Shaping of the inner Oort cloud by Planet Nine

TL;DR

This paper uses numerical simulations to explore how Planet Nine influences the structure of the inner Oort cloud, revealing the formation of a spherical and inclined disk that could be a source of comets.

Contribution

It demonstrates how Planet Nine's secular and resonant interactions shape the inner Oort cloud, providing a new understanding of its morphology and comet production.

Findings

Planet Nine induces a spherical structure in the inner Oort cloud.

The structure's morphology differs from star fly-by scenarios.

Predicted comet production rate is detectable.

Abstract

We present a numerical simulation of the dynamical interaction between the proposed Planet Nine and a debris disk around the Sun for $4{\rm Gyr}$, accounting for the secular perturbation of the four giant planets in two scenarios: (a) an initially thin circular disk around the Sun (b) inclined and eccentric disk. We show, in both scenarios, that Planet Nine governs the dynamics in between $1000{\rm -5000{\rm AU}}$ and forms spherical structure in the inner part ($\sim1000{\rm AU}$) and inclined disk. This structure is the outcome of mean motion resonances and secular interaction with Planet Nine. We compare the morphology of this structure with the outcome from a fly-by encounter of a star with the debris disk and show distinct differences between the two cases. We predict that this structure serves as a source of comets and calculate the resulting comet production rate to be detectable.