Formation and Evolution of Binary Asteroids
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Copyrighted Material
Index Abulfeda crater chain (Moon), 97 Aphrodite Terra (Venus), 142, 143, 144, 145, 146 Acheron Fossae (Mars), 165 Apohele asteroids, 353–354 Achilles asteroids, 351 Apollinaris Patera (Mars), 168 achondrite meteorites, 360 Apollo asteroids, 346, 353, 354, 361, 371 Acidalia Planitia (Mars), 164 Apollo program, 86, 96, 97, 101, 102, 108–109, 110, 361 Adams, John Couch, 298 Apollo 8, 96 Adonis, 371 Apollo 11, 94, 110 Adrastea, 238, 241 Apollo 12, 96, 110 Aegaeon, 263 Apollo 14, 93, 110 Africa, 63, 73, 143 Apollo 15, 100, 103, 104, 110 Akatsuki spacecraft (see Venus Climate Orbiter) Apollo 16, 59, 96, 102, 103, 110 Akna Montes (Venus), 142 Apollo 17, 95, 99, 100, 102, 103, 110 Alabama, 62 Apollodorus crater (Mercury), 127 Alba Patera (Mars), 167 Apollo Lunar Surface Experiments Package (ALSEP), 110 Aldrin, Edwin (Buzz), 94 Apophis, 354, 355 Alexandria, 69 Appalachian mountains (Earth), 74, 270 Alfvén, Hannes, 35 Aqua, 56 Alfvén waves, 35–36, 43, 49 Arabia Terra (Mars), 177, 191, 200 Algeria, 358 arachnoids (see Venus) ALH 84001, 201, 204–205 Archimedes crater (Moon), 93, 106 Allan Hills, 109, 201 Arctic, 62, 67, 84, 186, 229 Allende meteorite, 359, 360 Arden Corona (Miranda), 291 Allen Telescope Array, 409 Arecibo Observatory, 114, 144, 341, 379, 380, 408, 409 Alpha Regio (Venus), 144, 148, 149 Ares Vallis (Mars), 179, 180, 199 Alphonsus crater (Moon), 99, 102 Argentina, 408 Alps (Moon), 93 Argyre Basin (Mars), 161, 162, 163, 166, 186 Amalthea, 236–237, 238, 239, 241 Ariadaeus Rille (Moon), 100, 102 Amazonis Planitia (Mars), 161 COPYRIGHTED -
Determination of Binary Asteroid Orbits with a Genetic-Based Algorithm Frédéric Vachier, Jérôme Berthier, Franck Marchis
Determination of binary asteroid orbits with a genetic-based algorithm Frédéric Vachier, Jérôme Berthier, Franck Marchis To cite this version: Frédéric Vachier, Jérôme Berthier, Franck Marchis. Determination of binary asteroid orbits with a genetic-based algorithm. Astronomy and Astrophysics - A&A, EDP Sciences, 2012, 543, pp.A68. 10.1051/0004-6361/201118408. hal-00719660 HAL Id: hal-00719660 https://hal.sorbonne-universite.fr/hal-00719660 Submitted on 20 Jul 2012 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. A&A 543, A68 (2012) Astronomy DOI: 10.1051/0004-6361/201118408 & c ESO 2012 Astrophysics Determination of binary asteroid orbits with a genetic-based algorithm F. Vachier1, J. Berthier1, and F. Marchis2,1 1 Institut de mécanique céleste et de calcul des éphémérides, Observatoire de Paris, Avenue Denfert-Rochereau, 75014 Paris, France e-mail: [email protected] 2 Carl Sagan Center, SETI Institute, 189 Bernardo Avenue, Mountain View CA 94043, USA Received 5 November 2011 / Accepted 28 April 2012 ABSTRACT Aims. Over the past decade, discoveries of multiple and binary asteroid systems have played a significant role in our general under- standing of small solar system bodies. -
Multiple Asteroid Systems: Dimensions and Thermal Properties from Spitzer Space Telescope and Ground-Based Observations*
