Recalculated Polar Motion Data on Homogeneous System of International Latitude Service

Acting as the international latitude measurement service(ILS), this international joint measurement of latitude was carried out from 1899 to 1978. The ILS central station(Mizusawa) used the measured data, and expressed the change of latitude at all the observatories by a uniform system. This sytem is independent of the error in the positions of stars and the error in instrument constants. In this file, the coordinate values of polar motion(X, Y) have been recorded with the unit of angular second.