COMMISSION 27 of the I.A.U. INFORMATION BULLETIN on VARIABLE STARS Nos. 0101-0200 1965 July

Total Page:16

File Type:pdf, Size:1020Kb

COMMISSION 27 of the I.A.U. INFORMATION BULLETIN on VARIABLE STARS Nos. 0101-0200 1965 July COMMISSION 27 OF THE I.A.U. INFORMATION BULLETIN ON VARIABLE STARS Nos. 0101-0200 1965 July - 1967 May EDITOR: L. Detre KONKOLY OBSERVATORY 1525 BUDAPEST, Box 67, HUNGARY CONTENTS 0101 THE PERIOD OF THE MAGNETIC VARIABLE HD 8441 R. Steinitz 14 July 1965 0102 RU MONOCEROTIS D.Ya. Martynov 22 July 1965 0103 ROSINO'S OBJECT F. Bertola 24 July 1965 0104 RR LYRAE VARIABLES IN M92 E.S. Kheylo 11 September 1965 0105 V828 CYGNI W. Wenzel 13 September 1965 0106 NEW VARIABLE STARS G. Romano 30 September 1965 0107 BRIGHT SOUTHERN BV-STARS W. Strohmeier, R. Knigge, H. Ott 7 October 1965 0108 THE PERIOD OF THE SPECTROSCOPIC BINARY AND MAGNETIC STAR HD 8441 P. Renson 18 October 1965 0109 SPECTRAL VARIATIONS OF THE WR STAR HD 50896 R. Barbon, F. Bertola, F. Ciatti, R. Margoni 20 October 1965 0110 SUPERNOVA IN ANONYMOUS GALAXY C. Hoffmeister OBJECT ROSINO-ZWICKY NEAR M88 W. Wenzel 25 October 1965 0111 MINIMA OF ECLIPSING VARIABLES L.J. Robinson 27 October 1965 0112 CURRENT ELEMENTS OF RZ CASSIOPEIAE L.J. Robinson 1 November 1965 0113 SUPERNOVA 2h20.m8 + 30d 50' 1855.0 C. Hoffmeister THE SUPERNOVA IN NGC 3631 K. Lochel 8 November 1965 0114 MINIMA OF ECLIPSING VARIABLES L.J. Robinson 11 November 1965 0115 BRIGHT SOUTHERN BV-STARS W. Strohmeier, R. Knigge, H. Ott 10 November 1965 0116 OBSERVATIONS OF AL Cam W. Quester, W. Braune 22 November 1965 0117 FAINT SOUTHERN BV-STARS R. Knigge 27 December 1965 0118 PHOTOMETRIC LIGHT-CURVES OF SOUTHERN BV-STARS E. Schoffel 27 December 1965 0119 MINIMA OF ECLIPSING VARIABLES L.J. Robinson 27 December 1965 0120 BRIGHT SOUTHERN BV-STARS W. Strohmeier, H. Fischer, H. Ott 14 February 1966 0121 BV 394 = BD +42d 3471 8.m9 H. Ott 14 February 1966 0122 ON THE VARIABILITY OF HD 234677 P.F. Chugainov 27 February 1966 0123 NOUVELLES ETOILES VARIABLES R. Weber 7 March 1966 0124 VELOCITY CURVE OF BV 312 TAURI R. Margoni, A. Mammano 15 March 1966 0125 RZ VULPECULAE L. Meinunger 16 March 1966 0126 NEW FLARE STAR S9537 Per C. Hoffmeister 17 March 1966 0127 NEW BRIGHT VARIABLE STAR M.S. Snowden 18 March 1966 0128 NOTE ON THE AMPLITUDE OF THE CEPHEID RU Cam W. Wamsteker 22 March 1966 0129 MINIMA OF ECLIPSING VARIABLES L.J. Robinson 28 March 1966 0130 EMISSION LINES IN THE FLARE STAR YZ CMi G. Chincarini, A. Mammano 5 April 1966 0131 NEW ELEMENTS FOR THE BINARY BV 267 FROM PHOTOELECTRIC AND SPECTROSCOPIC OBSERVATIONS R. Margoni, A. Mammano, R. Biolchini, C. Bartolini 19 April 1966 0132 NOTE ON