Vol. 540
In section 10. Planets and planetary systems

A new vision of giant planet interiors: Impact of double diffusive convection

by J. Leconte and G. Chabrier, A&A 540, A20


Giant planets such as Jupiter and Saturn have long been thought of as fully convective, and as a result, their interior temperature would follow an adiabat. However, the presence of a core and, generally, of denser material at the bottom tends to oppose convection and lead to so-called double-diffusive convection. Leconte & Chabrier explore how results recently obtained from hydrodynamics change the picture and may lead to defining a new interior structure for both Jupiter and Saturn. They show that if layers due to double-diffusive convection are present throughout the hydrogen-helium envelopes of these planets, they should be significantly hotter at the center (by up to a factor 2 to 3) and contain more heavy elements than usually assumed.