How do astronauts sleep in space?

Describe ordinary things only when they are extraordinary. Sleep is extremely ordinary, but Zhang Fei's sleeping with his eyes open, sleeping on a shoulder pole, sleeping while marching, etc. are very extraordinary. Describing them makes people talk about them. Space sleep is also extraordinary and needs to be described here.

The reason why sleeping in space is extraordinary is that the environmental conditions there are very different from those on the ground. When the spacecraft flies around the earth, it is in a state of weightlessness. This is the main reason why sleep in space is different from that on the ground. In addition, there are different day and night rhythms, noise interference, etc.

When beds are tight, I often hear this joke: I’ll hang you on the wall tonight. There's nothing funny about this way of sleeping during spaceflight. In a weightless environment, you can sleep no matter where you are (floating in the air, leaning against the wall, tied to the bed). However, many people are not used to floating sleep. An American Apollo spacecraft astronaut said: "When you find that your body has nothing to support underneath during sleep, you will have the feeling of falling into an abyss." At the same time, for safety reasons, it is best to sleep In the sleeping bag, fix the sleeping bag to the bed or wall to prevent it from floating around and causing collision accidents when the spacecraft has speed changes and vibration shocks. Taking into account people's sleeping habits on the ground, the United States set up multi-level horizontal beds on the space shuttle. Each bed is 1.8 meters long and 0.75 meters wide. There is a fire-proof sleeping bag. The sleeping bag is connected to the bed through ropes and hooks. When sleeping, get into the sleeping bag, zip it up, tie the waist with a belt, and you can sleep. However, many people are not used to sleeping on multiple bunks. A European astronaut said that when he slept in the lower bunk, he felt as if he was sleeping under the bed. Some people prefer to sleep in the space between the two decks. In fact, if you hang the sleeping bag on the wall, you can still sleep well. If you place the sleeping bag close to the wall, your back can be straightened during sleep, and it will feel like sleeping on a bed, except that a vertical bed takes up 23% more space than a horizontal bed. The European Space Agency has designed a new sleeping bag, a double-layer inflatable sleeping bag. After inflating, the sleeping bag is tightened, exerting a certain amount of pressure on the human body, which not only improves blood circulation in the chest, but also eliminates the drifting feeling of free falling.

In a weightless environment, you can sleep in any position (lying flat, upright, hanging upside down, curled up). However, if you completely relax and sleep, your body will naturally bend slightly into an arch shape. Most astronauts find it more comfortable to sleep slightly bent than fully extended. However, in order to prevent back problems, it is best to sleep with your back straight.

In a weightless environment, all weight disappears, the head and body feel separated, and the arms seem to be floating freely. A former Soviet cosmonaut once slept with his arms on his sleeping bag. When he woke up, he found two hands floating towards him in the hazy state, which made him break into a cold sweat. Therefore, it is best to put your arms into the sleeping bag when sleeping. When sleeping in a small spacecraft cockpit in the early days, in order to prevent accidentally touching the switch, it was necessary to bind the hands in front of the chest while sleeping.

In a self-sufficient agricultural society, the general law of life is "work at sunrise and rest at sunset." In modern society with developed industry, "night wandering gods" who sleep during the day and are active at night have appeared again. A manned spacecraft flying in low Earth orbit. It usually takes about 90 minutes to fly around the earth, that is to say, a day and night cycle is only 90 minutes, with 45 minutes each day and night, and there are 16 alternating days and nights in 34 hours. This change in circadian rhythm makes it impossible for astronauts to "work at sunrise and rest at sunset", nor can they work at night and sleep during the day. In order to maintain the life rhythm formed on the earth, the 34-hour cycle is still used during spaceflight. Arrange the astronaut's work and rest time, generally 8 hours of work, 2 hours of dining, 1.5 to 2.5 hours of exercise, 3.5 to 4.5 hours of activity, and 8 hours of sleep. In order not to let the rapid circadian rhythm affect your sleep, you should wear an eye mask while sleeping. A more advanced method is to use changes in light brightness to simulate the circadian rhythm on the ground to ensure that astronauts can sleep well.

However, the noise generated by various instruments and equipment during operation will still affect the pilot's sleep. Therefore, you should also wear a soundproof hat when sleeping in space. A further step is to isolate the bedroom from the rest of the house and use sound-absorbing materials to reduce the intensity of the noise.

In order to enable the astronauts to sleep well, radio contact with them on the ground was also stopped so as not to disturb them.

On a multi-person spacecraft, a rotating work system is generally adopted to ensure everyone's sleep.

Nevertheless, there are still many accidental factors that affect astronauts' sleep. For example, in March 1982, when the U.S. space shuttle Columbia was flying, Commander Lomas did not sleep well most of the time due to static interference in the cockpit. The "crackling" sound of static electricity also affected the sleep of other astronauts. It makes everyone very tired. Ground command centers had to rearrange their schedules. When some astronauts first enter space, they can't sleep well due to excitement, and some have insomnia due to being too tired from work and other reasons, so they need to rely on the help of drugs.