Summary of preliminary results of the Venera 13 and Venera 14 missions.

Attention is given to preliminary results concerning the parameters of the Venera 13 and 14 landing sites, including atmospheric, aerosol and surface materials compositions, solar UV energy absorption, electrical discharges, and methods for imaging the Venus surface's features. Descriptions are given of the design features and performance capabilities of such Venera instruments as the mass spectrometer, gas chromatograph, humidity sensor, and spectrophotometer. Venera 13 and 14, for the first time, have included an experiment for the determination of rock compositions which detected the fluorescent X-ray emission of the soil by means of four proportional gas counters. At the Venera 13 site, soil composition is similar to a terrestrial leucitic basalt having a high potassium content.