The tidal-thermal evolution of the Pluto-Charon system - Archive ouverte HAL Access content directly
Journal Articles Icarus Year : 2022

The tidal-thermal evolution of the Pluto-Charon system

, , , (1) , ,
1
Amirhossein Bagherian
  • Function : Author
Amir Khan
Frédéric Deschamps
  • Function : Author
Henri Samuel
Mikhail Kruglyakov
  • Function : Author
Domenico Giardini

Abstract

The existence of subsurface oceans on the satellites of the giant planets and Trans-Neptunian objects has been predicted for some time. Liquid oceans on icy worlds, if present, exert a considerable influence on the dynamics of the ice-ocean system and, because of the astrobiological potential, represent an important objective for future missions to the outer solar system. The Pluto-Charon system is representative of an icy moon orbiting a dwarf planet that is believed to have formed from the remnants of a giant impact. The evolution of icy moons is primarily controlled by the mode and efficiency of heat transfer through the outer ice shell, which is influenced by the presence of impurities, by tidal dissipation in the ice shell, and by the radioactive element budget in the silicate core. Previous studies on the evolution of the Pluto-Charon system generally considered either only the thermal or the tidal evolution, and in the cases where both were considered, the important effect of the presence of impurities in the liquid oceans was not addressed. Here, we consider the joint tidal-thermal evolution of the Pluto-Charon system by combining a comprehensive tidal model that incorporates a viscoelastic description of the tidal response with a parameterized thermal convection model developed for icy worlds. This approach enables an extensive analysis of the conditions required for the formation and maintenance of subsurface liquid oceans up to the present. Our results show that because of relatively fast circularization and synchronization of the orbits of Pluto and Charon, tidal heating is only important during the early stages of evolution (<1 Myr). As part of our study, we test the sensitivity of our results to a number of parameters that pertain to the orbital and thermal history. In all the studied cases, oceans on Pluto are always predicted to remain liquid to the present, ranging in thickness from 40 km to 150-km, whereas oceans on Charon, while in-place for approximately 4 Gyr, have solidified. This is supported by New Horizons observations of primarily extensional faults on Pluto and both extensional and compressional faults on Charon.
Fichier principal
Vignette du fichier
1-s2.0-S001910352100508X-main.pdf (1.57 Mo) Télécharger le fichier
Origin : Publisher files allowed on an open archive

Dates and versions

insu-03643024 , version 1 (20-04-2022)

Licence

Attribution - CC BY 4.0

Identifiers

Cite

Amirhossein Bagherian, Amir Khan, Frédéric Deschamps, Henri Samuel, Mikhail Kruglyakov, et al.. The tidal-thermal evolution of the Pluto-Charon system. Icarus, 2022, 376, ⟨10.1016/j.icarus.2021.114871⟩. ⟨insu-03643024⟩
22 View
7 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More