to previous Ar-Ar analysis, and older than reported for other chronometers. Previously unrecognised components were observed, including evidence for a trapped hydrous fluid. This Cl-rich component showed strong correlation with 40Ar and had 40Ar/36Ar and 40Ar/129XeXS ratios consistent with Martian atmosphere. As this component was released during crush and low temperature analysis, fluid inclusions formed by percolation of brines from the Martian surface are likely hosts. Both finds showed clear evidence of a trapped component with 40Ar/36Ar ratios similar to either terrestrial atmosphere or the Martian interior. A further component observed in olivine phases had low 40Ar/36Ar ratios, and likely formed by the release of 36Ar formed by cosmic-ray spallation reactions on iron.

This thesis examines the relationship between Cold War science fiction fix-up novels and social cycle theory. The study engages with textual, cultural, and comparative analysis to elucidate and analyze links between the fix-up novel format, a cyclical conception of human history, and the Cold War setting of the construction and publication of three SF novels. The objects of this study are three Cold War era fix-up novels with origins in World War II pulp science fiction magazine short stories: The Martian Chronicles by Ray Bradbury, City by Clifford D. Simak, and A Canticle for Leibowitz by Walter M. Miller Jr. The project examines these three novels alongside the reflective nature of the fix-up novel format, the authors' interactions with social cycle theory, and the Cold War cultural considerations of ideological instability and the threat of annihilation. By examining these works through the lens of retroactive continuity, social cycle theory, and the Cold War cultural imaginary, this thesis demonstrates the complex interplay between literature, culture, and history, and the ways in which SF authors have used their works to engage with the pressing concerns of their time. / Master of Arts / The Cold War era novels The Martian Chronicles by Ray Bradbury, City by Clifford D. Simak, and A Canticle for Leibowitz by Walter M. Miller Jr. share origins in pulp science fiction magazine short stories. These authors consolidated and revised previously published short stories to produce these works, known as fix-up novels. These three fix-up novels interact with representations of human progress as cyclical or non-linear. This project examines how the Cold War setting of the authors may have influenced science fiction authors' conceptions of human progress as cyclical. This thesis studies how the revision process of creating fix-up novels combined with the transition from World War II to the societal anxieties of the Cold War may have impacted the cultural messages of these novels.

A numerical model for inductive plasma wind tunnels is developed. This model provides the flow conditions at the edge of a boundary layer in front of a thermal protection material placed in the plasma jet stream at the outlet of an inductive torch. The governing equations for the hydrodynamic field are derided from the kinetic theory. The electromagnetic field is deduced from the Maxwell equations. The transport properties of partially ionized and unmagnetized plasma in weak thermal nonequilibrium are derived from the Boltzmann equation. A kinetic data base of transport collision integrals is given for the Martian atmosphere. Multicomponent transport algorithms based upon Krylov subspaces are compared to mixture rules in terms of accuracy and computational cost. The composition and thermodynamic properties in local thermodynamic equilibrium are computed from the semi-classical statistical mechanics. The electromagnetic and hydrodynamic fields of an inductive wind tunnel is presented. A total pressure measurement technique is thoroughly investigated by means of numerical simulations.

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