There is water on the moon, and it comes from an unlikely source: the sun. That's the conclusion of a new study, after studying soil samples brought back from the original Apollo 11 mission, Cosmos reports. While studies dating back to 2008 have pointed to the existence of water on the moon, until now no one was sure where it came from. Now, University of Tennessee researchers believe that solar winds carry hydrogen ejected from the sun's atmosphere to the moon.
The study will force scientists to rethink the conventional wisdom that water in the inner solar system generally comes from icy meteors or comets. This more reliable source of water could make a lunar colony more feasible, the lead author says. "This water would be of most value as rocket fuel—liquid hydrogen and liquid oxygen," she tells Space.com. "We could use the moon as a jump-board for missions to Mars and beyond." Others aren't as sure. "Extracting the water might be as much trouble as it's worth," one independent geochemist warns.