12th Nov 2012 Sol 96

The science team rotates roles and I am Mineralogy Science Theme Lead for the next few sols.  We will consider  science priorities, the availability of time to do science experiments, the positioning of instruments and what samples we could reach, together with the power budget.    Currently Curiosity is doing a range of experiments with the Gas Chromatography- Mass Spectrometer that is at the heart of SAM.  This instrument allows us to efficiently discriminate different compounds and make isotopic measurements as well.  If our daily budget of time and power availability allows, we make measurements with other instruments as well.  Its important to get complementary analyses from the different instruments – for instance APXS and ChemCam tell us about the major element composition of rocks, minerals  and soil (Si, Ti, Al, Fe, Mn, Mg, Fe, Ca, Na, K, P, S), CHEMIN uses X-ray diffraction to tell us a mineral’s identity and SAM can tell us about what molecular compounds containing these elements and also C, H, O, N are present.  

Accurately understanding the isotopic composition of (C,H,O,N) carbon, hydrogen, oxygen, opens up new ways of looking at the samples that Curiosity encounters.  For instance, enrichment in C-12 (ie a carbon atom that has a nucleus of 12 atomic mass units) is a sign of organic material.  Enrichment in C-13 is a sign that material has trapped C02 from the atmosphere.