Astronomers’ Observing Guides For other titles published in this series, go to www.springer.com/series/5338 wwwwwww Roger Dymock Asteroids and Dwarf Planets and How to Observe Them with 152 Illustrations Roger Dymock 67 Haslar Crescent Waterlooville Hampshire PO7 6DD United Kingdom [email protected] Series Editor Dr. Mike Inglis, BSc, MSc, Ph.D. Fellow of the Royal Astronomical Society Suffolk County Community College New York, USA [email protected] Please note that additional material for this book can be downloaded from http://extras.springer.com ISBN 978-1-4419-6438-0 e-ISBN 978-1-4419-6439-7 DOI 10.1007/978-1-4419-6439-7 Springer New York Dordrecht Heidelberg London Library of Congress Control Number: 2010938909 © Springer Science+Business Media, LLC 2010 All rights reserved. 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Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) Acknowledgements s t n w­e m o e n g k d c Ae While writing this book I requested the help of many amateur and professional l astronomers with images, diagrams, specific projects, and those sections with which I was not familiar. I have been truly amazed with their responses – my requests were answered speedily and additional images and information were fre- quently offered. My only hope is that this book does justice to their efforts. First of all I must thank my wife, Jean for her support. As long as I don’t wake her in the middle of the night or interfere with her tennis she is happy for me to indulge in matters astronomical. Actually she does have more than a passing inter- est in astronomy, having completed the same basic course as I did, run by Hampshire Astronomical Group’s Past President, Robin Gorman. Both having had a painful bunion removed I sometimes felt that their conversation was more ana- tomical than astronomical! When I first mentioned writing this book she had visions of Harry Potter like riches − well you never know, but I definitely (well, almost definitely) won’t be writing another! Many, many thanks to the following (apologies for not including titles as they were not always given in communications): David C. Agle (National Aeronautics and Space Administration Jet Propulsion Laboratory – NASA JPL), Paul G. Allen Charitable Foundation, Eamonn Ansbro, Molly Birtwhistle, Peter Birtwhistle, John Broughton – Scanalyzer and ScanTracker, Michael R. Buckley (NASA Johns Hopkins University Applied Physics Laboratory), Marc Buie (Lowell Observatory), L. Calçada (European Southern Observatory – ESO), California Institute of Technology – Caltech, Alan Chamberlain, Michael Clarke, Steven K. Croft, Martin Crow, Earth Impact Database, ELB software – Megastar, Andrew Elliott, Brian Fessler (Lunar and Planetary Institute – LPI), Eric Frappa (Euraster), Maurice Gavin, Eric Graff, Mary Ann Hager (LPI), Alan W. Harris (Space Science Institute), Tsutomu Hayamizu, Carl Hergenrother, David Higgins, Nadia Imbert-Vier (European Space Agency – ESA), Chris Hooker, Suzanne H. Jacoby (Large Synoptic Survey Telescope), Nick James, David Jewitt, Richard Judd (Hampshire Astro- nomical Group), Scott Cardel (Caltech, Palomar Observatory), Mikko Kaasalainen (Tampere University of Technology), Guido Kosters (ESA), David Kring (LPI), Stefan Kurti, Marco Langbroek, Rob Matson, Robert McMillan (Spacewatch FMO Project), Rob McNaught (Siding Spring Observatory), Richard Miles (Director, Asteroids and Remote Planets Section, British Astronomical Association), Martin Mobberley, NASA National Space Science Data Center – NSSDC, NASA Skymorph, Near Earth Asteroid Rendezvous mission – NEAR, Tomomi Niizeki (Japan Aerospace Exploration Agency – JAXA), Richard N. Nugent, Chris Peterson, Project Pluto – Find_Orb and Guide, Herbert Raab – Astrometrica, Monty Robson, Lou Scheffer, Jean Schwaenen (European Asteroidal Occultation Network – EAON), Brett Simison (Panoramic Survey Telescope & Rapid Response System – Pan- STARRS), John Saxton, Jean Schwaenen (EAON), Space Telescope Science Institute – STScI, Tim Spahr (Minor Planet Center – MPC), Alan Stern (Southwest Research v Institute), John Sussenbach, Roy Tucker, University of Arizona, Višnjan School of Astronomy, Brian Warner (Minor Planet Observer – MPO and Collaborative Asteroid Lightcurve Link – CALL), Gareth V. Williams (MPC), Rich Williams s t (Sierra Stars Observatory Network – SSON). n w­e My astronomical ‘career’ began with my local astronomical society – the m Hampshire Astronomical Group − and I subsequently joined the British o ne Astronomical Association, The Astronomer Group, and the Royal Astronomical g k Society. Many members of those organizations have given me advice along the way, d c Ae for which I am grateful. l All my (electronic) scribblings have been proofread by Hazel McGee, long time BAA member and editor of the Journal of the British Astronomical Association. We haven’t always seen eye-to-eye, but mostly we did, and thus the text is somewhat improved from the original. Thank you so much Hazel. Finally my thanks to my Springer contacts: Michael Inglis, Turpana Molina, Maury Solomon, and John Watson. Their requirement to submit a detailed struc- ture of the