February 2017 BRAS Newsletter
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Visual Astronomy Filter Research
Visual Astronomy Filter Research by Jim Thompson, P.Eng May 2010 Table of Contents: 1.0 The Great Filter Filibuster ...................................................................................... 3 2.0 The Human Eye...................................................................................................... 5 3.0 Planetary (Colour) Filter Research ......................................................................... 7 4.0 Using Planetary (Colour) Filters........................................................................... 12 5.0 Deep-Sky (Band Pass) Filter Research................................................................. 21 6.0 Using Deep-Sky (Band Pass) Filters..................................................................... 25 7.0 References............................................................................................................. 33 Appendix A – Colour Filter Plots ..................................................................................... 36 Appendix B – Deepsky Filter Plots .................................................................................. 43 List of Figures: Figure 1 An assortment of planetary (colour) filters ...................................................... 3 Figure 2 An example of deep-sky (band-pass) filters..................................................... 4 Figure 3 Human Eye Rod & Cone Density Distribution ................................................ 5 Figure 4 Human Eye Spectral Sensitivity...................................................................... -
Filter Performance Comparisons for Some Common Nebulae
Filter Performance Comparisons For Some Common Nebulae By Dave Knisely Light Pollution and various “nebula” filters have been around since the late 1970’s, and amateurs have been using them ever since to bring out detail (and even some objects) which were difficult to impossible to see before in modest apertures. When I started using them in the early 1980’s, specific information about which filter might work on a given object (or even whether certain filters were useful at all) was often hard to come by. Even those accounts that were available often had incomplete or inaccurate information. Getting some observational experience with the Lumicon line of filters helped, but there were still some unanswered questions. I wondered how the various filters would rank on- average against each other for a large number of objects, and whether there was a “best overall” filter. In particular, I also wondered if the much-maligned H-Beta filter was useful on more objects than the two or three targets most often mentioned in publications. In the summer of 1999, I decided to begin some more comprehensive observations to try and answer these questions and determine how to best use these filters overall. I formulated a basic survey covering a moderate number of emission and planetary nebulae to obtain some statistics on filter performance to try to address the following questions: 1. How do the various filter types compare as to what (on average) they show on a given nebula? 2. Is there one overall “best” nebula filter which will work on the largest number of objects? 3. -
Nitrogen Abundances in Planet-Harbouring Stars
A&A 418, 703–715 (2004) Astronomy DOI: 10.1051/0004-6361:20035717 & c ESO 2004 Astrophysics Nitrogen abundances in planet-harbouring stars A. Ecuvillon1, G. Israelian1,N.C.Santos2,3, M. Mayor3,R.J.Garc´ıa L´opez1,4, and S. Randich5 1 Instituto de Astrof´ısica de Canarias, 38200 La Laguna, Tenerife, Spain 2 Centro de Astronomia e Astrofisica de Universidade de Lisboa, Observatorio Astronomico de Lisboa, Tapada de Ajuda, 1349-018 Lisboa, Portugal 3 Observatoire de Gen`eve, 51 ch. des Maillettes, 1290 Sauverny, Switzerland 4 Departamento de Astrof´ısica, Universidad de La Laguna, Av. Astrof´ısico Francisco S´anchez s/n, 38206 La Laguna, Tenerife, Spain 5 INAF/Osservatorio Astrofisico di Arcetri, Largo Fermi 5, 50125 Firenze, Italy Received 20 November 2003 / Accepted 4 February 2004 Abstract. We present a detailed spectroscopic analysis of nitrogen abundances in 91 solar-type stars, 66 with and 25 without known planetary mass companions. All comparison sample stars and 28 planet hosts were analysed by spectral synthesis of the near-UV NH band at 3360 Å observed at high resolution with the VLT/UVES, while the near-IR N 7468 Å was measured in 31 objects. These two abundance indicators are in good agreement. We found that nitrogen abundance scales with that of iron in the metallicity range −0.6 < [Fe/H] < +0.4 with the slope 1.08 ± 0.05. Our results show that the bulk of nitrogen production at high metallicities was coupled with iron. We found that the nitrogen abundance distribution in stars with exoplanets is the high [Fe/H] extension of the curve traced by the comparison sample of stars with no known planets. -
