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Asteroid Shape and Spin Statistics from Convex Models J
Asteroid shape and spin statistics from convex models J. Torppa, V.-P. Hentunen, P. Pääkkönen, P. Kehusmaa, K. Muinonen To cite this version: J. Torppa, V.-P. Hentunen, P. Pääkkönen, P. Kehusmaa, K. Muinonen. Asteroid shape and spin statistics from convex models. Icarus, Elsevier, 2008, 198 (1), pp.91. 10.1016/j.icarus.2008.07.014. hal-00499092 HAL Id: hal-00499092 https://hal.archives-ouvertes.fr/hal-00499092 Submitted on 9 Jul 2010 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. Accepted Manuscript Asteroid shape and spin statistics from convex models J. Torppa, V.-P. Hentunen, P. Pääkkönen, P. Kehusmaa, K. Muinonen PII: S0019-1035(08)00283-2 DOI: 10.1016/j.icarus.2008.07.014 Reference: YICAR 8734 To appear in: Icarus Received date: 18 September 2007 Revised date: 3 July 2008 Accepted date: 7 July 2008 Please cite this article as: J. Torppa, V.-P. Hentunen, P. Pääkkönen, P. Kehusmaa, K. Muinonen, Asteroid shape and spin statistics from convex models, Icarus (2008), doi: 10.1016/j.icarus.2008.07.014 This is a PDF file of an unedited manuscript that has been accepted for publication. -
Occultation Newsletter Volume 8, Number 4
Volume 12, Number 1 January 2005 $5.00 North Am./$6.25 Other International Occultation Timing Association, Inc. (IOTA) In this Issue Article Page The Largest Members Of Our Solar System – 2005 . 4 Resources Page What to Send to Whom . 3 Membership and Subscription Information . 3 IOTA Publications. 3 The Offices and Officers of IOTA . .11 IOTA European Section (IOTA/ES) . .11 IOTA on the World Wide Web. Back Cover ON THE COVER: Steve Preston posted a prediction for the occultation of a 10.8-magnitude star in Orion, about 3° from Betelgeuse, by the asteroid (238) Hypatia, which had an expected diameter of 148 km. The predicted path passed over the San Francisco Bay area, and that turned out to be quite accurate, with only a small shift towards the north, enough to leave Richard Nolthenius, observing visually from the coast northwest of Santa Cruz, to have a miss. But farther north, three other observers video recorded the occultation from their homes, and they were fortuitously located to define three well- spaced chords across the asteroid to accurately measure its shape and location relative to the star, as shown in the figure. The dashed lines show the axes of the fitted ellipse, produced by Dave Herald’s WinOccult program. This demonstrates the good results that can be obtained by a few dedicated observers with a relatively faint star; a bright star and/or many observers are not always necessary to obtain solid useful observations. – David Dunham Publication Date for this issue: July 2005 Please note: The date shown on the cover is for subscription purposes only and does not reflect the actual publication date. -
Asteroid Family Identification 613
Bendjoya and Zappalà: Asteroid Family Identification 613 Asteroid Family Identification Ph. Bendjoya University of Nice V. Zappalà Astronomical Observatory of Torino Asteroid families have long been known to exist, although only recently has the availability of new reliable statistical techniques made it possible to identify a number of very “robust” groupings. These results have laid the foundation for modern physical studies of families, thought to be the direct result of energetic collisional events. A short summary of the current state of affairs in the field of family identification is given, including a list of the most reliable families currently known. Some likely future developments are also discussed. 1. INTRODUCTION calibrate new identification methods. According to the origi- nal papers published in the literature, Brouwer (1951) used The term “asteroid families” is historically linked to the a fairly subjective criterion to subdivide the Flora family name of the Japanese researcher Kiyotsugu Hirayama, who delineated by Hirayama. Arnold (1969) assumed that the was the first to use the concept of orbital proper elements to asteroids are dispersed in the proper-element space in a identify groupings of asteroids characterized by nearly iden- Poisson distribution. Lindblad and Southworth (1971) cali- tical orbits (Hirayama, 1918, 1928, 1933). In interpreting brated their method in such a way as to find good agree- these results, Hirayama made the hypothesis that such a ment with Brouwer’s results. Carusi and Massaro (1978) proximity could not be due to chance and proposed a com- adjusted their method in order to again find the classical mon origin for the members of these groupings. -
