Usa travel for Concerning the Halley’s apparition of BC, Hunger et al. comment that, although the Babylonian astronomers no doubt analyzed the comet very closely, no trace of their records has survived. Chinese Records A major boon for students of the history of astronomy is the surviving records of celestial phenomena kept in the Far East, particularly in China and Korea. They provide an invaluable collection of cometary observations all the way back to the first millennium BC. For our purposes, however, the records we have from Korea are few and far between and of questionable reliability, and those from ancient China, largely preserved in a multivolume historical work known as the Han shu, while more numerous and reliable, are far from complete. There can be little doubt that the Chinese astronomers at the end of the irst century BC observed many, if not most, naked-eye comets. However, a large number of these reports were not available to the writers of the Han shu, either because they were not made the subjects of memorials to the emperor and therefore were not formally included in the court register, or because they had been lost in the subsequent period. Usa travel 2016.