| Abstract: | This work is based on a systematic analysis of images of comet 1P/Halley collected during its penultimate and ultimate approaches, i.e., in 1910 and 1986. This research has identified, characterized, classified, and compared tail structures of comet 1P/Halley, namely disconnection events (DEs), wavy structures, and solitons. The images of the comet during its 1910 passage, as illustrated in the Atlas of Comet Halley 1910 II (Donn et al. 1986), were compared with those of its approach in 1986 as illustrated in The International Halley Watch Atlas of Large‐Scale Phenomena (Brandt et al. 1992). Two onsets of DEs were discovered after the perihelion passage in 1910 with an average value of the corrected cometocentric velocity (Vc) of 57 ± 15 km s?1. Ten onsets of DEs were discovered after the perihelion passage in 1986 with an average Vc equal to 130 ± 37 km s?1. The mean value of the corrected wavelength λc of wavy structures in 1910 is equal to 1.7 ± 0.1 × 106 km, as compared to 2.2 ± 0.2 × 106 km in 1986. The mean value of the amplitude A of the wave in 1910 is equal to 1.4 ± 0.1 × 105 km and 2.8 ± 0.5 × 105 km in 1986. The goals of this research were to report the results obtained from the analysis of the P/Halley's images from 1910 and 1986, to provide empirical data for comparison, and to form the input for future physical/theoretical work. |
