If you want to live on the moon, you must understand these issues

Chairman Mao wrote in the poem "Shui Tiao Ge Tou: Re-ascending Jinggang Mountain": "I can reach the moon in the sky, I can catch turtles in the five oceans, and I can return home with a triumphant song. Nothing is difficult in the world as long as you are willing to climb." More than 50 years later, Chairman Mao's dream of reaching the moon in the sky is gradually being realized by us. During the Mid-Autumn Festival holiday, let's talk about the story of lunar soil and how to build a house on the moon.

Image source: Internet

1. The past and present of my country and lunar soil

1. From 1 gram to 1731 grams, my country's lunar exploration project has gone through 81 difficulties

In 1978, the United States gave China a 1-gram lunar rock sample, and the country decided to split it in two - half for public display and half for scientific research. According to Ouyang Ziyuan, the first chief scientist of China's lunar exploration project, the sample was a small stone in plexiglass, "only the size of a soybean." After more than four months of research on this half gram of lunar soil, Ouyang Ziyuan said: "The Americans said that they only gave you such a small amount, and you know everything." But his biggest dream in his heart is to have a "lunar sample collected by China itself."

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In the early morning of December 17, 2020, in Siziwang Banner, Inner Mongolia, after overcoming many technical difficulties such as lunar landing, automatic sampling, lunar takeoff, lunar orbit rendezvous and docking, and re-entry, the Chang'e 5 returner, which had gone through "ninety-nine and eighty-one difficulties", finally successfully returned to the ground carrying 1,731 grams of lunar soil.

2. The moon can meet the Earth’s energy needs for 10,000 years!

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Why are major countries in the world, including the United States and China, actively exploring the moon? This is because of its huge development value. After various explorations and analyses, it is found that there are rich mineral resources on the moon. The lunar sea basalt alone contains at least 100 trillion tons of exploitable titanium metal. Since the moon has no atmosphere, there is a large amount of helium-3 blown by the solar wind in the lunar soil on the surface of the moon. This is a safe, clean and efficient nuclear fusion power generation fuel. Using it for nuclear fusion power generation can provide cheap, non-toxic and non-radioactive energy, and is called "perfect energy" by the scientific community. According to conservative estimates, there are 1 million tons of helium-3 in the lunar soil, which can be used to generate electricity to meet the energy needs of the earth for 10,000 years.

2. If you want to live on the moon, you must understand these issues →

The moon is the closest neighbor to the earth, and generations of human beings have been curious about living on the moon. Can vegetables be grown on the lunar soil? Is there water in the lunar soil? Through the discoveries of the lunar exploration project, especially the study of the lunar soil brought back by Chang'e 5, we can preliminarily answer some questions:

1. Can vegetables be grown on lunar soil?

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Pure lunar soil does not contain any organic nutrients and is very dry, so it is not suitable for growing vegetables. If people go to live on the moon in the future and modify its planting environment accordingly, it may be possible to grow vegetables on the moon.

2. Is there water in the lunar soil?

There is very little water in the lunar soil, but it does exist. New findings show that one ton of lunar soil contains an average of six mineral water bottles of water molecules that can be extracted. The lunar soil collected by the Chang'e-5 lander will provide a direct basis for assessing the content of water molecules in the lunar soil in its landing area.

3. What does the discovery of water molecules in lunar soil mean to us?

Water is the source of life. Previous exploration results show that there is no liquid water on the moon as we imagine. It exists in the form of gaseous water and solid water. Where do these water molecules come from? Are they sent to the moon with countless meteorites? Or is there another reason? Can we effectively extract and utilize them in the future? These questions are related to our future journey to the starry sky and the "vanguard" to solve the problem of human habitation on the moon and even more planets.

4. What is the special value of the lunar soil retrieved by Chang’e 5?

In fact, the lunar soil retrieved by Chang'e 5 is more than 1 billion years old! Studying them will help us study the moon, the earth, and even the origin of the universe.

5. Can we build a house using lunar soil?

Image source: Internet

The answer is yes. There are two main ways to build a house on the moon.

The first is to bring parts from Earth for assembly. We can first manufacture multiple rigid cabins with different functions on the ground, then send them to the lunar surface via a launch vehicle, softly land on the lunar surface, and then connect them together like building blocks to form a complete living area. This method is somewhat similar to assembling the International Space Station. For example, we build a living room, kitchen, bathroom, and bedroom separately, send them to the moon separately, and then assemble them into a complete house. According to the current concept, the lunar base assembled in this way can provide 3 to 6 astronauts to stay and meet the astronauts' living and working needs. If the launch vehicle can be reused in the future, the cost of transportation will not be unacceptable.

The second method is to use local materials. Unlike the first method of bringing your own dry food, we can mine lunar ore and dust as raw materials, and then through certain processing such as 3D printing, turn lunar rocks and lunar soil into usable building materials for construction. This method can build a large-scale base group to form a large lunar base, which can provide a living and working environment for more astronauts and scientific researchers.

Even scientists imagine using the long, winding channels under the lunar surface - lava tubes, to build a safe underground city that can withstand the impact of asteroids and easily control the internal temperature. Although scientists' ideas are only based on predictions, cities on the moon may become a reality in the future.

3. Have you heard of these rumors about lunar soil?

Through the study of lunar soil, some online rumors can also be clarified:

1. Does lunar soil smell like a volcano?

According to records, foreign astronauts said that the lunar soil had a burning smell, like wet fireplace ashes, or like the air after a fireworks display. But after returning to Earth, scientists did not smell any odor in the samples.

2. Is the lunar soil black?

The real lunar soil is not the black color we observe on Earth. When you magnify it, it is actually colorful, and there are also colored glass-like substances.

From 1 gram to 1731 grams, it is the result of the hard work of generations of astronauts. The exploration and research of lunar soil is an important step for us to unveil the mysterious universe. In the future, China will move towards the moon, Mars and even deeper space, and Chinese astronauts will provide a Chinese solution for the peaceful use of space by mankind.

Author: Qian Hang, Senior Model Designer, General Design Department, China Academy of Launch Vehicle Technology

This article was published by Tencent's "Everyone Loves Science" team

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