NASA Postdoctoral Program - Developing a physically-motivated picture of stellar activity at rotational timescales for EPRV studies

The NASA Postdoctoral Program (NPP) offers unique research opportunities to highly-talented scientists to engage in ongoing NASA research projects at a NASA Center, NASA Headquarters, or at a NASA-affiliated research institute. These one- to three-year fellowships are competitive and are designed to advance NASA's missions in space science, Earth science, aeronautics, space operations, exploration systems, and astrobiology. This specific research opportunity focuses on using high resolution ground-based spectrographs to discover planets around nearby stars via the Doppler radial velocity (RV) 'wobble' technique. The fellowship will involve working with a team of field-leading exoplanet detection experts to analyze high resolution spectroscopic data from EPRV facilities to isolate and model the effects of granulation, stellar pulsations, and rotationally-modulated signals at the spectral level. The research aims to improve understanding of stellar activity, which can masquerade as planetary signals in stellar RV time series and dwarf the minute planetary Doppler reflex motion induced by Earth-like planets. The successful applicant will leverage a library of high-resolution spectra of active stars spanning a wide range of effective temperatures to derive and test different spectroscopic measurement metrics and techniques aimed at identifying stellar activity signals in radial velocity time series, with the eventual goal of applying these techniques to other spectroscopic data sets of nearby stars to improve detection sensitivity to smaller planets. This activity is crucial as a precursor science goal for the Habitable Worlds Observatory, which will require a well-vetted list of EPRV-detected exo-Earth planets.