On September 15, 2023, with the theme of "Towards High-level Scientific and Technological Self-reliance and Self-reliance", the Science Popularization China Starry Sky Forum invited five experts from the fields of superconducting technology, marine resources, aerospace science and technology, meteorological forecasting, water conservancy and hydropower, focusing on China's five most representative sciences and technologies that effectively benefit the people, focusing on "what is 'strong' in a rich and powerful country", leading the public to feel the spirit and charm behind mainland science and technology and scientific research work.
Professor Zhang Wei, Director of the Application Development Center of the Space Application Engineering and Technology Center of the Chinese Academy of Sciences, delivered a speech: A firm step in mainland space exploration.
, duration 20:14
The following is an excerpt from Zhang Wei's speech:
Since the establishment of the manned space project in 1992, the mainland has determined the "three-step" development strategy.
Development of the continental manned spaceflight project, photo courtesy of the speaker
The first step is to launch a manned spacecraft and carry out space application experiments.
The second step is to break through the launch space laboratory and solve the problem of space applications with a certain scale and short-term manned care.
The third step is to build inter-station stations to solve the problem of large-scale, long-term manned space applications.
At the end of 2022, the space station was fully completed, which is a firm step in continental space exploration, and it has built a national space laboratory, entering a 10-year or even 20-year stage of space application and development.
Although our space station is later than the International Space Station led by 16 countries such as the United States and Russia, our space station has achieved two-thirds of the number of scientific experiment cabinets and the same discipline support capacity with the scale of one-quarter of the International Space Station, and the resource utilization rate is very high, and the mainland space station is built by the continent self-reliant and independent, and the system is very complete, fully reflecting the progress of mainland manned space technology and development.
"Space-earth integration" system architecture
In order to achieve a strong support for so many tasks, we propose a "space-earth integration" system architecture, including centralized shelf distribution, which also involves this open and flexible architecture.
Sky: The system includes more than a dozen science experiment cabinets, space survey telescopes, and a high-speed optical fiber backbone network to interconnect them.
Ground: There are mission development support systems, payload transport systems, and scientific application centers distributed throughout the country, thus forming a space-ground collaborative scientific research and support system.
Our space station scientists can directly operate the experiments on the space station in real time through our space-earth interconnection circuit in the pre-control center. The planning of more than 10 scientific experiment cabinets covering life, fluids, combustion, materials, basic physics and other disciplines was accurate at the time of planning, and the indicators were very advanced.
"Tiangong" space station, photo courtesy of the speaker
Including two system experiment cabinets, high-risk power experiment cabinets, both of which are proposed for the first time in mainland China to meet the needs of international cutting-edge scientific research on the space station.
The survey space telescope will also fly in common orbit with the space station, and if necessary, it can be docked to the space station, and astronauts will repair and maintain it, and can also update and replace modules.
Space Survey Telescope, photo courtesy of the speaker
It has a 2-meter aperture, has 5 back-end modules, has a resolution comparable to Hubble, and has a field of view 300 times larger than Hubble, and it surveys 42% of the entire sky region through a 10-year period.
This indicator is very high, compared with the same project of the entire international space, it has the highest angular resolution, the largest field of view, the widest band coverage, and is the highest level of space facilities.
At present, our space station has been completed and has entered a long-term application and development stage.
Complex solutions for large systems
Our space station proposes a complex large system solution of "space-earth collaboration, software-driven, digital twin, dynamic openness", and establishes a digital twin system for space applications, which can realize the parallel dual processes of physical development and digital development, and constantly optimize and iterate.
Efficient load development and operation, at the same time through the high-speed optical fiber backbone network, the establishment of stable and reliable operation of high-level application in orbit shared support conditions, and breakthrough scientific experiment cabinet, lightweight structured, highly integrated a core technology, is a number of international advanced space experiment facilities.
Take containerless material experiment cabinets and ultra-cold atomic physics experiment cabinets as examples to tell our story.
Containerless experiment cabinet
This project was established at the latest, but the earliest in heaven.
The containerless material experiment cabinet is to suspend the material sample in the air and process it through laser heating to prepare the required materials.
At the beginning of the project, it was determined that beyond the International Space Station, the technical indicators of Japan and Europe, including the materials, support types and thermophysical side materials, are the highest level in the world.
Space science experiment facility cluster, photo courtesy of the speaker
In order to achieve this goal, many difficulties have been overcome, and within 3 years, the containerless experimental cabinet has experienced the development of 5 generations of products, and has been iterated at a very fast development speed, the scheme is to be continuously optimized, the indicators are constantly improving, and the high quality is launched as planned.
After the sample is suspended, because it is heated with the change of temperature, its charge will flip, and the charge will change, so it will often fall, and even the particles will run away, so the sample in orbit is suspended, this control is very difficult, and the ground to operate it, but also need to give it some parameters, it is also very difficult.
In order to solve the problem, we developed a digital twin system, reproduce the state of a device in the sky, implement simulation, simulation, timely judgment of the state of the equipment in the sky, judge the problem, and greatly improve the efficiency of equipment debugging.
When debugging the containerless experiment cabinet, the International Space Station took two years, and we only used three months, and the current containerless experiment cabinet is running stably in the sky, and now hundreds of samples have been successfully carried out experiments, and a series of results have been produced.
Ultra-cold atomic physics experiment cabinet
The lower the temperature of the substance, the stronger the dipole action of the atoms, and the more new physical mechanisms can be discovered.
