Exploring Lunar Mysteries: China’s Chang’e-6 Mission to the South Pole–Aitken Basin
A colossal chasm graces the lunar landscape, residing on the far side of the Moon. Known as the South Pole–Aitken (SPA) Basin, this celestial scar marks the largest and oldest impact crater on the Moon, stretching over 2500 kilometers wide and plunging 8 kilometers deep—nearly vast enough to engulf two Indias and cloak the Himalayas within its depths. Now, China sets its sights on this lunar abyss.
South Pole–Aitken
Believed to have formed eons ago amidst a storm of asteroid bombardment that battered not only Earth but also other bodies within the inner Solar System, the SPA Basin has tantalized scientists with its mysteries. The China National Space Administration (CNSA) aims to unlock its secrets with the forthcoming Chang’e-6 mission, slated for a potential launch as early as May 3rd, according to insiders. “The scientific community eagerly anticipates the return of lunar samples from within the SPA basin,” remarks Carolyn van der Bogert, a planetary geologist at the University of Münster. “The potential for groundbreaking research is immense.”
Following in the footsteps of its predecessor, Chang’e-5, which heralded the return of the first lunar samples since NASA’s Apollo missions, Chang’e-6 carries the torch of exploration. Like its forerunner, the Chang’e-6 mission will deploy a lander to collect and analyze 2 kilograms of lunar soil and rock. An ascender module will ferry these precious samples back to the orbiter for their journey home, culminating in a dramatic descent via parachute within a return capsule, 53 days after liftoff.
It is anticipated that CNSA will extend the spirit of collaboration, mirroring its approach with the sharing of Chang’e-5 samples internationally. Scientists hope that these samples will shed light on the enigmatic origins of the SPA impact, a topic that remains hotly debated. “The timing of the SPA impact is still a matter of contention,” says Kentaro Terada, a cosmochemist at Osaka University. While some speculate that the basin formed 4.3 billion years ago, others propose a later date, potentially aligning with a hypothetical period of intense bombardment within the inner Solar System some 3.9 billion years ago.
Understanding the implications of such a bombardment event extends beyond lunar geology, offering insights into the early dynamics of Earth’s continents and burgeoning life. Yet, the mechanisms driving this cataclysmic event remain shrouded in mystery. While one hypothesis implicates a sudden perturbation in the orbits of Jupiter and other gas giants, recent research casts doubt on the timing of such an event, suggesting it occurred too early in the Solar System’s history.
Analyzing materials melted by the SPA impact holds promise in resolving these longstanding debates. “Chang’e-6 carries the hope of unlocking the mysteries surrounding the late heavy bombardment and its impact on the Moon and the inner Solar System,” van der Bogert remarks. However, success hinges on serendipity, as the majority of anticipated sampling sites comprise basaltic rocks from later volcanic activity. A rare find would be a fragment of lunar mantle, offering a glimpse into the Moon’s deep history. Yet, remote sensing data suggest the likelihood of such a discovery is slim.
In addition to unraveling the mysteries of the Moon’s past, returned samples may provide clues to the stark contrast between its near and far sides. The near side, adorned with smooth, lava-filled plains known as “maria,” boasts a thinner crust compared to its heavily cratered far side counterpart. The divergent compositions and geological features hint at a tumultuous formation history, possibly linked to a colossal impact with Earth in the Moon’s infancy. By dating rocks from both sides, scientists hope to corroborate or refute existing models of lunar formation.
Chang’e-6 exemplifies China’s commitment to international collaboration, hosting payloads from France, Italy, Sweden, and Pakistan. This inclusive approach underscores China’s burgeoning role in space exploration. Over a span of six successful lunar missions, the Chang’e program stands as a testament to China’s technological prowess. Kentaro Terada reflects on this achievement, noting the recent setbacks faced by lunar probes from other nations. “The sustained success of the Chang’e program is truly remarkable,” he acknowledges.