THE TWILIGHT CUSP EXTENSIONS OF VENUS,
RAND CORP SANTA MONICA CALIF
Pagination or Media Count:
It has been known since about 1790 that when Venus is near inferior conjunction, the cusps of her crescent extend far beyond a half-circle. It is further known that Venus, at greatest elongation, does not present the expected half-moon shape, but rather appears convex towards the illuminated side. This leads to a discrepancy of the order of days between date of apparent and geometric dichotomy, not satisfactorily explained to date. On the basis of our study, we are forced to infer that the scattering atmosphere of Venus extends to considerable heights above the cloud deck, and that its luminosity characteristics are not too far different from those of the earths atmosphere. Height variations of the scattering atmosphere itself appear therefore to be immaterial, but small height variations of the probably uneven top of the opaque cloud deck would explain observed effects.