We know there is water on Mars in the cryosphere...
On August 5 this past summer, the NASA land rover Curiosity reached Mars. Part of its mission is to search for signs of water (either past or present). We know there is water on Mars in the cryosphere (permafrost and polar caps). It is suspected that there were large bodies of water in ages past forming a hydrosphere in which life may have emerged. Water is vital for life as we know it. It is also important for fun and games. This past summer, water was the venue of so many of the Olympic sports: diving, swimming, polo, rowing.