Chaotic Disintegration of the Inner Solar System

TL;DR

This paper investigates the long-term chaotic evolution of Mercury and the inner Solar System, providing an analytical model to estimate the timescale for potential system disintegration, with implications for extrasolar planetary systems.

Contribution

It introduces a simple analytical model explaining Mercury's chaotic behavior and estimates the Solar System's dynamical lifetime, advancing understanding of planetary system stability.

Findings

Model aligns with numerical simulations

Estimates the Solar System's chaos transition timescale

Applicable to extrasolar planetary systems

Abstract

On timescales that greatly exceed an orbital period, typical planetary orbits evolve in a stochastic yet stable fashion. On even longer timescales, however, planetary orbits can spontaneously transition from bounded to unbound chaotic states. Large-scale instabilities associated with such behavior appear to play a dominant role in shaping the architectures of planetary systems, including our own. Here we show how such transitions are possible, focusing on the specific case of the long-term evolution of Mercury. We develop a simple analytical model for Mercury's dynamics and elucidate the origins of its short term stochastic behavior as well as of its sudden progression to unbounded chaos. Our model allows us to estimate the timescale on which this transition is likely to be triggered, i.e. the dynamical lifetime of the Solar System as we know it. The formulated theory is consistent with the results of numerical simulations and is broadly applicable to extrasolar planetary systems dominated by secular interactions. These results constitute a significant advancement in our understanding of the processes responsible for sculpting of the dynamical structures of generic planetary systems.