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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Low-Shield Volcanism: A Comparison of Volcanoes on Syria Planum, Mars and Snake River Plain, Idaho

Henderson, Amanda Olivia 01 November 2015 (has links)
Volcanoes are key indicators of a planet's internal structure, mechanics, and evolutionary history. Consequently, understanding the types and ages of volcanoes on a planet's surface is an important endeavor. In an attempt to better understand the relationship between morphometry and volcanic processes, we compared low-shield volcanoes on Syria Planum, Mars, with basaltic shields of the eastern Snake River Plain. We used 133 volcanoes on Syria Planum that are covered by Mars Orbiting Laser Altimeter (MOLA) and High Resolution Stereo Camera (HRSC) elevation data and 246 eSRP shields covered by the National Elevation Dataset (NED) for this comparison. Shields on Syria Planum average 191 +/- 88 m tall, 12 +/- 6 km in diameter, 16 +/- 28 km3 in volume, and have 1.7° +/- 0.8 flank slopes. eSRP shields average 83 +/- 44 m tall, 4 +/- 3 km in diameter, 0.8 +/- 2 km3 in volume, and have 2.5° +/- 1 flank slopes. Bivariate plots of morphometric characteristics show that Syria Planum and Snake River Plain low shields form the extremes of the same morphospace shared with some Icelandic olivine tholeiite shields, but are generally distinct from other terrestrial volcanoes. Cluster analysis of Syria Planum and Snake River Plain shields with other terrestrial volcanoes separates these volcanoes into one cluster and the majority of them into the same sub-cluster that is distinct from other terrestrial volcanoes. Principal component and cluster analysis of Syria Planum and Snake River Plain shields using height, area, volume, slope, and eccentricity shows that Syria Planum and Snake River Plain low-shields are similar in shape (slope and eccentricity). Apparently, these low shields formed by similar processes involving Hawaiian-type eruptions of low viscosity (mafic) lavas with fissure controlled eruptions, narrowing to central vents. Initially high eruption rates and long, tube-fed lava flows shifted to the development of small lava lakes that repeatedly overflowed, and on some with late fountaining to form steeper spatter ramparts. However, Syria Planum shields are systematically larger than those on the eastern Snake River Plain. The larger size of Syria Planum shields is likely due to the smaller gravity of Mars, requiring larger magma batches to generate sufficient buoyant force to overcome the strength of rocks in the lithosphere and rise to the surface. Thus, Syria Planum lavas erupt in larger volumes and at higher rates generating larger volcanoes with slightly smaller slopes.
32

A mesoscale model study of atmospheric circulations for the northern hemisphere summer on Mars

Tyler, Daniel Jr 01 October 2004 (has links)
The Penn-State/NCAR MM5 mesoscale model was adapted for mesoscale simulations of the Martian atmosphere (the OSU MMM5). The NASA Ames Mars GCM provides initial and boundary conditions. High-resolution maps for albedo, thermal inertia and topography were developed from Mars Global Surveyor (MGS) data; these baseline maps are processed to appropriate resolutions for use in the GCM and the mesoscale model. The OSU MMM5 is validated in Chapter 2 by comparing with surface meteorology observed at the Viking Lander 1 (VL1) and Mars Pathfinder (MPF) landing sites. How the diurnal cycle of surface pressure (the surface pressure tide) is affected by boundaries, domain/nest choices and the resolution of surface properties (topography, albedo and thermal inertia) is examined. Chapter 2 additionally shows the influence of regional slope flows in the diurnal surface pressure cycle for certain locations on Mars. Building on the methods of Chapter 2, Chapter 3 describes the northern midsummer polar circulation and the circulations (both large and small scale) that influence it. Improvements to the model for these studies include: the topographical gradient is now considered when computing surface insolation, and the thermal inertia maps and model initialization are improved for high latitudes; this yields a realistic simulation of surface temperatures for the North Pole Residual Cap (NPRC) and the surrounding region. The midsummer polar circulation is vigorous, with abundant and dynamically important transient eddies. The preferred locations of transients varies significantly during this study, between L[subscript s]=l20 and L[subscript s]=l50. At L[subscript s]=l20 transient circulations are seen primarily along the NPRC margin, consistently producing strong flow over the residual cap (~l5 m/s). By L[subscript s]=135, transient eddies form a "storm track" between the northern slopes of Tharsis and the NPRC. By L[subscript s]=150, the circulation is becoming strong and winter-like. These transient eddies may be important in the Martian annual water cycle; many of the observed circulations are poorly (or not) simulated in present day Mars GCMs. Increased resolution and polar stereographic domains provide improvement over GCMs for high latitude studies of atmospheric circulations. These results are in agreement with recent observations. Future work includes model refinements and water vapor transport studies. / Graduation date: 2005
33

