Why can Russia join the International Space Station but China cannot?

China’s manned space program

According to China’s aerospace industry development plan, the manned space program is implemented in three steps. The first stage is to launch unmanned and manned spacecraft to transport astronauts. Safely send the astronauts into low-Earth orbit, conduct earth observations and scientific experiments, and return astronauts to the ground safely.

The successful launch and return of "Shenzhou VI" marks the successful completion of the first phase. The second stage is to continue to break through the basic technologies of manned spaceflight: multi-person multi-day flights, astronauts leaving the cabin to walk in space, and completing the rendezvous and docking of the spacecraft and the space capsule. On the basis of breakthroughs in these technologies, short-term manned space laboratories will be launched and a complete supporting space engineering system will be built. The third stage is to establish a permanent space laboratory and build China's space engineering system. Astronauts and scientists can travel between the earth and the space station to conduct relatively large-scale space science experiments.

Short-term manned space station plan

It is understood that the "Shenzhou VII" to be launched this year, as the first experiment of the second phase, will enable astronauts to travel outside the vehicle. . The subsequent "Shenzhou VIII" and "Shenzhou IX" spacecraft will no longer carry humans, and are designed to launch target aircraft and achieve unmanned docking. The subsequent "Shenzhou 10" will once again carry people to space and realize manned docking. These spacecrafts are used to build short-term manned space stations in space.

The general appearance of China's space station

Regarding the space station that our country will eventually build, Qi Faren, an academician of the Chinese Academy of Engineering and the former chief designer of the "Shenzhou" spacecraft, described the general appearance of the space station: It includes A core module, a cargo spacecraft, a manned spacecraft and two other modules used for experiments and other functions, with a total weight of less than 100 tons. The core module needs to be manned for a long time and can be docked with various experimental modules, manned spacecraft and cargo spacecraft. However, only rockets with a carrying capacity of more than 20 tons are qualified to launch the core capsule. In addition, during the operation of the space station, a cargo spacecraft with a large carrying capacity is also required to transport a large amount of materials back and forth. At present, our country's rocket carrying capacity is only 10 tons. The Long March 5, a high-thrust launch vehicle being developed by China, will have a carrying capacity of more than 20 tons.

Ye Xun, director of the Manned Space Administration Department of the Shanghai Space Administration, pointed out that my country’s manned spaceflight still faces many challenges, and many technical bottlenecks need to be broken through, such as in-cabin regenerative environmental control technology and life support technology, and space station on-orbit technology. Flight technology, etc. (August 15, 2008) Source: Shanghai Government Network

Related News

According to People's Daily News on the 9th, the "Shenzhou VIII" will launch an unmanned target aircraft after the "Shenzhou VIII" , to prepare for my country’s space station docking. Qi Chuntang, deputy commander-in-chief of the "Chang 2 F" rocket, revealed in response to reporters' questions that the "Shenba" will be launched using an improved version of the "Chang 2 F" rocket - the "Long March 2" F/G rocket, which is expected to be launched in 2010. First flight left and right. Source: Chongqing Morning News

Related news: Shenzhou 8 to 10 are expected to be launched continuously, and Shenzhou 10 will realize manned docking

The launch interval is measured in months. Ten brings people into the "station"

A 25-ton carrier rocket can be manufactured in 6 and a half years, and the launch intervals of "Shenzhou VIII", "Shenzhou IX" and "Shenzhou X" are shortened

Southern Network News "Once the country establishes a project to develop high-thrust rockets, we can complete the manufacturing within six and a half years and conduct the first test launch, increasing the rocket's carrying capacity from the current 9.5 tons to 25 tons." Yesterday (2nd), in "Beijing" At the "Youth Aerospace Forum of the Astronautical Society", the reporter had an exclusive interview with Liu Zhusheng, chief designer of the Changzheng 2F rocket of the China Institute of Launch Vehicle Technology. He revealed the progress of my country's new generation of large launch vehicles and plans for the "Shenzhou" series of spacecraft.

Revealing the secret of the rocket "Hercules"

The 25-ton transport capacity can "carry" the space station

The 25-ton high-thrust launch vehicle is basically equivalent to the top level in the world. It can launch space stations in low orbits and serve lunar exploration and other deep space explorations in high orbits.

The rocket "Hercules" is needed to land on the moon

Reporter: Where will the new generation of large rockets be used?

