Mars: Not as dry as it seems

Image shows modern Mars (left) dry and barren, compared with the same scene over 3.5 billion years ago covered in water (right). The rocks of the surface were slowly reacting with the water, sequestering it into the Martian mantle leading to the dry, inhospitable scene shown on the left. Image credit: Jon Wade When searching for life, scientists first look for an element key to sustaining it: fresh water. Although today's Martian surface is barren, frozen and inhabitable, a trail of evidence points to a once warmer, wetter planet, where water flowed freely. The conundrum of what happened to this water is long standing and unsolved. However, new research published in Nature suggests that this water is now locked in the Martian rocks. Scientists at Oxford's Department of Earth Sciences, propose that the Martian surface reacted with the water and then absorbed it, increasing the rocks oxidation in the process, making the planet uninhabitable.