Nebular Metallicities in Isolated Dwarf Irregular Galaxies
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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. -
136, June 2008
British Astronomical Association VARIABLE STAR SECTION CIRCULAR No 136, June 2008 Contents Group Photograph, AAVSO/BAAVSS meeting ........................ inside front cover From the Director ............................................................................................... 1 Eclipsing Binary News ....................................................................................... 4 Experiments in the use of a DSLR camera for V photometry ............................ 5 Joint Meeting of the AAVSO and the BAAVSS ................................................. 8 Coordinated HST and Ground Campaigns on CVs ............................... 8 Eclipsing Binaries - Observational Challenges .................................................. 9 Peer to Peer Astronomy Education .................................................................. 10 AAVSO Acronyms De-mystified in Fifteen Minutes ...................................... 11 New Results on SW Sextantis Stars and Proposed Observing Campaign ........ 12 A Week in the Life of a Remote Observer ........................................................ 13 Finding Eclipsing Binaries in NSVS Data ......................................................... 13 British Variable Star Associations 1848-1908 .................................................. 14 “Chasing Rainbows” (The European Amateur Spectroscopy Scene) .............. 15 Long Term Monitoring and the Carbon Miras ................................................. 18 Cataclysmic Variables from Large Surveys: A Silent Revolution -
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. -
Guide Du Ciel Profond
Guide du ciel profond Olivier PETIT 8 mai 2004 2 Introduction hjjdfhgf ghjfghfd fg hdfjgdf gfdhfdk dfkgfd fghfkg fdkg fhdkg fkg kfghfhk Table des mati`eres I Objets par constellation 21 1 Androm`ede (And) Andromeda 23 1.1 Messier 31 (La grande Galaxie d'Androm`ede) . 25 1.2 Messier 32 . 27 1.3 Messier 110 . 29 1.4 NGC 404 . 31 1.5 NGC 752 . 33 1.6 NGC 891 . 35 1.7 NGC 7640 . 37 1.8 NGC 7662 (La boule de neige bleue) . 39 2 La Machine pneumatique (Ant) Antlia 41 2.1 NGC 2997 . 43 3 le Verseau (Aqr) Aquarius 45 3.1 Messier 2 . 47 3.2 Messier 72 . 49 3.3 Messier 73 . 51 3.4 NGC 7009 (La n¶ebuleuse Saturne) . 53 3.5 NGC 7293 (La n¶ebuleuse de l'h¶elice) . 56 3.6 NGC 7492 . 58 3.7 NGC 7606 . 60 3.8 Cederblad 211 (N¶ebuleuse de R Aquarii) . 62 4 l'Aigle (Aql) Aquila 63 4.1 NGC 6709 . 65 4.2 NGC 6741 . 67 4.3 NGC 6751 (La n¶ebuleuse de l’œil flou) . 69 4.4 NGC 6760 . 71 4.5 NGC 6781 (Le nid de l'Aigle ) . 73 TABLE DES MATIERES` 5 4.6 NGC 6790 . 75 4.7 NGC 6804 . 77 4.8 Barnard 142-143 (La tani`ere noire) . 79 5 le B¶elier (Ari) Aries 81 5.1 NGC 772 . 83 6 le Cocher (Aur) Auriga 85 6.1 Messier 36 . 87 6.2 Messier 37 . 89 6.3 Messier 38 . -
Bibliography from ADS File: Jordan-Stuart.Bib June 27, 2021 1
Bibliography from ADS file: jordan-stuart.bib Tremblay, P. E., Gentile-Fusillo, N., Cummings, J., et al., “White dwarfs in the August 16, 2021 Gaia era”, 2018IAUS..330..317T ADS Gentile Fusillo, N. P., Tremblay, P. E., Jordan, S., et al., “Can magnetic fields suppress convection in the atmosphere of cool white dwarfs? A case study on Gentile Fusillo, N. P., Tremblay, P. E., Cukanovaite, E., et al., “A catalogue of WD2105-820”, 2018MNRAS.473.3693G ADS white dwarfs in Gaia EDR3”, 2021arXiv210607669G ADS Gaia Collaboration, Clementini, G., Eyer, L., et al., “Gaia Data Re- Gaia Collaboration, Brown, A. G. A., Vallenari, A., et al., “Gaia Early Data lease 1. Testing parallaxes with local Cepheids and RR Lyrae stars”, Release 3. Summary of the contents and survey properties (Corrigendum)”, 2017A&A...605A..79G ADS 2021A&A...650C...3G ADS Moitinho, A., Krone-Martins, A., Savietto, H., et al., “Gaia Data Release 1. The Gaia Collaboration, Klioner, S. A., Mignard, F., et al., “Gaia Early archive visualisation service”, 2017A&A...605A..52M ADS Data Release 3. Acceleration of the Solar System from Gaia astrometry”, Kepler, S. O., Pelisoli, I., Jordan, S., et al., “VizieR Online Data Catalog: SDSS 2021A&A...649A...9G ADS magnetic white dwarf stars (Kepler+, 2013)”, 2017yCat..74292934K Gaia Collaboration, Antoja, T., McMillan, P. J., et al., “Gaia Early Data Release ADS 3. The Galactic anticentre”, 2021A&A...649A...8G ADS Gaia Collaboration, van Leeuwen, F., Vallenari, A., et al., “Gaia Data Release Gaia Collaboration, Luri, X., Chemin, L., et al., “Gaia Early Data 1. Open cluster astrometry: performance, limitations, and future prospects”, Release 3. -
Fy10 Budget by Program
AURA/NOAO FISCAL YEAR ANNUAL REPORT FY 2010 Revised Submitted to the National Science Foundation March 16, 2011 This image, aimed toward the southern celestial pole atop the CTIO Blanco 4-m telescope, shows the Large and Small Magellanic Clouds, the Milky Way (Carinae Region) and the Coal Sack (dark area, close to the Southern Crux). The 33 “written” on the Schmidt Telescope dome using a green laser pointer during the two-minute exposure commemorates the rescue effort of 33 miners trapped for 69 days almost 700 m underground in the San Jose mine in northern Chile. The image was taken while the rescue was in progress on 13 October 2010, at 3:30 am Chilean Daylight Saving time. Image Credit: Arturo Gomez/CTIO/NOAO/AURA/NSF National Optical Astronomy Observatory Fiscal Year Annual Report for FY 2010 Revised (October 1, 2009 – September 30, 2010) Submitted to the National Science Foundation Pursuant to Cooperative Support Agreement No. AST-0950945 March 16, 2011 Table of Contents MISSION SYNOPSIS ............................................................................................................ IV 1 EXECUTIVE SUMMARY ................................................................................................ 1 2 NOAO ACCOMPLISHMENTS ....................................................................................... 2 2.1 Achievements ..................................................................................................... 2 2.2 Status of Vision and Goals ................................................................................ -
IAU Division C Working Group on Star Names 2019 Annual Report
IAU Division C Working Group on Star Names 2019 Annual Report Eric Mamajek (chair, USA) WG Members: Juan Antonio Belmote Avilés (Spain), Sze-leung Cheung (Thailand), Beatriz García (Argentina), Steven Gullberg (USA), Duane Hamacher (Australia), Susanne M. Hoffmann (Germany), Alejandro López (Argentina), Javier Mejuto (Honduras), Thierry Montmerle (France), Jay Pasachoff (USA), Ian Ridpath (UK), Clive Ruggles (UK), B.S. Shylaja (India), Robert van Gent (Netherlands), Hitoshi Yamaoka (Japan) WG Associates: Danielle Adams (USA), Yunli Shi (China), Doris Vickers (Austria) WGSN Website: https://www.iau.org/science/scientific_bodies/working_groups/280/ WGSN Email: [email protected] The Working Group on Star Names (WGSN) consists of an international group of astronomers with expertise in stellar astronomy, astronomical history, and cultural astronomy who research and catalog proper names for stars for use by the international astronomical community, and also to aid the recognition and preservation of intangible astronomical heritage. The Terms of Reference and membership for WG Star Names (WGSN) are provided at the IAU website: https://www.iau.org/science/scientific_bodies/working_groups/280/. WGSN was re-proposed to Division C and was approved in