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On the Origin and Evolution of the Material in 67P/Churyumov-Gerasimenko
On the Origin and Evolution of the Material in 67P/Churyumov-Gerasimenko Martin Rubin, Cécile Engrand, Colin Snodgrass, Paul Weissman, Kathrin Altwegg, Henner Busemann, Alessandro Morbidelli, Michael Mumma To cite this version: Martin Rubin, Cécile Engrand, Colin Snodgrass, Paul Weissman, Kathrin Altwegg, et al.. On the Origin and Evolution of the Material in 67P/Churyumov-Gerasimenko. Space Sci.Rev., 2020, 216 (5), pp.102. 10.1007/s11214-020-00718-2. hal-02911974 HAL Id: hal-02911974 https://hal.archives-ouvertes.fr/hal-02911974 Submitted on 9 Dec 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Space Sci Rev (2020) 216:102 https://doi.org/10.1007/s11214-020-00718-2 On the Origin and Evolution of the Material in 67P/Churyumov-Gerasimenko Martin Rubin1 · Cécile Engrand2 · Colin Snodgrass3 · Paul Weissman4 · Kathrin Altwegg1 · Henner Busemann5 · Alessandro Morbidelli6 · Michael Mumma7 Received: 9 September 2019 / Accepted: 3 July 2020 / Published online: 30 July 2020 © The Author(s) 2020 Abstract Primitive objects like comets hold important information on the material that formed our solar system. Several comets have been visited by spacecraft and many more have been observed through Earth- and space-based telescopes. -
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 ........................................................................................................ -
Polarimetry of Comets: Observational Results and Problems
POLARIMETRY OF COMETS: OBSERVATIONAL RESULTS AND PROBLEMS N. Kiselev & V. Rosenbush Main Astronomical Observatory of National Academy of Sciences of Ukraine 1st WG meeting in Warsaw, Poland, 7-9 May 2012 Outline of presentation Linear polarization of comets. Problems with the interpretation of diversity in the maximum polarization of comets. Circular polarization of comets. Next task Polarimetric data for comets up to the mid 1970s (Kiselev, 1981; Dobrovolsky et al.,1986) The polarization of molecular emissions was explained as being due to resonance fluorescence (Öhman, 1941; Le Borgne et al., 1986) 2 P90 sin P() 2 , where P90 = 0.077 1 P90 cos Curve (2) is polarization phase dependence for the resonance fluorescence according to Öhman’s formula. Curve (1) is a fit of polarization data in continuum according to Öhman’s formula. There are no observations of comets at phase angles smaller than 40 until 1975. Open questions: •What is polarization phase curve for dust near opposition ? •What is the maximum of polarization? •Is there a diversity in comet polarization? Comets: negative polarization branch Discovery of the NPB gave impetus to development of new optical mechanisms Observations of comet West to explain its origin. Among them, the revealed a negative branch of scattering of light by particles with aggregate structure. linear polarization at phase angles 22. (Kiselev&Chernova, 1976) Phase angle dependence of polarization for comets in the blue and red continuum (Kiselev, 2003) The observed difference in the All comets polarization of the two groups of comets is apparent. Why is this? There are three points of view: •The polarization of each comet is an individual (Perrin&Lamy, 1986). -
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. -
The Composition of Cometary Volatiles 391
Bockelée-Morvan et al.: The Composition of Cometary Volatiles 391 The Composition of Cometary Volatiles D. Bockelée-Morvan and J. Crovisier Observatoire de Paris M. J. Mumma NASA Goddard Space Flight Center H. A. Weaver The Johns Hopkins University Applied Physics Laboratory The composition of cometary ices provides key information on the chemical and physical properties of the outer solar nebula where comets formed, 4.6 G.y. ago. This chapter summa- rizes our current knowledge of the volatile composition of cometary nuclei, based on spectro- scopic observations and in situ measurements of parent molecules and noble gases in cometary comae. The processes that govern the excitation and emission of parent molecules in the radio, infrared (IR), and ultraviolet (UV) wavelength regions are reviewed. The techniques used to convert line or band fluxes into molecular production rates are described. More than two dozen parent molecules have been identified, and we describe how each is investigated. The spatial distribution of some of these molecules has been studied by in situ measurements, long-slit IR and UV spectroscopy, and millimeter wave mapping, including interferometry. The spatial dis- tributions of CO, H2CO, and OCS differ from that expected during direct sublimation from the nucleus, which suggests that these species are produced, at least partly, from extended sources in the coma. Abundance determinations for parent molecules are reviewed, and the evidence for chemical diversity among comets is discussed. 