THE CLASSIFICATION OF BC Eri W.S. Fitch 22 April 1966 0133 RT Ceti L.J. Robinson 9 May 1966 0134 SPECTRUM OF THE EARLY-TYPE FLARE STAR BD +13d 1048 A. Mammano 5 May 1966 0135 NOTE ON THE AMPLITUDE OF RU Cam J. Smak 16 May 1966 0136 A NEW BRIGHT SOUTHERN VARIABLE STAR R. Deurinck, R. Briers 21 May 1966 0137 TWO NEW SHORT PERIOD VARIABLES R.L. Millis 31 May 1966 0138 PHOTOELECTRIC OBSERVATIONS OF THE NEW DELTA SCUTI VARIABLE HD 107904 A.A. Wachmann 9 June 1966 0139 PHOTOELECTRIC OBSERVATIONS OF NOVA Her 1963 G. Chincarini, V.S. Howard 14 June 1966 0140 BRIGHT SOUTHERN BV-STARS W. Strohmeier, H. Fischer, H. Ott 27 June 1966 0141 LONG PERIOD VARIABLE STARS WITH LARGE INTRINSIC POLARIZATION K. Serkowski 30 June 1966 0142 PHOTOELECTRIC OBSERVATION OF HD 116994 Kwan-Yu Chen 6 July 1966 0143 LIGHT VARIABILITY OF 20 CANUM VENATICORUM W.H. Wehlau, S.C.N. Chen, G. Symonds 7 July 1966 0144 HD +54d 2193 (5.m8) H. Schneller HD 156545 = BV 418 W. Strohmeier BV 345 = V796 Cyg H. Busch, K. Haussler 44 i BOOTIS H. Schneller 9 July 1966 0145 NOTE ON V796 Cyg = S4782 = BV 345 W. Strohmeier Y CYGNI H. Schneller NOUVELLE ETOILE VARIABLE E. Schweitzer 22 July 1966 0146 THE SECONDARY PERIOD OF THE RRab STAR Z CANUM VENATICORUM S. Kanyo 22 July 1966 0147 THE ECLIPSE OF AZ Cas P. Tempesti 25 July 1966 0148 PHOTOELECTRIC MINIMA OF ECLIPSING VARIABLES C. Popovici 5 August 1966 0149 MIRA PRIOR TO FABRICIUS P. Brosche 6 August 1966 0150 OBSERVATIONS OF VARIABLE F-TYPE STARS WITH SHORT PERIODS I.J. Danziger, R.J. Dickens 8 August 1966 0151 DS CYGNI A. Koeckelenbergh 22 August 1966 0152 NOTE ON THE VARIABLE RU Cam N.S. Nikolov CYCLIC AMPLITUDE VARIATIONS OF RU Cam L. Detre 26 August 1966 0153 IMPROVED ELEMENTS FOR SEVEN RR LYRAE STARS L.J. Robinson 1 September 1966 0154 MINIMA OF ECLIPSING VARIABLES L.J. Robinson 1 September 1966 0155 NOUVELLES ETOILES VARIABLES R. Weber 22 September 1966 0156 POSSIBLE FLARE ACTIVITY IN A G-TYPE STAR A.D. Andrews 23 September 1966 0157 FURTHER FLARE ACTIVITY IN BUTLER'S STAR IN THE SMC A.D. Andrews, C.J. Butler, J.P. Eksteen 26 September 1966 0158 NEW SOUTHERN VARIABLES W. Strohmeier 27 September 1966 0159 THE CEPHEID BV 428 = 26 Cir W. Strohmeier 29 September 1966 0160 Ton S 120: A NEW VERY SHORT-PERIOD ECLIPSING BINARY W. Krzeminski 6 October 1966 0161 BV 677 AND BV 714, TWO CEPHEIDS W. Strohmeier 7 October 1966 0162 DETERMINATION OF THE MASS AND THE MODEL OF THE VARIABLES: RT AURIGAE, ETA AQUILAE, X CYGNI, MIRA CETI AND BM CASSIOPEIAE OF POP.I, AND RR LYRAE AND TWO TYPICAL VARIABLES OF POP. II A. Masani, A. Martini, M. Nelli, E. Albino DS CYGNI Ch. Bertaud DS CYGNI R. Weber 10 October 1966 0163 APSIDAL MOTION IN