Mercury's capture into the 3/2 spin-orbit resonance as a result of its chaotic dynamics

  title={Mercury's capture into the 3/2 spin-orbit resonance as a result of its chaotic dynamics},
  author={Alexandre C. M. Correia and Jacques Laskar},
Mercury is locked into a 3/2 spin-orbit resonance where it rotates three times on its axis for every two orbits around the sun. The stability of this equilibrium state is well established, but our understanding of how this state initially arose remains unsatisfactory. Unless one uses an unrealistic tidal model with constant torques (which cannot account for the observed damping of the libration of the planet) the computed probability of capture into 3/2 resonance is very low (about 7 per cent… 
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