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The Observer's Handbook for 1929
The O bserver’s H andbook FOR 1929 PUBLISHED BY The Royal A stronomical Society of Canada E d ited by C. A. CHANT TWENTY-FIRST YEAR OF PUBLICATION TORONTO 198 College Street Printed for the Society 1929 CALENDAR The O bserver’s H andbook FOR 1929 PUBLISHED BY The Royal Astronomical Society of Canada TORONTO 198 C ollege Street Prin ted for the Society 1929 CONTENTS Preface ------- 3 Anniversaries and Festivals - 3 Symbols and Abbreviations - 4 Solar and Sidereal Time - 5 Ephemeris of the Sun - - - 6 Occultations of Fixed Stars by the Moon - 8 Times of Sunrise and Sunset - 9 Planets for the Year ------ 22 Eclipses in 1929 - - - - 26 The Sky and Astronomical Phenomena for each Month 28 Phenomena of Jupiter’s Satellites - 52 Meteors and Shooting Stars - - - 54 Elements of the Solar System - 55 Satellites of the Solar System - 56 Double Stars, with a short list - 57 Variable Stars, with a short list 59 Distances of the Stars - 61 The Brightest Stars, their magnitudes, types, proper motions, distances and radial velocities - 63 Astronomical Constants - 71 Index - - - - - - - 72 PREFACE It may be stated that four circular star-maps, 9 inches in diameter, roughly for the four seasons, may be obtained from the Director of University Extension, University of Toronto, for one cent each; also a set of 12 circular maps, 5 inches in diameter, with brief explanation, is supplied by Popular Astronomy, Northfield, Minn., for 15 cents. Besides these may be mentioned Young’s Uranography, containing four maps with R.A. and Decl. circles and excellent descriptions of the constellations, price 72 cents; Norton's Star Atlas and Telescopic Handbook (10s. -
Photometry Request-B Persei.Pdf
Will the radio source b Persei be eclipsed? R. T. Zavala1 & J. J. Sanborn2 December 14, 2012 The ellipsoidal variable star b Persei (HR1324, HD26961, V=4.6) consists of a non-eclipsing close binary (A-B) with a 1.5 day orbital period within a hierarchical triple system (AB-C) with a 701 day orbit (Hill et al. 1976). As with other close binary systems (e.g. β Per) b Per exhibits flares of non- thermal radio emission (Hjellming & Wade 1973). As noted by Hill et al. (1976) the evolutionary nature of the close binary in b Per is uncertain. It may already be a mass-transferring Algol binary, or it may be a precursor to the mass-transfer stage. The absence of eclipses in the close binary and b Per’s status as a single-lined spectroscopic binary limit our knowledge of this stellar radio source. Our observations using the Navy Precision Optical Interferometer (NPOI) resolved the AB-C components for the first time. The triple system orbit is nearly edge-on with an inclination of approximately 90 degrees (Fig. 1). This suggests the possibility of observing eclipses of the non- eclipsing (i ~ 40 degrees; Hill et al. 1976) close binary and the third star. The third star may eclipse both components of the close binary depending on the close binary orbital phase. Eclipses are important as they allow us to add lightcurve modeling to our arsenal of techniques for investigating the evolutionary state of the close binary components. The reality of our edge-on orbit for b Per C is supported by Hill et al. -
Stars and Their Spectra: an Introduction to the Spectral Sequence Second Edition James B
Cambridge University Press 978-0-521-89954-3 - Stars and Their Spectra: An Introduction to the Spectral Sequence Second Edition James B. Kaler Index More information Star index Stars are arranged by the Latin genitive of their constellation of residence, with other star names interspersed alphabetically. Within a constellation, Bayer Greek letters are given first, followed by Roman letters, Flamsteed numbers, variable stars arranged in traditional order (see Section 1.11), and then other names that take on genitive form. Stellar spectra are indicated by an asterisk. The best-known proper names have priority over their Greek-letter names. Spectra of the Sun and of nebulae are included as well. Abell 21 nucleus, see a Aurigae, see Capella