1. INTRODUCTION ucts are called daughter products. Although there have been in situ measurements of some parent molecules in the coma Much of the scientific interest in comets stems from their of 1P/Halley using mass spectrometers, the majority of re- potential role in elucidating the processes responsible for the sults on the parent molecules have been derived from remote formation and evolution of the solar system. -
Ice & Stone 2020
Ice & Stone 2020 WEEK 21: MAY 17-23 Presented by The Earthrise Institute # 21 Authored by Alan Hale This week in history MAY 17 18 19 20 21 22 23 MAY 17, 1882: Observers in the path of a total solar eclipse that crossed central Egypt see and photograph a bright comet during totality. Comet Tewfik X/1882 K1, which was never seen again, was an apparent Kreutz sungrazer, and is this week’s “Comet of the Week.” Solar eclipse comets, in general, are the subject of this week’s “Special Topics” presentation. MAY 17 18 19 20 21 22 23 MAY 18, 44 B.C.: Astronomers in China first record seeing a bright comet, which was also later seen from Europe. The comet’s appearance shortly after the assassination of Julius Caesar has caused it to become generally known as “Caesar’s Comet” and it is next week’s “Comet of the Week.” MAY 18, 1970: Australian amateur astronomer Graeme White discovers a bright comet deep in evening twilight. Over the next several nights several other independent discoveries of this comet were made, including by Air France pilot Emilio Ortiz and by Carlos Bolelli at Cerro Tololo Inter-American Observatory in Chile. Comet White-Ortiz-Bolelli 1970f was the last bright Kreutz sungrazer to be observed from the ground until 2011. Kreutz sungrazers are the subject of a future “Special Topics” presentation. MAY 17 18 19 20 21 22 23 MAY 20, 1910: Comet 1P/Halley passes 0.151 AU from Earth, transiting the sun in the process (which was not detected) and briefly creating the longest apparent cometary tail ever observed. -
Ice & Stone 2020
Ice & Stone 2020 WEEK 17: APRIL 19-25, 2020 Presented by The Earthrise Institute # 17 Authored by Alan Hale This week in history APRIL 19 20 21 22 23 24 25 APRIL 20, 1910: Comet 1P/Halley passes through perihelion at a heliocentric distance of 0.587 AU. Halley’s 1910 return, which is described in a previous “Special Topics” presentation, was quite favorable, with a close approach to Earth (0.15 AU) and the exhibiting of the longest cometary tail ever recorded. APRIL 20, 2025: NASA’s Lucy mission is scheduled to pass by the main belt asteroid (52246) Donaldjohanson. Lucy is discussed in a previous “Special Topics” presentation. APRIL 19 20 21 22 23 24 25 APRIL 21, 2024: Comet 12P/Pons-Brooks is predicted to pass through perihelion at a heliocentric distance of 0.781 AU. This comet, with a discussion of its viewing prospects for 2024, is a previous “Comet of the Week.” APRIL 19 20 21 22 23 24 25 APRIL 22, 2020: The annual Lyrid meteor shower should be at its peak. Normally this shower is fairly weak, with a peak rate of not much more than 10 meteors per hour, but has been known to exhibit significantly stronger activity on occasion. The moon is at its “new” phase on April 23 this year and thus the viewing circumstances are very good. COVER IMAGE CREDIT: Front and back cover: This artist’s conception shows how families of asteroids are created. Over the history of our solar system, catastrophic collisions between asteroids located in the belt between Mars and Jupiter have formed families of objects on similar orbits around the sun. -
Comets in UV
Comets in UV B. Shustov1 • M.Sachkov1 • Ana I. G´omez de Castro 2 • Juan C. Vallejo2 • E.Kanev1 • V.Dorofeeva3,1 Abstract Comets are important “eyewitnesses” of So- etary systems too. Comets are very interesting objects lar System formation and evolution. Important tests to in themselves. A wide variety of physical and chemical determine the chemical composition and to study the processes taking place in cometary coma make of them physical processes in cometary nuclei and coma need excellent space laboratories that help us understand- data in the UV range of the electromagnetic spectrum. ing many phenomena not only in space but also on the Comprehensive and complete studies require for ad- Earth. ditional ground-based observations and in-situ exper- We can learn about the origin and