Danger: The adverse effects of weightlessness are great. In addition to the loss of astronauts' bones, weightlessness will also lead to relaxation of astronauts' muscles, decreased immunity and aging. It has caused all kinds of space motion sickness, which has occurred frequently in the history of manned space flight in recent 20 years. The following figures are enough to illustrate this point: the incidence rate of astronauts on the Ascension Spacecraft of the former Soviet Union is about 60%, that on the Salute Space Station is 40%, that on the Apollo Spacecraft of the United States is about 37%, that on the Skylab is 55.5%, and that on the Space Shuttle is 53%. It can be seen that space motion sickness is an urgent problem in the aerospace field. Weightlessness will change the distribution of water in human body. Due to the loss of gravity, the distribution of facial water will increase, and there will be eye socket swelling, facial edema, eye thickening, wrinkles disappearing, plasma volume decreasing, intracellular fluid's body loss and other phenomena. Weightlessness can also change the function of blood vessels in the human body. The specific changes are as follows: 1. Decreased heart function. For example: myocardial mass decreased, contractility decreased and so on. 2. Pathological changes of human myocardium; 3. Changes of coronary artery and coronary microvascular structure, congestion and bleeding of capillaries, swelling and rupture of vascular endothelial cells; 4. Biochemical changes of myocardium, such as decreased protein synthesis, lipid accumulation, increased myocardial collagen, decreased norepinephrine and decreased potassium and sodium ions; 5. Aorta and abdominal aorta have obvious intimal hyperplasia, lipid deposition, capillary atrophy and endothelial cell swelling; 6. The fullness of human upper limb organs and tissues increases, while that of lower limb veins decreases. Working in weightlessness for a long time will make the blood supply in the cerebral hemisphere asymmetric (right ascending and left descending), but what about the immune system? Our bodies have been attacked by microorganisms. Such as bacteria, viruses, some protozoa and so on. Generally speaking, these microorganisms will not cause harm to the human body, and even some bacteria are beneficial to the human body. The immune system protects the human body. The function of human immune system is mainly attributed to various immune cells, among which B lymphocytes and T lymphocytes are the most important. B lymphocytes can secrete antibodies, prevent the invasion of pathogens and mark pathogens, while T lymphocytes kill pathogens. But in space, these two kinds of cells are not so "diligent". For example, T lymphocytes can't proliferate well in space, and the number is much less than that on earth. And the migration in the body and the communication signals between them are also abnormal. Thereby greatly reducing the ability to resist foreign pathogenic bacteria. [2]

Daniel Pearson of the Center for Microbiology Research at the Johnson Space Base in the United States said that the tiny liquid coughed by astronauts contained 8 to 10 times as many pathogenic microorganisms as normal people on Earth. This is mainly because of weightlessness and other reasons, so that the hormone release in the body is abnormal, thus affecting the performance of T lymphocytes. Some are bone loss. We usually think that bones are rigid and unchangeable, but this is not the case. Bone is also a kind of tissue. Their metabolism is busy, and their shape will change because of the change of stress. There are both osteoclasts and osteoblasts in bone tissue. Osteoblasts constantly store calcium phosphate, while osteoclasts are constantly removed. Usually, these two activities are balanced with each other. Once in space, gravity is almost zero, bones lack pressure, and the stimulation of osteoblast activity is gone, but the activity of osteoclasts continues. Therefore, the balance between osteoclasts and osteogenesis is destroyed, and bones are destroyed more and reconstructed less, which leads to the loss of bone materials and makes bones fragile. According to research, space tourists lose 1% to 2% of their bone weight every month. So far, no effective prevention method has been found. The study also found that radiation, weightlessness, adjustment of biological clock and mental stress in space will affect human reproductive ability in space. Male sperm chromosomes will be affected and developing embryos will be destroyed. Because weightlessness and radiation can cause endocrine disorders in men and women, it is easy to cause infertility, and even if normal delivery can be achieved, the health of pregnant women and fetuses is difficult to be completely normal. The loss of calcium will lead to osteoporosis in pregnant women, and the drastic change of calcium in the fetus will cause convulsions and even death in newborns. How to strengthen radiation protection equipment in space, strengthen human bones and regulate the endocrine system of men and women is a difficult problem that must be overcome to realize the dream of space immigrants. In addition to the above important effects, weightlessness will also affect people's taste. So astronauts generally complain that eating in the sky is tasteless. That's because weightlessness in space leads to astronauts' taste disorders, such as nasal congestion caused by weightlessness, which leads to dulling of taste nerves and changes in saliva secretion. Mammals cannot reproduce normally in weightlessness. A research result published by a research team jointly established by Japan Institute of Physical Chemistry and Hiroshima University in the American journal PLoS One published on August 25th, 2009 pointed out that on the International Space Station and the Space Shuttle, this result shows that it may be difficult for human beings who are also mammals to reproduce in space. Wakayama Akihiko, head of the research team of the Comprehensive Research Center for Generation and Regeneration Science (Kobe City) of the Institute of Physical Chemistry, said, "By investigating how much gravity is needed for the development of fertilized eggs, we may know the possibility of cultivating offspring at the lunar base." The researchers used a special device to create a microgravity environment of one thousandth of the ground gravity by rotating the experimental container, and investigated its influence on in vitro fertilization and delivery of mice. The results show that although fertilization can be carried out normally, during the division of fertilized eggs, the number of cells gathered on one side of placenta is less than usual, and the development speed is slower. After injecting it into the uterus of female rats, they can give birth normally, but the birth rate has dropped by nearly half. Previous space experiments show that fish and amphibians can develop normally in space. The research team believes that "this situation may be caused by the unique placental development of mammals related to gravity." The scientific law of weightlessness, the weight of an object comes from gravity, Newton's law of universal gravitation, and expounds the effect of the earth's gravitational field on all substances. In the cosmic galaxy, all planets have gravitational fields. The word "weightlessness" means that matter has lost the power of gravitational field. For example, human beings are out of gravity in space, the weight is equal to zero, and all substances are floating. The gravity of matter is relative to gravity. The greater the density and mass of matter, the greater the relative gravity. Without gravity, all matter would be in weightlessness. In the five-dimensional space, time, gravity, microgravity, centrifugal force caused by high-speed operation of matter, gravity and weightlessness of matter will all produce relative quantitative changes/

