|airglow (âr'glō') Pronunciation Key
A faint photochemical luminescence in the upper atmosphere caused by the collision of x-rays and charged particles from the Sun with atoms and molecules, especially of oxygen, sodium, and the hydroxyl radical (OH). Airglow is strongest over low and middle latitudes.
weak, widespread, and relatively steady glow from the sky that is observed around twilight; it is part of the overall phenomenon called airglow (q.v.).
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