True polar wander on Mars True polar wander on Mars For some time, scientists have thought that the location of the poles of Mars have shifted due to the great mass of volcanic material in the Tharsis dome which includes Olympus Mons, the highest volcano in the solar system. A study published in Nature supports this idea. For a period early in the history of Mars, the poles were about 20 degrees away from their present positions. At that time ice was deposited in a region called Dorsa Argentea Formation. Also, the Martian dichotomy was aligned along the equator. A band of rivers formed at
Olympus Mons - its flanks are shallower and extend farther from the summit in the northwestern direction than they do to the southeast. The volcano's shape and profile have been likened to a "circus tent" held up by a single pole that is shifted off center. Due to the size and shallow slopes of Olympus Mons, an observer standing on the Martian surface would be unable to view the entire profile of the volcano, even from a great distance. The curvature of the planet and the volcano itself would obscure such a synoptic view. Similarly, an observer near the summit would be