Metastable oxygen O(1S) Martian airglow: observations and model

Limb profiles of OI 297.2 nm dayglow observed with IUVS/MAVEN show seasonal and latitudinal variations of the intensity and altitude of both peaks. The production of O(1S) atoms in the Martian upper atmosphere is dominated by photodissociation of CO2 at all altitudes below 200 km.
The lower peak is produced by penetration of Ly-α solar radiation down to the 80 km region. The quantum yield for O(1S) production by CO2 dissociation by Lyman-α is about 10%.
The 297.2 nm emission changing peak altitude reflects variations of the CO2 column density and thus the pressure level