2017/03/22 by François Soubiran, Burkhard Militzer, Kevin P. Driver +1 · 1 citation
Earth and Planetary Sciences · Physics and Astronomy · #Astro and Planetary Science #Convection #Diffusion #Gas giant #Giant planet #Helium #High-pressure geophysics and materials #Hydrogen #Planet #Planetary Science and Exploration #Silicon #Viscosity #astro-ph.EP
paper · pdf · doi:10.1063/1.4978618
published as Physics of Plasmas 24, 041401 (2017) · HEDLA 2016 Proceedings, Special issue of Physics of Plasmas. 7 pages, 8 figures
openalex publication_date 2017/03/22 · arxiv created 2017/03/28 · arxiv updated 2017/03/30 · openalex created_date 2017/04/07 · openalex updated_date 2026/08/06
Recent observations of Jupiter and Saturn provided by spacecraft missions, such as Juno and Cassini, compel us to revise and improve our models of giant planet interiors. Even though hydrogen and helium are by far the dominant species in these planets, heavy elements can play a significant role in the structure and evolution of the planet. For instance, giant-planet cores may be eroded by their surrounding fluid, which would result in a significantly increased concentration of heavy elements in the hydrogen-helium envelope. Furthermore, the heavy elements could inhibit convection by creating a stabilizing gradient of composition. In order to explore the effects of core erosion, we performed ab initio simulations to study structural, diffusion, and viscosity properties of dense multicomponent mixtures of hydrogen, helium, and silicon dioxide at relevant pressure-temperature conditions. We computed radial distribution functions to identify changes in the chemical behavior of the mixture and to reveal dissociation trends with pressure and temperature. The computed diffusion coefficients of the different species as well as the viscosity provide constraints for the time scale of the dynamics of the core erosion and the mixing of its constituents into the envelope, which will help improve planetary models.