It's now official that water has been found on the moon, and scientists have long seen it on Mars as well. In fact, water is all over the solar system and the rest of the galaxy – and since water is key to life as we know it, these discoveries raise the hope that we are not in fact alone.
The inner planets
Although the moon remains drier than any desert on Earth, new observations from three different spacecraft have uncovered what has been called "unambiguous evidence" of water across the surface of the moon.
On Mars, giant cracks were recently found etched across crater basins that hinted at ancient lakes, and liquid water is thought to have been common across a vast region of ancient Mars billions of years ago. Craters recently even revealed that more water ice is buried closer to the red planet's equator than would be expected, "which implies there was more water in the atmosphere of Mars in the not too distant past," explained Michael Meyer, lead scientist for NASA's Mars Exploration Program.
But liquid and frozen water are not limited to Earth's closest neighbors in space.
More: http://www.space.com/scienceastronomy/090928-water-everywhere.html (http://www.space.com/scienceastronomy/090928-water-everywhere.html)