Symposium on Telescope Science
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Academic Reading in Science Copyright 2014 © Chris Elvin Copyright Notice
Academic Reading in Science Copyright 2014 © Chris Elvin Copyright Notice Academic Reading in Science contains adaptations of Wikipedia copyrighted material. All pages containing these adaptations can be identified by the logo below; This logo is visible at the foot of every page in which Wikipedia articles have been adapted. Furthermore, all adaptations of Wikipedia sources show a URL at the foot of the article which you may use to access the original article. Pages which do not show the logo above are the copyright of the author Chris Elvin, and may not be used without permission. Creative Commons Deed You are free: to Share—to copy, distribute and transmit the work, and to Remix—to adapt the work Under the following conditions: Attribution—You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work.) Share Alike—If you alter, transform, or build upon this work, you may distribute the resulting work only under the same, similar or a compatible license. With the understanding that: Waiver—Any of the above conditions can be waived if you get permission from the copyright holder. Other Rights—In no way are any of the following rights affected by the license: your fair dealing or fair use rights; the author’s moral rights; and rights other persons may have either in the work itself or in how the work is used, such as publicity or privacy rights. Notice—For any reuse or distribution, you must make clear to others the license terms of this work. -
The Very Long Mystery of Epsilon Aurigae
A Unique Eclipsing Variable TheThe VeryVery LongLong MMysteryystery ofof EpsilonEpsilon AAurigaeurigae robertrobert e. sstenceltencel one of the great scientifi c advances of the 20th A remarkable naked-eye star century was the theory of stellar evolution, as physicists worked out not just how stars shine, but how they origi- will soon start dimming for nate, live, change, and die. To test theory against reality, however, astronomers had to determine accurate masses the eighth time since 1821. for many diff erent kinds of stars — and this meant analyz- What’s going on is still ing the motions of binary pairs. Theorists also needed the stars’ exact diameters, and this meant analyzing the light not exactly clear. curves of eclipsing binaries in particular. A century ago, S&T ILLUSTRATION BY CASEY REED giants of early astrophysics worked intensely on the prob- lem of eclipsing-binary analysis. Henry Norris Russell’s paper “On the Determination of the Orbital Elements of Eclipsing Variable Stars,” published in 1912, set the stage for what followed. BIG WHITE STAR, BIGGER BLACK PARTNER Epsilon Aurigae, hotter than the Sun and larger than Earth’s entire orbit, pours forth some 130,000 times the Sun’s light — which is why it shines as brightly as 3rd magnitude even from 2,000 light-years away. According to the currently favored model, a long, dark object will start sliding across its middle this summer. The object seems to be an opaque warped disk 10 a.u. wide and appearing roughly 1 a.u. tall. Whatever lies at its center seems to be hidden — though there’s also evidence that we see right through the center. -
Catalog of Nearby Exoplanets
Catalog of Nearby Exoplanets1 R. P. Butler2, J. T. Wright3, G. W. Marcy3,4, D. A Fischer3,4, S. S. Vogt5, C. G. Tinney6, H. R. A. Jones7, B. D. Carter8, J. A. Johnson3, C. McCarthy2,4, A. J. Penny9,10 ABSTRACT We present a catalog of nearby exoplanets. It contains the 172 known low- mass companions with orbits established through radial velocity and transit mea- surements around stars within 200 pc. We include 5 previously unpublished exo- planets orbiting the stars HD 11964, HD 66428, HD 99109, HD 107148, and HD 164922. We update orbits for 90 additional exoplanets including many whose orbits have not been revised since their announcement, and include radial ve- locity time series from the Lick, Keck, and Anglo-Australian Observatory planet searches. Both these new and previously published velocities are more precise here due to improvements in our data reduction pipeline, which we applied to archival spectra. We present a brief summary of the global properties of the known exoplanets, including their distributions of orbital semimajor axis, mini- mum mass, and orbital eccentricity. Subject headings: catalogs — stars: exoplanets — techniques: radial velocities 1Based on observations obtained at the W. M. Keck Observatory, which is operated jointly by the Uni- versity of California and the California Institute of Technology. The Keck Observatory was made possible by the generous financial support of the W. M. Keck Foundation. arXiv:astro-ph/0607493v1 21 Jul 2006 2Department of Terrestrial Magnetism, Carnegie Institute of Washington, 5241 Broad Branch Road NW, Washington, DC 20015-1305 3Department of Astronomy, 601 Campbell Hall, University of California, Berkeley, CA 94720-3411 4Department of Physics and Astronomy, San Francisco State University, San Francisco, CA 94132 5UCO/Lick Observatory, University of California, Santa Cruz, CA 95064 6Anglo-Australian Observatory, PO Box 296, Epping. -