AG PERSEI J. Morley 14 October 1966 0164 BV 449 AND BV 600, TWO BRIGHT EB-STARS W. Strohmeier 29 October 1966 0165 3C 446 J.H. Hunter Jr., A.J. Wesselink 10 November 1966 0166 ELEMENTS FOR TWO SONNEBERG EA-VARIABLES W. Strohmeier 21 November 1966 0167 REPARTITION DANS LE PLAN GALACTIQUE DES ETOILES DU TYPE U GEMINORUM M. Petit 24 November 1966 0168 ELEMENTS FOR SONNEBERG EA-VARIABLES (II) W. Strohmeier 26 November 1966 0169 T PYXIDIS A. Jones 10 December 1966 0170 EU TAURI E.F. Guinan 15 December 1966 0171 ON 12 RR LYRAE STARS IN M3 E.S. Kheylo 27 December 1966 0172 NEW MICROVARIABLE HD 117555 P.F. Chugainov 29 December 1966 0173 REMARK CONCERNING THE AMPLITUDE OF RU Cam DURING 1965 H. Huth, W. Wenzel 29 December 1966 0174 CSV 4769 H. Busch, K. Haussler 30 December 1966 0175 NEW VARIABLE STAR IN EQUULEUS S. Catalano, M. Rodono 3 January 1967 0176 IMPROVED AND CURRENT ELEMENTS FOR 50 CEPHEIDS G.S. Tsarevsky 4 January 1967 0177 VZ TELESCOPII A. van Hoof, E. Mertens 18 January 1967 0178 BRIGHT SOUTHERN BV-STARS W. Strohmeier 20 January 1967 0179 REPARTITION GALACTIQUE DES CEPHEIDS TYPIQUES DE GRANDE PERIODE M. Petit 24 January 1967 0180 MINIMA OF ECLIPSING VARIABLES L.J. Robinson 25 January 1967 0181 ELEMENTS FOR SONNEBERG VARIABLES (III) W. Strohmeier 1 February 1967 0182 18-MIN. LIGHT-VARIATIONS OF HZ 29 J. Smak 6 February 1967 0183 NOUVELLES ETOILES VARIABLES R. Weber 7 February 1967 0184 ELEMENTS FOR SONNEBERG VARIABLES (IV) W. Strohmeier 15 February 1967 0185 NEW VARIABLE STARS G. Romano PHOTOELECTRIC OBSERVATIONS OF TX UMa E. Pohl 20 February 1967 0186 V439 OPHIUCHI, A CEPHEID WITH SECONDARY PERIOD E.B. Gusev 23 February 1967 0187 MINIMA OF ECLIPSING VARIABLES I. Todoran, I. Popa 27 February 1967 0188 ELEMENTS FOR BV 646 AND BV 752 W. Strohmeier 2 March 1967 0189 LES MAXIMA FAIBLES DES ETOILES DU TYPE U GEMINORUM M. Petit 15 March 1967 0190 THE PERIOD OF AB ANDROMEDAE W. Quester 28 March 1967 0191 ELEMENTS OF THREE BAMBERG VARIABLES W. Strohmeier 28 March 1967 0192 A HISTORICAL RECORD POSSIBLE RELATED TO THE RADIO SOURCE Cas A P. Brosche 30 March 1967 0193 A NEW ECLIPSING VARIABLE STAR IN LEO (CORRECTION IN No. 198) R. de Carlo, G. Sabatini 1 April 1967 0194 WR 131 H. Busch PHOTOELECTRIC MINIMA OF AB And E. Pohl 12 April 1967 0195 BRIGHT SOUTHERN BV-STARS W. Strohmeier 12 April 1967 0196 RECENT OBSERVATIONS OF THE SUPERNOVA IN NGC 1058 F. Bertola 18 April 1967 0197 REVISED EPHEMERIS FOR NOVA T AURIGAE G.S. Mumford 24 April 1967 0198 PHOTOELECTRIC MINIMA FOR SW Lac E. Pohl 24 April 1967 0199 ELEMENTS FOR SONNEBERG VARIABLES (V) W. Strohmeier 30 April 1967 0200 THE BEAT-PERIOD IN THETA OPHIUCHI R. Briers 17 May 1967 .
