NO2 continuum in aurora

Rocket measurements of the vertical profile of the NO 2 continuum in low‐ to medium‐intensity aurorae give intensities at 5200 Å of the order of 1.0 R/Å. By using atomic oxygen densities deduced from the quenching rate of the N 2 (A³Σ u + ) state NO densities of the order of 1 to 4 times 10 9 cm −3 are found at 110 km. NO densities deduced from the measured NO + / O 2 + ratio tend to confirm these abundances.