PHYS 3160: Astrophysics - Fall 2008 1 PHYS 3160: Astrophysics
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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). -
2003 Astronomy Magazine Index
2003 astronomy magazine index Catchall (Martian crater), 11:30 observing Mars from, 7:32 hydrogen, 10:28 Subject index CCD (charge-coupled device) cameras, planets like, 6:48–53 Hydrus (constellation), 10:72–75 3:84–87, 5:84–87 seasons of, 3:72–73 A CCD techniques, 9:100–105 tilt of axis, 2:68, 5:72–73 I accidents, space-related, 7:42–47 Celestron C6-R (refractor), 11:84 EarthExplorer web site, 4:30 Achernar (star), 10:30 iceball, found beyond Pluto, 1:24 Celestron C8-N (reflector), 11:86 eclipses India, plans to visit Moon, 10:29 Advanced Camera for Surveys, 4:28 Celestron CGE-1100 (amateur telescope), in Australia (2003), 4:80–83 ALMA (Atacama Large Millimeter Array), infrared survey, 8:31 11:88 lunar integrating wavelengths, 4:24 3:36 Celestron NexStar 8 GPS (amateur telescope), of 2003, 5:18 Amalthea (Jupiter’s moon), 4:28 interferometry 1:84–87 of May 15, 2003, 5:60, 80–83, 88–89 techniques for, 7:48–53 Amateur Achievement Award, 9:32 Celestron NexStar 8i (amateur telescope), solar Andromeda Galaxy VLT interferometer, 2:32 11:89 of May 31, 2003, 5:80–83, 88–89 International Space Station, 3:31 picture of, 2:12–13 Centaurus A (NGC 5128) galaxy Edgar Wilson Award, 11:30 young stars in, 9:86–89 Internet, virtual observatories on, 9:80–85 1,000 Mira stars discovered in, 10:28 Egg Nebula, 8:36 Intes MK67 (amateur telescope), 11:89 Annefrank (asteroid), 2:32 picture of, 10:12–13 elliptical galaxies, 8:31 antineutrinos, 4:26 Io (Jupiter’s moon), 3:30 ripped apart satellite galaxy, 2:32 Eta Carinae (nebula), 5:29 ISAAC multi-mode instrument, 4:32 antisolar point, 10:18 Centaurus (constellation), 4:74–77 ETX-90EC (amateur telescope), 11:89 Antlia (constellation), 4:74–77 cepheid variable stars, 9:90–91 Europa (Jupiter’s moon), 12:30, 77 aphelion, 6:68–69 Challenger (space shuttle), 7:42–47 exoplanet magnetosphere, 11:28 J Apollo 1 (spacecraft), 7:42–47 J002E3 satellite, 1:30 Chamaeleon (constellation), 12:80–83 extrasolar planets. -
Binocular Certificate Handbook
Irish Federation of Astronomical Societies Binocular Certificate Handbook How to see 110 extraordinary celestial sights with an ordinary pair of binoculars © John Flannery, South Dublin Astronomical Society, August 2004 No ordinary binoculars! This photograph by the author is of the delightfully whimsical frontage of the Chiat/Day advertising agency building on Main Street, Venice, California. Binocular Certificate Handbook page 1 IFAS — www.irishastronomy.org Introduction HETHER NEW to the hobby or advanced am- Wateur astronomer you probably already own Binocular Certificate Handbook a pair of a binoculars, the ideal instrument to casu- ally explore the wonders of the Universe at any time. Name _____________________________ Address _____________________________ The handbook you hold in your hands is an intro- duction to the realm far beyond the Solar System — _____________________________ what amateur astronomers call the “deep sky”. This is the abode of galaxies, nebulae, and stars in many _____________________________ guises. It is here that we set sail from Earth and are Telephone _____________________________ transported across many light years of space to the wonderful and the exotic; dense glowing clouds of E-mail _____________________________ gas where new suns are being born, star-studded sec- tions of the Milky Way, and the ghostly light of far- Observing beginner/intermediate/advanced flung galaxies — all are within the grasp of an ordi- experience (please circle one of the above) nary pair of binoculars. Equipment __________________________________ True, the fixed magnification of (most) binocu- IFAS club __________________________________ lars will not allow you get the detail provided by telescopes but their wide field of view is perfect for NOTES: Details will be treated in strictest confidence. -
