DOCSLIB.ORG

SEPTEMBER 2012 SEPTEMBER 2012 OT H E D Ebn V E R S E R V E R

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
SEPTEMBER 2012 SEPTEMBER 2012 OT H E D Ebn V E R S E R V E R THE DENVER OBSERVER SEPTEMBER 2012 SEPTEMBER 2012 OT h e D eBn v e r S E R V E R S A I L S A L O F T F O R A M I L K Y WAY V O Y A G E ! RHO OPHIUCHI REGION Calendar Several different types of nebulosity are distinct in this image. The yellowish cloud associated with Antares (the brightest star in the image), is IC 4606. Above Antares is IC 4605 which is the blue reflection nebula 8.............................. Last quarter moon around 22 Scorpii. To the left of 22 Scorpii is the dark nebula B44. IC 4604 is the blue nebulosity around Rho Ophiuchi, the triple star above that. Below Rho Ophiuchi is the blue nebulosity of IC 4603. Sh 2-9 is the red 15........................................ New moon emission nebula associated with Sigma Scorpii, the blue star near the right edge of the image. Below Sigma Scorpii and to the right of Antares is the globular cluster M4. To the upper right of Antares is the smaller 22........................... First quarter moon globular cluster NGC 6144. This image is comprised of a four images mosaic. It was shot with a Mamiya 29........................................ Full moon lens with HaLRGB filters, binned 1x1 with an SBIG ST-2000XM CCD camera. Image © Joe Gafford Inside the Observer SEPTEMBER SKIES by Dennis Cochran he Age of Aquarius is upon us. This sprawling with all of its well-known nebulae and star clusters President’s Corner.......................... 2 T constellation reaches out over Capricornus from above the teapot shape of his bow-and-arrow body northeast of its “grin” and manages to cover an that we talked about in “July Skies.” That’s his arrow Society Directory............................ 2 impressive chunk of sky. The Water-Bearer (Aquarius) pointed west towards Antares, the big red star called Schedule of Events.......................... 2 harbors the large globular cluster M2 right on the me- the “Heart of the Scorpion.” ridian below its famous sister M15. Bag ‘em both! M15 is In the empty space between Sagittarius and Capri- DAS Job Jar................................... 4 just up-left from tiny Equuleus, itself just down-left cornus are two interesting objects near to one another: from the easier-to-spot asterism Delphinus the Dol- dwarf galaxy NGC 6822 and a planetary known as the September Speaker......................... 4 phin. Once you’ve found M15, M2 is halfway down to “Little Gem,” NGC 6818. They are straight west of the Adopt a Telescope Project................. 5 Capricornus. Although western Sagittarius has the western corner of Capricornus and straight east of the Saturn Nebula, a planetary that looks like it has a fat end of that little string of stars that projects northeast DAS Bioblitz Project....................... 6 ring, it’s located just above the middle of the goat’s wide from ς (sigma) Sgr, the uppermost star in the handle of grinning “V.” The cluster M73 is just down-right from the teapot. Beginners Bits................................ 7 the planetary, the second-brightest in the sky, and Low to the southern horizon there are several ob- next to globular cluster M72, so this area is worth New members.................... back page jects squished in the space between Scorpius and Sagit- checking out. Meanwhile west of mid-south, Sagitta- tarius. Above and above-left of the “Cat’s Eyes” pair of M27.................................. back page rius continues to dominate the southern evening sky Continued on Page 3 The Denver Astronomical Society One Mile Nearer the Stars Page 1 THE DENVER OBSERVER SEPTEMBER 2012 PRESIDENT’S CORNER by Ron Pearson Society Directory ugust was another tough summer month for One of the major goals or missions of DAS is out- President: A DAS members. Instead of observing the glitter- reach to schools and others in the science of astron- Ron Pearson (303) 670-1299 ing Milky Way, we had unrelenting wild fire haze omy and science in general since astronomy literally [email protected] obscuring the night sky and rainless monsoon clouds encompasses the whole Universe in its sphere of Vice President: Lisa Judd (626) 487-8515 making even just one night of observing more re- study. We conduct our outreach efforts through both [email protected] warding. I got out for the Perseid Meteor shower and Chamberlin Observatory Public Nights and Open Secretary: saw 15 or so meteors in an hour and half before Houses with teams of telescope operators and our Dennis Cochran (720) 870-0465 clouds closed in again. On the August new moon school or outside outreach programs through a cadre Treasurer: Brad Gilman (720) 488-1028 weekend we got a brief respite from