Chaotic dynamics in the (47171) Lempo triple system

TL;DR

This study models the complex 3D dynamics of the triple system (47171) Lempo, revealing its chaotic and unstable nature under current conditions, but potential stability through tidal effects, emphasizing the need for further observations.

Contribution

We developed a comprehensive 3D N-body model including orbital and spin evolution of triaxial bodies, providing new insights into the system's chaotic behavior and stability mechanisms.

Findings

The Lempo system's current best-fit orbit is chaotic and short-term unstable.

Tidal dissipation can stabilize the system's orbits.

System dynamics depend on many currently unknown parameters.

Abstract

We investigate the dynamics of the (47171) Lempo triple system, also known by 1999TC$_{36}$. We derive a full 3D $N$-body model that takes into account the orbital and spin evolution of all bodies, which are assumed triaxial ellipsoids. We show that, for reasonable values of the shapes and rotational periods, the present best fitted orbital solution for the Lempo system is chaotic and unstable in short time-scales. The formation mechanism of this system is unknown, but the orbits can be stabilised when tidal dissipation is taken into account. The dynamics of the Lempo system is very rich, but depends on many parameters that are presently unknown. A better understanding of this systems thus requires more observations, which also need to be fitted with a complete model like the one presented here.