Encyclopedia of Planetary Landforms

2015 Edition
| Editors: Henrik Hargitai, Ákos Kereszturi

Radar Anomaly (Venus)

Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-3134-3_289

Definition

A high reflectivity radar feature concentrated in the Venusian highlands.

Category

A type of  radar feature

Description

Strong radar signal reflected from elevations above about 2.5 km (near the equator) or 5 km (at 60°N) on Venus that becomes less pronounced at the highest elevations (Klose et al. 1992); there is also a commensurate low microwave emissivity at the same locations. The planetary average reflectivity on Venus is 0.14 ± 0.03. However, this reflectivity ranges between 0.35 ± 0.04 and 0.43 ± 0.05 in the highlands (Pettengill et al. 1988). Most of the high-altitude regions displaying anomalous reflectivity and emissivity are also very rough on centimeter to meter scales, making inference of surface properties difficult. A notable exception is the crater Cleopatra on the flank of Maxwell Montes, which has enough mirror-like surface elements that a quasi-specular echo could be measured during Magellan bistatic radar experiments in 1994.

Subtypes

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References

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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Arkansas Center for Space and Planetary SciencesUniversity of ArkansasFayettevilleUSA