Chaotic Excitation and Tidal Damping in the GJ 876 System

  title={Chaotic Excitation and Tidal Damping in the GJ 876 System},
  author={Abhijit Puranam and Konstantin Batygin},
  journal={The Astronomical Journal},
The M-dwarf GJ 876 is the closest known star to harbor a multi-planetary system. With three outer planets locked in a chaotic Laplace-type resonance and an appreciably eccentric short-period super-Earth, this system represents a unique exposition of extrasolar planetary dynamics. A key question that concerns the long-term evolution of this system, and the fate of close-in planets in general, is how the significant eccentricity of the inner-most planet is maintained against tidal circularization… 

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