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Comet Shoemaker-Levy 9: Fragment and progenitor impact energy

Takata, Toshiko and Ahrens, Thomas J. and Harris, Alan W. (1995) Comet Shoemaker-Levy 9: Fragment and progenitor impact energy. Geophysical Research Letters, 22 (17). pp. 2433-2436. ISSN 0094-8276. doi:10.1029/95GL02237.

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Initial observational data from the impact of fragments of Comet Shoemaker-Levy 9 (SL9) are compared with smoothed particle hydrodynamic (SPH) calculations to determine their pre-impact diameters and the equivalent diameter of the SL9 progenitor. Diameters (solid ice) of 2.0±0.1, 2.0±0.05, 2.1±0.04 and 1.9±0.05 km for fragments A, E, G1, and W are obtained from impact-induced plume heights from the Hubble Space Telescope (HST) data. Applying these values to scale apparent diameters for the balance of 18 SL fragments in Weaver et al.'s [1995] catalog of 22 objects yields a SL9 progenitor diameter of 5.0±1.8 km. This corresponds to total impact energy of 1.2 (+1.8−0.8) × 10^(30) erg. Such an energetic event occurs on Jupiter and Earth at least every 4,900 +4,700, −2,700, and ∼0.5 × 10^8 years, respectively.

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Harris, Alan W.0000-0001-7431-2013
Additional Information:© 1995 by the American Geophysical Union. Paper number 95GL02237. Received: February 16, 1995; revised: June 26, 1995; accepted: July 10, 1995. We thank Glenn Orton, James Friedson, Andrew Ingersoll, Reta Beebe, Heidi Hammel, Paul R. Weissman and the HST team for directing us to data and helpful discussion, and Eugene M. Shoemaker, Paul R. Weissman, Carolyn S. Shoemaker, George Field, and A. Ferrara for their preprints. We thank reviewer, M. Boslough, an anonymous reviewer, and W. Anderson for comments on the manuscript. Research supported by NASA. Contribution No. 5462, Division of Geological and Planetary Sciences, California Institute of Technology.
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Caltech Division of Geological and Planetary Sciences5642
Issue or Number:17
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ID Code:50807
Deposited By: Tony Diaz
Deposited On:24 Oct 2014 22:41
Last Modified:10 Nov 2021 19:01

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