Sciences and Exploration Directorate

Sarah Rose Peacock


Sarah Rose Peacock's Contact Card & Information.
Phone: 301.286.1111
Org Code: 667
Mail Code 667
Greenbelt, MD 20771

Brief Bio

I am interested in the habitability of terrestrial exoplanets as well as other star-planet interactions, primarily relating to the high energy radiation environment to which these planets are exposed. My research is focused on the upper atmospheres and ultraviolet emission from stars. I use the PHOENIX atmosphere code to compute synthetic stellar spectra for exoplanet host stars that span extreme ultraviolet to infrared wavelengths. 

Link to Personal Website

Current Projects

Consortium on Habitability and Atmospheres of M-dwarf Planets (CHAMPS)

Task Lead for Star-Planet Interactions for the NASA ICAR programs: "The M-dwarf Opportunity: Characterizing Nearby M-Dwarf Habitable Zone Planets" and "Strange New Worlds: Characterizing Nearby M-Dwarf Habitable Zone Planets"

Tell Me How I'm Supposed to Breathe With No Air - JWST Transmission Spectra of Rocky Worlds

We are conducting a Large Cycle 1 GO Program to survey 5 rocky exoplanets around the "cosmic shoreline" to search for evidence of atmospheres. So far, two transmission spectra are featureless, consistent with cosmic shoreline predictions of no substantial atmosphere, and two others deviate from a flat line, consistent with either H2O-rich atmospheres or starspots.

PEGASUS: PHOENIX EUV Grid and Stellar UV Spectra

PEGASUS is a generalized grid of 1,225 synthetic spectra for M and K type stars computed with the PHOENIX stellar atmosphere code. The spectra cover wavelengths ranging from 100 A - 100 microns with resolutions of delta lambda <0.01 A across EUV - NUV wavelengths. It is accessed via a webtool ( that retrieves a synthetic spectrum of a specific exoplanet host star, using archival GALEX UV measurements to identify the most representative model.

Star-Planet Activity Research CubeSat (SPARCS)

Science Team Member for the NASA-funded mission, SPARCS


Ph.D., Planetary Sciences, University of Arizona, 2019

Minor: Astrobiology

Dissertation: Predicting the Extreme Ultraviolet Radiation Environment of Exoplanets Around Low-Mass Stars

M.Sc., Planetary Sciences, University of Arizona, 2016

B.A., Astronomy-Physics, University of Virginia, 2013


ASD Peer Award, 2023

Gerard P. Kuiper Memorial Award, 2020

NASA Earth and Space Science Fellowship, 2015 – 2018

UA College of Science Galileo Circle Scholarship, 2016


Exposing the Lyman-alpha Profiles of Low-Mass Stars (Program-16646) - HST Cycle 29 - Awarded: 2021-08-12

Leveraging High Radial Velocities to Get to the Core of Planetary Lyman alpha Transits (Program-16731) - HST Cycle 29 - Awarded: 2021-08-12

Tell Me How I’m Supposed to Breathe With No Air: Measuring the Prevalence and Diversity of M-Dwarf Planet Atmospheres (Program-0198) - JWST Cycle 1 - Awarded: 2021-03-30

Observing the Lyman-alpha Transits of Two Sub-Neptunes Orbiting a 400 Myr G Star to Illuminate the Cause of the Exoplanet Radius Valley (Program-16455) - HST Cycle 28 - Awarded: 2020-11-09

Special Experience

American Astronomical Society

Congressional Visit Day Participant, 2019

The National Academies of Sciences, Engineering, and Medicine

Lloyd V. Berkner Space Policy Intern, Space Studies Board, 2016

Selected Publications


2024. "JWST/NIRCam Transmission Spectroscopy of the Nearby Sub-Earth GJ 341b." The Astronomical Journal 167 (3): 90 [10.3847/1538-3881/ad19df] [Journal Article/Letter]

2024. "Atmospheric Escape From Three Terrestrial Planets in the L 98-59 System." The Astrophysical Journal 961 (1): 115 [10.3847/1538-4357/ad0e0e] [Journal Article/Letter]

2023. "Double Trouble: Two Transits of the Super-Earth GJ 1132 b Observed with JWST NIRSpec G395H." The Astrophysical Journal Letters 959 (1): L9 [10.3847/2041-8213/ad054f] [Journal Article/Letter]

2023. "A JWST transmission spectrum of the nearby Earth-sized exoplanet LHS 475 b." Nature Astronomy 7 (11): 1317-1328 [10.1038/s41550-023-02064-z] [Journal Article/Letter]