the photonic made up of you, our members, who volunteer ad hoc assault coming out of the oil hole drilling near our to requests as we receive them. Both of these pro- dark sky site. But, don’t celebrate too much, because grams rely on you, our members, to volunteer and Executive Board Members the assault on our night sky and night vision may contribute your time and talents. We have recently resume at any time this fall. According to informa- welcomed several newly certified operators of the Chuck Carlson Ron Hranac tion posted on the Southwestern Energy and CO. Oil historic 20-inch Clark telescope to help out in the Jack Eastman Naomi Pequette & Gas Conservation Commission websites, despite dome room, and we welcome those who have Joe Gafford David Shouldice mediocre returns on their initial tests, they will be stepped up recently to take leadership roles in both Chuck Habenicht Dan Wray extending the depth of the drilling near our site over Chamberlin and our outside programs. Scott Leach is President Emeritus, Larry Brooks 4,000 feet horizontally, and intend to drill a second newly certified operator and will also be our IT sup- hole “in the area” before the end of the year. As ama- port lead. He replaces Chadd Warwick whose job teurs, professionals and others interested in the sci- keeps him in out of state. Scott will be leading im- Committees ence up in our night sky it is ironic that we are so provements to our AV computer network in Cham- directly confronted and impacted by the effects of berlin which we use to present talks and images from Van Nattan-Hansen Scholarship Fund: two other major issues in science and our society; our telescope camera, as well as provide internet Tim Pimental (Chair) PO Box 100621 greenhouse-driven global warming that is contribut- access and the PN reservation system. Amanda Parry Denver, CO. 80250-0621 ing to the spread of wild fires and drought while the has been our outreach coordinator for the past three EGK Dark Site Committee: search for carbon-releasing fossil fuel goes on in ear- months and Justin Modra will be taking the lead in Darrell Dodge, Interim Chair nest, literally in our faces. It certainly proves what we one aspect of our outreach education—the area of Email: [email protected] IDA Representative: learned in school; John Donne light pollution education. Perhaps you have seen or Dr. Robert Stencel said, that “No Man is an read about the excellent documentary film about Email: [email protected] Island. ” and “. never light pollution called The City Dark. With Justin’s send to know for whom proposal, the e-board approved the purchase of a full the bell tolls; It tolls for licensed version of the documentary, and Justin will Volunteers or Appointed Representatives thee.”* These issues also be lining up venues to show the film. point to an ever- increasing What this society does and accomplishes either at need for science education its dark sky site, or in the areas of astronomy out- ALCor: in schools as our schools get reach at Chamberlin or in school yards, or battling Darrell Dodge (303) 932-1309 Newsletter: back into session. Continued on Page 4 Editor: Patti Kurtz (720) 217-5707 Email: [email protected] The Observer is available in color PDF DAS SCHEDULE format from the DAS website. Website: SEPTEMBER OCTOBER Darrell Dodge Email: [email protected] 3 Labor Day 5 E-Board Meeting at Chamberlin (Be- IT Coordinator: Scott Leach 7 E-Board Meeting at Chamberlin (Be- gins at 7:30 P.M.) gins at 7:30 P.M.) 12-14 EGK Dark Sky weekend Librarian: 8-16 Okie-Tex Starparty 20 Colorado Astronomy Day at DMNS Phil Klos 14-16 EGK Dark Sky weekend and Chamberlin Observatory (10 A.M. DAS Information Line:(303) 871-5172 22 Open House at Chamberlin Observa- to 4 P.M.) and Open House (Begins at DAS Correspondence: Denver Astronomical Society tory (Begins at 7:00 P.M.) 6:00 P.M.) Chamberlin Observatory c/o Ron Pearson 26 Yom Kippur 27 DAS Auction at Chamberlin Observa- 2930 East Warren Avenue 28 DAS General Membership meeting at tory (Setup begins at 11:00 A.M., Bidding Denver, Colorado 80210 D.U.’s Olin Hall: Speaker: Peg Alig — begins at 1:00 P.M.) “Baehr Observatory in Pine, CO.” (Be- 31 Hallowe’en gins at 7:30 P.M.) The Executive Board conducts the business of the DAS at 7:30 p.m. at Chamberlin Observatory. Public nights are held at Chamberlin Observatory every Tuesday and Thursday evenings Please see the Schedule of Events for meeting beginning at the fo$owing times: dates. A% members are welcome. March 13 - April 14 at 8:00 P.M. April 15 - August 31 at 8:30 P.M. September 1 - September 30 at 8:00 P.M. October 1 - March 10 at 7:00 P.M. Costs to non-members are: $3.00 adults, $2.00 children www.denverastro.org Please make reservations via our website )www.denverastro.org) or ca$ )303) 871-5172.
