The Bennett Catalogue
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![Arxiv:0804.4630V1 [Astro-Ph] 29 Apr 2008 I Ehnv20;Ficao 06) Ti Nti Oeas Role This in Is It 2006A)](https://docslib.b-cdn.net/cover/8871/arxiv-0804-4630v1-astro-ph-29-apr-2008-i-ehnv20-ficao-06-ti-nti-oeas-role-this-in-is-it-2006a-158871.webp)
Arxiv:0804.4630V1 [Astro-Ph] 29 Apr 2008 I Ehnv20;Ficao 06) Ti Nti Oeas Role This in Is It 2006A)
DRAFT VERSION NOVEMBER 9, 2018 Preprint typeset using LATEX style emulateapj v. 05/04/06 OPEN CLUSTERS AS GALACTIC DISK TRACERS: I. PROJECT MOTIVATION, CLUSTER MEMBERSHIP AND BULK THREE-DIMENSIONAL KINEMATICS PETER M. FRINCHABOY1,2,3 AND STEVEN R. MAJEWSKI2 Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904-4325, USA Draft version November 9, 2018 ABSTRACT We have begun a survey of the chemical and dynamical properties of the Milky Way disk as traced by open star clusters. In this first contribution, the general goals of our survey are outlined and the strengths and limita- tions of using star clusters as a Galactic disk tracer sample are discussed. We also present medium resolution (R 15,0000) spectroscopy of open cluster stars obtained with the Hydra multi-object spectrographs on the Cerro∼ Tololo Inter-American Observatory 4-m and WIYN 3.5-m telescopes. Here we use these data to deter- mine the radial velocities of 3436 stars in the fields of open clusters within about 3 kpc, with specific attention to stars having proper motions in the Tycho-2 catalog. Additional radial velocity members (without Tycho-2 proper motions) that can be used for future studies of these clusters were also identified. The radial velocities, proper motions, and the angular distance of the stars from cluster center are used to derive cluster member- ship probabilities for stars in each cluster field using a non-parametric approach, and the cluster members so-identified are used, in turn, to derive the reliable bulk three-dimensional motion for 66 of 71 targeted open clusters. -
Messier Plus Marathon Text
Messier Plus Marathon Object List by Wally Brown & Bob Buckner with additional objects by Mike Roos Object Data - Saguaro Astronomy Club Score is most numbered objects in a single night. Tiebreaker is count of un-numbered objects Observer Name Date Address Marathon Obects __________ Tiebreaker Objects ________ SEQ OBJECT TYPE CON R.A. DEC. RISE TRANSIT SET MAG SIZE NOTES TIME M 53 GLOCL COM 1312.9 +1810 7:21 14:17 21:12 7.7 13.0' NGC 5024, !B,vC,iR,vvmbM,st 12.. NGC 5272, !!,eB,vL,vsmbM,st 11.., Lord Rosse-sev dark 1 M 3 GLOCL CVN 1342.2 +2822 7:11 14:46 22:20 6.3 18.0' marks within 5' of center 2 M 5 GLOCL SER 1518.5 +0205 10:17 16:22 22:27 5.7 23.0' NGC 5904, !!,vB,L,eCM,eRi, st mags 11...;superb cluster M 94 GALXY CVN 1250.9 +4107 5:12 13:55 22:37 8.1 14.4'x12.1' NGC 4736, vB,L,iR,vsvmbM,BN,r NGC 6121, Cl,8 or 10 B* in line,rrr, Look for central bar M 4 GLOCL SCO 1623.6 -2631 12:56 17:27 21:58 5.4 36.0' structure M 80 GLOCL SCO 1617.0 -2258 12:36 17:21 22:06 7.3 10.0' NGC 6093, st 14..., Extremely rich and compressed M 62 GLOCL OPH 1701.2 -3006 13:49 18:05 22:21 6.4 15.0' NGC 6266, vB,L,gmbM,rrr, Asymmetrical M 19 GLOCL OPH 1702.6 -2615 13:34 18:06 22:38 6.8 17.0' NGC 6273, vB,L,R,vCM,rrr, One of the most oblate GC 3 M 107 GLOCL OPH 1632.5 -1303 12:17 17:36 22:55 7.8 13.0' NGC 6171, L,vRi,vmC,R,rrr, H VI 40 M 106 GALXY CVN 1218.9 +4718 3:46 13:23 22:59 8.3 18.6'x7.2' NGC 4258, !,vB,vL,vmE0,sbMBN, H V 43 M 63 GALXY CVN 1315.8 +4201 5:31 14:19 23:08 8.5 12.6'x7.2' NGC 5055, BN, vsvB stell. -
Planetary Nebulae
