Geochemical and Biological Profiles of a Quartz Stone in the Qaidam Mars Analog Using LIBS: Implications for the Search for Biosignatures on Mars

Abstract

Biosignature detection is one of the most important goals in Mars exploration missions. Since the Mars Science Laboratory (MSL) mission, the laser-induced breakdown spectrometer (LIBS) has become an essential payload due to its convenience and versatility in profiling elemental chemistry, and the most recent rovers Perseverance and Zhurong both have one onboard for the chemical characterization at their landing sites on Mars. Here, we attempt to study whether and to what extent using LIBS spectral data is possible to differentiate biotic and abiotic chemical signals. A clastic quartz stone collected from a Mars analog setting, the western Qaidam Basin of western China, was selected for LIBS analysis. Raman spectroscopy was used as a detector of organic signals to support the presence of potential hypolithic communities and the dearth of epilithic biomass on the rock. This study constructs a pseudo-three-dimensional geochemical profile of the Qaidam analog quartz stone, a representative of rocks with relatively homogeneous mineral compositions and limited bulk nonuniformity that have previously been found on Mars (Smith and Bandfield,

Performance improvement of underwater LIBS qualitative and quantitative analysis by irradiating with long nanosecond pulses

“…As an emerging means of chemical analysis, laser-induced breakdown spectroscopy (LIBS) is a type of atomic emission spectroscopy that utilizes a high-power pulse laser focused on the target surface to produce a plasma, enabling the qualitative and quantitative analysis of sample compositions. 11,12 With the advantages of real-time and multi-element detection, and more importantly, non-contact and in situ detection, it provides a new technical means for on-site measurement, and this is also the reason why LIBS technology has been chosen for extreme conditions, 13,14 medical industry, 15,16 archaeology, 17,18 etc. Recently, underwater LIBS research has attracted widespread interest, revealing the fundamental mechanisms of laser-induced plasma in water and promoting the development of underwater LIBS instrumentation and associated technologies.…”