Variable Star Section Circular 75
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Perseus Perseus
Lateinischer Name: Deutscher Name: Per Perseus Perseus Atlas (2000.0) Karte Cambridge Star Kulmination um 2, 3 Atlas Mitternacht: Benachbarte 1, 4, Sky Atlas Sternbilder: 5 And Ari Aur Cam Cas 7. November Tau Tri Deklinationsbereich: 30° ... 59° Fläche am Himmel: 615° 2 Mythologie und Geschichte: Akrisios war der König von Argos und hatte eine hübsche Tochter namens Danae. Das Orakel von Delphi prophezeite ihm, sein Enkelsohn werde ihn einst töten. Aus Furcht vor diesem Orakelspruch ließ Akrisios seine Tochter Danae in einen Turm einschließen, damit sie keinen Mann empfangen könne. Akrisios konnte natürlich nicht wissen, dass Zeus selbst sich der liebreizenden Danae nähern wollte. Zeus tat dies auch und nahm dazu die Form eines goldenen Regens an, der durch die Wände, Fugen, Ritzen und Fenster drang. Danae gebar einen Sohn, welcher "Der aus fließendem Gold entstandene" oder auch "Der Goldgeborene" genannt wurde - eben den Perseus. Akrisios blieb dies natürlich nicht lange verborgen und er ließ seine Tochter und sein Enkelkind in einen Kasten einnageln, der dann ins Meer geworfen wurde. Danae und Perseus trieben lange Zeit auf dem Meer, bis sie schließlich an der Küste der steinigen Insel Seriphos strandeten und aus ihrem Gefängnis befreit wurden. Auf dieser Insel herrschte Polydektes, der bald jahrelang um die schöne Danae warb, jedoch vergebens. Entweder um Danae doch noch zur Ehe zu zwingen oder um Perseus aus dem Weg zu schaffen, schickte er den inzwischen zum Jüngling herangewachsenen Sohn der Danae aus, eine tödliche Aufgabe zu erledigen. Er solle das Haupt der Medusa zu holen. Die Medusa war eine der Gorgonen, eine der drei Töchter des Phorkys, die mit Schlangenhaaren ausgestattet waren und einen versteinernden Blick werfen konnten. -
Appendix: Spectroscopy of Variable Stars
Appendix: Spectroscopy of Variable Stars As amateur astronomers gain ever-increasing access to professional tools, the science of spectroscopy of variable stars is now within reach of the experienced variable star observer. In this section we shall examine the basic tools used to perform spectroscopy and how to use the data collected in ways that augment our understanding of variable stars. Naturally, this section cannot cover every aspect of this vast subject, and we will concentrate just on the basics of this field so that the observer can come to grips with it. It will be noticed by experienced observers that variable stars often alter their spectral characteristics as they vary in light output. Cepheid variable stars can change from G types to F types during their periods of oscillation, and young variables can change from A to B types or vice versa. Spec troscopy enables observers to monitor these changes if their instrumentation is sensitive enough. However, this is not an easy field of study. It requires patience and dedication and access to resources that most amateurs do not possess. Nevertheless, it is an emerging field, and should the reader wish to get involved with this type of observation know that there are some excellent guides to variable star spectroscopy via the BAA and the AAVSO. Some of the workshops run by Robin Leadbeater of the BAA Variable Star section and others such as Christian Buil are a very good introduction to the field. © Springer Nature Switzerland AG 2018 M. Griffiths, Observer’s Guide to Variable Stars, The Patrick Moore 291 Practical Astronomy Series, https://doi.org/10.1007/978-3-030-00904-5 292 Appendix: Spectroscopy of Variable Stars Spectra, Spectroscopes and Image Acquisition What are spectra, and how are they observed? The spectra we see from stars is the result of the complete output in visible light of the star (in simple terms). -
International Registration Designating India Trade Marks Journal No: 1960 , 10/08/2020 Class 1
