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Workshop on Evolution of Igneous Asteroids, Focus on Vesta and the HED Meteorites

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Workshop on Evolution of Igneous Asteroids, Focus on Vesta and the HED Meteorites WORKSHOP ON EVOLUTION OF IGNEOUS ASTEROIDS: FOCUS ON VESTA AND THE HED METEORITES !!! LPI Technical Report Number 96-02, Part 1 Lunar and Planetary Institute 3600 Bay Area Boulevard Houston TX 77058-1113 o;-<; _ LPIITR--96-02, Part 1 WORKSHOP ON EVOLUTION OF IGNEOUS ASTEROIDS: FOCUS ON VESTA AND THE HED METEORITES Edited by D. W. Mittlefeh1dt and J. J. Papike Held at Houston, Texas 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 LPIITR--96-02, Part 1 Compiled in 1996 by LUNAR AND PLANETARY INSTITUTE The Institute is operated by the Universities Space Research Association under Contract No. NASW-4S74 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 pennission of the authors as well as the appropriate acknowledgment of this publication. This report may be cited as Mittlefehldt D. W. and Pap ike J. J., eds. (1996) Workshop on Igneous Asteroids: Focus on Vesta and the HED Meteorites. LPI Tech. Rpt. 96-02, Part I, 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 1 iii Preface This volume contains papers that have been accepted for presentation at the Workshop on Evolution ofIgneous Asteroids: Focus on Vesta and the HED Meteorites, October 16-18, 1996, in Houston, Texas. The organizers for this workshop were David Mittlefehldt from NASA Johnson Space Center, and James Pap ike 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 1 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 HED 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 1. 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 RED-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 Workshop on Evo/ution 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. Mittlejehldt, 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. Ksanjomality 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 Fonnation 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. Lebojsky ................................................................................... 20 Core Fonnation in Vesta K. Righter and M. J. Drake .............................. ................................................................................ 21 Asteroid 4 Vesta as the HED 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, Parr I vii REE Partition Coefficients from Synthetic Diogenite-like Enstatite and the Implications ofPetrogenetic Modeling C. S. Schwandt and G. A. McKay .................. .................................... ............................................... 25 Metamorphism of Eucrites and Eucrite-related Meteorites and Implications for Parent Body Sources D. W. G. Sears, S. J. K. Symes, and P. H. Benoit ............................................................................. 27 Petrogenetic Models for the Origin of Diogenites and Their Relationship to Basaltic Magmatism on the HED Parent Body C. K. Shearer, G. Fowler, andJ. 1. Pap ike ........................... ........................................ ................... 28 Is There Another Link in the Chain? Looking for Streams of HED Meteorites T. D. Swindle, R. Lippse, and I. Scott ............................................................................................... 30 Mineralogical Records of Early Planetary Processes of the HED Parent Body H. Takeda ......................................................................................................................................... 30 Eucrites, Terrestrial Basalts, and Volcanic Processes on Vesta G. 1. Taylor, R. C. Friedman, andA. Yamaguchi ............................................................................ 31 Vesta: Spin Pole, Size, and Shape from HST Images P. C. Thomas, R. P. Binzel, M. J. Gaffey, B. H. Zellner, A. D. Storrs, and E. Wells ...................................................................................................................................... 32
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