Load more

Recommended publications
  • An Intriguing Globular Cluster in the Galactic Bulge from the VVV Survey ? D
    Astronomy & Astrophysics manuscript no. minni48_vf5 ©ESO 2021 June 29, 2021 An Intriguing Globular Cluster in the Galactic Bulge from the VVV Survey ? D. Minniti1; 2, T. Palma3, D. Camargo4, M. Chijani-Saballa1, J. Alonso-García5; 6, J. J. Clariá3, B. Dias7, M. Gómez1, J. B. Pullen1, and R. K. Saito8 1 Departamento de Ciencias Físicas, Facultad de Ciencias Exactas, Universidad Andres Bello, Fernández Concha 700, Las Condes, Santiago, Chile 2 Vatican Observatory, Vatican City State, V-00120, Italy 3 Observatorio Astronómico, Universidad Nacional de Córdoba, Laprida 854, 5000 Córdoba, Argentina 4 Colégio Militar de Porto Alegre, Ministério da Defesa, Av. José Bonifácio 363, Porto Alegre, 90040-130, RS, Brazil 5 Centro de Astronomía (CITEVA), Universidad de Antofagasta, Av. Angamos 601, Antofagasta, Chile 6 Millennium Institute of Astrophysics, Nuncio Monseñor Sotero Sanz 100, Of. 104, Providencia, Santiago, Chile 7 Instituto de Alta Investigación, Sede Iquique, Universidad de Tarapacá, Av. Luis Emilio Recabarren 2477, Iquique, Chile 8 Departamento de Física, Universidade Federal de Santa Catarina, Trindade 88040-900, Florianópolis, SC, Brazil Received ; Accepted ABSTRACT Context. Globular clusters (GCs) are the oldest objects known in the Milky Way so each discovery of a new GC is astrophysically important. In the inner Galactic bulge regions these objects are difficult to find due to extreme crowding and extinction. However, recent near-IR Surveys have discovered a number of new bulge GC candidates that need to be further investigated. Aims. Our main objective is to use public data from the Gaia Mission, the VISTA Variables in the Via Lactea Survey (VVV), the Two Micron All Sky Survey (2MASS), and the Wide-field Infrared Survey Explorer (WISE) in order to measure the physical parameters of Minni 48, a new candidate globular star cluster located in the inner bulge of the Milky Way at l = 359:35 deg, b = 2:79 deg.
    [Show full text]
  • KELT-14B and KELT-15B: an Independent Discovery of WASP-122B and a New Hot Jupiter
    Swarthmore College Works Physics & Astronomy Faculty Works Physics & Astronomy 5-11-2016 KELT-14b And KELT-15b: An Independent Discovery Of WASP-122b And A New Hot Jupiter J. E. Rodriguez K. D. Colón K. G. Stassun D. Wright P. A. Cargile See next page for additional authors Follow this and additional works at: https://works.swarthmore.edu/fac-physics Part of the Astrophysics and Astronomy Commons Let us know how access to these works benefits ouy Recommended Citation J. E. Rodriguez, K. D. Colón, K. G. Stassun, D. Wright, P. A. Cargile, D. Bayliss, J. Pepper, K. A. Collins, R. B. Kuhn, M. B. Lund, R. J. Siverd, G. Zhou, B. S. Gaudi, C. G. Tinney, K. Penev, T. G. Tan, C. Stockdale, I. A. Curtis, D. James, S. Udry, D. Segransan, A. Bieryla, D. W. Latham, T. G. Beatty, J. D. Eastman, G. Myers, J. Bartz, J. Bento, Eric L.N. Jensen, T. E. Oberst, and D. J. Stevens. (2016). "KELT-14b And KELT-15b: An Independent Discovery Of WASP-122b And A New Hot Jupiter". Astronomical Journal. Volume 151, Issue 6. 138 DOI: 10.3847/0004-6256/151/6/138 https://works.swarthmore.edu/fac-physics/286 This work is brought to you for free by Swarthmore College Libraries' Works. It has been accepted for inclusion in Physics & Astronomy Faculty Works by an authorized administrator of Works. For more information, please contact [email protected]. Authors J. E. Rodriguez, K. D. Colón, K. G. Stassun, D. Wright, P. A. Cargile, D. Bayliss, J. Pepper, K. A. Collins, R.