Liu Zhusheng, chief designer of the Changzheng 2F rocket of the China Institute of Launch Vehicle Technology (hereinafter referred to as Liu Zhusheng): my country’s space program also has plans to launch a space laboratory after manned spaceflight.

When launching the space laboratory, the existing Long March 2F launch vehicle used for the Shenzhou VI could not adapt to the high thrust requirements, so a new generation of large launch vehicles must be developed. In addition, our country's lunar exploration plan is divided into three stages: "orbiting, landing and returning". Since the latter two stages require landing on the moon and back, they also require a lot of energy as support. The 25-ton launch vehicle can launch space stations in low orbits and can also serve lunar exploration and other deep space explorations in high orbits.

Reporter: What kind of rocket will be used to orbit the moon?

Liu Zhusheng: A long 3A rocket will be used to launch satellites around the moon, because the first step of landing on the moon is to orbit the moon, which saves energy and does not require a rocket with too much thrust. As for the "landing" and "returning" stages, a new generation of high-thrust rockets must be used.

The new rocket uses environmentally friendly propellant

Reporter: Has the appearance of the new generation rocket been changed?

Liu Zhusheng: The appearance is not much different from the current rocket, but the diameter will be increased from 3.35 meters with a length of 2F to 5 meters, and the carrying capacity will also be increased from the current 9.5 tons to 25 tons.

Reporter: Has the propellant been changed?

Liu Zhusheng: Rockets in the past used a single engine, but the new generation of launch vehicles in the future will use dual-engine technology. The two engines use different propellants. One engine burns liquid hydrogen and liquid oxygen, and the other burns liquid oxygen and kerosene. The propellant used in today's rockets is toxic nitrogen tetroxide. The propellants used in the new generation of rockets are environmentally friendly materials - liquid hydrogen, liquid oxygen and liquid oxygen kerosene. The compounds produced by liquid hydrogen and liquid oxygen are only water, so it is a clean and environmentally friendly energy source. Liquid hydrogen and liquid oxygen propellants have long been used in our country's rockets, and the technology is also very mature; while liquid oxygen and kerosene have only been used in small engines, and such propellants are currently used abroad.

25 tons reaches the top international level

Reporter: If our country can build a 25-ton high-thrust launch vehicle, will there still be a gap with the international leading level?

Liu Zhusheng: If it reaches 25 tons, it will basically be equivalent to the top international level. In fact, let alone 25 tons, it can also be achieved even higher. However, rockets with greater thrust will not be developed for a period of time, because the development of rockets is to meet the development of satellites and spacecrafts, and satellites cannot "grow" endlessly. However, if you do not develop high-thrust rockets, you will not be able to hit slightly larger satellites, which is equivalent to automatically withdrawing from this launch market.

Reporter: Does the new generation of large rockets have new requirements for aerospace materials?

Liu Zhusheng: Yes, for example, liquid hydrogen, liquid oxygen and liquid oxygen kerosene must be installed in low-temperature storage tanks. The low-temperature storage tanks need to be insulated, but they cannot be made very thick. Now there is a solution to use composite materials, with carbon fiber on the outside and a very thin metal layer on the inside. Now small ones can be made, but there are still many problems that need to be solved to make a 5-meter-diameter storage tank.

Foreign commercial satellites can be launched

Reporter: Is it difficult to develop a new generation of large rocket technology?

Liu Zhusheng: Now the scheme design has basically been completed, and there are no technical problems. We will wait for the national project to be approved before conducting preliminary design and large-scale ground experiments. At present, the image measurement function still needs to be improved. The main function of image measurement at this stage is to take images of rocket separation. In the next step, the new generation of large launch vehicles will increase the scope of use. In addition to monitoring rocket separation images, it also monitors some temperatures. Field measurement.

Reporter: When is the specific time for the project to be approved?

Liu Zhusheng: The specific time is not known yet, but it is listed in the "Eleventh Five-Year Plan".

Reporter: Are high-thrust rockets preparing to launch foreign satellites?

Liu Zhusheng: Of course we can provide launch services for foreign commercial satellites. In fact, all rockets can now provide launch services. In the past, our rockets were relatively powerful and the lifespan of satellites could not reach that high, so we could only launch other people's satellites. Now we plan to adopt a bundling method. You buy my satellites, and I will use my rockets to launch them for you.

