... Archives . ... Grating Dispersion [Equation of the Week] . Jun 8th, 2008| 09:45 pm | ... Despite no statistic related discussion, a paper comparing XSPEC and ISIS, spectral analysis open source applications might bring high energy astrophysicists? interests this week. [astro-ph:0806.0650] Kimball and Ivezi\?c . ... A Statistical Analysis of the ?Internal Linear Combination? ... Category: arXiv , Data Processing , gamma-ray , High-Energy , Methods , Stat | ... Chandra Blog . ...

... In our numerical experiments we mainly considered two sets of simulated data provided by R. Hanisch, namely the Star Cluster and the Elliptical Galaxy 2 (Hanisch 1993). Fig. 1 shows the relative error (the inverse of the signal-to-noise ratio) achieved using the Tikhonov method in the restoration of the above mentioned images. ... As a result, Tikhonov regularization takes about sec on the initial mesh and sec on an extended mesh (IBM RISC 6000/560 with ESSL 2). ...

... NGC 6903: The Butterfly Nebula . ... Star Size Comparisons . ... The Nebula's glowing gas surrounds hot young stars at the edge of an immense interstellar molecular cloud. Curiosity: Wheels on Mars . ... The Milky Trail . ... The Eagle Nebula and the Swan Nebula span this broad starscape, a telescopic view of the Sagittarius spiral arm toward the center of our Milky Way galaxy. ... While most spiral galaxies, including our own Milky Way, have two or more spiral arms, NGC 4725 has only one. ...

Title: A New Model of the Gravitational Lens 0957+561 and a Limit on the Hubble Constant . Authors: Norman A. Grogin , Ramesh Narayan (Harvard Univ.) ... Title: ROSAT/PSPC observation of the distant cluster CL0939+472 . ... Title: Interaction in the Bimodal Galaxy Cluster A3528 . ... Title: Cosmological Implications of Galaxy Cluster Evolution . ... Title: Galaxy Cluster Virial Masses and Omega . ... Matches 201 to 222 from a total of 222 matches for the search pattern galaxy cluster . ...

... Gravitational wave search provides insights into galaxy evolution and mergers . ... galaxies . ... 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 . ... What are typical star-to-star distances in globular clusters compared to stellar distances in our region of the galaxy? ... RELATED TOPICS: GLOBULAR CLUSTERS . ... Get instant access to subscriber content on Astronomy.com! ...

ESO PR Photo 18b/00 . ... Caption : Images of two of the novae in NGC 1316 that were discovered during the observational programme described in this Press Release. ... In particular, no less than four novae were detected in a single giant galaxy within only 11 days . ... Moreover, the discovery of four novae in one galaxy in the Fornax cluster was possible with only 3 hours of observing time per filter. ... ESO Press Information is available on the WWW at . http://www.eso.org/outreach/press-rel/ . ...

... This SAS routine allows to compare real columns from two files, with absolute and relative tolerance. ... compare_realcols table =newfile(: table ) reftable=reffile(: table ) colnames= column list (abstol=tol1 reltol=tol2 operation=op) # newfile(: table ): name of the first file with table ( first by default ) # reffile(: table ): name of the second file with table ( first by default ) # column list : names of the columns to be compared (separated by a blank) # tol1 : absolute ...

... Editor's choices for the most educational Astronomy Pictures of the Day about clusters of galaxies: . APOD: 2006 March 21 - The Coma Cluster of Galaxies . ... APOD: 2005 November 22 - A Galactic Collision in Cluster Abell 1185 . ... A prominent example occurs on the left of the above image of the rich cluster of galaxies Abell 1185. ... Recent observations of Abell 1185 have found unusual globular clusters of stars that appear to belong only to the galaxy cluster and not to any individual galaxy. ...

... Comments, Opinions Publications Dnepr Program . Dnepr launch record 17 August 2011. Cluster Launch of Dnepr LV 22 August 2013 KOMPSAT-5 Launch 21 November 2013. Dnepr Cluster Mission 2013 19 June 2014. ... ISC Kosmotras announces signing of a launch contract with T B?TAK Space Technologies Research Institute (T B?TAK UZAY) for injection of RASAT spacecraft - the first Earth observation satellite designed and manufactured in Turkey by Dnepr LV in 2010. ... Dnepr LV Performance . ...

... 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. ...