Abell 78 nucleus, 327* ε Aurigae, 178, 186 Achernar, 9, 243, 264, 274 z Aurigae, 177, 186 Acrux, see Alpha Crucis Z Aurigae, 186, 269* Adhara, see Epsilon Canis Majoris AB Aurigae, 255 Albireo, 26 Alcor, 26, 177, 241, 243, 272* Barnard’s Star, 129–130, 131 Aldebaran, 9, 27, 80*, 163, 165 Betelgeuse, 2, 9, 16, 18, 20, 73, 74*, 79, Algol, 20, 26, 176–177, 271*, 333, 366 80*, 88, 104–105, 106*, 110*, 113, Altair, 9, 236, 241, 250 115, 118, 122, 187, 216, 264 a Andromedae, 273, 273* image of, 114 b Andromedae, 164 BDþ284211, 285* g Andromedae, 26 Bl 253* u Andromedae A, 218* a Boo¨tis, see Arcturus u Andromedae B, 109* g Boo¨tis, 243 Z Andromedae, 337 Z Boo¨tis, 185 Antares, 10, 73, 104–105, 113, 115, 118, l Boo¨tis, 254, 280, 314 122, 174* s Boo¨tis, 218* 53 Aquarii A, 195 53 Aquarii B, 195 T Camelopardalis, -
B Persei, a Fundamental Star Among the Radiostars
242 B PERSEI, A FUNDAMENTAL STAR AMONG THE RADIOSTARS Suzanne DEBARBAT Observatoire de Paris, DANOF/URA 1125 61 avenue de 1'Observatoire 75014 Paris ABSTRACT. Optical fluctuations of the radiostar (3 Persei are seen from 13 campaigns performed with the astrolabe located at the Paris Observatory. 1. INTRODUCTION Among the radiostars, fSPersei (Algol) - a fundamental star - was chosen by radioastronomers as a zero reference for right ascensions in radioastrometry. Since 1975 this fundamental star has been included in the observing programme performed by the "Astrolabe et systemes de re"fdrence" group in charge of the instrument at the Paris Observatory. The eight first campaigns published have been presented at the IAU Colloquium n° 100 (Belgrade 1987). The average of the mean square errors given were 0.004s in right ascension and 0.13" in declination, according to the FK4 and the constants in use at that time. 2. DETERMINATIONS AND ERRORS There are now thirteen campaigns available from 1975/76 to 1987/88 and they have been reduced in the FK5 system with the new fundamental constants according to the formulas established by Chollet (1984). Due to the fact that the group and the internal smoothing corrections (according to De"barbat et Guinot, 1970) are not yet available in the case of the FK5, the reduction have been performed for both FK4 and FK5. As an example of residuals, for the zenith distance, to which accuracy this quantity is obtainable when 12 transits (at east and at west) are observed, Table I gives the values for the 1983/1984 campaign (J 2000, FK4 and FK5). -
To Identify Irregularities in O-Cdiagrams with "Changes Of
VOL. 23, 1937 ASTRONOMY: STERNE AND CAMPBELL 115 CHANGES OF PERIOD IN VARIABLE STARS OF LONG PERIOD By T. E. STERNE AND L. CAMPBELL THE HARVARD COLLEGE OBSERVATORY Communicated December 23, 1936 One of us has investigated elsewhere' the mathematical theory of the accuracy of periods determined from dates of maximum, or minimum, or mth magnitude increasing or diminishing, of a variable star. The existence of cumulative errors2 in the periods of long-period variables was shown to provide a simple explanation for the major part of their observed irregu- larities of period, as revealed for instance by O-C diagrams,3 and plots of cycles against epoch number. The existence of cumulative errors was shown to be in itself sufficient to cause an erratic behavior in O-C diagrams, so that such diagrams did not by themselves furnish safe evidence for changes of true, or mean, period. Further, it was shown that a value of the mean period, obtained from observations extending over any finite interval of time, would be liable to errors of sampling, so that the mere existence of a scatter among' values of the mean period obtained from differing intervals of time was not in itself evidence for a changing true or mean period. Before the appearance of the previously mentioned investigations, it had been the common practice among workers in the field of variable stars to identify irregularities in O-C diagrams with "changes of period" in the stars. Thus, of the 566 variables with known long periods listed4 in the Katalog der Elemente des Lichtwechsels fur 1687 verdnderliche Sterne, sine terms were assigned to 85. -
