PURPOSE: To dock a spacecraft to an objective artificial satellite by operating a gripper with observing a monitor image receiver.

CONSTITUTION: A spacecraft 1 on which a TV camera 11 is loaded should be roughly aligned to project a target mark setting plate of an artificial satellite 2 on a monitor image receiver. Then a gripper 18 should be operated to overlap an image of target mark 20 on an image of target mark 3 in a monitor 16. Thus by simulating the relative location of the satellite 2 observed from the spacecraft 1 on the monitor image receiver, the objective position of the spacecraft 1 can be aligned to the satellite 2. Consequently, an operator 17 is required only to adjust the image of the target mark 3 displayed on the monitor image receiver 16 to the position and size to allow docking. Even though the operator has no detailed knowledge of the characteristics of propelling unit or control features of the spacecraft 1, smooth and reasonable operation can be realized.