Reporters learned from the Chinese Academy of Sciences Guangzhou Institute of Geochemistry on the 20th that Xu Yigang, an academician of the CAS Member and a researcher of the Chinese Academy of Sciences Guangzhou Institute of Geochemistry, made the first accurate determination of the lunar Apollo basin topography 4.16 billion years ago through high-precision chronological research on Chang'e-6 lunar soil samples. This discovery provides crucial evidence for revealing that the moon has been hit by an "impact storm" within the solar system, known as late stage heavy bombardment. On that day, the research results led by the team were published in the international journal Nature Astronomy. The giant impact basins scattered on the surface of the moon are mostly remnants of small celestial body impacts in the solar system about 3.8 billion years ago. Did this' impact storm 'in the solar system experience a sudden increase in intensity or a gradual decrease between approximately 4 billion and 3.8 billion years ago? There has always been debate in the scientific community. The controversy stems from the lack of precise age data for key impact basins on the moon. ”Xu Yigang introduced that the Apollo Basin, where the Chang'e-6 sampling point is located, is located inside the Aitken Basin at the South Pole of the Moon. It is the largest secondary impact structure in the region, and its formation age may mark the start time of the late heavy impact event, thus becoming the key to solving the mystery of this "impact storm". The research team discovered three special rock fragments with a diameter of 150-350 microns in only 3.5 grams of lunar soil. These rock fragments are impact melted rocks produced during the formation of the Apollo Basin, and are the most ideal "rock clock" for recording impact events. The research team accurately determined the age of the rock debris, and combined various information such as remote sensing images and geochemical data to ultimately confirm that the 4.16 billion years recorded by the rock debris is the formation age of the Apollo Basin. The newly obtained age from this study advances the start time of the late lunar heavy bombardment event by at least 100 million years, updates the start time of the "impact storm," overturns the "catastrophe theory" of lunar impact flux, and reveals the early dynamic evolution laws. The impact flux analysis in this study indicates that the impact flux during the late lunar heavy bombardment period showed a gradual decline trend, which does not support the hypothesis of a surge in impact flux between 4 billion and 3.8 billion years. ”Xu Yigang emphasized that the study of Chang'e-6 samples will continue to promote humanity's re understanding of the evolution of the Earth Moon system. (New Society)