Comet Shoemaker–Levy 9 electrons—electrons with velocities near the speed of light—into the Jovian magnetosphere by the impacts. About an hour after fragment K entered Jupiter, observers recorded auroral emission near the impact region, as well as at the antipode of the impact site with respect to Jupiter's strong magnetic field. The cause of these emissions was difficult to establish due to a lack of knowledge of Jupiter's internal magnetic field and of the geometry of the impact sites. One possible explanation was that upwardly accelerating shock waves from the impact accelerated charged particles enough to cause auroral emission, a phenomenon more typically associated
Great Comet of 1744 "dust striae" seen in the tails of some comets, such as Comet West and C/2006 P1 (McNaught). Chéseaux, on March 9, was the last known observer in the northern hemisphere to see the comet, but it remained visible for observers in the southern hemisphere, some of whom reported a tail length of approximately 90 degrees on March 18. The comet was not seen after April 22, 1744. The comet also was noted in Japanese astronomical records in the "Nihon Odai Ichiran" of the Kanpō era. Researchers have found in Chinese astronomical records that some Chinese observations describe audible sounds associated