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1903Aj 23 . . . 22K 22 the Asteojsomic Al
22 THE ASTEOJSOMIC AL JOUENAL. Nos- 531-532 22K . Taking into account the smallness of the weights in- concerned. Through the use of these tables the positions . volved, the individual differences which make up the and motions of many stars not included in the present 23 groups in the preceding table agree^very well. catalogue can be brought into systematic harmony with it, and apparently without materially less accuracy for the in- dividual stars than could be reached by special compu- Tables of Systematic Correction for N2 and A. tations for these stars in conformity with the system of B. 1903AJ The results of the foregoing comparisons. have been This is especially true of the star-places computed by utilized to form tables of systematic corrections for ISr2, An, Dr. Auwers in the catalogues, Ai and As. As will be seen Ai and As. In right-ascension no distinction is necessary by reference to the catalogue the positions and motions of between the various catalogues published by Dr. Auwers, south polar stars taken from N2 agree better with the beginning with the Fundamental-G at alo g ; but in decli- results of this investigation than do those taken from As, nation the distinction between the northern, intermediate, which, in turn, are quoted from the Cape Catalogue for and southern catalogues must be preserved, so far as is 1890. SYSTEMATIC COBEECTIOEB : CEDEE OF DECLINATIONS. Eight-Ascensions ; Cokrections, ¿las and 100z//xtf. Declinations; Corrections, Æs and IOOzZ/x^. B — ISa B —A B —N2 B —An B —Ai âas 100 â[is âas 100 âgô âSs 100 -
Redalyc.PROPER MOTIONS of L1551 IRS 5 BINARY SYSTEM
Revista Mexicana de Astronomía y Astrofísica ISSN: 0185-1101 [email protected] Instituto de Astronomía México Villa, A. M.; Trinidad, M. A.; de la Fuente, E.; Rodríguez-Esnard, T. PROPER MOTIONS OF L1551 IRS 5 BINARY SYSTEM USING 7 MM VLA OBSERVATIONS Revista Mexicana de Astronomía y Astrofísica, vol. 53, núm. 2, octubre, 2017, pp. 525- 531 Instituto de Astronomía Distrito Federal, México Available in: http://www.redalyc.org/articulo.oa?id=57153206023 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative Revista Mexicana de Astronom´ıa y Astrof´ısica, 53, 525–531 (2017) PROPER MOTIONS OF L1551 IRS 5 BINARY SYSTEM USING 7 MM VLA OBSERVATIONS A. M. Villa1, M. A. Trinidad1, E. de la Fuente2, and T. Rodr´ıguez-Esnard2 Received May 22 2017; accepted August 14 2017 ABSTRACT We analyzed high angular resolution observations of the Very Large Array archive at a wavelength of 7 mm made for the L1551 IRS 5 binary system. Six sets of observations, five with the A configuration and one with the B configura- tion, were used, covering a time span of about 15 years. With these multi-epoch data, we estimated the absolute and relative proper motions of the binary system, which are about 25.1 mas yr−1 (≈ 16.7 km s−1 considering a distance of 140 pc) and 4.2 mas yr−1, respectively. Finally, based on the relative proper motion, we estimated a total mass for the L1551 IRS 5 binary system of 1.7 M⊙ and an orbital period of 246 years. -
Index of Occultation Newsletter (ON) 1998-2009
Index of Occultation Newsletter (ON) 1998-2009 http://www.iota-es.de/on_heritage.html Title Author Category Subject Object Volume No Page Aldebaran Graze 1998 Feb 5 Cover Profile, Chords Aldebaran, Moon 7 1 1 ESOP XVII Edwin Goffin Meeting 7 1 4 Attention Eclipse Enthusiasts Bryan Brewer Member Info Eclipse Sun 7 1 4 Good GPS Position Measurements in "Stand Alone" Mode Wolfgang Rothe Technical GPS 7 1 4 Preliminary Results of PHEMU97: A Joint Effort H. J. J. Bulder Results PHEMU, Mutual Events Jupiter, Ganymede, Io, Europa, 7 1 12 Callisto Disscussion of Timing Accuracies from TV and Other Sources Tom Harmon Technical Timing 7 1 15 Remote Video Stations Tom Campell Technical Remote Observing 7 1 16 Sun Moon Regulus 1998 August 22 Cover Sun, Moon, Regulus 7 2 1 IOTA 1998 Annual Meeting David Dunham Meeting Business Meeting 7 2 4 IOTA 1998 Annual Meeting Registration Form Meeting Business Meeting 7 2 5 IOTA Annual Meeting Lecture Proposal Form Meeting Business Meeting 7 2 6 Grazing Occultation Observations Mitsuru Soma Results Graze 7 2 7 Reports of Asteroidal Occultations in 1995 Jim Stamm Results Asteroids (654) Zelinda, (105) Artemis, 7 2 8 (106) Dione, (30) Urania, (7) Iris, (704) Interamnia, (85) Io Treasurer's Report Terri A. McManus Member Info Business Meeting 7 2 8 Tables Asteroid Occultations in 1995 Jim Stamm Results Asteroids (654) Zelinda, (30) Urania, (85) 7 2 9 Io Sad Nemws: Joaquim Soares Gracia Dies Nuno Gracias In Memoriam 7 2 10 Updates and Corrections Graze Aldebaran, Moon 7 2 10 IOTA Occultation Camera Production Scedule -
