Sky temperature map of the cosmic microwave background (CMB) is one of the premier probes of cosmology. To minimize instrumentally induced systematic errors, CMB anisotropy experiments measure temperature differences across the sky using paires of horn antennas with a fixed separation angle, temperature maps are recovered from temperature differences obtained in sky survey through a map-making ...

A Sun-tracking imaging system is implemented for minimizing circumsolar image distortion for improved short-term solar irradiance forecasts. This sky-imaging system consists of a fisheye digital camera mounted on an automatic solar tracker that follows the diurnal pattern of the Sun. The Sun is located at the geometric center of the sky images where the fisheye distortion is minimized. Images f...

Many animals, including insects, are able to use celestial cues as a reference for spatial orientation and long-distance navigation [1]. In addition to direct sunlight, the chromatic gradient of the sky and its polarization pattern are suited to serve as orientation cues [2-5]. Atmospheric scattering of sunlight causes a regular pattern of E vectors in the sky, which are arranged along concentr...

Various spherical radiative transfer (SRT) computer codes that model ultraviolet (UV) sky intensities incident at the Earth’s surface are compared for clear-sky (Rayleigh scattering and ozone absorption) and hazy-sky (stratospheric volcanic aerosol, Rayleigh scattering, and ozone absorption) atmospheric conditions. Calculated sky intensities using Dave vector (pseudospherical), Dave scalar (pse...