Sanya coordinate is less than 2000 coordinate because Sanya coordinate is the only relatively independent plane coordinate system in Hainan. According to relevant data, the 2000 National Geodetic Coordinate System is a geocentric geodetic coordinate system with the center of mass of the earth as the origin, which is different from Hainan. Coordinates, mathematical nouns. Refers to the spherical coordinate system established on the celestial sphere to determine the position of a point on the celestial sphere.