Self-Study Report External Review of the Institute for Astronomy
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Cosmicflows-3: Cosmography of the Local Void
Draft version May 22, 2019 Preprint typeset using LATEX style AASTeX6 v. 1.0 COSMICFLOWS-3: COSMOGRAPHY OF THE LOCAL VOID R. Brent Tully, Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822, USA Daniel Pomarede` Institut de Recherche sur les Lois Fondamentales de l'Univers, CEA, Universite' Paris-Saclay, 91191 Gif-sur-Yvette, France Romain Graziani University of Lyon, UCB Lyon 1, CNRS/IN2P3, IPN Lyon, France Hel´ ene` M. Courtois University of Lyon, UCB Lyon 1, CNRS/IN2P3, IPN Lyon, France Yehuda Hoffman Racah Institute of Physics, Hebrew University, Jerusalem, 91904 Israel Edward J. Shaya University of Maryland, Astronomy Department, College Park, MD 20743, USA ABSTRACT Cosmicflows-3 distances and inferred peculiar velocities of galaxies have permitted the reconstruction of the structure of over and under densities within the volume extending to 0:05c. This study focuses on the under dense regions, particularly the Local Void that lies largely in the zone of obscuration and consequently has received limited attention. Major over dense structures that bound the Local Void are the Perseus-Pisces and Norma-Pavo-Indus filaments sepa- rated by 8,500 km s−1. The void network of the universe is interconnected and void passages are found from the Local Void to the adjacent very large Hercules and Sculptor voids. Minor filaments course through voids. A particularly interesting example connects the Virgo and Perseus clusters, with several substantial galaxies found along the chain in the depths of the Local Void. The Local Void has a substantial dynamical effect, causing a deviant motion of the Local Group of 200 − 250 km s−1. -
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. -
Simulating (Sub)Millimeter Observations of Exoplanet Atmospheres in Search of Water
University of Groningen Kapteyn Astronomical Institute Simulating (Sub)Millimeter Observations of Exoplanet Atmospheres in Search of Water September 5, 2018 Author: N.O. Oberg Supervisor: Prof. Dr. F.F.S. van der Tak Abstract Context: Spectroscopic characterization of exoplanetary atmospheres is a field still in its in- fancy. The detection of molecular spectral features in the atmosphere of several hot-Jupiters and hot-Neptunes has led to the preliminary identification of atmospheric H2O. The Atacama Large Millimiter/Submillimeter Array is particularly well suited in the search for extraterrestrial water, considering its wavelength coverage, sensitivity, resolving power and spectral resolution. Aims: Our aim is to determine the detectability of various spectroscopic signatures of H2O in the (sub)millimeter by a range of current and future observatories and the suitability of (sub)millimeter astronomy for the detection and characterization of exoplanets. Methods: We have created an atmospheric modeling framework based on the HAPI radiative transfer code. We have generated planetary spectra in the (sub)millimeter regime, covering a wide variety of possible exoplanet properties and atmospheric compositions. We have set limits on the detectability of these spectral features and of the planets themselves with emphasis on ALMA. We estimate the capabilities required to study exoplanet atmospheres directly in the (sub)millimeter by using a custom sensitivity calculator. Results: Even trace abundances of atmospheric water vapor can cause high-contrast spectral ab- sorption features in (sub)millimeter transmission spectra of exoplanets, however stellar (sub) millime- ter brightness is insufficient for transit spectroscopy with modern instruments. Excess stellar (sub) millimeter emission due to activity is unlikely to significantly enhance the detectability of planets in transit except in select pre-main-sequence stars. -
Open Batalha-Dissertation.Pdf
The Pennsylvania State University The Graduate School Eberly College of Science A SYNERGISTIC APPROACH TO INTERPRETING PLANETARY ATMOSPHERES A Dissertation in Astronomy and Astrophysics by Natasha E. Batalha © 2017 Natasha E. Batalha Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy August 2017 The dissertation of Natasha E. Batalha was reviewed and approved∗ by the following: Steinn Sigurdsson Professor of Astronomy and Astrophysics Dissertation Co-Advisor, Co-Chair of Committee James Kasting Professor of Geosciences Dissertation Co-Advisor, Co-Chair of Committee Jason Wright Professor of Astronomy and Astrophysics Eric Ford Professor of Astronomy and Astrophysics Chris Forest Professor of Meteorology Avi Mandell NASA Goddard Space Flight Center, Research Scientist Special Signatory Michael Eracleous Professor of Astronomy and Astrophysics Graduate