A Hot Subdwarf-White Dwarf Super-Chandrasekhar Candidate
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Astrodynamics
Politecnico di Torino SEEDS SpacE Exploration and Development Systems Astrodynamics II Edition 2006 - 07 - Ver. 2.0.1 Author: Guido Colasurdo Dipartimento di Energetica Teacher: Giulio Avanzini Dipartimento di Ingegneria Aeronautica e Spaziale e-mail: [email protected] Contents 1 Two–Body Orbital Mechanics 1 1.1 BirthofAstrodynamics: Kepler’sLaws. ......... 1 1.2 Newton’sLawsofMotion ............................ ... 2 1.3 Newton’s Law of Universal Gravitation . ......... 3 1.4 The n–BodyProblem ................................. 4 1.5 Equation of Motion in the Two-Body Problem . ....... 5 1.6 PotentialEnergy ................................. ... 6 1.7 ConstantsoftheMotion . .. .. .. .. .. .. .. .. .... 7 1.8 TrajectoryEquation .............................. .... 8 1.9 ConicSections ................................... 8 1.10 Relating Energy and Semi-major Axis . ........ 9 2 Two-Dimensional Analysis of Motion 11 2.1 ReferenceFrames................................. 11 2.2 Velocity and acceleration components . ......... 12 2.3 First-Order Scalar Equations of Motion . ......... 12 2.4 PerifocalReferenceFrame . ...... 13 2.5 FlightPathAngle ................................. 14 2.6 EllipticalOrbits................................ ..... 15 2.6.1 Geometry of an Elliptical Orbit . ..... 15 2.6.2 Period of an Elliptical Orbit . ..... 16 2.7 Time–of–Flight on the Elliptical Orbit . .......... 16 2.8 Extensiontohyperbolaandparabola. ........ 18 2.9 Circular and Escape Velocity, Hyperbolic Excess Speed . .............. 18 2.10 CosmicVelocities -
Mid-Band Gravitational Wave Detection with Precision Atomic Sensors
Mid-band gravitational wave detection with precision atomic sensors Peter W. Graham Stanford Institute for Theoretical Physics, Department of Physics, Stanford University, Stanford, CA 94305 Jason M. Hogan Department of Physics, Stanford University, Stanford, CA 94305 E-mail: [email protected] Mark A. Kasevich Department of Physics, Stanford University, Stanford, CA 94305 Surjeet Rajendran Berkeley Center for Theoretical Physics, Department of Physics, University of California, Berkeley, CA 94720 Roger W. Romani Kavli Institute for Particle Astrophysics and Cosmology Department of Physics, Stanford University, Stanford, CA 94305. For the MAGIS collaboration Abstract. We assess the science reach and technical feasibility of a satellite mission based on precision atomic sensors configured to detect gravitational radiation. Conceptual advances in the past three years indicate that a two-satellite constellation with science payloads consisting of atomic sensors based on laser cooled atomic Sr can achieve scientifically interesting gravitational wave strain sensitivities in a frequency band between the LISA and LIGO detectors, roughly 30 mHz to 10 Hz. The discovery arXiv:1711.02225v1 [astro-ph.IM] 6 Nov 2017 potential of the proposed instrument ranges from from observation of new astrophysical sources (e.g. black hole and neutron star binaries) to searches for cosmological sources of stochastic gravitational radiation and searches for dark matter. Mid-band gravitational wave detection with precision atomic sensors 2 1. Overview The recent first direct detections of gravitational waves by LIGO represent the beginning of a new era in astronomy [1, 2, 3]. Gravitational wave astronomy can provide information about astrophysical systems and cosmology that is difficult or impossible to acquire by other methods. -
Binocular Universe: Sly Fox September 2010 Phil Harrington
