Conventional Parabolic Single Dishes the Green Bank Telescope
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Jodrell Bank Observatory
UK Tentative List of Potential Sites for World Heritage Nomination: Application form Please save the application to your computer, fill in and email to: [email protected] The application form should be completed using the boxes provided under each question, and, where possible, within the word limit indicated. Please read the Information Sheets before completing the application form. It is also essential to refer to the accompanying Guidance Note for help with each question, and to the relevant paragraphs of UNESCO’s Operational Guidelines for the Implementation of the World Heritage Convention, (OG) available at: http://whc.unesco.org/en/guidelines Applicants should provide only the information requested at this stage. Further information may be sought in due course. (1) Name of Proposed World Heritage Site Jodrell Bank Observatory (2) Geographical Location Name of country/region United Kingdom Grid reference to centre of site SJ 798708 Please enclose a map preferably A4-size, a plan of the site, and 6 photographs, preferably electronically. page 1 (3) Type of Site Please indicate category: Natural Cultural Mixed Cultural Landscape (4) Description Please provide a brief description of the proposed site, including the physical characteristics. 200 words The Jodrell Bank Observatory, which is part of the University of Manchester’s School of Physics and Astronomy, is dominated by the monumental Lovell Telescope, the first large fully steerable radio telescope in the world - which still operates as the 3rd largest on the planet. The telescope, which is a Grade 1 listed structure, is 76m in diameter and stands 89m high. Despite its age (53 years in 2010), it is now more powerful than ever and remains at the forefront of Astrophysics research, working 24 hours a day, 365 days a year to observe distant galaxies and objects such as Pulsars and Quasars, far out across the Universe. -
Mirrors Or Lenses) Can Produce an Image of the Object by 4.2 Mirrors Redirecting the Light
Object-Image • A physical object is usually observed by reflected light that diverges from the object. • An optical system (mirrors or lenses) can produce an image of the object by 4.2 Mirrors redirecting the light. • Images – Real Image • Image formation by mirrors – Virtual Image • Plane mirror • Curved mirrors. Real Image Virtual Image Optical System ing diverging erg converging diverging diverging div Object Object real Image Optical System virtual Image Light appears to come from the virtual image but does not Light passes through the real image pass through the virtual image Film at the position of the real image is exposed. Film at the position of the virtual image is not exposed. Each point on the image can be determined Image formed by a plane mirror. by tracing 2 rays from the object. B p q B’ Object Image The virtual image is formed directly behind the object image mirror. Light does not A pass through A’ the image mirror A virtual image is formed by a plane mirror at a distance q behind the mirror. q = -p 1 A mirror reverses front and back Parabolic Mirrors Optic Axis object mirror image mirror The mirror image is different from the object. The z direction is reversed in the mirror image. Parallel rays reflected by a parabolic mirror are focused at a point, called the Focal Point located on the optic axis. Your right hand is the mirror image of your left hand. Parabolic Reflector Spherical mirrors • Spherical mirrors can be used to form images • Spherical mirrors are much easier to fabricate than parabolic mirrors • A spherical mirror is an approximation of a parabolic mirror for small curvatures. -
50 Years of the Lovell Telescope Transcript
