嫦娥六号月壤研究：修正月球“时间标尺”证实两面撞击通量一致

Core Viewpoint - Chinese scientists have made significant progress in lunar research by revising the long-standing lunar impact crater chronology model, confirming that the impact flux on the moon's front and back is consistent, and indicating a smooth decline in early impact flux, which contradicts the "late heavy bombardment" hypothesis [1][3][5]. Group 1: Research Findings - The study was conducted by scientists from the Chinese Academy of Sciences, utilizing remote sensing images and published in the journal "Science Advances" [3]. - The research established a new impact crater chronology model based on samples returned by the Chang'e 6 mission, which included 1,935 grams of lunar soil from the South Pole-Aitken (SPA) basin [5]. - The analysis revealed young basalt dated at approximately 2.807 billion years and ancient rock at 4.25 billion years, providing critical "anchors" for understanding the moon's early history [5]. Group 2: Methodology and Results - The research team used high-resolution remote sensing images to statistically analyze the density of impact craters larger than 1 kilometer in the Chang'e 6 landing area and the entire SPA basin [5]. - The results indicated that the impact crater density on the moon's back is highly consistent with that on the front, falling within the 95% confidence interval of the previously established model based on front samples [5]. - The new model suggests that early lunar impact events occurred in a smooth decline rather than a chaotic process, challenging existing hypotheses regarding the moon's early impact history [7].