Binocular Universe is available every month on Cloudynights.com Binocular Universe: Sly Fox September 2010 Phil Harrington ast month's Stellafane convention, held atop Breezy Hill outside of Springfield, Vermont, was the best in recent memory. The skies were the Lclearest we've had in years, giving us a chance to enjoy the beauty of the summer Milky Way, which stretched from horizon to horizon. Armed with my trusty 10x50 and 16x70 binoculars, I sat back in my reclining chair and swept the plane of our Galaxy in pursuit of some old friends and new conquests. Above: Summer star map from Star Watch by Phil Harrington Binocular Universe is available every month on Cloudynights.com Above: Finder chart for this month's Binocular Universe. Chart adapted from Touring the Universe through Binoculars Atlas (TUBA), www.philharrington.net/tuba.htm Binocular Universe is available every month on Cloudynights.com Here are a few gems I bumped into along the way as I viewed the tiny constellation of Vulpecula the Fox. Vulpecula is a faint summertime constellation wedged between Cygnus (the Swan) to the north and Sagitta (the Arrow) to the south. None of Vulpecula’s stars shine brighter than magnitude 4.5, so seeing a fox here is a tall order indeed. But the sly Fox holds many binocular treasures for those who the time to seek them out. Vulpecula was created in 1687 by the Polish astronomer Johannes Hevelius. His original drawing showed a small fox carrying a hapless goose in its mouth. He called the combination Vulpecula et Anser ("the little fox and the goose"). -
Analysis of New High-Precision Transit Light Curves of WASP-10 B: Starspot
Astronomy & Astrophysics manuscript no. wasp10 c ESO 2018 September 10, 2018 Analysis of new high-precision transit light curves of WASP-10 b: starspot occultations, small planetary radius, and high metallicity⋆ G. Maciejewski1,2, St. Raetz2, N.Nettelmann3, M. Seeliger2, Ch. Adam2, G. Nowak1, and R. Neuh¨auser2 1 Toru´nCentre for Astronomy, Nicolaus Copernicus University, Gagarina 11, PL–87100 Toru´n, Poland e-mail: [email protected] 2 Astrophysikalisches Institut und Universit¨ats-Sternwarte, Schillerg¨asschen 2–3, D–07745 Jena, Germany 3 Institut f¨ur Physik, Universit¨at Rostock, D–18051 Rostock, Germany Received ...; accepted ... ABSTRACT Context. The WASP-10 planetary system is intriguing because different values of radius have been reported for its transiting exoplanet. The host star exhibits activity in terms of photometric variability, which is caused by the rotational modulation of the spots. Moreover, a periodic modulation has been discovered in transit timing of WASP-10 b, which could be a sign of an additional body perturbing the orbital motion of the transiting planet. Aims. We attempt to refine the physical parameters of the system, in particular the planetary radius, which is crucial for studying the internal structure of the transiting planet. We also determine new mid-transit times to confirm or refute observed anomalies in transit timing. Methods. We acquired high-precision light curves for four transits of WASP-10 b in 2010. Assuming various limb-darkening laws, we generated best-fit models and redetermined parameters of the system. The prayer-bead method and Monte Carlo simulations were used to derive error estimates. -
Divinus Lux Observatory Bulletin: Report #28 100 Dave Arnold
Vol. 9 No. 2 April 1, 2013 Journal of Double Star Observations Page Journal of Double Star Observations VOLUME 9 NUMBER 2 April 1, 2013 Inside this issue: Using VizieR/Aladin to Measure Neglected Double Stars 75 Richard Harshaw BN Orionis (TYC 126-0781-1) Duplicity Discovery from an Asteroidal Occultation by (57) Mnemosyne 88 Tony George, Brad Timerson, John Brooks, Steve Conard, Joan Bixby Dunham, David W. Dunham, Robert Jones, Thomas R. Lipka, Wayne Thomas, Wayne H. Warren Jr., Rick Wasson, Jan Wisniewski Study of a New CPM Pair 2Mass 14515781-1619034 96 Israel Tejera Falcón Divinus Lux Observatory Bulletin: Report #28 100 Dave Arnold HJ 4217 - Now a Known Unknown 107 Graeme L. White and Roderick Letchford Double Star Measures Using the Video Drift Method - III 113 Richard L. Nugent, Ernest W. Iverson A New Common Proper Motion Double Star in Corvus 122 Abdul Ahad High Speed Astrometry