What is the number of digits of xy coordinate in geodetic coordinate system 2000?

Xy coordinate digits of geodetic coordinate system 2000: 8 digits.

Brief introduction of 2000 national geodetic coordinate system;

The origin of the 2000 national geodetic coordinate system is the center of mass of the whole earth, including the ocean and atmosphere; The Z-axis of the 2000 National Geodetic Coordinate System points from the origin to the direction of the Earth's reference pole of 2000.0 epoch, which is calculated in 1984.0 epoch according to the initial direction given by the international situation.

Directional time evolution ensures that there is no residual global rotation relative to the crust. The X axis points from the origin to the intersection of Greenwich reference meridian and the equatorial plane of the earth (2000.0), and the Y axis, Z axis and X axis form the right-handed orthogonal coordinate system. Adopt a scale in a relative sense.

Since the founding of New China, China established the Beijing coordinate system of 1954 and the Xi 'an coordinate system of 1980 in 1950s and 1980s respectively, and made topographic maps of various scales, which played an important role in national economy, social development and scientific research. Limited by the technical conditions at that time, China's geodetic coordinate system was basically realized by traditional technical means.

54 coordinate system adopts Krasovsky ellipsoid. In the calculation and positioning process, the ellipsoid does not use the data of China, and the system is not suitable for China, so it cannot meet the needs of high-precision positioning and the development of earth science, space science and strategic weapons.

In the 1970s, after more than 20 years of hard work, Chinese geodetic workers finally completed the layout of the national first-class and second-class astronomical geodetic network.

After overall adjustment, Xi 'an coordinate system 1980 was established in China by using the reference ellipsoid parameter 1975 recommended by the 16th IUGG Congress. Xi 'an coordinate system 1980 has played a great role in China's economic construction, national defense construction and scientific research.

With the progress of society, national economic construction, national defense construction, social development and scientific research put forward new requirements for the national geodetic coordinate system, and it is urgent to adopt the coordinate system with the center of mass of the earth as the origin (hereinafter referred to as geocentric coordinate system) as the national geodetic coordinate system.

Using geocentric coordinate system is beneficial to maintain and update the coordinate system quickly by using modern aerospace technology, determine the high-precision three-dimensional coordinates of geodetic control points and improve the mapping efficiency.