Program Chair ∗Signatures are on file in the Graduate School. ii Abstract We will soon have the technological capability to measure the atmospheric compo- sition of temperate Earth-sized planets orbiting nearby stars. Interpreting these atmospheric signals poses a new challenge to planetary science. In contrast to jovian-like atmospheres, whose bulk compositions consist of hydrogen and helium, terrestrial planet atmospheres are likely comprised of high mean molecular weight secondary atmospheres, which have gone through a high degree of evolution. For example, present-day Mars has a frozen surface with a thin tenuous atmosphere, but 4 billion years ago it may have been warmed by a thick greenhouse atmosphere. Several processes contribute to a planet’s atmospheric evolution: stellar evolution, geological processes, atmospheric escape, biology, etc. Each of these individual processes affects the planetary system as a whole and therefore they all must be considered in the modeling of terrestrial planets. -
Mètodes De Detecció I Anàlisi D'exoplanetes
MÈTODES DE DETECCIÓ I ANÀLISI D’EXOPLANETES Rubén Soussé Villa 2n de Batxillerat Tutora: Dolors Romero IES XXV Olimpíada 13/1/2011 Mètodes de detecció i anàlisi d’exoplanetes . Índex - Introducció ............................................................................................. 5 [ Marc Teòric ] 1. L’Univers ............................................................................................... 6 1.1 Les estrelles .................................................................................. 6 1.1.1 Vida de les estrelles .............................................................. 7 1.1.2 Classes espectrals .................................................................9 1.1.3 Magnitud ........................................................................... 9 1.2 Sistemes planetaris: El Sistema Solar .............................................. 10 1.2.1 Formació ......................................................................... 11 1.2.2 Planetes .......................................................................... 13 2. Planetes extrasolars ............................................................................ 19 2.1 Denominació .............................................................................. 19 2.2 Història dels exoplanetes .............................................................. 20 2.3 Mètodes per detectar-los i saber-ne les característiques ..................... 26 2.3.1 Oscil·lació Doppler ........................................................... 27 2.3.2 Trànsits -
Planets and Exoplanets
NASE Publications Planets and exoplanets Planets and exoplanets Rosa M. Ros, Hans Deeg International Astronomical Union, Technical University of Catalonia (Spain), Instituto de Astrofísica de Canarias and University of La Laguna (Spain) Summary This workshop provides a series of activities to compare the many observed properties (such as size, distances, orbital speeds and escape velocities) of the planets in our Solar System. Each section provides context to various planetary data tables by providing demonstrations or calculations to contrast the properties of the planets, giving the students a concrete sense for what the data mean. At present, several methods are used to find exoplanets, more or less indirectly. It has been possible to detect nearly 4000 planets, and about 500 systems with multiple planets. Objetives - Understand what the numerical values in the Solar Sytem summary data table mean. - Understand the main characteristics of extrasolar planetary systems by comparing their properties to the orbital system of Jupiter and its Galilean satellites. The Solar System By creating scale models of the Solar System, the students will compare the different planetary parameters. To perform these activities, we will use the data in Table 1. Planets Diameter (km) Distance to Sun (km) Sun 1 392 000 Mercury 4 878 57.9 106 Venus 12 180 108.3 106 Earth 12 756 149.7 106 Marte 6 760 228.1 106 Jupiter 142 800 778.7 106 Saturn 120 000 1 430.1 106 Uranus 50 000 2 876.5 106 Neptune 49 000 4 506.6 106 Table 1: Data of the Solar System bodies In all cases, the main goal of the model is to make the data understandable. -
Arxiv:0705.4139V2 [Astro-Ph] 14 Dec 2007 the Bulk Motion of the Local Sheet Away from the Local Void
