Planetary brightness temperature measurements at 8.6 mm and 3.1 mm wavelengths

New measurements of the Sun, Moon, Mercury, Venus, Mars, Jupiter, and Saturn at 3.1 and 8.6 mm wavelengths are given. The temperatures reported for the planets at 3.1 mm wavelength are higher than previous measurements in this wavelength range and change the interpretation of some planetary spectra. For Mercury, it is found that the mean brightness temperature is independent of wavelength and that a temperature dependent thermal conductivity is not required to match the observations. In the case of Mars, the spectrum is shown to rise in the millimeter region as simple models predict. For Jupiter, the need to recalculate the spectrum with recent models is demonstrated. The flux density scale proposed by Dent (1972) has been revised according to a more accurate determination of the millimeter brightness temperature of Jupiter.     

Observations and analysis of lunar radio emission at 3.09 mm wavelength

Earth, Moon, and Planets - Observations of lunar radio emission were made at 3.09 mm wavelength (97.1 GHz) from April 18 to May 20, 1971. Absolute brightness temperatures were measured for five...     

Lunar polarization studies at 3.1mm wavelength

Observations of the distribution of linearly polarized lunar thermal emission were made at a wavelength of 3.1 mm with The University of Texas 4.88 m parabolic reflector (0.042° HPBW). A shadow corrected, rough surface, thermal emission model for a homogeneous Moon was leastsquares-fitted to the polarization data. Results indicate an effective lunar dielectric constant of 1.34 ±0.04 with surface roughness characterized by a standard deviation of 17° ± 5° for surface slopes with a normal probability density, independent of lunar phase. A comparison of these results with published values at other wavelengths suggests that the effective lunar dielectric constant, as obtained by lunar emission measurements, decreases with decreasing wavelength of observation. This wavelength dependence may be interpreted in terms of an inhomogeneous surface and/or a surface that possesses intermediate scale surface roughness.This work was supported in part by NASA Grant NGL 44-012-006.