May 28, 585 BC: The Battle Of The Solar Eclipse

On May 28, 585 BC, a solar eclipse was predicted by the Greek mathematician and philosopher Thales according to the historian Herodotus. It is purported that the eclipse was the factor. the halted the war etween King Aylattes of Lydia and the forces of King Cyaxares of Medes. A short excerpt from the article:

"The Mechanics of a Monumentally Difficult Prediction

The reason this astronomical event is thought of as being so important is that predicting a solar eclipse , compared with a lunar eclipse , is exceptionally difficult. The astronomer must not only calculate when it will occur, but where on Earth’s surface it will be visible and according to NASA, in a lunar eclipse the moon passes through the Earth's sun shadow and the phenomena is visible on the whole side of the Earth that is in nighttime, and they often last longer than an hour. In solar eclipses, however, the moon's shadow falls across the Earth in a comparatively narrow path with a maximum duration at any given location of about 7½ minutes.

So to accurately calculate a solar eclipse the observer requires an intimate understanding of the Moon's orbit around Earth to within fractions of a degree of accuracy, and what makes Thales’ prediction a historical mystery is that historians know early Greeks , at large, didn’t have this essential lunar data and there are no other records of Greek astronomers in this period accurately predicting any other eclipses. Thus, it is thought by historians that the only place Thales’ advanced astronomical knowledge could have come from was Egypt.

The Birth of Geometry and Astronomy

Historians Herodotus (c. 450 BC) and Strabo (c. 24 BC) both said Greek mathematicians adapted many of the Egyptian calculation and surveying techniques, modifying and developing them with their own sophisticated advancements into a very refined system. Furthermore, it's known Thales studied Egyptian techniques for measuring sections of land with rope, and when his notes were transferred onto clay tablets by Greek geometers, and later codified by Euclid, geometry was born ( Geo -“Earth” and Metry -“Measure” in Greek).

Having learned so many practical mathematical skills, like bisecting angles, trigonometry and calculating passing time using shadows, from Egyptian surveyors, some researchers speculate that Thales may not have made the famous eclipse prediction himself, but may simply have lifted the date from the Egyptians."