The von Zeipel-Lidov-Kozai effect inside mean motion resonances with applications to trans-Neptunian objects

TL;DR

This paper develops a semi-analytical model to study the von Zeipel-Lidov-Kozai resonance within mean motion resonances, revealing long-term dynamical behaviors of trans-Neptunian objects and explaining observed orbital switching phenomena.

Contribution

It introduces a modified adiabatic invariant and a semi-secular model to analyze the ZLK effect inside MMRs, providing a new approach for long-term orbital predictions.

Findings

The model accurately predicts the long-term evolution of TNOs within MMRs.

2018 VO137 and 2005 SD278 show switching behaviors consistent with the model.

Good agreement between numerical simulations and phase portrait predictions.

Abstract

Secular dynamics inside MMRs plays an essential role in governing the dynamical structure of the trans-Neptunian region and sculpting the orbital distribution of trans-Neptunian objects (TNOs). In this study, semi-analytical developments are made to explore the von Zeipel-Lidov-Kozai (ZLK) resonance inside mean motion resonances (MMRs). To this end, a semi-secular model is formulated by averaging theory and then a single-degree-of-freedom integrable model is achieved based on the adiabatic invariance approximation. In particular, we introduce a modified adiabatic invariant, which is continuous around the separatrices of MMRs. During the long-term evolution, both the resonant Hamiltonian and the adiabatic invariant remain unchanged, thus phase portraits can be produced by plotting level curves of the adiabatic invariant with given Hamiltonian. The phase portraits provide global pictures to predict long-term behaviors of the eccentricity, inclination and argument of pericenter. Applications to some representative TNOs inside MMRs (2018 VO137, 2005 SD278, 2015 PD312, Pluto, 2004 HA79, 1996 TR66 and 2014 SR373) show good agreements between the numerically propagated trajectories under the full N-body model and the level curves arising in phase portraits. Interestingly, 2018 VO137 and 2005 SD278 exhibit switching behaviors during the long-term evolution and currently they are inside 2:5 MMR with Neptune.