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Limits from the Hubble Space Telescope on a Point Source in SN 1987A
Limits from the Hubble Space Telescope on a Point Source in SN 1987A The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Graves, Genevieve J. M., Peter M. Challis, Roger A. Chevalier, Arlin Crotts, Alexei V. Filippenko, Claes Fransson, Peter Garnavich, et al. 2005. “Limits from the Hubble Space Telescopeon a Point Source in SN 1987A.” The Astrophysical Journal 629 (2): 944–59. https:// doi.org/10.1086/431422. Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:41399924 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Other Posted Material, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#LAA The Astrophysical Journal, 629:944–959, 2005 August 20 # 2005. The American Astronomical Society. All rights reserved. Printed in U.S.A. LIMITS FROM THE HUBBLE SPACE TELESCOPE ON A POINT SOURCE IN SN 1987A Genevieve J. M. Graves,1, 2 Peter M. Challis,2 Roger A. Chevalier,3 Arlin Crotts,4 Alexei V. Filippenko,5 Claes Fransson,6 Peter Garnavich,7 Robert P. Kirshner,2 Weidong Li,5 Peter Lundqvist,6 Richard McCray,8 Nino Panagia,9 Mark M. Phillips,10 Chun J. S. Pun,11,12 Brian P. Schmidt,13 George Sonneborn,11 Nicholas B. Suntzeff,14 Lifan Wang,15 and J. Craig Wheeler16 Received 2005 January 27; accepted 2005 April 26 ABSTRACT We observed supernova 1987A (SN 1987A) with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST ) in 1999 September and again with the Advanced Camera for Surveys (ACS) on the HST in 2003 November. -
Wolf-Rayet Stars in the Small Magellanic Cloud II
A&A 591, A22 (2016) DOI: 10.1051/0004-6361/201527916 Astronomy c ESO 2016 & Astrophysics Wolf-Rayet stars in the Small Magellanic Cloud II. Analysis of the binaries T. Shenar1, R. Hainich1, H. Todt1, A. Sander1, W.-R. Hamann1, A. F. J. Moffat2, J. J. Eldridge3, H. Pablo2, L. M. Oskinova1, and N. D. Richardson4 1 Institut für Physik und Astronomie, Universität Potsdam, Karl-Liebknecht-Str. 24/25, 14476 Potsdam, Germany e-mail: [email protected] 2 Département de physique and Centre de Recherche en Astrophysique du Québec (CRAQ), Université de Montréal, CP 6128, Succ. Centre-Ville, Montréal, Québec, H3C 3J7, Canada 3 Department of Physics, University of Auckland, Private Bag, 92019 Auckland, New Zealand 4 Ritter Observatory, Department of Physics and Astronomy, The University of Toledo, Toledo, OH 43606-3390, USA Received 8 December 2015 / Accepted 30 March 2016 ABSTRACT Context. Massive Wolf-Rayet (WR) stars are evolved massive stars (Mi & 20 M ) characterized by strong mass-loss. Hypothetically, they can form either as single stars or as mass donors in close binaries. About 40% of all known WR stars are confirmed binaries, raising the question as to the impact of binarity on the WR population. Studying WR binaries is crucial in this context, and furthermore enable one to reliably derive the elusive masses of their components, making them indispensable for the study of massive stars. Aims. By performing a spectral analysis of all multiple WR systems in the Small Magellanic Cloud (SMC), we obtain the full set of stellar parameters for each individual component. -
Copyrighted Material
Index Abulfeda crater chain (Moon), 97 Aphrodite Terra (Venus), 142, 143, 144, 145, 146 Acheron Fossae (Mars), 165 Apohele asteroids, 353–354 Achilles asteroids, 351 Apollinaris Patera (Mars), 168 achondrite meteorites, 360 Apollo asteroids, 346, 353, 354, 361, 371 Acidalia Planitia (Mars), 164 Apollo program, 86, 96, 97, 101, 102, 108–109, 110, 361 Adams, John Couch, 298 Apollo 8, 96 Adonis, 371 Apollo 11, 94, 110 Adrastea, 238, 241 Apollo 12, 96, 110 Aegaeon, 263 Apollo 14, 93, 110 Africa, 63, 73, 143 Apollo 15, 100, 103, 104, 110 Akatsuki spacecraft (see Venus Climate Orbiter) Apollo 16, 59, 96, 102, 103, 110 Akna Montes (Venus), 142 Apollo 17, 95, 99, 100, 102, 103, 110 Alabama, 62 Apollodorus crater (Mercury), 