Lateral inhomogeneities in the Venus atmosphere - Analysis of thermal infrared maps

The thermal infrared maps of Venus published by Murray, Wildey, and Westphal (1963) and Westphal, Wildey, and Murray (1965) have been analyzed systematically in order to separate the observed intensity into a limb-darkening component and a solar-associated component representing fixed patterns of intensity corotating with the earth and sun, respectively. Interesting new results are obtained for the solar-associated component. Regions near the subsolar point and the poles are not covered in the original maps or in the analysis. The solar-associated pattern of intensity is very nearly symmetric about the equator. In both northern and southern hemispheres, an intensity minimum seems to occur near the morning terminator at middle to high latitudes, slightly beyond the limit of the maps. An intensity maximum occurs on the equator slightly to the east of the antisolar point.