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Articles 31 - 60 of 73
Full-Text Articles in The Sun and the Solar System
Engaging The Greater Lafayette Community In A Journey Through The Earth Sciences: Purdue’S Eaps Earth Science Passport Day Event, Dara Laczniak, Bradley Garczynski
Engaging The Greater Lafayette Community In A Journey Through The Earth Sciences: Purdue’S Eaps Earth Science Passport Day Event, Dara Laczniak, Bradley Garczynski
Engagement & Service-Learning Summit
No abstract provided.
The Undeniable Attraction Of Lunar Swirls, Dany Waller
The Undeniable Attraction Of Lunar Swirls, Dany Waller
Posters-at-the-Capitol Presentations
Lunar swirls are complex patterns on the Moon with distinct brightness signatures and magnetic characteristics. Current research has suggested that the formation of lunar swirls relies on local magnetic fields to shield impinging solar wind, based on a shift in electromagnetic wavelength peaks related to solar radiation and space weathering. Our research combined recent models and methods to characterize these anomalies at the surface of the Moon, exploring the effects of field strength and position. We have produced a high resolution map of a famous swirl named Reiner Gamma using magnetic dipole modeling. These maps and models are considered when …
Methanogens, Plausible Extraterrestrial Life Forms On Mars, And Their Tolerance To Increasing Concentrations Of Illite Clay, Chandler Kern
Methanogens, Plausible Extraterrestrial Life Forms On Mars, And Their Tolerance To Increasing Concentrations Of Illite Clay, Chandler Kern
Biological Sciences Undergraduate Honors Theses
Methanogens, some of Earth’s most primitive prokaryotic organisms, are candidates for possible life forms capable of inhabiting Mars. Specifically, four different species (Methanobacterium formicicum, Methanococcus maripaludis, Methanosarcina barkeri, Methanothermobacter wolfeii) were analyzed for their tolerance to the presence of illite clay. Illite is a crystalline mineral that has been identified from regions of Mars’s surface. Results indicated that all four species grew with some success in the illite at different concentrations. This experimentation with methanogens’ abilities to survive and reproduce in the presence of illite allows for a more accurate understanding of the potential capability of microbial …
The Undeniable Attraction Of Lunar Swirls, Cierra Waller, Dhananjay Ravat
The Undeniable Attraction Of Lunar Swirls, Cierra Waller, Dhananjay Ravat
Posters-at-the-Capitol
Lunar swirls are complex patterns on the Moon with distinct brightness signatures and magnetic characteristics. Current research has suggested that the formation of lunar swirls relies on local magnetic fields to shield impinging solar wind, based on a shift in electromagnetic wavelength peaks related to solar radiation and space weathering. Our research combined recent models and methods to characterize these anomalies at the surface of the Moon, exploring the effects of field strength and position. We have produced a high resolution map of a famous swirl named Reiner Gamma using magnetic dipole modeling. These maps and models are considered when …
Msu And Citizen Cate: A High Definition Look At The Sun’S Inner Corona During The 2017 Solar Eclipse Over Hopkinsville, Kentucky., Jessie Anderson, Ethan Caudill
Msu And Citizen Cate: A High Definition Look At The Sun’S Inner Corona During The 2017 Solar Eclipse Over Hopkinsville, Kentucky., Jessie Anderson, Ethan Caudill
Celebration of Student Scholarship Poster Sessions Archive
No abstract provided.
Strategies For Detecting Biological Molecules On Titan, Catherine Neish, Ralph Lorenz, Elizabeth Turtle, Jason Barnes, Melissa Trainer, Bryan Stiles, Randolph Kirk, Charles Hibbitts, Michael Malaska
Strategies For Detecting Biological Molecules On Titan, Catherine Neish, Ralph Lorenz, Elizabeth Turtle, Jason Barnes, Melissa Trainer, Bryan Stiles, Randolph Kirk, Charles Hibbitts, Michael Malaska
Earth Sciences Publications
Saturn’s moon Titan has all the ingredients needed to produce “life as we know it”. When exposed to liquid water, organic molecules analogous to those found on Titan produce a range of biomolecules such as amino acids. Titan thus provides a natural laboratory for studying the products of prebiotic chemistry. In this work, we examine the ideal locales to search for evidence of, or progression towards, life on Titan. We determine that the best sites to identify biological molecules are deposits of impact melt on the floors of large, fresh impact craters, specifically Sinlap, Selk, and Menrva craters. We find …
The Formation Of Fine-Grained Chondrule Rims In Unequilibrated Ordinary Chondrites, John Bigolski
The Formation Of Fine-Grained Chondrule Rims In Unequilibrated Ordinary Chondrites, John Bigolski
Dissertations, Theses, and Capstone Projects
Fine-grained rims are ubiquitous, non-igneous, features that completely or partially envelope the majority of chondrules within the least equilibrated of the unequilibrated ordinary chondrites (UOCs). A detailed examination of such rims in 4 UOC samples less than petrologic type 3.2 was conducted in order to 1) characterize the relative distribution of rims within chondrite samples, 2) inspect differences between fine-grained rims and adjacent matrix material, 3) petrologically analyze the rims and their relationships with chondrule cores, 4) characterize an ungrouped UOC, Northwest Africa 5717, 5) conduct a microanalytical investigation of rim / matrix boundaries to discern relative chronologies of fine-grained …
Oxygen Isotope Composition Of Water In Martian Meteorites, Oleg Vitalivich Maltsev
Oxygen Isotope Composition Of Water In Martian Meteorites, Oleg Vitalivich Maltsev
Earth and Planetary Sciences ETDs
The oxygen isotope composition of water extracted from Martian meteorites appears not to be in isotopic equilibrium with the silicate portion of the meteorites. This disequilibrium suggests the existence of multiple distinct oxygen isotope reservoirs on planet Mars. Here we present oxygen isotope measurements of waters extracted from Martian shergottites Tissint, Zagami and NWA-7042 and from nakhlite NWA-10153. These waters were extracted by stepwise heating to preserve segregation between low temperature adsorbed waters, intermediate temperature mineral waters and the high temperature mineral structural OH groups. The results of our study, analyzed cooperatively with previous work by Karlsson et al., (1992) …
A Quantitative Analysis Of The Fretted Terrain Valleys, Arabia Terra, Mars, Kelsey Anne Mason
A Quantitative Analysis Of The Fretted Terrain Valleys, Arabia Terra, Mars, Kelsey Anne Mason
Open Access Theses & Dissertations
Fretted terrain describes regions on Mars with low-lying, flat valleys separated by steep cliffs that often form polygonal-shaped mesas. The fretted terrain valleys have a morphology distinct from other valleys found on Mars, and their unknown origin may hold insights into critical questions about Mars' tectonic, magmatic, and hydrologic history. Current hypoThesis for the formation of the fretted terrain include fracturing as well as hydrological flow processes such as fluvial or glacial erosion. The region for this study is located in eastern Arabia Terra and is the type-location for fretted terrain. By qualitatively and quantitatively documenting the planform, or map-view, …
Growth Of Methanogens In The Presence Of Perchlorate Salts: A Study For Possible Life On Mars, John Cale
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 …
Investigating Mineral Stability Under Venus Conditions: A Focus On The Venus Radar Anomalies, Erika Kohler
Investigating Mineral Stability Under Venus Conditions: A Focus On The Venus Radar Anomalies, Erika Kohler
Graduate Theses and Dissertations
Radar studies of the surface of Venus have identified regions with high radar reflectivity concentrated in the Venusian highlands: between 2.5 and 4.75 km above a planetary radius of 6051 km, though it varies with latitude. Previous research has proposed several theories on the source of these anomalies, including increased surface roughness, metallic materials with higher dielectric constants, or ferroelectric materials. Prior work suggests several processes that could be the origin of these anomalies, such as surface-atmospheric interactions or low lying clouds or fog. Alternatively, these anomalies could result from a semi-metallic compound trapped at the cooler conditions in the …
