Aerospace terminology
Aerospace is also called space flight or space navigation. "Aerospace" generally refers to the navigation activities of spacecraft in space outside the earth's atmosphere (including within the solar system), and is roughly divided into two categories: manned spaceflight and unmanned spaceflight. "Aerospace", a new thing in the long history of mankind, uses many nouns involving basic concepts, which are very different from "aviation".
Life in spaceflight
The space environment is extremely harsh. The main factors harmful to the human body are high vacuum, high hypoxia, cosmic radiation, temperature differences, etc. These adverse factors will have harmful effects on the human body. causing serious injury. In this environment, astronauts cannot survive and work. Facing the severe space environment, how can we ensure the safety of astronauts? Our scientific and technical personnel developed a closed environment that is basically isolated from the outside world, that is, a closed cabin to protect the astronauts.
Sometimes it is morning, sometimes it is night
People's long-term living habit is to "work at sunrise and rest at sunset", and sleep is generally arranged at night. The day and night cycle of a spacecraft during spaceflight is different from our day and night cycle on Earth. A day on Earth is a sunset and a sunrise, and is measured in 24 hours. A sunset and sunrise period during space flight has different lengths because it is related to the height of the spacecraft's orbit around the earth. When the orbit is high, the day-night cycle is long; when the orbit is low, the day-night cycle is short. During the space flight of the spacecraft, the length of day and night is inconsistent. The day and night are long and the night is short. There is a day and night cycle of 90 minutes, and the longest night is only 37 minutes. When the spacecraft passes from the sunny side of the earth to the dark side, it is like going from day to dusk and night. The space shuttle is very fast. When the sun rises, it jumps out like a "thunder", and when the sun sets, it disappears as quickly as a "whirlwind."
An astronaut once described a day in the universe this way: In the morning, the computer-controlled clock wakes us up. I woke up and opened the curtains to look at the universe. The sun was shining brightly and the sky was so beautiful. But after a while, the sun disappeared, the sky darkened, and night came. We thought it was time to sleep again. It’s really interesting, sometimes it’s morning, sometimes it’s night...
It’s the same whether you sleep standing up or lying down
The most special thing in the universe is the sleeping posture. When weightless, the body Complete relaxation creates a natural arched posture. Aerospace experts believe that sleeping in space is much more comfortable with the body slightly bent into an arch shape than lying flat on the back completely straight.
When astronauts fly in space, their sleeping bags are usually fixed to the bulkhead inside the spacecraft. If not, the posture inside the spacecraft may collide with the bulkhead when the engine is started. Therefore, astronauts generally prefer to sleep with their sleeping bags close to the bulkhead, so that they are as comfortable as sleeping on a bed. In weightlessness, you can't tell the difference between up and down anyway. It doesn't matter whether you sleep standing up or lying down. Therefore, astronauts can sleep against the ceiling or stand upright against the wall. They can sleep however they want.
Since people float when weightless, astronauts will find it difficult and inconvenient to move, and their movements will not be as coordinated as on the ground. He is unsteady and swaying when sitting upright. He may turn over when he raises his head and leans back, and he may do somersaults when he bends down, so all movements must be done carefully.
Astronauts can look at the earth's scenery during spaceflight, which is also one of the great pleasures of their space life. Since ancient times, flying into space has been mankind's best fantasy. The earth that the astronauts saw from the spacecraft was extremely beautiful. It was a green sphere. When you look carefully during the day, most of the earth is light blue, and the dense forests look even bluer. The only real green area is the Tibetan Plateau in China. Some mountain lakes look bright and bright green, like the color of copper sulfate mines. In areas where the temperature is very low and there are no clouds, such as high mountain areas like the Himalayas in my country, you can clearly see the landforms there.
The most dazzling spectacle that astronauts can see is the Kavir Salt Desert in Iran. This desert looks like Jupiter, with a large red, brown and white vortex in the middle. This is Because of the dazzling traces left by the salt lake after generations of evaporation, it sparkles like emeralds.
Inseparable from physical exercise
Astronauts living in space also cannot do without physical exercise. In addition to enhancing physical fitness, it also has special significance: enhancing the ability to adapt to weightlessness and other aerospace environments, and reducing the harmful effects of adverse environments on astronauts during spaceflight. In long-term space stations, there are "small stadiums" specially designed for astronauts' physical exercise, and some special space sports equipment are set up for astronauts to use. These devices include bicycle dynamometers, mini-tracks, spring tensioners and negative pressure cylinders.
