DOCSLIB.ORG

Evolution of Halley-Type Comets and Meteoroid Streams

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Evolution of Halley-Type Comets and Meteoroid Streams 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.
Load more

Recommended publications
  • The Minor Planet Bulletin
    THE MINOR PLANET BULLETIN OF THE MINOR PLANETS SECTION OF THE BULLETIN ASSOCIATION OF LUNAR AND PLANETARY OBSERVERS VOLUME 36, NUMBER 3, A.D. 2009 JULY-SEPTEMBER 77. PHOTOMETRIC MEASUREMENTS OF 343 OSTARA Our data can be obtained from http://www.uwec.edu/physics/ AND OTHER ASTEROIDS AT HOBBS OBSERVATORY asteroid/. Lyle Ford, George Stecher, Kayla Lorenzen, and Cole Cook Acknowledgements Department of Physics and Astronomy University of Wisconsin-Eau Claire We thank the Theodore Dunham Fund for Astrophysics, the Eau Claire, WI 54702-4004 National Science Foundation (award number 0519006), the [email protected] University of Wisconsin-Eau Claire Office of Research and Sponsored Programs, and the University of Wisconsin-Eau Claire (Received: 2009 Feb 11) Blugold Fellow and McNair programs for financial support. References We observed 343 Ostara on 2008 October 4 and obtained R and V standard magnitudes. The period was Binzel, R.P. (1987). “A Photoelectric Survey of 130 Asteroids”, found to be significantly greater than the previously Icarus 72, 135-208. reported value of 6.42 hours. Measurements of 2660 Wasserman and (17010) 1999 CQ72 made on 2008 Stecher, G.J., Ford, L.A., and Elbert, J.D. (1999). “Equipping a March 25 are also reported. 0.6 Meter Alt-Azimuth Telescope for Photometry”, IAPPP Comm, 76, 68-74. We made R band and V band photometric measurements of 343 Warner, B.D. (2006). A Practical Guide to Lightcurve Photometry Ostara on 2008 October 4 using the 0.6 m “Air Force” Telescope and Analysis. Springer, New York, NY. located at Hobbs Observatory (MPC code 750) near Fall Creek, Wisconsin.
    [Show full text]
  • Michael Kühn Detlev Auvermann RARE BOOKS
    ANTIQUARIAT 55Michael Kühn Detlev Auvermann RARE BOOKS 1 Rolfinck’s copy ALESSANDRINI, Giulio. De medicina et medico dialogus, libris quinque distinctus. Zurich, Andreas Gessner, 1557. 4to, ff. [6], pp. AUTOLYKOS (AUTOLYCUS OF PYTANE). 356, ff. [8], with printer’s device on title and 7 woodcut initials; a few annotations in ink to the text; a very good copy in a strictly contemporary binding of blind-stamped pigskin, the upper cover stamped ‘1557’, red Autolyci De vario ortu et occasu astrorum inerrantium libri dvo nunc primum de graeca lingua in latinam edges, ties lacking; front-fly almost detached; contemporary ownership inscription of Werner Rolfinck on conuersi … de Vaticana Bibliotheca deprompti. Josepho Avria, neapolitano, interprete. Rome, Vincenzo title (see above), as well as a stamp and duplicate stamp of Breslau University library. Accolti, 1588. 4to, ff. [6], pp. 70, [2]; with large woodcut device on title, and several woodcut diagrams in the text; title a little browned, else a fine copy in 19th-century vellum-backed boards, new endpapers. EUR 3.800.- EUR 4.200.- First edition of Alessandrini’s medical dialogues, his most famous publication and a work of rare erudition. Very rare Latin edition, translated from a Greek manuscript at the Autolycus was a Greek mathematician and astronomer, who probably Giulio Alessandrini (or Julius Alexandrinus de Neustein) (1506–1590) was an Italian physician and author Vatican library, of Autolycus’ work on the rising and setting of the fixed flourished in the second half of the 4th century B.C., since he is said to of Trento who studied philosophy and medicine at the University of Padua, then mathematical science, stars.
