Jupiter's Metastable Companions

Sarah Greenstreet; Brett Gladman; Mario Juric

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arXiv · 2309.06609

Jupiter's Metastable Companions

Sarah Greenstreet·Brett Gladman·Mario Juric

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Abstract

Jovian co-orbitals share Jupiter's orbit in 1:1 mean motion resonance. This includes $>$10,000 so-called Trojan asteroids surrounding the leading (L4) and trailing (L5) Lagrange points, viewed as stable groups dating back to planet formation. Via a massive numerical study we identify for the first time some Trojans which are certainly only `metastable'; instead of being primordial, they are recent captures from heliocentric orbits into moderately long-lived (10 kyr - 100 Myr) metastable states that will escape back to the scattering regime. We have also identified (1) the first two jovian horseshoe co-orbitals that exist for many resonant libration periods, and (2) eight jovian quasi-satellites with metastable lifetimes of 4-130 kyr. Our perspective on the Trojan population is thus now more complex as Jupiter joins the other giant planets in having known metastable co-orbitals which are in steady-state equilibrium with the planet-crossing Centaur and asteroid populations, in agreement with theoretical estimates.

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Sarah Greenstreet, Brett Gladman, Mario Juric. 2023-09-12. Jupiter's Metastable Companions. https://arxiv.org/abs/2309.06609

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