Friday

Central to our understanding of martian habitability is the availability of organic molecules (OM) since they form the basis of terrestrial life. The detection and characterisation of martian OM has been one of the main foci of martian exploration since the Viking lander era. This search has been successful both on Mars by Curiosity, where the SAM instrument detected thiophenes (Eigenbrode et al., 2018) and in martian meteorites (Steele et al., 2012).

The newest generation of rovers (ie. Perseverance and ExoMars) are equipped with nstrument suites onboard that are dedicated to OM detection such as SHERLOC (Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals, Perseverance) and MOMA (Mars Organic Molecule Analyser, ExoMars). However, the spatial and spectral resolution, and detection limits of such techniques are limited due to constraints such as power, rover mass, and space available onboard. Perseverance is paving the way for Mars Sample Return (and thus detection of lower OM concentrations and nanoscale analyses) in ~ 10 years time, and it is crucial that we maximise the scientific return from these precious specimens.

We have searched for and studied OM in the martian meteorites Nakhla, Lafayette and Tissint using a combination of bulk techniques (studying all the OM in a crushed chip) and in-situ methods (studying individual inclusions of OM in a thin section). In this session we will give an overview and comparison of the methods and results from two techniques we have used: XANES spectroscopy at Diamond Light Source, and Liquid Chromatography Mass Spectrometry at the University of Glasgow Polyomics Facility, which both provide structural information of low concentrations of OM in martian samples. We will explain how our results compare to Curiosity’s SAM data, the capabilities of SHERLOC and MOMA, as well as the implications of this work for Mars Sample Return.