... One of these two bright sky objects is moving. On the right is the famous star Polaris. Although only the 45th brightest star in the sky, Polaris is famous for appearing stationary. ... Supernova 1994D, visible as the bright spot on the lower left, occurred in the outskirts of disk galaxy NGC 4526. ... Many bright nebulae and star clusters in planet Earth's sky are associated with the name of astronomer Charles Messier, from his famous 18th century catalog. ... Saturn at Opposition . ...

... 2009 December 11 . Messier Craters in Stereo . Credit Apollo 11 , NASA ; Stereo Image by Patrick Vantuyne . ... His name is also given to these two large and remarkable craters on the Moon. ... Intended to be viewed with red/blue glasses (red for the left eye), this striking stereo picture of the crater pair was recently created from high resolution scans of two images ( AS11-42-6304 , AS11-42-6305 ) taken during the Apollo 11 mission to the moon. ... About APOD | ...

... ESO, the European Southern Observatory . ... Travel and Contacts . Travel to ESO Headquarters . ... ESO . ... Survey Telescopes . ... ESO Supernova . ... Star Clusters . ... Stars@ESO . ... ESO 3.6-metre telescope . ... MPG/ESO 2.2-metre telescope . ... ESO 1-metre Schmidt telescope . ... Future Projects . ... This NASA/ESA Hubble Space Telescope image shows the positions of the past, present and predicted future appearances of the Refsdal supernova behind the galaxy cluster€а MACS J1149+2223 . ...

... Tonight's Sky . ... The Magazine . ... Observing . ... Magazine . ... Star Atlas . ... stars . ... 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 . ... Astronomy for Kids . ... stars and star clusters . ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email...

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. ...

... 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. ...

Stellar Clusters are very useful laboratories for empirically studying stellar evolution. ... All cluster stars are at the same distance . All cluster stars have the same physical age . ... CM diagram Young Cluster In this case we see the Main Sequence fully represented. The blue dots represent massive stars with short main sequence lifetimes. ... Thus, identifying the most massive star which is still on the main sequence is an effective means of determining the age of a stellar cluster. ...

... HST Phase II Proposal Instructions for Cycle 20 > Chapter 3: Fixed and Generic Targets > 3.3 Target Category and Target Description [Description] . ... Each target must be assigned a single primary category from Table 3.2 , and at least one descriptive keyword , chosen from the appropriate Table 3.3 through Table 3.9 (see Table 3.2 for which table is appropriate for each category). ... Table 3.3: Descriptive Keywords for STAR and EXT-STAR . ... Table 3.6: Descriptive Keywords for CLUSTER OF GALAXIES...

... May 22, 1996 . Star Cluster in the Rosette Nebula . ... Explanation: Embedded in the center of the colorful and photogenic Rosette Nebula is a bright, young open cluster . The bright blue stars in this cluster, labelled NGC 2244, emit ultraviolet light that knocks electrons away from hydrogen atoms . ... The Rosette Nebula is thousands of light years distant, but light would take only about 100 years to cross it. ... Tomorrow's picture: The Violent Star Cluster 30 Doradus . ... About APOD | ...

... 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. ...

... 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 "), . ...

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! ...

... We address a question if globular clusters (GC) in a protogalaxy could for some time evolve chemically as isolated systems, enriching themselves with heavy elements produced in first supernova events that follow initial star formation. We determine both the critical mass of a protoglobular cluster that is needed to retain the ejecta of the very first supernova, and the critical energy (i.e., number of supernovae) that is needed to expel the residual gas from a cluster of a given mass. ...

. Please standby and you will be automatically connected to the new location of the unframed Supernova page. Or, click on the link above. If you have questions or problems, please email me at David Bishop dbishop@vhdl.org . Last modified: Mon Aug 27 12:40:15 EDT 2001

... ATNF Home . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . ... Mopra radio telescope . ... Visiting Parkes radio telescope . ... Parkes radio telescope webcam . ... Although galaxy mergers are thought to play an important role in forming elliptical galaxies, mergers in galaxy clusters have drawn less attention compared to mergers in field environments due to high peculiar velocities of cluster galaxies. ...

... 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 ...

... 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. ...

Many intermediate-age star clusters in the Magellanic Clouds exhibit very unusual features in their colour-magnitude diagrams that suggest they may have formed their stars over periods spanning hundreds of millions of years per cluster. ... Nonetheless, this interpretation is enticing in the context of the formation of ancient globular clusters, which almost always exhibit puzzling abundance patterns that apparently require multiple episodes of star formation to explain. ...

... Structure of Data . ... Catalog . ... In SAI OCL Catalog, we introduce our work on investigation of the Milky Way system of open star clusters. The main goal of our study is a search for new clusters using huge surveys. 168 new clusters have been already discovered by us using J,H,Ks data from 2MASS point source catalog. ... For 141 new clusters, we found their physical parameters using J,H,Ks data from 2MASS catalog and, for a number of clusters, our UBVRI CCD observational magnitudes. ...

... Current Work ­ Attempting to understand AGN feedback in galaxy clusters AMI ­ Where does AMI fit in? ... Feedback needed to offset cooling and explain the deficit of cold, molecular gas in cluster cores. ... Some already observed with AMI ­ Ideally want to observe many more (~100 ­ 150) cooling clusters in this energetically important but often overlooked frequency range. ... If bright at 1.4GHz then observe with AMI Campaign to observe many clusters at higher frequency with GISMO (2mm). ...