Synergistic Observations between Cassini-Huygens and Earth-Orbital and Ground-Based Observatories and Relevant Laboratory Studies

The Cassini spacecraft was launched in October, 1997. Since then it has been flying on an interplanetary trajectory to Saturn. En route, Cassini has flown by Venus, the Earth, and Jupiter. Each of these events yielded new scientific results. (e.g., 11 papers in J. Geophys. Res. 106, 30099-30279.) The Cassini flyby of Jupiter, with Galileo already in jovian orbit, enabled the first-ever simultaneous measurements by two spacecraft at an outer planet. This fortuitous event provided a unique opportunity for synergistic observations of the giant planet's magnetic field and the properties of the jovian system using Galileo, Hubble, Chandra, and ground-based observatories. The results were stunning (e.g., 8 articles in Nature 415, 965-1005, February 28, 2002). The opportunity now exists to do the same for Saturn. Opportunities for synergistic observations will be pointed out. Of note are the dates of July 1, 2004 when Cassini goes into orbit about Saturn and January 14, 2005 when Huygens enters and descends through the atmosphere, ultimately reaching the surface of Titan. Opportunities also exist for relevant laboratory studies to characterize the properties of materials and to study chemical reactions which Cassni-Huygens may observe and/or measure. Some examples of relevant laboratory studies will be illustrated. The Cassini-Huygens mission is a joint undertaking by NASA and ESA, with ASI as a partner via a bilateral agreement with NASA.