[Explanation] The reporter learned from China University of Geosciences (Wuhan) on July 7 that the team led by Professor Wang Zaicong and Zong Keqing found that the chemical composition of the Chang'e 5 lunar soil and the young basalt in the landing area were highly consistent based on the analysis of geochemical elements. , and suggested that the Chang'e-5 young basalt may originate from the lunar mantle source region rich in clinopyroxene and containing a small amount of Krep material.
[Explanation] Wang Zaicong said that the chemical composition of the Chang'e 5 lunar soil (except for nickel and other individual elements) can be used to represent the average chemical composition of the young basalt of the lunar sea in the landing area.
This provides a new way to study the origin of young lunar basalts through lunar soil, and then to understand the internal evolution of the moon.
[Concurrent] Wang Zaicong, Professor of the Department of Geochemistry, China University of Geosciences (Wuhan)
The lunar (soil) sample we obtained this time was the first batch of Chang'e 5 lunar soil obtained in July last summer (2021), and then we took these lunar soils to the laboratory for an analysis of chemical composition.
A chemical composition of lunar soil can represent the composition of the Chang'e 5 basalt, so that we can further understand the origin and evolution of basalt through the composition of basalt.
[Explanation] In July 2021, Wang Zaicong's team applied to take 200 mg of lunar soil samples from the first batch of Chang'e 5.
The team established a new analysis technique for lunar soil samples. With a very low loss of 2 mg of samples, the content of 48 major and trace elements in the lunar soil was accurately determined at the same time, and it was found that the Chang'e-5 surface collected lunar soil. The chemical composition is very uniform at the milligram level.
[Concurrent] Professor Zong Keqing, Department of Geochemistry, China University of Geosciences (Wuhan)
Our Chang'e 5 retrieved samples are very precious.
So we need to use the minimum consumption to obtain more composition of one element.
So in this study, we developed a composition that simultaneously obtained 48 major and trace elements with very little sample consumption, with at least two milligrams of sample consumed.
By using the composition of these trace elements, we can well reflect some of the moon, and we say some processes of its formation and evolution.
We ran those two batches of samples three times, and then we got a total of 7 data analyses, and then we proved that the composition of these lunar soils is very, very uniform at the milligram level.
[Explanation] The data show that, except for nickel, the content of major and trace elements in the Chang'e-5 lunar soil is highly consistent with the element content of basalt glass and debris.
This result shows that in the lunar sea area in the northern part of the Ocean of Storms, where the landing area of Chang'e-5 is located, the impact of other materials is very limited.
Wang Zaicong introduced that the nickel content of lunar basalts is much lower than that of meteorites, but the Chang'e-5 lunar soil has the characteristics of high nickel content, indicating that meteorite material is added to the lunar soil.
[Concurrent] Wang Zaicong, Professor of the Department of Geochemistry, China University of Geosciences (Wuhan)
We found that the content of nickel in the lunar soil of Chang'e 5 is relatively high, which means that it has foreign meteorite additions, and then we accurately calculated its content, and the amount of meteorites that may be added is about 1%.
[Explanation] According to reports, the above results systematically evaluated the chemical composition of the Chang'e-5 lunar soil, and quantitatively analyzed the amount of foreign substances mixed in the lunar soil, which provided a new perspective for understanding the lunar young magma activities and the later transformation process.
Reporter Zheng Ziyan reports from Wuhan, Hubei
Responsible editor: [Luo Pan]