... In most astronomical observations the image intensity consists of contributions from both object and sky background. Depending on the complexity of the field and the type of object, different methods are used to estimate and subtract the background intensity. ... Non--linear filters are often used to remove stellar images and other sharp features (see Section ) while extended objects are very difficult to eliminate automatically. ...

SAI 175 anniversary . ... Moscow University . Search for in SAI Moscow University Search for in Russian astronomical resources . ... SAI Astronomical Databases . ... Browse SAI Software archive(ftp.sai.msu.su) . ASTRONET.RU - Russian Astronomical Network (available in translit also) . ... SAI Supernovae Research Group . ... Department of the Galaxy and Variable Stars (in Russian) . Sternberg Astronomical Institute Seminars . ... All-Russian Astronomical Olympiad (in Russian) . ...

... Donate to Support Science Literacy . ... 2016 Annual Awards . The ASP is accepting nominations for the organizationтАЩs national annual awards which recognize special achievements in astronomy research, technology, education, and public outreach. ... Shop the AstroShop . ... The Astronomical Society of the Pacific (ASP) is accepting nominations for the organizationтАЩs national annual awards which recognize special achievements in astronomy research, technology, education, and public outreach.. ...

... This paper describes the main algorithms used by the Einstein Level One processing to create the exposure masks and the background maps for Einstein IPC images, and how these algorithms were recreated in the IRAF environment. Our goal was to recreate the algorithms used by the Level One Processing to create exposure masks and background maps for Einstein Image Proportional Counter (IPC) data (cf. sections 2.5 and 2.7 of Harnden et al. ...

Next: Photometry Up: Regions and Source Parameters Previous: *imcnts* - Find counts . This task (developed for use with optical images, but also useful with x-ray data) will quickly compute location, size, ellipticity, and position angle of sources. ... User can generate contour plots of any portion of the image and count rates in slices through the image. The program is advertised as ``quick [optical] photometry''. input file: rp110590_im1.imh . output file: logfile . ... Photometry . ...

The Astronomical Catalog portion of CDBS contains several atlases consisting of both observed and model stellar,galactic, and emission line object spectra as well as HST standard stars spectra are available in STSDAS table format for use in the calibration of HST instruments, with synphot, with the exposure time simulators, or for any other purpose. this is it There are two independent directories containing the spectra of ultraviolet and optical standard stars. ... For details see K93MODELS . ...

... This thread contains a step-by-step recipe to extract MOS spectra of a point-like source observed in Imaging mode and to create associated response matrices, starting from a calibrated, concatenated event list (either produced with emproc or available as PPS product; here it has the assumed file name MOS.fits ). ... The users should note that the SAS metatask xmmselect allows them to interactively define source and background regions (via ds9) and to run backscale on the fly. ...

... Астрономическая неделя с 11 по 17 апреля 2016 года . ... Александр Козловский . ... День открытых дверей на Пущинской РадиоАстрономической Обсерватории 09 апреля 2016 года . ... Полное солнечное затмение 9 марта 2016 года . ... Полное лунное затмение 28 сентября 2015 года . ... Затмение, которое произойдет 28 сентября 2015 года, является повторением через сарос (цикл повторений затмений равный 6585 дней или 18 лет 11 дней) полного лунного затмения от 16 сентября 1997 года с максимальной фазой 1,20.....

. Pulkovo Observatory of Russian Academy of Sciences is situated . near Saint-Petersburg. It was founded in 1839. 196140, Saint-Petersburg, Pulkovskoye chaussee 65/1 . English version . Russian version . This page has been accessed times since May 1, 1999.