Crepuscular and solar rays are visible by means of the contrast between sunlit and (usually) cloud-shaded portions of the atmosphere. Their visibility depends on (1) the volume angular-scattering coefficient (), (2) the brightness of the sunlit sky, and (3) the integrated optical path through the shadowed regions of the atmosphere. We show that the geometry of path length through the umbra (3) ...

[1] This study simulates the direct radiative forcing of organic aerosol using the GFDL AM2 GCM. The aerosol climatology is provided by the MOZART chemical transport model (CTM). The approach to calculating aerosol optical properties explicitly considers relative humidity–dependent hygroscopic growth by employing a functional group– based thermodynamic model, and makes use of the size distribut...

We calculate photometric redshifts from the Sloan Digital Sky Survey Main Galaxy Sample, The Galaxy Evolution Explorer All Sky Survey, and The Two Micron All Sky Survey using two new training–set methods. We utilize the broadband photometry from the three surveys alongside Sloan Digital Sky Survey measures of photometric quality and galaxy morphology. Our first training–set method draws from th...

I present a new algorithm, Curved-sky grAvitational Lensing for Cosmological Light conE simulatioNS (CALCLENS), for efficiently computing weak gravitational lensing shear signals from large N-body light cone simulations over a curved sky. This new algorithm properly accounts for the sky curvature and boundary conditions, is able to produce redshift-dependent shear signals including corrections ...

Conventional method to identify and classify individual chromosomes depends on the unique banding pattern of each chromosome in a specific species being analyzed (1, 2). This classical banding technique, however, is not reliable in identifying complex chromosomal aberrations such as those associated with cancer. To overcome the limitations of the banding technique, Spectral Karyotyping (SKY) is...

In the rendering of outdoor scenes in virtual environments, the sun's position, sky color, clouds, shadow, trees, grass etc play very important roles in making it realistic. In this paper Sky color and the sun’s position are combined. Specific longitude, latitude, date and time are required parameters to calculate the exact position of the sun. The sun's position is calculated based on Julian d...

We have completed a robotic wide-angle imaging survey of the southern sky (δ = +15 to −90) at 656.3 nm wavelength, the Hα emission line of hydrogen. Each image of the resulting Southern H-Alpha Sky Survey Atlas (SHASSA) covers an area of the sky 13 square at an angular resolution of approximately 0.8 arcminute, and reaches a sensitivity level of 2 rayleigh (1.2 × 10 erg cm s arcsec) per pixel, ...

The diffuse sky emission in 7 spectral bands between 2 and 4.6 microns has been observed with a cooled balloonborne IR telescope (TRIP). The results, reported here, confirm state-of-the-art atmospheric models for the continuum emission at λ > 3μm and for the OH component at λ < 2.3μm. On the other hand, excess flux in the 2.3 to 2.5μmatmospheric window is found at a level of λIλ ' 1.5− 2 10−10 ...

In the sky, tiny particles are needed for clouds to form. These particles can come directly from the ground (for example, from volcanoes or pollution released by industry) or they can form in the sky when sticky molecules clump together. More particles in the sky make clouds whiter. Whiter clouds reflect more of the sun’s rays. This tends to cool down Earth’s climate. So particles in the sky af...

Orbital detectors without pointing capability have to keep their field of view axis laying on their orbital plane, to observe the largest sky fraction. A general approach to estimate the exposure of each sky element for such detectors is a valuable tool in the R&D phase of a project, when the detector characteristics are still to be fixed. An analytical method to estimate the sky exposure is de...