Yesterday, however, scientists announced the discovery of several hidden impact craters, buried under Mars' northern plains. Herbert Frey of NASA’s Goddard Space Flight Center presented the findings at the annual meeting of the Geological Society of America in Boston. Frey said the lowlands may actually have formed first. "That means that at whatever early time conditions permitted liquid water to exist on Mars, there was a northern lowland into which that water could drain," he said. "So it is quite possible that a shallow ocean may have existed on Mars very early in its history, as some have suggested based on completely different data."

http://www.geosociety.org/pubntrst/pr/01-56.htm

Have a good weekend all.
See ya, VINCE