Secular normalized torques of zero-order |⟨T⁰(r₂)⟩| (left column) and first-order |⟨T¹(r₂)⟩| (right column), computed on m₂ due to the tidal deformation on m₀ induced by m₁, plotted as a function of the mean-motion ratio n₁ ∕ n₂. We considered m₀ = 1, a₁ = 1 and varied a₂ to include orbits both interior and exterior to m₁. Upper panels: circular orbits (e₁ = e₂ = 0). Lower panels: eccentric orbits with e₁ = e₂ = 0.1. Light brown vertical lines highlight the location of some important MMRs. We note that the first-order torques in the right panels are also normalized respect to the time-lag Δt₀.