of STF 2848 With a Luminera Camera and REDUC Software 124 Russell M. Genet TYC 6223-00442-1 Duplicity Discovery from Occultation by (52) Europa 130 Breno Loureiro Giacchini, Brad Timerson, Tony George, Scott Degenhardt, Dave Herald Visual and Photometric Measurements of a Selected Set of Double Stars 135 Nathan Johnson, Jake Shellenberger, Elise Sparks, Douglas Walker A Pixel Correlation Technique for Smaller Telescopes to Measure Doubles 142 E. O. Wiley Double Stars at the IAU GA 2012 153 Brian D. Mason Report on the Maui International Double Star Conference 158 Russell M. Genet International Association of Double Star Observers (IADSO) 170 Vol. 9 No. 2 April 1, 2013 Journal of Double Star Observations Page 75 Using VizieR/Aladin to Measure Neglected Double Stars Richard Harshaw Cave Creek, Arizona [email protected] Abstract: The VizierR service of the Centres de Donnes Astronomiques de Strasbourg (France) offers amateur astronomers a treasure trove of resources, including access to the most current version of the Washington Double Star Catalog (WDS) and links to tens of thousands of digitized sky survey plates via the Aladin Java applet. -
Electric Propulsion System Scaling for Asteroid Capture-And-Return Missions
Electric propulsion system scaling for asteroid capture-and-return missions Justin M. Little⇤ and Edgar Y. Choueiri† Electric Propulsion and Plasma Dynamics Laboratory, Princeton University, Princeton, NJ, 08544 The requirements for an electric propulsion system needed to maximize the return mass of asteroid capture-and-return (ACR) missions are investigated in detail. An analytical model is presented for the mission time and mass balance of an ACR mission based on the propellant requirements of each mission phase. Edelbaum’s approximation is used for the Earth-escape phase. The asteroid rendezvous and return phases of the mission are modeled as a low-thrust optimal control problem with a lunar assist. The numerical solution to this problem is used to derive scaling laws for the propellant requirements based on the maneuver time, asteroid orbit, and propulsion system parameters. Constraining the rendezvous and return phases by the synodic period of the target asteroid, a semi- empirical equation is obtained for the optimum specific impulse and power supply. It was found analytically that the optimum power supply is one such that the mass of the propulsion system and power supply are approximately equal to the total mass of propellant used during the entire mission. Finally, it is shown that ACR missions, in general, are optimized using propulsion systems capable of processing 100 kW – 1 MW of power with specific impulses in the range 5,000 – 10,000 s, and have the potential to return asteroids on the order of 103 104 tons. − Nomenclature -
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 ....................................................................................................................... -
Správa O Činnosti Organizácie SAV Za Rok 2017
Astronomický ústav SAV Správa o činnosti organizácie SAV za rok 2017 Tatranská Lomnica január 2018 Obsah osnovy Správy o činnosti organizácie SAV za rok 2017 1. Základné údaje o organizácii 2. Vedecká činnosť 3. Doktorandské štúdium, iná pedagogická činnosť a budovanie ľudských zdrojov pre vedu a techniku 4. Medzinárodná vedecká spolupráca 5. Vedná politika 6. Spolupráca s VŠ a inými subjektmi v oblasti vedy a techniky 7. Spolupráca s aplikačnou a hospodárskou sférou 8. Aktivity pre Národnú radu SR, vládu SR, ústredné orgány štátnej správy SR a iné organizácie 9. Vedecko-organizačné a popularizačné aktivity 10. Činnosť knižnično-informačného pracoviska 11. Aktivity v orgánoch SAV 12. Hospodárenie organizácie 13. Nadácie a fondy pri organizácii SAV 14. Iné významné činnosti organizácie SAV 15. Vyznamenania, ocenenia a ceny udelené organizácii a pracovníkom organizácie SAV 16. Poskytovanie informácií v súlade so zákonom