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Clusters of Galaxies…
Budapest University, MTA-Eötvös François Mernier …and the surprisesoftheir spectacularhotatmospheres Clusters ofgalaxies… K complex ) ⇤ Fe ) α [email protected] - Wallon Super - Wallon [email protected] Fe XXVI (Ly (/ Fe XXIV) L complex ) ) (incl. Ne) α α ) Fe ) ) α ) α α ) ) ) ) α ⇥ ) ) ) α α α α α α Si XIV (Ly Mg XII (Ly Ni XXVII / XXVIII Fe XXV (He S XVI (Ly O VIII (Ly Si XIII (He S XV (He Ca XIX (He Ca XX (Ly Fe XXV (He Cr XXIII (He Ar XVII (He Ar XVIII (Ly Mn XXIV (He Ca XIX / XX Yo u are h ere ! 1 km = 103 m Yo u are h ere ! (somewhere behind…) 107 m Yo u are h ere ! (and this is the Moon) 109 m ≃3.3 light seconds Yo u are h ere ! 1012 m ≃55.5 light minutes 1013 m 1014 m Yo u are h ere ! ≃4 light days 1013 m Yo u are h ere ! 1014 m 1017 m ≃10.6 light years 1021 m Yo u are h ere ! ≃106 000 light years 1 million ly Yo u are h ere ! The Local Group Andromeda (M31) 1 million ly Yo u are h ere ! The Local Group Triangulum (M33) 1 million ly Yo u are h ere ! The Local Group 10 millions ly The Virgo Supercluster Virgo cluster 10 millions ly The Virgo Supercluster M87 Virgo cluster 10 millions ly The Virgo Supercluster 2dFGRS Survey The large scale structure of the universe Abell 2199 (429 000 000 light years) Abell 2029 (1.1 billion light years) Abell 2029 (1.1 billion light years) Abell 1689 Abell 1689 (2.2 billion light years) Les amas de galaxies 53 Light emits at optical “colors”… …but also in infrared, radio, …and X-ray! Light emits at optical “colors”… …but also in infrared, radio, …and X-ray! Light emits at optical “colors”… -
Arxiv:1612.03165V3 [Astro-Ph.HE] 12 Sep 2017 – 2 –
The second catalog of flaring gamma-ray sources from the Fermi All-sky Variability Analysis S. Abdollahi1, M. Ackermann2, M. Ajello3;4, A. Albert5, L. Baldini6, J. Ballet7, G. Barbiellini8;9, D. Bastieri10;11, J. Becerra Gonzalez12;13, R. Bellazzini14, E. Bissaldi15, R. D. Blandford16, E. D. Bloom16, R. Bonino17;18, E. Bottacini16, J. Bregeon19, P. Bruel20, R. Buehler2;21, S. Buson12;22, R. A. Cameron16, M. Caragiulo23;15, P. A. Caraveo24, E. Cavazzuti25, C. Cecchi26;27, A. Chekhtman28, C. C. Cheung29, G. Chiaro11, S. Ciprini25;26, J. Conrad30;31;32, D. Costantin11, F. Costanza15, S. Cutini25;26, F. D'Ammando33;34, F. de Palma15;35, A. Desai3, R. Desiante17;36, S. W. Digel16, N. Di Lalla6, M. Di Mauro16, L. Di Venere23;15, B. Donaggio10, P. S. Drell16, C. Favuzzi23;15, S. J. Fegan20, E. C. Ferrara12, W. B. Focke16, A. Franckowiak2, Y. Fukazawa1, S. Funk37, P. Fusco23;15, F. Gargano15, D. Gasparrini25;26, N. Giglietto23;15, M. Giomi2;59, F. Giordano23;15, M. Giroletti33, T. Glanzman16, D. Green13;12, I. A. Grenier7, J. E. Grove29, L. Guillemot38;39, S. Guiriec12;22, E. Hays12, D. Horan20, T. Jogler40, G. J´ohannesson41, A. S. Johnson16, D. Kocevski12;42, M. Kuss14, G. La Mura11, S. Larsson43;31, L. Latronico17, J. Li44, F. Longo8;9, F. Loparco23;15, M. N. Lovellette29, P. Lubrano26, J. D. Magill13, S. Maldera17, A. Manfreda6, M. Mayer2, M. N. Mazziotta15, P. F. Michelson16, W. Mitthumsiri45, T. Mizuno46, M. E. Monzani16, A. Morselli47, I. V. Moskalenko16, M. Negro17;18, E. Nuss19, T. Ohsugi46, N. Omodei16, M. Orienti33, E. -
Arxiv:2104.03323V2 [Astro-Ph.SR] 9 Apr 2021 Pending on the Metallicity and Modeling Assumptions (E.G., Lar- Son & Starrfield 1971; Oey & Clarke 2005)
Astronomy & Astrophysics manuscript no. main ©ESO 2021 April 12, 2021 The Tarantula Massive Binary Monitoring V. R 144 – a wind-eclipsing binary with a total mass & 140 M * T. Shenar1, H. Sana1, P. Marchant1, B. Pablo2, N. Richardson3, A. F. J. Moffat4, T. Van Reeth1, R. H. Barbá5, D. M. Bowman1, P. Broos6, P. A. Crowther7, J. S. Clark8†, A. de Koter9, S. E. de Mink10; 9; 11, K. Dsilva1, G. Gräfener12, I. D. Howarth13, N. Langer12, L. Mahy1; 14, J. Maíz Apellániz15, A. M. T. Pollock7, F. R. N. Schneider16; 17, L. Townsley6, and J. S. Vink18 (Affiliations can be found after the references) Received March 02, 2021; accepted April 06, 2021 ABSTRACT Context. The evolution