Post-landing major element quantification using SuperCam laser induced breakdown spectroscopy

The SuperCam instrument on the Perseverance Mars 2020 rover uses a pulsed 1064 nm laser to ablate targets at distance and conduct induced breakdown spectroscopy (LIBS) by analyzing light from resulting plasma. LIBS spectra are preprocessed remove ambient light, noise, continuum signal present in observations. Prior quantification, masked noisier spectrometer regions normalized minimize fluctuations effects of target distance. In some cases, also standardized or binned prior quantification. To determine quantitative elemental compositions diverse geologic materials Jezero crater, Mars, we use suite 1198 laboratory 334 well-characterized reference samples. samples were selected span wide range include typical silicate rocks, pure minerals (e.g., silicates, sulfates, carbonates, oxides), more unusual Mn ore sodalite), replicates sintered calibration (SCCTs) onboard rover. For each major element (SiO2, TiO2, Al2O3, FeOT, MgO, CaO, Na2O, K2O), database was subdivided into five “folds” with similar distributions interest. One fold held out as an independent test set, remaining four folds used optimize multivariate regression models relating spectrum composition. We considered variety models, several for further investigation element, based primarily root mean squared error prediction (RMSEP) when analyzed 3 m. cases comparable performance m, incorporated SCCT different distances choose preferred model. Shortly after landing collecting initial targets, one model per element. Subsequently, additional data revised ensure results that consistent geochemical constraints. discussed here is snapshot ongoing effort deliver most accurate chemical LIBS.