Stability of Neptune's ring arcs in question

  title={Stability of Neptune's ring arcs in question},
  author={Christophe Dumas and Richard Terrile and Bradford A. Smith and Glenn Schneider and Eric Edward Becklin},
Although all four of the gas-giant planets in the Solar System have ring systems, only Neptune exhibits ‘ring arcs’—stable clumps of dust that are discontinuous from each other. Two basic mechanisms for confining the dust to these arcs have been proposed. The firstrelies on orbital resonances with two shepherding satellites, while the second invokes a single satellite (later suggested to be Galatea) to produce the observed ring arc structures. Here we report observations of the ring arcs and… 
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