Chemical Profiles of Dwarf Stars and Their Planets

A revolution in what scientists can measure about planets orbiting other stars (exoplanets) is underway: the elements present in their atmospheres can now be determined. Some of the material that forms a star settles into a disk, and as that material goes on to form planets, the physics and chemistry of that process depends on the relative abundance of each element. Life itself depends on certain elements in excess of typical stellar values, so the topic of extrasolar biosignatures depends on understanding the stellar elemental inventory. Measurements of the elemental abundances in the host stars are needed to interpret what we detect in exoplanet atmospheres. This project will make stellar and planetary abundances available to maximize the scientific payoff from the flood of ultra-precise exoplanetary measurements. The project will support a graduate student in the role of Planetarium Coordinator to bring astronomy education and outreach to under-served communities in the Kansas region. It will also expand an astronomy-themed crafting series called CubeWorlds, an interactive approach to STEM education. The project team pursue these goals using large, public spectroscopic data sets of thousands of planet-hosting stars of interest. The primary focus is the highest-priority targets of FGKM spectral types using data from the world’s foremost observatories. The project team aims to: (a) build a public, data-driven tool to efficiently and precisely derive stellar abundances from spectra, (b) measure elemental abundances for the target lists of leading observatories, and (c) produce a suite of exoplanetary atmosphere models that account for each system’s peculiar stellar abundance patterns. The results will guide future studies of these systems and support the interpretation of upcoming spectroscopy of these systems. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.