Target Acquisition Reference Information . ... In almost all cases where an onboard acquisition will not work (because the object is in a crowded field, or is variable, or is a moving target), it is sufficient to use an early acquisition to get a WFPC2 or FOC image a few weeks in advance of the GHRS observation. ... Explicit BRIGHT and FAINT limits may be specified if you desire, although there is an increased risk of a failed acquisition unless you are confident of those fluxes. ... MAPs . ...

Atmospheric influence on the different radio-engineering system functioning . ESTIMATION OF ATMOSPHERIC OPTICAL CHARACTERISTICS AND REMOTELY SANSED IMAGE CORRECTION . ... Direct transmittance estimation results for 12 channels of the spectrometer CHRIS. ... We have managed to develop a direct method of estimating the discrete Normalized Atmospheric Point Spread Function (NAPSF) from available images alone, not using any external sources of information about the atmosphere. ... IRE RAS 1996-20 11 ...

THE THERMAL RADIATION OF THE LUNAR SURFACE IN THE IR RANGE OF THE SPECTRUM (10-12 µm). ... 0.80 0.60 0.40 0.20 0.00 -0.20 -0.40 -0.60 -0.80 -0.80 -0.60 -0.40 -0.20 0.00 0.20 0.40 0.60 0.80 Fig.1 0.80 0.60 0.40 0.20 0.00 -0.20 -0.40 -0.60 -0.80 -0.80 -0.60 -0.40 -0.20 0.00 0.20 0.40 0.60 0.80 Fig.2 0.60 0.40 0.20 -0.00 -0.20 -0.40 -0.60 -0.60 -0.40 -0.20 -0.00 0.20 0.40 0.60 0.80 Fig.3 Indicatrix of the thermal radiation of the Moon (10.5-12.5 µ). ...

... Star formation requires interstellar clouds that are cold and dense enough for self-gravity to overcome internal pressure from gas thermal motions and other factors, thus leading to cloud contraction and eventual collapse to stellar densities. ... Absorption has all of these parameters plus one more describing the fraction of the emission (p) that is behind the absorbing cloud. ... Obser ving Interstellar Hydrogen Clouds Clouds in the ISM can produce either emission or absorption spectra. ...

In this gallery are many images of Low Surface Brightness Galaxies which have recently been discovered and analyzed. ... The central surface brightness of this galaxy is 24.28 . Malin 2 This galaxy is another huge disk galaxy with a scale length of 15 kpc and a redshift of 15000 km/a. The high surface brightness knot in one of its spiral arms actually has the same color, luminosity and H-alpha equivalent width as the entire Large Magellanic Cloud . ... Truly it is a Low Surface Brightness Galaxy. ...

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. ...

The parameter brief (with its actual uncertainty sbrief) is the mean effective surface brightness in B-band , i.e. the mean surface brightness inside the effective aperture (the circular aperture enclosing one-half the total flux). It is expressed in mag arcsec -2 . ... 2) from the mean surface brightness "LV" inside the effective isophote (elliptical isophote enclosing one half the total flux) measured by Launberts&Valentijn (1989) . ... Effective radius . ... HyperLeda . ...

... The visibility datasets possibly contain correlations for different polarizations and Stokes parameters. There are two basic ways that polarization characteristics can be measured: firstly, two orthogonal feeds can be present on the antennas, and the four different polarization correlations from a baseline can be taken and recorded. ... There are two ways the user can determine which polarizations he or she wants to process, either with the select parameter, or with the stokes parameter. ...

... Colours of stars and galaxies hold information on intrinsic and extrinsic parameters, such as stellar temperatures and galaxy populations, selective absorption and colour changes due different dust contents and inclination angles of galaxies, as well as galaxy redshifts and evolution. ... The colour magnitude diagram of 65000 galaxies to which all above-mentioned quantities and others contribute can only be explained by comparison with simulations. ... Colours are also of technical help. ...

... Archives . ... ArXiv] 4th week, Oct. 2007 . ... In search of an unbiased temperature estimator for statistically poor X-ray spectra . ... I was very excited because I haven?t seen any astronomical papers discussing unbiased estimators solely. By the same token that the authors discussed bias in the о‡^2 method and the maximum likelihood estimator, we know that the о‡^2 function is not always symmetric for applying н”о‡^2 =1 for a 68% confidence interval. ... Chandra Blog . ...

