MINERALOGY OF CERES’ FEJOKOO (AC-5) QUADRANGLE
1. What is the surface composition in this quadrangle?
2. How does it compare to the global composition of Ceres?
3. Is there a correlation between morphological features and surface composition?
4. What are the implications for the formation and evolution of Ceres’ surface?
Hughson et al. (2016, in prep) describe the terrain in Fejokoo as highly cratered  and it is suitably termed ancient. The largest crater, Fejokoo, is hexagonal in habit and 68 km mean diameter. Topography  reveals six tholi that are ~20 x 20 km in lateral extent and ~3 km high. Our analysis focuses on data returned from VIR  and displayed as spectral parameter maps as in  and ortho-rectified FC images comprising controlled photomosaics of Ceres . The spectral reflectance and significant spectral parameters are largely uniform across the region and consist of a relatively flat spectrum between 0.5-2.6 µm, a UV absorption edge shortward of 0.4 microns and a complex of near-IR absorptions that represent a mixture of ammoniated phyllosilicate, carbonates and a spectrally dark component that cannot be specifically identified . The crater Oxo stands out by the additional presence of water ice features  and at least five other small, bright spots show spectral variations from surrounding material of varying compositional significance. Ceres surface has been uniformly covered with dark clays and carbonates while exposure of materials from beneath the top-coating layer, at discrete locations have different spectral parameters and thus variable composition.
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