(China Focus Face to Face) How "God" is "God Twelve"? Do ordinary people have a chance to go to the space station?
China News Service, Beijing, September 17th, title: How "God" is "God Twelve"?
Do ordinary people have a chance to go to the space station?
——Interview with Yang Yuguang, vice chairman of the International Astronautical Federation Space Transportation Committee and researcher of the Second Academy of China Aerospace Science and Industry Corporation
Author Ma Shuaisha Guo Chaokai
On September 17, the three astronauts Nie Haisheng, Liu Boming, and Tang Hongbo took the Shenzhou 12 spacecraft return capsule to return to Earth and successfully landed on the Dongfeng landing site.
During the three-month "space business trip", how did the astronauts guarantee their food, clothing, shelter and transportation?
How will the Chinese space station be built in the future?
Do ordinary people have the opportunity to go to the space station?
Yang Yuguang, vice chairman of the International Astronautical Federation Space Transportation Committee and a researcher of the Second Academy of China Aerospace Science and Industry Corporation, accepted an exclusive interview with China News Agency "China Focus Face-to-face" and gave an authoritative interpretation.
Excerpts from the interview are as follows:
Reporter from China News Service: During the three-month period of "space business", the Shenzhou 12 flight crew arranged two missions out of the cabin. What are the differences between the two missions and what missions are arranged for each? Compared with Shenzhou VII’s mission, Shenzhou 12’s mission took longer. Does this mean that China’s technology for extravehicular activities has been greatly improved?
Yang Yuguang:
Building a space station is a very complex project with many key technologies, such as the three basic technologies for manned spaceflight: space-to-earth shuttle technology, rendezvous and docking technology, and extravehicular activity technology.
In 2008, Shenzhou VII took less than 20 minutes to leave the cabin, and the extravehicular activities were relatively simple. It just proved that we have the ability to carry out extravehicular activities, but it cannot meet the needs of complex scientific research activities in the future.
The Shenzhou 12 crew carried out two extravehicular activities to further verify the technology of extravehicular activities.
First of all, this time the three crew members are wearing China's second-generation flying space suit, which has a longer working time. In theory, it can work for eight or nine hours and can be reused 15 times.
Video screenshot
The two outings of the Shenzhou 12 mission were more about technical verification, especially the first extravehicular activity that lasted more than 7 hours. The second-generation flying spacesuits required various technologies to support long-term extravehicular activities. Fully verified.
The first extravehicular activity also verified two key technologies. One is to use a robotic arm to assist astronauts in large-scale transfers on the surface of the space station, and the other is to crawl on the surface of the space station and climb to a designated location through safety ropes and fixtures. .
The task of the second extravehicular activity was more complicated. An extended pump set was installed to improve the working reliability of the entire space station.
Data map: After entering the space station, the three astronauts reported to the people of the country and paid their respects.
(Video screenshot) Image source: Visual China
China News Service: The average age of the Shenzhou 12 flight crew is over 52 years old. Some netizens said that the astronauts on this mission are too old. Why not choose younger astronauts? Are there any restrictions on the age of astronauts in manned spaceflight? Will China need to further strengthen the echelon of astronauts in the future?
Yang Yuguang:
More than 50 years old is not a very big age. The United States, Russia and other countries have a large number of astronauts over 50 years old.
The highest age record is John Glenn, the first American astronaut to make an orbital flight. He piloted the Mercury spacecraft in the 1960s for the first U.S. space flight around the earth. He was close to 80 years old. Elderly took the space shuttle to enter space again.
It takes at least two years for astronauts to be qualified for actual flight from the initial selection to the long-term physical adaptability and various space operation skills training.
In the past, when conducting important space missions abroad, at least one person (in the crew of astronauts) had space flight experience.
For example, in the crew of the Apollo 11 spacecraft that landed on the moon for the first time in the United States, all three astronauts had experience in space flight before.
The mission of Shenzhou 12 is very important. It has undertaken tasks such as the first long-term stay, renewable environmental control and life support system, and complex exit activities. It also requires an experienced crew.
From the beginning of the Shenzhou 9 mission, it was generally "one old with two new" or "one old with one new". This time it became "two olds with one new". Even Nie Haisheng had two flight experiences in the past.
Data map: On July 30, 2021, astronaut Tang Hongbo photographed thousands of lights on the North African continent.
Photograph by astronaut Tang Hongbo Image source: Manned Space Office
China has now completed the selection of the third batch of astronauts, including not only space pilots, but also space mission experts and onboard engineers.
The first generation of astronauts were all selected from pilots. In the third batch of astronauts, because the proportion of space station mission scientific research is getting higher and higher, more engineers and scientists need to enter orbit to conduct more complex space science. Research and practical operation.
China News Agency reporter: The Shenzhou 12 flight crew has been in orbit for as long as 3 months. In the future, the astronauts’ stay in orbit on the Chinese space station will increase to 6 months. What is the significance of developing space technology and conducting space experiments?
Yang Yuguang:
Long-term stay has to solve many problems, such as muscle atrophy and bone calcium loss under conditions of weightlessness.
