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
Ascraeus Mons zone of knobby terrain outlined by a semicircular zone of concentric ridges. Similar deposits are also found at the northwestern edges of the other two Tharsis Montes, Pavonis Mons and Arsia Mons, as well as on Olympus Mons. The FSD at Ascraeus Mons is the smallest of those on the Tharsis Montes, covering an area of 14,000 km and extending outward from the volcano's base for about 100 km. The origin of these deposits has been debated for decades. However, recent geologic evidence suggests that FSDs are deposits left by glaciers, which covered portions of the volcanoes during a recent