... real . ... All sources with MASKFRAC mfraclimit will have flag 1 set to T (see description). brcolumn . ... Name of column to be used to define a circle of influence of a bright source (used to set flags 2 and 4) . ... Number by which the 'brcolumn' is multiplied to obtain the 'circle of influence' radius in arcs (for flag 2) . ... Number by which the column EXT is multiplied to obtain the 'circle of extended emission' radius in pixels (internally converted to arcs) (for flag 3 and 5) . ...

... The Irkutsk IS radar has the opportinuty to measure several ionospheric plasma parameters such as electron density N e , electron and ion temperatures T e , T i , and drift plasma velocity along the sounding direction. ... To the 1999-2001 data we have added the E-layer ionosphere model to electron concentration profile, which has been constructed by integral concentration from the ionosphere beginning from 160 km obtained from experiment. ... Capabilities and samples | ...

ALMA | ... Phase Correction Algorithms | ... On this page, we describe what the phase correction algorithms set out to do and the framework we have developed to optimally use all of the available information. ... We are developing a Bayesian framework to combine all the information we have about the current and future meterological conditions (which are naturally accommodated as priors in a Bayesian scheme) with detailed physical models of the atmosphere. ...

... Guider functions . ... Guide Sensor Performance . ... Guide Sensor Sky Coverage/ Star Availability . Guide Star Selection Criteria . ... Guide fiber organization and reach at plug plate . ... Plug plate holes for guide stars are identical to those for science FO . ... FOV for each of 9 guide stars is 7.4 arcsec dia. (0.45 mm FO, Sumitomo IGN-05/10) . ... Selected guide stars must have no neighbor stars within TBD (5 arcsec) radius that have a brightness within TBD (5 mag.) of guide stars . ...

Links given for particles of different shapes allows one to access our graphics illustrating the dependence of various optical properties of model scatterers on their parameters. ... Q ext , Q sca , Q abs , Q bk , albedo, g, Q pr vs x for different m . F ij vs theta for different x, m . ... Q ext , Q sca , Q abs , Q bk , albedo, g, F ij vs x for different m, alpha . F ij vs theta for different x, m, alpha . ... Q ext , Q sca , Q abs , Q bk , albedo, g, Q pr vs x for different m (TE/TM modes) . ...

... 18-Jan-2010 17:22 . ... Apache/2.2.3 (CentOS) Server at www.wdcb.ru Port 80 ...

Next: Radial velocity of the Up: Optical spectrum of IRAS04296 Previous: Observations and spectra reduction . ... However, molecular emission features are only very rarely observed in the optical spectra of PPNe. ... On the other hand, it is well known that cometary nuclei spectra show prominent Swan band emission. In both spectra of IRAS04296 we have discovered strong emission in the (0;0) and (0;1) bands of the Swan system of the molecule. ... Now consider the case of IRAS04296. ...

... Using the uvby -photometry and proper motion data for about 5500 F stars within 80 pc from the Sun, we have studied velocity ellipsoid parameters and obtained the following results. 1) The sizw of all wllipsoid semiaxes increase systematically for groups of stars with the decrease of both temperature (at constant metallicity) and metallicity (at constant temperature). ... As a result, each of the three parameters - temperature, metallicity and velocity dispersion - is an age indicator. ...

Next: A New IRAF Catalog Access Tool for Astrometry . Up: Iraf Packages . ... Twofitlines is a tool developed within IRAF, optimized to be used with data containing multiple spectra along the spatial axis of the detector. A given spectral feature can be decomposed in one or several Gaussian components. ... A given spectral feature can be modeled using one or more components (currently only Gaussian profiles are available), . ... Close spectral features could be modeled simultaneously. ...

... Contacts . 2012: . ... We refined the fundamental parameters of the components, the orbital periods, and the conditions of photospheric heating of the secondary component by the ultraviolet radiation of the hot component. ... The observations of the star clusters associated with ultra-luminous x-ray sources (ULXs) in four galaxies on the 6-meter and VLT telescopes have shown that all the ULXs are located within 200pc of very young star clusters (younger than 5 million years). ... Archive . ...