... 2008 February 10 . Abell 2218: A Galaxy Cluster Lens . ... WFPC2 , HST , NASA . Explanation: Gravity can bend light, allowing huge clusters of galaxies to act as telescopes. Almost all of the bright objects in this Hubble Space Telescope image are galaxies in the cluster known as Abell 2218. ... The cluster of galaxies Abell 2218 is itself about three billion light-years away in the northern constellation of the Dragon ( Draco ). ... About APOD | ... A service of: ASD at NASA / GSFC . ...

... Credit Copyright: ESA , NASA , J.-P. Kneib ( Caltech / Observatoire Midi-Pyrenees ) R. Ellis ( Caltech ) Explanation: Gravity can bend light, allowing whole clusters of galaxies to act as huge telescopes. Almost all of the bright objects in this just- released Hubble Space Telescope image are galaxies in the cluster known as Abell 2218. ... The cluster of galaxies Abell 2218 is itself about two billion light-years away in the northern constellation Draco . ... Abell 2218: A Galaxy Cluster Lens . ...

Astronotes Armagh Planetarium's Stellar Blog! ... Comets and Asteroids . ... Image credit:ESO/J.Emerson/VISTA. ... However others are less pessimistic and it has even been claimed that the mysterious ?Wow! signal? received in 1977 originated from the direction M55.б  Sadly, this still unexplained pulse of radio energy originated from a location rather to the northwest of M55 so I doubt if the source was this cluster (if indeed the signal was genuinely of extraterrestrial origin). ... Mysterious Wow! ...

In this gallery are many images of Low Surface Brightness Galaxies which have recently been discovered and analyzed. ... The central surface brightness of this galaxy is 24.28 . Malin 2 This galaxy is another huge disk galaxy with a scale length of 15 kpc and a redshift of 15000 km/a. The high surface brightness knot in one of its spiral arms actually has the same color, luminosity and H-alpha equivalent width as the entire Large Magellanic Cloud . ... Truly it is a Low Surface Brightness Galaxy. ...

... Radio source identifications . The Web-server of the Astronomical Institute of the St.-Petersburg University opens the experimental service on assignment of clusters data. At present only the data about radio sources in ACO clusters of galaxies are reasonably complete, while only restricted optical information is in our database. Later on, we also intend to include X-ray data and data about brightest cluster galaxies (BCG). ... ACO: radio optic ( for example, A0690 and " optic "), . ...

... Ultra-compact dwarf galaxies (UCDs): . ... UCDs are characterised by old stellar populations, are larger, brighter and more massive than the biggest Milky Way globular clusters (GCs), but at the same time significantly more compact than typical dwarf galaxies of comparable luminosity. ... UCDs are remnant nuclei of tidally stripped dwarf galaxies ( Bassino et al. ... UCDs are genuine compact dwarf galaxies formed in the smallest peaks of primordial dark matter fluctuations ( Drinkwater et al. ...

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. ...

... VLA observations and Tully-Fisher distances of gas-poor spiral galaxies in the Virgo Cluster Region . ... The HI-H2 Pressure Relation In Early-Type Galaxies . ... Tracing evolution of early-type spirals through the neutral hydrogen window . ... An Arecibo HI 21-cm Absorption Survey of Rich Abell Clusters . ... The Arecibo Ultra-Deep Survey . ... Absorption in varying galactic environments seen in HI surveys . ... Early-type galaxies with neutral hydrogen in the Virgo cluster from the ALFALFA survey ...

... These Frontier Fields will combine the power of HST with the natural gravitational telescopes of high-magnification clusters of galaxies. ... We are soliciting gravitational lensing maps for the last four Hubble Frontier Fields clusters (MACSJ0717.5+3745, MACSJ1149.5+2223, AbellS1063, and Abell 370) based upon the exceptionally deep HST FF imaging and other new ancillary data. ... For the full set of proposal instructions and requirements, see the FY16 Frontier Fields Lensing Map Call for Proposals....

