Stability of circumbinary planets: The role of binary properties and migration scenarios
4 affiliations
- 1Univ. Grenoble Alpes, CNRS, IPAG
- 2Instituto de Astronomía Teórica y Experimental (IATE), UNC-CONICET
- 3Instituto de Astrofísica, Pontificia Universidad Católica de Chile
- 4School of Physics & Astronomy, University of Birmingham
Abstract
Context. Of the thousands of exoplanets detected to date, only a very small fraction are classified as circumbinary planets. When considering only low-mass planets, their number becomes negligible. This rarity may be partly explained by observational biases, but also by the challenging dynamical environment that often prevents the long-term stability of planetary orbits in binary systems. Aims. It is therefore essential to investigate the conditions that enable the formation and survival of stable circumbinary planets, with particular attention to the case of low-mass planets. Methods. To this end, we performed N-body simulations coupled with a planet migration prescription to study the post-formation dynamics of two circumbinary planets of 10 Earth masses in a protoplanetary disc. This approach allowed us to estimate whether, for a given set of binary and planetary parameters, planets remain bound to their stars or become unstable and ejected. Results. Based on more than 1000 simulations, our results indicate that two-planet inward migration can, in some cases, be halted through resonance capture with the binary. In contrast to some previous purely N-body studies, such configurations appear to remain stable over long timescales. We further find that the binary parameters qB and eB play a key role in shaping the stability landscape of multi-planet systems. Within the explored parameter space, some regions support long-term stability, whereas others appear highly unstable. These stability regions are also highly sensitive to the migration timescales (i.e. 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. Conclusions. This constitutes a first step towards identifying the most promising binary star systems likely to host multiple low-mass circumbinary planets. They may serve as valuable guidelines for future observational campaigns, such as those of PLATO and Gaia.
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
@article{romain2026stability,
title = {{Stability of circumbinary planets: The role of binary properties and migration scenarios}},
author = {Grane Romain and Cuello Nicolás and Sucerquia Mario and Gianuzzi Emmanuel and Ávila-Bravo Milenne and Charalambous Carolina and Triaud Amaury H. M. J.},
journal = {Astronomy \& Astrophysics},
year = {2026},
month = oct,
doi = {10.1051/0004-6361/202660738},
url = {https://doi.org/10.1051/0004-6361/202660738},
note = {CC BY},
}
RIS
TY - JOUR
TI - Stability of circumbinary planets: The role of binary properties and migration scenarios
AU - Grane Romain
AU - Cuello Nicolás
AU - Sucerquia Mario
AU - Gianuzzi Emmanuel
AU - Ávila-Bravo Milenne
AU - Charalambous Carolina
AU - Triaud Amaury H. M. J.
PY - 2026
DA - 2026/10/29
JO - Astronomy & Astrophysics
DO - 10.1051/0004-6361/202660738
UR - https://doi.org/10.1051/0004-6361/202660738
AB - Context. Of the thousands of exoplanets detected to date, only a very small fraction are classified as circumbinary planets. When considering only low-mass planets, their number becomes negligible. This rarity may be partly explained by observational biases, but also by the challenging dynamical environment that often prevents the long-term stability of planetary orbits in binary systems. Aims. It is therefore essential to investigate the conditions that enable the formation and survival of stable circumbinary planets, with particular attention to the case of low-mass planets. Methods. To this end, we performed N-body simulations coupled with a planet migration prescription to study the post-formation dynamics of two circumbinary planets of 10 Earth masses in a protoplanetary disc. This approach allowed us to estimate whether, for a given set of binary and planetary parameters, planets remain bound to their stars or become unstable and ejected. Results. Based on more than 1000 simulations, our results indicate that two-planet inward migration can, in some cases, be halted through resonance capture with the binary. In contrast to some previous purely N-body studies, such configurations appear to remain stable over long timescales. We further find that the binary parameters qB and eB play a key role in shaping the stability landscape of multi-planet systems. Within the explored parameter space, some regions support long-term stability, whereas others appear highly unstable. These stability regions are also highly sensitive to the migration timescales (i.e. 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. Conclusions. This constitutes a first step towards identifying the most promising binary star systems likely to host multiple low-mass circumbinary planets. They may serve as valuable guidelines for future observational campaigns, such as those of PLATO and Gaia.
SN - 0004-6361
SN - 1432-0746
ER -