If you don't know the time in advance and when the bus will arrive, you can only wait there, which is ok, but it consumes your time.
The same is true for the launch of Shenzhou 12, which was launched by scientists at this time. After the launch, our space station just reached the best position, and naturally it can dock in the shortest time.
Of course, there are also many technical contents, such as automatic unmanned docking technology. Now there are three astronauts on board, and the speed and accuracy of docking can be greatly improved by unmanned and manned ways.
At 9: 22 am on 202/KOOC-0/June/KOOC-0/7, the Long March II F rocket with a height of 58.34 meters was launched, carrying the Shenzhou/KOOC-0/2 spacecraft and three China astronauts into space and flying to the China Space Station.
At 9: 33, the rocket was successfully separated from the spacecraft, and the next step was the rendezvous and docking between the spacecraft and the China Space Station.
In fact, according to the established plan, the spacecraft can complete the rendezvous and docking with the China Space Station around 16 that afternoon, which lasted about 6.5 hours, not 7.5 hours.
Shortening the rendezvous and docking time stems from more advanced science and technology to examine China's space industry. Although it started late, it made rapid progress.
China Space Station (Tiangong Space Station, English name: Chinese Space Station) refers to the space station system planned by the people of China.
The orbital height of the space station is 400-450km, the inclination angle is 42-43 degrees, the design life is 10 year, three people stay for a long time, and the total weight can reach 90t, which can be used for large-scale space applications.
From 65438 to 0992, the government of China formulated a "three-step" development strategy for manned spaceflight project, and building a space station was an important goal of the development strategy.
At first, due to technical and experience problems, the rendezvous and docking time was longer.
On June 1 1, 2065438, Shenzhou 10 was launched, and on June 13, Shenzhou 10 docked with Tiangong-1 Space Laboratory.
20 16,10,65438, Shenzhou XI launched, 20 16,/kloc-0,65438, Shenzhou XI and Tiangong-2 realized automatic rendezvous and docking.
These two times basically took almost two days to complete the rendezvous and docking work, which was relatively long in general.
However, Shenzhou 12 has been fully upgraded, not only using the latest chip technology, but also using the extremely accurate Beidou navigation system as the "eye", which greatly shortened the rendezvous and docking time.
Many people know that simply walking in a straight line is the shortest distance between two points. The reason why the rendezvous and docking time can be compressed to about 6.5 hours is actually to make maximum use of this simple truth.
The space station is located in a fixed orbit in space, and it moves along the orbit, which is the same as the earth going around the sun.
The speed of the space station is still very fast. Officially, it is called the orbital period (usually marked by the Greek letter 19), and the length of time is related to the orbital height of the space station.
If the actual height of the space station is about 500 kilometers, that is, 3 12 miles, it is estimated that the time for the space station to circle the earth is 94.56 minutes, which is still very fast.
The rendezvous and docking between the spacecraft and the space station is generally understood as sending the spacecraft to the orbit of the space station with a rocket, and then the spacecraft needs to move synchronously at the same "speed" as the space station.
When they are at the same speed and plane, the spacecraft and the space station are in a relatively static state. The space station stretches out the docking "arm", pulls the spacecraft to its side and connects the docking interface, and the docking work is completed.
Then the principle of maximizing compression time in theory is to calculate the shortest distance between the spacecraft and the space station when it reaches orbit, that is, the linear distance between the space station and the spacecraft is the shortest in theory.
Because the earth itself is not a sphere, the orbit of the space station is irregular, and the earth rotates, you know why the launch time is accurate to seconds, which is the result of strict calculation.
The main task of Shenzhou XII is to further verify the functional performance of manned space transportation system.
The improved Long March 2F carrier rocket has improved the reliability and safety, and the Shenzhou-12 manned spacecraft has increased the autonomous rapid rendezvous and docking, radial rendezvous and docking and 180-day on-orbit docking capabilities. The return technology has been improved, the landing accuracy has been further improved, and the emergency rescue mission mode of manned spacecraft will be started for the first time.
Second, it will fully verify the long-term stay guarantee technology of astronauts.
After working and living in orbit for three months, the Shenzhou-12 astronauts checked and verified various support technologies for astronauts' long-term space flight, such as regenerative life support, space station material supply and astronaut health management.
The third is to verify the ability of astronauts and robotic arms to complete extravehicular activities and operations in orbit.
With the support of the mechanical arm, the astronauts will carry out long-term extravehicular activities for the first time, and carry out equipment installation and maintenance outside the cabin.
