Comet Shoemaker–Levy 9 its orbit became more accurately established, the possibility of a collision became a certainty. The collision would provide a unique opportunity for scientists to look inside Jupiter's atmosphere, as the collisions were expected to cause eruptions of material from the layers normally hidden beneath the clouds. Astronomers estimated that the visible fragments of SL9 ranged in size from a few hundred metres (around ) to across, suggesting that the original comet may have had a nucleus up to across—somewhat larger than Comet Hyakutake, which became very bright when it passed close to the Earth in 1996. One of the great
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