Feitian Dream has always been the dream of Chinese people since ancient times, and since thousands of years ago, ancient people have pursued Feitian Dream. It can be said that the flying dream of Chinese originates from the 5,000-year history and mythology of China. Six hundred years ago, a firearms master named Wanhu, in order to fly, held two large kites and lit 47 homemade rockets, while he tied a chair to the rocket and ascended to the sky with the rocket. It can be seen that flying is the long-cherished wish of China for thousands of years, even if it is crushed to pieces. Although the ten thousand households failed in the end, it also proved that the Chinese never lacked the courage to explore space, from the mythical story Chang'e Running Moon, to the flying sky of the Dunhuang murals, to the feats of the Ming Dynasty's ten thousand households, which is enough to show that the Chinese nation has been looking forward to the scenery beyond the sky since ancient times.
In order to realize the flying dream of the Chinese nation, Chinese has been immersed in the research and development of rocket technology, and is obsessed with the pursuit of manned spaceflight. In 1969, when the United States successfully landed on the moon, when Apollo first stepped on the surface of the moon and Armstrong left human footprints, a well-known saying was born: "This is a small step for me, but it is a big step for mankind." At that time, China could only look at the United States enviously, but since then it has worked harder to study manned space technology.
Until 2003, as China's first astronaut, Yang Liwei successfully entered space and realized the Chinese nation's dream of manned aviation. Shenzhou No. 5 lifted off and Yang Liwei successfully landed on the moon, which has epoch-making significance for the Chinese nation and even the world, and is also a milestone in China's flying dream.
The successful moon landing of Shenzhou V and Yang Liwei has attracted the world's attention, and they have also successfully focused the world's attention on Yang Liwei. Everyone is very concerned about what Yang Liwei saw in space? What did you hear? Of course, everything cannot be implemented until Yang Liwei successfully returns to Earth. Not only to successfully achieve the lunar landing plan, but also to successfully return to Earth from space. So Yang Liwei's return to Earth is even more remarkable.
But when he did not expect to return to Earth, Yang Liwei encountered a trouble. At that time, Yang Liwei was still floating in space, but there was a problem with the spacecraft's thermal insulation layer. If the insulation had been completely destroyed before he returned to the ground, it would mean that Yang Liwei would disappear into space with the spacecraft. This poses a great threat to Yang Liwei's life safety.
Because the pressure in space is completely different from the ground, and the spacecraft in the process of high-speed driving and the air produces violent friction, and friction will cause the spacecraft to generate huge heat, if there is no barrier of the insulation layer, then Yang Liwei will be evaporated by the high temperature of up to more than two thousand degrees instantaneously. This made everyone who was in the ground console at the time sweat a little. If the insulation layer is really burned, then it means that Yang Liwei's space trip has never returned. Fortunately, Yang Liwei eventually successfully returned to Earth and realized the last link of the manned spaceflight program.
But after Yang Liwei returned to Earth, he said something that made everyone feel creepy. Under the extremely urgent situation at that time, Yang Liwei heard a knock on the door from outside the spaceship, and the knocking sound was very regular. It's like someone knocking on the door outside, but the problem is that the situation that is commonplace on Earth becomes strange in space, and there is no one in space, so why is there a knock at the door? Could it be that there is an unknown object outside the spacecraft?
Due to the urgency of the situation at that time, Yang Liwei did not have the energy to think too much, and he forced himself to calm down as soon as possible to deal with the problem of the spacecraft's thermal insulation layer. Thanks to the previous rigorous training and excellent physical and psychological qualities, Yang Liwei successfully operated the spacecraft and returned to the ground safely under such an urgent situation.
When Yang Liwei stepped out of the space capsule, countless cheers and flowers came from all directions, as China's first astronaut Yang Liwei paid great courage and dared to fight hard in the unknown future.
However, for the knock on the door that Yang Liwei heard at that time, because only Yang Liwei heard it, the statement of this knock has not been qualitative. It wasn't until 17 years later that scientists finally gave a reasonable explanation, it turned out that due to the damage to the thermal insulation layer, the temperature directly affected the pressure. Under the influence of huge pressure, the external structure of the spacecraft was squeezed. The so-called knocking on the door that Yang Liwei heard was most likely due to the sound of damage and fragmentation of the spacecraft components.
In the quiet situation at that time, this sound would be infinitely amplified, so it would give Yang Liwei the illusion that someone was knocking on the door. Hearing this explanation, everyone put down their infinite reverie and believed that higher science and technology in the future could explore more space knowledge.