of the most massive stars and their upper-mass limit remain insufficiently constrained. Very massive stars are characterized by powerful winds and spectroscopically appear as hydrogen-rich Wolf-Rayet (WR) stars on the main sequence. R 144 is the visually brightest WR star in the Large Magellanic Cloud (LMC). R 144 was reported to be a binary, making it potentially the most massive binary thus observed. However, the orbit and properties of R 144 are yet to be established. Aims. Our aim is to derive the physical, atmospheric, and orbital parameters of R 144 and interpret its evolutionary status. Methods. We perform a comprehensive spectral, photometric, orbital, and polarimetric analysis of R 144. Radial velocities are measured via cross- correlation. Spectral disentangling is performed using the shift-and-add technique. We use the Potsdam Wolf-Rayet (PoWR) code for the spectral analysis. We further present X-ray and optical light-curves of R 144, and analyse the latter using a hybrid model combining wind eclipses and colliding winds to constrain the orbital inclination i. -
Filter Performance Comparisons for Some Common Nebulae
Filter Performance Comparisons For Some Common Nebulae By Dave Knisely Light Pollution and various “nebula” filters have been around since the late 1970’s, and amateurs have been using them ever since to bring out detail (and even some objects) which were difficult to impossible to see before in modest apertures. When I started using them in the early 1980’s, specific information about which filter might work on a given object (or even whether certain filters were useful at all) was often hard to come by. Even those accounts that were available often had incomplete or inaccurate information. Getting some observational experience with the Lumicon line of filters helped, but there were still some unanswered questions. I wondered how the various filters would rank on- average against each other for a large number of objects, and whether there was a “best overall” filter. In particular, I also wondered if the much-maligned H-Beta filter was useful on more objects than the two or three targets most often mentioned in publications. In the summer of 1999, I decided to begin some more comprehensive observations to try and answer these questions and determine how to best use these filters overall. I formulated a basic survey covering a moderate number of emission and planetary nebulae to obtain some statistics on filter performance to try to address the following questions: 1. How do the various filter types compare as to what (on average) they show on a given nebula? 2. Is there one overall “best” nebula filter which will work on the largest number of objects? 3. -
Supernova Shocks in Molecular Clouds: Velocity Distribution of Molecular Hydrogen William T
Draft version September 6, 2019 Typeset using LATEX preprint2 style in AASTeX63 Supernova Shocks in Molecular Clouds: Velocity Distribution of Molecular Hydrogen William T. Reach,1 Le Ngoc Tram,1 Matthew Richter,2 Antoine Gusdorf,3 Curtis DeWitt,1 1Universities Space Research Association, MS 232-11, Moffett Field, CA 94035, USA 2University of California, Davis, CA USA 3Observatoire de Paris, Ecole´ normale sup´erieure, Sorbonne Universit´e,CNRS, LERMA, 75005 Paris, France ABSTRACT Supernovae from core-collapse of massive stars drive shocks into the molecular clouds from which the stars formed. Such shocks affect future star formation from the molecu- lar clouds, and the fast-moving, dense gas with compressed magnetic fields is associated with enhanced cosmic rays. This paper presents new theoretical modeling, using the Paris-Durham shock model, and new observations at high spectral resolution, using the Stratospheric Observatory for Infrared Astronomy (SOFIA), of the H2 S(5) pure rota- tional line from molecular shocks in the supernova remnant IC 443. We generate MHD models for non-steady-state shocks driven by the pressure of the IC 443 blast wave into gas of densities 103 to 105 cm−3. We present the first detailed derivation of the shape of the velocity profile for emission from H2 lines behind such shocks, taking into account the shock age, preshock density, and magnetic field. For preshock densities 103{105 −3 cm , the H2 emission arises from layers that extend 0.01{0.0003 pc behind the shock, respectively. The predicted shifts of line centers, and the line widths, of the H2 lines range from 20{2, and 30{4 km s−1, respectively. -
