... 2013 May 1 . Omega Centauri: The Brightest Globular Cluster . ... Explanation: This huge ball of stars predates our Sun. ... 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. ... About APOD | ...

... Credit: L. Drissen, J. Roy and C. Robert ( Universite Laval ), Y. Dutil ( CFHT ), NASA Explanation: These two clusters of bright, newly formed stars surrounded by a glowing nebula lie 10 million light-years away in the dim, irregular galaxy cataloged as NGC 2366. ... Compared to the sun, the stars in these clusters are massive and short lived . ... Publications with keywords: star cluster - Eta Carinae - NGC 2363 - irregular galaxy - star formation - massive stars . ... X Ray Stars of Orion . ...

Why areNuclear Star Clusters interesting? 1) Many -- if not all ­ nuclear star clusters appear to be young, or at least have a young population of stars. ... 3) If nuclear clusters indeed form in the galaxy center, their impact on the dynamics of stars and gas in the central region of the host galaxy needs to be understood, because it can potentially influence the galaxy morphology. For example, it has been suggested that nuclear clusters can destroy stellar bars and thus form galaxy bulges. ...

... 2000 August 4 . M15: Dense Globular Star Cluster . ... In fact, only 40,000 light-years away in the constellation Pegasus, M15 is one of the most densely packed globular star clusters in our Milky Way Galaxy. This stunning Hubble Space Telescope image of M15 shows thousands of individual stars across the central 10 or so light-years of the cluster, also cataloged as NGC 7078. ... Globular star clusters harbor from a hundred thousand up to a million stars and roam the Milky Way halo. ...

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! ...

... My primary research interests are the formation and evolution of nuclear star clusters. ... Nuclear star clusters are common objects in nearby galaxies. ... Feldmeier-Krause, A. ; Neumayer, N.; SchУЖdel, R.; Seth, A.; Hilker, M.; de Zeeuw, P. T.; Kuntschner, H.; Walcher, C. J.; LУМtzgendorf, N.; Kissler-Patig, M. Astronomy Astrophysics, accepted, 2015 . ... SchУЖdel, R.; Feldmeier, A. ; Neumayer, N.; Meyer, L.; Yelda, S. Classical and Quantum Gravity, Volume 31, Issue 24, 12/2014 . ... 2014 . ...

... 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. ...

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. ...

ATNF Home . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Astrophysics graduate student programs . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . ... Mopra radio telescope . ... The Australia Telescope National Facility Colloquium . ... The mass spectrum scales as N(M) ~ M^-1.5, similar to the mass spectra of young massive star clusters suggesting that individual molecular clouds are transformed in the starburst into individual star clusters. ...

A Canadian and American team of Astronomers have used the 305-m wide Arecibo radio dish, the world's largest and most sensitive radio telescope, to uncover a dozen new super-fast-spinning pulsars. The team directed their search for these rare and exotic stars by pointing the Arecibo radio telescope towards massive star clusters, called Globular Clusters, orbiting our Milky Way galaxy. ... One of the most exotic residents in the Globular cluster system are the millisecond pulsars. ...

... We have made observations of the Perseus cluster with the Westerbork Telescope at 610 MHz. ... Several newly detected sources are identified with cluster galaxies. ... No evidence is found for the existence of the previously reported ~ 65'x25' cluster halo, 3C 84B. Key words: radio galaxies - clusters - tailed radio sources buoyancy The Perseus Cluster of galaxies is one of the most fascinating systems accessible to extragalactic astronomers. ...

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. ...

... We address a question if globular clusters (GC) in a protogalaxy could for some time evolve chemically as isolated systems, enriching themselves with heavy elements produced in first supernova events that follow initial star formation. We determine both the critical mass of a protoglobular cluster that is needed to retain the ejecta of the very first supernova, and the critical energy (i.e., number of supernovae) that is needed to expel the residual gas from a cluster of a given mass. ...

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. ...

... All previous such superstars have been found along with many companion stars in the centres of crowded star clusters. The star is known as VFTS 682 from the VLT-FLAMES Tarantula Survey catalogue of the European Southern Observatory's Very Large Telescope (VLT) located at Paranal in Chile by means of the attached FLAMES instrument. ... Although VFTS 682 seems to be alone now it is not very far away from a very rich star cluster known as RMC 136 that contains several similar superstars. ...

... 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 .

Some astronomers ignore low-mass stars because they aren t very bright. However, stars with initial masses between about 0.8 Msun and 8 Msun (AGB stars) play an important role as the main site of the slow neutron capture (s-)process, which produces roughly half of the elements heavier than iron. ... From this work, we will see have a better understanding of AGB nucleosynthesis, the chemical evolution of globular clusters, and the properties of helium-rich stars. ...

... 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 ...

... Observing . ... Subscriber Extras . ... Web Extras . ... Globular cluster NGC 2808, elliptical galaxy NGC 2986, and the Sextans Dwarf . ... Observing springtime deep-sky objects with a large telescope . ... Web Extra: Astronomers animate one of the largest galaxy clusters ever observed . ... At the center of the Phoenix Cluster, a large elliptical galaxy lurks where the hot gas is ejected, giving off unprecedented levels of X-rays, which have been observed by the orbiting Chandra X-ray telescope. ...