o slobodnom prístupe k informáciám 17. Problémy a podnety pre činnosť SAV PRÍLOHY A Zoznam zamestnancov a doktorandov organizácie k 31.12.2017 B Projekty riešené v organizácii C Publikačná činnosť organizácie D Údaje o pedagogickej činnosti organizácie E Medzinárodná mobilita organizácie F Vedecko-popularizačná činnosť pracovníkov organizácie SAV Správa o činnosti organizácie SAV 1. Základné údaje o organizácii 1.1. Kontaktné údaje Názov: Astronomický ústav SAV Riaditeľ: Mgr. Martin Vaňko, PhD. Zástupca riaditeľa: Mgr. Peter Gömöry, PhD. Vedecký tajomník: Mgr. Marián Jakubík, PhD. Predseda vedeckej rady: RNDr. Luboš Neslušan, CSc. Člen snemu SAV: Mgr. Marián Jakubík, PhD. Adresa: Astronomický ústav SAV, 059 60 Tatranská Lomnica http://www.ta3.sk Tel.: 052/7879111 Fax: 052/4467656 E-mail: [email protected] Názvy a adresy detašovaných pracovísk: Astronomický ústav - Oddelenie medziplanetárnej hmoty Dúbravská cesta 9, 845 04 Bratislava Vedúci detašovaných pracovísk: Astronomický ústav - Oddelenie medziplanetárnej hmoty prof. -
The X-Ray Universe 2017
The X-ray Universe 2017 6−9 June 2017 Centro Congressi Frentani Rome, Italy A conference organised by the European Space Agency XMM-Newton Science Operations Centre National Institute for Astrophysics, Italian Space Agency University Roma Tre, La Sapienza University ABSTRACT BOOK Oral Communications and Posters Edited by Simone Migliari, Jan-Uwe Ness Organising Committees Scientific Organising Committee M. Arnaud Commissariat ´al’´energie atomique Saclay, Gif sur Yvette, France D. Barret (chair) Institut de Recherche en Astrophysique et Plan´etologie, France G. Branduardi-Raymont Mullard Space Science Laboratory, Dorking, Surrey, United Kingdom L. Brenneman Smithsonian Astrophysical Observatory, Cambridge, USA M. Brusa Universit`adi Bologna, Italy M. Cappi Istituto Nazionale di Astrofisica, Bologna, Italy E. Churazov Max-Planck-Institut f¨urAstrophysik, Garching, Germany A. Decourchelle Commissariat ´al’´energie atomique Saclay, Gif sur Yvette, France N. Degenaar University of Amsterdam, the Netherlands A. Fabian University of Cambridge, United Kingdom F. Fiore Osservatorio Astronomico di Roma, Monteporzio Catone, Italy F. Harrison California Institute of Technology, Pasadena, USA M. Hernanz Institute of Space Sciences (CSIC-IEEC), Barcelona, Spain A. Hornschemeier Goddard Space Flight Center, Greenbelt, USA V. Karas Academy of Sciences, Prague, Czech Republic C. Kouveliotou George Washington University, Washington DC, USA G. Matt Universit`adegli Studi Roma Tre, Roma, Italy Y. Naz´e Universit´ede Li`ege, Belgium T. Ohashi Tokyo Metropolitan University, Japan I. Papadakis University of Crete, Heraklion, Greece J. Hjorth University of Copenhagen, Denmark K. Poppenhaeger Queen’s University Belfast, United Kingdom N. Rea Instituto de Ciencias del Espacio (CSIC-IEEC), Spain T. Reiprich Bonn University, Germany M. Salvato Max-Planck-Institut f¨urextraterrestrische Physik, Garching, Germany N. -
National Radio Astronomy Observatory Quarterly
Qs V'O6?-AzIJJ NATIONAL RADIO ASTRONOMY OBSERVATORY QUARTERLY REPORT January 1 - March 31, 1990 APr TABLE OF CONTENTS A. TELESCOPE USAGE .1.. .. ... ............................... 1 B. 140-FOOT TELESCOPE1 ... ........ ............................. 1 C. 12-METER TELESCOPE6 ......... ............................. 6 D. VERY LARGE ARRAY9 .. ........ .............................. 9 E. SCIENTIFIC HIGHLIGHTS .. ........ ............................ 20 F. PUBLICATIONS ... ........ ................................ 21 G. CENTRAL DEVELOPMENT LABORATORY . ....... ....................... 21 H. GREEN BANK ELECTRONICS . ........ ........................... 23 I. 12-METER ELECTRONICS . ........ .............................. 25 J. VLA ELECTRONICS .. ........ ............................... 25 K. AIPS .. ........ .................................... 28 L. VLA COMPUTER .. ....... ................................ 