book helped me break down its writing into manageable sections and keep to the proposed schedule. Martin Mobberley likened writing a book to climb- ing a mountain and having those ‘camps’ along the way certainly eased the path to the summit. It seemed quite an omission to me that, to the best of my knowledge, no similar book existed, since many other aspects of amateur astronomy, e.g., comets, lunar, planetary, solar and variable stars were well catered for. Our knowledge of aster- oids has increased rapidly of late – even during the time it has taken to write this book. Perhaps having set the ball rolling others will be encouraged to follow in my footsteps. vi About the Author Roger Dymock lives in Hampshire, England. He is a Fellow of the Royal Astronomical Society and was the Director of the Asteroids and Remote Planets Section of the British Astronomical Association from 2005 to 2008. His published work includes Journal of the BAA: “The Observapod – a GRP observatory”; Minor Planet Bulletin, No. 32 2005: “Lightcurve of 423 Diotima”; Sky at Night magazine: “How to track an asteroid”; and Journal of the BAA: “A method for determining the V magnitude of asteroids from CCD images” (jointly with Dr Richard Miles). e h t r to u h o t bu AA vii wwwwwww Contents Acknowledgements ................................................................................................. v Part I Asteroids and Dwarf Planets Chapter 1 Introduction ....................................................................................... 003 Chapter 2 Small (and Not So Small) Solar System Bodies .............................. 009 Planets and Dwarf Planets ............................................................................... 009 Resolution 5 ................................................................................................... 010 Resolution 6 ................................................................................................... 010 Asteroids ............................................................................................................ 011 Designations Old and New ............................................................................... 013 Numbering and Naming .................................................................................. 014 Asteroid Orbits .................................................................................................. 014 Lost? Perhaps Not ............................................................................................. 017 Chapter 3 Groups and Families .......................................................................... 019 Asteroid Groups ................................................................................................ 019 Vulcanoids ......................................................................................................... 020 Near-Earth Asteroids/Objects (NEAs/Os) ...................................................... 020 The Main Belt .................................................................................................... 022 Trojans ............................................................................................................... 023 s t Locations and Numbers ............................................................................... 023 n e Martian Trojans ............................................................................................ 023 t n Jupiter (or Jovian) Trojans ........................................................................... 024 o Neptune Trojans ............................................................................................ 024 C Centaurs ............................................................................................................. 025 The Edgeworth–Kuiper Belt ............................................................................ 025 Plutinos and Plutoids ....................................................................................... 026 Classical Edgeworth–Kuiper Belt Objects ...................................................... 027 Scattered Disk Objects ...................................................................................... 028 Detached Objects .............................................................................................. 028 And Finally… .................................................................................................... 028 Moons ................................................................................................................ 029 Classical Orbits ............................................................................................. 029 Quasi-Satellites and Horseshoe Orbits ....................................................... 029 Dwarf Planets .................................................................................................... 030 Exosolar Asteroids ............................................................................................ 030 Summary ........................................................................................................... 030 ix