NCRAL Northern Lights Winter 2021
who have earned pins and certificates galore. Nothing seems INSIDE THIS ISSUE OF Northern Lights to keep these intrepid observers down. Would that all other astronomy clubs had such active members when it comes to NCRAL Chair’s Message…..............................……………………1 observing! (Perhaps there are, but they aren’t telling!) NCRAL Financial Statement Autumn 2020………………….……2 Looking Ahead to 2021 NCRAL 2021 May 7-8……………………..………………………..………2 Call for 2021 NCRAL Nominations & Applications……….......3 NCRAL 2021 is scheduled for Friday/Saturday, May 7-8, NCRAL Seasonal Messier Marathon Awards…………….………5 and I’m looking forward to it. I hope you are too. The Noteworthy!……………………………………………………………………6 convention will be hosted by the Neville Public Museum Profiles in Amateur Astronomy: Alan Sheidler (PAC)…..……7 Astronomical Society in De Pere, Wisconsin, just south of Club Leadership for Our Time by Carl J. Wenning………...……8 Green Bay assuming the pandemic doesn’t interfere as it did Radio Astronomy by Tim Stone…………………………….……..…10 last spring. I’m already making plans to attend NCRAL 2021 2021 Rising and Setting Charts by Jeffrey L. Hunt……….….14 and hope you are doing the same. Later in this newsletter Astronomical League 75th Anniversary Coming……..…….…17 you’ll find information about speakers, activities, and Mars 2021: Until Conjunction by Jeffrey L. Hunt.………..….18 facilities. Get this event into your calendar now so you can Future NCRAL Conventions…………………………………..……….22 avoid a schedule conflict. Seasonal Messier Mini Marathon Observing Program……22 Don’t forget to think about nominations for Regional Add Your Email Address to NCRAL Member Database…...23 officers. This year we need to elect Chair and Vice Chair to NCRAL Website………………………………………………………….….23 two-year terms and vote for a Secretary-Treasurer to Regional Officer & Leader Contact Information………..……24 complete the second year of a two-year term that began in May 2020. -
The X-Ray Puzzle of the L1551 IRS 5 Jet
A&A 530, A123 (2011) Astronomy DOI: 10.1051/0004-6361/201016305 & c ESO 2011 Astrophysics The X-ray puzzle of the L1551 IRS 5 jet P. C. Schneider1, H. M. Günther2, and J. H. M. M. Schmitt1 1 Hamburger Sternwarte, Gojenbergsweg 112, 21029 Hamburg, Germany e-mail: [cschneider;jschmitt]@hs.uni-hamburg.de 2 Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA, USA e-mail: [email protected] Received 13 December 2010 / Accepted 18 April 2011 ABSTRACT Protostars are actively accreting matter and they drive spectacular, dynamic outflows, which evolve on timescales of years. X-ray emission from these jets has been detected only in a few cases and little is known about its time evolution. We present a new Chandra observation of L1551 IRS 5’s jet in the context of all available X-ray data of this object. Specifically, we perform a spatially resolved spectral analysis of the X-ray emission and find that (a) the total X-ray luminosity is constant over almost one decade, (b) the majority of the X-rays appear to be always located close to the driving source, (c) there is a clear trend in the photon energy as a function of the distance to the driving source indicating that the plasma is cooler at larger distances and (d) the X-ray emission is located in a small volume which is unresolved perpendicular to the jet axis by Chandra. A comparison of our X-ray data of the L1551 IRS 5 jet both with models as well as X-ray observations of other protostellar jets shows that a base/standing shock is a likely and plausible explanation for the apparent constancy of the observed X-ray emission. -
