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The great progress in astronomy in the past 60 years has enabled China to achieve a large number of scientific achievements that play an important role in promoting human exploration of the mysteries of the universe.

With the continuous development of space technology, space industry has become one of the strategic commanding heights of national high-tech development. The development of space industry has provided new historical opportunities for astronomy, and astronomy has also made important contributions to serving the country's major strategic needs. In recent years, the concept innovation of communication satellite navigation system, the phased implementation of the project and the development of application fields have laid the position of astronomical technology in major national navigation projects; The successful completion of the ground application system of lunar exploration project, the development and successful application of real-time VLBI technology in lunar exploration satellite orbit determination system, the observation and research of space targets and debris, and the system construction show that astronomy plays an irreplaceable role in major national projects and application fields.

Last year, during the Shenzhou VII flight, Chinese astronauts made their first extravehicular walk. At that time, astronauts were exposed to space in extravehicular spacesuits, most afraid of being hit by space debris, otherwise the consequences would be unimaginable. Therefore, monitoring and predicting space debris has become a necessary condition for spacewalking. The space environment is easy to "change face", and the space "weather forecast" is more difficult to grasp. Wang Yi said, "Space junk is very harmful. It is more powerful than bullets, so it is necessary to monitor space junk. To this end, the National Astronomical Observatory has established a small space debris database to catalogue all space debris, which provides a safety guarantee for astronauts to choose the opportunity to walk out of the cabin. "

In addition to monitoring space debris, there are many areas where astronomy serves aviation technology. The launch and recovery conditions and orbits of rockets, satellites and spacecraft need to be designed and calculated by using celestial mechanics theory. The position in flight needs to be determined by astronomical observation; Attitude maintenance should be corrected and controlled according to the position of celestial bodies. In addition, the violent activities on the surface of the sun often throw out a large number of charged particles and strong ultraviolet rays, which seriously interfere with the earth's magnetic field and ionosphere, leading to the interruption of short-wave radio communication. Therefore, we must observe the sun carefully, monitor and predict various activities on the surface of the sun, and determine the appropriate time for space activities.

The VLBI network of China Academy of Sciences also played an important role in another important space exploration activity in China-the lunar control project. The network is a subsystem of the orbit measurement system, which consists of four telescopes in Beijing, Shanghai, Kunming and Urumqi and a data processing center in Shanghai Observatory. The resolution of the telescope formed by such a network is equivalent to a giant comprehensive telescope with a diameter of more than 3000 kilometers, and the angle measurement accuracy can reach several hundredths of an arc second or even higher.

In the Chang 'e-1 mission, the VLBI orbit measurement subsystem of Chinese Academy of Sciences officially measured Chang 'e-1 satellite from June 27th, 2007, the first day of the 24-hour phase modulation orbit segment, and completed a large number of measurement tasks such as the 24-hour and 48-hour phase modulation orbit segment, the Earth-moon transfer orbit segment and the lunar capture orbit segment. In this survey mission, the equipment of VLBI subsystem and data processing center worked normally, and the VLBI survey data were transmitted to beijing aerospace control center in time, which met the engineering requirements and made an important contribution to the precise orbit determination of Chang 'e-1 satellite.

"Although astronomy is a basic science, it can also directly serve the actual needs. With the development of astronomy in China, it will further promote China's economic and social development and better serve the production and life of the broad masses of the people. " Wang Yi said.

Try to catch up

outstanding performance

Chen Jiansheng, an academician of China Academy of Sciences and an astrophysicist, believes that astronomy has always been a symbol of a country's national strength and civilization.

China's astronomy once had a glorious past. China has the oldest and richest astronomical records of eclipses and comets in the world, exquisite ancient astronomical instruments such as armillary sphere and simple instrument, and famous astronomers such as Zhang Heng and Guo Shoujing. Ancient astronomy in China has made great contributions to the development of world astronomy and even the whole human civilization.

After the founding of New China, everything is in ruins, and Chinese astronomy circles began to catch up with the advanced world level. Especially in the 30 years of reform and opening up, China's astronomical cause has ushered in a golden age of development. 1989 "2. 16m" optical telescope was built, which filled the gap in millimeter wave and VLBI astronomy.

Entering the 2 1 century, China has made remarkable achievements in astronomy. The completion of LAMOST is a landmark event in the history of telescope manufacturing in China. Our country has mastered the advanced technology of contemporary telescope manufacturing, and made some innovations, and built a large-field spectral survey telescope with the largest aperture and the largest number of optical fibers. The first hard X-ray modulation telescope (HXMT) for space astronomical exploration was launched. The achievements of astronomical research have gradually attracted the attention of the international astronomical community. At the same time, remarkable achievements have been made in the construction of astronomical teams in China, and a number of outstanding young and middle-aged talents have emerged.

"The development of astronomy is not simply engaged in theoretical research. It must rely on advanced observation equipment and observation stations to study the composition and changes of celestial bodies. Over the past 60 years, one observatory after another has been established all over the country, and fruitful research results have been achieved. This is actually the best proof of the rapid development of astronomy in China. " Wang Yi, a researcher at the National Astronomical Observatory of Chinese Academy of Sciences, said.

