... 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. ...

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 . ...

... Our resulting sample of ELGs presented in Tables 2 and 3 is not artificially biased to any specific type of galaxies. ... Since we are looking for selection of a sample of Case BCGs, it is interesting to examine how the detected BCGs are connected with Case emission-line codes. ... Altogether BCGs comprise about 60 % of all Case ELGs which display emission lines in our spectra, or about 44 % of all Case galaxies with some emission-line code. ... Among those with the code ``w'' about 40 % are BCGs. ...

. Distribution of Supernovae according to their parent galaxies' recession velocity. This graph shows the distribution of SNe according to the recession velocity of their parent galaxies. This graph is kept up to date till SN 2000ek . Along X-axis there are all velocity bands so that you have to read in this way: for example, the band on the graph marked as 2000 takes in all parent galaxies' recession velocities faster than 1000 until 2000 Km/sec.

A Test of Galaxy Evolutionary Models Via Angular Sizes M. Im S. Casertano, R. E. Griffiths, & K. U. Ratnatunga (The Johns Hopkins University) The relationship between angular size, magnitude, and redshift of faint galaxies is explored as a potential tool to distinguish between different galaxy evolutionary models. ... The mild lumi­ nosity evolution model predicts more luminous galaxies of large angular size at high redshift, as does a standard no evolution model. ... 25) with redshift higher than z ? ...

Gerhardt Meurer (Johns Hopkins University) . The accompanying picture shows NGC 2915, which Australian, Canadian, and American astronomers have shown to be the darkest known disk galaxy. ... The team of astronomers, lead by Gerhardt Meurer at Johns Hopkins University, analyzed the rotation of the galaxy and showed that NGC 2915 is composed mostly of "dark matter". Dark matter is extremely difficult to detect since it does not emit any radiation. ... Gerhardt R. Meurer . ...

... 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. ...

... 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 . ...

BSc thesis "Metallicity Gradients of Elliptical Galaxies", 1997, Univ. of Tokyo . MSc thesis "Low-Metallicity Inhibition of Type Ia Supernovae and Galactic and Cosmic Chemical Evolution", 1999, Univ. of Tokyo . PhD thesis "Formation and Chemodynamical Evolution of Galaxies", 2002, Univ. of Tokyo . ... Cosmic SFRs, chemical evolution, mass-dependent galactic winds, and the mass-metallicity relation of galaxies are reproduced (Kobayashi, Springel, White 06). ... What are dwarf galaxies? ...

... According to the most popular cosmological paradigm, the greater part of the galaxy mass is accumulated in the dark matter halo. ... The polar ring galaxies (PRGs) reveal external rings or disks of gas, dust and stars rotating in a plane roughly perpendicular to the disk of the central galaxy. ... The shape of the dark halo in the model was chosen so as to achieve the best fit to the observed rotation of both galaxies themselves and their polar rings. ... The SPRC-7 galaxy. ...

... 05/09/2013 Galaxy Evolution over Five Decades - Cambridge 2013 Nuclear activity and environment Effect of environment on AGN is not completely clear yet. ... 05/09/2013 Galaxy Evolution over Five Decades - Cambridge 2013 Effect of the mass Mass slices ­ optical and radio AGN overall interaction one-on-one interaction relative location 05/09/2013 Galaxy Evolution over Five Decades - Cambridge 2013 Stratified study Stratifed study that considers several strata of mass. ...

Do LIRGs follow the Tully-Fisher relation? ... For a small we can say majority of investigate i Conclusion number of galaxies in our sample, that the T-F relation holds. ... The purpose of this research was to study the LIRGs (Luminous Infrared Galaxies) and see if they follow the Tully-Fisher relation. The LIRGs are different to normal galaxies in the fact that they emit 90% of their light in infrared. ... The faster the galaxy rotates, the wider is the emission line in velocity. ...

... High redshift radio galaxies . ... Verkhodanov O.V., Kopylov A.I., Zhelenkova O.P., Verkhodanova N.V., Chernenkov V.N., Parijskij Yu.N., Soboleva N.S., Temirova A.V. 2000. ... Verkhodanov O.V., Kopylov A.I., Parijskij Yu.N., Soboleva N.S., Temirova A.V. "Color ages of parent galaxies of high redshift radio sources", in Proc. XV Conf. on "Aktualnye problemy vnegalakticheskoi astronomii" ("Current Problems of Extragalactic Astronomy"), Pushchino, May 25--29, 1998, printed in Pushchino Sci. ...

... 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 can investigate projection of this distribution onto the celestial sphere in two ways: in terms of lines of constant SN frequencies per one square degree for all galaxies from the sample (Figure 36 ), and in terms of constant GW amplitudes at a given SN frequency per square degree (Figure 44 ). ... Figure 45: The sky distribution of the total supernova frequency from nearby galaxies in terms of lines of equal frequencies per square degree. ...

... 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. ...

There are still many open questions on galaxy formation and evolution, such as e.g. the predominance of hierarchical or monolithic processes in the galaxy formation or the temporal evolution of disk metallicity gradients. ... Chemical abundances of stellar populations of different ages are essential to constrain the past history of nearby galaxies, both in terms of their past metal contents and of SFHs. ...

... Cross-shaped galaxy ZGC 2315+03 (Fig.1) has been described by Zwicky (1971) as ``post-eruptive or the result of the crossing of a compact galaxy through an edge-on spiral'' . This object was included in the Polar-Ring Catalog (C-71) by Whitmore et al. (1990) as a possible candidate for Polar-Ring Galaxies (PRG). ... One of them is galaxy 'disk' and the other is 'polar-ring'. ... The facts against the polar-ring nature of ZGC 2315+03 can be summarized as follows: . ...

... Size of the Solar System Compared to our Galaxy . Mentally construct a model of our place in the Milky Way Galaxy and the distribution of stars using your hand and some birdseed. ... Using a strip of paper, construct a quick scale model of the distances between the orbits of the planets, the Asteroid Belt, and Pluto as part of the Kuiper Belt. Sharing the Universe is based upon work supported by the Informal Education Division of the National Science Foundation under Grant no DRL-0638873. ...

An image of the grand design of spiral galaxy M100 obtained with NASA's Hubble Space Telescope resolves individual stars within the majestic spiral arms. ... Hubble has the ability to resolve individual stars in other galaxies and measure accurately the light from very faint stars. This makes space telescope invaluable for identifying a rare class of pulsating stars, called Cepheid Variable stars embedded within M100's spiral arms. ... 617) 495-7062 . Fax: (617) 495-7356 . ...