Why was it so important that al- battanis work was translated into Latin

Latin, unlike Arabic or the original Greek, was a language that any educated European could read during Galileo's time.

Explanation:

Latin was a language that learned Europeans, at this time in Europe, could read and understand as it was the language of the Roman Catholic Church. Galileo appreciated that the Muslims had saved the great works of the Greeks and Romans which would have otherwise have been destroyed by the Catholic Church at the start of the Middle Ages. These saved manuscripts were saved with both the original Greek and Latin and Arabic translation in the texts.

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