Zooming in on selected ridges of the FLI. In the left panel, we select a faint ridge to zoom in on, marked with an asterisk. Since the ridges are almost parallel to the ẋ axis, we can suitably represent their one-dimensional section by computing again the FLI on many more initial conditions close to the ridge, but having the same value of ẋ. The result of the one-dimensional FLI computation is represented in the right panel: zooming in on the ridge we better detect its amplitude, and initial conditions having deeper encounters. The integration time is |T| = 400 yrs.