Recommended publications
  • Variable Stars Observer Bulletin
    Amateurs' Guide to Variable Stars September-October 2013 | Issue #2 Variable Stars Observer Bulletin ISSN 2309-5539 Twenty new W Ursae Majoris-type eclipsing binaries from the Catalina Sky Survey Details for 20 new WUMa systems are presented, along with a preliminary The FU Orionis phenomenon model of the FU Orionis stars are pre-main-sequence totally eclipsing eruptive variables which appear to be a system GSC stage in the development of T Tauri 03090-00153. stars. Image: FU Orionis. Credit: ESO NSVS 5860878 = Dauban V 171 Carbon in the sky: A new Mira variable in Cygnus a few remarkable carbon stars The list of the most interesting and bright carbon stars for northern observers is presented. Right: TT Cygni. A carbon star. Credit & Copyright: H.Olofsson (Stockholm Nova Observatory) et al. Delphini 2013 Nova has reached magnitude 4.3 visual The "Heavenly Owl" on August 16 observatory: seeing above the Black Sea waterfront VS-COMPAS Project: variable stars research and data mining. More at http://vs-compas.belastro.net Variable Stars Observer Bulletin Amateurs' Guide to Variable Stars September-October 2013 | Issue #2 C O N T E N T S 04 NSVS 5860878 = Dauban V 171: a new Mira variable in Cygnus by Ivan Adamin, Siarhey Hadon A new Mira variable in the constellation of Cygnus is presented. The variability of the NSVS 5860878 source was detected in January of 2012. Lately, the object was identified as the Dauban V171. A revision is submitted to the VSX. 06 Twenty new W Ursae Majoris-type eclipsing binaries Credit: Justin Ng from the Catalina Sky Survey by Stefan Hümmerich, Klaus Bernhard, Gregor Srdoc 16 Nova Delphini 2013: a naked-eye visible flare in A short overview of eclipsing binary northern skies stars and their traditional by Andrey Prokopovich classification scheme is given, which concentrates on W Ursae Majoris On August 14, 2013 a new bright star (WUMa)-type systems.
    [Show full text]
  • Highlights of Discoveries for $\Delta $ Scuti Variable Stars from the Kepler
    Highlights of Discoveries for δ Scuti Variable Stars from the Kepler Era Joyce Ann Guzik1,∗ 1Los Alamos National Laboratory, Los Alamos, NM 87545 USA Correspondence*: Joyce Ann Guzik [email protected] ABSTRACT The NASA Kepler and follow-on K2 mission (2009-2018) left a legacy of data and discoveries, finding thousands of exoplanets, and also obtaining high-precision long time-series data for hundreds of thousands of stars, including many types of pulsating variables. Here we highlight a few of the ongoing discoveries from Kepler data on δ Scuti pulsating variables, which are core hydrogen-burning stars of about twice the mass of the Sun. We discuss many unsolved problems surrounding the properties of the variability in these stars, and the progress enabled by Kepler data in using pulsations to infer their interior structure, a field of research known as asteroseismology. Keywords: Stars: δ Scuti, Stars: γ Doradus, NASA Kepler Mission, asteroseismology, stellar pulsation 1 INTRODUCTION The long time-series, high-cadence, high-precision photometric observations of the NASA Kepler (2009- 2013) [Borucki et al., 2010; Gilliland et al., 2010; Koch et al., 2010] and follow-on K2 (2014-2018) [Howell et al., 2014] missions have revolutionized the study of stellar variability. The amount and quality of data provided by Kepler is nearly overwhelming, and will motivate follow-on observations and generate new discoveries for decades to come. Here we review some highlights of discoveries for δ Scuti (abbreviated as δ Sct) variable stars from the Kepler mission. The δ Sct variables are pre-main-sequence, main-sequence (core hydrogen-burning), or post-main-sequence (undergoing core contraction after core hydrogen burning, and beginning shell hydrogen burning) stars with spectral types A through mid-F, and masses around 2 solar masses.
