Computer models of objects (galaxies, circumstellar disks, etc.) are often generated to compare with observed images. ... When comparing models to WFPC2 images, it is often forgotten that the instrumental PSF can have a very significant effect. ... Also, the undersampling of the WFPC2 cameras makes the model image very sensitive to subpixel alignment. ... Left) WFPC2 WFC F814W image of HH30 (0.1 arcsec/pixel); (Middle) Model of HH30 disk; (Right) Model of HH30 disk convolved with a Tiny Tim model PSF. ...

... ATNF Home . ... 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) . ... Australia Telescope 20GHz Survey . ... Visiting Parkes radio telescope . ... Parkes radio telescope webcam . ... Probing ISM Models with H observations . ... Turbulent Models of the ISM . ...

ASC-FITS-2.0.1: ASC FITS File Designers' Guide (Rots and McDowell) (1999 Jun) . ASC-FITS-REGION-1.0: FITS region document (McDowell and Rots) (1998 Mar) . ... CXC-DM-001 Introduction: Data Analysis with the Chandra Data Model (2001 Oct) . ... 1998 Feb 26: SDS-1.0: Data Product List: obsolete . ... 1998 Mar 09: SDS-10.0: (ASC-FITS-REGION-1.0) FITS region document: see ASC-FITS-REGION-1.0 . 1998 Feb 09: SDS-11.0: FITS function document (superseded by ASC-FITS-FUNCTION-1.2) . ...

... If you elect to model the sky, you will see some graphs showing the progress of the fitting procedure. First, if some bright stars were observed, you see a plot of sky data (for a given band and night) as a function of the adjacent star's brightness. ... Second, if there are enough dark-sky data to model, you will see a plot of the dark-sky data (corrected for star light) as a function of airmass, with the fitted term drawn in as + signs. ... Again, the fit is shown with + signs. ...

ON THE IMPACT OF THE GALACTIC ABERRATION ON VLBI-DERIVED PRECESSION MODEL Z.M. MALKIN Pulkovo Observatory Pulkovskoe Ch. ... Corrections to adopted precession rate are usually computed from the linear trends in long-term time series of celestial pole offset (CPO), which are the differences between the measured and the theoretical coordinates of the celestial pole. ... CONCLUSIONS We have estimated the impact of GA on parameters of precession-nutation model derived from VLBI observations. ...

... The magnetic field of the Earth has been investigated by satellites for several decades now, and enough of it is known to model its average strength and shape during different levels of overall magnetic activity. Presently the most used empirical global magnetic field models are the Tsyganenko models (1987, 1989) , referred to as T87 and T89, respectively, although even these consist of several submodels. ... Earth's magnetic field from T89c model during Kp=2 for different seasons. ... Res. ...

... Lightcurves of two satellites of Saturn, namely Hyperion (S7) and Phoebe (S9), were modeled using algorithms and programs developed for calculat­ ing the rotational dynamics and constructing theoretical lightcurves of planetary satellites. ... The problem of fitting an observed lightcurve with the model one is solved by varying the initial data and values of the parameters of the problem. ... The value of the MLCE calculated for the deduced initial data and values of the parameters is close to zero....

Next: The ESO VLT CCD Detectors Software . ... Up: Instrument-Specific Software . ... The framework for data calibration and analysis of the VLT instrumentation is presented, based on the concepts of a calibration plan, pipeline calibration, quality control, and archiving of calibrated data for a ground-based observatory. ... Quality Control Pipeline provides quality assessment for instrument performance data and observing conditions, and tests the results of the Reduction Pipeline. ...

Next: MASSES Up: EXTREME HELIUM STARS: PULSATION Previous: STELLAR PROPERTIES . ... Following main-sequence evolution, a red giant star in a close binary system may expand to fill its Roche lobe. ... Although Iben & Tutukov (1984) used this model to account for the EHes, the latter are not binaries (Jeffery et al. ... Final helium-shell flash in a post-AGB star. ... Accretion from the disk onto the surviving WD creates a star with a degenerate CO core and a helium envelope. ... Other models. ...

... Abstract: We present an extensive study of the radiative transfer in dusty galaxies based on Monte Carlo simulations. ... We have explored the dependence of A_l on a conspicuous set of quantities (Hubble type, inclination, dust optical thickness, dust distribution and extinction properties) for a large wavelength interval, ranging from 1250A to the K band, thus finally providing a comprehensive atlas of dust extinction in galaxies, which is electronically available. ... S04_MD20[ att , abs ] . ...

