Chinese rover on Mars finds traces of water in sand dunes | Science and the planet

The news comes after expedition leaders admitted that the Zhurong rover has not woken up since it went into hibernation nearly a year ago. The solar arrays may be covered in dust, said Zhang Rongqiao, chief designer of the mission, which would cut off the power supply and render the rover unable to operate.

The six-wheeled Zhurong rover, named after the god of fire in Chinese mythology, was launched in 2020 and will reach Mars in 2021. It drove for a year before it went into hibernation in May last year. The rover ran longer than planned, covering more than a mile (1,921 metres).

Before the rover stopped, she noticed rich salt dunes with cracks and crusts, which researchers say likely mixed with a morning sleet or snow melt a few hundred thousand years ago.

The estimated time range for the formation of cracks and other features of sand dunes on Mars’ Utopia Planitia, a vast plain in the northern hemisphere, ranges from 1.4 million to 400,000 years or even less.

Conditions on Mars during that period were similar to today: rivers and lakes dried up and no longer flowed as they did billions of years ago. In a study published in Science Advances, the Beijing team wrote that studying the structure and chemical composition of these dunes can provide insight into the “potential for water activity” during this period.

“We think it could be a small amount, nothing more than a thin layer of water on the surface,” said Xiaoguang Chen, a study co-author from the Institute of Geology and Geophysics.

The rover has not observed any water in the form of frost or ice, but Chen said computer simulations and observations from other Martian spacecraft indicate that even now at certain times of the year conditions may be right for water to occur.

Planetary scientist Frederic Schmidt of the University of Paris said what was remarkable about the study was how young the dunes were. “This is clearly a new science piece for this area.”

Frost has been observed on Mars since NASA’s Viking missions in 1970, but this light frost in the morning was thought to only occur in certain places and under specific conditions.

Mary Burke of Trinity College Dublin, an expert in Martian geology, said the rover has now “provided evidence that this process is more widespread on Mars than previously identified”. She added that although this discovery is small, it could be important for identifying habitable environments.