Exploring Interdisciplinary Space: Interpreting the 40Ar/39Ar Ages of Shocked Ordinary Chondrites, Modeling the Likely Mineralogy of Bulk-Silicate Exoplanets, & Reimagining the Participatory Technology Assessment for NASA Decadal Surveys

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Solar System history has been shaped by impact processes, such as large-body collisions. The history of impact events is constrained by dating shocked meteorites. Constraining the solar system impact history informs models of solar system formation and can provide insight

Solar System history has been shaped by impact processes, such as large-body collisions. The history of impact events is constrained by dating shocked meteorites. Constraining the solar system impact history informs models of solar system formation and can provide insight into solar system processes around other stars. However, there is a long-standing issues using the 40Ar/39Ar chronometer, the most widely used impact event chronometer, to date heavily impacted meteorites. This issue has resulted in artificially old ages in some heavily shocked samples, up to 7 billion years old, which is far older than the age of the Solar System. In Chapters 2 & 3 I examine four heavily shocked meteorites to elucidate the cause of anomalously old impact ages and recommend best practices for future 40Ar/39Ar impact age interpretations.Over 5,000 exoplanets have been identified using astronomical observations, which has supported new exoplanetary science over the last few decades. Exoplanetary science is still in a nascent stage but progressing quickly. Now more than ever, an interdisciplinary approach can be used to build the foundations of exoplanet sciences. Many geoscience inquiries, such as exoplanet compositions, dynamics of exoplanetary mantles and crusts, and the likelihood of habitability, are just beginning to be addressed. In Chapter 4, I use stellar abundance-derived exoplanet mantle compositions to interrogate the variability in exoplanet compositions and the likelihood of primitive crust formation. The results of this work have significant implications for exoplanet mantle dynamics, melting behavior, and the likelihood of plate tectonics. Lastly, over the last few decades, there have been pushes for science and the innovation that results from it to be conducted responsibly and openly. Moreover, the U.S. federal government has undertaken a transformational path to make federal agency-funded science more open and accessible. One method of increasing open science in science-funding agencies is to make the science and mission prioritization decision process more democratic. The NASA Decadal Surveys are an example of community-driven democratic decision-making in the space sciences and set the science and mission goals for the whole space science community. To support a citizen-centered democratic approach, I develop an expanded model of the participatory technology assessment (pTA) process for use in NASA’s Decadal Surveys.