Research
I study exoplanets around low mass stars with a particular interest in characterizing the surfaces and activity cycles of active M dwarfs. Starspots are ubiquitous on stars with convective outer layers and they complicate the background of exoplanet transit observations. My work addresses outstanding questions about the nature, evolution, structure, spectra, and observational signatures of starspots and their contamination in exoplanet transmission.
Following the launch of TESS, I led a ground-based followup campaign using the Las Cumbres Observatory global network to confirm or rule out planet candidates. The first transit I observed was of ultra-short period M dwarf exoplanet LHS 3844b (Vanderspek+ 2019), which became the first published rocky exoplanet found by TESS.
My observations have led or contributed to several other discoveries of M dwarf exoplanets like the nearby Earth-sized planet LP 791-18 d (Peterson+ 2023) and the earlier discovery of planets LP 791-18 b and c (Crossfield+ 2019), the TOI 2096 system (Pozuelos+ 2023), and the sub-Neptunes TOIs 122b and 237b (Waalkes+ 2021). Each of these worlds is a viable candidate for atmospheric characterization with current or near-future observational instruments.
Exoplanet atmospheres are difficult to detect and characterize, and one way to search for them is by looking for atmospheric outflow of hydrogen from sub-Neptune exoplanets that orbit close to active host stars. I looked for evidence of neutral hydrogen outflow from rocky exoplanet GJ 1132b (Berta+ 2013).