Supernova Shocks in Molecular Clouds: Velocity Distribution of Molecular Hydrogen William T
Draft version September 6, 2019 Typeset using LATEX preprint2 style in AASTeX63 Supernova Shocks in Molecular Clouds: Velocity Distribution of Molecular Hydrogen William T. Reach,1 Le Ngoc Tram,1 Matthew Richter,2 Antoine Gusdorf,3 Curtis DeWitt,1 1Universities Space Research Association, MS 232-11, Moffett Field, CA 94035, USA 2University of California, Davis, CA USA 3Observatoire de Paris, Ecole´ normale sup´erieure, Sorbonne Universit´e,CNRS, LERMA, 75005 Paris, France ABSTRACT Supernovae from core-collapse of massive stars drive shocks into the molecular clouds from which the stars formed. Such shocks affect future star formation from the molecu- lar clouds, and the fast-moving, dense gas with compressed magnetic fields is associated with enhanced cosmic rays. This paper presents new theoretical modeling, using the Paris-Durham shock model, and new observations at high spectral resolution, using the Stratospheric Observatory for Infrared Astronomy (SOFIA), of the H2 S(5) pure rota- tional line from molecular shocks in the supernova remnant IC 443. We generate MHD models for non-steady-state shocks driven by the pressure of the IC 443 blast wave into gas of densities 103 to 105 cm−3. We present the first detailed derivation of the shape of the velocity profile for emission from H2 lines behind such shocks, taking into account the shock age, preshock density, and magnetic field. For preshock densities 103{105 −3 cm , the H2 emission arises from layers that extend 0.01{0.0003 pc behind the shock, respectively. The predicted shifts of line centers, and the line widths, of the H2 lines range from 20{2, and 30{4 km s−1, respectively. -
Three-Year Follow up of the Phase 3 Pollux Study of Daratumumab Plus
This is a repository copy of Three-Year Follow up of the Phase 3 Pollux Study of Daratumumab Plus Lenalidomide and Dexamethasone (D-Rd) Versus Lenalidomide and Dexamethasone (Rd) Alone in Relapsed or Refractory Multiple Myeloma (RRMM). White Rose Research Online URL for this paper: http://eprints.whiterose.ac.uk/157106/ Version: Accepted Version Proceedings Paper: Bahlis, N, Dimopoulos, MA, White, DJ et al. (14 more authors) (2018) Three-Year Follow up of the Phase 3 Pollux Study of Daratumumab Plus Lenalidomide and Dexamethasone (D-Rd) Versus Lenalidomide and Dexamethasone (Rd) Alone in Relapsed or Refractory Multiple Myeloma (RRMM). In: Blood. ASH 2018 – 60th American Society of Hematology Annual Meeting and Exposition, 01-04 Dec 2018, San Diego, CA. American Society of Hematology . https://doi.org/10.1182/blood-2018-99-112697 © 2018 by The American Society of Hematology. This is an author produced version of a conference abstract published in Blood. Uploaded in accordance with the publisher's self-archiving policy. Reuse Items deposited in White Rose Research Online are protected by copyright, with all rights reserved unless indicated otherwise. They may be downloaded and/or printed for private study, or other acts as permitted by national copyright laws. The publisher or other rights holders may allow further reproduction and re-use of the full text version. This is indicated by the licence information on the White Rose Research Online record for the item. Takedown If you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing [email protected] including the URL of the record and the reason for the withdrawal request. -
Naming the Extrasolar Planets
Naming the extrasolar planets W. Lyra Max Planck Institute for Astronomy, K¨onigstuhl 17, 69177, Heidelberg, Germany [email protected] Abstract and OGLE-TR-182 b, which does not help educators convey the message that these planets are quite similar to Jupiter. Extrasolar planets are not named and are referred to only In stark contrast, the sentence“planet Apollo is a gas giant by their assigned scientific designation. The reason given like Jupiter” is heavily - yet invisibly - coated with Coper- by the IAU to not name the planets is that it is consid- nicanism. ered impractical as planets are expected to be common. I One reason given by the IAU for not considering naming advance some reasons as to why this logic is flawed, and sug- the extrasolar planets is that it is a task deemed impractical. gest names for the 403 extrasolar planet candidates known One source is quoted as having said “if planets are found to as of Oct 2009. The names follow a scheme of association occur very frequently in the Universe, a system of individual with the constellation that the host star pertains to, and names for planets might well rapidly be found equally im- therefore are mostly drawn from Roman-Greek mythology. practicable as it is for stars, as planet discoveries progress.” Other mythologies may also be used given that a suitable 1. This leads to a second argument. It is indeed impractical association is established. to name all stars. But some stars are named nonetheless. In fact, all other classes of astronomical bodies are named. -