    [Show full text]
  • Variable Stars Observer Bulletin 15.000 – 30.000
    the appropriate amount of shots with the same comparison stars and their brightness in the range exposures. Making the Flat files is a little more the data frames are. Amateurs' Guide to Variable Stars September-October 2013 | Issue #2 complicated. Ideally, they are easy to get on evening or predawn twilight sky. You need to With a series of photometric observations, we can choose the exposure to get a ¼ - ½ of the value of build a light curve, find the period of a variable complete saturation of the pixel. For example, full star, other parameters, depending on the saturation for 16 bit camera is 65535. The value of variability type. a pixel in the Flat file should be in the range of Variable Stars Observer Bulletin 15.000 – 30.000. I use 20.000. There are lots of software to make the analysis of the photometric data. A good example is a ISSN 2309-5539 Another way of obtaining the Flat files is to use the software package created by Andrey Prokopovich so-called flat-box. I use a white screen which is and Ivan Adamin (the VS-COMPAS project core attached to the dome. Am bringing him a team). There are desktop and web versions Twenty new W Ursae Majoris-type eclipsing telescope and the illuminating light bulb. For more available. It is a powerful software that allows you binaries from the Catalina Sky Survey scattered light, the telescope tube can be covered to build the light curves, search for possible with a white cloth. Flat files must be taken periods, combine data from a number of separately for each filter.
    [Show full text]
  • 1. Introduction
    1. Introduction Three variable stars with short periods and high-amplitude, CY Aqr, BP Peg, and GP And, are selected for the study, and the characteristic of each variable star is analyzed from their light curves. These three variable stars are difference a little, CY Aqr is probability a binary system, BP Peg is a type of delta Scuti star with two stable periods (Rodriguez et al., 1992), and GP And is a simple delta Scuti star. 1.1 Delta Scuti stars Delta Scuti, the fourth bright star in Scutum at V magnitude, 4.71, stand out as the prototype of one of these. On the HR diagram or temperature-luminosity diagram, the kind of variable stars were located in intersects of main sequence with instability strip shown in Figure 1. Figure 1. Delta Scuti stars were in intersects of main sequence with instability strip. Delta Scuti stars is the group of the second most numerous of pulsators in the Galaxy, after the pulsating white dwarfs, and their spectrum belong to type A to early F. Most delta Scuti stars belong to Population I (Antonello, Broglia & Mantegazza, 1986), but a few variables show low metals and 6 high space velocities typical of Population II (Rodriguez E., Rolland A. & Lopez de coca P., 1990). The delta Scuti stars is divided into two types, variable stars with high-amplitude delta Scuti (HADS) and high-amplitude SX Phe (HASXP) (Breger, 1983;Andreasen, 1983;Frolov and Irkaev, 1984). Both of them have asymmetrical light curve in V with amplitudes > 0.25 magnitude and probably hydrogen-burning stars in the main sequence or post main sequence stage.