Biological Damage of Uv Radiation in Environments Of
BIOLOGICAL DAMAGE OF UV RADIATION IN ENVIRONMENTS OF F-TYPE STARS by SATOKO SATO Presented to the Faculty of the Graduate School of The University of Texas at Arlington in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY THE UNIVERSITY OF TEXAS AT ARLINGTON May 2014 Copyright c by Satoko Sato 2014 All Rights Reserved I dedicate this to my daughter Akari Y. Sato. Acknowledgements First of all, I would like to thank my supervising professor Dr. Manfred Cuntz. His advice on my research and academic life has always been invaluable. I would have given up the Ph.D. bound program without his encouragement and generous support as the supervising professor during a few difficult times in my life. I would like to thank Dr. Wei Chen, Dr. Yue Deng, Dr. Zdzislaw E. Musielak, and Dr. Sangwook Park for their interest in my research and for their time to serve in my committee. Next, I would like to acknowledge my research collaborators at University of Guanajuato, Cecilia M. Guerra Olvera, Dr. Dennis Jack, and Dr. Klaus-Peter Schr¨oder,for providing me the data of F-type evolutionary tracks and UV spectra. I would also like to express my deep gratitude to my parents, Hideki and Kumiko Yakushigawa, for their enormous support in many ways in my entire life, and to my sister, Tomoko Yakushigawa, for her constant encouragement to me. I am grateful to my husband, Makito Sato, and my daughter, Akari Y. Sato. Their presence always gives me strength. I am thankful to my parents-in-law, Hisao and Tsuguho Sato, and my grand-parents-in-law, Kanji and Ayako Momoi, for their financial support and prayers. -
9 Sagittarii: Uncovering an O-Type Spectroscopic Binary with an 8.6 Year Period , ,
A&A 542, A95 (2012) Astronomy DOI: 10.1051/0004-6361/201219254 & c ESO 2012 Astrophysics 9 Sagittarii: uncovering an O-type spectroscopic binary with an 8.6 year period,, G. Rauw1,,H.Sana2, M. Spano3, E. Gosset1,†,L.Mahy1, M. De Becker1, and P. Eenens4 1 Groupe d’Astrophysique des Hautes Énergies, Institut d’Astrophysique et de Géophysique, Université de Liège, Allée du 6 Août, Bât B5c, 4000 Liège, Belgium e-mail: [email protected] 2 Sterrenkundig Instituut “Anton Pannekoek”, Universiteit van Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands 3 Observatoire de Genève, Université de Genève, 51 Chemin des Maillettes, 1290 Sauverny, Switzerland 4 Departamento de Astronomia, Universidad de Guanajuato, Apartado 144, 36000 Guanajuato, GTO, Mexico Received 21 March 2012 / Accepted 10 May 2012 ABSTRACT Context. The O-type object 9 Sgr is a well-known synchrotron radio emitter. This feature is usually attributed to colliding-wind binary systems, but 9 Sgr was long considered a single star. Aims. We have conducted a long-term spectroscopic monitoring of this star to investigate its multiplicity and search for evidence for wind-wind interactions. Methods. Radial velocities are determined and analysed using various period search methods. Spectral disentangling is applied to separate the spectra of the components of the binary system. Results. We derive the first ever orbital solution of 9 Sgr. The system is found to consist of an O3.5 V((f+)) primary and an O5-5.5 V((f)) secondary moving around each other on a highly eccentric (e = 0.7), 8.6 year orbit. -
A Data Viewer for R
