Chang'e-6 samples reveal new views on lunar magnetic field

Rock samples collected from the moon's far side by China's Chang'e-6 lunar probe indicate an unexpected resurgence in the moon's magnetic field strength 2.8 billion years ago, which challenges the previous findings from the US Apollo mission, which suggested that the moon's magnetic field declined about 3.1 billion years ago and has remained in a low-energy state since then.

The analysis of these samples, published on Thursday in the journal Nature, marks the first-ever paleomagnetic data obtained from the moon's far side, and offers critical insights into the intermediate evolutionary stages of the lunar dynamo, the geophysical mechanism that generated the moon's magnetic field in the past, according to Guangming Daily. 

On June 25, 2024, the Chang'e-6 lunar probe returned to Earth with 1,935.3 grams of lunar samples collected from the previously unexplored far side of the moon.

Cai Shuhui from the Institute of Geology and Geophysics (IGG) under the Chinese Academy of Sciences, also first author of the paper, said that the Earth has a "magnetic field generator"—the movement of the conductive fluid in the Earth's liquid outer core acts like a "generator," which generates a magnetic field enveloping the Earth like a protective shield. 

This magnetic field shields the planet from cosmic rays and protects essential elements for habitability, such as the atmosphere and water, creating an environment suitable for the proliferation of life.

The Moon once had a similar "magnetic field generator," which ceased functioning long ago. Studies of the ancient magnetic field strength based on samples returned by the US Apollo mission indicate that the Moon had a relatively active "generator" producing a magnetic field between 4.2 billion and 3.5 billion years ago. This magnetic field decreased by an order of magnitude around 3.1 billion years ago, and again declined between 1.5 billion and 1 billion years ago, ultimately ceasing to function completely at some point after 1 billion years ago.

The Chang'e 6 mission has achieved the first-ever sample collection from the far side of the Moon, with the primary eruption age of the basalt being 2.8 billion years. This provides an unprecedented opportunity to understand the temporal and spatial evolution of the Moon's "magnetic field generator."

Researchers from the IGG studied the sample and discovered the ancient magnetic field strength of the sample found to be higher than previously thought. Cai said this suggests that after a sharp decline in the lunar magnetic field 3.1 billion years ago, there may have been a rebound or reactivation around 2.8 billion years ago. 

IGG's analysis indicates that this could be due to a change in the main energy source of the "generator" or a reinforcement of the initial driving mechanism.

IGG's study is not only the first information about the ancient magnetic field on the Moon obtained by humans, but also provides key information to understanding the evolution of the Moon's magnetic field, according to Guangming Daily.

Chinese FM responds to S.Korean FM’s comments on continuing to develop bilateral relations with China regardless of domestic situation

In response to the South Korean Ministry of Foreign Affairs' comments stating that South Korea will continue to develop bilateral relations with China and maintain necessary communication despite recent domestic developments following President Yoon Suk-yeol's comments on cases involving Chinese nationals, Chinese Foreign Ministry spokesperson Mao Ning said China has noted the remarks and had expressed its position on South Korea's comments made yesterday regarding China-related matters.

Mao said that fostering healthy and stable China-South Korea relations aligns with the common interests of both nations, expressing hope that South Korea will actively contribute to this goal.

China has capabilities, conditions to contain 'Taiwan Independence' separatist acts: former deputy director of Association for Relations across Taiwan Straits

The Global Times Annual Conference 2025, themed, "Moving forward in Partnership: Resonance of Values between China and the World," is held in Beijing on Saturday. During a discussion on the topic "Exploring the Way of Interaction among Major Powers: Differences and Consensus," Wang Zaixi, former deputy director of Association for Relations across the Taiwan Straits, said that on the Taiwan question, China's policy is very clear. "That is to continue to strive for peaceful reunification, while also making full preparations for the dangerous move made by 'Taiwan independence' separatists," he said.

Wang Zaixi said that in the past four years, the Biden administration had a characteristic in handling China-US relations. "On the one hand, it adopted a comprehensive tough containment strategy toward China; on the other hand, it had always maintained close contacts with the Chinese government's senior officials, including the military communication." 

 "In their own words, they aimed to ensure that the two countries' relations would avoid confrontation in the process of competition. Therefore, in these four years, China-US relations were sometimes rather tense, but generally controllable. After the new US administration takes office, it is generally believed that the US side may intensify its efforts in containing China," Wang said. "In my opinion, there are still areas and room for cooperation in China-US relations," Wang noted. 

One of the core matters in China-US relations is the Taiwan question, he said. "There is uncertainty about the US side's policy on this question in the future. However, on the Taiwan question, China has dominance. The US will have great concerns even if it plans to interference in the Taiwan question. The Democratic Progressive Party (DPP) authorities in Taiwan do want to "rely on the US to seek independence" and "seek independence through military means," but they are doomed to failure, Wang stressed. 

 "After decades of development, especially in the past dozen years with the enhancement of China's comprehensive national strength, especially its military strength, China has capabilities and conditions to contain 'Taiwan independence' separatist acts," Wang said during the conference.