Cosmochemistry Commons^™

Improvements To Isru For Rocket Fuel Generation, Justin Sharp

James Madison Undergraduate Research Journal (JMURJ)

The development of efficient in-situ resource utilization (ISRU) technologies is crucial for the establishment of an extraterrestrial, self-sustaining colony. The generation of rocket fuel at potential colony locations is necessary to provide the transportation of people and cargo to and from these locations.Three processes are discussed for the improvement of ISRU methods to generate rocket fuel: electrolysis and electrochemical improvements to the process of crude fuel production, physical and chemical methods for separation of gaseous H2 and O2, and materials and cryogenics engineering for storage and transportation of liquid hydrogen (LH2) and liquid oxygen (LOX). Storage and transportation of cryogenics …

Petrology And Geochemistry Of Evolved Achondrites: Planetesimal Mantles And Crusts, Zoltan Vaci

Earth and Planetary Sciences ETDs

Melting and differentiation are fundamental to early solar system evolution on planetary bodies that accreted enough material to heat up radioactively or through impacts and breach their solidi. Partially and fully melted material is present in the meteorite record in the form of primitive achondrites and achondrites, which are fragments of planetesimals that underwent heating events in the first few million years of solar system history. Although the vast majority of this material is mafic or ultramafic, new evolved samples, recovered in the last few decades, are pushing the petrologic and geochemical boundaries of planetesimal melting, differentiation, and crust formation. …

An Experimental Study Of Evaporites On Titan: Implications For Lake Composition And Future Missions, Ellen Czaplinski

Graduate Theses and Dissertations

Titan is the only other planetary body in the solar system with liquid on the surface. With a surface temperature and pressure of 89 – 94 K and 1.5 bar (N2), respectively, Titan’s lakes are comprised of liquid hydrocarbons, predominantly methane and ethane. Over time, Titan’s lakes may evaporate, leaving behind residual deposits (evaporites). The evaporation processes and composition of the evaporites is poorly understood. I address these outstanding questions by experimentally investigating the physical and spectral properties of evaporites at Titan surface conditions using an experimental chamber.

Chapter 1 addresses the formation of ethylene evaporites. Ethylene evaporites form more …

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 …

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.

Catalyzed Synthesis Of Zinc Clays By Prebiotic Central Metabolites, Marcelo I. Guzman, Ruixin Zhou, Kaustuv Basu, Hyman Hartman, Christopher J. Matocha, S. Kelly Sears, Hajatollah Vali

Chemistry Faculty Publications

How primordial metabolic networks such as the reverse tricarboxylic acid (rTCA) cycle and clay mineral catalysts coevolved remains a mystery in the puzzle to understand the origin of life. While prebiotic reactions from the rTCA cycle were accomplished via photochemistry on semiconductor minerals, the synthesis of clays was demonstrated at low temperature and ambient pressure catalyzed by oxalate. Herein, the crystallization of clay minerals is catalyzed by succinate, an example of a photoproduced intermediate from central metabolism. The experiments connect the synthesis of sauconite, a model for clay minerals, to prebiotic photochemistry. We report the temperature, pH, and concentration dependence …

Stable Isotope Chemistry In Titan Haze Aerosol, Allison Wold, Thomas Gautier, Jennifer Stern, Joshua Sebree, Melissa Trainer

Research in the Capitol

Titan, a moon of Saturn, has a thick atmosphere made up of nitrogen and a few percent methane, with a surface pressure of 1.5x that of Earth. Titan’s atmosphere is believed to be that similar to that of early Earth before the rise of O2. One significant source of information on the history and evolution of the atmosphere is the measurement of stable isotopes of elements in the molecules of major gases such as nitrogen, methane, and higher order hydrocarbons. The fractionation associated with the formation of Titan aerosol analogs are explored in the laboratory as a function of environmental …

Photocatalytic Reduction Of Fumarate To Succinate On Zns Mineral Surfaces, Ruixin Zhou, Marcelo I. Guzman

Chemistry Faculty Publications

The reductive tricarboxylic acid (rTCA) cycle is an important central biosynthetic pathway that fixes CO₂ into carboxylic acids. Among the five reductive steps in the rTCA cycle, the two-electron reduction of fumarate to succinate proceeds nonenzymatically on the surface of photoexcited sphalerite (ZnS) colloids suspended in water. This model reaction is chosen to systematically study the surface photoprocess occurring on ZnS in the presence of [Na₂S] (1–10 mM) hole scavenger at 15 °C. Experiments at variable pH (5–10) indicate that monodissociated fumaric acid is the primary electron acceptor forming the monoprotic form of succinic acid. The following …