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Nature of the Venus Clouds as Derived from Their Polarization

Published online by Cambridge University Press:  14 August 2015

James E. Hansen  and
J. W. Hovenier
James E. Hansen
Affiliation:
Goddard Institute for Space Studies, New York, N.Y., U.S.A.
J. W. Hovenier
Affiliation:
Vrije Universiteit, Amsterdam, The Netherlands

Abstract

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The linear polarization of sunlight reflected by Venus is analyzed by comparing observations with extensive multiple scattering computations. The analysis establishes that Venus is veiled by a cloud or haze layer of particles which have a narrow size distribution with a mean radius ~ 1 μ. The refractive index of the particles is 1.44 ± 0.015 at γ = 0.55 μ with a small normal dispersion, the refractive index decreasing from the ultraviolet toward the infrared. The particles exist at a high level in the atmosphere, with the optical thickness unity occurring where the pressure is about 50 mb.

The particle properties deduced from the polarization eliminate all but one of the cloud compositions which have been proposed for Venus. A concentrated solution of sulfuric acid (H2SO4–H2O) provides good agreement with the polarization data.

Type
Part II Terrestrial Planets
Information
Symposium - International Astronomical Union , Volume 65: Exploration of the Planetary System , 1974 , pp. 197 - 200
Copyright
Copyright © Reidel 1974 

References

Born, M. and Wolf, E.: 1959, Principles of Optics, Pergamon, London, p. 86.Google Scholar
Coffeen, D. L. and Gehrels, T.: 1969, Astron. J. 74, 433.Google Scholar
Dollfus, A.: 1966, Contribution au Colloque Caltech-JPL sur la lune et les planètes: Venus. JPL Tech. Memo. No. 33–226, 187.Google Scholar
Dollfus, A. and Coffeen, D. L.: 1970, Astron. Astrophys. 8, 251.Google Scholar
Elterman, L., Toolin, R. B., and Essex, J. D.: 1973, Appl. Opt. 12, 330.Google Scholar
Forbes, F. F.: 1971, Astrophys. J. 165, L21.CrossRefGoogle Scholar
Friend, J. P.: 1966, Tellus 18, 465.Google Scholar
Hansen, J. E.: 1971, J. Atmospheric Sci. 28, 120.2.0.CO;2>CrossRefGoogle Scholar
Hansen, J. E. and Arking, A.: 1971, Science 171, 669.Google Scholar
Hansen, J. E. and Hovenier, J. W.: 1971, J. Quant. Spectrosc. Radiat. Transfer 11, 809.CrossRefGoogle Scholar
Horak, H. G.: 1950, Astrophys. J. 112, 445.Google Scholar
Hovenier, J. W.: 1971, Astron. Astrophys. 13, 7.Google Scholar
Hunten, D. M.: 1971, Space Sci. Rev. 12, 539.Google Scholar
Kuiper, G. P.: 1957, in Zelikoff, M. (ed.), Threshold of Space, Pergamon, New York, p. 78.Google Scholar
Lazrus, A. L., Gandrud, B., and Cadle, R. D.: 1971, J. Geophys. Res. 76, 8083.Google Scholar
Lyot, B.: 1929, Ann. Obs. Paris (Meudon) 8, [available in English as NASA TT F-187, 1964].Google Scholar
Marin, M.: 1965, Rev. Optique 44, 115.Google Scholar
Mossop, S. C.: 1965, Geochim. Cosmochim. Acta 29, 201.Google Scholar
Rosen, J. M.: 1971, J. Appl. Meteorol. 10, 1044.2.0.CO;2>CrossRefGoogle Scholar
Sill, G. T.: 1972, Comm. Lunar Planet. Lab., No. 171, 191–198.Google Scholar
Veverka, J.: 1971, Icarus 14, 282.Google Scholar
Young, A. T.: 1973, Icarus 18, 564.CrossRefGoogle Scholar