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Evolution of Igneous Asteroids: Focus on Vesta and the Hed Meteorites

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Evolution of Igneous Asteroids: Focus on Vesta and the Hed Meteorites '/,7 NASA-CR-204832 N A5A-{If-d()L/, f3;{ NASA-CR-204832 19970025927 WORKSHOP ON EVOLUTION OF IGNEOUS ASTEROIDS: FOCUS ON VESTA AND THE HED METEORITES 0 ;~ .'0\1L 'i - () , t - , • • ~ I" - .' ~ _ . ,,~, i. =-= LPI Technical Report Number 96-02, Part 1 Lunar and Planetary Institute 3600 Bay Area Boulevard Houston TX 77058-1113 ot -; ... LPIITR-96-02, Part 1 111111111111111111111111111111111111111111111 NF01381 ENTER: DISPLAY 97N25363/2 97N25363*# ISSUE 1 CATEGORY 90 RPT#: NASA-CR-204832 NAS 1.26:204832 LPI-96-02, PART 1 NIPS-97-32331 CNT#: NASW-4574 96/01/01 52 PAGES UNCLASSIFIED DOCUMENT UTTL: Workshop on Evolution of Igneous Asteroids: Focus on Vesta and the HED Meteorites AUTH: A/MITTLEFEHLDT, D. W.; B/PAPIKE, J. J. PAT: A/ed.; B/ed. CORP: Lunar and Planetary Inst., Houston, TX. SAP: Avail: CASI HC A04/MF AOl; Abstract Only CIO: UNITED STATES Presented at Workshop on Igneous Asteroids, Houston, TX, United States, 16-18 Oct. 1996; Sponsored by Lunar and Planetary Inst., MAJS: /*ASTEROIDS/*ASTRONOMY/*CONFERENCES/*GEOLOGICAL SURVEYS/*MAPPING/* SPECTROSCOPY/*VESTA ASTEROID MINS: / COLLISIONS/ HEATING/ HUBBLE SPACE TELESCOPE/ METEORITES/ MINERALOGY/ RADIOACTIVE ISOTOPES/ SPACE MISSIONS -, ABA: Derived from text J4c)lOO~'59~ I ABS: This volume contains papers that have been accepted for presentation at the Workshop. Topics considered include: On the sample return from Vesta by low-thrust spacecraft; Astronomical evidence linking Vesta to the HED meteorites; Geologic mapping of Vesta with the Hubble Space Telescope; A space mission to Vesta; Asteroid spectroscopy; The thermal history of asteroid 4 Vesta, based on radionuclide and collision heating; Mineralogical records of early planetary processes on Vesta. ____ E1\1_'T'.ER~ ... _...... WORKSHOP ON EVOLUTION OF IGNEOUS ASTEROIDS: FOCUS ON VESTA AND THE HED METEORITES Edited by D. W. Mittlefehldt and J. J. Pap ike [IBRARY COPV I i. l'.! I Held at LANGLEY RESEARCH CENTER Houston, Texas UBRARYNASA HAMPTON, VIRGINIA October 16-18, 1996 Sponsored by Lunar and Planetary Institute Lunar and Planetary Institute 3600 Bay Area Boulevard Houston TX 77058-1113 LPI Technical Report Number 96-02, Part 1 LPJJTR--96-02, Part 1 Compiled in 1996 by LUNAR AND PLANETARY INSTITIITE The Institute is operated by the Universities Space Research Association under Contract No. NASW-4574 with the National Aeronautics and Space Administration. Material in this volume may be copied without restraint for library, abstract service, education, or personal research purposes; however, republication of any paper or portion thereof requires the written permission of the authors as well as the appropriate acknowledgment of this publication. This report may be cited as Mittlefehldt D. W. and Papike J. J., eds. (1996) Worbhop on Igneous Asteroids: Focus on Vesta and the HED Meteorites. LPI Tech. Rpt. 96-02, Part 1, Lunar and Planetary Institute, Houston. 44 pp. This report is distributed by ORDER DEPARTMENT Lunar and Planetary Institute 3600 Bay Area Boulevard Houston TX 77058-1113 Mail order requestors will be invoiced for the cost of shipping and handling. LPI Technical Report 96-02, Part I iii Preface This volume contains papers that have been accepted for presentation at the Workshop on Evolution ofIgneous Asteroids: Focus on Vesta and the RED Meteorites, October 16-18, 1996, in Houston, Texas. The organizers for this workshop were David Mittlefehldt from NASA Johnson Space Center, and James Papike from the University of New Mexico. Logistics and administrative and publications support were provided by the Publications and Program Services Department staff at the Lunar and Planetary Institute. LPI Technical Report 96-02, Part I v Contents On the Sample Return from Vesta by Low-Thrust Spacecraft R. Z. Akhmetshin, T. M. Eneev, and G. B. Efimov ............................................................................. 1 Vesta: The Big Questions J. F. Bell ............................................................................................................................................. 1 Astronomical Evidence Linking Vesta to the RED Meteorites: A Review R. P. Binzel .................................................................................................................... ~ .................... 2 Geologic Mapping of Vesta with the Hubble Space Telescope R. P. Binzel, M. J. Gaffey, P. C. Thomas, B. H. Zellner, A. D. Storrs, and E. N. Wells ................................................................................................................................... 2 Early Energetic Particle Irradiation of the HED Parent Body Regolith D. D. Bogard, D. H. Garrison, and M. N. Rao .................................................................................. 