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A.R. Dobrovolskis (UCSC), J.L. Alvarellos (Space Systems Loral), K. Zahnle (ARC)
By now many studies have been made of the orbital stability and fate of asteroids, comets, and Kuiper Belt objects, both real and virtual (e.g., Wisdom and Holman, A.J. 102, 1258, 1991). Although simulation of a satellite system presents somewhat different problems from a planetary system, preliminary studies also have been made of hypothetical material orbiting Saturn (Burns and Gladman, Planet. Space Sci. 46, 1401, 1998). However, the dynamical environment of the Jovian system has not been explored until now.
Using the SWIFT integrator of Levison and Duncan (Icarus 108, 18, 1994), we have simulated small particles orbiting Jupiter in the presence of the Galilean satellites Io, Europa, Ganymede, and Callisto. Perturbations from Jupiter's oblateness (J2 and J4) and from the Sun were also included. Particles were started at random longitudes in prograde circular orbits in the plane of Jupiter's equator. Of 400 particles spread uniformly in semimajor axis from 3.28 to 32.61 Jupiter radii (from inside Io to outside Callisto), only 259 survived for the 9638-year duration of the simulation. All of the other 141 collided with a Galilean moon; none hit Jupiter itself, or escaped the Jovian system.
Most particle removals outside the immediate vicinity of a moon are attributed to low-order mean-motion resonances. In contrast, 1:1 resonances (Trojan, tadpole, and horseshoe-type orbits) proved quite stable on the 10000-year timescale. Except for such co-orbital particles, each satellite rapidly cleared its own ``chaotic zone'' where high-order resonances overlap (Wisdom, A.J. 85, 1122, 1980.)
JLA acknowledges the advice of Luke Dones and the support of the San Jose State U. Foundation. ARD thanks Jack Lissauer for advice and support.