The Comet's Tale
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Publications and Products of April / avril 2005 Volume/volume 99 Number/numéro 2 [711] The Royal Astronomical Society of Canada Observer’s Calendar — 2005 The award-winning RASC Observer's Calendar is your annual guide Created by the Royal Astronomical Society of Canada and richly illustrated by photographs from leading amateur astronomers, the calendar pages are packed with detailed information including major lunar and planetary conjunctions, The Journal of the Royal Astronomical Society of Canada Le Journal de la Société royale d’astronomie du Canada meteor showers, eclipses, lunar phases, and daily Moonrise and Moonset times. Canadian and US holidays are highlighted. Perfect for home, office, or observatory. Individual Order Prices: $16.95 Cdn/ $13.95 US RASC members receive a $3.00 discount Shipping and handling not included. The Beginner’s Observing Guide Extensively revised and now in its fifth edition, The Beginner’s Observing Guide is for a variety of observers, from the beginner with no experience to the intermediate who would appreciate the clear, helpful guidance here available on an expanded variety of topics: constellations, bright stars, the motions of the heavens, lunar features, the aurora, and the zodiacal light. New sections include: lunar and planetary data through 2010, variable-star observing, telescope information, beginning astrophotography, a non-technical glossary of astronomical terms, and directions for building a properly scaled model of the solar system. Written by astronomy author and educator, Leo Enright; 200 pages, 6 colour star maps, 16 photographs, otabinding. Price: $19.95 plus shipping & handling. Skyways: Astronomy Handbook for Teachers Teaching Astronomy? Skyways Makes it Easy! Written by a Canadian for Canadian teachers and astronomy educators, Skyways is Canadian curriculum-specific; pre-tested by Canadian teachers; hands-on; interactive; geared for upper elementary, middle school, and junior-high grades; fun and easy to use; cost-effective. -
Using a Nuclear Explosive Device for Planetary Defense Against an Incoming Asteroid
Georgetown University Law Center Scholarship @ GEORGETOWN LAW 2019 Exoatmospheric Plowshares: Using a Nuclear Explosive Device for Planetary Defense Against an Incoming Asteroid David A. Koplow Georgetown University Law Center, [email protected] This paper can be downloaded free of charge from: https://scholarship.law.georgetown.edu/facpub/2197 https://ssrn.com/abstract=3229382 UCLA Journal of International Law & Foreign Affairs, Spring 2019, Issue 1, 76. This open-access article is brought to you by the Georgetown Law Library. Posted with permission of the author. Follow this and additional works at: https://scholarship.law.georgetown.edu/facpub Part of the Air and Space Law Commons, International Law Commons, Law and Philosophy Commons, and the National Security Law Commons EXOATMOSPHERIC PLOWSHARES: USING A NUCLEAR EXPLOSIVE DEVICE FOR PLANETARY DEFENSE AGAINST AN INCOMING ASTEROID DavidA. Koplow* "They shall bear their swords into plowshares, and their spears into pruning hooks" Isaiah 2:4 ABSTRACT What should be done if we suddenly discover a large asteroid on a collision course with Earth? The consequences of an impact could be enormous-scientists believe thatsuch a strike 60 million years ago led to the extinction of the dinosaurs, and something ofsimilar magnitude could happen again. Although no such extraterrestrialthreat now looms on the horizon, astronomers concede that they cannot detect all the potentially hazardous * Professor of Law, Georgetown University Law Center. The author gratefully acknowledges the valuable comments from the following experts, colleagues and friends who reviewed prior drafts of this manuscript: Hope M. Babcock, Michael R. Cannon, Pierce Corden, Thomas Graham, Jr., Henry R. Hertzfeld, Edward M. -
The Comet's Tale, and Therefore the Object As a Whole Would the Section Director Nick James Highlighted Have a Low Surface Brightness
1 Diebold Schilling, Disaster in connection with two comets sighted in 1456, Lucerne Chronicle, 1513 (Wikimedia Commons) THE COMET’S TALE Comet Section – British Astronomical Association Journal – Number 38 2019 June britastro.org/comet Evolution of the comet C/2016 R2 (PANSTARRS) along a total of ten days on January 2018. Composition of pictures taken with a zoom lens from Teide Observatory in Canary Islands. J.J Chambó Bris 2 Table of Contents Contents Author Page 1 Director’s Welcome Nick James 3 Section Director 2 Melvyn Taylor’s Alex Pratt 6 Observations of Comet C/1995 01 (Hale-Bopp) 3 The Enigma of Neil Norman 9 Comet Encke 4 Setting up the David Swan 14 C*Hyperstar for Imaging Comets 5 Comet Software Owen Brazell 19 6 Pro-Am José Joaquín Chambó Bris 25 Astrophotography of Comets 7 Elizabeth Roemer: A Denis Buczynski 28 Consummate Comet Section Secretary Observer 8 Historical Cometary Amar A Sharma 37 Observations in India: Part 2 – Mughal Empire 16th and 17th Century 9 Dr Reginald Denis Buczynski 42 Waterfield and His Section Secretary Medals 10 Contacts 45 Picture Gallery Please note that copyright 46 of all images belongs with the Observer 3 1 From the Director – Nick James I hope you enjoy reading this issue of the We have had a couple of relatively bright Comet’s Tale. Many thanks to Janice but diffuse comets through the winter and McClean for editing this issue and to Denis there are plenty of images of Buczynski for soliciting contributions. 