2023. "Modeling the Chromosphere and Transition Region of Planet-hosting Star GJ 436." The Astrophysical Journal 954 (1): 73 [10.3847/1538-4357/ace103] [Journal Article/Letter]

2023. "HAZMAT. IX. An Analysis of the UV and X-Ray Evolution of Low-mass Stars in the Era of Gaia." The Astrophysical Journal 951 (1): 44 [10.3847/1538-4357/acd2dc] [Journal Article/Letter]

2023. "High Tide or Riptide on the Cosmic Shoreline? A Water-rich Atmosphere or Stellar Contamination for the Warm Super-Earth GJ 486b from JWST Observations." The Astrophysical Journal Letters 948 (1): L11 [10.3847/2041-8213/accb9c] [Journal Article/Letter]

2023. "The effect of stellar contamination on low-resolution transmission spectroscopy: needs identified by NASA’s Exoplanet Exploration Program Study Analysis Group 21." RAS Techniques and Instruments 2 (1): 148-206 [10.1093/rasti/rzad009] [Journal Article/Letter]

2022. "Accurate Modeling of Lyman-alpha Profiles and their Impact on Photolysis of Terrestrial Planet Atmospheres." The Astrophysical Journal [10.3847/1538-4357/ac77f2] [Journal Article/Letter]

2021. "Time-Resolved Photometry of the High-Energy Radiation of M Dwarfs with the Star-Planet Activity Research CubeSat (SPARCS)." Astronomische Nachrichten [10.1002/asna.20210068] [Journal Article/Letter]

2021. "A New Look into K-giants' Chromospheres." Research Notes of the American Astronomical Society 5 (4): 73 [10.3847/2515-5172/abf4e4] [Journal Article/Letter]

2021. "HAZMAT. VII. The Evolution of Ultraviolet Emission with Age and Rotation for Early M Dwarf Stars." The Astrophysical Journal 907 (2): 91 [10.3847/1538-4357/abd0f0] [Journal Article/Letter]

2020. "SPARCS payload assembly, integration, and test update." Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series 11444 114440A [10.1117/12.2562582] [Proceedings]

2020. "Estimating the Ultraviolet Emission of M Dwarfs with Exoplanets from Ca II and Hensuremathalpha." The Astronomical Journal 160 (6): 269 [10.3847/1538-3881/abbf5c] [Journal Article/Letter]

2020. "HAZMAT VI: The Evolution of Extreme Ultraviolet Radiation Emitted from Early M Stars." The Astrophysical Journal 895 (1): 5 [10.3847/1538-4357/ab893a] [Journal Article/Letter]

2020. "Current Population Statistics Do Not Favor Photoevaporation over Core-powered Mass Loss as the Dominant Cause of the Exoplanet Radius Gap." The Astrophysical Journal 890 (1): 23 [10.3847/1538-4357/ab6605] [Journal Article/Letter]

2019. "Predicting the Extreme Ultraviolet Radiation Environment of Exoplanets around Low-mass Stars: GJ 832, GJ 176, and GJ 436." The Astrophysical Journal 886 (2): 77 [10.3847/1538-4357/ab4f6f] [Journal Article/Letter]

2019. "Predicting the Extreme Ultraviolet Radiation Environment of Exoplanets around Low-mass Stars: The TRAPPIST-1 System." The Astrophysical Journal 871 (2): 235 [10.3847/1538-4357/aaf891] [Journal Article/Letter]

2018. "HAZMAT. IV. Flares and Superflares on Young M Stars in the Far Ultraviolet." The Astrophysical Journal 867 (1): 70 [10.3847/1538-4357/aae2ae] [Journal Article/Letter]

2017. "Stellar and Planetary Parameters for K2textquoterights Late-type Dwarf Systems from C1 to C5." The Astrophysical Journal 837 (1): 72 [10.3847/1538-4357/aa56c7] [Journal Article/Letter]

2017. "A New Model of Roche Lobe Overflow for Short-period Gaseous Planets and Binary Stars." The Astrophysical Journal 835 (2): 145 [10.3847/1538-4357/835/2/145] [Journal Article/Letter]

2016. "Tidal decay and stable Roche-lobe overflow of short-period gaseous exoplanets." Celestial Mechanics and Dynamical Astronomy 126 (1-3): 227-248 [10.1007/s10569-016-9704-1] [Journal Article/Letter]

2014. "Predicting Lyensuremathalpha and Mg II Fluxes from K and M Dwarfs Using Galaxy Evolution Explorer Ultraviolet Photometry." Astrophysical Journal Letters 796 (1): L20 [10.1088/2041-8205/796/1/L20] [Journal Article/Letter]