China’s First Landing on Mars Supported by Research of LSGI Academic

The landing of Chinese spacecraft Tianwen-1 on Mars in mid-May 2021 has made aerospace history. It was the first time in the world that a spacecraft has completed orbiting, landing and roving in one single mission. Two PolyU research teams had supported the successful mission. One was led by Prof. Bo Wu of the Department of Land Surveying and Geo-informatics (LSGI). From 2017 to 2020, his team had shortlisted three potential landing regions on Mars, one of which was the southern Utopia Planitia, the largest recognised impact basin in the northern hemisphere of Mars. It was eventually chosen as the target landing region after detailed topographic and geomorphological mapping and analysis. Using the high-resolution images sent from Tianwen-1 of the target landing region covering an area of about 11 times larger than the size of Hong Kong’s territory, Prof. Wu and his team generated high-resolution and high-precision 3D digital topographic models of the target landing region using the integrated 3D mapping model developed by them to analyse the detailed topography and identify large slopes hazardous for landing. They also developed AI-based techniques for more automated and robust analysis of geomorphological features like craters and rocks from the high-resolution images in a short period of time. More than 670,000 craters, over two million rocks, and hundreds of volcanic cones distributed over the target landing region were analyzed in 1.5 months, achieving much higher efficiency in the automatic extraction of rocks and craters with an accuracy of about 85%.

The spacecraft for the Tianwen-1 probe comprises an orbiter, a lander and the Zhurong rover. In collaboration with the China Academy of Space Technology (CAST), the latest mission aims to obtain scientific exploration data on the Red Planet. With orbiting and landing completed, the Mars rover Zhurong is set to begin its exploration. The whole world is waiting to see what it finds.