Planets in Spin-Orbit Misalignment and the Search for Stellar
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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. -
Correlations Between the Stellar, Planetary, and Debris Components of Exoplanet Systems Observed by Herschel⋆
A&A 565, A15 (2014) Astronomy DOI: 10.1051/0004-6361/201323058 & c ESO 2014 Astrophysics Correlations between the stellar, planetary, and debris components of exoplanet systems observed by Herschel J. P. Marshall1,2, A. Moro-Martín3,4, C. Eiroa1, G. Kennedy5,A.Mora6, B. Sibthorpe7, J.-F. Lestrade8, J. Maldonado1,9, J. Sanz-Forcada10,M.C.Wyatt5,B.Matthews11,12,J.Horner2,13,14, B. Montesinos10,G.Bryden15, C. del Burgo16,J.S.Greaves17,R.J.Ivison18,19, G. Meeus1, G. Olofsson20, G. L. Pilbratt21, and G. J. White22,23 (Affiliations can be found after the references) Received 15 November 2013 / Accepted 6 March 2014 ABSTRACT Context. Stars form surrounded by gas- and dust-rich protoplanetary discs. Generally, these discs dissipate over a few (3–10) Myr, leaving a faint tenuous debris disc composed of second-generation dust produced by the attrition of larger bodies formed in the protoplanetary disc. Giant planets detected in radial velocity and transit surveys of main-sequence stars also form within the protoplanetary disc, whilst super-Earths now detectable may form once the gas has dissipated. Our own solar system, with its eight planets and two debris belts, is a prime example of an end state of this process. Aims. The Herschel DEBRIS, DUNES, and GT programmes observed 37 exoplanet host stars within 25 pc at 70, 100, and 160 μm with the sensitiv- ity to detect far-infrared excess emission at flux density levels only an order of magnitude greater than that of the solar system’s Edgeworth-Kuiper belt. Here we present an analysis of that sample, using it to more accurately determine the (possible) level of dust emission from these exoplanet host stars and thereafter determine the links between the various components of these exoplanetary systems through statistical analysis. -
IAU Division C Working Group on Star Names 2019 Annual Report
IAU Division C Working Group on Star Names 2019 Annual Report Eric Mamajek (chair, USA) WG Members: Juan Antonio Belmote Avilés (Spain), Sze-leung Cheung (Thailand), Beatriz García (Argentina), Steven Gullberg (USA), Duane Hamacher (Australia), Susanne M. Hoffmann (Germany), Alejandro López (Argentina), Javier Mejuto (Honduras), Thierry Montmerle (France), Jay Pasachoff (USA), Ian Ridpath (UK), Clive Ruggles (UK), B.S. Shylaja (India), Robert van Gent (Netherlands), Hitoshi Yamaoka (Japan) WG Associates: Danielle Adams (USA), Yunli Shi (China), Doris Vickers (Austria) WGSN Website: https://www.iau.org/science/scientific_bodies/working_groups/280/ WGSN Email: [email protected] The Working Group on Star Names (WGSN) consists of an international group of astronomers with expertise in stellar astronomy, astronomical history, and cultural astronomy who research and catalog proper names for stars for use by the international astronomical community, and also to aid the recognition and preservation of intangible astronomical heritage. The Terms of Reference and membership for WG Star Names (WGSN) are provided at the IAU website: https://www.iau.org/science/scientific_bodies/working_groups/280/. WGSN was re-proposed to Division C and was approved in April 2019 as a functional WG whose scope extends beyond the normal 3-year cycle of IAU working groups. The WGSN was specifically called out on p. 22 of IAU Strategic Plan 2020-2030: “The IAU serves as the internationally recognised authority for assigning designations to celestial bodies and their surface features. To do so, the IAU has a number of Working Groups on various topics, most notably on the nomenclature of small bodies in the Solar System and planetary systems under Division F and on Star Names under Division C.” WGSN continues its long term activity of researching cultural astronomy literature for star names, and researching etymologies with the goal of adding this information to the WGSN’s online materials. -
