Core Insights - The research reveals that the Moon, previously thought to be "dormant" for 3 billion years, has experienced volcanic activity during this period, challenging existing beliefs about lunar evolution [1][3][4] - The study, published in the journal "Science Advances," was conducted by a team from the Guangzhou Institute of Geochemistry and Hong Kong University, focusing on samples returned by China's Chang'e 5 and Chang'e 6 missions [1][4] Group 1: Volcanic Activity - The Chang'e 5 and Chang'e 6 missions returned basalt samples that are 2 billion and 2.8 billion years old, respectively, indicating that volcanic eruptions occurred during the Moon's "dormant" phase [1][3] - Two types of basalt were identified in the Chang'e 6 samples, one originating from over 120 kilometers deep in the mantle and the other from a shallower depth of 60 to 80 kilometers [3] Group 2: Thermal Dynamics - The research team proposed a new thermal dynamic mechanism where magma, trapped in the upper mantle, can transfer heat upward, leading to partial melting and volcanic eruptions [3][4] - The study found that the heat sources for lunar volcanic activity changed significantly around 3 billion years ago, shifting from a complex mix to a dominant upward heat transfer mechanism [4] Group 3: Lunar Composition and Evolution - Analysis of remote sensing data suggests differences in the composition of the lunar mantle between the near and far sides of the Moon, with the near side having more titanium-rich minerals [4] - The findings provide new insights into the asymmetric evolution of the Moon and contribute to a better understanding of volcanic activity on other small celestial bodies [4]

Core Insights - Chinese scientists have made significant progress in understanding the "ultra-depleted" characteristics of the lunar mantle material from the South Pole-Aitken basin, based on samples collected by the Chang'e 6 mission, providing crucial information for understanding the early shell-mantle evolution of the Moon [1][10] Group 1: Research Findings - The study reveals that the lunar mantle material is extremely "depleted," lacking elements that easily melt and rise with magma, indicating a unique composition of the lunar interior [4][6] - The research team has proposed two models to explain the extreme "ultra-depleted" characteristics: the "primordial depletion" model and the "post-impact modification" model [5][6] Group 2: Models Explained - The "primordial depletion" model suggests that during the Moon's formation, a massive magma ocean cooled unevenly, leading to the separation of heavy minerals to the bottom and leaving behind a depleted mantle that requires minimal partial melting to form basalt [6][7] - The "post-impact modification" model posits that the South Pole-Aitken basin's giant impact significantly altered the lunar mantle, extracting a large amount of magma and resulting in an extremely depleted state that also requires less partial melting to form basalt [6][7] Group 3: Implications - If the "primordial depletion" model is validated, it implies that the basalt from Chang'e 6 originates from a deep, undisturbed mantle, suggesting that the differences observed between the lunar front and back may be a result of later geological processes [7][10] - If the "post-impact modification" model holds true, it indicates that giant impacts can reshape not only the surface but also the internal composition of celestial bodies, providing new insights into the early differentiation of planetary bodies in the solar system [7][10]