Understanding The Surface Induced Phosphorylation Of Prebiotic Molecules By Schreibersite, Danna Qasim
Understanding The Surface Induced Phosphorylation Of Prebiotic Molecules By Schreibersite, Danna Qasim
Master of Science in Chemical Sciences Theses
The study of the surface of a meteoritic mineral, schreibersite (Fe,Ni)3P, was investigated to provide insight into the role of the mineral’s surface in aqueous-phase phosphorylation reactions. The optimization of a custom-designed ultrahigh vacuum (UHV) apparatus and Fe2NiP (schreibersite) surface was performed to permit surface science analysis. The bare surface was characterized by scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS), which showed some oxidation and segregation of phosphorous within the near-surface region. The interaction and/or reaction of water (H2O), methanol (CH3OH), formic acid …
Investigation Of Lunar Subsurface Cavities Using Thermal Inertia And Temperature Maximum To Minimum Ratios, Rachel Ann Slank
Investigation Of Lunar Subsurface Cavities Using Thermal Inertia And Temperature Maximum To Minimum Ratios, Rachel Ann Slank
Open Access Theses & Dissertations
Previous studies have revealed a small number of subsurface cavities, including lava tubes, as well as skylights, lava flow pits, and impact melt pits on the Moon. The interiors of subsurface cavities would have been protected from micrometeorite bombardment, solar radiation, space weathering, and extreme diurnal temperature swings over long periods of geologic time. As a result, subsurface cavities can provide access to pristine crustal samples and stratigraphy. These cavities may also harbor important volatiles, such as water ice, that would enable future exploration missions by relieving many operational constraints, including the supply of propellants and life support. In addition, …
Pre-Mission Input Requirements To Enable Successful Sample Collection By A Remote Field/Eva Team, Barbara A. Cohen, Darlene S. S. Lim, Kelsey E. Young, Anna Brunner, Richard C. Elphic, Audrey Horne, Mary C. Kerrigan, Gordon O. Osinski, John R. Skok, Steven W. Squyres, David Saint-Jacques, Jennifer L. Heldmann
Pre-Mission Input Requirements To Enable Successful Sample Collection By A Remote Field/Eva Team, Barbara A. Cohen, Darlene S. S. Lim, Kelsey E. Young, Anna Brunner, Richard C. Elphic, Audrey Horne, Mary C. Kerrigan, Gordon O. Osinski, John R. Skok, Steven W. Squyres, David Saint-Jacques, Jennifer L. Heldmann
Journal of Human Performance in Extreme Environments
We used a field excursion to the West Clearwater Lake Impact structure as an opportunity to test factors that contribute to the decisions a remote field team (for example, astronauts conducting extravehicular activities (EVA) on planetary surfaces) makes while collecting samples for return to Earth. We found that detailed background on the analytical purpose of the samples, provided to the field team, enables them to identify and collect samples that meet specific analytical objectives. However, such samples are not always identifiable during field reconnaissance activities, and may only be recognized after outcrop characterization and interpretation by crew and/or science team …
Thermodynamic Modeling Of Aqueous Geochemistry Of Chlorine Salts: Application To Stability And Habitability Of Liquid Brines On Mars, Amira Elsenousy
Thermodynamic Modeling Of Aqueous Geochemistry Of Chlorine Salts: Application To Stability And Habitability Of Liquid Brines On Mars, Amira Elsenousy
Graduate Theses and Dissertations
The WCL (Wet Chemistry Lab) instrument on board the Mars’s Phoenix Lander has identified the soluble ionic composition of the soil at the landing site. Two important ions were detected at the landing site; perchlorates (ClO4-) with a concentration of ~ 2.4 wt% and chlorides (Cl-) with a concentration of 0.54 wt%. Between chloride and perchlorate ions three other oxidized ions exist and called chlorine ions: hypochlorite ClO - (ox. state +1), chlorite ClO2- (ox. state +3) and chlorate ClO3- (ox. state +5). These oxidized ions might be existed as intermediate species on the surface of Mars but remained undetected. …
Search For Life, John W. Delano Phd
Search For Life, John W. Delano Phd
Atmospheric and Environmental Science Faculty Scholarship
NASA's Astrobiology program seeks to determine the origin and distribution of life in the Milky Way galaxy using scientific expertise from many disciplines (e.g., astronomy, biochemistry, geochemistry). This presentation, which provides an overview of the progress that has been made in this effort, was delivered on 23 June 2015 at the Green Mountain Academy for Lifelong Learning in Manchester, VT. With NASA's development of the Space Launch System (SLS), vigorous multi-disciplinary scientific research, and additional spacecraft (e.g., TESS) for finding and analyzing planets orbiting other stars, exciting discoveries will continue.
