Optimizing the detection of carotene in cyanobacteria in a martian regolith analogue with a Raman spectrometer for the ExoMars mission

The Raman Laser Spectrometer (RLS) onboard ExoMars 2018 will perform measurements on Mars to identify organic compounds and mineral products as an indication of former and recent biological activity. The measurements will be performed on crushed powdered samples inside the Rover's ALD (Analytical Laboratory Drawer). Here we show the identification of β-carotene present in cyanobacteria with a Raman spectrometer under Mars analogue conditions and develop a procedure how to optimize their detection and the detection of various minerals in different types of martian soils. ► We performed Raman measurements on Mars analogue material with cyanobacteria. ► β-Carotene present in cyanobacteria could be discriminated from the mineral background. ► A measurement regime is proposed for martian analogue material with cyanobacteria.