Planetary Nebulae A planetary nebula is a kind of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from old red giant stars late in their lives. The term "planetary nebula" is a misnomer that originated in the 1780s with astronomer William Herschel because when viewed through his telescope, these objects appeared to him to resemble the rounded shapes of planets. Herschel's name for these objects was popularly adopted and has not been changed. They are a relatively short-lived phenomenon, lasting a few tens of thousands of years, compared to a typical stellar lifetime of several billion years. The mechanism for formation of most planetary nebulae is thought to be the following: at the end of the star's life, during the red giant phase, the outer layers of the star are expelled by strong stellar winds. Eventually, after most of the red giant's atmosphere is dissipated, the exposed hot, luminous core emits ultraviolet radiation to ionize the ejected outer layers of the star. Absorbed ultraviolet light energizes the shell of nebulous gas around the central star, appearing as a bright colored planetary nebula at several discrete visible wavelengths. Planetary nebulae may play a crucial role in the chemical evolution of the Milky Way, returning material to the interstellar medium from stars where elements, the products of nucleosynthesis (such as carbon, nitrogen, oxygen and neon), have been created. Planetary nebulae are also observed in more distant galaxies, yielding useful information about their chemical abundances. In recent years, Hubble Space Telescope images have revealed many planetary nebulae to have extremely complex and varied morphologies. -
Spatial Distribution of Galactic Globular Clusters: Distance Uncertainties and Dynamical Effects
Juliana Crestani Ribeiro de Souza Spatial Distribution of Galactic Globular Clusters: Distance Uncertainties and Dynamical Effects Porto Alegre 2017 Juliana Crestani Ribeiro de Souza Spatial Distribution of Galactic Globular Clusters: Distance Uncertainties and Dynamical Effects Dissertação elaborada sob orientação do Prof. Dr. Eduardo Luis Damiani Bica, co- orientação do Prof. Dr. Charles José Bon- ato e apresentada ao Instituto de Física da Universidade Federal do Rio Grande do Sul em preenchimento do requisito par- cial para obtenção do título de Mestre em Física. Porto Alegre 2017 Acknowledgements To my parents, who supported me and made this possible, in a time and place where being in a university was just a distant dream. To my dearest friends Elisabeth, Robert, Augusto, and Natália - who so many times helped me go from "I give up" to "I’ll try once more". To my cats Kira, Fen, and Demi - who lazily join me in bed at the end of the day, and make everything worthwhile. "But, first of all, it will be necessary to explain what is our idea of a cluster of stars, and by what means we have obtained it. For an instance, I shall take the phenomenon which presents itself in many clusters: It is that of a number of lucid spots, of equal lustre, scattered over a circular space, in such a manner as to appear gradually more compressed towards the middle; and which compression, in the clusters to which I allude, is generally carried so far, as, by imperceptible degrees, to end in a luminous center, of a resolvable blaze of light." William Herschel, 1789 Abstract We provide a sample of 170 Galactic Globular Clusters (GCs) and analyse its spatial distribution properties. -
A Photometric and Spectroscopic Study of the Southern Open Clusters Pismis 18, Pismis 19, Ngc 6005, and Ngc 6253 Andre S E