International Registration designating India Trade Marks Journal No: 1960 , 10/08/2020 Class 1 Priority claimed from 07/10/2019; Application No. : 88644417 ;United States of America 4513772 31/03/2020 [International Registration No. : 1528222] Thermo Fisher Scientific (Bremen) GmbH Hanna-Kunath-Strasse 11 28199 Bremen Germany Proposed to be Used IR DIVISION Kits comprised of enzymes, reagents, nucleotides, and assays for scientific or research purposes. 6449 Trade Marks Journal No: 1960 , 10/08/2020 Class 1 4534058 24/03/2020 [International Registration No. : 1468883] Evonik Operations GmbH Rellinghauser Str. 1 - 11 45128 Essen Germany Proposed to be Used IR DIVISION Cl.1;Chemical substances, chemical materials and chemical preparations, and natural elements, included in this class, for use in industry; detergents for use in manufacture and industry; filtering media of chemical and non-chemical substances included in this class. 6450 Trade Marks Journal No: 1960 , 10/08/2020 Class 1 Priority claimed from 30/10/2019; Application No. : 2019-138709 ;Japan 4535241 31/03/2020 [International Registration No. : 1535335] Sanyo Chemical Industries, Ltd. 11-1, Ikkyo Nomoto-cho, Higashiyama-ku, Kyoto-shi Kyoto 605-0995 Japan Proposed to be Used IR DIVISION Industrial chemicals; surface-active chemical agents; chemical additives for fuel; chemical additives for lubricating oils; chemical additives improving the viscosity index of lubricating oil; plasticizers; chemical preparations for metal finishing; antibacterial agents for industrial use; resin -
December 2019 BRAS Newsletter
A Monthly Meeting December 11th at 7PM at HRPO (Monthly meetings are on 2nd Mondays, Highland Road Park Observatory). Annual Christmas Potluck, and election of officers. What's In This Issue? President’s Message Secretary's Summary Outreach Report Asteroid and Comet News Light Pollution Committee Report Globe at Night Member’s Corner – The Green Odyssey Messages from the HRPO Friday Night Lecture Series Science Academy Solar Viewing Stem Expansion Transit of Murcury Edge of Night Natural Sky Conference Observing Notes: Perseus – Rescuer Of Andromeda, or the Hero & Mythology Like this newsletter? See PAST ISSUES online back to 2009 Visit us on Facebook – Baton Rouge Astronomical Society Baton Rouge Astronomical Society Newsletter, Night Visions Page 2 of 25 December 2019 President’s Message I would like to thank everyone for having me as your president for the last two years . I hope you have enjoyed the past two year as much as I did. We had our first Members Only Observing Night (MOON) at HRPO on Sunday, 29 November,. New officers nominated for next year: Scott Cadwallader for President, Coy Wagoner for Vice- President, Thomas Halligan for Secretary, and Trey Anding for Treasurer. Of course, the nominations are still open. If you wish to be an officer or know of a fellow member who would make a good officer contact John Nagle, Merrill Hess, or Craig Brenden. We will hold our annual Baton Rouge “Gastronomical” Society Christmas holiday feast potluck and officer elections on Monday, December 9th at 7PM at HRPO. I look forward to seeing you all there. ALCon 2022 Bid Preparation and Planning Committee: We’ll meet again on December 14 at 3:00.pm at Coffee Call, 3132 College Dr F, Baton Rouge, LA 70808, UPCOMING BRAS MEETINGS: Light Pollution Committee - HRPO, Wednesday December 4th, 6:15 P.M. -
GEORGE HERBIG and Early Stellar Evolution
GEORGE HERBIG and Early Stellar Evolution Bo Reipurth Institute for Astronomy Special Publications No. 1 George Herbig in 1960 —————————————————————– GEORGE HERBIG and Early Stellar Evolution —————————————————————– Bo Reipurth Institute for Astronomy University of Hawaii at Manoa 640 North Aohoku Place Hilo, HI 96720 USA . Dedicated to Hannelore Herbig c 2016 by Bo Reipurth Version 1.0 – April 19, 2016 Cover Image: The HH 24 complex in the Lynds 1630 cloud in Orion was discov- ered by Herbig and Kuhi in 1963. This near-infrared HST image shows several collimated Herbig-Haro jets emanating from an embedded multiple system of T Tauri stars. Courtesy Space Telescope Science Institute. This book can be referenced as follows: Reipurth, B. 2016, http://ifa.hawaii.edu/SP1 i FOREWORD I first learned about George