THE MIDDLE ULTRAVIOLET DAYGLOW SPECTRUM

Spectroscopic measurements of the thermospheric dayglow in the wavelength range 1900 to 3400 Angstrom are presented. These measurements were made during two rocket experiments conducted on March 30, 1990, and March 19, 1992, from White Sands Missile Range, New Mexico. The data are presented to provide reference spectra in the lower, middle, and upper thermosphere. The 1990 observations, which were made during high geomagnetic activity, showed considerably enhanced nitric oxide (NO) intensities. Self-absorption theory is applied to the upsilon'' = 0 bands of the NO gamma system, It is found that a recently published self-absorption algorithm correctly accounts for the attenuation of the gamma(1,0) bands. There is a small discrepancy between the theory and observation for the (2,0) band and the (0,0) band intensity. The fact that there is reasonable agreement for all three bands suggests that both the NO slant column density and oscillator strengths for these bands are correct.