Unsteady flows in Io's atmosphere caused by condensation and sublimation during and after eclipse: Numerical study based on a model Boltzmann equation

► Time evolution of the profiles of the physical quantities is obtained in detail. ► An oscillatory motion of the atmosphere during eclipse is revealed. ► The oscillation in a pure SO2 atmosphere is strong but decays rapidly. ► The oscillation in the presence of a noncondensable gas is weak but lasts longer. ► A noncondensable gas impedes the atmospheric collapse during eclipse efficiently.