In-Situ Extreme Environment Isotope Ratiometer

This Small Business Innovation Research project concerns the novel application of cavity-enhanced absorption spectroscopy to determine isotope ratios of carbon dioxide, methane, and water vapor in extreme environments. These environments, which include deep-sea hydrothermal vents, ocean boreholes, underwater volcanoes, and terrestrial aquifers, are of interest to the NASA Ames Astrobiology Group because they may harbor subsurface microbiological ecosystems, whose occurrences can be detected by measuring such isotope ratios. In Phase I, we have demonstrated the technical feasibility of making all three of these ratio measurements in a single, multiplexed instrument using both simulated and actual biogenically-generated gas samples. These ratios have been determined to better than 0.2%, which is sufficient to determine the presence of biological activity. The Phase II effort will consist primarily of packaging the instrument for extreme environments and subsequent field-testing in conjunction with NASA. The final Phase II prototype will be delivered to the NASA Ames Astrobiology Group. This instrument will be the first remotely operable sensor capable of measuring isotope ratios with sufficient precision to indicate the presence of biological activity in a variety of extreme environments.