We explore variations in dust emission within the edge-on Sd spiral galaxy NGC 4631 using 3.6-160 ЮМm Spitzer Space Telescope data and 450-850 ЮМm JCMT data with the goals of understanding the relation between PAHs and dust emission, studying the variations in the colors of the dust emission, and searching for possible excess submillimeter emission compared to what is expected from dust models extrapolated from far-infrared wavelengths. ...

... The Hydra Cluster of Galaxies . ... Most of a cluster's mass , however, appears to be in a form too dark to see , as analyses of the distribution of X-ray light , gravitational lensing , and internal motions indicate. ... The Hydra Cluster of Galaxies, named for its home constellation , spans about ten million light years . ... Publications with keywords: Hydra - cluster of galaxies . Publications with words: Hydra - cluster of galaxies . ... Illusion and Evolution in Galaxy Cluster Abell 2667 . ...

... The sample of the Local Volume galaxies (distance smaller than 10 Mpc) gives a unique opportunity to study the properties of galaxies including the weakest objects: the absolute magnitude M B -10 and the virial mass M vir 10 9 M x263C;. ... Luminosity function of the Local Volume galaxies. ... The luminosity functions for galaxies are presented: red dashed line - from the 2dFGRS survey (Norberg et al. 2002); blue dash-dotted line - from the SDSS survey (Blanton et al. ...

... 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? ...

... 2004 January 20 . Unexpected Galaxy String in the Early Universe . ... Explanation: How could such a long string of galaxies form so early in the universe? Several new measurements of galaxies and clusters in the early universe are reporting structures involving galaxies and clusters that are larger than expected with the new standard "dark-energy" cosmology . The controversy centers on the inability of a dark-energy dominated universe to create such large structures. ... About APOD | ...

The very metal-poor local dwarf galaxies - the analogs of primordial galaxies in young Universe . ... The goal of this project is the study of the properties of the local eXtremely Metal-Deficient (XMD) dwarf galaxies. ... S.A. Pustilnik, J.-M. Martin . ... Pustilnik S.A. "Dark galaxies" and local very metal-poor gas-rich galaxies: possible interrelations, in: Dark Galaxies and Lost Baryons, Edited by J.Davies and M.Disney, Proceedings of IAU Symposium No. 244, held 25-30 June, 2007 in Cardiff, UK. ...

... 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...

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). ...

... QSO spectra in the ROSAT band are steeper than the background at harder energies, and furthermore at fluxes below 1E-14 ergs/(s cmќ) the quasar source counts flatten off and are replaced by more numerous populations of relatively low red-shift objects, apparently Narrow Emission Line Galaxies (NELG). ... We extracted the luminosity function from ROSAT Deep Survey results, and extrapolated by a factor of 2 - 3 to account for changes expected in the harder XMM band. ...

... Visible Distribution of Galaxies. ... Features of Elliptical, Lens-Shaped, Spiral and Irregular Galaxies. Galaxies with Bar. ... Distribution of Surface Brightness of Surface and Spiral Galaxies. ... Color Characteristics of Galaxies. ... Methods of Galaxies' Mass Determination. ... Hidden Mass of Spiral Galaxies. ... Features of Dark Matter Distribution in E and SO Galaxies. ... The Whole Number of Galaxies and Their Density by the Results of Observation on the 'Hubble' Space Telescope. ...

... ESO, the European Southern Observatory . ... ESO's Governing Bodies . ... Green ESO . ... This artistтАЩs impression shows the Milky Way galaxy. The blue halo of material surrounding the galaxy indicates the expected distribution of the mysterious dark matter, which was first introduced by astronomers to explain the rotation properties of the galaxy and is now also an essential ingredient in current theories of the formation and evolution of galaxies. ... Dark Matter , Milky Way . ... Milky Way . ...

... 2000 . ... Abstract: I present the distribution of the brightest galaxies in the southern sky as obtained from the H I Parkes All-Sky Survey (HIPASS). ... A histogram of the systemic velocities of the brightest HIPASS galaxies is shown in Fig. ... It peaks, as expected, in the interval 800 to 2000 km/s. No bright galaxies were found with systemic velocities of less than -350 or more than 5500 km/s. Figure 2: Histogram of the H I systemic velocities of the brightest galaxies obtained from HIPASS. ...

