Please check the “express” from the moon

1 gram of lunar soil, a lot of articles
In the 1960s and 1970s, the United States implemented six manned moon landings through the Apollo program, bringing back 381.7 kilograms of lunar samples. For more than half a century, Chinese scientists have been tracking the research progress of lunar samples for a long time. In the early 1970s, Chinese scientists used 0.5 gram of the 1 gram of moon rock gifted to China by the United States for comprehensive research and formed a preliminary understanding and understanding of the moon. Although the lunar soil samples collected by Chang’e 5 are the first time that Chinese have independently obtained lunar samples, the study of the moon has already laid a solid foundation for it. Chinese scientists will then conduct micro-area, micro-beam, and micro-analysis of the samples. The results of the analysis can be compared with lunar samples and lunar meteorites collected from other regions, and can also verify the results of remote sensing detection.

Go around, fall, and return to the perfect ending
After 17 years of continuous efforts, the lunar exploration project launched in 2004 has successfully completed the three-step mission of winding, landing, and returning. The Chang’e No. 1 and No. 2 missions completed the remote sensing detection of the whole moon; the Chang’e No. 3 and No. 4 missions realized the landing detection of key areas and the inspection and survey of the lunar rover. In particular, the Chang’e No. 4 realized the realization of human history. The spacecraft landed on the back of the moon for the first time. The lunar samples recovered by Chang’e-5 marked the successful conclusion of the lunar exploration project. At the same time, the mission of the second phase of exploration, landing, and stationing was started-preparing for the construction of a lunar research station and manned landing on the moon.

Compared with the earth’s soil, the lunar soil is the rock on the moon’s surface, formed after tens of millions to hundreds of millions of years of weathering in space. Due to the small mass of the moon, it cannot “catch” the air, so the surface of the moon is an ultra-high vacuum environment. The lunar soil created by frequent collisions of small celestial bodies and micrometeorites, severe temperature difference between day and night, solar wind and long-term bombardment of cosmic rays, has not experienced the dissolution of water, the oxidation of oxygen, and the effects of organisms that are common on the earth. It is very different. In the earth’s soil. The lunar soil has no clay minerals, no organic matter, and most of the minerals and elements are in a reduced state. Therefore, to make full use of the scientific value of lunar samples, we must first prevent the lunar soil from coming into contact with oxygen-containing air, microorganisms, and water vapor. It is necessary to keep the lunar samples properly with high-purity nitrogen in a closed environment to avoid the pollution of the earth environment.

Is 1731 grams of lunar soil enough?
You may ask, is the 1,731 grams of lunar soil and rock samples brought back by Chang’e 5 a little less? In fact, for lunar samples, how much is not a problem. It is more important to take diversified soils from different areas on the moon, because lunar soils in different areas contain different information.

The lunar samples collected by the American Apollo plan came from 6 lunar landing sites, and the lunar samples collected by the former Soviet Union came from 3 lunar landing sites. However, the surface area of ​​the moon is about 3,800 square kilometers. The samples from these locations alone cannot represent the moon. Full picture. The US Apollo plan to land on the moon is located in the low and middle latitudes on both sides of the Moon’s equator, known as the Apollo Belt. The sampling point of the former Soviet Union is on the east side of the front of the moon.

This time, the sampling point of Chang’e-5 is in the northwest of the front of the moon. This is the largest moon sea on the moon-the ocean of storms. Human probes have never landed before. It is very far from the Apollo moon landing site and the sampling site of the former Soviet Union. The geological background is obviously different. Moreover, remote sensing research results show that the volcanic activity at the Chang’e-5 sampling site stopped very late, and it is possible to discover young magmatic rocks, which helps to understand when the internal energy of the moon is exhausted.

Through the study of lunar samples, one can understand the current state of the moon, understand the evolutionary history of the moon, and uncover the mystery of the origin of the moon. At the same time, it will also revise our knowledge of the solar system and the Earth-Moon system.

1731 grams of lunar soil is not only an important object of scientific research, but also an important carrier for popular science and science education for young people. As the third country in the world to collect lunar samples, the fact that Chang’e 5 retrieved the lunar soil itself is the best manifestation of a country’s comprehensive capabilities. It is hoped that the general public, especially young students, can learn about the progress of earth and planetary science, astronomy and space technology behind the samples through contact with lunar samples, and then pay attention to science and technology, support and participate in the national scientific and technological innovation.