  ExoFit trials are field campaigns financed by ESA to test the Rosalind
Franklin rover and to enhance collaboration practices between ExoMars working
groups. During the first trial, a replicate of the ExoMars rover was remotely
operated from Oxfordshire (United Kingdom) to perform a complex sequence of
scientific operation at the Tabernas Desert (Spain). By following the ExoMars
Reference Surface Mission (RSM), the rover investigated the Badlands subsoil
and collected drill cores, whose analytical study was entrusted to the RLS
(Raman Laser Spectrometer) team. The preliminary characterization of core
samples was performed in-situ through the RLS Engineering and Qualification
Model (EQM-2) and the Raman Demonstrator (RAD1), being this a new, portable
emulator of the RLS. In-situ results where then complemented by laboratory
analysis using the RLS ExoMars simulator and the commercial version of the
Curiosity/CheMin XRD system. Raman data, obtained by closely simulating the
operational constraints of the mission, successfully disclosed the
mineralogical composition of the samples, reaching the detection of minor/trace
phases that were not detected by XRD. More importantly, Raman analysis detected
many organic functional groups, proving the presence of extremophile organisms
in the arid sub-surface of the Tabernas Desert. In light of the forthcoming
ExoMars mission, the results here presented proves that RLS could play a
critical role in the characterization of Martian sub-surface environments and
in the analytical detection of potential traces of live tracers.
