Ultraviolet Spectroscopy of Old Novae and Symbiotic
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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. -
Unknown Amorphous Carbon II. LRS SPECTRA the Sample Consists Of
Table I A summary of the spectral -features observed in the LRS spectra of the three groups o-f carbon stars. The de-finition o-f the groups is given in the text. wavelength Xmax identification Group I B - 12 urn E1 9.7 M™ Silicate 12 - 23 jim E IB ^m Silicate Group II < 8.5 M"i A C2H2 CS? 12 - 16 f-i/n A 13.7 - 14 Mm C2H2 HCN? 8 - 10 Mm E 8.6 M"i Unknown 10 - 13 Mm E 11.3 - 11 .7 M«> SiC Group III 10 - 13 MJn E 11.3 - 11 .7 tun SiC B - 23 Htn C Amorphous carbon 1 The letter in this column indicates the nature o-f the -feature: A = absorption; E = emission; C indicates the presence of continuum opacity. II. LRS SPECTRA The sample consists of 304 carbon stars with entries in the LRS catalog (Papers I-III). The LRS spectra have been divided into three groups. Group I consists of nine stars with 9.7 and 18 tun silicate features in their LRS spectra pointing to oxygen-rich dust in the circumstellar shell. These sources are discussed in Paper I. The remaining stars all have spectra with carbon-rich dust features. Using NIR photometry we have shown that in the group II spectra the stellar photosphere is the dominant continuum. The NIR color temperature is of the order of 25OO K. Paper II contains a discussion of sources with this class of spectra. The continuum in the group III spectra is probably due to amorphous carbon dust. -
JOHN R. THORSTENSEN Address
CURRICULUM VITAE: JOHN R. THORSTENSEN Address: Department of Physics and Astronomy Dartmouth College 6127 Wilder Laboratory Hanover, NH 03755-3528; (603)-646-2869 [email protected] Undergraduate Studies: Haverford College, B. A. 1974 Astronomy and Physics double major, High Honors in both. Graduate Studies: Ph. D., 1980, University of California, Berkeley Astronomy Department Dissertation : \Optical Studies of Faint Blue X-ray Stars" Graduate Advisor: Professor C. Stuart Bowyer Employment History: Department of Physics and Astronomy, Dartmouth College: { Professor, July 1991 { present { Associate Professor, July 1986 { July 1991 { Assistant Professor, September 1980 { June 1986 Research Assistant, Space Sciences Lab., U.C. Berkeley, 1975 { 1980. Summer Student, National Radio Astronomy Observatory, 1974. Summer Student, Bartol Research Foundation, 1973. Consultant, IBM Corporation, 1973. (STARMAP program). Honors and Awards: Phi Beta Kappa, 1974. National Science Foundation Graduate Fellow, 1974 { 1977. Dorothea Klumpke Roberts Award of the Berkeley Astronomy Dept., 1978. Professional Societies: American Astronomical Society Astronomical Society of the Pacific International Astronomical Union Lifetime Publication List * \Can Collapsed Stars Close the Universe?" Thorstensen, J. R., and Partridge, R. B. 1975, Ap. J., 200, 527. \Optical Identification of Nova Scuti 1975." Raff, M. I., and Thorstensen, J. 1975, P. A. S. P., 87, 593. \Photometry of Slow X-ray Pulsars II: The 13.9 Minute Period of X Persei." Margon, B., Thorstensen, J., Bowyer, S., Mason, K. O., White, N. E., Sanford, P. W., Parkes, G., Stone, R. P. S., and Bailey, J. 1977, Ap. J., 218, 504. \A Spectrophotometric Survey of the A 0535+26 Field." Margon, B., Thorstensen, J., Nelson, J., Chanan, G., and Bowyer, S. -
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. -
Správa O Činnosti Organizácie SAV Za Rok 2017
Astronomický ústav SAV Správa o činnosti organizácie SAV za rok 2017 Tatranská Lomnica január 2018 Obsah osnovy Správy o činnosti organizácie SAV za rok 2017 1. Základné údaje o organizácii 2. Vedecká činnosť 3. Doktorandské štúdium, iná pedagogická činnosť a budovanie ľudských zdrojov pre vedu a techniku 4. Medzinárodná vedecká spolupráca 5. Vedná politika 6. Spolupráca s VŠ a inými subjektmi v oblasti vedy a techniky 7. Spolupráca s aplikačnou a hospodárskou sférou 8. Aktivity pre Národnú radu SR, vládu SR, ústredné orgány štátnej správy SR a iné organizácie 9. Vedecko-organizačné a popularizačné aktivity 10. Činnosť knižnično-informačného pracoviska 11. Aktivity v orgánoch SAV 12. Hospodárenie organizácie 13. Nadácie a fondy pri organizácii SAV 14. Iné významné činnosti organizácie SAV 15. Vyznamenania, ocenenia a ceny udelené organizácii a pracovníkom organizácie SAV 16. Poskytovanie informácií v súlade so zákonom o slobodnom prístupe k