THE ASTRONOMICAL JOURNAL, 116:801È812, 1998 August ( 1998. The American Astronomical Society. All rights reserved. Printed in U.S.A. A PHOTOMETRIC AND SPECTROSCOPIC STUDY OF THE SOUTHERN OPEN CLUSTERS PISMIS 18, PISMIS 19, NGC 6005, AND NGC 6253 ANDRE S E. PIATTI1,2 AND JUAN J. CLARIA 2 Observatorio Astrono mico, Universidad Nacional de Co rdoba, Laprida 854, 5000 Co rdoba, Argentina; andres=oac.uncor.edu, claria=oac.uncor.edu EDUARDO BICA2 Departamento de Astronomia, Universidade Federal do Rio Grande do Sul, C.P. 15051, Porto Alegre, 91500-970, RS, Brazil; bica=if.ufrgs.br DOUG GEISLER Kitt Peak National Observatory, National Optical Astronomy Observatories, P.O. Box 26732, Tucson, AZ 85726; doug=noao.edu AND DANTE MINNITI Lawrence Livermore National Laboratory, L-413, P.O. Box 808, Livermore, CA 94550; dminniti=igpp.llnl.gov Received 1997 October 3; revised 1998 April 24 ABSTRACT CCD observations in the B, V , and I passbands have been used to generate color-magnitude diagrams (CMDs) for the southern open cluster candidates Pismis 18, Pismis 19, and NGC 6005, as well as for the old open cluster NGC 6253. The sample consists of about 1550 stars reaching down to V D 19 mag. From analysis of the CMDs, the physical reality of the three cluster candidates is conÐrmed and their reddening, distance, and age are derived, as well as those of NGC 6253. In addition, integrated spectra for Pismis 18, Pismis 19, and NGC 6253 covering a range from 3500 to 9200A were obtained. The reddening, age, and metallicity of these three clusters were derived from Balmer and Ca II triplet equiva- lent widths by comparing the observed spectra with those of template clusters. -
Central Coast Astronomy Virtual Star Party January 16Th 7Pm Pacific
Central Coast Astronomy Virtual Star Party January 16th 7pm Pacific Welcome to our Virtual Star Gazing session! We’ll be focusing on objects you can see with binoculars or a small telescope, so after our session, you can simply walk outside, look up, and understand what you’re looking at. CCAS President Aurora Lipper and astronomer Kent Wallace will bring you a virtual “tour of the night sky” where you can discover, learn, and ask questions as we go along! All you need is an internet connection. You can use an iPad, laptop, computer or cell phone. When 7pm on Saturday night rolls around, click the link on our website to join our class. CentralCoastAstronomy.org/stargaze Before our session starts: Step 1: Download your free map of the night sky: SkyMaps.com They have it available for Northern and Southern hemispheres. Step 2: Print out this document and use it to take notes during our time on Saturday. This document highlights the objects we will focus on in our session together. Celestial Objects: Moon: The moon is 3 days past new, which is really good for star gazing. Be sure to look at the moon tonight with your naked eyes and/or binoculars! Mercury is rising into the western sky and may be a good target near the end of the month. Mars is up high but is shrinking in size as the weeks progress. *Image credit: all astrophotography images are courtesy of NASA unless otherwise noted. All planetarium images are courtesy of Stellarium. Central Coast Astronomy CentralCoastAstronomy.org Page 1 Main Focus for the Session: 1. -
Open Clusters in Gaia
Sede Amministrativa: Università degli Studi di Padova Dipartimento di Fisica e Astronomia “G. Galilei” Corso di Dottorato di Ricerca in Astronomia Ciclo XXX OPEN CLUSTERS IN GAIA ERA Coordinatore: Ch.mo Prof. Giampaolo Piotto Supervisore: Dr.ssa Antonella Vallenari Dottorando: Francesco Pensabene i Abstract Context. Open clusters (OCs) are optimal tracers of the Milky Way disc. They are observed at every distance from the Galactic center and their ages cover the entire lifespan of the disc. The actual OC census contain more than 3000 objects, but suffers of incom- pleteness out of the solar neighborhood and of large inhomogeneity in the parameter deter- minations present in literature. Both these aspects will be improved by the on-going space mission Gaia . In the next years Gaia will produce the most precise three-dimensional map of the Milky Way by surveying other than 1 billion of stars. For those stars Gaia will provide extremely precise measure- ment of proper motions, parallaxes and brightness. Aims. In this framework we plan to take advantage of the first Gaia data release, while preparing for the coming ones, to: i) move the first steps towards building a homogeneous data base of OCs with the high quality Gaia astrometry and photometry; ii) build, improve and test tools for the analysis of large sample of OCs; iii) use the OCs to explore the prop- erties of the disc in the solar neighborhood. Methods and Data. Using ESO archive data, we analyze the photometry and derive physical parameters, comparing data with synthetic populations and luminosity functions, of three clusters namely NGC 2225, NGC 6134 and NGC 2243. -
