.THE app of Bayesian contradiction to a series of lithologic criteria in an assessment of seismic records rarely seems the stuff of headlines. But when the seismic records you are actually determining stemmed from Mars, and when your reasoning suggests that the best explanation for all of them is liquefied water in the pores in between rocks, you possess an account. There is little people crave much more, when it involves planetary science, than water on Mars. Why performs the possibility prompt such exhilaration-- and what performs this new analysis contribute to the account?