Mars ‘had system of lakes’

Scientists say images of craters taken by European and American space probes show it was likely there was once a planet-wide system of underground lakes on Mars.

Data collected by Nasa and ESA probes orbiting the red planet have provided the first geological evidence for an ancient Martian groundwater system, according to a study by researchers in Italy and the Netherlands published in the Journal of Geophysical Research.

Francesco Salese, one of the scientists involved, said the findings confirmed earlier models and smaller-scale studies, and that the underground lakes may have been connected.

The researchers said flow channels, pool-shaped valleys and fan-shaped sediment deposits seen in dozens of kilometres-deep craters in Mars’ northern hemisphere would have needed water to form.

Co-author Gian Gabriele Ori said an ocean some scientists speculated Mars may have had between three and four billion years ago could have been connected to the underground lakes.

The researchers also saw signs of minerals such as clay on Mars that would have required long periods of exposure to water to form.

Meanwhile, Nasa’s newest Mars lander has started digging into the red planet, but has hit a few snags.

The German Aerospace Centre said yesterday its drilling instrument on the InSight lander had hit what appeared to be a couple of stones. It only managed to dig between 18 and 50 centimetres, far short of the first dig’s goal. Over time, the team is shooting for a depth of up to five metres, to measure Mars’ internal temperature. –AP