On a ring origin of the equatorial ridge of Iapetus Options

[Guest_AlexBlackwell_*]

Wing Ip just had an interesting Iapetus-related paper published in GRL.

[tasp]

3 intersecting ridges, all describing segments of great circles about Iapetus.

Not to belabor the point, but there is not an internal geological process that gives a whit about great circles configured this way. The feature 'shouts' external orbital causation. Consider precession of the rotation axis of Iapetus (or inclined structures in orbit above), syncronization of the deposition process as the highest spot on the equator passes through the ring plane twice per rotation. The ground track per the relevant orientations of the ring, equator, highest spot along the equator, and precession (or inclined structure) is where the ring emplaces.

{Sorry for the crappy diagram}

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