Exciting, our 3 space heroes are about to return home!
The three astronauts of Shenzhou XIII have been working and living on the mainland space station for nearly 6 months, and according to the original plan, they are about to return home and are currently preparing to return home.
Like Shenzhou 12, the 3 astronauts of Shenzhou 13 will also land at the Dongfeng landing field, and all the search and rescue team members of the Dongfeng landing field have made full search and rescue preparations to welcome the 3 astronauts home safely.
I don't know if you have noticed that after the astronauts return to Earth on a mission, many people cannot get out of the return capsule on their own, but need to be carried out by the search and rescue team.
And after being carried out, the astronauts could not stand for interviews, but in a "half-lying" position. So what is the reason for this?
Why can't astronauts get up after returning to Earth?
In 2018, NASA astronaut Andrew Fauistel returned to Earth after spending 197 days on the International Space Station, and after returning to Earth, he could not walk and needed to re-learn to walk with the help of his team. The staff was very nervous as he learned to walk, fearing he would accidentally fall.
In fact, the reason why Andrew Fauistel "can't walk" is actually the same reason why continental astronauts need to be carried out.
Both the International Space Station and the Continental Space Station operate in orbit 400 kilometers from Earth, where the environment is in microgravity. It should be known that human muscles and bones are designed to adapt to the global environment, in the microgravity environment, muscles will atrophy, bone mass will be lost, and long-term will also affect cardiovascular diseases.
Astronauts are already aware of this problem, so they have specially designed a space gym for astronauts, astronauts will exercise regularly, delay muscle atrophy and bone loss, and alleviate cardiovascular problems.
However, the space environment is different from the earth environment after all, especially the three astronauts of Shenzhou XIII lived in the microgravity environment for about 6 months, and they need to re-adapt to the gravitational environment when they return to the earth.
In daily life, we feel very relaxed with a piece of paper, but for astronauts who have just returned to Earth, it is very difficult to even lift a piece of paper.
Japanese astronaut Naoko Yamazaki went to the International Space Station for a 15-day mission in 2010, and the impact on the human body in such a short period of time was actually limited, but even so, she said after returning: "I feel like my head is as heavy as a stone, and even holding a piece of paper in my hand feels difficult."
The difficulty of adapting to the earth's gravity makes it impossible for them to stand at all, and if they come out on their own, they are likely to fall in the wobble and suffer secondary injuries.
It should be known that after the astronauts have performed the mission for about 6 months, the bone density will decrease, and once they fall, it is likely to cause serious damage to the bones.
In order to protect the astronauts, coupled with the astronauts' bodies are difficult to stand, the search and rescue team must carry the astronauts out after finding the astronauts, and cannot let the astronauts out.
Not only that, but the astronauts who are lifted out should avoid standing, but should sit on a special chair, which has a backrest, which can allow the astronauts to sit on it in a half-lying posture and make the astronauts appear in the best posture as possible.
Of course, if it is a short-term task, the impact on the human body is relatively limited, and at this time, you can walk out of the return capsule by yourself.
Why do astronauts quarantine?
After the astronauts leave the capsule, in addition to appearing for the media to take pictures, they will also simply accept interviews with one or two media. They are then taken by plane or other means of transport (carried across the route) to quarantine points.
The purpose of the quarantine is not because there is a virus on the space station, but because after the astronauts have carried out the 6-month mission, the body's immunity will decline, and some common viruses on Earth may cause them to get sick.
During the isolation period, astronauts will refer to the three-level isolation system, not only the astronaut's residence should be disinfected and ventilated every day, but all the staff should be isolated in the apartment, can not move around at will, all people who enter the apartment must wear protective clothing, physical examination and disinfection before entering, after entering can not hug the astronaut, as well as shake hands.
With the recovery of astronauts' physical fitness, the isolation system for astronauts will also be slowly adjusted downwards, of which the second week to the third week after return refers to the level II infectious disease prevention and isolation system, and then adjusts to the level I infectious disease prevention and isolation system.
After isolation, astronauts also need to undergo medical recovery, convalescence, etc., and when the physical fitness returns to the pre-flight state, astronauts can continue to participate in training and prepare for the next mission.
Why are astronauts older?
At present, when the mainland astronauts are carrying out their tasks, they adopt the "old with the new", which is simply that the first batch of astronauts bring the second batch of astronauts, and the first batch of astronauts are older, many of whom are more than 55 years old, such as: Shenzhou XII astronauts Nie Haisheng and Liu Boming. Tang Hongbo, another Shenzhou 12 astronaut, was 47 years old.
The three Shenzhou 13 astronauts are: Zhai Zhigang is 56 years old, Wang Yaping is 42 years old, and Ye Guangfu is 42 years old.
So why are mainland astronauts older, and there are no young people in their 20s and 30s?
On the one hand, this is because in the past, in the basic conditions for candidates for astronauts on the mainland, it was stipulated that candidates must be test pilots with aviation flight experience and excellent active pilots of the Air Force, and there were requirements for flight time. Being able to meet this criterion means that age cannot be too young.
On the other hand, at present, only the first and second batches of 16 active astronauts have flight experience, although the third batch of astronauts have been selected, but they are still in training and cannot perform missions, while the continental space station is a long-term mission, requiring at least two batches of astronauts per year, a total of 6 astronauts to the space station to carry out missions.
Among them, the older group of astronauts is more experienced, and adopting the old belt and new model can allow the new generation of astronauts to reduce exploration and more directly impart experience.
The third batch of astronauts has now been selected, and the selection conditions are still very demanding as in the past, but compared with the past, two positions of space flight engineer and payload expert have been added.
Therefore, the third batch of astronauts was not only selected from the pilots of the Air Force, but also selected scientists, engineers, etc. from scientific research institutes and scientific research units.
Among them, astronaut engineers need a master's degree or above, and payload experts need a full-time doctoral degree. Need to have 3 to 5 years of work experience, under various conditions, the age of the selected reserve astronauts will not be too low, so 40 or 50 years old is actually the golden age of astronauts.
At present, the third batch of astronauts is training, it is expected to take 2-3 years, during which the first and second batch of astronauts are still the main force, and when the third batch of astronauts returns from school, it will greatly alleviate the pressure on the continental astronauts.