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1,. ,-- ,-- ~XECKDING PAGE BLANK WT FIL,,q DYNAMICAL EVIDENCE REGARDING THE RELATIONSHIP BETWEEN ASTEROIDS AND METEORITES GEORGE W. WETHERILL Department of Temcltricrl kgnetism ~amregie~mtittition of Washington Washington, D. C. 20025 Meteorites are fragments of small solar system bodies (comets, asteroids and Apollo objects). Therefore they may be expected to provide valuable information regarding these bodies. How- ever, the identification of particular classes of meteorites with particular small bodies or classes of small bodies is at present uncertain. It is very unlikely that any significant quantity of meteoritic material is obtained from typical ac- tive comets. Relatively we1 1-studied dynamical mechanisms exist for transferring material into the vicinity of the Earth from the inner edge of the asteroid belt on an 210~-~year time scale. It seems likely that most iron meteorites are obtained in this way, and a significant yield of complementary differec- tiated meteoritic silicate material may be expected to accom- pany these differentiated iron meteorites. Insofar as data exist, photometric measurements support an association between Apollo objects and chondri tic meteorites. Because Apol lo ob- jects are in orbits which come close to the Earth, and also must be fragmented as they traverse the asteroid belt near aphel ion, there also must be a component of the meteorite flux derived from Apollo objects. Dynamical arguments favor the hypothesis that most Apollo objects are devolatilized comet resiaues. However, plausible dynamical , petrographic, and cosmogonical reasons are known which argue against the simple conclusion of this syllogism, uiz., that chondri tes are of cometary origin. Suggestions are given for future theoretical , observational, experimental investigations directed toward improving our understanding of this puzzling situation. -
New Double Stars from Asteroidal Occultations, 1971 - 2008
Vol. 6 No. 1 January 1, 2010 Journal of Double Star Observations Page 88 New Double Stars from Asteroidal Occultations, 1971 - 2008 Dave Herald, Canberra, Australia International Occultation Timing Association (IOTA) Robert Boyle, Carlisle, Pennsylvania, USA Dickinson College David Dunham, Greenbelt, Maryland, USA; Toshio Hirose, Tokyo, Japan; Paul Maley, Houston, Texas, USA; Bradley Timerson, Newark, New York, USA International Occultation Timing Association (IOTA) Tim Farris, Gallatin, Tennessee, USA Volunteer State Community College Eric Frappa and Jean Lecacheux, Paris, France Observatoire de Paris Tsutomu Hayamizu, Kagoshima, Japan Sendai Space Hall Marek Kozubal, Brookline, Massachusetts, USA Clay Center Richard Nolthenius, Aptos, California, USA Cabrillo College and IOTA Lewis C. Roberts, Jr., Pasadena, California, USA California Institute of Technology/Jet Propulsion Laboratory David Tholen, Honolulu, Hawaii, USA University of Hawaii E-mail: [email protected] Abstract: Observations of occultations by asteroids and planetary moons can detect double stars with separations in the range of about 0.3” to 0.001”. This paper lists all double stars detected in asteroidal occultations up to the end of 2008. It also provides a general explanation of the observational method and analysis. The incidence of double stars with a separation in the range 0.001” to 0.1” with a magnitude difference less than 2 is estimated to be about 1%. Vol. 6 No. 1 January 1, 2010 Journal of Double Star Observations Page 89 New Double Stars from Asteroidal Occultations, 1971 - 2008 tions. More detail about the method of analysis is set Introduction out in the Appendix. Asteroids and planetary moons will naturally oc- cult many stars as they move through the sky. -
