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The Comet's Tale THE COMET’S TALE Newsletter of the Comet Section of the British Astronomical Association Volume 12, No 1 (Issue 23), 2005 April The George Alcock Memorial Plaque and this has been plaque. It was transposed from a used to copy of one of George's drawings. commemorate his A nova is engraved at the lower name in two end of the plaque. Two pointers ways. Annual have been cut into the slate to “George Alcock identify the nova, and have been memorial highlighted with red paint. The lectures” are stars in the background fields given, where the have been engraved and laid in speaker talks with 'leaf' of the rare metal about some aspect palladium, which shines like of George’s life. silver but does not tarnish. The first lecture was given by The plaque was unveiled on 2005 Brian Marsden April 19 in a moving ceremony, and related to his in front of a congregation of cometary around 100. The proceedings observations. commenced with an address from Last year Bill the Dean of the Cathedral, the Livingston gave a very Reverend Michael Bunker, lecture on followed by the BAA President, meteorological Tom Boles. He handed over to phenomena seen Professor Sir Martin Rees, the from Kitt Peak in Astronomer Royal to carry out the a joint meeting unveiling. between the BAA and the Royal Photo J Boyce Ellingham Meteorological Society. The name of George Alcock (1912 – 2000) is legendary In parallel with these inaugural amongst amateur astronomers, but lectures, David Tucker, the BAA his interests were wide ranging, treasurer, was commissioning a covering the fields of memorial plaque, which was to be archaeology, church architecture, installed in Peterborough Sir Martin unveils the plaque geology, meteorology and natural cathedral, a site that George had history in addition to astronomy. visited many times. Getting Contents A full biography of this wonderful permission to install the plaque Comet Section contacts 2 Peterborough school teacher was was a complex process, and the Section news 2 written by Kay Williams with the cathedral authorities had to be Tales from the past 4 title “Under an English Heaven. satisfied that it would be suitable George Alcock memorial 5 The Life of George Alcock” for the ancient foundation. Professional tales 6 published by Genesis Publications Prospects for 2005 8 Ltd. 1996. ISBN 0-904351 556 The plaque was designed and Review of observations 12 carved by Ronald Parsons. A He left a significant legacy to the comet, with background star field, British Astronomical Association is engraved at the top of the BAA COMET SECTION NEWSLETTER 2 THE COMET'S TALE Comet Section contacts Director: Jonathan Shanklin, 11 City Road, CAMBRIDGE. CB1 1DP, England. Phone: (+44) (0)1223 571250 (H) or (+44) (0)1223 221400 (W) Fax: (+44) (0)1223 221279 (W) or (+44) (0) 1223 571250 (H) E-Mail: [email protected] or [email protected] WWW page : http://www.ast.cam.ac.uk/~jds/ Assistant Director (Observations): Guy Hurst, 16 Westminster Close, Kempshott Rise, BASINGSTOKE, Hampshire. (and also Editor of RG22 4PP, England. The Astronomer magazine) Phone & Fax: (+44) (0)1256 471074 E-Mail: [email protected] or [email protected] Assistant Director (CCD): Nick James, 11 Tavistock Road, CHELMSFORD, Essex. CM1 5JL, England. Phone: (+44) (0)1245 354366 E-mail: [email protected] Photographic Advisor: Michael Hendrie, Overbury, 33 Lexden Road, West Bergholt, COLCHESTER, Essex, CO6 3BX, England Phone: (+44) (0)1206 240021 The Section newsletter is now free to all BAA Members who make contributions to the work of the Section. The cost for other postal subscribers is £5 for two years, extended to three years for those who contribute to the work of the Section in any way, for example by submitting observations or articles. Renewals should be sent to the Director and cheques made payable to the BAA. Those due to renew should receive a reminder with this mailing. You can also download the newsletter (in colour) from the Section web page. Section News from the Director Dear Section member, friends, former pupils and last roll of Kodachrome film was astronomical colleagues. One returned with a note saying please The unveiling of the plaque to day, perhaps, someone will follow could I send the next one to George Alcock in Peterborough in his footsteps and inspire Switzerland for developing. Cathedral was a memorable event. another generation in natural Clearly digital cameras are The last plaque in the cathedral history, meteorology, architecture driving out the traditional dedicated to a person was and astronomy. photographic techniques, and I unveiled over a decade ago, and must admit that my digital SLR Sir Martin had only unveiled a CCDs can’t yet rival the vis ual easily outdoes the astronomical couple of other plaques to acuity of George