Massive floods on Mars

Today, it’s pretty dry on the Red Planet. But that wasn’t always the case – quite the opposite, as researchers at the University of Texas at Austin can see from the way rivers and lakes have changed. On Earth, erosion by rivers is usually a slow process. On Mars, however, massive floods from overflowing crater lakes played a preeminent role in shaping the Martian surface, scouring out deep chasms and moving huge amounts of sediment.

The study, published Sept. 29 in the journal Nature, shows that...