.THE function of Bayesian inversion to a range of lithologic specifications in an evaluation of seismic records rarely seems to be right stuff of headlines. However when the seismic information you are actually analyzing originated from Mars, and when your reasoning proposes that the best description for all of them is actually liquid water in the pores in between stones, you possess a story. There is actually little people thirst for extra, when it concerns global science, than water on Mars. Why does the possibility produce such enjoyment-- and what does this new analysis add to the story?