A Tentative Model of the Venus Atmosphere Based on the Measurements of Veneras 5 and 6

Abstract

Following the flight of Venera 4 in October 1967, new in-situ measurements of the temperature, pressure and density of the Venus atmosphere were made on 16 and 17 May 1969 by the Venera 5 and 6 space probes. A description of the scientific devices and an analysis of the results of the data are presented. From the results it is concluded that all measurements performed are, in general, internally consistent. The data of the Venera 4, 5 and 6 and Mariner 5 flights which overlap in altitude agree quite well. Based on these spacecraft measurements, and taking into account some ground-based data and some additional assumptions, a tentative model of the Venus atmosphere is developed from the surface up to 300 km. The extrapolated values of temperature and pressure at the mean level of the planetary surface, taking into account possible large deviations from the adiabatic model, result in a surface temperature of 770±60K and a surface pressure of 97₋₃₀⁺¹⁵ atm, respectively.