    [Show full text]
  • Variable Star Section Circular
    The British Astronomical Association Variable Star Section Circular No. 177 September 2018 Office: Burlington House, Piccadilly, London W1J 0DU Contents Observers Workshop – Variable Stars, Photometry and Spectroscopy 3 From the Director 4 CV&E News – Gary Poyner 6 AC Herculis – Shaun Albrighton 8 R CrB in 2018 – the longest fully substantiated fade – John Toone 10 KIC 9832227, a potential Luminous Red Nova in 2022 – David Boyd 11 KK Per, an irregular variable hiding a secret - Geoff Chaplin 13 Joint BAA/AAVSO meeting on Variable Stars – Andy Wilson 15 A Zooniverse project to classify periodic variable stars from SuperWASP - Andrew Norton 30 Eclipsing Binary News – Des Loughney 34 Autumn Eclipsing Binaries – Christopher Lloyd 36 Items on offer from Melvyn Taylor’s library – Alex Pratt 44 Section Publications 45 Contributing to the VSSC 45 Section Officers 46 Cover images Vend47 or ASASSN-V J195442.95+172212.6 2018 August 14.294, iTel 0.62m Planewave CDK @ f6.5 + FLI PL09--- CCD. 60 secs lum. Martin Mobberley Spectrum taken with a LISA spectroscope on Aug 16.875UT. C-11. Total exposure 1.1hr David Boyd Click on images to see in larger scale 2 Back to contents Observers' Workshop - Variable Stars, Photometry and Spectroscopy. Venue: Burlington House, Piccadilly, London, W1J 0DU (click to see map) Date: Saturday, 2018, September 29 - 10:00 to 17:30 For information about booking for this meeting, click here. A workshop to help you get the best from observing the stars, be it visually, with a CCD or DSLR or by using a spectroscope. The topics covered will include: • Visual observing with binoculars or a telescope • DSLR and CCD observing • What you can learn from spectroscopy And amongst those topics the types of star covered will include, CV and Eruptive Stars, Pulsating Stars and Eclipsing Binaries.
    [Show full text]
  • Pennsylvania Science Olympiad Southeast
    PENNSYLVANIA SCIENCE OLYMPIAD SOUTHEAST REGIONAL TOURNAMENT 2015 ASTRONOMY C DIVISION EXAM MARCH 4, 2015 SCHOOL:________________________________________ TEAM NUMBER:_________________ INSTRUCTIONS: 1. Turn in all exam materials at the end of this event. Missing exam materials will result in immediate disqualification of the team in question. There is an exam packet as well as a blank answer sheet. 2. You may separate the exam pages. You may write in the exam. 3. Only the answers provided on the answer page will be considered. Do not write outside the designated spaces for each answer. 4. Include school name and school code number at the bottom of the answer sheet. Indicate the names of the participants legibly at the bottom of the answer sheet. Be prepared to display your wristband to the supervisor when asked. 5. Each question is worth one point. Tiebreaker questions are indicated with a (T#) in which the number indicates the order of consultation in the event of a tie. Tiebreaker questions count toward the overall raw score, and are only used as tiebreakers when there is a tie. In such cases, (T1) will be examined first, then (T2), and so on until the tie is broken. There are 12 tiebreakers. 6. When the time is up, the time is up. Continuing to write after the time is up risks immediate disqualification. 7. In the BONUS box on the answer sheet, name the gentleman depicted on the cover for a bonus point. 8. As per the 2015 Division C Rules Manual, each team is permitted to bring “either two laptop computers OR two 3-ring binders of any size, or one binder and one laptop” and programmable calculators.
    [Show full text]
  • Determination of Pulsation Periods of Delta Scuti Variable Stars Using Ubvri Photometry
    DETERMINATION OF PULSATION PERIODS OF DELTA SCUTI VARIABLE STARS USING UBVRI PHOTOMETRY By G.R.D.S. Godagama (S/10/719) Supervised by Dr. T. P. Ranawaka (Department of physics, University of Peradeniya) Mr. S. Gunasakara and Mr. J. Adasuriya (Space Application Division of Arthur C. Clark Institute of Modern Technologies, Moratuwa) Department of physics, Faculty of science, University of Peradeniya-2015 DETERMINATION OF PULSATION PERIODS OF DELTA SCUTI VARIABLE STARS USING UBVRI PHOTOMETRY A PROJECT REPORT PRESENTED BY G.R.D.S. GODAGAMA In partial fulfilment of the requirement For the award of the degree of B.Sc. (physics special) Of the Faculty of Science, University of Peradeniya, Sri Lanka. 2014/2015 ii ACKNOWLEDGEMENT I hereby extent my sincere gratitude to my supervisors, Dr T.P. Ranawaka, Mr S. Gunasakara and Mr J. Adasuriya for their support throughout the course of this project. I am thankful for their aspiring guidance, invaluably constructive criticism and friendly advice during the project work. I am sincerely grateful to the Arthur C. Clark Institute of Modern Technologies, Srilanka for giving me the opportunity to carry out this research and facilitating me throughout the project. I extent my sincere thanks to Mr Uthpala Herath for his support and brotherly advices. I also express my warm thanks to my family for their constant support and facilitation in my academic life. I am thankful to everyone who sharing their truthful and illuminating views on a number of issues related to the project. G.R.D.S. Godagama At the Faculty of Science, University of Peradeniya, Srilanka.