Multiple Asteroid Systems: Dimensions and Thermal Properties from Spitzer Space Telescope and Ground-Based Observations* F. Marchisa,g, J.E. Enriqueza, J. P. Emeryb, M. Muellerc, M. Baeka, J. Pollockd, M. Assafine, R. Vieira Martinsf, J. Berthierg, F. Vachierg, D. P. Cruikshankh, L. Limi, D. Reichartj, K. Ivarsenj, J. Haislipj, A. LaCluyzej 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 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, United States j. Physics and Astronomy Department, University of North Carolina, Chapel Hill, NC 27514, U.S.A * Based in part on observations collected at the European Southern Observatory, Chile Programs Numbers 70.C-0543 and ID 72.C-0753 Corresponding author: Franck Marchis Carl Sagan Center SETI Institute 189 Bernardo Ave. Mountain View CA 94043 USA [email protected] Abstract: We collected mid-IR spectra from 5.2 to 38 µm using the Spitzer Space Telescope Infrared Spectrograph of 28 asteroids representative of all established types of binary groups. -
(101955) Bennu from OSIRIS-Rex Imaging and Thermal Analysis
ARTICLES https://doi.org/10.1038/s41550-019-0731-1 Properties of rubble-pile asteroid (101955) Bennu from OSIRIS-REx imaging and thermal analysis D. N. DellaGiustina 1,26*, J. P. Emery 2,26*, D. R. Golish1, B. Rozitis3, C. A. Bennett1, K. N. Burke 1, R.-L. Ballouz 1, K. J. Becker 1, P. R. Christensen4, C. Y. Drouet d’Aubigny1, V. E. Hamilton 5, D. C. Reuter6, B. Rizk 1, A. A. Simon6, E. Asphaug1, J. L. Bandfield 7, O. S. Barnouin 8, M. A. Barucci 9, E. B. Bierhaus10, R. P. Binzel11, W. F. Bottke5, N. E. Bowles12, H. Campins13, B. C. Clark7, B. E. Clark14, H. C. Connolly Jr. 15, M. G. Daly 16, J. de Leon 17, M. Delbo’18, J. D. P. Deshapriya9, C. M. Elder19, S. Fornasier9, C. W. Hergenrother1, E. S. Howell1, E. R. Jawin20, H. H. Kaplan5, T. R. Kareta 1, L. Le Corre 21, J.-Y. Li21, J. Licandro17, L. F. Lim6, P. Michel 18, J. Molaro21, M. C. Nolan 1, M. Pajola 22, M. Popescu 17, J. L. Rizos Garcia 17, A. Ryan18, S. R. Schwartz 1, N. Shultz1, M. A. Siegler21, P. H. Smith1, E. Tatsumi23, C. A. Thomas24, K. J. Walsh 5, C. W. V. Wolner1, X.-D. Zou21, D. S. Lauretta 1 and The OSIRIS-REx Team25 Establishing the abundance and physical properties of regolith and boulders on asteroids is crucial for understanding the for- mation and degradation mechanisms at work on their surfaces. Using images and thermal data from NASA’s Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) spacecraft, we show that asteroid (101955) Bennu’s surface is globally rough, dense with boulders, and low in albedo. -
2017 Fall Event Brochure
RING RD LOCATIONS ELM ST 1 MAIN LIBRARY LIBRARIES IN RED 1510 E UNIVERSITY BLVD PARKING GARAGES IN BLUE WARREN AVE WARREN 520.621.6442 ARIZONA HEALTH LIBRARY.ARIZONA.EDU FOR FULL PARKING MAP AND FEE INFORMATION SCIENCES CENTER PARKING.ARIZONA.EDU, 520.626.7275 CAMPBELL AVE CAMPBELL 2 SCIENCE-ENGINEERING LIBRARY 744 N HIGHLAND AVE 520.621.6384 E DRACHMAN ST UAMC VINE AVE PATIENT & VISITOR GARAGE 3 FINE ARTS LIBRARY HIGHLAND AVE PARK AVE PARK HIGHLAND E MABEL ST 1017 N OLIVE RD GARAGE AVE CHERRY FRED FOX SCHOOL OF MUSIC MOUNTAIN AVE MOUNTAIN 2nd FLOOR, ROOM 233 E HELEN ST 520.621.7009 PARK AVE GARAGE 4 SPECIAL COLLECTIONS EUCLID AVE WARREN AVE WARREN 1510 E UNIVERSITY BLVD E SPEEDWAY BLVD E SPEEDWAY BLVD 520.621.6423 SPECCOLL.LIBRARY.ARIZONA.EDU ONE WAY E FIRST ST MUSIC TYNDALL AVE TYNDALL BLDG 5 HEALTH SCIENCES LIBRARY E FIRST ST 1501 N CAMPBELL AVE MOUNTAIN AVE MOUNTAIN CAMPBELL AVE CAMPBELL PALM DR PALM OLIVE RD SECOND ST 2nd FLOOR MAIN ONE WAY E SECOND ST GATE GARAGE 520.626.6125 GARAGE AHSL.ARIZONA.EDU E SECOND ST COVER IMAGE: CHERRY