Cosmochemistry Commons^™

Microstructural Constraints On The Nebular And Asteroidal Histories Of Calcium-Aluminum-Rich Inclusions From Cv3 Chondrites, Shaofan Che

Earth and Planetary Sciences ETDs

The petrology and mineralogy of calcium-aluminum-rich inclusions (CAIs) from CV3 carbonaceous chondrites have been investigated using transmission electron microscopy (TEM). The goal of this dissertation is twofold: (1) to gain new insights into the nebular processes, such as vapor-solid reactions, accretion, transport, that are responsible for the formation of non-igneous CAIs, and (2) to better understand the role of fluid in the secondary alteration of CAIs on the CV3 chondrite parent body. This work represents the first systematic microstructural study of CAIs from CV3 chondrites.

Chapter 2 presents the microstructural observations of primary mineralogies of fine-grained, spinel-rich inclusions (FGIs) from …

Mars 2020: A Step Closer To The Red Planet, Kevin Ng, Matthew Khargie, Omadevi Singh, Sashi Singh, Nazrul I. Khandaker, Rajendra Persaud

Publications and Research

This research paper primarily focuses on the NASA Mars 2020 mission, but will also revisit and discuss past rover missions. As the Mars 2020 mission is ongoing, some information will be updated accordingly. For decades, humans have dreamed of the colonization of Mars for many reasons, such as some similarities shared by Earth and Mars or the close proximity to our planet. In fact, dozens of films, books, and articles have been written, especially in the past 2 decades, about the possibility. As technology advances, we develop newer equipment to hopefully make this possibility into a reality. Of course, placing …

Microgravity And Its Bearing With Space Flight-Related Research, Farhan Tanvir, Nazrul I. Khandaker, Rajendra Persaud, Jeff Guan

Publications and Research

This study investigates the unique properties and applications of microgravity in the context of spaceflight research. Understanding and harnessing the behaviors of a microgravity environment opens up the doors to long-term space travel and consequently, future missions to other planets within our solar system. More specifically, simulating and conducting experiments in microgravity environments helps us explore its effects on the various necessary tasks and behaviors that are carried out during spaceflight. The most immediate and pronounced effects of microgravity are on human physiology. In particular, studies have shown that prolonged exposure to microgravity can result in a 20% decrease in …

Human Health And Wellness In Space: A Review Of Common Effects, Current Research, And Methods Of Prevention, Sonnet Xu, Rajendra Persaud, Nazrul I. Khandaker, Jasmin Budhan

Publications and Research

Space poses a threat to space crew wellness, where microgravity, isolation, radiation, and other conditions exert strain on human health. This study explores the changes to the human body in space and how it contributes to major threats to health during spaceflights. The effects of the hostile environment of outer space are all examined here, along with resultant changes to behavior, physiology, and the difficulty of remote diagnosis for health treatment in space. This review also considers the implications to the human cartilage, brain, and eyes along with the various other hazards and physiological alterations.

Human health in space is …

Effects Of Terrestrial Weathering On Rare Earth Element Concentrations And Sulfur Isotopic Signatures Of Carbonaceous And Ordinary Chondrites, Ruby Virginia Patterson

Graduate Theses and Dissertations

Understanding the effects of weathering of chondrites is essential to gaining accurate and useful information about the formation of our solar system, as well as a more detailed account of the mobilization of chondritic compounds when they encounter terrestrial conditions. Elemental concentrations and stable isotope analyses of chondrites, considered to be the most primordial material in the solar system, are two tools which help unlock the weathering patterns of these specimens when they enter the earth system. However, it is not currently known exactly how time spent in the field alters rare earth element (REE) concentration or δ34S signatures within …

An Experimental Investigation Of Liquid Hydrocarbons In A Simulated Titan Environment, Kendra Farnsworth

Graduate Theses and Dissertations

Saturn’s moon, Titan, has surface conditions (89–94 K, 1.5-bar atmosphere) that permit lakes of methane, ethane, and dissolved atmospheric nitrogen. The effects of atmospheric nitrogen on methane-ethane liquid properties is poorly understood, leading to uncertainty in Titan modeling. I address this question by experimentally investigating the physical properties of methane-ethane liquids under a 1.5-bar nitrogen atmosphere in a simulated Titan environmental chamber.

Chapter 1 addresses nitrogen dissolution kinetics in Titan’s liquid hydrocarbons. I found an exponential increase in nitrogen quantity and diffusion coefficients with increasing methane mol%. I find that Titan’s liquids are likely not saturated in nitrogen, with dissolution …

Early Meteoritic Records Of Asteroidal Melt And Impact Environments, Brendt Hyde

Electronic Thesis and Dissertation Repository

The characterization of meteorites formed in early melt and impact environments helps deepen our understanding of the processes involved in the formation and modification of terrestrial bodies in the solar system. The main objective of this thesis is to interpret and describe a range of igneous and metamorphic environments on asteroidal bodies, through the chemical, microstructural and isotopic analysis of meteorites, and to place these in the context of evolving rocky bodies in the early protoplanetary disk. Study of the meteorite Northwest Africa (NWA) 869 has led to the novel discovery of a eucrite impactor clast in chondritic regolith material. …

Measured Optical Absorption Cross Sections Of Tio, Peter Bernath

Chemistry & Biochemistry Faculty Publications

A laboratory emission spectrum of TiO in the visible and near-infrared regions (476–1176 nm) has been calibrated and corrected. High-resolution experimental absorption cross sections for TiO with natural isotopic abundance are provided at a temperature of about 2300 K. These cross sections have been compared with those derived from the ExoMol line list. The experimental cross sections can be used directly as a template for cross correlation TiO detection in hot Jupiter exoplanets.