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Behavior of Apsidal Orientations in Planetary Systems

Rory Barnes·Richard Greenberg
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Abstract

A widely considered characteristic of extra-solar planetary systems has been a seeming tendency for major axes of adjacent orbits to librate in stable configurations. Based on a new catalog of extra-solar planets (Butler et al. 2006) and our numerical integrations, we find that such small amplitude oscillations are actually not common, but in fact quite rare; most pairs of planets' major axes a re consistenet with circulating relative to one another. However, the new result s are consistent with studies that find that two-planet systems tend to lie near a separatrix between libration and circulation. Similarly, in systems of more than two planets, many adjacent orbits lie near a separatrix that divides modes of circulation.

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Rory Barnes, Richard Greenberg. 2006-10-11. Behavior of Apsidal Orientations in Planetary Systems. https://doi.org/10.1086/510068

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