Herbig’s work when I was a teenager. I grew up in Denmark in the 1950s, a time when Europe was healing the wounds after the ravages of the Second World War. Already at the age of 7 I had fallen in love with astronomy, but information was very hard to come by in those days, so I scraped together what I could, mainly relying on the local library. At some point I was introduced to the magazine Sky and Telescope, and soon invested my pocket money in a subscription. Every month I would sit at our dining room table with a dictionary and work my way through the latest issue. In one issue I read about Herbig-Haro objects, and I was completely mesmerized that these objects could be signposts of the formation of stars, and I dreamt about some day being able to contribute to this field of study. -
Cycle 9 Approved Programs
Cycle 9 Approved Programs TYPE OF SCIENCE FIRST NAME LAST NAME INSTITUTION COUNTRY TITLE PROPOSAL CATEGORY A Morphological and Multicolor HST Survey for Ultrafaint Quasars, Sampling A Scott Anderson AR University of Washington United States AGN Broad Redshift Range Antonio Aparicio GO Instituto de Astrofi sica de Canarias Spain GAL Phoenix: "halo/disk" structures in dwarf galaxies John Bahcall GO Institute for Advanced Study United States HS Observing the next nearby supernova Ultraviolet Spectroscopy of Hot Horizontal-Branch Stars in the Globular Cluster Bradford Behr GO California Institute of Technology United States HS M13 David Bennett GO University of Notre Dame United States SP Confirmation of Black Hole, Planetary, and Binary Microlensing Events Klaus P. Beuermann GO Universitaets-Sternwarte Goettingen Germany HS FGS parallaxes of magnetic CVs Luciana Bianchi GO The Johns Hopkins University United States SP The Massive Star Content of NGC 6822 Torsten Boeker SNAP Space Telescope Science Institute United States GAL A Census of Nuclear Star Clusters in Late-Type Spiral Galaxies Ann Boesgaard GO Institute for Astronomy, University of Hawaii United States CS The Nucleosynthesis of Boron - Benchmarks for the Galactic Disk Howard Bond GO Space Telescope Science Institute United States CS WFPC2 Observations of Astrophysically Important Visual Binaries Howard Bond GO Space Telescope Science Institute United States HS Sakurai's Novalike Object: Real-Time Monitoring of a Stellar Thermal Pulse Amanda Bosh AR Lowell Observatory United States -
Abstracts of Talks 1
Abstracts of Talks 1 INVITED AND CONTRIBUTED TALKS (in order of presentation) Milky Way and Magellanic Cloud Surveys for Planetary Nebulae Quentin A. Parker, Macquarie University I will review current major progress in PN surveys in our own Galaxy and the Magellanic clouds whilst giving relevant historical context and background. The recent on-line availability of large-scale wide-field surveys of the Galaxy in several optical and near/mid-infrared passbands has provided unprecedented opportunities to refine selection techniques and eliminate contaminants. This has been coupled with surveys offering improved sensitivity and resolution, permitting more extreme ends of the PN luminosity function to be explored while probing hitherto underrepresented evolutionary states. Known PN in our Galaxy and LMC have been significantly increased over the last few years due primarily to the advent of narrow-band imaging in important nebula lines such as H-alpha, [OIII] and [SIII]. These PNe are generally of lower surface brightness, larger angular extent, in more obscured regions and in later stages of evolution than those in most previous surveys. A more representative PN population for in-depth study is now available, particularly in the LMC where the known distance adds considerable utility for derived PN parameters. Future prospects for Galactic and LMC PN research are briefly highlighted. Local Group Surveys for Planetary Nebulae Laura Magrini, INAF, Osservatorio Astrofisico di Arcetri The Local Group (LG) represents the best environment to study in detail the PN population in a large number of morphological types of galaxies. The closeness of the LG galaxies allows us to investigate the faintest side of the PN luminosity function and to detect PNe also in the less luminous galaxies, the dwarf galaxies, where a small number of them is expected. -