46P/Wirtanen and C/2018 Y1 (Iwamoto) Thanks also to the section committee for in our archive. -
The State of Anthro–Earth
The Rosette Gazette Volume 22,, IssueIssue 7 Newsletter of the Rose City Astronomers July, 2010 RCA JULY 19 GENERAL MEETING The State Of Anthro–Earth THE STATE OF ANTHRO-EARTH: A Visitor From Far, Far Away Reviews the Status of Our Planet In This Issue: A Talk (in Earth-English) By Richard Brenne 1….General Meeting Enrico Fermi famously wondered why we hadn't heard from any other planetary 2….Club Officers civilizations, and Richard Brenne, who we'd always suspected was probably from another planet, thinks he might know the answer. Carl Sagan thought it was likely …...Magazines because those on other planets blew themselves up with nuclear weapons, but Richard …...RCA Library thinks its more likely that burning fossil fuels changed the climates and collapsed the 3….Local Happenings civilizations of those we might otherwise have heard from. Only someone from another planet could discuss this most serious topic with Richard's trademark humor 4…. Telescope (in a previous life he was an award-winning screenwriter - on which planet we're not Transformation sure) and bemused detachment. 5….Special Interest Groups Richard Brenne teaches a NASA-sponsored Global Climate Change class, serves on 6….Star Party Scene the American Meteorological Society's Committee to Communicate Climate Change, has written and produced documentaries about climate change since 1992, and has 7.…Observers Corner produced and moderated 50 hours of panel discussions about climate change with 18...RCA Board Minutes many of the world's top climate change scientists. Richard writes for the blog "Climate Progress" and his forthcoming book is titled "Anthro-Earth", his new name 20...Calendars for his adopted planet. -
CYANOGEN JETS and the ROTATION STATE of COMET MACHHOLZ (C/2004 Q2) Tony L
The Astronomical Journal, 133:2001Y2007, 2007 May # 2007. The American Astronomical Society. All rights reserved. Printed in U.S.A. CYANOGEN JETS AND THE ROTATION STATE OF COMET MACHHOLZ (C/2004 Q2) Tony L. Farnham1 Department of Astronomy, University of Maryland, College Park, MD 20742, USA; [email protected] Nalin H. Samarasinha2 National Optical Astronomy Observatory, Tucson, AZ 85719, USA; and Planetary Science Institute, Tucson, AZ 85719, USA Be´atrice E. A. Mueller1 Planetary Science Institute, Tucson, AZ 85719, USA and Matthew M. Knight1 Department of Astronomy, University of Maryland, College Park, MD 20742, USA Received 2006 June 16; accepted 2007 January 25 ABSTRACT Extensive observations of Comet Machholz (C/2004 Q2) from 2005 February, March, and April were used to derive a number of the properties of the comet’s nucleus. Images were obtained using narrowband comet filters to isolate the CN morphology. The images revealed two jets that pointed in roughly opposite directions relative to the nucleus and changed on hourly timescales. The morphology repeated itself in a periodic manner, and this fact was used to determine a rotation period for the nucleus of 17:60 Æ 0:05 hr. The morphology was also used to estimate a pole orientation of R:A: ¼ 50,decl: ¼þ35, and the jet source locations were found to be on opposite hemispheres at mid- latitudes. The longitudes are also about 180 apart, although this is not well constrained. The CN features were mea- sured to be moving at about 0.8 km sÀ1, which is close to the canonical value typically quoted for gas outflow. -
Comet Section Observing Guide
Comet Section Observing Guide 1 The British Astronomical Association Comet Section www.britastro.org/comet BAA Comet Section Observing Guide Front cover image: C/1995 O1 (Hale-Bopp) by Geoffrey Johnstone on 1997 April 10. Back cover image: C/2011 W3 (Lovejoy) by Lester Barnes on 2011 December 23. © The British Astronomical Association 2018 2018 December (rev 4) 2 CONTENTS 1 Foreword .................................................................................................................................. 6 2 An introduction to comets ......................................................................................................... 7 2.1 Anatomy and origins ............................................................................................................................ 