Example of simulation using the fully coupled secular model. Black and blue are used for quantities related to the planet’s spin axis and satellite’s orbit, respectively. The orbital elements of the satellite are measured with respect to the equator and equinox of date (we indicate this reference frame by the index Q). In this example, the secular spin-orbit resonance angle is σ₂ = ψ + ϕ₂. The mass of the satellite is m/M = 2.2 × 10⁻³; it is initialised close to the local Laplace equilibrium at a = 37 R_eq and made migrating outwards with timescale τ = 6.5 Gyr.