Publication Abstracts
Coffeen and Hansen 1974
Coffeen, D.L., and J.E. Hansen, 1974: Polarization studies of planetary atmospheres. In Planets, Stars and Nebulae Studied with Photopolarimetry, Proceedings of IAU Colloquium 23. T. Gehrels, Ed., University of Arizona Press, pp. 518-581, doi:10.2307/j.ctt2050vsn.36.
Remote measurements of scattered sunlight can be used for quantitative analysis of planetary atmospheres. For the purpose of determining the nature and distribution of atmospheric particles, the most useful measurements are of the degree of linear polarization as a function of wavelength and phase angle. Such measurements can be used to determine whether aerosols are spherical or nonspherical, and, in the case of spherical particles, to determine the particle refractive index. The linear polarization also yields specific information on the size of any scattering particles; for spherical particles it is often possible to obtain precise measures of the mean particle size and the dispersion of the size distribution. Regardless of the particle shape, it is possible to determine the optical thickness of Rayleigh scatterers above a cloud or haze layer.
Polarimetric observations of planetary atmospheres have increased considerably in the past decade with spectral, spatial, and temporal coverage. At the same time, theoretical techniques have been developed for the exact calculation of polarization for model atmospheres containing spherical particles. A comprehensive study of Venus permitted an accurate derivation of the shape and refractive index of the cloud particles, of the mean radius and dispersion of the particle size distribution, and of the cloud-top pressure. For terrestrial water clouds, polarimetric particle sizing has been demonstrated. For the outer planets, the observations are not as complete, but their number is increasing and will include measurement over a wide range of phase angle from flyby space probes.
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BibTeX Citation
@inbook{co05010b,
author={Coffeen, D. L. and Hansen, J. E.},
editor={Gehrels, T.},
title={Polarization studies of planetary atmospheres},
booktitle={Planets, Stars and Nebulae Studied with Photopolarimetry},
year={1974},
pages={518--581},
publisher={University of Arizona Press},
address={Tucson},
series={Proceedings of IAU Colloquium 23},
doi={10.2307/j.ctt2050vsn.36},
}
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RIS Citation
TY - CHAP ID - co05010b AU - Coffeen, D. L. AU - Hansen, J. E. ED - Gehrels, T. PY - 1974 TI - Polarization studies of planetary atmospheres BT - Planets, Stars and Nebulae Studied with Photopolarimetry T3 - Proceedings of IAU Colloquium 23 SP - 518 EP - 581 DO - 10.2307/j.ctt2050vsn.36 PB - University of Arizona Press CY - Tucson ER -
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