A joint research team led by the Ion Probe Center of the Institute of Geology of the Chinese Academy of Sciences, under the organization of the China National Space Administration, released the latest scientific findings from the Chang’e-6 lunar far-side samples. The research has been published in the latest issue of the journal Science.
China’s Chang’e series lunar probes, relay satellites, and the Long March series carrier rockets used for their launches were all developed by China Aerospace Science and Technology Corporation. The Chang’e-6 mission marked the first-ever successful retrieval of samples from the far side of the moon in human history.
The study revealed that the basalt compositions of samples from both the far and near sides of the moon are similar. The primary basalt formation age of the studied samples is approximately 2.823 billion years old, and its characteristics support the lunar magma ocean model. The research also suggests that the impact event that formed the South Pole-Aitken Basin may have altered the early lunar mantle.
The lunar magma ocean model was previously established based on samples from the moon's near side. This model proposes that in the moon’s early formation stage, a global-scale molten ocean existed. As this magma ocean cooled and crystallized, minerals with lower density floated to form the lunar crust, while denser minerals sank to form the lunar mantle. The remaining melt, enriched with incompatible elements, formed the KREEP layer.
In this latest study, the research team analyzed the Chang’e-6 lunar far-side samples and discovered that the KREEP layer also exists on the moon’s far side. The similarity in basalt composition between the far and near sides indicates that a global magma ocean may have spanned the entire moon.
Additionally, the study found that the lead isotope evolution paths in basalts from the far and near sides are different, indicating variations in their evolutionary processes after magma ocean crystallization. Large-scale impact events on the moon’s surface, particularly the one that created the South Pole-Aitken Basin, likely changed the physical and chemical properties of the moon’s mantle.
(Executive editor: Wang Ruoting)