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. -
25 Years of Cosmic Microwave Background Research at Inpe
Proceedings of the Brazilian Decimetric Array Workshop São José dos Campos, Brazil - July 28 – August 1, 2008 25 YEARS OF COSMIC MICROWAVE BACKGROUND RESEARCH AT INPE Carlos Alexandre Wuensche and Thyrso Villela Divisão de Astrofísica - Instituto de Pesquisas Espaciais - INPE Av. dos Astronautas,1758 – 12201-970, São José dos Campos-SP, Brasil ABSTRACT This article is a report of 25 years of Cosmic Microwave Background activities at INPE. Starting from balloon flights to measure the dipole anisotropy caused by the Earth’s motion inside the CMB radiation field, whose radiometer was a prototype of the DMR radiometer on board COBE satellite, member of the group cross the 90s working both on CMB anisotropy and foreground measurements. In the 2000s, there was a shift to polarization measurements and to data analysis, mostly focusing on map cleaning, non-gaussianity studies and foreground characterization. INTRODUCTION The cosmic microwave background radiation (CMB) is one of the most important cosmological observables presently available to cosmologists. Its properties can unveil information, among others, about the inflationary period, the overall composition of the Universe ( Ω0), the existence of gravitational waves, the age of the Universe and other parameters related to the recombination and decoupling era (Hu and Dodelson, 2002). These observables are critical to understand the physical processes accounting for the formation and evolution of the Universe. The CMB is observed from a few GHz to a few hundreds of GHz. It also observed in various angular scales, varying from less than 1 arcmin to many degrees, each range of scales encoding information about specific physical processes from the early (or not so early) Universe. -
Whole Earth Telescope Observations of AM Canum Venaticorum – Discoseismology at Last
Astron. Astrophys. 332, 939–957 (1998) ASTRONOMY AND ASTROPHYSICS Whole Earth Telescope observations of AM Canum Venaticorum – discoseismology at last J.-E. Solheim1;14, J.L. Provencal2;15, P.A. Bradley2;16, G. Vauclair3, M.A. Barstow4, S.O. Kepler5, G. Fontaine6, A.D. Grauer7, D.E. Winget2, T.M.K. Marar8, E.M. Leibowitz9, P.-I. Emanuelsen1, M. Chevreton10, N. Dolez3, A. Kanaan5, P. Bergeron6, C.F. Claver2;17, J.C. Clemens2;18, S.J. Kleinman2, B.P. Hine12, S. Seetha8, B.N. Ashoka8, T. Mazeh9, A.E. Sansom4;19, R.W. Tweedy4, E.G. Meistasˇ 11;13, A. Bruvold1, and C.M. Massacand1 1 Nordlysobservatoriet, Institutt for Fysikk, Universitetet i Tromsø, N-9037 Tromsø, Norway 2 McDonald Observatory and Department of Astronomy, The University of Texas at Austin, Austin, TX 78712, USA 3 Observatoire Midi–Pyrenees, 14 Avenue E. Belin, F-31400 Toulouse, France 4 Department of Physics and Astronomy, University of Leicester, Leicester, LE1 7RH, UK 5 Instituto de Fisica, Universidade Federal do Rio Grande do Sul, 91500-970 Porto Alegre - RS, Brazil 6 Department de Physique, Universite´ de Montreal,´ C.P. 6128, Succ A., Montreal,´ PQ H3C 3J7, Canada 7 Department of Physics and Astronomy, University of Arkansas, 2801 S. University Ave, Little Rock, AR 72204, USA 8 Technical Physics Division, ISRO Satelite Centre, Airport Rd, Bangalore, 560 017 India 9 University of Tel Aviv, Department of Physics and Astronomy, Ramat Aviv, Tel Aviv 69978, Israel 10 Observatoire de Paris-Meudon, F-92195 Meudon Principal Cedex, France 11 Institute of Material Research and Applied Sciences, Vilnius University, Ciurlionio 29, Vilnius 2009, Lithuania 12 NASA Ames Research Center, M.S. -
1000 Cataclysmic Variables from the Catalina Real-Time Transient Survey
MNRAS 443, 3174–3207 (2014) doi:10.1093/mnras/stu1377 1000 cataclysmic variables from the Catalina Real-time Transient Survey E. Breedt,1‹ B. T. Gansicke,¨ 1 A. J. Drake,2 P. Rodr´ıguez-Gil,3,4 S. G. Parsons,5 T. R. Marsh,1 P. Szkody,6 M. R. Schreiber5 and S. G. Djorgovski2 1Department of Physics, University of Warwick, Coventry, CV4 7AL, UK 2California Institute of Technology, 1200 E. California Blvd, CA 91225, USA 3Instituto de Astrof´ısica de Canarias, V´ıa Lactea´ s/n, La Laguna, E-38205, Santa Cruz de Tenerife, Spain 4Departamento de Astrof´ısica, Universidad de La Laguna, La Laguna, E-38206, Santa Cruz de Tenerife, Spain 5Instituto de F´ısica y Astronom´ıa, Universidad de Valpara´ıso, Avenida Gran Bretana 1111, 2360102 Valpara´ıso, Chile 6Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195-1580, USA Downloaded from