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. ...

... The routines implemented are CLUSTER which has 8 options for hierarchical clustering and PARTITION which carries out non--hierarchical clustering. ... The former is non--hierarchical clustering or partitioning. The latter is hierarchical clustering. Brief consideration will show that a sequence of n-1 agglomerations are needed to successively merge the two closest objects and/or clusters at each stage, so that we have a set of n (singleton) clusters, n-1 clusters, ..., 2 clusters, 1 cluster. ...

... Posts tagged ?clusters? Apr 27th, 2008| 11:29 am | ... The last paper in the list discusses MCMC for time series analysis, applied to sunspot data. ... ArXiv] 4th week, Apr. ... ArXiv] 3rd week, Apr. ... Entries RSS . ... Algorithms arXiv Astro Bad AstroStat Bayesian CHASC Cross-Cultural Data Processing Fitting Frequentist Galaxies gamma-ray High-Energy Imaging Jargon Job Languages MC MCMC Meta Methods Misc News Nuggets Objects Optical Physics Quotes Spectral Stars Stat Timing Uncertainty X-ray . ...

... In 1930, Trumpler noticed that linear diameters (LD) of open clusters increase with distance (D) from the Sun. ... Since that time, the interstellar absorption has become one of the best studied factor in astrophysics, and we may hope that current OCL distance scales are free from this LD-D correlation. To verify if this is the case we have chosen several modern OCL distance scales and test them with the same clusters and the same angular diameters that Trumpler had used back in 1930. ...

... A homogeneous chemical analysis of the inner Galactic disk from the first data release of Gaia-ESO . ... Gaia-ESO is a public spectroscopic survey designed with this goal in mind. ... These first results highlight the potential of the Gaia-ESO survey to explore areas of the Milky Way still poorly studied, such as the inner disk, and to give new constraints on Galactic chemical evolution models. ... Map of observed targets of the first data release of the Gaia-ESO Survey. ...

... We want to know time-scales, and sequences of events, and the ages of stars. ... We would, ideally, like to create a solar comparison sample by finding stars of essentially the same mass, composition, and age and then observing the range of behavior they exhibit. ... At best we can estimate a star 's age. ... Having to construct models that work consistently across a broad range of masses constrains the problem, and yet even for the nearest open clusters we do not know the age to even 10%. ...

... ATNF Home . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . ... Mopra radio telescope . ... Australia Telescope 20GHz Survey . ... Visiting Parkes radio telescope . ... Parkes radio telescope webcam . ... The results of 21 cm H I survey observations are presented for two fields, centered on the Centaurus and Fornax southern galaxy clusters. ... Implications for the Parkes Multibeam All Sky Survey . ...

... 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. ...

... Next: Unsupervised Catalog Classification Up: Object Detection and Previous: Classification of Objects . ... Multi-resolution allows for image analysis in terms of different scales. ... This approach is used for the detection (and subsequent analysis) of globular cluster systems around elliptical galaxies, and for image characterization and object trawling in large image databases. ... The applicability of this approach to object detection in large image collections has been investigated. ...

J/AstL/vol/page SAI Open Clusters Catalog (Glushkova+, 2009) ================================================================================ Automated search for star clusters in large multiband surveys. ... Color excesses E(B-V), distance moduli and ages were determined for 141 new and 27 known, but poorly studied clusters. We present the Sternberg Astronomical Institute Open Clusters Catalog (SAI OCL Catalog) of coordinates, diameters and main physical parameters of these clusters. ...

... Astrophysics Group . Research . Cosmic Microwave Background (CMB) . ... A significant fraction of the Astrophysics Group is involved in work on the Cosmic Microwave Background, both experimental and theoretical. We are currently operating the Arcminute Microkelvin Imager , an arcminute-scale survey telescope, and developing analysis techniques for the Planck satellite. ... 2013, Astrophysics Group, Cavendish Laboratory, JJ Thomson Avenue, Cambridge, CB3 0HE . ...

... Explanation: Huge clusters of galaxies are surely colliding in Abell 520 but astrophysicists aren't sure why the dark matter is becoming separated from the normal matter. The dark matter in the above multi-wavelength image is shown in false blue, determined by carefully detailing how the cluster distorts light emitted by more distant galaxies. ... Publications with keywords: cluster of galaxies - dark matter . Publications with words: cluster of galaxies - dark matter . ...

... Kopylov, A.I., Kopylova, F.G. "Structure of galaxy groups and clusters and measurement of their masses", . ... Kopylova, F.G., Kopylov, A.I. "Peculiar motions of galaxy clusters and groups in the Hercules and Leo supercluster regions", . ... Kopylova, F.G., Kopylov, A.I. "Analysis of the properties of clusters of galaxies in the region of the Leo supercluster", . ... Kopylova, F.G., Kopylov, A.I. "Analysis of the properties of clusters of galaxies in the region of the Ursa Major supercluster", . ...

... 1st Announcement IAU Symposium 312 Star Clusters and Black Holes Across Cosmic Time, Beijing, China, Aug. 25-29, 2014 . ... SUBJECT: 1st Announcement IAU Symposium 312 Star Clusters and Black Holes Across Cosmic Time, Beijing, China, Aug. 25-29, 2014 . ... which will be held in Beijing, P.R. China, from August 25-29, 2014, hosted by Chinese Academy of Sciences . ... China), . ... 1st Announcement IAU Symposium 312 Star Clusters and Black Holes Across Cosmic Time, Beijing, China, Aug. ...

... 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. ...

... Science . ... Science Users Information > Science Activities > PhD Thesis Topics offered by ESO Faculty Members > Studying the Cosmological Evolution of Galaxy Clusters with (Sub-)mm Observations . ... Data Handling and Products . ... ESO Data . ... Studies of the Planck data set with optical and sub-mm follow-up observations give new insights about the early assembly of the first clusters, and the later evolution of their gas content as well as of their population of star-forming galaxies. ...

Find Similar Abstracts . ... Intergalactic gas in clusters of galaxies, the microwave background, and cosmology . ... In addition, it may be feasible to determine the peculiar velocity of clusters relative to the microwave background. ... 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 ...

ATMoB "Open Cluster Observing Award " Guidelines Purpose: To promote observing among the membership of the Amateur Telescope Makers of Boston through participation in the Open Clusters Observing Awards program. Introduction: This awards program is oriented towards visually observing open clusters above magnitude 9.9. ... It turns out that a very unprejudiced and convenient method to dermine the limiting magnitude is to count the number of visible stars in certain areas on the sky. ...

Next: J.E. Chambers, Research Astronomer Up: Research Previous: Research Contents . ... Solar Variability and Climate . Other Activities . ... Applied to data of flares on Gliese866 he was able to estimate the area of hydrogen emitting flare regions as 1-13% of the stellar surface. ... As partners in the project, Armagh Observatory has been asked to contribute to the selection process in exchange for priority access to the data which will eventually flow from the satellite. ...

A Canadian and American team of Astronomers have used the 305-m wide Arecibo radio dish, the world's largest and most sensitive radio telescope, to uncover a dozen new super-fast-spinning pulsars. The team directed their search for these rare and exotic stars by pointing the Arecibo radio telescope towards massive star clusters, called Globular Clusters, orbiting our Milky Way galaxy. ... One of the most exotic residents in the Globular cluster system are the millisecond pulsars. ...