“Spectroscopic eclipse mapping provides detailed information on spatial changes, in both temperature and chemistry, in a planet’s atmosphere. It’s a way to get at fundamental exoplanet parameters, like whether there is a magnetic field and, if so, how strong.”

megan weiner mansfield, ph.d.

As exoplanets slip behind their stars and reemerge, Megan Weiner Mansfield, Ph.D., makes sense of the spectra fanning out at the edges of these secondary eclipses, combining novel approaches with premier observational tools to yield fresh insights on planet formation and habitability.

Her expertise spans geophysics and planetary science, observational astronomy and theory, enabling lateral thinking that leads to discovery.

How the concept of eclipse mapping works for exoplanet WASP-18b. Credit: NASA/JPL-Caltech (R. Hurt/IPAC)

Inspired by exoplanet temperature mapping, Dr. Weiner Mansfield pioneered a method for distinguishing spectral lines of atmospheres across three dimensions. Part of the JWST Early Release Science team, she crafted the first spectroscopic eclipse map of the dayside of an ultra-Hot Jupiter, WASP-18b.

As principal investigator of the ground-based Gemini South Telescope program, she uses the IGRINS instrument—the Immersion Grating INfrared Spectrometer, an instrument that obtains both broad spectral coverage and high spectral resolution—to characterize exoplanet atmosphere composition and dynamics with new precision.

During her fellowship, Dr. Weiner Mansfield will extend these strides in more directions. She will use JWST observations to map more exoplanet daysides in 3D—and study the atmospheric composition of rocky Earth-like exoplanets, seeking life-relevant molecules like water, carbon dioxide, and methane. She will also combine data from JWST and IGRINS to survey carbon and oxygen abundances in giant planet atmospheres, cataloging comparative clues to planetary formation.

In sharpening theory and models with these findings, Dr. Weiner Mansfield will also further the development of observational tools for the future Extremely Large Telescopes, which promise new breakthroughs in planetary knowledge.

Dr. Weiner Mansfield received a Ph.D. in geophysical sciences from the University of Chicago in Summer 2021. Prior to starting her 51 Pegasi b Fellowship, Dr. Weiner Mansfield will continue her work as a NASA Hubble Fellowship Sagan fellow at University of Arizona.