... We have made observations of the Perseus cluster with the Westerbork Telescope at 610 MHz. ... Several newly detected sources are identified with cluster galaxies. ... No evidence is found for the existence of the previously reported ~ 65'x25' cluster halo, 3C 84B. Key words: radio galaxies - clusters - tailed radio sources buoyancy The Perseus Cluster of galaxies is one of the most fascinating systems accessible to extragalactic astronomers. ...

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. ...

... Stellar cinders . Born-again stars . ... Heavyweight Stars . ... What will happen inside the Sun and why? ... These are questions about "stellar evolution", the history of stars as they are transformed by nuclear processes deep inside. ... Most of what we know about stellar evolution comes from computer models of stars. ... We learn about the evolution of high-mass stars from HR diagrams of young galactic open clusters, and the evolution of low-mass metal-poor stars from old globular clusters. ...

. Comment on J1842+7946 . Comparing the brightnesses of the two main features seen in our 5 GHz image with higher frequency VLBI images available in the literature (at 8.4 GHz from the USNO database and at 15 GHz by Kellermann et al. (1998)), one can conclude that the NW component has a steeper spectrum since the SE one becomes relatively stronger as the observing frequency increases. VLBApls home page . Last modified: 16 Oct 2000

... ESO, the European Southern Observatory . ... ESO Acronyms . ... Survey Telescopes . ... ESO 3.6-metre telescope . ... MPG/ESO 2.2-metre telescope . ... ESO 1-metre Schmidt telescope . ... First Objects . ... The relative sizes of a number of objects, including the three (known) members of Alpha Centauri triple system and some other stars for which the angular sizes have also been measured with the Very Large Telescope Interferometer (VLTI) at the ESO Paranal Observatory (Chile) during the year 2002....

... We publish 16 Doppler imaging temperature maps for the years 1994-2002 of the active RS CVn star II Peg. ... Through Doppler imaging we want to study the spot evolution of the star and in particular compare this with previous results showing a cyclic spot behaviour and persistent active longitudes. ... The derived temperature maps are quite similar to the ones obtained earlier with a different methods, the main differences occurring in the spot latitudes and relative strength of the spot structures....

Find Similar Abstracts . ... The velocity of clusters of galaxies relative to the microwave background. ... BACKGROUND RADIATION, GALACTIC CLUSTERS, MICROWAVE SCATTERING, VELOCITY MEASUREMENT, HIGH TEMPERATURE GASES, MICROWAVES, POLARIZED RADIATION, RADIAL VELOCITY, RADIO ASTRONOMY, THOMSON SCATTERING . ... Use: Authors Title Abstract Text Text Query with Keywords Return: Query Results Query Form Database: Astronomy Instrumentation Physics and Geophysics ABSTRACT QUERY USER FEEDBACK HELP ...

Astronotes Armagh Planetarium's Stellar Blog! ... Armagh Planetarium . ... Stars . ... Space Flight . ... Monthly Sky Notes . ... By admin October 1, 2010 Posted in: Stars . A sky of blazing stars (Image Credit: NASA/ESA) . Imagine that once the Sun sets, rather than a dark sky sprinkled with a few thousand dim stars, we had a sky blazing with ten thousand or so stars blazing brighter than Venus. ... Planets orbiting stars in the NGC 3603 Young Cluster would experience just such a sky. ...

RELATIVE SUNSPOT NUMBERS Description of Data from SGD Explanation of Data Reports: Relative Sunspot Numbers -- The relative sunspot number is an index of the activity of the entire visible disk of the Sun. ... The provisional daily Zurich relative sunspot numbers, Rz, were based upon observations made at Zurich and its two branch stations in Arosa and Locarno and communicated by M. Waldmeier of the Swiss Federal Observatory. ... This indicates the uncertainty above and below the predicted number. ...

Contents. planet: 5 - Jupiter satellites: J1 - Io : 81, J2 - Europa : 24, J3 - Ganymede :129, J4 - Callisto : 36 total number: 270 type: relative dates: 1996-1997 observatory: see observatories list in the comments Reference. Emelianov N. V., Vashkovjak S. N. (2009) Astrometric results of the observations of the mutual occultations and eclipses of the Galilean satellites of Jupiter in 1997. ... X coordinate in arcseconds (topocentric for mutual occultation or heliocentric for mutual eclipse) 10. ...