Maitrayee Bose Colloquium Abstract (Nov 16, 2016)

Exploring Solar System History through Isotopic Analysis of Extraterrestrial Dust

I study meteorites in order to understand the processes that aided and guided the formation of small planetary bodies and planets in our solar system. One of the main themes of my research is to investigate, through isotopic analyses, raw materials that came together to form the solar system. Presolar grains or stardust that was formed in different kinds of stars, was present in the interstellar space before the solar system formed, some survived solar system formation, and are identified in primitive solar system materials. Each grain carries a signature of the isotopic composition of the stellar ejecta and thus provides a probe of nucleosynthesis within the parent star. Another theme of my research is to characterize organic macromolecules in meteorites for its isotopic compositions and molecular forms. Astrochemical models that are used to study the dynamic evolution of protoplanetary disk can incorporate this information, and improve our understanding of how biocritical elements are processed during the initial stages of planet formation, and how they depend on stellar type and disk properties. Finally, I am interested in studying volatiles, e.g., H, Li, and S, and use them as tracers of conditions and processes in interstellar space and in the early solar system.

I will describe the isotopic compositions of presolar mineral grains and organic materials identified in pristine meteorites using Secondary Ion Mass Spectrometry at the nano-scale (NanoSIMS). I will highlight additional examples of my collaborative research with the NanoSIMS at Arizona State University of meteoritic materials. These studies have profound implications in the Planetary Science field, and will surely benefit the analysis of samples returned by Hayabusa II and OSIRIS-REx.