Tianzhou 2, which was once part of the space station, has been controlled to crash, the Shenzhou 13 astronauts on the space station are about to triumph, Shenzhou 4, Shenzhou 14 and Shenzhou 15 are ready to go, two groups of astronauts have been selected, and the Chinese space station will soon usher in the most brilliant period in China's space history.
Now, Shenzhou 13 astronauts are strengthening their exercise, "space treadmill", "space bicycle" and other sports equipment are used, and the exercise time has increased from the previous 2 hours to more than 3 hours now, and it may even be 4 hours, all in order to better adapt to the gravitational environment after returning.
After the spacecraft lands, search and rescue personnel and film crews will arrive at the landing site in the fastest time, and many people hope to see the triumphant space hero at the first time, but they generally have to wait for dozens of minutes before leaving the capsule, and it may even be 40 minutes. The question is, the capsule is supposed to be an extremely simple thing, why do astronauts have to wait nearly 40 minutes to get out of the cabin?
Let's first understand the physical changes of astronauts in space life for a long time, there are three major changes, one is the change of body blood supply, the second is loose bones, the third is the change of muscles throughout the body, and other changes will not be discussed.
The body's blood supply changes, the human body is accustomed to the ground gravity environment, the heart balances the blood supply to all parts of the body, but in outer space, due to the lack of gravity constraints, the amount of blood flowing to the head naturally becomes more, on the contrary, the amount of blood flowing to the lower part of the body naturally becomes less.
The human body has the ability to automatically regulate, in order to reduce the amount of blood flowing to the head, the human body will automatically control the amount of blood in the body, which will lead to the astronauts in space may appear symptoms of anemia.
Loose bones, the main component of human bones is calcium and other minerals, bones mainly rely on gravity to accumulate these minerals, but in space without gravity, the mineral density in the bones is reduced by 1-2% per month, if it is 6 months, then the mineral density of the bones is reduced by 6% to 12%, and the bones become brittle, especially the legs.
This is osteoporosis, is a condition that the elderly are easy to suffer from, when osteoporosis occurs, the easiest way is to supplement minerals, such as taking calcium tablets and the like, but even if astronauts in space supplement more calcium tablets, it is difficult to be absorbed by bones.
The whole body muscle changes, 206 pieces of human bones, but the human body muscles exceed 639 pieces, on the ground, in order to cope with gravity, people's 639 muscles are working hard every day, especially the thigh muscles, which have to support hundreds of pounds of body for a long time every day, including running, jumping and jumping.
But in outer space without gravity environment, the power of a finger can make you float out of tens of meters, almost all without thighs, thighs lose their role, leg muscles begin to atrophy, so do muscles in other parts, the longer you spend in space, the more serious the muscle atrophy.
Physical exercise can indeed prevent muscle atrophy, but no matter what method is used, it is impossible to make 638 muscles of the whole body participate in exercise, and the muscles that can really be exercised are only a few dozen muscles, so most muscles will atrophy.
After the spacecraft landed, why did the astronauts wait for nearly 40 minutes before leaving the capsule? This is out of consideration for the physical health of astronauts, astronauts return from space, suddenly from the zero gravity environment into the gravity environment, which requires a short adaptation process, waiting for the body to adapt to the cabin.
As mentioned earlier, astronauts in space may have symptoms of anemia, when returning, the body's blood supply has changed again, a large amount of blood has begun to flow to the legs, the head blood supply has suddenly decreased, the symptoms of anemia will be aggravated instantly, dizziness, blurred vision and other symptoms may appear, if it is impossible to alleviate after dozens of minutes, it may be necessary to increase body fluids.
Due to the atrophy of the astronaut's body muscles, suddenly from the zero gravity environment into the gravity environment, which also requires a process of adaptation, coupled with the body osteoporosis, I am afraid that even standing is a difficult task.
Do you know how far space has atrophied astronauts' muscles? Canadian astronaut David St. Jacques, who returned in June 2019, said: "When I first returned, I had a hard time even speaking, I obviously felt the weight of my lips and tongue, and I had to change the way I spoke, and it took a long time to adapt to it.
China's aerospace science popularization column wrote on Weibo: Astronauts need a period of time to re-adapt to the gravitational environment after returning to the ground. The scientific departure time should be about 40 minutes after the landing of the return module.
After returning to the ground, the astronauts can not return to normal life in a short period of time, under the guidance of experts, it takes a recovery period of 3 months to a year, the change of blood supply and muscle atrophy in the body, generally recovered within 3 months, the slowest recovery is osteoporosis problem, it may take longer, of course, this also depends on the situation.
Shenzhou 13 returned in mid-April, it is now April, we will soon see the heroic appearance of the space hero, many Chinese people are breaking their fingers to calculate the day when the Shenzhou 13 astronauts returned, especially the family members of the space hero, they must miss them very much. Interesting and informative scientific content, please pay attention to the only WeChat public account: Interesting Exploration