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SARAH S. JOHNSON | Principal Investigator


Sarah Stewart Johnson is an assistant professor of planetary science at Georgetown University and a visiting scientist at NASA’s Goddard Space Flight Center. She holds a B.A. in mathematics and environmental studies from Washington University in St. Louis, a second B.A. in philosophy, politics and economics and M.Sc. in biology from Oxford University, and a Ph.D. in planetary science from the Massachusetts Institute of Technology. Prior to joining Georgetown faculty, she was a Junior Fellow in the Harvard Society of Fellows.


Sarah's research is driven by the goal of understanding the presence and preservation of biosignatures within planetary environments. She is also involved in the implementation of planetary exploration, analyzing data from current spacecraft and devising new techniques for future missions. Her recent projects have included searching for signs of habitability with the Curiosity Rover, studying the limits of life in Antarctica, assessing how biology affects patterns of mineralization in Mars analog environments, and helping to develop sequencing as a tool for spaceflight.


HEATHER GRAHAM | Deputy Principal Investigator


Heather Graham is an organic geochemist with widely varied research experience ranging from paleoecology to phytochemistry to astrobiology. They have a B.A. in Chemistry from Occidental College and a dual-title Ph.D. from The Pennsylvania State University in Geosciences and Biogeochemistry. In addition to their research on deuterium enrichment patterns in extraterrestrial materials and the origin of hydrocarbons in space, they also provide support to the Mars Curiosity Rover science team developing analog materials for instrument testing, and also studies deuterium enrichment patterns in extraterrestrial materials to learn more about the origin of hydrocarbons in space.


Heather is profoundly curious about the natural world, the history of life, the vast connections between biotic and abiotic systems, and what evolution can tell use about our future. Before planetary science they studied the evolution of land plants and their adaptations to light. Heather is an active science communicator with collaborations in art, theater, and digital media. They like to think of science as a cultural product, a reflection of our collective values and dreams, a conversation between society and the the knowledge we have learned of the Universe. Their favorite organism is lichen.

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