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arXiv · 2512.20430

Second-species dynamics in the restricted planar circular three body problem: chaos, final motions and periodic orbits

Marcel Guardia·José Lamas·Tere M-Seara
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Abstract

Consider the Restricted Planar Circular Three Body Problem (RPC3BP), which models the motion of a massless particle (Asteroid) under the gravitational influence of two massive bodies (the primaries) moving on circular orbits. By considering the ratio between the masses of the primaries to be arbitrarily small, we construct orbits with close encounters with the smaller primary (Jupiter) that realize any combination of past and future final motions (in the sense of Chazy's), including oscillatory motions. We also obtain arbitrarily large ejection-collision orbits with Jupiter and ejection-collision orbits between the two primaries (Sun and Jupiter), as well as arbitrarily large periodic orbits that pass arbitrarily close to Jupiter. Our approach combines singular perturbation theory and Levi-Civita regularization near Jupiter, and McGehee regularization near infinity and near the Sun, together with a global analysis that leads to transverse intersections of invariant manifolds.

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Marcel Guardia, José Lamas, Tere M-Seara. 2025-12-23. Second-species dynamics in the restricted planar circular three body problem: chaos, final motions and periodic orbits. https://arxiv.org/abs/2512.20430

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