High-resolution atmospheric flow simulations of the tidally-locked extrasolar giant planet, HD209458b, show large-scale spatio-temporal variability. This is in contrast to the simple, permanent day/night (i.e., hot/cold) picture. The planet’s global circulation is characterized by a polar vortex in motion around each pole and a banded structure corresponding to ∼3 broad zonal (east-west) jets. ...
