Astronomical Tests of General Relativity
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The Star Newsletter
THE HOT STAR NEWSLETTER ? An electronic publication dedicated to A, B, O, Of, LBV and Wolf-Rayet stars and related phenomena in galaxies ? No. 70 2002 July-August http://www.astro.ugto.mx/∼eenens/hot/ editor: Philippe Eenens http://www.star.ucl.ac.uk/∼hsn/index.html [email protected] ftp://saturn.sron.nl/pub/karelh/uploads/wrbib/ Contents of this newsletter Call for Data . 1 Abstracts of 12 accepted papers . 2 Abstracts of 2 submitted papers . 10 Abstracts of 6 proceedings papers . 11 Jobs .......................................................................13 Meetings ...................................................................14 Call for Data The multiplicity of 9 Sgr G. Rauw and H. Sana Institut d’Astrophysique, Universit´ede Li`ege,All´eedu 6 Aoˆut, BˆatB5c, B-4000 Li`ege(Sart Tilman), Belgium e-mail: [email protected], [email protected] The non-thermal radio emission observed for a number of O and WR stars implies the presence of a small population of relativistic electrons in the winds of these objects. Electrons could be accelerated to relativistic velocities either in the shock region of a colliding wind binary (Eichler & Usov 1993, ApJ 402, 271) or in the shocks due to intrinsic wind instabilities of a single star (Chen & White 1994, Ap&SS 221, 259). Dougherty & Williams (2000, MNRAS 319, 1005) pointed out that 7 out of 9 WR stars with non-thermal radio emission are in fact binary systems. This result clearly supports the colliding wind scenario. In the present issue of the Hot Star Newsletter, we announce the results of a multi-wavelength campaign on the O4 V star 9 Sgr (= HD 164794; see the abstract by Rauw et al.). -
The Schwarzschild Metric and Applications 1
The Schwarzschild Metric and Applications 1 Analytic solutions of Einstein's equations are hard to come by. It's easier in situations that e hibit symmetries. 1916: Karl Schwarzschild sought the metric describing the static, spherically symmetric spacetime surrounding a spherically symmetric mass distribution. A static spacetime is one for which there exists a time coordinate t such that i' all the components of g are independent of t ii' the line element ds( is invariant under the transformation t -t A spacetime that satis+es (i) but not (ii' is called stationary. An example is a rotating azimuthally symmetric mass distribution. The metric for a static spacetime has the form where xi are the spatial coordinates and dl( is a time*independent spatial metric. -ross-terms dt dxi are missing because their presence would violate condition (ii'. 23ote: The Kerr metric, which describes the spacetime outside a rotating ( axisymmetric mass distribution, contains a term ∝ dt d.] To preser)e spherical symmetry& dl( can be distorted from the flat-space metric only in the radial direction. In 5at space, (1) r is the distance from the origin and (2) 6r( is the area of a sphere. Let's de+ne r such that (2) remains true but (1) can be violated. Then, A,xi' A,r) in cases of spherical symmetry. The Ricci tensor for this metric is diagonal, with components S/ 10.1 /rimes denote differentiation with respect to r. The region outside the spherically symmetric mass distribution is empty. 9 The vacuum Einstein equations are R = 0. To find A,r' and B,r'# (. -
Assaj V2 N4 1930-Jan
ijtlJt Journal {If tl]t J\.strauamital ~ add!,! af ~ autb J\.frita. Vol. II. JANUARY, 1930. No.4. Astronomical Society of South Africa~ "' AT HOME" TO VISITING ASTRONOMERS OF THE BRITISH ASSOCIATION. July 26, 1929, will long be remembered in the annals of the Astronomical Society of South Africa, for on the evening of that day it was "At Home" at the Oddfellows' Hall, Plein Street, Cape Town, to the visiting astronomers who were attending the meetings of the British Association. The chair was taken by Mr. A. W. Long, President of the Society, who, in opening the proceedings, said: This gathering of the Astronomical Society of South Africa has been arranged to enable the members to greet the distinguished astronomers and other eminent scien tists