Wide Field Aperture Synthesis Radio Astronomy
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Radio Astronomy & Radio Telescopes
Radio Astronomy & Radio Telescopes Tasso Tzioumis ([email protected]) Australia Telescope National Facility (ATNF) sms2020, Stellenbosch 2-6 March 2020 CSIRO ASTRONOMY AND SPACE SCIENCE Radio Astronomy – ITU definition 1.13 radio astronomy: Astronomy based on the reception of radio waves of cosmic origin. 1.5 radio waves or hertzian waves: Electromagnetic waves of frequencies arbitrarily lower than 3 000 GHz, propagated in space without artificial guide. • Astronomy covers the whole electromagnetic spectrum • Radio astronomy is the “low energy” part of the spectrum é 3 000 GHz Radioastronomy & Radio telescopes | Tasso Tzioumis Radio Astronomy “special” characteristics Technical challenges • Very faint signals – measured in 10-26 W/m2/Hz (-260 dBW) • “Power collected by all radiotelescopes since the start of radio astronomy would light a 1W bulb for less than 1 second” • à Need “sensitivity” i.e. large antennas and/or arrays of many antennas • à Very susceptible to intereference • Celestial structures at all scales: from very large to very small • à Need “spatial resolution” i.e. ability to see the details at all scales • à Need large antennas and/or arrays of many antennas • Astronomical events at all timescales(from < 1ms to > millions years) & and at all spectral resolutions (from < 1 Hz to GHz) • à Need very high time and frequency resolution • à Sensitive telescopes and arrays & extreme technical challenges Radioastronomy & Radio telescopes | Tasso Tzioumis Radio Astronomy “special” characteristics Scientific challenges • Radio -
Educator's Guide: Orion
Legends of the Night Sky Orion Educator’s Guide Grades K - 8 Written By: Dr. Phil Wymer, Ph.D. & Art Klinger Legends of the Night Sky: Orion Educator’s Guide Table of Contents Introduction………………………………………………………………....3 Constellations; General Overview……………………………………..4 Orion…………………………………………………………………………..22 Scorpius……………………………………………………………………….36 Canis Major…………………………………………………………………..45 Canis Minor…………………………………………………………………..52 Lesson Plans………………………………………………………………….56 Coloring Book…………………………………………………………………….….57 Hand Angles……………………………………………………………………….…64 Constellation Research..…………………………………………………….……71 When and Where to View Orion…………………………………….……..…77 Angles For Locating Orion..…………………………………………...……….78 Overhead Projector Punch Out of Orion……………………………………82 Where on Earth is: Thrace, Lemnos, and Crete?.............................83 Appendix………………………………………………………………………86 Copyright©2003, Audio Visual Imagineering, Inc. 2 Legends of the Night Sky: Orion Educator’s Guide Introduction It is our belief that “Legends of the Night sky: Orion” is the best multi-grade (K – 8), multi-disciplinary education package on the market today. It consists of a humorous 24-minute show and educator’s package. The Orion Educator’s Guide is designed for Planetarians, Teachers, and parents. The information is researched, organized, and laid out so that the educator need not spend hours coming up with lesson plans or labs. This has already been accomplished by certified educators. The guide is written to alleviate the fear of space and the night sky (that many elementary and middle school teachers have) when it comes to that section of the science lesson plan. It is an excellent tool that allows the parents to be a part of the learning experience. The guide is devised in such a way that there are plenty of visuals to assist the educator and student in finding the Winter constellations. -