Our Peculiar Motion Away from the Local Void R. Brent Tully, Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 and Edward J. Shaya University of Maryland, Astronomy Department, College Park, MD 20743 and Igor D. Karachentsev. Special Astrophysical Observatory, Nizhnij Arkhyz, Karachaevo-Cherkessia, Russia and H´el`eneM. Courtois, Dale D. Kocevski, and Luca Rizzi Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 and Alan Peel University of Maryland, Astronomy Department, College Park, MD 20743 ABSTRACT The peculiar velocity of the Local Group of galaxies manifested in the Cosmic Microwave Background dipole is found to decompose into three dominant components. The three compo- nents are clearly separated because they arise on distinct spatial scales and are fortuitously almost orthogonal in their influences. The nearest, which is distinguished by a velocity discontinuity at ∼ 7 Mpc, arises from the evacuation of the Local Void. We lie in the Local Sheet that bounds the void. Random motions within the Local Sheet are small and we advocate a reference frame with respect to the Local Sheet in preference to the Local Group. Our Galaxy participates in arXiv:0705.4139v2 [astro-ph] 14 Dec 2007 the bulk motion of the Local Sheet away from the Local Void. The component of our motion on an intermediate scale is attributed to the Virgo Cluster and its surroundings, 17 Mpc away. The third and largest component is an attraction on scales larger than 3000 km s−1 and centered near the direction of the Centaurus Cluster. The amplitudes of the three components are 259, 185, and 455 km s−1, respectively, adding collectively to 631 km s−1 in the reference frame of the Local Sheet. -
A Planetary Companion to the Nearby M4 Dwarf, Gliese
A Planetary Companion to the Nearby M4 Dwarf, Gliese 876 1 Geoffrey W. Marcy2, R. Paul Butler,3, Steven S. Vogt4, Debra Fischer2, Jack J. Lissauer5 Received ; accepted Submitted to Astrophysical Journal Letters 1 arXiv:astro-ph/9807307v1 29 Jul 1998 Based on observations obtained at Lick Observatory, which is operated by the University of California, and on observations obtained at the W.M. Keck Observatory, which is operated jointly by the University of California and the California Institute of Technology. 2Department of Physics and Astronomy, San Francisco, CA, USA 94132 and at Department of Astronomy, University of California, Berkeley, CA USA 94720 3Anglo–Australian Observatory, PO Box 296, NSW 2121 Epping, Australia 4UCO/Lick Observatory, University of California at Santa Cruz, Santa Cruz, CA, 95064 5NASA/Ames Research Center, NASA/Ames Research Center, MS245-3, Moffett Field, CA 94035 –2– ABSTRACT Doppler measurements of the M4 dwarf star, Gliese 876, taken at both Lick and Keck Observatory reveal periodic, Keplerian velocity variations with a period of 61 days. The orbital fit implies that the companion has a mass of, M = 2.1 MJUP/ sin i, an orbital eccentricity of, e = 0.27 0.03, and a semimajor ± axis of, a = 0.21 AU. The planet is the first found around an M dwarf, and was drawn from a survey of 24 such stars at Lick Observatory. It is the closest extrasolar planet yet found, providing opportunities for follow–up detection. The presence of a giant planet on a non-circular orbit, 0.2 AU from a 1/3 M⊙ star, presents a challenge to planet formation theory. -
The Stability of Ultra-Compact Planetary Systems
A&A 516, A82 (2010) Astronomy DOI: 10.1051/0004-6361/200912698 & c ESO 2010 Astrophysics The stability of ultra-compact planetary systems B. Funk1, G. Wuchterl2,R.Schwarz1,3, E. Pilat-Lohinger3, and S. Eggl3 1 Department of Astronomy, Eötvös Loránd University, Pázmány Péter Sétány 1/A, 1117 Budapest, Hungary e-mail: [email protected] 2 Thüringer Landessternwarte, Sternwarte 5, 07778 Tautenburg, Germany e-mail: [email protected] 3 Institute for Astronomy, University of Vienna, Türkenschanzstrasse 17, 1180 Vienna, Austria e-mail: [schwarz;lohinger;eggl]@astro.univie.ac.at Received 15 June 2009 / Accepted 15 March 2010 ABSTRACT Aims. We investigate the dynamical stability of compact planetary systems in the CoRoT discovery space, i.e., with orbital periods of less than 50 days, including a detailed study of the stability of systems, which are spaced according to Hill’s criteria. Methods. The innermost fictitious planet was placed close to the Roche limit from the star (MStar = 1 MSun) and all other fictitious planets are lined up according to Hill’s criteria up to a distance of 0.26 AU, which corresponds to a 50 day period for a Sun-massed star. For the masses of the fictitious planets, we chose a range of 0.33–17 mEarth, where in each simulation all fictitious planets have the same mass. Additionally, we tested the influence of both the semi-major axis of the innermost planet and of the number of planets. In a next step we also included a gas giant in our calculations, which perturbs the inner ones and investigated their stability. -
Abhören Von Funksignalen Durch Extraterrestrische Lebensformen