interested in astronomy who are visiting South Africa in connection with the meetings of the British Association. We have with us to-night Sir Frank Dyson, the Astronomer Royal; Professor Eddington, Director of the Cambridge University Observatory; Professor Fowl~r, Yarrow Research Professor of the Royal Society; Pro fessor Chapman, of the Imperial College of Science; Professor De Sitter, Director of the Leiden Observatory; Dr. Guthnick, Director of the Berlin-Babelsberg Obser vatory; Dr. K110x-Shaw, Director of the Radcliffe Observatory; Mr. Greaves, of the Greenwich Observa tory; Mr. Wrigley, of the Edinburgh Observatory; Dr. Aston, of Cambridge, and I am pleased to say that at a later stage Lord Rayleigh will also be here. In the name of the Society I extend to these gentlemen a very hearty welcome. We have been familiar with them for a very long time by name, and through their scientific attainments; now we are delighted to have the honour of meeting them in person. -
Intentos Argentinos Para Probar La Teor´Ia De La Relatividad
Asociaci´on Argentina de Astronom´ıa BAAA, Vol. 50, 2007 G. Dubner, M. Rovira, A. Piatti & F. A. Bareilles, eds. PRESENTACION´ ORAL Intentos argentinos para probar la Teor´ıa de la Relatividad Santiago Paolantonio1 & Edgardo R. Minitti2 (1) Museo Astron´omico Sarmiento-Gould, Observatorio Astron´omico, Universidad Nacional de C´ordoba, Argentina (2) Observatorio Astron´omico, Universidad Nacional de C´ordoba, Argentina Abstract. Astrophysics research at the Argentinean National Observa- tory (Cordoba) began during the period when Dr. Charles Perrine was its Director (1909-1936). In 1911 Perrine was invited by Dr. Freundlich (Berlin Observatory) to carry out observations in Brazil during the solar eclipse that would take place on October 10, 1912, with the aim of verify- ing Einstein’s theory of relativity. With numerous instruments specially designed and constructed in Cordoba, the expedition took place. How- ever, an inopportune rain made fail all the project. Poor weather condi- tions made also fail two new attempts, one in Teodesy (Ukraine; August 21, 1914), and the other in Tucacas (Venezuela; February 3, 1916). Suc- cessful observations and verification of Einstein’s predictions finally took place in 1919, during an eclipse observed in Brazil. The Argentinean Observatory was unfortunately absent in such opportunity. Resumen. Durante la direcci´on del Dr. Charles Perrine (1909-1936) se inician en el Observatorio Nacional Argentino los trabajos relacionados con la Astrof´ısica. En 1911, Perrine es contactado por el Dr. Freundlich del Observatorio de Berl´ın, quien le propone realizar observaciones para verificar la Teor´ıa de la Relatividad en el eclipse del 10 de octubre de 1912 que ocurrir´ıa en Brasil. -
Former Fellows Biographical Index Part
Former Fellows of The Royal Society of Edinburgh 1783 – 2002 Biographical Index Part Two ISBN 0 902198 84 X Published July 2006 © The Royal Society of Edinburgh 22-26 George Street, Edinburgh, EH2 2PQ BIOGRAPHICAL INDEX OF FORMER FELLOWS OF THE ROYAL SOCIETY OF EDINBURGH 1783 – 2002 PART II K-Z C D Waterston and A Macmillan Shearer This is a print-out of the biographical index of over 4000 former Fellows of the Royal Society of Edinburgh as held on the Society’s computer system in October 2005. It lists former Fellows from the foundation of the Society in 1783 to October 2002. Most are deceased Fellows up to and including the list given in the RSE Directory 2003 (Session 2002-3) but some former Fellows who left the Society by resignation or were removed from the roll are still living. HISTORY OF THE PROJECT Information on the Fellowship has been kept by the Society in many ways – unpublished sources include Council and Committee Minutes, Card Indices, and correspondence; published sources such as Transactions, Proceedings, Year Books, Billets, Candidates Lists, etc. All have been examined by the compilers, who have found the Minutes, particularly Committee Minutes, to be of variable quality, and it is to be regretted that the Society’s holdings of published billets and candidates lists are incomplete. The late Professor Neil Campbell prepared from these sources a loose-leaf list of some 1500 Ordinary Fellows elected during the Society’s first hundred years. He listed name and forenames, title where applicable and national honours, profession or discipline, position held, some information on membership of the other societies, dates of birth, election to the Society and death or resignation from the Society and reference to a printed biography. -