Paul Murrell A Data Viewer for R A Data Viewer for R Paul Murrell The University of Auckland July 30 2009 Paul Murrell A Data Viewer for R Overview Motivation: STATS 220 Problem statement: Students do not understand what they cannot see. What doesn’t work: View() A solution: The rdataviewer package and the tcltkViewer() function. What else?: Novel navigation interface, zooming, extensible for other data sources. Paul Murrell A Data Viewer for R STATS 220 Data Technologies HTML (and CSS), XML (and DTDs), SQL (and databases), and R (and regular expressions) Online text book that nobody reads Computer lab each week (worth 0.5%) + three Assignments 5 labs + one assignment on R Emphasis on creating and modifying data structures Attempt to use real data Paul Murrell A Data Viewer for R Example Lab Question Read the file lab10.txt into R as a character vector. You should end up with a symbol habitats that prints like this (this shows just the first 10 values; there are 192 values in total): > head(habitats, 10) [1] "upwd1201" "upwd0502" "upwd0702" [4] "upwd1002" "upwd1102" "upwd0203" [7] "upwd0503" "upwd0803" "upwd0104" [10] "upwd0704" Paul Murrell A Data Viewer for R The file lab10.txt upwd1201 upwd0502 upwd0702 upwd1002 upwd1102 upwd0203 upwd0503 upwd0803 upwd0104 upwd0704 upwd0804 upwd1204 upwd0805 upwd1005 upwd0106 dnwd1201 dnwd0502 dnwd0702 dnwd1002 dnwd1102 dnwd1202 dnwd0103 dnwd0203 dnwd0303 dnwd0403 dnwd0503 dnwd0803 dnwd0104 dnwd0704 dnwd0804 dnwd1204 dnwd0805 dnwd1005 dnwd0106 uppl0502 uppl0702 uppl1002 uppl1102 uppl0203 uppl0503 -
Line Profile Shapes in Optical H11 Regions
Assuming the dust composition did not change between geocentric distance of P/Crommelin remained constant within March 19 and March 31, and assuming the dust composition 2 % between these dates; in contrast, the visual magnitude to be homogeneous within the 30 arcsec diaphragm, we can changed rapidly, not only because ofthe heliocentric distance, compare our (J-H) and (H-K) values to the values derived from but also because of intrinsic cometary activity. Information the two other sets of observations. The agreement with upon the Mv curve is available from Marsden (1984) but a more Hanner and Knacke's data is reasonably good; in the case of complete analysis, involving more data, would be useful. Eaton and Zarnecki's measurement, there is some discre In conclusion, the preliminary results reported here show pancy for the (H-K) value. A possible explanation could be that the potential interest of near IR photometry for studying Eaton and Zarnecki's results, obtained in a sm aller diaphragm cometary dust, especially for future observations of Comet PI (6.2 arcsec) imply a contribution due to dirty ice grains; Halley. Extension towards higher wavelengths will be neces however, we would expect in this case the same behaviour in sary to obtain more constraints upon the nature and size ofthe Hanner and Knacke's results, which do not appear for (J-H); dust particles. A systematic study with different size dia moreover, the presence of a significant ice contribution in a phragms should allow a good determination of the dust sphere of about 3,500 km is not expected at a heliocentric density distribution. -
NCRAL Northern Lights Spring 2021
to continue serving as Northern Lights newsletter editor if the INSIDE THIS ISSUE OF Northern Lights new Regional Chair deems that desirable. The Region needs individuals willing to stand for election NCRAL Chair’s Message…..............................……………………1 to the following positions for our May election: Chair and Vice NCRAL Elections Online May 7-8, 2021…………………………….2 Chair. The terms of the current office holders – yours truly Basic NCRAL Officer Job Responsibilities…..…………….……….3 and Bill Davidson, expire on May 8th. Our present Secretary- NCRAL Financial Statement Winter 2021……..…………….……4 Treasurer, Roy Gustafson, is willing to stand for election to Pike River Starfest……………………..…………………….……..………4 complete the term to which he was appointed last spring after Call for 2021 NCRAL Nominations & Applications……….......5 NCRAL 2020 was postponed. Others may stand for election to NCRAL Seasonal Messier Marathon Awards…………….………7 this office too if they are desirous of completing the one-year Noteworthy!……………………………………………………………………7 unexpired term of the current office holder. Bill Davidson, our A Homebuilt Solar Wind Magnetometer………………..………..7 Regional Representative to the Astronomical League, Venus: Evening Star 2021 by Jeffrey L. Hunt………………..