BEIJING, Oct. 8 (Xinhua) -- Researchers have studied the lunar samples brought back by the Chang'e-5 mission and found that they are likely around 1.96 billion years old, shedding new light on the evolution of the moon, said the China National Space Administration (CNSA) Friday.
The first research article on the Chang'e-5 samples, titled "Age and composition of young basalts on the Moon, measured from samples returned by Chang'e-5," was published online in the journal Science Friday. It was authored by researchers from the Institute of Geology, Chinese Academy of Geological Sciences, and other international institutions.
The article said China's Chang'e-5 probe touched down on the Oceanus Procellarum region of the moon, which hosts high concentrations of elements that generate heat through long-lived radioactive decay and may have sustained prolonged magmatic activity on the near side of the Moon.
Orbital data indicate that the basalt lavas in Oceanus Procellarum are the youngest volcanic units on the Moon. The Chang'e-5 probe collected samples of these lunar basalt lavas and brought them to Earth.
The researchers analyzed two fragments from the Chang'e-5 samples and found minerals common in lunar basalts, such as chemically zoned clinopyroxene, plagioclase, olivine, and ilmenite, with small amounts of quartz and cristobalite.
The study proved that the moon still had magmatic activity 1.96 billion years ago, providing key evidence for the study of the evolution of the moon, said the CNSA.
When the moon's magmatic activity stopped is one of the major issues in its evolutionary history. Previous research on lunar samples has not found any magmatic activity younger than 2.9 billion years on the moon.
On July 12, 2021, China delivered about 17 grams of lunar samples brought back by the Chang'e-5 probe to 13 institutions, which had submitted applications to the Lunar Exploration and Space Program Center of the CNSA to utilize the samples for research purposes.
The Chang'e-5 probe, comprising an orbiter, a lander, an ascender, and a returner, was launched on Nov. 24, 2020. The return capsule landed in north China's Inner Mongolia Autonomous Region on Dec. 17, retrieving about 1,731 grams of moon samples. Enditem