CRAF Handbook for Radio Astronomy
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Pos(Westerbork)002 Historical Introduction Historical S 4.0 International License (CC BY-NC-ND 4.0)
Historical Introduction PoS(Westerbork)002 Richard Strom ASTRON Oude Hoogeveensedijk 4, 7991 PD Dwingeloo, The Netherlands E-mail: [email protected] 50 Years Westerbork Radio Observatory, A Continuing Journey to Discoveries and Innovations Richard Strom, Arnold van Ardenne, Steve Torchinsky (eds) Published with permission of the Netherlands Institute for Radio Astronomy (ASTRON) under the terms of the Creative CommonsAttribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). Chapter 1 Historical introduction Richard Strom* rom the English longbows at the battle of Crécy (1346) to Winston Chur- chill’s world war I mobilized cannon (its true identity hidden behind the Fpseudonym “[water] tank”), warfare has always pushed technological innovation to new fronts. The second world war (WWII) was no exception. It gave us technology ranging from the dynamo-powered flashlight (a Philips invention) to jet engines, and space-capable rockets (Germany’s V2), not to mention (in a completely different realm) the mass production of Penicillin. In fact, it could be argued that WWII inventions marked the inception of the modern technological era1. In the field of electronics, the war led to innovations such as radio navigation, aircraft landing systems, and radar. It was these developments which were to * ASTRON, Univer- sity of Amsterdam, have a revolutionary impact on astronomy, initially in Britain, Australia and the The Netherlands United States. But the story begins in the US, with the electronics of the 1920s and ‘30s. Figure 1. Karl G. Jansky (c. 1933) Around 1930, there was increasing interest in the use of radio frequencies for communication. One of the main players, the Bell Telephone Laboratories in New Jersey, asked their research engineer, Karl Jansky (Figure 1), to investigate the inter- ference environment in the “short-wave” band around 20 MHz. -
1. INTRODUCTION 2. EASY INSTALLATION GUIDE 8. Explain How to Download S/W by USB and How to Upload and Download 9. HOW to DOWNLO
1. INTRODUCTION Overview…………………………………………………………………………..………………...……... 2 Main Features……………………………………………………………………………... ...………... ....4 2. EASY INSTALLATION GUIDE...…………...…………...…………...…………...……….. .. 3 3. SAFETY Instructions.………………………………………………………………………… …6 4. CHECK POINTS BEFORE USE……………………………………………………………… 7 Accessories Satellite Dish 5. CONTROLS/FUNCTIONS……………………………………………………………………….8 Front/Rear panel Remote controller Front Display 6. EQUIPMENT CONNECTION……………………………………………………………....… 11 CONNECTION WITH ANTENNA / TV SET / A/V SYSTEM 7. OPERATION…………………………………………………………………….………………….. 12 Getting Started System Settings Edit Channels EPG CAM(COMMON INTERFACE MODULE) Only CAS(CONDITIONAL ACCESS SYSTEM) USB Menu PVR Menu 8. Explain how to download S/W by USB and how to upload and download channels by USB……………………….……………………………………….…………………31 9. HOW TO DOWNLOAD SOFTWARE FROM PC TO RECEIVER…………….…32 10. Trouble Shooting……………………….……………………………………….………………34 11. Specifications…………………………………………………………………….……………….35 12. Glossary of Terms……………………………………………………………….……………...37 1 INTRODUCTION OVERVIEW This combo receiver is designed for using both free-to-air and encrypted channel reception. Enjoy the rich choice of more than 20,000 different channels, broadcasting a large range of culture, sports, cinema, news, events, etc. This receiver is a technical masterpiece, assembled with the highest qualified electronic parts. MAIN FEATURES • High Definition Tuners : DVB-S/DVB-S2 Satellite & DVB-T Terrestrial Compliant • DVB-S/DVB-S2 Satellite Compliant(MPEG-II/MPEG-IV/H.264) -
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. -
Radio Astronomy
