VLT Spectroscopy of Globular Cluster Systems?
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Lateinischer Name: Deutscher Name: Hya Hydra Wasserschlange
Lateinischer Name: Deutscher Name: Hya Hydra Wasserschlange Atlas Karte (2000.0) Kulmination um Cambridge 10, 16, Mitternacht: Star Atlas 17 12, 13, Sky Atlas Benachbarte Sternbilder: 20, 21 Ant Cnc Cen Crv Crt Leo Lib 9. Februar Lup Mon Pup Pyx Sex Vir Deklinationsbereic h: -35° ... 7° Fläche am Himmel: 1303° 2 Mythologie und Geschichte: Bei der nördlichen Wasserschlange überlagern sich zwei verschiedene Bilder aus der griechischen Mythologie. Das erste Bild zeugt von der eher harmlosen Wasserschlange aus der Geschichte des Raben : Der Rabe wurde von Apollon ausgesandt, um mit einem goldenen Becher frisches Quellwasser zu holen. Stattdessen tat sich dieser an Feigen gütlich und trug bei seiner Rückkehr die Wasserschlange in seinen Fängen, als angebliche Begründung für seine Verspätung. Um jedermann an diese Untat zu erinnern, wurden der Rabe samt Becher und Wasserschlange am Himmel zur Schau gestellt. Von einem ganz anderen Schlag war die Wasserschlange, mit der Herakles zu tun hatte: In einem Sumpf in der Nähe von Lerna, einem See und einer Stadt an der Küste von Argo, hauste ein unsagbar gefährliches und grässliches Untier. Diese Schlange soll mehrere Köpfe gehabt haben. Fünf sollen es gewesen sein, aber manche sprechen auch von sechs, neun, ja fünfzig oder hundert Köpfen, aber in jedem Falle war der Kopf in der Mitte unverwundbar. Fürchterlich war es, da diesen grässlichen Mäulern - ob die Schlange nun schlief oder wachte - ein fauliger Atem, ein Hauch entwich, dessen Gift tödlich war. Kaum schlug ein todesmutiger Mann dem Untier einen Kopf ab, wuchsen auf der Stelle zwei neue Häupter hervor, die noch furchterregender waren. Eurystheus, der König von Argos, beauftragte Herakles in seiner zweiten Aufgabe diese lernäische Wasserschlange zu töten. -
Extending the M (Bh)-Sigma Diagram with Dense Nuclear Star Clusters
Mon. Not. R. Astron. Soc. 000, 000–000 (0000) Printed 11 November 2018 (MN LATEX style file v2.2) Extending the Mbh–σ diagram with dense nuclear star clusters Alister W. Graham1⋆, 1 Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia. Submitted 08 Aug, 2011 ABSTRACT Four new nuclear star cluster masses, Mnc, plus seven upper limits, are provided for galaxies with previously determined black hole masses, Mbh. Together with a sample of 64 galaxies with direct Mbh measurements, 13 of which additionally now have Mnc measurements rather than only upper limits, plus an additional 29 dwarf galaxies with available Mnc measurements and velocity dispersions σ, an (Mbh + Mnc)–σ diagram is constructed. Given that major dry galaxy merger events preserve the Mbh/L ratio, and given that L ∝ σ5 for luminous galaxies, it is first noted that the observation 5 Mbh ∝ σ is consistent with expectations. For the fainter elliptical galaxies it is known 2 that L ∝ σ , and assuming a constant Mnc/L ratio (Ferrarese et al.), the expectation 2 that Mnc ∝ σ is in broad agreement with our new observational result that Mnc ∝ σ1.57±0.24. This exponent is however in contrast to the value of ∼4 which has been reported previously and interpreted in terms of a regulating feedback mechanism from stellar winds. Finally, it is predicted that host galaxies fainter than MB ∼−20.5 mag (i.e. those 5 not formed in dry merger events) which follow the relation Mbh ∝ σ , and are thus not ‘pseudobulges’, should not have a constant Mbh/Mhost ratio but instead have ∝ 5/2 Mbh Lhost. -
SUPERMASSIVE BLACK HOLES and THEIR HOST SPHEROIDS III. the MBH − Nsph CORRELATION