Accepted 2014 July 6. Received 2014 July 5; in original form 2014 May 13 ABSTRACT Over six years of operation, the Catalina Real-time Transient Survey (CRTS) has identified http://mnras.oxfordjournals.org/ 1043 cataclysmic variable (CV) candidates – the largest sample of CVs from a single survey to date. Here, we provide spectroscopic identification of 85 systems fainter than g ≥ 19, including three AM Canum Venaticorum binaries, one helium-enriched CV, one polar and one new eclipsing CV. We analyse the outburst properties of the full sample and show that it contains a large fraction of low-accretion-rate CVs with long outburst recurrence times. We argue that most of the high-accretion-rate dwarf novae in the survey footprint have already been found and that future CRTS discoveries will be mostly low-accretion-rate systems. -
UC Irvine UC Irvine Previously Published Works
UC Irvine UC Irvine Previously Published Works Title Astrophysics in 2006 Permalink https://escholarship.org/uc/item/5760h9v8 Journal Space Science Reviews, 132(1) ISSN 0038-6308 Authors Trimble, V Aschwanden, MJ Hansen, CJ Publication Date 2007-09-01 DOI 10.1007/s11214-007-9224-0 License https://creativecommons.org/licenses/by/4.0/ 4.0 Peer reviewed eScholarship.org Powered by the California Digital Library University of California Space Sci Rev (2007) 132: 1–182 DOI 10.1007/s11214-007-9224-0 Astrophysics in 2006 Virginia Trimble · Markus J. Aschwanden · Carl J. Hansen Received: 11 May 2007 / Accepted: 24 May 2007 / Published online: 23 October 2007 © Springer Science+Business Media B.V. 2007 Abstract The fastest pulsar and the slowest nova; the oldest galaxies and the youngest stars; the weirdest life forms and the commonest dwarfs; the highest energy particles and the lowest energy photons. These were some of the extremes of Astrophysics 2006. We attempt also to bring you updates on things of which there is currently only one (habitable planets, the Sun, and the Universe) and others of which there are always many, like meteors and molecules, black holes and binaries. Keywords Cosmology: general · Galaxies: general · ISM: general · Stars: general · Sun: general · Planets and satellites: general · Astrobiology · Star clusters · Binary stars · Clusters of galaxies · Gamma-ray bursts · Milky Way · Earth · Active galaxies · Supernovae 1 Introduction Astrophysics in 2006 modifies a long tradition by moving to a new journal, which you hold in your (real or virtual) hands. The fifteen previous articles in the series are referenced oc- casionally as Ap91 to Ap05 below and appeared in volumes 104–118 of Publications of V. -
On the Detection of Exoplanets Via Radial Velocity Doppler Spectroscopy
The Downtown Review Volume 1 Issue 1 Article 6 January 2015 On the Detection of Exoplanets via Radial Velocity Doppler Spectroscopy Joseph P. Glaser Cleveland State University Follow this and additional works at: https://engagedscholarship.csuohio.edu/tdr Part of the Astrophysics and Astronomy Commons How does access to this work benefit ou?y Let us know! Recommended Citation Glaser, Joseph P.. "On the Detection of Exoplanets via Radial Velocity Doppler Spectroscopy." The Downtown Review. Vol. 1. Iss. 1 (2015) . Available at: https://engagedscholarship.csuohio.edu/tdr/vol1/iss1/6 This Article is brought to you for free and open access by the Student Scholarship at EngagedScholarship@CSU. It has been accepted for inclusion in The Downtown Review by an authorized editor of EngagedScholarship@CSU. For more information, please contact [email protected]. Glaser: Detection of Exoplanets 1 Introduction to Exoplanets For centuries, some of humanity’s greatest minds have pondered over the possibility of other worlds orbiting the uncountable number of stars that exist in the visible universe. The seeds for eventual scientific speculation on the possibility of these "exoplanets" began with the works of a 16th century philosopher, Giordano Bruno. In his modernly celebrated work, On the Infinite Universe & Worlds, Bruno states: "This space we declare to be infinite (...) In it are an infinity of worlds of the same kind as our own." By the time of the European Scientific Revolution, Isaac Newton grew fond of the idea and wrote in his Principia: "If the fixed stars are the centers of similar systems [when compared to the solar system], they will all be constructed according to a similar design and subject to the dominion of One." Due to limitations on observational equipment, the field of exoplanetary systems existed primarily in theory until the late 1980s. -
A Basic Requirement for Studying the Heavens Is Determining Where In
