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Tidal breakup of the nucleus of Comet Shoemaker—Levy 9

Published online by Cambridge University Press:  02 August 2016

Zdenek Sekanina*
Affiliation:
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA

Abstract

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The breakup of Comet Shoemaker-Levy 9 is discussed both in the context of splitting as a cometary phenomenon, comparing this object with other split comets, and as an event with its own idiosyncrasies. The physical appearance of the comet is described, features diagnostic of the nature of tidal splitting are identified, and the implications for modelling the event are spelled out. Among the emphasized issues is the problem of secondary fragmentation, which documents the comet's continuing disintegration during 1992-94 and implies that in July 1992 the parent object split tidally near Jupiter into 10-12, not 21, major fragments. Also addressed are the controversies involving models of a strengthless agglomerate versus a discrete cohesive mass and estimates for the sizes of the progenitor and its fragments.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1996

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