informáciám 17. Problémy a podnety pre činnosť SAV PRÍLOHY A Zoznam zamestnancov a doktorandov organizácie k 31.12.2017 B Projekty riešené v organizácii C Publikačná činnosť organizácie D Údaje o pedagogickej činnosti organizácie E Medzinárodná mobilita organizácie F Vedecko-popularizačná činnosť pracovníkov organizácie SAV Správa o činnosti organizácie SAV 1. Základné údaje o organizácii 1.1. Kontaktné údaje Názov: Astronomický ústav SAV Riaditeľ: Mgr. Martin Vaňko, PhD. Zástupca riaditeľa: Mgr. Peter Gömöry, PhD. Vedecký tajomník: Mgr. Marián Jakubík, PhD. Predseda vedeckej rady: RNDr. Luboš Neslušan, CSc. Člen snemu SAV: Mgr. Marián Jakubík, PhD. Adresa: Astronomický ústav SAV, 059 60 Tatranská Lomnica http://www.ta3.sk Tel.: 052/7879111 Fax: 052/4467656 E-mail: [email protected] Názvy a adresy detašovaných pracovísk: Astronomický ústav - Oddelenie medziplanetárnej hmoty Dúbravská cesta 9, 845 04 Bratislava Vedúci detašovaných pracovísk: Astronomický ústav - Oddelenie medziplanetárnej hmoty prof. -
The NTT Provides the Deepest Look Into Space 6
The NTT Provides the Deepest Look Into Space 6. A. PETERSON, Mount Stromlo Observatory,Australian National University, Canberra S. D'ODORICO, M. TARENGHI and E. J. WAMPLER, ESO The ESO New Technology Telescope r on La Silla has again proven its extraor- - dinary abilities. It has now produced the "deepest" view into the distant regions of the Universe ever obtained with ground- or space-based telescopes. Figure 1 : This picture is a reproduction of a I.1 x 1.1 arcmin portion of a composite im- age of forty-one 10-minute exposures in the V band of a field at high galactic latitude in the constellation of Sextans (R.A. loh 45'7 Decl. -0' 143. The individual images were obtained with the EMMI imager/spectrograph at the Nas- myth focus of the ESO 3.5-m New Technolo- gy Telescope using a 1000 x 1000 pixel Thomson CCD. This combination gave a full field of 7.6 x 7.6 arcmin and a pixel size of 0.44 arcsec. The average seeing during these exposures was 1.0 arcsec. The telescope was offset between the indi- vidual exposures so that the sky background could be used to flat-field the frame. This procedure also removed the effects of cos- mic rays and blemishes in the CCD. More than 97% of the objects seen in this sub- field are galaxies. For the brighter galax- ies, there is good agreement between the galaxy counts of Tyson (1988, Astron. J., 96, 1) and the NTT counts for the brighter galax- ies. -
National Radio Astronomy Observatory Quarterly
Qs V'O6?-AzIJJ NATIONAL RADIO ASTRONOMY OBSERVATORY QUARTERLY REPORT January 1 - March 31, 1990 APr TABLE OF CONTENTS A. TELESCOPE USAGE .1.. .. ... ............................... 1 B. 140-FOOT TELESCOPE1 ... ........ ............................. 1 C. 12-METER TELESCOPE6 ......... ............................. 6 D. VERY LARGE ARRAY9 .. ........ .............................. 9 E. SCIENTIFIC HIGHLIGHTS .. ........ ............................ 20 F. PUBLICATIONS ... ........ ................................ 21 G. CENTRAL DEVELOPMENT LABORATORY . ....... ....................... 21 H. GREEN BANK ELECTRONICS . ........ ........................... 23 I. 12-METER ELECTRONICS . ........ .............................. 25 J. VLA ELECTRONICS .. ........ ............................... 25 K. AIPS .. ........ .................................... 28 L. VLA COMPUTER .. ....... ................................ 28 M. VERY LONG BASELINE ARRAY . ........ .......................... 29 N. PERSONNEL ... .......... .................................. 32 APPENDIX A: LIST OF NRAO PREPRINTS A. TELESCOPE USAGE The NRAO telescopes have been scheduled for research and maintenance in the following manner during the first quarter of 1990. 140-ft 12-meter VIA Scheduled observing (hours) 1935.00 1772.25 1624.6 Scheduled maintenance and equipment changes 193.5 116.25 264.6 Scheduled tests and calibrations 127.25 261.50 261.6 Time lost 103.75 366.25 78.0 Actual observing 1831.25 1496.00 1546.7 B. 140-FOOT TELESCOPE The following line programs were conducted during the quarter. No. Observer(s) Program B-492 Bell, M. (Herzberg) Spectral survey of IRC+10216 over the Feldman, P (Herzberg) range 22.0-24.5 GHz. Matthews, H. (Herzberg) B-524 Bell, M. (Herzberg) . Studies at 17.5-24.5 GHz of heavy Avery, L. (Herzberg) molecule chemistry in shocked and Feldman, P. (Herzberg) unshocked gas in Orion. Matthews, H. (Herzberg) B-492 Bell, M. (Herzberg) Spectral survey of IRC+10216 over the Feldman, P. (Herzberg) range 22.0-24.5 GHz. Matthews, H. (Herzberg) B-525 Bell, M. -