How to Make $1000 with Your Telescope! – 4 Stargazers' Diary
Fort Worth Astronomical Society (Est. 1949) February 2010 : Astronomical League Member Club Calendar – 2 Opportunities & The Sky this Month – 3 How to Make $1000 with your Telescope! – 4 Astronaut Sally Ride to speak at UTA – 4 Aurgia the Charioteer – 5 Stargazers’ Diary – 6 Bode’s Galaxy by Steve Tuttle 1 February 2010 Sunday Monday Tuesday Wednesday Thursday Friday Saturday 1 2 3 4 5 6 Algol at Minima Last Qtr Moon Æ 5:48 am 11:07 pm Top ten binocular deep-sky objects for February: M35, M41, M46, M47, M50, M93, NGC 2244, NGC 2264, NGC 2301, NGC 2360 Top ten deep-sky objects for February: M35, M41, M46, M47, M50, M93, NGC 2261, NGC 2362, NGC 2392, NGC 2403 7 8 9 10 11 12 13 Algol at Minima Morning sports a Moon at Apogee New Moon Æ super thin crescent (252,612 miles) 8:51 am 7:56 pm Moon 8:00 pm 3RF Star Party Make use of the New Moon Weekend for . better viewing at the Dark Sky Site See Notes Below New Moon New Moon Weekend Weekend 14 15 16 17 18 19 20 Presidents Day 3RF Star Party Valentine’s Day FWAS Traveler’s Guide Meeting to the Planets UTA’s Maverick Clyde Tombaugh Ranger 8 returns Normal Room premiers on Speakers Series discovered Pluto photographs and NatGeo 7pm Sally Ride “Fat Tuesday” Ash Wednesday 80 years ago. impacts Moon. 21 22 23 24 25 26 27 Algol at Minima First Qtr Moon Moon at Perigee Å (222,345 miles) 6:42 pm 12:52 am 4 pm {Low in the NW) Algol at Minima Æ 9:43 pm Challenge binary star for month: 15 Lyncis (Lynx) Challenge deep-sky object for month: IC 443 (Gemini) Notable carbon star for month: BL Orionis (Orion) 28 Notes: Full Moon Look for a very thin waning crescent moon perched just above and slightly right of tiny Mercury on the morning of 10:38 pm Feb. -
Expected Differences Between AGB Stars in the LMC and the SMC Due to Differences in Chemical Composition
New Views of the Magellanic Clouds fA U Symposium, Vol. 190, 1999 Y.-H. Chu, N.B. Suntzef], J.E. Hesser, and D.A. Bohlender, eds. Expected Differences between AGB Stars in the LMC and the SMC Due to Differences in Chemical Composition Ju. Frantsman Astronomical Institute, Latvian University, Raina Blvd. 19, Riga, LV-1586, LATVIA Abstract. Certain aspects of the AGB population, such as the relative number of M and N stars, the mass loss rates, and the initial masses of carbon- oxygen cores, depend on the initial heavy element abundance Z. I have calculated synthetic populations of AGB stars for different initial Z values taking into consideration the evolution of single and close binary stars. I present the results of population syntheses of AGB stars in clusters as a function of different initial chemical compositions. The relation for the tip luminosity of AGB stars versus cluster age as a function of Z is presented and is used to determine the ages for a number of clusters in the LMC and the SMC, including clusters with no previous age determinations. Population simulations show that for low heavy element abundance (Z = 0.001) few M stars are formed with respect to the number of carbon stars. However, the total number of all AGB stars in clusters is not affected by the initial chemical composition. As a result of the evolution of close binary components after the mass exchange, an increase in the range of limiting values of the thermal pulsing AGB star luminosities is expected. The difference between the maximum luminosity on the AGB of single star and the luminosity of a star after a mass exchange event in a close binary system may be as great as 1 magnitude for very young clusters. -
Guide Du Ciel Profond
