Data from scanning photometers equiped with fixed interference filters selecting the P and R branches of the N2+ first negative (0--1) band were used to derive the temperature height profile through an auroral arc. The height of the arc was determined by two-station triangulation techniques. The accuracy of the temperature determination is related to the relative intensity of the background aurora compared to the intensity of the arc. The need for a critical selection of the appropriate event to be analyzed and of the background to be subtracted is an important consideration in the analysis. In this particular example the most reliable part of the derived temperature profile lies between 105 and 140 km, and in this interval the temperatures agree well with the atmospheric temperature profile given by the U. S. Standard Atmosphere (1966) at 800¿ K exospheric temperature. No heating of the neutral atmosphere within the auroral arc was found.