À có một trường hợp khá hay(theo NASA):
Will Pluto and Neptune ever collide?
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Probably not...at least not for the next 750 million years or so. Using a special-made computer called a 'Digital Orrery' the celestial mechanics of the solar system were simulated at 40 day intervals over the next billion years or so. Pluto was found to be in a 'chaotic' orbit, but one that would not take Pluto closer than tens of millions of miles from Neptune. This line of investigation has also turned up the troubling prediction that Mars or Mercury could be ejected from the solar system because of their elliptical orbits and the cumulative effects of chaotic perturbations added up over billions of years. Also, by simply shifting the start position of Mars by a kilometer, the location of Pluto in its orbit was changed by one half of an orbit, which shows how sensitive the dynamics of the solar system are to slight changes in its initial conditions. Astronomers now worry that solar systems as benign as ours for life, may be rare, if planetary systems are so precariously balanced.