嫦娥六号月壤揭示巨型撞击造成月背深部物质丢失

Core Insights - The research reveals that a significant impact event approximately 4.25 billion years ago in the South Pole-Aitken Basin not only created the largest crater on the Moon but also caused the loss of certain volatile elements from the Moon's deep material due to high-temperature conditions [1][5] Group 1: Impact of the Research - The study provides critical samples from the Chang'e 6 mission, which collected basalt samples from the South Pole-Aitken Basin, aiding in understanding the effects of large impact events on the Moon's interior [1] - High-precision isotopic analysis of potassium isotopes indicates a significant enrichment of the heavier potassium isotope (K-41) in the Chang'e 6 basalt samples compared to Apollo samples from the Moon's near side [4] - The findings suggest that the loss of volatile elements during the impact may have suppressed volcanic activity on the Moon's far side in later geological periods, offering insights into the differing geological evolution of the Moon's near and far sides [5] Group 2: Methodology and Findings - The research team utilized unique isotopic systems of moderately volatile elements like potassium, zinc, and gallium to reflect the temperature, pressure, and material sources during the impact event [2] - The study systematically ruled out various factors such as cosmic ray exposure and magma activity to confirm that the early large impact event altered the potassium isotopic composition of the Moon's mantle [4] - The high-temperature and high-pressure environment during the impact led to the preferential loss of the lighter potassium isotope (K-39), resulting in a relative enrichment of the heavier K-41 in the remaining material [5]