Macrocosmo Nº24
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Occuttau'm@Newsteuer
Occuttau'm@Newsteuer Volume IV, Number 3 january, 1987 ISSN 0737-6766 Occultation Newsletter is published by the International Occultation Timing Association. Editor and compos- itor: H. F. DaBo11; 6N106 White Oak Lane; St. Charles, IL 60174; U.S.A. Please send editorial matters, new and renewal memberships and subscriptions, back issue requests, address changes, graze prediction requests, reimbursement requests, special requests, and other IOTA business, but not observation reports, to the above. FROM THE PUBLISHER IOTA NEWS This is the first issue of 1987. Some reductions in David Id. Dunham prices of back issues are shown below. The main purpose of this issue is to distribute pre- dictions and charts for planetary and asteroidal oc- When renewing, please give your name and address exactly as they ap- pear on your mailing label, so that we can locate your file; if the cultations that occur during at least the first part label should be revised, tell us how it should be changed. of 1987. As explained in the article about these If you wish, you may use your VISA or NsterCard for payments to IOTA; events starting on p. 41, the production of this ma- include the account number, the expiration date, and your signature. terial was delayed by successful efforts to improve Card users must pay the full prices. If paying by cash, check, or the prediction system and various year-end pres- money order, please pay only the discount prices. Full Discount sures, including the distribution o"' lunar grazing price price occultation predictions. Unfortunately, this issue IOTA membership dues (incl. -
THE STAR FORMATION NEWSLETTER an Electronic Publication Dedicated to Early Stellar Evolution and Molecular Clouds
THE STAR FORMATION NEWSLETTER An electronic publication dedicated to early stellar evolution and molecular clouds No. 90 — 27 March 2000 Editor: Bo Reipurth ([email protected]) Abstracts of recently accepted papers The Formation and Fragmentation of Primordial Molecular Clouds Tom Abel1, Greg L. Bryan2 and Michael L. Norman3,4 1 Harvard Smithsonian Center for Astrophysics, MA, 02138 Cambridge, USA 2 Massachusetts Institute of Technology, MA, 02139 Cambridge, USA 3 LCA, NCSA, University of Illinois, 61801 Urbana/Champaign, USA 4 Astronomy Department, University of Illinois, Urbana/Champaign, USA E-mail contact: [email protected] Many questions in physical cosmology regarding the thermal history of the intergalactic medium, chemical enrichment, reionization, etc. are thought to be intimately related to the nature and evolution of pregalactic structure. In particular the efficiency of primordial star formation and the primordial IMF are of special interest. We present results from high resolution three–dimensional adaptive mesh refinement simulations that follow the collapse of primordial molecular clouds and their subsequent fragmentation within a cosmologically representative volume. Comoving scales from 128 kpc down to 1 pc are followed accurately. Dark matter dynamics, hydrodynamics and all relevant chemical and radiative processes (cooling) are followed self-consistently for a cluster normalized CDM structure formation model. Primordial molecular clouds with ∼ 105 solar masses are assembled by mergers of multiple objects that have formed −4 hydrogen molecules in the gas phase with a fractional abundance of ∼< 10 . As the subclumps merge cooling lowers the temperature to ∼ 200 K in a “cold pocket” at the center of the halo. Within this cold pocket, a quasi–hydrostatically > 5 −3 contracting core with mass ∼ 200M and number densities ∼ 10 cm is found. -
Binocular Double Star Logbook
