The Hong Kong Polytechnic University (PolyU) proudly supports the nation’s current lunar exploration, Chang’e-4 lunar probe, with advanced technologies, namely the design and development of an advanced Camera Pointing System, and an innovative lunar topographic mapping and geomorphological analysis technique in landing site charaterisation for the space craft.
Chang’e-4 is the first lunar mission in the world to land on the far side of the Moon. The selection of a safe landing site with scientific value for Chang’e 4 is therefore one of the major tasks for the exploration. To support the nation’s lunar endeavour, Dr Bo WU, Associate Professor of the Department of Land Surveying and Geo-Informatics, leads a team to conduct a research titled “Chang’e-4 Landing Site - Topographic and Geomorphological Characterisation and Analysis”.
Funded by the China Academy of Space Technology (CAST), Dr Wu’s team has started the project since March 2016. The team amassed a large amount of lunar remote sensing data from multi-sources to create high-precision and high-resolution topographic models at the northwestern South Pole - Aitken basin on the far side of the Moon, a potential landing region for the Chang’e-4. It then analysed in detail the terrain slopes, terrain occlusions to sun illumination and telecommunication, crater distribution, rock abundances, and geological history of the region. These analyses helped the team to put forward a sound and evidenced-based proposal of possible landing sites.
Also joining this historical mission is Prof Kai-leung YUNG, PolyU’s Associate Head of Department of Industrial and Systems Engineering. He led a team that developed the Camera Pointing System (CPS) jointly with CAST.
The CPS weighs 2.8 kg and measures 85 cm (length) by 27 cm (width) and 16 cm (depth). Mounted on the upper part of the lander of Chang’e-4, CPS is capable of moving vertically by 120 degrees and rotating sideway by 350 degrees. It is deployed for capturing images of the moon as well as facilitating movement of the lunar rover. This sophisticated space tool will be able to withstand the vast difference in temperature and function in the Moon’s gravity (i.e. one sixth of Earth’s gravity).
The CPS is the first Hong Kong-made and developed instrument being deployed for the nation’s lunar exploration programme since its launch in 2007. It was delicately manufactured in PolyU’s Industrial Centre, a key member in the project that played a pivotal role in producing space instruments to meet the stringent requirements in design and features for space deployment.
The expert teams have been working to support the nation’s lunar missions for years. The CPS developed by Prof Yung’s team was first adopted by Chang’e-3 launched in 2013. Its functionalities and performance were proved to have met the stringent requirements as it operated smoothly as planned after the landing of the space craft. Dr Wu also worked on the topographic mapping and analysis of the landing site of the Chang’e-3 mission in 2013, and made contributions to the strategic planning and selection of the landing site for Chang’e-3.
The two PolyU teams will continue to contribute to the nation’s space exploration programmes, including Chang’e-5 lunar mission and the nation’s first mission to explore Mars later.