L.T. Elkins-Tanton¹, E. Asphaug¹, *James F Bell¹, D. Bercovici², B.G. Bills³, R.P. Binzel⁴, W.F. Bottke⁵, G.M. Brown³, J. Goldsten⁶, R. Jaumann⁷, I. Jun³, D.J. Lawrence⁶, P. Lord⁹, S. Marchi⁵, T. McCoy⁸, D. Oh³, R.S. Park³, P.N. Peplowski⁶, C.A. Polanskey³, D. Potter⁹, T.H. Prettyman¹⁰, C.A. Raymond³, C.T. Russell¹¹, S. Scott⁹, H. Stone³, K.G. Sukhatme³, N.Z. Warner³, B.P. Weiss⁴, D.D. Wenkert³, M. Wieczorek¹², D. Williams¹, M.T. Zuber⁴ (1.Arizona State University, 2.Yale University, 3.Jet Propulsion Laboratory/California Institute of Technology, 4.Massachusetts Institute of Technology, 5.Southwest Research Institute, 6.Applied Physics Laboratory/Johns Hopkins University, 7.DLR/German Aerospace Center, 8.Smithsonian Institution, 9.Space Systems Loral, Inc., 10.Planetary Science Institute, 11.University of California, Los Angeles, 12.Observatoire de la Côte d'Azur)