An analysis of satellite STP78-1 measurements at solar maximum of the latitudinal variation of O I EUV dayglow emissions at 1356, 1304 and 989 ¿ is presented. The dayglow intensity measurements corroborated by Atmosphere Explorer-E data indicate that the exospheric temperature was about 220--240 K higher than predicted by the MSIS-83 thermospheric model. In addition, the temperature variation with latitude is not as large as predicted by the MSIS-83 for day 80, 1979. The 1304- and 1356-¿ intensity measurements are consistent with electron impact excitation cross-section measurements of Zipf and Erdman (1985). The 989-¿ excitation cross section of Zip and Erdman (1985) requires a branching radio of 7¿10-4 for transitions other than 989-¿ in order to produce agreement with our data. The Vaughan and Doeng (1987) direct 3s' 3D0 excitation cross section, about a factor of 3 smaller than the optical excitation cross section of Zipf and Erdman (1985), is also compatible with our 989-¿ data for a branching ratio near 1¿10-4. The solar 1304-¿ spectral irradiance inferred from the observations is about a factor of 2 lower than the rocket measurements of Mount et al. (1980), but is consistent with Solar Mesosphere Explorer results. Our measurements also suggest that enhancement of the 1304-¿ electron impact excitation cross section due to radiative entrapment of cascade-feeding photons is negligible. ¿ American Geophysical Union 1988