The Worshipful Company of Clockmakers Past Masters Since 1631
The Worshipful Company of Clockmakers Past Masters since 1631 1631 David Ramsey (named in the Charter) 1700 Charles Gretton 1800 Matthew Dutton 1632 David Ramsey (sworn 22nd October) 1701 William Speakman 1801 William Plumley 1633 David Ramsey, represented by his Deputy, Henry Archer 1702 Joseph Windmills 1802 Edward Gibson 1634 Sampson Shelton 1703 Thomas Tompion 1803 Timothy Chisman 1635 John Willow 1704 Robert Webster 1804 William Pearce 1636 Elias Allen 1705 Benjamin Graves 1805 William Robins 1638 John Smith 1706 John Finch 1806 Francis S Perigal Jnr 1639 Sampson Shelton 1707 John Pepys 1807 Samuel Taylor 1640 John Charleton 1708 Daniel Quare 1808 Thomas Dolley 1641 John Harris 1709 George Etherington 1809 William Robson 1642 Richard Masterson 1710 Thomas Taylor 1810 Paul Philip Barraud 1643 John Harris 1711 Thomas Gibbs 1811 Paul Philip Barraud 1644 John Harris 1712 John Shaw 1812 Harry Potter (died) 1645 Edward East 1713 Sir George Mettins (Lord Mayor 1724–1725) 1813 Isaac Rogers 1646 Simon Hackett 1714 John Barrow 1814 William Robins 1647 Simon Hackett 1715 Thomas Feilder 1815 John Thwaites 1648 Robert Grinkin 1716 William Jaques 1816 William Robson 1649 Robert Grinkin 1717 Nathaniel Chamberlain 1817 John Roger Arnold 1650 Simon Bartram 1718 Thomas Windmills 1818 William Robson 1651 Simon Bartram 1719 Edward Crouch 1819 John Thwaites 1652 Edward East 1720 James Markwick 1820 John Thwaites 1653 John Nicasius 1721 Martin Jackson 1821 Benjamin Lewis Vulliamy 1654 Robert Grinkin 1722 George Graham 1822 John Jackson Jnr 1655 John Nicasius -
SXP 1062, a Young Be X-Ray Binary Pulsar with Long Spin Period⋆
A&A 537, L1 (2012) Astronomy DOI: 10.1051/0004-6361/201118369 & c ESO 2012 Astrophysics Letter to the Editor SXP 1062, a young Be X-ray binary pulsar with long spin period Implications for the neutron star birth spin F. Haberl1, R. Sturm1, M. D. Filipovic´2,W.Pietsch1, and E. J. Crawford2 1 Max-Planck-Institut für extraterrestrische Physik, Giessenbachstraße, 85748 Garching, Germany e-mail: [email protected] 2 University of Western Sydney, Locked Bag 1797, Penrith South DC, NSW1797, Australia Received 31 October 2011 / Accepted 1 December 2011 ABSTRACT Context. The Small Magellanic Cloud (SMC) is ideally suited to investigating the recent star formation history from X-ray source population studies. It harbours a large number of Be/X-ray binaries (Be stars with an accreting neutron star as companion), and the supernova remnants can be easily resolved with imaging X-ray instruments. Aims. We search for new supernova remnants in the SMC and in particular for composite remnants with a central X-ray source. Methods. We study the morphology of newly found candidate supernova remnants using radio, optical and X-ray images and inves- tigate their X-ray spectra. Results. Here we report on the discovery of the new supernova remnant around the recently discovered Be/X-ray binary pulsar CXO J012745.97−733256.5 = SXP 1062 in radio and X-ray images. The Be/X-ray binary system is found near the centre of the supernova remnant, which is located at the outer edge of the eastern wing of the SMC. The remnant is oxygen-rich, indicating that it developed from a type Ib event. -
Volume 36 March 2007 Number 3 from the Director
