Chang'e -4 completed the 44th day work

Chang'e -4 mission "Yutu II" lunar vehicle and landing instruments completed the dormant settings at 19:14 and July 6, July 6, and completed the day of the 44th day of the day, and entered the night of the night of the night. The lunar car has a total mileage of 1239.88 meters on the back of the moon.

Chang'e-4 research results revealed Antarctica-Aiken Basin

Cause of ingredients

The Antarctic-Aiken Basin is the largest impact basin on the moon, with a diameter of more than 2400 kilometers. Studying Antarctica-Aiken Basin is of great significance to reveal the origin of the moon's asymmetric, impact process, early evolution process, and deep material components. The orbit remote sensing observation shows that there is an ingredients in the center of the Antarctic-Aiken Basin, and the planet science team of Shandong University can see near-infrared spectrum data analysis and interpretation of the in situ of Yutu II. The main source of substances provides important constraints for the detection of the Antarctic Basin and even the deep moon in the future.

The main material components on the moon surface are pyroxyl and olives. The material components at the bottom of the Antarctic-Aiken Basin are abnormal. The content of magnesium iron silicate minerals and iron content are significantly higher than the peripheral area of ​​the basin (Figure 1).

Figure 1. The content distribution of iron and pyroxophytic content inside and outside the Antarctic-Aikan basin

In the past, the research on the material composition of the Antarctic-Aiken Basin only focused on magnesium iron minerals. Due to the characteristics of magnesium and iron abnormalities in this area, it even triggered a debate about whether the lunar mantle was olive or pyroneite. Although according to the lunar magma ocean hypothesis, olives and pyroxyl are the main minerals of the moon curtain, but the deep -forming magma invasion after the formation of the moon shell can also form a rock rich in olivine or pyroe in the moon shell, so it is rich in olives Or pyroxin cannot be used as evidence from the moon curtain. So far, human beings have not obtained the sample of the Antarctic-Aiken Basin to return to the earth, and they cannot know its trace elements and isotope characteristics. In the remote sensing or in-situ detection, the obtained material component information is also distinguished from the sources of the shell and the source of the veil source rocks. Key indicators.

Findson's collapse of the Antarctic-Aiken ingredients abnormal area of ​​the material zone exceeds the content of oblique long stone content that can be evolved in the process of impact melting. Therefore The addition of moon shell substances (Figure 2). Numerical simulation research believes that during the Antarctic-Aiken impact excavation process, the moon shell has been completely peeled, but in the subsequent transformation stage, the collapse of the instantaneous pit wall may cause the moon shell material to slide the bottom of the basin. In addition, the impact of other basins after the Antarctic-Aiken impact incident also produced a backfilling effect on the bottom of the Antarctic-Aiken Basin. The moon curtain or impact melting product exposed during the formation of the basin is likely to be diluted by the moon shell material. The results of mineral and glutinous chemical solution analysis show that the surface moon soil on the surface of the ingredients is made of about 70%of the monthly shell material mixed with about 30%of the impact elements.

Figure 2. Minerals and sources of Chang'e -4 landing area and its source repository

The first author of the research results is Chen Jian, a postdoctoral University of Shandong University. The author of the communications is the head of the Star Science Team of Shandong University. Professor Ling Zongcheng, a senior researcher at the Outstanding Innovation Center of the Chinese Academy of Sciences, published in the international astronomical journal "The Astrophysical Journal Letters".

Original link:

https://iopScience.iop.org/article/10.3847/2041-8213/ac6e6c

Source: China Lunar Exploration Project

Text: Chen Jian Shi Meng Qi Tielei

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