roda14 @ starvegas55 jajanboss China's Chang'e-5 samples reveal moon's 'persistent but weak' magnetic field 2 billion years ago

A new analysis of samples collected by China’s Chang’e-5 mission has revealed that the moon possessed a weak yet active dynamo magnetic field approximately 2 billion years ago.

Understanding the strength, structure and evolution of the lunar magnetic field is crucial for unraveling its internal structure, thermal history, and surface environment.

Researchers, led by scientists from the Institute of Geology and Geophysics (IGG) under the Chinese Academy of Sciences (CAS), analyzed nine basalt samples returned by Chang’e-5 from the Oceanus Procellarum in the moon’s mid-latitudes.

These rocks offer a unique opportunity to explore the moon’s magnetic history from 3 to 1 billion years ago, a period that remains underexplored. This gap raises the intriguing question of whether the moon experienced a long-lasting “dynamo” effect.

The results show that the moon had a weak dynamo magnetic field during this period, measuring around 2 to 4 microteslas – less than 10 percent of Earth’s current field strength, according to the study published Thursday in Science Advances, where it was featured as the cover story.

This finding helps fill a major gap in our understanding of the moon’s magnetic evolution and suggests that the lunar dynamo lasted at least until its middle years, said Cai Shuhui, a corresponding author of the paper.