... February 22, 1999 . NGC 1316: After Galaxies Collide . ... WFPC2 , HST , NASA . ... A preliminary inspection indicates that NGC 1316 is an enormous elliptical galaxy that started devouring a smaller spiral galaxy neighbor about 100 million years ago. ... Most elliptical galaxies have more and brighter globular clusters than evident in NGC 1316 . ... One hypothesis therefore holds that these globulars survive from an even earlier galaxy that was subsumed into NGC 1316. ... About APOD > . ...

... 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. ...

... 1) A new bright galaxy of the Local Group VV124 (UGC4879) is found. ... Kopylov A.I., Tikhonov N.A., Fabrika S.N., Drozdovsky I.O., Valeev A.F., MNRAS Lett, V. 387, Issue 1, L45, 2008. ... For systems of galaxies in the regions of the Hercules and Leo superclusters the dwarf-to-giant ratio of galaxies in the r-band is evaluated, and it is found that this ratio increases with increasing X-ray luminosity at log L X > 43.5 erg/s. Kopylova F.G., Kopylov A.I., Ast. ... Kopylova F.G., Kopylov A.I., Ast. ...

... Australia Telescope Compact Array . ... Compact Stellar Systems in the Fornax Cluster: Super-massive Star Clusters or Extremely Compact Dwarf Galaxies? ... We suggest that these objects are either super-massive star clusters (intra-cluster globular clusters or tidally stripped nuclei of dwarf galaxies) or a new type of low-luminosity compact elliptical dwarf (``M32-type'') galaxy. ... Keywords: galaxies: star clusters -- galaxies: dwarf -- galaxies: formation . ... Properties of the compact objects ...

... Tonight's Sky . ... Observing . ... galaxies . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... 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 . ... Our Galaxy's oldest open clusters . ... Get instant access to subscriber content on Astronomy.com! ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email...

... This paper ( Burke et al. 2003 ) describes the creation of one such catalogue - the Southern Serendipitous High-redshift Archival ROSAT Cluster (SHARC) survey - which covers an area of 17.7 deg 2 and consists of 32 clusters with redshifts between 0.05 and 0.7 and X-ray luminosities between 7 x 10 42 and 4 x 10 44 erg/s: the high-redshift subsample contains 16 clusters with = 0.3 and X-ray luminosities greater than 2 x 10 43 erg/s (luminosities are quoted for the 0.5 - 2.0 keV energy band). ... 1997 ...

Results from 6m telescope observations of globular clusters in dwarf galaxies Sharina M. We consider properties of globular clusters in dwarf galaxies observed with the multi-slit unit of the SCORPIO spectrograph at the SAO 6m telescope. ... Studying GCs in dwarf galaxies at the faintest end of the galaxy luminosity function provides valuable information for a better understanding of galaxy evolution and evolutionary connection between globular clusters and nuclei of galaxies. ...

... 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. ...

GALAXIES cenA .tiff 40 Bright Radio Galaxy M31.tiff Nikon Andromeda Galaxy (note HII regions in spiral arms) ngc6744.tiff 40 NGC 6744 a face-on spiral clouds_20d.tiff H'blad The Magellanic Clouds our nearest neighbours Lmc_7.tiff Nikon The Large Magellanic Clouds Lmc_zoom.tiff Nikon Detail of previous image smc_7.tiff Nikon The Small Magellanic Clouds smc-zoom.tiff Nikon Detail of previous image 30dor_40_BVR.tiff 40 The 30 Dor ... B [OIII] Halpha trifid.tiff 40" The Trifid Nebula. ...

... Curriculum Vitae Observations and theory of star cluster formation 22) A.K.Dambis and Yu.N.Efremov Journal for History of Astronomy, 31, 115-134, 2000 Dating Ptolemy's star catalogue through proper motions: the Hypparchan epoch 23) B.G.Elmegreen, Yu.N.Efremov, S.Larsen Astrophys. J., 535, 748 - , 2000 A young globular cluster in the galaxy NGC 6946 24) Yu.N.Efremov. ... 28) Yu.N.Efremov. ... The location of star complexes in the Galaxy was studied in papers with E.Alfaro, L.Berdnikov and T.Sitnik. ...

... 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. ...