DOCSLIB.ORG

Die Farben Der Fixsterne

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Die Farben Der Fixsterne ASTRONOMISCHE NACHRICHTEN. N2 3657-58. Band 153. 9-10. ~~ ~~ Die Farben der Fixsterne. Von H. Osthf in C6ln. I. oo weiss I gelblicbweiss Obwohl ich mich schon seit a5 Jahren mit den Stern- 2 weissgelb (weiss und gelb zu gleicheo Theilen) farben beschiftige, liegen diesem Artikel Beobachtungen nur 3 hell- oder blassgelb zu Grunde, die ich in den Jahren mit einem 1885-1893 4 reingelb terrestrischen Fernrohr (t. R.) von 34 mm Objectivoffnung, 5 dunkelgelb a8 cm Brennweite, f. Vergrosserung und von 18 1893-1899 6 rothlichgelb (gelb (iberwiegt) mit einem Steioheil'schen Refractor (bezeichnet mit 4 Zoll.) von mm Objectivoffnung, cm Brennweite und 40f. 7 rothgelb (gelb und roth zu gleichen Theilen; orange) 108 162 8 gelblichroth (roth tiberwiegt) Vergr6sserung ausgeftihrt habe. 9 roth mit geringer Spur gelb 10 roth. 1. Der Beobachtungsraum war stets verdunkelt. Meinen Absichtlich habe ich die bisher iiblichen, vie1 zu un- Kopf sammt dem Ocularende des Fernrohrs verhtillte ich bestimmten Bezeichnungen schwefel-, strohgelb, feuer-, kupfer-, durch ein schwarzes Tuch. Die Beobachtungen wurden im blutroth und dergleichen vermieden. Dunkelo niedergeschrieben und die Farbe stets durch eine Der Endpunkt der Scala kano beliebig verlingert Ziffer ausgedrtickt. Nur in den dringendsten Fallen wurde werden, z. 9. durch wkhrend der Beobachtungszeit die Laterne geoffnet, urn die Sternkarte nachsehen zu konnen. Sonst bestimmte ich mir I oo hell unbekannte Sterne durch Beziehung auf bekannte. Nach I I mittel rein roth. Schluss der Beobachtungen, noch in der Nacht, spatestens 12 dunkel I am folgenden Morgen habe ich die Notizen durchgesehen und die Sterne identificirt. Vor Beginn eines jeden Beob- An den Anfang kann man setzen: achtungsabends nahm ich Einsicht in das Programm, kiim- - io glanzend merte mich aber nie urn die schon vorhandenen Beobachtungen. rein weiss. o matt Bei zu hellem Mondschein, unruhiger Luft und zu dunstigem Himmel habe ich nie Farben geschitzt. Jeden Stern habe ich solange fixirt, bis der Farbeneindruck un- Durch Jahre lange Anwenduog auf viele Sterne mit veranderlich feststand. Aus zahlreichen Abenden erhielt ich Tausenden von Schatzungen habe ich die Brauchbarkeit der Scala erprobt und gefunden, dass sie den VerhPltnissen am als mittlere Dauer eioer Farbenschatzung 2.2 1 Minuten. Die Zeit des Einstellens des Sterns und des Niederschreibens Fixsternhimmel wirklich entspricht, solange es sich um ge- der Beobachtung abgerechnet, bleiben fur das Fixiren selbst ntigend helle Sterne handelt. Geniigt aber die Helligkeit nicht mehr, so verwandelt sich weiss in grau, gelb in braun, 11/~-a Minuten, weil es sich nur um hellere Sterne handelte, bei denen der Sucher nicht angewandt zu werden brauchte. orange in rothbrauo. Auch rothbraun und broncefarben Die Sterne wurden scharf eingestellt. Stets ist mit voller treten auf. Das Gewimmel der kleinsten Sterne erglPnzt Objectivohung