Astronomical League Binocular Double Star Club Logbook 1 Table of Contents Alpha Cassiopeiae 3 14 Canis Minoris Sh 251 (Oph) Psi 1 Piscium* F Hydrae Psi 1 & 2 Draconis* 37 Ceti Iota Cancri* 10 Σ2273 (Dra) Phi Cassiopeiae 27 Hydrae 40 & 41 Draconis* 93 (Rho) & 94 Piscium Tau 1 Hydrae 67 Ophiuchi 17 Chi Ceti 35 & 36 (Zeta) Leonis 39 Draconis 56 Andromedae 4 42 Leonis Minoris Epsilon 1 & 2 Lyrae* (U) 14 Arietis Σ1474 (Hya) Zeta 1 & 2 Lyrae* 59 Andromedae Alpha Ursae Majoris 11 Beta Lyrae* 15 Trianguli Delta Leonis Delta 1 & 2 Lyrae 33 Arietis 83 Leonis Theta Serpentis* 18 19 Tauri Tau Leonis 15 Aquilae 21 & 22 Tauri 5 93 Leonis OΣΣ178 (Aql) Eta Tauri 65 Ursae Majoris 28 Aquilae Phi Tauri 67 Ursae Majoris 12 6 (Alpha) & 8 Vul 62 Tauri 12 Comae Berenices Beta Cygni* Kappa 1 & 2 Tauri 17 Comae Berenices Epsilon Sagittae 19 Theta 1 & 2 Tauri 5 (Kappa) & 6 Draconis 54 Sagittarii 57 Persei 6 32 Camelopardalis* 16 Cygni 88 Tauri Σ1740 (Vir) 57 Aquilae Sigma 1 & 2 Tauri 79 (Zeta) & 80 Ursae Maj* 13 15 Sagittae Tau Tauri 70 Virginis Theta Sagittae 62 Eridani Iota Bootis* O1 (30 & 31) Cyg* 20 Beta Camelopardalis Σ1850 (Boo) 29 Cygni 11 & 12 Camelopardalis 7 Alpha Librae* Alpha 1 & 2 Capricorni* Delta Orionis* Delta Bootis* Beta 1 & 2 Capricorni* 42 & 45 Orionis Mu 1 & 2 Bootis* 14 75 Draconis Theta 2 Orionis* Omega 1 & 2 Scorpii Rho Capricorni Gamma Leporis* Kappa Herculis Omicron Capricorni 21 35 Camelopardalis ?? Nu Scorpii S 752 (Delphinus) 5 Lyncis 8 Nu 1 & 2 Coronae Borealis 48 Cygni Nu Geminorum Rho Ophiuchi 61 Cygni* 20 Geminorum 16 & 17 Draconis* 15 5 (Gamma) & 6 Equulei Zeta Geminorum 36 & 37 Herculis 79 Cygni h 3945 (CMa) Mu 1 & 2 Scorpii Mu Cygni 22 19 Lyncis* Zeta 1 & 2 Scorpii Epsilon Pegasi* Eta Canis Majoris 9 Σ133 (Her) Pi 1 & 2 Pegasi Δ 47 (CMa) 36 Ophiuchi* 33 Pegasi 64 & 65 Geminorum Nu 1 & 2 Draconis* 16 35 Pegasi Knt 4 (Pup) 53 Ophiuchi Delta Cephei* (U) The 28 stars with asterisks are also required for the regular AL Double Star Club. -
Sky-High 2009
Sky-High 2009 Total Solar Eclipse, 29th March 2006 The 17th annual guide to astronomical phenomena visible from Ireland during the year ahead (naked-eye, binocular and beyond) By John O’Neill and Liam Smyth Published by the Irish Astronomical Society € 5 P.O. Box 2547, Dublin 14, Ireland. e-mail: [email protected] www.irishastrosoc.org Page 1 Foreword Contents 3 Your Night Sky Primer We send greetings to all fellow astronomers and welcome them to this, the seventeenth edition of 5 Sky Diary 2009 Sky-High. 8 Phases of Moon; Sunrise and Sunset in 2009 We thank the following contributors for their 9 The Planets in 2009 articles: Patricia Carroll, John Flannery and James O’Connor. The remaining material was written by 12 Eclipses in 2009 the editors John O’Neill and Liam Smyth. The Gal- 14 Comets in 2009 lery has images and drawings by Society members. The times of sunrise etc. are from SUNRISE by J. 16 Meteors Showers in 2009 O’Neill. 17 Asteroids in 2009 We are always glad to hear what you liked, or 18 Variable Stars in 2009 what you would like to have included in Sky-High. If we have slipped up on any matter of fact, let us 19 A Brief Trip Southwards know. We can put a correction in future issues. And if you have any problem with understanding 20 Deciphering Star Names the contents or would like more information on 22 Epsilon Aurigae – a long period variable any topic, feel free to contact us at the Society e- mail address [email protected]. -
January 2015 BRAS Newsletter
