Chinese researchers have studied the lunar samples brought back by the Chang'e-5 mission. Their results suggested that the samples are a new type of lunar basalt, different from those collected during previous Apollo and Luna missions, and dated the youngest rock on the Moon at around 2 billion years in age, extending the "life" of lunar volcanism 800-900 million years longer than previously known.
The studies, conducted mainly by a research team at the Institute of Geology and Geophysics (IGG) and National Astronomical Observatories (NAOC) of the Chinese Academy of Sciences (CAS), was published in Nature entitled "Two-billion-year-old volcanism on the Moon from Chang’e-5 basalts", "Two-billion-year-old volcanism on the Moon from Chang’e-5 basalts", "Non-KREEP origin for Chang’e-5 basalts in the Procellarum KREEP Terrane" and "A dry lunar mantle reservoir for young mare basalts of Chang’e-5" and in National Science Review.
These samples of volcanic rock, which is a type of basalt, are the youngest lunar samples to be directly dated, at around 2 billion years old. Analysis of these basalts reveal how the composition and water content of the Moon changed over time, which may help us to understand the geological and geochemical evolution of the Moon, according to the IGG study.
NAOC researchers analyzed rock particles 10 to 500 microns (a quarter the thickness of a credit card) in size, and discovered that their characteristics were mainly those of basalt. But unlike the magnesium and iron-rich basalt found on Earth, lunar basalt is low in magnesium and high in iron oxide.