... The operators will be explained as they are used. The general notion to keep in mind is that any combination of these operators results in a 2- D affine coordinate transformation in the TF plane, which may be represented using the homogeneous coordinates often used in computer graphicsfoley. ... S _t_c,f_c = g_t_c,f_c,(_t) | ... We denote a time shift to the position , with an operator that has a multiplicative law of composition : (Table 1). ... Note that these two operators do not commute. ...

Their dependence on the diffraction parameter x for several refractive indeces m=n+k i is given in the following figures: . Parameters . ... n =1.5, 2.5, 3.5; . ... fig . ... Their dependence on the scattering angle theta for several diffraction parameters x and refractive indeces m=n+k i is given in the following figures: . ...

... Up: Data Analysis and Processing Techniques . ... Also, a method for quality control of CCD observations is suggested. ... Everyone who observes a celestial object using a CCD detects moving celestial objects as a ``by product''. ... We hope that our investigations may be useful for near-Earth space control and also for searches of the moving celestial objects through analysis of old and new CCD frames obtained at any amateur or professional astronomical observatory. ...

Once students get the hang of it, they can find and measure the brightness of Delta Cephei in a few minutes. ... of Delta Cephei . ... Oct. ... The following table lists the measurements of Delta Cephei made by one amateur astronomer in autumn 1990. ... 4.0 . ... This activity is a simplified version of one that appeared in Hands-On Astrophysics, a series of activities prepared by the American Association of Variable Star Observers with support from the National Science Foundation. << previous page | ...

... SFIT is a general-purpose code designed to optimize theoretical stellar spectra to an observed spectrum. ... While the programme expects input from "stdio", it is more natural to save commands in a file (eg "sfit_input") and run the code simply by . ... If the spectra to be fitted have a filename "star_spectrum", then the best fit spectrum will be written out, together with the renormalized input spectrum, to a file called "star_spectrum.fit". ... sets up model spectrum grid (and for 2nd star) . ...

... 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. ...

... Satellite data ] . SMIS ] . The program is designed to process the specific AVHRR instrument data for calculation and analysis of temperature fields on the sea surface and upper level of clouds. It performs brightness correction for visible channels with regards to clouds altitude. ... The program features a wide variety of classification algorithms (including two-dimensional histogram analysis) and enables to construct personal procedures for classification. ... Back to SMIS Home Page . ...

... Flight 1) 2) 3) Flight 1) 2) 3) model FM1 has the following parts: LNA MY-18, serial number PN 01-0252, factory number FM1; receiver box KRT-18, serial number PN 17660-01, factory number FM-001; DC-DC converters IVEP1 and IVEP2, factory number 05. model FM2 has the following parts: LNA MY-18, serial number PN 01-0252, factory number FM2; Receiver box KRT-18 serial number PN 17660-01, factory number FM-002; DC-DC converters IVEP1 and IVEP2 factory number 06. ... See Appendix 1. ... 2003. ... 2004 . ...

... Tonight's Sky . ... The Magazine . ... Observing . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... Astronomy for Kids . ... Observing springtime deep-sky objects with a large telescope . ... Bright planets meet at dusk . ... Astronomy magazine subscribers can read the full article for free. ... Get instant access to subscriber content on Astronomy.com! ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter....

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. ...

SAI VO . ... Web Services . Catalog Access Services . ... SAI Web Services . ... This service aims to automatically match stars in FITS image provided with catalogue and add the correct WCS keywords to its FITS header. ... Service Web Interface . ... The service is available here To use it, you has to provide the image as a Base64-encoded string, along with the rough information on image field of view size and center (the latter may be deduced from FITS header keywords like 'RA' and 'DEC'). ...

Astronomy Discussion Forums . Forums: . Atm ћ Astrophotography ћ Blackholes ћ Blackholes2 ћ CCD ћ Celestron ћ Domes ћ Education . ... Discussion Forums . ... Brightest Northern Hemisphere Galaxy . Forum List | ... Post Message | ... In which constellation would I find the brightest galaxy in the northern hemisphere? ... www.astronomy.net . ... Forum posts are Copyright their authors as specified in the heading above the post. "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...