January, 2015 Next Meeting: January 12th at 7PM at HRPO Artist concept of New Horizons. For more info on it and its mission to Pluto, click on the image. What's In This Issue? President's Message Astro Short: Wild Weather on WASP -43b Secretary's Summary Message From HRPO IYL and 20/20 Vision Campaign Recent BRAS Forum Entries Observing Notes by John Nagle President's Message Welcome to a new year. I can see lots to be excited about this year. First up are the Rockafeller retreat and Hodges Gardens Star Party. Go to our website for details: www.brastro.org Almost like a Christmas present from heaven, Comet Lovejoy C/2014 Q2 underwent a sudden brightening right before Christmas. Initially it was expected to be about magnitude 8 at its brightest but right after Christmas it became visible to the naked eye. At the time of this writing, it may become as bright as magnitude 4.5 or 4. As January progresses, the comet will move farther north, and higher in the sky for us. Now all we need is for these clouds to move out…. If any of you received (or bought yourself) any astronomical related goodies for Christmas and would like to show them off, bring them to the next meeting. Interesting geeky goodies qualify also, like that new drone or 3D printer. BRAS members are invited to a star party hosted by a group called the Lake Charles Free Thinkers. It will be January 24, 2015 from 3:00 PM on, at 5335 Hwy. -
About Ten Stars Orbit Eclipsing Binary XZ
About ten stars orbit eclipsing binary XZ Andromedae Lauri Jetsu Department of Physics, P.O. Box 64, FI-00014, University of Helsinki, Finland; email: lauri.jetsu@helsinki.fi June 2, 2020 Abstract A third body in an eclipsing binary system causes regular periodic changes in the observed (O) minus the computed (C) eclipse epochs. Fourth bodies have rarely been detected from the O-C data. We apply the new Discrete Chi-square Method (DCM) to the O-C data of the eclipsing binary XZ Andromedae. These data contain the periodic signatures of at least ten wide orbit stars (WOSs). Their orbital periods are between 1.6 and 91.7 years. Since no changes have been observed in the eclipses of XZ And during the past 127 years, the orbits of all these WOSs are most probably co-planar. We give detailed instructions of how the professional and the amateur astronomers can easily repeat all stages of our DCM analysis with an ordinary PC, as well as apply this method to the O-C data of other eclipsing binaries. Key words: methods: data analysis - methods: numerical - methods: statistical - binaries: eclipsing 1 Introduction 2 Data In September 2019, we retrieved the observed (O) minus the Naked eye observations of Algol’s eclipses have been recorded computed (C) primary eclipse epochs of XZ And from the into the Ancient Egyptian Calendar of Lucky and Un- Lichtenknecker-Database of the BAV. These data had lucky days (Jetsu and Porceddu, 2015; Jetsu et al., 2013; been computed from the ephemeris Porceddu et al., 2018, 2008). -
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 -
La Constelacion De Tauro
LA CONSTELACION DE TAURO Es una de las constelaciones más interesantes desde el punto de vista observacional entre las que podemos ver desde el hemisferio norte. En la zona de la bóveda celeste donde identificamos la constelación de Tauro encontramos estrellas dobles y dos bellísimos cúmulos abiertos, asi como la famosa Nebulosa del Cangrejo, objeto Messier M1. 1. Las constelaciones: una aparente imágen estelar: Desde nuestra perspectiva visual como habitantes de un pequeño planeta orbitando alrededor de una estrella en una cierta galaxia espiral, observamos, en todas las direcciones de la bóveda celeste, agrupaciones aparentes de estrellas que llamamos constelaciones. Decimos que son agrupaciones aparentes porque, realmente, no tienen que estar - de hecho no lo están en general - agrupadas físicamente. Es esta la misma situación que se nos plantea en nuestra vida cotidiana cuando observamos a lo lejos dos objetos que aparentan estar juntos, y, ante la duda de si lo están o no, nosotros nos movemos lateralmente a una distancia suficiente para observarlos desde una perspectiva lateral. Es en ese momento cuando, vistos desde otro ángulo, comprobamos si están entre sí próximos o no. Este movimiento lateral es muy sencillo de realizar en nuestros