Li Bai, a great poet of China's Tang Dynasty, has a famous poem: "When you don't know the moon, call it a white jade disk", in the eyes of ordinary people on the earth, the moon is always clean and beautiful, it has a wonderful yin and sunny circle, emitting a non-dazzling light, becoming the most obvious celestial body we can see in the night.
Until we have a basic understanding of astronomy, we don't know what kind of "object" the moon is, and we will even imagine that there are gods living on it and osmanthus trees. For human beings, the regular changes of the moon are an important reference for our timing, and almost every culture uses the phases of the moon to time. After the development of modern astronomy, we also understand what kind of celestial body the moon is, and how those clouds and clouds were born.
Unlike the "Guanghan Palace" we imagined, after removing the reflection of sunlight, after a close look at the moon, we will find that the moon is not bright nor smooth, it is a potholed, dusty gray planet, and there is nothing full of life on it. Why is this the case with our moon?
There's more speculation about it, and from the origin of the moon to whether there's life on the moon, there's just too much we want to explore. When humans can come beyond the Earth, people also think about whether they can go to the moon to see what this satellite that has accompanied us for billions of years looks like. As a result, there have been a series of lunar exploration activities, and China is no exception.
< h1 class= "pgc-h-arrow-right" > the exploration of the moon</h1>
The Moon is Earth's only satellite, and there has been a lot of speculation about the birth of the planet. Some believe that the Moon was with The Earth when the Solar System was born, while others believe that the Moon was formed by debris that flew out of the primordial Earth after an asteroid impact and was originally part of the Earth.
But in any case, the moon is our closest partner, without the moon's influence on nature, whether the earth's environment is what it is now, and even whether it will produce life is unknown. Because the Moon is firmly imprisoned by the Earth's gravity, a "tidal lock" is created, with only one side facing the Earth forever, and we have known nothing about the far side of the Moon for tens of thousands of years.
After the middle of the last century, humans began their own space exploration journey, one of the important projects is the exploration of the moon. At that time, the Soviet Union and the United States were the two superpowers in the world, and they were also competing in various aspects. In order to suppress the Soviet Union, the United States began to launch the "Apollo Program" in the 1960s, and successfully sent astronauts to the moon.
The Soviet Union never achieved this goal, but launched a series of probes into the moon. In this process, the two countries retrieved a large number of lunar soil specimens, which provided an important basis for human research on the structure and evolution of the moon.
<h1 class="pgc-h-arrow-right" > Lunar Exploration Project in China</h1>
Compared with big countries such as the United States and the Soviet Union, China's space industry started late and had a poor foundation, so it takes more time and effort than others to catch up, which is the lesson that the past poverty and weakness have brought to us. Fortunately Chinese never overwhelmed by difficult circumstances, and our struggles eventually bear luscious fruit.
Today, China is already one of the most developed countries in the world's space industry, and has made great achievements in manned spaceflight and foreign exploration. Since we vowed to become a space power, we must go to other planets, so we also launched our own lunar exploration project.
After laying the foundation from Chang'e-1 to Chang'e-4, Chang'e-5 was successfully launched on November 24, 2020, and returned to Earth on December 17 with the collected lunar samples. China's "Chang'e-3" and "Chang'e-4" satellites have successfully landed on the moon, of which "Chang'e-4" is the first human creation to achieve a soft landing on the far side of the moon, which is a major feat of mankind.
The latest Chang'e-5 is also a huge step forward, and we became the third country to complete lunar surface sampling independently after the United States and the Soviet Union. After getting the lunar soil samples, China's scientists immediately put into intensive research, with the goal of discovering more secrets about the moon from the lunar soil samples brought back by Chang'e 5.
What was found < h1 class="pgc-h-arrow-right" > lunar samples brought back from Chang'e-5? </h1>
I believe that most people are most curious about the lunar soil is whether there is life on the moon, and can you grow vegetables on the moon? Researchers have long given an answer to this question: no organic material has been found in the lunar soil, which means that there is no life on the moon, and there is no way to grow plants.
While the news itself is disappointing, what the researchers have to do is far from over. For more than a year since the samples were retrieved, scientists have been analyzing them, trying to find some key evidence of the moon's history and evolution.
