Destruction of Binary Minor Planets During Neptune Scattering

TL;DR

This paper investigates how Neptune scattering events affect binary minor planets, concluding that such events tend to destroy wide binaries, implying they formed through gentler processes or in situ.

Contribution

It provides the first detailed analysis of binary destruction during Neptune scattering, challenging existing models of Kuiper Belt formation.

Findings

Wide binaries are efficiently destroyed by Neptune scattering.

The cold Kuiper Belt's binaries likely formed in situ or via gentle mechanisms.

Abstract

The existence of extremely wide binaries in the low-inclination component of the Kuiper Belt provides a unique handle on the dynamical history of this population. Some popular frameworks of the formation of the Kuiper Belt suggest that planetesimals were moved there from lower semi-major axis orbits by scattering encounters with Neptune. We test the effects such events would have on binary systems, and find that wide binaries are efficiently destroyed by the kinds of scattering events required to create the Kuiper Belt with this mechanism. This indicates that a binary-bearing component of the cold Kuiper Belt was emplaced through a gentler mechanism or was formed in situ.