Arxiv:2101.08801V1 [Astro-Ph.EP] 21 Jan 2021 Target Selection and Expanded Observational Techniques Have Type Stars (Zhou Et Al
DRAFT VERSION JANUARY 25, 2021 Typeset using LATEX twocolumn style in AASTeX63 A decade of radial-velocity monitoring of Vega and new limits on the presence of planets 1 2 2 3 2 SPENCER A. HURT , SAMUEL N. QUINN , DAVID W. LATHAM , ANDREW VANDERBURG , GILBERT A. ESQUERDO , 2 2 4, 5 2 2, ∗ MICHAEL L. CALKINS , PERRY BERLIND, RUTH ANGUS , CHRISTIAN A. LATHAM, AND GEORGE ZHOU 1Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309, USA 2Center for Astrophysics | Harvard & Smithsonian, 60 Garden St, Cambridge, MA 02138, USA 3Department of Astronomy, University of Wisconsin -Madison, 475 North Charter Street, Madison, WI 53706, USA 4Department of Astrophysics, American Museum of Natural History, 200 Central Park West, Manhattan, NY, USA 5Center for Computational Astrophysics, Flatiron Institute, 162 5th Avenue, Manhattan, NY, USA ABSTRACT We present an analysis of 1524 spectra of Vega spanning 10 years, in which we search for periodic radial velocity variations. A signal with a periodicity of 0.676 days and a semi-amplitude of ∼10 m s-1 is consistent with the rotation period measured over much shorter time spans by previous spectroscopic and spectropolari- metric studies, confirming the presence of surface features on this A0 star. The timescale of evolution of these features can provide insight into the mechanism that sustains the weak magnetic fields in normal A type stars. Modeling the radial velocities with a Gaussian process using a quasi-periodic kernel suggests that the charac- teristic spot evolution timescale is ∼180 days, though we cannot exclude the possibility that it is much longer. -
Culmination of a Constellation
Culmination of a Constellation Over any night, stars and constellations in the sky will appear to move from east to west due to the Earth’s rotation on its axis. A constellation will culminate (reach its highest point in the sky for your location) when it centres on the meridian - an imaginary line that runs across the sky from north to south and also passes through the zenith (the point high in the sky directly above your head). For example: When to Observe Constellations The taBle shows the approximate time (AEST) constellations will culminate around the middle (15th day) of each month. Constellations will culminate 2 hours earlier for each successive month. Note: add an hour to the given time when daylight saving time is in effect. The time “12” is midnight. Sunrise/sunset times are rounded off to the nearest half an hour. Sun- Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Rise 5am 5:30 6am 6am 7am 7am 7am 6:30 6am 5am 4:30 4:30 Set 7pm 6:30 6pm 5:30 5pm 5pm 5pm 5:30 6pm 6pm 6:30 7pm And 5am 3am 1am 11pm 9pm Aqr 5am 3am 1am 11pm 9pm Aql 4am 2am 12 10pm 8pm Ara 4am 2am 12 10pm 8pm Ari 5am 3am 1am 11pm 9pm Aur 10pm 8pm 4am 2am 12 Boo 3am 1am 11pm 9pm 7pm Cnc 1am 11pm 9pm 7pm 3am CVn 3am 1am 11pm 9pm 7pm CMa 11pm 9pm 7pm 3am 1am Cap 5am 3am 1am 11pm 9pm 7pm Car 2am 12 10pm 8pm 6pm Cen 4am 2am 12 10pm 8pm 6pm Cet 4am 2am 12 10pm 8pm Cha 3am 1am 11pm 9pm 7pm Col 10pm 8pm 4am 2am 12 Com 3am 1am 11pm 9pm 7pm CrA 3am 1am 11pm 9pm 7pm CrB 4am 2am 12 10pm 8pm Crv 3am 1am 11pm 9pm 7pm Cru 3am 1am 11pm 9pm 7pm Cyg 5am 3am 1am 11pm 9pm 7pm Del -
CCD Double Star Measurements - Personal Observations: #Report 1