    [Show full text]
  • Durham E-Theses
    Durham E-Theses First visibility of the lunar crescent and other problems in historical astronomy. Fatoohi, Louay J. How to cite: Fatoohi, Louay J. (1998) First visibility of the lunar crescent and other problems in historical astronomy., Durham theses, Durham University. Available at Durham E-Theses Online: http://etheses.dur.ac.uk/996/ Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in Durham E-Theses • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full Durham E-Theses policy for further details. Academic Support Oce, Durham University, University Oce, Old Elvet, Durham DH1 3HP e-mail: [email protected] Tel: +44 0191 334 6107 http://etheses.dur.ac.uk me91 In the name of Allah, the Gracious, the Merciful >° 9 43'' 0' eji e' e e> igo4 U61 J CO J: lic 6..ý v Lo ý , ý.,, "ý J ýs ýºý. ur ý,r11 Lýi is' ý9r ZU LZJE rju No disaster can befall on the earth or in your souls but it is in a book before We bring it into being; that is easy for Allah. In order that you may not grieve for what has escaped you, nor be exultant at what He has given you; and Allah does not love any prideful boaster.
    [Show full text]
  • Messier Plus Marathon Text
    Messier Plus Marathon Object List by Wally Brown & Bob Buckner with additional objects by Mike Roos Object Data - Saguaro Astronomy Club Score is most numbered objects in a single night. Tiebreaker is count of un-numbered objects Observer Name Date Address Marathon Obects __________ Tiebreaker Objects ________ SEQ OBJECT TYPE CON R.A. DEC. RISE TRANSIT SET MAG SIZE NOTES TIME M 53 GLOCL COM 1312.9 +1810 7:21 14:17 21:12 7.7 13.0' NGC 5024, !B,vC,iR,vvmbM,st 12.. NGC 5272, !!,eB,vL,vsmbM,st 11.., Lord Rosse-sev dark 1 M 3 GLOCL CVN 1342.2 +2822 7:11 14:46 22:20 6.3 18.0' marks within 5' of center 2 M 5 GLOCL SER 1518.5 +0205 10:17 16:22 22:27 5.7 23.0' NGC 5904, !!,vB,L,eCM,eRi, st mags 11...;superb cluster M 94 GALXY CVN 1250.9 +4107 5:12 13:55 22:37 8.1 14.4'x12.1' NGC 4736, vB,L,iR,vsvmbM,BN,r NGC 6121, Cl,8 or 10 B* in line,rrr, Look for central bar M 4 GLOCL SCO 1623.6 -2631 12:56 17:27 21:58 5.4 36.0' structure M 80 GLOCL SCO 1617.0 -2258 12:36 17:21 22:06 7.3 10.0' NGC 6093, st 14..., Extremely rich and compressed M 62 GLOCL OPH 1701.2 -3006 13:49 18:05 22:21 6.4 15.0' NGC 6266, vB,L,gmbM,rrr, Asymmetrical M 19 GLOCL OPH 1702.6 -2615 13:34 18:06 22:38 6.8 17.0' NGC 6273, vB,L,R,vCM,rrr, One of the most oblate GC 3 M 107 GLOCL OPH 1632.5 -1303 12:17 17:36 22:55 7.8 13.0' NGC 6171, L,vRi,vmC,R,rrr, H VI 40 M 106 GALXY CVN 1218.9 +4718 3:46 13:23 22:59 8.3 18.6'x7.2' NGC 4258, !,vB,vL,vmE0,sbMBN, H V 43 M 63 GALXY CVN 1315.8 +4201 5:31 14:19 23:08 8.5 12.6'x7.2' NGC 5055, BN, vsvB stell.
