A method for contactlessly determining the temperature of a moving object having an unknown degree of emission, especially a metal wire conveyed along its longitudinal axis, comprising the steps: - The object is guided through at least one radiation source (12, 48, 56) emitting thermal radiation of known temperature, wherein the object is mostly or completely surrounded by the at least one radiation source (12, 48, 56), - with at least one radiation detector, a spatially-resolved thermal radiation measurement is performed in a region through which the object passes when it is guided through the at least one radiation source (12, 48, 56), wherein the at least one radiation detector detects the radiation of the at least one radiation source (12, 48, 56) in addition to the object to be measured in its background, - the temperature of the moving object is measured on the basis of the spatially-resolved thermal radiation measurement, by evaluating a difference between the measured thermal radiation emitted and possibly reflected by the at least one radiation source (12, 48, 56), and the measured thermal radiation emitted and reflected by the moving object, - wherein the at least one radiation source (12, 48, 56) comprises a cavity radiator with an inlet opening and an outlet opening, wherein the object is guided through the inlet opening and the outlet opening through the cavity radiator, and wherein the cavity radiator comprises at least one measuring opening through which the spatially-resolved thermal radiation measurement occurs, characterized in that - the radiation detector for the spatially-resolved measurement detects a first region through the measuring opening in which the moving object is located below the measuring opening viewed perpendicular relative to its direction of movement, as well as a second region in which the moving object is not below the measuring opening when viewed perpendicular to its direction of movement, and - a position of the moving object is determined using the measured values from the first region and a position of the moving object in the second region is deduced therefrom, wherein the thermal radiation emitted and reflected by the moving object measured in this position of the second region is used to form the difference. - The object is guided through at least one radiation source (12, 48, 56) emitting thermal radiation of known temperature, wherein the object is mostly or completely surrounded by the at least one radiation source (12, 48, 56), - with at least one radiation detector, a spatially-resolved thermal radiation measurement is performed in a region through which the object passes when it is guided through the at least one radiation source (12, 48, 56), wherein the at least one radiation detector detects the radiation of the at least one radiation source (12, 48, 56) in addition to the object to be measured in its background, - the temperature of the moving object is measured on the basis of the spatially-resolved thermal radiation measurement, by evaluating a difference between the measured thermal radiation emitted and possibly reflected by the at least one radiation source (12, 48, 56), and the measured thermal radiation emitted and reflected by the moving object, - wherein the at least one radiation source (12, 48, 56) comprises a cavity radiator with an inlet opening and an outlet opening, wherein the object is guided through the inlet opening and the outlet opening through the cavity radiator, and wherein the cavity radiator comprises at least one measuring opening through which the spatially-resolved thermal radiation measurement occurs, characterized in that - the radiation detector for the spatially-resolved measurement detects a first region through the measuring opening in which the moving object is located below the measuring opening viewed perpendicular relative to its direction of movement, as well as a second region in which the moving object is not below the measuring opening when viewed perpendicular to its direction of movement, and - a position of the moving object is determined using the measured values from the first region and a position of the moving object in the second region is deduced therefrom, wherein the thermal radiation emitted and reflected by the moving object measured in this position of the second region is used to form the difference.