Guide du ciel profond Olivier PETIT 8 mai 2004 2 Introduction hjjdfhgf ghjfghfd fg hdfjgdf gfdhfdk dfkgfd fghfkg fdkg fhdkg fkg kfghfhk Table des mati`eres I Objets par constellation 21 1 Androm`ede (And) Andromeda 23 1.1 Messier 31 (La grande Galaxie d'Androm`ede) . 25 1.2 Messier 32 . 27 1.3 Messier 110 . 29 1.4 NGC 404 . 31 1.5 NGC 752 . 33 1.6 NGC 891 . 35 1.7 NGC 7640 . 37 1.8 NGC 7662 (La boule de neige bleue) . 39 2 La Machine pneumatique (Ant) Antlia 41 2.1 NGC 2997 . 43 3 le Verseau (Aqr) Aquarius 45 3.1 Messier 2 . 47 3.2 Messier 72 . 49 3.3 Messier 73 . 51 3.4 NGC 7009 (La n¶ebuleuse Saturne) . 53 3.5 NGC 7293 (La n¶ebuleuse de l'h¶elice) . 56 3.6 NGC 7492 . 58 3.7 NGC 7606 . 60 3.8 Cederblad 211 (N¶ebuleuse de R Aquarii) . 62 4 l'Aigle (Aql) Aquila 63 4.1 NGC 6709 . 65 4.2 NGC 6741 . 67 4.3 NGC 6751 (La n¶ebuleuse de l’œil flou) . 69 4.4 NGC 6760 . 71 4.5 NGC 6781 (Le nid de l'Aigle ) . 73 TABLE DES MATIERES` 5 4.6 NGC 6790 . 75 4.7 NGC 6804 . 77 4.8 Barnard 142-143 (La tani`ere noire) . 79 5 le B¶elier (Ari) Aries 81 5.1 NGC 772 . 83 6 le Cocher (Aur) Auriga 85 6.1 Messier 36 . 87 6.2 Messier 37 . 89 6.3 Messier 38 . -
A Basic Requirement for Studying the Heavens Is Determining Where In
Abasic requirement for studying the heavens is determining where in the sky things are. To specify sky positions, astronomers have developed several coordinate systems. Each uses a coordinate grid projected on to the celestial sphere, in analogy to the geographic coordinate system used on the surface of the Earth. The coordinate systems differ only in their choice of the fundamental plane, which divides the sky into two equal hemispheres along a great circle (the fundamental plane of the geographic system is the Earth's equator) . Each coordinate system is named for its choice of fundamental plane. The equatorial coordinate system is probably the most widely used celestial coordinate system. It is also the one most closely related to the geographic coordinate system, because they use the same fun damental plane and the same poles. The projection of the Earth's equator onto the celestial sphere is called the celestial equator. Similarly, projecting the geographic poles on to the celest ial sphere defines the north and south celestial poles. However, there is an important difference between the equatorial and geographic coordinate systems: the geographic system is fixed to the Earth; it rotates as the Earth does . The equatorial system is fixed to the stars, so it appears to rotate across the sky with the stars, but of course it's really the Earth rotating under the fixed sky. The latitudinal (latitude-like) angle of the equatorial system is called declination (Dec for short) . It measures the angle of an object above or below the celestial equator. The longitud inal angle is called the right ascension (RA for short). -
Remerciements – Unité 1
TVO ILC SNC1D Remerciements Remerciements – Unité 1 Graphs, diagrams, illustrations, images in this course, unless otherwise specified, are ILC created, Copyright © 2018 The Ontario Educational Communications Authority. All rights reserved. Intro Video, Copyright © 2018 The Ontario Educational Communications Authority. All rights reserved. All title artwork and graphics, unless otherwise specified, Copyright © 2018The Ontario Educational Communications Authority. All rights reserved. Logo: Science Presse , Agence Science-Presse, URL: https://www.sciencepresse.qc.ca/, Accessed 14/01/2019. Logo: Curium, Curium, URL: https://curiummag.com/wp-content/uploads/2017/10/logo_ curium-web.png, Accessed 14/01/2019. Logo: Science Étonnante, David Louapre, URL: https://sciencetonnante.wordpress.com/, Accessed 20/03/2018, © 2018 HowStuffWorks, a division of InfoSpace Holdings LLC, a System1 Company. Blog, blogging and blogglers theme, djvstock/iStock/Getty Images Logo: Wordpress, WordPress.com, Automattic Inc., URL: https://wordpress.com/, Accessed 20/03/2018, © The WordPress Foundation. Logo: Wix, Wix.com, Inc., URL: https://static.wixstatic.com/ media/9ab0d1_39d56f21398048df8af89aab0cec67b8~mv1.png, Accessed 14/01/2019. Logo: Blogger, Blogger, Inc., ZyMOS, URL: https://commons.wikimedia.org/wiki/File:Blogger. svg, Accessed 20/03/2018, © Google LLC. HOME A film by Yann Arthus-Bertrand, GoodPlanet Foundation, Europacorp and Elzévir Films, URL: https://www.youtube.com/watch?v=GItD10Joaa0, Published 04/02/2009, Accessed 20/04/2018, Courtesy of the GoodPlanet -