    [Show full text]
  • A Near-Infrared Photometric Survey of Metal-Poor Inner Spheroid Globular Clusters and Nearby Bulge Fields
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CERN Document Server A Near-Infrared Photometric Survey of Metal-Poor Inner Spheroid Globular Clusters and Nearby Bulge Fields T. J. Davidge 1 Canadian Gemini Office, Herzberg Institute of Astrophysics, National Research Council of Canada, 5071 W. Saanich Road, Victoria, B. C. Canada V8X 4M6 email:[email protected] ABSTRACT Images recorded through J; H; K; 2:2µm continuum, and CO filters have been obtained of a sample of metal-poor ([Fe/H] 1:3) globular clusters ≤− in the inner spheroid of the Galaxy. The shape and color of the upper giant branch on the (K; J K) color-magnitude diagram (CMD), combined with − the K brightness of the giant branch tip, are used to estimate the metallicity, reddening, and distance of each cluster. CO indices are used to identify bulge stars, which will bias metallicity and distance estimates if not culled from the data. The distances and reddenings derived from these data are consistent with published values, although there are exceptions. The reddening-corrected distance modulus of the Galactic Center, based on the Carney et al. (1992, ApJ, 386, 663) HB brightness calibration, is estimated to be 14:9 0:1. The mean ± upper giant branch CO index shows cluster-to-cluster scatter that (1) is larger than expected from the uncertainties in the photometric calibration, and (2) is consistent with a dispersion in CNO abundances comparable to that measured among halo stars. The luminosity functions (LFs) of upper giant branch stars in the program clusters tend to be steeper than those in the halo clusters NGC 288, NGC 362, and NGC 7089.
    [Show full text]
  • Planetary Nebulae
    Planetary Nebulae A planetary nebula is a kind of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from old red giant stars late in their lives. The term "planetary nebula" is a misnomer that originated in the 1780s with astronomer William Herschel because when viewed through his telescope, these objects appeared to him to resemble the rounded shapes of planets. Herschel's name for these objects was popularly adopted and has not been changed. They are a relatively short-lived phenomenon, lasting a few tens of thousands of years, compared to a typical stellar lifetime of several billion years. The mechanism for formation of most planetary nebulae is thought to be the following: at the end of the star's life, during the red giant phase, the outer layers of the star are expelled by strong stellar winds. Eventually, after most of the red giant's atmosphere is dissipated, the exposed hot, luminous core emits ultraviolet radiation to ionize the ejected outer layers of the star. Absorbed ultraviolet light energizes the shell of nebulous gas around the central star, appearing as a bright colored planetary nebula at several discrete visible wavelengths. Planetary nebulae may play a crucial role in the chemical evolution of the Milky Way, returning material to the interstellar medium from stars where elements, the products of nucleosynthesis (such as carbon, nitrogen, oxygen and neon), have been created. Planetary nebulae are also observed in more distant galaxies, yielding useful information about their chemical abundances. In recent years, Hubble Space Telescope images have revealed many planetary nebulae to have extremely complex and varied morphologies.
    [Show full text]
  • Spatial Distribution of Galactic Globular Clusters: Distance Uncertainties and Dynamical Effects
    Juliana Crestani Ribeiro de Souza Spatial Distribution of Galactic Globular Clusters: Distance Uncertainties and Dynamical Effects Porto Alegre 2017 Juliana Crestani Ribeiro de Souza Spatial Distribution of Galactic Globular Clusters: Distance Uncertainties and Dynamical Effects Dissertação elaborada sob orientação do Prof. Dr. Eduardo Luis Damiani Bica, co- orientação do Prof. Dr. Charles José Bon- ato e apresentada ao Instituto de Física da Universidade Federal do Rio Grande do Sul em preenchimento do requisito par- cial para obtenção do título de Mestre em Física. Porto Alegre 2017 Acknowledgements To my parents, who supported me and made this possible, in a time and place where being in a university was just a distant dream. To my dearest friends Elisabeth, Robert, Augusto, and Natália - who so many times helped me go from "I give up" to "I’ll try once more". To my cats Kira, Fen, and Demi - who lazily join me in bed at the end of the day, and make everything worthwhile. "But, first of all, it will be necessary to explain what is our idea of a cluster of stars, and by what means we have obtained it. For an instance, I shall take the phenomenon which presents itself in many clusters: It is that of a number of lucid spots, of equal lustre, scattered over a circular space, in such a manner as to appear gradually more compressed towards the middle; and which compression, in the clusters to which I allude, is generally carried so far, as, by imperceptible degrees, to end in a luminous center, of a resolvable blaze of light." William Herschel, 1789 Abstract We provide a sample of 170 Galactic Globular Clusters (GCs) and analyse its spatial distribution properties.
