COMET SPLITTING - OBSERVATIONS AND MODEL SCENARIOS

摘要: Splitting events affect cometary nuclei to a different level of severity ranging from complete disruption the nucleus (e.g., C/1999 S4 LINEAR) separation major fragments 73P/Schwassmann—Wachmann 3) and spill-offs smaller boulders C/2001 A2 LINEAR). Fragmentation comets produces secondary products over wide range sizes (from cometesimals sub-micron dust). It is detectable through presence (with own comae tails) in coma parent nucleus, outbursts its activity arc-lets (“coma wings”) associated with fragments. The secondaries have lifetimes show non-gravitational forces. Nucleus splitting also considered generate whole families (Kreutz group) or — if gravitational bound multiple C/1995 O1 Hale—Bopp). may explain striae phenomena seen dust tails bright (C 1995 Hale—Bopp) detection chains impact craters on other bodies solar system. As process significant mass loss it relevant for scenario extinction, at same time plays role number statistics existing (observable) size distribution comet nuclei. Various model scenarios are proposed: tidal disruption, rotational splitting, break-up due internal gas pressure, fragmentation collision bodies. Only one case, Comet D/1993 F1 Shoemaker—Levy 9, physical could be undoubtedly identified. In any provides important insights structure, surface layering chemistry