The polarization of electromagnetic radiation reflected by a particulate surface is determined by a four by four reflection matrix. Symmetry relations are quite common for such reflection matrices. The reciprocity and mirror symmetry relations are combined to derive a third symmetry relation. These three relations are used to simplify reflection matrices for a variety of special directions of i...

This paper summarizes our present, preencounter understanding of the physical and chemical processes controling the inner (r < 1000 km) region of cometary atmospheres. Special emphasis was attached to compiling a self-consistent set of governing equations. We are aiming this review at readers who want to understand the present status of the mantle and coma regions and/or who want to develop new...

SUMMARY Temperature measurements, using the SLR method, are presented for the expansion of nitrogen in nozzles attached to a shock-tube. The measurements were made at an area ratio of 8.5 in a two-dimensional nozzle and at an area ratio of 152 in a conical nozzle. Initial conditions were such that at the entrance to the nozzles the temperature ranged between about 2500 K and 5300 K and the pres...

Motivated by recent 3-D calculations of the explosion of Type Ia supernova via a pure deflagration we calculate the observed spectra at 15–25 days past maximum light of a parameterized model which has a considerable fraction of unburnt C+O in the central regions. Rather than attempting a self consistent 3-D calculation, which is beyond the scope of current computer codes, we modify the composit...

This is the second part of the validation effort of the recently developed vector version of the 6S (Second Simulation of a Satellite Signal in the Solar Spectrum) radiative transfer code (6SV1), primarily used for the calculation of look-up tables in the Moderate Resolution Imaging Spectroradiometer (MODIS) atmospheric correction algorithm. The 6SV1 code was tested against a Monte Carlo code a...

Transiting planets have greatly expanded and diversified the exoplanet field. These planets provide greater access to characterization of exoplanet atmospheres and structure. The Kepler mission has been particularly successful in expanding the exoplanet inventory, even to planets smaller than the Earth. The orbital period sensitivity of the Kepler data is now extending into the Habitable Zones ...

Planetary nebulae (PNe) are very important kinematical tracers of the outer regions of early-type galaxies, where the integrated light techniques fail. Under ad hoc assumptions, they allow measurements of rotation velocity and velocity dispersion profile from descrete radial velocity fields. We present the results on the precision allowed by different set of radial velocity samples, discuss the...

The application of ionic processes to the purification of manned space-cabin atmospheres was investigated in anticipation of a need for a radically new atmospheric purification system for some of the presently scheduled space jaurneys. Processes considered are (1) ion-molecule reactions of contaminant mulecules with specific added molecule ions (O0, 0) and (2) clustering of contaminant molecule...

The concept of network returnability is reformulated as an equilibrium constant for a reaction network. Using this concept we study the atmospheric reaction networks of Earth, Mars, Venus and Titan. We found that the reaction network in the Earth’s atmosphere has the largest disequilibrium, followed by that of Titan which is still far from the most returnable atmospheres of Mars and Venus. We f...

The effects of different modified atmospheres (air: atm1; 100% CO2: atm2; 100% N2: atm3; 50% CO2/50% N2: atm4) on the textural and sensory characteristics of the ready-to-serve pizza at 7 ̊C ± 1 ̊C were investigated. The values of hardness, gumminess and chewiness were found to be increased during the storage period while cohesiveness and springiness exhibited a decreasing trend. Overall, the 100...