April 2019 as a functional WG whose scope extends beyond the normal 3-year cycle of IAU working groups. The WGSN was specifically called out on p. 22 of IAU Strategic Plan 2020-2030: “The IAU serves as the internationally recognised authority for assigning designations to celestial bodies and their surface features. To do so, the IAU has a number of Working Groups on various topics, most notably on the nomenclature of small bodies in the Solar System and planetary systems under Division F and on Star Names under Division C.” WGSN continues its long term activity of researching cultural astronomy literature for star names, and researching etymologies with the goal of adding this information to the WGSN’s online materials. -
Arxiv:2001.10147V1
Magnetic fields in isolated and interacting white dwarfs Lilia Ferrario1 and Dayal Wickramasinghe2 Mathematical Sciences Institute, The Australian National University, Canberra, ACT 2601, Australia Adela Kawka3 International Centre for Radio Astronomy Research, Curtin University, Perth, WA 6102, Australia Abstract The magnetic white dwarfs (MWDs) are found either isolated or in inter- acting binaries. The isolated MWDs divide into two groups: a high field group (105 − 109 G) comprising some 13 ± 4% of all white dwarfs (WDs), and a low field group (B < 105 G) whose incidence is currently under investigation. The situation may be similar in magnetic binaries because the bright accretion discs in low field systems hide the photosphere of their WDs thus preventing the study of their magnetic fields’ strength and structure. Considerable research has been devoted to the vexed question on the origin of magnetic fields. One hypothesis is that WD magnetic fields are of fossil origin, that is, their progenitors are the magnetic main-sequence Ap/Bp stars and magnetic flux is conserved during their evolution. The other hypothesis is that magnetic fields arise from binary interaction, through differential rotation, during common envelope evolution. If the two stars merge the end product is a single high-field MWD. If close binaries survive and the primary develops a strong field, they may later evolve into the arXiv:2001.10147v1 [astro-ph.SR] 28 Jan 2020 magnetic cataclysmic variables (MCVs). The recently discovered population of hot, carbon-rich WDs exhibiting an incidence of magnetism of up to about 70% and a variability from a few minutes to a couple of days may support the [email protected] [email protected] [email protected] Preprint submitted to Journal of LATEX Templates January 29, 2020 merging binary hypothesis. -
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! -
Arxiv:2101.08801V1 [Astro-Ph.EP] 21 Jan 2021 Target Selection and Expanded Observational Techniques Have Type Stars (Zhou Et Al
DRAFT VERSION JANUARY 25, 2021 Typeset using LATEX twocolumn style in AASTeX63 A decade of radial-velocity monitoring of Vega and new limits on the presence of planets 1 2 2 3 2 SPENCER A. HURT , SAMUEL N. QUINN , DAVID W. LATHAM , ANDREW VANDERBURG , GILBERT A. ESQUERDO , 2 2 4, 5 2 2, ∗ MICHAEL L. CALKINS , PERRY BERLIND, RUTH ANGUS , CHRISTIAN A. LATHAM, AND GEORGE ZHOU 1Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309, USA 2Center for Astrophysics | Harvard & Smithsonian, 60 Garden St, Cambridge, MA 02138, USA 3Department of Astronomy, University of Wisconsin -Madison, 475 North Charter Street, Madison, WI 53706, USA 4Department of Astrophysics, American Museum of Natural History, 200 Central Park West, Manhattan, NY, USA 5Center for Computational Astrophysics, Flatiron Institute, 162 5th Avenue, Manhattan, NY, USA ABSTRACT We present an analysis of 1524 spectra of Vega spanning 10 years, in which we search for periodic radial velocity variations. A signal with a periodicity of 0.676 days and a semi-amplitude of ∼10 m