127 Alba Patera (Mars), 167 Apollo Lunar Surface Experiments Package (ALSEP), 110 Aldrin, Edwin (Buzz), 94 Apophis, 354, 355 Alexandria, 69 Appalachian mountains (Earth), 74, 270 Alfvén, Hannes, 35 Aqua, 56 Alfvén waves, 35–36, 43, 49 Arabia Terra (Mars), 177, 191, 200 Algeria, 358 arachnoids (see Venus) ALH 84001, 201, 204–205 Archimedes crater (Moon), 93, 106 Allan Hills, 109, 201 Arctic, 62, 67, 84, 186, 229 Allende meteorite, 359, 360 Arden Corona (Miranda), 291 Allen Telescope Array, 409 Arecibo Observatory, 114, 144, 341, 379, 380, 408, 409 Alpha Regio (Venus), 144, 148, 149 Ares Vallis (Mars), 179, 180, 199 Alphonsus crater (Moon), 99, 102 Argentina, 408 Alps (Moon), 93 Argyre Basin (Mars), 161, 162, 163, 166, 186 Amalthea, 236–237, 238, 239, 241 Ariadaeus Rille (Moon), 100, 102 Amazonis Planitia (Mars), 161 COPYRIGHTED -
25 June 2002 2. Country
DISCLAIMER : Translated from the original Spanish for the Ramsar Bureau, and provided to Wetlands International for use in the Ramsar Database. Translation not checked against original by Ramsar Bureau. Information Sheet on Ramsar Wetlands 1. Date this sheet was completed/updated: 25 June 2002 2. Country: Bolivia 3. Name of wetland: Lakes Poopó and Uru Uru 4. Geographical coordinates: Lake Poopó 18º 21’ – 19° 10’ South latitude 60º 24’ – 60° 50’ West longitude Lake Uru Uru 18° 03’ South latitude 67° 04’ West longitude 5. Altitude: 3686 metres above sea level 6. Area: 967,607 hectares 7. Overview: The salinity, shallow water, biotic characteristics and the typical climatic conditions of the Puno at this altitude make this wetland a strategic place for the conservation of many species. It is one of the main bodies of water where the Chilean flamingo (Phoenicopterus chilensis) and the Andean flamingo (Phoenicopterus andinus) reproduce. It is an important habitat for ducks, shore birds and migratory birds. Two of the oldest ethnic groups in continental South America, the Uru Muratos and the Chipayas, live in this environment. 8. Wetland type: M, N, Q, R, Ss and Zg Types of wetlands by decreasing order of importance: Q, R, Ss, M, N, Zg 9. Ramsar criteria: 1, 2, 3, 4, 5, 6, 7 and 8 Criteria that best characterize the site: 5 10. Map of site included? Please tick yes -or- no 11. Name and address of the compiler of this form: Omar Rocha Olivio Wildlife Conservation Society - Programa Bolivia Casilla 4778 La Paz, Bolivia [email protected] [email protected] 1 [email protected] 12. -
JOHN R. THORSTENSEN Address
CURRICULUM VITAE: JOHN R. THORSTENSEN Address: Department of Physics and Astronomy Dartmouth College 6127 Wilder Laboratory Hanover, NH 03755-3528; (603)-646-2869 [email protected] Undergraduate Studies: Haverford College, B. A. 1974 Astronomy and Physics double major, High Honors in both. Graduate Studies: Ph. D., 1980, University of California, Berkeley Astronomy Department Dissertation : \Optical Studies of Faint Blue X-ray Stars" Graduate Advisor: Professor C. Stuart Bowyer Employment History: Department of Physics and Astronomy, Dartmouth College: { Professor, July 1991 { present { Associate Professor, July 1986 { July 1991 { Assistant Professor, September 1980 { June 1986 Research Assistant, Space Sciences Lab., U.C. Berkeley, 1975 { 1980. Summer Student, National Radio Astronomy Observatory, 1974. Summer Student, Bartol Research Foundation, 1973. Consultant, IBM Corporation, 1973. (STARMAP program). Honors and Awards: Phi Beta Kappa, 1974. National Science Foundation Graduate Fellow, 1974 { 1977. Dorothea Klumpke Roberts Award of the Berkeley Astronomy Dept., 1978. Professional Societies: American Astronomical Society Astronomical Society of the Pacific International Astronomical Union Lifetime Publication List * \Can Collapsed Stars Close the Universe?" Thorstensen, J. R., and Partridge, R. B. 1975, Ap. J., 200, 527. \Optical Identification of Nova Scuti 1975." Raff, M. I., and Thorstensen, J. 1975, P. A. S. P., 87, 593. \Photometry of Slow X-ray Pulsars II: The 13.9 Minute Period of X Persei." Margon, B., Thorstensen, J., Bowyer, S., Mason, K. O., White, N. E., Sanford, P. W., Parkes, G., Stone, R. P. S., and Bailey, J. 1977, Ap. J., 218, 504. \A Spectrophotometric Survey of the A 0535+26 Field." Margon, B., Thorstensen, J., Nelson, J., Chanan, G., and Bowyer, S. -
