The sinuous channels carved onto the Martian surface, first seen 3 decades ago, have convinced most scientists that water once flowed on the Red Planet. But where did the water come from?
A new analysis of a Mars meteorite that fell to Earth suggests that ancient Martian magma--molten rock from deep within the Red Planet--contained significant amounts of water before it erupted on the planet's surface. Before it solidified, the molten rock contained as much as 1.8 percent water, Timothy L. Grove of the Massachusetts Institute of Technology and Harry Y. McSween Jr. of the University of Tennessee in Knoxville and their colleagues report in the Jan. 25 Nature.
When such water-bearing magma reached the surface and cooled, water vapor would have escaped into the atmosphere, much like bubbles from a bottle of soda. The vapor could then have rained down to the surface. The analysis of the Mars meteorite, known as Shergotty, doesn't explain why the Martian interior wou