Fourth, the search and recovery capability of Dongfeng landing site will be tested for the first time.
The landing site was adjusted from Siziwangqi, Inner Mongolia to Dongfeng landing site, and the normalized emergency standby search and rescue mode of the landing site system was opened for the first time.
As the first manned flight built by China Space Station, the Shenzhou-12 mission is very important.
The mission lasted for three months, which coincided with the 0/00th anniversary of China * * * Production Party/KLOC. I wish Shenzhou XII and the three astronauts a successful completion of their scheduled work, which will add more glory to our space cause and contribute to the centenary birthday of the Party!
Our space station is only 350 km to 450 km away from the earth, which is very close. If Shenzhou 12 doesn't detour, it will arrive in a few minutes. When the spacecraft meets the space station, it must go around slowly and then meet. 7.5 hours is neither slow nor fast.
Shenzhou spaceship successfully ascended to heaven again, showing the world our strength. The manned spaceflight project was directly docked after a short adjustment, and our three astronauts were sent to the space station. This shows that our space technology is mature and very skilled, so we can finish these difficult things in a short time.
In recent decades, especially in recent years, China's space science and technology has developed rapidly, which has shocked the world. From our manned space flight to the construction of the space station, from the launch of the lunar exploration satellite to our current Mars exploration, from being rejected by the satellite positioning system to having our own Beidou satellite navigation, all this was done alone in more than 20 years.
Without any country's participation and other help, it is entirely up to us to do it step by step. Up to now, we have become the top three space powers in the world, leaving those countries that have closed their doors to us far behind, and letting them understand that the blockade can't stop us from moving forward. Only by actively cooperating with us can they have a chance to develop, otherwise they will be left behind in the end. After a certain time, they can't even see the taillights.
Especially in recent years, the successful return of lunar exploration samples, the arrival of Beidou navigation, the start of space assembly of the space station and the successful landing of the Mars probe are all dazzling. Even as citizens, we all feel that the speed is really too fast. Foreign countries are watching our achievements come true step by step over the years, but their plans are still just plans and have not even been implemented. This is the difference and gap.
At the same time, it also makes some people feel sour from the top of their heads to the bottom of their feet, because their own plans are just empty slogans, but we have realized all the plans one by one. Originally, we were behind them, but now we are far ahead, which makes them simply unable to accept such a result. Their fragile hearts completely collapsed and they could not make their own efforts. They can't accept the fact that what they once looked down upon is far ahead of themselves. Finally, I can only vent my sour doubts.
Why are we making such rapid progress? The reason is that our investment in scientific research is not comparable to that of ordinary countries. In addition, we dare to use young scientists with innovative ideas boldly. The main force of our aerospace science and technology is now the 8090 team. They are very young, full of energy and dare to try all kinds of difficult things. Of course, these are all based on our rigorous attitude and reasonable planning, step by step, not to do exaggerated things, but to do things that are reasonable and sure.
We have accumulated rich experience for a long time, which also enables us to successfully carry out various plans in a short time, which is the result of the efforts of generations of researchers. Because of our unified cultural charm and unified coordination, this is far from being comparable to other countries. The secret of success is down-to-earth unity and cooperation, as well as dedication and great investment. It is hard to ask who else can be like us, so it is hard to fail.
First, the take-off time should be accurate to seconds in order to accurately control the orbit of the spacecraft.
Second, the successful application of Beidou navigation system makes navigation more convenient. Just like driving a car, if you have a navigation plan in advance, you will drive, have a direction, and know when to change lanes and turn, so as to be unimpeded. )
Third, the previous rendezvous and docking was controlled by ground survey and remote sensing. Now autonomous control in the air is realized directly by navigation and a series of optical devices. That's what we often call AI technology, similar to artificial intelligence.
Fourth, the most important thing is China engineers' fearless spirit of exploration and their ability to keep improving. China speed covers developed countries in 20 years 100. It is our generation of young people who now have the strength and are not afraid of working overtime. Don't stop until you get what you want.
Use the shortest flight distance.
Explain that the technology is mature and advanced. Going to the space station in the future will be like going home. Decades of accumulation have finally begun to bear fruit, and China has accumulated a lot of science and technology. Looking back on the blockade of China by the International Space Station in 1990s, China can now go to its own space station, which shows that advanced technology cannot be bought. Only by developing our own capabilities and attaching importance to the cultivation of high-end scientific and technological talents can we get rid of the American blockade. And surpass the United States.
Dinner has been left behind.