Dynamical evolution of the WASP-19 star-planet system showing the orbital period versus the stellar spin period, in five different cases assuming values of the stellar tidal dissipation factor (see text) ranging from 10⁶ (2 cases) to 10⁹. The corresponding ages, in million years, are shown by the color scale to the right. The observational constraints are represented by a square. Only models with values of above 3 × 10⁷ are able to match the observations.