The Shanghai Astronomical Observatory (SHAO) of the Chinese Academy of Sciences (CAS), was established in 1962 following the amalgamation of the former Xu Jiahui and Sheshan observatories, which were founded by the French Mission Catholique in 1872 and 1900, respectively. Both came under the Chinese government jurisdiction in 1950.
         The observatory launched its time service at Xujiahui in 1884, and began radio broadcasting time signals in May 1914. A pair of 40cm refractive binoculars was built in 1900 on the hilltop of Sheshan, which has twice observed the return of the Halley's Comet as the largest optical telescope in East Asia at that time. The observatory joined the international longitude determination activities in 1926 and 1933 as one of the three world longitude reference points. On the invitation of the Royal Greenwich Observatory, the Sheshan observatory participated in the international cooperation of lunar occultation in 1930. The observatory began transmitting time signals in 1954 using the BPV time/frequency standard, thus marking the birth of modern time service in China. At the end of the 1950s, the observatory started to build a comprehensive universal time service network jointly with other observatories in China, and established the country’s universal time reference through continual gradual development and improvement.
         Around the mid-1960s, SHAO took on the task of promoting the accuracy of its universal time to the front ranks of the world, and has maintained its international high level ever since. The observatory successfully developed its hydrogen clocks in the mid-1970s. To meet the need of the country, China began moving west its time service around the end of the 1970s, when the Shanxi Astronomical Observatory was founded to undertake the mission of providing time service.
         Since 1998, the Party Central Committee and State Council made a major decision to set up a national innovation system, and decided to let CAS launch a pilot program for knowledge innovation engineering. The near- and long-term development goals of SHAO were further clarified around the CAS policies of “Innovation Project ?     Phases 1, 2 and 3” and “Gear to the World’s Science Frontiers; Gear to the National Strategic Need”. The observatory will strive to provide support in science and technologies for astronomical observation and research as well as national strategic need, taking astrophysics and astro-geodynamics as the main directions of academic study while actively developing modern astronomical observation and time/frequency techniques. In basic research, SHAO will try hard to become a first-rate highly competitive international research center. In applied research, the observatory will play a key role in the country’s major navigation/positioning, deep-space exploration and time/frequency projects. Based on the observatory’s own distinguishing features and the country’s current state of development, SHAO will try to condense the specific substance of its “Two Gear-To” policy: “Gear to the World’s Science Frontiers” will focus on astro-geodynamics, galaxies & cosmology, and astronomical observation techniques, while “Gear to the National Strategic Need” will be centered mainly around lunar and deep-space explorations, navigation and positioning, and time/frequency techniques.
       In the mid-1980s, a Very Long Baseline Interferometry (VLBI) system and a second-generation Satellite Laser-Ranging (SLR) system were successively built, followed by the completion of a 1.56m astrometric telescope that was fully developed and put into operation. These facilities led to the establishment of an information analysis and data processing system that can effectively handle five types of observation techniques, namely classical and new Doppler measurements, SLR, VLBI and LLR (Lunar Laser-Ranging).
        In the early 1990s, the Chinese Academy of Sciences (CAS) proposed new policies for administrating the academy and adopted a new “One Academy, Two Systems” operating mode. Adhering to these principles, the observatory suggested the following guidelines: meticulously streamline its basic research teams; clarify its directions of academic disciplines; properly split-flow its human resources; and reform its management system so that basic research can be more efficiently carried out in the carefully chosen main directions.
         Academy Member YE Shuhua initiated and headed a National Major Basic Research (“Climb”) Program entitled “Present-day Crustal Motion and Geodynamics Research”, which was jointly undertaken by the CAS, State Seismology Bureau, State Bureau of Surveying and Mapping, and related units of the General Staff’s Bureau of Surveying and Mapping. SHAO has made significant achievements at international advanced levels in areas such as: monitoring and research in the continental crustal motion in the Chinese mainland; establishing and maintaining a high-precision earth reference system; variations in earth rotation; dynamics of the Qinghai-Tibetan Plateau; variations in the gravitational field and sea level in China; and forecasting natural disasters. These accomplishments have become the driving force for establishing the international cooperative program APSG (Asian-Pacific Space Geodynamics) hosted by SHAO. The observatory has also participated in another National Major Basic Research (“Climb”) Program known as “Multi-Band Observation and Analysis of Violent Celestial Activities”. In-depth investigations have been conducted in a number of areas, including VLBI research in AGN (Active Galactic Nuclei), starburst galaxies, multi-band observation and research in AGN, variable and unstable stars, etc.