Platform-Independent Mobile Robot Communication
Philipp A. Baer Platform-Independent Development of Robot Communication Software kassel university press This work has been accepted by the faculty of Electrical Engineering and Computer Science of the University of Kassel as a thesis for acquiring the academic degree of Doktor der Ingenieurwissenschaften (Dr.-Ing.). Advisers: Prof. Dr. Kurt Geihs Prof. Dr. Gerhard K. Kraetzschmar Additional Doctoral Committee Members: Prof. Dr. Albert Zündorf Prof. Dr. Klaus David Defense day: 04th December 2008 Bibliographic information published by Deutsche Nationalbibliothek The Deutsche Nationalbibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data is available in the Internet at http://dnb.d-nb.de. Zugl.: Kassel, Univ., Diss. 2008 ISBN print: 978-3-89958-644-2 ISBN online: 978-3-89958-645-9 URN: urn:nbn:de:0002-6453 © 2008, kassel university press GmbH, Kassel www.upress.uni-kassel.de Printed by: Unidruckerei, University of Kassel Printed in Germany Für Mutti und Mama. Mutti, du bleibst unvergessen. * 29. September 1923 = 14. Oktober 2008 Contents List of Figuresv List of Tables vii Abstract ix I Introduction1 1 Introduction3 1.1 Motivation.........................................4 1.1.1 Software Structure................................5 1.1.2 Development Methodology...........................5 1.1.3 Communication.................................6 1.1.4 Configuration and Monitoring.........................6 1.2 Problem Analysis.....................................7 1.2.1 Development Methodology...........................7 1.2.2 Communication Infrastructure........................8 1.2.3 Resource Discovery...............................8 1.3 Solution Approach....................................9 1.4 Major Results........................................ 11 1.5 Overview.......................................... 12 2 Foundations 13 2.1 Autonomous Mobile Robots............................... 13 2.1.1 Hardware Architecture............................. 14 2.1.2 Robot Software................................. -
October 2017 BRAS Newsletter
October 2017 Issue Next Meeting: Monday, October 9th at 7PM at HRPO nd (2 Mondays, Highland Road Park Observatory) October Program: BRAS President John Nagle will. reveal how he researches and puts together his Observing Notes column for our newsletter each. month. What's In This Issue? HRPO’s Great American Eclipse Event Summary (Page 2) President’s Message Secretary's Summary Outreach Report - FAE Light Pollution Committee Report Recent Forum Entries 20/20 Vision Campaign Messages from the HRPO Spooky Spectrum Observe The Moon Night Natural Sky Conference HRPO 20th Anniversary Observing Notes – Phoenix & Mythology Like this newsletter? See past issues back to 2009 at http://brastro.org/newsletters.html Newsletter of the Baton Rouge Astronomical Society October 2017 President’s Message The first Sidewalk Astronomy of the season was a success. We had a good time, and About 100 people (adult and children) attended. Ben Toman live streamed on the BRAS Facebook page. See his description in this newsletter. A copy of the proposed, revised By-Laws should be in your mail soon. Read through them, and any proposed changes need to be communicated to me before the November meeting. Wally Pursell (who wrote the original and changed by-laws) and I worked last year on getting the By-Laws updated to the current BRAS policies, and we hope the revised By-Laws will need no revisions for a long time. We need more Globe at Night observations – we are behind in the observations compared to last year at this time. We also need observations of variable stars to help in a school project by a new BRAS member, Shreya. -
Arxiv:0809.1275V2
