1. A method for determining a relative position of an object in space in six spatial degrees of freedom, the method comprising: applying a marking pattern with at least three markings on the object; providing an optical detection apparatus with a two-dimensional sensor surface; moving the object in a detection region of the optical detection apparatus in such a way that the marking pattern is detectable by the detection apparatus; projecting the markings onto assigned image locations on the two-dimensional sensor surface; establishing image coordinates of the image locations, associated with the markings, on the sensor surface; determining a relative position of the marking pattern by evaluating the image coordinates using an evaluation method comprising: selecting a first image location and a second image location, wherein the first image location is assigned to a first marking and the second image location is assigned to a second marking of the marking pattern; wherein a first vector between a projection center of the detection apparatus and the first image location and a second vector between the projection center and the second image location include a first angle and span a reference plane, and wherein a perpendicular projection of a third image location, associated with a third marking, on the reference plane defines a foot of the third marking; and establishing a location of a fixed point, wherein the location of the fixed point is constant, independent of the location of the projection center and the location of the foot, and a connecting straight line through the projection center and the foot always extends through the fixed point, wherein a reference circle is established, which extends through the first marking, the second marking and the projection center and has a center, and wherein the location of the fixed point on the reference circle is established.