early stages of the iments. We briefly review observations of comets in evolution of the Solar System analogues, by watching the ultraviolet (UV) and discuss the prospects of UV circumstellar protoplanetary disks and planets around observations of comets and exocomets with space-born other stars. As to the Solar System itself comets are instruments. A special refer is made to the World Space considered to be the major “witnesses” of its forma- Observatory-Ultraviolet (WSO-UV) project. tion and early evolution. The chemical composition of cometary cores is believed to basically represent the Keywords comets: general, ultraviolet: general, ul- composition of the protoplanetary cloud from which traviolet: planetary systems the Solar System was formed approximately 4.5 billion years ago, i.e. over all this time the chemical composi- 1 Introduction tion of cores of comets (at least of the long period ones) has not undergone any significant changes. -
Comets in Full Sky $\Mathsf{L {\Alpha}}$ Maps of the SWAN Instrument
A&A 368, 292–297 (2001) Astronomy DOI: 10.1051/0004-6361:20000545 & c ESO 2001 Astrophysics CometsinfullskyLα maps of the SWAN instrument I. Survey from 1996 to 1998 J. T. T. M¨akinen1, J.-L. Bertaux2,T.I.Pulkkinen1,W.Schmidt1,E.Kyr¨ol¨a1, T. Summanen1, E. Qu´emerais2, and R. Lallement2 1 Finnish Meteorological Institute, Geophysics Research, PO Box 503, 00101 Helsinki, Finland 2 Service d’A´eronomie, BP 3, 91371 Verri`eres-le-Buisson, France Received 29 September 2000 / Accepted 8 December 2000 Abstract. The SWAN instrument onboard the SOHO spacecraft is a Lyman α scanning photometer cabable of mapping the whole sky with 1◦ resolution. Since January 1996 the instrument has produced on average three full sky maps a week with the principal scientific objective of observing the distribution of heliospheric neutral hydrogen. In addition, these systematic observations are a valuable source for studying comets brighter than a visual magnitude of 7–11, the observing limit depending on the abundance ratios of produced radicals and the location of the comet relative to the galactic plane. When the data before the temporary loss of control of SOHO at the end of June 1998 were processed, altogether 18 comets were positively identified, of which one is a new discovery and another 5 can be detected on SWAN images before their actual discovery date. This demonstrates the feasibility of SWAN as an instrument for cometary surveys. The observations are used to estimate the water production rates of the detected comets near their perihelion passages. Key words. data analysis – surveys – comets – ultraviolet: solar system 1. -
Fragmentation Hierarchy of Bright Sungrazing Comets and the Birth and Orbital Evolution of the Kreutz System
The Astrophysical Journal, 607:620–639, 2004 May 20 # 2004. The American Astronomical Society. All rights reserved. Printed in U.S.A. FRAGMENTATION HIERARCHY OF BRIGHT SUNGRAZING COMETS AND THE BIRTH AND ORBITAL EVOLUTION OF THE KREUTZ SYSTEM. I. TWO-SUPERFRAGMENT MODEL Zdenek Sekanina and Paul W. Chodas Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109; [email protected], [email protected] Received 2004 January 7; accepted 2004 February 6 ABSTRACT A back-and-forth orbit integration technique, developed for our previous investigation of the splitting of the parent of the sungrazers C/1882 R1 and C/1965 S1, is now applied in an effort to understand the history and orbital evolution of the Kreutz sungrazer system, starting with the birth of two subgroups, which show prom- inently among the bright members and whose inception dates back to the progenitor’s breakup into two superfragments. The integration technique is used to reproduce the motion of comet C/1843 D1—the second brightest sungrazer known and presumably the most massive surviving piece of superfragment I—from the motion of C/1882 R1—the brightest sungrazer on record and arguably the most massive surviving piece of superfragment II. Running the orbit of C/1882 R1 back to a.d. 326, the progenitor comet is found to have split at a heliocentric distance of 50 AU and nearly 30 yr before perihelion. The superfragments acquired separation velocities of 8msÀ1 in opposite directions. Using the same technique, we show next that (1) the motions of two additional sungrazers, C/1880 C1 and C/1887 B1, are matched extremely well if these objects shared a common parent with C/1843 D1, and (2) C/1963 R1 (Pereyra), the second brightest subgroup I member on record, is more closely related to subgroup II objects (such as C/1882 R1 and C/1965 S1) than to C/1843 D1. -
Comet ISON! (Comet of the Century?)
