Chang'e-6 Mission Reveals New Insights into Moon's Impact History and Far Side Evolution

A Chinese research team has made a significant discovery regarding the Moon's history. Through detailed analysis of lunar soil collected by the Chang'e-6 mission, they have precisely dated the formation of the Apollo Basin to 4.16 billion years ago. This finding has important implications for understanding the early solar system.

The research, led by Academician Xu Yigang of the Guangzhou Institute of Geochemistry, involved the analysis of a small lunar soil sample. Within this sample, the team identified rare rock fragments, formed from impact-melted rocks during the Apollo Basin's creation. These fragments served as valuable "rock clocks," providing a record of the impact event.

By dating these fragments and combining the data with remote-sensing imagery and geochemical information, the researchers were able to confirm the Apollo Basin's formation age. This discovery extends the timeline of the Moon's "impact storm" by at least 100 million years.

The Moon's surface is marked by numerous impact basins, largely resulting from collisions with celestial bodies approximately 3.8 billion years ago. Scientists have debated whether the intensity of these impacts declined gradually or spiked suddenly. The precise dating of the Apollo Basin provides crucial evidence to address this debate.

The Apollo Basin, a major secondary impact structure within the Moon's South Pole-Aitken Basin, is believed to mark the beginning of the Moon's late-stage impact events. This study suggests that the impact intensity declined gradually, rather than abruptly. These findings are expected to significantly alter our understanding of the Earth-Moon system's evolution.

In addition to the Apollo Basin research, other studies based on samples from the Chang'e-6 mission have revealed new insights into the Moon's far side. These studies have unveiled the history of the lunar far side for the first time, including information on magmatic activity, ancient magnetic fields, mantle water content, and mantle evolution.