The Winds of Cataclysmic Variables
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CERN Document Server 1997, in Cosmic Winds and the Heliosphere, ed. J. R. Jokipii, C. P. Sonett, & M. S. Giampapa (Tucson: Univ. of Arizona Press) THE WINDS OF CATACLYSMIC VARIABLES CHRISTOPHER W. MAUCHE Lawrence Livermore National Laboratory and JOHN C. RAYMOND Harvard-Smithsonian Center for Astrophysics We present an observational and theoretical review of the winds of cata- clysmic variables (CVs). Specifically, we consider the related problems of the geometry, ionization state, and mass-loss rate of the winds of CVs. We present evidence of wind variability and discuss the results of studies of eclipsing CVs. Finally, we consider the properties of accretion disk wind and magnetic wind models. Some of these models predict substantial angular momentum loss, which could affect both disk structure and binary evolution. I. Introduction Cataclysmic variables (CVs) are a large, diverse class of short- period semi-detached mass-exchanging binaries composed of a white dwarf, a late-type (G, K, or M) main-sequence secondary, and, typi- cally, an accretion disk. The various CV subtypes include novae, which are powered by the thermonuclear burning of material on the surface of the white dwarf, and dwarf novae and nova-like variables, which are powered by the accretion of material transferred from the secondary to the white dwarf. For recent reviews of CVs, refer to Cropper (1990), Livio (1994), and C´ordova (1995). Among the nova-like variables, there exists a class in which the magnetic field of the white dwarf is strong enough to influence the flow of material accreted by the white dwarf. -
Binary Studies with the Navy Precision Optical Interferometer
ISSN 1845–8319 BINARY STUDIES WITH THE NAVY PRECISION OPTICAL INTERFEROMETER C. A. HUMMEL1, R. T. ZAVALA2 and J. SANBORN3 1European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching, Germany 2U.S. Naval Observatory, Flagstaff Station, 10391 W. Naval Obs. Rd, Flagstaff, AZ 86001, USA 3Lowell Observatory and Northern Arizona University, Flagstaff, AZ 86001, USA Abstract. We present recent results from observations of binary and multiple systems made with the Navy Precision Optical Interferometer (NPOI) on ζ and σ Orionis A, ξ Tauri, HR 6493, and b Persei. We explain how the orbital modeling is performed and show that even triple systems can be constrained with the data. Key words: interferometry - binaries 1. Introduction Observations of binary stars are the bread-and-butter for optical interferom- eters. An easy exploit for the unrivaled angular resolution of long baseline interferometers, the measurement of the orbits of double-lined spectroscopic binaries affords the determination of fundamental parameters of stars as well as their distance from Earth. Interferometry thus extends the reach of using spectroscopic binaries to non-eclipsing pairs, as a special but unlikely geom- etry for seeing eclipses, which also allow the determination of high-precision stellar masses, is no longer required. After about a decade of developing the technique of long baseline optical interferometers, i.e. those combining independent telescopes observing in the visual or near-infrared bands with baselines in between them ranging from a few meters to over a hundred, three major facilities are now available for regular scientific observations, CHARA on Mt Wilson, California, NPOI on Anderson Mesa, Arizona, and VLTI on Cerro Paranal, Chile. -
The Observer's Handbook for 1921
