Mission Objectives Overview                                                   ===========================                                                                                                                               The specific Dawn science objectives by instrument are as follows.                                                                                          Framing Camera                                                                --------------                                                                                                                                              1. To determine the origin and evolution of Vesta and Ceres by mapping        the extent of geologic processes on the asteroid surfaces, and by using       the cratering record to establish a relative chronology of the crustal        units and population of impactors in the early solar system.                                                                                                2. To map the shape, determine the spin state, and establish the degree       of cratering of the asteroids visited.                                                                                                                      3. To map the topography of Vesta and Ceres.                                                                                                                4. To search for dust and satellites in the environment of the                asteroids visited.                                                                                                                                          5. To provide a geologic, compositional and geophysical context for           the HED meteorites.                                                                                                                                         6. To provide an opportunity to identify Ceres-derived meteorites             in their geologic context.                                                                                                                                                                                                                Visible and Infrared Mapping Spectrometer                                     -----------------------------------------                                                                                                                   1. To provide a geologic, compositional and geophysical context for           the HED meteorites.                                                                                                                                         2. To provide an opportunity to identify Ceres-derived meteorites in          their geologic context.                                                                                                                                     3. To map the thermophysical properties of Vesta and Ceres.                                                                                                 4. To determine the origin and evolution of Vesta and Ceres by                mapping the mineralogical composition and its spatial variation               across the asteroidal surface.                                                                                                                                                                                                            Gamma Ray and Neutron Detector                                                ------------------------------                                                                                                                              1. To map the major elemental composition of O, Si, Fe, Mg, Ti, Al,           Ca, and H on Vesta and Ceres.                                                                                                                               2. To map the trace elements U, Th, K, Gd and Sm on Vesta and Ceres.                                                                                        3. To provide a geologic, compositional and geophysical context for           the HED meteorites.                                                                                                                                                                                                                       Gravity science                                                               ---------------                                                                                                                                             1. To determine the masses of the asteroids visited.                                                                                                        2. To measure the bulk density of Vesta and Ceres, in conjunction             with topography, and determine its heterogeneity.                                                                                                           3. To determine the gravitational fields of Vesta and Ceres.                                                                                                The above science goals are extracted from the Dawn Science Plan              (Raymond 2007).  Specific science measurement requirements necessary          to meet the stated science goals are outlined in the same document,           as well as in Rayman et al. (2006).