Kozai-Lidov Resonant Behavior among Atira-class Asteroids

TL;DR

This paper investigates how Kozai-Lidov resonance influences the long-term orbital stability of Atira-class asteroids, revealing a mechanism that helps explain their stable orbits despite crossing Venus's path.

Contribution

It demonstrates that Kozai-Lidov resonance plays a key role in stabilizing Atira asteroids' orbits, a novel insight into their dynamical behavior.

Findings

Kozai-Lidov resonance affects some Atira asteroid orbits

Resonance contributes to their long-term stability

Orbital configurations with perihelion and aphelion nodes are common

Abstract

Atira-class asteroids have aphelia greater than 0.718 au and smaller than 0.983 au. It has been found that the orbits of many of them remain relatively stable for at least 1 Myr, but it is unclear what can make them so stable when they cross the orbit of Venus and some may reach, in heliocentric terms, as far as Earth's perihelion and as close as inside Mercury's perihelion. The analysis of their orbits shows that many of them have values of the argument of perihelion close to 0 or 180 degrees. Such an orbital arrangement means that the nodes are located at perihelion and at aphelion, i.e. for many known Atiras, away from the path of Venus. Here, we show that the orbits of some Atiras are strongly affected by the Kozai-Lidov resonance, which translates into enhanced long-term stability.