.THE APPLICATION of Bayesian inversion to a series of lithologic parameters in an evaluation of seismic data hardly seems right stuff of titles. Yet when the seismic data you are actually analyzing arised from Mars, and when your reasoning suggests that the greatest illustration for them is actually liquid water in the pores in between rocks, you possess a tale. There is little people thirst for more, when it concerns wandering science, than water on Mars. Why carries out the prospect provoke such exhilaration-- and what performs this brand-new analysis contribute to the story?