once thought to be lifeless, Mars probably had water lots of it

Scientist Says Mars Once Had Oceans
By Dave Mosher

(June 14) - Since 1991, planetary scientists have floated the idea that Mars once harbored vast oceans that covered roughly one-third of the planet. Two long shore-like lips of rock in the planet's northern hemisphere were thought to be the best evidence, but experts argued that they were too "hilly" to describe the smooth edges of ancient oceans.

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