beobachtet; bei dem 4 Zoll. ist spater eine schliesslich eintonig grau. Thaukappe vorgesetzt worden. Was die erforderliche Anzahl Die Farben blau und grUn sind subjectiv. Sie ent- der Schitzungen betrifft, um die Farbe eines Sterns im Mittel stehen, wenn der Beobachter den Einfluss fremden Lichtes moglichst sicher zu erhalten, so halte ich nach erlangter - gleichzeitigen sowohl wie vorausgegangenen - nicht ver- Uebung 5- 10 fur ausreichend, die auf moglichst ebenso mieden hat. Zu diesem gehijren der Schimmer des stern- viele Abende zu vertheilen sind. besaten Himmels sowie der Metalltheile des Instruments, 3. ferner Mondschein, sowie tiberhaupt erhelltes Gesichtsfeld. Meine Farbenschatzuogen sind in der Scala von Schmidt Diese Bemerkungen finden jedoch keine Anwendung ausgedrlickt, deren Stufen ich folgendermaassen definirt habe : auf die wirklich blauen Begleiter farbiger Doppelsterne. II I 43 365 7 ’ 44 4. Tab. I. Haufigkeit der Farben der Sterne des Catalogs nordlich vom Aequator. 4 ~611.Refr. Scheinb. Gr. I/ I’ 1 2O Irn I - 3 I I I - 2 4 10 I 3 2 5- 3 - I4 16 -4 ‘3 I1 4 4 64 49 33 36 21 124 60 44 86 88 1 var. 2 I -6 Sa. 99 in o/o der Gesammtzahl 056 1 12.0 Unter der Einschrinkung, dass der weisslichste und Von weisslichen sind nur die hellsten sicher als solche zu der r6thlichste Stern ihren Rang immer nur fur ein be- erkennen, gewohnlich rnit blau gemischt. stimmtes Fernrohr behaupten, bezeichne ich als den geringst Durch diese Bestimmungen lasst sich der Farben- gefarbten der Sterne meines Catalogs, giiltig fiir den 4 Zoll., wechsel der Nova Cassiopeiae von 1572 aufklaren. (Vgl. Sirius pit 006, demnlchst Rigel = 0?9. Der farbigste ist Zollner, Photom. Unters. S. 248). Anfangs weiss (> Sirius), 19 Piscium = 808. Hierbei sind die Veranderlichen aus- ging die Farbe durch gelb (< a) zu roth tiber (zrn). Solch geschlossen worden. Zu diesen gehort p Cephei mit 8Co. ein Farbenwechsel findet nun nie bei der Lichtabnahme Unter den rnit blossem Auge sichtbaren Sternen bleibt dem- eines Sterns statt, einerlei aus welcher Ursache diese erfolgen nach Herschel’s Granatstern einer der farbigsten, wenngleich mag., Die Erscheinung deutet auf eine Katastrophe. Der diese Farbe selbst rnit blossem Auge nicht erkennbar ist. nun bei weiterer Lichtabnahrne eintretende bleifarbene Too (albedo sublivida) ist physiologischen Ursprungs und durch 5. Lichtschwache hervorgerufen, bei welcher die eigentliche Um die Farbenangaben aus der Zeit vor Erfindung Farbe unkenntlich wurde. des Fernrohrs controlliren zu konnen , habe ich Farben- schatzungen rnit unbewaffnetem Auge angestellt und als Hellig- 6. keitsgrenze, bis zu welcher die Farben erkennbar sind, ge- Zur Ermittelung des Einflusses der Instrumente auf funden : die Farbe bieten sich die von mir mittelst dreier Fernrohre Bei orangefarbenen Sternen etwa zmg erlangten Beobachtungsreihen dar. I) gelblichen n 2 2.0 . Tab. 2. Unterschiede der Farben: 4 2. - t. R. Farbe 5’” )I iiberh. -- 4m - 1?4 - 1 c2 - - - 1.1 -1.0 -1OI - IF”I - I .2 -0.8 -0.4 -0.6 - 1.2 -0.8 -0.7 -0.6 -0.9 -1.1 - 1.0 - 0.6 -0.7 -0.8 - 0.8 -0.4 -0.5 - 0.6 - - 0.3 - 0.4 ~- uberh. -0.9 Hiernach sind im Durchschnitt alle Farben im kleinen Ausser mit jenen beiden Fernglasern habe ich noch t. R. intensiver gesehen worden als im 4 Z., aber nicht in eine dritte Reihe rnit dem Sucher des 4 Zollers zu erlangen gleichem Maasse, vielmehr ist deutlich ein Gang nach den gesucht. Sie ist jedoch nicht ganz zu Stande gekommen und Farben vorbanden. Hingegen bleibt das Verhaltniss der deshalb aus dem Cataloge fortgeblieben. Ich gebe sie hier. Der Farbenangaben der beiden Instrurnente innerhalb jeder Farben- Sucher (S) besitzt 2 7 mm Objectivoffnung bei 24 cm Brenn- stufe ziernlich constant fir die verschiedenen Helligkeiten. weite und 9 mal. Vergrosserung. Stern Vgl. Farbe Stern Vgl. Farbe Stern Vgl. Farbe Stern Vgl. Farbe I I 1 I - 1 1 I 1 a Andr. 4 2C5 d Andr. 5 700 @ Andr. 4 7?1 B Arietis 4 3:o 6 Cass. 4 3.0 a Cass. 7 6.7 a Urs. min. 2 4.8 y Andr. 3 6.3 7 Pegasi 3 2.0 y D 3 3.3 a Triang. 2 4.5 a Arietis 9 6.3 145 365 7 46 - - - - - - Stern Vgl. Farbe Stern ilgl. Farbe Stern Irgl. Farbe - - - ~ - /3 Triang. 2 3C5 5 Aurigae 3 7?0 a Ursae 4 y Sagittae 2 7% a Ceti 4 7.3 as 5 4. I 79 2 Y Cygni 4 4.9 y Persei 2 6.0 y Orionis 2 2.0 a Bootis 4 aa 4 3.4 e' 4 7.3 /3 Tauri 4 I .8 @ Coronae 2 y Delphini 2 6.3 B B' 9 2.7 a Orionis 4 6.6 a> 2 E Cygni 4 6.0 a' I 4.3 ,9 Aurigae 5 2.2 w Herculis 5 5. 2 5.8 d* 6 7.8 rj Geminorum 2 7.8 8 CYPi 4 E Pegasi 2 7.3 5. 3 3.0 ru) 2 7 *8 a Sagittae 2 'I> 2 7.0 ED 2 2 2 2 0.5 YB 3.0 BR 1, 5.5 7 Tauri 2 6.0 a 2 4 2.3 y Aquilae 3 Pm 2 5-5 a2 7 6.4 a Canis min. 2 4.0 d Cygni 3 Bs 7.3 L Aurigae I1 1.3 8 Geminorum 5 5.7 a Aquilae 4 n2 I .8 2 I: Es 3 5.0 8 Ursae 2.5 Bei der Bearbeitung der folgenden Tabellen sind die wachweisbar ist. Mit steigender Vergrosserung nimmt die sechs Verhderlichen E Aurigae, a Cassiopeiae, T,I Geminorum, Intensitat der Farbe zu und zwar die der weisslichen wiel a Orionis, /3 Pegasi und e Persei fortgelassen und die Farben starker als die der rothgelben. des S. bei der Eintheilung als Grundlage angenommen worden. 7. Tab. 3. Unterschiede der Farben: S. - 4 2. (56 St.) - Zur Ermittelung des Einflusses des Mondscheins steht mir nur ein geringes Material zur Verfiigung. Ich pflegte Farbe I" 2" 3" 4'" 5" iiberh. 1 1 1 I 1 I nur hochst selten in der Zeit uber das I. Viertel hinaus zu beobachten, weil die Helligkeit der Sterne dann zu sehr IC - - - 105 - - IC5 verringert wurde. 2 - +0?6 +O.I - +0.4 3 OCO +0.8 +0.4 - oC4 +0.6 In den beiden folgenden Tafeln sind die Differenzen +0.8 +0.7 - +0.8 im Sinne (Beob. im 3) - (Beob. in Abwesenheit des 3) +0.9 - +0.4 +0.8 zu verstehen, sodass also eine negative Differenz anzeigt, +0.7 +0.7 +0.6 +0.6 dass die Farbe im Mondschein heller geschatzt wurde. tiberh. 1 +0.7 I +0.8 1.+0.6 I +0.5 1 +0.9 1 +o.i Tab. 5. Einfluss des Mondscheins. - t. R. -Tab. 4. -Unterschiede der Farben:- S. - t. R. (55 St.) Farbe tiberh. Farbe I" 4" tiberh. 2c +0?03 3 +0.02 -0?02 - +o.o 1 lC - - -2C5 - - 2?5 4 -0.i5 -0.23 +oCg5 -0.
