Astrophysicist | Exoplaneteer
I study transiting exoplanets and their host stars, with a focus on disentangling stellar and planetary signals in transmission spectra. My work aims to unlock the potential of current and future observatories—like HST, JWST, and Pandora—for robust atmospheric characterization of small exoplanets.
I am a Research Scientist at MIT, working with Prof. Julien de Wit in the Disruptive Planets group. I earned my PhD in Astronomy & Astrophysics at the University of Arizona, where I focused on the impact of stellar photospheric heterogeneity on the interpretation of exoplanet transmission spectra. In a former life, I studied neuroscience at Westminster University and worked as a field biologist in Utah and Arizona.
My work centers on finding and characterizing transiting exoplanets. I'm primarily interested in small exoplanets around nearby small stars that afford the best opportunities for detailed atmospheric studies, including searches for biosignatures in the near future. Stellar photospheric heterogeneity presents the main bottleneck for the characterization of small exoplanets in transmission, and so I work a lot on new approaches for constraining stellar photospheric heterogeneity and disentangling stellar and planetary signals in transmission spectra.
I am the PI of Legacy Archival Programs on the Hubble Space Telescope (HST AR 17551) and the James Webb Space Telescope (JWST AR 5370), which are uniformly analyzing >100 transit observations to infer the photospheric heterogeneity of the host stars and provide exoplanetary transmission spectra that account for possible stellar contamination signals present.
I work with some great teams to find small planets transiting small stars, including SPECULOOS, Project EDEN, and TESS. Most recently, I've had the pleasure of contributing significantly to the discoveries of SPECULOOS-3b, an Earth-sized planet transiting an M6.5 dwarf at 16.8 pc, and TOI-6002b and TOI-5713b, two super-Earths near the radius valley that transit mid-M dwarfs. Transiting M-dwarf systems like these provide our best opportunities to charaterize rocky exoplanets in the next two decades before the launch of the Habitable Worlds Observatory.
Stars and faculae can mimic or mask planetary spectral features in exoplanet transmission spectra. During my PhD, I examined the typical scale of this "transit light source" effect and found this is a concern for essentially all M-dwarf systems and many active G- or K-dwarf systems.
I'm now primarly interested in new approaches to constraining the properties of exoplanet host stars and mitigating this effect. I recently co-led Study Analysis Group 21 of NASA's ExoPAG, which focused on the impact of the TLS effect on precise, space-based transmission spectra. Over the course of 18 months, this interdisciplinary group of >100 scientists identified 14 needs that can be addressed in the coming years to better constrain host-star photospheres and make the most of precise transmission spectra. These feed into seven overarching science questions, which are summarized below and detailed in full in our final report, published as an invited review in RASTI.
Keeping in mind stellar impacts, I'm ultimately interested in studying exoplanet atmospheres, particularly in transmission, which affords us the greatest opportunity today to study small, temperate worlds. To this effect, I use HST and JWST, and I am a founding member of Project ACCESS, which is conducting a large, ground-based transmission spectroscopy survey with the 6.5-m Magellan Telescopes. To date, we've published optical transmission spectra of nine targets, including the sub-Neptune GJ1214 and the ultrahot Jupiters WASP-19b and WASP-103b. In all three of these studies, we infer the presence of unocculted photospheric heterogeneities (i.e., spots and faculae) that alter the observed transit depths, underscoring the importance of constraining stellar photospheres in order to enable unbiased studies of the planetary atmospheres.