The Official Publication of the Amateur Astronomers Association of Princeton Director Treasurer Program Chairman Rex Parker Brian VanLiew Ken Kremer Assistant Director Secretary Editors John Miller Ludy D’Angelo Bryan Hubbard and Ira Polans Volume 36 March 2007 Number 3 From the Director presentation on March 30, he will share some of this experience through photos and video, including his most recent expedition to Libya AAAP Meeting March 13 (8:00 Peyton Hall). Our astronomical in 2006. Information about future solar eclipses visible from Princeton excursion heads next to an exciting new area with a novel will be distributed at this event, at which the public is also welcome presentation on Plasma Propulsion and the Exploration of (bring your kids too!). For more information, please go to the AAAP Space, by Dr. Edgar Choueiri, Director of Princeton's Electric website or contact Ken Kremer. Propulsion and Plasma Dynamics Lab (EPPDyL). Dr Choueiri is Associate Professor in the Mechanical and Aerospace Observing events coming up. The Observatory Committee and other Engineering (MAE) Dept at Princeton, and also Assoc. Faculty in members have been doing a great job organizing and getting the Astrophysics. With his deep background in plasma and space telescope/mount upgrade completed for the next observing season. At physics and applied mathematics, Dr Choueiri is a leading expert the recent Board meeting Feb 1, we decided to improve public outreach and proponent of advances in propulsion science and technology. (and member access) at the Observatory by scheduling every Friday In his talk he will describe from firsthand knowledge what this night in April-October as public observing nights. -
Download This Article (Pdf)
244 Trimble, JAAVSO Volume 43, 2015 As International as They Would Let Us Be Virginia Trimble Department of Physics and Astronomy, University of California, Irvine, CA 92697-4575; [email protected] Received July 15, 2015; accepted August 28, 2015 Abstract Astronomy has always crossed borders, continents, and oceans. AAVSO itself has roughly half its membership residing outside the USA. In this excessively long paper, I look briefly at ancient and medieval beginnings and more extensively at the 18th and 19th centuries, plunge into the tragedies associated with World War I, and then try to say something relatively cheerful about subsequent events. Most of the people mentioned here you will have heard of before (Eratosthenes, Copernicus, Kepler, Olbers, Lockyer, Eddington…), others, just as important, perhaps not (von Zach, Gould, Argelander, Freundlich…). Division into heroes and villains is neither necessary nor possible, though some of the stories are tragic. In the end, all one can really say about astronomers’ efforts to keep open channels of communication that others wanted to choke off is, “the best we can do is the best we can do.” 1. Introduction astronomy (though some of the practitioners were actually Christian and Jewish) coincided with the largest extents of Astronomy has always been among the most international of regions governed by caliphates and other Moslem empire-like sciences. Some of the reasons are obvious. You cannot observe structures. In addition, Arabic astronomy also drew on earlier the whole sky continuously from any one place. Attempts to Greek, Persian, and Indian writings. measure geocentric parallax and to observe solar eclipses have In contrast, the Europe of the 16th century, across which required going to the ends (or anyhow the middles) of the earth. -
Origin and Binary Evolution of Millisecond Pulsars
Origin and binary evolution of millisecond pulsars Francesca D’Antona and Marco Tailo Abstract We summarize the channels formation of neutron stars (NS) in single or binary evolution and the classic recycling scenario by which mass accretion by a donor companion accelerates old NS to millisecond pulsars (MSP). We consider the possible explanations and requirements for the high frequency of the MSP population in Globular Clusters. Basics of binary evolution are given, and the key concepts of systemic angular momentum losses are first discussed in the framework of the secular evolution of Cataclysmic Binaries. MSP binaries with compact companions represent end-points of previous evolution. In the class of systems characterized by short orbital period %orb and low companion mass we may instead be catching the recycling phase ‘in the act’. These systems are in fact either MSP, or low mass X–ray binaries (LMXB), some of which accreting X–ray MSP (AMXP), or