... Nearest large grouping of galaxies. ... Luminosity function verse the HI mass function. Isolated HI clouds - the efficiency of galaxy (star) formation. Data Part of HIJASS - 4 beams with 12' resolution, 64 MHz bandpass with 1024 channels (12 km s-1). ... Rms noise of 4 mJy beam-1 compared to HIJASS and HIPASS standard surveys of 13 mJy beam-1. ... Comparison of Virgo HIJASS and HIPASS data Jodrell pointed observations Optical data HI mass function Distribution of velocities Conclusions 1. ...

... HI mass fractions Comparison samples HeViCS bright galaxy Catalogue(BGC) Davies+2012 Average scaling relations for HI-normal and extremely HI-deficient galaxies in H3 survey (Gavazzii+ 2013 ) Dwarf galaxy survey (DGS) Madden+ 2013 KINGFISH Kennicutt 2011 Specific star formation rates Schiminovich +2007 Comparison samples HeViCS bright galaxy Catalogue(BGC) Davies+2012 Dwarf galaxy survey (DGS) Madden+ 2013 KINGFISH Kennicutt 2011 Dust ...

... Gravitational wave search provides insights into galaxy evolution and mergers . ... galaxies . ... Globular cluster NGC 2808, elliptical galaxy NGC 2986, and the Sextans Dwarf . ... Open cluster NGC 2818, spiral galaxy NGC 2964, and spiral galaxy NGC 2976 . ... What are typical star-to-star distances in globular clusters compared to stellar distances in our region of the galaxy? ... RELATED TOPICS: GLOBULAR CLUSTERS . ... Get instant access to subscriber content on Astronomy.com! ...

... We compare our results with the GRANAT X-ray observations of the Galactic center (Churazov et al. ... It is instructive to compare our results for the Galactic center starburst with what might be expected for a continuous star formation, with the average rate characteristic for the whole Galaxy. For this continuous star formation model, we would expect to observe in the region of around the Galactic center about 10% of the total number of X-ray sources in the Galaxy. ...

The LCDM paradigm: successes and challenges on scales of galaxies Anatoly Klypin (NMSU) LCDM · · · · DM profiles, concentrations, .. Clustering of galaxies: P(k) and correlation functions Satellites: abundance, number-density profiles Galaxies and Dark Matter: abundances Dwarfs. ... Springel et al 2008. ... Klypin et al 2010. ... Observations - LCDM: just enough Magellanic Clouds Observations LCDM Vmax > 50 km/s Busha et al 2010 Dark matter profiles: standard LCDM Aquarius simulation. ...

... Over the first 4 years, its X-ray telescopes eROSITA and ART-XC will survey the whole sky with a record sensitivity in the 0.5-10 keV energy band. ... The goal of the second international Spectrum-RG conference is to discuss the different scientific topics addressed by the mission, synergies with surveys at other wavelengths, and requirements to follow-up observations.Contributed talks and poster presentations are invited on the topics related to the SRG science goals. ... Active galactic nuclei . ...

... Right: cold gas traced by [CII] emission (red) accreting onto a primeval galaxy (green) at z=7.1 ( Maiolino et al. 2015 ) (image credit: ALMA Press Release ) . ... 2010 , Cicone, Maiolino et al. ... 2012 , Cicone, Maiolino et al. ... Right: observed distribution of the average stellar metallicities of passive and star forming galaxies in the local universe, supporting starvation/strangulation as primary quenching mechanism in low/intermediate mass galaxies ( Peng, Maiolino, Cochrane 2015 ). ...

Mercury Summer 2011 Table of Contents . ... A Hubble Space Telescope view of a segment of the Coma Cluster of galaxies, one of the densest known galaxy collections in the universe. ... In 1998, competing teams of astronomers were forced to come to grips with increasingly convincing observations that the expansion of the universe was accelerating , rather than decelerating (as they expected). ... Its discovery resulted directly from measurements of the distances to remote galaxies. ...