Design Radiator Catalogue
January 2019 Offers Beauty And Functionality Design Stay Classy Radiator Be Extraordinary Catalogue MORE THAN A RADIATOR AESTHETICALLY STRONG DIFFERENT IN STYLE 2 warmhaus.co.uk Contents Chrome Radiators p. 5 White & Anthracite Radiators p. 29 Multi Column Radiators p. 55 Myth Atmosphere Moonlight - Arcadia - Andromeda - Artemis - Atlantis - Aquila - Celine - Camelot - Carina - Luna - Nysa - Draco - Mika - Dinas - Circinus - Selena - Lyonesse - Columba - Shiva - Meropis - Crux - Chandra - Brittia - Hercules - Hawaiki - Mensa Traditional Radiators p. 65 - Oasis - Orion Heritage - Phoenix Stainless Steel Radiators p. 19 - Pyxis - Aztec Impulse - Vela - Inca - Tucana - Roma - Storm - Aquarius - Maya - Hurricane - Aries - Lydia - Thunder - Lyra - Kush - Swirl - Dorado - Tuwana - Flash - Gemini - Aksum - Whirlwind - Leo - Hittite - Tornado - Hydra - Pisces - Pictor - Scorpius - Taurus - Virgo - Cepheus warmhaus.co.uk 3 CHROME RADIATORS 4 warmhaus.co.uk Myth Warmhaus Myth Series offers you the opportunity to live with legends of the past. warmhaus.co.uk 5 CHROME RADIATORS 6 warmhaus.co.uk MYTH ARCADIA Product Code C5 Profile: Square Bar: Square PRODUCT HEIGHT WIDTH C/C W/C PRODUCT BTU/DT60 WATT CODE (mm) (mm) (mm) (mm) Arcadia C5 600 300 260 55~70 675 198 Arcadia C5 600 400 360 55~70 829 243 Arcadia C5 600 500 460 55~70 982 288 Arcadia C5 600 600 560 55~70 1136 333 Arcadia C5 800 300 260 55~70 939 275 Arcadia C5 800 400 360 55~70 1162 341 Arcadia C5 800 500 460 55~70 1383 406 Arcadia C5 800 600 560 55~70 1607 471 Arcadia C5 1000 300 260 55~70 -
Interferometry and Aperture Synthesis in Order to Understand the Re
Summer Student Lecture Notes INTERFEROMETRY AND APERTURE SYNTHESIS Bruce Balick July 1973 The following pages are reprinted (with corrections) from Balick, B. 1972, thesis (Cornell University) CHAPTER II INTERFEROMETRY AND APERTURE SYNTHESIS Electromagnetic radiation is a wave phenomena, consequently in- struments used to observe this radiation are subject to diffraction limi- tations on their resolution. The angular limit, A, is given approxi- mately by AS6 D/A, where D is the aperture dimension and X is the obscwrving wavelcngth; for radio work - _____A - 140 B/cm) min -arc [D/feet] Thus the 300-foot telescope has a maximum resolution of 6' .arc at XAll cm, whereas a 10-cm aperture optical telescope has a diffraction limit of 1" are at optical wavelengths. (The same high resolution would require ap- ertures 1-1000 km in diameter at radio wavelengths.) To obtain high resolution at radio wavelengths, partially fill- ed apertures of large diameter can be synthesized. For this, two tele- scopes separated by a baseline B can be used to simulate the response of a nearly circular annulus of diameter IB. The telescope pair is con- figured in such a manner that it is best described as an interferometer in the ordinary optical sense. By moving the telescopes to obtain inter- ferometers of different spacings, annuli of different sizes can be simu- lated. The results obtained on the various spacings can be added appropriately to synthesize the response of a single telescope of very large diameter, and thereby yield maps of high resolution. For example, the interferometer of the National Radio Astronomy Observatory (NRAO) can 10 S. -
What Is CHEOPS?
