# Formation of Exomoons: A Solar System Perspective

## TL;DR

This paper reviews how moons form in our Solar System and explores how these theories can be applied to predict the sizes and formation mechanisms of potential exomoons around extrasolar planets, considering current detection capabilities.

## Contribution

It synthesizes recent ideas on moon formation and discusses their applicability to exoplanet systems, highlighting potential formation processes for detectable exomoons.

## Key findings

- Planet-planet collisions can produce large moons around rocky or icy planets.
- Co-accretion and capture are plausible formation mechanisms for exomoons around gas giants.
- Estimating maximum moon sizes around gas giants requires advanced simulations.

## Abstract

Satellite formation is a natural by-product of planet formation. With the discovery of nu- merous extrasolar planets, it is likely that moons of extrasolar planets (exomoons) will soon be discovered. Some of the most promising techniques can yield both the mass and radius of the moon. Here, I review recent ideas about the formation of moons in our Solar System, and discuss the prospects of extrapolating these theories to predict the sizes of moons that may be discovered around extrasolar planets. It seems likely that planet-planet collisions could create satellites around rocky or icy planets which are large enough to be detected by currently available techniques. Detectable exomoons around gas giants may be able to form by co-accretion or capture, but determining the upper limit on likely moon masses at gas giant planets requires more detailed, modern simulations of these processes.