The "Tianhe" core module is equipped with a space treadmill and a space bike, which is more reasonable than the previous design and can be used for more effective exercise.
Another problem that must be solved for long-term space stay is the renewable environmental control and life support system, and many resources have to be recycled.
Take urine processing as an example. In fact, the urine is sent to the vapor compression distillation device. First, let it become a very low pressure, which is easier to evaporate and vaporize. After vaporization, the water vapor is separated, and the water vapor is condensed to form distilled water. , After some treatment, and then filtered through the purification system, it can reach the standard of drinking water.
Yang Yuguang, vice chairman of the International Astronautical Federation Space Transportation Committee and researcher of the Second Academy of China Aerospace Science and Industry Corporation.
Photo by China News Agency reporter Jiang Qiming
Astronauts usually draw blood regularly, and the blood samples must be brought back to Earth for study.
In the future, astronauts will be in orbit for more than half a year from Shenzhou 13 onwards.
The various problems discovered this time can lay a very good foundation for the future stay in orbit.
In addition to supporting scientific research activities, on-orbit flight also lays the foundation for further deep space in the future.
For example, it takes more than a year and a half for an expedition from Earth to Mars, and most of the time is spent in a spacecraft. Such a process must first be verified in a low-Earth orbit space station.
China News Agency reporter: After the three-month "space business trip", the Shenzhou 12 flight crew returned to Earth smoothly and returned from the microgravity environment of space. What preparations should the astronauts do in advance to adapt to the Earth environment faster?
Yang Yuguang:
Judging from the announced plans for the life and work of the astronauts in orbit, we have noticed a detail. They will increase their daily exercise time and intensity when they return. This is a very good preparation.
In order to ensure that bone calcium is not lost and muscles are not atrophy, astronauts must exercise enough every day to adapt to gravity as soon as possible after returning to Earth.
This flight is also the longest (currently) Shenzhou spacecraft has been in orbit.
After the Shenzhou spacecraft berths to the space station, although most of its equipment is in a dormant state, it will still experience the test of the space radiation environment and the harsh vacuum environment.
Shots taken by Shenzhou 12.
Photo by astronaut Liu Boming
The Shenzhou spacecraft is related to the safety of the astronaut crew, so before returning, it is necessary to test the various sub-systems such as the propulsion system, the GNC sub-system (guidance, navigation and control sub-system), and the measurement and control sub-systems to ensure that each sub-system is Only normal ones can return.
This is the first time we have returned to the Dongfeng Landing Site. In the past, all (manned) spaceflights were returned to the Siziwangqi Landing Site. The Dongfeng Landing Site was used as a backup landing site.
In the future, the Dongfeng Landing Field will be used as the main landing field during the operation phase of the space station.
China News Agency reporter: What are the main considerations for the changes in the landing site?
Yang Yuguang:
Most of the manned spacecraft, including the space station, are at relatively low orbital altitudes, mainly to avoid the effects of space radiation.
Because there is a Van Allen radiation belt near the earth, the lower edge of this radiation belt is about 600 to 700 kilometers high. If the orbital altitude of the spacecraft is higher than this altitude, it will be affected by more radiation. Height, radiation will be much smaller.
But this brings another problem, because this altitude orbits the earth at 7.8 kilometers per second, and the atmospheric drag received will cause the altitude of the spacecraft or space station to continue to decrease.
In the past, the crew missions of Tiangong No. 1, No. 2 and Shenzhou spacecraft did not require large-scale orbit changes because the time was relatively short. The space station was in orbit for a long time, and the height of the orbit changed greatly. When appropriate, an orbit maintenance was required. Raise the height.
The larger change in orbital height brings about a problem. Theoretically, the position of the landing site will have a larger change when returning.
The Siziwangqi landing site is a relatively small landing site, while the Dongfeng landing site is located near the Jiuquan Satellite Launch Center. It has a very large area and can have a long range for selection.
I think this may be the main reason for choosing the Dongfeng Landing Field as the main landing field during the operation phase of the space station.
China News Agency reporter: How to ensure the safety of astronauts during the return to Earth?
Yang Yuguang: The
return process is the same as the launch process. It is a relatively risky part of space flight.
At present, there have been some dangerous accidents during human flight in orbit, most of which occurred during the launch phase and the return phase.
There are several risks in the return process.
The first is reverse thrust. It was originally an orbit around the earth. Through the work of the propulsion cabin engine, it can be changed to a reentry orbit. This is a relatively risky link. First of all, it must be accurate.
The second is that there are several separation operations during the return process. The first operation is the separation of the orbital module from the entire spacecraft, which we call the orbital return separation; the second is that after the reverse thrust is completed, the propulsion module and the return module should be separated, which we call This is push-back separation. Both separations are very important and must be completed normally.
During the reentry flight, that is, below 100 kilometers, the return cabin and atmospheric friction will generate extremely high temperatures.
There is a heat-resistant outsole under the spacecraft, and the surface of the spacecraft has heat-resistant ablation materials to ensure that high temperatures will not be transmitted to the cabin and ensure the safety of the astronauts.
