It takes only 6.5 hours for Shenzhou-12 and Tianhe to rendezvous and dock independently.

It takes only 6.5 hours for Shenzhou-12 and Tianhe to rendezvous and dock independently.

It takes only 6.5 hours for Shenzhou-12 and Tianhe core cabin to rendezvous and dock independently. Shenzhou 12 adopts 6-hour fast docking mode, which is much faster than most express delivery on earth. Why can it be so fast? So far, there have been more than 500 space docking around the world, most of which were carried out by the United States and Russia.

It takes only 6.5 hours 1 countdown for the rapid rendezvous and docking between Shenzhou 12 and Tianhe core module, and China will launch a manned spacecraft again! One of the highlights of the launch of Shenzhou XII is that it will adopt the fast docking mode, and it can dock with Tianhe 6 hours after launch!

Shenzhou 12 mission

On July 20 16 17, Shenzhou XI was successfully launched. On July 19, Tiangong-2 docked automatically, which took 2 days. On April 23rd, 20021,the American-launched Dragon Spacecraft Endeavour successfully docked with the International Space Station in 24 hours. Shenzhou 12 adopts 6-hour fast docking mode, which is much faster than most express delivery on earth. Why can it be so fast?

Is the 6-hour fast docking mode the fastest?

Although China's space docking has entered the era of 6-hour docking, it is not the fastest. The Russian spacecraft MS- 18, launched on April 9, 2002/KLOC-0, has achieved an ultra-fast docking mode of 3 hours and 2 minutes, which is the fastest docking with the space station in history.

Soyuz spacecraft docking

The fastest docking record in space history

The 3-hour ultrafast mode of Russian Soyuz is the shortest time to dock with the space station, but it is still not the fastest space rendezvous and docking in the world.

1967 10 10 On October 30th, two Russian unmanned spacecraft 186 and 188 realized the super-fast docking (spacecraft docking) of 1 hour for 8 minutes, which was the first time in human history that the spacecraft automatically docked, and the time was recorded.

Russian rocket launch

1March, 966 16, American astronauts Armstrong and Scott docked with the unmanned aerial vehicle "Aquinas" on Gemini 8 spacecraft manually, which was the first docking of the human space station. In addition, the American Gemini manned spacecraft set a docking record of 1 hour for 34 minutes.

How did the spacecraft dock with the space station?

When launching a spacecraft to dock with the space station, first of all, the spacecraft needs to be on the same plane with the space station when launching. This is generally achieved by the rotation of the earth, so this launch has a time window.

Two problems to be solved in the docking of spacecraft and space station

After the spacecraft is launched into orbit, it will begin to orbit the earth in a lower orbit. In order to catch up with the space station in a higher orbit, it is necessary to solve two problems: height difference and phase difference (angle difference). Generally speaking, there are two methods:

The first is the stable orbit tracking method, in which the spacecraft first solves the height difference problem and reaches the same orbit height as the space station after two accelerations. Then, after several deceleration, the phase difference is shortened by using the method of short orbital period, so as to catch up with the space station.

Stable orbit tracking method 1

Stable orbit tracking method II

The second is the same elliptical orbit method, which first adjusts the angle, then adjusts the height, and then approaches the orbit of the space station after several orbital changes. When the two orbits are very close, they will slowly change their orbits from below and behind the space station. This method takes a long time, usually 2~3 days, but it is relatively stable.

Homoelliptic orbit method

One of the reasons for Russia's ultra-fast docking is that the International Space Station starts to launch when it passes the launch point, when the phase angle difference is the smallest. Secondly, we don't do any unnecessary flight during the flight, and we start to change orbit without completing a circle during the orbit operation of the spacecraft, so that we can catch up with the space station in less than two circles around the earth.

Of course, Russia's ultra-fast docking principle seems simple, but it requires not only profound technical accumulation, but also rich practical experience to calculate various errors such as orbit calculation, spacecraft positioning and acceleration increment very accurately.

Orbit change signal

Which countries have mastered the sky docking technology?

So far, there have been more than 500 space docking in the world, most of which were carried out by the United States and Russia. Although more than 50 years have passed since the first docking, only the United States, Russian Federation, China, ESA and Japan have independently mastered the space docking technology.

Significance of six-hour docking of Shenzhou-12 spacecraft

Shenzhou 12 docking interface

China Shenzhou-12 spacecraft adopts 6-hour fast docking mode, which shows China's profound accumulation in space technology and can carry out high-precision and technically difficult space activities. It also shows that China has changed from a space power to a space power. The Tianzhou-2 cargo spacecraft launched on May 29th, 20021year also adopted the fast docking mode of 6 hours (actually 8 hours), which can be said to be a drill for the manned spacecraft in advance.

It takes only 6.5 hours for Shenzhou-12 and Tianhe core cabin to rendezvous and dock independently. Have you noticed that both Shenzhou/KOOC-0/and Shenzhou/KOOC-0/2 were launched by the Long March II F rocket, and the Long March II F almost became the special "mount" for China astronauts, with a success rate of/KOOC-0/00%, then we will.

The Long March II F rocket has a total length of 58.34 meters, consisting of first and second stages, a diameter of 3.35 meters, a booster diameter of 2.25 meters, a fairing diameter of 3.8 meters and a takeoff mass of 479.8 tons. It can send 8.4 tons of payload into low earth orbit at a time. The Long March II F propellant uses nitrogen tetroxide and unsymmetrical dimethylhydrazine, and its takeoff thrust is 604.387 tons.

Most importantly, the reliability and safety of Long March II F are 0.97 and 0.997 respectively, which is the highest among all types of rockets in China, which is why China wants to use it as a special "mount" for astronauts in shenzhou spaceship and China.

Long March II was launched 15 times, * * 17 people traveled in space, Shenzhou 5 Yang Liwei, Shenzhou VI Fei and Nie Haisheng, Shenzhou VII Zhai Zhigang, Jing Haipeng and Liu Boming, Shenzhou IX Jing Haipeng, Liu Wang and Liu Yang, Shenzhou X Nie Haisheng, Zhang and Wang Yaping, Shenzhou Jing Haipeng and Shenzhou XII Nie Haisheng.

Shenzhou 12 spacecraft is carrying three China astronauts to China Space Station step by step, and will rendezvous and dock with China Space Station in a few hours. By then, China people will become the first occupants of the China Space Station, and we have finally realized the long-awaited "Space Station Dream".

As we all know, the International Space Station built by the United States and Russia has been running for more than 20 years, that is to say, it has the word "international" in its name, but it is actually very incompetent. The United States has been preventing China people from entering.

But now, it is not China that envies the United States, but the United States envies us, because the International Space Station is aging and will be retired around 2025, while the China Space Station has just begun.