Study: Greenhouse gas might have warmed early Mars enough to allow liquid water
The mystery of how the surface of Mars, long dead and dry, could have flowed with water billions of years ago may have been solved by research that included a University of Washington astronomer.
There is evidence that Mars had water at its surface 3.8 billion years ago or before, but scientists are divided on how that might have happened, especially since the sun was about 30 percent fainter back then, thus less able to melt water ice on Mars. (more…)