The efficiency of interaction of radiation with a particle and hence its optical properties depend on the particle chemical composition, size, shape, structure, etc. ... Particle size expressed in units of the wavelength of incident radiation, together with chemical composition, most strongly affects the optical properties of a scatterer. ... There are many methods to solve the light-scattering problem for a homogeneous spheroid (our survey of the light-scattering methods see here ). ...

... ratios Evolution Equations with · Now write · Evolution equations now · Define trajectories via Cosmic Trajectories Dust =0 de Sitter phase Radiation =1/3 Initial singularity Cosmic Trajectories · For a range of initial conditions, models re-focus around the flat ... case · For decoupled matter and radiation can solve the equations exactly · Solutions governed by two constants: Non-Euclidean Geometry · Axioms of ...

... Assured of a reliable method of solving the normal equations, we now consider the equations of condition. The observed magnitude m of a star at M air masses with true instrumental magnitude is modelled as ([ 10 ], [ 28 ]) . ... The effective extinction coefficient depends on the effective spectral gradient [ 29 ] of the star, for which we use some color index, affected by half the atmospheric reddening ([ 26 ], [ 10 ]): . ... Thus, for the B band of UBV, we use the (U-V) color. ...

... I tried reducing the field with five different model point-spread functions (PSFs): (1) a spatially invariant PSF derived from ten bright stars in the test image itself; (2) a quadratically varying PSF derived from the NGC 1850 frames discussed by Stetson (1994b); and (3) spatially invariant, (4) quadratically varying, and (5) cubically varying PSFs derived from grids of model profiles generated with Tiny TIM by Shaun M. Hughes. ...

... Research objects and scientific purposes . Space scientific program includes development and launch of two supersmall spacecrafts "Universitetskiy" and "Kompas-2" intended for monitoring of radiation conditions near the Earth. ... All the studies conducted in the near-Earth space are characterised by strong radiation fields. ... The circular polar orbits, which cover all the near-Earth space, are the most favorable for comprehensive studies of the radiation conditions near the Earth. ...

Describes how spatial region boundaries are handled. The golden rule for spatial region filtering was first enunciated by Leon VanSpeybroeck in 1986: . ... With this in mind, the rules for determining whether a boundary image pixel or table row are assigned to a region are defined below. For image filtering, pixels whose center is inside the boundary are included. ... That is, an row is inside the boundary without regard to its integerized pixel value. ...

Next: A Universal Diagram for Up: ``Ecology'' of Magnetic Rotators Previous: The Corotation Radius . The interaction of a magnetic rotator with the surrounding plasma to a large extent depends on the relation between the four characteristic radii: the stopping radius, , the gravitational capture radius,   , the light cylinder radius,   , and the corotation radius,   . ... Hence, the classification of the interaction regimes may well mean the classification of magnetic rotators. ...

On this page you can compute thermodynamics, opacity and nuclear reaction rates for conditions which exist inside the Sun. ... Logarithmic partial derivative dlogP/dlogT (hi_t) . Logarithmic partial derivative dlogP/dlogRHO (hi_rho) . Logarithmic partial derivative dlogP/dlogX (hi_x) . Logarithmic partial derivative dlogU/dlogT (ksi_t) . ... Input field size does not limit the amount of data entered; you can type or paste thousands of lines (10,000 lines tested with output size over 5MB). ...

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... The goal of this course is to teach some basic methodologies for analysing problems of control of partial differential equations. ... When dealing with controllability problems, one has to distinguish between finite-dimensional systems modelled by ordinary differential equations and infinite-dimensional distributed systems described by means of partial differential equations. Most of this course deal with problems related with partial differential equations. ...

Subject, Problems and Objects of Theoretical Astrophysics. ... Stellar Photospheres, Their Features. ... Physics of Continuous Radiation Absorption in Stellar Photospheres. ... Continuous Radiation Absorption in Stellar Photospheres of Various Spectral Classes. Solar Type Photospheres. ... Characterisics of Absorption Lines. ... Interstellar Absorption Lines, Their Features. ... Physical and Dynamic Features of Interstellar Medium, Which Follows from Observations of Interstellar Absorption Lines. ...