Load more

Recommended publications
  • Lurking in the Shadows: Wide-Separation Gas Giants As Tracers of Planet Formation
    Lurking in the Shadows: Wide-Separation Gas Giants as Tracers of Planet Formation Thesis by Marta Levesque Bryan In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy CALIFORNIA INSTITUTE OF TECHNOLOGY Pasadena, California 2018 Defended May 1, 2018 ii © 2018 Marta Levesque Bryan ORCID: [0000-0002-6076-5967] All rights reserved iii ACKNOWLEDGEMENTS First and foremost I would like to thank Heather Knutson, who I had the great privilege of working with as my thesis advisor. Her encouragement, guidance, and perspective helped me navigate many a challenging problem, and my conversations with her were a consistent source of positivity and learning throughout my time at Caltech. I leave graduate school a better scientist and person for having her as a role model. Heather fostered a wonderfully positive and supportive environment for her students, giving us the space to explore and grow - I could not have asked for a better advisor or research experience. I would also like to thank Konstantin Batygin for enthusiastic and illuminating discussions that always left me more excited to explore the result at hand. Thank you as well to Dimitri Mawet for providing both expertise and contagious optimism for some of my latest direct imaging endeavors. Thank you to the rest of my thesis committee, namely Geoff Blake, Evan Kirby, and Chuck Steidel for their support, helpful conversations, and insightful questions. I am grateful to have had the opportunity to collaborate with Brendan Bowler. His talk at Caltech my second year of graduate school introduced me to an unexpected population of massive wide-separation planetary-mass companions, and lead to a long-running collaboration from which several of my thesis projects were born.
    [Show full text]
  • A Hot Subdwarf-White Dwarf Super-Chandrasekhar Candidate
    A hot subdwarf–white dwarf super-Chandrasekhar candidate supernova Ia progenitor Ingrid Pelisoli1,2*, P. Neunteufel3, S. Geier1, T. Kupfer4,5, U. Heber6, A. Irrgang6, D. Schneider6, A. Bastian1, J. van Roestel7, V. Schaffenroth1, and B. N. Barlow8 1Institut fur¨ Physik und Astronomie, Universitat¨ Potsdam, Haus 28, Karl-Liebknecht-Str. 24/25, D-14476 Potsdam-Golm, Germany 2Department of Physics, University of Warwick, Coventry, CV4 7AL, UK 3Max Planck Institut fur¨ Astrophysik, Karl-Schwarzschild-Straße 1, 85748 Garching bei Munchen¨ 4Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106, USA 5Texas Tech University, Department of Physics & Astronomy, Box 41051, 79409, Lubbock, TX, USA 6Dr. Karl Remeis-Observatory & ECAP, Astronomical Institute, Friedrich-Alexander University Erlangen-Nuremberg (FAU), Sternwartstr. 7, 96049 Bamberg, Germany 7Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA 91125, USA 8Department of Physics and Astronomy, High Point University, High Point, NC 27268, USA *[email protected] ABSTRACT Supernova Ia are bright explosive events that can be used to estimate cosmological distances, allowing us to study the expansion of the Universe. They are understood to result from a thermonuclear detonation in a white dwarf that formed from the exhausted core of a star more massive than the Sun. However, the possible progenitor channels leading to an explosion are a long-standing debate, limiting the precision and accuracy of supernova Ia as distance indicators. Here we present HD 265435, a binary system with an orbital period of less than a hundred minutes, consisting of a white dwarf and a hot subdwarf — a stripped core-helium burning star.