Feldspathic Rocks On Mars: Compositional Constraints From Infrared Spectroscopy And Possible Formation Mechanisms, Deanne Rogers, Hanna Nekvasil
Feldspathic Rocks On Mars: Compositional Constraints From Infrared Spectroscopy And Possible Formation Mechanisms, Deanne Rogers, Hanna Nekvasil
Department of Geosciences Faculty Publications
Rare feldspar-dominated surfaces on Mars were previously reported based on near-infrared (NIR) spectral data and were interpreted to consist of anorthosite or felsic rocks. Using thermal infrared (TIR) data over the feldspar detections with the largest areal extent in Nili Patera and Noachis Terra, we rule out felsic interpretations. Basaltic or anorthositic compositions are consistent with TIR measurements, but the geologic contexts for these regions do not support a plutonic origin. Laboratory NIR spectral measurements demonstrate that large plagioclase crystals (>~840 μm) can be detected in mixtures with as much as 50 vol % mafics, which is higher than …
Experimental Simulations Of Recurring Slope Lineae On The Surface Of Mars, Elizabeth Eddings
Experimental Simulations Of Recurring Slope Lineae On The Surface Of Mars, Elizabeth Eddings
Physics, Astronomy and Geophysics Honors Papers
Recurring Slope Lineae (RSL) are active surface features found on rocky Martian slopes commonly in the southern hemisphere equatorial to mid-latitude regions. These low albedo, dark streaks on Mars demonstrate seasonal characteristics;; they appear and grow darker and longer in warm months and fade to possible disappearance in colder months. One proposed mechanism for the formation and evolution of these features by McEwen et al. (2011) is the melting of subsurface water on Mars. The goal of this study was to test this hypothesis by reconstructing features similar to RSL in the lab that display the same seasonal …
Chemical And Petrographic Survey Of Large, Igneous-Textured Inclusions In Ordinary Chondrites, Katherine Armstrong
Chemical And Petrographic Survey Of Large, Igneous-Textured Inclusions In Ordinary Chondrites, Katherine Armstrong
Dissertations and Theses
Our inventory of material from the early solar system includes large, igneous-textured inclusions in O chondrites, whose origin and relationship to their host meteorite is unclear. These inclusions occur in approximately 4% of O chondrites, and are mineralogically, petrographically, and chemically diverse. Petrographic and chemical data from 29 inclusions from 23 host meteorites were collected with optical light and scanning electron microscopy, allowing for the determination of major phase modal abundance and major element bulk chemistry. No correlation between any inclusion property and host meteorite type were found, but some trends were observed. Nine of the inclusions show strong evidence, …
Hunting Starstuff: Searching For Calcium-Aluminum-Rich Inclusions In Cometary Dust, Christian Engelbrecht
Hunting Starstuff: Searching For Calcium-Aluminum-Rich Inclusions In Cometary Dust, Christian Engelbrecht
STAR Program Research Presentations
NASA’s Stardust mission (1999 - 2006) returned physical samples of the particles ejected by the comet 81P/Wild 2, collected in ultralight and extremely low density aerogel. These samples have been extensively analyzed using X-Ray Fluorescence (XRF), among other techniques, to determine the elemental, chemical and mineralogical composition of Wild 2. Because comets are thought to be formed in the icy outer regions of the solar system, billions of years ago, the Stardust data gives us details of the composition of the ancient solar system and its subsequent evolution. One of the surprises to come out of the data is the …
Ice Caves On Extraterrestrial Bodies: What Are The Prospects For Speleogenesis And Detection?, Penelope J. Boston
Ice Caves On Extraterrestrial Bodies: What Are The Prospects For Speleogenesis And Detection?, Penelope J. Boston
The International Workshop on Ice Caves
Potential mechanisms for creating cavities in icy extraterrestrial bodies have been tentatively explored by several authors. On one hand we have examples of mechanisms that create caves in water ice here on Earth. In addition, there may be unique mechanisms on other Solar System objects that do not occur on Earth but might produce cavities, e.g. sublimation of comets upon perihelion passage. The methods of detecting such cavities depend upon the nature of the icy body in question, the potential for orbital or landed missions to visit those bodies in the future, and remote or landed methods for detecting the …
Mars-Relevant Phosphate Minerals And Implications For Martian Habitability, Christopher Adcock
Mars-Relevant Phosphate Minerals And Implications For Martian Habitability, Christopher Adcock
UNLV Theses, Dissertations, Professional Papers, and Capstones
This dissertation is comprised of three studies focused on martian phosphate availability, with an introductory chapter introducing and linking the three studies. Chapter two is on the subject of merrillite synthesis. Merrillite is an extraterrestrial Ca-phosphate mineral similar to the mineral whitlockite and is found as a dominant primary phosphate mineral in martian meteorites. The chapter includes methods of whitlockite and merrillite synthesis as well as a detailed characterization of the produced minerals and a mechanism by which charge balance can be maintained when merrillite is synthesized through dehydrogenation of whitlockite.
