Crantor, a short-lived horseshoe companion to Uranus

TL;DR

This paper investigates the dynamical behavior and stability of the temporary horseshoe co-orbital Crantor with Uranus, exploring its past, present, and potential long-term orbital configurations.

Contribution

It provides a detailed dynamical analysis of Crantor's co-orbital motion with Uranus and identifies a new long-term horseshoe librator candidate, 2010 EU65.

Findings

Crantor currently follows a complex horseshoe orbit influenced by Uranus and Saturn.

Saturn significantly destabilizes Crantor's orbit through node precession.

2010 EU65 is identified as a potential long-term horseshoe librator candidate.

Abstract

Stable co-orbital motion with Uranus is vulnerable to planetary migration but temporary co-orbitals may exist today. So far only two candidates have been suggested, both moving on horseshoe orbits: 83982 Crantor (2002 GO9) and 2000 SN331. (83982) Crantor is currently classified in the group of the Centaurs by the MPC although the value of its orbital period is close to that of Uranus. Here we revisit the topic of the possible 1:1 commensurability of (83982) Crantor with Uranus and also explore its dynamical past and look into its medium-term stability and future orbital evolution. (83982) Crantor currently moves inside Uranus' co-orbital region on a complex horseshoe orbit. The motion of this object is primarily driven by the influence of the Sun and Uranus, although Saturn plays a significant role in destabilizing its orbit. The precession of the nodes of (83982) Crantor, which is accelerated by Saturn, controls its evolution and short-term stability. Although this object follows a temporary horseshoe orbit, more stable trajectories are possible and we present 2010 EU65 as a long-term horseshoe librator candidate in urgent need of follow-up observations. Available data indicate that the candidate 2000 SN331 is not a Uranus' co-orbital.