Astronomical Coordinate Systems
Appendix 1 Astronomical Coordinate Systems A basic requirement for studying the heavens is being able to determine where in the sky things are located. To specify sky positions, astronomers have developed several coordinate systems. Each sys- tem uses a coordinate grid projected on the celestial sphere, which is similar to the geographic coor- dinate 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 The equatorial coordinate system is probably the most widely used celestial coordinate system. It is also the most closely related to the geographic coordinate system because they use the same funda- mental plane and poles. The projection of the Earth’s equator onto the celestial sphere is called the celestial equator. Similarly, projecting the geographic poles onto the celestial sphere defines the north and south celestial poles. However, there is an important difference between the equatorial and geographic coordinate sys- tems: the geographic system is fixed to the Earth and 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 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. -
January 2021
the vol. 48 no. 01 Skyscraper January 2021 AMATEUR ASTRONOMICAL SOCIETY OF RHODE ISLAND 47 PEEPTOAD ROAD NORTH SCITUATE, RHODE ISLAND 02857 WWW.THESKYSCRAPERS.ORG In This Issue: A Behind the Scenes Look at 2 President’s Message Hubble Space Telescope Operations 3 Astronomical Highlights for 2021 4 Geminids report for 12/13/2020 An Online Presentation by Mike Wenz 6 Clock Face Curiosity: Saturday, January 2, 7:00pm EST via Zoom The Numeral IIII 7 Check Your Sky’s Contact Steve Hubbard ([email protected]) for Quality with Orion! Zoom Meeting link and information. 8 Cluster and Reflection Many people have seen the wonderful performed by the Space Shuttle. Mike is Nebula in Perseus: IC 348 pictures that the Hubble Space Telescope intimately involved with the day to day op- 10 Star Party Update & has produced over the 29 years of it's oper- erations of the telescope and is the one re- Observing Reports ation so far. However, few people have seen sponsible to investigate any pointing prob- what is truly involved in the day to day op- lems or issues that come up on a daily basis. 11 From the Archives eration of a telescope that has been called a Mike has used the information provided 12 The Sun, Moon & National Treasure. This talk will take a look by the Fine Guidance Sensors to serendip- Planets in January behind the scenes and explain how the tele- itously discover hundreds of new double scope is operated and what it takes to make stars and was involved in a study using the 13 Astrophoto Gallery the science observations that lead to all of Fine Guidance Sensors that led to the dis- 16 Starry Scoop the discoveries Hubble has been involved covery of the smallest Kuiper Belt object in. -
Precision Diagnostics of Pulsation and Evolution in Helium-Rich Low-Mass Stars
Precision Diagnostics of Pulsation and Evolution in Helium-Rich Low-Mass Stars A dissertation submitted to the University of Dublin for the degree of Doctor of Philosophy Pamela Martin, B.A. (Mod). Armagh Observatory and Planetarium & Trinity College Dublin 2019 School of Physics University of Dublin Trinity College ii Declaration I declare that this thesis has not been submitted as an exercise for a degree at this or any other university and it is entirely my own work. I agree to deposit this thesis in the University's open access institutional repository or allow the Library to do so on my behalf, subject to Irish Copyright Legislation and Trinity College Library conditions of use and acknowledgement. Name: Pamela Martin Signature: ........................................ Date: .......................... Abstract In this thesis we discuss many types of low mass stars linked by their un- usually low hydrogen atmospheric abundance, usually completely replaced with helium. We begin with the hot subdwarfs; subdwarf O and B (sdB, sdO) stars are low-mass core helium burning stars with extremely low-mass hydrogen envelopes. Their atmospheres are generally helium deficient; how- ever a minority have extremely helium-rich surfaces. An additional fraction have an intermediate surface-helium abundance, occasionally accompanied by peculiar abundances of other elements. LS IV−14◦116 is a non-radially pulsating slowly-rotating chemically-peculiar helium-rich sdB with a 4 dex surface excess of zirconium, yttrium, and strontium. The pulsations are un- expected and unexplained, as the star is 6 000K hotter than the blue edge of the hot subdwarf g-mode instability strip. The presence of pulsations offers a rare opportunity to study the structure of the photosphere. -
Pg Sagittae, a Test Op the Theory Op Evolution Op Double Shell Source Stars
PG SAGITTAE, A TEST OP THE THEORY OP EVOLUTION OP DOUBLE SHELL SOURCE STARS Yu. A# Padeyev Astronomical Council USSR Academy of Sciences PG Sge is a unique stellar object possessing a number of unusual properties which are as follows: (1) PG Sge is a core of a planetary nebula, (2) at least since 1894 this star has crossed the HR diagram from the left to the right, (3) the atmosphere of PG Sge was enriched in s-elements, (4) PG Sge is a pulsating variable the period of which progressively Increases from 15 days in 1962 to 110 days in 1980. As it was primarily supposed by Paczynski (1971) PG Sge mores in the HR diagram along the horisontal loop due to a helium shell flash in its interior. This hypothesis provides not only the explanation of enriched surface abundances of s-elements but allows also to estimate both the distance and the age of the planetary nebula surrounding PG Sge* According to Plannery and Herbig (1973) the expansion velocity and the angular radius of the planetary nebula are 34 km/a and 18 arc sec, respectively* Thus, the age of the planetary nebula r is related to the distance d by log r (yr) ■ 0.400 + log d (pc) (1) Supposing that the planetary nebula was formed at the pre ceding helium f^ash, the interflash period - core mass relation (Paczynski, 1975) and the core mass - luminosity relation (Paczynski. 1970) can be used for obtaining another relation between the age of the planetary nebula and its distance: log r - 5.201 - 4.79 -10~8 d2. -
The Evolution and Nucleosynthesis of Thermally Pulsing Asymptotic Giant Branch Stars
The Evolution and Nucleosynthesis of Thermally Pulsing Asymptotic Giant Branch Stars Richard James Stancliffe Churchill College Institute of Astronomy University of Cambridge Thesis submitted for the Degree of Doctor of Philosophy at the University of Cambridge · 2005 · Declaration I hereby declare that my thesis entitled The Evolution and Nucleosynthesis of Thermally Pulsing Asymptotic Giant Branch Stars is not substantially the same as any that I have submitted for a degree or diploma or other qualification at any other University. I further state that no part of my thesis has already been or is being concurrently submitted for any such degree, diploma or other qualification. This dissertation is the result of my own work and includes nothing which is the outcome of work done in collaboration except where specifically indicated in the text. Those parts of this thesis which have been published or accepted for publication are as follows: • Material from chapters 2 and 3 has been published as: Stancliffe R. J., Tout C. A., Pols O. R., 2004, “Deep dredge-up in intermediate-mass thermally pulsing asymptotic giant branch stars”, Monthly Notices of the Royal Astronomical Society, 352, 984-992 and was completed in collaboration with these authors. • Material from chapter 4 has been published as: Stancliffe R. J., Izzard R. G., Tout C. A., 2005, “Third dredge-up in low-mass: solving the Large Magellanic Cloud carbon star mystery”, Monthly Notices of the Royal Astronomical Society, 356, L1-L5 and was completed in collaboration with these authors. • Material from chapter 5 has been published as: Stancliffe R. J., Lugaro M.