Swiss and ESA satellite CHEOPS launching soon! CHEOPS will be launching into space on the 17th of December! You may be wondering: what is CHEOPS? CHEOPS stands for CHaracterising ExOPlanet Satellite. Its goal is to study transits of already-known exoplanets to gain more knowledge about them. What type of information are we looking for? Scientists want to know detailed information about planets outside our Solar System, such as the mass, planet size, and density, which will in turn help to figure out the composition of these exoplanets. Studying exoplanet composition and their atmospheres is important especially for astrobiology. A planet’s chemical composition can affect its habitability for life as we know it. Scientists usually look for biosignatures such as the presence of methane or oxygen in the planet’s atmosphere, which could indicate presence of past or present life. Artist’s impression of CHEOPS. Credits: ESA / ATG medialab. The major contributors CHEOPS is a collaboration between ESA and the Swiss Space Office. The mission was proposed and is now headed by Prof. Willy Benz, from the University of Bern, which houses the mission’s consortium. The science operations consortium is at the University of Geneva, where they have many collaborators, such as the Swiss Space Center at EPFL. As it is an ESA endeavour, many other European institutions are also contributing to the mission. For example, the mission operations consortium is located in Torrejón de Ardoz, Spain. The launch The satellite has already been shipped to Kourou, French Guiana, where it will be launched by the ESA spaceport. -
The Argo Navis Constellation
THE ARGO NAVIS CONSTELLATION At the last meeting we talked about the constellation around the South Pole, and how in the olden days there used to be a large ship there that has since been subdivided into the current constellations. I could not then recall the names of the constellations, but remembered that we talked about this subject at one of the early meetings, and now found it in September 2011. In line with my often stated definition of Astronomy, and how it seems to include virtually all the other Philosophy subjects: History, Science, Physics, Biology, Language, Cosmology and Mythology, lets go to mythology and re- tell the story behind the Argo Constellation. Argo Navis (or simply Argo) used to be a very large constellation in the southern sky. It represented the ship The Argo Navis ship with the Argonauts on board used by the Argonauts in Greek mythology who, in the years before the Trojan War, accompanied Jason to Colchis (modern day Georgia) in his quest to find the Golden Fleece. The ship was named after its builder, Argus. Argo is the only one of the 48 constellations listed by the 2nd century astronomer Ptolemy that is no longer officially recognised as a constellation. In 1752, the French astronomer Nicolas Louis de Lacaille subdivided it into Carina (the keel, or the hull, of the ship), Puppis (the poop deck), and Vela (the sails). The constellation Pyxis (the mariner's compass) occupies an area which in antiquity was considered part of Argo's mast (called Malus). The story goes that, when Jason was 20 years old, an oracle ordered him to head to the Iolcan court (modern city of Volos) where king Pelias was presiding over a sacrifice to Poseidon with several neighbouring kings in attendance. -
Cross-Correlator Implementations Enabling Aperture Synthesis for Geostationary-Based Remote Sensing
THESIS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY Cross-Correlator Implementations Enabling Aperture Synthesis for Geostationary-Based Remote Sensing ERIK RYMAN Division of Computer Engineering Department of Computer Science and Engineering CHALMERS UNIVERSITY OF TECHNOLOGY Göteborg, Sweden 2018 Cross-Correlator Implementations Enabling Aperture Synthesis for Geostationary-Based Remote Sensing Erik Ryman ISBN 978-91-7597-751-5 Copyright © Erik Ryman, 2018. Doktorsavhandlingar vid Chalmers tekniska högskola Ny serie Nr 4432 ISSN 0346-718X Technical report No. 156D Department of Computer Science and Engineering VLSI Research Group Department of Computer Science and Engineering Chalmers University of Technology SE-412 96 GÖTEBORG, Sweden Phone: +46 (0)31-772 10 00 Author e-mail: [email protected] Cover: A 64-channel cross-correlator unit, including chip photos of digital correlator and analog-to-digital converter. Printed by Chalmers Reproservice Göteborg, Sweden 2018 Cross-Correlator Implementations Enabling Aperture Synthesis for Geostationary-Based Remote Sensing Erik Ryman Department of Computer Science and Engineering, Chalmers University of Technology ABSTRACT An ever-increasing