The latest research from China's Zhurong rover shows that its landing site has stronger Martian geomorphological characteristics than other Martian landing sites. Its surface is shaped by wind or water, and these preliminary findings suggest that Zhu Rong is expected to bring insights into the evolution of the surface environment in the lowlands of mars' northern hemisphere.
The above findings were published in the authoritative academic journal Nature-Earth Sciences on March 8, Beijing time. Professor Ding Liang of the State Key Laboratory of Robotics and Systems/School of Mechanical and Electrical Engineering of Harbin Institute of Technology and his colleagues analyzed the measurements of the landing site area collected by Zhu Rong in the first 60 Martian days, found evidence that the landing site area was more obvious than the geomorphological characteristics of other Martian landing sites, and studied the physical properties and geomorphological characteristics of the Martian soil at the landing site.
The landing site of the Tianwen-1 probe and the Zhurong rover and its surrounding craters, picture from the paper
In May 2021, the Tianwen-1 rover and the Zhurong rover landed in the low-lying areas of the Utopia Planitia in the northern hemisphere of Mars. The Utopian Plains is a volcanic region, the largest plain on Mars, with a diameter of 3,200 kilometers and dating back about 3.32 billion to 3.36 billion years ago. Scientists speculate that the plain once had a large amount of liquid water or ice because there may have been an "ancient ocean" in the northern hemisphere of Mars, while the utopian plain is located within the presumed ancient coastline. Therefore, it is of great significance to analyze the topography and material composition of the landing area to explore its geological evolution history and verify the "ancient ocean" hypothesis of Mars.
The "60 Martian days" in research work means 61.6 Earth days. Since Martian days represent solar days on Mars, a "day and night" time, averaging 24 hours, 39 minutes, 35.24409 seconds, Martian days are nearly 2.7% longer than Earth days.
"Zhu Rong" rover, picture from the paper
The Zhurong is 1.85 meters high and weighs about 240 kilograms. This time, the researchers used the "Zhurong" motion data and camera images to determine that the distance it traveled south in the first 60 Martian days was 450.9 meters, and by analyzing the interaction force of the "Zhurong" wheel and the terrain below and the rutted images taken by the obstacle avoidance camera, the soil on the surface of Mars at the landing site had high bearing strength and cohesion, and also identified the landforms in the area that matched the characteristics of wind erosion (such as sand ridges, ripples, erosion pits and rock textures), of which the wind-forming bed form was dominated by transverse sand ridges , the local wind direction is northeast. At the same time, the landing area shows a gentle topographic condition, and the main geological features of its surface include aeolian bed morphology, small craters and rocks.
These preliminary findings suggest that the landing position of the Zhurong rover has more obvious and easy-to-study geomorphological features than other Martian landing sites, which is expected to bring more insights into the evolution of the surface environment in the lowlands of the northern hemisphere of Mars.
Geological features of the landing sites of Zhurong and Tianwen-1, pictured from the paper