... Science Activities > PhD Thesis Topics offered by ESO Faculty Members > Thesis Topic: Dynamical models of multiple globular cluster populations around massive galaxies . ... Different techniques have been devised to separate multiple GC populations and perform dynamical analyses. ... Within this project, the PhD candidate will examine mock models of multiple GC populations around massive galaxies, devising `blinded' functional tests and comparing the possible sources of bias in different techniques....

... Astronomy for Kids . ... Astronomy 101 . ... Astronomy Day . ... Astronomy and astrophysics rely heavily on computer modeling, but being neither a physicist nor computer scientist, I cannot relate to the term "computer model." What is such a model, and how do scientists build one? ... Get instant access to subscriber content on Astronomy.com! ... If you are already registered on Astronomy.com, please log in below. ... Finescale Modeler | ... Model Railroader | Model Railroader Video Plus | ...

... The resulting spectra were analyzed with a kinematic Monte Carlo model which allows estimation of the OH production rate, neutral gas outflow velocity, and distribution of the out-gassing from the nucleus. ... The best-fit model spectrum is shown together with the observed line. ... Both models are scaled to match the average off spectrum. When the same scaling is applied to the nucleus-centered model spectra, shown on the right, it is clear that only the quenched model matches the observations. ...

Cost Estimating Web Site . ... 2005 NASA Cost Analysis Symposium Databases . ... World , European Communities , Other European Countries , Americas , Asia , Africa , General US , US Federal Government , US Department of Defense , Aerospace Industry , NASA , Science & Engineering Handbooks . NASA Cost Estimating Handbook 2004 , Parametric Estimating Handbook .. ... Consumer Price Index , Employment Cost Index , GDP Deflator , Import Price Index , NASA New Start Index , Producer Price Index . ...

STEP INTO THE BLUE - MEADE INSTRUMENTS PRODUCT GUIDE . ... Telescopes . LX850 Series . ... LX600 Series . ... Superb optical performance coupled with time proven computerized pointing and tracking has made the LX200 ACF series a best-seller in the high-performance telescope class. LX90 Series . MeadeтАЩs LX90 ACF is a favorite of astronomers making the jump to their first, serious, larger aperture telescope. ... Coronado Accessories . ... LX90 GPS Module (8" models) . ... LX90 GPS Module. ...

... 2.3 Establishing the Extragalactic Distance Scale . ... 2.3.2 The Second Rung: Distances to stellar clusters . ... 2.3.4 Distances to Local Group Galaxies . ... The Luminosity Function of Planetary Nebulae . ... 3.2.2 Clusters of Galaxies . ... 4.2 Evidence for Dark Matter as a Function of Scale Size . ... 4.3 Other Dark Matter Indicators for Galaxies . ... What is the nature of the large-scale distribution of matter in the universe as traced by the three-dimensional galaxy distribution? ...

... The most powerful and widely used methods to calculate the scattering matrix of a fractal cluster are based on the coupled dipoles methods (e.g. the Discrete Dipole Approximation, DDA) and the theory of light scattering by a cluster of spherical particles [2-4]. ... At present the procedure of calculation of the scattering matrix is well developed for both an oriented cluster of spherical particles and for chaotically oriented clusters of such particles [4]. ...

XMM-Newton Science Analysis System Page: 1 rgsbkgmodel July 2, 2008 Abstract Compute a model background spectrum from RGS background templates 1 Instruments/Modes Instrument Mode RGS Spectroscopy 2 Use In the interactive environment. pipeline processing no interactive analysis yes 3 Description The aim of this package is to compute a model spectrum of the RGS background applicable to a given observation from a combination of observations of empty elds. ... Model background spectra (OGIP-compliant). ...

... Bojan Nikolic web pages (r. 329) . ALMA . ... AATM is a re-packaging of the version of ATM as used by the ALMA online calibration software ?TelCal?. ... The main reason for AATM is to bring the version of ATM used by ALMA to an as wide an audience as possible. ... This version of AATM therefore corresponds exactly to version on ATM-0_3_0 branch of the CVS, and will (I believe) be the same as what is used in ALMA 7.1. ... Computing dispersive atmospheric delay with AATM . ... ATM and AATM . ...

... We find a transition of LBV star from the LBV instability strip to the region of classical WN for the first time. ... Numerical modeling of the atmospheres of these objects are very important for understanding the evolutionary relationship WR and LBV stars, as well as of the physical causes of LBVs variability. We studied spectra of two very luminous stars in the M33 galaxy - LBV V532 and late WN star FSZ35. ... Bottom: The spectrum of FSZ35 with the final model . ...