... 2006 September 10 . Star Clusters Young and Old . ... Galactic or open star clusters are relatively young swarms of bright stars born together near the plane of our Milky Way Galaxy. Separated by about a degree on the sky, two nice examples are M46 (upper left) 5,400 light-years in the distance and M47 (lower right) only 1,600 light-years away toward the nautical constellation Puppis . Around 300 million years young M46 contains a few hundred stars in a region about 30 light-years across. ...

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. ...

... Spiral galaxies viewed face-on display a grand design, with graceful spiral arms traced by bright star clusters and glowing stellar nurseries. ... Space Station Shows Off New Robot Arm . ... GRO J1655 40: Evidence for a Spinning Black Hole . ... In the center of a swirling whirlpool of hot gas is likely a beast that has never been seen directly: a black hole. ... The Orion Nebula is a nuturing stellar nursery filled with hot young stars and their natal clouds of gas and dust. ...

... 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. ...

... We have simulated the observations of a very distant cluster of galaxies at high redshift. ... The simulations are made for the HST instruments FOC, WFPC II, and the Advanced Camera, and for an 8-m telescope on the ground equipped with adaptive optics. ... A comparison of the fields of view of post-COSTAR HST imaging instruments with the Advanced Camera (AC) and the ground-based adaptive optics camera (AO) is shown in Fig. 1 superimposed on the noise-free cluster simulation. ...

... Science . ... Science Users Information > Science Publications > Archive of the ESO Enews > ESO-Enews #14: September 2009 . ... Observing Facilities . ... Science Archive Facility . ... To obtain earlier raw data that is still covered by the proprietary period PIs may use the normal ESO Archive interface .. ... For more information about the above item, or to subscribe to the archive RSS feed to stay informed on the latest archive developments, please visit the Science Archive Facility . ...

IFP gallery SCORPIO (since 2000). Here some data observed on the 6m telescope with IFP installed in the SCORPIO focal reducer are presented. ... Velocity field . Mkn 1157 was observed 1 Sep. 2002 in the Ha emission line. Texp =32x240 sec, seeing 1.5", IFP260. ... This galaxy was observed September, 23 2000 in the Ha emission line, Texp=32x120 sec, seeing 2.5", IFP260. ... PV Cep was observed at the 6m telescope in May, 25 2003 in the [SII] 6716A with IFP501, Texp=36x200 sec, seeing 1.0". ...

... 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) ...

... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. September 22, 1998 . M61: Virgo Spiral Galaxy . ... Explanation: M61 is a barred spiral galaxy located in the nearby Virgo Cluster of Galaxies . Visible in M61 are a host of features common to spiral galaxies : bright spiral arms , a central bar , dust lanes , and bright knots of stars. ... About APOD > . ...

... Over the first 4 years, its X-ray telescopes eROSITA and ART-XC will survey the whole sky with a record sensitivity in the 0.5-10 keV energy band. ... The goal of the second international Spectrum-RG conference is to discuss the different scientific topics addressed by the mission, synergies with surveys at other wavelengths, and requirements to follow-up observations.Contributed talks and poster presentations are invited on the topics related to the SRG science goals. ... Active galactic nuclei . ...

... 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. ...

The ETG Mass - Size relation in different environment from z~1.6 to present Simona Mei - GEPI - Observatory of Paris - University of Paris D. Diderot Marc Huertas-Company , Francesco Shankar , Lauriane Delaye, Rossella Licitra, Anand Raichoor, Mariangela Bernardi, Chris Lidman + ACS GTO, COSMOS collaborators Wednesday , September 4, 13 Anand Raichoor Marc Huertas-Company Lauriane Delaye Rossella Licitra Francesco Shankar Wednesday , ... 2013 HAWKI Cluster survey (Lidman et al. ...

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! ...

... Archives . ... my first AAS. ... I was questioned by two attendees, acquainted before the AAS, if I can suggest them clustering methods relevant to their projects. ... classification vs. clustering or supervised learning vs. unsupervised learning : the former terms from the pairs indicate the fact that the scientist already knows types of objects in his hands. ... Tags: Classification , clustering , cosmology , spatial statistics , supervised learning , test , unsupervised learning . ...

In this diagram, one of the clusters is shown to the right as a collection of galaxies, which are seen as dots. The hot gas filling the cluster and filament is illustrated with purple. The unusual galaxy and the angle of its bent lobes are illustrated in the callout. Infrared-bright galaxies measured by Spitzer are represented in the diagram with blue colors, and the brightest "starburst" galaxies are the largest dots. ...

ARCSAT ID NUMBER: AS06 DESCRIPTIVE TITLE: Monitoring H-alpha Variability in Be Stars in Young Clusters PI: Steven Souza ( Williams College ) OBSERVER(S): Steven Souza UNCERTIFIED/UNTRAINED OBSERVERS: none presently planned COLLABORATORS: none CONTACT INFORMATION: Steven Souza ; ssouza@ ... As an early ARCSAT user I found that data obtained using SurveyCam and narrowband filters on loan to ARC from Williams College are compatible with those obtained at Williams. ...

... Cancellation occurs. ... The cancellation in this small region exists until 08:00 when all the negative fragments disappeared, but rarely see any X-ray response. 02:30 Many small positive fragments emerge at south. Then they become stronger and move toward the preexisting positive ones to form a bigger one. A cluster of negative fragments with some weak positive ones nearby present at the south. ... Some other negative fragments moving from north of the positive one start to take action. ...

... LMC Project Outline . NGC 1818 Initial Results . ... The Large Magellanic Cloud (LMC) is uniquely suitable for the study of massive star clusters at all stages of evolution. By combining HST observations of these clusters with N-body models we hope to understand the origin and evolution of rich star clusters in our own Galaxy, in the LMC, and beyond. ... We aim to combine our HST observations with N-body models to understand the formation and evolution of globular clusters. ...

... 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. ...

... 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. ...