    [Show full text]
  • The Midnight Sky: Familiar Notes on the Stars and Planets, Edward Durkin, July 15, 1869 a Good Way to Start – Find North
    The expression "dog days" refers to the period from July 3 through Aug. 11 when our brightest night star, SIRIUS (aka the dog star), rises in conjunction* with the sun. Conjunction, in astronomy, is defined as the apparent meeting or passing of two celestial bodies. TAAS Fabulous Fifty A program for those new to astronomy Friday Evening, July 20, 2018, 8:00 pm All TAAS and other new and not so new astronomers are welcome. What is the TAAS Fabulous 50 Program? It is a set of 4 meetings spread across a calendar year in which a beginner to astronomy learns to locate 50 of the most prominent night sky objects visible to the naked eye. These include stars, constellations, asterisms, and Messier objects. Methodology 1. Meeting dates for each season in year 2018 Winter Jan 19 Spring Apr 20 Summer Jul 20 Fall Oct 19 2. Locate the brightest and easiest to observe stars and associated constellations 3. Add new prominent constellations for each season Tonight’s Schedule 8:00 pm – We meet inside for a slide presentation overview of the Summer sky. 8:40 pm – View night sky outside The Midnight Sky: Familiar Notes on the Stars and Planets, Edward Durkin, July 15, 1869 A Good Way to Start – Find North Polaris North Star Polaris is about the 50th brightest star. It appears isolated making it easy to identify. Circumpolar Stars Polaris Horizon Line Albuquerque -- 35° N Circumpolar Stars Capella the Goat Star AS THE WORLD TURNS The Circle of Perpetual Apparition for Albuquerque Deneb 1 URSA MINOR 2 3 2 URSA MAJOR & Vega BIG DIPPER 1 3 Draco 4 Camelopardalis 6 4 Deneb 5 CASSIOPEIA 5 6 Cepheus Capella the Goat Star 2 3 1 Draco Ursa Minor Ursa Major 6 Camelopardalis 4 Cassiopeia 5 Cepheus Clock and Calendar A single map of the stars can show the places of the stars at different hours and months of the year in consequence of the earth’s two primary movements: Daily Clock The rotation of the earth on it's own axis amounts to 360 degrees in 24 hours, or 15 degrees per hour (360/24).
    [Show full text]
  • The Hypergiants VY Canis Majoris, Eta Carinae, V766 Centauri and The
    Sixteenth Marcel Grossmann Meeting Contribution ID: 967 Type: Talk in the parallel session The hypergiants VY Canis Majoris, Eta Carinae, V766 Centauri and the red supergiants Betelgeuse, Antares and Aldebaran in the 2.5K SGQ AAVSO database Thursday, 8 July 2021 16:35 (7 minutes) I observe variable stars since 1997. The “candidacy” of Mira Ceti as Betlehem Star because close to Jupiter- Saturn triple conjunction of 6-7 b.C. started at Pontifical University of Lateran and continued in Yale (2001- 2004). Maxima correlation function ruled out Mira for having two consecutive bright maxima, but this prop- erty was confirmed in the “oldest” Myra-type: R Leonis, R Hydrae and Chi Cygni, from their almostfour- century-long lightcurves. To a bright maximum normally a dim one follows, as the correlation function of their consecutive maxima shows. These studies were supported by historical and personal visual observations. Since 2011 I observe firstmag- nitude variable stars, with airmass correction to reach 0.01 magnitudes accuracy with naked eye. AAVSO observer Sebastian Otero first claimed this accuracy, as for NovaCentauri 2013, observed by me fromPorto Alegre and Rio de Janeiro. Betelgeuse’s 801 observations in 10 years, include the deep minimum of 2020. My SGQ contributions to AAVSO-database, paralleled with Betelgeuse’s V-band measurements, help to define the “personal equations” present in all 25M visual observations before CCD era (1911-on) going back to 1893 for Betelgeuse. The temporal extension of lightcurves is crucial to understand the stellar behaviour. More complicate cases are Antares and Aldebaran, less variable and with distant comparison stars.
