History Manuscript of Purple Mountain Observatory

Author: Jiang Xiaoyuan, Wu Yan
Publisher:
Publish Date: 2004-12-01
Features: The Purple Mountain Observatory, established in September 1934, is China's first modern astronomical research institution, marking the beginning of modern astronomy research in China and serving as the cradle of modern Chinese astronomy. The material in this book is authentic and comprehensive, extensively citing original literature to vividly recreate the epic efforts and inner journeys of the astronomers. The Purple Mountain Observatory was built by Chinese astronomers themselves, representing a modern astronomical observatory in the true sense. Although its history is not long, strictly speaking, only it truly represents the "modernization of Chinese astronomy"—the previous Xujiahui Observatory and Qingdao Observatory were essentially astronomical observatories built by Europeans, merely located in the Far East. The Purple Mountain Observatory is a successful case of Chinese astronomers laying the foundation for their own modern astronomical system from scratch. The authors of this book have not only referenced various published and unpublished books and journals but have also conducted extensive research in archives such as the Purple Mountain Observatory, the National Historical Archives of China (Beijing), and the Second National Historical Archives of China (Nanjing), acquiring extremely valuable historical materials. Based on this, the book extensively cites original literature to vividly recreate the epic efforts and inner journeys of the astronomers.
Excerpt: The Purple Mountain Observatory established the Astrophysics Group in 1953, the Astrophysical Evolution Group in 1957, and the Stellar Laboratory in 1961, primarily engaged in stellar physics and evolution; the Solar Physics Research Laboratory in 1958, primarily focused on solar physics research, applied research, and solar forecasting; and the Theoretical Astronomy Research Laboratory in 1980, primarily engaged in astrophysical mechanics and plasma astrophysics research. The Astrophysics Research Department was established in 1997, primarily focused on cutting-edge astrophysical research and fundamental theoretical studies. The Purple Mountain Observatory has made many pioneering and internationally renowned contributions in the field of astrophysics, achieving a series of observational and theoretical results:
· Non-local convection theory and the structure and evolution of stars, awarded the First Prize of the Natural Science Award by the Chinese Academy of Sciences in 1989 and the Second Prize of the National Natural Science Award in 1991. Completed by: Purple Mountain Observatory. Stellar convection is an important fundamental theory in astrophysics. Currently, the only applicable phenomenological theory internationally is the mixing-length theory. It encounters severe difficulties when dealing with convection overshoot. The authors developed a statistical theory of non-local convection and successfully applied it to theoretical calculations of the structure of the solar convection zone and the evolution of massive stars. Overcame the famous theoretical difficulties of semi-convection. Observations support the new non-local convection theory.
· Observation and research on Halley's Comet, awarded the First Prize of the Natural Science Award by the Chinese Academy of Sciences in 1989 and the Third Prize of the National Natural Science Award in 1991. Completed by: Purple Mountain Observatory, Beijing Observatory, Yunnan Observatory, Shanghai Observatory, etc. During the 1985/86 return of Halley's Comet, a large number of valuable observational results were obtained, with over 90 papers published. Precise positioning contributed to the success of the international Halley Comet space exploration. The observed phenomena such as the broken tail, nucleus outburst, and the initial appearance of the plasma tail have high academic value and have been widely cited and highly evaluated by international peers. This work holds a relatively important position in the study of Halley's Comet return.
· Joint observation and data analysis of the 21st solar activity peak year, awarded the First Prize of the Science and Technology Progress Award by the Chinese Academy of Sciences in 1986. Completed by: Purple Mountain Observatory, Beijing Observatory, Yunnan Observatory. From 1980 to 1982 during the 21st solar peak, Purple Mountain Observatory, Beijing Observatory, and Yunnan Observatory conducted joint optical and radio solar observations and comprehensive research on flares. Obtained comprehensive data on 15 large active regions and their large flares, with a total of more than 30 papers on flares with Chinese characteristics published domestically and internationally. Proposed new insights into the origin and energy release of flares, attracting attention from the international solar community.
The Purple Mountain Observatory has achieved many important theoretical results in the field of astrophysics frontiers and fundamental theoretical research:
· Developed a statistical theory of non-local and non-stationary stellar convection and applied it to theoretical calculations of the solar convection zone structure, the evolution of massive stars, and the pulsation of variable stars. Overcame the famous theoretical contradictions of semi-convection, explained the theoretical difficulties of the red (low-temperature) boundary of the instability region of variable stars, and correctly predicted the main observational properties of the solar atmospheric flow velocity field and temperature field, as well as the structure of the solar convection zone.
· Extracted non-thermal electron energy spectra and cutoff energy information from radio frequency spectrometers and theoretically proved the criteria for the existence of cutoff energy. Studied the theoretical reconnection of weakly ionized gases, discovered and established a set of rigorous analytical solutions, and developed formulas for calculating the source region magnetic field under transverse propagation conditions. From both theory and helioseismology, studied the possibility of the existence of internal solar magnetic fields, the relationship between the solar cycle and Earth's climate, and the influence of turbulent pressure on helioseismic (astroseismic) P-mode frequencies. Space satellite observations confirmed the electromagnetic field, phase velocity, and density hole characteristics of a new type of plasma dynamic Alfvén wave, and conducted in-depth theoretical research. The results are of great significance for the acceleration of solar and heliospheric plasma, as well as the spatial structure of density and electromagnetic fields generated thereby, and have been cited multiple times by international peers.
· Studied the evolution of r-process fireball matter, proposed a unified model for the fireball transitioning from extreme relativistic to non-relativistic states, and found that only when the jet opening angle is very small (less than 0.1) will a clear inflection point appear in the light curve, which can be used to constrain the energy of r-processes. First conducted a detailed study of the impact of inverse Compton scattering on r-processes and afterglows. Studied the photon fission process on the surface of a neutron star with a strong magnetic field and found that when the magnetic field exceeds 10^13 Gs, the photon fission process will suppress pulsar radiation, making it difficult to observe radio emissions. Proposed a new model for the r-process burst from the phase transition of a neutron star to a strange star, which can better explain the correlation between r-process bursts and supernova explosions. Offered a new explanation for the steepening of afterglow light curves. Conducted statistical studies on X-ray binary systems, compiling catalogs of massive and low-mass X-ray binaries, which have been collected by NASA's High-Energy Astrophysics Science Archive Research Center, making significant international contributions.
· Published a monograph titled "High-Energy Astrophysics of the Sun." High-energy astrophysics is a new discipline, and prior to this, no specialized monograph existed internationally. The frontiers of astrophysics and fundamental theoretical research are one of the key development directions of the Purple Mountain Observatory. Currently, it is undertaking multiple national major and key projects, as well as international cooperation projects. The Purple Mountain Observatory will continue to focus on the forefront of international science and technology, broaden its research fields, further enhance international cooperation and exchange, and strive for greater achievements.