Chair of solid state physics . ... The Physics of Phonons . ... In the first part of the course “The Physics of Phonons” the dynamics of atoms in one- and three- dimensional crystalline lattices is considered in detail. The quasiparticle conception in solids, taking phonons as an example, is discussed; creation and annihilation operators of phonons, main properties of acoustic and optical phonons dispersion laws, density of phonon states. ... Crystalline state. ... Acoustic and optical phonons. ...

... ATNF Home . About ATNF . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Australia Telescope User Committee . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . Australia Telescope Compact Array . Mopra radio telescope . ... Australia Telescope Online Archive (ATOA) . ... Parkes | ... Australia Telescope 20GHz Survey . ... Visiting Parkes radio telescope . ... Parkes radio telescope webcam . ... Previous Section: APPENDIX A. The composite . ...

... Observatory tours are usually conducted by the Librarian, who in 2000 showed approximately 500 individuals from 19 different countries around the Observatory. These figures highlight the success of the Armagh Observatory's `open door' policy to attract visits by interested members of the public, groups and societies. ... In addition to tours, the Observatory also organized several public lectures, and hosted a number of special events during 2000. ...

... Science Users Information > Observing with ESO Telescopes > Phase 2 Preparation > Observing conditions . ... Service Mode Philosophy . ... The following definitions of the observing conditions are common between Phase 1 preparation and Phase 2 preparation, as well as between Service Mode and Visitor Mode observations. ... Seeing (Phase 1) and Image quality (Phase2) constraints . ... Please note that observing conditions requested at Phase 2 should match those at Phase 1 (see Service Mode Policies). ...

Crater Gassendi . ... I made this drawing was made on the 26th of november 2001. If you compare this one with the previous drawing of Gassendi (below) the differences are clear. ... This drawing was made on the 28th of september 2001. After nearly a full month without observations I had a one hour gap between the thicker clouds. ... This drawing was made on the 29th of august 2001. ... This drawing was made on the 27th of august 2001. ... This drawing was made on the 25th of august 2001. ...

This page provides explanatory text for the dials shown on the Rice Current Solar Wind Conditions and Current Solar Wind Conditions (Dials Only) webpage. These dials use the last good received set of measurements from the Real Time Solar Wind package on the Advanced Composition Explorer (ACE) spacecraft. ... Measured) This quantity is the number of solar wind protons per unit volume as measured by the ACE Solar Wind Electron Proton Alpha Monitor (SWEPAM) . ... It is measured by ACE/SWEPAM. ...

... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2004 March 25 . An Orion of a Different Color . ... But the striking picture combines images taken through three separate filters, each designed to record different emission lines - light from Sulfur, Oxygen, and Hydrogen atoms glowing in the tenuous nebular gas. ... About APOD | ... NASA Web Site Statements, Warnings, and Disclaimers . ...

... An Orion of a Different Color . ... It is a familiar object though, the grand stellar nursery known as the Orion Nebula . But the striking picture combines images taken through three separate filters, each designed to record different emission lines - light from Sulfur, Oxygen, and Hydrogen atoms glowing in the tenuous nebular gas. At such low densities , Sulfur and Hydrogen atoms emit red colors while Oxygen glows green. ... Publications with keywords: Orion Nebula . ... The Heart Of Orion . ...

... Observing . ... Solar Observing . ... April 3 (SUN) - Solar Observing, Central Park , Manhattan . ... APRIL'S SKY . ... Lecture Series at the American Museum of Natural History The Amateur Astronomers Association is proud to present an astronomy lecture series from October through May each year for our members and the .. ... The€аAmateur Astronomers Association of New York€аwas organized in 1927 to promote the study of Astronomy, emphasizing its cultural and inspirational value. ...