liberte@uiucdcsb.cs.uiuc.edu (02/04/88)
Mars appears to have had crust shifting activity. A Scientific American article about two years ago described at least three independent pieces of evidence that the polar ice caps moved to the equator several million years ago. The one I liked was the butterfly patterns attributed to meteor impacts that tend to align with the equator. There are predominently two sets of these patterns, one aligned with the current equator and the other aligned with what would have been the equator before the polar shift. Dan LaLiberte liberte@a.cs.uiuc.edu uiucdcs!liberte