    [Show full text]
  • The Comet's Tale
    THE COMET’S TALE Journal of the Comet Section of the British Astronomical Association Number 33, 2014 January Not the Comet of the Century 2013 R1 (Lovejoy) imaged by Damian Peach on 2013 December 24 using 106mm F5. STL-11k. LRGB. L: 7x2mins. RGB: 1x2mins. Today’s images of bright binocular comets rival drawings of Great Comets of the nineteenth century. Rather predictably the expected comet of the century Contents failed to materialise, however several of the other comets mentioned in the last issue, together with the Comet Section contacts 2 additional surprise shown above, put on good From the Director 2 appearances. 2011 L4 (PanSTARRS), 2012 F6 From the Secretary 3 (Lemmon), 2012 S1 (ISON) and 2013 R1 (Lovejoy) all Tales from the past 5 th became brighter than 6 magnitude and 2P/Encke, 2012 RAS meeting report 6 K5 (LINEAR), 2012 L2 (LINEAR), 2012 T5 (Bressi), Comet Section meeting report 9 2012 V2 (LINEAR), 2012 X1 (LINEAR), and 2013 V3 SPA meeting - Rob McNaught 13 (Nevski) were all binocular objects. Whether 2014 will Professional tales 14 bring such riches remains to be seen, but three comets The Legacy of Comet Hunters 16 are predicted to come within binocular range and we Project Alcock update 21 can hope for some new discoveries. We should get Review of observations 23 some spectacular close-up images of 67P/Churyumov- Prospects for 2014 44 Gerasimenko from the Rosetta spacecraft. 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 221482 (W) Fax: (+44) (0)1223 221279 (W) 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.
    [Show full text]
  • Aqueous Alteration on Main Belt Primitive Asteroids: Results from Visible Spectroscopy1
    Aqueous alteration on main belt primitive asteroids: results from visible spectroscopy1 S. Fornasier1,2, C. Lantz1,2, M.A. Barucci1, M. Lazzarin3 1 LESIA, Observatoire de Paris, CNRS, UPMC Univ Paris 06, Univ. Paris Diderot, 5 Place J. Janssen, 92195 Meudon Pricipal Cedex, France 2 Univ. Paris Diderot, Sorbonne Paris Cit´e, 4 rue Elsa Morante, 75205 Paris Cedex 13 3 Department of Physics and Astronomy of the University of Padova, Via Marzolo 8 35131 Padova, Italy Submitted to Icarus: November 2013, accepted on 28 January 2014 e-mail: [email protected]; fax: +33145077144; phone: +33145077746 Manuscript pages: 38; Figures: 13 ; Tables: 5 Running head: Aqueous alteration on primitive asteroids Send correspondence to: Sonia Fornasier LESIA-Observatoire de Paris arXiv:1402.0175v1 [astro-ph.EP] 2 Feb 2014 Batiment 17 5, Place Jules Janssen 92195 Meudon Cedex France e-mail: [email protected] 1Based on observations carried out at the European Southern Observatory (ESO), La Silla, Chile, ESO proposals 062.S-0173 and 064.S-0205 (PI M. Lazzarin) Preprint submitted to Elsevier September 27, 2018 fax: +33145077144 phone: +33145077746 2 Aqueous alteration on main belt primitive asteroids: results from visible spectroscopy1 S. Fornasier1,2, C. Lantz1,2, M.A. Barucci1, M. Lazzarin3 Abstract This work focuses on the study of the aqueous alteration process which acted in the main belt and produced hydrated minerals on the altered asteroids. Hydrated minerals have been found mainly on Mars surface, on main belt primitive asteroids and possibly also on few TNOs. These materials have been produced by hydration of pristine anhydrous silicates during the aqueous alteration process, that, to be active, needed the presence of liquid water under low temperature conditions (below 320 K) to chemically alter the minerals.
    [Show full text]
  • The Minor Planet Bulletin 37 (2010) 45 Classification for 244 Sita
    THE MINOR PLANET BULLETIN OF THE MINOR PLANETS SECTION OF THE BULLETIN ASSOCIATION OF LUNAR AND PLANETARY OBSERVERS VOLUME 37, NUMBER 2, A.D. 2010 APRIL-JUNE 41. LIGHTCURVE AND PHASE CURVE OF 1130 SKULD Robinson (2009) from his data taken in 2002. There is no evidence of any change of (V-R) color with asteroid rotation. Robert K. Buchheim Altimira Observatory As a result of the relatively short period of this lightcurve, every 18 Altimira, Coto de Caza, CA 92679 (USA) night provided at least one minimum and maximum of the [email protected] lightcurve. The phase curve was determined by polling both the maximum and minimum points of each night’s lightcurve. Since (Received: 29 December) The lightcurve period of asteroid 1130 Skuld is confirmed to be P = 4.807 ± 0.002 h. Its phase curve is well-matched by a slope parameter G = 0.25 ±0.01 The 2009 October-November apparition of asteroid 1130 Skuld presented an excellent opportunity to measure its phase curve to very small solar phase angles. I devoted 13 nights over a two- month period to gathering photometric data on the object, over which time the solar phase angle ranged from α = 0.3 deg to α = 17.6 deg. All observations used Altimira Observatory’s 0.28-m Schmidt-Cassegrain telescope (SCT) working at f/6.3, SBIG ST- 8XE NABG CCD camera, and photometric V- and R-band filters. Exposure durations were 3 or 4 minutes with the SNR > 100 in all images, which were reduced with flat and dark frames.