Zákryt Jasné Hvězdy Saturnem
Zákrytová a astrometrická sekce ČAS leden 2006 (1) Zajímavosti: NENECHTE SI UJÍT Zákryt jasné hv ězdy Saturnem 25. ledna 2006 ve čer mimo jiné i Evropu čeká velice zajímavá ř ě Č podívaná. Planeta Saturn okrášlená prstencem p řejde p řes relativn ě Situace, jak vypadá p i pohledu z hv zdy. asy udávané v malé vložené ě ě č jasnou hv ězdu a ze Zem ě budeme mít možnost sledovat nejen zákryt tabulce jsou platné pro Mainz (N mecko). Pro jiná místa v Evrop jsou asy v tabulce za článkem. stálice vlastní planetou, ale i její poblikávání za jednotlivými prstenci. Velice zajímavé bude jist ě pokusit se celý úkaz nahrát speciálními videokamerami v ohnisku dlouhofokálních teleobjektiv ů či dalekohled ů. Zajímavá a nevšední podívaná však čeká jist ě i na ty, kdo se na úkaz budou chtít pouze vizuáln ě podívat. Lednový zákryt hv ězdy Saturnem je jist ě zajímavou údálostí, ale nemá p říliš velkou publicitu. Úkaz bude viditelný z Evropy, Afriky a Asie. P řičemž z jižní Afriky bude možno sledovat pouze zákryty hv ězdy prstenci a zákryt vlastní planetou tuto oblast již mine. U nás, ve st řední Evrop ě, by úkaz m ěl za čít v 18:45 UT, kdy se hv ězda dostane k vn ějšímu okraji soustavy prstenc ů. V tom čase bude planeta již dostate čně vysoko nad východním obzorem (h=26°; A=92°). Zákryt Pr ůchod hv ězdy oblastí systému satelit ů planety Saturn p ři pohledu ze Země kotou čkem planety pak nastane v intervalu 20:08 UT (D – vstup) až 20:49 (R – (geocentrický pohled). -
1 Spectral Evidence for Amorphous Silicates in Least-Processed
Spectral Evidence for Amorphous Silicates in Least-processed CO Meteorites and Their Parent Bodies Authors: Margaret M. McAdam1, 2, Jessica M. Sunshine1, Kieren T. Howard3, 4, Conel M. O’D Alexander5, Timothy J. McCoy6, Schelte J. Bus7 1 University of Maryland, Department of Astronomy, College Park, MD 20740. [email protected] 2 Northern Arizona University, Department of Physics and Astronomy, Flagstaff AZ 86011. [email protected] 3American Museum of Natural History 4 Kingsborough Community College 5 Department of Terrestrial Magnetism, Carnegie Institution 6 National Museum of Natural History, Smithsonian Institution. 7 University of Hawaii, Institute for Astronomy Abstract: Least-processed carbonaceous chondrites (carbonaceous chondrites that have experienced minimal aqueous alteration and thermal metamorphism) are characterized by their predominately amorphous iron-rich silicate interchondrule matrices and chondrule rims. This material is highly susceptible to destruction by the parent body processes of thermal metamorphism or aqueous alteration. The presence of abundant amorphous material in a meteorite indicates that the parent body, or at least a region of the parent body, experienced minimal processing since the time of accretion. The CO chemical group of carbonaceous chondrites has a significant number of these least-processed samples. We present visible/near- infrared and mid-infrared spectra of eight least-processed CO meteorites (petrologic type 3.0- 3.1). In the visible/near-infrared, these COs are characterized by a broad weak feature that was first observed by Cloutis et al. (2012) to be at 1.3-µm and attributed to iron-rich amorphous silicate matrix materials. This feature is observed to be centered at 1.4-µm for terrestrially unweathered, least-processed CO meteorites. -
IRTF Spectra for 17 Asteroids from the C and X Complexes: a Discussion of Continuum Slopes and Their Relationships to C Chondrites and Phyllosilicates ⇑ Daniel R
