Variability of the mesospheric nightglow during the 2002 Leonid storms

There was no significant increase in the intensities of three prominent components of the terrestrial nightglow during the 2002 Leonid storm peaks. The atomic oxygen line at 557.7 nm, the sodium D lines at 589.0 and 589.6 nm, and the OH(6,2) band at 826–862 nm were monitored using an airborne spectrometer over the North Atlantic (40–50°N). The results indicate that the meteor storm produced a negligible change in both atomic sodium and oxygen compared to the background concentrations. The spectrometer resolved the sodium doublet, and showed that the ratio of the D2 and D1 lines is not 2.0, as had been thought hitherto, but is highly variable on distances of a few tens of kilometers. The mean value is about 1.8, with values ranging from 1.3 to 2.4.