Chinese spacecraft rewrites the geological history of the Moon

Rock samples collected by the Chang'e 5 spacecraft reveal volcanic activity on the Moon lasting nearly a billion years longer than previously thought.

After months of research since China 's Chang'e 5 probe returned to Earth with 2kg of lunar soil samples late last year, geologists have made some important discoveries about the satellite. Earth's only natural.

In a report published in the journal Nature in October, a team from the Institute of Geology and Geophysics (IGG) of the Chinese Academy of Sciences (CAS) said they had identified young volcanic rock samples. the largest on the Moon, about 2 billion years, thereby extending the "life" of the Moon's volcanoes by 800-900 million years than previously thought.

Before Thuong Nga 5, the last time humans successfully brought Moon rock samples back to Earth was 4 decades ago during NASA's Apollo 17 mission. Subsequent analysis of the sample revealed that the youngest volcanic rock - the last sign of volcanism on the Moon - was nearly three billion years old.

"The most obvious difference between the samples from Chang'e 5 and Apollo is their age. This extends the duration of volcanic activity on the Moon by almost 1 billion years," said Professor Ross Mitchell at IGG strong.

The Chang'e 5 spacecraft collected the Moon rock and brought it back to Earth. (Video: Reuters)

The Chinese specimens were collected at a basalt site called "Oceanus Procellarum". This area formed during volcanic eruptions billions of years ago. That means the surface rock originally originated from the interior of the Moon as ancient magma.

The new discovery raises more questions. Compared to Earth, the Moon is much smaller and lighter. It has no atmosphere and the magnetic field is almost non-existent. How can a celestial body retain heat for so long? It should have cooled down a lot sooner.

The team thinks that radioactive elements discovered inside the Moon's topsoil could be the answer. They provided a lot of heat to the Moon, allowing the mantle to melt much more easily. These radioactive substances are collectively known as "KREEP" , an acronym for a mixture of potassium (K), rare earth elements (REE) and phosphorus (P) - a distinctive geochemical composition of some Moon rock.

"From orbital observations, we know that there are a lot of heat-generating elements at the Moon's surface . But the question is whether it has the same amount of heat-generating elements in the mantle? Because that's what it is?" where celestial bodies need to melt the mantle to create volcanoes. The rocks on the surface are rich in these heat-producing elements, but when they get down to the mantle, they're rare," added Mitchell.

Another theory is water, the source of all life. Scientists say a lot of water may have been trapped in the Moon's mantle since ancient times.

The Chinese spacecraft is carrying out sampling on the Moon.

"If you add water to a rock, it usually melts at a much lower temperature than if there was no water in it," explains Mitchell. "There are some measurements from the Apollo era, where the Moon's mantle has as much water as the Earth's mantle, but there are other measurements that show some places much drier. So the rock sample Mitchell collected. Which type? Wet or dry?".

Analysis shows that the basalt sample of Thuong Nga 5 has very low moisture content, so the mantle in this area did not contain much water at the time the rock was formed.

So what exactly makes the Moon retain heat for so long? This has not yet been discovered by scientists. "That's the most interesting thing about the mission Chang'e 5. When you answer a question, a new question will appear , " said the Professor.