in the summer of 65 or in the following winter of 65–66. The Chinese record 2 comets: one in July 65 which remained visible for 56 days, and the other in February 66 which remained visible 50 days.
Hind suggested that most likely the last-named was Halley's Comet, if the perihelion passage took place at the end of January, and Cowell and Crommelin have definitely confirmed this. Not improbably this comet was the sword-shaped sign recorded as having hung over the city of Jerusalem before the commencement of the war which terminated in the destruction of the Holy City. Josephus says that several prodigies announced the destruction of Jerusalem:—"Amongst other warnings, a comet, of the kind called Xiphias, because their tails appear to represent the blade of a sword, was seen above the city for the space of a whole year[1]." Josephus rebuked his countrymen for listening to false prophets while so notable a sign was in the heavens.
Dion Cassius mentions a comet which seemed to be suspended over the city of Rome before the death of Agrippa. The date would be B.C. 11. The path of this comet was recorded in great detail by the Chinese, and Hind thought that the records afforded "the most satisfactory proof that they belonged to the Comet of Halley". The 3rd week in October was suggested for the perihelion passage. The comet was lost in the Sun's rays 56 days after its discovery.
Cowell and Crommelin have made systematic efforts to trace Halley's Comet back further, and with some success, and it is not beyond the bounds of possibility that further identification will reward research because the Chinese records go back for six centuries before the Christian era, and besides them there exists a sprinkling of European observations, although all these latter are very much lacking both in precision of language and precision of dates.
The danger of jumping at conclusions in the case of astronomy (as indeed in everything else) is painfully shown
- ↑ Bella Judæorum, lib. vi, § 5.
