Characterization of Mineral Targets by Laser Desorption and Ionization in Preparation of the MOMA Investigation Onboard the ExoMars-2018 Rover

The MOMA instrument (Mars Organic Molecule Analyzer [1]) onboard the ESA-Roskosmos led ExoMars-2018 rover mission shall investigate Martian near-surface samples by Laser De-sorption and Ionization (LDI). This experimental technique uses UV laser impact to ablate molecular fragments that shall be analyzed by mass spectrometry and is thus geared towards characterization of the organic inventory in Martian subsurface samples. Here we present an end-to-end LDI experiment performed on a small (though diverse) set of terrestrial inorganic samples (minerals). The experiment has the following goals: (1) explore the possibility to identify minerals by LDI, (2) characterize the physical interaction between laser and mineral by measuring the average mass of ablated material per laser shot, and (3) present data acquired by the MOMA engineering test unit (ETU) at NASA GSFC. The recorded mass peaks are part of the " background " that will be encountered during any in situ measurement on the surface of Mars and in which peaks of organic compounds are embedded. Hence such data contribute to a reference data set that will be important to interpret complex spectra of any organic-bearing sedimentary rocks on Mars.