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. ...

... 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. ...

... Kopylov, A.I., Kopylova, F.G. "Structure of galaxy groups and clusters and measurement of their masses", . ... Kopylova, F.G., Kopylov, A.I. "Peculiar motions of galaxy clusters and groups in the Hercules and Leo supercluster regions", . ... Kopylova, F.G., Kopylov, A.I. "Analysis of the properties of clusters of galaxies in the region of the Leo supercluster", . ... Kopylova, F.G., Kopylov, A.I. "Analysis of the properties of clusters of galaxies in the region of the Ursa Major supercluster", . ...

Program Number . ... Gordon Drukier, Yale University . Shooting Stars: Looking for Direct Evidence of Massive Central Black Holes in Globular Clusters . Abstract . ... Hubble Heritage Observations of Arp 148 . ... The Sloan Digital Sky Survey (SDSS) has proven a powerful tool for identifying new lens candidates, although high angular resolution HST observations are essential for confirming those candidates as genuine gravitational lensing systems (see Program GO 10886). ... Past weeks: . ...

... Science . ... Science Users Information > Science Activities > Science in Garching > Research Area: STELLAR POPULATIONS . ... Research Area: STELLAR POPULATIONS . Subject in this research area aim at understanding the stellar content of nearby star clusters and galaxies with the goal of understanding their formation and evolution history. ... Evolution of Galaxies and the ISM Stellar Populations Faculty . ... Planets and Star Formation Stellar Populations Stellar Structure and Evolution Faculty . ...

... Primordial theory review : Dick Bond . Defects and the CMB review : Andy Albrecht . ... Gravitational wave contribution to CMB anisotropies : V.B. Lukash and E.V. Mikheeva . C_l from cosmic strings : Lloyd Knox . Some aspects of CMB anisotropies induced from topological defects : Mairi Sakellariadou . ... CMB anisotropies from scaling sources : Ruth Durrer . ... SZ observations I : Sarah Church . ... Holes in the microwave sky? ... Detecting cosmic strings in the CMB : James Robinson . ...

... In 1930, Trumpler noticed that linear diameters (LD) of open clusters increase with distance (D) from the Sun. ... Since that time, the interstellar absorption has become one of the best studied factor in astrophysics, and we may hope that current OCL distance scales are free from this LD-D correlation. To verify if this is the case we have chosen several modern OCL distance scales and test them with the same clusters and the same angular diameters that Trumpler had used back in 1930. ...

... Subject and Problems of Stellar Astronomy. ... Plane of Galaxy, Methods of Its Location Determination. ... Stars Distances. ... Other Methods of Stars Distances Determination. ... Tangential Velocities, Their Determination by Self-Motions. ... Determination of Solar Apex and Spatial Velocity by Radial and Spatial Velocities of Stars. ... Features of Orientation and Parameters of Peculiar Stellar Velocities Ellipsoid. ... General and Selective Light Absorption in Galaxy. ... Darc Clouds in Galaxy. ...

... 87.1083Owen+ VIII/29 1400-MHz Survey of 1478 Abell Clusters of Galaxies (Owen+ 1982) ================================================================================ A 1400-MHz Survey of 1478 Abell Clusters of Galaxies Owen F.N., White R.A., Hilldrup K.C., Hanisch R.J. =1982AJ.. ... 0,] Major axis error 70- 71 A2 --- n_MajAxi *[ A, B, C,NR, ] Major axis note 73- 74 I2 arcmin MinAxi *? ... Note on dist-C: Ratio of the distance of the source from the cluster center to the corrected Abell cluster...

... The study of the Large-scale structure of the Universe and measurements of the Dark Energy equation of state; The exploration of the growth and cosmological evolution of supermassive Black holes in the Universe. ... In course of the all sky survey SRG will discover about 100 000 galaxy clusters and 3 million AGNs. Galaxy clusters are the largest gravitationally bounded objects in the Universe and are best explored through the study of X-ray emission from the hot intergalactic gas. ... 2016 IKI RAN ...

Today's APOD | ... Editor's choices for the most educational Astronomy Pictures of the Day about globular clusters: . ... Explanation: Globular clusters once ruled the Milky Way . Back in the old days , back when our Galaxy first formed, perhaps thousands of globular clusters roamed our Galaxy . ... APOD: 2002 July 30 - A Star Cluster in Motion . ... Globular star clusters normally roam the halo of the Milky Way, ancient relics of our galaxy's formative years. ... Index | ... About APOD | ...

... Commission 37: Star Clusters and Associations . Home Page . Commission 37 of the International Astronomical Union deals with all aspects of Globular Cluster, Open Cluster, and Stellar Associations research. With Commission 33 it forms Division VII of the IAU. Commission Structure . ... IAU Home Page . Open Clusters Database (maintained by J.-C. Mermilliod ) . Catalogue of Milky Way Globular Cluster Parameters (maintained by W. E. Harris ) . ...

. 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 .

... 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]. ...

... 10.08.2006 . ... CXC , NASA Explanation: If you had x-ray vision , the central regions of our Galaxy would not be hidden from view by cosmic dust clouds. ... Pleasing to look at, the gorgeous false-color representation of x-ray data from the Chandra Observatory shows high energies in blue, medium in green, and low energy x-rays in red. ... It reveals massive, x-ray emitting star clusters in a crowded environment. ... Publications with keywords: X-ray . Publications with words: X-ray . ...

... Chandra Observation of DEEP2 Galaxy Groups and Clusters . ... Monday: 'Normal' Galaxies, Tuesday: Cluster Formation and Evolution . ... Statistics of galaxy groups in ultradeep XMM surveys. ... What can multiwavelength observations tell about cluster/group formation as well as galaxy evolution? ... I will present results from a Chandra study of eight low-redshift clusters that has systematically measured the AGN fraction in clusters and describe their spatial, kinematic, and host galaxy...

... 2000, ApJ, 537, L49 . ... F. Palla . Invited Talk at the IAU Symposium 200 "The formation of binary stars" eds. R.D. Mathieu and H. Zinnecker (ASP Conf. Ser.) in press . Optical follow-up of ROSAT discovered candidate members of the open cluster Coma Berenices . ... 2000, A , in press . ... 2000, ApJ, in press . ... 2000, ApJ, in press (Sept. ... 2000, ApJ Lett., in press . ... Click to examine publications from other years . ... Star Formation Group . ... Arcetri Home Page . ...

... ATNF Home . About ATNF . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . ... Mopra radio telescope . ... The Hydra and Antlia clusters are not isolated clusters, but part of a filamentary structure which can be traced from Hydra through Antlia ( cf. ... Rich massive clusters generally are strong X-ray emitters and were identified early on with the X-ray satellites (Einstein, HEAO, Uhuru). ...

. This image shows two of the galaxy clusters observed by NASA's Wide-field Infrared Survey Explorer (WISE) and Spitzer Space Telescope missions. Galaxy clusters are among the most massive structures in the universe. The central and largest galaxy in each grouping, called the brightest cluster galaxy (BCG), is seen at the center of each image. // NASA/JPL-Caltech/SDSS/NOAO

... 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 . ...