The Astrophysical Journal, 821:88 (8pp), 2016 April 20 doi:10.3847/0004-637X/821/2/88 © 2016. The American Astronomical Society. All rights reserved. SUPERMASSIVE BLACK HOLES AND THEIR HOST SPHEROIDS. III. THE MBH–nsph CORRELATION Giulia A. D. Savorgnan Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia; [email protected] Received 2015 December 6; accepted 2016 March 6; published 2016 April 13 ABSTRACT The Sérsic R1 n model is the best approximation known to date for describing the light distribution of stellar spheroidal and disk components, with the Sérsic index n providing a direct measure of the central radial concentration of stars. The Sérsic index of a galaxy’s spheroidal component, nsph, has been shown to tightly correlate with the mass of the central supermassive black hole, MBH.TheMnBH– sph correlation is also expected from other two well known scaling relations involving the spheroid luminosity, Lsph:theLsph–n sph and the MLBH– sph. Obtaining an accurate estimate of the spheroid Sérsic index requires a careful modeling of a galaxy’s light distribution and some studies have failed to recover a statistically significant MnBH– sph correlation. With the aim of re-investigating the MnBH– sph and other black hole mass scaling relations, we performed a detailed (i.e., bulge, disks, bars, spiral arms, rings, halo, nucleus, etc.) decomposition of 66 galaxies, with directly measured black hole masses, that had been imaged at 3.6 μm with Spitzer.Inthispaper,the third of this series, we present an analysis of the Lsph–n sph and MnBH– sph diagrams. -
Does the Fornax Dwarf Spheroidal Have a Central Cusp Or Core?
Research Collection Journal Article Does the Fornax dwarf spheroidal have a central cusp or core? Author(s): Goerdt, Tobias; Moore, Ben; Read, J.I.; Stadel, Joachim; Zemp, Marcel Publication Date: 2006-05 Permanent Link: https://doi.org/10.3929/ethz-b-000024289 Originally published in: Monthly Notices of the Royal Astronomical Society 368(3), http://doi.org/10.1111/ j.1365-2966.2006.10182.x Rights / License: In Copyright - Non-Commercial Use Permitted This page was generated automatically upon download from the ETH Zurich Research Collection. For more information please consult the Terms of use. ETH Library Mon. Not. R. Astron. Soc. 368, 1073–1077 (2006) doi:10.1111/j.1365-2966.2006.10182.x Does the Fornax dwarf spheroidal have a central cusp or core? , Tobias Goerdt,1 Ben Moore,1 J. I. Read,1 Joachim Stadel1 and Marcel Zemp1 2 1Institute for Theoretical Physics, University of Zurich,¨ Winterthurerstrasse 190, CH-8057 Zurich,¨ Switzerland 2Institute of Astronomy, ETH Zurich,¨ ETH Honggerberg¨ HPF D6, CH-8093 Zurich,¨ Switzerland Accepted 2006 February 8. Received 2006 February 7; in original form 2005 December 21 ABSTRACT The dark matter dominated Fornax dwarf spheroidal has five globular clusters orbiting at ∼1 kpc from its centre. In a cuspy cold dark matter halo the globulars would sink to the centre from their current positions within a few Gyr, presenting a puzzle as to why they survive undigested at the present epoch. We show that a solution to this timing problem is to adopt a cored dark matter halo. We use numerical simulations and analytic calculations to show that, under these conditions, the sinking time becomes many Hubble times; the globulars effectively stall at the dark matter core radius. -
THE MAGELLANIC CLOUDS NEWSLETTER an Electronic Publication Dedicated to the Magellanic Clouds, and Astrophysical Phenomena Therein
THE MAGELLANIC CLOUDS NEWSLETTER An electronic publication dedicated to the Magellanic Clouds, and astrophysical phenomena therein No. 115 — 2 February 2012 http://www.astro.keele.ac.uk/MCnews Editor: Jacco van Loon Figure 1: The Small Magellanic Cloud and Galactic globular cluster 47 Tucanae, two of the most beautiful objects in the Southern sky (from Kalirai et al. 2012; South is up and East is to the right). Image courtesy of and c Stephane Guisard, http://www.astrosurf.com/sguisard 1 Editorial Dear Colleagues, It is my pleasure to present you the 115th issue of the Magellanic Clouds Newsletter. There is a lot of attention to star clusters, pulsating stars, binary stars, and the dynamics of the Magellanic System; don’t miss some of the very interesting proceedings papers. It is not yet too late to register for the workshop on mass return from stars to galaxies, at STScI in March, but abstracts need to be in by 3 February (!): http://www.stsci.edu/institute/conference/mass-loss-return The next meeting which should be of interest to readers of this newsletter, is the Magellanic Clouds meeting in Perth, Australia in September – see the announcement at the end of the newsletter for more details. Thanks to those of you who supplied illustrations for this issue. They remain welcome. Also, don’t hesitate to use the ”announcement” type of submission to post results, ideas, requests for observations, et cetera. This is a forum, for discussion and collaboration. The next issue is planned to be distributed on the 1st of April 2012. -
