Betelgeuse and the Crab Nebula
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BAV Rundbrief Nr. 3 (2014)
BAV Rundbrief 2014 | Nr. 3 | 63. Jahrgang | ISSN 0405-5497 Bundesdeutsche Arbeitsgemeinschaft für Veränderliche Sterne e.V. (BAV) BAV Rundbrief 2014 | Nr. 3 | 63. Jahrgang | ISSN 0405-5497 Table of Contents G. Maintz Revised elements of AP CVn and BH Ser 137 R. Gröbel Lightcurve and period of four RR Lyrae stars in Ursa Major: AG UMa, AV UMa, BK UMa and CK UMa 139 Inhaltsverzeichnis G. Maintz Verbesserte Elemente von AP CVn und BH Ser 137 R. Gröbel Lichtkurve und Periode von vier RR-Lyrae-Sternen in Ursa Major: AG UMa, AV UMa, BK UMa und CK UMa 139 Beobachtungsberichte D. Böhme Ist MP Gem ein Bedeckungsveränderlicher? 146 E. Pollmann / Zwischenergebnisse der 28-Tau-Kampagne 149 W. Vollmann F. Vohla U Orionis - ein (B-R)-Schelm 152 K. Wenzel Visuelle Lichtkurve von S5 0716+71 für den Beobachtungszeit- raum von August 2013 bis April 2014 154 K. Bernhard / Datamining leicht gemacht: Onlinekataloge für Einsteiger 155 S. Hümmerich Aus der Literatur Uni Bonn Spektakuläre Doppelexplosion am Sternenhimmel 161 E. Wischnewski Beobachtungsaufruf für Eta Orionis 163 Aus der BAV D. Bannuscher Neuigkeiten aus dem BAV-Vereinsleben 164 BAV-Vorstand BAV-Tagung Programmpunkte 165 D. Bannuscher Veränderlichenbeobachter-Treffen 2014 in Hartha 167 J. Hübscher Die systematische Überwachung veränderlicher Sterne durch BAV-Beobachter 170 W. Braune Veränderliche Sterne in „Sterne und Weltraum“ 174 T. Lange Rudolf Obertrifter ist verstorben 175 P. Reinhard Erlebnisbericht Namibia 2014 176 Aus den Sektionen F. Walter Bericht der Sektion „Bedeckungsveränderliche“ 2012 - 2014 178 G. Maintz Bericht der Sektion RR-Lyrae-Sterne 2012 - 2014 179 G. Monninger Bericht der Sektion Delta-Scuti-Sterne 2012 - 2014 180 R. -
Standing on the Shoulders of Giants: New Mass and Distance Estimates
Draft version October 15, 2020 Typeset using LATEX twocolumn style in AASTeX63 Standing on the shoulders of giants: New mass and distance estimates for Betelgeuse through combined evolutionary, asteroseismic, and hydrodynamical simulations with MESA Meridith Joyce,1, 2 Shing-Chi Leung,3 Laszl´ o´ Molnar,´ 4, 5, 6 Michael Ireland,1 Chiaki Kobayashi,7, 8, 2 and Ken'ichi Nomoto8 1Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611, Australia 2ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), Australia 3TAPIR, Walter Burke Institute for Theoretical Physics, Mailcode 350-17, Caltech, Pasadena, CA 91125, USA 4Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Konkoly-Thege ´ut15-17, H-1121 Budapest, Hungary 5MTA CSFK Lendulet¨ Near-Field Cosmology Research Group, Konkoly-Thege ´ut15-17, H-1121 Budapest, Hungary 6ELTE E¨otv¨os Lor´and University, Institute of Physics, Budapest, 1117, P´azm´any P´eter s´et´any 1/A 7Centre for Astrophysics Research, Department of Physics, Astronomy and Mathematics, University of Hertfordshire, College Lane, Hatfield AL10 9AB, UK 8Kavli Institute for the Physics and Mathematics of the Universe (WPI),The University of Tokyo Institutes for Advanced Study, The University of Tokyo, Kashiwa, Chiba 277-8583, Japan (Dated: Accepted XXX. Received YYY; in original form ZZZ) ABSTRACT We conduct a rigorous examination of the nearby red supergiant Betelgeuse by drawing on the synthesis of new observational data and three different modeling techniques. Our observational results include the release of new, processed photometric measurements collected with the space-based SMEI instrument prior to Betelgeuse's recent, unprecedented dimming event. -
New Atmospheric Parameters and Spectral Interpolator for the MILES Cool Stars Kaushal Sharma1,2,3, Philippe Prugniel1,2, and Harinder P
A&A 585, A64 (2016) Astronomy DOI: 10.1051/0004-6361/201526111 & c ESO 2015 Astrophysics New atmospheric parameters and spectral interpolator for the MILES cool stars Kaushal Sharma1,2,3, Philippe Prugniel1,2, and Harinder P. Singh3,1,2 1 Université de Lyon, Université Lyon 1, 69622 Villeurbanne, France e-mail: [email protected] 2 CRAL, Observatoire de Lyon, CNRS UMR 5574, 69561 Saint-Genis Laval, France 3 Department of Physics and Astrophysics, University of Delhi, 110007 Delhi, India e-mail: [kaushal;hpsingh]@physics.du.ac.in Received 17 March 2015 / Accepted 18 October 2015 ABSTRACT Context. The full spectrum fitting of stellar spectra against a library of empirical spectra is a well-established approach to measure the atmospheric parameters of FGK stars with a high internal consistency. Extending it towards cooler stars still remains a challenge. Aims. We address this question by improving the interpolator of the Medium-resolution INT Library of Empirical Spectra (MILES) library in the low effective temperature regime (Teff < 4800 K), and we refine the determination of the parameters of the cool MILES stars. Methods. We use the ULySS package to determine the atmospheric parameters (Teff,logg and [Fe/H]), and measure the biases of the results with respect to our updated compilation of parameters calibrated against theoretical spectra. After correcting some systematic effects, we compute a new interpolator that we finally use to redetermine the atmospheric parameters homogeneously and assess the biases. Results. Based on an updated literature compilation, we determine Teff in a more accurate and unbiased manner compared to those determined with the original interpolator. -
