... astro-ph/0003002 We cross-identified the ROSAT Bright Source Catalog (RBSC) and the NRAO VLA Sky Survey (NVSS) to construct the RBSC-NVSS sample of the brightest X-ray sources (~0.1 counts s^{-1} ~= 10^{-12} ergs cm^-2s^-1 in the 0.1--2.4 keV band) that are also radio sources (S ~= 2.5 mJy at 1.4 GHz) in the 7.8 sr of extragalactic sky with |b| > 15deg and DEC > -40deg. ... We used the more accurate radio positions to make reliable X-ray/radio/optical identifications down to the POSS plate limits. ...

... They worked out that first magnitude was on average 100 times brighter than the 6th magnitude star. ... This formed an equation of apparent magnitude Mv which is: Mv = -2.5 log f + constant were f is the flux of that star f = ( counts/ exposure) The images that we worked on were taken by the Polar Bear Telescope. ... One of these being that it will be combined with standard stars, which will be used to identify the area of stars and to also help identify other stars within the image. ...

... The ROSAT Bright Survey: II. Catalogue of all high-galactic latitude RASS sources with PSPC countrate CR > 0.2 s -1 . ... 1S We present a summary of an identification program of the more than 2000 X-ray sources detected during the ROSAT All-Sky Survey (Voges et al. 1999) at high galactic latitude, |b| > 30degr , with countrate above 0.2 s -1 . This program, termed the ROSAT Bright Survey RBS, is to more than 99.5% complete. ...

ST ScI Preprint #1380 . Authors: A. A. Suchkov, 1 M. McMaster 1 We find evidence for the presence of a population of numerous binaries with comparably bright components (C-binaries) among HIPPARCOS F stars that are flagged in the HIPPARCOS catalogue as single. ... The criterion is based on comparison of absolute magnitude M V obtained from the HIPPARCOS parallax and Johnson V magnitude with absolute magnitude derived from the dereddened uvby luminosity index c 0 , M c 0 . ...

ATNF Annual Report 2000 (submitted) . ... One of the first products is the HIPASS {\it Bright Galaxy Catalogue}, which is a catalogue of the 1000 apparently brightest HI galaxies in the southern hemisphere. ... In Figure 1 we show the spatial distribution of the brightest HIPASS galaxies. ... Figure 4 shows the velocity distribution of the 1000 brightest HIPASS galaxies (orange) compared to the 1000 brightest optical galaxies (selected from the Lyon/Meudon Extragalactic Database using blue magnitude). ...

Astronomy Picture of the Day . ... What's causing those odd rings in supernova 1987A? Twenty five years ago, in 1987, the brightest supernova in recent history was seen in the Large Magellanic Clouds. ... The first identified compact galaxy group, Stephan's Quintet is featured in this eye-catching image constructed with data drawn from the extensive Hubble Legacy Archive. ... Aurigae Nebulae . ... Barred Spiral Galaxy NGC 1073 . ... A Message From Earth . ... At the West Wall of Aristarchus Crater . ...

USING THE CORRELATION BETWEEN ISGRI SURVEY RESULTS AND OTHER CATALOGUES TO AID SOURCE IDENTIFICATION John B. Stephen, A. Malizia and L. Bassani IASF-INAF, Via P. Gobetti 101, 40129 Bologna, ITALY, E-mail: stephen@iasfbo.inaf.it ABSTRACT In order to help in the identification of INTEGRAL/ISGRI sources, we have developed a software package which allows a rapid and detailed cross-correlation to be performed between various source catalogues. ... We show below some preliminary results from this analysis. ...

... This file table3.dat 108 715 YSO candidates in the ISOGAL survey -------------------------------------------------------------------------------- Byte-by-byte Description of file: table3 ... Format Units Label Explanations -------------------------------------------------------------------------------- 1- 24 A24 --- Name ISOGAL source name (based on J2000 coordinates) 26- 33 F8.4 deg Glon Galactic longitude 36- 42 F7.4 deg Glat Galactic latitude 44- 48 ...

A bright supernova, 1998S, has been found on March 3 by Chinese astronomers at Beijing Observatory. 1998S is located in NGC 3877 an UMa galaxy at R.A. = 11h46m06s, Decl. = +47o29'.0. ... Recent magnitude estimates show the star at around magn 12. ... It covers a field of 35'x35' and shows stars down to magnitude 15 and is mainly based on the GSC and USNO catalogues. ... Below follows a list of field and sequence stars located within ~20' from SN 1998S in NGC 3877: . ... TI (b-r)=+0.5 . ...