Vol. 8 No. 3 July 1, 2012 Journal of Double Star Observations Page 193 CCD Double Star Measurements - Personal Observations: #Report 1 Giuseppe Micello Bologna Emilia Romagna - Italy EMAIL: [email protected] Abstract: This report submits CCD measurements of 49 pairs, observed in the period No- vember 2011 – January 2012. Possible new pairs, not cataloged in the Washington Double Star Catalog, are suggested. Orionis (precise coordinate from the Aladin Sky At- Introduction las: 05:19:06.14 +02:34:27.0, Figure 3) and new pair Between November 2011 and January 2012, I in system STF 721/GUI 7/BU 557 (precise coordinate made measurements of 49 double and multiple stars. from the Aladin Sky Atlas: 05:29:39.01 +03:06:47.5, For these measurements, I used a Schmidt- Figure 4). Cassegrain 235/2350 and a Maksutov-Cassegrain In this system, GUI 7AD is a neglected double 150/1800 on equatorial mount and the optical train star and we have only one measurement, dating back composed of a CCD camera, Imaging Source to 1904. DMK21AU, and an IR Cut Filter on Flip Mirror. The method is the same that I reported in a pre- Acknowledgements vious papers [1, 2] where I used Reduc by Florent This research has made use of the catalogs pre- Losse for data reduction,. sent in The Aladin Sky Atlas. Astrometric measurements and references to im- I thank Florent Losse for excellent software Re- ages and notes, are included in Table 1. duc. This paper also includes new possible pairs not I thank the Washington Double Star Catalog and cataloged in the Washington Double Star Catalog [3]. -
Binocular Challenges
This page intentionally left blank Cosmic Challenge Listing more than 500 sky targets, both near and far, in 187 challenges, this observing guide will test novice astronomers and advanced veterans alike. Its unique mix of Solar System and deep-sky targets will have observers hunting for the Apollo lunar landing sites, searching for satellites orbiting the outermost planets, and exploring hundreds of star clusters, nebulae, distant galaxies, and quasars. Each target object is accompanied by a rating indicating how difficult the object is to find, an in-depth visual description, an illustration showing how the object realistically looks, and a detailed finder chart to help you find each challenge quickly and effectively. The guide introduces objects often overlooked in other observing guides and features targets visible in a variety of conditions, from the inner city to the dark countryside. Challenges are provided for viewing by the naked eye, through binoculars, to the largest backyard telescopes. Philip S. Harrington is the author of eight previous books for the amateur astronomer, including Touring the Universe through Binoculars, Star Ware, and Star Watch. He is also a contributing editor for Astronomy magazine, where he has authored the magazine’s monthly “Binocular Universe” column and “Phil Harrington’s Challenge Objects,” a quarterly online column on Astronomy.com. He is an Adjunct Professor at Dowling College and Suffolk County Community College, New York, where he teaches courses in stellar and planetary astronomy. Cosmic Challenge The Ultimate Observing List for Amateurs PHILIP S. HARRINGTON CAMBRIDGE UNIVERSITY PRESS Cambridge, New York, Melbourne, Madrid, Cape Town, Singapore, Sao˜ Paulo, Delhi, Dubai, Tokyo, Mexico City Cambridge University Press The Edinburgh Building, Cambridge CB2 8RU, UK Published in the United States of America by Cambridge University Press, New York www.cambridge.org Information on this title: www.cambridge.org/9780521899369 C P. -
Shorter Communications a Reconstruction of a Tahitian Star Compass Based on Tupaia's “Chart for the Society Islands With
SHORTER COMMUNICATIONS A RECONSTRUCTION OF A TAHITIAN STAR COMPASS BASED ON TUPAIA’S “CHART FOR THE SOCIETY ISLANDS WITH OTAHEITE IN THE CENTER” ANNE DI PIAZZA Centre National de Recherche Scientifique—Centre de Recherche et de Documentation sur l’Océanie, Marseille When Europeans first ventured into the Pacific they had to grapple with three almost inconceivable notions: (i) that Pacific Islanders could guide their canoes successfully over long distances without instruments, while they, the Europeans, had spent centuries developing the compass, the sextant and the chronometer for navigation; (ii) that the islanders could hold mental maps, while they, the Europeans, had spent centuries developing ways of representing a curved world on a flat map; and (iii) that Pacific islanders could memorise and transmit