Stability of circumbinary planets: the role of binary properties and migration scenarios
Abstract
Among the thousands of exoplanets detected to date, only a very small fraction are classified as circumbinary planets, and this number becomes negligible when considering low-mass planets. This rarity may partly result from observational biases, but also from the challenging dynamical environment of binary systems, which can prevent the long-term stability of planetary orbits. It is therefore essential to investigate the conditions that enable the formation and survival of stable circumbinary planets, particularly in the low-mass regime. To this end, we performed N-body simulations coupled with a planet migration prescription to study the post-formation dynamics of two 10 Earth-mass circumbinary planets in a protoplanetary disc. Based on more than 1,000 simulations, we find that inward migration can, in some cases, be halted through resonance capture with the binary. In contrast to some previous purely N-body studies, these configurations appear to remain stable over long timescales. We further find that the binary mass ratio qB and eccentricity eB strongly influence the stability of multi-planet systems. Within the explored parameter space, some regions support long-term stability, whereas others are highly unstable. These stability regions are also sensitive to the migration timescales, and therefore to disc properties and planetary masses. Finally, our simulations suggest that systems in which two planets enter resonance while migrating together are more likely to form stable multi-planet configurations, particularly around highly eccentric binaries. These results provide a first step toward identifying binary star systems that are most promising for hosting multiple low-mass circumbinary planets.
Related
- The Occurrence of Circumbinary Planets Around TESS M-dwarf Eclipsing Binaries
- Circumbinary planets in coplanar triple-star systems: I. Minimum eccentricity variation region
- Beyond static torques: Self-consistent migration and dynamical trapping of low-mass planets in dusty disks
- Double White Dwarfs with Circumbinary Disks: Evolution, Population Properties, and Gravitational Wave Signatures
- Migration and Evolution of giant ExoPlanets (MEEP). III. Twenty-Nine Giant Planets from the TESS Mission
BibTeX
@misc{grane2026stability,
title = {{Stability of circumbinary planets: the role of binary properties and migration scenarios}},
author = {Romain Grane and Nicolás Cuello and Mario Sucerquia and Emmanuel Gianuzzi and Milenne Ávila-Bravo and Carolina Charalambous and Amaury H. M. J. Triaud},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.05134},
eprint = {2609.05134},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.05134},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Stability of circumbinary planets: the role of binary properties and migration scenarios
AU - Romain Grane
AU - Nicolás Cuello
AU - Mario Sucerquia
AU - Emmanuel Gianuzzi
AU - Milenne Ávila-Bravo
AU - Carolina Charalambous
AU - Amaury H. M. J. Triaud
PY - 2026
DA - 2026/09/04
PB - arXiv
DO - 10.48550/arxiv.2609.05134
UR - https://arxiv.org/abs/2609.05134
AB - Among the thousands of exoplanets detected to date, only a very small fraction are classified as circumbinary planets, and this number becomes negligible when considering low-mass planets. This rarity may partly result from observational biases, but also from the challenging dynamical environment of binary systems, which can prevent the long-term stability of planetary orbits. It is therefore essential to investigate the conditions that enable the formation and survival of stable circumbinary planets, particularly in the low-mass regime. To this end, we performed N-body simulations coupled with a planet migration prescription to study the post-formation dynamics of two 10 Earth-mass circumbinary planets in a protoplanetary disc. Based on more than 1,000 simulations, we find that inward migration can, in some cases, be halted through resonance capture with the binary. In contrast to some previous purely N-body studies, these configurations appear to remain stable over long timescales. We further find that the binary mass ratio q_B and eccentricity e_B strongly influence the stability of multi-planet systems. Within the explored parameter space, some regions support long-term stability, whereas others are highly unstable. These stability regions are also sensitive to the migration timescales, and therefore to disc properties and planetary masses. Finally, our simulations suggest that systems in which two planets enter resonance while migrating together are more likely to form stable multi-planet configurations, particularly around highly eccentric binaries. These results provide a first step toward identifying binary star systems that are most promising for hosting multiple low-mass circumbinary planets.
ER -