Influence of some resonances on the inclination of a satellite
- 1CIDMA, Department of Mathematics, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
- 2CFisUC, Department of Physics, University of Coimbra, Rua Larga, 3004-516 Coimbra, Portugal
- 3ASD, IMCCE, Observatoire de Paris, PSL Research University, CNRS UMR 8028, 77 Avenue Denfert-Rochereau, 75014 Paris, France
Knowing if the inclination of a satellite with respect to the equator of its planet is primordial can give hints on its origin and its formation. However, several mechanisms are able to modify its inclination during its evolution. The orbit of a satellite evolves over time and because of the tidal dissipation its semi-major axis can notably decrease or increase. Therefore the satellite can encounter several resonances in which it can potentially be captured. Some resonances are able to modify the equatorial inclination of a satellite. Touma and Wisdom (1998) noted that a resonance called ‘eviction’ between the mean motion of the Earth and the ascending node frequency of the Moon could increase by several degrees the equatorial inclination of the early Moon and could explain the present orientation of its orbit. Yokoyama (2002) studied these resonances for Phobos and Triton and observed that several resonances of this type can increase the equatorial inclination of Phobos in the future.
In this work, we study the different existing ‘eviction’ resonances to determine their possible influence on the equatorial inclination of a satellite. When a satellite goes through such a resonance, the capture is not certain and as noted by Yokoyama (2002), the probability of capture depends on several parameters as the obliquity of the planet and the interaction between other resonances. We consider the case of Phobos where we search to estimate the probability of a capture in an ‘eviction’ resonance by using an analytical Hamiltonian model and numerical simulations. This work will then notably estimate the probability that Phobos will be captured in the future in an ‘eviction’ resonance able to modify significantly its inclination and will measure the influence of the different parameters over the probability of capture.
Acknowledgments: The authors acknowledge support from project POCI-01-0145-FEDER-029932 (PTDC/FIS-AST/29932/2017), funded by FEDER through COMPETE 2020 (POCI) and FCT.
References:
Touma J. and Wisdom J., Resonances in the Early Evolution of the Earth-Moon System. The Astronomical Journal, 115:1653–1663, 1998.
Yokoyama T., Possible effects of secular resonances in Phobos and Triton. Planetary and Space Science, 50:63–77, 2002.
How to cite: Vaillant, T. and Correia, A. C. M.: Influence of some resonances on the inclination of a satellite, Europlanet Science Congress 2020, online, 21 September–9 Oct 2020, EPSC2020-440, https://doi.org/10.5194/epsc2020-440, 2020