7 2.2 Naming .............................................................................................................................................. 12 2.3 Comet orbits ...................................................................................................................................... 13 2.4 Orbit evolution .................................................................................................................................... 15 2.5 Magnitudes ........................................................................................................................................ 18 3 Basic visual observation ........................................................................................................ -
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. -
Planetary Defense: Near-Earth Objects, Nuclear Weapons, and International Law James A
Hastings International and Comparative Law Review Volume 42 Article 2 Number 1 Winter 2019 Winter 2019 Planetary Defense: Near-Earth Objects, Nuclear Weapons, and International Law James A. Green Follow this and additional works at: https://repository.uchastings.edu/ hastings_international_comparative_law_review Part of the Comparative and Foreign Law Commons, and the International Law Commons Recommended Citation James A. Green, Planetary Defense: Near-Earth Objects, Nuclear Weapons, and International Law, 42 Hastings Int'l & Comp.L. Rev. 1 (2019). Available at: https://repository.uchastings.edu/hastings_international_comparative_law_review/vol42/iss1/2 This Article is brought to you for free and open access by the Law Journals at UC Hastings Scholarship Repository. It has been accepted for inclusion in Hastings International and Comparative Law Review by an authorized editor of UC Hastings Scholarship Repository. Planetary Defense: Near-Earth Objects, Nuclear Weapons, and International Law BY JAMES A. GREEN ABSTRACT The risk of a large Near-Earth Object (NEO), such as an asteroid, colliding with the Earth is low, but the consequences of that risk manifesting could be catastrophic. Recent years have witnessed an unprecedented increase in global political will in relation to NEO preparedness, following the meteoroid impact in Chelyabinsk, Russia in 2013. There also has been an increased focus amongst states on the possibility of using nuclear detonation to divert or destroy a collision- course NEO—something that a majority of scientific opinion now appears to view as representing humanity’s best, or perhaps only, option in extreme cases. Concurrently, recent developments in nuclear disarmament and the de-militarization of space directly contradict the proposed “nuclear option” for planetary defense. -
Detecting the Yarkovsky Effect Among Near-Earth Asteroids From
Detecting the Yarkovsky effect among near-Earth asteroids from astrometric data Alessio Del Vignaa,b, Laura Faggiolid, Andrea Milania, Federica Spotoc, Davide Farnocchiae, Benoit Carryf aDipartimento di Matematica, Universit`adi Pisa, Largo Bruno Pontecorvo 5, Pisa, Italy bSpace Dynamics Services s.r.l., via Mario Giuntini, Navacchio di Cascina, Pisa, Italy cIMCCE, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universits, UPMC Univ. Paris 06, Univ. Lille, 77 av. Denfert-Rochereau F-75014 Paris, France dESA SSA-NEO Coordination Centre, Largo Galileo Galilei, 1, 00044 Frascati (RM), Italy eJet Propulsion Laboratory/California Institute of Technology, 4800 Oak Grove Drive, Pasadena, 91109 CA, USA fUniversit´eCˆote d’Azur, Observatoire de la Cˆote d’Azur, CNRS, Laboratoire Lagrange, Boulevard de l’Observatoire, Nice, France Abstract We present an updated set of near-Earth asteroids with a Yarkovsky-related semi- major axis drift detected from the orbital fit to the astrometry. We find 87 reliable detections after filtering for the signal-to-noise ratio of the Yarkovsky drift esti- mate and making sure the estimate is compatible with the physical properties of the analyzed object. Furthermore, we find a list of 24 marginally significant detec- tions, for which future astrometry could result in a Yarkovsky detection. A further outcome of the filtering procedure is a list of detections that we consider spurious because unrealistic or not explicable with the Yarkovsky effect. Among the smallest asteroids of our sample, we determined four detections of solar radiation pressure, in addition to the Yarkovsky effect. As the data volume increases in the near fu- ture, our goal is to develop methods to generate very long lists of asteroids with reliably detected Yarkovsky effect, with limited amounts of case by case specific adjustments. -
Properties of Cometary Nuclei
