Mars was very cold and dry, ... All the features we are seeing reinforce that view, that's it's cold and dry today.
These are new landforms that have never been seen before on Mars. We see features that look like gullies formed by flowing water and the deposits of soil and rocks transported by these flows.
These are new landforms that have never been seen before on Mars, ... We see features that look like gullies formed by flowing water and the deposits of soil and rocks transported by these flows.