Next: Polarization efficiency: size/shape/orientation effects Up: Optical properties of cosmic Previous: The 2175? feature . To model the interstellar polarization one needs to calculate the forward-transmitted radiation for an ensemble of non-spherical aligned dust grains. ... Let non-polarized stellar radiation passes through a dusty cloud with a homogeneous magnetic field. ... The angle between the line of sight and the magnetic field is ( ). ... where the angle is connected with and ( ). ...

. Next: Spectrum Up: R CORONAE BOREALIS STARS Previous: HISTORICAL BACKGROUND . Figure: The light curve of RCoronae Borealis during a fading event in 1859 . RCB stars were first identified by their characteristic light curves. A part of the light curve of RCrB itself, taken from over a century of observations compiled by Ludendorff (1906) is shown in Figure 1 . Spectrum . Galactic distribution and absolute magnitudes . Numbers and distances . Simon Jeffery . 2002-01-25

... In brief: the frequency-dependent radiative transfer equation is solved for a dust under assumption of spherically-symmetric geometry for its distribution taking into account particle size distribution and quantum heating effects for the very small dust particles. ... Table: Model parameters for IRAS04296+3429. ... parameter . ... hot dust shell) . ... The best fit to the spectral energy distribution of IRAS04296 is shown by heavy solid line (see Table2 for details concerning parameters of the model...

Authors: Yu.G. Shevelev , V.A. Marsakov , . ... We have constructed and investigated properties of metallicity function of disk stars with different ages, proceeding from the statistically restored real altitude distributions of stars at the solar galactocentric distance. It is shown that the metallicity distribution of stars in each age range is not of Gaussian form, but it may be considered as a superposition of two normal distributions centered at -0.2 and 0.0 dex. ...

... Abstract: We present Monte Carlo radiative transfer simulations for spiral galaxies modelled as a stellar disk and a two-phase clumpy dust distribution. ... As a general result, clumpy models are less opaque than the corresponding homogeneous models. ... 0.00 0.15 0.50 0.1 0.5 1.0 2.0 5.0 10.0 0.25 X . ... We have also produced several homogeneous models, to compare to the clumpy models. ... Homogeneous and clumpy models with the same tauV have the same dust mass. ...

... The sample of the Local Volume galaxies (distance smaller than 10 Mpc) gives a unique opportunity to study the properties of galaxies including the weakest objects: the absolute magnitude M B -10 and the virial mass M vir 10 9 M x263C;. ... Luminosity function of the Local Volume galaxies. ... The luminosity functions for galaxies are presented: red dashed line - from the 2dFGRS survey (Norberg et al. 2002); blue dash-dotted line - from the SDSS survey (Blanton et al. ...

... The Science Operation Department is composed of Astronomers, Telescope Instruments Operators(TIOs) and Data Handling Administrators(DHAs). ... Astronomers have proposed several methods to quantitatively measure the amount of turbulence above the telescope, which the most common ones is Differential Image Motion Monitor (DIMM). In optical testing, the Hartmann test is the common method to test the quality of optical components. ... Hartmann mask consists of 48 lenses. ...

http ://hea-www.harvard.edu/ AstroStat /slog/2008/eotw-chisq- distribution / Weaving together Astronomy+Statistics+Computer Science+Engineering+Intrumentation, far beyond the growing borders Fri, 01 Jun 2012 18:47:52 +0000 hourly 1 http ://wordpress.org/?v=3.4 http ://hea-www.harvard.edu/ AstroStat /slog/2008/eotw-chisq- distribution /comment-page-1/#comment-308 Alex Sun, 27 Jul 2008 01:52:08 +0000 http ://hea-www.harvard.edu/ ... Thanks, Aneta, very useful comment. ...

... Empirical and theoretical modeling of 3-D structures in the solar corona is confronted by the tremendous amount of data needed to represent phenomena with a large dynamic range both in size and magnitude, and with a rapid temporal evolution. Octree representation of the 3-D coronal electron distribution offers the right compromise between resolution and size, allowing computation of synthetic images of the solar corona. ... The time interval between images is one day. ...

... It has been largely superceded by MatWeb . Conversion Factors . Material properties . Physical constants . Astronomical constants . This table gives conversion factors to convert various units to their SI equivalents. ... The units are SI. This is a short list of physical constants in SI units. ... Boltzmann constant . ... Gas constant . ... Mass . ... Plank's . ... Radiation constant . ... This is a short list of astronomical constants in SI units. ... Sun . ...

Stellarium 0.12.3 . ... FileљStructure . ... core . ... 233 љ void azimuthalGridDisplayedChanged( const bool ) const ; . 234 љ void azimuthalGridColorChanged( const Vec3f & newColor) const ; . 235 љ void equatorGridDisplayedChanged( const bool displayed) const ; . 236 љ void equatorGridColorChanged( const Vec3f & newColor) const ; . 237 љ void equatorJ2000GridDisplayedChanged( const bool displayed) const ; . 238 љ void equatorJ2000GridColorChanged( const Vec3f & newColor) const ; . ...