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Is it possible to have 2 celestial objects sharing the same orbit and never collide? Like 2 planets of the same mass.
Sure, if the planets are exactly opposite to each other and of the same mass, the symmetry of the problem says that they will stay exactly opposite. Tiny perturbations. e.g. one planet being just a bit closer to the star, will create problems however. In that case, the closer planet would have a shorter orbital period, and would end up grazing the farther planet.
(published on 03/27/2011)
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