50 years of the Lovell telescope Transcript Date: Wednesday, 5 December 2007 - 12:00AM 50 YEARS OF THE LOVELL TELESCOPE Professor Ian Morison The Early days at Jodrell Bank In late 1945 Dr Bernard Lovell (as he then was) returned to Manchester University after working on the development of radar during the war years. His aim was to continue his researches into cosmic rays - highly energetic particles that enter the Earth's atmosphere from outer space. He had the idea that sporadic echoes sometimes received by military radars might be the result of cosmic rays entering the atmosphere and thus radar observations might provide a new way to continue his researches. Radar observations were not practical in the centre of Manchester so he took his ex-army radar system out to the University's Botanical Grounds at Jodrell Bank, some 20 miles to the south. By the middle of December 1945, the system was operating and his team was soon able to prove that the echoes were coming not from cosmic rays but from ionized meteor trails left behind when small particles, released from comets, are burnt up in the upper atmosphere of the Earth. Radar Antenna in the Botany Grounds. The Jodrell Bank Experimental Station. The observations continued and, to house the expanding staff and equipment, the Jodrell Bank Experimental Station was built in the field next to the Botanic Grounds. Lovell realised that a much more sensitive radio telescope would be required to detect cosmic rays and so, in 1947, the researchers built a large parabolic reflector, 66-m across, pointing upwards to observe the sky passing overhead. -
The Merlin - Phase 2
Radio Interferometry: Theory, Techniques and Applications, 381 IAU Coll. 131, ASP Conference Series, Vol. 19, 1991, T.J. Comwell and R.A. Perley (eds.) THE MERLIN - PHASE 2 P.N. WILKINSON University of Manchester, Nuffield Radio Astronomy Laboratories, Jodrell Bank, Macclesfield, Cheshire, SKll 9DL, United Kingdom ABSTRACT The Jodrell Bank MERLIN is currently being upgraded to produce higher sensitivity and higher resolving power. The major capital item has been a new 32m telescope located at MRAO Cambridge which will operate to at least 50 GHz. A brief outline of the upgraded MERLIN and its performance is given. INTRODUCTION The MERLIN (Multi-Element Radio-Linked Interferometer Network), based at Jodrell Bank, was conceived in the mid-1970s and first became operational in 1980. It was a bold concept; no one had made a real-time long-baseline interferometer array with phase-stable local oscillator links before. Six remotely operated telescopes, controlled via telephone lines, are linked to a control computer at Jodrell Bank. The rf signals are transmitted to Jodrell via commercial multi-hop microwave links operating at 7.5 GHz. The local oscillators are coherently slaved to a master oscillator via go-and- return links operating at L-band, the change in the link path-length being taken out in software. This single-frequency L-band link can transfer phase to the equivalent of < 1 picosec (< 0.3 mm of path length) on timescales longer than a few seconds. A detailed description of the MERLIN system has been given by Thomasson (1986). The MERLIN has provided the UK with a unique astronomical facility, one which has made important contributions to extragalactic radio source and OH maser studies. -
The Lovell Telescope … Through Its Surfaces Simon Garrington, JBO/University of Manchester
The Lovell Telescope … through its surfaces Simon Garrington, JBO/University of Manchester • Original design & redesign: 1950-1957 • Radical modification & new surface: 1971 • Replacement of surface: 2001 • Replacement of original Picture A. Holloway surface: 2018 • Other consequences: foundations O1 Original MkI proposal and changes • Concept & proposals: 1950-1 • Lovell-Husband Sep 1949 • Radio Astronomy Cttee 1950 • rail track; towers, cradle, 4-inch mesh • 2-inch mesh/5-in profile by 20 Mar 1951 submission • Design changes • 21cm line discovered (Ewen 25 Mar 1951) • Inner 100’ mesh 1x2-in ‘at no cost’ ? Sep 1952 • Interest from Air Ministry: 10cm radar • March 1954: 3/4-in mesh -> stronger cradle … but Air Ministry step back O2 Original MkI proposal and changes • Concept & proposals: 1950-1 • Lovell-Husband Sep 1949 • Radio Astronomy Cttee 1950 • rail track; towers, cradle, 4-inch mesh • 2-inch mesh/5-in profile by 20 Mar 1951 submission • Design changes • 21cm line discovered (Ewen 25 Mar 1951) • Inner 100’ mesh 1x2-in ‘at no cost’ ? Sep 1952 • Interest from Air Ministry: 10cm radar • March 1954: 3/4-in mesh -> stronger cradle … but Air Ministry step back O3 Original MkI proposal and changes • Concept & proposals: 1950-1 • Lovell-Husband Sep 1949 • Radio Astronomy Cttee 1950 • rail track; towers, cradle, 4-inch mesh • 2-inch mesh/5-in profile by 20 Mar 1951 submission • Design changes • 21cm line discovered (Ewen 25 Mar 1951) • Inner 100’ mesh 1x2-in ‘at no cost’ ? Sep 1952 • Interest from Air Ministry: 10cm radar • March 1954: 3/4-in -
