eclipse: 1504

In the early months of 1504 Christopher Columbus was stuck in unseaworthy ships on the north coast of Jamaica, at the end of his 4th voyage in the Caribbean. No response had been received to appeals for rescue made to the Spaniards in Hispaniola. The local Tainos were getting tired of supplying food to the big-eaters on the beached ships. Columbus needed to stave off the threat of starvation, and turned to an Ephemerides of Johannes Regiomontanus which he apparently had with him; this set out, among other information, the dates of lunar eclipses between 1475 and 1506. Columbus was interested in lunar eclipses because they provided at that time the main way of attempting to establish longitude; he wanted to work out the longitude of his discoveries to support his claim to have reached Asia. The Ephemerides predicted the occurrence of a lunar eclipse on the evening of February 29th [1504 was of course a leap year].

Since Columbus was not very sure of his actual longitude, he presumably just had to hope that he could judge the time of the appearance of the eclipse closely enough to make his scheme work. He summoned the leaders of the Tainos and solemnly warned them that if they did not promise to keep on supplying the Spaniards with food, his all-powerful God would punish them by taking away the moon. The Tainos were perhaps not particularly impressed [ many accounts suggest that some of them had the giggles at the idea], but when the moon was progressively covered by shadow and seemed to disappear, they began to panic and assured the Spaniards that the food would continue to arrive. Columbus stayed in his cabin, probably checking his calculations as to when the moon would re-emerge from the shadow, then he came out to assure the local leaders that God had accepted their promises, and that the moon would be returned. Which is all a very nice neat trick, if there is an eclipse conveniently at hand!

CELESTIAL PHENOMENA were observed by Columbus on several of his

voyages. He observed a "marvelous branch of fire" that fell into

the sea (a meteor or a comet?) in 1492 on his first voyage.... There was a total eclipse of the moon on September 14, 1494 (second voyage), which Columbus used to clarify his position (erroneously) near Asia. On the fourth voyage Columbus used his foreknowledge of a total eclipse of the moon on February 29, 1504, to convince the Indians of his supernatural powers.

Columbus Mythbusters