Initial results of Chang'e-6's lunar samples show differences between front and back – World –

The samples returned to Earth by the Chang'e-6 mission have a much lower density on the Earth-facing side than those from the previous Chang'e-5 mission, scientists wrote in a Chinese-language National Science Review report. Based on the grain size, the researchers also assume that the soil composition is different.

According to experts, the sample contained different types of rocks such as basalt found locally on the moon, which proves the history of volcanic activity on Earth's satellite. However, other non-volcanic rocks from the sample are likely to provide information about the impact in the crater where the sample was taken, as well as about the lunar crust.

Looking at the chemical composition, the researchers found some differences compared to samples taken from the Earth-facing side of the Moon. According to the scientific paper, the rock from the far side of the Moon was relatively rich in aluminum oxide (14 percent) and calcium oxide (12 percent). On the other hand, the proportion of iron (II) oxide was 17 percent, which is lower than in the front. Trace elements such as potassium and rare earths were also present in the sample in significantly lower concentrations.

In late June, Chang'e-6 successfully brought back rock samples from the far side of the moon to Earth for the first time in human history after a technically very complex mission. The probe excavated a 1,935.3-gram sample from the South Pole-Aitken Basin, the largest impact crater. Scientists hope the samples will provide, among other things, conclusions about the composition of the moon, its crust, and differences in volcanic activity on both sides of the moon. Missions from other countries have also taken soil samples from the moon, but only from the more accessible side facing Earth.