It is worth mentioning that this time, Shenzhou XIII adopted the fast return scheme for the first time, and the spacecraft only needs to turn in the sky for a few hours to enter the return orbit, which not only shortens the waiting time of astronauts, but also increases their comfort.
During the six-month space mission, the three astronauts not only did many interesting experiments, but also obviously changed their bodies.
Now that the day of "going home" is approaching, what preparations should they make in advance? What challenges will it face?
1. The astronaut's face became "puffy"
For this problem, some people think that it must be too comfortable in space to "gain weight". In fact, astronauts are under great pressure in space.
They not only do experiments, but also record data every day. In the weightless environment, they need support to stand and eat, which is difficult for ordinary people to adapt.
Moreover, they usually do some fitness exercises after meals, so their weight will not change much. This "edema" phenomenon is a normal physiological reaction. This is because in the weightless environment, body fluids will be more distributed in the head, and this situation will disappear after returning to the earth.
2. Astronauts will be taller.
Astronauts will grow taller in space. When people are on the earth, the spine is in a state of compression due to gravity. In space, if there is no constraint of gravity, their spines will stretch as much as possible, and their height may increase by about 2-3cm, up to about 5cm.
However, this increase occurred under certain conditions in space, and it will slowly return to its original state after returning to the earth, so this height is not a real height.
It is the same reason that you wake up taller in the morning than before going to bed at night. Because the standing and sedentary vertebrae are compressed during the day, they relax at night and return to their original shape. It is not a good thing for astronauts to grow taller. They may be accompanied by symptoms such as cervical pain.
In addition, in the long-term lighting environment, their heart function will gradually decline, and they are prone to osteoporosis, and their immunity will also decline due to radiation, which needs to be slowly recovered after returning to Earth.
1. Strengthen physical exercise, and enhance bone and heart and lung functions.
Astronauts have been in the sky for nearly six months. It is mentioned above that their bodies will undergo some major changes in space. In order to better adapt to the gravity environment of the earth, they must improve their living habits.
In fact, astronauts live a regular life in the space station and usually exercise regularly. However, after returning to Earth this time, their bodies will definitely not be able to adapt immediately. They must strengthen their exercise and enhance their muscles, bones and cardiopulmonary functions.
In addition, they also have cardiovascular and cerebrovascular conditioning, which helps to reduce the harm to the body and restore the state faster to ensure safe return to China.
2. Recover the experimental data generated in orbit.
Astronauts come not for fun, but with arduous tasks. In addition to completing the mission, they will also bring back the experimental records and materials in orbit for research. These experiments are of great value, which will help human beings to better understand life and break through the bottleneck of science.
For example, the "calcium signal flicker" of heart cells in weightlessness was observed for the first time, and the cabin transposition assisted by mechanical arm was carried out, which also made more teenagers understand that space in weightlessness is different from real experiments.
After the mission of Shenzhou XIII is completed, Shenzhou XIV will be launched, and the space station assembly and sky science experiments will be carried out again on the basis of Shenzhou XIII.
After the launch of Shenzhou XIV, Shenzhou XV will also be launched. This is not only the first time in human history that six astronauts went into space together, but also a perfect demonstration of China's ability in the space field.
3. Pack your luggage and put the extravehicular service back in its original place.
When the three astronauts first went to heaven, many netizens were concerned that they had lived in the sky for six months. What did they eat? What to drink? How to live?
In fact, we don't have to worry about these. The Tianzhou-3 cargo spacecraft has transported more than 200 packages and about 6 tons of materials, including dehydrated food, drinking water, oxygen, experimental equipment, women's cosmetics and emergency supplies.
Previously, Shenzhou-12 did not use up all materials during its mission, and some materials remained in the space station.
Besides, Shenzhou XIII itself can also bring some portable materials, such as kung pao chicken, fish-flavored shredded pork and other convenience foods. All these materials add up to enough for three astronauts to use for six months.
Now that they are at home, they should put all the materials in order and put back the experimental equipment and extravehicular services, which can provide convenience for people who come to the space station in the future.
