Why can't astronauts get out of the return capsule right away after returning to Earth? Why do they have to lie down after leaving the capsule?

Friends who have watched the live broadcast of the return of the Shenzhou spacecraft may have a question: why does it always take a long time for the astronauts to meet everyone after the return capsule lands, and why can't they come out immediately?

In space, astronauts are usually in a floating state because the gravity they are subjected to is extremely small. Without the interference of gravity, astronauts' perception of up, down, left and right is reduced, and the need to maintain body balance also disappears.

Astronaut Tang Hongbo floats and flips in the space station

Six months later, when they return to the ground, gravity regains control of the astronauts' bodies, firmly pulling them downward. However, the astronauts' balance system has become accustomed to the life of "lying flat" in space, and is suddenly forced to "roll inward", unable to accept the sudden change in the environment. As a result, the astronauts may experience symptoms such as dizziness, nausea, and vomiting.

How uncomfortable is it? Imagine the feeling of being dizzy after riding a roller coaster. I guess the return capsule should be its "pro", "plus" or "upgraded version".

Fortunately, this state is relatively short-lived. As long as we give the astronauts some time to adapt to the Earth's gravity environment, they can leave the cabin on their own if they do not feel any obvious discomfort.

Since the astronauts were not feeling unwell, why did they keep lying on the recliners after leaving the cabin?

This is all about life in space. For six months, due to the near absence of gravity, the astronauts had very little weight on their bodies. In addition, due to the limited space in the cabin, the astronauts could not move and exercise like they do on Earth. As a result, their bodies gradually experienced changes such as muscle atrophy and bone loss.

Some of you may ask, don't astronauts also exercise in space? Yes, but exercise on the space station can only slow down the degree of change, it cannot prevent the change from happening.

After returning to Earth, due to muscle atrophy, the astronauts' bodies are not strong enough to support them standing, and they will also appear pale, weak, and have low blood pressure. Bone loss makes the astronauts very fragile and prone to fractures. In addition, the astronauts are still wearing space suits weighing about 10 kilograms, so it is very dangerous for them to stand and walk on their own.

Astronauts return wearing space suits

In addition, changes in body fluid distribution also force astronauts to "lie flat." In space, astronauts' body fluids are evenly distributed throughout the body, making the face look swollen, a phenomenon also known as "moon face."

Comparison of facial changes of the Shenzhou 15 astronaut crew before and after going into space

After returning to Earth, due to the effect of gravity, body fluids will be redistributed, and a lot of body fluids will be concentrated in the lower limbs. This will reduce the swelling of the astronauts' faces, but will have a great impact on the body's circulatory system, especially the cardiovascular system.

In order to allow the body to gradually adapt to this change, astronauts need to reduce exercise as much as possible and reduce the burden on the body to avoid stimulating the circulatory system and damaging the body. Therefore, we see that astronauts lie on reclining chairs after returning.

Astronauts lying on a recliner after leaving the return capsule