The HST Key Project on the Extragalactic Distance Scale XIV
c The HST Key Project on the Extragalactic Distance Scale XIV. The Cepheids in NGC 1365' N. A. Silbermann,2 Paul Laura Ferrare~e,~Peter B. Stetson,5Barry F. Madore,' Robert C. Kennicutt, Jr.,3 Wendy L. ,Freedman,7.Jeremy R. i\/lould,' Fabio Bre~olin,~ HollandBrad E;. Gibson,' John A. Graham,"Mingsheng Han," John G. 'Based on observations with the NASA/ESA HubbleSpace Telescope obtained at the Space Telescope Science Institute, which is operated by AURA, Inc. under NASA Contract No. NAS5-265.55. 21nfrared Processing and Analysis Center, Jet Propulsion Laboratory, California Institute of Technology, MS 100-22, Pasadena, CA 91125 3Steward Observatory, University of Arizona, Tucson, A2 85721 4Hubble Fellow, California Institute of Technology, Pasadena, CA 91125 5Dominion Astrophysical Observatory, Victoria, British Columbia V8X 4M6 Canada 'NASA ExtragalacticDatabase, Infrared Processing and A4nalysis Center, California Institute of Technology, MS 100-22, Pasadena, CA 91125 70bservatories of the Carnegie Institution of Washington, Pa,sadena CA 91101 'Mount Stromlo and Siding Spring Observatories, Institute of Advanced Studies, ANU, ACT 2611 Australia 'Johns Hopkins University and Space Telescope Science Institute, Baltimore, MD 21218 "Dept. of Terrestrial Magnetism, Carnegie Institution of \Va.shington, Washington D.C. 20015 "University of Wisconsin, Madison, Wisconsin 53706 -- .j ~ ABSTRACT We report the detection of Clepheicl variable stars in the barred spiral galaxy NGC 1365, located in the Fornax cluster, using the Hubble Space Telescope Wide Field and Planetary Camera 2. Twelve V (F555W) and four I (F814W) epochs of observation were obtained. The two photometry packages, ALLFRAME and DoPHOT, were separately used to obtain profile-fitting photometry of all the stars in the HST field. -
2014 Observers Challenge List
2014 TMSP Observer's Challenge Atlas page #s # Object Object Type Common Name RA, DEC Const Mag Mag.2 Size Sep. U2000 PSA 18h31m25s 1 IC 1287 Bright Nebula Scutum 20'.0 295 67 -10°47'45" 18h31m25s SAO 161569 Double Star 5.77 9.31 12.3” -10°47'45" Near center of IC 1287 18h33m28s NGC 6649 Open Cluster 8.9m Integrated 5' -10°24'10" Can be seen in 3/4d FOV with above. Brightest star is 13.2m. Approx 50 stars visible in Binos 18h28m 2 NGC 6633 Open Cluster Ophiuchus 4.6m integrated 27' 205 65 Visible in Binos and is about the size of a full Moon, brightest star is 7.6m +06°34' 17h46m18s 2x diameter of a full Moon. Try to view this cluster with your naked eye, binos, and a small scope. 3 IC 4665 Open Cluster Ophiuchus 4.2m Integrated 60' 203 65 +05º 43' Also check out “Tweedle-dee and Tweedle-dum to the east (IC 4756 and NGC 6633) A loose open cluster with a faint concentration of stars in a rich field, contains about 15-20 stars. 19h53m27s Brightest star is 9.8m, 5 stars 9-11m, remainder about 12-13m. This is a challenge obJect to 4 Harvard 20 Open Cluster Sagitta 7.7m integrated 6' 162 64 +18°19'12" improve your observation skills. Can you locate the miniature coathanger close by at 19h 37m 27s +19d? Constellation star Corona 5 Corona Borealis 55 Trace the 7 stars making up this constellation, observe and list the colors of each star asterism Borealis 15H 32' 55” Theta Corona Borealis Double Star 4.2m 6.6m .97” 55 Theta requires about 200x +31° 21' 32” The direction our Sun travels in our galaxy. -
Scaling Mass Profiles Around Elliptical Galaxies Observed with Chandra
