... 2.3 Establishing the Extragalactic Distance Scale . ... 2.3.2 The Second Rung: Distances to stellar clusters . ... 2.3.4 Distances to Local Group Galaxies . ... The Luminosity Function of Planetary Nebulae . ... 3.2.2 Clusters of Galaxies . ... 4.2 Evidence for Dark Matter as a Function of Scale Size . ... 4.3 Other Dark Matter Indicators for Galaxies . ... What is the nature of the large-scale distribution of matter in the universe as traced by the three-dimensional galaxy distribution? ...

... 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. ...

... The Hydra Cluster of Galaxies . ... Listed as Abell 1060, the Hydra Cluster contains well over 100 bright galaxies. ... All of the bright extended images in the above picture are galaxies in the Hydra Cluster with the exception of unrelated diffraction crosses centered on bright stars. ... In fact, the Hydra cluster is thought to be part of the Hydra-Centaurus Supercluster of galaxies . ... Publications with keywords: cluster of galaxies - Hydra . ... Abell 2218: A Galaxy Cluster Lens . ...

... 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. ...

... We have simulated the observations of a very distant cluster of galaxies at high redshift. ... The simulations are made for the HST instruments FOC, WFPC II, and the Advanced Camera, and for an 8-m telescope on the ground equipped with adaptive optics. ... A comparison of the fields of view of post-COSTAR HST imaging instruments with the Advanced Camera (AC) and the ground-based adaptive optics camera (AO) is shown in Fig. 1 superimposed on the noise-free cluster simulation. ...

... 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. ...

... 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. ...

... About ATMoB . ... The Observing Committee is starting an Observing Awards Program to promote observing among the membership of the Amateur Telescope Makers of Boston. ... Participant must be a current member of the Amateur Telescope Makers of Boston . ... To qualify for your Observing Award Certificate, turn in your worksheet and drawings to an ATMoB Observing Committee member or observing@atmob.org . ... This Excel sheet has useful macros. ... Copyright (c) Amateur Telescope Makers of Boston, Inc. ...

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. ...

... Scaling relations of galaxies: . ... 2007) . ... This research is now being extended to other clusters such as Hydra and Centaurus, by Ingo Misgeld . ... 2007 , Misgeld et al. 2008 and 2009 ) support a picture where the scaling relations of dwarf galaxies are shaped more by internal than external agents, given that colour-magnitude and magnitude-surface brightness relations agree quite well between the low-density Local Group environment and dense clusters like Fornax and Hydra. Misgeld et al. ...

... Press Release Images . Individual Images . ... The right-hand image shows Hubble's close-up view of the galaxy's core, taken in December 1995 by the Wide Field and Planetary Camera 2. The bluish-purple clumps that form the ring are the clusters of infant stars. Two dark, wispy lanes of dust and a pair of blue spiral arms are just outside the star-forming ring. ... The gas is trapped inside the ring through the stars' gravitational attraction. ... Amazing Space | ...

Rastorguev А.S. "Astronomical Distances" (Lecture course for postgraduates, 2009-2016) . Part 1. ... Trigonometric parallaxes of stars. Moving clusters distances. ... Photometric distances: general approach. Normal stars as "standard candles". ... Main Sequence fitting or distance scale of star clusters. ... Moving photospheres technique. Cepheid distance scale and P-L relations. RR Lyrae distance scale. ... Globular clusters luminosity function. ...

Astronotes Armagh Planetarium's Stellar Blog! ... Stars . ... Starbursts are short-lived events, stars are forming so quickly that the reservoirs of interstellar gas from which stars are coalescing would be used up on a timescale much shorter than the age of the galaxy . ... Strong stellar winds from giant new stars in the starburst region combine with the blasts of supernovae to push a mighty flood of extremely hot gas, a ?superwind? from the galaxy thousands of light years into intergalactic space. ...

Elliptical galaxies Elliptical galaxies Rough subdivision · Normal ellipticals. ... Dwarf ellipticals (dE's). ... E dE BCD dSph 1013 - 1014 108 - 1013 107 - 109 109 107 - 108 300-1000 1-200 1-10 3 0.1­0.5 100 10­100 1­10 0.1­10 5­100 Elliptical galaxies Shapes of elliptical galaxies Elliptical galaxies Shapes of elliptical galaxies Elliptical galaxies Shapes of elliptical galaxies Elliptical galaxies Shapes of elliptical galaxies Elliptical galaxies ...

. F IGURE . 5. Relation between metallicity and (a) cluster Galactocentric distance and (b) distance from the Galactic plane. The straight lines are the rms regression fits for the thick-disk, entire Galaxy, and halo from top to bottom, respectively. The slopes of the lines yield the corresponding metallicity gradients. discussion in the text | previous figure | next figure .

The radial distribution of metallicity of star-forming galaxies in a galaxy cluster can inform us about the mass assembly and enrichment history of the galaxy cluster. ... Both galaxy clusters are cool-core clusters at redshift z т?? ... The gas-phase metallicity of star- forming galaxies in MACS1115+01 exhibit anti-correlation with projected distance т??0.15 ТБ 0.08 dex/Mpc, whereas the radial metallicity distribution of RXJ1532+30 is statistically flat (т??0.09 ТБ 0.12 dex/Mpc). ...

... Session 1 - Stars, star formation, stellar populations and planets . 9.20 10.00 . ... HST Spectroscopy of the Hottest White Dwarfs . ... Coffee break . ... Lunch break . ... A (long) look at neutron stars with HST . ... Session 2 - Nearby galaxies, bulges, spheroids, galaxy formation . ... New HST/ACS Insights into the Evolution of Star-Forming Dwarf Galaxies with Extreme Properties of Cosmological Relevance . ... Deriving properties of Lyman-break galaxies at z~3-5 using HST/VLT/Spitzer data . ...

The fundamental properties of early-type galaxies in the Coma Cluster S.A.W. Moore et al. University of Durham, U.K. Co-authors: Lucey, J.R.; Colless, M.; Kuntschner, H.; Bower, R.; Davies, R.L. Early-type galaxies in clusters exhibit remarkably tight correlations between their global properties, e.g. the colour- magnitude relation, the Mg2 - relation and the Fundamental Plane. ... In addition, these data provide a baseline for evolutionary studies of distant clusters. ...

... Bad Astronomy . ... Bitesize Astronomy . ... The last step encompassed them all with galaxies , and how we discovered that the Milky Way was not the entire Universe. ... And just like those star clusters, there are different kinds of galaxy clusters. ... There are vast clusters of clusters, called superclusters, which contains hundreds of thousands or even millions of galaxies. ... Our own Galaxy has 400 billion stars in it, yet there are clusters out there with millions of galaxies like our own. ...

... D. J. Burke and J. Patrick Henry . The Astrophysical Journal, submitted. ... S. Brough, W. J. Couch, C. A. Collins, T. Jarrett, D. J. Burke , R. G. Mann . ... D. A. Wake, C. A. Collins, R. C. Nichol, L. R. Jones, D. J. Burke . ... R. Sadat, A. Blanchard, S. C. Vauclair, D. H. Lumb, J. Bartlett, A. K. Romer, J.-P. Bernard, M. Boer, P. Marty, J. Nevalainen, D. J. Burke , C. A. Collins, R. C. Nichol, . ... S. Majerowicz, D. M. Neumann, A. K. Romer, R. C. Nichol, D. J. Burke , C. A. Collins . ...