What are the sizes of the fragments?
Using measurements of the length of the train of fragments and a model for the tidal disruption, J.V. Scotti and H.J. Melosh have estimated that the parent nucleus of the comet (before breakup) was only about 2 km across [13]. This would imply that the individual fragments are no larger than about 500 meters across. Images of the comet taken with the Hubble Space Telescope in July 1993 indicate that the fragments are 3-4 km in diameter (3-4 km is an upper limit based on their brightness; the fragments have visual magnitudes of around 23). A more elaborate tidal disruption model by Sekanina, Chodas and Yeomans [20] predicts that the original comet nucleus was at least 10 km in diameter. This means the largest fragments could be 3-4 km across, a size consistent with estimates derived from the Hubble Space Telescope’s July 1993 observations. The new images, taken with the Hubble telescope’s new Wide Field and Planetary Camera-II instrument in 1994, have given us an even clearer view of th
