Researchers analysed lunar soil brought back by China’s Chang’e-6 spacecraft confirmed that billions of years ago, volcanoes erupted on the mysterious back side of the moon, just like the side in view.
The study by two separate teams found fragments of volcanic rock about 2.8 billion years old. The other fragment was even older, with an age of 4.2 billion years. Obtaining the samples was significant as scientists have no other data on the area, said Christopher Hamilton, an expert on planetary volcanoes at the University of Arizona, who was not involved in the study.
Previous studies, including data from NASA’s Lunar Reconnaissance Orbiter, have suggested that the far side may also have a volcanic past. The first samples from this Earth-facing region confirm an active history.
The back side of the moon is mottled with craters and has fewer flat, dark plains carved by lava flows than the near side. Why the two halves are so different remains a mystery, says study co-author Qiu-Li Li of the Chinese Academy of Sciences. The new results show more than 1 billion years of volcanic eruptions on the back side of the moon, according to him. Future studies will determine how the activity continued for so long.
China has launched several spacecraft to the moon. In 2020, the Chang’e-5 spacecraft returned lunar rocks from the near side. The Chang’e-4 spacecraft became the first to visit the back side of the moon in 2019. Meanwhile, Chang’e-6 became the first spacecraft to return with a cargo of rocks and soil from the little-studied far side of the moon.
