The impact of comet Shoemaker-Levy 9 on the Jovian ionosphere and aurorae

We outline the effects of a "typical" fragment of Comet Shoemaker-Levy 9 on the ionosphere and aurorae of Jupiter, viewed chronologically from approach, through impact to longer term effects. The ionosphere is found to have been a sensitive tracer of the impact events. The powerful jovian magnetic field transmitted the effects of the collisions across hemispheres. Electrodynamical processes were particularly important around the time of fragment impact, along with shock heating of the ionosphere. Chemical reactions not usual in the jovian upper atmosphere prayed a key role in diminishing ionospheric and auroral emission intensities. (C) 1997 Elsevier Science Ltd. All rights reserved