Measurements of atmospheric trace gases have been performed during the first Spacelab mission, on board the Space Shuttle, from 28 November to 8 December 1983. The principle of the observations is absorption spectroscopy, in the infrared, using the sun as a light source during sunset or sunrise periods. The instrumental set-up and the flight operations, already described in previous papers, are briefly summarized. The automatic retrieving method for the processing of the spectra is explained. Finally, all the results, in terms of vertical concentration profiles, are given for NO, NO2, CH4, N2O, CO, CO2 and H2O. Several results have been published (Laurent et al., 1985, Nature315, 126; Muller et al., 1985a, J. Optics (Paris) 16, 155 ; 1985b, Geophys. Res. Lett.12, 667 ; Vercheval el al., 1986, Ann. Geophys.4A, 161 ; Laurent et al., 1986, Planet. Space Sci.34, 1067). This last version may be slightly different, due to recently available and more accurate orbital parameters.