Winter Constellations
Winter Constellations *Orion *Canis Major *Monoceros *Canis Minor *Gemini *Auriga *Taurus *Eradinus *Lepus *Monoceros *Cancer *Lynx *Ursa Major *Ursa Minor *Draco *Camelopardalis *Cassiopeia *Cepheus *Andromeda *Perseus *Lacerta *Pegasus *Triangulum *Aries *Pisces *Cetus *Leo (rising) *Hydra (rising) *Canes Venatici (rising) Orion--Myth: Orion, the great hunter. In one myth, Orion boasted he would kill all the wild animals on the earth. But, the earth goddess Gaia, who was the protector of all animals, produced a gigantic scorpion, whose body was so heavily encased that Orion was unable to pierce through the armour, and was himself stung to death. His companion Artemis was greatly saddened and arranged for Orion to be immortalised among the stars. Scorpius, the scorpion, was placed on the opposite side of the sky so that Orion would never be hurt by it again. To this day, Orion is never seen in the sky at the same time as Scorpius. DSO’s ● ***M42 “Orion Nebula” (Neb) with Trapezium A stellar nursery where new stars are being born, perhaps a thousand stars. These are immense clouds of interstellar gas and dust collapse inward to form stars, mainly of ionized hydrogen which gives off the red glow so dominant, and also ionized greenish oxygen gas. The youngest stars may be less than 300,000 years old, even as young as 10,000 years old (compared to the Sun, 4.6 billion years old). 1300 ly. 1 ● *M43--(Neb) “De Marin’s Nebula” The star-forming “comma-shaped” region connected to the Orion Nebula. ● *M78--(Neb) Hard to see. A star-forming region connected to the Orion Nebula. -
Ioptron AZ Mount Pro Altazimuth Mount Instruction
® iOptron® AZ Mount ProTM Altazimuth Mount Instruction Manual Product #8900, #8903 and #8920 This product is a precision instrument. Please read the included QSG before assembling the mount. Please read the entire Instruction Manual before operating the mount. If you have any questions please contact us at [email protected] WARNING! NEVER USE A TELESCOPE TO LOOK AT THE SUN WITHOUT A PROPER FILTER! Looking at or near the Sun will cause instant and irreversible damage to your eye. Children should always have adult supervision while observing. 2 Table of Content Table of Content ......................................................................................................................................... 3 1. AZ Mount ProTM Altazimuth Mount Overview...................................................................................... 5 2. AZ Mount ProTM Mount Assembly ........................................................................................................ 6 2.1. Parts List .......................................................................................................................................... 6 2.2. Identification of Parts ....................................................................................................................... 7 2.3. Go2Nova® 8407 Hand Controller .................................................................................................... 8 2.3.1. Key Description ....................................................................................................................... -
Analysis of Eclipsing Binary Data
analysis of eclipsing binary data A.E. Lynas-Gray and C. Causer October 2012 AS33 1 Introduction The purpose of this experiment is to verify physical and geometric characteristics of an eclipsing binary already published in the literature, using radial velocity and light curves provided. In carrying out the experiment, the most important thing is to appreciate how the masses, radii, shapes, temperatures and orbits of the two stars determine the observed light and radial velocity variations. The book by Hilditch (2001) is an excellent introduction to binary stars and is recommended reading. Once the period has been determined, masses, radii and effective temperatures of both components are estimated using a “back of an envelope” calculation; these results are then used as a starting ap- proximation in a light and radial velocity curve synthesis code. The idea is to reproduce observed light and radial velocity curves, but in practice “back of the envelope” results will need adjustment before a good agreement with observation is achieved. At the time of writing, only data for R Canis Majoris are provided. 