Extrasolar Kuiper Belts

TL;DR

This paper reviews the current understanding of extrasolar Kuiper belts, comparing their properties and structures with our Solar System's Kuiper belt, based on recent observational data from IR and high-resolution imaging.

Contribution

It provides a comprehensive overview of observational evidence and structural features of extrasolar Kuiper belts, highlighting similarities and differences with our Solar System.

Findings

Approximately 20% of stars host detectable debris disks.

Structures in some disks suggest planetary influences similar to Solar System dynamics.

Presence of CO gas indicates volatile-rich planetesimal destruction.

Abstract

Extrasolar debris disks are the dust disks found around nearby main sequence stars arising from the break-up of asteroids and comets orbiting the stars. Far-IR surveys (e.g., with Herschel) showed that ~20% of stars host detectable dust levels. While dust temperatures suggest a location at 10s of au comparable with our Kuiper belt, orders of magnitude more dust is required implying a planetesimal population more comparable with the primordial Kuiper belt. High resolution imaging (e.g., with ALMA) has mapped the nearest and brightest disks, providing evidence for structures shaped by an underlying planetary system. Some of these are analogous to structures in our own Kuiper belt (e.g., the hot and cold classical, resonant, scattered disk and cometary populations), while others have no Solar System counterpart. CO gas is seen in some debris disks, and inferred to originate in the destruction of planetesimals with a similar volatile-rich composition to Solar System comets. This chapter reviews our understanding of extrasolar Kuiper belts and of how our own Kuiper belt compares with those of neighbouring stars.