AVE CHERRY Detail, Portrait of Martin Luther, OLD MALL CLOSED TO TRAFFIC E UNIVERSITY BLVD by Lucas Cranach the Elder (1472-1553), MAIN E UNIVERSITY BLVD 1528 (Veste Coburg), oil on panel TYNDALL AVE GARAGE CHERRY AVE GARAGE E FOURTH ST E FOURTH ST CHERRY AVE CHERRY ENKE DR TYNDALL AVE TYNDALL PARK AVE PARK LOWELL CAMPBELL AVE CAMPBELL EUCLID AVE NAT’L CHAMPIONS DR CHAMPIONS NAT’L SIXTH ST HIGHLAND AVE E SIXTH ST GARAGE E SIXTH ST FALL 2017 SPECIAL COLLECTIONS SPECIAL EVENTS speccoll.library.arizona.edu Library Cats Tech Breakfast Contact: Kathy McCarthy | 520.626.8332 Saturday, October 28, 9–11 a.m., Science-Engineering Library [email protected] All alumni and friends are welcome at our Homecoming EXHIBIT | Opens August 7 celebration. -
Chapter 12 the Moon and Mercury: Comparing Airless Worlds The
11/4/2015 The Moon: The View from Earth From Earth, we always see the same side of the moon. Moon rotates around its axis in the same time that it takes to orbit Chapter 12 around Earth: The Moon and Mercury: Tidal coupling: Earth’s gravitation has Comparing Airless Worlds produced tidal bulges on the moon; Tidal forces have slowed rotation down to same period as orbital period Lunar Surface Features Highlands and Lowlands Two dramatically Sinuous rilles = different kinds of terrain: remains of ancient • Highlands: lava flows Mountainous terrain, scarred by craters May have been lava • Lowlands: ~ 3 km lower than highlands; smooth tubes which later surfaces: collapsed due to Maria (pl. of mare): meteorite bombardment. Basins flooded by Apollo 15 lava flows landing site The Highlands Impact Cratering Saturated with craters Impact craters on the moon can be seen easily even with small telescopes. Older craters partially … or flooded by Ejecta from the impact can be seen as obliterated by more lava flows bright rays originating from young recent impacts craters 1 11/4/2015 History of Impact Cratering Missions to the Moon Rate of impacts due to Major challenges: interplanetary Need to carry enough fuel for: bombardment decreased • in-flight corrections, rapidly after the formation of the solar system. • descent to surface, • re-launch from the surface, • return trip to Earth; Most craters seen on the need to carry enough food and other moon’s (and Mercury’s) life support for ~ 1 week for all surface were formed astronauts on board. Lunar module (LM) of within the first ~ ½ billion Solution: Apollo 12 on descent to the years. -
Space Weathering on Mercury
Advances in Space Research 33 (2004) 2152–2155 www.elsevier.com/locate/asr Space weathering on Mercury S. Sasaki *, E. Kurahashi Department of Earth and Planetary Science, The University of Tokyo, Tokyo 113 0033, Japan Received 16 January 2003; received in revised form 15 April 2003; accepted 16 April 2003 Abstract Space weathering is a process where formation of nanophase iron particles causes darkening of overall reflectance, spectral reddening, and weakening of absorption bands on atmosphereless bodies such as the moon and asteroids. Using pulse laser irra- diation, formation of nanophase iron particles by micrometeorite impact heating is simulated. Although Mercurian surface is poor in iron and rich in anorthite, microscopic process of nanophase iron particle formation can take place on Mercury. On the other hand, growth of nanophase iron particles through Ostwald ripening or repetitive dust impacts would moderate the weathering degree. Future MESSENGER and BepiColombo mission will unveil space weathering on Mercury through multispectral imaging observations. Ó 2003 COSPAR. Published by Elsevier Ltd. All rights reserved. 