Dynamical evolution of planetesimals driven by a massive planet: First simulations

N-body simulations of the dynamical evolution of proto-planets embedded in a swarm of planetesimals and perturbed by a massive Jupiter-like planet wer e performed with the GRAPE-4 system recently installed in Marseille observa tory. Initially both the proto-planets and the planetesimals are on circula r and coplanar orbits distributed in a ring located within the orbital radi us of the perturber. The first simulations show that, for a perturber signi ficantly more massive than Jupiter, the system of the proto-planets becomes strongly unstable with the possibility of orbit crossing. (C) 1999 Elsevie r Science Ltd. All rights reserved