When returning to a height of about 10 kilometers and the speed has dropped to more than 200 meters (per second), the parachute must be opened to further reduce the speed.
In order to ensure the safety of astronauts, there is a set of main parachute and a set of backup parachute. Once the main parachute is opened and there is a problem, the backup parachute must work to ensure that it can descend to a relatively low speed and land normally on the surface of the earth. The impact of the staff is still relatively large.
So we have two more measures. One measure is to raise the seat before landing, which is a bit like an air pressure rod for a folding bed at home; the other measure is to throw off the heat-proof outsole in the return cabin and reach a height of one meter from the ground. The command was issued precisely at the time, allowing several small solid rocket motors to reverse thrust, further reducing the landing speed of the spacecraft, and allowing the astronauts to land very gently on the surface of the earth.
China News Agency reporter: The three astronauts on Shenzhou 12 are all men. Will there be female astronauts in the astronaut flight crew of the space station in the future? What are the implications for the development of China’s space technology and the operation of China’s space station? Woolen cloth?
Yang Yuguang:
The importance of female astronauts is irreplaceable.
Humans enter space to conduct more scientific experiments and to go deeper into space.
From this perspective, only male astronauts are incomplete, and women have special advantages, and they have more advantages in some more detailed operations, including language advantages.
From the perspective of long-term space life, the psychological compensatory role of male and female complementarity is also very important for long-term space flight.
Judging from foreign examples, there are a large number of female astronauts not only able to stay in the space station for a long time, but some even serve as spacecraft pilots and even the commander of the entire flight mission. This situation exists.
Liu Yang and Wang Yaping have already experienced space flight as crews of China's Shenzhou 9 and Shenzhou 10 spacecraft. The time is not short, reaching more than ten days. We look forward to the emergence of female astronauts on the Chinese space station in the future. certain.
China News Agency reporter: After the trio of "Space Business Travel" triumphs, China will continue to implement multiple launch missions in succession, completing the on-orbit construction of the space station in 2022. How will the Chinese space station be built in the future? What is the complete "Tiangong" space station leader? What key role will it play?
Yang Yuguang:
The initial plan of the Tiangong space station is a T-shaped configuration. There is a node cabin at the front end of the Tianhe core module. The node cabins are connected to the left and the right, each connected to an experimental module. The right is the Wentian experimental module, and the left is the Mengtian experiment. The cabin, the two experimental cabins and the core cabin are more than 20 tons in weight, which is the basic configuration of the space station.
At 9:29 pm on August 24, 2021, the sky over Beijing.
Photograph by astronaut Nie Haisheng Image source: Manned Space Agency
In addition to these three basic sections, the Tianhe core module will dock with a Tianzhou cargo spacecraft to send living materials and scientific research instruments to the astronauts, and to the space station to send propellant refills, domestic garbage, and discarded scientific instruments. It should also be put here, not only the "courier brother", but also the "storage room" and "trash can".
One or two Shenzhou spacecraft will be docked at the front end of the space station. In the short term, the space station can support six people in orbit for crew rotation.
The space station in the future also has the ability to expand, with the possibility of adding a second core module, which can be expanded to a combined size of 180 tons in the future.
It needs to be emphasized that the weight of 180 tons is less than half of the International Space Station. This is more in line with China’s positioning as a developing country but also a major aerospace power, that is, it has a moderate scale and pays more attention to efficiency to complete more scientific experiments. Contribute to the progress of human science.
In addition to the basic configuration of the space station, there will also be an independent flying optical capsule-the sky survey telescope, which can image a large range of sky and obtain massive scientific data.
It operates on the same orbit as the space station. Normally, it operates independently. When maintenance is needed, it can be docked with the space station, and the astronauts can perform maintenance operations on it.
A large HD image taken by the astronaut in orbit.
Photograph by astronaut Tang Hongbo Image source: Manned Space Agency
China News Service: Virgin Galactic and Blue Origin have recently launched suborbital space tourism. Will ordinary people have the opportunity to go to China's space station in the future? What conditions need to be met to enter the space station?
Yang Yuguang:
I believe that there is a possibility that non-professional astronauts will enter the space station in the future.
Foreign journalists, movie stars and other paid space travel passengers have all visited the International Space Station.
For ordinary people to enter space, necessary training is indispensable.
One is to be able to withstand the environment during the flight, including overweight and severe vibration during takeoff. In this regard, adaptive training is required.
When astronauts conduct space training, they need to simulate overweight training on a centrifuge to reach 8 times the weight of their body.
The second is to carry out weightless environment training, on the one hand, experience, on the other hand, to avoid serious maladjustment in the future.
In addition, rescue training is required.
Astronauts need to survive and exercise in deserts, seas, and forests.
Astronauts engaged in extravehicular activities also need to conduct corresponding training in a salted pool, also called a neutral buoyancy pool.
These trainings are theoretically open to ordinary people, but it is true that as we said, astronauts are a one-in-a-million career. Everyone works very hard, but not everyone has the opportunity to fly into the sky.
(over)