Icarus 212 (2011) 682–696 Contents lists available at ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus IRTF spectra for 17 asteroids from the C and X complexes: A discussion of continuum slopes and their relationships to C chondrites and phyllosilicates ⇑ Daniel R. Ostrowski a, Claud H.S. Lacy a,b, Katherine M. Gietzen a, Derek W.G. Sears a,c, a Arkansas Center for Space and Planetary Sciences, University of Arkansas, Fayetteville, AR 72701, United States b Department of Physics, University of Arkansas, Fayetteville, AR 72701, United States c Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, United States article info abstract Article history: In order to gain further insight into their surface compositions and relationships with meteorites, we Received 23 April 2009 have obtained spectra for 17 C and X complex asteroids using NASA’s Infrared Telescope Facility and SpeX Revised 20 January 2011 infrared spectrometer. We augment these spectra with data in the visible region taken from the on-line Accepted 25 January 2011 databases. Only one of the 17 asteroids showed the three features usually associated with water, the UV Available online 1 February 2011 slope, a 0.7 lm feature and a 3 lm feature, while five show no evidence for water and 11 had one or two of these features. According to DeMeo et al. (2009), whose asteroid classification scheme we use here, 88% Keywords: of the variance in asteroid spectra is explained by continuum slope so that asteroids can also be charac- Asteroids, composition terized by the slopes of their continua. -
Multiple Asteroid Systems: Dimensions and Thermal Properties from Spitzer Space Telescope and Ground-Based Observations Q ⇑ F
Icarus 221 (2012) 1130–1161 Contents lists available at SciVerse ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus Multiple asteroid systems: Dimensions and thermal properties from Spitzer Space Telescope and ground-based observations q ⇑ F. Marchis a,g, , J.E. Enriquez a, J.P. Emery b, M. Mueller c, M. Baek a, J. Pollock d, M. Assafin e, R. Vieira Martins f, J. Berthier g, F. Vachier g, D.P. Cruikshank h, L.F. Lim i, D.E. Reichart j, K.M. Ivarsen j, J.B. Haislip j, A.P. LaCluyze j a Carl Sagan Center, SETI Institute, 189 Bernardo Ave., Mountain View, CA 94043, USA b Earth and Planetary Sciences, University of Tennessee, 306 Earth and Planetary Sciences Building, Knoxville, TN 37996-1410, USA c SRON, Netherlands Institute for Space Research, Low Energy Astrophysics, Postbus 800, 9700 AV Groningen, Netherlands d Appalachian State University, Department of Physics and Astronomy, 231 CAP Building, Boone, NC 28608, USA e Observatorio do Valongo, UFRJ, Ladeira Pedro Antonio 43, Rio de Janeiro, Brazil f Observatório Nacional, MCT, R. General José Cristino 77, CEP 20921-400 Rio de Janeiro, RJ, Brazil g Institut de mécanique céleste et de calcul des éphémérides, Observatoire de Paris, Avenue Denfert-Rochereau, 75014 Paris, France h NASA, Ames Research Center, Mail Stop 245-6, Moffett Field, CA 94035-1000, USA i NASA, Goddard Space Flight Center, Greenbelt, MD 20771, USA j Physics and Astronomy Department, University of North Carolina, Chapel Hill, NC 27514, USA article info abstract Article history: We collected mid-IR spectra from 5.2 to 38 lm using the Spitzer Space Telescope Infrared Spectrograph Available online 2 October 2012 of 28 asteroids representative of all established types of binary groups. -
ABSTRACT Title of Dissertation: WATER in the EARLY SOLAR
ABSTRACT Title of Dissertation: WATER IN THE EARLY SOLAR SYSTEM: INFRARED STUDIES OF AQUEOUSLY ALTERED AND MINIMALLY PROCESSED ASTEROIDS Margaret M. McAdam, Doctor of Philosophy, 2017. Dissertation directed by: Professor Jessica M. Sunshine, Department of Astronomy This thesis investigates connections between low albedo asteroids and carbonaceous chondrite meteorites using spectroscopy. Meteorites and asteroids preserve information about the early solar system including accretion processes and parent body processes active on asteroids at these early times. One process of interest is aqueous alteration. This is the chemical reaction between coaccreted water and silicates producing hydrated minerals. Some carbonaceous chondrites have experienced extensive interactions with water through this process. Since these meteorites and their parent bodies formed close to the beginning of the Solar System, these asteroids and meteorites may provide clues to the