avatares de la vida cotidiana, pero es evidente que, a escala astronómica, es imposible con la tecnología existente en nuestra civilización. Es imposible para nosotros salir de la Vía Láctea, nuestra galaxia espiral, para poder observar “lateralmente” una cierta estrella doble, por ejemplo, de la que sospechamos que no es una doble física, interactuando gravitacionalmente, sino que es una doble de perspectiva. Existen métodos radiométricos, espectrométricos, etc.., que nos permiten calcular la distancia de la estrellas que observamos a simple vista, y sabemos que en general, la distancia a nosotros de astros de una misma constelación varía grandemente. -
C Curves for Contact Binaries in the Kepler Catalog
The Behavior of 0 - C Curves for Contact Binaries in the Kepler Catalog by Kathy Tran Submitted to the Department of Physics in partial fulfillment of the requirements for the degree of ARCHVES Bachelor of Science in Physics H INSTI UE /i""L HNOLOGY at the SEP 0 4 2013 MASSACHUSETTS INSTITUTE OF TECHNOLOGY :,!R)ARIES June 2013 ©Massachusetts Institute of Technology 2013. All rights reserved. Author ................. ........................ Department of Physics May 17, 2013 Certified by..... ... .. ..... ..... .S .a.. ...... ...... ...... .... Saul A. Rappaport Professor Emeritus Thesis Supervisor A ccepted by .................. .... ............................... Nergis Mavalvala Thesis Coordinator 2 The Behavior of 0 - C Curves for Contact Binaries in the Kepler Catalog by Kathy Tran Submitted to the Department of Physics on May 17, 2013, in partial fulfillment of the requirements for the degree of Bachelor of Science in Physics Abstract In this thesis, we study the timing of eclipses for contact binary systems in the Ke- pler catalog. Observed eclipse times were determined from Kepler long-cadence light curves and "observed minus calculated" (0 - C) curves were generated for both pri- mary and secondary eclipses of the contact binary systems. We found the 0 - C curves of contact binaries to be clearly distinctive from the curves of other binaries. The key characteristics of these curves are random-walk like variations, with typical semi-amplitudes of 200 to 300 seconds, quasi-periodicities, and anti-correlated behav- ior between the curves of the primary and secondary eclipses. We performed a formal analysis of systems with dominant anti-correlated behavior, calculating correlation coefficients as low as -0.77, with a mean value of -0.42. -
Download This Article in PDF Format
A&A 397, 693–710 (2003) Astronomy DOI: 10.1051/0004-6361:20021545 & c ESO 2003 Astrophysics Near-IR echelle spectroscopy of Class I protostars: Mapping Forbidden Emission-Line (FEL) regions in [FeII] C. J. Davis1,E.Whelan2,T.P.Ray2, and A. Chrysostomou3 1 Joint Astronomy Centre, 660 North A’oh¯ok¯u Place, University Park, Hilo, Hawaii 96720, USA 2 Dublin Institute for Advanced Studies, School of Cosmic Physics, 5 Merrion Square, Dublin 2, Ireland 3 Department of Physical Sciences, University of Hertfordshire, Hatfield, Herts AL10 9AB, UK Received 27 August 2002 / Accepted 22 October 2002 Abstract. Near-IR echelle spectra in [FeII] 1.644 µm emission trace Forbidden Emission Line (FEL) regions towards seven Class I HH energy sources (SVS 13, B5-IRS1, IRAS 04239+2436, L1551-IRS5, HH 34-IRS, HH 72-IRS and HH 379-IRS) and three classical T Tauri stars (AS 353A, DG Tau and RW Aur). The parameters of these FEL regions are compared to the characteristics of the Molecular Hydrogen Emission Line (MHEL) regions recently discovered towards the same outflow sources (Davis et al. 2001 – Paper I). The [FeII] and H2 lines both trace emission from the base of a large-scale collimated outflow, although they clearly trace different flow components. We find that the [FeII] is associated with higher-velocity gas than the H2, and that the [FeII] emission peaks further away from the embedded source in each system. This is probably because the [FeII] is more closely associated with HH-type shocks in the inner, on-axis jet regions, while the H2 may be excited along the boundary between the jet and the near-stationary, dense ambient medium that envelopes the protostar. -