28 M. VERY LONG BASELINE ARRAY . ........ .......................... 29 N. PERSONNEL ... .......... .................................. 32 APPENDIX A: LIST OF NRAO PREPRINTS A. TELESCOPE USAGE The NRAO telescopes have been scheduled for research and maintenance in the following manner during the first quarter of 1990. 140-ft 12-meter VIA Scheduled observing (hours) 1935.00 1772.25 1624.6 Scheduled maintenance and equipment changes 193.5 116.25 264.6 Scheduled tests and calibrations 127.25 261.50 261.6 Time lost 103.75 366.25 78.0 Actual observing 1831.25 1496.00 1546.7 B. 140-FOOT TELESCOPE The following line programs were conducted during the quarter. No. Observer(s) Program B-492 Bell, M. (Herzberg) Spectral survey of IRC+10216 over the Feldman, P (Herzberg) range 22.0-24.5 GHz. Matthews, H. (Herzberg) B-524 Bell, M. (Herzberg) . Studies at 17.5-24.5 GHz of heavy Avery, L. (Herzberg) molecule chemistry in shocked and Feldman, P. (Herzberg) unshocked gas in Orion. Matthews, H. (Herzberg) B-492 Bell, M. (Herzberg) Spectral survey of IRC+10216 over the Feldman, P. (Herzberg) range 22.0-24.5 GHz. Matthews, H. (Herzberg) B-525 Bell, M. -
The Extragalactic Distance Scale
The Extragalactic Distance Scale Published in "Stellar astrophysics for the local group" : VIII Canary Islands Winter School of Astrophysics. Edited by A. Aparicio, A. Herrero, and F. Sanchez. Cambridge ; New York : Cambridge University Press, 1998 Calibration of the Extragalactic Distance Scale By BARRY F. MADORE1, WENDY L. FREEDMAN2 1NASA/IPAC Extragalactic Database, Infrared Processing & Analysis Center, California Institute of Technology, Jet Propulsion Laboratory, Pasadena, CA 91125, USA 2Observatories, Carnegie Institution of Washington, 813 Santa Barbara St., Pasadena CA 91101, USA The calibration and use of Cepheids as primary distance indicators is reviewed in the context of the extragalactic distance scale. Comparison is made with the independently calibrated Population II distance scale and found to be consistent at the 10% level. The combined use of ground-based facilities and the Hubble Space Telescope now allow for the application of the Cepheid Period-Luminosity relation out to distances in excess of 20 Mpc. Calibration of secondary distance indicators and the direct determination of distances to galaxies in the field as well as in the Virgo and Fornax clusters allows for multiple paths to the determination of the absolute rate of the expansion of the Universe parameterized by the Hubble constant. At this point in the reduction and analysis of Key Project galaxies H0 = 72km/ sec/Mpc ± 2 (random) ± 12 [systematic]. Table of Contents INTRODUCTION TO THE LECTURES CEPHEIDS BRIEF SUMMARY OF THE OBSERVED PROPERTIES OF CEPHEID -
Not Surprising That the Method Begins to Break Down at This Point
152 ASTRONOMY: W. S. ADAMS hanced lines in the early F stars are normally so prominent that it is not surprising that the method begins to break down at this point. To illustrate the use of the formulae and curves we may select as il- lustrations a few stars of different spectral types and magnitudes. These are collected in Table II. The classification is from Mount Wilson determinations. TABLE H ~A M PARAIuAX srTATYP_________________ (a) I(b) (C) (a) (b) c) Mean Comp. Ob. Pi 10U96.... 7.6F5 -0.7 +0.7 +3.0 +6.5 4.7 5.8 5.7 +0#04 +0.04 Sun........ GO -0.5 +0.5 +3.0 +5.6 4.3 5.8 5.2 Lal. 38287.. 7.2 G5 -1.8 +1.5 +3.5 +7.4 +6.3 +6.2 7.3 +0.10 +0.09 a Arietis... 2.2K0O +2.5 -2.4 +0.2 +1.0 1.3 +0.2 0.8 +0.05 +0.09 aTauri.... 1.1K5 +3.0 -2.0 +0.5 -0.4 +1.9 +0.5 0.7 +0.08 +0.07 61' Cygni...6.3K8 -1.8 +5.8 +7.7 +8.2 9.3 8.9 8.8 +0.32 +0.31 Groom. 34..8.2 Ma -2.2 +6.8 +9.2 +10.2 10.5 10.4 10.4 +0.28 +0.28 The parallaxes are computed from the absolute magnitudes by the formula, to which reference has already been made, 5 logr = M - m - 5. The results are given in the next to the last column of the table, and the measured parallaxes in the final column.