A method for determining a direction of a spin axis of a rotating apparatus which includes an XYZ-magnetic field sensor. The method includes determining a global direction of a magnetic field; rotating the rotating apparatus around the spin axis, measuring at least one magnetic field value as a function of time with the XYZ-magnetic field sensor when the rotating apparatus is rotating about the spin axis, computing a magnetic field component of the magnetic field in a direction of a local body co-ordinate of the spin axis of the rotating apparatus from the measured at least one magnetic field value and determining a direction of the spin axis using the computed magnetic field component of the magnetic field and the determined global direction of the magnetic field.