Chapter three presents the results of kinetic and thermodynamic …
The Stardust Interstellar Dust Collector Crater Origins And Hypervelocity Cratering At Oblique Angles In Aluminum Foil, Harison Wiesman
The Stardust Interstellar Dust Collector Crater Origins And Hypervelocity Cratering At Oblique Angles In Aluminum Foil, Harison Wiesman
Undergraduate Theses—Unrestricted
From 1999 to 2006 the NASA Stardust mission collected cometary particles from the Wild 2 comet and interstellar dust from the interstellar medium in two collectors made from aerogel tiles and aluminum foil. By studying their isotopic compositions, these particles can provide us with information about nucleosynthetic processes in stars. Both collector trays are being studied for traces of these particles, though a number of challenges have arisen in doing so. Identifying impact craters in the aluminum foil on the interstellar collector tray has been incredibly difficult. In addition to being only a few micrometers or less in diameter, many …
Survey Of ‘Low-Z’ Particles From The Interplanetary Dust Collection In Search Of Idps, Harison Wiesman
Survey Of ‘Low-Z’ Particles From The Interplanetary Dust Collection In Search Of Idps, Harison Wiesman
Undergraduate Theses—Unrestricted
Micrometeorites are one of the most common types of extraterrestrial material that fall to the Earth, beside meteorites and interplanetary dust particles (IDPs). All of these materials are known to contain presolar grains that, when studied in the laboratory, provide information about the origin of the solar system and help to constrain models of nucleosynthesis in stars. Recent studies of micrometeorites revealed the presence of a group of particles with very high C contents. These ultra-carbonaceous Antarctic micrometeorites (UCAMMs) are fine-grained, fluffy particles dominated by highly disordered carbonaceous matter. The presence of H and N isotopic anomalies, abundant presolar grains, …
Modeling Tidally Driven Coulomb Failure At Strike-Slip Linea On Europa, Marissa Elizabeth Cameron
Modeling Tidally Driven Coulomb Failure At Strike-Slip Linea On Europa, Marissa Elizabeth Cameron
Open Access Theses & Dissertations
The surface of Europa is crosscut by a dense network of fractures and there are many candidate faults for studying past tectonic activity. To better understand the role of tidal stress sources and implications for faulting on Europa, we investigate the relationship between shear and normal stresses at four fault zones: Agenor Linea, Rhadamanthys Linea, Conamara Chaos (Agave/Asterius Linea), and Astypalaea Linea, offering a unique comparison of geological activity of fractures residing in geographically diverse locations of Europa. Assuming tidal diurnal and non-synchronous rotation (NSR) stresses are the primary mechanisms for strike-slip tectonism, here we investigate the mechanics of Coulomb …
Infrared Spectra Analysis Of Thermally Altered Iron Phyllosilicates And The Implications For Mars, William Thomas Bryan
Infrared Spectra Analysis Of Thermally Altered Iron Phyllosilicates And The Implications For Mars, William Thomas Bryan
Graduate Theses and Dissertations
This study looks at two iron-rich phyllosilicates, which may be present on Mars. The minerals, greenalite and hisingerite, are rich in iron-II and iron-III, respectively. Small samples (~0.40 grams) of each mineral were crushed and heated in a Lindberg Tube Oven for approximately twenty-four hours at temperatures selected to mimic lava flows and impact events. Following heating, each sample was placed in a Fourier Transform Infrared (FT-IR) spectrometer to collect the near- and mid-infrared spectra. The spectra allowed for these terrestrial analogs to be analyzed with regards to how their structure breaks down with increasing temperature. The samples' colors were …
