How much is the stone on the moon

　　At 10:26 on January 3, 2019, China’s “Chang’e 4” detector landed autonomously in the von Carmen impact crater in the Antarctic basin of the Antarctic on the back of the moon, achieving the first soft landing of the human detector on the back of the moon.
　　Why go to the back of the moon?
　　Because the radiation interference on the back of the moon is minimal, it is conducive to carrying out scientific research, and the value of research is higher than the positive. The back side of the moon is different from the frontal geological structure. The oldest moon shell rocks are preserved here, which is conducive to studying the early history of the moon and the earth.
　　It can be seen from the pictures passed back that the moon is covered with rocks. If you happen to have a stone on the moon, how much do you think it is worth? Speaking of it, you may not believe that, at the end of 2018, the world’s famous Sotheby’s auction company sold three pieces of moon rock fragments, and the transaction price was as high as 855,000 US dollars (about 5.8 million yuan).
　　Don’t look at it as just a small rock fragment, but it comes from the far moon, so it is understandable even if it’s valuable. In fact, since humans have landed on the moon, astronauts have collected too few samples of lunar rocks. The three lunar rocks in this auction were obtained by the unmanned probe in the Soviet Lunar-16 mission in 1970, and the actual mass was only about 200 mg. So, how many moon rocks are there in human hands? The Apollo mission collected 2,200 samples and weighed 382 kilograms; Lunar-16, Lunar-20, and Lunar-24 missions brought back to Earth a total of 301 grams of lunar rock samples; a total of more than 300 lunar meteorites fell to the earth. About 190 kg. In this way, the moon rocks add up to more than half a ton.
　　Since there are more than half a ton of moon rocks, these three small rock fragments can still be sold at a high price. Why is it so valuable? Because those half tons of moon rocks are protected by the state, it is impossible to sell them. Therefore, these three rock fragments are valuable. These three pieces of lunar rock are the “commemorative medal” awarded by the Soviet government to the widow of Sergei Pavlovich Korolev, director of the Soviet Union’s space program. This is also the first privately-owned moon rock in human history.
　　The vast majority of other lunar rocks are kept in the laboratory for lunar research. Apollo 17 astronauts Eugene Cernan and Harrison Schmidt collected a rock made of many fragments in the Taurus Valley at the end of their third and final lunar walk. These fragments have different sizes and shapes, most likely from different areas of the moon. Later, US President Nixon issued an order in 1973 to distribute this rock fragment to 50 states in the United States and to give it to 135 friendly countries as a national gift. The fragments were installed in an acrylic sphere and mounted on wooden boards with the national flag of the receiving country.
　　The moon rocks distributed in this batch are called “Friendly Moon Rocks” and a total of 270 were sent out. However, as of now, about 180 rocks have fallen unknown. Because these “friendly lunar rocks” are public gifts donated publicly by national organizations, they are not allowed to be traded under US law, so only these three pieces of lunar rock fragments can be sold for auction.
　　In fact, these three pieces of lunar rock fragments have not been auctioned for the first time. In 1993, at this Sotheby’s auction house, a mysterious American collector spent 443,500 US dollars (about 3 million yuan) to buy it from the Russians. After a lapse of 25 years, in December 2018, the collector may have anticipated that these three pieces of moon rock may depreciate, so he quickly cleared the deal and auctioned out $ 855,000, which was close to twice the starting price.
　　From the sky-high price of three pieces of lunar rock, we can see how valuable lunar rocks are. At the same time, we can also see how much humans yearn for everything on the moon.