Low Mass Star Formation in the Taurus-Auriga Clouds
Handbook of Star Forming Regions Vol. I Astronomical Society of the Pacific, 2008 Bo Reipurth, ed. Low Mass Star Formation in the Taurus-Auriga Clouds Scott J. Kenyon Smithsonian Astrophysical Observatory, 60 Garden Street Cambridge, MA 02138, USA Mercedes Gomez´ Observatorio Astronomico,´ Universidad Nacional de Cor´ doba Laprida 854, 5000 Cor´ doba, Argentina Barbara A. Whitney Space Science Institute, 4750 Walnut Street, Suite 205 Boulder, CO 80301, USA Abstract. We review the history and structure of star formation in the Taurus-Auriga dark clouds. Our discussion includes a summary of the macroscopic cloud properties, the population of single and binary pre-main sequence stars, the properties of jets and outflows, and detailed summaries of selected individual objects. We include compre- hensive tables of dark clouds, young stars, and jets in the clouds. 1. Overview In October 1852, J. R. Hind `noticed a very small nebulous looking object' roughly 1800 west of a tenth magnitude star in Taurus. Over the next 15 years, the nebula slowly faded in brightness and in 1868 vanished completely from the view of the largest tele- scopes. O. Struve then found a new, smaller and fainter, nebulosity roughly 40 west of Hind's nebula. While trying to recover these nebulae, Burnham (1890, 1894) discov- ered a small elliptical nebula surrounding T Tau (Figure 1). Spectra of Hind's nebula revealed emission from either Hβ or [O III] λ5007, demonstrating that the nebula was gaseous as in novae and planetary nebulae. At about the same time, Knott (1891) reported 4 magnitude variability in the `ruddy' star associated with these nebulae, T Tauri. -
Macrocosmo .Com Ano I - Edição N° 9 - Agosto De 2004 Revista Macrocosmo .Comi Ano I - Edição N° 9 - Agosto De 2004 Editorial
A PRIMEIRA REVISTA ELETRÔNICA BRASILEIRA EXCLUSIVA DE ASTRONOMIA macroCOSMO .com Ano I - Edição n° 9 - Agosto de 2004 revista macroCOSMO .comi Ano I - Edição n° 9 - Agosto de 2004 Editorial Redação Desde os primórdios da civilização, o Sol sempre [email protected] esteve presente nas religiões antigas, sendo cultuado por diferentes culturas. Disseminador das trevas, o Sol Diretor Editor Chefe foi considerado uma divindade poderosa pelos povos Hemerson Brandão da Mesopotâmia e Egito, capaz de produzir enormes [email protected] secas, mas também produtor do desenvolvimento das Revisão plantas e de todos os seres vivos da Terra. Povos como Gil Magno Cruz os toltecas realizavam sacrifícios humanos em honra ao [email protected] Deus Sol, chegando a travar grandes guerras com o Roberta Maia único propósito de capturar vítimas para seus rituais. [email protected] Tal culto durante toda a história, não poderia ser WebMaster infundado. Nossa estrela mais próxima é fonte de luz e Hemerson Brandão calor e responsável pela vida em nosso planeta. A [email protected] energia transmitida pelo Sol é de vital importância para Diagramadores a manutenção da temperatura na Terra, o ciclo da água Hemerson Brandão e da fotossíntese das plantas. Daí vêm a importância de [email protected] procurarmos entender como funciona essa gigante Rodolfo Saccani fornalha que é o nosso Sol. Pesquisas realizadas pelo [email protected] Sharon Camargo Professor Sabatino Sofia, da Yale University, tem [email protected] tentado demonstrar como as variações do Sol poderiam afetar o clima futuro em nosso planeta. Redatores Um fenômeno que está intimamente ligado às Audemário Prazeres [email protected] variações do Sol, são as manchas vermelhas. -
NCRAL Northern Lights Summer 2019
