Chinese, Greek, and many other ancient cultures left references in their texts to the sky going dark during the day, possible allusions to solar eclipses. These mentions are tantalizing clues to scientists, who think they might use those clues to date historical events. The latest buzz in historical dating started this week, when researchers Marcelo Magnasco and Constantino Baikouzis said they had tied an event in Homer's Odyssey, the hero Odysseus' return to Ithaca [strike]Italy [/strike]after a two-decade journey, to a total solar eclipse on April 16, 1178 B.C. But how could they be so exact? First, knowing the motions of the Earth and the moon allows astronomers to project when solar eclipses are coming down to the day, time, and location. They can use the same techniques to go backward, pinning down dates and approximate locations for millennia-old astronomical events, and that's when the historians and archaeologists get excited. In the 1800s, Henry Rawlinson of Britain tied a known 763 B.C. eclipse that darkened much of the Middle East to a reference in a text of the Assyrian Empire about the sun being blocked out. Historians have subsequently used that date as a basis to date other events in the ancient world. You can see NASA's whole list of eclipses and possible historical tie-ins here. In the 1920s, The Guardian says, scientists calculated that there had been a solar eclipse over the Odysseus' supposed home on the Ionian Sea in 1178 B.C. To dig deeper into a possible link to the Odyssey, Magnasco and Baikouzis scoured the text for other mentions of astronomical events around Odysseus' homecoming. They say that Homer mentioned a new moon the night before, Venus high in the sky six days before, Mercury at the west end of its trajectory 33 days before, and the constellations Pleiades and Bootes being visible at sunset. The only time those events happened in that pattern, the researchers say, was the day of the eclipse—April 16, 1178 B.C. However, Homeric astronomy is mythological and cryptic—the blind poet actually writes of Hermes, who corresponds to the Roman god Mercury, but doesn't specifically mention the planet. Even the text about the sun being blocked from the sky is vague, though historians have generally interpreted the meaning as an eclipse. So the researchers acknowledge that the Odyssey link is tenuous, but they're still excited. Now, if scientists find a skeleton of the Cyclops, we'll be in business.
Read more about the Odyssey study here.