... The overall globular cluster population is divided by gap in the metallicity function at [Fe/H]=-1.0 into two discrete groups with well-defined maxima at [Fe/H]=-1.60?0.03 dex, and -0.60?0.04 dex. ... Clusters with extremely blue horizontal branches occupy a spherical volume of radius ~ 9 kpc, have high rotational velocities ( V rot =77?33 km/s), have substantial and equal negative radial and vertical metallicity gradients, and are, on average, the oldest group (the old-halo subsystem). ...

... 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. ...

Fundamental parameters and time evolution of mass loss are investigated for post-main-sequence stars in the Galactic globular cluster 47 Tucanae (NGC 104). ... We confirm the cluster's distance as d = 4611+213 -200 pc and age as 12 ТБ 1 Gyr. Horizontal branch models appear to confirm that no more red giant branch mass loss occurs in 47 Tuc than in the more metal-poor Я? Centauri, though difficulties arise due to inconsistencies between the models. ...

... 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. ...

... The perceptron structure, on the basis of which the database is built, is defined by a number of the input and output parameters and a required accuracy. ... The output perceptron data are the expansion coefficients of the scattering matrix elements in series of the generalized spherical functions. ... As the cluster structure depends on the generation conditions the expansion coefficients were averaged over 5--7 realizations of the clusters (for N . ... is the coefficient number. ...

... Programme . ... Abstract: Globular clusters can probe the formation history of galaxies by providing evidence for the chemical evolution and major episodes of star formation in their host galaxies, by examining their kinematic signatures, as well as their structural parameters. ... The giant elliptical NGC 5128 (Centaurus A), at a mere 4 Mpc away, gives us the only opportunity to study in extensive detail the globular cluster system of a recent merger galaxy. ...

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 central velocity dispersion represents the internal motions of the stars along a column crossing the center of a galaxy or star cluster. ... The catalogue of collected velocity dispersions may be accessed in HyperLeda. vdis is the velocity dispersion given in km/s. The velocity dispersion gives to some approximation the scale for the specific kinetic energy contained in in un-ordered motions and combined with the velocity of rotation it may give an estimate of the specific kinetic energy. ...

... Dept. for Physics of Stars&Galaxies . ... Using a database view Sloan Digital Sky Survey (SDSS), containing almost a million spectra created 15,000 sample galaxies with active star formation, which is used for various studies and physical state of evolution of galaxies. ... Star clusters of the Galaxy . The project MWSC (Milky Way Star Clusters) directory using 2MASS, which includes nearly 500 million vision to the limit Ks = 15.3, analyzed more than 4,000 cluster-like objects in the galaxy. ...

... 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 . ...

... Meta Index / Home Page This section documents the parameters recognized by this task (if any). Parameter . ... Default . Constraints . columns . ... List of fully qualified column names . elements . ... Int . Number of the elements to be set. 0 means all elements from element to end of row (inclusive) . ... Number of the first element to be set. fromrow . ... Number of the first row . rows . ... Number of rows. 0 means all rows from row to end of column (inclusive) . ...

Following designations of elements/ parameters are used in AMPLE. ... mean anomaly . ... Node . ... Apart conventional orbital elements AMPLE gives possibility to calculate for each minor planet the following often used functions: . ... MOID . ... To calculate MOID user should order the name or the number of the major or minor planet through dialog. ... To calculate CT user should order the name or the number of the major or minor planet through dialog as it is proposed for MOID calculation. ...

... 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 ) . ...

The new view on the population of Galactic open clusters A.E.Piskunov1, N.V.Kharchenko2, S.RЖser3, E.Schilbach3, R.-D.Scholz4 1 2 3 4 Institute of Astronomy, Moscow, Russia Main Astronomical ... Observatory, Kiev, Ukraine Astronomisches Rechen-Institut, Heidelberg, Germany Astrophysikalisches Institut Potsdam, Germany What are open clusters and what do they teach us Groups of Population I ... Cluster complexes: OCC-1 = Gould's Belt cluster complex? ...

... A file upload element on an HTML form. ... JavaScript 1.1: added type property . ... The HTML INPUT tag, with "file" as the value of the TYPE attribute. For a given form, the JavaScript runtime engine creates appropriate FileUpload objects and puts these objects in the elements array of the corresponding Form object. ... form . ... For all FileUpload objects, the value of the type property is "file" . ... Use the value property to obtain the file name that the user typed into a FileUpload object. ...

... 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. ...

... WMAP7 -- 7 year WMAP data ( Larson at al., ... SPT -- CMB power spectrum from SPT ( Keisler et al., ... CDM -- flat Universe with cosmological constant . ... N eff 3.046 . ... WCDM -- flat Universe with dark energy . ... CDM, WMAP7+BAO+H0 +CL . CDM, WMAP7+BAO+H0+SPT +CL . ... CDM+f (1), WMAP7+SPT+BAO+H0 +CL . CDM+f (1)+N eff , WMAP7+SPT+BAO+H0 +CL . ... CDM+N eff , WMAP7+BAO+H0 +CL . ... CDM+dn/dlnk, WMAP7+BAO+H0 +CL . ... WCDM, WMAP7+SPT+BAO+H0 +CL . ... WCDM, WMAP7+SPT+BAO+H0+SNSYS +CL . ...

Teaching courses . for student of the Department of Astrophysics and Stellar Astronomy . ... Geophysics and physics of the planets (Kurt, Panteleev) . ... Close Binary Stars . ... Solar Physics . ... This is introductory course for students of the third year of education which are familiar with elementary astronomy and general physics. ... The one-year course includes theory of radiation transfer, theory of internal stellar structure with account of binary systems with compact comapnions. ...

Astronomy Picture of the Day . ... How do dying stars eject their outer layers? Stars that create elegant planetary nebulas like Henize 3-401, pictured above, are not unusual, causing speculation that, one day, our own Sun may look like this. A Star Cluster in Motion . ... A Setting Sun Trail . ... NGC 1569: Heavy Elements from a Small Galaxy . ... For the open cluster of stars NGC 6520, every day is like this. On the left of the above picture are many of NGC 6520's bright blue stars. ...

... galaxies: bulges galaxies: clusters: general galaxies: clusters: individual: . ... star formation statistics stellar content structure Cosmology ( cosmology :) cosmic background radiation ( cosmology :) cosmological parameters cosmology : miscellaneous cosmology : observations cosmology : theory ( cosmology :) dark ages, reionization, first stars ( cosmology :) dark energy ( cosmology :) dark matter ( cosmology :) diffuse radiation ( cosmology :) distance scale ( cosmology :) early Universe (...