Exomoons of Circumbinary Planets

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Gordon, Ben R, Buschermöhle, Helena, Tubthong, Wata, Martin, David V., Smallets, Sean, Masiello, Grace, Bergeron, Liz
Format: Preprint
Veröffentlicht: 2024
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866917017336938496
author Gordon, Ben R
Buschermöhle, Helena
Tubthong, Wata
Martin, David V.
Smallets, Sean
Masiello, Grace
Bergeron, Liz
author_facet Gordon, Ben R
Buschermöhle, Helena
Tubthong, Wata
Martin, David V.
Smallets, Sean
Masiello, Grace
Bergeron, Liz
contents Confirmation of the first exomoon remains elusive. Although several exomoon candidates exist around single stars, there are currently no candidates around circumbinary planets (CBPs). Most circumbinary planets are thought to form far from the host binary and migrate through the protoplanetary disc. Therefore, an exomoon of a CBP represents a fascinating yet complex and evolving four-body system. Their existence (or absence) would shed light on the robustness of moon formation and evolution in dynamically active planetary systems. In this work, we simulate the orbital evolutions of exomoons around migrating CBPs. We show that for fully migrated CBPs, a moon is capable of surviving the migration if it is formed within $\sim5-10\%$ of the planet's Hill Radius, well within the currently proposed range at which moons are thought to settle in the planetary disc for giant planets. Even though all known CBPs are gas giants, 18\% of the surviving moons in our sample are within the habitable zone, giving credence to circumbinary habitability, albeit hosted by moons rather than planets. $38\%$ of moons escape their host planet early in the migration and become long-period CBPs (i.e a multi-planet circumbinary system). Nearly one-third of exomoons collide with their host planet, and $1\%$ are ejected from the system entirely. This last class presents another pathway for producing free-floating planetary mass objects, like those discovered recently and expected from the Roman microlensing survey.
format Preprint
id arxiv_https___arxiv_org_abs_2412_02847
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Exomoons of Circumbinary Planets
Gordon, Ben R
Buschermöhle, Helena
Tubthong, Wata
Martin, David V.
Smallets, Sean
Masiello, Grace
Bergeron, Liz
Earth and Planetary Astrophysics
Confirmation of the first exomoon remains elusive. Although several exomoon candidates exist around single stars, there are currently no candidates around circumbinary planets (CBPs). Most circumbinary planets are thought to form far from the host binary and migrate through the protoplanetary disc. Therefore, an exomoon of a CBP represents a fascinating yet complex and evolving four-body system. Their existence (or absence) would shed light on the robustness of moon formation and evolution in dynamically active planetary systems. In this work, we simulate the orbital evolutions of exomoons around migrating CBPs. We show that for fully migrated CBPs, a moon is capable of surviving the migration if it is formed within $\sim5-10\%$ of the planet's Hill Radius, well within the currently proposed range at which moons are thought to settle in the planetary disc for giant planets. Even though all known CBPs are gas giants, 18\% of the surviving moons in our sample are within the habitable zone, giving credence to circumbinary habitability, albeit hosted by moons rather than planets. $38\%$ of moons escape their host planet early in the migration and become long-period CBPs (i.e a multi-planet circumbinary system). Nearly one-third of exomoons collide with their host planet, and $1\%$ are ejected from the system entirely. This last class presents another pathway for producing free-floating planetary mass objects, like those discovered recently and expected from the Roman microlensing survey.
title Exomoons of Circumbinary Planets
topic Earth and Planetary Astrophysics
url https://arxiv.org/abs/2412.02847