Properties of Cometary Nuclei J, Rahe, NASA Headquarters, Washington, DC V. Vanysek, Charles University, Prague, Czech Republic P. R. Weissman Jet Propulsion Laboratory, Pasadena, CA Abstract: Active long- and short-period comets contribute about 20 to 30% of the major impactors on the Earth. Cometary nuclei are irregular bodies, typically a few to ten kilometers in diameter, with masses in the range 10*5 to 10’8 g. The nuclei are composed of an intimate mixture of volatile ices, mostly water ice, and hydrocarbon and silicate grains. The composition is the closest to solar composition of any known bodies in the solar system. The nuclei appear to be weakly bonded agglomerations of smaller icy planetesimals, and material strengths estimated from observed tidal disruption events are fairly low, typically 1& to ld N m-2. Density estimates range between 0.2 and 1.2 g cm-3 but are very poorly determined, if at all. As comets age they develop nonvolatile crusts on their surfaces which eventually render them inactive, similar in appearance to carbonaceous asteroids. However, dormant comets may continue to show sporadic activity and outbursts for some time before they become truly extinct. The source of the long-period comets is the Oort cloud, a vast spherical cloud of perhaps 1012 to 10’3 comets surrounding the solar system and extending to interstellar distances. The likely source of the short-period comets is the Kuiper belt, a ring of perhaps 108 to 1010 remnant icy planetesimals beyond the orbit of Neptune, though some short-period comets may also be long- pcriod comets from the Oort cloud which have been perturbed to short-period orbits. -
Arxiv:1011.4313V1
Accepted to ApJ: October 23, 2010 GALEX FUV Observations of Comet C/2004 Q2 (Machholz): The Ionization Lifetime of Carbon Jeffrey P. Morgenthaler Planetary Science Institute, 1700 E. Fort Lowell, Ste 106, Tucson, AZ 85719, USA [email protected] Walter M. Harris Department of Applied Sciences, University of California at Davis, One Shields Ave., Davis, CA 95616, USA Michael R. Combi Department of Atmospheric, Oceanic and Space Sciences, The University of Michigan, 2455 Hayward St. Ann Arbor, MI 48109, Ann Arbor, MI, USA Paul D. Feldman Department of Physics and Astronomy, The Johns Hopkins University Charles and 34th Streets, Baltimore, Maryland 21218, USA Harold A. Weaver Space Department, Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723-6099, USA ABSTRACT 3 arXiv:1011.4313v1 [astro-ph.EP] 18 Nov 2010 We present a measurement of the lifetime of ground state atomic carbon, C( P), against ionization processes in interplanetary space and compare it to the lifetime ex- pected from the dominant physical processes likely to occur in this medium. Our mea- surement is based on analysis of a far ultraviolet (FUV) image of comet C/2004 Q2 (Machholz) recorded by the Galaxy Evolution Explorer (GALEX) on 2005 March 1. The bright C I 1561 A˚ and 1657 A˚ multiplets dominate the GALEX FUV band. We used the image to create high signal-to-noise ratio radial profiles that extended beyond 1×106 km from the comet nucleus. Our measurements yielded a total carbon lifetime of 7.1 – 9.6×105 s (ionization rate of 1.0 – 1.4×10−6 s−1) when scaled to 1 AU. -
The National Aeronautics and Space Administration Planetary Astronomy Program
FRS 347320 FINAL REPORT FOR GRANT NAG5-3938 SUBMITTED TO: The National Aeronautics and Space Administration Planetary Astronomy Program TITLE: Beginning Research with the 1.8-meter Spacewatch Telescope ORGANIZATION: The University of Arizona Lunar and Planetary Laboratory PERIOD OF GRANT: 1996 Dec. 1 - 2000 Nov. 30 PERIOD REPORTED ON: 1996 Dec. I - 2001 Feb. 9 2._o[ PRINCIPAL INVESTIGATOR: Tom Gehrels Date Professor Lunar and Planetary Laboratory University of Arizona Kuiper Space Sciences Building 1629 East University Boulevard Tucson, AZ 85721-0092 Phone: 520/621-6970 FAX: 520/621-1940 Email: [email protected] BUSINESS REPRESENTATIVE: Ms. Lynn A. Lane Senior Business Manager Lunar and Planetary Laboratory University of Arizona Kuiper Space Sciences Building 1629 East University Boulevard Tucson, AZ 85721-0092 Phone: 520/621-6966 FAX: 520/621-4933 Email: [email protected] c:_w_nnsaknag53938.fnl Participating Professionals (all at the Lunar and Planetary Laboratory): Terrence H. Bressi (B. S., Astron. & Physics) Engineer Anne S. Descour (M. S., Computer Science) Senior Systems Programmer Tom Gehrels (Ph. D., Astronomy) Professor, observer, and PI Robert Jedicke (Ph.D., Physics) Principal Research Specialist Jeffrey A. Larsen (Ph. D., Astronomy) Principal Research Specialist and observer Robert S. McMiUan (Ph.D., Astronomy) Associate Research Scientist & observer Joseph L. Montani (M. S., Astronomy) Senior Research Specialist and observer Marcus L. Perry (B. A., Astronomy) (Chief) Staff Engineer James V. Scotti (B. S., Astronomy) Senior Research Specialist and observer PROJECT SUMMARY The purpose of this grant was to bring the Spacewatch 1.8-m telescope to operational status for research on asteroids and comets.