….10 continues in this position unless he should become Chair. Astronomical League 75th Anniversary Coming……..…….…18 This year’s elections will be conducted electronically with Future NCRAL Conventions…………………………………..…….….19 special electors. I sent out an email notice on February 22nd Seasonal Messier Mini Marathon Observing Program……19 about the election procedures to be followed in the event of Add Your Email Address to NCRAL Member Database…...20 not holding an annual business meeting. (That email is NCRAL Website………………………………………………………….….20 repeated starting on page 2 of this newsletter.) Procedures Regional Officer & Leader Contact Information………..……21 are stipulated by the Region’s Bylaws. -
A Test for the Theory of Colliding Winds: the Periastron Passage of 9 Sagittarii ? I
Astronomy & Astrophysics manuscript no. 9SgrCWBv4 c ESO 2018 March 26, 2018 A test for the theory of colliding winds: the periastron passage of 9 Sagittarii ? I. X-ray and optical spectroscopy G. Rauw1, R. Blomme2, Y. Naze´1;??, M. Spano3, L. Mahy1;???, E. Gosset1;y, D. Volpi2, H. van Winckel4, G. Raskin4, and C. Waelkens4 1 Groupe d’Astrophysique des Hautes Energies, Institut d’Astrophysique et de Geophysique,´ Universite´ de Liege,` Allee´ du 6 Aout,ˆ 19c, Batˆ B5c, 4000 Liege,` Belgium 2 Royal Observatory of Belgium, Ringlaan 3, 1180 Brussel, Belgium 3 Observatoire de Geneve,` Universite´ de Geneve,` 51 Chemin des Maillettes, 1290, Sauverny, Switzerland 4 Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Celestijnenlaan 200 D, 3001 Leuven, Belgium ABSTRACT Context. The long-period, highly eccentric O-star binary 9 Sgr, known for its non-thermal radio emission and its relatively bright X-ray emission, went through its periastron in 2013. Aims. Such an event can be used to observationally test the predictions of the theory of colliding stellar winds over a broad range of wavelengths. Methods. We have conducted a multi-wavelength monitoring campaign of 9 Sgr around the 2013 periastron. In this paper, we focus on X-ray observations and optical spectroscopy. Results. The optical spectra allow us to revisit the orbital solution of 9 Sgr and to refine its orbital period to 9.1 years. The X-ray flux is maximum at periastron over all energy bands, but with clear differences as a function of energy. The largest variations are observed at energies above 2 keV, whilst the spectrum in the soft band (0.5 – 1.0 keV) remains mostly unchanged indicating that it arises far from the collision region, in the inner winds of the individual components. -
Annual Report Publications 2012
Publications Publications in refereed journals based on ESO data (2012) The ESO Library maintains the ESO Telescope Bibliography (telbib) and is responsible for providing paper-based statistics. Access to the database for the years 1996 to present as well as information on basic publication statistics are available through the public interface of telbib (http://telbib.eso.org) and from the “Basic ESO Publication Statistics” document (http://www.eso.org/sci/libraries/edocs/ESO/ESOstats.pdf), respectively. In the list below, only those papers are included that are based on data from ESO facilities for which observing time is evaluated by the Observing Programmes Committee (OPC). Publications that use data from non-ESO telescopes or observations obtained during ‘private’ observing time are not listed here. Acharova, I.A., Mishurov, Y.N. & Kovtyukh, V.V. 2012, Alaghband-Zadeh, S., Chapman, S.C., Swinbank, A.M., Galactic restrictions on iron production by various Smail, I., Harrison, C.M., Alexander, D.M., Casey, types of supernovae, MNRAS, 420, 1590 C.M., Davé, R., Narayanan, D., Tamura, Y. & Umehata, Adami, C., Jouvel, S., Guennou, L., Le Brun, V., Durret, H. 2012, Integral field spectroscopy of 2.0< z<2.7 F., Clement, B., Clerc, N., Comerón, S., Ilbert, O., Lin, submillimetre galaxies: gas morphologies and Y., Russeil, D. & Seemann, U. 2012, Comparison of kinematics, MNRAS, 424, 2232 the properties of two fossil groups of galaxies with the Albrecht, S., Winn, J.N., Butler, R.P., Crane, J.D., normal group NGC 6034 based on multiband imaging Shectman, S.A., Thompson, I.B., Hirano, T. & and optical spectroscopy, A&A, 540, 105 Wittenmyer, R.A. -
