Collisional Formation and Modeling of Asteroid Families

TL;DR

This paper reviews numerical simulations of asteroid collisions that have advanced understanding of asteroid family formation, highlighting how catastrophic disruptions and gravitational reaccumulation shape family properties and internal structures.

Contribution

It presents comprehensive simulation results that reproduce asteroid family characteristics and provide insights into their formation processes and internal structures.

Findings

Simulations reproduce sizes and velocities of asteroid family members.

Gravitational reaccumulation explains large asteroid members.

Constraints on family history and internal structure derived.

Abstract

In the last decade, thanks to the development of sophisticated numerical codes, major breakthroughs have been achieved in our understanding of the formation of asteroid families by catastrophic disruption of large parent bodies. In this review, we describe numerical simulations of asteroid collisions that reproduced the main properties of families, accounting for both the fragmentation of an asteroid at the time of impact and the subsequent gravitational interactions of the generated fragments. The simulations demonstrate that the catastrophic disruption of bodies larger than a few hundred meters in diameter leads to the formation of large aggregates due to gravitational reaccumulation of smaller fragments, which helps explain the presence of large members within asteroid families. Thus, for the first time, numerical simulations successfully reproduced the sizes and ejection velocities of members of representative families. Moreover, the simulations provide constraints on the family dynamical histories and on the possible internal structure of family members and their parent bodies.