T he O bserver's H andbook FOR 1921 PUBLISHED BY The Royal Astronomical Society of Canada E d it e d b y C. A. CHANT. THIRTEENTH YEAR OF PUBLICATION TORONTO 198 College Street Printed for the Society 1921 1921 CALENDAR 1921 T he O bserver's H andbook FOR 1921 PUBLISHED BY The Royal Astronomical Society of Canada TORONTO 198 College Street Printed for the Society 1921 CONTENTS Preface 3 Anniversaries and Festivals - - - - 3 Symbols and Abbreviations - - - - 4 Solar and Sidereal Time - - - - - 5 Ephemeris of the Sun ------ 6 Occultations of Fixed Stars by the Moon - - 8 Times of Sunrise and Sunset - - - - 8 Planets for the Year - - - - - 22 Eclipses for 1921 - - - - - 27 The Sky and Astronomical Phenomena for each Month - 28 Eclipses, etc., of Jupiter’s Satellites - - - 52 Meteors and Shooting Stars - - - - 54 Elements of the Solar System - - - 55 Satellites of the Solar System - - - - 56 Double Stars, with a short list - - - 57 Variable Stars, with a short list - - - 59 Distances of the Stars - - - - 61 Geographical Positions of Some Points in Canada - 63 Index --------64 PREFACE The H a n d b o o k for 1921 follows the same lines as that for 1920. The chief difference is in the omission of the extended table giving the distance, velocities, and other information regarding certain fixed stars; and the substitution of a fuller account of the planets for the year, with maps of their paths. As in the last issue, the brief descriptions of the constellations and the star maps are not included, since fuller information is available in a better form and at a reasonable price in many publica tions, such as: Young’s Uranography (price 72c.), Upton’s Star Atlas ($3.00) and McKready’s Beginner's Star Book (about $3.50.) To those mentioned in the body of the book; to Mr. -
Meteor.Mcse.Hu
MCSE 2016/3 meteor.mcse.hu A Mars négy arca SZJA 1%! Az MCSE adószáma: 19009162-2-43 A Tharsis-régió három pajzsvulkánja és az Olympus Mons a Mars Express 2014. június 29-én készült felvételén (ESA / DLR / FU Berlin / Justin Cowart). TARTALOM Áttörés a fizikában......................... 3 GW150914: elõször hallottuk az Univerzum zenéjét....................... 4 A csillagászat ............................ 8 meteorA Magyar Csillagászati Egyesület lapja Journal of the Hungarian Astronomical Association Csillagászati hírek ........................ 10 H–1300 Budapest, Pf. 148., Hungary 1037 Budapest, Laborc u. 2/C. A távcsövek világa TELEFON/FAX: (1) 240-7708, +36-70-548-9124 Egy „klasszikus” naptávcsõ születése ........ 18 E-MAIL: [email protected], Honlap: meteor.mcse.hu HU ISSN 0133-249X Szabadszemes jelenségek Kiadó: Magyar Csillagászati Egyesület Gyöngyházfényû felhõk – történelmi észlelés! .. 22 FÔSZERKESZTÔ: Mizser Attila A hónap asztrofotója: hajnali együttállás ....... 27 SZERKESZTÔBIZOTTSÁG: Dr. Fûrész Gábor, Dr. Kiss László, Dr. Kereszturi Ákos, Dr. Kolláth Zoltán, Bolygók Mizser Attila, Dr. Sánta Gábor, Sárneczky Krisztián, Mars-oppozíció 2014 .................... 28 Dr. Szabados László és Dr. Szalai Tamás SZÍNES ELÕKÉSZÍTÉS: KÁRMÁN STÚDIÓ Nap FELELÔS KIADÓ: AZ MCSE ELNÖKE Téli változékony Napok .................38 A Meteor elôfizetési díja 2016-ra: (nem tagok számára) 7200 Ft Hold Egy szám ára: 600 Ft Januári Hold .........................42 Az egyesületi tagság formái (2016) • rendes tagsági díj (jogi személyek számára is) Meteorok -
Appendix 1: Telescope Limiting-Magnitude and Resolution
Appendix 1: Telescope Limiting-Magnitude and Resolution Listed below are limiting-magnitudes and resolution values for a variety of common-sized ( SIZE in inches) backyard telescopes in use today, ranging from 2- to 14-in. in aperture. (The 2.4-in. entry is the ubiquitous 60 mm refractor, of which there are perhaps more than any other telescope in the world!) Values for the minimum visual magnitude ( MAG .) listed here are for single stars and are only very approximate, since experienced keen-eyed observers may see as much as a full magnitude fainter under excellent sky conditions. Companions to visual double stars—especially those in close proximity to a bright primary—are typically much more dif fi cult to see than is a star of the same magnitude placed alone in the eye- piece fi eld. Among the many variables involved are light pollution, sky conditions, optical quality, mirror and lens coatings, eyepiece design, obstructed or unob- structed optical system, color (spectral type) of the star, and even the age of the observer. Only a few representative limiting magnitudes are given here (in incre- ments of increasing aperture), as an indication of what an observer might typically expect to see in various sized telescopes. Three different values in arc-seconds are listed for resolution, which are for two stars of equal brightness and of about the sixth magnitude. These fi gures differ signi fi cantly for brighter, fainter and, espe- cially, unequal pairs. DAWES is the value based on Dawes’ Limit ( R = 4.56/A), RAYLEIGH on the Rayleigh Criterion ( R = 5.5/D), and MARKOWITZ on Markowitz’s Limit ( R = 6.0/D). -