    [Show full text]
  • P10263v2.0 Lab 6 Text
    Physics 10263 Lab #6: Citizen Science - Variable Star Zoo Introduction This lab is the another “Citizen Science” lab we will do together this semester as part of the zooniverse.org project family. This time, we will first learn a little background about variable stars, then we will be identifying different types of variable stars in our own Milky Way Galaxy. This work will help astronomers determine the luminosity, mass and age of these stars. With this information, astronomers can construct a more accurate three-dimensional map of the galaxy, learn more details about the process of stellar evolution, and reconstruct the history of star and cluster formation in the galaxy. Introduction to Variable Stars Use a browser to navigate to https://tinyurl.com/y7rnwxpf, and read through the introductory material, answering the questions below as you go. Q1. Explain what is the Main Sequence on an H-R diagram, and explain what all main sequence stars have in common (regarding their cores). !47 Q2. Explain what is a light curve for a star. Q3. What two properties of a star’s light curve determine which type of variable star it is? Q4. Name two differences between the properties of Cepheid variable stars and RR Lyrae variable stars. !48 Q5. Name two differences between Long Period Variables (like Mira) and Semiregular Variables (like Antares). Next, read through a more detailed discussion of Cepheid and RR Lyrae stars: https://www.aavso.org/vsots_rrlyr Q6. Briefly describe one reason why the “binary hypothesis” for the variation in RR Lyrae stars was proven to be incorrect by Shapley.
    [Show full text]
  • The COLOUR of CREATION Observing and Astrophotography Targets “At a Glance” Guide
    The COLOUR of CREATION observing and astrophotography targets “at a glance” guide. (Naked eye, binoculars, small and “monster” scopes) Dear fellow amateur astronomer. Please note - this is a work in progress – compiled from several sources - and undoubtedly WILL contain inaccuracies. It would therefor be HIGHLY appreciated if readers would be so kind as to forward ANY corrections and/ or additions (as the document is still obviously incomplete) to: [email protected]. The document will be updated/ revised/ expanded* on a regular basis, replacing the existing document on the ASSA Pretoria website, as well as on the website: coloursofcreation.co.za . This is by no means intended to be a complete nor an exhaustive listing, but rather an “at a glance guide” (2nd column), that will hopefully assist in choosing or eliminating certain objects in a specific constellation for further research, to determine suitability for observation or astrophotography. There is NO copy right - download at will. Warm regards. JohanM. *Edition 1: June 2016 (“Pre-Karoo Star Party version”). “To me, one of the wonders and lures of astronomy is observing a galaxy… realizing you are detecting ancient photons, emitted by billions of stars, reduced to a magnitude below naked eye detection…lying at a distance beyond comprehension...” ASSA 100. (Auke Slotegraaf). Messier objects. Apparent size: degrees, arc minutes, arc seconds. Interesting info. AKA’s. Emphasis, correction. Coordinates, location. Stars, star groups, etc. Variable stars. Double stars. (Only a small number included. “Colourful Ds. descriptions” taken from the book by Sissy Haas). Carbon star. C Asterisma. (Including many “Streicher” objects, taken from Asterism.