Scaling Mass Profiles around Elliptical Galaxies Observed with Chandra and XMM-Newton Y. Fukazawa1, J. G. Betoya-Nonesa1, J. Pu1, A. Ohto1, and N. Kawano1 Department of Physical Science, School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526 [email protected] ABSTRACT We investigated the dynamical structure of 53 elliptical galaxies, based on the Chandra archival X-ray data. In X-ray luminous galaxies, a temperature increases with radius and a gas density is systematically higher at the optical outskirts, indicating a presence of a significant amount of the group-scale hot gas. In contrast, X-ray dim galaxies show a flat or declining temperature profile against radius and the gas density is relatively lower at the optical outskirts. Thus it is found that X-ray bright and faint elliptical galaxies are clearly distinguished by the temperature and gas density profile. The mass profile is well scaled by a virial radius r200 rather than an optical-half radius re, and is quite similar at (0.001 − 0.03)r200 between X-ray luminous and dim galaxies, and smoothly connects to those of clusters of galaxies. At the inner region of (0.001 − 0.01)r200 or (0.1 − 1)re, the mass profile well traces a stellar mass with a constant mass-to- light ratio of M/LB =3 − 10(M⊙/L⊙). M/LB ratio of X-ray bright galaxies rises up steeply beyond 0.01r200, and thus requires a presence of massive dark matter halo. From the deprojection analysis combined with the XMM-Newton data, we arXiv:astro-ph/0509521v1 18 Sep 2005 found that X-ray dim galaxies, NGC 3923, NGC 720, and IC 1459, also have a high M/LB ratio of 20–30 at 20 kpc, comparable to that of X-ray luminous galaxies. -
April 14 2018 7:00Pm at the April 2018 Herrett Center for Arts & Science College of Southern Idaho
Snake River Skies The Newsletter of the Magic Valley Astronomical Society www.mvastro.org Membership Meeting President’s Message Tim Frazier Saturday, April 14th 2018 April 2018 7:00pm at the Herrett Center for Arts & Science College of Southern Idaho. It really is beginning to feel like spring. The weather is more moderate and there will be, hopefully, clearer skies. (I write this with some trepidation as I don’t want to jinx Public Star Party Follows at the it in a manner similar to buying new equipment will ensure at least two weeks of Centennial Observatory cloudy weather.) Along with the season comes some great spring viewing. Leo is high overhead in the early evening with its compliment of galaxies as is Coma Club Officers Berenices and Virgo with that dense cluster of extragalactic objects. Tim Frazier, President One of my first forays into the Coma-Virgo cluster was in the early 1960’s with my [email protected] new 4 ¼ inch f/10 reflector and my first star chart, the epoch 1960 version of Norton’s Star Atlas. I figured from the maps I couldn’t miss seeing something since Robert Mayer, Vice President there were so many so closely packed. That became the real problem as they all [email protected] appeared as fuzzy spots and the maps were not detailed enough to distinguish one galaxy from another. I still have that atlas as it was a precious Christmas gift from Gary Leavitt, Secretary my grandparents but now I use better maps, larger scopes and GOTO to make sure [email protected] it is M84 or M86. -
Dark Matter Searches Targeting Dwarf Spheroidal Galaxies with the Fermi Large Area Telescope
Doctoral Thesis in Physics Dark Matter searches targeting Dwarf Spheroidal Galaxies with the Fermi Large Area Telescope Maja Garde Lindholm Oskar Klein Centre for Cosmoparticle Physics and Cosmology, Particle Astrophysics and String Theory Department of Physics Stockholm University SE-106 91 Stockholm Stockholm, Sweden 2015 Cover image: Top left: Optical image of the Carina dwarf galaxy. Credit: ESO/G. Bono & CTIO. Top center: Optical image of the Fornax dwarf galaxy. Credit: ESO/Digitized Sky Survey 2. Top right: Optical image of the Sculptor dwarf galaxy. Credit:ESO/Digitized Sky Survey 2. Bottom images are corresponding count maps from the Fermi Large Area Tele- scope. Figures 1.1a, 1.2, 1.3, and 4.2 used with permission. ISBN 978-91-7649-224-6 (pp. i{xxii, 1{120) pp. i{xxii, 1{120 c Maja Garde Lindholm, 2015 Printed by Publit, Stockholm, Sweden, 2015. Typeset in pdfLATEX Abstract In this thesis I present our recent work on gamma-ray searches for dark matter with the Fermi Large Area Telescope (Fermi-LAT). We have tar- geted dwarf spheroidal galaxies since they are very dark matter dominated systems, and we have developed a novel joint likelihood method to com- bine the observations of a set of targets. In the first iteration of the joint likelihood analysis, 10 dwarf spheroidal galaxies are targeted and 2 years of Fermi-LAT data is analyzed. The re- sulting upper limits on the dark matter annihilation cross-section range 26 3 1 from about 10− cm s− for dark matter masses of 5 GeV to about 5 10 23 cm3 s 1 for dark matter masses of 1 TeV, depending on the × − − annihilation channel. -
