A Third of Mars Could Have Been Underwater 167
Matt_dk writes "An international team of scientists who analyzed data from the Gamma Ray Spectrometer onboard NASA's Mars Odyssey reports new evidence for the controversial idea that oceans once covered about a third of ancient Mars.
'We compared Gamma Ray Spectrometer data on potassium, thorium and iron above and below a shoreline believed to mark an ancient ocean that covered a third of Mars' surface, and an inner shoreline believed to mark a younger, smaller ocean.'"