More than three billion years ago, the surface of Mars underwent a drastic change. According to a recent model, built by the combined efforts of geophysicists and climatologists and described in Bouley et al., the change was triggered by the formation of the massive Tharsis volcanic plateau. A great elevated dome that accounts for nearly a quarter of the Martian surface and home to three of the largest volcanoes in the solar system, the Tharsis region is so massive that it initiated a complete shift in the outer skin of the planet upon its creation, with the crust and upper mantle swiveling about the core, like if the skin and underlying flesh of an avocado somehow rotated about the seed. The scientists came to this conclusion by modeling the Martian surface without the presence of Tharsis and found that the distribution of observed traces of ancient rivers and glaciers are much more consistent with a pre-Tharsis Mars, suggesting they formed during this pre-Tharsis time when the surface looked very different. Since Tharsis is such a major feature, likely impacting much of the climate through its volcanic activity and topography, this new development has major implications for our understanding of the evolution of Mars's climate - including, perhaps, implications for the possibility of life on its ancient surface.
- Sean Faulk
Staff Writer, Signal to Noise Magazine
PhD Candidate, Earth, Planetary, and Space Sciences
Bouley S, Baratoux B, Matsuyama I, Forget F, Séjourné A, Turbet M, Costard F. Late Tharsis formation and implications for early Mars. Nature. (2016). DOI: 10.1038/nature17171