even ‘transitional’ systems from the accreting to the radio MSP stage. The donor structure is affected by irradiation due to X–rays from the accreting NS, or by the high fraction of MSP rotational energy loss emitted in the W rays range of the energy spectrum. X– ray irradiation leads to cyclic LMXB stages, causing super–Eddington mass transfer rates during the first phases of the companion evolution, and, possibly coupled with the angular momentum carried away by the non–accreted matter, helps to explain ¤ the high positive %orb’s of some LMXB systems and account for the (apparently) different birthrates of LMXB and MSP. Irradiation by the MSP may be able to drive the donor to a stage in which either radio-ejection (in the redbacks) or mass loss due to the companion expansion, and ‘evaporation’ may govern the evolution to the black widow stage and to the final disruption of the companion. -
Space Telescope
rnal 5 Monty tarium of the Space Telescope ............ New ............................................... a 29 Gibbous Gazette ........................................... 32 Mobile News Network ............................................ 36 Planetechnica: Slip Rings .............................. 41 Reports from Committees ................................. 43 Secretary's Report ............................................. 47 President's Message ....................................... 54 jane's Corner ............................................................ Seeing Is Believing! In The U.S. & Canada contact Pearl Reilly: 1-800-726-8805 fax : 1-504-764-7665 email : [email protected] Aufflonzoo DlSlntJur", of ZetSS Plaflelilnums In The Umtoo Stares & Canada Carl Zeiss, Planelarium Division 0-07740 Jena ~SEILER +49-3641-642406, fax: -643023 email: [email protected] I N B TRLJIVlENT 170 E. Kirkham Ave ., St.louis. MO 63119 Planetarium Office: #28 Houmas Place, Destrehan, LA 70047 The Planetarian (ISN 0090-3213) is published quarterly by the International Dl"Ylai-,.,,,.',-,,,,,, Society. ©1998, International Planetarium Society, Inc., all rights reserved. Opinions exp1ressed e by authors are personal opinions and are not necessarily the opinions of the International etarium Society, its officers, or agents. Acceptance of advertisements, announcements, 1.27, No.4 material does not imply endorsement by the International Planetarium Society, its officers agents. The Editor welcomes items for consideration for publication. Please consult -
L\Srrronomy Al TD ASTRC)PIIYSICS I IBRARY
L\srrRONOMY Al TD ASTRC)PIIYSICS I IBRARY Series Editors: I. Appenzeller, Heidelberg, Gerrnany G. Börner, Garehing, Gerrnany M. Harwit, Washington, DC, USA R. Kippenhahn, Göttingen, Gerrnany J. Lequeux, Paris, France P. A. Strittmatter, Tueson, AZ, USA V. Trimble, College Park, MD, and Irvine, CA, USA ONLINE LlBRARY Physics and Astronomy http://www.springer.de/phys/ Springer-Verlag Berlin Heidelberg GmbH STRC) ():v1Y ANI) A I ROPf YSICS LfBRARY Series Editors: I. Appenzeller . G. Bömer . M. Harwit . R. Kippenhahn 1. Lequeux . P. A. Strittmatter . V. Trimble Stellar Physics (2 volumes) Galaxy Formation By M. S. Longair Volume I: Fundamental Concepts and Stellar Equilibrium Tools of Radio Astronomy 3rd Edition Volume 2: Stellar Evolution and Stability By K. Rohlfs and T. L. Wilson By G. S. Bisnovatyi-Kogan Tools of Radio Astronomy Theory of Orbits (2 volumes) Problems and Solutions Volume 1: Integrable Systems By T. L. Wilson and S. Hüttemeister and Non-perturbative Methods Atoms in Strong Magnetic Fields Volume 2: Perturbative Quantum Mechanical Treatment and Geometrical Methods and Applications in Astrophysics By D. Boccaletti and G. Pucacco and Quantum Chaos The Solar System 2nd Edition By H. Ruder, G. Wunner, H. Herold By T. Encrenaz and J.-P. Bibring and F. Geyer Physics of Planetary Rings The Stars Celestial Mechanics of Continuous Media By E. L. Schatzman and F. Praderie By A. M. Fridman, N. N. Gorkavyi Cosmic Ray Astrophysics The Physics and Dynamics By R. Schlickeiser ofPlanetary Nebulae By G.A. Gurzadyan Gravitational Lenses Astrophysical Concepts 2nd Edition By P. Schneider, J. Ehlers and E. E. Falco ByM.