Jilin, 3 March (ZXS) -- How to open the genetic code of "extraterrestrial visitors" in Jilin?
——Interview with Fu Ying, director of the meteorite department of Jilin City (Meteorite) Museum
China News Agency reporter Cang Yan Shi Hongyu
Meteorites are rock samples that fall to the ground through the atmosphere of extraterrestrial fragments, and are also precious physical specimens for human direct cognition of solar system objects. On March 1976, 3, the world's largest stony meteorite rain so far fell on the plain of more than 8 square kilometers in Jilin, including 500 large meteorites.
After these "extraterrestrial visitors" landed, Chinese and foreign scholars extensively participated in the research of Jilin meteorites, which achieved fruitful results and laid the foundation for China's subsequent deep space exploration. Recently, Fu Ying, director of the meteorite department of Jilin City (Meteorite) Museum, accepted an exclusive interview with China News Agency's "East-West Question" to interpret the secrets discovered by Chinese and foreign scientists from Jilin meteorites.
Video: How to open the genetic code of "aliens" in Jilin? Source: China News Network
The following is a summary of the interview:
China News Agency: Can you introduce the landing process of the Jilin meteorite?
Fu Ying: Jilin meteorites come from the asteroid belt. According to the mechanical analysis of the fall process and the study of orbits in the atmosphere, the asteroid had a diameter of about 1.7 meters, weighed about 4 tons, and was nearly spherical before entering the Earth's atmosphere. It caught up with the Earth almost along the Earth's orbit from the back of the Earth at 1976:3 on March 8, 15, and entered the atmosphere from east to west, with a surface temperature of about 2000 °C-3000 °C when passing through the atmosphere.
According to the recollections of witnesses, at that time, a large fireball was seen roaring from the northeast of the sky, and it burst out by the impact of the high temperature and high pressure air flow, which burst at an altitude of 19 kilometers above the ground, forming countless small fireballs, scattered in a rain shape to form the Jilin meteorite rain, and the most massive fragments fell in the front.
A crater formed when the Jilin No. 1 meteorite collides with the ground. Photo courtesy of Jilin Meteorite Museum
The landing of meteorites is accidental and random. In northern China, in March, when the weather had just warmed up, meteorite No. 1 fell on Shishe, a mountain village in Birch Factory Town, Yongji County, Jilin City, penetrating 7.6 meters of frozen soil and escaping 5.2 meters underground, with a diameter of 1.50 meters. According to eyewitness recollections, the meteorite exploded after it landed, and from a distance, the tumbling smoke gradually formed a small mushroom cloud, about 150 meters high, with a huge concentration of soot. The splashed clumps of earth reached a distance of more than <> meters.
The earthquake caused by the Jilin No. 1 meteorite was equivalent to a magnitude 7.1976 earthquake, and this shock wave was recorded by seismic stations in Jilin City and Fengman District, giving the Jilin meteorite rain an accurate time record: 3:8:15 on March 2, 36. The Jilin No. <> meteorite has also become the largest stone meteorite in the world.
Jilin No. 1 meteorite in the collection of Jilin Meteorite Museum. Photo by Cangyan
China News Agency: Jilin meteorite has become a medium for scientific exchanges between China and foreign countries, what exchanges and research have scientific research institutions around the world carried out?
Fu Ying: Jilin meteorite is an archaeological sample of the solar system, with a relatively complex history of cosmic ray irradiation, rich scientific connotation, which has aroused great interest and attention from the international meteorite research community. Following the principle of equality, mutual benefit and win-win cooperation, China has donated Jilin meteorite samples to more than 12 laboratories in 40 countries, including the Max Planck Society in Germany, the University of California, and the Japan Polar Research Institute, and scientific research is carried out all over the world. Scholars determined the cosmogenesis of the samples and found that the composition of noble gas isotopes in the dark and light phases of the Jilin meteorite was quite different, and the exposure age of the universe was about 100 million years.
The joint expedition team of the Chinese Academy of Sciences conducted the first systematic meteorite scientific expedition in New China. Chinese scientists represented by Academician Ouyang Ziyuan have obtained extremely rich scientific information through on-site investigation and multidisciplinary comprehensive research, involving the origin and evolution of the solar system, the origin of life, cosmic rays and material interactions, the process of planet formation, the evolution of asteroids, the irradiation history of interplanetary space and the physical and chemical environment of meteorite landing process.
Jilin No. 1 meteorite excavation site. Photo courtesy of Jilin Meteorite Museum
It can be said that Jilin meteorite is a rare physical material for the study of celestial evolution, the origin of life, the origin of elements, space technology and many other disciplines, and is an extremely precious archaeological specimen of the universe. The research results of the Jilin meteorite are also recognized as examples of extraterrestrial material research. Through the study of Jilin meteorites, China has gradually formed a multidisciplinary scientific research team in meteoritics, cosmic chemistry and space geology that can conduct comprehensive research.
