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Getting Started in Radio Astronomy Steven Arnold Getting Started in Radio Astronomy Beginner Projects for the Amateur The Patrick Moore The Patrick Moore Practical Astronomy Series For further volumes: http://www.springer.com/series/3192 Getting Started in Radio Astronomy Beginner Projects for the Amateur Steven Arnold Steven Arnold Mans fi eld , UK ISSN 1431-9756 ISBN 978-1-4614-8156-0 ISBN 978-1-4614-8157-7 (eBook) DOI 10.1007/978-1-4614-8157-7 Springer New York Heidelberg Dordrecht London Library of Congress Control Number: 2013946929 © Springer Science+Business Media New York 2014 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, speci fi cally the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on micro fi lms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. Exempted from this legal reservation are brief excerpts in connection with reviews or scholarly analysis or material supplied speci fi cally for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Duplication of this publication or parts thereof is permitted only under the provisions of the Copyright Law of the Publisher’s location, in its current version, and permission for use must always be obtained from Springer. Permissions for use may be obtained through RightsLink at the Copyright Clearance Center. Violations are liable to prosecution under the respective Copyright Law. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a speci fi c statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. While the advice and information in this book are believed to be true and accurate at the date of publication, neither the authors nor the editors nor the publisher can accept any legal responsibility for any errors or omissions that may be made. The publisher makes no warranty, express or implied, with respect to the material contained herein. Cover illustration: Cover photo of the CSIRO Parkes Radio Telescope taken by Amanda Slater and used via creative commons license. Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) Dedication For Marjorie, I can’t imagine life without you or Sweep. With special thanks to; Shlomo, Lorraine and Josh, for their patience and proof reading skills and to Linda T for your encouragement. Also to the memory of three truly inspirational people that sadly died last year (2012). Sir Bernard Lovell; Radio astronomer at Jodrell Bank. Neil Armstrong; First man on the Moon. Sir Patrick Moore; Astronomer and true gentleman. About the Author Steven Arnold is a certi fi ed mechanical engineer and long-time amateur radio astronomer. He is a member of the Society for Popular Astronomy and has recently contributed radio astronomy articles about the NASA Radio Jove receiver kit and also wrote about the Stratospheric Observatory for Infrared Astronomy (SOFIA). He wrote and recorded a podcast about the NASA Radio Jove project, which can be heard on www.365daysofastronomy.org . Steve is a member of a number of astro- nomical groups and organizations. He has his own small permanent observatory and specializes in solar system deep-sky imaging, spectroscopy, and radio astronomy. vii Contents 1 The History of Radio Astronomy ............................................................ 1 1.1 The Early Years ................................................................................ 1 1.2 Wartime Developments .................................................................... 7 1.3 Increasing Resolution ....................................................................... 11 1.4 Planetary Signals .............................................................................. 16 1.5 Sputnik ............................................................................................. 17 1.6 The Search for Intelligent Life ......................................................... 19 1.7 The Apollo Mission ......................................................................... 20 1.8 Interferometry and Quasars .............................................................. 21 1.9 Observation of Mercury ................................................................... 23 1.10 The ‘Big Bang’ Theory and CMB ................................................... 24 1.11 Neutron Stars and Pulsars ................................................................ 26 1.12 Arecibo Transmission and ‘Wow!’ Signal ....................................... 28 2 The Basic Physics of Electricity and Magnetism ................................... 33 2.1 Building Blocks ............................................................................... 33 2.2 Magnetism and Wave Properties ...................................................... 35 2.3 The Electromagnetic Spectrum ........................................................ 39 2.4 Radio Frequencies and Characteristics ............................................ 42 3 Atmosphere, Magnetic Fields and Magnetospheres .............................. 49 3.1 The Goldilocks Zone ........................................................................ 49 3.2 The Ionosphere ................................................................................. 51 3.3 Scintillation ...................................................................................... 54 3.4 Planetary Magnetic Fields and Magnetospheres .............................. 55 ix x Contents 4 Electrical Components .............................................................................. 61 4.1 A Brief Review of Electrical Safety................................................... 61 4.2 Soldering ............................................................................................ 62 4.3 Multimeters ........................................................................................ 66 4.4 Electrical Component Identification .................................................. 68 4.5 Headphones ........................................................................................ 77 5 The Stanford Solar Center, SuperSID Monitor ..................................... 81 5.1 Space Weather and Its Dangers to Earth ............................................ 84 5.2 A Basic Description of How the SuperSID Monitor Works .............. 85 5.3 How to Make an Antenna .................................................................. 88 5.4 Placing the SuperSID Antenna .......................................................... 94 5.5 Computer Sound Cards and Software ................................................ 95 5.6 Connecting Everything Together ....................................................... 98 5.7 Interpreting the Data .......................................................................... 102 5.8 X-ray Classification ........................................................................... 105 5.9 Resources for More Information ........................................................ 106 6 The NASA INSPIRE Project ................................................................... 109 6.1 What Is the INSPIRE Project? ........................................................... 109 6.2 A Guide to Building an INSPIRE Receiver ....................................... 111 6.3 Manmade VLF Radio Emissions and How to Choose an Observing Site .............................................. 119 6.4 Natural Radio Emissions .................................................................... 122 6.5 Radio Emissions from Beyond the Grave? ........................................ 125 6.6 Recording VLF .................................................................................. 126 6.7 Analyzing Software and Where to Get It ........................................... 129 6.8 References for More Information ...................................................... 133 7 The NASA Radio Jove Project ................................................................. 135 7.1 About Radio Jove ............................................................................... 135 7.2 A Guide to Building the Radio Jove Receiver ................................... 137 7.3 Building the Radio Jove Antennas ..................................................... 144 7.4 Antenna Configurations ..................................................................... 150 7.5 Software ............................................................................................. 154 7.6 Calibration .......................................................................................... 158 7.7 Radio Emissions from the Sun ........................................................... 160 7.8 Radio Emissions from the Planet Jupiter ........................................... 164 7.9 References for More Information ...................................................... 166 8 Radio Detection of Meteors ...................................................................... 169 8.1 Meteoroid, Meteor, Meteorite and Micrometeorites .......................... 169 8.2 What Is Radio Detection of Meteors? ................................................ 171 8.3 When to Listen ..................................................................................
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