Scientists from the University of Oxford argue that water is still on Mars, but it has been absorbed by rocks under the surface.
The enduring question about the Red Planet has always centered around the water, and where it all went. A new study by scientists at Oxford suggest that the water hasn’t gone far at all, a revolutionary finding that could change our approach to colonizing Mars in the coming decades.
Scientists believe that water flowed freely on Mars some three billion yearse ago, and that the planet was covered by oceans. Researchers aren’t quite sure how much water Mars may have had, but one thing that did baffle them is their inability to explain where all the water went.
Proposals have included solar winds which drew the water into space after the Red Planet’s magnetic shield collapsed. Others claimed that it may exist in the form of subsurface ice deep below the Martian surface. But the team from Oxford believes that, based on an analysis of the chemistry of the planet, the water is being held within the planet’s rocks, which have merged with the mantle.
Dr Jon Wade, NERC Research Fellow in Oxford’s Department of Earth Sciences, said in a statement: ‘People have thought about this question for a long time, but never tested the theory of the water being absorbed as a result of simple rock reactions. There are pockets of evidence that together, leads us to believe that a different reaction is needed to oxidise the Martian mantle. For instance, Martian meteorites are chemically reduced compared to the surface rocks, and compositionally look very different. One reason for this, and why Mars lost all of its water, could be in its minerology.
‘The Earth’s current system of plate tectonics prevents drastic changes in surface water levels, with wet rocks efficiently dehydrating before they enter the Earth’s relatively dry mantle. But neither early Earth nor Mars had this system of recycling water. On Mars, (water reacting with the freshly erupted lavas’ that form its basaltic crust, resulted in a sponge-like effect. The planet’s water then reacted with the rocks to form a variety of water bearing minerals. This water-rock reaction changed the rock mineralogy and caused the planetary surface to dry and become inhospitable to life.’