.THE APPLICATION of Bayesian contradiction to a stable of lithologic criteria in an analysis of seismic data rarely appears the stuff of headlines. Yet when the seismic records you are actually determining originated from Mars, and when your reasoning proposes that the best illustration for all of them is actually liquid water in the pores between rocks, you possess an account. There is dwarfs thirst for much more, when it concerns global scientific research, than water on Mars. Why does the prospect produce such pleasure-- as well as what performs this brand new analysis include in the story?