Magnesium Isotopic Compositions Of The Moon And Achondrites: Implications For Their Origin And Evolution, Fatemeh Sedaghatpour
Magnesium Isotopic Compositions Of The Moon And Achondrites: Implications For Their Origin And Evolution, Fatemeh Sedaghatpour
Graduate Theses and Dissertations
The main objectives of this thesis are to estimate Mg isotopic compositions of the Moon and achondrites, to understand the behavior of Mg isotopes during magmatic differentiation processes in different planetary bodies, and to evaluate the extent of Mg isotopic heterogeneity in the solar system. In order to achieve these goals, Mg isotopes have been measured for 47 well-characterized lunar samples and 22 differentiated meteorites by MC-ICPMS. The limited Mg isotopic variations among mare and highland regolith, mare breccias, and highland impact-melt rocks reflect negligible Mg isotope fractionation during lunar surface processes (e.g. solar wind, cosmic rays, micrometeorite bombardments, meteorite …
Exploring The Surface Liquid And Lake Regions Of Titan With Laboratory Experimentation And Cassini Spacecraft Data, Felix Casimir Wasiak
Exploring The Surface Liquid And Lake Regions Of Titan With Laboratory Experimentation And Cassini Spacecraft Data, Felix Casimir Wasiak
Graduate Theses and Dissertations
The surface liquids and lake regions of Titan are studied utilizing three unique techniques, the results of which are reported in this dissertation. The development of a facility to simulate the surface conditions of Titan, and to conduct experiments on samples within that facility, brings an understanding of Titan's surface not possible through observation and modeling alone. The properties of this facility are presented, including conceptual methodology, design, implementation, performance, and experimental results. The facility, the main component of which is a simulation chamber, allows for Titan temperatures of 90 - 94 K and a 1.5 bar N2 atmosphere. The …
Penetration Forces For Subsurface Regolith Probes, Ahmed Elshafie
Penetration Forces For Subsurface Regolith Probes, Ahmed Elshafie
Graduate Theses and Dissertations
Investigating planetary bodies using penetrometers can provide detailed information about its history and evolution. An estimation of subsurface density and porosity can be made from the shape of the penetration curve. Using penetrometers mounted on planetary platforms could be challenging due to the uncertainty of the subsurface composition and since the maximum allowed force for penetration is the weight of the lander or rover on the surface. Estimation of penetration forces can provide a reliable constraint on the maximum reachable depth without endangering the whole mission. Therefore, knowledge of the required penetration force to specific depths can be helpful in …
Orbital Periodicities Reflected In Ancient Surfaces Of Our Solar System And The Implications For A Record Of Early Life, Dixie Lee Androes
Orbital Periodicities Reflected In Ancient Surfaces Of Our Solar System And The Implications For A Record Of Early Life, Dixie Lee Androes
Graduate Theses and Dissertations
Uniformitarian processes, governed by invariant physical laws, remain the most reliable source for reconstructing the past. Driving many of the repetitive, predictable processes are the orbital dynamics of the Sun-Planet-Moon systems. Astronomical periodicities range from a few hours (tides) to thousands of years (Milankovitch). These periodicities, combined with geomorphic observations of planetary surfaces, constrain the time-dependent processes and allow for reconstruction of events and conditions favorable for sedimentary accumulations. This research suggests that seasonal sedimentary processes are dominant on Titan and Mars, and have played a significant role in the formation of ancient banded-iron formations (BIF's) on Earth.
Earth, Mars, …