What is the 'infancy' of the moon, Earth's closest neighbor? In order to solve this puzzle, the team of Professor Wang Shuijiong from the Institute of Geology and Geophysics of the China University of Geosciences (Beijing) and the team of researcher Li Qiuli from the Institute of Geology and Geophysics of the Chinese Academy of Sciences jointly conducted in situ isotopic dating analysis of a lunar meteorite named NWA 14729, and gave a new answer: the "magma ocean" of the moon may have been formed 4.5 billion years ago, and rapidly cooled and solidified in less than 100 million years. This discovery challenges past knowledge and provides key clues for understanding the early evolution of the moon. The relevant research results were recently published in the international academic journal "Scientific Progress". According to the Great Collision Hypothesis, a Mars sized planet called Theia violently impacted the young Earth, throwing a large amount of material into space and eventually condensing to form the Moon. The energy released by this impact was so enormous that the newly born moon was almost completely covered by molten magma, forming a "magma ocean" thousands of kilometers deep. Later, it slowly cooled down, forming today's lunar crust and mantle. But when did this' magma ocean 'start and end? A new discovery has been made in the study of this lunar meteorite named NWA 14729. Wang Shuijiong introduced, "This is a magnesian suite meteorite from the highlands of the moon, containing special zirconium containing minerals (such as zircon, clinopyroxene, etc.), which act as' time capsules' to record the chemical information of the early moon." The research team used high-precision ion probe technology (SIMS) to measure the lead isotope composition of these minerals and finally calculated their ages - about 4.406 billion years, with an error of only ± 3.2 million years, making it one of the most accurate early lunar age data currently available. More importantly, these minerals exhibit a characteristic of "high initial lead" (HIP), which means that the rock has a very high level of radiogenic lead from the beginning of its formation, indicating that it originated from an older, uranium rich magma source area and underwent a long period of evolution to accumulate so much radiogenic lead. Through computer simulations, the research team inferred that the lunar "magma ocean" may have formed 4.5 billion years ago and cooled in a relatively short period of time, even considering extreme conditions, its duration would not exceed 100 million years. This discovery challenges the mainstream view in the international academic community. In the past, scientists generally believed that the moon only completely solidified about 4.35 billion years ago. But this new study suggests that 4.35 billion years may not be the end of the 'magma ocean', but rather a record of other major thermal events that the moon later experienced, such as large-scale meteorite impacts or mantle melting. Li Qiuli said, "This discovery will prompt us to rethink the early evolution model of the moon and also revise the lead evolution model in young lunar mare basalt