... 2003 December 15 . Open Star Clusters M35 and NGC 2158 . ... NGC 2158 is four times more distant that M35 , over 10 times older, and much more compact as it contains many more stars in roughly the same volume of space. NGC 2158 's bright blue stars have self-destructed , leaving cluster light to be dominated by older and yellower star s. Both clusters are visible toward the constellation of Gemini -- M35 with binoculars and NGC 2158 with a small telescope. ... About APOD | ...

... Credit Copyright: Canada-France-Hawaii Telescope , J.-C. Cuillandre ( CFHT ), Coelum Explanation: Open clusters of stars can be near or far, young or old, and diffuse or compact. ... Bright blue stars frequently distinguish younger open clusters. ... NGC 2158 's bright blue stars have self-destructed , leaving cluster light to be dominated by older and yellower star s. Both clusters are visible toward the constellation of Gemini -- M35 with binoculars and NGC 2158 with a small telescope. ...

... 2000, ApJ, 537, L49 . ... F. Palla . Invited Talk at the IAU Symposium 200 "The formation of binary stars" eds. R.D. Mathieu and H. Zinnecker (ASP Conf. Ser.) in press . Optical follow-up of ROSAT discovered candidate members of the open cluster Coma Berenices . ... 2000, A , in press . ... 2000, ApJ, in press . ... 2000, ApJ, in press (Sept. ... 2000, ApJ Lett., in press . ... Click to examine publications from other years . ... Star Formation Group . ... Arcetri Home Page . ...

.

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. ...

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! ...

This site provides on-line access to publications, figures, and data tables related to an extensive multi-wavelength observational program to study distant galaxy clusters. ... Lori Lubin, Bev Oke, and Marc Postman have been studying a sample of 9 distant clusters (some taken from the PDCS) using the Keck 10m telescope, the HST, and the KPNO 4m (for IR imaging). ... A Study of Nine High-Redshift Clusters of Galaxies: I. The Survey, . ... A Study of Nine High-Redshift Clusters of Galaxies: II. ...

... 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 ...

... The Pleiades star cluster, also known as the Seven Sisters and Messier 45, is a conspicuous object in the night sky with a prominent place in ancient mythology . ... The stars in the Pleiades are thought to have formed together around 100 million years ago, making them 1/50th the age of our sun, and they lie some 130 parsecs (425 light years ) away. ... Data for these stars are listed in a table below. ... Yes . ... WEBDA Pleiades cluster data . ... M45: The Pleiades Star Cluster (2007 November 18) ...

... D. J. Burke and J. Patrick Henry . The Astrophysical Journal, submitted. ... S. Brough, W. J. Couch, C. A. Collins, T. Jarrett, D. J. Burke , R. G. Mann . ... D. A. Wake, C. A. Collins, R. C. Nichol, L. R. Jones, D. J. Burke . ... R. Sadat, A. Blanchard, S. C. Vauclair, D. H. Lumb, J. Bartlett, A. K. Romer, J.-P. Bernard, M. Boer, P. Marty, J. Nevalainen, D. J. Burke , C. A. Collins, R. C. Nichol, . ... S. Majerowicz, D. M. Neumann, A. K. Romer, R. C. Nichol, D. J. Burke , C. A. Collins . ...

... BLUE STRAGGLER STARS are unusually hot and bright stars found in the cores of ancient star clusters known as globulars. ... BACKGROUND (from wikipedia): Blue straggler stars are stars in open or globular clusters that are hotter and bluer than other cluster stars having the same luminosity. ... There is evidence in favor of this view, notably that blue straggler stars appear to be much more common in dense regions of clusters, especially in the cores of globular clusters. ...

. Similar to an optical lens bending light to form an image, the galaxy cluster Abell 2218 is so massive and compact that light rays passing through it are deflected by its enormous gravitational field. This process (called gravitational lensing) magnifies, brightens, and distorts images of objects that lie far beyond the cluster. The thin arcs are distorted images of distant galaxies roughly 5-10 times farther than the cluster. A. Fruchter / STScI / NASA

... 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. ...

... 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. ...

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. ...

Searching for Ultra Compact Binaries in Globular Clusters What Are Ultra Compact Binaries? ... An ultra compact binary is a binary that consists two white dwarf To source the FITS files that contained the UV images, the sky coordinates stars and has an orbital period shorter than ~70min (A binary and the details on brightness for each star in each globular cluster we were consists of two stars orbiting around their centre of mass, it enables investigating, we used the XMM online archive. ...

Our early publications since 1990 till 1995 year . ... 7.Yu.I.Izotov, N.G.Guseva, V.A.Lipovetsky, A.Yu.Kniazev, J.A. Stepanian, 1990, Nature, 343, 238, Unusual low heavy-element abundance found in the blue compact galaxy SBS 0335-052 8.Yu.I.Izotov, N.G.Guseva, V.A.Lipovetsky, A.Yu,Kniazev, J.A.Stepanian, 1990, Physical Processes in Fragmentation and Star Formation, 1990, Kluwer Academic Publisher, p.235-240. ... New blue compact dwarf galaxies with low heavy-element abundances. ... 1993. ...

Galactic Wind Shells and High Redshift Radio Galaxies . ... M.Krause . Astronomy & Astrophysics, v.436, 845-851 . Very Light Jets II: Bipolar large scale simulations in King atmospheres [small version] . ... Simulations of Astrophysical Jets in Dense Environments . M.Krause, V.Gaibler & M.Camenzind . in: High Performance Computing in Science and Engeneering '05 eds.: E.Krause, W.J ger & M.Resch. ... M.Krause & M.Camenzind . ... Martin Krause & Paul Alexander . ... Martin Krause . ...

... Contacts . 2012: . ... We refined the fundamental parameters of the components, the orbital periods, and the conditions of photospheric heating of the secondary component by the ultraviolet radiation of the hot component. ... The observations of the star clusters associated with ultra-luminous x-ray sources (ULXs) in four galaxies on the 6-meter and VLT telescopes have shown that all the ULXs are located within 200pc of very young star clusters (younger than 5 million years). ... Archive . ...

... Bad Astronomy . ... Bitesize Astronomy . ... The next step up are true clusters, called open clusters . Open clusters (sometimes misleadingly called "galactic clusters") are groups of stars ranging in size from a few dozen stars up to tens of thousands. ... The youngest is about 1 or 2 million years old, while the oldest is about 6 or 7 billion years, making it just older than our own solar system. ... So by looking at the stars in the cluster we can tell pretty well how old they are. ...