2014-08 AUG.Pdf
August First Light Newsletter 1 message August, 2014 Issue 122 AlachuaAstronomyClub.org North Central Florida's Amateur Astronomy Club Serving Alachua County since 1987 BREAKING NEWS -- ROSETTA HAS JUST ARRIVED AT COMET 67/P Member Member Astronomical League Initiated in late 1993 by Europe and the USA, and launched in 2004, the International Rosetta Mission is an historic first: Send a spacecraft to chase and orbit a comet, ride along as the comet plunges sun ward to learn how a frozen comet transforms by the Sun's warmth, and dispatch a controlled lander to make in situ measurements and make first images Member from a comet's surface. NASA Night Sky Network Ten years later Rosetta has now arrived at Comet 67P/Churyumov- Gerasimenko and just successfully made orbit today, 2014 August 6! Unfortunately, global events have foreshadowed this memorable event and news media have largely ignored this impressive space mission. AAC Member photo: The Rosetta comet mission may be the beginning of a story that will tell more about us -- both about our origins and evolution. (Hence, its name "rosetta" for the black basalt stone with inscriptions giving the first clues to deciphering Egyptian hieroglyphics.) Pictures received over past weeks are remarkable with the latest in the past 24 hours showing awesome and incredible detail including views that show the comet is a connected binary object rotating as a unit in 12 hours. Anyone see the glorious pairing of Venus and Jupiter this morning (2016 Aug. 18)? For images see http://www.esa.int/ spaceinimages/Missions/ Except when Mars is occasionally brighter Rosetta than Jupiter, these two planets are the brightest nighttime sky objects (discounting Example Image (Aug. -
The Orbital Ephemeris of the Classical Nova RR Pictoris: Presence of A
Draft version August 5, 2018 Preprint typeset using LATEX style AASTeX6 v. 1.0 THE ORBITAL EPHEMERIS OF THE CLASSICAL NOVA RR PICTORIS: PRESENCE OF A THIRD BODY? N. Vogt1, M. R. Schreiber1, F.-J. Hambsch3,4, G. Retamales1, C. Tappert1, L. Schmidtobreick2 & I. Fuentes-Morales1 1Instituto de F´ısica y Astronom´ıa, Universidad de Valpara´ıso, Valpara´ıso, Chile 2European Southern Observatory, Santiago 19, Chile, Casilla 1900 3Vereniging Voor Sterrenkunde (VVS), Oude Bleken 12, 2400 Mol, Belgium 4 American Association of Variable Star Observers, 49 Bay State Rd., Cambridge, MA02138, USA ABSTRACT The ex-nova RR Pic presents a periodic hump in its light curve which is considered to refer to its orbital period. Analyzing all available epochs of these hump maxima in the literature, and combining them with those from new light curves obtained in 2013 and 2014, we establish an unique cycle count scheme valid during the past 50 years, and derive an ephemeris with the orbital period 0.145025959(15) days. The O - C diagram of this linear ephemeris reveals systematic deviations which could have different causes. One of them could be a light-travel-time effect caused by the presence of a hypothetical third body near the star/brown dwarf mass limit, with an orbital period of the order of 70 years. We also examine the difficulty of the problematic of detecting sub-stellar or planetary companions of close red- dwarf white-dwarf binaries (including cataclysmic variables), and discuss other possible mechanisms responsible for the observed deviations in O - C. For RR Pic, we propose strategies in order to solve this question by new observations. -
La Constellation Du Cocher Ou Auriga ( Latin )
DansDans lala ss éérierie lesles constellationsconstellations lala constellationconstellation dudu CocherCocher ouou AurigaAuriga (( LatinLatin )) - Repérage - Caractéristiques - Histoire Constellation d’hiver, le Cocher fait partie des 48 constellations originellement répertoriées par Ptolémée dans son Almageste*. Superficie 657 deg² à comparer aux 1 255 deg² d’Hercule par exemple… * L'Almageste (qui est l'arabisation du grec ancien megistos (byblos) signifiant grand (livre)) est une œuvre de Claude Ptolémée datant du IIe siècle étant la somme des connaissances les plus avancées de son époque Patrice D écembre 2008 en mathématiques et en astronomie. L'Almageste contient également un catalogue d'étoiles. LocalisationLocalisation RepRep ééragerage • Le Cocher est une constellation très étendue traversée par la Voie