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). -
Globular Clusters in the Inner Galaxy Classified from Dynamical Orbital
MNRAS 000,1{17 (2019) Preprint 14 November 2019 Compiled using MNRAS LATEX style file v3.0 Globular clusters in the inner Galaxy classified from dynamical orbital criteria Angeles P´erez-Villegas,1? Beatriz Barbuy,1 Leandro Kerber,2 Sergio Ortolani3 Stefano O. Souza 1 and Eduardo Bica,4 1Universidade de S~aoPaulo, IAG, Rua do Mat~ao 1226, Cidade Universit´aria, S~ao Paulo 05508-900, Brazil 2Universidade Estadual de Santa Cruz, Rodovia Jorge Amado km 16, Ilh´eus 45662-000, Brazil 3Dipartimento di Fisica e Astronomia `Galileo Galilei', Universit`adi Padova, Vicolo dell'Osservatorio 3, Padova, I-35122, Italy 4Universidade Federal do Rio Grande do Sul, Departamento de Astronomia, CP 15051, Porto Alegre 91501-970, Brazil Accepted XXX. Received YYY; in original form ZZZ ABSTRACT Globular clusters (GCs) are the most ancient stellar systems in the Milky Way. There- fore, they play a key role in the understanding of the early chemical and dynamical evolution of our Galaxy. Around 40% of them are placed within ∼ 4 kpc from the Galactic center. In that region, all Galactic components overlap, making their disen- tanglement a challenging task. With Gaia DR2, we have accurate absolute proper mo- tions for the entire sample of known GCs that have been associated with the bulge/bar region. Combining them with distances, from RR Lyrae when available, as well as ra- dial velocities from spectroscopy, we can perform an orbital analysis of the sample, employing a steady Galactic potential with a bar. We applied a clustering algorithm to the orbital parameters apogalactic distance and the maximum vertical excursion from the plane, in order to identify the clusters that have high probability to belong to the bulge/bar, thick disk, inner halo, or outer halo component. -
Astronomy & Astrophysics Integrated Photometric Characteristics of Galactic Open Star Clusters
A&A 388, 158–167 (2002) Astronomy DOI: 10.1051/0004-6361:20020450 & c ESO 2002 Astrophysics Integrated photometric characteristics of galactic open star clusters S. Lata1,A.K.Pandey1, R. Sagar1,2, and V. Mohan1 1 State Observatory, Manora peak, Nainital 263129, Uttaranchal, India e-mail: sneh, pandey, sagar, [email protected] 2 Indian Institute of Astrophysics, Bangalore 560034, India Received 19 November 2001 / Accepted 19 February 2002 Abstract. Integrated UBVRI photometric parameters of 140 galactic open clusters have been computed. Integrated I(V − R)0 and I(V − I)0 colours as well as integrated parameters for 71 star clusters have been obtained for the first time. These, in combination with published data, altogether 352 objects, are used to study the integrated photometric characteristics of the galactic open clusters. The I(MV ) values range from −9.0to 4 −1.0 mag corresponding to a range in total mass of the star clusters from ∼25 to 4×10 M . The integrated colours have a relatively narrow range, e.g., I(B − V )0 varies from −0.4 to 1.2 mag. The scatter in integrated colours at a given integrated magnitude can be understood in terms of differences in fraction of red giants/supergiants in the clusters. The observed integrated magnitudes and colours agree with the synthetic ones, except the dependences of I(V − R)0 and I(V − I)0 colours for clusters younger than ∼100 Myrs and also of the integrated magnitudes of oldest clusters. The large sample provides the most accurate age dependence of integrated magnitudes and colours determined so far. -