Luminous Blue Variables
Review Luminous Blue Variables Kerstin Weis 1* and Dominik J. Bomans 1,2,3 1 Astronomical Institute, Faculty for Physics and Astronomy, Ruhr University Bochum, 44801 Bochum, Germany 2 Department Plasmas with Complex Interactions, Ruhr University Bochum, 44801 Bochum, Germany 3 Ruhr Astroparticle and Plasma Physics (RAPP) Center, 44801 Bochum, Germany Received: 29 October 2019; Accepted: 18 February 2020; Published: 29 February 2020 Abstract: Luminous Blue Variables are massive evolved stars, here we introduce this outstanding class of objects. Described are the specific characteristics, the evolutionary state and what they are connected to other phases and types of massive stars. Our current knowledge of LBVs is limited by the fact that in comparison to other stellar classes and phases only a few “true” LBVs are known. This results from the lack of a unique, fast and always reliable identification scheme for LBVs. It literally takes time to get a true classification of a LBV. In addition the short duration of the LBV phase makes it even harder to catch and identify a star as LBV. We summarize here what is known so far, give an overview of the LBV population and the list of LBV host galaxies. LBV are clearly an important and still not fully understood phase in the live of (very) massive stars, especially due to the large and time variable mass loss during the LBV phase. We like to emphasize again the problem how to clearly identify LBV and that there are more than just one type of LBVs: The giant eruption LBVs or h Car analogs and the S Dor cycle LBVs. -
Naming the Extrasolar Planets
Naming the extrasolar planets W. Lyra Max Planck Institute for Astronomy, K¨onigstuhl 17, 69177, Heidelberg, Germany [email protected] Abstract and OGLE-TR-182 b, which does not help educators convey the message that these planets are quite similar to Jupiter. Extrasolar planets are not named and are referred to only In stark contrast, the sentence“planet Apollo is a gas giant by their assigned scientific designation. The reason given like Jupiter” is heavily - yet invisibly - coated with Coper- by the IAU to not name the planets is that it is consid- nicanism. ered impractical as planets are expected to be common. I One reason given by the IAU for not considering naming advance some reasons as to why this logic is flawed, and sug- the extrasolar planets is that it is a task deemed impractical. gest names for the 403 extrasolar planet candidates known One source is quoted as having said “if planets are found to as of Oct 2009. The names follow a scheme of association occur very frequently in the Universe, a system of individual with the constellation that the host star pertains to, and names for planets might well rapidly be found equally im- therefore are mostly drawn from Roman-Greek mythology. practicable as it is for stars, as planet discoveries progress.” Other mythologies may also be used given that a suitable 1. This leads to a second argument. It is indeed impractical association is established. to name all stars. But some stars are named nonetheless. In fact, all other classes of astronomical bodies are named. -
1 Information Sheet on Ramsar Wetlands Official Translation by Charles Akin Siteref