Clean up space junk
In addition, the three astronauts have to deal with domestic garbage for six months, knowing that the materials they use every day are packaged and non-degradable.
Every time they finish eating, they will produce some kitchen waste, but these wastes are not directly mixed together, but different wastes need different classification. The paper towel plastic bag is reduced in size by vacuum compression, and the wet garbage will be put into a special bag for recycling.
We should know that in the weightless environment of space, food residue will float in the air if it is not cleaned up, and once the astronauts are choked, it will endanger their health.
Because the life of three astronauts on the space station needs to drink a lot of water, although the supply of the space station is sufficient, their urine will be recycled.
After special purification, these urine will eventually become drinking water, and the residual urine alkali will be packed and transported away. Space junk will be taken to the earth's atmosphere and burned, in order to give space a pure land.
5. Adjust your mood and check the spacecraft system.
The three space heroes are going home soon, but they are both happy and uneasy. They are happy that they have successfully completed their mission, but they are also worried that they may encounter danger in the process of returning to earth.
Therefore, in order to avoid mood swings, their first task is to adjust their emotions. Only when you are in a good mood will you not panic when you encounter something.
Secondly, they should check whether there is any fault in the spacecraft system, be familiar with the return process and communicate with the control center on the ground. Report problems in time to avoid mistakes. Finally, when everything is ready, they can go home.
However, space is full of unknowns, which will not only be "dangerous" when returning, but also affect the health of the three astronauts after returning to Earth. So what challenges will they face?
Returning to Earth from space is a severe test for three astronauts. Previously, the flight speed of Shenzhou XIII spacecraft was 7.9 km/s, and this time it will adopt a quick return plan, which means the speed will be faster, so the three astronauts should be psychologically prepared in advance.
On the one hand, a "black barrier" will be formed in the process of rapidly falling into the atmosphere. After entering the black barrier, the communication will be interrupted for 4-7 minutes, and the return capsule can't contact the ground command, which is very scary.
On the other hand, rapid falling will have a strong impact on people's health. If ordinary people are definitely dizzy, it is tolerable for astronauts, but their body and mind will also be affected. This exam is a challenge for them.
Astronauts are not only in danger when they take off, but also when they return. Previously, we saw on TV that astronauts were put in wheelchairs when they landed for the first time. Many netizens expressed incomprehension, and it was really distressing to see the reason.
Three astronauts lived in weightless space for six months. When they return to the earth, their brains will be short of blood supply due to gravity, so they can't walk upright.
Moreover, the three astronauts have been in space for too long, the bones become loose and easy to fracture, the muscles will also shrink to a great extent, and the heart rhythm will be problematic. It will be dangerous to stand suddenly, and they must sit in a wheelchair to re-adapt to the gravity environment of the earth.
Fortunately, the Dongfeng landing site was chosen for this landing site, and the ground staff will conduct all-round docking with the astronauts to ensure that the astronauts can reach the ground safely.
After the three astronauts arrive on the ground, they will first carry out "medical isolation", which is to prevent space bacteria from mutating and affecting the astronauts' bodies.
On the other hand, it is to help astronauts better adapt to the earth's environment, because just coming back from space, muscles will shrink to varying degrees, and calcium in bones will also be lost, which can be recovered through diet therapy during isolation.
After that, the three astronauts will be sent to a nursing home for rehabilitation. Mainly due to the decline of physical function and low immunity. So there are special people to take care of their diet and daily life, but their bodies will recover faster.
Although the astronauts' physique is different from that of ordinary people, they have stayed in space for too long, and it takes a long time to adapt to gravity, and may be accompanied by depression.
So the best way is to practice quietly and return to the previous state through diet exercise and psychological counseling. In short, they have completed the arduous task, and it is also appropriate for them to recuperate and adjust themselves.
Zhai Zhigang, Wang Yaping and Ye Guangfu, three space heroes, are the pride of 65.438+0.4 billion China people. They have paid too much bitterness to explore the mysteries of the universe, and their bodies and minds have been hurt to varying degrees.
Now they "go home", wish them success in their mission, look forward to their early and safe return, pay tribute to the space heroes, and look forward to the motherland's space technology standing at the top of the world.