Isn there lots of evidence for Water on Mars?
That depends on how you interpret it. There is also lots of evidence against water on Mars. The present day surface and soil is extremely dry and there is very little water in the polar caps. Analysis of the SNC meteorites also shows that they are very dry compared to equivalent Earth rocks. In the end, the only strong argument for water on Mars (other than during the main bombardment, when conditions were obviously very different) are the Outburst “flood” channels. Unfortunately, it gets very difficult to explain how repeated huge outbursts of water can occur on a planet with essentially no water recycling processes in its atmosphere. If we could find a way to explain the “floods” without using liquid water, then all the paradoxes of Mars disappear.