Legacy Image
NASA SP17069 NASA Thesaurus Astronomy Vocabulary Scientific and Technical Information Division 1988 National Aeronautics and Space Administration Washington, M= . ' NASA SP-7069 NASA Thesaurus Astronomy Vocabulary A subset of the NASA Thesaurus prepared for the international Astronomical Union Conference July 27-31,1988 This publication was prepared by the NASA Scientific and Technical Information Facility operated for the National Aeronautics and Space Administration by RMS Associates. INTRODUCTION The NASA Thesaurus Astronomy Vocabulary consists of terms used by NASA indexers as descriptors for astronomy-related documents. The terms are presented in a hierarchical format derived from the 1988 edition of the NASA Thesaurus Volume 1 -Hierarchical Listing. Main (postable) terms and non- postable cross references are listed in alphabetical order. READING THE HIERARCHY Each main term is followed by a display of its context within a hierarchy. USE references, UF (used for) references, and SN (scope notes) appear immediately below the main term, followed by GS (generic structure), the hierarchical display of term relationships. The hierarchy is headed by the broadest term within that hierarchy. Terms that are broader in meaning than the main term are listed . above the main term; terms narrower in meaning are listed below the main term. The term itself is in boldface for easy identification. Finally, a list of related terms (RT) from other hierarchies is provided. Within a hierarchy, the number of dots to the left of a term indicates its hierarchical level - the more dots, the lower the level (i.e., the narrower the meaning of the term). For example, the term "ELLIPTICAL GALAXIES" which is preceded by two dots is narrower in meaning than "GALAXIES"; this in turn is narrower than "CELESTIAL BODIES". -
Meteor Activity Outlook for November 14-20, 2020
Meteor Activity Outlook for November 14-20, 2020 During this period, the moon reaches its new phase on Sunday November 15th. At this time, the moon is located near the sun and is invisible at night. As this period progresses, the waxing crescent moon will enter the evening sky but will not interfere with meteor observations, especially during the more active morning hours. The estimated total hourly meteor rates for evening observers this week is near 4 as seen from mid-northern latitudes and 3 as seen from tropical southern locations (25S). For morning observers, the estimated total hourly rates should be near 20 as seen from mid- northern latitudes (45N) and 14 as seen from tropical southern locations (25S). The actual rates will also depend on factors such as personal light and motion perception, local weather conditions, alertness, and experience in watching meteor activity. Note that the hourly rates listed below are estimates as viewed from dark sky sites away from urban light sources. Observers viewing from urban areas will see less activity as only the brighter meteors will be visible from such locations. The radiant (the area of the sky where meteors appear to shoot from) positions and rates listed below are exact for Saturday night/Sunday morning November 14/15. These positions do not change greatly day to day so the listed coordinates may be used during this entire period. Most star atlases (available at science stores and planetariums) will provide maps with grid lines of the celestial coordinates so that you may find out exactly where these positions are located in the sky.