Astronauts sailing in the space, like people on earth, need to perform personal hygiene, such as brushing teeth, washing face, bathing, defecating, etc. Handling sanitation and waste under weightless conditions is very complex and requires special facilities and skills.
When brushing your teeth in weightlessness, the toothpaste foam will easily float, and water droplets will fly in the cabin, which will affect people's health and the normal operation of the equipment. Astronauts in the spacecraft cannot use the brushing tools and methods on the ground. If you do that, the water may leak out at some point and the water will float. Therefore, the astronauts can only use a relatively simple way to brush their teeth. The United States uses a special gummy candy that allows astronauts to chew it thoroughly instead of brushing their teeth to achieve the purpose of cleaning their teeth. When astronauts wash their faces, they actually scrub their faces with a wet towel soaked in cleaning care solution. Then, lay a towel over the massage brush and use it to comb your hair.
If astronauts live on the space station for a long time, they will also need to take a shower. Long-term manned space stations are equipped with aerospace bathroom facilities designed and produced by aerospace engineering and technical personnel. This kind of bathroom is nothing more than a strong nylon cloth bath cover. The bath cover has a fixed frame at the top and bottom. The upper part is connected to the ceiling and the lower part is connected to the floor. It becomes a sky-high closed bath cover. It is usually folded and fixed on the ceiling of the living cabin. There is also a circular water tank, nozzles, and electric heaters on the ceiling. The water tank for bathing is connected to the large water tank by pipes.
Before taking a bath, first prepare the purification adsorbent in the wastewater recovery and purification device to prepare it for recycling and purifying the sewage during bathing, and then clean the water supply pipeline, water pumping device and filtration and purification device (to remove impurities and bad smell), and lower the nylon cover rolled on the ceiling until it reaches the bottom frame and fix it, forming a barrel connected to the ceiling floor, just like a completely transparent large glass cylinder. Start the electric heater to heat the water in the water tank to a suitable temperature. At this time, people can take off their clothes and enter the bathroom. There is a pair of fixed slippers at the bottom of the cylinder so that people will not float after putting them on. Before opening the faucet, the respirator should be put on first. The respirator is connected to a hose that leads to the outside. The astronauts can breathe the air in the cabin to avoid the danger of the air and water vapor mixture being inhaled into the respiratory tract during bathing. When astronauts take a shower, they have to plug their ears and wear goggles, just like divers. After everything is ready, you can open the faucet and a thin stream of water will spray on your body, forming a layer of water film with countless bubbles. The water must be sucked away with a towel or absorbent brush. Water will not flow out automatically when there is weightlessness. If there is air pressure in the water tank, the water will flow out continuously.
The handling of astronauts’ urination and defecation on board the spacecraft is also quite scientific. The urinal is specially made. The toilet is connected with a plastic sleeve. After defecation, the rubber valve is quickly closed. The stool falls into the breathable stool collection bag through the air flow, and then is sealed with a sealing bag and put into the toilet. When the toilet is full, it will pop up automatically. outside the cabin.
This is the special daily life of astronauts. Isn’t it really amazing?
Aerospace: refers to artificial earth satellites, spacecraft, etc. flying in the space near the earth or in the solar system.
In today's situation of rapid development of science and technology, reference books always seem to be relatively old or have vague and inaccurate definitions. Although there are partial modifications to follow the development of the situation, conflicts often arise.
In modern natural science, "universe" adopts the second explanation mentioned above. In layman's terms: the universe is the sum of space and time. Our ancestors had a correct understanding of the universe long ago. The ancient book "Huainan Qi Su Xun" of the Han Dynasty said, "The four directions, up and down, are called the universe, and the past and present are called the universe." Zhang Heng, a famous astronomer in the Han Dynasty, said: "The surface of the universe is infinite, and the end of the universe is infinite."
With the development of science and technology, the requirements for the division of space and time are becoming more and more precise.
