2005/02/28 by Curtis S. Cooper, Adam P. Showman · 4 citations
Physics and Astronomy · #Astro and Planetary Science #Astrophysics and Star Formation Studies #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/444354
published as Astrophys.J. 629 (2005) L45-L48 · Accepted by ApJ Letters
arxiv created 2005/06/28 · openalex publication_date 2005/07/18 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
We calculate the meteorology of the close-in transiting extrasolar planet HD 209458b using a global, three-dimensional atmospheric circulation model. Dynamics are driven by perpetual irradiation of one hemisphere of this tidally locked planet. The simulation predicts global temperature contrasts of ~500 K at the photosphere and the development of a steady superrotating jet. The jet extends from the equator to midlatitudes and from the top model layer at 1 mbar down to 10 bar at the base of the heated region. Wind velocities near the equator exceed 4 km s -1 at 300 mbar. The hottest regions of the atmosphere are blown downstream from the substellar point by ~60° of longitude. We predict from these results a factor of ~2 ratio between the maximum and minimum observed radiation from the planet over a full orbital period, with peak infrared emission preceding the time of the secondary eclipse by ~14 hr.