Elastic ice shells of synchronous moons: Implications for cracks on Europa and non-synchronous rotation of Titan

  title={Elastic ice shells of synchronous moons: Implications for cracks on Europa and non-synchronous rotation of Titan},
  author={Peter Goldreich and Jonathan L. Mitchell},
A number of synchronous moons are thought to harbor water oceans beneath their outer ice shells. A subsurface ocean frictionally decouples the shell from the interior. This has led to proposals that a weak tidal or atmospheric torque might cause the shell to rotate differentially with respect to the synchronously rotating interior. Applications along these lines have been made to Europa and Titan. However, the shell is coupled to the ocean by an elastic torque. As a result of centrifugal and… 

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