In ancient times when productivity was low, it was enough for people to divide time into months, days and days. Later, it became more convenient when I was asked to distinguish hours or hours. The rise of modern industry and transportation such as trains, automobiles, and airplanes further requires the division of minutes and seconds. For modern science and technology, this is not enough, but also requires milliseconds, microseconds and nanoseconds to be used for timing.
The same is true for the division of space. In ancient times, it was enough to have the concepts of sky, space and ground, but it was far from meeting the requirements of modern science and technology. Especially after the birth of aerospace technology, it was required to strictly distinguish between "sky" and "empty". "Sky" refers to the vast space outside the earth's atmosphere. This is roughly equivalent to "sky" and "space". I say "roughly" because if the sun, moon and stars do not include the earth, and "sky" exists only outside the earth's atmosphere, then "sky" is space, and "space" is generally speaking of "the extremely high sky". There is no precise physical properties.
"Empty" refers to the atmospheric space above the earth's surface.
According to the above classification, should "weather", "weather forecast" and "starry sky" be called "air", "air forecast" and "starry sky"? But there is a conventional question here , no modification is required and there will be no ambiguity. Similarly, the term "space science (technology)" currently used should also be called "space science (technology)". If the term "space" is too vague, another customization process will be required. Aerospace: refers to the flight of artificial earth satellites, spacecraft, etc. in the space near the earth or in the solar system.
In today's situation of rapid development of science and technology, reference books always seem to be relatively old or have vague and inaccurate definitions. Although there are partial modifications to follow the development of the situation, conflicts often arise.
In modern natural science, "universe" adopts the second explanation mentioned above. In layman's terms: the universe is the sum of space and time. Our ancestors had a correct understanding of the universe long ago. The ancient book "Huainan Qi Su Xun" of the Han Dynasty said, "The four directions, up and down, are called the universe, and the past and present are called the universe." Zhang Heng, a famous astronomer in the Han Dynasty, said: "The surface of the universe is infinite, and the end of the universe is infinite."
With the development of science and technology, the requirements for the division of space and time are becoming more and more precise.
In ancient times when productivity was low, it was enough for people to divide time into months, days and days. Later, it became more convenient when I was asked to distinguish hours or hours. The rise of modern industry and transportation such as trains, automobiles, and airplanes further requires the division of minutes and seconds. For modern science and technology, this is not enough, but also requires milliseconds, microseconds and nanoseconds to be used for timing.
The same is true for the division of space. In ancient times, it was enough to have the concepts of sky, space and ground, but it was far from meeting the requirements of modern science and technology. Especially after the birth of aerospace technology, it was required to strictly distinguish between "sky" and "empty". "Sky" refers to the vast space outside the earth's atmosphere. This is roughly equivalent to "sky" and "space". I say "roughly" because if the sun, moon and stars do not include the earth, and "sky" exists only outside the earth's atmosphere, then "sky" is space, and "space" is generally speaking of "the extremely high sky". There is no precise physical properties.
"Empty" refers to the atmospheric space above the earth's surface.
According to the above classification, should "weather", "weather forecast" and "starry sky" be called "air", "air forecast" and "starry sky"? But there is a conventional question here , no modification is required and there will be no ambiguity.
Similarly, the term "space science (technology)" currently used should also be called "space science (technology)". If the term "space" is too vague, another customization process will be required.
[Edit this paragraph]China Aerospace
Shenzhou 5
From November 20 to 21, 1999, China's first manned space project " The flight test of the Shenzhou unmanned test spacecraft was a complete success. From the beginning of 2001 to the end of 2002, the Shenzhou 2-4 unmanned test spacecraft were successively developed and successfully launched, obtaining valuable test data and laying a solid foundation for the implementation of manned spaceflight. The Shenzhou-5 spacecraft is my country's first manned spacecraft developed on the basis of an unmanned spacecraft. It carries one astronaut and operates in orbit for one day. During the entire flight, the astronauts will be provided with necessary living and working conditions, while the astronauts' physiological data and television images will be sent to the ground to ensure the astronauts' safe return.
The spacecraft consists of an orbital module, a return module, a propulsion module and additional sections, with a total length of 8860mm and a total weight of 7840kg. The spacecraft's manual control function and environmental control and life support subsystems provide guarantees for the safety of astronauts.
