Donald B. Campbell

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Arecibo radar observations of Titan at 13-centimeter wavelength indicate that most of the echo power is in a diffusely scattered component but that a small specular component is present for about 75% of the subearth locations observed. These specular echoes have properties consistent with those expected for areas of liquid hydrocarbons. Knowledge of the(More)
Detailed topographic maps of the lunar poles have been obtained by Earth-based radar interferometry with the 3.5-centimeter wavelength Goldstone Solar System Radar. The interferometer provided maps 300 kilometers by 1000 kilometers of both polar regions at 150-meter spatial resolution and 50-meter height resolution. Using ray tracing, these digital(More)
Shackleton crater at the Moon's south pole has been suggested as a possible site of concentrated deposits of water ice, on the basis of modelling of bi-static radar polarization properties and interpretations of earlier Earth-based radar images. This suggestion, and parallel assumptions about other topographic cold traps, is a significant element in(More)
—Three-dimensional (3-D) maps of the nearside and polar regions of the Moon can be obtained with an Earth-based radar interferometer. This paper describes the theoretical background , experimental setup, and processing techniques for a sequence of observations performed with the Goldstone Solar System Radar in 1997. These data provide radar imagery and(More)
—We describe new 70-cm wavelength radar images of the lunar nearside and limb regions obtained via a synthetic-aperture-radar patch-focusing reduction technique. The data are obtained by transmitting a circularly polarized pulsed waveform from the Arecibo telescope in Puerto Rico and receiving the echo in both senses of circular polarization with the Robert(More)
H-cadherin is a newly characterized cadherin molecule whose expression is decreased in a variety of human carcinoma cells, suggesting that it may play a role in maintaining normal cellular phenotype. To investigate how re-expression of H-cadherin could influence the malignant phenotype of human breast carcinoma cells in vivo, we transfected both control and(More)
Radar imaging results for Mercury's non-polar regions are presented. The dual-polarization, delay-Doppler images were obtained from several years of observations with the upgraded Arecibo S-band (λ12.6-cm) radar telescope. The images are dominated by radar-bright features associated with fresh impact craters. As was found from earlier Goldstone-VLA and(More)
Introduction. One of the major unsolved puzzles about the surface of Venus is the composition and formation process of the radar-bright, low emissivity material that covers much of the high altitude terrain. Maxwell Montes, centered at a latitude of 65 • N, is the tallest structure on Venus with elevations 12 km above the mean planetary radius (MPR) [1]. In(More)