A method and system for a mobile station to determine its position (or velocity) and time using a hybrid combination of satellite orbit data. In one aspect, the mobile station combines predicted orbit data from one satellite and real-time orbit data from another satellite in the determination of a fix. The combination can be made to the satellites in the same or different satellite systems. The mobile station can use the real-time orbit data of a satellite at one time period and the predicted orbit data of the same satellite at another time period. In another aspect, the mobile station can use the real-time orbit data to correct the clock bias in the predicted orbit data. The correction to the clock bias can be made to the same satellite that provides the real-time orbit data, or to a different satellite in the same or in another satellite system.