    [Show full text]
  • Winter Constellations
    Winter Constellations *Orion *Canis Major *Monoceros *Canis Minor *Gemini *Auriga *Taurus *Eradinus *Lepus *Monoceros *Cancer *Lynx *Ursa Major *Ursa Minor *Draco *Camelopardalis *Cassiopeia *Cepheus *Andromeda *Perseus *Lacerta *Pegasus *Triangulum *Aries *Pisces *Cetus *Leo (rising) *Hydra (rising) *Canes Venatici (rising) Orion--Myth: Orion, the great ​ ​ hunter. In one myth, Orion boasted he would kill all the wild animals on the earth. But, the earth goddess Gaia, who was the protector of all animals, produced a gigantic scorpion, whose body was so heavily encased that Orion was unable to pierce through the armour, and was himself stung to death. His companion Artemis was greatly saddened and arranged for Orion to be immortalised among the stars. Scorpius, the scorpion, was placed on the opposite side of the sky so that Orion would never be hurt by it again. To this day, Orion is never seen in the sky at the same time as Scorpius. DSO’s ● ***M42 “Orion Nebula” (Neb) with Trapezium A stellar ​ ​ ​ nursery where new stars are being born, perhaps a thousand stars. These are immense clouds of interstellar gas and dust collapse inward to form stars, mainly of ionized hydrogen which gives off the red glow so dominant, and also ionized greenish oxygen gas. The youngest stars may be less than 300,000 years old, even as young as 10,000 years old (compared to the Sun, 4.6 billion years old). 1300 ly. ​ ​ 1 ● *M43--(Neb) “De Marin’s Nebula” The star-forming ​ “comma-shaped” region connected to the Orion Nebula. ● *M78--(Neb) Hard to see. A star-forming region connected to the ​ Orion Nebula.
    [Show full text]
  • 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.
    [Show full text]
  • Exodata: a Python Package to Handle Large Exoplanet Catalogue Data
    ExoData: A Python package to handle large exoplanet catalogue data Ryan Varley Department of Physics & Astronomy, University College London 132 Hampstead Road, London, NW1 2PS, United Kingdom [email protected] Abstract Exoplanet science often involves using the system parameters of real exoplanets for tasks such as simulations, fitting routines, and target selection for proposals. Several exoplanet catalogues are already well established but often lack a version history and code friendly interfaces. Software that bridges the barrier between the catalogues and code enables users to improve the specific repeatability of results by facilitating the retrieval of exact system parameters used in an arti- cles results along with unifying the equations and software used. As exoplanet science moves towards large data, gone are the days where researchers can recall the current population from memory. An interface able to query the population now becomes invaluable for target selection and population analysis. ExoData is a Python interface and exploratory analysis tool for the Open Exoplanet Cata- logue. It allows the loading of exoplanet systems into Python as objects (Planet, Star, Binary etc) from which common orbital and system equations can be calculated and measured parame- ters retrieved. This allows researchers to use tested code of the common equations they require (with units) and provides a large science input catalogue of planets for easy plotting and use in research. Advanced querying of targets are possible using the database and Python programming language. ExoData is also able to parse spectral types and fill in missing parameters according to programmable specifications and equations. Examples of use cases are integration of equations into data reduction pipelines, selecting planets for observing proposals and as an input catalogue to large scale simulation and analysis of planets.