Alcock, but they photographs taken with my old astronomers or buildings. are rapidly become the dominant camera and slide film, and I can Amongst the on lookers were force in amateur astronomy. I see the results in seconds. I hope some of George’s family, his was somewhat surprised when my the meeting that many of you are at today will help improve and standardise your observations, and the next issue of the newsletter will contain detailed reports for those that weren’t able to make it. Thanks are due to Nick James for organising the speakers, and generating what I hope will be a lively debate on techniques. I’ve received the sad news of the death of Michiel Bester, at the age of 87. Mike discovered six comets from South Africa (1946 U1, 1947 F1, 1947 K1, 1947 S1, 1948 W1 and 1959 O1). 1947 S1 was well observed in the spring of 1948, but I don’t have records for any of the others in the Section archives. There is more information about South African Tom Boles and Professor Sir Martin Rees comet discoveries on the web at BAA COMET SECTION NEWSLETTER 2005 APRIL 3 http://www.saao.ac.za/assa/2003 A’Hearn who is a PI for the me know- you can of course get MNSSA..62..170C.pdf mission, and other well known them yourself from the CBAT planetary scientists such as Ron web page. I am pleased to announce the Greeley, Caroline Porco, Steven award of the final Keedy Award Squyres and John Zarnecki. Since the last newsletter to Jeremy Shears. Jeremy has observations or contributions have spent much time abroad working An interesting discovery is that been received from the following with Shell, and has only recently some of the SOHO “sunskirting” BAA members: Peter Birtwhistle, returned to the UK. He has taken comets of the Marsden and allied Roger Dymock, Massimo up CCD imaging of comets, and Kracht groups are periodic, and Giuntoli, Werner Hasubick, Guy has achieved excellent results in a are also linked to 96P/Machholz Hurst, Nick James, Geoffrey very short space of time. Thanks and the delta Aquarid, Quadrantid Johnstone, Martin Mobberley, are due to David Keedy for his and daytime Arietid meteors. Gabriel Oksa, Jonathan Shanklin, long running support of the Zdenek Sekanina and Paul Jeremy Shears, Cliff Turk, Alex Comet Section, in particular Chodas demonstrate that a whole Vincent, and also from: Jose through the Keedy Award. spectrum of orbits of fragments Aguiar, Alexandre Amorim, Alexander Baransky, Nicolas Biver, Jose Carvajal, Stephen Getliffe, JJ Gonzalez, Michael Jager, Andreas Kammerer, Heinz Kerner, Carlos Labordena, Martin Lehky, Rolando Ligustri, Michael Mattiazzo, Maciej Reszelski, Juan San Juan, Pepe Manteca, Jose Martinez, Stuart Rae, Walter Robledo, Tony Scarmato, and Seiichi Yoshida (apologies for any errors or omissions). Without these contributions it would be impossible to produce the comprehensive light curves that appear in each issue of The Comet’s Tale. Observations from groups that currently do not send observations to the BAA would be much appreciated as they make a valuable addition to the analyses. Comets under observation were: 9P/Tempel, 29P/Schwassmann- Wachmann, 32P/Comas Sola, 49P/Arend- can be generated from the Rigaux, 56P/Slaughter-Burnham, The big event coming up is the breakup of a parent comet over 62P/Tsuchinshan, 69P/Taylor, encounter of Deep Impact with 1000 years ago. Hopefully SOHO 78P/Gehrels, 121P/Shoemaker-Holt, 9P/Tempel. Hopefully NASA will continue long enough to 141P/Machholz, 162P/Siding Spring, will have been able to solve the detect more fragments before its 164P/Christensen, 2001 Q4 (NEAT), 2002 focus problem with their camera successors are in orbit and help T7 (LINEAR), 2003 K4 (LINEAR), 2003 (now where have I heard that improve our understanding of the T4 (LINEAR), 2003 WT42 (LINEAR), before?) and we will get even possible dangers associated with 2004 B1 (LINEAR), 2004 Q1 (Tucker), more stunning images than those this stream of objects, which 2004 Q2 (Machholz), 2004 T1 recently returned from the surface clearly do hit the earth. Brian (P/LINEAR-NEAT), 2004 U1 (LINEAR), of Titan. Amateur observations Marsden has predicted a return of 2004 V13 (SWAN) and 2005 A1 may play a part in determining several fragments in late April (LINEAR). exactly what happens as it is and mid May, and if these are amateur observations that will be seen, I suggest that the parent It seems that most people want to used to compare the light curve at comet is named “Marsden”. keep receiving the newsletter in this return with those of previous printed, low resolution, black & returns. We will be getting Geoffrey Johnstone has a set of white form, rather than download detailed reports from the the IHW Halley archive volumes, the colour pdf for themselves to professionals in September, when which he no longer wants.
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