2 Initial setup Begin by creating a xterm window in which commands can be typed. The window is created using the Mouse to click on the large “X” in the middle of the dock on the bottom of your screen. The large “X” may bob up and down a bit before the window appears. The steps detailed below provide the setup necessary for experiments carried out in the Astrophysics Laboratory. The .profile, .bashrc, .cups/lpoptions and .Xdefaults files in your home directory are changed as a result of carrying out steps listed below; if these files have been previously setup to carry out an experiment in another laboratory, please consult a demonstrator before proceeding. -
PHOTOMETRIC and SPECTROSCOPIC STUDY of R Cma*
PHOTOMETRIC AND SPECTROSCOPIC STUDY OF R CMa* K. R. RADHAKRISHNAN, M. B. K. SARMA, and K. D. ABHYANKAR Centre of Advances Study in Astronomy, Osmania University, Hyderabad, India (Received 19 July, 1983) Abstract. UBFlight curves and spectrograms of RCMa obtained with the 48-inch telescope of Japal- Rangapur Observatory during 1980-82 have been used for deriving the eclipse and orbital elements as well as the absolute dimensions of the components. The primary is found to be a Main-Sequence F2V star of mass 1.52 M and the secondary a subgiant star of spectral type G8 and mass 0.20 M which fills its Roche lobe, in agreement with Kopal and Shapley (1956) results, Kopal (1959), or Sahade's (1963) results. From a consideration of the possible evolution of this system it is concluded that a large fraction of the original mass of the secondary is lost from the system. A study of the period changes indicates the possible presence of a third component of mass of about 0.5 MQ which is most likely to be an M dwarf. 1. Introduction R Canis Majoris is the prototype of a group of Algol systems having very low mass function. It is known to exhibit peculiarities in its light curve that change from time to time and is thought to be surrounded by gas. It also shows changes in period which are not yet fully understood. Hence, this star was included in the photometric and spectroscopic observing programme of Japal-Rangapur Observatory. R CMa was observed photometrically with the 48-inch telescope in the standard UBV colors on 34 nights during 1980-82 covering nine minima. -
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. -
On Massive Dust Clumps in the Envelope of the Red Supergiant VY Canis Majoris
Astronomy & Astrophysics manuscript no. VYCMAclumps_CONTI_May2019 c ESO 2019 July 2, 2019 On massive dust clumps in the envelope of the red supergiant VY Canis Majoris ? T. Kaminski´ Center for Astrophysics | Harvard & Smithsonian, Smithsonian Astrophysical Observatory, e-mail: [email protected] Received; accepted ABSTRACT The envelope of the red supergiant VY CMa has long been considered an extreme example of episodic mass loss that is possibly taking place in other cool and massive evolved stars. Recent (sub-)millimeter observations of the envelope revealed the presence of massive dusty clumps within 800 mas from the star which reinforce the picture of drastic mass-loss phenomena in VY CMa. We present new ALMA observations at an angular resolution of 0.100and at an unprecedented sensitivity that reveal further details about the dusty clumps. We resolve more discrete features and identify a submillimeter counterpart of a more distant Clump SW known from visual observations. The brightest clump, named C, is marginally resolved in the observations. Gas seen against the resolved continuum emission of clump C produces a molecular spectrum in absorption, in lines of mainly sulfur-bearing species. Except for SW Clump, no molecular emission is found to be associated with the dusty clumps and we propose that the dusty structures have an atypically low gas content. We attempt to reproduce the properties of the dusty clumps through three-dimensional radiative-transfer modeling. Although a clump configuration explaining the observations is found, it is not unique. A very high optical depth of all clumps to the stellar radiation make the modeling very challenging and requires unrealistically high dust masses for one of them. -
Winter Observing Notes
