Description: We propose a low SWaP Capillary Absorption Spectrometer (CAS) which has general applicability to a range of NASA missions with specific development for methane analysis during an Enceladus plume flythrough. The system will contain a Plume Capture and Delivery System (PCDS) which transports plume molecules to the CAS to be analyzed for 13C/12C carbon and D/H hydrogen isotope ratios. The CAS utilizes laser absorption spectroscopy in a proprietary hollow fiber gas cell to enable high-precision measurements with minimal sample volume, making it ideal for a plume flythrough. This proposed effort will specifically design a PCDS and develop the CAS further to strengthen the D/H analysis with the constraints of relatively low-abundance of deuterated methane, along with the need to also measure 13C/12C isotopes jointly. In addition, the proposed technology will enable a general and significant upgrade to the core CAS technology (CAS V2.0) with the development of a higher performance, modular, multi-laser design.

Benefits: Isotope-ratio analysis is a powerful tool to elucidate planetary systems. CAS is a novel technology that analyzes small sample amounts to produce high precision data enabling isotope measurement in a flythrough environment where the sample is extremely limited. For example, measurements of methene isotope ratios in a plume of Enceladus can provide insight into the possibility of life below the surface. In addition, the low sample-volume, sensitive, and low SWaP instrument can be appealing for a wide range of NASA lunar and planetary missions.

By expanding the CAS capability to measure D/H ratios in methane, the technology will be attractive for a range of environmental sensing and energy applications. In addition, the lower size, weight, power, AND cost is appealing as an alternative to isotope ratio mass spectrometry for commercial applications including pharmaceuticals, food provenance, and forensics.