First detection of hydroxyl in the atmosphere of Venus

Context. Airglow emissions, such as previously observed from NO and O (0-0) on Venus, provide insight into the chemical and dynamical processes that control the composition and energy balance in the upper atmospheres of planets. The OH airglow emission has been observed previously only in the Earth's atmosphere where it has been used to infer atomic oxygen abundances. The O (0-1) airglow emission also has only been observed in the Earth's atmosphere, and neither laboratory nor theoretical studies have reached a consensus on its transition probability.