... The task first computes a background image in order to identify pixels that may be part of a source. The task uses two different algorithms for detecting ``point'' and ``extended'' sources. ... This is necessary because some faint ``point'' sources may have been missed by the point-source detection algorithm, but picked up by the extended-source detection algorithm. ... When the detection process is finished a check is made on extended sources to see if they can be split into two or more sources. ...

Stellar photometry of simulated HST uncorrected and corrected images of a crowded star cluster has been carried out before and after deconvolution (with RMG, R-L, MEM, etc.) to optimize the reduction procedures and compare the degree of completeness and photometric accuracy actually achievable in the various cases. ... Pages 319-326 . ...

... The procedure of radiometer signal integration can be considered as a sort of reducing dimension of the initial sampling space, where the samples are the result of analog-to-digital conversion. ... The probability distribution of the signal and spikes is completely known. ... The quality of the considered algorithm could be also illustrated by Figure 2 . ... One could see the considered adaptive algorithm is preferable even by low degree of compression, because all spikes have been depressed. ...

. There are several different shells available for Unix; the most popular are described here. You can use any one of these shells if they are available on your system. And you can switch between the different shells once you have found out if they are available. Bourne shell (sh) . C shell (csh) . TC shell (tcsh) . Korn shell (ksh) . Bourne Again SHell (bash) .

... This is possible at modest cost due to the low moments of inertia of the telescope and enclosure. ... This same performance will be achieved in higher winds when the telescope enclosure is facing away from the wind, or by using wind screens. ... The telescope system (MILT) will be remotely operable with an on-site operator's assistance by an astronomer located at one of the ARC member institutions. ... Mean Wind Speed . ... Offsets > 10 deg: 1 arc sec rms max . ... 5 sec max, tracking to tracking . ...

... It provides long range planning information to the scheduling team; it provides bright object, timing, and orientation information to the observation planning team; and it provides graphical description of the observations and their constraints. ... The GUI graphically displays the constraints that are computed by Spike and stored in the description files and in the database. ... BOAS processes all bright objects that have entered the database since the last time BOAS was run. ...

... 173Wall Peacock We catalogue the brightest extragalactic radio sources at 2.7 GHz. ... These data were originally presented in Wall and Peacock, MNRAS, 216, 173. The values in parenthesis include (units, datatype, example). 1 iauname Name of source in IAU convention (char7, example: '0320-37') . ... 3 ra_1950 rad Right ascension of source in radians (B1950) (real, example: 0.876068) . ... 9 alpha Spectral index of source between 2.7 and 5 GHz (real, example: 0.52) . ... Longair, 1975 . ...

... Centrifuge . ... The major factor of the orbital flight, affecting a cosmonaut, is a weightlessness state, which causes essential changes in cardiovascular and vestibular systems operation. ... In addition, you can experience a long-term G-load in a desirable value and direction, including simulation of the typical test profiles for fighter - pilots and cosmonauts. ... Info: Industry news On-line Data Company ATLAS news Events We in press Contact . Copyright 2000-2016 ATLAS Aerospace . ...

grdsample - Resample a grd file onto a new grid grdsample in _ grdfile -G out _ grdfile [ -F ] [ -I dx [ m|c ][/ dy [ m|c ]] ] [ -L flag ] [ -N nx / ny ] [ -Q ] [ -R west / east / south / north [ r ] ] [ -T ] [ -V ] grdsample reads a grdfile and interpolates it to create a new grdfile with either: a different registration ( -T ); or, a new grid-spacing ( -I ) or number of nodes ( -N ), and perhaps also a new sub-region ( -R ). ... G The name of the output grd file. ... Default is grid registration]. ...

... Outline of the BTF paper by Erwin de Blok (25-2-2002) ----------------------------------------------------- * Description of sample * Data and corrections * Descriptions of method to measure line widths * Description of method to measure inclinations * Corrections to linewidths and magnitudes (inclination, random motion, instrumental resolution, extinction) * Corrections to recession velocities (to Local Group frame, also POTENT etc for nearby galaxies) * Describe B-band ...

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. ...

Two major reasons: the number of stars isn't really seven (it's many more), and they all have different brightnesses, so that you see more or fewer of them depending on viewing conditions. The brightness of stars is measured on the magnitude scale, where the most prominent stars in the sky are around 1st magnitude, and the faintest you can see with your eye are about 6th. ... I think this makes it quite likely that the list will be truncated at Taygeta, giving six visible stars. ...

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. ...

... Model . ... Karpachev A.T., IZMIRAN, e-mail: karp@izmiran.ru . ... To the Model: . The empirical median model of the shape and position of the MIT (Main Ionospheric Trough) in the Northern and Southern Hemispheres is presented. ... Geomagnetism and aeronomy, v.26, № 1, p.63-68, 1986. ... Karpachev A.T., Afonin V.V. Dependence of the ionospheric trough occurrence probability on the season, local time, longitude, and level of magnetic activity Geomagnetism and aeronomy, v.38, № 3, p.79-91, 1998. ...

... Co-ordinate systems description . Directories structure . The file names' construction . The file set description . ... The orbital information for each month is presented in the separate directory. The INTERBALL orbital data are located on the STDA server, for each month in the separate subdirectory, which name consists from the year (YYYY) and month (MM) numbers. The Parent Directory of the Tail Probe orbital data is http://www.iki.rssi.ru/da/interball/tail/orbit/ . ...

The Doppler shift is the effect of sound increasing or decreasing in pitch as an object moves towards or away from you. ... Light works the same way, except light is shifted to redder colours when an object is moving away, and to blue colours when an object is travelling towards us. ... Almost every object he observed had its light stretched to redder colours, indicating essentially everything in the Universe was moving away from us. ... So the Hubble constant tells us how old the Universe is. ...

... Description . Catalog . ... In the Catalog, we publish equatorial (ЮБ 2000 , ЮД 2000 ) and galactic (l,b) coordinates of cluster centers derived as the position of overdensity in 2MASS catalog (Koposov et al. ... Distances, color-excesses and ages are the mean-square values calculated using all available evaluations from different color-magnitude diagrams. ... There are individual pages for every cluster where all available plots and parameters are published. ... 2002). ...

The following papers summarize the characterization and technical performance of IBIS : . ... Characterization of Fabry-Perot interferometers and multi-etalon transmission profiles. ... Righini, A., Cavallini, F., Reardon, K. P., 2010, Astronomy and Astrophysics , 515 , A85, . ... The filter wheel is located between the two interferometers. ... The interferometers can be rapidly tuned, simultaneously, so to allow sequential scanning of the spectral lines of interest (see movie in IBIS Intro ). ...

... Telescopes . ... Diameter of circular antenna . ... Number of antenna elements . ... Geometrical area . ... Effective area of full circle . ... Wavelength range . ... Frequency range . ... 2 arcsec . ... Flux density limit . ... Absolute brightness temperature limit . 0.050 mK . ...

The database contains references to the papers, data files and links to the Internet resources related to measurements and calculations of the optical constants in the wavelength interval from X-rays to radio domain. ... References to some useful books and reviews on the subject (e.g. the classical handbooks edited by E.D.Palik) and links to Internet collections of optical constants and personal WWW pages with related software were also placed in the database. You have arrived at our welcome page. ...