demand for weather prediction and high climate modelling ac- curacy drives the need for better atmospheric data collection. These demands in- clude better spatial and temporal coverage of mainly humidity and temperature distributions in the atmosphere. A new type of remote sensing satellite technol- ogy is emerging, originating in the field of radio astronomy where telescope aper- ture upscaling could not keep up with the increasing demand for higher resolution. Aperture synthesis imaging takes an array of receivers and emulates apertures ex- tending way beyond what is possible with any single antenna. In the field of Earth remote sensing, the same idea could be used to construct satellites observing in the microwave region at a high resolution with foldable antenna arrays. -
Exoplanet Tool Kit
Exoplanet Tool Kit New Mexico Super Computing Challenge Final Report April 5, 2011 Team 35 Desert Academy Team Members Chris Brown Isaac Fischer Teacher Jocelyn Comstock Mentors Henry Brown Prakash Bhakta Table of Contents Executive Summary ................................................................................................ 2 Background ............................................................................................................ 3 Astrophysics .............................................................................................. 3 Definition and Origin of Extroplanets ....................................................... 4 Methods of Detection ............................................................................... 4 Project .................................................................................................................. 6 Methodology............................................................................................. 6 Data Results .............................................................................................. 7 Conclusion ............................................................................................................ 10 Future Study ......................................................................................................... 11 Acknowledgements.............................................................................................. 12 References .......................................................................................................... -
Book of Abstracts
Dissecting the Universe - Workshop on Results from High-Resolution VLBI Monday 30 November 2015 - Wednesday 02 December 2015 Max-Planck-Institut für Radioastronomie, Bonn, Germany Book of Abstracts Contents GMVA Observations of M87 and Status Report of the GLT Project . 1 Water megamasers at high resolution . 1 Millimeter VLBI Observations of the Twin-Jet-System in NGC1052 . 1 First 3mm-VLBI imaging of the two-sided jet in Cygnus A: zooming into the launching region . 2 New insight into AGN-jets: they are alive! . 2 The connection between the mm VLBI jet and the gamma-ray emission in the blazar CTA102 and the radio galaxy 3C120 . 2 New Developments with the Event Horizon Telescope . 3 Dissecting TeV blazars: Space VLBI study of the BL Lac source Markarian 501 . 3 VLBI Studies of Star Forming Regions using Molecular Masers . 4 The farthest view with overterrestrial baselines . 4 Probing the innermost regions of AGN jets and their magnetic fields with RadioAstron 4 What has VLBI at the highest resolutions taught us about the VLBI "core"? . 5 The most compact H2O maser spots and their locations in W3 IRS5 . 5 A physical model for the radio and GeV emission from the microquasar LS I +61◦303 6 Detection and Implications of Horizon-Scale Polarization in Sgr A* . 7 The Discovery and Implications of Refractive Substructure for VLBI at the Highest Angular Resolutions . 7 Microarcsecond Structure of the Parsec Scale Jet of the Quasar 3C454.3 . 7 Jets from Water-Disk-Megamaser Galaxies . 8 Unlocking the secrets of PKS 1502+106. Synergies between mm-VLBI and single-dish monitoring . -
These Sky Maps Were Made Using the Freeware UNIX Program "Starchart", from Alan Paeth and Craig Counterman, with Some Postprocessing by Stuart Levy
