| Texto completo | |
| Autor(es): |
Barbosa, G. O.
;
Santana, T.
;
Winter, O. C.
Número total de Autores: 3
|
| Tipo de documento: | Artigo Científico |
| Fonte: | ICARUS; v. 448, p. 14-pg., 2026-04-01. |
| Resumo | |
We investigate the long-term dynamical stability of moons orbiting planets by performing high-resolution N-body simulations across five planet-to-star mass ratios (mu = 10(-1) to 10(-5)). Moons are modeled as massless test particles and their orbits are initialized at pericenter, where stellar perturbations are minimized. This setup yields upper-envelope estimates of the outermost stable semimajor axis (a(E)) under optimally phased initial conditions, which we systematically map as a function of eccentricity. We derive empirical fits for a(E)(e) in each mu regime and observe that the stable region contracts with increasing eccentricity and decreasing planetary mass. For larger values of mu, we identify a detached island of stability at intermediate eccentricities (0.2 less than or similar to e less than or similar to 0.7), which we show to be associated with the evection resonance; additional integrations confirm libration of the resonant angle. We examine the sensitivity of a(E) to the initial satellite-star mean-anomaly offset (4M) and find that orbital phase can modulate the critical stability threshold by less than or similar to 10%. Our updated stability criteria therefore consist of: (i) new empirical fits for the critical semimajor axis as a function of eccentricity, (ii) its systematic dependence on the planet-to-star mass ratio, and (iii) the role of the evection resonance and orbital phase in extending stability beyond classical limits. These results provide a refined framework for assessing exomoon survivability across diverse planetary systems. The empirical relations presented in this work can be directly employed to constrain the parameter space in observational searches for exomoons. (AU) | |
| Processo FAPESP: | 22/11783-5 - Evolução Orbital de Sistemas com Pequenos Corpos |
| Beneficiário: | Othon Cabo Winter |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |