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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. -
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 -
Stars and Their Spectra: an Introduction to the Spectral Sequence Second Edition James B
Cambridge University Press 978-0-521-89954-3 - Stars and Their Spectra: An Introduction to the Spectral Sequence Second Edition James B. Kaler Index More information Star index Stars are arranged by the Latin genitive of their constellation of residence, with other star names interspersed alphabetically. Within a constellation, Bayer Greek letters are given first, followed by Roman letters, Flamsteed numbers, variable stars arranged in traditional order (see Section 1.11), and then other names that take on genitive form. Stellar spectra are indicated by an asterisk. The best-known proper names have priority over their Greek-letter names. Spectra of the Sun and of nebulae are included as well. Abell 21 nucleus, see a Aurigae, see Capella Abell 78 nucleus, 327* ε Aurigae, 178, 186 Achernar, 9, 243, 264, 274 z Aurigae, 177, 186 Acrux, see Alpha Crucis Z Aurigae, 186, 269* Adhara, see Epsilon Canis Majoris AB Aurigae, 255 Albireo, 26 Alcor, 26, 177, 241, 243, 272* Barnard’s Star, 129–130, 131 Aldebaran, 9, 27, 80*, 163, 165 Betelgeuse, 2, 9, 16, 18, 20, 73, 74*, 79, Algol, 20, 26, 176–177, 271*, 333, 366 80*, 88, 104–105, 106*, 110*, 113, Altair, 9, 236, 241, 250 115, 118, 122, 187, 216, 264 a Andromedae, 273, 273* image of, 114 b Andromedae, 164 BDþ284211, 285* g Andromedae, 26 Bl 253* u Andromedae A, 218* a Boo¨tis, see Arcturus u Andromedae B, 109* g Boo¨tis, 243 Z Andromedae, 337 Z Boo¨tis, 185 Antares, 10, 73, 104–105, 113, 115, 118, l Boo¨tis, 254, 280, 314 122, 174* s Boo¨tis, 218* 53 Aquarii A, 195 53 Aquarii B, 195 T Camelopardalis, -
Publications of the Astronomical Society of the Pacific Vol. 106 1994 March No. 697 Publications of the Astronomical Society Of
Publications of the Astronomical Society of the Pacific Vol. 106 1994 March No. 697 Publications of the Astronomical Society of the Pacific 106: 209-238, 1994 March Invited Review Paper The DQ Herculis Stars Joseph Patterson Department of Astronomy, Columbia University, 538 West 120th Street, New York, New York 10027 Electronic mail: [email protected] Received 1993 September 2; accepted 1993 December 9 ABSTRACT. We review the properties of the DQ Herculis stars: cataclysmic variables containing an accreting, magnetic, rapidly rotating white dwarf. These stars are characterized by strong X-ray emission, high-excitation spectra, and very stable optical and X-ray pulsations in their light curves. There is considerable resemblance to their more famous cousins, the AM Herculis stars, but the latter class is additionally characterized by spin-orbit synchronism and the presence of strong circular polarization. We list eighteen stars passing muster as certain or very likely DQ Her stars. The rotational periods range from 33 s to 2.0 hr. Additional periods can result when the rotating searchlight illuminates other structures in the binary. A single hypothesis explains most of the observed properties: magnetically channeled accretion within a truncated disk. Some accretion flow still seems to proceed directly to the magnetosphere, however. The white dwarfs' magnetic moments are in the range 1032-1034 G cm3, slightly weaker than in AM Her stars but with some probable overlap. The more important reason why DQ Hers have broken synchronism is probably their greater accretion rate and orbital separation. The observed Lx/L v values are surprisingly low for a radially accreting white dwarf, suggesting that most of the accretion energy is not radiated in a strong shock above the magnetic pole. -
Episodic Absorption in the Outflow of the Old Nova V603 Aquilae
Mon. Not. R. Astron. Soc. 318, 368±374 (2000) Episodic absorption in the outflow of the old nova V603 Aquilae Raman K. Prinja,1w Christian Knigge,2² F. A. Ringwald3³ and Richard A. Wade4 1Department of Physics and Astronomy, University College London, Gower St, London WC1E 6BT 2Department of Astronomy, Columbia University, 555 West 120th Street, New York, NY 10027, USA 3Department of Physics and Space Sciences, Florida Institute of Technology, 150 West University Boulevard, Melbourne, FL 32901-6988, USA 4Department of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802-6305, USA Accepted 2000 May 12. Received 2000 April 19; in original form 2000 February 17 ABSTRACT We report on the time-dependent behaviour of ultraviolet spectral lines in Hubble Space Telescope Goddard High-Resolution Spectrograph data of