The Flaring Activity of Pre-Main Sequence Stars in Very Young Open Clusters
http://lib.ulg.ac.be http://matheo.ulg.ac.be The flaring activity of pre-main sequence stars in very young open clusters Auteur : Nelissen, Marie Promoteur(s) : Rauw, Gregor Faculté : Faculté des Sciences Diplôme : Master en sciences spatiales, à finalité approfondie Année académique : 2016-2017 URI/URL : http://hdl.handle.net/2268.2/2504 Avertissement à l'attention des usagers : Tous les documents placés en accès ouvert sur le site le site MatheO sont protégés par le droit d'auteur. Conformément aux principes énoncés par la "Budapest Open Access Initiative"(BOAI, 2002), l'utilisateur du site peut lire, télécharger, copier, transmettre, imprimer, chercher ou faire un lien vers le texte intégral de ces documents, les disséquer pour les indexer, s'en servir de données pour un logiciel, ou s'en servir à toute autre fin légale (ou prévue par la réglementation relative au droit d'auteur). Toute utilisation du document à des fins commerciales est strictement interdite. Par ailleurs, l'utilisateur s'engage à respecter les droits moraux de l'auteur, principalement le droit à l'intégrité de l'oeuvre et le droit de paternité et ce dans toute utilisation que l'utilisateur entreprend. Ainsi, à titre d'exemple, lorsqu'il reproduira un document par extrait ou dans son intégralité, l'utilisateur citera de manière complète les sources telles que mentionnées ci-dessus. Toute utilisation non explicitement autorisée ci-avant (telle que par exemple, la modification du document ou son résumé) nécessite l'autorisation préalable et expresse des auteurs ou de -
Planet-Induced Emission Enhancements in HD 179949: Results from Mcdonald Observations
CSIRO PUBLISHING Publications of the Astronomical Society of Australia, 2012, 29, 141–149 http://dx.doi.org/10.1071/AS11074 Planet-Induced Emission Enhancements in HD 179949: Results from McDonald Observations L. GurdemirA, S. RedfieldB, and M. CuntzA,C ADepartment of Physics, University of Texas at Arlington, Arlington, TX 76019, USA BAstronomy Department, Van Vleck Observatory, Wesleyan University, Middletown, CT 06459, USA CCorresponding author. Email: [email protected] Abstract: We monitored the Ca II H and K lines of HD 179949, a notable star in the southern hemisphere, to observe and confirm previously identified planet induced emission (PIE) as an effect of star–planet interaction. We obtained high resolution spectra (R , 53 000) with a signal-to-noise ratio S/N \ 50 in the Ca II H and K cores during 10 nights of observation at the McDonald Observatory. Wide-band echelle spectra were taken using the 2.7-m telescope. Detailed statistical analysis of Ca II K revealed fluctuations in the Ca II K core attributable to planet induced chromospheric emission. This result is consistent with previous studies by Shkolnik et al. (2003). Additionally, we were able to confirm the reality and temporal evolution of the phase shift of the maximum of star–planet interaction previously found. However, no identifiable fluctuations were detected in the Ca II H core. The Al I l3944 A˚ line was also monitored to gauge if the expected activity enhancements are confined to the chromospheric layer. Our observations revealed some variability, which is apparently unassociated with planet-induced activity. Keywords: planet-star interactions — radiation mechanisms: nonthermal — stars: activity — stars: chromospheres — stars: individual (HD 179949) — stars: late-type Received 2011 December 17, accepted 2012 February 16, published online 2012 April 2 1 Introduction Canada–France–Hawaii Telescope (CFHT).