Many systems (including the Solar System) are stable over short time periods, but the stability of the Solar System is actually unknown over longer time periods

Many systems (including the Solar System) are stable over short time periods, but the stability of the Solar System is actually unknown over longer time periods. As an example, one of the numerical experiments Scott Tremaine has done has been to simulate the solar system, but to perturb the initial conditions of the planets by 1mm (that's one millimeter!). Over ~100 million years, in ~1% of systems Mercury actually crashes into Venus! [1] [1] http://www.ias.edu/about/publications/ias-letter/articles/2011-summer/solar-system-tremaine http://www.ias.edu/about/publications/ias-letter/articles/20...