distribution, abundance and timing of water in the Solar nebula at these times. Chapter 2 of this thesis investigates the relationships between extensively aqueously altered meteorites and their visible, near and mid-infrared spectral features in a coordinated spectral-mineralogical study. Aqueous alteration is a parent body process where initially accreted anhydrous minerals are converted into hydrated minerals in the presence of coaccreted water. Using samples of meteorites with known bulk properties, it is possible to directly connect changes in mineralogy caused by aqueous alteration with spectral features. Spectral features in the mid-infrared are found to change continuously with increasing amount of hydrated minerals or degree of alteration. Building on this result, the degrees of alteration of asteroids are estimated in a survey of new asteroid data obtained from SOFIA and IRTF as well as archived the Spitzer Space Telescope data. -
Taxonomic Classification of Asteroids Based on MOVIS Near-Infrared Colors
A&A 617, A12 (2018) https://doi.org/10.1051/0004-6361/201833023 Astronomy & © ESO 2018 Astrophysics Taxonomic classification of asteroids based on MOVIS near-infrared colors? M. Popescu1,2,3, J. Licandro1,2, J. M. Carvano4, R. Stoicescu3, J. de León1,2, D. Morate1,2, I. L. Boaca˘3, and C. P. Cristescu5 1 Instituto de Astrofísica de Canarias (IAC), C/Vía Láctea s/n, 38205 La Laguna, Tenerife, Spain 2 Departamento de Astrofísica, Universidad de La Laguna, 38206 La Laguna, Tenerife, Spain e-mail: [email protected] 3 Astronomical Institute of the Romanian Academy, 5 Cu¸titulde Argint, 040557 Bucharest, Romania 4 Observatório Nacional, rua Gal. José Cristino 77, São Cristóvão, 20921-400 Rio de Janeiro, Brazil 5 Department of Physics, University Politehnica of Bucharest, Bucure¸sti 060042, Romania Received 14 March 2018 / Accepted 14 June 2018 ABSTRACT Context. The MOVIS catalog contains the largest set of near-infrared (NIR) colors for solar system objects. These data were obtained from the observations performed by VISTA-VHS survey using the Y, J, H, and Ks filters. The taxonomic classification of objects in this catalog allows us to obtain large-scale distributions for the asteroidal population, to study faint objects, and to select targets for detailed spectral investigations. Aims. We aim to provide a taxonomic classification for asteroids observed by VISTA-VHS survey. We derive a method for assigning a compositional type to an object based on its (Y − J), (J − Ks), and (H − Ks) colors. Methods. We present a taxonomic classification for 18 265 asteroids from the MOVIS catalog, using a probabilistic method and the k-nearest neighbors algorithm. -
Binary Asteroid Lightcurves
BINARY ASTEROID LIGHTCURVES Asteroid Type Per1 Amp1 Per2 Amp2 Perorb Ds/Dp a/Dp Reference 22 Kalliope B 4.1483 0.53 B a Descamps, 08 B a 86.2896 Marchis, 08 B a 4.148 86.16 Marchis, 11w 41∗ Daphne B 5.988 0.45 B s 26.4 Conrad, 08 B s 38. Conrad, 08 B s 5.987981 27.289 2.46 Carry, 18 45 Eugenia M 5.699 0.30 B a 113. Merline, 99 B a Marchis, 06 M a Marchis, 07 M a Marchis, 08 B a 5.6991 114.38 Marchis, 11w 87 Sylvia M 5.184 0.50 M a 5.184 87.5904 Marchis, 05 M a 5.1836 87.59 Marchis, 11w 90∗ Antiope B 16.509 0.88 B f 16. Merline, 00 B f 16.509 0.73 16.509 0.73 16.509 Descamps, 05 B f 16.5045 0.86 16.5045 0.86 16.5045 Behrend, 07w B f 16.505046 16.505046 Bartczak, 14 93 Minerva M 5.982 0.20 M a 5.982 0.20 57.79 Marchis, 11 107∗ Camilla M 4.844 0.53 B a Marchis, 08 B a 4.8439 89.04 Marchis, 11w M a 1.550 Marsset, 16 M s 89.096 4.91 Pajuelo, 18 113 Amalthea B? 9.950 0.22 ? u Maley, 17 121 Hermione B 5.55128 0.62 B a Merline, 02 B a Marchis, 04 B a Marchis, 05 B a 5.55 61.97 Marchis, 11w 130 Elektra M 5.225 0.58 B a 5.22 126.2 Marchis, 08 M a Yang, 14 216 Kleopatra M 5.385 1.22 M a 5.38 Marchis, 08 243 Ida B 4.634 0.86 B a Belton, 94 279 Thule B? 23.896 0.10 B s 7.44 0.08 72.2 Sato, 15 283 Emma B 6.896 0.53 B a Merline, 03 B a 6.89 80.48 Marchis, 08 324 Bamberga B? 29.43 0.12 B s 29.458 0.06 71.0 Sato, 15 379 Huenna B 14.141 0.12 B a Margot, 03 B a 4.022 2102.