Information Sheet on Ramsar Wetlands Official translation by Charles Akin Siteref: 6CL002 1. Date this sheet was completed/updated: 29 November 1996 2. Country: CHILE 3. Name of wetland: Salar de Surire 4. Geographical coordinates: 18°46 - 18°55'S; 68°58 - 69°56'W 5. Altitude: an average of 4,200 metres 6. Area: 15,858 hectares (total protected area) 7. Overview: The Surire salt marsh is part of the High Andean altiplano steppe (Gajardo, 1994). This landform extends between 4,000 and 5,000 metres in altitude forming a large flat area dominated by isolated mountains and inflowing and outflowing river basins. The basic vegetation is determined primarily by relief and the presence of bodies of water. The salt marsh is surrounded by vegetative communities dominated by bofedales de la tundra altiplánica (Quintanilla, 1988). A large number of non-metallic minerals (calcium and boric salts) are found here. At one corner of the salt marsh, there is a stream that begins in a large artesian hot spring (Salas, 1975). The fauna associated with this environment is very important, and the area is one of the four most important places for the reproduction of flamingos in Chile (Ormazábal, 1988). 8. Wetland type: dry salt marsh and saline lakes with seasonal fluctuations 9. Ramsar criteria: 1b,2a,2b,2c,3b 10. Map of site included? Please tick yes -or- no 11. Name and address of the compiler of this form: Victor Valverde Soto, Jefe Sección Fauna Silvestre U.G. Nacional Património Silvestre Corporación Nacional Forestal Av. Bulnes 259, Of. 604, Santiago de Chile 12. -
Astrophysics with New Horizons: Making the Most of a Generational Opportunity
Draft version October 3, 2018 Typeset using LATEX twocolumn style in AASTeX62 Astrophysics with New Horizons: Making the Most of a Generational Opportunity Michael Zemcov,1, 2 Iair Arcavi,3, 4 Richard Arendt,5 Etienne Bachelet,6 Ranga Ram Chary,7 Asantha Cooray,8 Diana Dragomir,9 Richard Conn Henry,10 Carey Lisse,11 Shuji Matsuura,12, 13 Jayant Murthy,14 Chi Nguyen,1 Andrew R. Poppe,15 Rachel Street,6 and Michael Werner16 1Center for Detectors, School of Physics and Astronomy, Rochester Institute of Technology, Rochester, NY 14623, USA 2Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109, USA 3Einstein Fellow at the Department of Physics, University of California, Santa Barbara, CA 93106-9530, USA 4Las Cumbres Observatory, 6740 Cortona Drive, Suite 102, Goleta, CA 93117-5575, USA 5CRESST II/UMBC Observational Cosmology Laboratory, Code 665, Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771, USA 6Las Cumbres Observatory, 6740 Cortona Dr Ste 102, Goleta, CA 93117-5575, USA 7U. S. Planck Data Center, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA 8Department of Physics and Astronomy, University of California, Irvine, CA 92697, USA 9NASA Hubble Fellow, Massachusetts Institute of Technology, Cambridge, MA 02139, USA 10Henry A. Rowland Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, MD 21218, USA 11Planetary Exploration Group, Space Department, Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD -
Annual Report 2017
Koninklijke Sterrenwacht van België Observatoire royal de Belgique Royal Observatory of Belgium Jaarverslag 2017 Rapport Annuel 2017 Annual Report 2017 Cover illustration: Above: One billion star map of our galaxy created with the optical telescope of the satellite Gaia (Credit: ESA/Gaia/DPAC). Below: Three armillary spheres designed by Jérôme de Lalande in 1775. Left: the spherical sphere; in the centre: the geocentric model of our solar system (with the Earth in the centre); right: the heliocentric model of our solar system (with the Sun in the centre). Royal Observatory of Belgium - Annual Report 2017 2 De activiteiten beschreven in dit verslag werden ondersteund door Les activités décrites dans ce rapport ont été soutenues par The activities described in this report were supported by De POD Wetenschapsbeleid De Nationale Loterij Le SPP Politique Scientifique La Loterie Nationale The Belgian Science Policy The National Lottery Het Europees Ruimtevaartagentschap De Europese Gemeenschap L’Agence Spatiale Européenne La Communauté Européenne The European Space Agency The European Community Het Fonds voor Wetenschappelijk Onderzoek – Le Fonds de la Recherche Scientifique Vlaanderen Royal Observatory of Belgium - Annual Report 2017 3 Table of contents Preface .................................................................................................................................................... 6 Reference Systems and Planetology ...................................................................................................... -
