Large-Scale Variations in the Obliquity of Mars

  title={Large-Scale Variations in the Obliquity of Mars},
  author={W. R. Ward},
  pages={260 - 262}
  • W. R. Ward
  • Published 20 July 1973
  • Physics, Geology
  • Science
Large-scale variations in the obliquity of the planet Mars are produced by a coupling between the motion of its orbit plane due to the gravitational perturbations of the other planets and the precession of its spin axis which results from the solar torque exerted on the equatorial bulge of the planet. The obliquity oscillates on a time scale of approximately 1.2 x 105 years. The amplitude of this oscillation itself varies periodically on a time scale of 1.2 X 106 years. The present-day… 

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