Multivariate approach for evaluating the composition of Meridiani spherules
Résumé
One of the reasons for selecting Meridiani Planum as one of the two landing sites for the MER (Mars Exploration Rover) mission was the detection of a hematite signature by the TES (Thermal Emission Spectrometer) instrument onboard MGS (Mars Global surveyor) [1]. The presence of hematite at Meridiani has since been confirmed by instruments of the Athena Science Payload of the Opportunity MER rover [2,3]. Meridiani plains appear to be sulphur-rich sedimentary layered rocks covered by basaltic soils (outcrops being exposed within impact craters) [3,4]. Ubiquitous mm-sized spherules, nicknamed 'blueberries', have been observed in both the rocks and the soils. Opportunity's mini-TES and Mössbauer spectrometer (MB) have shown that hematite is present both in the matrix of the layered rocks and in the spherules [2,3].