Simulations of fluid motion in spheroidal planetary cores driven by latitudinal libration

► Studies the fluid motion driven by latitudinal libration in ellipsoidal cavities. ► Nonlinear effects in viscous boundary layer produce a strong retrograde mean zonal flow. ► Reveals occurrence of strong resonance at some particular libration frequencies. ► Contrasts to no resonance of the fluid motion driven by longitudinal libration. ► Results may have significant implications for planetary dynamics and evolution.