The Identification of Hydrogen-Deficient Cataclysmic
The Identification of Hydrogen-Deficient Cataclysmic Variable Donor Stars1;2 Thomas E. Harrison Department of Astronomy, New Mexico State University, Box 30001, MSC 4500, Las Cruces, NM 88003-8001 Received ; accepted arXiv:1806.04612v1 [astro-ph.SR] 12 Jun 2018 { 2 { ABSTRACT We have used ATLAS12 to generate hydrogen-deficient stellar atmospheres to allow us to construct synthetic spectra to explore the possibility that the donor stars in some cataclysmic variables (CVs) are hydrogen deficient. We find that four systems, AE Aqr, DX And, EY Cyg, and QZ Ser have significant hydrogen deficits. We confirm that carbon and magnesium deficits, and sodium enhancements, are common among CV donor stars. The three Z Cam systems we observed are found to have solar metallicities and no abundance anomalies. Two of these objects, Z Cam and AH Her, have M-type donor stars; much cooler than expected given their long orbital periods. By using the combination of equivalent width measurements and light curve modeling, we have developed the ability to account for contamination of the donor star spectra by other luminosity sources in the binary. This enables more realistic assessments of secondary star metallicities. We find that the use of equivalent width measurements should allow for robust metallicities and abundance anomalies to be determined for CVs with M-type donor stars. Key words: stars | infrared: stars | stars: novae, cataclysmic variables | stars: abundances | stars: individual (DX And, RX And, AE Aqr, Z Cam, SY Cnc, EM Cyg, EY Cyg, SS Cyg, V508 Dra, AH Her, RU Peg, GK Per, QZ Ser) 1Partially based on observations obtained with the Apache Point Observatory 3.5-meter telescope, which is owned and operated by the Astrophysical Research Consortium. -
Dwarf Nova-Type Cataclysmic Variable Stars Are Significant Radio Emitters
MNRAS 000,1{13 (2016) Preprint 14 November 2018 Compiled using MNRAS LATEX style file v3.0 Dwarf nova-type cataclysmic variable stars are significant radio emitters Deanne L. Coppejans,1? Elmar. G. K¨ording,1 James C.A. Miller-Jones,2 Michael P. Rupen,3 Gregory R. Sivakoff,4 Christian Knigge,5 Paul J. Groot,1 Patrick A. Woudt,6 Elizabeth O. Waagen7 and Matthew Templeton 1Department of Astrophysics/IMAPP, Radboud University, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands 2International Centre for Radio Astronomy Research, Curtin University, GPO Box U1987, Perth, WA 6845, Australia 3National Research Council of Canada, Herzberg Astronomy and Astrophysics, Dominion Radio Astrophysical Observatory, P.O. Box 248, Penticton, BC V2A 6J9, Canada 4Department of Physics, University of Alberta, CCIS 4-183, Edmonton, Alberta T6G 2E1, Canada 5School of Physics and Astronomy, Southampton University, Highfield, Southampton SO17 1BJ, UK 6Department of Astronomy, University of Cape Town, Private Bag X3, 7701 Rondebosch, South Africa 7American Association of Variable Star Observers, 49 Bay State Road, Cambridge, MA 02138, USA Accepted XXX. Received YYY; in original form ZZZ ABSTRACT We present 8{12 GHz radio light curves of five dwarf nova (DN) type Cataclysmic Variable stars (CVs) in outburst (RX And, U Gem and Z Cam), or superoutburst (SU UMa and YZ Cnc), increasing the number of radio-detected DN by a factor of two. The observed radio emission was variable on time-scales of minutes to days, and we argue that it is likely to be synchrotron emission. This sample shows no correlation between the radio luminosity and optical luminosity, orbital period, CV class, or outburst type; however higher-cadence observations are necessary to test this, as the measured luminosity is dependent on the timing of the observations in these variable objects.