Surface Composition of Vesta: Issues and Integrated Approach

The instruments on the Dawn spacecraft are exceptionally well suited to characterize and map the surface composition of Vesta in an integrated manner. These include a framing camera with multispectral capabilities, a high spectral resolution near-infrared imaging spectrometer, and a gamma-ray and neutron spectrometer. Three examples of issues addressed at Vesta are: (1) What is the composition of Vesta�s interior and differentiation state as exposed by the Great South Crater? (2) How has space weathering affected Vesta, both globally and at a local scale? and (3) Are volatiles or hydrated material present on Vesta�s surface? We predict that Dawn finds many surprises, such as an olivine-bearing mantle exposed near the south-pole, a weakly or un-weathered surface that has been relatively recently resurfaced, and a very thin layer of surficial volatiles derived from interaction with the solar wind