    [Show full text]
  • Single Star – Sylvie D
    ASTRONOMY AND ASTROPHYSICS – Single Star – Sylvie D. Vauclair and Gerard P. Vauclair SINGLE STARS Sylvie D. Vauclair Institut de Recherches en Astronomie et Planétologie, Université de Toulouse, Institut Universitaire de France, 14 avenue Edouard Belin, 31400 Toulouse, France Gérard P. Vauclair Institut de Recherches en Astronomie et Planétologie, Université de Toulouse, Centre National de la Recherche Scientifique, 14 avenue Edouard Belin, 31400 Toulouse, France Keywords: stars, stellar structure, stellar evolution, magnitudes, HR diagrams, asteroseismology, planetary nebulae, White Dwarfs, supernovae Contents 1. Introduction 2. Stellar observational data 2.1. Distances 2.1.1. Direct Methods 2.1.2. Indirect Methods 2.2. Stellar Luminosities 2.2.1. Apparent Magnitude 2.2.2. Absolute Magnitude 2.3. Surface Temperatures 2.3.1. Brightness Temperatures 2.3.2 Color Temperatures, Color Indices 2.3.3 Effective Temperatures 2.4 Stellar Spectroscopy 2.4.1. Spectral Types 2.4.2. Chemical Composition 2.4.3. Stellar Rotation and Magnetic Fields 2.6. Masses and Radii 3. Stellar structure and evolution 3.1. Color-Magnitude Diagrams 3.2. Stellar Structure 3.2.1. CharacteristicUNESCO Stellar Time Scales – EOLSS 3.2.2. The Basic Equations of the Stellar Structure 3.2.3. ApproximateSAMPLE Solutions CHAPTERS 3.3. Stellar Evolution 3.3.1. Stellar Evolutionary Codes 3.3.2. Stellar Evolution before the Main Sequence 3.3.3 The Main Sequence 3.3.4 Post Main Sequence Tracks 3.3.5 HR Diagrams of Stellar Clusters 3.4. Stars and Stellar Environment: Recent Developments 3.4.1 Atomic Diffusion 3.4.2 Rotation and Rotational Braking ©Encyclopedia of Life Support Systems (EOLSS) ASTRONOMY AND ASTROPHYSICS – Single Star – Sylvie D.
    [Show full text]
  • 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 ................................................................................
    [Show full text]
  • Globular Clusters in the Inner Galaxy Classified from Dynamical Orbital
    MNRAS 000,1{17 (2019) Preprint 14 November 2019 Compiled using MNRAS LATEX style file v3.0 Globular clusters in the inner Galaxy classified from dynamical orbital criteria Angeles P´erez-Villegas,1? Beatriz Barbuy,1 Leandro Kerber,2 Sergio Ortolani3 Stefano O. Souza 1 and Eduardo Bica,4 1Universidade de S~aoPaulo, IAG, Rua do Mat~ao 1226, Cidade Universit´aria, S~ao Paulo 05508-900, Brazil 2Universidade Estadual de Santa Cruz, Rodovia Jorge Amado km 16, Ilh´eus 45662-000, Brazil 3Dipartimento di Fisica e Astronomia `Galileo Galilei', Universit`adi Padova, Vicolo dell'Osservatorio 3, Padova, I-35122, Italy 4Universidade Federal do Rio Grande do Sul, Departamento de Astronomia, CP 15051, Porto Alegre 91501-970, Brazil Accepted XXX. Received YYY; in original form ZZZ ABSTRACT Globular clusters (GCs) are the most ancient stellar systems in the Milky Way. There- fore, they play a key role in the understanding of the early chemical and dynamical evolution of our Galaxy. Around 40% of them are placed within ∼ 4 kpc from the Galactic center. In that region, all Galactic components overlap, making their disen- tanglement a challenging task. With Gaia DR2, we have accurate absolute proper mo- tions for the entire sample of known GCs that have been associated with the bulge/bar region. Combining them with distances, from RR Lyrae when available, as well as ra- dial velocities from spectroscopy, we can perform an orbital analysis of the sample, employing a steady Galactic potential with a bar. We applied a clustering algorithm to the orbital parameters apogalactic distance and the maximum vertical excursion from the plane, in order to identify the clusters that have high probability to belong to the bulge/bar, thick disk, inner halo, or outer halo component.
    [Show full text]