1 Mr. Justin J McCollum (BS, MS Physics) Lab Physics Coordinator Dept. of Physics Lamar University 2 Table of Contents ISON network………………..….………………….…...3 – 6 C/2012 S1 Discoverers………….…...……….…...…7 – 10 CoLiTech System…………………….……….….………...11 Discovery & Prediscovery……………….…….………...12 Early Orbital Analysis…………………….……….…….…13 Speculations of Comet ISON…………..…………14 - 15 Oort or Oort – Opik Cloud………….……........16 – 17 Origin of Comet ISON……….………………….……….18 Sungrazer Comets…………………………………….19 - 20 Evolution of Comet ISON………………………………21 Facts about Comet ISON…………………....…..22 – 23 ISON a Pristine Comet?...............................24 – 25 Photometry & Current Brightness……………..26 – 27 Nature and State of the Coma…………………..28 – 30 Central Nucleus of Comet ISON………………31 – 32 Nucleus to the Tail……………………………….…..……33 Nature & State of the Tail…………………………34 – 35 Future & Expectations………………………….....36 – 39 Getting to know more about Comets!...........40 – 46 After Perihelion Passage!..............................47 – 49 Catching the Comet in December!…………….50 – 53 ISON in the Daytime…….…………………………….…54 NASA Involvement!.............................................55 C/2012 S1 Orbital Structure………………..…………..56 Ephemeris Terminology………………………………...57 Data Spreadsheet Introduction………………………..58 Data Table Spreadsheets…………………………..59 - 60 Comet ISON Updates………………………………61 - 62 Knowing where & how to find ISON……...…63 – 64 Current ISON Observing Campaign………….65 – 66 Comet ISON photo contest…………………………….67 End Page……………………………………………………...68 3 Imperial Academy of -
Kometen Im Visier Rosetta Eröffnet Eine Neue Ära Der Kometen-Astronomie
interstellarum THEMA | 1/2014 fokussiert Titelbild: Während ISON kläglich an der Sonne scheiterte, stieß C/2013 R1 Lovejoy in die Lücke. Das Foto zeigt ihn am 12.12.2013. CCD-Aufnahme, 5:14 MEZ, 8"-Astrograph bei 560mm, FLI PL 16070, 5min (je LRGB). Gerald Rhemann INTERAKTIV Auf Twitter informieren wir Sie tagesaktuell über astronomische Ereignisse und geben Updates. Folgen Sie @interstellarum! Kurzlink: oclm.de/twt BUCHTIPP Liebe Leserinnen, liebe Leser, Atlas der Großen Kometen eigentlich war alles ganz anders geplant: Dieses Themenheft sollte eine imposante Rückschau auf den Jahrhundert-Auftritt des Kometen ISON werden; mit Ihren Fotos, viel Hintergrundinformation und Begeisterung. Leider ist bekanntlich alles ganz anders gekommen. Komet ISON kommt in diesem Heft nun nur noch am Rande vor: Daniel Fischer fasst die bisherigen Kenntnisse über das Scheitern in seiner Analyse zusammen (S. 24). Stefan Binnewies und Rainer Sparenberg berichten von der vergeblichen Suche nach ISON auf La Palma (S. 64). Dennoch: Das Kometenjahr 2013 war besser als sein Ruf. Das zeigt der ausführliche Rückblick von Burkhard Leitner mit beeindruckenden Fotos der Kometen-Fotoexperten Gerald Rhemann und Waldemar Skorupa (S. 30). Ronald Stoyan, Oculum-Verlag, Im Fokus dieser Ausgabe stehen die spannenden Ereignisse, die im zweiten Halb- ISBN: 978-3-938469-70-5, jahr 2014 folgen werden: Mit Rosetta wird erstmals eine Raumsonde in den Orbit um 49,90€. einen Kometen einschwenken, und sogar ein Landemodul auf diesem absetzen. Was sich Forscher davon erhoffen, schildert Daniel Fischer in seiner Titelgeschichte (S. 8). Kometen- Kurzlink: oclm.de/03ac Astronom Harald Krüger gibt in seinem Artikel einen umfassenden Überblick über das heutige Wissen zu Schweifsternen vor Rosetta (S.