    [Show full text]
  • Delta Scuti Variable Stars with Kepler
    Studying Hybrid gamma Doradus/ delta Scuti Variable Stars with Kepler Joyce A. Guzik (for the Kepler Asteroseismic Science Consortium) Los Alamos National Laboratory 25th Annual New Mexico Astronomy Symposium Socorro, NM January 15, 2010 1/14/10 LA-UR-10-00139 1 http://arxiv.org/abs/1001.0747 1/14/10 2 The NASA Kepler Mission Launched March 6, 2009 Search for habitable planets High-precision CCD photometry to detect planetary transits Secondary mission to monitor variability of over 100,000 stars for asteroseismology http://kepler.nasa.gov 1/14/10 3 γ Dor and δ Sct hybrids are ideal candidates for asteroseismology Pulsate in many simultaneous radial and nonradial modes. Similarities with solar like stars, so can build on experience with the Sun Slightly more massive than Sun (1.4-1.6 Msun) Convective cores, shallower convective envelope Exhibit modes found in both types of variables that are sensitive to the structure of different regions of the stellar interior. Figure from J. Christensen-Dalsgaard 1/14/10 4 Properties of γ Doradus Variables Pulsating late A-F stars On or near main sequence Periods ~ 0.3 - 3 days Multiple photometric (a few mmag) and spectroscopic variables (up to 4 km s-1) Undergo gravity-mode pulsations of high radial order (n) and low- degree (l) More than 60 bona fide current members (Henry, Fekel, Henry 2007) (from Pollard 2009) 1/14/10 5 Properties of δ Scuti Variables Pulsating A-early F stars On or near main sequence Periods ~ 2 hours Observed in pressure-mode or mixed p- and g-mode pulsations of low-degree (l) Hundreds known (Rodriguez et al.
    [Show full text]
  • Title of the Paper
    Variable Star and Exoplanet Section of Czech Astronomical Society and Masaryk University Proceedings of the 50th Conference on Variable Stars Research Masaryk University (Department of Theoretical Physics and Astrophysics), Brno, Czech Republic 30th November - 2nd December 2018 Editor-in-chief Radek Kocián Participants of the conference OPEN EUROPEAN JOURNAL ON VARIABLE STARS March 2019 http://var.astro.cz/oejv ISSN 1801-5964 TABLE OF CONTENTS The Basic Informatics approach applied to the Modeling and Observations of the QS Virginis System ................ 4 V. BAHYL, M. GAJTANSKA, TINH PHAM VAN Variability of the Spin Periods of Intermediate Polars: Recent Results ................................................................... 8 V. BREUS, I.L. ANDRONOV, P. DUBOVSKY, K. PETRIK, S. ZOLA A new multi-periodic delta Scuti variable in the field of NS Cep .......................................................................... 10 V. DIENSTBIER, M. WOLF & M. SKARKA The peculiar outburst activity of the symbiotic binary AG Draconis ..................................................................... 15 R. GÁLIS, J. MERC, L. LEEDJÄRV, M. VRAŠŤÁK & S. KARPOV Activity of flare star GJ 3236 ................................................................................................................................. 21 J. KÁRA The activity of the symbiotic binary Z Andromedae and its latest outburst .......................................................... 23 J. MERC, R. GÁLIS, M. WOLF, L. LEEDJÄRV, F. TEYSSIER Improvement of Simplified
    [Show full text]
  • A Summary of the Different Classes of Stellar Pulsators
    A Summary of the Different Classes of Stellar Pulsators A summary of all the classes of pulsating stars and their main properties as described in Chapter 2 is given in the tables below. This list originated from a combination of observational discoveries, measured stellar properties, and theoretical developments. Observers who found a new type of pulsator either named it after the prototype or gave the class a name according to the ob- served characteristics of the oscillations. Several pulsators, or even groups of pulsators, were afterwards found to originate from the same physical mech- anism and were thus merged into one and the same class. We sort this out here in Tables A.1 and A.2 in order to avoid further confusion on pulsating star nomenclature. The effective temperature and luminosity indicated in Tables A.1 and A.2 should be taken as rough indications only of the borders of instability strips. Often the theory is not sufficiently refined to consider these boundaries as final. Moreover, there is overlap between various classes where so-called hy- brid pulsators, whose oscillations are excited in two different layers and/or by two different mechanisms, occur. Finally, new discoveries are being made frequently, which then drive new theoretical developments possibly leading to new instability regions. The results from the future observing facilities as described in Chapter 8 will surely lead to new classes and/or subclasses with lower amplitudes compared to what is presently achievable. In the tables below, F stands for fundamental radial mode, FO for first radial overtone and S for strange mode oscillations.
    [Show full text]