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For the $5:3$ exterior mean-motion resonance, $p=3$, $q=2$. The truncated dissipative resonant eccentricity equilibrium givesFor weak drag and $C>0$, take the resonant-argument libration centre ${\varphi }_0\simeq \pi$. The pericentre geometry of an exterior resonance then places the three pericentres at angles $\pi /3$, $\pi$, and $5\pi /3$ relative to the planet. The trajectory closes after three particle orbits and five planet orbits. It moves retrograde in the rotating frame on average but develops a prograde loop near each periapsis, because the periapsis angular speed exceeds the planet's angular speed.

For a finite drag offset ${\varphi }_0=\pi +\arcsin S$, rotate the whole particle pattern through $\arcsin S/3$. The sketch uses the eccentricity requested by the second-order model; $e\simeq 0.555$ is not small, so the curve is an illustration of that approximation rather than a quantitatively accurate integration of the full dissipative resonance.

At periapsis, the particle's mean longitude equals its longitude of periapsis: $\lambda =\varpi$. Hence the pericentre geometry of an exterior resonance givesThe resonant argument therefore fixes the angular separation from the planet whenever the particle reaches periapsis. With $r_{\mathrm{peri}}=a(1-e)$ and planetary radius $a_p$, the actual separation isThus a restricted libration phase can prevent close encounters even when the radial ranges of the two orbits overlap: this is resonance protection.