Since its predecessor Nanjing Astronomical Research Institute 1958 was established, over the past 40 years, * * has developed more than 40 kinds of astronomical instruments with complete categories for astronomical observation in China, including stellar physical observation instruments, solar physical observation instruments, satellite observation instruments, astrometric observation instruments, radio astronomical observation instruments and space astronomical observation instruments.

At present, the 40m-caliber radio telescope at Fenghuangshan Station of Yunnan Observatory, together with the 50m-caliber antenna in Miyun, Beijing, constitutes the only data receiving ground station system for deep space (moon) detectors in China. At the same time, as one of the working units of VLBI, it undertakes the tasks of data reception and orbit measurement and observation in the implementation of China's lunar exploration (Chang 'e) project.

Why has China made remarkable achievements in astronomy? Wang Yi believes that this is inseparable from the country's attention and support for astronomy for many years. First of all, China's investment in astronomical research is increasing; Secondly, in recent years, China has issued a series of talent policies, attracting a large number of overseas high-level talents and cultivating an excellent astronomical talent team; Third, a good mechanism for the development of astronomy is gradually taking shape.

Aim at the world leading level and make unremitting efforts.

"Astronomy in China has a long and glorious history, but there is a big gap with the international in the development of modern astronomy." Wang Yi said, "However, since the founding of New China, especially in the past 30 years of reform and opening up, China's astronomical cause has made great progress and has reached or exceeded the international advanced level in some fields."

A series of work by astronomers in China in the field of dark matter and large-scale structure of the universe has brought the international influence of modern astronomical research in China to an unprecedented height. They found that the electronic spectrum of the universe exceeded the theoretical prediction in the high energy band, which may be the first evidence that humans discovered the annihilation of dark matter particles; Through numerical simulation and observation statistics, the formation and evolution characteristics of large-scale structures of galaxies and the universe are revealed, and the material distribution and evolution law of dark matter halos are described. The distribution of dark matter in the universe is studied by using gravitational lens effect combined with high-energy X-rays and other observation data, and the energy level and structure of matter in the galaxy cluster, the largest gravitational binding body in the universe, are revealed.

In order to catch up with the international advanced level, astronomers in China make full use of their late-comer advantages and find another way. "Keeping pace with each other is bound to lag behind, so we must give full play to our own characteristics. For example, Huairou Solar Observation Base, although its telescope aperture is not the largest in the world, is unique in technology and irreplaceable by others, and has a high reputation in the world. " Wang Yi said.

The solar multi-channel telescope in Huairou Solar Observation Base can measure the video vector magnetic field and velocity field of the sun at different levels and scales at the same time, and obtain the spectral line profile and Stokes parameter profile through spectral scanning. It is one of the most powerful and comprehensive solar telescope systems in the world, and its observation data is at the leading level in the world.

With this "sharp weapon", Huairou Solar Observation Base is at the forefront of the world in the research of solar photosphere vector magnetic field, solar chromosphere magnetic field and physical process of solar magnetic activity, and some of its research is at the leading level in the world. Together with the Great Bear Lake Observatory in the United States, they successfully observed the "sunset" of the solar magnetic field for the first time in the world, which is a pioneering research topic in the field of solar physics.

In order to detect the "first light" emitted by the first generation celestial bodies in the universe, China deployed the first optical detection array telescope in the depths of Tianshan Mountain in Xinjiang. The facility has been in operation and observation since the summer of 2006, and it is in a leading position in the international competition of similar projects.

The National Astronomical Observatory of the Chinese Academy of Sciences also cooperated with the Argentine National University of San Juan to set up a satellite laser ranging station in South America and installed a high-precision satellite laser ranging system with a telescope aperture of 600 mm developed by China. According to the data of International Laser Ranging Service (ILRS), the observation data of this station ranks in the top five in the world, which is very important for the international laser ranging system.

In the 24th China Antarctic scientific expedition, China astronomers successfully installed astronomical observation and field measurement instruments including CSTAR (China Small Optical Telescope Array) in Dome A. The development of this work provided a rare opportunity for China's research in frontier scientific fields such as dark matter, dark energy and exoplanet detection to reach the world advanced level.

Looking forward to the future, China will also open up space astronomy and Antarctic astronomy, and participate in the international cooperation of 30-meter optical/infrared telescopes on the ground, which will open up a broader development prospect for China's astronomical development and make China's astronomical research firmly occupy a place in the international advanced level.

The picture above shows the 40-meter-diameter radio telescope of Yunnan Observatory. It cooperates with Beijing Miyun 50-meter-diameter antenna to form the only deep space (moon) detector data receiving ground station system in China, and undertakes the tasks of data receiving and orbit observation in the implementation of a series of lunar exploration projects in China.

The picture below is a schematic diagram of the Space Solar Telescope (SST). Its main purpose is to understand the characteristics and essence of solar activity and achieve a major breakthrough in solar physics research.