Nightglow on Venus
These intervals could be explained by the time needed for the oxygen atoms in downward movement to cover the fifteen or so kilometres separating the layers of ultraviolet emissions of NO and infrared of O₂: this very long time (several Earth days) leaves plenty of time for the horizontal wind to transport the atoms over great distances (several thousand kilometres).
The verification of this hypothesis involves quantifying physical and chemical processes which come into play in the formation of nightglows and, in particular, the role of an eventual coupling between the horizontal and vertical components of the winds. Given the multitude of these processes, the problem can only be approached numerically. This was precisely the subject of the master thesis of Arnaud Collet, who has just been published in the Éditions Universitaires Européennes(1).
(1) Arnaud Collet, Dynamique et chimie dans l’atmosphère de la face nocturne de Vénus, Editions Universitaires européennes, 2010.