Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 155 for “"Martian"”.
-
The role of C-O-H volatiles in the martian mantle and the production of the martian atmosphere.
… suggests that liquid water was once eroding the martian surface at rates comparable to many climates on present-day Earth. However, the thin modern martian atmosphere does not support liquid water. The fundamental variable in the evolution of the martian atmosphere is the storage of C-O-H …
-
Impact Melt-Bearing Deposits Around Martian Craters
… we investigate impact melt emplacement around Martian craters. We compare our results to melt emplacement processes found on Venus, the Moon, and Mercury. We tentatively find Martian melt emplacement more closely resembles Venusian emplacement, rather than lunar emplacement. This suggests …
-
Vertically Propagating Tides in the Martian Atmosphere
… of tides on the mean state of the present-day Martian atmosphere is especially large at high altitudes. Certain tides can propagate away from the region of generation in the lower atmosphere and reach the upper atmosphere, where they can achieve significant amplitudes. Such vertically …
-
Non-migrating tides in the Martian thermosphere
Previous studies have identified longitudinal structures associated with non-migrating tides in observations of the upper neutral atmosphere of Mars. MAVEN’s Imaging Ultraviolet Spectrometer (IUVS) observations of the upper atmosphere reveal variations in density with longitude at altitudes of 130 …
-
Natural and artificial orbits around the Martian moon Phobos
… human missions to Mars is the exploration of the Martian moons. In particular, Phobos is becoming an appealing destination for future scientific missions of NASA and ESA. Phobos is a tiny celestial body that orbits around Mars at low altitude. The unique combination of these two characteristics …
-
A motion vision system for a Martian Micro-Rover
This thesis describes a monocular, motion vision system that was designed to meet the size, power, and processing constraints of a small, robotic, planetary explorer. The computational requirements of the brightness gradient approach, which is commonly used in motion vision systems, were found to …
-
Radiative Transfer in the Martian Environment: In-Situ Results from the MSL Curiosity Rover and Laboratory Experimentation on Martian Regolith and Crystalline Rock Analogs
… Gale Crater. Radiative transfer modeling of the martian atmosphere benefits from this quantification of low-lying dust. This dissertation aims to expand our knowledge of the radiation environment of Mars into its surface and subsurface. The scattering of radiation through analog martian materials …
-
Lithospheric dynamics of Earth’s subduction zones and Martian tectonic provinces
… dynamics of Earth’s subduction zones and Martian tectonic provinces on multiple time scales. In Chapter 2, I use geodetic observations to constrain the post-seismic viscoelastic deformation following the 1960 M9.5 Valdivia, Chile earthquake and quantify its stressing onto the 2010 M8.8 …
-
Effect of Chemistry on Electrodynamics in the Martian Dynamo Region
… approach focuses on numerical studies using the Martian Multifluid Magnetohy drodynamic (MF-MHD) Model (M4). The dynamo is a region which varies in time and space due to the lack of a global planetary intrinsic magnetic field, the location of the remnant crustal fields, and the planetary rotation …
-
Temporal and Geographical Variation in Martian Surface Dust Lifting Processes
… examining the variability of key aspects of the Martian dust cycle and investigating their importance in predicting conditions for spacecraft atmospheric descent and landing. The dust cycle – lifting, transportation and deposition – is a significant Martian climate cycle. The geographical and …
-
Growth and Survivability of Microorganisms at Martian Temperatures and Pressures
<p>The discovery of methane in the martian atmosphere via numerous ground- and space-based sources has prompted the study of methanogens as models for life on Mars. Methanogens are microorganisms within the domain Archaea, many of which utilize carbon dioxide (CO2) and hydrogen to produce methane. …
-
Investigations of the Martian Mid-Latitudes: Implications for Ground Ice
This dissertation examines several questions in Martian surface processes relating to water or ice using a combination of geomorphology and modeling. I first examine sublimation of ice from new small mid-latitude craters with freshly exposed ice imaged by the High Resolution Imaging Science …
-
Lithospheric dynamics of Earth's subduction zones and Martian tectonic provinces
… dynamics of Earth's subduction zones and Martian tectonic provinces on multiple time scales ranging from short-term earthquake deformation to long-term tectonic loading. In Chapter 2, I use geodetic observations to constrain the postseismic viscoelastic deformation following the 1960 M9.5 …
-
The composition of the Martian dark regions : observations and analysis
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Sciences, 1980.
-
Study of the Martian upper atmosphere using radio tracking data
Since the first in situ observations of the Martian atmosphere were made by the twin Viking landers, we have learned considerably more about its composition, dynamics and variability. Not only did the new data on global atmospheric densities generate opportunities to understand the atmospheric …
-
A zonally and annually averaged study of potential early Martian atmospheres
Observations of the surface of Mars suggest a high probability of surface water activity in that planet's past. Consequently, many studies of Mars' early atmosphere have attempted to estimate the carbon dioxide level by requiring that surface temperatures be high enough to support surface liquid …
-
Automatic Classification and Segmentation of Patterned Martian Ground Using Deep Learning Techniques
… by prioritizing downlink of meaningful data. Martian polygonally cracked ground is actively studied by planetary geologists and may be indicative of subsurface water. Filtering images containing these polygonal features can be used as a case study for science autonomy and to reduce the …
Page 1 of 8