But new data from NASA shows that the topsoil on Mars contains a surprisingly high amount of water.
Analysis of Mars had scientists believe there were ancient riverbeds on the surface and ice beneath the crust. The topsoil discovery, though, is critical for future manned missions.
"We now know there should be abundant, easily accessible water on Mars," said Laurie Leshin, Dean of Science at the Rensselaer Polytechnic Institute. "When we send people, they could scoop up the soil anywhere on the surface, heat it just a bit, and obtain water."
Scoops of soil were fed into Curiosity's Sample Analysis at Mars (SAM) analytical suite, which allows the rover to identify chemical compounds.
"About 2 percent of the soil on the surface of Mars is made up of water, which is a great resource, and interesting scientifically," said Leshin.
Previous Mars rovers found evidence of ancient water there, but unlike the water just discovered, the water was extremely acidic.
The rover will continue analysis on Mars, and scientists believe that they will find evidence of organic compounds. So far, analyses have not returned evidence that organic compounds exist or have existed on Mars.