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L. Marinangeli, A. Baliva, E. Piluso, G.G. Ori (IRSPS, Italy), I. Casanova (IEEC, Spain), A. Lenti, C. Ponzoni, E. Cavazzutti, L. Isabella (LABEN S.p.A., Italy)
The chemistry measured by XRF and APX during previous mission to Mars yielded rich information on certain aspects of Martian materials but cannot constrain the exact mineral assemblages and as a result, neither the genesis of the rocks or soils. For example, in some cases, a volcanic rock, a sedimentary rock, and a metamorphic rock can have the same chemical composition. Therefore in order to assess the Martian environment in which the rock or soil was produced, we need to perform analysis of the mineralogy of the material. For this purpose, we propose an X-Ray Instrument for Mineralogical Analysis of Planetary surface materials (XMAP) for Mars 2005 mission. Basically, XMAP will consist of an X-ray source, a sample holder and a CCD detector. The diffraction technique is based on the capability of atom lattices to diffract incident X-ray beams. The diffracted X-rays interfere each other and only the beams that interfere positively can reach the detector. The instrument may be also thought to be arranged for both a lander or a rover configuration with a few minor adaptive changes. XMAP will perform a no destructive analysis and a preparation of the sample is not required. We are planning to be able to discriminate a high range of minerals from clay or phyllosilicates, characterised by high interplanar lattice distance, to oxides and carbonates or evaporites. This rock spectrum is what we expect for exobiological exploration of Mars 2005 landing site. In addition, with XRD it is possible to identify the presence of water ice or dioxide ice; in fact, they give a different characteristic peak in the diffractometer spectrum. The same X-Ray source and detector for diffractometry analysis can be used for X-ray fluorescence combining the two methods and giving an accurate petrologic characterisation of rock sample.
The author(s) of this abstract have provided an email address for comments about the abstract: luciam@sci.unich.it