A team of geologists at the Chinese Academy of Geological Sciences, the Institute of Space Sciences and the Shandong Institute of Geological Sciences, all in China, has found evidence in soil samples collected from the far side of the moon that bolsters a theory that the moon was once covered by an ocean of magma. In their study published in the journal Science, the group analyzed a moon soil sample returned to Earth by China’s Chang’e-6 mission.

In 2024, the China National Space Administration launched a spacecraft that carried a lander to the surface of the far side of the moon. The mission was the first to collect samples from the far side of the moon and return them to the Earth. For this new study, the research team obtained 2 grams of the soil for testing.

The researchers used multiple methods to determine its composition and then compared the results to those of analyses of soil samples from the near side of the moon.