A NASA space probe has found evidence of brines on Mars, suggesting there could be water on the red planet.

The Curiosity rover, which is studying the planet’s Gale crater, came across traces of a salt called perchlorate near the surface.

Perchlorate salts lower the freezing temperature of water and can absorb water vapour from the atmosphere to form corrosive brines.

The findings suggest an exchange of water between the Martian atmosphere and the surface.

Professor Javier Martin-Torres, who led the study, said: “This is a significant development that could have a major impact on Mars exploration research.

“If there is evidence of water on a planet, then that could sustain living organisms. However, the conditions on the surface of Mars are so harsh it would be impossible for any microbial life to survive, because the UV radiation is so strong it would destroy the DNA of any organisms there.

“As for what is below the surface, we do not know. It would be speculation to suggest there could be life underground, as we simply do not know that, but what this discovery does show is that there is evidence of water on Mars itself.”

Scientists led by Martin-Torres, at the Lulea University of Technology in Sweden, studied humidity and temperature data gathered by the space rover for a full Martian year.

The data suggested a formation of liquid brines in the uppermost soils of the Gale crater during the Martian night.

The brines would then evaporate after sunrise as the ground and air grew warmer.

The findings appear in the latest edition of the journal Nature Geoscience.