The European Space Agency
Teachers Notes Booklet 6: Galaxies and the Expanding Universe Page 1 of 18 The European Space Agency The European Space Agency (ESA) was formed on 31 May 1975. It currently has 17 Member States: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, the Netherlands, Norway, Portugal, Spain, Sweden, Switzerland & United Kingdom. The ESA Science Programme currently contains the following active missions: Venus Express – an exploration of our Cluster – a four spacecraft mission to sister planet. investigate interactions between the Rosetta – first mission to fly alongside Sun and the Earth's magnetosphere and land on a comet XMM-Newton – an X-ray telescope Double Star – joint mission with the helping to solve cosmic mysteries Chinese to study the effect of the Sun Cassini-Huygens – a joint ESA/NASA on the Earth’s environment mission to investigate Saturn and its SMART-1 – Europe’s first mission to moon Titan, with ESA's Huygens probe the Moon, which will test solar-electric SOHO - new views of the Sun's propulsion in flight, a key technology for atmosphere and interior future deep-space missions Hubble Space Telescope – world's Mars Express - Europe's first mission most important and successful orbital to Mars consisting of an orbital platform observatory searching for water and life on the Ulysses – the first spacecraft to planet investigate the polar regions around the INTEGRAL – first space observatory to Sun simultaneously observe celestial objects in gamma rays, X-rays and visible light Details on all these missions and others can be found at - http://sci.esa.int. Prepared by Anne Brumfitt Content Advisor Chris Lawton Science Editor, Content Advisor, Web Integration & Booklet Design Karen O'Flaherty Science Editor & Content Advisor Jo Turner Content Writer © 2005 European Space Agency Teachers Notes Booklet 6: Galaxies and the Expanding Universe Page 2 of 18 Booklet 6 – Galaxies and the Expanding Universe Contents 6.1 Structure of the Milky Way ............................................. -
Disk Heating, Galactoseismology, and the Formation of Stellar Halos
galaxies Article Disk Heating, Galactoseismology, and the Formation of Stellar Halos Kathryn V. Johnston 1,*,†, Adrian M. Price-Whelan 2,†, Maria Bergemann 3, Chervin Laporte 1, Ting S. Li 4, Allyson A. Sheffield 5, Steven R. Majewski 6, Rachael S. Beaton 7, Branimir Sesar 3 and Sanjib Sharma 8 1 Department of Astronomy, Columbia University, 550 W 120th st., New York, NY 10027, USA; cfl[email protected] 2 Department of Astrophysical Sciences, Princeton University, 4 Ivy Lane, Princeton, NJ 08544, USA; [email protected] 3 Max Planck Institute for Astronomy, Heidelberg 69117, Germany; [email protected] (M.B.); [email protected] (B.S.) 4 Fermi National Accelerator Laboratory, P. O. Box 500, Batavia, IL 60510, USA; [email protected] 5 Department of Natural Sciences, LaGuardia Community College, City University of New York, 31-10 Thomson Ave., Long Island City, NY 11101, USA; asheffi[email protected] 6 Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904, USA; [email protected] 7 The Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101, USA; [email protected] 8 Sydney Institute for Astronomy, School of Physics, University of Sydney, NSW 2006, Australia; [email protected] * Correspondence: [email protected]; Tel.: +1-212-854-3884 † These authors contributed equally to this work. Academic Editors: Duncan A. Forbes and Ericson D. Lopez Received: 1 July 2017; Accepted: 14 August 2017; Published: 26 August 2017 Abstract: Deep photometric surveys of the Milky Way have revealed diffuse structures encircling our Galaxy far beyond the “classical” limits of the stellar disk.