Chemistry of Small Components of Upper Shells of Venus

Lunar and Planetary Science XXIX 1003.pdf

CHEMISTRY OF SMALL COMPONENTS OF UPPER SHELLS OF VENUS. B.M. Andreichikov, Space Research Institute, Russian Academy of Sciences, 117810, Profsojuznaja st. 84/32,Moscow, Russia.

Received by means of the VEGA 1, VEGA 2, a water mass (~ 4,5 ´ 1022 g, in the manner of GALILEO spacecrafts, information on Venus [1– hydro-xylgroups). 9] has vastly increased our knowledge about this (5) The possibility of presence in atmosphere of planet, but has introduced new questions connected planet of oxidizes of phosphorus is shown. (6) It with the chemistry of the atmosphere, the surface, had been revealed that they form of the atmos- and interaction processes. Additionally last publi- pheric components mixing ratio vertical profiles cations of the data of the optical spectroscopy [9– participating actively in reactions of the oxidation- 13] have revealed else greater divergence of them reduction. (7) The possibility of formation at a rate with results of the gas chromatography [14–17], of of 11–12 km of traces of aerosol of the layered the mass- spectrometers [18] and of the others of polymers (P2O5)n is shown. (8) It was revealed, that the contact measurements methods [6]. It had been seeming discord of results of direct measurements reported in works [7,8] about finding in the Ve- in the atmosphere of Venus is connected with the nusian night clouds of aerosol which contain a difference of chemical processes daytime and in the phosphor. The nephelometeric measurements [19] night, stipulated by the influence (of deeper at a have shown also that lower, the most dense clouds day time) of photochemical reactions products in layer an (47,5–50,5 km) is formed in the night and the upper troposphere. (9) Night vertical profile is absent daytime. So far as the aerosol which con- xH2O concordant with results of direct measure- tain phosphor is revealed, basically, in the lower ments in atmosphere [20, 6] is calculated. (10) layers of the clouds , the most probable genesis its Night vertical profiles xSO2, xH2S and day vertical is a condensation from the vapors which are prod- profiles xSO2, xH2S concordant with results of direct uct of processes of the atmosphere interaction with measurements in atmosphere [11, 15, 17] are cal- surface of planet. This bring about thoughts about culated. (11) Vertical profiles xco, xcos , xs concor- the active participation of phosphorus in shaping of dant with results of direct measurements in atmos- the upper shells of planet (of surface, of atmosphere [13,14,16–18,21,23] are calculated. (12) A phere). possibility of formation above 42 km in the night In this work is conducted thermodynamic and impossibility - daytime (near a noon) of the analysis of system a surface—atmosphere (till the aerosol which contain phosphor is motivated. (13) height 42 km) planets with the calculation of fly- A probability of the condensation in the night ing, in conditions of Venus, of phosphorus oxides. above 42 km of sulfur is shown. Following results were received. (1) It is shown that atmosphere and surface of Venus, as well as components of atmosphere between itself inhere in the conditions of the thermodynamic equilibrium. (2) As a result of the thermodynamic analysis of the system a surface - atmosphere were calculated the concentrations of the atmospheric components near surface of planet which correspond with the measurements data (SO2 [11], H2O [20], S[21]). -5 -5 - H2O - 6,5 ´ 10 , SO2 - 2,0´ 10 , P4O10 - 2,3´ 10 5 -5 -5 - , CO - 1,28´ 10 , COS - 1,2´ 10 , H2 S - 3,3´ 10 6 -6 -7 -9 , HCl - 2,3´ 10 , S - 4,1´ 10 , H2 - 6´ 10 , HF - -9 -10 -11 2,2´ 10 , P4 O9 - 5´ 10 , CS2 - 1,55´ 10 , SO - -12 -14 4,1´ 10 , SO3 - 2,45´ 10 . (3) The possibility of existence hydroxylsilicates (stavrolite) in these conditions is revealed. (4) Hypothetical mineral composition of rocks corresponding to the calculated system of the heterogeneous equilibrium and results of direct measurements of the chemical elements contents in the samples of Venus rocks [22], has allowed to estimate by the bound crust of Lunar and Planetary Science XXIX 1003.pdf

CHEMISTRY OF UPPER SHELLS OF VENUS: B. M. Andreichikov

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