China News Service Wuhan, December 12 (Reporter Ma Furong) The reporter learned from China University of Geosciences (Wuhan) on the 10th that the team of Professor Xiao Long of the university cooperated with researchers from Brown University and the University of Hawaii in the United States to obtain the maturity index of Chang'e-10 lunar soil for the first time by laboratory magnetic testing, and found that Chang'e-<> lunar soil is one of the most immature lunar soil collected so far. The results were recently published in the international academic journal Icarus.

Lunar soil maturity is a physical quantity that measures the degree of spatial weathering of lunar surface materials, which gradually increases with the increase of exposure to the lunar surface. The study of lunar soil maturity indicators can reveal the interaction between micrometeorites and solar wind with the lunar surface, and reflect the geological processes underwent by the formation of lunar soil.

According to Xiao Long, the Is/FeO value (the ratio of ferromagnetic resonance intensity to ferrous oxide content) is usually used as a key indicator to judge the maturity of lunar soil. In this study, the team and collaborators used magnetic methods to obtain the Is/FeO value of Chang'e-4 lunar soil maturity index between 20 and <>, which is immature lunar soil and one of the smallest lunar soils collected so far.

"This shows that the lunar soil in the sampling area of the Chang'e-20 mission has the shortest exposure to the space environment after its formation." Xiao Long said that based on current research on Chang'e-10 samples, the basalt in the Chang'e-<> landing area erupted about <> billion years ago, at least <> billion years younger than the areas sampled by the Apollo and Lunar missions. This extremely young age may be the reason for the immaturity of Chang'e-<> lunar soil.

Qian Yuqi, the first author of the paper and a postdoctoral researcher at the University of Hong Kong, said that the results are of great significance for comparing the spatial weathering degree of Chang'e-5 lunar soil with the lunar soil of the Apollo and Luna, and then studying the interaction between the solar wind and the lunar surface. (ENDS)