The Wolf-Rayet + of Star Binary AB7: a Warmer in the Small Magellanic Cloud+)
The Wolf-Rayet + Of star binary AB7: A Warmer in the Small Magellanic Cloud+) Manfred W. Pakull1) & Luciana Bianchi2) 1) Observatoire de Besançon, 25044 Besançon Cedex, France 2) Osservatorio Astronomico di Turino, 10025 Pino Torinese, Italy Summary Strong nebular Hell λ4686 recombination radiation (λ4686/Ηβ = 0.2) has recently been detected in the bright HII region N76 in the Small Magellanic Cloud by Testor & Pakull (1989). The rather symmetric intensity distribution suggests a nebular morphology which consists of a thick outer shell comprising the He*"1* and H+ ionization fronts and a central region of warm, highly ionized gas which is surrounded by a hollow inner shell. The source of the high nebular ionization is identified with the peculiar Wolf-Rayet + Of star spectroscopic binary AB7. Optical and UV spectra (cf. Figure) show in addition to hydrogen and helium absorption lines and the NIII λλ4634-41 complex from the Of star, only broad He II and weak NVemission lines due to the Wolf-Rayet companion. The absence of other diagnostic features qualifies the evolved component as a rare, high-excitation WN star (WN2 or WN1). Subtracting from the optical spectrum of AB7 suitably scaled spectra of SMC Ο stars up to the point that the absorption lines disappeared, suggests that the WN 1 component contributes about 30 % to the total optical light. ' 4000 4500 5000 5500 °' üoö ' iioö t7Ö5 üoö" Wavelength (A) WAVELENGTH (AI Optical and IUE spectra of the 06 IIIf+ WN1 binary AB 7 From the nebular λ4686 flux and the optical brightness of the WN1 star a black body Zanstra temperature of about 80 000 Κ and a luminosity of 106 Lo are derived. -
197 6Apjs. . .30. .451H the Astrophysical Journal Supplement Series, 30:451-490, 1976 April © 1976. the American Astronomical S
.451H The Astrophysical Journal Supplement Series, 30:451-490, 1976 April .30. © 1976. The American Astronomical Society. All rights reserved. Printed in U.S.A. 6ApJS. 197 EVOLVED STARS IN OPEN CLUSTERS Gretchen L. H. Harris* David Dunlap Observatory, Richmond Hill, Ontario Received 1974 September 16; revised 1975 June 18 ABSTRACT Radial-velocity observations and MK classifications have been used to study evolved stars in 25 open clusters. Published data on stars in 72 additional clusters are rediscussed and com- bined with the observations friade in this investigation to yield positions in the Hertzsprung- Russell diagram for 559 evolved stars in 97 clusters. Ages for the parent clusters were estimated from the main-sequence turnoff points, earliest spectral types, and bluest stars in the clusters themselves. The evolved stars were sorted into six age groups ranging from 4 x 106 yr to 4 x 108 yr, and the composite H-R diagram for each age group was then used to study the evolutionary tracks for stars of various masses. The observational results were found to be in reasonably good agreement with recent theoretical computations. The composite color-magnitude diagrams were found to be strikingly different from those of the rich open clusters in the Magellanic Clouds. At a given age the red giants in the Small Magellanic Cloud and the Large Magellanic Cloud clusters are brighter and bluer than their galactic counterparts. It is suggested that these effects may be accounted for by differences in metal abundance. Subject headings: clusters: open — galaxies: Magellanic Clouds — radial velocities — stars : evolution — stars : late-type — stars : spectral classification 1.