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Comment by lordnacho | Hacker News Reader

I heard somewhere that the Spanish managed to wow the people they met in the new world with an eclipse.

Is this true? What calculations did they do to figure this out with 16th century math?

A bit tangential, but this was one of the main ways that the Jesuits were able to gain access to the Imperial Court in Ming Era China. Predicting solar eclipses was one of the most important functions of the royal astronomers. However from the late Song Dynasty and into the Ming Dynasty there was some bureaucratic decay in the Astronomical Bureau and the quality of eclipse predictions declined. When the Jesuits arrived they were able to make superior eclipse predictions and leveraged that to gain appointments to the astronomical bureau. (And they were so successful at this that the Bureau was run by a Jesuit for a century and a half.)

Incidentally, this didn't work everywhere Europeans went. When Guillaume Le Gentil arrived in southern India in the 18th century he found that Tamil eclipse prediction techniques were superior to the Western methods. (His own prediction was off by 68 seconds whereas the Tamil prediction was off by 41 seconds.)

If they were familiar with Ptoloemy's almagest, they would be able to predict eclipses using geometric methods. Not perfect but surprisingly accurate according to Jayant Shah in the paper "Accuracy of Ptolemy’s Almagest in predicting solar eclipses"

More accurate methods using Newton's theories were yet to come.

Christopher Columbus did it to terrorize people into giving him food (lunar eclipse, not solar): https://en.wikipedia.org/wiki/March_1504_lunar_eclipse

Geez, what an ass hole.

He did alright.

Lunar, not solar. No one worked out how to accurately predict the time and, more importantly, location of solar eclipses until Halley in 1715. [1]

1. https://www.quantamagazine.org/how-the-ancient-art-of-eclips...

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