    [Show full text]
  • The Extragalactic Distance Scale
    The Extragalactic Distance Scale Published in "Stellar astrophysics for the local group" : VIII Canary Islands Winter School of Astrophysics. Edited by A. Aparicio, A. Herrero, and F. Sanchez. Cambridge ; New York : Cambridge University Press, 1998 Calibration of the Extragalactic Distance Scale By BARRY F. MADORE1, WENDY L. FREEDMAN2 1NASA/IPAC Extragalactic Database, Infrared Processing & Analysis Center, California Institute of Technology, Jet Propulsion Laboratory, Pasadena, CA 91125, USA 2Observatories, Carnegie Institution of Washington, 813 Santa Barbara St., Pasadena CA 91101, USA The calibration and use of Cepheids as primary distance indicators is reviewed in the context of the extragalactic distance scale. Comparison is made with the independently calibrated Population II distance scale and found to be consistent at the 10% level. The combined use of ground-based facilities and the Hubble Space Telescope now allow for the application of the Cepheid Period-Luminosity relation out to distances in excess of 20 Mpc. Calibration of secondary distance indicators and the direct determination of distances to galaxies in the field as well as in the Virgo and Fornax clusters allows for multiple paths to the determination of the absolute rate of the expansion of the Universe parameterized by the Hubble constant. At this point in the reduction and analysis of Key Project galaxies H0 = 72km/ sec/Mpc ± 2 (random) ± 12 [systematic]. Table of Contents INTRODUCTION TO THE LECTURES CEPHEIDS BRIEF SUMMARY OF THE OBSERVED PROPERTIES OF CEPHEID
    [Show full text]
  • Instrumental Methods for Professional and Amateur
    Instrumental Methods for Professional and Amateur Collaborations in Planetary Astronomy Olivier Mousis, Ricardo Hueso, Jean-Philippe Beaulieu, Sylvain Bouley, Benoît Carry, Francois Colas, Alain Klotz, Christophe Pellier, Jean-Marc Petit, Philippe Rousselot, et al. To cite this version: Olivier Mousis, Ricardo Hueso, Jean-Philippe Beaulieu, Sylvain Bouley, Benoît Carry, et al.. Instru- mental Methods for Professional and Amateur Collaborations in Planetary Astronomy. Experimental Astronomy, Springer Link, 2014, 38 (1-2), pp.91-191. 10.1007/s10686-014-9379-0. hal-00833466 HAL Id: hal-00833466 https://hal.archives-ouvertes.fr/hal-00833466 Submitted on 3 Jun 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Instrumental Methods for Professional and Amateur Collaborations in Planetary Astronomy O. Mousis, R. Hueso, J.-P. Beaulieu, S. Bouley, B. Carry, F. Colas, A. Klotz, C. Pellier, J.-M. Petit, P. Rousselot, M. Ali-Dib, W. Beisker, M. Birlan, C. Buil, A. Delsanti, E. Frappa, H. B. Hammel, A.-C. Levasseur-Regourd, G. S. Orton, A. Sanchez-Lavega,´ A. Santerne, P. Tanga, J. Vaubaillon, B. Zanda, D. Baratoux, T. Bohm,¨ V. Boudon, A. Bouquet, L. Buzzi, J.-L. Dauvergne, A.