Theme 8: Beyond the Visible I: radio astronomy Until the turn of the 17th century, astronomical observations relied on the naked eye. For 250 years after this, although astronomical instrumentation made great strides, the radiation being detected was still essentially confined to visible light (Herschel discovered infrared radiation in 1800, and the advent of photography opened up the near ultraviolet, but these had little practical significance). This changed dramatically in the mid-20th century with the advent of radio astronomy. 8.1 Early work: Jansky and Reber The atmosphere is transparent to visible light, but opaque to many other wavelengths. The only other clear “window” of transparency lies in the radio region, between 1 mm and 30 m wavelength. One might expect that the astronomical community would deliberately plan to explore this region, but in fact radio astronomy was born almost accidentally, with little if any involvement of professional astronomers. Karl Jansky (1905−50) was a radio engineer at Bell Telephone. In 1932, while studying the cause of interference on the transatlantic radio-telephone link, he discovered that part of the interference had a periodicity of one sidereal day (23h 56m), and must therefore be coming from an extraterrestrial source. By considering the time at which the interference occurred, Jansky identified the source as the Milky Way. This interesting finding was completely ignored by professional astronomers, and was followed up only by the radio engineer and amateur astronomer Grote Reber (1911−2002). Reber built a modern-looking paraboloid antenna and constructed maps of the radio sky, which also failed to attract significant professional attention. -
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 -
Messenger-No117.Pdf
ESO WELCOMES FINLANDINLAND AS ELEVENTH MEMBER STAATE CATHERINE CESARSKY, ESO DIRECTOR GENERAL n early July, Finland joined ESO as Education and Science, and exchanged which started in June 2002, and were con- the eleventh member state, following preliminary information. I was then invit- ducted satisfactorily through 2003, mak- II the completion of the formal acces- ed to Helsinki and, with Massimo ing possible a visit to Garching on 9 sion procedure. Before this event, howev- Tarenghi, we presented ESO and its scien- February 2004 by the Finnish Minister of er, Finland and ESO had been in contact tific and technological programmes and Education and Science, Ms. Tuula for a long time. Under an agreement with had a meeting with Finnish authorities, Haatainen, to sign the membership agree- Sweden, Finnish astronomers had for setting up the process towards formal ment together with myself. quite a while enjoyed access to the SEST membership. In March 2000, an interna- Before that, in early November 2003, at La Silla. Finland had also been a very tional evaluation panel, established by the ESO participated in the Helsinki Space active participant in ESO’s educational Academy of Finland, recommended Exhibition at the Kaapelitehdas Cultural activities since they began in 1993. It Finland to join ESO “anticipating further Centre with approx. 24,000 visitors. became clear, that science and technology, increase in the world-standing of ESO warmly welcomes the new mem- as well as education, were priority areas Astronomy in Finland”. In February 2002, ber country and its scientific community for the Finnish government. we were invited to hold an information that is renowned for its expertise in many Meanwhile, the optical astronomers in seminar on ESO in Helsinki as a prelude frontline areas. -
Kinematic and Emission Analysis of the Relativistic Jet in the Blazar B1551+130 Using VLBI Data
Kinematic and Emission Analysis of the Relativistic Jet in the Blazar B1551+130 using VLBI Data Shaun Julian Nicol MSci Project Imperial College London Host Institute: Supervisor: Universitat de Val`encia Prof. Eduardo Ros Ibarra June 2012 Abstract Very Long Baseline Interferometry (VLBI) allows the most energetic structures in our universe to be observed with sub-milliarcsecond resolution (parsecs at cosmological distances). These methods are particularly effective in observing the relativistic jets extending from the black hole region of active galactic nu- clei (AGN). Six epochs of VLBI data from the MOJAVE 2 cm survey taken between June 2009 and April 2012 are used to carry out the kinematic analysis of the relativistic jet in the flat spectrum radio quasar B1551+130 with red- shift z = 1:308. The apparent velocities of areas of enhanced radio emission, or `knots', in the jet, calculated through the model fitting technique, are pre- sented along with images of the source obtained through the hybrid mapping process. Superluminal velocities for the `knots' are observed with the highest apparent velocity being 10.21.8c. From this maximum velocity, the viewing angle of 5.6◦ 1◦ is derived, agreeing with the classification of the source as a FSRQ. An estimate of the luminosity Doppler boosting factor gives a value of order 102. Two jet features are observed with negative superluminal velocities, the most significant being the region closest to the base or `core' of the jet ob- served with a velocity of {10.62.7c. The flux of this region undergoes a large increase during the most recent observations, between mid 2011 and mid 2012. -
