News Planetary Science

Shifting Ocean: Tipsy Mars may explain undulating shoreline

By Ron Cowen

- More than 2 years ago

By proposing that the Red Planet was tipped halfway over on its side several billion years ago, astronomers this week provide a new perspective on—and new support for—the long-standing notion that Mars once held a vast ocean.

RED PLANET, BLUE OCEAN. Mars as it might have appeared more than 2 billion years ago. Researchers propose that an ocean then filled a lowland basin occupying the north polar region, which was tipped significantly from its modern position.