    [Show full text]
  • Mpc 20051215
    2005 DEC. 15 M.P.C. 55685 The MINOR PLANET CIRCULARS/MINOR PLANETS AND COMETS are published, on behalf of Commission 20 of the International Astronomical Union, usually in batches on or near the date of each full moon, by: Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. [email protected] or FAX 617{495{7231 (subscriptions) [email protected] (science) Phone 617{495{7244/7444/7440/7273 (for emergency use only). World-Wide Web address http://cfa-www.harvard.edu/iau/mpc.html ISSN 0736-6884 Brian G. Marsden, Director Gareth V. Williams, Associate Director Timothy B. Spahr, NEO Technical Specialist Syuichi Nakano, Andreas Doppler and Kyle E. Smalley, Associates Supported in part by the Brinson and TABASGO Foundations c Copyright 2005 Minor Planet Center Prepared using the Tamkin Foundation Computer Network ° EDITORIAL NOTICE 147 Osservatorio Astron¶omico di Suno. Observers L. Buzzi, D. Crespi, S. Foglia, G. Galli, S. Minuto, V. Sacco. Measurers L. Buzzi, S. Foglia, G. Galli, The Minor Planet Center is pleased to acknowledge with thanks another gen- S. Minuto. 0.40-m /4 reflector + CCD. erous donation from F. K. Edmondson (Bloomington, IN; senior former president of f 170 Observatorio de Begues. Observer J. Manteca. 0.36-m /10 Schmidt- IAU Commission 20). f Cassegrain + CCD. The next batch of Minor Planet Circulars will be issued on or about 2006 Feb. 201 Jonathan B. Postel Observatory. Observer V. Pozzoli. 0.30-m f/10 reflector 13. There will be no Circulars during January. + CCD. 204 Schiaparelli Observatory. Observer L.
    [Show full text]
  • Kosmos, and Uranus
    K O 2 M O 2 : A General £>urbep OF THE PHYSICAL PHENOMENA OF THE UNIVERSE. BY ALEXANDER VON HUMBOLDT. Vol. I. Natune vero rerum vis atque majestaa in omnibus moment is fide caret, si quia modo partes ejus ac non totam compiectatur animo. Pi- in., Hist. Nat. lib. yH. cap. 1. LONDON: HIPPOLYTE BAILLIERE, PUBLISHER, AND FOREIGN BOOKSELLER, 219, REGENT STREET. 1845. TCI HIS MAJESTY THE KING OF PRUSSIA, FREDERICK-WILLIAM IV, THIS SURVEY OF THE PHYSICAL HISTORY OF THE UNIVERSE, 3Jg Betifcatrti, WITH FEELINGS OF DEEP RESPECT AND HEARTFELT GRATITUDE, BY ALEXANDER von HUMBOLDT. PREFACE. In the evening of a long and active life, I present the public with a work the indefinite outlines of which have floated in my mind for almost half a century. I have, in many moods, regarded this work as impracticable; and when I had abandoned it, have still, rashly perhaps, returned to it again. — I lay it before my contemporaries with the diffidence which a reasonable mistrust in the measure ^of my abilities inspires. I also endeavour to forget, that works long looked for are commonly less indulgently received. If circumstances, and an irresistible propensity to pur sue science of various kinds, led me to devote myself for many years, and almost exclusively as it seemed, to parti cular branches, — to descriptive botany, geology, chemistry, astronomical observation and terrestrial magnetism, — as preparatives for a journey on a great scale, the special purpose of my studies was always one still higher than this. My main object was to prepare myself to compre Vlll PREFACE.
