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Mode decoupling during retrorefraction as an explanation for bizarre radar echoes from icy moons

Nature volume 319, pages 755–757 (1986)Cite this article

Abstract

Radar echoes from Europa, Ganymede and Callisto, large ice-covered moons of Jupiter, have characteristics that differ markedly from those of other natural targets1–3. A decoupling of two characteristic modes of propagation appears to be the key to an understanding of the anomalous distribution of power among the polarized components of the echoes. Such decoupling is inherent in the double-reflection theory of Ostro and Pettengill4 and the subsurface scattering model of Goldstein and Green2. However, neither of these theories explains the astounding strengths of the echoes as well as the retrorefraction peak in the refraction scattering model of Hagfors et al.5, which in turn is less able to represent the power distribution. The two concepts of mode decoupling and retrorefraction are combined here to explain the strength, distribution and other features of the echoes. Causes of the decoupling are proposed and their morphological implications are introduced.

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References

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Authors and Affiliations

  1. Center for Radar Astronomy, Stanford University, Stanford, California, 94305, USA

    Von R. Eshleman

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  1. Von R. Eshleman
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Eshleman, V. Mode decoupling during retrorefraction as an explanation for bizarre radar echoes from icy moons. Nature 319, 755–757 (1986). https://doi.org/10.1038/319755a0

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