... The Galactic low-mass X-ray binary GS 2023+338 was discovered during the burst on May 22, 1989 with the Japanise satellite Ginga (aka Galaxy). The flux reached 17 crabs (this unit of flux measurement is an bright X-ray source, Crab Nebula) at 10-35 keV. ... No other radio telescope worldwide carried out multi-frequency measurements. ... Upon 14 days the radio flux fell below the detection level at the RATAN-600 in relation to the decrease of the X-ray flux. ...

Dear PALFA consortium members, Another smooth day of observing, with detections of J1928+1746 (PALFA#1), a much brighter re-detection of B2020+28, a few single-pulse candidates, and not much else to report from our quicklook. ... Update databsae with fill_observed.py Quicklook Notes: * Plot order bug: displays candidate 1, 10, 2, 3, .. Plot display bug: If the last candidate (#9 for now) is filtered out, then the single pulse plot is also filtered out. ... No other obvious quicklook candidates. ...

... General Catalog of Variable Stars (GCVS database, Version 2012 Feb.) ... The cross-identification tables of the General Catalogue of Variable Stars (GCVS) contain all GCVS (including extragalactic variables from vol.V), NSV (New catalogue of Suspected Variable stars) and Supplement to the NSV stars as well as stars from the name-lists of variable stars nos. 67 - 80; it also makes it possible to find out identifications between the GCVS and the NSV catalogue. ... I-III) names are included. ...

. Please standby and you will be automatically connected to the new location of the unframed Supernova page. Or, click on the link above. If you have questions or problems, please email me at David Bishop dbishop@vhdl.org . Last modified: Mon Aug 27 12:40:15 EDT 2001

... We report initial results of cross-identification of extragalactic objects from the NASA/IPAC database and Guide Star Catalog (GSC). ... The NASA/IPAC Extragalactic Database (NED) contains positions, extensive data, and 1,023,000 cross-identifications for over 592,000 extragalactic objects (galaxies, quasars, and radio sources). ... Catalogs and lists are being integrated into NED on a continuing basis, following a detailed cross-identification process. ... Final cross-identification results: . ...

Download Izmccd (~2.7 MB). Solution of problems at identification of star field. ... 2) Scale is not correct. ... In this case algorithm of identification will revise all values of scale from twice smaller up to twice greater. ... There should be more than value of the field "Number of stars in frame". ... The star field is considered identified if number of the identified stars more or equally to this value. It is necessary to set value from 4 up to value of field "Number of stars in frame". ...

Definitions of Magnitudes and Surface Brightness 1 The magnitude system 1.1 Apparent magnitude Astronomers are stuck with the antiquated old system of magnitudes and so a clear explanation of what this system is and how it relates to more sensible units is important. ... 1.2 Absolute magnitude Absolute magnitude is a logarithmic luminosity scale. ... One usually goes by the round about process of referring to the absolute magnitude of the sun. ... Magnitudes and surface brightness 6/6 ...

October 30-31, 1992 . ... Modified images of the October 30-31, 1992 event. (a) - This NRH image is adapted to show a very bright loop-like source over AR 7321 near the SW-limb identified with the X1.7 soft X-ray LDE event peaked on 30d at 17:30 UT (see the GOES-7 soft X-ray plot also at the upper right corner). ... Here and hereafter, the white features are radio filaments. (c) - This modified NRH image shows some large scale microwave blob chains and structures. ...

Next: Identifications and Efficiency Up: THE DEEP X-RAY RADIO Previous: Source Classification . ... For some sources which did not have NVSS positions before the time of optical observations, arcsecond positions from the Texas survey (Douglas et al. 1996) and NED (typically based on VLA data) were used. ... All X-ray/radio sources without counterparts on the survey plates were imaged at either the KPNO 0.9m or the CTIO 0.9m telescopes. ... Previously Identified Sources . Sample Properties . ...

The ESA/ESO Astronomy Exercise Series 2 . The Distance to Messier 100 as Determined by Cepheid Variable Stars . ... The small variations in distance to the individual Cepheid variable stars in the Cloud are negligible compared with the much larger distance to the SMC. ... In this way Cepheid variable stars can be used as one of the 'standard candles' in the Universe that act either as distance indicators themselves or can be used to calibrate (or set the zero point for) other distance indicators. ...

... This image shows clearly the 3-D structure of this star formation region: a large cavity, created by the radiation pressure from new-born stars located in the brightest area of the image, lies within a huge cloud of dust and gas. Identified as a truly indepedent star cluster, NGC 1980 is associated with this well-studied star formation region, around the brightest star seen at the bottom of this image, Iota Ori. ...