1. Introduction irradiation should change the optical properties of the uppermost regolith surface of atmosphereless bodies. Space weathering is a proposed process to explain Although Hapke et al. (1975) proposed that formation spectral mismatch between lunar soils and rocks, and of iron particles with sizes from a few to tens nanome- between asteroids (S-type) and ordinary chondrites. ters should be responsible for the optical property Most of lunar surface and asteroidal surface exhibit changes, impact-induced formation of glassy materials darkening of overall reflectance, spectral reddening had been considered as a primary cause for space (darkening of UV–Vis relative to IR), and weakening of weathering. -
Kaae, Leonard Kuuleinamoku, July 19, 2012 Leonard Kuuleinamoku Kaae, 84, of Honolulu, a Retired Hawaiian Tug & Barge Seaman and an Army Veteran, Died
Kaae, Leonard Kuuleinamoku, July 19, 2012 Leonard Kuuleinamoku Kaae, 84, of Honolulu, a retired Hawaiian Tug & Barge seaman and an Army veteran, died. He was born in Honolulu. He is survived by wife Ruth H. and sisters Ethel Hardley and Rose Giltner. Private services. [Honolulu Star-Advertiser 11 August 2012] Kaahanui, Agnes Lily Kahihiulaokalani, 77, of Honolulu, Hawaii, passed away June 14, 2012 at Kuakini Medical Center. Born July 10, 1934 in Honolulu, Hawaii. She was retired Maintenance Housekeeping Personel at Iolani Palace. She is survived by sons, Clifford Kalani (Marylyn) Kaahanui, Clyde Haumea Kaahanui, Cyrus Kamea Aloha Kaahanui, Hiromi (Jeanette) Fukuzawa; daughters, Katherine Ku’ulei Kaahanui, Kathleen Kuuipo (Arthur) Sing, Karen Kehaulani Kaahanui; 14 grandchildren; 10 great-grandchildren; sister, Rebecca Leimomi Naha. Visitation 10:00 a.m. Thursday (7/19) at Mililani Downtown Mortuary, Funeral Service 11:00 a.m., Burial 2:00 p.m. at Hawaiian Memorial Park Cemetery. Casual Attire. Flowers Welcome. [Honolulu Star-Advertiser 17 July 2012] Kaahanui, Agnes Lily Kahihiulaokalani, June 14, 2012 Agnes Lily Kahihiulaokalani Kaahanui, 77, of Honolulu, a retired Iolani Palace maintenance housekeeping worker, died in Kuakini Medical Center. She was born in Honolulu. She is survived by sons Clifford K., Clyde H. and Cyrus K. Kaahanui, and Hiromi Fukuzawa; daughters Katherine K. and Karen K. Kaahanui, and Kathleen K. Sing; sister Rebecca L. Naha; 14 grandchildren; and 10 great- grandchildren. Visitation: 10 a.m. Thursday at Mililani Downtown Mortuary. Services: 11 a.m. Burial: 2 p.m. at Hawaiian Memorial Park. Casual attire. Flowers welcome. [Honolulu Star- Advertiser 17 July 2012] Kaahanui, Carolyn Luana, July 21, 2012 Carolyn Luana Kaahanui, 59, of Kahului, a Makena Surf housekeeping department employee, died in Maui Memorial Medical Center. -
March 21–25, 2016
