Tidal flows in extrasolar planets
Orateur : Adrian Barker
DAMTP, University of Cambridge
Résumé : Over 1000 planets have been discovered orbiting stars other than the Sun. Many of these orbit their stars very closely, with orbital periods as short as one Earth day. Observations indicate that the tidal gravitational interaction between a close-in planet and its host star can have important effects on the planetary orbit. In particular, it is thought that the dissipation of tidally excited flows inside short-period planets can explain why their orbits tend to be circular, in comparison to those that orbit more distantly, which have a wide range of orbital eccentricities. I will first introduce the subject area, before presenting recent work on the nonlinear evolution of tidally excited flows in rotating planets, which aims to understand the mechanisms of tidal dissipation, and ultimately to explain these astrophysical observations. In the process, I will present the results of local and global simulations of the nonlinear evolution of the elliptical instability, as well as the nonlinear evolution of tidally excited inertial waves in a planet with an inner core.
Date et lieu : le Mercredi 18 Mars à 11h00, salle de séminaires IRPHE