For the first time, scientists have confirmed that the impact cratering rates on the near and far sides of the moon are essentially consistent, laying a solid basis for the establishment of a globally unified lunar chronology system, according to the Science and Technology Daily.<\/p>\n
A research team led by the Chinese Academy of Sciences’ Institute of Geology and Geophysics successfully revised the decades-old lunar impact crater chronology model by analyzing remote sensing images.<\/p>\n
Their study reveals a uniform impact flux across both hemispheres, provides evidence that early lunar impact events followed a smooth trend of gradual decline, rather than the dramatic fluctuations previously hypothesized. Their findings were published in Science Advances on Thursday.<\/p>\n
Knowing the age of the lunar surface is crucial to understanding the moon’s geological evolution. For decades, scientists have estimated the age of unsampled regions by counting impact craters, with a higher density indicating an older surface.<\/p>\n
However, the existing crater chronology method relied entirely on samples from the near side of the moon, and the oldest specimens date back no more than 4 billion years. This limitation fueled ongoing debate about the moon’s early impact history, including competing hypotheses such as the Late Heavy Bombardment.<\/p>\n
A breakthrough came in June 2024, when China’s Chang’e-6 mission returned 1,935 grams of lunar samples from the Apollo Basin, which is located within the South Pole-Aitken Basin on the moon’s far side.<\/p>\n
Analysis of these samples identified two key rock types: young basalt aged at 2.807 billion years old, and ancient norite formed 4.25 billion years ago.<\/p>\n
The norite, in particular, originated from magma that crystallized after the giant impact event that formed the South Pole-Aitken Basin — the moon’s largest and oldest impact structure. These samples have served as a critical anchor point in reconstructing the early history of the moon.<\/p>\n
The researchers systematically mapped crater densities across the Chang’e-6 landing area and the broader South Pole-Aitken Basin using high-resolution remote sensing imagery.
\nBy then integrating this new density data with all historical sample data from the Apollo, Luna and Chang’e-5 missions, they constructed a new, more comprehensive lunar impact chronology model.<\/p>\n
Their results show that far-side crater density data aligns perfectly with the confidence interval of the near-side-derived model. “This indicates that the impact flux was homogeneous across the entire moon, providing a reliable basis for a unified global lunar chronology,” said Yue Zongyu, the study’s lead author and a researcher at the institute.<\/p>\n
Yue noted that the study fundamentally advances our understanding of lunar impact history and underscores the pivotal scientific value of the Chang’e-6 samples. The refined chronology will serve as a more accurate reference not only for lunar study but also for the dating of surfaces of other planetary bodies in the solar system.<\/p>\n","protected":false},"excerpt":{"rendered":"
For the first time, scientists have confirmed that the impact cratering rates on the near and far sides of the moon are essentially consistent, laying a solid basis for the establishment of a globally unified lunar chronology system, according to the Science and Technology Daily. A research team led by the Chinese Academy of Sciences’ […]<\/p>\n","protected":false},"author":5,"featured_media":71792,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[30,17],"tags":[],"ppma_author":[213],"class_list":{"0":"post-71791","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-latest","8":"category-world"},"yoast_head":"\n