title: Chemical kinetics on extrasolar planets.
abstract: Chemical kinetics plays an important role in controlling the atmospheric composition of all planetary atmospheres, including those of extrasolar planets. For the hottest exoplanets, the composition can closely follow thermochemical-equilibrium predictions, at least in the visible and infrared photosphere at dayside (eclipse) conditions. However, for atmospheric temperatures approximately <2000K, and in the uppermost atmosphere at any temperature, chemical kinetics matters. The two key mechanisms by which kinetic processes drive an exoplanet atmosphere out of equilibrium are photochemistry and transport-induced quenching. I review these disequilibrium processes in detail, discuss observational consequences and examine some of the current evidence for kinetic processes on extrasolar planets.
authors.affiliation: Space Science Institute, 4750 Walnut Street, Suite 205, Boulder, CO 80301, USA.
authors.forename: Julianne I
authors.initials: JI
authors.lastname: Moses
keywords: atmospheric chemistry; chemical kinetics; exoplanets; extrasolar planets; photochemistry; planetary atmospheres