VIRA-2: A review of inputs for updating The Venus International Reference Atmosphere

Abstract

VIRA (The Venus International Reference Atmosphere, ed. by A.J.Kliore, V.I. Moroz, and J.M.Keating) was compiled in 1982–1983 and published in 1985 ( Advances in Space Research, V5, N11). A lot of new data and important findings have appeared over the last decade owing to the experiments on the latest Soviet and US spacecraft and to Earth-based observations. Reanalysis of the previous missions data has also brought some new results. The most essential inputs to the updated VIRA are: 1) new data on the chemical composition (ground based and Galileo observations of the near IR spectra of the Venus nightside emission; VEGA 1, 2 UV in situ spectrometry; Venera 15 infrared spectrometry; reanalysis of Venera 11,13,14 spectrometry; Pioneer Venus entry probes and OIR data), 2) vertical T,P profiles obtained from the VEGA 2 entry probes, IR thermal sounding (Venera 15, Galileo.), and from radio-occultation (Venera 15,16, Pioneer Venus and Magellan Orbiters), horizontal T-profiles from the VEGA 1,2 balloons, 3) winds and turbulence measurements on the balloons, thermal winds retrieved from T-profiles (Venera 15, Galileo); 4) new data on the variability of the cloud structure (Venera 15 IR-spectrometry, VEGA 1,2 entry probes and NIMS observations during the Galileo Venus fly-by).