be multiplied by a factor 5 to 7.5, as Io might have been trapped in a low order commensurability with Europa and Ganymede during part of its evolution, slowing down the expansion of its orbit. This roughly yields $$k_\mathrm{J}\Delta t_\mathrm{J}\lesssim2-3\times 10^{-2}\,\mathrm{s}.$$

For sake of easy comparison, we will refer to the quantity $Q'_0$, which is the reduced quality factor computed for a reference period of 1 day: $$Q'_0=\frac{3}{2}\frac{Q(2\pi/1\,\mathrm{day})}{k_2}=\frac{3}{2}\frac{1\,\mathrm{day}}{2\pi\, k_2 \Delta t}.$$ The above calculated constraint reads $Q'_{0,\mathrm{p}}\gtrsim 1\times10^6$. In the present calculations, we will examine two cases for the planet under consideration, namely $Q'_{0,\mathrm{p}}=10^6$ and $Q'_{0,\mathrm{p}}=10^7$ ($\kp\dtp\sim2\times10^{-2}-2\times10^{-3}$), while taking $Q'_{0,\star}$ in the range $10^5-10^6$ ($\ks\dts\sim2\times10^{-1}-2\times10^{-2}$), a typical value for solar-type stars [@OL07].

It is important to stress that, if $\Delta t$, or its counterpart $Q$, is poorly known for both planets and stars, its variability from one object or configuration to another is even more uncertain. For instance, tidal dissipation in planets probably differs significantly from the one in brown dwarfs because of the presence of a dense core able to excite inertial waves in the convective envelope [@GL09]. Given the highly non-linear behavior of tidal dissipation mechanisms, the effective tidal dissipation function varies not only with the structure of 