Presentation #102.195 in the session Poster Session.
With equilibrium temperatures that exceed 2200K, Ultrahot Jupiters (UHJs) are the most extreme category of exoplanets; these gas giant planets orbit their host stars so closely that their orbits become tidally synchronous. This results in large temperature differences — sometimes greater than 1000 K — and spatial inhomogeneities between the irradiated dayside and cooler nightside. In this temperature regime, exotic processes such as magnetic drag begin to play a critical role in shaping the atmospheric structure. These extreme physical conditions require modeling in three dimensions in order to accurately depict the atmospheric state of the planet. Until my recent work, 3D GCMs have only applied magnetic drag uniformly around the planet, which is physically inconsistent, given that one would expect stronger magnetic effects on the much hotter dayside. I apply a locally calculated “active” magnetic drag prescription on a model of the UHJ WASP-76b and show this active drag alters the atmospheric flow pattern, particularly in the upper atmosphere. Additionally, I calculate how these changes in atmospheric structure manifest themselves in observables such as phase curves and high resolution emission spectroscopy. I also emphasize the critical need to model these planets in 3D and to account for magnetic effects—as not doing so can result in biased retrievals of Doppler shifts of high resolution emission spectra.