Except for a very small number of Jilin meteorites used for scientific research and other purposes, most of them are preserved in the Jilin City (Meteorite) Museum. At present, meteorite specimens collected around the world can be divided into stony meteorites, stony iron meteorites, and iron meteorites according to the different chemical compositions they contain. Jilin City (Meteorite) Museum exchanged Jilin meteorites for more than 40 kinds of meteorites at home and abroad, including Allende meteorite in Mexico, Sikhote-Alin iron meteorite in Russia, Gibeon meteorite in Namibia, etc., further enriching scientific research samples and content.
Meteorites in the collection of the Jilin Meteorite Museum. Photo by Cangyan
China News Agency: In ancient and modern China and abroad, human exploration of the universe has never stopped, what do you think is the significance and future direction of meteorite research, and what help may it provide for human exploration of the earth and outer space?
Fu Ying: The ancient Chinese noticed meteors and meteorites very early. More than 2000,<> years ago, the "Bamboo Book Chronicle" written by the Spring and Autumn Warring States historian recorded "Ten years of the emperor's reign, five stars were wrong, and meteorites were like rain at night", recording a meteorite rain that occurred in the Xia Dynasty. In addition, the Han Dynasty historian Sima Qian defined in the "Shiji": "When a star falls to the ground, then Shiye." ”
Fu Ying tells how to open the genetic code of "extraterrestrial visitors". Photo by Cangyan
Although humans have recorded and collected meteorites for a long time, meteorites as a science are only more than 200 years old. The most important thing is the scientific research value of meteorites, and scientists from various countries have found more than 4,<> meteorites in the Antarctic ice sheet region, which are mainly used for scientific research and popular science education. Compared with planetary landings and asteroid surface sampling, meteorites are studied with low cost and wide representativeness. Specifically, the research value of meteorites is reflected in the following aspects.
First, meteorites are outer space rocks, but also space fossils. The composition of meteorites reflects the changes that have occurred in their parent bodies, and studying its formation and evolution is of great significance for understanding the early evolution of the solar system, and can provide a comparative standard for the evolution of planets after the formation of the solar system.
Second, meteorites are homologous to Earth. At present, it has been determined that the age of meteorites is very similar to that of the Earth, and the period of their formation of independent cosmic bodies is roughly the same, and the known chemical elements on Earth have also been found in meteorites. Studying the chemical composition and chemical evolution of asteroids through meteorites is of great help to understanding the origin and evolution of the Earth.
Third, in recent years, human beings have become more and more aware that the earth is in danger of being hit by asteroids, and through the study of asteroids and meteorites, it can help carry out asteroid exploration programs, research, monitoring, early warning and defense against asteroid impacts, and protect the earth's home.
Ouyang Ziyuan (second from left) and foreign experts study Jilin meteorites. Photo courtesy of Jilin Meteorite Museum
China News Agency: At present, there are tens of thousands of "extraterrestrial visitors" around the world, outside the academic circle, how do "star friends" from different countries communicate, and what is the role of Jilin meteorites?
Fu Ying: Meteorites have important scientific value and are a scarce resource. For most people, it is a star in the sky, a gift from heaven, with a good meaning. At the same time, some meteorites have a beautiful appearance and are collectibles for odd stone lovers.
In the late 20s of the 90th century, a large number of meteorites were discovered in the African tropical desert, and then meteorites emerged as commodities at trade fairs and on the Internet, providing samples for scientific research on the one hand, and on the other hand, bringing opportunities for meteorite collectors from all over the world. Chinese meteorite collections started late, but developed quickly.
Scientific research institutions and museums around the country publicize and popularize meteorite knowledge, so that enthusiasts' awareness of meteorites is constantly improving. Taking Jilin City as an example, in recent years, the Jilin City (Meteorite) Museum has carried out a series of general exchange activities between Chinese and surgical personnel using Jilin meteorite as the medium to promote close exchanges between meteorite researchers and "star friends" from different countries.
"Star Friends" filmed the "starry sky" in the museum. Photo by Cangyan
In 2018, the China Jilin International Meteorite Expo, co-hosted by the Jilin Municipal People's Government, the International Meteorite Society and the Purple Mountain Observatory of the Chinese Academy of Sciences, and undertaken by the Jilin (Meteorite) Museum, attracted extensive participation from international meteorite experts and domestic meteorite collectors and promoted meteorite science.
Today, with the increasing progress of society and the popularization of science, the public has a deeper and deeper understanding of the scientific value of Jilin meteorite. The series of popular science activities carried out by Jilin meteorite has become a professional, academic and authoritative meteorite exchange platform, and a bridge connecting meteorite researchers, science popularization workers and star friends. (End)
Respondent Profile:
Fu Ying, Master of Archaeology and Museology from Jilin University, is currently the director of the meteorite department of Jilin Museum, an associate researcher of Wenbo, and the executive deputy editor of Jilin Museum Journal. He has long been engaged in meteorite exhibition planning, meteorite protection research, meteorite laboratory science popularization activity planning, meteorite micro-classroom planning and other work. The popular science research course "Exploring Interstellar and Touching Meteorites" presided over and planned won the "2015-2019 National Museum Nature and Science and Technology Excellent Research Course", and the paper "Research on Museum Research Travel from the Perspective of Public Cultural Service in the New Era" won the first prize of the "<>th Paper Seminar of Jilin Provincial Museum Association".