Rachel L. Harris

Rachel L. Harris, Ph.D., is a Deep Biosphere Microbial Ecologist and Biogeochemist affiliated with Harvard University and NASA. As a research associate in the Girguis Lab and a NASA Postdoctoral Management Program Fellow, her work focuses on the ecophysiology of extremophiles in reducing environments, including hydrothermal features, deep subseafloor sediments, and saline terrestrial fracture fluids. She contributes to the NASA Astrobiology Program’s Network for Ocean Worlds and the Mars Sample Return Campaign Science Group, addressing questions about extraterrestrial habitability through microbial methane metabolism studies and redox gradient modeling on Enceladus and Europa.

• Key Roles: NASA Astrobiology Program, Girguis Lab (Harvard), Mars Sample Return Campaign Science Group
• Research Themes: Microbial ecophysiology, biosignature potential, extremophile biogeochemistry

She co-leads the Faculty of Arts and Sciences Postdoctoral Association (FASPDA) at Harvard, advocating for postdoctoral scholars. Her work bridges Earth’s extreme ecosystems with astrobiological exploration strategies for ocean worlds.