Adventures in Radio Astronomy Instrumentation and Signal Processing
Adventures in Radio Astronomy Instrumentation and Signal Processing by Peter Leonard McMahon Submitted to the Department of Electrical Engineering in partial fulfillment of the requirements for the degree of Master of Science in Electrical Engineering at the University of Cape Town July 2008 Supervisor: Professor Michael Inggs Co-supervisors: Dr Dan Werthimer, CASPER1, University of California, Berkeley Dr Alan Langman, Karoo Array Telescope arXiv:1109.0416v1 [astro-ph.IM] 2 Sep 2011 1Center for Astronomy Signal Processing and Electronics Research Abstract This thesis describes the design and implementation of several instruments for digi- tizing and processing analogue astronomical signals collected using radio telescopes. Modern radio telescopes have significant digital signal processing demands that are typically best met using custom processing engines implemented in Field Pro- grammable Gate Arrays. These demands essentially stem from the ever-larger ana- logue bandwidths that astronomers wish to observe, resulting in large data volumes that need to be processed in real time. We focused on the development of spectrometers for enabling improved pulsar2 sci- ence on the Allen Telescope Array, the Hartebeesthoek Radio Observatory telescope, the Nan¸cay Radio Telescope, and the Parkes Radio Telescope. We also present work that we conducted on the development of real-time pulsar timing instrumentation. All the work described in this thesis was carried out using generic astronomy pro- cessing tools and hardware developed by the Center for Astronomy Signal Processing and Electronics Research (CASPER) at the University of California, Berkeley. We successfully deployed to several telescopes instruments that were built solely with CASPER technology, which has helped to validate the approach to developing radio astronomy instruments that CASPER advocates. -
Downloading New Content Automatically As It Becomes Available
The Jodcast N. J. Rattenbury Jodrell Bank Centre for Astrophysics, The University of Manchester Summary. The Jodcast (www.jodcast.net) is a twice-monthly astro- nomy podcast from The University of Manchester©s Jodrell Bank Observatory. In this paper I give the motivation and history of The Jodcast, as well as a description of The Jodcast©s content, opera- tions, personnel, performance and aspirations. 1 Introduction Every day during the school vacations, visitors to Jodrell Bank Ob- servatory gather around a volunteer JBO astronomer to listen to a short history of the Observatory, followed by an opportunity to ask their questions on space and astronomy. This is the ªAsk-An-As- tronomerº session, and usually draws crowds of 20-30 people. Following one such session, a debate ensued in the corridor of the JBO control building on whether such a modest audience size justified the time spent by a research-grade astronomer to perform this public outreach service. The question became one of audience size: by what means can such science outreach be done effectively and efficiently to as large an audience as possible? Creating a podcast appeared the logical answer to this question, and had been informally discussed previously amongst several peo- ple at JBO. A podcast is a piece of audio/video or other content ºbroadcastº over the internet. Users from anywhere in the world can 2 N. J. Rattenbury subscribe to the content, downloading new content automatically as it becomes available. Podcasting is rapidly becoming a routine form of media delivery for all broadcasters; mainstream or otherwise. -
High Resolution Radio Astronomy Using Very Long Baseline Interferometry