Cfa in the News ~ Week Ending 3 January 2010
Wolbach Library: CfA in the News ~ Week ending 3 January 2010 1. New social science research from G. Sonnert and co-researchers described, Science Letter, p40, Tuesday, January 5, 2010 2. 2009 in science and medicine, ROGER SCHLUETER, Belleville News Democrat (IL), Sunday, January 3, 2010 3. 'Science, celestial bodies have always inspired humankind', Staff Correspondent, Hindu (India), Tuesday, December 29, 2009 4. Why is Carpenter defending scientists?, The Morning Call, Morning Call (Allentown, PA), FIRST ed, pA25, Sunday, December 27, 2009 5. CORRECTIONS, OPINION BY RYAN FINLEY, ARIZONA DAILY STAR, Arizona Daily Star (AZ), FINAL ed, pA2, Saturday, December 19, 2009 6. We see a 'Super-Earth', TOM BEAL; TOM BEAL, ARIZONA DAILY STAR, Arizona Daily Star, (AZ), FINAL ed, pA1, Thursday, December 17, 2009 Record - 1 DIALOG(R) New social science research from G. Sonnert and co-researchers described, Science Letter, p40, Tuesday, January 5, 2010 TEXT: "In this paper we report on testing the 'rolen model' and 'opportunity-structure' hypotheses about the parents whom scientists mentioned as career influencers. According to the role-model hypothesis, the gender match between scientist and influencer is paramount (for example, women scientists would disproportionately often mention their mothers as career influencers)," scientists writing in the journal Social Studies of Science report (see also ). "According to the opportunity-structure hypothesis, the parent's educational level predicts his/her probability of being mentioned as a career influencer (that ism parents with higher educational levels would be more likely to be named). The examination of a sample of American scientists who had received prestigious postdoctoral fellowships resulted in rejecting the role-model hypothesis and corroborating the opportunity-structure hypothesis. -
The Role of Evolutionary Age and Metallicity in the Formation of Classical Be Circumstellar Disks 11
< * - - *" , , Source of Acquisition NASA Goddard Space Flight Center THE ROLE OF EVOLUTIONARY AGE AND METALLICITY IN THE FORMATION OF CLASSICAL BE CIRCUMSTELLAR DISKS 11. ASSESSING THE TRUE NATURE OF CANDIDATE DISK SYSTEMS J.P. WISNIEWSKI"~'~,K.S. BJORKMAN~'~,A.M. MAGALH~ES~",J.E. BJORKMAN~,M.R. MEADE~, & ANTONIOPEREYRA' Draft version November 27, 2006 ABSTRACT Photometric 2-color diagram (2-CD) surveys of young cluster populations have been used to identify populations of B-type stars exhibiting excess Ha emission. The prevalence of these excess emitters, assumed to be "Be stars". has led to the establishment of links between the onset of disk formation in classical Be stars and cluster age and/or metallicity. We have obtained imaging polarization observations of six SMC and six LMC clusters whose candidate Be populations had been previously identified via 2-CDs. The interstellar polarization (ISP). associated with these data has been identified to facilitate an examination of the circumstellar environments of these candidate Be stars via their intrinsic ~olarization signatures, hence determine the true nature of these objects. We determined that the ISP associated with the SMC cluster NGC 330 was characterized by a modified Serkowski law with a A,,, of -4500A, indicating the presence of smaller than average dust grains. The morphology of the ISP associated with the LMC cluster NGC 2100 suggests that its interstellar environment is characterized by a complex magnetic field. Our intrinsic polarization results confirm the suggestion of Wisniewski et al. that a substantial number of bona-fide classical Be stars are present in clusters of age 5-8 Myr.