Halley's Comet repeats every 75–76 years and is (most recently) just a bit more than 3 miles diameter. Either it started out really, really a lot larger, or it hasn't been on the same orbit for all that long. Anyway, bravo!
[snip] The first known observation of Halley's took place in 239 B.C., according to the European Space Agency. Chinese astronomers recorded its passage in the Shih Chi and Wen Hsien Thung Khao chronicles. Another study (based on models of Halley's orbit) pushes that first observation back to 466 B.C., which would have made it visible by the Ancient Greeks.
When Halley's returned in 164 B.C. and 87 B.C., it probably was noted in Babylonian records now housed at the British Museum in London. "These texts have important bearing on the orbital motion of the comet in the ancient past," noted a Nature research paper about the tablets.
This portion of the Bayeux Tapestry shows Halley's Comet during its appearance in 1066.
Another appearance of the comet in 1301 possibly inspired Italian painter Giotto's rendering of the Star of Bethlehem in "The Adoration of the Magi," according to the Britannica encyclopedia.Halley's most famous appearance occurred shortly before the 1066 invasion of England by William the Conqueror. It is said that William believed the comet heralded his success. In any case, the comet was put on the Bayeux Tapestry — which chronicles the invasion — in William's honor.
Astronomers in these times, however, saw each appearance of Halley's Comet as an isolated event. Comets were often foreseen as a sign of great disaster or change.
Even when Shakespeare wrote his play "Julius Caesar" around 1600, just 105 years before Edmond Halley calculated that the comet returns over and over again, one famous phrase spoke of comets as heralds: "When beggars die there are no comets seen; The heavens themselves blaze forth the death of princes." [/snip]Halley's Comet: Facts About the Most Famous Comet By Elizabeth Howell over 3 years ago