The spacecraft was launched by the Long March-2f carrier rocket to an initial orbit with a perigee of 200km, apogee of 350km, and an inclination of 42.4°. After performing orbit changes, it entered a circular orbit of 343km. The spacecraft circled the earth 14 times and landed in a predetermined area.
The manned space flight of the Shenzhou-5 spacecraft has realized the Chinese nation's millennium desire to fly into the sky. It is a high degree of cohesion of the wisdom and spirit of the Chinese nation and a new milestone for China's aerospace industry in the new century.
Shenzhou-6
The Shenzhou-6 manned spacecraft is one of China's Shenzhou spacecraft series. There is no difference in appearance between "Shenzhou 6" and "Shenzhou 5". It is still a three-cabin structure with a propulsion module, a return module, and an orbital module. The weight is basically maintained at about 8 tons. It is launched with the Long March 2 F-type carrier rocket. . It is China's second spacecraft to carry astronauts, and also China's first manned spacecraft to carry out a "multi-person, multi-day" mission.
Shenzhou 7
Huang Chunping, member of the National Committee of the Chinese People's Political Consultative Conference, leader of the Manned Space Rocket System Advisory Group, and commander-in-chief of the "Shenzhou" 5 rocket, said that the launch time of the "Shenzhou" 7 It will be delayed by about half a year, and the launch plan originally scheduled for 2007 will be postponed to 2008. Unlike "Shenzhou 5" and "Shenzhou 6", the key points in the development of the "Shenzhou 7" rocket are the spacesuit and airlock. Because "Shenzhou" 7 will perform a space walk, the airlock and spacesuits will play an important role in whether the astronauts can suddenly adapt to the vacuum environment from the air pressure inside the cabin. Shenzhou 7 was launched at 21:10:04.988 milliseconds on September 25, 2008. The spacecraft successfully landed at the main landing site in Siziwang Banner, Inner Mongolia, China at 17:37 on September 28, 2008. The Shenzhou 7 spacecraft flew for a total of 2 days, 20 hours and 27 minutes.
At 14:30 on September 24, 2008, Wang Zhaoyao was accepted by the "Shenzhou 7" manned space mission at the press conference of the "Shenzhou 7" manned space mission headquarters at the Jiuquan Satellite Launch Center. The Commission of the General Headquarters of Human Spaceflight announced that it will be launched directly from 21:07 to 22:27 on September 25 to conduct manned spaceflight. At that time, Chinese astronauts will leave the capsule for the first time to conduct a space walk. At present, core technical difficulties such as the airlock cabin have been overcome, and the entire ship has entered the comprehensive testing stage. The Long March 2F rocket used to launch the Shenzhou 7 spacecraft is expected to complete the final assembly of the entire rocket by the end of December 2007. It is reported that the spacewalk during the "Shenzhou 7" spacewalk had higher requirements for astronauts' assessment. Because the pressure inside the space suit is lower than normal, nitrogen in human tissues may be released, forming air embolism in blood vessels, causing decompression sickness and even endangering people's lives. Therefore, after putting on the space suit, the astronauts must fully absorb oxygen in the airlock cabin. The astronauts who are assisting the work return to the inner cabin (i.e. the orbital cabin), close the inner cabin door, and then the airlock cabin begins to depressurize to a vacuum. It is consistent with the vacuum state outside the spacecraft. At this time, astronauts can move outside the spacecraft.
When returning to the cabin after completing the extravehicular mission, the spacesuit must be decompressed to a certain extent and then the airlock must be inflated.
"Astronaut extravehicular activity is a highly difficult and high-risk activity." Experts said that the spacewalk during the "Shenzhou 7" required astronauts to conduct sufficient testing and training on the ground. The ground training is usually carried out in a neutral pool with certain requirements for specific gravity. This kind of pool is usually built in a large test room. The spacecraft is placed in the pool and the buoyancy of the water is used to simulate the weightlessness phenomenon in space. Then the astronauts conduct training in and out of the cabin and extravehicular operations in the pool.
Zhang Qingwei, deputy commander-in-chief of China’s manned space program, said that the future Shenzhou-7 spacecraft will not be a simple repetition of Shenzhou-6 and will break through many key technologies. The Shenzhou-7 spacecraft will still be launched by the Long March 2-F carrier rocket. This rocket has successfully launched six Shenzhou spacecraft into space before and has a mature technical foundation. At present, the procurement and production of components for a new launch vehicle have begun. Rocket chief designer Jing Muchun said that this time they will use higher quality components. Based on the flight conditions of the first few rockets, scientific researchers will also make partial improvements to this rocket to further improve the reliability of the rocket. In addition, they are also considering adding some cameras to the rocket.