the classical nova V603 Aql. In particular, episodic blueshifted absorption (extending to ,22500 km s21) is present, with a variability time-scale down to ,1 min. The data provide a rare opportunity to study the rapid evolution of absorption structures that may be associated with accretion-disc winds in cataclysmic variables. At least three absorption events are recorded (at blueward velocities only) over ,5 h, each lasting ,10±15 min. The derived velocity, acceleration and optical depth properties provide an empirical picture of stochastically variable structures in the outflow, with no evidence for short-term (less than ,1 h) cyclic or modulated behaviour in the overall absorption properties. In contrast, the emission components of the ultraviolet resonance lines are very stable in velocity and strength in this low-inclination system. -
WZ Sagittae Space Weather—Global Warming
Journal of Earth Science and Engineering 7 (2017) 154-174 doi: 10.17265/2159-581X/2017.03.004 D DAVID PUBLISHING WZ Sagittae Space Weather—Global Warming William Sokeland Retired, Heat Transfer Expert, Spacecraft and Turbine Engines, Oakland City, Indiana47660, USA Abstract: The planet responds thermally to the impacts of nova WZ Sagittae debris by heating and cooling. The result in the first 19 years of the nova WZ Sagittae cycle is global warming that is hemi-spherically dependent and is detectable in South America ice core data and Antarctica surface mass balance data. Planetary thermal data are correlated in the past by calculating the debris impact times from the super outbursts times of nova WZ Sagittae. The shape of the arctic ice cap is dependent on the 220 degree path of the debris and does not exist southward between the western extension and eastern termini of nova WZ Sagittae that define the Arctic heating path. Future global heating from nova WZ Sagittae will begin in 2020-2021. The increase of 6 to 8 magnitude unusual earthquakes in recent years is the results of nova WZ Sagittae and SN 1054 debris impact. Unusual occurrences in the biosphere indicate the starting time of impacting supernova debris streams. The Antarctic sea ice distribution in November of 2016 defines the termini of maximum particle concentration impact from supernova 1006 in the southern hemisphere. The killing heat in India of the northern hemisphere is associated with the western terminus of this supernova. Novas and supernovas times of impact correlate with plague outbreaks in the western USA marking the particles in the debris streams as the cause of the disease. -
CONSTRAINTS on MID-INFRARED CYCLOTRON EMISSION Thomas E
The Astrophysical Journal, 656:444 Y 455, 2007 February 10 # 2007. The American Astronomical Society. All rights reserved. Printed in U.S.A. SPITZER IRS SPECTROSCOPY OF INTERMEDIATE POLARS: CONSTRAINTS ON MID-INFRARED CYCLOTRON EMISSION Thomas E. Harrison1 and Ryan K. Campbell1 Department of Astronomy, New Mexico State University, Las Cruces, NM; [email protected], [email protected] Steve B. Howell WIYN Observatory and National Optical Astronomy Observatories, Tucson, AZ; [email protected] France A. Cordova Institute of Geophysics and Planetary Physics, Department of Physics, University of California, Riverside, CA; [email protected] and Axel D. Schwope Astrophysikalisches Institut Potsdam, Potsdam, Germany; [email protected] Received 2006 September 29; accepted 2006 November 1 ABSTRACT We present Spitzer IRS observations of 11 intermediate polars (IPs). Spectra covering the wavelength range from 5.2 to 14 m are presented for all 11 objects, and longer wavelength spectra are presented for three objects (AE Aqr, EX Hya, and V1223 Sgr). We also present new, moderate-resolution (R 2000) near-infrared spectra for five of the program objects. We find that, in general, the mid-infrared spectra are consistent with simple power laws that extend from the optical into the mid-infrared. There is no evidence for discrete cyclotron emission features in the near- or mid-infrared spectra for any of the IPs investigated, nor for infrared excesses at k 12 m. However, AE Aqr, and possibly EX Hya and V1223 Sgr, do show longer wavelength excesses. We have used a cyclotron modeling code to put limits on the amount of such emission for magnetic field strengths of 1 B 7 MG. -
Information Bulletin on Variable Stars
