Satellite ranging method and apparatus

An embodiment of the invention provides a satellite range finding method and an apparatus thereof. The method comprises the following steps: a satellite emits a laser beam to a ground with an angle theta at t time at S point, the satellite flies with speed v, at M point the satellite receives a laser beam returned by the ground, and a time interval Delta t between the time of the satellite emitting the laser beam and the time of the satellite receiving the laser beam is measured; attitude error parameters of the satellite at t time are measured, and the parameters comprises a pitch angle alpha and a roll angle beta. According to the laser beam emitted by the satellite and received by the satellite, the time interval Delta t and the attitude error parameters, a range finding result of the satellite is calculated. According to the embodiment of the invention, in the case of considering the satellite attitude error and a range finding error caused by the flight speed, the range finding result of the satellite is obtained.