    [Show full text]
  • Downloads/ Astero2007.Pdf) and by Aerts Et Al (2010)
    This work is protected by copyright and other intellectual property rights and duplication or sale of all or part is not permitted, except that material may be duplicated by you for research, private study, criticism/review or educational purposes. Electronic or print copies are for your own personal, non- commercial use and shall not be passed to any other individual. No quotation may be published without proper acknowledgement. For any other use, or to quote extensively from the work, permission must be obtained from the copyright holder/s. i Fundamental Properties of Solar-Type Eclipsing Binary Stars, and Kinematic Biases of Exoplanet Host Stars Richard J. Hutcheon Submitted in accordance with the requirements for the degree of Doctor of Philosophy. Research Institute: School of Environmental and Physical Sciences and Applied Mathematics. University of Keele June 2015 ii iii Abstract This thesis is in three parts: 1) a kinematical study of exoplanet host stars, 2) a study of the detached eclipsing binary V1094 Tau and 3) and observations of other eclipsing binaries. Part I investigates kinematical biases between two methods of detecting exoplanets; the ground based transit and radial velocity methods. Distances of the host stars from each method lie in almost non-overlapping groups. Samples of host stars from each group are selected. They are compared by means of matching comparison samples of stars not known to have exoplanets. The detection methods are found to introduce a negligible bias into the metallicities of the host stars but the ground based transit method introduces a median age bias of about -2 Gyr.
    [Show full text]
  • Arxiv:0908.2624V1 [Astro-Ph.SR] 18 Aug 2009
    Astronomy & Astrophysics Review manuscript No. (will be inserted by the editor) Accurate masses and radii of normal stars: Modern results and applications G. Torres · J. Andersen · A. Gim´enez Received: date / Accepted: date Abstract This paper presents and discusses a critical compilation of accurate, fun- damental determinations of stellar masses and radii. We have identified 95 detached binary systems containing 190 stars (94 eclipsing systems, and α Centauri) that satisfy our criterion that the mass and radius of both stars be known to ±3% or better. All are non-interacting systems, so the stars should have evolved as if they were single. This sample more than doubles that of the earlier similar review by Andersen (1991), extends the mass range at both ends and, for the first time, includes an extragalactic binary. In every case, we have examined the original data and recomputed the stellar parameters with a consistent set of assumptions and physical constants. To these we add interstellar reddening, effective temperature, metal abundance, rotational velocity and apsidal motion determinations when available, and we compute a number of other physical parameters, notably luminosity and distance. These accurate physical parameters reveal the effects of stellar evolution with un- precedented clarity, and we discuss the use of the data in observational tests of stellar evolution models in some detail. Earlier findings of significant structural differences between moderately fast-rotating, mildly active stars and single stars, ascribed to the presence of strong magnetic and spot activity, are confirmed beyond doubt. We also show how the best data can be used to test prescriptions for the subtle interplay be- tween convection, diffusion, and other non-classical effects in stellar models.
    [Show full text]
  • GTO Keypad Manual, V5.001
    ASTRO-PHYSICS GTO KEYPAD Version v5.xxx Please read the manual even if you are familiar with previous keypad versions Flash RAM Updates Keypad Java updates can be accomplished through the Internet. Check our web site www.astro-physics.com/software-updates/ November 11, 2020 ASTRO-PHYSICS KEYPAD MANUAL FOR MACH2GTO Version 5.xxx November 11, 2020 ABOUT THIS MANUAL 4 REQUIREMENTS 5 What Mount Control Box Do I Need? 5 Can I Upgrade My Present Keypad? 5 GTO KEYPAD 6 Layout and Buttons of the Keypad 6 Vacuum Fluorescent Display 6 N-S-E-W Directional Buttons 6 STOP Button 6 <PREV and NEXT> Buttons 7 Number Buttons 7 GOTO Button 7 ± Button 7 MENU / ESC Button 7 RECAL and NEXT> Buttons Pressed Simultaneously 7 ENT Button 7 Retractable Hanger 7 Keypad Protector 8 Keypad Care and Warranty 8 Warranty 8 Keypad Battery for 512K Memory Boards 8 Cleaning Red Keypad Display 8 Temperature Ratings 8 Environmental Recommendation 8 GETTING STARTED – DO THIS AT HOME, IF POSSIBLE 9 Set Up your Mount and Cable Connections 9 Gather Basic Information 9 Enter Your Location, Time and Date 9 Set Up Your Mount in the Field 10 Polar Alignment 10 Mach2GTO Daytime Alignment Routine 10 KEYPAD START UP SEQUENCE FOR NEW SETUPS OR SETUP IN NEW LOCATION 11 Assemble Your Mount 11 Startup Sequence 11 Location 11 Select Existing Location 11 Set Up New Location 11 Date and Time 12 Additional Information 12 KEYPAD START UP SEQUENCE FOR MOUNTS USED AT THE SAME LOCATION WITHOUT A COMPUTER 13 KEYPAD START UP SEQUENCE FOR COMPUTER CONTROLLED MOUNTS 14 1 OBJECTS MENU – HAVE SOME FUN!
