Romy Rodriguez Martinez: Constraining the interior structure and composition of low-mass, terrestrial planets

Over the past decade, hundreds of small exoplanets with sizes between 1 and 4 Re, so-called super-Earths and mini-Neptunes, have been discovered. Such small planets are the most common in the Galaxy and yet, beyond measurements of their masses and radii, not much is known about their structure, formation, and potential habitability. Mass and radius are often insufficient to reliably constrain the composition of such planets. Thus, the host star’s refractory elemental abundances have recently been used as a proxy for a planet’s interior structure and bulk composition. In this talk, I will present a statistical framework that combines a planet’s bulk physical properties with the abundances of its host star to constrain the composition of low-mass planets. I will then present an application of this framework to K2-106b, an ultra-short period super-Mercury candidate with one of the highest densities observed. I will also discuss the applicability of this framework to planets discovered by TESS and how it will help us prioritize the best targets for future atmospheric characterization.