Eat - The easiest thing becomes complicated and wonderful
Eating and drinking water is a very common thing for people living on Earth, but in the weightless environment of space life, the diet of astronauts has become very complex and particularly wonderful. It can be said that the nutritional needs of astronauts, food preparation, supply and their way of eating have certain particularities, and they are very different from the diet they live on the ground.
Space food is essentially the same as ordinary food on the ground, providing energy and nutrition for the human body. But in order to save space on the spacecraft and the payload at launch, the space food carried by astronauts should be as light and small as possible. Such as nutritious dried biscuits and dried sausages, when eating with a blister, you can restore the taste of fresh food. In addition to being able to withstand the impact of special environmental factors in space, such as shock, vibration, acceleration and other tests without failure, space food must also be appropriate to adjust the dietary nutrients for the physiological change index of astronauts in weightless conditions, such as muscle atrophy requires that food must provide sufficient high-quality protein; Bone loss requires food to provide adequate calcium and appropriate calcium and phosphorus ratios and vitamins.
How astronauts eat during space flight is a big test for them. In weightless conditions, a glass full of water is placed upside down, and the water in the glass does not float or spill out automatically; if placed on a table, the glass will fly up with the water. Therefore, the astronauts' original habits of eating and drinking water on the ground are completely unsuitable in space. Generally speaking, all kinds of food, parts, utensils, etc. are fixed. After the astronaut takes out the food from the pantry, he has to cut a small opening in the composite plastic bag containing the food, put a fork and chopsticks into the pocket and fork into the mouth. In order to prevent food debris from flying around and affecting the normal work of astronauts or equipment, this food is often packed in small packages, made into squares, rectangles or small balls similar to the size of the mouth, and you do not have to cut it when eating. If astronauts want to drink water, they can eat soup, soup, juice or jam directly from a plastic pocket or a soft aluminum tube shaped like toothpaste, and squeeze it into their mouths.
With the development of rocket technology, astronauts can bring more food from the ground. Such as wet food or semi-wet food with juice Turkey, beef, etc., their moisture content is the same as the normal food eaten on the ground. Astronauts can now use microwave heaters to bake food in their capsules. This microwave heater is different from the heaters used on the ground. It has some special indented little boxes in it. In order to prevent the food from floating when heated, the food that needs to be heated must be fixed in these small cells, and when plugged in, the food can be heated to a delicious degree in a short time. With it, astronauts can taste hot, fragrant braised beef, scrambled eggs, pork chops and other food, its taste is not much different from that on the ground.
Wear - A dress costs tens of millions of dollars
People's understanding of clothing is often limited to its characteristics such as covering, warmth, beauty, and generosity, but when humans enter space, they will find that the role of space suits has long exceeded the traditional category. Because the pressure environment of space close to the vacuum, the extreme temperature environment, the lack of oxygen required for life, the threat of space meteorite, space debris and space radiation, etc., all need space suits to provide a good protection and guarantee system for astronauts to live and work in space.
Space suits can be divided into cabin space suits and extravehicular space suits according to their functions. The cabin space suit is used for when the spaceship cabin leaks and the pressure suddenly decreases, the astronauts put it on in time, connect the oxygen and gas supply system in the cabin, and the clothing will immediately be pressurized and supplied with gas, and can provide certain temperature protection and communication functions to ensure that the astronauts can return safely when the spaceship fails. The extra-vehicular space suit is more complicated. It is the guarantee and support system for astronauts to go out into the open space for activities. It not only needs to have independent life support and working capabilities, including extreme thermal environment protection and human balance control, oxygen supply and pressure control, ventilation and purification of the microenvironment in the suit, measurement and control and communication systems, power supply systems, and astronaut visual protection and protection. It also requires a joint system with good mobility and an emergency oxygen supply system in case of major system failure. The structure of the extravehicular space suit is composed of micro-flow protection layer (outer cover), vacuum heat insulation shield, airtight restriction layer, ventilation structure and liquid cooling suit, like an independent life support system. An extra-vehicular spacesuit system usually weighs much more than a strong person. It is naturally expensive, and it currently costs tens of millions of dollars to develop and produce an extra-vehicular space suit.
When it comes to space suits, we cannot fail to talk about \"space jet packs\". The backpack is about 1.25 meters tall and 830 millimeters wide, weighs 150 kilograms, contains 12 kilograms of liquid nitrogen, and has 24 nozzles. It is like a chair without a seat, which is attached to the astronaut's back. Astronauts can control 24 tiny nozzles through switches on the armrests to spray compressed nitrogen from the backpack, thus forming different sizes of reverse thrust in each direction to achieve different directions of movement. With the jetpack, astronauts will be able to somersault, spin and move up, down, forward and backward at will in the vast expanse of space.
