Planetesimals in Debris Disks

TL;DR

This paper reviews how debris disks formed from planetesimal collisions reveal insights into planetary system formation and evolution over billions of years, despite the difficulty of observing the original planetesimals directly.

Contribution

It provides a comprehensive overview of planetesimal formation, debris disk observations, and their significance in understanding planetary system development.

Findings

Debris disks trace planet formation processes over 100 Myr.

Dust production and dynamics are key to interpreting observations.

Extrasolar debris shows both similarities and differences to Solar System dust.

Abstract

Planetesimals form in gas-rich protoplanetary disks around young stars. However, protoplanetary disks fade in about 10 Myr. The planetesimals (and also many of the planets) left behind are too dim to study directly. Fortunately, collisions between planetesimals produce dusty debris disks. These debris disks trace the processes of terrestrial planet formation for 100 Myr and of exoplanetary system evolution out to 10 Gyr. This chapter begins with a summary of planetesimal formation as a prelude to the epoch of planetesimal destruction. Our review of debris disks covers the key issues, including dust production and dynamics, needed to understand the observations. Our discussion of extrasolar debris keeps an eye on similarities to and differences from Solar System dust.