Constraining the orbit of the retrograde planet in the ν Octantis system
Abstract
The ν Octantis system is composed of a compact stellar binary and a retrograde S-type planet orbiting near the edge of stability. Here, we investigate the dynamically viable architectures of this system by exploring the planetary orbital elements with a Monte Carlo method. To handle the large number of free parameters, we employed a novel approach in which all relevant orbital parameters were varied simultaneously, which we refer to as corner stability maps. Furthermore, since the osculating orbital period of the planet undergoes large oscillations, we combined these maps with frequency analysis to identify the stable configurations that remain consistent with the observational data. We find that the retrograde planetary orbit most likely lies in the region of influence of the high-order 28/−11 mean-motion resonance, where its long-term stability is enhanced by secular apsidal alignment.
Versions
Related
- A retrodictive theory of the origin of the Moon: a secondary circumterrestrial disk redistributed by the retrograde flyby of a rocky planet
- Revisiting the Photometric Modulation Amplitudes of Kepler Planet Hosts: A Confounder-Adjusted Test of Stellar Spin-Orbit Alignment
- ATREIDES II. Detection of a polar orbit for HAT-P-26 b, a fluffy planet in the Neptunian ridge
- The GAPS Programme at TNG. LXXX. Characterisation of the 400 Myr old multi-planet system K2-233
- Gas-depleted planet formation occurred in the four-planet system around the red dwarf LHS 1903
BibTeX
@misc{signor2026constraining,
title = {{Constraining the orbit of the retrograde planet in the $ν$ Octantis system}},
author = {Alan Cefali Signor and Alexandre C. M. Correia and Maria Helena Moreira Morais and Timothée Vaillant and Ho Wan Cheng and Man Hoi Lee and Trifon Trifonov},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.06885},
eprint = {2609.06885},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.06885},
}
RIS
TY - UNPB
TI - Constraining the orbit of the retrograde planet in the ν Octantis system
AU - Alan Cefali Signor
AU - Alexandre C. M. Correia
AU - Maria Helena Moreira Morais
AU - Timothée Vaillant
AU - Ho Wan Cheng
AU - Man Hoi Lee
AU - Trifon Trifonov
PY - 2026
DA - 2026/09/07
PB - arXiv
DO - 10.48550/arxiv.2609.06885
UR - https://arxiv.org/abs/2609.06885
AB - The ν Octantis system is composed of a compact stellar binary and a retrograde S-type planet orbiting near the edge of stability. Here, we investigate the dynamically viable architectures of this system by exploring the planetary orbital elements with a Monte Carlo method. To handle the large number of free parameters, we employed a novel approach in which all relevant orbital parameters were varied simultaneously, which we refer to as corner stability maps. Furthermore, since the osculating orbital period of the planet undergoes large oscillations, we combined these maps with frequency analysis to identify the stable configurations that remain consistent with the observational data. We find that the retrograde planetary orbit most likely lies in the region of influence of the high-order 28/−11 mean-motion resonance, where its long-term stability is enhanced by secular apsidal alignment.
ER -