Why Does Chang'E Bring Six Kinds Of Creatures To The Moon And Why Cotton Germinate First?

For the first time, human beings grew successfully on the biological growth of the moon, and the cotton seed became the first plant buds that man planted on the moon.

According to the "Chang'e four" biological science experiment load project team released the news, with Chang'e four landing on the back of the moon biological science test load, cotton seeds germinated successfully.

What are the difficulties in biological growth test on the moon?

How did the mysterious traveller who had completed the mission to the moon be selected?

Why do six species of cotton germinate first?

Scientists answered the topic of public concern.

Focus on 1

Which "mysterious travellers"

Go to the moon with Chang'e four?

The biological experiment of Chang'e four, headed by Chongqing University, contains six kinds of organisms, including cotton, rape, potato, Arabidopsis, yeast and Drosophila, which are placed in a sealed biological science test load tank.

Why did Chang'e four bring the six passengers?

According to the deputy director of the joint research center for deep space exploration of the Ministry of education, the chief designer of biological science experiment load, and Professor Xie renewal, Dean of the Institute of advanced technology, Chongqing University, because the biological space in the popular science payload is less than 1 liters, the capacity and resources are very limited, so screening of biological species is very important.

In addition to achieving the popular science goal of seed germination or larval growth on the surface of the moon, it is also helpful for further research on space biology in the future.

"The 6 creatures that we carry are seemingly simple, but they are the result of our hundreds of trials."

Thank you for updating.

The first condition for screening biological species is "small size".

Secondly, because of the extreme conditions such as low gravity, strong radiation and high temperature difference on the surface of the moon, it is necessary for animals and plants to withstand high temperature and freeze resistance, and also to resist radiation and interference.

So, from the mountains of Yunnan to the deserts of Xinjiang, the team searched everywhere for biological species that could survive under extreme conditions. Hundreds of plants were selected for experiments and screening.

In the process of selection, we also considered species such as tortoise, honeybee, earthworm, and so on.

Finally, we chose potato, cotton, rape and other seeds from the most basic needs of human beings such as grain, cotton and oil.

Among them, potato is a familiar food, probably a staple food in the future. Rape, as an important oil crop, is an indispensable oil guarantee for space food.

Arabidopsis, Drosophila, and yeasts are the model species of global scientists studying organisms. They are selected for the complete process of life in a short time due to their short growth cycle.

These 6 "mysterious travelers" play the roles of producers, decomposer and consumers respectively, thus forming a simple micro ecosystem.

Focus on 2

Why does cotton germinate first?

"It adapts itself to high temperature germination."

The load tank began to enter the biological lunar growth and development mode at 23:18 on the first day of January 3rd after landing on the moon.

At 20 o'clock in January 12th, the last experimental picture was sent back to the biological science experiment load tank on the back of Chang'e four, which showed that the cotton seeds sprout growing well in the pot.

In January 12th, 20 hours, 03 minutes and 34 seconds, the ground sent the biological science test load power off instruction, and the load was turned off normally.

During the biological science test load, the 6 organisms will carry out the mission of the popular science experiment and freeze at the temperature of -52 degrees Celsius at night.

It was reported that no other biological growth was observed from the data returned until the end of the experiment.

Why does cotton germinate first?

Qiu Dan, an associate professor at the school of life sciences, Chongqing University, said: "cotton itself adapts to high temperature germination, and cotton is planted in summer, and is not afraid of high temperature.

The first germination of cotton is also expected.

Xie said that the germination of seeds on the moon is undoubtedly a landmark event in the biological growth test on the moon.

When choosing plant seeds, we will consider their germination temperature. For example, cotton is suitable for germination at high temperature (more than 30 degrees Celsius); rape and potatoes germinate at low temperatures around 20 degrees Celsius.

Because we do not know the specific temperature changes on the surface of the moon, so we should consider the diversity of organisms, and we should try the species that germinate at low temperature and high temperature.

Through monitoring, it was found that after five or six days of 30 degrees centigrade, the germination of the cotton seeds was suitable for high temperature germination.

It successfully completed the task of Germinating on the moon.

In order to further verify the research results, the research team carried out a controlled experiment in the 1 to 1 closed environment and open environment.

Under the same conditions, the closed environment test is synchronized with the popular science load, and the whole process is consistent with the data environment of the popular science payload.

As of January 12th, cotton seeds germinated and grew well in the ground controlled trial pot, and green leaves were observed.

The open field experiments showed that the seeds of rape, cotton and potato had sprouted, and the seedlings showed a luxuriant growth trend.

The significance of this project is to stimulate the spirit of exploration and innovation. Two, the collected data of temperature, pressure and so on, as well as the project mode, can provide research foundation and experience for the future establishment of lunar bases.

Focus on 3

How do seeds wake up on the moon?

Five problems in cotton germination and breakthrough

Gravity on the moon is only 1/6 of the earth's temperature, and there is a temperature difference of 300 degrees Celsius between day and night.

The seeds from the earth will stay in the launch site for two months. The space flight takes a month. How can the seeds be preserved on the road and how to wake up on the moon?

This experiment has broken through five major problems: biological dormancy, "bumpy journey", water release control, sealing control, and moon lighting.

Xie said that for the long-term -57 low temperature weak air leakage phenomenon, through structural analysis, sealing material performance optimization and other methods to solve; in order to enable the popular science load to maintain stable and suitable biological survival temperature in the temperature range from -60 to -80 degrees, through the design and optimization of more than 20 thermal schemes, we finally determined the way of combining semiconductor cooler, electric heater, heat sink and insulation measures to realize the intelligent temperature control of popular science load.

In order to understand the photosynthesis of the moon, the organisms in the tank were irradiated by the way of introducing sunlight into the tank.

Through many tests, the orientation and angle of the catheter have been specially designed to avoid the plugging of the light tube by lunar dust.

For the control of the water release time, the project design chamber carried a water bag and electromagnetic pump containing 18 ml of biological special water, and sealed the new type of solvent on the water outlet to ensure that the water was released to the surface of the bio chamber on the moon to provide water for biological growth.

Xie said that this experiment has received a lot of valuable first-hand data. The project team provides research basis and experience for the future establishment of lunar bases by studying the growth and development of plants and animals under low gravity, strong radiation and natural light conditions.

Next, the project team will continue to research and explore.