aracterized by their song dependence on initial conditions.
from that point of view， many of the previous long-term numerical integrations included only the outer five planets (sussman & wisdom 1988; kinoshita & nakai 1996). this is because the orbital periods of the outer planets are so much longer than those of the inner four planets that it is much easier to follow the system for a given integration period. at present， the longest numerical integrations publishe