How eccentric orbital solutions can hide planetary systems in 2:1 resonant orbits Guillem Anglada-Escud´e1, Mercedes L´opez-Morales1,2, John E. Chambers1 [email protected], [email protected], [email protected] ABSTRACT The Doppler technique measures the reflex radial motion of a star induced by the presence of companions and is the most successful method to detect ex- oplanets. If several planets are present, their signals will appear combined in the radial motion of the star, leading to potential misinterpretations of the data. Specifically, two planets in 2:1 resonant orbits can mimic the signal of a sin- gle planet in an eccentric orbit. We quantify the implications of this statistical degeneracy for a representative sample of the reported single exoplanets with available datasets, finding that 1) around 35% percent of the published eccentric one-planet solutions are statistically indistinguishible from planetary systems in 2:1 orbital resonance, 2) another 40% cannot be statistically distinguished from a circular orbital solution and 3) planets with masses comparable to Earth could be hidden in known orbital solutions of eccentric super-Earths and Neptune mass planets. Subject headings: Exoplanets – Orbital dynamics – Planet detection – Doppler method arXiv:0809.1275v2 [astro-ph] 25 Nov 2009 Introduction Most of the +300 exoplanets found to date have been discovered using the Doppler tech- nique, which measures the reflex motion of the host star induced by the planets (Mayor & Queloz 1995; Marcy & Butler 1996). The diverse characteristics of these exoplanets are somewhat surprising. Many of them are similar in mass to Jupiter, but orbit much closer to their 1Carnegie Institution of Washington, Department of Terrestrial Magnetism, 5241 Broad Branch Rd. -
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. -
Urania Nr 5/2001
Eta Carinae To zdjęcie mgławicy otaczającej gwiazdę // Carinae uzyskano za po mocą telskopu kosmicznego Hubble a (K. Davidson i J. Mors). Porównując je z innymi zdjęciami, a w szczególności z obrazem wyko nanym 17 miesięcy wcześniej, Auto rzy stwierdzili rozprężanie się mgła wicy z szybkością ok. 2,5 min km/h, co prowadzi do wniosku, że rozpo częła ona swe istnienie około 150 lat temu. To bardzo ciekawy i intrygujący wynik. Otóż największy znany roz błysk )j Carinae miał miejsce w roku 1840. Wtedy gwiazda ta stała się naj jaśniejszą gwiazdą południowego nie ba i jasność jej przez krótki czas znacznie przewyższała blask gwiaz dy Canopus. Jednak pyłowy dysk ob serwowany wokół)/ Carinae wydaje się być znacznie młodszy - jego wiek (ekspansji) jest oceniany na 100 lat, co może znaczyć, że powstał w cza sie innego, mniejszego wybuchu ob serwowanego w roku 1890. Więcej na temat tego intrygują cego obiektu przeczytać można we wnątrz numeru, w artykule poświę conym tej gwieździe. NGC 6537 Obserwacje przeprowadzone teleskopem Hubble’a pokazały istnienie wielkich falowych struktur w mgławicy Czerwonego Pająka (NGC 6537) w gwiazdozbiorze Strzelca.Ta gorąca i „wietrzna” mgławica powstała wokół jednej z najgorętszych gwiazd Wszech świata, której wiatr gwiazdowy wiejący z prędkością 2000-4500 kilometrów na sekundę wytwarza fale o wysokości 100 miliardów kilometrów. Sama mgławica rozszerza się z szybkością 300 km/s. Jest też ona wyjątkowo gorąca — ok. 10000 K. Sama gwiazda, która utworzyła mgławicę, jest obecnie białym karłem i musi mieć temperaturę nie niższą niż pół miliona stopni — jest tak gorąca, że nie widać jej w obszarach uzyskanych teleskopem Hubble’a, a świeci głównie w promieniowaniu X. -
Pos(ICRC2019)832 † ∗ [email protected] Speaker
Probing Particle Diffusion around Two Nearby Pulsars with TeV Gamma-Ray Observations from HAWC PoS(ICRC2019)832 Hao Zhou∗ Los Alamos National Laboratory E-mail: [email protected] for the HAWC Collaborationy Nearby cosmic-ray accelerators, especially pulsar wind nebulae, are possible origins of the local multi-GeV positron excess. Pulsar Geminga and B0656+14, less than 300 pc from the Earth, have been postulated as the main sources of the positron excess. With one and half years of data, the HAWC gamma-ray observatory discovered very extended TeV gamma-ray structures produced from high-energy electrons and positrons around these two nearby middle-aged pulsars. Morphology studies suggest that the diffusion in the vicinity of these two pulsars is 100 times slower than the average in our Galaxy. This result provides important constraints on the origin of positron excess, but raises questions like why diffusion is so slow at high energies near these pulsars. With more than twice of data from the previous results, we now explore the possibility of energy-dependent diffusion at these sources. 36th International Cosmic Ray Conference -ICRC2019- July 24th - August 1st, 2019 Madison, WI, U.S.A. ∗Speaker. yFor a complete author list and acknowledgemets, see PoS(ICRC2019)1177 and http://www.hawc- observatory.org/collaboration/icrc2019.php c Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). http://pos.sissa.it/ Probing Particle Diffusion with HAWC Hao Zhou 1. Introduction Pulsar wind nebulae are known as efficient particle accelerators of electrons and positrons.