Mantle found on the back side of the moon

The first-ever concrete piece of evidence for mantle on the moon, just like the Earth, was found. The mantle is a layer of rock inside a planetary body right below a crust, surrounding a metal core. This is the first outcome produced by China’s Chang’e-4, an unmanned lunar probe, which has successfully landed on the far side of the moon on January 3 for the first time in human history. This represents a big step forward for humans to understand the origin and early conditions of the moon and the process of planetary formation.

A team at the Chinese Academy of Sciences led by Dr. Li Chunlai published a paper on Nature on Thursday, which included the analysis of the exploration findings obtained using Yutu-2 rover’s visible and near infrared spectrometer. The paper concluded that there are olivine and pyroxene, which are low in calcium and high in iron and magnesium, in the South Pole–Aitken Basin of the moon. This is the result of comparative analysis between data collected by Yutu-2 and general substances found on the moon’s surface.

Moon rocks have been brought back to the Earth before, but this is the first time a rover directly explores and analyzes minerals in a 13 kilometer-deep crater. “Low-calcium olivine and pyroxene are thought to make up the lunar mantle,” the research team said. “Understanding the composition of the lunar mantle is key to understanding not only the structure of the moon’s mantle but also how the moon formed and evolved.”


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