Photometry of Venus: III. Interpretation of brightness distributions over the disk

A series of solar brightness distributions observed over the Venus disk at several wavelengths is analyzed. A single absorption mechanism is assumed, the main localization of which is varied within the clouds, in different models. An attempt is made to retrieve all of the observations from one or more of the models. From the ultraviolet observations, models in which the absorption is highly localized give a better fit although better measurements are needed before a definite conclusion may be drawn. Isophote maps in visible light disagree with the theoretical predictions of all the models, suggesting that a second absorption mechanism (perhaps the ground) ought to be called for in this spectral region.