These sky maps were made using the freeware UNIX program "starchart", from Alan Paeth and Craig Counterman, with some postprocessing by Stuart Levy. You’re free to use them however you wish. There are five equatorial maps: three covering the equatorial strip from declination −60 to +60 degrees, corresponding roughly to the evening sky in northern winter (eq1), spring (eq2), and summer/autumn (eq3), plus maps covering the north and south polar areas to declination about +/− 25 degrees. Grid lines are drawn at every 15 degrees of declination, and every hour (= 15 degrees at the equator) of right ascension. The equatorial−strip maps use a simple rectangular projection; this shows constellations near the equator with their true shape, but those at declination +/− 30 degrees are stretched horizontally by about 15%, and those at the extreme 60−degree edge are plotted twice as wide as you’ll see them on the sky. The sinusoidal curve spanning the equatorial strip is, of course, the Ecliptic −− the path of the Sun (and approximately that of the planets) through the sky. The polar maps are plotted with stereographic projection. This preserves shapes of small constellations, but enlarges them as they get farther from the pole; at declination 45 degrees they’re about 17% oversized, and at the extreme 25−degree edge about 40% too large. These charts plot stars down to magnitude 5, along with a few of the brighter deep−sky objects −− mostly star clusters and nebulae. Many stars are labelled with their Bayer Greek−letter names. Also here are similarly−plotted maps, based on galactic coordinates. -
NL#135 May/June
May/June 2007 Issue 135 A Publication for the members of the American Astronomical Society 3 IOP to Publish President’s Column AAS Journals J. Craig Wheeler, [email protected] Whew! A lot has happened! 5 Member Deaths First, my congratulations to John Huchra who was elected to be the next President of the Society. John will formally become President-Elect at the meeting in Hawaii. He will then take over as President at the meeting in St. Louis in June of 2008 and I will serve as Past-President until the 6 Pasadena meeting in June of 2009. We have hired a consultant to lead a one-day Council retreat before the Hawaii meeting to guide the Council toward a more strategic outlook for the Society. Seattle Meeting John has generously agreed to join that effort. I know he will put his energy, intellect, and experience Highlights behind the health and future of the Society. We had a short, intense, and very professional process to issue a Request for Proposals (RFP) to 10 publish the Astrophysical Journal and the Astronomical Journal, to evaluate the proposals, and Award Winners to select a vendor. We are very pleased that the IOP Publishing will be the new publisher of our cherished and prestigious journals and are very optimistic that our new partnership will lead to in Seattle a necessary and valuable evolution of what it means to publish science journals in the globally- connected electronic age. 11 The complex RFP defining our journals and our aspirations for them was put together by a team International consisting of AAS representatives and outside independent consultants. -
A Compendium of Distances to Molecular Clouds in the Star Formation Handbook?,?? Catherine Zucker1, Joshua S
A&A 633, A51 (2020) Astronomy https://doi.org/10.1051/0004-6361/201936145 & c ESO 2020 Astrophysics A compendium of distances to molecular clouds in the Star Formation Handbook?,?? Catherine Zucker1, Joshua S. Speagle1, Edward F. Schlafly2, Gregory M. Green3, Douglas P. Finkbeiner1, Alyssa Goodman1,5, and João Alves4,5 1 Center for Astrophysics | Harvard & Smithsonian, 60 Garden St., Cambridge, MA 02138, USA e-mail: [email protected], [email protected] 2 Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, CA 94720, USA 3 Kavli Institute for Particle Astrophysics and Cosmology, Physics and Astrophysics Building, 452 Lomita Mall, Stanford, CA 94305, USA 4 University of Vienna, Department of Astrophysics, Türkenschanzstraße 17, 1180 Vienna, Austria 5 Radcliffe Institute for Advanced Study, Harvard University, 10 Garden St, Cambridge, MA 02138, USA Received 21 June 2019 / Accepted 12 August 2019 ABSTRACT Accurate distances to local molecular clouds are critical for understanding the star and planet formation process, yet distance mea- surements are often obtained inhomogeneously on a cloud-by-cloud basis. We have recently developed a method that combines stellar photometric data with Gaia DR2 parallax measurements in a Bayesian framework to infer the distances of nearby dust clouds to a typical accuracy of ∼5%. After refining the technique to target lower latitudes and incorporating deep optical data from DECam in the southern Galactic plane, we have derived a catalog of distances to molecular clouds in Reipurth (2008, Star Formation Handbook, Vols. I and II) which contains a large fraction of the molecular material in the solar neighborhood. Comparison with distances derived from maser parallax measurements towards the same clouds shows our method produces consistent distances with .10% scatter for clouds across our entire distance spectrum (150 pc−2.5 kpc).