Starting from Shenzhou 7, our country has entered the second phase of the manned spaceflight project. During this stage, scientific goals such as astronauts’ extravehicular travel and space rendezvous and docking will be gradually achieved. All launch missions for the entire second phase of the project will be performed by the Chang-2F rocket.
[Edit this paragraph] What does the aerospace system include?
In October 1957, the world’s first artificial earth satellite Sputnik 1 was successfully launched in the former Soviet Union, ushering in a new era of human spaceflight. Space began to become a new frontier for human activities, and this year was designated as for the first International Year of Space. In the past half century, aerospace technology has made tremendous progress around the world. Aerospace technology has been widely used in many sectors of scientific activities, military activities, national economy and social life, and has had an extremely significant and far-reaching impact.
Aerospace refers to the general term for the entry, exploration, development and utilization of space (i.e. the cosmic space beyond the earth’s atmosphere, also known as outer space) and various activities of celestial bodies beyond the earth. Aerospace activities include three parts: aerospace technology (also known as space technology), space applications and space science. Aerospace technology refers to comprehensive engineering technology that provides technical means and guarantee conditions for aerospace activities. Space application refers to the general term for various application technologies that utilize aerospace technology and its developed space resources in the fields of scientific research, national economy, national defense construction, culture and education. Space resources refer to various environmental, energy and material resources outside the earth's atmosphere that can be developed and utilized by humans, including material resources at high and far locations in space, high vacuum, ultra-low temperature, strong radiation, microgravity environment, solar energy and celestial bodies other than the earth. .
Aerospace system refers to an engineering system composed of spacecraft, aerospace transportation system, space launch site, aerospace measurement and control network, and application systems to complete specific aerospace missions. The application system refers to the user system of the spacecraft, which is generally a ground application system, such as ground application systems for various satellites, ground application systems for manned spacecraft, and ground application systems for space detectors.
Aerospace systems can be divided into unmanned aerospace systems and manned aerospace systems according to whether they can carry people; they can be divided into civil aerospace systems and military aerospace systems according to their uses; they can be divided into many types according to the type of spacecraft. Such as satellite aerospace system, manned spacecraft aerospace system, lunar satellite aerospace system, etc.
The aerospace system is a modern typical complex engineering system. It has large scale, complex system, technology-intensive, strong comprehensiveness, large investment, long cycle, high risk, wide application and considerable social and economic benefits. With other characteristics, it is a national-level large-scale engineering system. To organize and manage the design, manufacturing, testing, launch, operation and application of aerospace systems, systems engineering methods must be adopted. Aerospace systems engineering has been formed in the practice of aerospace engineering, further enriching and developing the theories and methods of systems engineering.
A complete aerospace system is an important symbol of a country's aerospace strength and comprehensive national strength. Currently, only a few countries in the world have this kind of strength.
[Edit this paragraph] How many resources are there in space?
Space resources generally refer to the environment and materials that exist objectively in space and can be developed and utilized by humans. Mainly include: resources at high distances relative to the ground, high vacuum and ultra-clean environment resources, microgravity environment resources, solar resources, lunar resources, planetary resources, etc.
The resources available in space are much richer than those available on earth. In terms of the solar system alone, there are abundant mineral resources on celestial bodies such as the moon, Mars and asteroids; on Jupiter-like planets and comets, there are abundant hydrogen energy resources; in planetary space and interplanetary space, there are vacuum resources , radiation resources, large temperature difference resources, the efficiency of solar energy utilization there is much higher than on earth. Huge social benefits have been achieved so far. High vacuum and high cleanliness are distinctive features of outer space. They are an ideal environment for conducting many scientific experiments, developing aerospace technology, and producing electronic products and advanced pharmaceuticals. In particular, they are a prerequisite for human space activities. High vacuum and ultra-clean environment resources have achieved considerable practical results, but the utilization of microgravity resources and solar energy resources is still in the stage of experimentation, research and creation of conditions.