Entwicklung, Implementierung und Erprobung eines planetaren Informationssystems auf Basis von ArcGIS / Development, implementation and validation of a planetray informationsystem based on ArcGIS

Saiger, Peter Paul January 2007 (has links)
Mit der Entwicklung der modernen Raumfahrt Mitte der 60er-Jahre des zwanzigsten Jahrhunderts und der Eroberung des Weltraums brach eine neue Epoche der bis dato auf Beobachtungen mit dem Teleskop gestützten planetaren Forschung an. Während des Wettrennens um die technologische Führerschaft im All zur Zeit des Kalten Krieges war das erste Ziel die Entsendung von Satelliten zur Erdbeobachtung, denen aber schon bald Sonden zum Mond und den benachbarten Planeten folgten. Diese Missionen lieferten eine enorme Fülle von Informationen in Form von Bildern und Messergebnissen in unterschiedlichen Datenformaten. Diese galt und gilt es zu strukturieren, zu verwalten, zu aktualisieren und zu interpretieren. Für die Interpretation terrestrischer Daten werden geographische Informationssysteme (GIS) hinzugezogen, die jedoch für planetare Anwendungen aufgrund unterschiedlicher Voraussetzungen nicht ohne weiteres eingesetzt werden können. Daher wurde im Rahmen dieser Arbeit die für die Verwaltung von geographischen Daten der Erdfernerkundung kommerziell erhältliche Software ArcGIS Desktop 9.0 / 9.1 (ESRI) mit eigenen Programmen und Modulen für die Planetenforschung angepasst. Diese ermöglichen die Aufbereitung und den Import planetarer Bild- und Textinformation in die kommerzielle Software. Zusätzlich wurde eine planetare Datenbank zur Speicherung und zentralen Verwaltung der Informationen aufgebaut. Die im Rahmen dieser Arbeit entwickelten Softwarekomponenten ermöglichen die schnelle und benutzerfreundliche Aufbereitung der in der Datenbank gehaltenen Informationen und das Auslesen in Dateiformate, die für geographische Informationssysteme geeignet sind. Des Weiteren wurde eine „Werkzeugleiste“ für ArcGIS entwickelt, die das Arbeiten mit planetaren Datensätzen beträchtlich beschleunigt und vereinfacht. Sie beinhaltet auch Module zur wissenschaftlichen Interpretation der planetaren Informationen, wie beispielsweise der Berechnung der Oberflächenrauigkeit der Marsoberfläche inklusive der flächendeckenden Kalibrierung der Eingangs-Basisdaten. Exemplarisch konnte gezeigt werden, dass das Verfahren eine verbesserte Berechnung der Oberflächenrauigkeit ermöglicht, als bisher angewandte Ansätze. Zudem wurde eine auf ArcGIS basierende Prozesskette zur Berechnung von hierarchischen Flussnetzen entwickelt und erprobt. Das terrestrische Beispiel, die Analyse eines Abflusssystems auf Island, zeigte eine sehr große Übereinstimmung der errechneten Gewässernetze mit den morphologischen Gegebenheiten vor Ort. Daraus ließ sich eine hohe Genauigkeit der mit demselben Ansatz errechneten Gewässernetze auf dem Mars ableiten. Auf der Grundlage der in dieser Arbeit entwickelten Programme und Module lassen sich auch Daten zukünftiger Missionen aufbereiten und in ein solches System einbinden, um diese mit eigenen Ansätzen zu verwalten, zu aktualisieren und für neue wissenschaftliche Fragestellungen perfekt anzupassen, einzusetzen und zu präsentieren, um so neue wissenschaftliche Erkenntnisse in der Planetenforschung zu gewinnen. / After previously only telescopic observations, a new era of planetary research started in the middle of the 60s with the emergence of modern spaceflights and the conquest of the outer space. During the Cold War, there was a period of conflict and competition between the United States and the Soviet Union for technological leadership in the outer space, the aim being to lift satellites into space for observing the Earth. Later, satellites followed for the exploration of the moon and our neighboring planets. These missions generated a huge amount of technical results and images having diverse data formats. This information needs to be structured, administrated, updated and interpreted. The geographic information system (GIS) is a tool for management and analysis of terrestrial data but has limits for planetary applications. Therefore we implemented modules and computer programs into the commercially available software ArcGIS Desktop 9.0 / 9.1 (ESRI), used for the administration of spatial information in terrestrial remote sensing, providing tools for planetary research. These supplements allow the processing and import of planetary text and visual information into this commercial software. Furthermore a planetary database was established allowing storage and central administration of information. The software developed during this thesis enables the user fast and easy processing of data stored in the database and readout in data formats applicable for geographic information systems. Moreover a toolbar was developed for ArcGIS that enhances and simplifies dealing with planetary datasets. This toolbar contains modules for the scientific interpretation of planetary information as for example tools for the calculation of the surface roughness of the planet mars including area-wide calibration of the basic data. As an example, it is shown in this thesis that this procedure allows a more accurate calculation of the surface roughness than approaches used so far. Furthermore a workflow based on ArcGIS was generated and tested for the calculation of hierarchical drainage networks. A terrestrial example based on a dataset from Iceland shows a high concordance between the computer-generated drainage network and the real morphological situation. This tool allows the calculation of drainage networks with high accuracy on Mars. The programs and modules developed in this thesis provide the basis for processing and structuring datasets generated in future space missions. This planetary information and analysis system allows administration, updating, and adaptation to scientific questions and the presentation of data leading thereby to new insights in the planetary research.
34

