.

Еще в разделе: (Показать все результаты (>46653) - www.eso.org/ )

• Wide-field view of the bright star clusters Messier 47 and Messier 46 | ESO
• Panning across the bright star cluster Messier 7 | ESO
• Zooming in on the bright star cluster Messier 7 | ESO

Today's APOD | ... Editor's choices for the most educational Astronomy Pictures of the Day about open clusters: . APOD: 2006 January 9 - M45: The Pleiades Star Cluster . ... The Pleiades contains over 3000 stars, is about 400 light years away, and only 13 light years across. ... Two types of star clusters are visible in our Milky Way Galaxy : open clusters and globular clusters . ... Aged 80 million years, M47 is a smaller but looser cluster of about 50 stars spanning 10 light-years. ... Index | ...

Еще в разделе: (Показать все результаты (>4262) - www.sai.msu.su/ )

• APOD: 2003 December 15 - Open Star Clusters M35 and NGC 2158
• APOD: 2002 November 29 - Open Star Clusters M35 and NGC 2158
• APOD Index - Galaxies: Clusters of Galaxies

... 1.05.2013 . ... Of the 200 or so globular clusters that survive today, Omega Centauri is the largest, containing over ten million stars. ... Unlike many other globular clusters , the stars in Omega Centauri show several different ages and trace chemical abundances, indicating that the globular star cluster has a complex history over its 12 billion year age. ... Publications with keywords: Omega Centauri - globular cluster . Publications with words: Omega Centauri - globular cluster . ...

Еще в разделе: (Показать все результаты (>108588) - www.astronet.ru/ )

• Clusters and Nebulae of the Hexagon
• Open Star Clusters M35 and NGC 2158
• Астронет > Open Star Clusters M35 and NGC 2158

Stellar Clusters are very useful laboratories for empirically studying stellar evolution. ... All cluster stars are at the same distance . All cluster stars have the same physical age . ... CM diagram Young Cluster In this case we see the Main Sequence fully represented. The blue dots represent massive stars with short main sequence lifetimes. ... Thus, identifying the most massive star which is still on the main sequence is an effective means of determining the age of a stellar cluster. ...

Еще в разделе: (Показать все результаты (>113) - zebu.uoregon.edu/ )

• The Galaxy Gallery Page IX: Clusters of Galaxies
• Astro-2 and the UIT Experiment

... Radio source identifications . The Web-server of the Special Astrophysical Observatory supports the mirror version of the Clusters of Galaxies database . At present only the data about radio sources in ACO clusters of galaxies are reasonably complete, while only restricted optical information is in our database. Later on, we also intend to include X-ray data and data about brightest cluster galaxies (BCG). ... ACO: radio optic ( for example, A0690 and " optic "), . ...

Еще в разделе: (Показать все результаты (>520) - www.sao.ru/ )

• A 20 cm VLA survey of Abell clusters of galaxies
• A 1400-MHz Survey of 1478 Abell Clusters of Galaxies
• A VLA Survey of Rich Clusters of Galaxies I.

... This paper ( Burke et al. 2003 ) describes the creation of one such catalogue - the Southern Serendipitous High-redshift Archival ROSAT Cluster (SHARC) survey - which covers an area of 17.7 deg 2 and consists of 32 clusters with redshifts between 0.05 and 0.7 and X-ray luminosities between 7 x 10 42 and 4 x 10 44 erg/s: the high-redshift subsample contains 16 clusters with = 0.3 and X-ray luminosities greater than 2 x 10 43 erg/s (luminosities are quoted for the 0.5 - 2.0 keV energy band). ... 1997 ...

Еще в разделе: (Показать все результаты (>1002) - hea-www.harvard.edu/ )

• Doug Burke: Publications List
• The AstroStat Slog clusters
• The AstroStat Slog Globular Clusters

... 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. ...

Еще в разделе: (Показать все результаты (>150) - mavr.sao.ru/ )

• important_en
• articles_flera_en

... From the data taken during Cycle 1, surface brightness profiles have been obtained for 13 globular clusters in M31 (Fusi Pecci et al. 1993), leading also to the detection of a central cusp in a candidate post-core-collapse cluster (Bendinelli et al. ... Surface brightness profiles obtained with VISTA. ... PSF 512 512, data matrix smaller and smaller (256 256, 128 128, 64 64), sky = 0, RMG (Fig. 3b): the derived profiles remain unaffected a part from the reduction in radial extension. ...

Еще в разделе: (Показать все результаты (>9335) - www.stsci.edu/ )

• STScI Preprint #1297
• STScI Preprint #1256
• Simulation of a Distant Cluster of Normal Galaxies

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. ...

Еще в разделе: (Показать все результаты (>274) - www.atmob.org/ )

• Amateur Telescope Makers of Boston ATMoB Observing Awards Program

Astronotes Armagh Planetarium's Stellar Blog! ... Comets and Asteroids . ... Image credit:ESO/J.Emerson/VISTA. ... However others are less pessimistic and it has even been claimed that the mysterious ?Wow! signal? received in 1977 originated from the direction M55.б  Sadly, this still unexplained pulse of radio energy originated from a location rather to the northwest of M55 so I doubt if the source was this cluster (if indeed the signal was genuinely of extraterrestrial origin). ... Mysterious Wow! ...

Еще в разделе: (Показать все результаты (>1892) - www.armaghplanet.com/ )

• NGC4666: Secrets of a Starburst Galaxy | Astronotes
• Omega Centauri: globular cluster of 300,000 stars | Astronotes

... 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. ...