Dynamics of the Arecibo Radio Telescope
DYNAMICS OF THE ARECIBO RADIO TELESCOPE Ramy Rashad 110030106 Department of Mechanical Engineering McGill University Montreal, Quebec, Canada February 2005 Under the supervision of Professor Meyer Nahon Abstract The following thesis presents a computer and mathematical model of the dynamics of the tethered subsystem of the Arecibo Radio Telescope. The computer and mathematical model for this part of the Arecibo Radio Telescope involves the study of the dynamic equations governing the motion of the system. It is developed in its various components; the cables, towers, and platform are each modeled in succession. The cable, wind, and numerical integration models stem from an earlier version of a dynamics model created for a different radio telescope; the Large Adaptive Reflector (LAR) system. The study begins by converting the cable model of the LAR system to the configuration required for the Arecibo Radio Telescope. The cable model uses a lumped mass approach in which the cables are discretized into a number of cable elements. The tower motion is modeled by evaluating the combined effective stiffness of the towers and their supporting backstay cables. A drag model of the triangular truss platform is then introduced and the rotational equations of motion of the platform as a rigid body are considered. The translational and rotational governing equations of motion, once developed, present a set of coupled non-linear differential equations of motion which are integrated numerically using a fourth-order Runge-Kutta integration scheme. In this manner, the motion of the system is observed over time. A set of performance metrics of the Arecibo Radio Telescope is defined and these metrics are evaluated under a variety of wind speeds, directions, and turbulent conditions. -
Istituto Di Radioastronomia Inaf
ISTITUTO DI RADIOASTRONOMIA INAF STATUS REPORT October 2007 http://www.ira.inaf.it/ Chapter 1. STRUCTURE AND ORGANIZATION The Istituto di Radioastronomia (IRA) is presently the only INAF structure with divisions distributed over the national territory. Such an organization came about because IRA was originally a part of the National Council of Research (CNR), which imposed the first of its own reforms in 2001. The transition from CNR to INAF began in 2004 and was completed on January 1st , 2005. The Institute has its headquarters in Bologna in the CNR campus area, and two divisions in Firenze and Noto. The Medicina station belongs to the Bologna headquarters. A fourth division is foreseen in Cagliari at the Sardinia Radiotelescope site. The IRA operates 3 radio telescopes: the Northern Cross Radio Telescope (Medicina), and two 32-m dishes (Medicina and Noto), which are used primarily for Very Long Baseline Interferometry (VLBI) observations. The IRA leads the construction of the Sardinia Radio Telescope (SRT), a 64-m dish of new design. This is one of the INAF large projects nowadays. The aims of the Institute comprise: - the pursuit of excellence in many research areas ranging from observational radio astronomy, both galactic and extragalactic, to cosmology, to geodesy and Earth studies; - the design and management of the Italian radio astronomical facilities; - the design and fabrication of instrumentation operating in bands from radio to infrared and visible. Main activities of the various sites include: Bologna: The headquarters are responsible for the institute management and act as interface with the INAF central headquarters in Roma. Much of the astronomical research is done in Bologna, with major areas in cosmology, extragalactic astrophysics, star formation and geodesy. -
On the Burning Mirrors of Archimedes, with Some Propositions Relating to the Concentration of Light Produced by Reectors of Different Forms
