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Magellan: Radar performance and data products

G.H. Pettengill·P.G. Ford·W.T.K. Johnson·R.K. Raney·Laurence A. Soderblom
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Abstract

The Magellan Venus orbiter carries only one scientific instrument: a 12.6-centimeter wavelength radar system shared among three data-taking modes. The synthetic-aperture mode images radar echoes from the Venus surface at a resolution of between 120 and 300 meters, depending on spacecraft altitude. In the altimetric mode, relative height measurement accuracies may approach 5 meters, depending on the terrain's roughness, although orbital uncertainties place a floor of about 50 meters on the absolute uncertainty. In areas of extremely rough topography, accuracy is limited by the inherent line-of-sight radar resolution of about 88 meters. The maximum elevation observed to date, corresponding to a planetary radius of 6062 kilometers, lies within Maxwell Mons. When used as a thermal emission radiometer, the system can determine surface emissivities to an absolute accuracy of about 0.02. Mosaicked and archival digital data products will be released in compact disk (CDROM) format.

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G.H. Pettengill, P.G. Ford, W.T.K. Johnson, R.K. Raney, Laurence A. Soderblom. 1991. Magellan: Radar performance and data products. https://doi.org/10.1126/science.252.5003.260

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