Sean C. Solomon, Ralph L. McNutt, Jr., Peter D. Bedini, Brian J. Anderson, David T. Blewett, Larry G. Evans, Robert E. Gold, Stamatios M. Krimigis, Scott L. Murchie, Larry R. Nittler, Roger J. Phillips, Louise M. Prockter, James A. Slavin, and Maria T. Zuber, Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road, N.W., Washington, DC 20015, USA (scs@dtm.ciw.edu); Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA; Computer Sciences Corporation, Lanham-Seabrook, MD 20706, USA; Academy of Athens, Athens 11527, Greece; Southwest Research Institute, Boulder, CO 80302, USA; Heliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA; Department of Earth, Atmospheric and Planetary Sciences, MIT, Cambridge, MA 02129, USA.