Transactions of the Royal Society of Edinburgh http://journals.cambridge.org/TRE Additional services for Transactions of the Royal Society of Edinburgh: Email alerts: Click here Subscriptions: Click here Commercial reprints: Click here Terms of use : Click here IV.—On the Burning Mirrors of Archimedes, with some Propositions relating to the concentration of Light produced by Reectors of different forms John Scott Transactions of the Royal Society of Edinburgh / Volume 25 / Issue 01 / January 1868, pp 123 - 149 DOI: 10.1017/S0080456800028143, Published online: 17 January 2013 Link to this article: http://journals.cambridge.org/abstract_S0080456800028143 How to cite this article: John Scott (1868). IV.—On the Burning Mirrors of Archimedes, with some Propositions relating to the concentration of Light produced by Reectors of different forms. Transactions of the Royal Society of Edinburgh, 25, pp 123-149 doi:10.1017/S0080456800028143 Request Permissions : Click here Downloaded from http://journals.cambridge.org/TRE, IP address: 129.93.16.3 on 13 Apr 2015 ( 123 ) IV.—On the Burning Mirrors of Archimedes, with some Propositions relating to the concentration of Light produced by Reflectors of different forms. By JOHN SCOTT, Esq., Tain. (Plate III.) (Bead 6th January 1868). As the reputed fact of ARCHIMEDES having burned the Roman ships engaged in the siege of Syracuse, by concentrating on them the solar rays, has not only been doubted but disbelieved by some of the most eminent scientific men, I shall briefly give the evidence on both sides. The burning of the ships of MARCELLUS is mentioned by most of the ancient writers who refer to the machines which ARCHIMEDES employed in the defence of his native city, and their statements have been repeated by succeeding authors, without any doubts having been expressed until comparatively recent times. -
Caliper Application Summary Report 20: LED PAR38 Lamps
Application Summary Report 20: LED PAR38 Lamps November 2012 Addendum September 2013 Prepared for: Solid-State Lighting Program Building Technologies Office Office of Energy Efficiency and Renewable Energy U.S. Department of Energy Prepared by: Pacific Northwest National Laboratory 1 Preface The U.S. Department of Energy (DOE) CALiPER program has been purchasing and testing general illumination solid-state lighting (SSL) products since 2006. CALiPER relies on standardized photometric testing (following the 1 Illuminating Engineering Society of North America [IES] approved method LM-79-08 ) conducted by accredited, 2 independent laboratories. Results from CALiPER testing are available to the public via detailed reports for each product or through summary reports, which assemble data from several product tests and provide comparative 3 analyses. It is not possible for CALiPER to test every SSL product on the market, especially given the rapidly growing variety of products and changing performance characteristics. Starting in 2012, each CALiPER summary report focuses on a single product type or application. Products are selected with the intent of capturing the current state of the market—a cross section ranging from expected low to high performing products with the bulk characterizing the average of the range. The selection does not represent a statistical sample of all available 4 products. To provide further context, CALiPER test results may be compared to data from LED Lighting Facts, 5 ™ ENERGY STAR® performance criteria, technical requirements for the DesignLights Consortium (DLC) Qualified 6 Products List (QPL), or other established benchmarks. CALiPER also tries to purchase conventional (i.e., non- SSL) products for comparison, but because the primary focus is SSL, the program can only test a limited number. -
The Meerkat Radio Telescope Rhodes University SKA South Africa E-Mail: a B Pos(Meerkat2016)001 Justin L
The MeerKAT Radio Telescope PoS(MeerKAT2016)001 Justin L. Jonas∗ab and the MeerKAT Teamb aRhodes University bSKA South Africa E-mail: [email protected] This paper is a high-level description of the development, implementation and initial testing of the MeerKAT radio telescope and its subsystems. The rationale for the design and technology choices is presented in the context of the requirements of the MeerKAT Large-scale Survey Projects. A technical overview is provided for each of the major telescope elements, and key specifications for these components and the overall system are introduced. The results of selected receptor qual- ification tests are presented to illustrate that the MeerKAT receptor exceeds the original design goals by a significant margin. MeerKAT Science: On the Pathway to the SKA, 25-27 May, 