The confinement of Neptune's ring arcs by the moon Galatea

  title={The confinement of Neptune's ring arcs by the moon Galatea},
  author={F Namouni and Carolyn C. Porco},
Neptune has five narrow ring arcs, spanning about 40 degrees in longitude, which are apparently confined against the rapid azimuthal and radial spreading that normally results from inter-particle collisions. A gravitational resonance based on the vertical motion of the nearby neptunian moon Galatea was proposed to explain the trapping of the ring particles into a sequence of arcs. But recent observations have indicated that the arcs are away from the resonance, leaving their stability again… 
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