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I am a postdoctoral fellow in the Girguis Lab at Harvard University. My research explores the biogeochemistry and ecophysiology of SLiMEs – Subsurface Lithoautotrophic Microbial Ecosystems – as a proxy for investigating the astrobiological potential of other worlds. My work often combines multiple tools, including tracer experiments, imaging, 'omics, and metabolic modeling, to explore the habitable limits of life and the metabolic strategies it employs to survive the biotic fringe. When I'm not working with SLiMEs, methanogenic archaea (methane-producing microbes) are my favorite model organisms for astrobiology-related research.

  More broadly, my work is motivated by the quest to explore the biotic fringe as a means to better constrain the physical, geochemical, and molecular parameters that define the limits of habitability for life as we know it. To put it in simpler terms, I want to help answer one question: are we alone in the Universe? 

Please check back for updates!
Last update: 19 April 2023

Want to learn more? Check out my 2020 Ph.D. defense, brought to you by COVID-19.

Session Chair

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Session P25C 
The New Mars Underground:




Meet Collaborators


Fjaðrárgljúfur (Feather River Canyon), Iceland

© 2016 by Rachel L. Harris

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