FORTY-SEVENTH LUNAR AND PLANETARY SCIENCE CONFERENCE PROGRAM OF TECHNICAL SESSIONS MARCH 21–25, 2016 The Woodlands Waterway Marriott Hotel and Convention Center The Woodlands, Texas INSTITUTIONAL SUPPORT Universities Space Research Association Lunar and Planetary Institute National Aeronautics and Space Administration CONFERENCE CO-CHAIRS Stephen Mackwell, Lunar and Planetary Institute Eileen Stansbery, NASA Johnson Space Center PROGRAM COMMITTEE CHAIRS David Draper, NASA Johnson Space Center Walter Kiefer, Lunar and Planetary Institute PROGRAM COMMITTEE P. Doug Archer, NASA Johnson Space Center Nicolas LeCorvec, Lunar and Planetary Institute Katherine Bermingham, University of Maryland Yo Matsubara, Smithsonian Institute Janice Bishop, SETI and NASA Ames Research Center Francis McCubbin, NASA Johnson Space Center Jeremy Boyce, University of California, Los Angeles Andrew Needham, Carnegie Institution of Washington Lisa Danielson, NASA Johnson Space Center Lan-Anh Nguyen, NASA Johnson Space Center Deepak Dhingra, University of Idaho Paul Niles, NASA Johnson Space Center Stephen Elardo, Carnegie Institution of Washington Dorothy Oehler, NASA Johnson Space Center Marc Fries, NASA Johnson Space Center D. Alex Patthoff, Jet Propulsion Laboratory Cyrena Goodrich, Lunar and Planetary Institute Elizabeth Rampe, Aerodyne Industries, Jacobs JETS at John Gruener, NASA Johnson Space Center NASA Johnson Space Center Justin Hagerty, U.S. Geological Survey Carol Raymond, Jet Propulsion Laboratory Lindsay Hays, Jet Propulsion Laboratory Paul Schenk, -
Abstracts of the 50Th DDA Meeting (Boulder, CO)
Abstracts of the 50th DDA Meeting (Boulder, CO) American Astronomical Society June, 2019 100 — Dynamics on Asteroids break-up event around a Lagrange point. 100.01 — Simulations of a Synthetic Eurybates 100.02 — High-Fidelity Testing of Binary Asteroid Collisional Family Formation with Applications to 1999 KW4 Timothy Holt1; David Nesvorny2; Jonathan Horner1; Alex B. Davis1; Daniel Scheeres1 Rachel King1; Brad Carter1; Leigh Brookshaw1 1 Aerospace Engineering Sciences, University of Colorado Boulder 1 Centre for Astrophysics, University of Southern Queensland (Boulder, Colorado, United States) (Longmont, Colorado, United States) 2 Southwest Research Institute (Boulder, Connecticut, United The commonly accepted formation process for asym- States) metric binary asteroids is the spin up and eventual fission of rubble pile asteroids as proposed by Walsh, Of the six recognized collisional families in the Jo- Richardson and Michel (Walsh et al., Nature 2008) vian Trojan swarms, the Eurybates family is the and Scheeres (Scheeres, Icarus 2007). In this theory largest, with over 200 recognized members. Located a rubble pile asteroid is spun up by YORP until it around the Jovian L4 Lagrange point, librations of reaches a critical spin rate and experiences a mass the members make this family an interesting study shedding event forming a close, low-eccentricity in orbital dynamics. The Jovian Trojans are thought satellite. Further work by Jacobson and Scheeres to have been captured during an early period of in- used a planar, two-ellipsoid model to analyze the stability in the Solar system. The parent body of the evolutionary pathways of such a formation event family, 3548 Eurybates is one of the targets for the from the moment the bodies initially fission (Jacob- LUCY spacecraft, and our work will provide a dy- son and Scheeres, Icarus 2011). -
1 Rotation Periods of Binary Asteroids with Large Separations