Еще в разделе: (Показать все результаты (>222) - ocl.sai.msu.ru/ )

• SAI OCL Catalog Publications
• SAI OCL Catalog Structure
• SAI OCL Catalog Description

home publications > mercury . ... Big Clusters, Tiny Galaxies . ... Astronomers struggle to understand why giant star clusters form in the tiniest of galaxies . ... These clusters are probably young versions of globular clusters, but they are commonly called super star clusters. Seven dwarf galaxies within 16 million light-years have formed super star clusters, with one of these galaxies, NGC 1569, possessing two young clusters. ... Super star clusters have a lot to tell us about star formation. ...

Еще в разделе: (Показать все результаты (>398) - www.astrosociety.org/ )

• ASP: Globular Clusters and Satellite Galaxies: Companions to the Milky Way
• ASP: Star Science in the Autumn Sky
• ASP: NGC Images on the Net

... BLUE STRAGGLER STARS are unusually hot and bright stars found in the cores of ancient star clusters known as globulars. ... BACKGROUND (from wikipedia): Blue straggler stars are stars in open or globular clusters that are hotter and bluer than other cluster stars having the same luminosity. ... There is evidence in favor of this view, notably that blue straggler stars appear to be much more common in dense regions of clusters, especially in the cores of globular clusters. ...

Еще в разделе: (Показать все результаты (>328) - www.mso.anu.edu.au/ )

• GSAOI Super Star Clusters Science Page
• IAU Commission #37 (Star Clusters and Associations)
• GSAOI Open Cluster Science Page

... 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. ...

Еще в разделе: (Показать все результаты (>162) - www.badastronomy.com/ )

Proposal Identi cation No.: A1511 Date Received: 2001-Feb-01 17:39:36 Technical Page Proposal Type: Regular General Category: Astronomy Sub-Category: Spectroscopy Observation Category: Extragalactic Total Time Requested: 20 Hours Proposal Title: Low Surface Brightness Galaxies in X-ray Emitting Clusters ABSTRACT: Successful surveys for the detection of low surface brightness disk galaxies have been primarily undertaken in spiral rich clusters with little or no X-ray emission. ...

Еще в разделе: (Показать все результаты (>883) - www.naic.edu/ )

• Pulsar Highlights - A Dozen new MSPs in Globular Clusters
• The Pleiades

... LMC Project Outline . NGC 1818 Initial Results . ... The Large Magellanic Cloud (LMC) is uniquely suitable for the study of massive star clusters at all stages of evolution. By combining HST observations of these clusters with N-body models we hope to understand the origin and evolution of rich star clusters in our own Galaxy, in the LMC, and beyond. ... We aim to combine our HST observations with N-body models to understand the formation and evolution of globular clusters. ...

Еще в разделе: (Показать все результаты (>103) - www.stecf.org/ )

• ESLAB 2007
• NICMOS/HST H-band (F160W) Images of the 30 Dor Starburst Cluster

This image from the NASA/ESA Hubble Space Telescope shows NGC 6388, a dynamically middle-aged globular cluster in the Milky Way. ... A new study using Hubble data has discovered that globular clusters of the same age can have dramatically different distributions of blue straggler stars within them, suggesting that clusters can age at substantially different rates. Credit: NASA/ESA/F. Ferraro (University of Bologna) ...

Еще в разделе: (Показать все результаты (>6190) - www.astronomy.com/ )

• The Queen's clusters | Astronomy.com
• stars and star clusters | Astronomy.com
• open clusters | Astronomy.com

Searching for Ultra Compact Binaries in Globular Clusters What Are Ultra Compact Binaries? ... An ultra compact binary is a binary that consists two white dwarf To source the FITS files that contained the UV images, the sky coordinates stars and has an orbital period shorter than ~70min (A binary and the details on brightness for each star in each globular cluster we were consists of two stars orbiting around their centre of mass, it enables investigating, we used the XMM online archive. ...

Еще в разделе: (Показать все результаты (>1434) - star.arm.ac.uk/ )

• Armagh Observatory
• SELB Schools Cluster Programme Show | International Year of Astronomy - Beyond
• William Herschel

... The most powerful and widely used methods to calculate the scattering matrix of a fractal cluster are based on the coupled dipoles methods (e.g. the Discrete Dipole Approximation, DDA) and the theory of light scattering by a cluster of spherical particles [2-4]. ... At present the procedure of calculation of the scattering matrix is well developed for both an oriented cluster of spherical particles and for chaotically oriented clusters of such particles [4]. ...

Еще в разделе: (Показать все результаты (>114) - www.astro.spbu.ru/ )

... Current Work ­ Attempting to understand AGN feedback in galaxy clusters AMI ­ Where does AMI fit in? ... Feedback needed to offset cooling and explain the deficit of cold, molecular gas in cluster cores. ... Some already observed with AMI ­ Ideally want to observe many more (~100 ­ 150) cooling clusters in this energetically important but often overlooked frequency range. ... If bright at 1.4GHz then observe with AMI Campaign to observe many clusters at higher frequency with GISMO (2mm). ...

Еще в разделе: (Показать все результаты (>816) - www.mrao.cam.ac.uk/ )

• Abstract
• PPEUC Programme - Cosmic Microwave Background Workshop
• Astrophysics Group AMI-Planck