leaders, the leadership is to be highly comMended because INSIDE THIS ISSUE OF Northern Lights they have done precisely that. NCRAL Chair’s Message……………..................................……………1 Another contribution PAC has Made to NCRAL is Terry NCRAL 2019 in Review……………………………………………………………..2 Dufek’s work on the new NCRAL logo and Masthead Making NCRAL Awards & Grants…………………………………………………………..4 their appearance for the first tiMe in this issue of Northern Convention Collage………………………………………………………………….6 Lights. A higher resolution version of the new official logo will Minutes of the May 4 Regional Council & Business Meetings……7 be available for use on club newsletters, clothing, conference Treasurer’s Report…………………………………………………….…………….8 proceedings and so forth. See later in this newsletter issue. NCRAL Logo Contest Winner…………………………………….……………..9 During this year’s Regional business Meeting, the Official NCRAL Logo Approved by Regional Council…………………10 asseMbled MeMbers agreed to moving ahead with the Other Recent Actions by NCRAL Regional Council……………..……11 creation of four seasonal NCRAL Mini Messier Marathon 2019 NCRAL MeMbership RecruitMent Mini Grant………………...11 certificates and pins. The Astronomical League has no such Abridged NCRAL Region Report………………………………………..……12 seasonal observing program, and we will be among the first Come Walk with Me, an award-winning poeM by Jean Napp….13 to formalize such a prograM. I will be working with the NCRAL SoMe AstronoMical Heroes…………………………………………………...15 Regional Council to establish rules for this event. This will Venus as an Evening Star, 2019-2020………………………..……………17 pretty Much be a “check off list.” Required observations and Add Your Email Address to the NCRAL MeMber Database……...25 records will not qualify coMpleters for the AL Messier Call for 2020 NCRAL NoMinations…………………………………….…..25 Future NCRAL Regional Conventions……………………..…………..….27 Observing PrograM which has its own rules and regulations. -
Aas Ci 144 Gennaio 2011
ASSOCIAZIONE ASTROFILI SEGUSINI 10059 SUSA (TO) Circolare interna n. 144 Gennaio 2011 ________________________________________________________________________________ 4 GENNAIO 2011: ECLISSE PARZIALE DI SOLE Ore 09:44, fotocamera Panasonic DMC-FZ28, focale 290 mm, F/8, 100 ISO, posa 1/1000 s (r.p.) Ore 10:09, fotocamera Nikon D70, focale 70 mm, F/5, 200 ISO, posa 1/8000 s (particolare) (a.a.) La mattina del 4 gennaio (v. Circolare interna n. 143, dicembre 2010, p. 1 e Nova n. 167, 3 gennaio 2011) è avvenuta un’eclisse parziale di Sole, visibile in Europa, Nord-Africa e parte dell’Asia. Per gran parte della Valsusa, purtroppo, le condizioni meteorologiche ne hanno impedito l’osservazione. Riportiamo alcuni brevi resoconti e foto. Le ore indicate sono in CET ( Central European Time , Ora dell'Europa centrale , corrispondente all’ora solare italiana). Ferrera - Moncenisio. – Abbiamo osservato parte dell’eclisse parziale di Sole dalla Strada statale 25 del Moncenisio, in corrispondenza del bivio per Ferrera (Latitudine 45° 10’ 49” N, Longitudine 06° 59’44” E, a 1320 m slm) in una giornata fredda e nuvolosa. La temperatura era di -5°C. Una breve schiarita, a tratti, del cielo ha permesso l’osservazione del fenomeno da poco dopo la fase massima fin quasi al termine. Sono state scattate alcune foto che presentiamo in queste pagine; quella in alto a pagina precedente è stata anche pubblicata, in prima pagina, dal settimanale locale “ La Valsusa ” (anno 115, n. 1, 6 gennaio 2011). (r.p.-al.a.) Il Sole alle ore 10:09 Un’immagine della strada da cui è stata effettuata l’osservazione e le nubi davanti al Rocciamelone. -
NCRAL Northern Lights Spring 2020
requests to the membership. This will allow Northern INSIDE THIS ISSUE OF Northern Lights Cross to take advantage of all the hard work they had NCRAL Chair’s Message……………..................................……………1 already put in to develop NCRAL VISION 2020. NCRAL VISION 2020 Canceled…………………………………………………2 2. We need to appoint a Region member to serve as NCRAL Chair’s Report………………….….……………………….…….………..3 Representative to the Astronomical League as I failed to NCRAL Financial Statement………………………………..…….………..……3 include this election last year during the business NCRAL Financial Statement……………………………………………………..3 meeting. Vice-Chair Bill Davidson was appointed then to Call for 2020 NCRAL Nominations……………………………….……….…..4 fill the position temporarily. We will not be holding a Updates to NCRAL Awards Programs..................………………………5 Regional business meeting this year. As Regional Chair I Future NCRAL Conventions………………….………………..………..…..….6 have made the decision reappoint Vice Chair Bill NCRAL Seasonal Messier Marathon Awards – Winter 2020……...6 Davidson to continue in the job of Regional Noteworthy!