Abasic requirement for studying the heavens is determining where in the sky things are. To specify sky positions, astronomers have developed several coordinate systems. Each uses a coordinate grid projected on to the celestial sphere, in analogy to the geographic coordinate system used on the surface of the Earth. The coordinate systems differ only in their choice of the fundamental plane, which divides the sky into two equal hemispheres along a great circle (the fundamental plane of the geographic system is the Earth's equator) . Each coordinate system is named for its choice of fundamental plane. The equatorial coordinate system is probably the most widely used celestial coordinate system. It is also the one most closely related to the geographic coordinate system, because they use the same fun damental plane and the same poles. The projection of the Earth's equator onto the celestial sphere is called the celestial equator. Similarly, projecting the geographic poles on to the celest ial sphere defines the north and south celestial poles. However, there is an important difference between the equatorial and geographic coordinate systems: the geographic system is fixed to the Earth; it rotates as the Earth does . The equatorial system is fixed to the stars, so it appears to rotate across the sky with the stars, but of course it's really the Earth rotating under the fixed sky. The latitudinal (latitude-like) angle of the equatorial system is called declination (Dec for short) . It measures the angle of an object above or below the celestial equator. The longitud inal angle is called the right ascension (RA for short). -
A Paper for the Society for Astronomical Sciences
Three Years of Mira Variable Photometry: What Has Been Learned? Dale E. Mais Palomar Community College [email protected] David Richards Aberdeen & District Astronomical Society david@richwe b.f9.co.uk & Robert E. Stencel Dept. Physics & Astronomy University of Denver [email protected] Abstract The subject of micro-variability among Mira stars has received increased attention since DeLaverny et al. (1998) reported short-term brightness variations in 15 percent of the 250 Mira or Long Period Variable stars surveyed using the broadband 340 to 890 nm “Hp” filter on the HIPPARCOS satellite. The abrupt variations reported ranged 0.2 to 1.1 magnitudes, on time-scales between 2 to 100 hours, with a preponderance found nearer Mira minimum light phases. However, the HIPPARCOS sampling frequency was extremely sparse and required confirmation because of potentially important atmospheric dynamics and dust-formation physics that could be revealed. We report on Mira light curve sub-structure based on new CCD V and R band data, augmenting the known light curves of Hipparcos-selected long period variables [LPVs], and interpret same in terms of [1] interior structure, [2] atmospheric structure change, and/or [3] formation of circumstellar [CS] structure. We propose that the alleged micro-variability among Miras is largely undersampled, transient overtone pulsation structure in the light curves. © 2005 Society for Astronomical Science. 1. Introduction detected with HIPPARCOS, with no similar variations found for S and C-type Miras. These From European Space Agency's High Precision short-term variations were mostly detected when the Parallax Collecting Satellite, HIPPARCOS (ESA, star was fainter than Hp = 10 magnitude including 1997) mission data, deLaverny et al. -
Sulfur Hazes in Giant Exoplanet Atmospheres: Impacts on Reflected
Draft version February 28, 2017 Preprint typeset using LATEX style AASTeX6 v. 1.0 SULFUR HAZES IN GIANT EXOPLANET ATMOSPHERES: IMPACTS ON REFLECTED LIGHT SPECTRA Peter Gao1,2,3, Mark S. Marley, and Kevin Zahnle NASA Ames Research Center Moffett Field, CA 94035, USA Tyler D. Robinson4,5 Department of Astronomy and Astrophysics University of California Santa Cruz Santa Cruz, CA 95064, USA Nikole K. Lewis Space Telescope Science Institute Baltimore, MD 21218, USA 1Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA 2NASA Postdoctoral Program Fellow [email protected] 4Sagan Fellow 5NASA Astrobiology Institute’s Virtual Planetary Laboratory ABSTRACT Recent work has shown that sulfur hazes may arise in the atmospheres of some giant exoplanets due to the photolysis of H2S. We investigate the impact such a haze would have on an exoplanet’s geometric albedo spectrum and how it may affect the direct imaging results of WFIRST, a planned NASA space telescope. For temperate (250 K < Teq < 700 K) Jupiter–mass planets, photochemical destruction of H2S results in the production of 1 ppmv of S8 between 100 and 0.1 mbar, which, if cool enough, ∼ will condense to form a haze. Nominal haze masses are found to drastically alter a planet’s geometric albedo spectrum: whereas a clear atmosphere is dark at wavelengths between 0.5 and 1 µm due to molecular absorption, the addition of a sulfur haze boosts the albedo there to 0.7 due to scattering. ∼ Strong absorption by the haze shortward of 0.4 µm results in albedos <0.1, in contrast to the high albedos produced by Rayleigh scattering in a clear atmosphere.