School of Mathematical Sciences
Published online: 16 February 2011
The equilibrium tide model in the weak friction approximation is used by the binary star and exoplanet communities to study the tidal evolution of short-period systems. However, each uses a slightly diﬀerent approach which potentially leads to diﬀerent conclusions about the timescales on which various processes occur. Here we present an overview of these two approaches, and show that for short-period planets the circularization timescales they predict diﬀer by at most a factor of a few. A discussion of the timescales for orbital decay, spin-orbit synchronization and spin-oribt alignment is also presented.
© Owned by the authors, published by EDP Sciences, 2011