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Evolution of Halley-Type Comets and Meteoroid Streams

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Evolution of Halley-type Comets and Meteoroid Streams A thesis submitted for the degree of Doctor of Philosophy in Physics by Aswin Sekhar, B.Sc., M.Sc., M.Phil. Armagh Observatory United Kingdom & School of Mathematics and Physics The Queen's University of Belfast United Kingdom Apr 2014 Declaration This thesis was submitted for evaluation and accepted after examination in accordance with the requirements for the Degree of Doctor of Philosophy in Physics of the Queen's University of Belfast, United Kingdom. I certify that the contents of this thesis is solely my own work, other than where I have clearly indicated so, and has not been presented for the award of any other degree, title or fellowship elsewhere. External Examiner: Dr J´er´emieVaubaillon Institut de M´ecanique C´elesteet de Calcul des Eph´em´erides´ Paris Observatory, France Internal Examiner: Dr Apostolos Christou Armagh Observatory, United Kingdom Principal Supervisor: Dr David Asher Armagh Observatory, United Kingdom Ph.D Candidate: Aswin Sekhar Student Number: 29056314 Armagh Observatory and Queen's University of Belfast i `I do not know what I may appear to the world, but to myself I seem to have been only like a boy playing on the sea-shore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me.'- Sir Isaac Newton In memory of my ancestors, Rao Bahadur Dr P K Warrier and Vaidyaratnam P S Varier, who were role models to our family in terms of excellence, ethics and etiquette Acknowledgements I wish to mention my special gratitude to: 1. David for his scientifically rigorous + socially composed discussions (academic as well as non-academic). Words remain futile to express how much I have learnt from this thorough gentleman in the last three years. 2. Mark for his time and patience during my sensical as well as nonsensical rants about various topics in astrophysics. I have always been amazed at his proficiency in diverse areas (unlike the super specialists these days!) of astronomy. 3. Tolis for his brainy as well as super witty remarks about research+other things in life. Good mathematician + fine comedian is a unique personality for sure :) Thanks for his time and suggestions to improve the thesis. 4. Jeremie for lots of helpful comments to improve my thesis. It has always been a pleasure to discuss science with him during many conferences. 5. Gavin for being my supportive and helpful second supervisor. Thanks very much. 6. Mihalis for his comments and guidance during QUB differentiation process. 7. Jorick for sparing his valuable time for being the independent chairman during the long four hour grilling :) 8. Gerry for the role of an excellent Observatory-QUB interface. 9. Simon for always actively involving during the talks and discussion meetings I led during the last 3 years. It has helped me to improve my grasp on fundamental princi- ples. 10. Stefano for some interesting insights into asteroidal geometry and orbits. 11. John Butler for the interesting conversations about cinema, politics, culture, trav- elling, music, science, books, nature, theatre etc. The list simply goes on. Recently I noticed that there is none in NI who does not know him :) Special thanks for allowing me to host many parties at his place. 12. James for interesting conversations on many legends in electromagnetism. 13. John McFarland for helping me in finding many papers and books. He is one of the quietest and calmest people I have ever met in my life.Time to replace His Holiness the Dalai Lama :) 14. Aileen for numerous visa support letters and prompt help in all paperwork. Her high efficiency is known to all. 15. Shane for assisting in everything concerning logistics. He has always been extra quick to help me. 16. Martin for installing various packages on the workstation and quickly resolving whenever I had any computing problem. i ii 17. Alison for the swift and efficient processing of all my travel claims. 18. Justyna for helping to keep our offices neat and tidy. 19. Terry for interesting discussions about various things related to astronomy and public outreach. 20. Miruna for being such a generous and kind host on numerous occasions. It is a well known fact in student circles that none can beat her in cooking and hospitality skills. 21. Gotz and Ding for all the jovial conversations inside and outside the observatory. 22. Alexey for letting me into that special list with whom he does not mind talking to :) 23. Maria for her super kind comments and wishes after viva. 24. quick witted Geert for motivating me to join the International Meteor Organization and the International Meteor Conference. Almost time for him to receive an OBE for his spontaneous jokes :) 25. ever cheerful Toby for all his sincere help before and after my arrival in Armagh. I wonder whether there is anyone as kind and organised as him when it comes to helping others. 