Abhören von Funksignalen durch extraterrestrische Lebensformen Diplomarbeit zur Erlangung des akademischen Grades eines Magisters der Naturwissenschaften an der Karl-Franzens-Universität Graz vorgelegt von Andreas Franz KLAUSNER am Institut für Physik Begutachter: Univ.-Prof. Dr.phil Arnold Hanslmeier Graz, 2018 Eidesstattliche Erklärung Ich erkläre eidesstattlich, dass ich die vorliegende Arbeit selbstständig und ohne fremde Hilfe verfasst, andere als die angegebenen Quellen nicht benutzt und die den Quellen wörtlich oder inhaltlich entnommenen Stellen als solche kenntlich gemacht habe. Die Arbeit wurde bisher in gleicher oder ähnlicher Form keiner anderen inländischen oder ausländischen Prüfungsbehörde vorgelegt und auch noch nicht veröffentlicht. Die vorliegende Fassung entspricht der eingereichten elektronischen Version. Datum: _________________ Unterschrift: _________________________ Inhaltsverzeichnis Forschungsfragen .................................................................................................................................... V 1. Einleitung ......................................................................................................................................... 1 2. Ausbreitung elektromagnetischer Wellen ...................................................................................... 2 2.1 Geschwindigkeit von elektromagnetischen Wellen ............................................................ 4 2.2 Energietransport von elektromagnetischen Wellen .......................................................... -
The TRAPPIST-1 JWST Community Initiative
Bulletin of the AAS • Vol. 52, Issue 2 The TRAPPIST-1 JWST Community Initiative Michaël Gillon1, Victoria Meadows2, Eric Agol2, Adam J. Burgasser3, Drake Deming4, René Doyon5, Jonathan Fortney6, Laura Kreidberg7, James Owen8, Franck Selsis9, Julien de Wit10, Jacob Lustig-Yaeger11, Benjamin V. Rackham10 1Astrobiology Research Unit, University of Liège, Belgium, 2Department of Astronomy, University of Washington, USA, 3Department of Physics, University of California San Diego, USA, 4Department of Astronomy, University of Maryland at College Park, USA, 5Institute for Research in Exoplanets, University of Montreal, Canada, 6Other Worlds Laboratory, University of California Santa Cruz, USA, 7Center for Astrophysics | Harvard and Smithsonian, USA, 8Department of Physics, Imperial College London, United Kingdom, 9Laboratoire d’Astrophysique de Bordeaux, University of Bordeaux, France, 10Department of Earth, Atmospheric, and Planetary Sciences, MIT, USA, 11Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA Published on: Dec 02, 2020 DOI: 10.3847/25c2cfeb.afbf0205 License: Creative Commons Attribution 4.0 International License (CC-BY 4.0) Bulletin of the AAS • Vol. 52, Issue 2 The TRAPPIST-1 JWST Community Initiative ABSTRACT The upcoming launch of the James Webb Space Telescope (JWST) combined with the unique features of the TRAPPIST-1 planetary system should enable the young field of exoplanetology to enter into the realm of temperate Earth-sized worlds. Indeed, the proximity of the system (12pc) and the small size (0.12 R ) -
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A&A 577, A144 (2015) Astronomy DOI: 10.1051/0004-6361/201526054 & c ESO 2015 Astrophysics A graph of dark energy significance on different spatial and mass scales (Research Note) P. Teerikorpi1, P. Heinämäki1,P.Nurmi1,A.D.Chernin2, M. Einasto3,M.Valtonen1, and G. Byrd4 1 Tuorla Observatory, Department of Physics and Astronomy, University of Turku, 21500 Piikkiö, Finland e-mail: [email protected] 2 Sternberg Astronomical Institute, Moscow University, 119899 Moscow, Russia 3 Tartu Observatory, 61602 Tõravere, Estonia 4 University of Alabama, Tuscaloosa, AL 35487-0324, USA Received 9 March 2015 / Accepted 21 March 2015 ABSTRACT Context. The current cosmological paradigm sees the formation and evolution of the cosmic large-scale structure as governed by the gravitational attraction of dark matter (DM) and the repulsion of dark energy (DE). Aims. We characterize the relative importance of uniform and constant dark energy, as given by the Λ term in the standard ΛCDM cos- mology, in galaxy systems of different scales from groups to superclusters. Methods. An instructive “Λ significance graph” is introduced where the matter-DE density ratio ρM/ρΛ for different galaxy systems is plotted against the radius R. This presents gravitation- and DE-dominated regions and directly shows the zero velocity radius, the zero-gravity radius, and the Einstein-Straus radius for any fixed value of mass. Results. Example galaxy groups and clusters from the local universe illustrate the use of the Λ significance graph. These are generally located deep in the gravity-dominated region ρM/ρΛ > 2, and are virialized. Extended clusters and the main bodies of superclusters can reach down near the borderline between gravity-dominated and DE-dominated regions ρM/ρΛ = 2.