AAS 97-614

GALILEO EUROPA MISSION (GEM) TOUR DESIGN

J.L. Bell, J.R. Johannesen - Jet Propulsion Laboratory

Abstract

Galileo has received approval for a two-year follow-on mission, called the Galileo Europa Mission (GEM). A three-phase tour has been designed for GEM that includes eight Europa encounters, four Callisto flybys, and two Io encounters to end the GEM in December 1999. Although science desires for the satellite encounters were of primary importance to the tour design, the flyby conditions were also influenced by the gravity assist they could provide to the trajectory, since the propellant available is limited to that remaining after the prime mission. The tour design was also heavily influenced by the requirement to return to Io, since the radiation exposure that accompanies such a flyby may severely degrade the health of the spacecraft.