knowledge of numerous star paths, as well as “wind” or “island compasses” orally, in contrast to the almanacs and various mathematical tables created over centuries in Europe. This encounter of two schools of navigation, one technically sophisticated and based largely on written knowledge, the other an oral system, has lead to considerable “méconnaissance” (Turnbull 1998)—not the least concerns methods of way finding and mental cartography. It is perhaps no surprise that Tupaia, the high priest and navigator encountered by Cook in Tahiti in 1769, had some difficulty convincing the Captain of the accuracy of the “situation of the islands” he knew of since hidden behind the Chart he drew was a body of local knowledge encompassing indigenous geography, astronomy and navigation. All of these domains were confounded into one “art of navigation” by Europeans. In Oceania, the “… art of navigation includes a sizable body of knowledge developed to meet the needs of ocean voyaging… local navigators have had to commit to memory their knowledge of the stars, sailing directions, seamarks…” (Goodenough and Thomas 1987: 3). -
One of the Most Useful Accessories an Amateur Can Possess Is One of the Ubiquitous Optical Filters
One of the most useful accessories an amateur can possess is one of the ubiquitous optical filters. Having been accessible previously only to the professional astronomer, they came onto the marker relatively recently, and have made a very big impact. They are useful, but don't think they're the whole answer! They can be a mixed blessing. From reading some of the advertisements in astronomy magazines you would be correct in thinking that they will make hitherto faint and indistinct objects burst into vivid observ ability. They don't. What the manufacturers do not mention is that regardless of the filter used, you will still need dark and transparent skies for the use of the filter to be worthwhile. Don't make the mistake of thinking that using a filter from an urban location will always make objects become clearer. The first and most immediately apparent item on the downside is that in all cases the use of a filter reduces the amount oflight that reaches the eye, often quite sub stantially. The brightness of the field of view and the objects contained therein is reduced. However, what the filter does do is select specific wavelengths of light emitted by an object, which may be swamped by other wavelengths. It does this by suppressing the unwanted wavelengths. This is particularly effective in observing extended objects such as emission nebulae and planetary nebulae. In the former case, use a filter that transmits light around the wavelength of 653.2 nm, which is the spectral line of hydrogen alpha (Ha), and is the wavelength oflight respons ible for the spectacular red colour seen in photographs of emission nebulae. -
Observing List
day month year Epoch 2000 local clock time: 2.00 Observing List for 17 11 2019 RA DEC alt az Constellation object mag A mag B Separation description hr min deg min 58 286 Andromeda Gamma Andromedae (*266) 2.3 5.5 9.8 yellow & blue green double star 2 3.9 42 19 40 283 Andromeda Pi Andromedae 4.4 8.6 35.9 bright white & faint blue 0 36.9 33 43 48 295 Andromeda STF 79 (Struve) 6 7 7.8 bluish pair 1 0.1 44 42 59 279 Andromeda 59 Andromedae 6.5 7 16.6 neat pair, both greenish blue 2 10.9 39 2 32 301 Andromeda NGC 7662 (The Blue Snowball) planetary nebula, fairly bright & slightly elongated 23 25.9 42 32.1 44 292 Andromeda M31 (Andromeda Galaxy) large sprial arm galaxy like the Milky Way 0 42.7 41 16 44 291 Andromeda M32 satellite galaxy of Andromeda Galaxy 0 42.7 40 52 44 293 Andromeda M110 (NGC205) satellite galaxy of Andromeda Galaxy 0 40.4 41 41 56 279 Andromeda NGC752 large open cluster of 60 stars 1 57.8 37 41 62 285 Andromeda NGC891 edge on galaxy, needle-like in appearance 2 22.6 42 21 30 300 Andromeda NGC7640 elongated galaxy with mottled halo 23 22.1 40 51 35 308 Andromeda NGC7686 open cluster of 20 stars 23 30.2 49 8 47 258 Aries 1 Arietis 6.2 7.2 2.8 fine yellow & pale blue pair 1 50.1 22 17 57 250 Aries 30 Arietis 6.6 7.4 38.6 pleasing yellow pair 2 37 24 39 59 253 Aries 33 Arietis 5.5 8.4 28.6 yellowish-white & blue pair 2 40.7 27 4 59 239 Aries 48, Epsilon Arietis 5.2 5.5 1.5 white pair, splittable @ 150x 2 59.2 21 20 46 254 Aries 5, Gamma Arietis (*262) 4.8 4.8 7.8 nice bluish-white pair 1 53.5 19 18 49 258 Aries 9, Lambda Arietis -
