A recent paper published in the Proceedings of the National Academy of Science, used astronomical references in Odyssey to find the date on which the Greek hero Odysseus returned to his wife Penelope. Using three non-allegorical astronomical references, the researchers searched for a date between 1250 – 1115 B.C.E. where the astronomical references cohered and found that a date of April 16, 1178 B.C.E matched perfectly.
The authors of the paper believe that Odyssey is fiction and it was interpolated with valid astronomical data. But Homer lived five centuries after the eclipse and it is a mystery how he would have known about that event. One theory suggested in the paper is that, if Homer knew about Metonic and Saros eclipse cycles, he could have estimated the eclipse.
In fact the Greeks had a mechanical device which could do exactly that. Though sponge divers discovered the device in 1901, it was only recently that many mysteries of its mysteries were solved. The device called the Antikythera mechanism was thought to be an ancient mechanical computer.
A paper in Nature reveals that one dial on the bronze mechanism is a 19 year calendar based on the Metonic cycle and all 12 months in the calendar were identified. Also it was found that the mechanism was sophisticated enought to know which years had 13 months and which months had 29 or 30 days. The Babylonians too had a Metonic cycle based calendar, but it was not this precise.
Another dial on the mechanism was found to be the Saros eclipse prediction dial with an excellent prediction scheme. 18 eclipse glyphs were marked on the dial and it gave a perfect match for 100 start dates.
Homer could not have known about this particular device since it is dated to 146 BCE, when Corith, where the device was created, fell to Romans. Homer is dated to 8th century BCE and so far so such devices dating to that period have been found. So the mystery of how Homer knew about eclipses five centuries before him still remains.