A fragment of asteroid 2008 TC3 as found in the desert in northern Sudan in March 2009. The asteroid disintegrated at an altitude of 37 km in October 2008 but, remarkably, 47 fragments with a total mass of 3.95 kg have been recovered, and Jenniskens et al. have identified the material as surface matter from a class ‘F’ asteroid, a type not previously represented in meteorite collections. [Credit: Peter Jenniskens/ SETI Institute.]
Nature 458, 485-488 (26 March 2009)
Received 6 February 2009
Accepted 20 February 2009
Letter
The impact and recovery of asteroid 2008 TC3
P. Jenniskens1, M. H. Shaddad2, D. Numan2, S. Elsir3, A. M. Kudoda2, M. E. Zolensky4, L. Le4,5, G. A. Robinson4,5, J. M. Friedrich6,7, D. Rumble8, A. Steele8, S. R. Chesley9, A. Fitzsimmons10, S. Duddy10, H. H. Hsieh10, G. Ramsay11, P. G. Brown12, W. N. Edwards12, E. Tagliaferri13, M. B. Boslough14, R. E. Spalding14, R. Dantowitz15, M. Kozubal15, P. Pravec16, J. Borovicka16, Z. Charvat17, J. Vaubaillon18, J. Kuiper19, J. Albers1, J. L. Bishop1, R. L. Mancinelli1, S. A. Sandford20, S. N. Milam20, M. Nuevo20 & S. P. Worden20
1. SETI Institute, Carl Sagan Center, 515 North Whisman Road, Mountain View, California 94043, USA
2. Physics Department, University of Khartoum, PO Box 321, Khartoum 11115, Sudan
3. Physics Department, Juba University, Juba, Sudan
4. NASA Johnson Space Center, Mail Code KT, Houston, Texas 77058, USA
5. Jacobs Technologies Engineering Science Contact Group (ESCG), Johnson Space Center, Houston, Texas 77058, USA
6. Department of Chemistry, Fordham University, 441 East Fordham Road, Bronx, New York 10458, USA
7. Department of Earth and Planetary Sciences, American Museum of Natural History, 79th Street at Central Park West, New York, New York 10024, USA
8. Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road, NW, Washington DC 20015-1305, USA
9. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109, USA
10. School of Mathematics and Physics, Queen's University Belfast, University Road, Belfast BT7 1NN, UK
11. Armagh Observatory, College Hill, Armagh BT61 9DG, UK
12. Department of Physics and Astronomy, University of Western Ontario, London, Ontario N6A 3K7, Canada
13. ET Space Systems, 5990 Worth Way, Camarillo, California 93012, USA
14. Sandia National Laboratories, PO Box 5800, Albuquerque, New Mexico 87185, USA
15. Clay Center Observatory, Dexter and Southfield Schools, 20 Newton Street, Brookline, Massachusetts 02445, USA
16. Astronomical Institute of the Academy of Sciences, Fric caronova 298, 25165 Ondr caronejov Observatory, Czech Republic
17. Czech Hydrometeorological Institute, Na Sabatce 17, 143 06 Praha 4, Czech Republic
18. Institut de Mécanique Céleste et de Calcul des Éphémérides, 77 avenue Denfert-Rochereau, 75014 Paris, France
19. Dutch Meteor Society, Akker 141, 3732 XD De Bilt, The Netherlands
20. NASA Ames Research Center, Mail Stop 245-6, Moffett Field, California 94035, USA
Correspondence to: P. Jenniskens1 Correspondence and requests for materials should be addressed to P.J. (Email: Petrus.M.Jenniskens@nasa.gov).
Abstract:
In the absence of a firm link between individual meteorites and their asteroidal parent bodies, asteroids are typically characterized only by their light reflection properties, and grouped accordingly into classes1, 2, 3. On 6 October 2008, a small asteroid was discovered with a flat reflectance spectrum in the 554–995 nm wavelength range, and designated 2008 TC3 (refs 4–6). It subsequently hit the Earth. Because it exploded at 37 km altitude, no macroscopic fragments were expected to survive. Here we report that a dedicated search along the approach trajectory recovered 47 meteorites, fragments of a single body named Almahata Sitta, with a total mass of 3.95 kg. Analysis of one of these meteorites shows it to be an achondrite, a polymict ureilite, anomalous in its class: ultra-fine-grained and porous, with large carbonaceous grains. The combined asteroid and meteorite reflectance spectra identify the asteroid as F class3, now firmly linked to dark carbon-rich anomalous ureilites, a material so fragile it was not previously represented in meteorite collections.
Link: Nature paper link
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