|This map shows an excellent match between the geological structure of the Tharsis region on present-day Mars (left), where glaciers remnants are indicated in yellow, and a simulation of glacier formation by atmospheric precipitation in the same region a few millions year ago (right).
In the simulation, performed by a Martian climate computer modelling tool, it is assumed that the rotation axis of the planet was tilted by 45Âº with respect to the planet´ orbital plane, about 20Âº more than today. Here, the results of the simulation are superimposed on a topographical map of the Tharsis area made by NASA's Mars Global Surveyor MOLA altimeter.
Credits: A: D.H. Scott, K.L. Tanaka, USGS. B: Lab. de Meteorologie Dynamic, IPSL (Paris, France)/MGS MOLA