Live - Life in a capsule tests skills
The cosmic environment is extremely harsh, and the main factors harmful to the human body are high vacuum, high hypoxia, cosmic radiation, temperature differences, etc. Astronauts cannot live and work in such an environment. So, scientists have developed a kind of sealed environment cabin to protect the astronauts.
The airtight cabin for astronauts to live, live and work is a major part of the spacecraft, and it is the environmental control and life support system to ensure the health of the astronauts. The most important life support system is the water supply system. Its main mission is to provide astronauts with water for living and eating. The airtight cabin is a small environment, and the pollutants that are constantly produced must be purified to maintain the fresh air inside the cabin and ensure the health of the astronauts.
Because of weightlessness floating, astronauts do not move as freely as on the ground, sitting unstable and wobbly, a little lift up the body may come to a big roll, bending down may somersault, so all movements have to be careful. During space flight, sleeping bags are usually attached to the bulkhead inside the spacecraft. In weightlessness, it is not easy to sleep up and down, standing up and lying down, so the astronaut can either sleep against the ceiling or stand up straight against the wall, as long as he likes. To prevent inadvertently touching the switch, they must sleep with their hands clasped in front of them. The space sleeping position is very special, weightlessness, the body is completely relaxed will naturally form an arch position. On the space station, astronauts already enjoy separate bedrooms and beds, but they have to tie themselves to the beds when they sleep, so as not to float away when they turn over due to weightlessness.
In addition, astronauts in space and people on Earth, also need to have personal cleaning and hygiene treatment, such as brushing teeth, washing face, bathing, urination and so on, but all these need to have special facilities and skills. For example, when brushing teeth in weightlessness, toothpaste foam is easy to float, and water droplets fly in the cabin, which will affect people's health and the normal operation of instruments. In order to prevent this problem, the United States uses a special gummy candy, let astronauts fully chew instead of brushing, to achieve the purpose of cleaning teeth. Astronauts need to plug their ears and wear goggles when showering, just like divers do. When people enter the bathroom, they should put on fixed slippers so that they do not float. The US space shuttle Endeavour is equipped with a space toilet that costs a whopping $23.4 million. This toilet can store and process more feces, and has a separate urine separator to separate urine and feces. The air flow guide device on the toilet solves the difficulty of human excretion under the condition of weightlessness.
Fine - to prevent becoming a human satellite in the vast space
On March 18, 1965, Soviet cosmonaut Leonov left the airtight cabin of the \"Ascent\" 2 spacecraft and walked in the vast space for the first time wearing a seat belt, creating a precedent for human spacewalking. However, space walking can not be compared with walking on the ground, and its degree of difficulty is unimaginable to ordinary people, requiring many special technical safeguards.
Because space is in a vacuum, there is no atmosphere to protect, the temperature change is also very large, the temperature can be higher than 100 ° C when the sun is shining, the temperature can be lower than -200 ° C when there is no sunlight, and there are various radiation and micrometeoroids that can harm the human body, so in the space walk, you must wear a special space suit. At the same time, since the artificial air pressure and air composition in the closed cabin of manned spacecraft such as spacecraft, space station and space shuttle are basically the same as that on the ground, there is a certain amount of nitrogen in the body, and the air pressure in the space suit is low, only 27.5% of atmospheric pressure. If the astronaut suddenly leaves the cabin, the blood supply will be poor after the low air pressure. Nitrogen dissolved in fat tissue can't be carried through the blood to the lungs and form bubbles, which can lead to clogging of blood vessels and serious disease. Therefore, astronauts need to absorb pure oxygen before leaving the cabin to discharge nitrogen in the body to avoid hidden dangers.
When the spacewalking astronauts orbit the Earth at high speed, there is no reference object in the vast space, and they cannot distinguish the size and speed of the object. If there is no insurance measures, they may be lost in the vast space and become human satellites. In addition, the manned spacecraft and themselves are in motion, and the astronauts can sometimes be confused and potentially dangerous, so the space walk needs to take insurance measures - wearing seat belts. The seat belt is like a baby's umbilical cord that connects astronauts to the spacecraft in case they get lost in space. On February 7, 1984, during the 11th flight of the U.S. space shuttle Challenger, astronaut Bruce McCandless wore a space suit with a booster device and walked freely in space for 95 minutes without wearing a seat belt for the first time, capturing the stopped working Solar Peak satellite and repairing it. After troubleshooting, it was returned to orbit. Bruce completed the first space shuttle mission to capture a satellite. The spacewalk also broke new ground for human activity in space. But for now, astronauts are still required to wear seat belts, just to be on the safe side. In case the astronaut can't walk back to the shuttle on his own, a tow cable can be used to pull him back.
Life in space may seem fun, but it's actually a test of astronauts' survival skills. It seems that it is not easy to be an astronaut and enjoy a different life from the earth people