Veins in Mars' Gale Crater likely formed by 'evaporating ancient lakes', study claims

Scientific researchers on the hunt for signs of water on Mars may have uncovered evidence of ancient lakes after studying mineral 'veins' in the planet's Gale Crater, a new study has claimed. The research, conducted by scientists at the Open University and the University of Leicester, used the Mars Curiosity rover to explore Yellowknife Bay in Gale Crater and analyse the mineralogy of 'veins' found on the Red Planet.

Upon examination, the researchers said the veins were likely "pathways for groundwater". The full study, published in Meteoritics and Planetary Science, suggests the veins formed as the sediments from the ancient lake were buried, heated to about 50C and corroded.

Professor John Bridges, from the University of Leicester Department of Physics and Astronomy, said: "The taste of this Martian groundwater would be rather unpleasant, with about 20 times the content of sulphate and sodium than bottled mineral water, for instance.

"Some microbes on Earth do like sulphur and iron-rich fluids, because they can use those two elements to gain energy. Therefore, for the question of habitability at Gale Crater the taste of the water is very exciting news."

The 'evaporation process' at Yellowknife Bay would likely have led to the creation of such sulphate-rich deposits, the study found. As these then broke up, the veins would be able to form "with pure sulphate in the mudstone of the lake".

The scientists compared water from the Gale Crater with fluids modelled for Martian meteorites that made it to Earth that are thought to have been affected by Martian water long ago. They also compared their findings with rocks previously analysed by previous Mars Exploration rovers.

The scientists said the sediment from the vein formation was found to be high in silicon, sodium, and potassium, but low in magnesium, iron, and aluminium. The study also said that rocks found in Watchet Bay in North Devon, UK, were similar in composition to the mudstone found in the sulphate veins in the Gale Crater.

Ashwin Vasavada, curiosity project scientist from the Nasa Jet Propulsion Laboratory said: "These results provide further evidence for the long and varied history of water in Gale Crater. Multiple generations of fluids, each with a unique chemistry, must have been present to account for what we find in the rock record today."

Most recently, it was hypothesised that Mars used to have far more oxygen than it does now. Researchers claimed to have found high levels of manganese oxides in Martian rocks which they said could only have come from two sources – microbes or atmospheric oxygen. If true, this would have made the Red Planet far more habitable than previously believed.