To this end, Peking University and scientists from the Shanghai Institute of Optics and Mechanics, Chinese Academy of Sciences jointly proposed an innovative scheme of two-stage magneto-optical trap plus two-stage evaporative cooling, which is further than the world, so the development is very difficult, you can take a look, to do the ground volume of 20 cubic meters, weight of 10 tons of an ultra-cold atomic physics experimental system to concentrate and concentrate and then concentrate, to carry out a large number of miniaturized development, Concentrated into a 1.5 cubic meter, 500 kg scientific experiment cabinet, it can be said that this difficulty is very large, the most critical stage of development is the integrated debugging experiment stage, which happens to be the most severe time of the epidemic.
Ultra-cold atomic experiment cabinet BEC, photo courtesy of the speaker
In order to ensure the smooth progress of the research and development task, the Shanghai Institute of Optics and Mechanics, Chinese Academy of Sciences, established the Shangguang Sharp Knife Company, 68 party members and backbones chose to "retrograde" in the epidemic, closed in the institute, stuck to the front line of tackling problems, and worked in the institute for 3 months, day and night are no different for him, sleepy to lie in bed for a while, and then wake up and continue to work, it is this spirit that ensures the timely delivery of the scientific experiment system.
Including Chen Weibiao, director of the Shangguang Institute, who stuck to the unit during the epidemic lockdown, slept on the marching bed every day, and commanded at the front line, which can be said to have given great encouragement to the members. Therefore, the development process of the ultra-cold atomic experiment cabinet with a sharp knife is the best interpretation of a manned spaceflight spirit that is "particularly able to endure hardships, special ability to fight, special ability to tackle problems, and special ability to dedicate".
Experiments on the space station
The space station has been in orbit for more than a year, and has carried out nearly 100 experimental studies in space life science, fluid science, material science, etc., and its results are emerging bit by bit, trickling down and will converge into rivers and seas.
Plant incubator for the space station
Plant incubators, capable of long-term cultivation of plants, are now the first in the sky to achieve a full life cycle of rice from seed to seed. Then, we have discovered some important genes that regulate flowering and aging, and through this we hope to modify rice plant type and seed quality at the molecular level, and promote the cultivation of new varieties of rice on the ground and in space.
Growth of embryonic stem cells under spatial microgravity conditions
Photo courtesy of the speaker
In the follow-up in plants, it is hoped that molecular, cellular, whole and parent-child inheritance will conduct multi-level plant research, study the perception and response of plants to gravity, understand how gravity affects plant growth, development and metabolism, and hope to use modern gene regulation methods to carry out radiation mutagenesis breeding, hoping to make some new discoveries and applications in seed industry, agriculture, forestry and other aspects.
Cell research
Bone cells, muscle cells, stem cells... A variety of cells were cultured and studied in space, and some initial results were achieved.
Spatial cell research planning, photo courtesy of speaker
For example, using human embryonic stem cells, primitive germ cells are cultured in vitro, further revealing how the differentiation process of human embryonic stem cells and microgravity affect it, what needs to be done next, to do life in space, and hope to give birth to the first mouse in space, which is certainly the first in the world.
In addition, the culture and osteogenic differentiation of human mesenchymal stem cells have been successfully realized, hoping to explore the causes of osteoporosis caused by microgravity. The research of space cells is also long-term, including plants and animals, focusing on the function of cells under space conditions, the study of biochemical molecules, especially to carry out in-depth stem cell research, to develop the means of regenerative medicine, to provide new means and new ideas for the regeneration of ground tissues and organs.
materials science
Two scientific experimental facilities, carrying out the research and analysis of metal alloys, amorphous materials and other materials, for the first time obtained shell/core structure microstructure phase separation alloy composite materials, hoping to promote the development of composite conductive materials, photosensitive materials, advanced hydrogen production materials, these very special phase separation composite materials; At the same time, high-temperature refractory alloys were found in space, which is a rapid eutectic growth dynamic mechanism of nickel-silicon alloys, laying an important foundation for the development of niobium alloy materials for the next generation of aircraft engines.
Porous material, photo courtesy of the speaker
Microgravity conditions, a variety of materials can be well combined, so it can prepare uniform structure, few defects, strong function of advanced materials, the future hope to be able to carry out high-performance alloy materials, such as aircraft engine single crystal blades, functional crystals, biomedical materials, these are important in Beijing's material research, hope to solve the national "stuck neck" problem to make a unique contribution.
Of course, these results are only some of the preliminary results achieved since the operation of the space station. In the application and development stage of the space station, thousands of scientific research projects will be collected on a rolling basis for implementation in orbit, which will promote the comprehensive development of space science, space technology and space applications.
Space science aspects
Major scientific discoveries have been made in dark matter detection, space life breeding, and quantum new state of matter.
In addition, in the benchmark of space-based space-time, we have high-precision cold atomic clocks, optical communication and autonomous navigation in Earth-moon space, space intelligent manufacturing and construction, these key core technologies have made breakthroughs, and hope to promote the progress of stem cells and regenerative medicine, advanced material research and development, ultra-low pollution combustion, ultra-precision sensors in these aspects of application, hoping to serve the development of the national economy and people's life and health.
At present, the mainland manned lunar landing mission has been fully launched. After key technical research and in-depth demonstration of the scheme in previous years, the mainland manned lunar landing mission has a good foundation and has entered the implementation stage of the lunar landing.
It is expected that around 2025, the mainland will achieve manned circumlunar flights; Chinese landing on the moon by 2030; After 2030, it is hoped that a lunar scientific research station can be built, systematic lunar exploration can be carried out, and lunar resources will be explored, developed and utilized.