... Abell 2744: Pandoras Cluster of Galaxies . ... Credit Copyright: NASA , ESA , J. Merten ( ITA , AOB ), D. Coe ( STScI ) Explanation: Why is this cluster of galaxies so jumbled? Far from a smooth distribution, Abell 2744 not only has knots of galaxies, but the X-ray emitting hot gas (colored red) in the cluster appears distributed differently than the dark matter . ... Publications with keywords: galaxy cluster - dark matter - hot gas . ... The Hydra Cluster of Galaxies . ...

... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2011 June 29 . Abell 2744: Pandora's Cluster of Galaxies . Image Credit: NASA , ESA , J. Merten ( ITA , AOB ), D. Coe ( STScI ) . ... Far from a smooth distribution, Abell 2744 not only has knots of galaxies, but the X-ray emitting hot gas (colored red) in the cluster appears distributed differently than the dark matter . ... About APOD | ...

M1 image More About M1 Nice Color Picture . ... M16 image More About M16 HST image . ... M31 image More About M31 Nice Color Picture . ... M42 image ; M43 image More About M42/43 Nice Color CCD Picture . M51 image More About M51 Color Image of M51 M51 Supernova . M57 image More About M57 Nice Color CCD Picture Very Deep M57 Image . ... M81 image More About M81 M81 Supernova Ultraviolet Image of M81 More about Ultraviolet Imaging . M82 image More About M82 M82 False Color M82 True Color . ...

... Bad Astronomy . ... Bitesize Astronomy . ... Last week's Snack talked about how black holes can affect the environment around them in such a way as to be very bright . ... It's a common misconception that black holes always have matter swirling into them. ... As this matter gets closer and closer to the black hole it piles up and a large, fairly flat disk forms. This is called the accretion disk , because matter from this disk accretes (that is, falls in) on the black hole. ... 2008 Phil Plait. ...

... The colors indicate the relative motions of galaxies with accurately measured distances, with shades of green and blue indicating motions toward us and shades of yellow to red indicating motions away from us. Our nearest neighbors have only small relative motions (represented by yellows and greens), as seen best in the exploded view of the right panel. We, along with all these nearest neighbors, are moving together toward the lower right corner of the figures. ...

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). ...

... ftp://www.kusastro.kyoto-u.ac.jp/pub/cgmw/ : This catalog, giving about 7000 galaxies behind the Milky Way between l = 210 degrees and 250 degrees, represents a systematic search for galaxies by means of 32 film copies of the UK Schmidt Southern Infrared Atlas on the Milky Way covering about 900 square degrees. ... Japan, Vol. ... This will be distributed upon request from Astronomical Data Analysis Center of the National Astronomical Observatory of Japan and other astronomical data centers. ...

... Why Lyman Limit Systems (a.k.a LLSs)? ... 2014; MF et al. 2015 in prep Method #2: LLS autocorrelation The basic idea behind the experiment is to probe the correlation length of LLSs , which should correspond to the size of halos Dark matter halos NH N H Projected Separation NHI UVB Redshift Method #2: LLS autocorrelation The basic idea behind the experiment is to probe the correlation length of LLSs , which should correspond to the size of ...

... 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 observations include broad band optical imaging and spectroscopy with the Low Resolution Imaging Spectrograph at the 10 meter W. M. Keck Observatory telescope; K-band imaging with IRIM at the 4 meter Kitt Peak National Observatory telescope; and deep, high angular resolution imaging with the WFPC2 onboard the Hubble Space Telescope. ... 1 )Palomar Observatory, California Institute of Technology, Pasadena, CA 91125 . ... huizinga@stsci.edu . ...

... Neutral and Ionised Hydrogen in NGC 4214 V. J. McIntyre1,2 1 2 Physics Department, University of Wollongong, Wollongong, NSW 2522, Australia Astrophysics Department, University of Sydney, NSW 2006, Australia vjm@physics.usyd.edu.au Abstract: It is not clear at present how the diffuse ionised gas (DIG) component in galaxies is ionised. ... How porous the ISM must be depends on the (unknown) location of the ionised emission relative to the disk. ... 1996). ... Local H I surface density is 2в1021 cm-3 ...

