2000 National Earth Coordinate System

China's 54 Beijing coordinate system and 80 Xi'an coordinate system adopted the coordinate system origin, coordinate axis direction and so on due to the limited level of science and technology at that time, its origin and Earth mass center has a large deviation, the relative precision of the Earth control points in the coordinate system is only-6 to the power of 10, causing loss of precision, unable to fully meet the requirements of today's meteorological, seismic, water conservancy, transportation and other departments for high-precision surveying and mapping geographic information services, it will adopt a new generation, more accurate 2000 National Land coordinate system.

This is the location of the Earth origin in the 80 coordinate system of the previous generation. (Reposted from Sohu)

The "Land origin of the People's Republic of China" is located in Shiji temple village, Yongle town, Jingyang County, Shaanxi Province, and 40 kilometers away from Xi'an NATO. (), Also known as (), is used to calculate the start point of the coordinate in the national horizontal control network. The Earth origin is a point defined by humans. We can use it to precisely know where our geographic location is. Therefore, the so-called GPS Global Positioning System makes sense. It took a long time for scientists to determine the origin point. Since then, any inch of land in China can be identified with precise Earth coordinates. In the 1970s s, China decided to establish its own independent geocoordinate system. Through on-site investigation and comprehensive analysis, the land origin of our country will be determined within the territory of Shiji temple village, Yongle town, Jingyang County, Xianyang city. The origin, that is, the "", is the starting point for the calculation of the coordinate in China's horizontal control network. It not only plays an important role in construction and science and technology, but also symbolizes the dignity of the country. The geocoordinate calculated by the origin is called "". The center of the origin Hall is a cylindrical cylinder about 2 m in diameter. The upper part of the cylinder is inlaid with a rectangular black marble with the golden character "origin of the People's Republic of China. There are 8 columns around the cylinder, and the material is a red marble veneer of about 0.5 in diameter. The height of the hall on the first floor of the origin is determined by the distance between the first observation point of the Earth's origin. You can go up the stairs to the top and down to the basement where the source stone is located. This is the marker of the roof. When you enter the iron door in the basement, you can see the source stone covered in the glass frame. It is introduced as a whole rock. The plaque at the entrance of the hall introduces the land origin of the People's Republic of China, which is the benchmark of the national coordinate system (1980 Xi'an Coordinate System) and plays an important role in China's economic construction, national defense construction and social development. This origin was established in December 1978. It covers an area of 3.92 hectares and consists of the main building, central sign, instrument table, and projection pavilion. The central coordinate of the origin is 34 ° 32' north latitude, 108 ° 55' east longitude, and the altitude is 417.20 meters. Background information: a relatively moderate point is usually selected as the origin in the National Geographic Network, and its Astronomical Latitude and longitude and Astronomical Azimuth to another point are measured with high precision. Based on the positioning method of the "reference elliptical, obtain the latitude and longitude of the Earth, the height of the earth, and the azimuth angle of the Earth to another point. These data are called "". In the early days of the founding of the People's Republic of China, the geometric coordinate system was jointly tested from the former Soviet Union, and its coordinate origin was the former Soviet Union's boerkov Observatory. This situation is extremely incompatible with the construction and development of our country. To this end, the relevant national authorities decided to establish China's independent geocoordinate system. In the 1970s s, China began to organize manpower, collect and analyze a large amount of data, and according to the requirements of "Origin, on-site investigation and comprehensive analysis of topography, geology, geostructure, astronomy, gravity, and geomeasurement in Zhengzhou, Wuhan, Xi'an, Lanzhou, and other places, finally, the Earth origin is located in the Shiji temple village, Yongle town, Jingyang County, Shaanxi Province. According to the land origin Selection Report of the People's Republic of China, in order to evenly calculate the land survey results, the origin is best in the central part of China's mainland. The Shiji temple village in Yongle town, Jingyang County, Shaanxi Province is 880 km north of China's border, 2500 KM northeast, 1000 km east, 1750 km south, and 2250 km southwest, it is 2930 kilometers away from the west and 2500 kilometers away from the northwest. It is located in the central part of the Mainland China, and thus has the land origin of China.