Several branching valleys converge and trend down slope from left to right in this image from the Context Camera (CTX) on board the Mars Reconnaissance Orbiter (MRO). These valleys cut through terrain that formed within the last 1 billion years, implying that the valleys themselves are younger. This provides evidence that relatively large amounts of water flowed within specific microenvironments in the otherwise very dry and very cold recent history of Mars. Credit: NASA/JPL/Malin Space Science Systems