Wynyard Planetarium & Observatory Winter Observing Notes Wynyard Planetarium & Observatory PUBLIC OBSERVING – Winter Tour of the Sky with the Naked Eye NGC 457 CASSIOPEIA eta Cas Look for Notice how the constellations 5 the ‘W’ swing around Polaris during shape the night Is Dubhe yellowish compared 2 Polaris to Merak? Dubhe 3 Merak URSA MINOR Kochab 1 Is Kochab orange Pherkad compared to Polaris? THE PLOUGH 4 Mizar Alcor Figure 1: Sketch of the northern sky in winter. North 1. On leaving the planetarium, turn around and look northwards over the roof of the building. To your right is a group of stars like the outline of a saucepan standing up on it’s handle. This is the Plough (also called the Big Dipper) and is part of the constellation Ursa Major, the Great Bear. The top two stars are called the Pointers. Check with binoculars. Not all stars are white. The colour shows that Dubhe is cooler than Merak in the same way that red-hot is cooler than white-hot. 2. Use the Pointers to guide you to the left, to the next bright star. This is Polaris, the Pole (or North) Star. Note that it is not the brightest star in the sky, a common misconception. Below and to the right are two prominent but fainter stars. These are Kochab and Pherkad, the Guardians of the Pole. Look carefully and you will notice that Kochab is slightly orange when compared to Polaris. Check with binoculars. © Rob Peeling, CaDAS, 2007 version 2.0 Wynyard Planetarium & Observatory PUBLIC OBSERVING – Winter Polaris, Kochab and Pherkad mark the constellation Ursa Minor, the Little Bear. -
Rochester Skies
A S T R O N O M Y Rochester Skies First Newsletter ¨ Freezing Star-Party ¨ March Over Rochester ¨ Constellation Prize Rochester Astronomy Club Newsletter Issue #1 Winter ‘06 RAC Grows Up Constellation Prize Star Party The Rochester Astron- From our favorite Our coldest month omy Club has been meeting segment, turns out one of growing. As the size Randy Hemann will our best attended increases, so do the lead us by the optics Star Parties. Dean possibilities. If you are through the constel- Johnson fills us in on curious what RAC is lation Hydra, point- Eagle Bluff January. all about, take a look at ing out deep sky gems “Who We Are...” along the way. Page 1 Page 3 Page 4 ing to feel some growing pains. First Newsletter We appreciate feedback and Rochester Skies Welcome to the first newsletter of the encourage participation. If you Contents Rochester Astronomy Club. We hope have ideas, articles or images, March Over Rochester Pg 2 you find it fun and informative. You please submit them. Hunting the Hunter Pg 8 might even want to keep it around— It’s a Little Known Fact Pg 11 could be worth something someday! “Rochester Skies In the Beginning is a newsletter by the Pg 11 We hope this newsletter will be- club, for the club.” Satellite Satellbright Pg 10 come a source of anticipation for Up-Coming Events Pg 12 our members. As we ramp up If you have questions, comments or material for the Rochester Skies newsletter, our editorial process, we are go- please contact our lead editor Duane Deal at [email protected] A. -
Educator's Guide: Orion
Legends of the Night Sky Orion Educator’s Guide Grades K - 8 Written By: Dr. Phil Wymer, Ph.D. & Art Klinger Legends of the Night Sky: Orion Educator’s Guide Table of Contents Introduction………………………………………………………………....3 Constellations; General Overview……………………………………..4 Orion…………………………………………………………………………..22 Scorpius……………………………………………………………………….36 Canis Major…………………………………………………………………..45 Canis Minor…………………………………………………………………..52 Lesson Plans………………………………………………………………….56 Coloring Book…………………………………………………………………….….57 Hand Angles……………………………………………………………………….…64 Constellation Research..…………………………………………………….……71 When and Where to View Orion…………………………………….……..…77 Angles For Locating Orion..…………………………………………...……….78 Overhead Projector Punch Out of Orion……………………………………82 Where on Earth is: Thrace, Lemnos, and Crete?.............................83 Appendix………………………………………………………………………86 Copyright©2003, Audio Visual Imagineering, Inc. 2 Legends of the Night Sky: Orion Educator’s Guide Introduction It is our belief that “Legends of the Night sky: Orion” is the best multi-grade (K – 8), multi-disciplinary education package on the market today. It consists of a humorous 24-minute show and educator’s package. The Orion Educator’s Guide is designed for Planetarians, Teachers, and parents. The information is researched, organized, and laid out so that the educator need not spend hours coming up with lesson plans or labs. This has already been accomplished by certified educators. The guide is written to alleviate the fear of space and the night sky (that many elementary and middle school teachers have) when it comes to that section of the science lesson plan. It is an excellent tool that allows the parents to be a part of the learning experience. The guide is devised in such a way that there are plenty of visuals to assist the educator and student in finding the Winter constellations.