Physical Sciences and Mathematics Commons^™

Growth Of Methanogens In The Presence Of Perchlorate Salts: A Study For Possible Life On Mars, John Cale

Biological Sciences Undergraduate Honors Theses

The Phoenix Lander collected soil samples from Mars, and it detected perchlorate salts in its analysis [1]. As oxidizing agents, perchlorates pose a threat to the hypothesis that there may be microbial life on Mars. Since Mars is very dry, perchlorate may continue to accumulate in the soil. If anaerobic methanogens inhabit Mars, then they must be able to grow in the presence of perchlorate salts. There were four species of methanogens tested in this project. The methanogens were first exposed to small concentrations of calcium perchlorate, and then they were gradually tested at higher concentrations. Growth was measured by …

Effects Of Mars Regolith Analogs, Uvc Radiation, Temperature, Pressure, And Ph On The Growth And Survivability Of Methanogenic Archaea And Stable Carbon Isotope Fractionation: Implications For Surface And Subsurface Life On Mars, Navita Sinha

Graduate Theses and Dissertations

Mars is one of the suitable bodies in our solar system that can accommodate extraterrestrial life. The detection of plumes of methane in the Martian atmosphere, geochemical evidence, indication of flow of intermittent liquid water on the Martian surface, and geomorphologies of Mars have bolstered the plausibility of finding extant or evidence of extinct life on its surface and/or subsurface. However, contemporary Mars has been considered as an inhospitable planet for several reasons, such as low atmospheric surface pressure, low surface temperature, and intense DNA damaging radiation. Despite the hostile conditions of Mars, a few strains of methanogenic archaea have …

Experimental Simulations Of Recurring Slope Lineae And Other Flow Formation Features On Mars, Julia Ann Heydenreich

Graduate Theses and Dissertations

Various flow formation features from gullies to recurring slope lineae (RSL) have been identified across the martian surface. The formation of these geologic features are still being determined. Recently, several aspects of these flow features indicate that salt water flows in the subsurface during the warmer months when the ice melts. This paper explores the formation of these processes using laboratory experimental simulations. Experiments were conducted in a wooden flume under varying martian conditions of temperature, slope angle, regolith simulant and a liquid subsurface flow. By adjusting the flume at specific heights, several slopes were obtained to mimic the slopes …

Variability Of Mars' Seasonal North Polar Cap, Richard W. Schmude Jr.

Georgia Journal of Science

Mars’ seasonal north polar cap (hereafter sNPC) underwent year-to-year changes between 2008 and 2015 or Mars years 29–33. The writer monitored changes in the sNPC using images made with the MARCI camera onboard the Mars Reconnaissance Orbiter (MRO). Nine isolated bright spots corresponding to Korolev, Lomonosov, and Louth Craters, the albedo features Ierne, Olympia (or Lemuria), and Cecropia, and three unnamed features were examined. The following was concluded: 1) the sNPC underwent small year-to-year changes between 2008 and 2015 [MY = 29–33], 2) there are no years where all temporary frost features lasted longer than their mean lifespan, and 3) …

Discipline-Based Planetary Education Research And Computational Fluid Dynamics Analysis Of Mars, Filis Coba

Physics Theses & Dissertations

This thesis originates from the testing and implementation of an IRB-approved interactive animation designed to help students understand what causes The Reasons For The Seasons (RFTS) on Earth. Results from the testing indicated a small improvement in student understanding after exposure to the animation. Next, using the 3-D mapping tool Google Earth, students explored seasons and other planetary features on Mercury, Venus, the Moon and Mars through IRB-approved interactive tours which were developed and tested for astronomy education. Results from the tests indicated that there were statistically significant learning gains (p-value < 0.05) after students interacted with the tours compared to those who did not. The development of the tours inspired a geophysics study of the possibility of former plate motion (or plate tectonics) on Mars. A 2-D finite element convection model for the mantle of Mars was designed and solved using COMSOL Multiphysics 5.1, to investigate whether or not thermal gradients in a Mars-sized planet could cause vigorous upper mantle convection, consistent with plate tectonic processes. Results from this project indicated that stable convection could occur in the interior of a Mars-like planet assuming the presence of sufficiently high thermal gradients at about 0.8 times the mantle temperature of Earth. The convective patterns resembled hot upwelling and cool downwelling which may be similar to subduction-like features. Furthermore, increasing the temperature of the hot boundaries resulted in faster, more rigorous convective motions and a hotter average temperature.

The Martian Surface Radiation Environment- A Comparison Of Models And Msl/Rad Measurements, Daniel Matthiä, Bent Ehresmann, Henning Lohf, Jan Köhler, Cary Zeitlin, Jan Appel, John W. Wilson

Mathematics & Statistics Faculty Publications

Context: The Radiation Assessment Detector (RAD) on the Mars Science Laboratory (MSL) has been measuring the radiation environment on the surface of Mars since August 6th 2012. MSL-RAD is the first instrument to provide detailed information about charged and neutral particle spectra and dose rates on the Martian surface, and one of the primary objectives of the RAD investigation is to help improve and validate current radiation transport models.

Aims: Applying different numerical transport models with boundary conditions derived from the MSL-RAD environment the goal of this work was to both provide predictions for the particle spectra and the radiation …