COMETARY SPLITTING - A SOURCE FOR THE JUPITER FAMILY

The quest for the origin of the Jupiter family of comets includes inve stigating the possibility that a large fraction of this population ori ginates from past splitting events. In particular, one suggested scena rio, albeit less attractive on physical grounds, maintains that a gian t comet breakup is a major source of short-period comets. By simulatin g such events and integrating the motions of the fictitious fragments in an accurate solar system model for the typical lifetime of Jupiter family comets, it is possible to check whether the outcome may or may not be compatible with the observed orbital distribution. In this pape r we present such integrations for a few typical progenitor orbits and analyze the ensuing thermalization process with particular attention to the Tisserand parameters. It is found that the sets of fragments lo se their memory of a common origin very rapidly so that, in general te rms, it is difficult to use the random appearance of the observed orbi tal distribution as evidence against the giant comet splitting hypothe sis.