Delayed formation of the equatorial ridge on Iapetus from a subsatellite created in a giant impact

  title={Delayed formation of the equatorial ridge on Iapetus from a subsatellite created in a giant impact},
  author={Andrew J. Dombard and Andrew Cheng and William B. McKinnon and Jonathan P. Kay},
  journal={Journal of Geophysical Research},
[1] The great equatorial ridge on Saturn's moon Iapetus is arguably the most perplexing landform in the solar system. The ridge is a mountain range up to 20 km tall and sitting on the equator of Iapetus, and explaining its creation is an unresolved challenge. Models of its formation must satisfy three critical observations: why the ridge (1) sits exactly on the equator, (2) is found only on the equator, and (3) is thus far found only on Iapetus. We argue that all previously proposed models fail… Expand

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