2 Automated SEM Modal Analysis Applied to the Diogenites L. E. Bowman, M. N. Spilde, and J. J. Papike ............................. :........ : ............................................ 3 A Space Mission to Vesta: General Considerations L. Bussolino, R. Sommat, C. Casaccit, V. Zappala, A. Cellino, and M. Di Martino .............................................................................................................................. 5 Cosmogonic Implications of the HED-Vesta Connection G. J. Consolmagno Sf ........................................................................................................................ 6 Disrupting and Destroying Families from Differentiated Parent Bodies D. R. Davis, P. Farinella, F. Marzari, and E. Ryan .......................................................................... 6 Mapping Vesta in the Visible and Near-Infrared: The 1994 and 1996 Oppositions as Viewed from the Ground C. Dumas and O. R. Hainaut .............................................................................................................. 7 Asteroid Spectroscopy: Vesta, the Basaltic Achondrites, and Other Differentiated Asteroids M. J. Gaffey ........................................................................................................................................ 8 The Thermal History of Asteroid 4 Vesta, Based on Radionuclide and Collisional Heating A. Ghosh and H. Y. McSween Jr. ....................................................................................................... 9 The Content and Isotopic Composition of Carbon in HED Basaltic Achondrites M. M. Grady, I. P. Wright, and C. T. Pillinger ................................................................................ 10 vi WorksJwp on Evolution ofIgneous Asteroids Noncumulate vs. Cumulate Eucrites: Heterogeneity of 4 Vesta w. Hsu and G. Crozaz ...................................................................................................................... 11 Isotopic Constraints on the Origin of Eucrites M. Humayun and R. N. Clayton ....................................................................................................... 12 Multispectral Light Curves of Vesta R. Jaumann, A. Nathues, S. Mottola, and H. Hoffmann ...........................................................: ...... 13 The Origin of Eucrites: An Experimental Perspective J. H. Jones, D. W. Mittlefehldt, A. J. G. Jurewicz, H. V. Lauer Jr., B. Z. Hanson, C. R. Paslick, and G. A. McKay ................................................................................ 15 Practical Evaluation of Regolith Maturation Processes L. Ksanfomality and W. K. Hartmann ............................................................................................... 16 The Vesta Asteroid Family: Origin and Evolution F. Marzari, A. Cellino, D. R. Davis, P. Farinella, V. Zappala, and V. Vanzani ............................. 16 A Dynamical Study of Vesta-Family Fragments F. Migliorini, V. Zappala, A. Morbidelli, and A. Cellino ................................................................ 17 Core Formation in the Howardite-Eucrite-Diogenite Parent Body (Vesta) H. E. Newsom ................................................................................................................................... 17 Pyroxene Homogenization and the Isotopic Systematics of Eucrites L. E. Nyquist and D. D. Bogard ....................................................................................................... 18 Diogenites: Cumulates from Asteroid 4 Vesta-Insights from Orthopyroxene and Spinel Chemistry J. J. Papike, L. E. Bowman, M. N. Spilde, G. W. Fowler, and C. K. Shearer ................................. 19 Shape and Albedo Variations of Asteroid 4 Vesta K. L. Reed, M. J. Gaffey, and L. A. Lebofsky ................................................................................... 20 Core Formation in Vesta K. Righter and M. J. Drake .............................................................................................................. 21 Asteroid 4 Vesta as the RED Parent Body: Implications for a Metallic Core and Magma Ocean Crystallization A. Ruzicka, G. A. Snyder, and L. A. Taylor ...................................................................................... 23 The Composition of the Eucrite Parent Body: Implications for the Origin of the Moon and for Planetary Accretion A. Ruzicka, G. A. Snyder, and L. A. Taylor ...................................................................................... 24 LPI Technical Report 96-02. Part I vii REE Partition Coefficients from Synthetic Diogenite-like Enstatite and the Implications of Petrogenetic Modeling C. S. Schwandt and G. A. McKay ....................................................................................................
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