Abstract: An object mounted on a carrier constitute a rotationally free system such as a telescope on a space vehicle. A separation vector is directed from the center-of-mass of the carrier to the center-of-mass of the object. The object is rotated through a selected angle thereby defining a rotation vector. Simultaneously the object is translated so as to displace the object center-of-mass through a translation distance in a direction such that mathematically crossing the translation vector into the separation vector results in a further vector having the same direction as the rotation vector. A formula is provided for the translation distance in order that the object may be rotated without counter-rotation of the carrier.