Revealing the secrets of the Shenzhou series

The "Three Brothers" of Shenzhou are released once a month

Starting from the "Shenzhou Eight", the "Shenzhou Nine" and "Shenzhou Ten" are all Soon, more than a month is considered a long time. Once a target is up, the next one needs to be launched immediately for docking, so it will be launched very quickly.

"Shenzhou VIII" and "Shenzhou 9": They only explore the path but do not carry people

Reporter: Will "Shenzhou VII" use such a high-thrust rocket to send people up? How many astronauts will there be on "Shenzhou VII"?

Liu Zhusheng: According to the current plan, the Shenzhou VII will be launched in two years' time, and it will not require a high-thrust launch vehicle. The Long March 2F rocket will still be used. "Shenzhou VII" is planned to have three people, because when someone goes out of the cabin for activities, three people must work together to complete it.

Reporter: Are there any manned plans for the future "Shenzhou VIII" and "Shenzhou IX"?

Liu Zhusheng: Since the "Shenba", unmanned target aircraft have been launched, that is, space laboratories. They do not carry astronauts, but are only sent to the sky to complete the docking of the laboratory. "Shenba" is a small space laboratory with many interfaces. Including "Shenba", the current space laboratories are all prepared for the future space station. We need to examine how people will work and live for a long time after going up there. Whether it will work or not, and what problems will be encountered on it, all need to be explored, because there are many problems that you can't even think of happening.

"Shenzhou 9" does not have astronauts, it only launches target aircraft.

"God 10": Astronauts are going to enter the space laboratory

Reporter: When will the manned program be restarted?

Liu Zhusheng: In fact, "Shenzhou VIII" and "Shenzhou IX" both went up to explore the way to see whether the docking technology was mature. It was not until "Shenzhou X" that astronauts were brought up again to carry out space laboratory work. .

The "Three Brothers" launches are one month apart

Reporter: Do the launch intervals of "Shenzhou VIII", "Shenzhou 9" and "Shenzhou 10" also need two years?

Liu Zhusheng: It won’t be that long! Starting from the "Shenzhou VIII", the "Shenzhou 9" and "Shenzhou 10" are very fast, more than a month is considered a long time, because when one target goes up, the next one needs to be launched immediately for docking, so it will be launched very quickly. . (Note: around 2010)

Latest progress

It took six and a half years to build the rocket "Hercules"

"Once the country establishes a project to develop high-thrust rockets, we It can be manufactured within six and a half years." Yesterday, President Wu Yansheng of the China Academy of Launch Vehicle Technology revealed the research status of my country's high-thrust launch vehicle. He said that this will increase the maximum carrying capacity of our country's launch vehicle from the current 9.5 tons to 25 tons.

He said that launch vehicles are the basic system for space exploration. "It can be said that how big the rocket's carrying capacity is, how big the stage for space exploration is."

At present, my country's rocket with the largest carrying capacity is the Long March 2F, which has undertaken the "Shenzhou VI" launch mission. Its low-Earth orbit carrying capacity has reached 9.5 tons, while the world's largest launch vehicle has a low-Earth carrying capacity of 25 tons.

"In terms of high-thrust launch vehicles, there is a 6-year gap between our country and the world's most advanced level." Wu Yansheng said that currently, our country has made breakthroughs in key technologies of high-thrust launch vehicles and has entered the In the model research stage, the first test launch can be completed within 6 and a half years after the national project is approved. This also means that the gap between my country's high-thrust launch vehicles and the world's level is narrowing.

He also revealed that the overall scientific research funding for the project requires approximately one billion yuan.

Two key technologies need breakthroughs

Yang Hong, deputy chief designer of Shenzhou 6 of China Academy of Space Technology, introduced in his keynote speech that in 2004, the central government approved manned spaceflight The second phase has been officially launched. Currently, our country is undergoing the second phase of the second phase of the manned spaceflight project.

This project will focus on breakthroughs in two major technologies. The first is to complete the astronauts’ exit from the cabin and conduct space walks, for which extravehicular space suits must be designed to adapt to extravehicular activities. The second technology is to complete two Spaceships interact and dock in space, and astronauts' extravehicular walking was the plan for the "Shenzhou VII".

Yang Hong said that after the completion of these two technologies, short-term manned space laboratories will be further established, and then permanent space stations will be established