The Ultraviolet Nitric-Oxide Experiment (UVNO) consisted of a two-channel fixed-grating Ebert-Fastie spectrometer which measured the airglow. The observed intensity was produced by resonance fluorescence of sunlight by the nitric-oxide molecules in the instrument’s field of view. The intensity profiles obtained yielded altitude profiles of nitric-oxide density as a function of time and location. Profiles were measured along the track of the satellite at times when it was on the sunlit side of the earth. The remote sensing character of the UVNO experiment permitted measurements of nitric-oxide to be made at altitudes both above and below satellite perigee. This instrument was part of the AE-C and AE-D missions.