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ASP2019: Earth to Space

John Michael Brewer

Assistant Professor
San Francisco State University

John M. Brewer dove into exoplanet research as a graduate student at SFSU in 2008, working to improve our determinations of the chemical abundances of planet hosting stars. Achieving both improved precision and compositions of a wide array of elements, he was able to leverage that information to better understand the planet formation process for his PhD thesis at Yale. Those insights include that compact systems of rocky planets make up an increasing number of planetary systems at lower metallicities, that carbon-to-oxygen ratios are low in local stars leading to mostly magnesium silicate geology in small planets and that hot Jupiters may migrate via disk-free migration. During his time at Yale, he also designed new observing software for both the CHIRON (at CTIO in Chile) and EXPRES (Lowell Observatory DCT in Arizona) spectrographs and is currently the Deputy Scientist for the 100 Earths project in addition to a new assistant professor at SFSU. With the students in his new research group, Brewer is continuing his work on exploring planet formation and migration as well as searching for Earth sized planets around nearby stars that we may eventually target in the search for life on other worlds.