Solution: Since 1957, when the Soviet Union launched the first artificial satellite, space technology has developed by leaps and bounds. Carrying satellites, spaceships and manned satellites have appeared one after another. The earth is surrounded by flowers of human wisdom, and we have begun to go out of the earth and conduct scientific research in outer space. Man boarded the space station for scientific research. From 65438 to 0982, the American space shuttle planted plant seeds in space and observed their germination and growth under weightlessness. It also takes all kinds of small animals into space to study their activities and development in weightlessness. The Space Shuttle Challenge was launched on April 6th, 1984. It carries 120 seeds of vegetables, fruits and flowers, including 1200 seeds of tomatoes. The effects of cosmic radiation on plant seeds and weightlessness on plant germination were studied. 1September 1992 12, the space shuttle Endeavour, carried 180 bumblebees, 7,600 fruit flies and 30 fertilized eggs, and conducted 19 biological experiments to observe their reproduction and habits in weightlessness. 1993 10 18 10 in October, the space shuttle Columbia with 48 mice was launched to study the adaptation process of mammals to gravity after returning from microgravity. There is also the 1 1 experiment, which takes the astronauts themselves as the experimental object to study the influence of space on the human body. People began to cultivate plants in space to see if plants still know the concepts of "up" and "down". Theoretically speaking, in the weightless environment of space, plus 24-hour sunshine, the conditions for plant growth are much superior to those on earth. Scientists predict that the space station can produce wheat grains as big as red dates and eggplant and pepper as big as watermelons. However, the result is disappointing. Why are plants so attached to gravity? According to Winter's biological theory, it can be explained that plants that have lived on the earth for a long time have formed unique physiological functions. When stimulated by gravity, the auxin content in the lower part of plant tissue will increase greatly, making the roots of plants grow downward and the stems grow upward. Once gravity is lost, auxin can't gather in the right place, so that young stems can't find the right growth direction, so they can only develop around in disorder and eventually lead to death. The space environment has many adverse effects on living things.

In space, only by imitating the gravity and load of the earth and strengthening exercise can we solve the problems of muscle atrophy, osteoporosis and decreased heart function. In order to solve this problem, the new space suit must have a device to supplement vitamins and ultraviolet radiation for the human body. In addition, air will not flow freely in space, and the ventilator must keep running. When treating fractures, Dr.> usually fixes bones with plaster, splint and bandage from the outside to keep them fixed. But there is an internal fixation technology in the United States that can be used in space, which is space surgery. The advantages of this technology are fast recovery, less pain, or even no pain, which is very suitable for space. The Swiss Institute of Internal Fixation and NASA are conducting a comprehensive study on this technology and training some surgeons. The establishment of space hospital is also a very important aspect. It is not only responsible for psychotherapy, but also studies how to ensure the life safety of astronauts, including how to take physical preventive measures, such as exercise, electrical stimulation, lower body negative pressure, protective clothing and so on. , but also research drugs used for clinical treatment and prevention in space. The task of space pharmacology is to find effective drugs to normalize blood redistribution, eliminate some blood circulation phenomena in small circulation and cerebral blood circulation, prevent the disorder of heart activity and improve standing endurance. Among them, it is particularly important to develop drugs to prevent and treat arrhythmia, cardiotonic agents, drugs that affect myocardial energy reserve, and drugs that regulate vascular tension. Of course, the fundamental solution is to try to establish a special environment similar to gravity. In this regard, we imagine that centrifugal force can be used: people live in a rotating wheel, and the support of the wheel wall forms a centripetal force. People have pressure on the wheels. This is similar to gravity on the earth. As long as the appropriate wheel radius and speed are selected, a force similar to gravity can be generated. Can people feel dizzy living in such an environment? This is possible, because: people are tall, so the radius of rotation of the head and feet will be different, so the centripetal force will be different, which may cause physical discomfort and dizziness. But this problem can be completely solved. We analyze that to reduce this feeling, we must reduce the centripetal acceleration gap between head and feet.

There is another question: how can we make the wheels turn when we are helpless in the universe? According to the law of conservation of momentum, two wheels are used to rotate in opposite directions. First, a motor can be installed in the center of two wheels, one connected to the stator and the other connected to the rotor. When the motor is started, the two wheels turn in opposite directions. When it reaches a certain speed, the motor is turned off and the wheel can rotate forever. (regardless of resistance)

In this way, human beings can not only work in weightlessness environment, but also live in simulated gravity environment, which will make scientific research and production activities in space more lasting and achieve better results. Imagine that people living in this environment are exactly the same as those living on the earth. When they jump, they will fall, water will flow downwards, eagles will hit the sky, fish will swim underwater, and even human gravity can be adjusted. As long as the speed is adjusted to change the centripetal acceleration (similar to the acceleration of gravity on the earth), people can also carry out fitness activities in that environment. Building a football field in space is also feasible in theory. When people play football, the acceleration of gravity decreases, athletes can jump higher and run faster, and the game will be more exciting. How nice it would be! We firmly believe that only by establishing such an environment can mankind make large-scale use of space.