    [Show full text]
  • The Minor Planet Bulletin 36, 188-190
    THE MINOR PLANET BULLETIN OF THE MINOR PLANETS SECTION OF THE BULLETIN ASSOCIATION OF LUNAR AND PLANETARY OBSERVERS VOLUME 37, NUMBER 3, A.D. 2010 JULY-SEPTEMBER 81. ROTATION PERIOD AND H-G PARAMETERS telescope (SCT) working at f/4 and an SBIG ST-8E CCD. Baker DETERMINATION FOR 1700 ZVEZDARA: A independently initiated observations on 2009 September 18 at COLLABORATIVE PHOTOMETRY PROJECT Indian Hill Observatory using a 0.3-m SCT reduced to f/6.2 coupled with an SBIG ST-402ME CCD and Johnson V filter. Ronald E. Baker Benishek from the Belgrade Astronomical Observatory joined the Indian Hill Observatory (H75) collaboration on 2009 September 24 employing a 0.4-m SCT PO Box 11, Chagrin Falls, OH 44022 USA operating at f/10 with an unguided SBIG ST-10 XME CCD. [email protected] Pilcher at Organ Mesa Observatory carried out observations on 2009 September 30 over more than seven hours using a 0.35-m Vladimir Benishek f/10 SCT and an unguided SBIG STL-1001E CCD. As a result of Belgrade Astronomical Observatory the collaborative effort, a total of 17 time series sessions was Volgina 7, 11060 Belgrade 38 SERBIA obtained from 2009 August 20 until October 19. All observations were unfiltered with the exception of those recorded on September Frederick Pilcher 18. MPO Canopus software (BDW Publishing, 2009a) employing 4438 Organ Mesa Loop differential aperture photometry, was used by all authors for Las Cruces, NM 88011 USA photometric data reduction. The period analysis was performed using the same program. David Higgins Hunter Hill Observatory The data were merged by adjusting instrumental magnitudes and 7 Mawalan Street, Ngunnawal ACT 2913 overlapping characteristic features of the individual lightcurves.
    [Show full text]
  • The Minor Planet Bulletin Lost a Friend on Agreement with That Reported by Ivanova Et Al
    THE MINOR PLANET BULLETIN OF THE MINOR PLANETS SECTION OF THE BULLETIN ASSOCIATION OF LUNAR AND PLANETARY OBSERVERS VOLUME 33, NUMBER 3, A.D. 2006 JULY-SEPTEMBER 49. LIGHTCURVE ANALYSIS FOR 19848 YEUNGCHUCHIU Kwong W. Yeung Desert Eagle Observatory P.O. Box 105 Benson, AZ 85602 [email protected] (Received: 19 Feb) The lightcurve for asteroid 19848 Yeungchuchiu was measured using images taken in November 2005. The lightcurve was found to have a synodic period of 3.450±0.002h and amplitude of 0.70±0.03m. Asteroid 19848 Yeungchuchiu was discovered in 2000 Oct. by the author at Desert Beaver Observatory, AZ, while it was about one degree away from Jupiter. It is named in honor of my father, The amplitude of 0.7 magnitude indicates that the long axis is Yeung Chu Chiu, who is a businessman in Hong Kong. I hoped to about 2 times that of the shorter axis, as seen from the line of sight learn the art of photometry by studying the lightcurve of 19848 as at that particular moment. Since both the maxima and minima my first solo project. have similar “height”, it’s likely that the rotational axis was almost perpendicular to the line of sight. Using a remote 0.46m f/2.8 reflector and Apogee AP9E CCD camera located in New Mexico Skies (MPC code H07), images of Many amateurs may have the misconception that photometry is a the asteroid were obtained on the nights of 2005 Nov. 20 and 21. very difficult science. After this learning exercise I found that, at Exposures were 240 seconds.
