What do astronauts need:

First of all, we must have good physical fitness, because astronauts have to overcome many difficulties in special environments such as mechanical environment, physical environment and narrow space environment when entering space or returning to the ground. In order to adapt to the test of this environment, the physical quality and comprehensive quality of astronauts are very important. Therefore, people lucky enough to become astronauts are rare. ?

One in a hundred?

Manned space activities have strict requirements for astronauts' physiology and psychology. According to the space mission and its different requirements for all kinds of astronauts, space medical experts formulate corresponding selection items, contents and standards. Generally, it includes basic qualification examination, clinical medical examination, physiological function selection, psychological selection, endurance and adaptability selection of special environmental factors, etc. The selection criteria and conditions for astronauts in different countries are basically the same, especially the requirements for physical fitness are the same. ?

There are many similarities between the selection criteria and methods of early astronauts in the United States and the Soviet Union. Astronauts are all selected from fighter pilots; The selection of astronauts is based on the selection of pilots; The required selection items are similar. The ratio of selection and elimination is about 1: 100. The first batch of seven astronauts in project mercury were selected from 500 military pilots. The first batch of 20 astronauts in the Soviet Union were selected from more than 3,000 pilots, and then 8 of them were eliminated. In fact, only 12 people participated in the flight. ?

From a gender perspective, astronauts are mainly men. Nearly 20 years after the first female astronaut, valentina tereshkova, flew,1August, 982, Soyuz T-7 spacecraft and female astronaut Svetlana Savika (34 years old) flew for the second time. At present, the number of female astronauts is gradually increasing. In terms of age, drivers and mission experts are generally 22-40 years old, and load experts can be over 40 years old. Because the former Soviet Union used spacecraft as the transportation system between heaven and earth, the age requirements for astronauts were strict, and fewer astronauts continued to fly over 50 years old, while many astronauts in the US space shuttle were over 50 years old. In terms of height, the astronauts' height is generally below 170 cm due to the small space of the return cabin of the former Soviet Union Soyuz spacecraft, while the cabin space of the American space shuttle is relatively large, and the height range of space pilots is wide, ranging from 162.5- 193.0 cm. ?

In order to ensure that astronauts have excellent physical fitness, the choice of physiological function is extremely critical. Physiological function selection is mainly to select those who have excellent basic physiological functions in human organ systems. Physiological function selection includes cardiovascular and pulmonary function examination, central nervous system function examination, auditory function examination, visual function examination, endocrine and immune function examination, etc. ?

The psychological and mental state of astronauts has a great influence on the completion of space missions, especially for long-term flights and multi-person groups, the selection of their psychological quality is very important. Astronauts live in a harsh, closed and isolated environment, and they also face unpredictable risks in space. In this environment, it is impossible to complete the prescribed tasks without extraordinary "strong nerves". ?

Psychological selection methods include psychological investigation and psychological conversation, personality psychological test, intelligence and cognition, and psychomotor ability. For a multi-person crew, special attention should be paid to the adaptability and coordination of astronauts. ?

In the process of space flight, we will encounter various special environmental factors, such as overweight, weightlessness, low pressure, hypoxia, high and low temperature, vibration, noise, radiation, isolation and so on. In the process of selecting astronauts, we should eliminate those who are sensitive to these special environmental factors and have poor tolerance, and select those who have excellent endurance and adaptability. ?

Strict vestibular function selection is also an important link in astronaut selection, which can effectively reduce the incidence of space motion sickness under weightlessness. ?

Space motion sickness, also known as space sickness, is caused by the inadaptability of the human body in weightlessness, which is very similar to the usual motion sickness and seasickness of ordinary people. At first, it was epigastric discomfort, and then there was pallor, sweating, dizziness, dizziness, nausea and vomiting, but the symptoms would be obviously alleviated after vomiting. Space motion sickness usually appears when a manned spacecraft enters orbit, and the symptoms disappear automatically after 2 to 4 days. However, don't think that space motion sickness is not a big deal. In fact, it is a big problem that is difficult to overcome for the development of manned space flight and space life science. ?

Due to the high incidence of space motion sickness, according to the data, nearly half of astronauts will suffer from this disease after entering orbit. The schedule of manned flight is very strict, and astronauts need to complete many important operations during this period after they are in orbit. If motion sickness occurs at this time, it will more or less affect the completion of its space mission, and even affect the safety of manned space flight in serious cases. Secondly, the onset of motion sickness does not have certain regularity. Although people who take part in space flight for the first time will suffer from this disease, it will also happen to some astronauts who have been in the sky for many times, which will have an impact on the original flight plan. ?

Therefore, vestibular function is related to astronauts' work efficiency, physical health and flight safety. The experience of the United States and Russia proves that strict selection of vestibular function is one of the effective measures to reduce the incidence of space motion sickness. Generally, swivel chair, swing or temperature stimulation to ear organs are used to check the sensitivity and stability of vestibular organs. ?

Can people who go into space by manned spacecraft be called astronauts? Otherwise! A manned spacecraft (such as a spaceship) must be an astronaut as long as 1 person. If a spaceship (such as the space shuttle) is carried by more than one person, the crew will be different. Some of them are spacecraft pilots, some are captains (or commanders), some are random engineers, and some are mission experts of manned spacecraft. These crew members should belong to the category of astronauts, or they are professional astronauts. In addition to the above-mentioned professional astronauts, there are also some astronauts who go to space to do scientific experiments, such as scientists, engineers and doctors. These people are called load experts and scientist astronauts, belonging to non-professional astronauts, but they all have specific space missions. In addition, some journalists, teachers, politicians or "tourists" have also been to space, but they can't be said to be astronauts, only space passengers. We classify people who go into space mainly because different people have different requirements for selection and training.