From ancient times to the present, human beings are full of infinite yearning for the moon. I dream that one day I can go into Guanghan palace and drink under the osmanthus tree with Chang’e and Wu Gang. After thousands of years of hard work, human science and technology can finally realize the wishes of our ancestors. Since Apollo landed on the moon, the world’s major powers are no longer satisfied with the exploration of the earth, and have turned their targets to space. They raced into space to take the lead in acquiring new resources. From scratch, the Chinese people grope step by step, from zero base to stable in the forefront, behind which there are countless people’s wisdom and sweat. < / P > < p > in the eyes of many people, it may be very easy to go into space. However, it is very difficult to develop a manned spaceship. Apart from that, astronauts also need to overcome the pressure brought by the resonance between spacecraft and rocket. In order to successfully enter space, astronauts have been training repeatedly for ten years. In addition, in the process of human leaving the earth, there will be some strange phenomena that cannot be explained. For example, astronaut Yang Liwei once encountered a knock on the door of a space capsule from time to time. Aerospace technology is a very complex system engineering. If we want to complete this idea, we must constantly overcome various technical difficulties. It is not only a sign of our country’s strength, but also an important process of promoting the development of the whole human race. Since it is manned space flight, it must be in line with the safety and freedom of human access to space, so the safety of astronauts has become a very important issue. On manned spaceflight, Newton was the first to put forward this idea. In a book, he boldly put forward an idea: “suppose there is a cannon on the top of a very high mountain. If there is no gravity and air resistance conditions, the projectile should be fired in a straight line away from the earth. A seemingly ridiculous idea became the earliest idea of spaceship. On April 12, 1961, the Oriental rocket rose from the Baikonur rocket launch base, and the astronaut’s name was Yuri Gagarin. At that time, people thought that as long as Gagarin could come back alive, he would surely usher in an unparalleled honor. Because as long as the rocket in the space field fails to launch, it means the end of the fate of astronauts. Fortunately, Gagarin did it and became famous. Yuri Gagarin became the first person to enter space in history. In order to commemorate him, human beings called April 12 international space day. < / P > < p > “a successful flower is only admired for its brilliance when it is in full bloom. No one knows that when it sprouts, it is soaked with the tears of struggle and the blood rain of sacrifice. China’s space industry began in 1956, and countless people have paid blood and tears for it. As China’s first man to enter space, Yang Liwei has countless heartaches behind him. Yang Liwei once said that from the day he became sensible, he always had a flying dream in his heart. Because my family lives by the sea, I dream of flying into space. In his childhood, Yang Liwei was thin and weak, and his personality was introverted. In order to change his character, his father decided to take him to some collective activities. Yang Liwei slowly developed a desire for the unknown. Yang Liwei’s father also paid a lot for such achievements. In his third year of high school, the unit recruited pilots, which also let Yang Liwei see the opportunity. After a series of selection, Yang Liwei successfully entered the ranks of recruits. Those who work hard are only waiting for opportunities. In 1995, the state decided to build a manned space project. Because of the importance of such projects, it was decided to train a number of astronauts directly from the air force in advance. In 1997, Yang Liwei officially became a member of the space engineering. Until 2003, Yang Liwei was awarded the title of class III astronaut. After the Shenzhou V spacecraft was ready, Yang Liwei also took the spacecraft into space, becoming a hero in the eyes of the people of the whole country. < p > < p > Yang Liwei not only has great national honor, but also bears the great risk of Chinese people’s first space flight. After the launch, everyone was focused on the whole journey. After all, the universe is a vast unknown “wasteland” for human beings. It is full of too many uncertain factors. A little mistake will bring irreparable loss. Therefore, no one can guarantee that this flight is 100% safe, and Yang Liwei also understands. After successfully entering space, Yang Liwei was always careful. After everything is stable, Yang Liwei hears the sound of “bang bang” from the normal operation of the spaceship. To ordinary people, it looks like someone is knocking on the window. Yang Liwei was not too surprised, and he calmly transmitted the phenomenon back to the land. Yang Liwei recalled that when he was training on land, the book recorded that Soviet astronauts had also encountered such situations. There is no answer to the specific reasons. In order to ensure the completion of the mission, Yang Liwei can not rashly take measures, allowing the “guests” in space to knock on the door. < p > < p > things have been going on for so many years, and finally scientists have found the truth of “knocking on the door”. The so-called “knock on the door” sound is not from the outside world at all, but is produced by human beings themselves. Because the universe is different from space, the spacecraft needs to bear huge pressure changes in the state of vacuum. In this case, the internal structure of the spacecraft is prone to “deformation”. It is the very weak change of the spacecraft that makes the “bang bang” sound. As an astronaut in outer space, due to high mental tension, it will be mistaken for “knocking on the window”. < / P > < p > since it is the case of the spaceship under the pressure, if the Spacecraft flies for a longer period of time, it is likely that unimaginable things will happen. As a result, many astronauts, including Yang Liwei, said in an interview that they “really recovered a life.”. Today, the major countries have made a qualitative leap forward in space technology, and this risk will not happen again. Continue Readinggather and watch! Huawei P40 Pro evaluation: excellent mobile phone photography elegant design, do you like it?