A series of research findings by Chinese scientists on the samples collected by the Chang'e-6 mission from the Moon's far side have unveiled the volcanic activity, ancient magnetic field, water content and geochemical characteristics of the moon mantle, shedding the first light on the evolutionary history of its far side.
Four studies by the research teams from the Institute of Geology and Geophysics, the National Astronomical Observatories, both under the Chinese Academy of Sciences, Nanjing University, and other institutions were published in the latest issue of Nature.
The CAS held a press conference on Wednesday to introduce these research findings.
In 2024, Chang'e-6 made history by bringing 1,935.3 grams of lunar far-side samples back to Earth.
These samples were collected from the South Pole-Aitken (SPA) Basin, the largest, deepest and oldest basin on the Moon, which provided a rare opportunity to clarify the compositional differences between the near and far sides and to unravel the long-standing mystery of their asymmetry.
Over the past year, Chinese scientists have achieved multiple pioneering breakthroughs through the study of the Chang'e-6 samples.
One notable outcome is the research on basalts collected from the SPA Basin. They formed after the lunar mantle melted, generating magma that erupted onto the lunar surface.
Through petrographic and mineral chemical analyses of the basalts formed about 2.8 billion years ago, researchers have figured out their chemical composition.
Isotopic analysis further unveils that the mantle source region beneath the Chang'e-6 landing site is extremely depleted in incompatible elements -- those that tend to concentrate in melts.
Based on these findings, the research team proposed two possible formation mechanisms for the mantle source of basalt.
"One view holds that certain characteristics of the lunar mantle are primordial or that these features have existed since the Moon's formation about 4.5 billion years ago. The other view suggests that a massive impact event occurred during the formation of the SPA Basin, altered parts of the mantle, leading to the depletion of certain elements observed in the collected basalts,” said Zhou Qin, associate research fellow at the National Astronomical Observatories.
As the Moon's revolution cycle is the same as its rotation cycle, the same side always faces Earth. The other face, most of which cannot be seen from Earth, is called the far, or dark, side of the Moon. This term doesn't refer to visible darkness, but rather the mystery shrouding the Moon's largely unexplored terrain.
The Moon's near and far sides exhibit significant differences in morphology, composition, crustal thickness and magmatic activities. However, the mechanisms behind these disparities remain unresolved, representing a key issue in lunar science. Previously, scientific understanding of the far side relied primarily on remote sensing studies, scientists say.
Samples collected by Chang'e-6 shed light on evolution of moon's far side