Download the 2016 Spring Deep-Sky Challenge
Deep-sky Challenge 2016 Spring Southern Star Party Explore the Local Group Bonnievale, South Africa Hello! And thanks for taking up the challenge at this SSP! The theme for this Challenge is Galaxies of the Local Group. I’ve written up some notes about galaxies & galaxy clusters (pp 3 & 4 of this document). Johan Brink Peter Harvey Late-October is prime time for galaxy viewing, and you’ll be exploring the James Smith best the sky has to offer. All the objects are visible in binoculars, just make sure you’re properly dark adapted to get the best view. Galaxy viewing starts right after sunset, when the centre of our own Milky Way is visible low in the west. The edge of our spiral disk is draped along the horizon, from Carina in the south to Cygnus in the north. As the night progresses the action turns north- and east-ward as Orion rises, drawing the Milky Way up with it. Before daybreak, the Milky Way spans from Perseus and Auriga in the north to Crux in the South. Meanwhile, the Large and Small Magellanic Clouds are in pole position for observing. The SMC is perfectly placed at the start of the evening (it culminates at 21:00 on November 30), while the LMC rises throughout the course of the night. Many hundreds of deep-sky objects are on display in the two Clouds, so come prepared! Soon after nightfall, the rich galactic fields of Sculptor and Grus are in view. Gems like Caroline’s Galaxy (NGC 253), the Black-Bottomed Galaxy (NGC 247), the Sculptor Pinwheel (NGC 300), and the String of Pearls (NGC 55) are keen to be viewed. -
![Arxiv:1911.09125V2 [Astro-Ph.SR] 23 Jun 2020 Maccarone Et Al](https://docslib.b-cdn.net/cover/9983/arxiv-1911-09125v2-astro-ph-sr-23-jun-2020-maccarone-et-al-1079983.webp)
Arxiv:1911.09125V2 [Astro-Ph.SR] 23 Jun 2020 Maccarone Et Al
Draft version June 25, 2020 Typeset using LATEX twocolumn style in AASTeX63 A Dynamical Survey of Stellar-Mass Black Holes in 50 Milky Way Globular Clusters Newlin C. Weatherford,1, 2 Sourav Chatterjee,3 Kyle Kremer,1, 2 Frederic A. Rasio,1, 2 1Department of Physics & Astronomy, Northwestern University, Evanston, IL 60208, USA 2Center for Interdisciplinary Exploration & Research in Astrophysics (CIERA), Northwestern University, Evanston, IL 60208, USA 3Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India ABSTRACT Recent numerical simulations of globular clusters (GCs) have shown that stellar-mass black holes (BHs) play a fundamental role in driving cluster evolution and shaping their present-day structure. Rapidly mass-segregating to the center of GCs, BHs act as a dynamical energy source via repeated super-elastic scattering, delaying onset of core collapse and limiting mass segregation for visible stars. While recent discoveries of BH candidates in Galactic and extragalactic GCs have further piqued inter- est in BH-mediated cluster dynamics, numerical models show that even if significant BH populations remain in today's GCs, they are not typically in directly detectable configurations. We demonstrated in Weatherford et al.(2018) that an anti-correlation between a suitable measure of mass segregation (∆) in observable stellar populations and the number of retained BHs in GC models can be applied to indirectly probe BH populations in real GCs. Here, we estimate the number and total mass of BHs in 50 Milky Way GCs from the ACS Globular Cluster Survey. For each GC, ∆ is measured between observed main sequence populations and fed into correlations between ∆ and BH retention found in our CMC Cluster Catalog's models.