Major Qualifying Project
The Search for Exoplanets A Major Qualifying Project Submitted by: Christian J. Iamartino To the faculty of: Worcester Polytechnic Institute In partial fulfillment of the requirements for the degree of: Bachelor of Science For the department of: PHYSICS Advised by: P.K. Aravind September 25, 2014 1 Table of Contents 1. Abstract ..................................................................................................................................................... 4 2. Motivation ................................................................................................................................................. 5 3. Project Objectives ..................................................................................................................................... 6 4. Introduction ............................................................................................................................................... 7 4.1 What are Exoplanets? ......................................................................................................................... 7 4.2 Why Search for Them? ....................................................................................................................... 8 4.3 A Brief History of Exoplanets, From Antiquity to Modern Times ..................................................... 9 4.3.1 Origins of the Planetary Sciences ................................................................................................ 9 4.3.2 The Emergence and Development of -
IAU WGSN 2019 Annual Report
IAU Division C Working Group on Star Names 2019 Annual Report Eric Mamajek (chair, USA) WG Members: Juan Antonio Belmote Avilés (Spain), Sze-leung Cheung (Thailand), Beatriz García (Argentina), Steven Gullberg (USA), Duane Hamacher (Australia), Susanne M. Hoffmann (Germany), Alejandro López (Argentina), Javier Mejuto (Honduras), Thierry Montmerle (France), Jay Pasachoff (USA), Ian Ridpath (UK), Clive Ruggles (UK), B.S. Shylaja (India), Robert van Gent (Netherlands), Hitoshi Yamaoka (Japan) WG Associates: Danielle Adams (USA), Yunli Shi (China), Doris Vickers (Austria) WGSN Website: https://www.iau.org/science/scientific_bodies/working_groups/280/ WGSN Email: [email protected] The Working Group on Star Names (WGSN) consists of an international group of astronomers with expertise in stellar astronomy, astronomical history, and cultural astronomy who research and catalog proper names for stars for use by the international astronomical community, and also to aid the recognition and preservation of intangible astronomical heritage. The Terms of Reference and membership for WG Star Names (WGSN) are provided at the IAU website: https://www.iau.org/science/scientific_bodies/working_groups/280/. WGSN was re-proposed to Division C and was approved in April 2019 as a functional WG whose scope extends beyond the normal 3-year cycle of IAU working groups. The WGSN was specifically called out on p. 22 of IAU Strategic Plan 2020-2030: “The IAU serves as the internationally recognised authority for assigning designations to celestial bodies and their surface features. To do so, the IAU has a number of Working Groups on various topics, most notably on the nomenclature of small bodies in the Solar System and planetary systems under Division F and on Star Names under Division C.” WGSN continues its long term activity of researching cultural astronomy literature for star names, and researching etymologies with the goal of adding this information to the WGSN’s online materials.