COMMISSIONS AND OF THE I A U INFORMATION BULLETIN ON VARIABLE STARS Nos April November EDITORS L SZABADOS K OLAH TECHNICAL EDITOR A HOLL TYPESETTING MB POCS ADMINISTRATION Zs KOVARI EDITORIAL BOARD E Budding HW Duerb eck EF Guinan P Harmanec chair D Kurtz KC Leung C Maceroni NN Samus advisor C Sterken advisor H BUDAPEST XI I Box HUNGARY URL httpwwwkonkolyhuIBVSIBVShtml HU ISSN 2 IBVS 4701 { 4800 COPYRIGHT NOTICE IBVS is published on b ehalf of the th and nd Commissions of the IAU by the Konkoly Observatory Budap est Hungary Individual issues could b e downloaded for scientic and educational purp oses free of charge Bibliographic information of the recent issues could b e entered to indexing sys tems No IBVS issues may b e stored in a public retrieval system in any form or by any means electronic or otherwise without the prior written p ermission of the publishers Prior written p ermission of the publishers is required for entering IBVS issues to an electronic indexing or bibliographic system to o IBVS 4701 { 4800 3 CONTENTS WOLFGANG MOSCHNER ENRIQUE GARCIAMELENDO GSC A New Variable in the Field of V Cassiop eiae :::::::::: JM GOMEZFORRELLAD E GARCIAMELENDO J GUARROFLO J NOMENTORRES J VIDALSAINZ Observations of Selected HIPPARCOS Variables ::::::::::::::::::::::::::: JM GOMEZFORRELLAD HD a New Low Amplitude Variable Star :::::::::::::::::::::::::: ME VAN DEN ANCKER AW VOLP MR PEREZ D DE WINTER NearIR Photometry and Optical Sp ectroscopy of the Herbig Ae Star AB Au rigae ::::::::::::::::::::::::::::::::::::::::::::::::::: -
PDF Hosted at the Radboud Repository of the Radboud University Nijmegen
PDF hosted at the Radboud Repository of the Radboud University Nijmegen The following full text is a publisher's version. For additional information about this publication click this link. http://hdl.handle.net/2066/159310 Please be advised that this information was generated on 2021-10-09 and may be subject to change. Multi-wavelength Accretion Studies of Cataclysmic Variable Stars Proefschrift ter verkrijging van de graad van doctor aan de Radboud Universiteit Nijmegen op gezag van de rector magnificus prof. dr. J.H.J.M. van Krieken, volgens besluit van het college van decanen in het openbaar te verdedigen op Maandag 3 Oktober 2016 om 10:30 uur precies door Deanne Larissa Coppejans geboren op 7 Februari 1988 te Zuid-Afrika Promotoren: Prof. dr. P.J. Groot Prof. dr. P.A. Woudt University of Cape Town, SA Copromotor: Dr. E.G. Körding Manuscriptcommissie: Prof. dr. R. Kleiss Prof. dr. F.W.M. Verbunt Prof. dr. R.P. Fender University of Oxford, UK Prof. dr. A. Achterberg Dr. S. Scaringi MPE, Duitsland c 2016, Deanne Larissa Coppejans Multi-wavelength Accretion Studies of Cataclysmic Variable Stars Thesis, Radboud University Nijmegen Printed by Ipskamp Printing Illustrated; with bibliographic information and Dutch summary ISBN: 978-94-028-0320-4 Contents 1 Introduction 1 1.1 Cataclysmic Variables..................................1 1.1.1 Structure.....................................1 1.1.2 Mass Transfer...................................3 1.1.3 Formation and Evolution............................4 1.2 Dwarf Novae and Novalikes...............................6 1.2.1 Dwarf Nova Outburst Mechanism........................7 1.2.2 Superoutburst Mechanism............................9 1.3 Radio Emission from Cataclysmic Variables..................... -
European Southern Observatory
+ +lES+ OBSERVATORY (()) EUROPEAN SOUTHERN + COVER COUVfRTURf UMSCHLAG This cover highlights two IIhljor events Cette couverture met en evidence deux Dieser Umschl<lg hebt zwei 'wichl ofthe ye<lr, Clflmin<ltion ofsever<ll ye<lrs' evenements m<ljeurs de l',mnee - points Ereignisse des j,z/nes herv0/' - Hö of prep<lr<ltory development work. The Clflmirhlrzts de plusieurs <lrmees de tr<l punkte j<llnel,mger 'lHn'bereitender f contr<lct for the Unit Telescopes' M<lin V"'tX de developpements pnip,maoires. wicklungs<lrbeiten. Der Vertr,lg iiber Structure W,IS signed on September 24 Le contr,ll rel<ltzj"'ll<l structure principde Struktltr der vier finzelteleskope (see ,l!so the introdltction on p<lge 11). in des telescopes individuels du VLT <I ete VLT wurde <Im 24. September Imt October it W<lS decided to <ldopt ,m en signe le 24 septembre (voir l'intraduc zeichnet (siehe <!uch die finleitung I, c!osure type for the VLT which IIhlxi tion et LI photo 'Il<l p<lge 11). En octobre, d,ls Foto 'I/tf Seite 11). im Oktober m<llly protects the telescope <lrul its sensi l<l deeision fut prise d'<ldopter Itri type de die Entscheidung ji'ir einen Gelltiude tive prillhlry mirror while en<lbling ex bitiment qui, d'une p<lrt, ojji'e une pro ji'ir d,IS VLT, der einerseits einen md cellent therrn<ll <lnd <lir flow control to tection m<lximde du telescope et de son mden Schutz der Teleskope und ih elimin,lle deterior<ltion of seeing by this mirair princip,1! delic<lt et (jui, d'<lutre empfirul/ichen H'I/Iptspiegel ge·ühi.