……………………………………………………………………………6 Representative to the Astronomical League to complete News Notes…………………………………………………………………………….7 the remainder of the original three-year term. He has NCRAL Seasonal Messier Marathon Observing Program…………..9 agreed to this appointment. Add Your Email Address to NCRAL Member Database…………..10 3. Because I don’t want the Coronavirus to completely Jupiter and Saturn in 2020: Review April-June………………………11 disrupt the activities of our North Central Region, NCRAL Website………………………………………………………………….….12 following consultation with our elected leaders I have as Regional Officer & Leader Contact Information………………………13 Regional Chair decided that we will continue with the 2020 awards programs. Award nomination and grant NCRAL CHAIR’S MESSAGE application deadlines remain fixed as March 31st. -
April 2019 OBSERVER
THE OBSERVER OF THE TWIN CITY AMATEUR ASTRONOMERS Volume 44, Number 4 April 2019 INSIDE THIS ISSUE: A WORD FROM NCRAL CHAIR CARL WENNING « 1 A Word from NCRAL Chair Carl Wenning For the first time since I have served as editor of this newsletter « 2 President’s Note (beginning in 2013), I do not have an Image of the Month to share. « 3 Calendar of Celestial Events – April 2019 This is not for a want of trying by our astrophotographers. The sky « 3 New & Renewing Members/Dues Blues/E-Mail List this winter and spring has been almost entirely overcast. Yes, there « 4 This Month’s Phases of the Moon have been a few pictures, but not of the sort we have become « 4 This Month’s Solar Phenomena accustomed to seeing on the cover of this publication. So, I’m « 5 AstroBits – News from Around the TCAA taking this opportunity as Chair of the North Central Region of the « 7 TCAA Image Gallery Astronomical League (NCRAL) to say a few words about this « 8 April 2019 with Jeffrey L. Hunt organization with which the TCAA is affiliated. « 13 Public Viewing Sessions Schedule for 2019 First and foremost, I want to point out the NCRAL annual « 13 TCAA Active on Facebook convention will soon be hosted by our friends in Moline, IL – the « 14 TCAA Calendar of Events for 2019 Popular Astronomy Club. This group has done a fantastic job « 14 TCAA Treasurer’s Report as of March 29, 2019 preparing NCRAL 2019 and I hope you will attend. -
The Annual Guide to the Wonders of the Night Sky Visible from Ireland During the Year Ahead 12Th Year of Publication by Liam Smyth and John Flannery
5 The annual guide to the wonders of the night sky visible from Ireland during the year ahead 12th year of publication by Liam Smyth and John Flannery monthly phenomena ... the year in review ... naked-eye comets in 2004 ... space missions ... detailed notes on celestial highlights ... the June 8th transit of Venus ... and lots more Published by the Irish Astronomical Society, P.O. Box 2547, Dublin 14 — (01) 455 7801 (evenings only) we’re also on the Web and e-mail — www.esatclear.ie/~ias or [email protected] page 1 REETINGS to all fellow astronomers and wel- It is fair to say that those with even just a casual interest in Gcome to the twelfth annual edition of Sky-High. the night sky should find a year of fascinating reading within Each year we lead with a general introduction to help set the pages of Sky-High 2004. That is not to say we have cov- the scene for those new to the hobby. We ask the indul- ered all phenomena visible as this guide is generally pitched gence of established readers in this regard. toward naked eye and binocular observers. A subscription to a We have carried out an expansion of the content this monthly astronomy magazine though will keep you up-to-date year to provide more comprehensive notes on particular on transient phenomena such as comets or novae, as well as phenomena. This has allowed us to cater for the budding supplying more detailed data on solar system objects. sky watcher taking their first steps in the hobby while giv- As always, feel free to contact us through the IAS with ing a sufficient level of detail to satisfy the more serious your comments or for further information on any of the sights amateur astronomer.