Editing Xi'an (section)

===National Time Service Center===
The [[National Time Service Center|Shaanxi Astronomical Observatory]] was established in 1966. In 1975, according to the Geodetic Origin Report of the People's Republic of China, 'in order to avoid bias in the mensuration as much as possible, the Geodetic Origin would be in central mainland China.' Lintong ({{lang|zh-hans|临潼}}), a town near Xi'an was chosen. Since 1986, Chinese Standard Time (CST) was set from NTSC. The National Time Service Center (NTSC), the Chinese Academy of Sciences is an institute which is mainly engaged in the service and research on time and frequency. NTSC takes charge of generating and maintaining the national standard time scale, disseminating the time and frequency signals. The autonomous standard time scales of universal time and atomic time and the dissemination techniques with LF radio and HF radio were established successively during the 1970s and 1980s, which meet all the requirements for different applications on the whole, such as the scientific researches, national economy, etc.<ref>[http://www.time.ac.cn/jianjie/1.htm NTSC] {{webarchive |url=https://web.archive.org/web/20160304001755/http://www.time.ac.cn/jianjie/1.htm |date=March 4, 2016 }} 国家授时中心简介</ref>