It flowed across the surface of the planet in its near-equatorial regions, the press service of the headquarters of the Chinese Academy of Sciences reportedTASS, April 28.
For the first time, the Chinese Zhuzhong rover discovered traces in the Martian dunes on the territory of the Utopia Plain that water periodically flowed over the surface of Mars in its near-equatorial regions in the relatively recent geological past. This was announced on Friday by the press service of the headquarters of the Chinese Academy of Sciences (KAN).
"The data collected by Zhuzhong on the composition of mineral deposits in these dunes, as well as meteorological data from other rovers, indicate that these relief features arose under the influence of liquid water containing a large amount of salts. This water, in turn, arose as a result of melting snow or ice, which occurs on the surface of the dunes when the ambient temperature decreases," explained Qin Xiaoguang, professor at the Institute of Geology and Geophysics of KANG in Beijing, whose words are quoted by the press service of the university.
The Zhuzhong rover is the central element of the Chinese Tianwen-1 Mars mission, which was sent to the fourth planet of the Solar System in July 2020. In February 2021, the rover reached the orbit of Mars, and in May of the year before last, it made a successful landing on the Utopia plain. In the following months, Zhuzhong studied the structure of the planet's interior and analyzed the composition of local rocks until May 2022, when the rover went into "sleep mode" due to a powerful dust storm.
In the first few months of work on Mars, as noted by Professor Qin Xiaoguang and his colleagues, Zhuzhong comprehensively studied four large Martian dunes and dunes with an age of 0.4-1.4 million years, the mechanisms of formation and structure of which have long been of interest to planetary scientists. To obtain such information, the Chinese rover prepared a large number of detailed images of dunes, and also analyzed their composition using the MSCam multispectral camera and the MarSCoDe laser spectroscope.
When planetary scientists began analyzing these photos and data, they found in them a lot of unusual structures that astronomers did not expect to see on Mars. These include various forms of sand and soil crusts, networks of polygonal cracks in the soil of the fourth planet of the Solar System, layered soil deposits and other characteristic landforms that often occur on the surface of the earth's soil after the movement of water flows.
Their chemical composition also spoke in favor of the similar origin of the Martian deposits discovered by Zhuzhong. The rover's instruments found in them a large number of hydrated molecules of sulfuric acid salts, iron oxide and other minerals formed in the presence of moisture. According to scientists, this suggests that the relief forms discovered by Zhuzhong arose as a result of the recent movement of liquid brine on the surface of the Martian dunes.
According to Professor Qin Xiaoguang and his colleagues, in the past, scientists have already found relatively recent traces of water movement in other regions of Mars, located much closer to the poles than to the equator. The possible presence of traces of the movement of moisture flows in the equatorial regions at the same time caused doubts among many planetary scientists, since scientists doubted that significant reserves of water ice could be concentrated in this part of the planet.
The discovery of "Zhuzhong" casts doubt on this hypothesis and indicates that in the recent past there should have been a lot of frozen water at the equator of Mars. As scientists suggest, these reserves could have been formed several million years ago, when the angle of inclination of the axis of Mars was different and the current equatorial latitudes were located at other latitudes more suitable for the formation of water ice reserves.
