Biography
I use a stellar simulator for ultraviolet photochemistry on different planetary and exoplanetary surface and cloud environments, in order to explore the diverse astronomical and geochemical contexts for prebiotic chemistry. My expertise is in chemical kinetics, primarily in the context of atmospheric chemistry and astrochemistry.
PhD in Physics from Ohio State University (2012) Advisers: Eric Herbst & Richard Freeman
BS in Physics from University of Colorado Health Sciences (2005)
Research
I'm primarily exploring prebiotic chemistry proceeding from hydrogen cyanide and other feedstock molecules at high concentrations in surface environments. The two scenarios I explore in depth are (a) impact-generated craters where cyanide and other feedstock molecules are stored in organometallic complexes, to be liberated by interaction with water and ultraviolet light, and then activated and transformed by that ultraviolet light; (b) volcanic systems that are ultra-reduced, and can generate cyanide and/or its chemical precursors. I explore these scenarios using a combination of experiment and theory.
Experiment
I am designing a star in the lab: an experimental apparatus to simulate plausible surface environments, by using lamps and filters to supply ultraviolet light that is similar to the young sun, and surfaces and mixtures supplied either by impacts or by magmatic outgassing. This apparatus is called StarLab, and presently resides in the Mott Building.
Theory
I employ atmospheric and magma chemistry models based on a comprehensive chemical network that is valid for H/C/N/O chemistry, incorporating some metallic chemistry as well as limited (but growing) Cl/S/P networks. The models are benchmarked against observations of Earth, Mars, Jupiter, exoplanets (from ultra-hot to warm Jupiters), and, recently, Venus. These models are applied to atmospheres of varying oxidation states, representing the broad uncertainty about Earth's atmosphere during the Hadean (< 3.8 Ga), the time when life likely originated on Earth. They are used to model photochemistry, energetic particle chemistry, and chemistry induced by lightning and impacts. I work closely with colleagues who employ more robust and self-consistent magma chemistry, atmospheric evolution, energetic particle propagation and early impact models in the attempt to obtain a comprehensive view of the global atmospheric and surface environment of the Hadean Earth, and to provide insight about local environments within which the first chemical steps toward life may have occurred.