IOP PUBLISHING REPORTS ON PROGRESS IN PHYSICS Rep. Prog. Phys. 71 (2008) 066901 (32pp) doi:10.1088/0034-4885/71/6/066901 High resolution radio astronomy using very long baseline interferometry Enno Middelberg1 and Uwe Bach2 1 Astronomisches Institut, Universitat¨ Bochum, 44801 Bochum, Germany 2 Max-Planck-Institut fur¨ Radioastronomie, Auf dem Hugel¨ 69, 53121 Bonn, Germany E-mail: [email protected] and [email protected] Received 3 December 2007, in final form 11 March 2008 Published 2 May 2008 Online at stacks.iop.org/RoPP/71/066901 Abstract Very long baseline interferometry, or VLBI, is the observing technique yielding the highest-resolution images today. Whilst a traditionally large fraction of VLBI observations is concentrating on active galactic nuclei, the number of observations concerned with other astronomical objects such as stars and masers, and with astrometric applications, is significant. In the last decade, much progress has been made in all of these fields. We give a brief introduction to the technique of radio interferometry, focusing on the particularities of VLBI observations, and review recent results which would not have been possible without VLBI observations. This article was invited by Professor J Silk. Contents 1. Introduction 1 2.9. The future of VLBI: eVLBI, VLBI in space and 2. The theory of interferometry and aperture the SKA 10 synthesis 2 2.10. VLBI arrays around the world and their 2.1. Fundamentals 2 capabilities 10 2.2. Sources of error in VLBI observations 7 3. Astrophysical applications 11 2.3. The problem of phase calibration: 3.1. Active galactic nuclei and their jets 12 self-calibration 7 2.4. -
What Is Dark Matter
What is Dark Ma,er? History of what the universe is made of, through 2003 Zackary Scholl October 8th, 2009 Early astronomy methods • Measuring distances to galaxies – “Standard candle” Type Ia Supernova used to measure distance to galaxies (1-100 Mps) • Measuring velociQes of galaxies – Speed is proporQonal to amount of Doppler shiR in emission and absorpQon lines Early astronomy methods • EsQmaQng masses of galaxies – From mass to luminosity raQo (M/L) • Based on the sun (Sun’s M/L = 1) • Our galaxy has M/L is 6 – From rotaQonal velocity of gas clouds and stars • Kepler’s laws of moQon say that faster stellar moQons are caused by larger mass concentraQon First menQon of “dark ma,er” • In 1933 Fritz Zwicky analyzed velociQes of galaxies in Coma cluster • Calculated mass was 50 Qmes larger than mass esQmated from luminosity. “If this is confirmed we would arrive at the astonishing conclusion that dark maer is present with much greater density than luminous ma,er.” – Zwicky, 1933 More missing mass… • In 1936 Sinclair Smith concluded Virgo galaxy has 10 Qmes the mass esQmated from luminosity. • In 1940 Jan Oort concluded NGC 3115 has 25 Qmes mass esQmated from luminosity. “[T]he distribuQon of mass in this system appears to bear almost no relaQon to that of light.“ – Oort 1940 Be,er astronomy methods • In 1950’s astronomers started using radio telescopes • In 1960’s astronomers started using X-ray telescopes • Astronomers began invesQgaQng dynamics of galaxies • Evidence accumulated for idea of missing mass Evidence of “missing ma,er” • In -
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Table of contents - 1 - - 2 - Table of Contents Foreword 5 1. The European Consortium for VLBI 7 2. Scientific highlights on EVN research 9 3. Network Operations 35 4. VLBI technical developments and EVN operations support at member institutes 47 5. Joint Institute for VLBI in Europe (JIVE) 83 6. EVN meetings 105 7. EVN publications in 2007-2008 109 - 3 - - 4 - Foreword by the Chairman of the Consortium The European VLBI Network (EVN) is the result of a collaboration among most major radio observatories in Europe, China, Puerto Rico and South Africa. The large radio telescopes hosted by these observatories are operated in a coordinated way to perform very high angular observations of cosmic radio sources. The data are then correlated by using the EVN correlator at the Joint Institute for VLBI in Europe (JIVE). The EVN, when operating as a single astronomical instrument, is the most sensitive VLBI array and constitutes one of the major scientific facilities in the world. The EVN also co-observes with the Very Long Baseline Array (VLBA) and other radio telescopes in the U.S., Australia, Japan, Russia, and with stations of the NASA Deep Space Network to form a truly global array. In the past, the EVN also operated jointly with the Japanese space antenna HALCA in the frame of the VLBI Space Observatory Programme (VSOP). The EVN plans now to co-observe with the Japanese space 10-m antenna ASTRO-G, to be launched by 2012, within the frame of the VSOP-2 project. With baselines in excess of 25.000 km, the space VLBI observations provide the highest angular resolution ever achieved in Astronomy.