We present the results of simulations showing that the formation of stable arcs in narrow rings perturbed by a single eccentric perturber is to be expected. We have been performing simulations of a system resembling Saturn's F ring with a Prometheus like perturber. The ring is circular, but the moon is on an eccentric orbit. We find that in some of these simulations the ring material begins to group in azimuthally confined regions that resemble arcs. This type of behavior had been seen by Showalter and Burns (Icarus 1982 ...
