It is a growing and popular belief in scientific cirles that the photographic and mineral evidence obtained by recent space probes points with a fair degree of certainty to the existence of running water in the distant Martian past. Gwendolyn Bart, a graduate student in planetary sciences at the University of Arizona has another idea, that perhaps the features can be explained by processes other than water. Bart and other scientists feel that Mars’ temperature and pressure are so low that liquid water could not have formed. Landslides and the flow of dust could just as easily explain the grooves and channels seen on the surface. More on this intriguing idea, (though personally I favour water) can be found at space.com.