... Next: The PROS Big Up: Software Systems Previous: Data Reduction Software . ... The srcinten task provides PROS users with a tool to compute count rates for point sources in the ROSAT High Resolution Imager (HRI). ... Corrected upper limits are cited at locations where the count rate falls below the source detection threshold. ... Srcinten is a new PROS task that computes and applies the above correction factors to the net counts in a user-specified aperture. ...

... Chandra | ESO | ... Field selection . ... Color composite image of the Chandra Deep Field South of 940 ks (pixel size = 0.984 arcsec, smoothed with a s =1 arcsec Gaussian). ... The Chandra Deep Field South (CDF-S) is one of the deepest observations obtained with the X-ray Chandra satellite, which stared at the same path of the sky for 11 days. ... ESO press release on March 13 , 2001 . ... APOD : The Chandra Deep Field South has been the Astronomical Picture of the Day on March 28, 2001 . ...

... The stars examined here were primarily culled from two lists of X--ray sources in Orion. ... The second region is two degrees in extent east--west and ten degrees north--south with Orionis being near the northern edge. ... In the end, two main regions were chosen for monitoring: stars near Orionis and stars northwest of the belt of Orion. ... The PSPC identified 22 sources within 15 of Orionis in addition to the sources listed in Table 1 , giving a total of 85 X--ray sources in the Orionis region. ...

... Duchamp | ... Top | Duchamp is a solution to this problem of three-dimensional source finding. ... A list of the detections and their properties, as well as the input parameters that were used. [text file] . ... It can be downloaded in source format, in a gzipped tar archive. ... Changes from the previous version can be seen here (this file is included in the tar archive), while the archive files and documentation from the previous release versions are here , if you are really interested. ...

The Arcetri Catalog contains measures and bibliographic data for all known H2O maser sources north of declination = -30 degrees (to be observable with the Medicina radiotelescope). ... This database is fully described in Cesaroni et al. ... A statistical analysis on the atlas has been carried (Palagi et al 1993). R. Cesaroni, F. Palagi, M. Felli, M. Catarzi, G. Comoretto, S. Di Franco, C. Giovanardi, F. Palla: A Catalogue of H2O maser sources north of delta=-30 , Astronomy and Astrophysics Suppl., ...

... Tonight's Sky . ... The Magazine . ... Observing . ... Magazine . ... Gravitational wave search provides insights into galaxy evolution and mergers . ... galaxies . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... Astronomy for Kids . ... Resources for red-star fans . ... Get instant access to subscriber content on Astronomy.com! ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter. ... Astronomy Magazine ...

... 19 љ*</tt>: landscape textures and data files</li> . ... 73 љIf a file exists in the <em>User Data Directory</em>, it will be used in preference to a file with the same name existing in the <em>Installation Data Directory</em>. ... 79 љ <li>Users who modify files in the <em>Installation Data Directory</em> will likely have their work deleted or overwritten when they upgrade Stellarium. ... In this case , all the files would be in the <em> \<Installation Data Directory>/stars/default</em> directory. ...

... Articles | ... Forums . ... 230 deg . 49 deg . ... 130 deg . ... More Info . ... 210 deg . ... 168 deg . ... 249 deg . ... 195 deg . ... 271 deg . ... 110 deg . ... 338 deg . ... July 15 . 247 deg . ... 224 deg . ... 340 deg . ... July Phoenicids (PHE) . ... August 10 . 341 deg . ... 339 deg . ... 307 deg . ... 334 deg . ... 335 deg . ... 286 deg . ... 327 deg . ... 262 deg . ... 102 deg . ... 153 deg . ... 117 deg . ... December 2 . ... 123 deg . ... 100 deg . ... www.astronomy.net . ...

Statistics of sunspot activity . The sunspot indices . ... NGDC's observations . The solar regions . ... Average annual indices . ... August . ... August, 2013 . Visual indices of solar activity by National Geophysical Data Center . ... Average . ...

... The two bright sources at the center of this composite x-ray (blue)/ radio (pink) image are co-orbiting supermassive black holes powering the giant radio source 3C 75. ... Mars: The View from HiRISE . ... During the March 29 total solar eclipse, the Moon's dark central shadow or umbra is vanishing beyond the horizon in this dramatic view of the landscape a few kilometers southeast of Incesu, Anatolia, Turkey. ... Some views of last week's total eclipse of the Sun were better than others. ...

Orbit . ... The orbit of the RadioAstron provides four types of st