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Convert hipparchic cycle to lustre (Lustrum)
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Definition and details for hipparchic cycle:
Hipparchus proposed to make a 1 day correction after 4 Calippic cycles. A Hipparchic cycle lasts 111035 days instead of 111036 days (4 Calippic cycles). He decided to make that correction, because he found that the tropical year is about 1/300 of a day shorter than 365 + 1/4 days that Calippus used. This is a very decent approximation for an integer number of lunations to an integer number of days (error only 0.014 days).
Definition and details for lustre (Lustrum):
In ancient Rome, Lustrum, was originally a sacrifice for expiation and purification offered by one of the censors of Rome in the name of the Roman people at the close of the taking of the census, which took place every five years. The Latin word lustrum has survived, and been adopted in some modern languages, in the derived sense of a period of five years.
Swap, do a lustre (Lustrum) to hipparchic cycle conversion.
