ON THE STABILITY OF MARTIAN TROJANS

Numerical integrations have been performed for several dozen Mars Troj an test particles in a self-consistent model of the solar system. The integration period exceeds 4 Myr. We study primarily the dependence of the stability of the motion on the particles' orbital inclination. Th e variational equations for the particles' orbits were also solved to study the chaoticity of the trajectories. Several interesting results emerge: (a) long-term stability for the particles appears possible onl y in well-defined ''inclination windows '' 15-degrees less-than-or-equ al-to i less-than-or-equal-to 30-degrees and 32-degrees less-than-or-e qual-to i less-than-or-equal-to 44-degrees with respect to Jupiter's o rbit. (b) The decisive perturbing and destabilizing influences seem to be simple secular resonances caused by Jupiter and/or Mars. These are tentatively identified. (c) The variational equation solutions do not indicate chaoticity before the actual destabilization occurs, so that the instability is a threshold phenomenon rather than due to sensitiv e dependence on initial conditions.