2016, Stellenbosch, South Africa ∗Speaker. c Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). http://pos.sissa.it/ MeerKAT Justin L. Jonas 1. Introduction The MeerKAT radio telescope is a precursor for the Square Kilometre Array (SKA) mid- frequency telescope, located in the arid Karoo region of the Northern Cape Province in South Africa. It will be the most sensitive decimetre-wavelength radio interferometer array in the world before the advent of SKA1-mid. The telescope and its associated infrastructure is funded by the government of South Africa through the National Research Foundation (NRF), an agency of the Department of Science and Technology (DST). Construction and commissioning of the telescope has been the responsibility of the SKA South Africa Project Office, which is a business unit of the PoS(MeerKAT2016)001 NRF. -
NATIONAL ACADEMIES of SCIENCES and ENGINEERING NATIONAL RESEARCH COUNCIL of the UNITED STATES of AMERICA
NATIONAL ACADEMIES OF SCIENCES AND ENGINEERING NATIONAL RESEARCH COUNCIL of the UNITED STATES OF AMERICA UNITED STATES NATIONAL COMMITTEE International Union of Radio Science National Radio Science Meeting 4-8 January 2000 Sponsored by USNC/URSI University of Colorado Boulder, Colorado U.S.A. United States National Committee INTERNATIONAL UNION OF RADIO SCIENCE PROGRAM AND ABSTRACTS National Radio Science Meeting 4-8 January 2000 Sponsored by USNC/URSI NOTE: Programs and Abstracts of the USNC/URSI Meetings are available from: USNC/URSI National Academy of Sciences 2101 Constitution Avenue, N.W. Washington, DC 20418 at $5 for 1983-1999 meetings. The full papers are not published in any collected format; requests for them should be addressed to the authors who may have them published on their own initiative. Please note that these meetings are national. They are not organized by the International Union, nor are the programs available from the International Secretariat. ii MEMBERSHIP United States National Committee INTERNATIONAL UNION OF RADIO SCIENCE Chair: Gary Brown* Secretary & Chair-Elect: Umran S. !nan* Immediate Past Chair: Susan K. Avery* Members Representing Societies, Groups, and Institutes: American Astronomical Society Thomas G. Phillips American Geophysical Union Donald T. Farley American Meteorological Society vacant IEEE Antennas and Propagation Society Linda P.B. Katehi IEEE Geosciences and Remote Sensing Society Roger Lang IEEE Microwave Theory and Techniques Society Arthur A. Oliner Members-at-Large: Amalia Barrios J. Richard Fisher Melinda Picket-May Ronald Pogorzelski W. Ross Stone Richard Ziolkowski Chairs of the USNC/URSI Commissions: Commission A Moto Kanda Commission B Piergiorgio L. E. Uslenghi Commission C Alfred 0. -
Wikipedia, the Free Encyclopedia
SKA newsletter Volume 21 - April 2011 The Square Kilometre Array Exploring the Universe with the world’s largest radio telescope www.skatelescope.org Please click the relevant section title to skip to that section 03 Project news 04 From the SPDO 05 SKA science 08 Engineering update 10 Site characterisation 12 Outreach update 14 Industry participation 17 News from around the world 18 Africa 20 Australia and New Zealand 23 Canada 25 China 28 Europe 31 India 33 US 35 Future meetings and events Project news Project news 04 From the SPDO Crucial steps for the SKA project were At its first meeting on 2 April, the Founding taken in the last week of March 2011. A Board decided that the location of the SKA Founding Board was created with the Project Office (SPO) will be at the Jodrell aim of establishing a legal entity for the Bank Observatory near Manchester in the project by the time of the SKA Forum in UK. This decision followed a competitive Canada in early July, as well as agreeing bidding process in which a number of the resourcing of the Project Execution excellent proposals were evaluated in an Plan for the Pre-construction Phase international review process. The SPO, which from 2012 to 2015. The Founding Board is hoped to grow to 60 people over the next replaces the Agencies SKA Group with four years, will supersede the SPDO currently immediate effect. Prof John Womersley based at the University of Manchester. The from the UK’s Science and Technology physical move to a new building at Jodrell Facilities Council (STFC) was elected Bank Observatory is scheduled for mid-2012.