26. Tom for the funny debates on cricket. I gather he is a celebrity in CA these days :) 27. Naslim for being such a special and helpful friend. 28. Shenghua for being my saviour in sharing meteor logging work. He was declared the official work genie of the observatory :) 29. Joachim for all the fun and frolic at his house parties, pubs, cinema, theatre, con- certs, road trips, ASGI etc . 30. Kamalam for all the help and support during my admission+visa formalities and while settling here. 31. Zhenghua for excellent games of badminton. Time for him to represent the Chinese team :) 32. Xianfei for lovely chinese food during parties. 33. Blagovest for being such an understanding and good hearted housemate. All resi- dents at 85 RWS have always made chaos in the solar system a reality :) 34. Tugca & Onur for being generous hosts for many movie and BBQ evenings. It was simply awesome to discuss about various movies and books with you. 35. Adam for the lovely road trips and a memorable ASGI at Birr Castle. Its been real fun to discuss a lot of particle physics. 36. Chris & Helen for putting up with my numerous whimsical conversations on sci- ence, arts and society when some of us were delightfully high :) One of the perfect couples I have ever met in my life. 37. Aaron for being a wonderful office mate. This poor chap must have been bored with my archaic and utopian ideas by now :) 38. Libby for being another jolly good office mate. Always a delight to converse with ever cheerful people like her. 39. Ruxy for interesting debates on religion. 40. Venu & Alex for their friendship. 41. Juie, Will and Yanina for their lovely thoughtful gift after my viva. A personalised bottle in my name from Bushmills distillery is a rare honour :) 42. Emma-Jane for organising the interesting workshops on some key government poli- cies. Good to be apprised of latest rules. 43. my summer student Ben for tolerating my rants about the great Halley as well as Evolution of Halley-type Comets and Meteoroid Streams iii comet Halley for one whole month :). Poor chap! Hope he remembers me when he becomes a great physicist in future. 44. International Student Support Office (especially Elaine) at QUB for all their timely help and advice regarding various paperwork concerning FCO, UKBA and Home Of- fice. 45. Planetarium staff for always being kind to waive my ticket fees without me request- ing at all. 46. Numerous interesting visitors like Colin, Eamon, Tony, Aurelie, Jonathan, Takuya, Dicle, Rebecca, James, Clara, Aurelien, Amy etc for fun evenings. 47. Incredibly large list (∼ several 102) of my friends and family members who sent me kind messages after the successful thesis defence. I was overwhelmed to put it mildly! 48. All the conference/meeting organisers and various embassies during 2010-2014 for all the travel, fun and learning. Thanksn! to all my previous supervisors Dr S B Gudennavar (during M.Phil), Prof G I Menon (during IAS summer project), Dr R L Hota (during M.Sc), Dr K C Ajith- prasad (during B.Sc). Sadly nothing can be done in today's world without money. I express my special thanks to the Department of Culture, Arts & Leisure of Northern Ireland for the gen- erous funding to pursue my research work. Only a pleasant childhood can lead to a happy life thereafter. As always I express my love and respect for my dad, mom, my beloved grandparents and some selected relatives who have been real angels to me whenever I was in happiness or sorrow. Last but not the least, these are the two fine minds who inspired me into science: Krishna Warrier (an epitome of brilliance and innocence) and Sashi Warrier (an incarnation of knowledge and wit). Life would not have been this way for me without both of you. Hence this thesis is fondly dedicated to my beloved Babumaman and Sashi uncle. Aswin Sekhar Space-time coordinates - (Armagh, 2014 Apr 28) Created with LATEX Evolution of Halley-type Comets and Meteoroid Streams Abstract The overall objective of the thesis is to understand the long term orbital dynamics of comets and meteoroid streams. The initial idea focused mainly on detailed analysis of Jovian resonances in Orionids and Leonids. Special emphasis was given to study their influence in causing meteor outbursts and storms on Earth. The theoretical simulations matched with observational records to a very good degree. This work led to the curious question as to whether any resonance mechanism could be driven due to Saturn's grav- ity. Subsequent analysis showed that Saturn's influences can also become vital when the order of resonance (concerning Saturn) is smaller than that in the adjacent Jovian resonances.
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