XMM-Newton observation of the core of the massive cluster Cyg OB2 located in the constellation Cygnus, 4,700 light-years from Earth. The cluster contains massive O-type stars that shine brightly in X-rays. Cyg OB2 #9 is seen as the bright star just below the central star, and in 2008 was determined to be a binary system. ... Hundreds of lower mass stars also fill the field of view, which spans nearly 22 x 16 arcminutes. ...

... Ultraluminous X-ray sources (ULXs) are located in external galaxies, their X-ray luminosities (10 39 - 10 41 erg/s) are thousand times greater than those of brightest black holes in the Galaxy. ULXs may be supercritical accretion disks around black holes of stellar masses (~10 Solar masses) like that in SS433, or they may be a hypothetical intermediate-mass black holes (hundreds - thousands Solar masses) with standard accretion disks. ... 2) The ULX progenitors were ejected from the star clusters. ...

. F IGURE . 2. The distribution of globular clusters projected onto the XY [(a) and (c)] and YZ [(b) and (d)] planes for metal-rich clusters of the thick disk with [Fe/H] -1.0 [(a) and (b)] and metal-poor clusters of the halo [(c) and (d)]. The closed curves are upper envelopes drawn by eye. Clusters lying far from the central concentrations in the diagrams are outlined and their numbers indicated. discussion in the text | previous figure | next figure .

... Bad Astronomy . ... Bitesize Astronomy . ... The next step up are true clusters, called open clusters . Open clusters (sometimes misleadingly called "galactic clusters") are groups of stars ranging in size from a few dozen stars up to tens of thousands. ... The youngest is about 1 or 2 million years old, while the oldest is about 6 or 7 billion years, making it just older than our own solar system. ... So by looking at the stars in the cluster we can tell pretty well how old they are. ...

This page is devoted to information on Supernova 1999gi in NGC 3184 . ... Information on the original web pages for many of these images can be found on the Supernova links web page. ... NGC 3184 is a fairly close Mag 10.3 galaxy, only about half as distant as the Virgo cluster. ... Seiichi Yoshida has a 1999gi page . Odd Trondal's 1999gi page . ... CfA image . ... 14.5 . ... Jean Marie Llapasset image . ... vsnet-alert 3805 ] SN 1999gi in NGC 3184 . vsnet-chat 2438 ] Host galaxy of SN1999gi . ...

... Over the first 4 years, its X-ray telescopes eROSITA and ART-XC will survey the whole sky with a record sensitivity in the 0.5-10 keV energy band. ... The goal of the second international Spectrum-RG conference is to discuss the different scientific topics addressed by the mission, synergies with surveys at other wavelengths, and requirements to follow-up observations.Contributed talks and poster presentations are invited on the topics related to the SRG science goals. ... Active galactic nuclei . ...

Participant 5 (P5) ================== Dr. V.P. Tishkovets - Astronomical Observatory, Kharkov University, UA Dr. N.N. Kiselev - Astronomical Observatory, Kharkov University, UA P.V. Litvinov - 26 years old; Astronomical Observatory, Kharkov University, UA S.A. Beletsky - 28 years old; Astronomical Observatory, Kharkov University, UA The head of the team, Dr. Tishkovets, and Mr. Litvinov made many investigations of light scattering by clusters of particles - analogues of interplanetary dust grains. ...

... Structure of Data . ... Catalog . ... In SAI OCL Catalog, we introduce our work on investigation of the Milky Way system of open star clusters. The main goal of our study is a search for new clusters using huge surveys. 168 new clusters have been already discovered by us using J,H,Ks data from 2MASS point source catalog. ... For 141 new clusters, we found their physical parameters using J,H,Ks data from 2MASS catalog and, for a number of clusters, our UBVRI CCD observational magnitudes. ...

... Astrophysics Group . ... AMI Publications . ... AMI Consortium: Hurley-Walker N. et al., 2011, preprint (arXiv:1103.0947) . ... AMI Consortium: Olamaie M. et al., 2010, preprint (arXiv:1012.4996) . ... AMI Consortium: Shimwell T. W. et al., 2010, preprint (arXiv:1012.4441) . ... AMI Consortium: Davies et al., 2010, preprint (arXiv:1012.3659) . ... AMI Consortium: Franzen et al., 2010, preprint (arXiv:1012.3711) . ... AMI Consortium: Rodriguez-Gonzalvez C. et al., 2010, preprint (arXiv:1011.0325) . ...

ATMoB "Open Cluster Observing Award " Guidelines Purpose: To promote observing among the membership of the Amateur Telescope Makers of Boston through participation in the Open Clusters Observing Awards program. Introduction: This awards program is oriented towards visually observing open clusters above magnitude 9.9. ... It turns out that a very unprejudiced and convenient method to dermine the limiting magnitude is to count the number of visible stars in certain areas on the sky. ...

