Observations of the 6300-¿ nightglow from the Visible Airglow (VAE) instrument on AE-E are presented for spring equinox, solar cycle maximum conditions. The data comprise altitude profiles and integrated column brightness maps from ~1800 to 0400 LT and within ¿30¿ of the dip equator. The data clearly show near-midnight enhancements of the 6300-¿ emission. Attempts to model the column brightness maps indicated that these enhancements are due to tidal effects: the enhancements were only reproduced in the theoretical calculations which included upward propagating tidal components in the neutral winds. Further, low equatorial intensities were observed by the VAE which could only be simulated by assuming that the phase of the E¿B drift be shifted 1 hour LT; i.e., upward drift persists until 2000 LT instead of 1900 LT. The VAE observations could be reasonably simulated with the phase shift in the E¿B drift and with the dip and geographic equators offset. The major discrepancy is in the magnitude of the nightglow maxima; the calculated intensities are a maximum of 2 times too large. Possible sources are uncertainties in the neutral densities, chemistry, and rate coefficients and in the neutral winds. ¿ American Geophysical Union 1987 |