SPACE.com -- Water Could Stay Liquid on Mars

Using a planetary environmental chamber – a tank that mimics the atmosphere, temperature, and pressure of other planets – the team exposed various concentrations of briny water to conditions that match Mars' colder, less pressurized environment. Based on these experiments, salty water, it seems, can exist as liquid on Mars.

"It was thought that any liquid on the surface would evaporate almost immediately," Julie Chittenden, a graduate student with the Arkansas Center for Space and Planetary Sciences told SPACE.com. "These brine solutions enable water to stay liquid at colder temperatures. If you expose these brine solutions to cold temperatures, they can exist for a very long period of time."