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. ...

... The measurements extend to a lower 1.5 GHz limit of 1.0 mJy and comprise a complete sample with 1.5-GHz flux density 2.5 S1.5 J/AuJPh/47/145 VLA Survey of Rich Clusters of Galaxies II (Slee+, 1994) J/AuJPh/49/977 VLA Survey of Rich Clusters of Galaxies III (Slee+, 1996) ================================================================================ A VLA Survey of Rich Clusters of Galaxies II. ... Note (3): An elliptical Gaussian was fitted to the source. ...

... Editor's choices for the most educational Astronomy Pictures of the Day about clusters of galaxies: . APOD: 2006 March 21 - The Coma Cluster of Galaxies . ... APOD: 2005 November 22 - A Galactic Collision in Cluster Abell 1185 . ... A prominent example occurs on the left of the above image of the rich cluster of galaxies Abell 1185. ... Recent observations of Abell 1185 have found unusual globular clusters of stars that appear to belong only to the galaxy cluster and not to any individual galaxy. ...

... Science . ... Science Users Information > Science Activities > PhD Thesis Topics offered by ESO Faculty Members > Thesis Topic: Studying the first galaxy clusters with ALMA . ... ALMA will provide a major leap forward in our capabilities of studying the high-redshift universe, especially the first galaxies. ... These first galaxies are also found to cluster relatively strongly, and are expected to form proto-clusters, later growing to be the fully-formed galaxy clusters we see in the local Universe....

... 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]. ...

... Staff . ... Galaxies, AGN, Cosmology . ... A new survey of X-ray clusters of galaxies with the Swift-X-ray Telescope . ... In this framework, an international collaboration between INAF-OAA, INAF-Brera, INAF-OATs, the University for Science and Technology of China-Hefei, the University of Ferrara, and the University of Massachusetts-Amherst, is undertaking a new cluster survey using an X-ray facility that was never exploited before for this goal: the X-ray Telescope (XRT) onboard the Swift satellite...

... Abell 2142: Clash of the Galaxy Clusters . ... Credit Copyright: Maxim Markevitch ( CfA ), ACIS , SAO , CXC , Chandra , NASA Explanation: Over the course of billions of years, whole clusters of galaxies merge. Above is an X-ray image of Abell 2142 , the result of the collision of two huge clusters of galaxies, and one of the most massive objects known in the universe. ... Publications with keywords: cluster of galaxies . Publications with words: cluster of galaxies . ...

This site provides on-line access to publications, figures, and data tables related to an extensive multi-wavelength observational program to study distant galaxy clusters. ... Lori Lubin, Bev Oke, and Marc Postman have been studying a sample of 9 distant clusters (some taken from the PDCS) using the Keck 10m telescope, the HST, and the KPNO 4m (for IR imaging). ... A Study of Nine High-Redshift Clusters of Galaxies: I. The Survey, . ... A Study of Nine High-Redshift Clusters of Galaxies: II. ...

... 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. ...

. A "radio phoenix" has been discovered using X-ray, radio, and optical data. This system contains the collision of two galaxy clusters located about 1.6 billion light years from Earth. The collision re-energized a regeneration of vast clouds of high-energy particles that primarily radiate at radio frequencies. Understanding how galaxy clusters grow over time, including through collisions, is important for cosmology. X-ray: NASA/CXC/Univ of Hamburg/F. de Gasperin et al; Optical: SDSS; Radio: NRAO/VLA

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. ...

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! ...

... Posts tagged ?clusters? Apr 27th, 2008| 11:29 am | ... The last paper in the list discusses MCMC for time series analysis, applied to sunspot data. ... ArXiv] 4th week, Apr. ... ArXiv] 3rd week, Apr. ... Entries RSS . ... Algorithms arXiv Astro Bad AstroStat Bayesian CHASC Cross-Cultural Data Processing Fitting Frequentist Galaxies gamma-ray High-Energy Imaging Jargon Job Languages MC MCMC Meta Methods Misc News Nuggets Objects Optical Physics Quotes Spectral Stars Stat Timing Uncertainty X-ray . ...

... 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 . ...

... 1st Announcement IAU Symposium 312 Star Clusters and Black Holes Across Cosmic Time, Beijing, China, Aug. 25-29, 2014 . ... SUBJECT: 1st Announcement IAU Symposium 312 Star Clusters and Black Holes Across Cosmic Time, Beijing, China, Aug. 25-29, 2014 . ... which will be held in Beijing, P.R. China, from August 25-29, 2014, hosted by Chinese Academy of Sciences . ... China), . ... 1st Announcement IAU Symposium 312 Star Clusters and Black Holes Across Cosmic Time, Beijing, China, Aug. ...

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 . ...

Find Similar Abstracts . ... Intergalactic gas in galactic clusters, the microwave background radiation and cosmology . ... The types of information that can be obtained from astrophysical studies of the microwave background in the direction of galactic clusters and from radio observations of clusters are examined. ... Use: Authors Title Abstract Text Text Query with Keywords Return: Query Results Query Form Database: Astronomy Instrumentation Physics and Geophysics ABSTRACT QUERY USER FEEDBACK HELP ...

... 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. ...

Polarization signatures of clusters in the microwave background Anthony Challinor University of Cambridge, U.K. Galaxy clusters along the line of sight leave an imprint in the po- larization of the cosmic microwave background radiation (CMB). ... We also discuss the prospects of detecting such e ects, and outline some possibili- ties for using cluster polarization as a probe of cluster physics and cosmology. ...

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. ...