Lactée et riche en amas d'étoiles, la constellation du Cocher se signale d'abord par son étoile principale, Capella. • Si la Grande Ourse est visible, Capella se situe dans la direction pointée par le grand chariot, à une vingtaine de degrés vers l’ Est. • Capella - Presque aussi brillante que Véga de la Lyre et d'une luminosité supérieure à celle de Rigel d'Orion. FormeForme • Partiellement circumpolaire, observée depuis une latitude de 45° Nord, la constellation dessine sensiblement un pentagone formé dans le sens des aiguilles d'une montre par Capella α Aur, ς Aur, ß du Taureau située juste à la limite sud de la constellation, puis en remontant vers le nord, θ Aur et ß Aur. • L'autre élément remarquable de la constellation est formé par les trois petites "chevrettes" η, ζ et ε Aur, qui forment un triangle serré au Sud de Capella. CaractCaract ééristiquesristiques CapellaCapella Capella (α Aurigae) appartient au groupe de tête des étoiles les plus éclatantes de nos nuits. -
September 2020 BRAS Newsletter
A Neowise Comet 2020, photo by Ralf Rohner of Skypointer Photography Monthly Meeting September 14th at 7:00 PM, via Jitsi (Monthly meetings are on 2nd Mondays at Highland Road Park Observatory, temporarily during quarantine at meet.jit.si/BRASMeets). GUEST SPEAKER: NASA Michoud Assembly Facility Director, Robert Champion What's In This Issue? President’s Message Secretary's Summary Business Meeting Minutes Outreach Report Asteroid and Comet News Light Pollution Committee Report Globe at Night Member’s Corner –My Quest For A Dark Place, by Chris Carlton Astro-Photos by BRAS Members Messages from the HRPO REMOTE DISCUSSION Solar Viewing Plus Night Mercurian Elongation Spooky Sensation Great Martian Opposition Observing Notes: Aquila – The Eagle 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 27 September 2020 President’s Message Welcome to September. You may have noticed that this newsletter is showing up a little bit later than usual, and it’s for good reason: release of the newsletter will now happen after the monthly business meeting so that we can have a chance to keep everybody up to date on the latest information. Sometimes, this will mean the newsletter shows up a couple of days late. But, the upshot is that you’ll now be able to see what we discussed at the recent business meeting and have time to digest it before our general meeting in case you want to give some feedback. Now that we’re on the new format, business meetings (and the oft neglected Light Pollution Committee Meeting), are going to start being open to all members of the club again by simply joining up in the respective chat rooms the Wednesday before the first Monday of the month—which I encourage people to do, especially if you have some ideas you want to see the club put into action. -
Ludwig Neidhart
© Dr. Ludwig Neidhart, 1998, 2007 „Als die Zeit erfüllt war ...“ Ein Diskussionsbeitrag zu Grundproblemen der biblischen Weihnachtgeschichte und der Datierung der Geburt Christi von Ludwig Neidhart (überarbeitete Version, Stand 07.04.2019) Erstmals erschienen in: Brücke zum Menschen Nr. 133, 1. Quartal 1998 Leicht überarbeitete Version in: Pro Sancta Ecclesia Nr. 21, 2007, S. 20–110 Auszug mit dem Titel ‚Die Magier und der Stern’ in: Dörthe Emig-Herchen (Hg.), Silberglanz in stillen Gassen. Weihnachts-Anthologie 2007, Frankfurt a.M., 2007, S. 221–246 Inhaltsverzeichnis 1. Wie kam man auf den 25. Dezember?...................................................................................................2 2. Wie alt ist das Geburtsfest Christi am 25. Dezember?........................................................................3 3. Frühchristliche Traditionen über den Geburtstag Jesu......................................................................4 4. Kann Christus im Dezember geboren sein?.........................................................................................7 5. Biblische Chronologie des Lebens Christi............................................................................................8 5.1. Die Dauer des öffentlichen Wirkens Jesu......................................................................................8 5.2. Jesus starb am 7. April des Jahres 30.............................................................................................9 5.3. Exkurs über die Stunde der Kreuzigung.....................................................................................13