Rotation Periods of Binary Asteroids with Large Separations – Confronting the Escaping Ejecta Binaries Model with Observations a,b,* b a D. Polishook , N. Brosch , D. Prialnik a Department of Geophysics and Planetary Sciences, Tel-Aviv University, Israel. b The Wise Observatory and the School of Physics and Astronomy, Tel-Aviv University, Israel. * Corresponding author: David Polishook, [email protected] Abstract Durda et al. (2004), using numerical models, suggested that binary asteroids with large separation, called Escaping Ejecta Binaries (EEBs), can be created by fragments ejected from a disruptive impact event. It is thought that six binary asteroids recently discovered might be EEBs because of the high separation between their components (~100 > a/Rp > ~20). However, the rotation periods of four out of the six objects measured by our group and others and presented here show that these suspected EEBs have fast rotation rates of 2.5 to 4 hours. Because of the small size of the components of these binary asteroids, linked with this fast spinning, we conclude that the rotational-fission mechanism, which is a result of the thermal YORP effect, is the most likely formation scenario. Moreover, scaling the YORP effect for these objects shows that its timescale is shorter than the estimated ages of the three relevant Hirayama families hosting these binary asteroids. Therefore, only the largest (D~19 km) suspected asteroid, (317) Roxane , could be, in fact, the only known EEB. In addition, our results confirm the triple nature of (3749) Balam by measuring mutual events on its lightcurve that match the orbital period of a nearby satellite in addition to its distant companion. -
1950 Da, 205, 269 1979 Va, 230 1991 Ry16, 183 1992 Kd, 61 1992
Cambridge University Press 978-1-107-09684-4 — Asteroids Thomas H. Burbine Index More Information 356 Index 1950 DA, 205, 269 single scattering, 142, 143, 144, 145 1979 VA, 230 visual Bond, 7 1991 RY16, 183 visual geometric, 7, 27, 28, 163, 185, 189, 190, 1992 KD, 61 191, 192, 192, 253 1992 QB1, 233, 234 Alexandra, 59 1993 FW, 234 altitude, 49 1994 JR1, 239, 275 Alvarez, Luis, 258 1999 JU3, 61 Alvarez, Walter, 258 1999 RL95, 183 amino acid, 81 1999 RQ36, 61 ammonia, 223, 301 2000 DP107, 274, 304 amoeboid olivine aggregate, 83 2000 GD65, 205 Amor, 251 2001 QR322, 232 Amor group, 251 2003 EH1, 107 Anacostia, 179 2007 PA8, 207 Anand, Viswanathan, 62 2008 TC3, 264, 265 Angelina, 175 2010 JL88, 205 angrite, 87, 101, 110, 126, 168 2010 TK7, 231 Annefrank, 274, 275, 289 2011 QF99, 232 Antarctic Search for Meteorites (ANSMET), 71 2012 DA14, 108 Antarctica, 69–71 2012 VP113, 233, 244 aphelion, 30, 251 2013 TX68, 64 APL, 275, 292 2014 AA, 264, 265 Apohele group, 251 2014 RC, 205 Apollo, 179, 180, 251 Apollo group, 230, 251 absorption band, 135–6, 137–40, 145–50, Apollo mission, 129, 262, 299 163, 184 Apophis, 20, 269, 270 acapulcoite/ lodranite, 87, 90, 103, 110, 168, 285 Aquitania, 179 Achilles, 232 Arecibo Observatory, 206 achondrite, 84, 86, 116, 187 Aristarchus, 29 primitive, 84, 86, 103–4, 287 Asporina, 177 Adamcarolla, 62 asteroid chronology function, 262 Adeona family, 198 Asteroid Zoo, 54 Aeternitas, 177 Astraea, 53 Agnia family, 170, 198 Astronautica, 61 AKARI satellite, 192 Aten, 251 alabandite, 76, 101 Aten group, 251 Alauda family, 198 Atira, 251 albedo, 7, 21, 27, 185–6 Atira group, 251 Bond, 7, 8, 9, 28, 189 atmosphere, 1, 3, 8, 43, 66, 68, 265 geometric, 7 A- type, 163, 165, 167, 169, 170, 177–8, 192 356 © in this web service Cambridge University Press www.cambridge.org Cambridge University Press 978-1-107-09684-4 — Asteroids Thomas H.