s-1 is consistent with the rotation period measured over much shorter time spans by previous spectroscopic and spectropolari- metric studies, confirming the presence of surface features on this A0 star. The timescale of evolution of these features can provide insight into the mechanism that sustains the weak magnetic fields in normal A type stars. Modeling the radial velocities with a Gaussian process using a quasi-periodic kernel suggests that the charac- teristic spot evolution timescale is ∼180 days, though we cannot exclude the possibility that it is much longer. -
Culmination of a Constellation
Culmination of a Constellation Over any night, stars and constellations in the sky will appear to move from east to west due to the Earth’s rotation on its axis. A constellation will culminate (reach its highest point in the sky for your location) when it centres on the meridian - an imaginary line that runs across the sky from north to south and also passes through the zenith (the point high in the sky directly above your head). For example: When to Observe Constellations The taBle shows the approximate time (AEST) constellations will culminate around the middle (15th day) of each month. Constellations will culminate 2 hours earlier for each successive month. Note: add an hour to the given time when daylight saving time is in effect. The time “12” is midnight. Sunrise/sunset times are rounded off to the nearest half an hour. Sun- Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Rise 5am 5:30 6am 6am 7am 7am 7am 6:30 6am 5am 4:30 4:30 Set 7pm 6:30 6pm 5:30 5pm 5pm 5pm 5:30 6pm 6pm 6:30 7pm And 5am 3am 1am 11pm 9pm Aqr 5am 3am 1am 11pm 9pm Aql 4am 2am 12 10pm 8pm Ara 4am 2am 12 10pm 8pm Ari 5am 3am 1am 11pm 9pm Aur 10pm 8pm 4am 2am 12 Boo 3am 1am 11pm 9pm 7pm Cnc 1am 11pm 9pm 7pm 3am CVn 3am 1am 11pm 9pm 7pm CMa 11pm 9pm 7pm 3am 1am Cap 5am 3am 1am 11pm 9pm 7pm Car 2am 12 10pm 8pm 6pm Cen 4am 2am 12 10pm 8pm 6pm Cet 4am 2am 12 10pm 8pm Cha 3am 1am 11pm 9pm 7pm Col 10pm 8pm 4am 2am 12 Com 3am 1am 11pm 9pm 7pm CrA 3am 1am 11pm 9pm 7pm CrB 4am 2am 12 10pm 8pm Crv 3am 1am 11pm 9pm 7pm Cru 3am 1am 11pm 9pm 7pm Cyg 5am 3am 1am 11pm 9pm 7pm Del -
Jahresbericht 2010 Mitteilungen Der Astronomischen Gesellschaft 94 (2013), 583–627
Jahresbericht 2010 Mitteilungen der Astronomischen Gesellschaft 94 (2013), 583–627 Potsdam Leibniz-Institut für Astrophysik Potsdam (AIP) An der Sternwarte 16, D-14482 Potsdam Tel. 03317499-0, Telefax: 03317499-267 E-Mail: [email protected] WWW: http://www.aip.de Beobachtungseinrichtungen Robotisches Observatorium STELLA Observatorio del Teide, Izaña E-38205 La Laguna, Teneriffa, Spanien Tel. +34 922 329 138 bzw. 03317499-633 LOFAR-Station DE604 Potsdam-Bornim D-14469 Potsdam Tel. 03317499-291, Telefax: 03317499-352 Observatorium für Solare Radioastronomie Tremsdorf D-14552 Tremsdorf Tel. 03317499-291, Telefax: 03317499-352 Sonnenobservatorium Einsteinturm Telegrafenberg, D-14473 Potsdam Tel. 0331288-2303/-2304, Telefax: 03317499-524 0 Allgemeines Das Leibniz-Institut für Astrophysik Potsdam (AIP) ist eine Stiftung bürgerlichen Rechts zum Zweck der wissenschaftlichen Forschung auf dem Gebiet der Astrophysik. Als außer- universitäre Forschungseinrichtung ist es Mitglied der Leibniz-Gemeinschaft. Seinen For- schungsauftrag führt das AIP im Rahmen von nationalen und internationalen Kooperatio- nen aus. Die Beteiligung am Large Binocular Telescope auf dem Mt Graham in Arizona, dem größten optischen Teleskop der Welt, verdient hierbei besondere Erwähnung. Neben seinen Forschungsarbeiten profiliert sich das Institut zunehmend als Kompetenzzentrum im Bereich der Entwicklung von Forschungstechnologie. Vier gemeinsame Berufungen mit der Universität Potsdam und mehrere außerplanmäßige Professuren und Privatdozenturen an Universitäten in der Region und