Although the Chinese Academy of Sciences only got 5 grams of lunar soil samples, we still made important discoveries in the study of these 5 grams of samples. Previously, the Chinese Academy of Sciences released the results of the study of lunar samples, and scientists have carefully studied the lunar sea basalts in them and found that these basalts can refresh our traditional understanding of the evolution of the moon.
First of all, we need to know that basalt is a rock formed after a volcanic eruption, but the current moon is completely "dead", without any magmatic activity. So when exactly did this happen? Where exactly is the exact time point at which the Moon ceased to operate?
Therefore, this time, Chang'e 5 chose to land in the "Moon Sea" and collect samples. The "Lunar Sea" is a very "dim" area on the Moon, not because there is water in it like the sea, but because it is mainly an area of basalt formed by magmatic activity.
After getting the samples here, Chinese scientists have used uranium-lead dating technology to determine what time period these basalts come from by extracting the uranium-rich minerals in them. As a result, these basalts came from around 2 billion years ago. The original theory was that the moon's magmatic activity ended about 2.8 billion years ago, and this result was refreshed, because the moon still had magmatic activity in the next 800 million years.
<h1 class="pgc-h-arrow-right" > surprising discovery</h1>
After determining the year in which these basalts were formed, another question began before scientists: What is the cause of the magmatic activity of these basalts, that is, the late moon?
Some people believe that the late magmatic activity of the moon is that the lunar mantle part has a large amount of radioactive elements, which release heat; others believe that the late magmatic activity of the moon is because the mantle part of the moon is rich in water, which can reduce the melting point of the magma. This time we found a large amount of "cripp material", that is, "incompatible elements", in the lunar basalt sample, which is mainly composed of potassium, rare earths, phosphorus and other minerals, which scientists believe is a sign of magmatic movement.
So, does this mean that the late magmatic movement of the Moon is caused by the release of energy by radioactive elements? Chinese scientists deny this. In their study of lunar samples, they found that these "cripp materials" did not exist at the time of magmatic activity, nor were they the material that originally formed the basalt here, but were enriched by remnant minerals on the surface in the long years after the formation of basalt.
This provides ample evidence that magmatic activity in the late Moon is not caused by radioactive elements. So, does the magmatic activity that represents the late moon must have been caused by the lowering of the melting point in the abundant water of the lunar mantle?
< h1 class="pgc-h-arrow-right" > there is water on the Moon? </h1>
If this is really the case, does the part of the mantle contain a lot of water? Will we be able to use this water in the future? However, Chinese scientists have given a disappointing answer, that is, the current moon is quite dry.
Through the study of lunar samples, we found that the number of water molecules contained in them is extremely rare, only about 1 to 5 micrograms per gram of lunar soil, which can be said to be almost water-free, that is to say, the entire source area of the lunar mantle is very dry. This discovery could prove that the late lunar magmatic activity was not caused by the abundance of water in the mantle, which means that both conventional conjectures have been overturned.
Although this result is not in line with people's "expectations", it is not a good thing for the academic community. Without our sampling and study of lunar soil, it is possible that the academic community will continue to study in two wrong directions.
China's research has undoubtedly provided a new direction for the study of lunar evolution, allowing us to get updated knowledge and continue to study the planet in the future. This is only the result of preliminary research, I believe that in the future, we can continue to get more mysteries about the moon, and perhaps we can completely uncover the secrets of the formation and development of the moon.
< h1 class="pgc-h-arrow-right" > concluding remarks</h1>
Although the moon is not rich in organic material and there is almost no water, this time does not mean that the moon is "meaningless" to us. The moon is rich in minerals, and whether it is gravity, climate or distance is very suitable, we are likely to be able to go to the moon in the future to mine, to solve the shortage of resources on our earth, which is a good thing for the entire human race.
In addition, the moon can also serve as our first stop to more distant deep space, and building a space base common to all mankind here is something we are likely to do in the future.
Before developing the moon, it is clear that full preparation is needed, such as to generate more understanding of the satellite. Therefore, we still need to continue to study the moon in the next time. Of course, Chinese will not be satisfied with just using probe sampling, we will also complete the goal of manned lunar landing in the future, so that our understanding of the moon is deeper.
It is believed that in the near future, China can become the second country to let astronauts land on the moon, complete the dream of "landing on the moon" for Chinese million years, and the ancient poem "want to go to the blue sky and catch the bright moon" will be realized in this generation.