Orbital properties of binary minor planets

TL;DR

This paper analyzes the orbital characteristics of binary minor planets in the Solar system, revealing their high inclinations and eccentricities, which suggest a dense collisional environment influenced their evolution.

Contribution

It provides a comprehensive analysis of the orbital properties of BMPs, highlighting their inclination and eccentricity distributions and implications for their formation and evolution.

Findings

BMPs are highly inclined relative to their orbit around the Sun.

BMPs not affected by tidal forces have high, non-thermal eccentricities.

Orbital properties suggest evolution in a dense collisional environment.

Abstract

Many binary minor planets (BMPs; both binary asteroids and binary Trans-Neptunians objects; TNOs) are known to exist in the Solar system. The currently observed orbital and physical properties of BMPs hold essential information and clues about their origin, their evolution and the conditions underwhich they evolved. Here we study the orbital properties of BMPs with currently known orbital solutions (the BMPs mutual orbits and not the BMP orbits around the sun). We find that BMPs are typically highly inclined relative to their orbit around the sun, with a distribution consistent with an isotropic distribution. BMPs not affected by tidal forces are found to have high eccentricities with non-thermal eccentricity distribution peaking at intermediate eccentricities (typically 0.4-0.6). The high inclinations and eccentricities of the BMPs suggest that BMPs evolved in a dense collisional environment, in which gravitational encounters in addition to tidal and secular Kozai affects played an important role in their orbital evolution.