China achieved a significant milestone in space exploration by landing the uncrewed Chang’e-6 spacecraft on the far side of the moon on Sunday. This mission marks a pivotal moment in China’s ambitious lunar program, aiming to retrieve the world’s first rock and soil samples from the moon’s dark hemisphere. The successful landing of Chang’e-6 at 6:23 am Beijing time in the South Pole-Aitken Basin, a colossal impact crater, underscores China’s increasing stature in the global space race, where nations such as the United States aspire to utilise lunar resources to support long-term astronaut missions and establish moon bases within the next decade.
The China National Space Administration (CNSA) highlighted the mission’s complexity, stating that it “involves many engineering innovations, high risks, and great difficulty.” The Chang’e-6 lander is equipped with a suite of scientific instruments and its own launcher to execute planned scientific exploration tasks. This mission represents China’s second successful landing on the moon’s far side, a region no other country has reached. The lunar hemisphere facing away from Earth is characterised by its rugged terrain, dotted with deep, dark craters that pose substantial challenges to communications and robotic landing operations.
Lunar and space experts involved in the Chang’e-6 mission emphasised the high-risk nature of the landing phase. Neil Melville-Kenney, a technical officer at the European Space Agency collaborating with China on one of the Chang’e-6 payloads, stated, “Landing on the far side of the moon is very difficult because you don’t have line-of-sight communications, you’re relying on a lot of links in the chain to control what is going on, or you have to automate what is going on.” He added, “Automation is very difficult especially at high latitudes because you have long shadows which can be very confusing for landers.” Landing on the south pole of the moon is especially difficult considering the rough terrain that is littered with craters and deep trenches that render it impossible for space shuttles to have a smooth landing, that is to say, until today.
The Chang’e-6 mission’s technical intricacies are noteworthy. The far side of the moon, which perpetually faces away from Earth, requires relay satellites to maintain communication between the lander and mission control on Earth. The CNSA employed the Queqiao relay satellite to facilitate this communication, ensuring that data and commands could be transmitted despite the lack of direct line-of-sight.
Furthermore, the lunar terrain in the South Pole-Aitken Basin presents unique challenges. The basin is one of the largest and oldest impact craters in the solar system, with a diameter of approximately 2,500 kilometres and a depth of around 13 kilometres. The rugged terrain, combined with the region’s long shadows and low angles of sunlight, complicates navigation and landing procedures. The Chang’e-6 mission utilised advanced autonomous navigation and landing technologies to overcome these obstacles, demonstrating China’s growing expertise in space exploration.
Chang’e-6’s payload includes a variety of scientific instruments designed to conduct detailed analyses of the lunar surface. These instruments will study the composition, structure, and history of the lunar soil and rocks, providing valuable data for understanding the moon’s geological evolution and potential resources. The mission also includes a small launcher to return the collected samples to Earth, a feat that has never been accomplished from the far side of the moon.
This mission is part of China’s broader lunar exploration program, which includes future plans for crewed missions and the establishment of a lunar research station. The successful landing of Chang’e-6 not only enhances China’s status as a major space-faring nation but also contributes to the international community’s understanding of the moon’s far side. The CNSA’s collaboration with international partners, such as the European Space Agency, highlights the global interest and cooperative efforts in lunar exploration.
In the historical context of lunar exploration, only a few nations have successfully sent missions to the moon. The United States remains the only country to have landed humans on the moon, starting with the Apollo 11 mission in 1969. The Soviet Union and India have also achieved robotic lunar landings. China’s success with Chang’e-6 reinforces its position among these leading spacefaring nations and sets the stage for future advancements in lunar exploration and utilisation.