    [Show full text]
  • Planets and Exoplanets
    NASE Publications Planets and exoplanets Planets and exoplanets Rosa M. Ros, Hans Deeg International Astronomical Union, Technical University of Catalonia (Spain), Instituto de Astrofísica de Canarias and University of La Laguna (Spain) Summary This workshop provides a series of activities to compare the many observed properties (such as size, distances, orbital speeds and escape velocities) of the planets in our Solar System. Each section provides context to various planetary data tables by providing demonstrations or calculations to contrast the properties of the planets, giving the students a concrete sense for what the data mean. At present, several methods are used to find exoplanets, more or less indirectly. It has been possible to detect nearly 4000 planets, and about 500 systems with multiple planets. Objetives - Understand what the numerical values in the Solar Sytem summary data table mean. - Understand the main characteristics of extrasolar planetary systems by comparing their properties to the orbital system of Jupiter and its Galilean satellites. The Solar System By creating scale models of the Solar System, the students will compare the different planetary parameters. To perform these activities, we will use the data in Table 1. Planets Diameter (km) Distance to Sun (km) Sun 1 392 000 Mercury 4 878 57.9 106 Venus 12 180 108.3 106 Earth 12 756 149.7 106 Marte 6 760 228.1 106 Jupiter 142 800 778.7 106 Saturn 120 000 1 430.1 106 Uranus 50 000 2 876.5 106 Neptune 49 000 4 506.6 106 Table 1: Data of the Solar System bodies In all cases, the main goal of the model is to make the data understandable.
    [Show full text]
  • Annual Report / Rapport Annuel / Jahresbericht 1996
    Annual Report / Rapport annuel / Jahresbericht 1996 ✦ ✦ ✦ E U R O P E A N S O U T H E R N O B S E R V A T O R Y ES O✦ 99 COVER COUVERTURE UMSCHLAG Beta Pictoris, as observed in scattered light Beta Pictoris, observée en lumière diffusée Beta Pictoris, im Streulicht bei 1,25 µm (J- at 1.25 microns (J band) with the ESO à 1,25 microns (bande J) avec le système Band) beobachtet mit dem adaptiven opti- ADONIS adaptive optics system at the 3.6-m d’optique adaptative de l’ESO, ADONIS, au schen System ADONIS am ESO-3,6-m-Tele- telescope and the Observatoire de Grenoble télescope de 3,60 m et le coronographe de skop und dem Koronographen des Obser- coronograph. l’observatoire de Grenoble. vatoriums von Grenoble. The combination of high angular resolution La combinaison de haute résolution angu- Die Kombination von hoher Winkelauflö- (0.12 arcsec) and high dynamical range laire (0,12 arcsec) et de gamme dynamique sung (0,12 Bogensekunden) und hohem dy- (105) allows to image the disk to only 24 AU élevée (105) permet de reproduire le disque namischen Bereich (105) erlaubt es, die from the star. Inside 50 AU, the main plane jusqu’à seulement 24 UA de l’étoile. A Scheibe bis zu einem Abstand von nur 24 AE of the disk is inclined with respect to the l’intérieur de 50 UA, le plan principal du vom Stern abzubilden. Innerhalb von 50 AE outer part. Observers: J.-L. Beuzit, A.-M.
    [Show full text]