... This represents the first HI selected sample covering the core and the outskirts of a local cluster of galaxies. ... Optically selected samples miss a considerable number of low luminosity, low surface brightness galaxies underestimating by almost a factor 2 the number of HI rich galaxies present in the cluster volume. ... Right: The g band luminosity function for galaxies in the A1367 volume as obtained from the optically (circles) and HI (histogram) selected sample. ...

... Here some data observed on the 6m telescope with IFP installed in the OLD focal reducer are presented. ... Mkn 3: velocity field . ... NGC 5252: [OIII] image . ... NGC 5252 was observed 23 Feb. 1998 in the [OIII]5007 emission line with CCD TK1024 as detector. ... We observed the ionized gas velocity fields of the spiral galaxies with two purpose. ... Restored velocity field of NGC 157 in the reference frame rotating with the pattern speed overlaid on the Ha image of the galaxy . ... NGC 4100 . ...

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... The obtained results lead to the following conclusions: a) the heavy element enrichment had taken place in the Galaxy in a few bursts of its activity rether than in a continuons manner; b) these bursts occured during the callapse of the early Galaxy; c) the star formation had been inhibited in the time of the bursts; d) the metal enrichment did not proceed in the periods of star formation, between these bursts of activity. ...

Title: A Dark-Matter Spike at the Galactic Center? Authors: Piero Ullio , HongSheng Zhao , Marc Kamionkowski . ... Title: The Galaxy Environment of Quasars in the Clowes-Campusano Large Quasar Group at z~1.3 . ... Title: The Galaxy Environment of a Quasar at z=1.226: A Possible Cluster Merger . ... 16 matches for the search pattern galaxy environment . The URL for this page is: http://xxx.itep.ru/find/astro-ph/1/galaxy+environment/0/1/0/past,all/0/0 www-admin@xxx.lanl.gov ...

... Next: Cheating Poisson: A Up: Statistical Analysis Previous: Spatial Models and . ... The spatial distribution of stars in the Local Group dwarf irregular galaxy NGC 6822 has been studied, using recent positions and deep photometry for about 15,000 stars in the galaxy. Based on photometrical data, OB stars and red stars could be studied separately. Spatial statistical tools have been applied to the analysis of the spatial structure. ... Figure: Model selection by the aid of CAIC . ...

Hot subdwarfs are hots stars with masses somewhat less than that of the Sun. ... They are known as sdB stars because their spectra are dominated by hydrogen lines. ... Normally, a red giant will switch on core helium burning without losingthe layers of hydrogen around the helium core. sdOB stars are related to sdB stars, possibly being the sdB stars which have completed core helium burning and are evolving to become white dwarfs. ... Such stars are known as PG1159 stars and DO white dwarfs. ...

Astronotes Armagh Planetarium's Stellar Blog! ... Our Galaxy . ... Other Galaxies . ... Telescopes and Observatories . ... Everyone loves stunning pictures of spiral galaxies,€а I have said this before and will no doubt say it again. The folks at the European Southern Observatory (ESO) know this too, and their latest public image release is a bumper set of serenely spinning spirals. ... Tweets that mention Six glorious spiral galaxies seen by the European Southern Observatory. ...

Next: Massive X-ray Binaries Up: No Title Previous: X-ray Galactic Sources and . Table  7 represents the full matrix of stages of binary stars in a model spiral galaxy with the total mass of matter in stars of for (flat spectrum), and Lyne and Lorimer's distribution for kick velocities (equation 7.4.2 )   with km s (which gives the transverse velocity distribution for modeled pulsars best-fitting Lyne and Lorimer (1994)[ 132 ] data; Figure  24 ). ...