A temperature profile comparison between GM3 and the Mars Global Surveyor Radio Occulation dataset /

Rosso, Adam M. January 2007 (has links)
Thesis (M.Sc.)--York University, 2007. Graduate Programme in Earth and Space Science. / Typescript. Includes bibliographical references (leaves 119-121). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR38822
35

NUMERICAL MODELING OF THE DIURNAL WINDS NEAR THE MARTIAN POLAR CAPS

Burk, Stephen Dwight, 1945- January 1975 (has links)
No description available.
36

Aqueous alteration of olivine in nakhlite Miller Range (MIL) 03346

Stopar, Julie D January 2007 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2008. / Includes bibliographical references (leaves 208-234). / xiv, 234 leaves, bound ill. (some col.) 29 cm
37

Thermal analysis and thermal control system requirements for a solar sail Mars mission /

Tiedemann, Maik, January 1991 (has links)
Report (M. Eng.)--Virginia Polytechnic Institute and State University, 1991. / Vita. Abstract. Includes bibliographical references (leaves 75-76). Also available via the Internet.
38

Spectroscopy of jarosite minerals, and implications for the mineralogy of Mars/

Rothstein, Yarrow. January 2006 (has links) (PDF)
Undergraduate honors paper--Mount Holyoke College, 2006. Dept. of Astronomy. / Includes bibliographical references (leaves 80-87).
39

Imaginative geographies of Mars the science and significance of the red planet, 1877-1910 /

Lane, Kristina Maria Doyle, January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.
40

Potential mineral resources on Mars: Ore processes and mechanisms

Crandall, Jake 01 May 2015 (has links)
Ore-forming processes are relatively well understood on Earth, but little is known about mineralization processes on Mars. By applying terrestrial analogs, using data collected from orbital and rover missions and evidence for hydrothermal activity from alteration assemblages, the types and locations of different ore-forming processes have been investigated with the aim of discovering concentrations of mineral resources on Mars. These resources are likely to be of critical importance for future manned missions to Mars, and insight gained towards mineralization on Mars may also advance our understanding of terrestrial deposits.

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