Why did Mars dry out? New study points to unusual answers - Phys.org

Mars once ran red with rivers. The telltale tracks of past rivers, streams and lakes are visible today all over the planet. But about three billion years ago, they all dried up—and no one knows why.

Mars once ran red with rivers. The telltale tracks of past rivers, streams and lakes are visible today all over the planet. But about three billion years ago, they all dried upand no one knows why. … [+5618 chars]

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