    [Show full text]
  • Implications of Magnitude Distribution Comparisons Between Trans-Neptunian Objects and Comets
    Implications of Magnitude Distribution Comparisons between Trans-Neptunian Objects and Comets by Alexander J. Willman, Jr. SpSt 997 “Independent Study” Department of Space Studies University of North Dakota Dr. C. A. Wood, Advisor December 1, 1995 Implications of Magnitude Distribution Comparisons between Trans-Neptunian Objects and Comets Abstract The population of observed trans-neptunian objects has a fairly well-defined magnitude distribution, however, the population of observed short-period comets does not. This analysis of the population distributions of observed trans-neptunian objects (TNOs) and short-period comets (SPCs) indicates that the observed number of TNOs and SPCs is insufficient to judge conclusively whether the trans-neptunian objects are related to the short-period comets or whether the TNOs are part of the Kuiper belt from which the SPCs are believed to be derived. Differences in the population distributions of TNOs and SPCs indicate that the TNOs are not representative of the Kuiper belt as a whole, even if they are part of the Kuiper belt. Further analysis of the population distributions of comets and the TNOs has provided additional information and some predictions about the populations’ characteristics. This derived information includes the facts that: the six brightest SPCs for which H10 magnitudes have been calculated likely belong to the Oort cloud population (long-period) of comets instead of the Kuiper belt population of comets; Pluto and Charon are likely to belong to the TNO population instead of the major planet population; there are likely to be ~109 TNOs in the Kuiper belt, including many Pluto-sized objects, massing a total of ~1025 kg in all.
    [Show full text]
  • The Comet's Tale
    THE COMET’S TALE Newsletter of the Comet Section of the British Astronomical Association Volume 8, No 2 (Issue 16), 2001 October DEEP SPACE 1 ENCOUNTERS 19P/Borrelly problem. All the science data ten years to facilitate the five Donald K. Yeomans were successfully received on upcoming cometary encounters Earth within a few hours after the provided by the CONTOUR, NASA/JPL, Near-Earth Object flyby itself. The DS1 spacecraft Stardust, Deep Impact, and program office was designed to test various space Rosetta spacecraft. technologies including the ion On Saturday evening at 7:00 PM, drive engine that first ionizes For more information, see: sustained applause broke out in xenon and then electrostatically the Deep Space 1 spacecraft accelerated these charged http://nmp.jpl.nasa.gov/ds1/ control room at the Jet Propulsion particles to form a modest, but Laboratory. The first high continuous, rocket thrust. resolution images of comet's Borrelly nucleus had reached Earth (Figure 1). The images were sharper than expected and revealed a very dark, outgasing nucleus shaped a bit like a bowling pin except this bowling pin was nearly the size of Mt. Everest. Examination of the surface features reveals ridges, fault lines, and bright areas that are thought to be source regions for the nucleus' jets that emanate toward the solar direction. These Figure 2 This image of comet jets are thought to be the vaporization of the comet's ices as Borrelly's nucleus has been the active regions are heated by Figure 1 This black and white purposely overexposed to show sunlight (Figure 2).
    [Show full text]
  • The Astronomer Magazine Index
    The Astronomer Magazine Index The numbers in brackets indicate approx lengths in pages (quarto to 1982 Aug, A4 afterwards) 1964 May p1-2 (1.5) Editorial (Function of CA) p2 (0.3) Retrospective meeting after 2 issues : planned date p3 (1.0) Solar Observations . James Muirden , John Larard p4 (0.9) Domes on the Mare Tranquillitatis . Colin Pither p5 (1.1) Graze Occultation of ZC620 on 1964 Feb 20 . Ken Stocker p6-8 (2.1) Artificial Satellite magnitude estimates : Jan-Apr . Russell Eberst p8-9 (1.0) Notes on Double Stars, Nebulae & Clusters . John Larard & James Muirden p9 (0.1) Venus at half phase . P B Withers p9 (0.1) Observations of Echo I, Echo II and Mercury . John Larard p10 (1.0) Note on the first issue 1964 Jun p1-2 (2.0) Editorial (Poor initial response, Magazine name comments) p3-4 (1.2) Jupiter Observations . Alan Heath p4-5 (1.0) Venus Observations . Alan Heath , Colin Pither p5 (0.7) Remarks on some observations of Venus . Colin Pither p5-6 (0.6) Atlas Coeli corrections (5 stars) . George Alcock p6 (0.6) Telescopic Meteors . George Alcock p7 (0.6) Solar Observations . John Larard p7 (0.3) R Pegasi Observations . John Larard p8 (1.0) Notes on Clusters & Double Stars . John Larard p9 (0.1) LQ Herculis bright . George Alcock p10 (0.1) Observations of 2 fireballs . John Larard 1964 Jly p2 (0.6) List of Members, Associates & Affiliations p3-4 (1.1) Editorial (Need for more members) p4 (0.2) Summary of June 19 meeting p4 (0.5) Exploding Fireball of 1963 Sep 12/13 .
    [Show full text]