The Database of Close Binary Systems . ... Team . Docs for editors . ... Anatol M. Cherepashchuk - principal investigator . Igor I. Antokhin - database design, programming and web interface . Editors: . ... Igor I. Antokhin . ... Anatol M. Cherepashchuk . ...

... 320, P L45-L48 (1997). Abstract . ... 320, P L49-L52 (1997). ... 320, P L53-L56 (1997). ... 320, P L57-L59 (1997). ... 320, P 685-695 (1997). ... 320, P 696-704 (1997). ... 320, P 705-716 (1997). ... 320, P 717-730 (1997). ... 320, P 731-745 (1997). ... 320, P 746-756 (1997). ... 320, P 757-775 (1997). ... 320, P 776-782 (1997). ... 320, P 783-786 (1997). ... 320, P 787-790 (1997). ... 320, P 791-798 (1997). ... 320, P 799-810 (1997). ... 320, P 811-822 (1997). ... helpdesk@link.springer.de . ...

... About ATNF overview . ... Parkes | ... A star cluster is a group of stars that share a common origin and are gravitationally bound for some length of time. ... The two basic categories of stellar clusters are open clusters, also known as galactic clusters, and globular clusters. ... Open clusters are so-named due to the fact that the individual component stars are easily resolved through a telescope. ... M67, a very old open cluster has no star hotter than +0.4 colour index left on the main sequence...

ABSOLUTE PROPER MOTIONS OF 331 OPEN CLUSTERS . ... The proper motions of stars in the fields of 331 open clusters were taken from Four-Million Star Catalog (4M-catalog) of positions and proper motions (Volchkov et al. ... The absolute proper motions for 21 young open clusters have been derived by comparison of precise relative proper motions of individual stars and their corresponding absolute proper motions. ... Sign of proper motions in RA . ... 0.0001 arcsec/yr . ... rms error in RA proper motion . ...

IFP gallery SCORPIO (since 2000). Here some data observed on the 6m telescope with IFP installed in the SCORPIO focal reducer are presented. ... Velocity field . Mkn 1157 was observed 1 Sep. 2002 in the Ha emission line. Texp =32x240 sec, seeing 1.5", IFP260. ... This galaxy was observed September, 23 2000 in the Ha emission line, Texp=32x120 sec, seeing 2.5", IFP260. ... PV Cep was observed at the 6m telescope in May, 25 2003 in the [SII] 6716A with IFP501, Texp=36x200 sec, seeing 1.0". ...

... Запорожский клуб АЛЬТАИР > . Catalogue of 109 new Galactic open clusters, for Cartes du Ciel . ... Cartes du Ciel - Sky Charts . ... Этот каталог является версией части каталога "J/A+A/440/403 109 new Galactic open clusters (Kharchenko+, 2005) ", а именно файла stars.dat, содержащего информацию о 26778 звездах до 14.627m , находящихся в 130 рассеяных скоплениях района Млечного Пути (Galactic Open Cluster). ... We present a list of 130 Galactic Open Clusters, found in the All-Sky . ...

FITShdr' package contains set of utilities, that allows to display or modify FITS-file headers (FITS MEF included). ... Both source tarball (see INSTALL ) and i386 RPM are available for downloading: fitshdr-current.tar.gz size: 36379 MD5 checksum: 1e7222149ca36696797a6e0f4af41afc SHA1 checksum: 990bdf69f67d2b989d2d6e044deeaf9128d4470c fitshdr-1.0.6-1.i386.rpm size: 539101 MD5 checksum: 19e046da52b3ec8dd89aaed9e806bb5d SHA1 checksum: 07a4b4e2bd96a4c9fda7dc65127d0b80130c97e1 ...

... Published by the Bureau of Astronomical Communications . ... TITLE OF THE ARTICLE IN RUSSIAN . ... This text contains Instructions for our Authors; at the same time, it shows the general layout of a contribution to the Astronomicheskii Tsirkulyar as it will appear published in the electronic form or printed on paper. ... The text of your article starts here. We accept articles in all branches of astronomy. ... 1543-1548, Information for Authors), text taped and figures drawn on paper. ...

... How to calibrate the energy scale for higher energies of future gratings? Difficult to find astronomical targets with well defined lines. ... Source Energy Flux keV HZ 43 0.2 Bright Sirius B 0.2 HZ43 /10 RXJ1856 1 Faint Simplicity Var WD WD No No No No Yes Yes Extend Lines Point Point Point 1' Point Point Point No Point Point Yes No Yes Yes Yes Yes Point Point , jet Point Cont Cont Cont Cont Lines Cont Lines Lines Lines ...

The ERA Software System Current State and Future Evolution Alexander Fishkov, Dmitry Pavlov, Vladimir Skripnichenko Institute of Applied Astronomy RAS, St. Petersburg, Russia September 25, 2012 ERA : Ephemeris Research in Astronomy · · Domain-specific language for astronomy research ( SLON ) Integrated research environment: editor and interpreter for SLON programs, graphic facilities, table editor 2 Purpose of ...