The standard model procedure employed for the determination of asteroid photometric properties from single-wavelength infrared flux-density measurements has long been suggested for use with single-wavelength microwave flux-density measurements. Microwave observers, however, have usually assumed that the radio continuum spectra of the asteroids should closely follow a rapidly rotating blackbody ...

The results of a new multispectral infrared retrieval scheme for obtaining fractional cloud cover and 11-/am emissivity are compared with those of the spatial coherence method which obtains fractional cloud cover assuming that the clouds are opaque at infrared wavelengths. Both methods are applied to 4-km NOAA advanced very high resolution radiometer global area coverage data for 250-km-scale r...

Using far-infrared emission maps taken by IRAS and Spitzer and a near-infrared extinction map derived from 2MASS data, we have made dust temperature and column density maps of the Perseus molecular cloud. We show that the emission from transiently heated very small grains (VSGs) and the big grain dust emissivity vary as a function of extinction and dust temperature, with higher dust emissivitie...

Radiometers are adept at retrieving near surface ocean wind vectors. The Naval Research Laboratory (NRL) launched the WindSat polarimetric radiometer with five frequency channels to observe the sea surface and test its ability to accurately measure the wind in various weather conditions. This study focuses on its performance in extreme conditions – the high wind and heavy precipitation of a tro...

Detecting and identifying weak gaseous plumes using thermal imaging data is complicated by many factors. These include variability due to atmosphere, ground and plume temperature, and background clutter. This paper presents an analysis of one formulation of the physics-based radiance model, which describes at-sensor observed radiance. The background emissivity and plume/ground temperatures are ...

Observations from satellite microwave instruments have a large information content and are known to improve the quality of global analyses of the atmosphere. However, the use of these observations remains far from being optimal. Indeed, only microwave observations, for which the surface contribute the least, are currently assimilated. This restriction is mainly due to remaining uncertainties ab...

Cosmic dust is pervasive within our galaxy and it is reasonable to suspect it is dispersed in various ways throughout the universe. Cosmic dust has emissivity when exposed to electromagnetic energy sources. The emissivity of cosmic dust contributes to cosmic radio noise and concentrations of it alters electromagnetic waves by refraction. Cosmic dust is concentrated in our Sun’s heliosphere and ...

The potential of passive microwave radiometry for the soil moisture measurement is a well established one, especially in the long wave length regions due to its high penetrating capacity through vegetation. Radiometric data can be used as a mapping tool for classifying the crops, examining their health and viability and monitoring the farming practices. The radiometric data or the emission of m...

We calculate the reionization history in Cold Dark Matter (CDM) models. The epoch of the end of reionization and the Thomson scattering optical depth to the cosmic microwave background depend on the power spectrum amplitude on small scales and on the ionizing photon emissivity per unit mass in collapsed halos. We calibrate the emissivity to reproduce the measured ionizing background intensity a...