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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 pre-upgrade Arecibo imaging, three of the most...
We present high-resolution radio maps of Uranus, made from data collected in 1994 at wavelengths of 2 and 6 cm, which show large-scale changes occurring deep and rapidly in the troposphere. Brightness features in these maps are significantly different from those observed throughout the 1980's. These differences are not due to the changing viewing geometry, but result from atmospheric changes in the...
We present the first images and measurement of flux density of Jupiter at a frequency of 74 MHz, obtained with the Very Large Array in September 1998. We observed simultaneously at frequencies of 74 and 330 MHz. We compare our data with observations taken during the same time at other frequencies (presented by de Pater and 13 others, 2003, Icarus 163, 434-448) and show that the spectrum of Jupiter...
A multi-wavelength radio frequency observation of Venus was performed on April 5, 1996, with the Very Large Array to investigate potential variations in the vertical and horizontal distribution of temperature and the sulfur compounds sulfur dioxide (SO 2 ) and sulfuric acid vapor (H 2 SO 4 (g)) in the atmosphere of the planet. Brightness temperature maps were produced which...
We present observations of Venus at six frequencies: 1.385, 1.465, 4.86, 8.44, 14.94, and 22.46 GHz. These were obtained with the Very Large Array and calibrated in a consistent fashion. The brightness temperature of Venus at the six frequencies is derived and compared to a model which includes the emission from the atmosphere, surface, and subsurface of Venus. A single set of model inputs can fit...
We present new dual circular-polarization radar maps of the western hemisphere of Venus. The results are from a 1993 experiment imaging Venus with 3.5 cm radar. Continuous-wave right circularly polarized flux was transmitted toward Venus from the 70 m Deep Space Network antenna in Goldstone, California. The echo was received in both the same sense (SS) and the opposite sense (OS) of circular polarization...
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