Ancient Rivers Raged on Mars, Upsetting Geologic Timeline

A new global study of ancient Martian riverbeds shows they are wider than Earth rivers on average, and once carried large volumes of water and runoff. They also flowed until surprisingly recently in Mars’ history, perhaps into the last billion years. This is a puzzle, given the Red Planet’s current desert environment, its thin atmosphere and dim sunlight. These features should have prevented vast water resources even early in the world’s history. Now scientists must puzzle out how both sets

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